Medicine Theseshttps://hdl.handle.net/10023/502024-03-29T00:51:51Z2024-03-29T00:51:51ZCirculatory zinc dyshomeostasis as a novel contributor of thrombosis in obesity and Type II diabetes mellitusHierons, Stephenhttps://hdl.handle.net/10023/294942024-03-15T03:07:01Z2024-06-14T00:00:00ZIndividuals with obesity and Type II diabetes mellitus are particularly susceptible to pathological thrombosis. Notably, the formation of highly compact clots which are resistant to breakdown is likely to contribute to thrombotic risk in these disease groups. High thrombotic risk in these diseases may also be driven by altered Zn²⁺ dynamics in the plasma. Zn²⁺ is a key modulator of haemostasis and influences the activities of numerous coagulation proteins. Normally, Zn²⁺ ions are buffered by human serum albumin (HSA). However, increased levels of non-esterified fatty acids (NEFAs) in obesity and type II diabetes disrupt Zn²⁺ binding to HSA. This may lead to clotting issues, where other Zn²⁺ binding proteins, such as histidine rich glycoprotein (HRG), becomes recipients for these excess Zn²⁺ ions. The interaction between HRG and Zn²⁺ alters the behaviour of proteins involved in clotting, potentially contributing to the abnormal clot structures seen in these patients. This study explores the Zn²⁺-binding properties of HSA in the presence of NEFAs and identifies the second fatty acid binding site (FA2) as the specific site responsible for disrupting Zn²⁺ binding. The investigation also explores the structural and functional aspects of HRG in the presence of Zn²⁺ using various techniques. The findings of this study suggest that Zn²⁺ influences HRG's dynamics and oligomerization. The study has also explored the fibrin clot properties in obese individuals before and after bariatric surgery, correlating changes in fibrin clot properties with clinical parameters. Correlations were found between fibrin clot density and other clinical markers such as % HbA1c, triglycerides, C-reactive protein, and fibrinogen concentrations. Overall, this research underscores how altered Zn²⁺ dynamics in obesity and Type II diabetes can affect blood clotting, offering insights into potential mechanisms leading to abnormal clot structures in obesity and type II diabetes.
2024-06-14T00:00:00ZHierons, StephenIndividuals with obesity and Type II diabetes mellitus are particularly susceptible to pathological thrombosis. Notably, the formation of highly compact clots which are resistant to breakdown is likely to contribute to thrombotic risk in these disease groups. High thrombotic risk in these diseases may also be driven by altered Zn²⁺ dynamics in the plasma. Zn²⁺ is a key modulator of haemostasis and influences the activities of numerous coagulation proteins. Normally, Zn²⁺ ions are buffered by human serum albumin (HSA). However, increased levels of non-esterified fatty acids (NEFAs) in obesity and type II diabetes disrupt Zn²⁺ binding to HSA. This may lead to clotting issues, where other Zn²⁺ binding proteins, such as histidine rich glycoprotein (HRG), becomes recipients for these excess Zn²⁺ ions. The interaction between HRG and Zn²⁺ alters the behaviour of proteins involved in clotting, potentially contributing to the abnormal clot structures seen in these patients. This study explores the Zn²⁺-binding properties of HSA in the presence of NEFAs and identifies the second fatty acid binding site (FA2) as the specific site responsible for disrupting Zn²⁺ binding. The investigation also explores the structural and functional aspects of HRG in the presence of Zn²⁺ using various techniques. The findings of this study suggest that Zn²⁺ influences HRG's dynamics and oligomerization. The study has also explored the fibrin clot properties in obese individuals before and after bariatric surgery, correlating changes in fibrin clot properties with clinical parameters. Correlations were found between fibrin clot density and other clinical markers such as % HbA1c, triglycerides, C-reactive protein, and fibrinogen concentrations. Overall, this research underscores how altered Zn²⁺ dynamics in obesity and Type II diabetes can affect blood clotting, offering insights into potential mechanisms leading to abnormal clot structures in obesity and type II diabetes.Use of data-driven methods to search Electronic Health Records (EHRs) in aid of clinical trial recruitmentShi, Wenhttps://hdl.handle.net/10023/291702024-02-10T03:09:57Z2022-06-17T00:00:00ZRecruiting participants into clinical studies is resource-intensive. However, nearly half of the
trials fail to recruit enough participants, which lead to early termination or poor power of a
study. Digitisation of health care records has ushered in second use of electronic health records
(EHRs). One application is for participant identification and recruitment. Development of
advanced analytics has also added more possibility to that end. In this thesis, an evaluation of
an EHRs-based recruitment support service is presented first. Following that is a study of the
contents of eligibility criteria and its availability in EHRs. A systematic review of advanced
analytics applied to EHRs for recruitment purposes is reported after that. Finally, a
retrospective study of identifying eligible participants for nine clinical studies from EHRs using
case-based reasoning method is presented. It was found that EHRs-based recruitment service
might have difficulty in identifying patients with certain symptoms and minor conditions due
to lack of access to the full set of health care data. Study on eligibility criteria also corroborated
that need to access primary care data and to involve advanced analytics in cohort identification
in order to address different types of eligibility criteria. The review included 11 relevant papers
and found that most were in-silico studies except for one interventional study. Performances
could not be synthesised due to huge differences in experiment set-ups, including trial domain,
number of trials used, analysis unit, outcome definition, evaluation method. A study using
NLP-incorporated case-based reasoning generated good performance indicated by a relatively
comprehensive set of measures. Adaptation of case-based reasoning method to EHRs for
patient recruitment in SHARE showed good differentiation performances in seven projects.
But it did not perform well when evaluated by information retrieval metrics. The results
reflected that structured data alone cannot realise the full potential of the computable method,
echoing the findings from the other studies.
2022-06-17T00:00:00ZShi, WenRecruiting participants into clinical studies is resource-intensive. However, nearly half of the
trials fail to recruit enough participants, which lead to early termination or poor power of a
study. Digitisation of health care records has ushered in second use of electronic health records
(EHRs). One application is for participant identification and recruitment. Development of
advanced analytics has also added more possibility to that end. In this thesis, an evaluation of
an EHRs-based recruitment support service is presented first. Following that is a study of the
contents of eligibility criteria and its availability in EHRs. A systematic review of advanced
analytics applied to EHRs for recruitment purposes is reported after that. Finally, a
retrospective study of identifying eligible participants for nine clinical studies from EHRs using
case-based reasoning method is presented. It was found that EHRs-based recruitment service
might have difficulty in identifying patients with certain symptoms and minor conditions due
to lack of access to the full set of health care data. Study on eligibility criteria also corroborated
that need to access primary care data and to involve advanced analytics in cohort identification
in order to address different types of eligibility criteria. The review included 11 relevant papers
and found that most were in-silico studies except for one interventional study. Performances
could not be synthesised due to huge differences in experiment set-ups, including trial domain,
number of trials used, analysis unit, outcome definition, evaluation method. A study using
NLP-incorporated case-based reasoning generated good performance indicated by a relatively
comprehensive set of measures. Adaptation of case-based reasoning method to EHRs for
patient recruitment in SHARE showed good differentiation performances in seven projects.
But it did not perform well when evaluated by information retrieval metrics. The results
reflected that structured data alone cannot realise the full potential of the computable method,
echoing the findings from the other studies.Genomic investigation of antimicrobial resistant enterococciMcHugh, Martin Patrickhttps://hdl.handle.net/10023/289632024-02-15T03:09:45Z2024-06-14T00:00:00ZEnterococcus faecium and Enterococcus faecalis are important causes of healthcare-associated infections in immunocompromised patients. Enterococci thrive in modern healthcare settings, being able to resist killing by a range of antimicrobial agents, persist in the environment, and adapt to changing circumstances. In Scotland, rates of vancomycin resistant E. faecium (VREfm) have risen almost 150% in recent years leaving few treatment options and challenging healthcare delivery. Resistance to the last line agent linezolid has also been detected in E. faecalis. Whole genome sequencing (WGS) allows investigation of the population structure and transmission of microorganisms, and identification of antimicrobial resistance mechanisms. The aim of this thesis was to use WGS to understand the molecular epidemiology of antimicrobial resistant enterococci from human healthcare settings in Scotland. Analysis of some of the earliest identified Scottish linezolid-resistant E. faecalis showed the resistance mechanism, optrA, was present in unrelated lineages and in different genetic elements, suggesting multiple introductions from a larger reservoir. To inform transmission investigations, within-patient diversity of VREfm was explored showing ~30% of patients carried multiple lineages and identifying a within-patient diversity threshold for transmission studies. WGS was then applied to a large nosocomial outbreak of VREfm, highlighting a complex network of related variants across multiple wards. Having examined within-hospital transmission, the role of regional relationships was investigated which showed that VREfm in Scotland is driven by multiple clones transmitted within individual Health Boards with occasional spread between regions. The most common lineage in the national collection (ST203) was estimated to have been present in Scotland since around 2005, highlighting its persistence in the face of increasing infection prevention and control measures. This thesis provides a starting point for genomic surveillance of enterococci in Scotland, and a basis for interventional studies aiming to reduce the burden of enterococcal infections.
2024-06-14T00:00:00ZMcHugh, Martin PatrickEnterococcus faecium and Enterococcus faecalis are important causes of healthcare-associated infections in immunocompromised patients. Enterococci thrive in modern healthcare settings, being able to resist killing by a range of antimicrobial agents, persist in the environment, and adapt to changing circumstances. In Scotland, rates of vancomycin resistant E. faecium (VREfm) have risen almost 150% in recent years leaving few treatment options and challenging healthcare delivery. Resistance to the last line agent linezolid has also been detected in E. faecalis. Whole genome sequencing (WGS) allows investigation of the population structure and transmission of microorganisms, and identification of antimicrobial resistance mechanisms. The aim of this thesis was to use WGS to understand the molecular epidemiology of antimicrobial resistant enterococci from human healthcare settings in Scotland. Analysis of some of the earliest identified Scottish linezolid-resistant E. faecalis showed the resistance mechanism, optrA, was present in unrelated lineages and in different genetic elements, suggesting multiple introductions from a larger reservoir. To inform transmission investigations, within-patient diversity of VREfm was explored showing ~30% of patients carried multiple lineages and identifying a within-patient diversity threshold for transmission studies. WGS was then applied to a large nosocomial outbreak of VREfm, highlighting a complex network of related variants across multiple wards. Having examined within-hospital transmission, the role of regional relationships was investigated which showed that VREfm in Scotland is driven by multiple clones transmitted within individual Health Boards with occasional spread between regions. The most common lineage in the national collection (ST203) was estimated to have been present in Scotland since around 2005, highlighting its persistence in the face of increasing infection prevention and control measures. This thesis provides a starting point for genomic surveillance of enterococci in Scotland, and a basis for interventional studies aiming to reduce the burden of enterococcal infections.Mechanisms of action of ProTide NUC-1031 and cisplatin combination chemotherapyPatel, Dillumhttps://hdl.handle.net/10023/287582023-11-25T03:05:47Z2023-11-28T00:00:00ZBiliary tract cancers and advanced ovarian cancers are associated with a high mortality rate. Treatment for ovarian cancers have previously consisted of a regimen of intravenous gemcitabine and cisplatin, administered over a number of weeks. This remains the current treatment option for biliary tract cancers. Gemcitabine is associated with drug resistance via a number of resistance mechanisms. NUC-1031, a phosphoramidate modification of gemcitabine, was developed to circumvent these mechanisms. NUC-1031, is the first anti-cancer ProTide to enter the clinic and was investigated in a Phase III trial for biliary tract cancer in combination with cisplatin. Understanding its mode of action may help to improve treatment options and determine a suitable use in patients. It is hypothesised that synergistic effects may occur in combination with cisplatin, where NUC-1031 may sensitise cells to cisplatin lesions via incorporation into DNA.
The kinetics of activation of NUC-1031 and mode of action, both as a single agent and in combination with cisplatin were assessed. NUC-1031 displayed slower activation kinetics than gemcitabine, however remained detectable and continued to exert an effect for a prolonged period after treatment. NUC-1031 was found to generate the active metabolites dFdCDP and dFdCTP in cells. The nucleotide analogue dFDCTP is incorporated into DNA which prevents elongation of growing strands in S phase, leading to replication fork collapse and formation of cytotoxic double strand breaks. Combinations of NUC-1031 and cisplatin were also investigated by measuring the DNA damage response and cell cycle distribution over time. NUC-1031 may inhibit cisplatin repair through its incorporation during DNA repair. The slow activation and the prolonged effects of NUC-1031 may be a favourable trait when included in drug combinations, as the active metabolite of NUC-1031 may be available to interact with additional agents in the drug treatment.
2023-11-28T00:00:00ZPatel, DillumBiliary tract cancers and advanced ovarian cancers are associated with a high mortality rate. Treatment for ovarian cancers have previously consisted of a regimen of intravenous gemcitabine and cisplatin, administered over a number of weeks. This remains the current treatment option for biliary tract cancers. Gemcitabine is associated with drug resistance via a number of resistance mechanisms. NUC-1031, a phosphoramidate modification of gemcitabine, was developed to circumvent these mechanisms. NUC-1031, is the first anti-cancer ProTide to enter the clinic and was investigated in a Phase III trial for biliary tract cancer in combination with cisplatin. Understanding its mode of action may help to improve treatment options and determine a suitable use in patients. It is hypothesised that synergistic effects may occur in combination with cisplatin, where NUC-1031 may sensitise cells to cisplatin lesions via incorporation into DNA.
The kinetics of activation of NUC-1031 and mode of action, both as a single agent and in combination with cisplatin were assessed. NUC-1031 displayed slower activation kinetics than gemcitabine, however remained detectable and continued to exert an effect for a prolonged period after treatment. NUC-1031 was found to generate the active metabolites dFdCDP and dFdCTP in cells. The nucleotide analogue dFDCTP is incorporated into DNA which prevents elongation of growing strands in S phase, leading to replication fork collapse and formation of cytotoxic double strand breaks. Combinations of NUC-1031 and cisplatin were also investigated by measuring the DNA damage response and cell cycle distribution over time. NUC-1031 may inhibit cisplatin repair through its incorporation during DNA repair. The slow activation and the prolonged effects of NUC-1031 may be a favourable trait when included in drug combinations, as the active metabolite of NUC-1031 may be available to interact with additional agents in the drug treatment.Title redactedPinker, India Hollyhttps://hdl.handle.net/10023/285612023-10-26T10:20:00Z2023-11-28T00:00:00ZAbstract redacted
2023-11-28T00:00:00ZPinker, India HollyAbstract redactedAn investigation into the clinical and genomic diversity of Human Papillomavirus in invasive disease in Scotland and the implications of new technologiesGuerendiain Regalado, Danielhttps://hdl.handle.net/10023/285542023-11-20T16:34:41Z2023-11-28T00:00:00ZThis study investigated the prevalence of human papillomavirus (HPV) in different HPV-driven cancers in Scotland, including cervical, oropharyngeal, and anal. The study found that 91.5% of cervical, 55% of oropharyngeal and 88.6% of anal cancers are driven by HPV. Data has shown that most of these infections could potentially be prevented by the HPV vaccines.
This research also investigated novel molecular methods for detecting HPV, such as droplet digital PCR (ddPCR) and next-generation sequencing (NGS), which can provide more comprehensive data about the virus and its various (sub)-lineages. ddPCR was used to determine the number of HPV 16 copies per cell in anal cancers. It was found that the qualitative presence of HPV and high viral load was associated with more prolonged survival in anal cancers, consistent with other HPV-driven cancers.
Prior to the sequencing, three different extraction methods were examined to identify which one could be best for NGS downstream. Additionally, a bioinformatics pipeline was set up and validated by comparing results with the International HPV Reference Centre.
NGS was used to analyse the genome of the HPV 16 detected in anal cancer samples and anal swabs from an asymptomatic male population. By analysing the whole genome of the virus, HPV 16 sub-lineages were identified. Lineages A1 and A2 were the most prevalent in both groups, and only minimal differences were detected for sub-linages B1, C1, and D1. Analysing sub-lineages and clinical data showed no overall survival differences between A1 and non-A1 sub-lineages.
In addition, the potential of NGS for HPV diagnosis, compared with conventional HPV testing and how NGS may be applied for the detection and risk stratification for HPV infection and associated diseases was also described. Finally, a case scenario was presented for guidance in implementing direct sequencing in an HPV reference laboratory.
2023-11-28T00:00:00ZGuerendiain Regalado, DanielThis study investigated the prevalence of human papillomavirus (HPV) in different HPV-driven cancers in Scotland, including cervical, oropharyngeal, and anal. The study found that 91.5% of cervical, 55% of oropharyngeal and 88.6% of anal cancers are driven by HPV. Data has shown that most of these infections could potentially be prevented by the HPV vaccines.
This research also investigated novel molecular methods for detecting HPV, such as droplet digital PCR (ddPCR) and next-generation sequencing (NGS), which can provide more comprehensive data about the virus and its various (sub)-lineages. ddPCR was used to determine the number of HPV 16 copies per cell in anal cancers. It was found that the qualitative presence of HPV and high viral load was associated with more prolonged survival in anal cancers, consistent with other HPV-driven cancers.
Prior to the sequencing, three different extraction methods were examined to identify which one could be best for NGS downstream. Additionally, a bioinformatics pipeline was set up and validated by comparing results with the International HPV Reference Centre.
NGS was used to analyse the genome of the HPV 16 detected in anal cancer samples and anal swabs from an asymptomatic male population. By analysing the whole genome of the virus, HPV 16 sub-lineages were identified. Lineages A1 and A2 were the most prevalent in both groups, and only minimal differences were detected for sub-linages B1, C1, and D1. Analysing sub-lineages and clinical data showed no overall survival differences between A1 and non-A1 sub-lineages.
In addition, the potential of NGS for HPV diagnosis, compared with conventional HPV testing and how NGS may be applied for the detection and risk stratification for HPV infection and associated diseases was also described. Finally, a case scenario was presented for guidance in implementing direct sequencing in an HPV reference laboratory.Investigating the localisation and function of TRPM2 in endomembranesAlthobaiti, Mohammedhttps://hdl.handle.net/10023/282332023-09-04T09:02:10Z2023-11-28T00:00:00ZAbstract redacted
2023-11-28T00:00:00ZAlthobaiti, MohammedAbstract redactedTitle redactedAbbondanza, Filippohttps://hdl.handle.net/10023/281282023-08-14T09:30:25Z2023-11-28T00:00:00ZAbstract redacted
2023-11-28T00:00:00ZAbbondanza, FilippoAbstract redactedEvaluation of the tuberculosis-molecular bacterial load assay for tuberculosis diagnosis and monitoring response to standard anti-tuberculosis therapyMusisi, Emmanuelhttps://hdl.handle.net/10023/280352023-08-18T10:32:28Z2023-06-16T00:00:00ZTuberculosis (TB) is a difficult disease to treat, requiring a minimum of six months on a combination of four antibiotics. This thesis reports the first systematic evaluation of the St Andrews' developed RNA-based tuberculosis-Molecular Bacterial Load Assay (TB-MBLA) for its accuracy to diagnose tuberculosis and measure treatment response in comparison to current standard-of-care tests. Presumptive TB patients were enrolled in Uganda and assessed for TB using TB-MBLA versus Xpert MTB/RIF Ultra (Xpert-Ultra) and stained smear fluorescent microscopy (SSM-FM) using sputum MGIT culture as the gold standard and reference test. Out of the 210 presumptive cases, 129 (61.4%) participants tested TB positive on the Xpert-Ultra in the sputum cohort and they were enrolled into the treatment arm and consequently monitored for six months. At baseline, 6/210 (2.9%) sputum MGIT culture results were indeterminate due to contamination, and they were excluded from the calculation of the sensitivity, specificity, and predictive values.
Sensitivity for TB-MBLA and Xpert-Ultra (95%CI) was 99%(95-100) which was higher compared to 76%(65-83) for SSM-FM. TB-MBLA specificity at 90%(83-96) was higher than the 76%(68-86) for Xpert-Ultra but less than 98%(93-100) for SSM-FM. In the treatment follow-up arm, TB positivity rates reduced for all tests. TB-MBLA positivity reduction was consistent with that of the MGIT culture but different from that of Xpert-Ultra which occurred remarkably slower. Consequently, 31 participants were still Xpert-Ultra positive at the end treatment course. Three-month post treatment follow-up of the 31 Xpert-Ultra positive cases revealed no TB both clinically and on TB-MBLA and MGIT tests. In the stool cohort, TB-MBLA detected TB in 57/100 participants including 49 who were confirmed positive for pTB on sputum MGIT culture. Fifty-seven percent (57%) of the indeterminate stool culture were positive on TB-MBLA. The findings prove that TB-MBLA's potential utility as both a diagnostic and treatment monitoring tool of TB in research and routine healthcare.
2023-06-16T00:00:00ZMusisi, EmmanuelTuberculosis (TB) is a difficult disease to treat, requiring a minimum of six months on a combination of four antibiotics. This thesis reports the first systematic evaluation of the St Andrews' developed RNA-based tuberculosis-Molecular Bacterial Load Assay (TB-MBLA) for its accuracy to diagnose tuberculosis and measure treatment response in comparison to current standard-of-care tests. Presumptive TB patients were enrolled in Uganda and assessed for TB using TB-MBLA versus Xpert MTB/RIF Ultra (Xpert-Ultra) and stained smear fluorescent microscopy (SSM-FM) using sputum MGIT culture as the gold standard and reference test. Out of the 210 presumptive cases, 129 (61.4%) participants tested TB positive on the Xpert-Ultra in the sputum cohort and they were enrolled into the treatment arm and consequently monitored for six months. At baseline, 6/210 (2.9%) sputum MGIT culture results were indeterminate due to contamination, and they were excluded from the calculation of the sensitivity, specificity, and predictive values.
Sensitivity for TB-MBLA and Xpert-Ultra (95%CI) was 99%(95-100) which was higher compared to 76%(65-83) for SSM-FM. TB-MBLA specificity at 90%(83-96) was higher than the 76%(68-86) for Xpert-Ultra but less than 98%(93-100) for SSM-FM. In the treatment follow-up arm, TB positivity rates reduced for all tests. TB-MBLA positivity reduction was consistent with that of the MGIT culture but different from that of Xpert-Ultra which occurred remarkably slower. Consequently, 31 participants were still Xpert-Ultra positive at the end treatment course. Three-month post treatment follow-up of the 31 Xpert-Ultra positive cases revealed no TB both clinically and on TB-MBLA and MGIT tests. In the stool cohort, TB-MBLA detected TB in 57/100 participants including 49 who were confirmed positive for pTB on sputum MGIT culture. Fifty-seven percent (57%) of the indeterminate stool culture were positive on TB-MBLA. The findings prove that TB-MBLA's potential utility as both a diagnostic and treatment monitoring tool of TB in research and routine healthcare.Trace metal-protein interactions in plasma of relevance to health and immune functioningWu, Dongmeihttps://hdl.handle.net/10023/279242023-07-11T02:02:56Z2023-11-28T00:00:00ZTrace metal ions play many critical roles in biological functions in humans. Plasma proteins such as human serum albumin (HSA) are primarily responsible for the circulatory transport of metal ions and as such are relevant to health and immune functioning. To further understand the biological processes and some diseases associated with defective homeostasis of metal ions (including Co²⁺, Zn²⁺, Cd²⁺ and Cu²⁺), a deeper understanding of the properties of protein-metal ion interactions is required. On HSA, three metal-binding sites involving in binding to these metal ions are known, including sites A (His67 site), B (His9 site) and the N-terminal site (His3 site), which play different roles in binding different metal ions. Additionally, metal ion states are of clinical importance in immune system. Among these metal ions, defective homeostasis of Cu²⁺ has been proposed to be related to the development of celiac disease (CD), by regulating tissue transglutaminase (TG2) activity in extracellular environment. Thus, the aims of this project are to elucidate properties of metal ion-HSA interactions and investigate potential role for Cu²⁺ in TG2 activity regulation.
Employing site-directed mutagenesis, isothermal titration calorimetry (ITC) and circular dichroism (CD), the results presented here indicate that Co²⁺ preferentially binds to HSA at site B, followed by site A and subsequentially binds to multiple weak-affinity sites. Additionally, the presence of 5 molar equivalents of palmitate can trigger structural changes and diminish Co²⁺ binding to sites A and B of HSA. An investigation of Zn²⁺ binding using mutagenesis and ITC revealed that this ion preferentially binds to site A, followed by site B, which is in firm agreement with previous data. In addition, Zn²⁺ binding to site A was dramatically reduced by addition of 5 molar equivalents of palmitate. ITC results in combination with ¹¹¹Cd-NMR spectroscopy suggest sites B and A are the two major binding sites participating in Cd²⁺ binding to HSA. Additionally, the results confirm that His9 is the indispensable histidine residue contributing to site B. Intriguingly, inspection of these data reveals that binding modes of different metal ions in different metal-binding sites (especially in site A) vary substantially. Both His67 and His247 participate in the “intact” site A in Zn²⁺ binding; however, His247 may play a less important role than His67 in Co²⁺ and Cd²⁺ binding to site A. Regarding to Cu²⁺ binding to HSA, it primarily binds to the N-terminal site and secondly binds to site A, supported by the results from ITC and EPR spectroscopy. Compellingly, the data presented here also demonstrate that Cu²⁺ is a potent inhibitor of TG2, providing an insight into deeper understanding of the development of CD. Collectively, these data provide a more comprehensive understanding of the properties of Co²⁺, Zn²⁺, Cd²⁺ and Cu²⁺ interactions with HSA and their interplay with fatty acids, contributing to more accurate insights into metal ion distribution and speciation mediated by HSA and their implications in health.
2023-11-28T00:00:00ZWu, DongmeiTrace metal ions play many critical roles in biological functions in humans. Plasma proteins such as human serum albumin (HSA) are primarily responsible for the circulatory transport of metal ions and as such are relevant to health and immune functioning. To further understand the biological processes and some diseases associated with defective homeostasis of metal ions (including Co²⁺, Zn²⁺, Cd²⁺ and Cu²⁺), a deeper understanding of the properties of protein-metal ion interactions is required. On HSA, three metal-binding sites involving in binding to these metal ions are known, including sites A (His67 site), B (His9 site) and the N-terminal site (His3 site), which play different roles in binding different metal ions. Additionally, metal ion states are of clinical importance in immune system. Among these metal ions, defective homeostasis of Cu²⁺ has been proposed to be related to the development of celiac disease (CD), by regulating tissue transglutaminase (TG2) activity in extracellular environment. Thus, the aims of this project are to elucidate properties of metal ion-HSA interactions and investigate potential role for Cu²⁺ in TG2 activity regulation.
Employing site-directed mutagenesis, isothermal titration calorimetry (ITC) and circular dichroism (CD), the results presented here indicate that Co²⁺ preferentially binds to HSA at site B, followed by site A and subsequentially binds to multiple weak-affinity sites. Additionally, the presence of 5 molar equivalents of palmitate can trigger structural changes and diminish Co²⁺ binding to sites A and B of HSA. An investigation of Zn²⁺ binding using mutagenesis and ITC revealed that this ion preferentially binds to site A, followed by site B, which is in firm agreement with previous data. In addition, Zn²⁺ binding to site A was dramatically reduced by addition of 5 molar equivalents of palmitate. ITC results in combination with ¹¹¹Cd-NMR spectroscopy suggest sites B and A are the two major binding sites participating in Cd²⁺ binding to HSA. Additionally, the results confirm that His9 is the indispensable histidine residue contributing to site B. Intriguingly, inspection of these data reveals that binding modes of different metal ions in different metal-binding sites (especially in site A) vary substantially. Both His67 and His247 participate in the “intact” site A in Zn²⁺ binding; however, His247 may play a less important role than His67 in Co²⁺ and Cd²⁺ binding to site A. Regarding to Cu²⁺ binding to HSA, it primarily binds to the N-terminal site and secondly binds to site A, supported by the results from ITC and EPR spectroscopy. Compellingly, the data presented here also demonstrate that Cu²⁺ is a potent inhibitor of TG2, providing an insight into deeper understanding of the development of CD. Collectively, these data provide a more comprehensive understanding of the properties of Co²⁺, Zn²⁺, Cd²⁺ and Cu²⁺ interactions with HSA and their interplay with fatty acids, contributing to more accurate insights into metal ion distribution and speciation mediated by HSA and their implications in health.The nature of the intra-ocular fluids and the pressure equilibrium in the eyeDuke-Elder, William Stewarthttps://hdl.handle.net/10023/277632023-06-29T02:00:41Z1927-03-01T00:00:00ZThe present Thesis is, in the first place, a study in the bio-chemistry of the intra-ocular fluids under normal conditions and as they appear under experimental variations from the normal. It is by no means a new study, and much work - often, it is true, fragmentary - has been done upon it by different authors at various times for varying purposes. This work I have freely drawn upon; where there have been gaps in our knowledge I have endeavoured to fill them, and to present the whole in a coherent form. By unifying the whole, a fairly authoritative statement of the physico-chemical nature of the intra-ocular fluids can be deducted. Thereafter, in the light of these findings, a study is made of the factors responsible for the maintenance and variation of the intra-ocular pressure.
1927-03-01T00:00:00ZDuke-Elder, William StewartThe present Thesis is, in the first place, a study in the bio-chemistry of the intra-ocular fluids under normal conditions and as they appear under experimental variations from the normal. It is by no means a new study, and much work - often, it is true, fragmentary - has been done upon it by different authors at various times for varying purposes. This work I have freely drawn upon; where there have been gaps in our knowledge I have endeavoured to fill them, and to present the whole in a coherent form. By unifying the whole, a fairly authoritative statement of the physico-chemical nature of the intra-ocular fluids can be deducted. Thereafter, in the light of these findings, a study is made of the factors responsible for the maintenance and variation of the intra-ocular pressure.Using self-determination theory and the social identity approach to understand physical activity during the COVID-19 pandemicSchertzinger, Meredith Mariehttps://hdl.handle.net/10023/277352023-11-06T13:58:55Z2023-06-16T00:00:00ZThe aim of the PhD was to utilise Self-Determination Theory (SDT) and the Social Identity Approach (SIA) to understand individuals’ physical activity behaviours during the COVID-19 pandemic. Based on the theoretical tenets of SDT and SIA, an individual who is part of a physical activity environment in which they perceive a shared group identity and feel supported in their psychological needs, in time, will internalise and value routine physical activity. Governmental restrictions in response to the COVID-19 pandemic prevented group physical activity, disrupting pre-pandemic physical activity habits. Study 1, a cross-sectional survey, analysed the behavioural change in running habits during COVID-19 restrictions and found that SDT and SIA variables supported runners’ physical activity and mental well-being. Before the pandemic, there was limited research on the association of SDT and SIA variables in an online exercise setting. Study 2, a cross-sectional survey of online exercise participants, found that the exercise class leader could be just as effective online as in person. In addition, leaders’ ability to create a group identity indirectly improved participants’ class effort, enjoyment, and attendance. Finally, studies 3 and 4 experimentally manipulated a leader’s use of identity entrepreneurship (crafting of ‘we-ness’) to examine the causal impact this had on participants’ online exercise class experiences. The experimental manipulation was successful, and identity entrepreneurship significantly indirectly affected participants’ class experiences. This research expands SIA leadership research by showing that online exercise leaders’ ability to establish and maintain a group identity improves their participants’ class experiences. Beyond the pandemic, this research demonstrated that SDT and SIA variables could be used to understand how individuals will respond and adapt to sudden changes in physical group memberships and normative physical activity routines.
2023-06-16T00:00:00ZSchertzinger, Meredith MarieThe aim of the PhD was to utilise Self-Determination Theory (SDT) and the Social Identity Approach (SIA) to understand individuals’ physical activity behaviours during the COVID-19 pandemic. Based on the theoretical tenets of SDT and SIA, an individual who is part of a physical activity environment in which they perceive a shared group identity and feel supported in their psychological needs, in time, will internalise and value routine physical activity. Governmental restrictions in response to the COVID-19 pandemic prevented group physical activity, disrupting pre-pandemic physical activity habits. Study 1, a cross-sectional survey, analysed the behavioural change in running habits during COVID-19 restrictions and found that SDT and SIA variables supported runners’ physical activity and mental well-being. Before the pandemic, there was limited research on the association of SDT and SIA variables in an online exercise setting. Study 2, a cross-sectional survey of online exercise participants, found that the exercise class leader could be just as effective online as in person. In addition, leaders’ ability to create a group identity indirectly improved participants’ class effort, enjoyment, and attendance. Finally, studies 3 and 4 experimentally manipulated a leader’s use of identity entrepreneurship (crafting of ‘we-ness’) to examine the causal impact this had on participants’ online exercise class experiences. The experimental manipulation was successful, and identity entrepreneurship significantly indirectly affected participants’ class experiences. This research expands SIA leadership research by showing that online exercise leaders’ ability to establish and maintain a group identity improves their participants’ class experiences. Beyond the pandemic, this research demonstrated that SDT and SIA variables could be used to understand how individuals will respond and adapt to sudden changes in physical group memberships and normative physical activity routines.Mechanisms of action of 3’-deoxyadenosine in treating clear cell renal cell carcinomaKudsy, Maryhttps://hdl.handle.net/10023/276602023-05-23T02:06:06Z2023-06-12T00:00:00ZAlthough treatment strategies for advanced and metastatic clear cell renal cell carcinoma (ccRCC) have markedly evolved with the recent use of immune-checkpoint inhibitor (ICI)-based combinations, most patients eventually develop resistance to these therapies. Therefore, there is still an urgent need for the development of effective treatment options. NUC-7738, a novel ProTide transformation of the nucleoside analogue 3ﹶ-deoxyadenosine, releases 3ﹶ-deoxyadenosine monophosphate (3’-dAMP) in cells which is then phosphorylated to the di- (3’-dADP) and tri-phosphate forms (3’-dATP). 3’-dAMP might have the ability to activate AMP-activated protein kinase (AMPK), a key cellular energy sensor, and thus disrupt metabolic homeostasis in cancer cells. Furthermore, 3’-dATP might interfere with RNA synthesis affecting protein expression and survival of cancer cells.
The ability of NUC-7738 to activate AMPK through phosphorylation of Th172 was tested in ccRCC cell lines and ex vivo tissue slices of ccRCC from patients. The effect of NUC-7738 on mRNA synthesis and polyadenylation was investigated in two ccRCC cell lines, 786-O and 769-P. AMPK activation by NUC-7738 showed inter-replicate variability and inter-patient variability in ccRCC cell lines and ex vivo tissue slices, respectively, indicating the complexity of the regulation of AMPK phosphorylation. Moreover, mass spectrometry analysis showed that 3’-dATP is the main active metabolite of NUC-7738. Transcriptome data analysis showed mitochondrial gene transcripts of electron transport chain (ETC) complexes were the most significantly altered in both 786-O and 769-P cell lines, with lower expression levels in response to NUC-7738 treatment. This was accompanied by downregulation of the protein expression of ETC complexes subunits. NUC-7738 induced the intrinsic pathway of apoptosis in these cells through the release of cytochrome c from mitochondria and the subsequent activation of caspases -9 and -7. These data suggest that NUC-7738 might inhibit tumour cells growth and proliferation through the inhibition of mitochondrial respiration and the subsequent induction of apoptosis.
2023-06-12T00:00:00ZKudsy, MaryAlthough treatment strategies for advanced and metastatic clear cell renal cell carcinoma (ccRCC) have markedly evolved with the recent use of immune-checkpoint inhibitor (ICI)-based combinations, most patients eventually develop resistance to these therapies. Therefore, there is still an urgent need for the development of effective treatment options. NUC-7738, a novel ProTide transformation of the nucleoside analogue 3ﹶ-deoxyadenosine, releases 3ﹶ-deoxyadenosine monophosphate (3’-dAMP) in cells which is then phosphorylated to the di- (3’-dADP) and tri-phosphate forms (3’-dATP). 3’-dAMP might have the ability to activate AMP-activated protein kinase (AMPK), a key cellular energy sensor, and thus disrupt metabolic homeostasis in cancer cells. Furthermore, 3’-dATP might interfere with RNA synthesis affecting protein expression and survival of cancer cells.
The ability of NUC-7738 to activate AMPK through phosphorylation of Th172 was tested in ccRCC cell lines and ex vivo tissue slices of ccRCC from patients. The effect of NUC-7738 on mRNA synthesis and polyadenylation was investigated in two ccRCC cell lines, 786-O and 769-P. AMPK activation by NUC-7738 showed inter-replicate variability and inter-patient variability in ccRCC cell lines and ex vivo tissue slices, respectively, indicating the complexity of the regulation of AMPK phosphorylation. Moreover, mass spectrometry analysis showed that 3’-dATP is the main active metabolite of NUC-7738. Transcriptome data analysis showed mitochondrial gene transcripts of electron transport chain (ETC) complexes were the most significantly altered in both 786-O and 769-P cell lines, with lower expression levels in response to NUC-7738 treatment. This was accompanied by downregulation of the protein expression of ETC complexes subunits. NUC-7738 induced the intrinsic pathway of apoptosis in these cells through the release of cytochrome c from mitochondria and the subsequent activation of caspases -9 and -7. These data suggest that NUC-7738 might inhibit tumour cells growth and proliferation through the inhibition of mitochondrial respiration and the subsequent induction of apoptosis.“I think it’s a lot harder” – fundamentals for developing a core curriculum in telecommunication and teleconsultation in undergraduate medical education in the UKWetzlmair, Lisa-Christinhttps://hdl.handle.net/10023/275872023-07-06T17:00:54Z2023-06-16T00:00:00ZTelehealth has become increasingly important in modern healthcare systems, as remote communication with colleagues (i.e. telecommunication) and remote consultations with patients (i.e. teleconsultations) increased in the last decades. The workforce should be prepared for working in digitised healthcare systems which demand different skills, competencies, and attitudes. A systematic literature review has shown limited evidence-informed training regarding telecommunication and teleconsultation (TC) at undergraduate level. These results led to the aim of this PhD study: exploring factors that can inform a core curriculum on TC in UK undergraduate medical education.
An additional coverage mixed-methods design was conducted, utilising an online questionnaire and semi-structured interviews. Medical educators and undergraduate medical students in the UK were invited to participate in this study. The development of the questionnaire was based on the Technology Acceptance Model and the results of a test-retest cycle. Quantitative data was analysed descriptively, and qualitative data was analysed inductively and deductively using thematic analysis.
Results indicated that most students and educators have had experiences with TC during the pandemic. Medical schools adapted their curriculum quickly, yet most study participants could not report on the formalities and content of teaching taking place in academic learning environments. The opinions on TC were mixed but students as well as educators think that it requires efficacious triaging systems and different communication skills.
Globally, healthcare systems are increasing the use of telehealth. It is essential to prepare the future workforce for those changes. This study contributed to building the foundation for the development of a TC core curriculum in UK undergraduate medical education.
2023-06-16T00:00:00ZWetzlmair, Lisa-ChristinTelehealth has become increasingly important in modern healthcare systems, as remote communication with colleagues (i.e. telecommunication) and remote consultations with patients (i.e. teleconsultations) increased in the last decades. The workforce should be prepared for working in digitised healthcare systems which demand different skills, competencies, and attitudes. A systematic literature review has shown limited evidence-informed training regarding telecommunication and teleconsultation (TC) at undergraduate level. These results led to the aim of this PhD study: exploring factors that can inform a core curriculum on TC in UK undergraduate medical education.
An additional coverage mixed-methods design was conducted, utilising an online questionnaire and semi-structured interviews. Medical educators and undergraduate medical students in the UK were invited to participate in this study. The development of the questionnaire was based on the Technology Acceptance Model and the results of a test-retest cycle. Quantitative data was analysed descriptively, and qualitative data was analysed inductively and deductively using thematic analysis.
Results indicated that most students and educators have had experiences with TC during the pandemic. Medical schools adapted their curriculum quickly, yet most study participants could not report on the formalities and content of teaching taking place in academic learning environments. The opinions on TC were mixed but students as well as educators think that it requires efficacious triaging systems and different communication skills.
Globally, healthcare systems are increasing the use of telehealth. It is essential to prepare the future workforce for those changes. This study contributed to building the foundation for the development of a TC core curriculum in UK undergraduate medical education.Biological and clinical implications of the non-small cell lung cancer immune contexture : an investigation of the tumour microenvironmentKaghazchi, Bobackhttps://hdl.handle.net/10023/275852023-05-12T02:02:49Z2023-06-16T00:00:00ZAbstract redacted
2023-06-16T00:00:00ZKaghazchi, BobackAbstract redactedTeenage pregnancy among care experienced young people in Fife : a data linkage studyHay, Laura Annhttps://hdl.handle.net/10023/273692023-11-21T03:01:18Z2022-11-29T00:00:00ZBackground: Care experienced young people (CEYP) are thought to be at increased risk of experiencing teenage pregnancy but little is known about teenage pregnancy rates among CEYP in Scotland. Objectives: The study used data linkage techniques to compare teenage pregnancy outcomes for CEYP in Fife with those of their non-care experienced but similarly deprived peers. Methods: Social care administrative data for 1119 females looked after by Fife Council between October 1991 and March 2015 were linked to NHS teenage pregnancy data. Probabilistic linkage was used to match CEYP demographic data (names, sex, date of birth and postcodes) to the Community Health Index (CHI) number. The CHI number was used to identify teenage pregnancy outcomes from national Scottish Morbidity Record (SMR) datasets, SMR01 and SMR02. Outcomes for CEYP were compared with a group of non-care experienced peers from a similar socioeconomic background. Three non-care experienced young people (non-CEYP) were selected for every CEYP, matched by year of birth, sex and socioeconomic status at birth. Results: An acceptable match to a CHI number was achieved for 90.5% (1013/1119) of CEYP. 889 CEYP were fully matched to 2664 non-CEYP. CEYP were more than twice as likely as non-CEYP to experience a live birth before age 20 (RR 2.32, 95% CI 2.06 to 2.62). 38.4% (341/889) of CEYP had a live birth before age 20, compared with 16.5% (440/2664) of non-CEYP (p<0.001).
CEYP were 33% more likely than non-CEYP to experience a termination of pregnancy before age 20 (RR 1.33, 95% CI 1.06 to 1.66). 11.2% (100/889) of CEYP experienced a termination of pregnancy before age 20, compared with 8.5% (226/2664) of non-CEYP (p<0.05).
Conclusions: CEYP were significantly more likely to experience teenage abortion and teenage childbirth than their non-care experienced but similarly deprived peers. High levels of teenage childbirth were observed among CEYP.
2022-11-29T00:00:00ZHay, Laura AnnBackground: Care experienced young people (CEYP) are thought to be at increased risk of experiencing teenage pregnancy but little is known about teenage pregnancy rates among CEYP in Scotland. Objectives: The study used data linkage techniques to compare teenage pregnancy outcomes for CEYP in Fife with those of their non-care experienced but similarly deprived peers. Methods: Social care administrative data for 1119 females looked after by Fife Council between October 1991 and March 2015 were linked to NHS teenage pregnancy data. Probabilistic linkage was used to match CEYP demographic data (names, sex, date of birth and postcodes) to the Community Health Index (CHI) number. The CHI number was used to identify teenage pregnancy outcomes from national Scottish Morbidity Record (SMR) datasets, SMR01 and SMR02. Outcomes for CEYP were compared with a group of non-care experienced peers from a similar socioeconomic background. Three non-care experienced young people (non-CEYP) were selected for every CEYP, matched by year of birth, sex and socioeconomic status at birth. Results: An acceptable match to a CHI number was achieved for 90.5% (1013/1119) of CEYP. 889 CEYP were fully matched to 2664 non-CEYP. CEYP were more than twice as likely as non-CEYP to experience a live birth before age 20 (RR 2.32, 95% CI 2.06 to 2.62). 38.4% (341/889) of CEYP had a live birth before age 20, compared with 16.5% (440/2664) of non-CEYP (p<0.001).
CEYP were 33% more likely than non-CEYP to experience a termination of pregnancy before age 20 (RR 1.33, 95% CI 1.06 to 1.66). 11.2% (100/889) of CEYP experienced a termination of pregnancy before age 20, compared with 8.5% (226/2664) of non-CEYP (p<0.05).
Conclusions: CEYP were significantly more likely to experience teenage abortion and teenage childbirth than their non-care experienced but similarly deprived peers. High levels of teenage childbirth were observed among CEYP.The HLA class I peptidome of extracellular vesicles : detection of antigenic epitopes relevant to immunotherapyBoyne, Caitlinhttps://hdl.handle.net/10023/273072024-03-12T10:51:52Z2023-06-16T00:00:00ZExtracellular vesicles (EVs) have been indicated as key players in the communication between cancer cells and the host microenvironment. EVs are known to express human leukocyte antigen class I (HLA-I) molecules and the landscape of the immunopeptidome may be a defining feature of EVs that allows them to have a significant impact on anti-tumour immune responses. Whilst the peptide ligandome presented by cell surface HLA-I molecules on cancer cells has been extensively investigated, the peptide ligandome on EVs is yet to be defined. To address this, we characterised the HLA-I immunopeptidome of EVs derived from multiple myeloma and melanoma cancer cells. It was established that the HLA-I immunopeptidome on EVs can feature T cell epitopes with known immunogenicity and peptides derived from known tumour associated antigens (TAAs), as well as neoantigens. Further, due to the similarity in peptides identified between the HLA-I immunopeptidome on the cancer cell surface with that on the EVs surface, it was determined that EVs can provide insights into the effects that cancer cells may be having on the immune system. This insight could be of great clinical benefit as it suggests HLA-I on EVs can be considered a rich source of information regarding cancer, that can be obtained without an invasive biopsy. To further explore this possibility, EVs were isolated from plasma of patients diagnosed with multiple myeloma, melanoma or breast cancer and the HLA-I immunopeptidomes were characterised. Both T cell epitopes with known immunogenicity and peptides derived from known TAAs were identifiable in the patient samples. The information obtained from an easily acquired blood sample can inform on the cancer itself, may aid in the detection of important diagnostic or prognostic biomarkers, enable easier tracking of treatment responses, be utilised in novel immunotherapies and be employed as carriers for use as novel cancer vaccines.
2023-06-16T00:00:00ZBoyne, CaitlinExtracellular vesicles (EVs) have been indicated as key players in the communication between cancer cells and the host microenvironment. EVs are known to express human leukocyte antigen class I (HLA-I) molecules and the landscape of the immunopeptidome may be a defining feature of EVs that allows them to have a significant impact on anti-tumour immune responses. Whilst the peptide ligandome presented by cell surface HLA-I molecules on cancer cells has been extensively investigated, the peptide ligandome on EVs is yet to be defined. To address this, we characterised the HLA-I immunopeptidome of EVs derived from multiple myeloma and melanoma cancer cells. It was established that the HLA-I immunopeptidome on EVs can feature T cell epitopes with known immunogenicity and peptides derived from known tumour associated antigens (TAAs), as well as neoantigens. Further, due to the similarity in peptides identified between the HLA-I immunopeptidome on the cancer cell surface with that on the EVs surface, it was determined that EVs can provide insights into the effects that cancer cells may be having on the immune system. This insight could be of great clinical benefit as it suggests HLA-I on EVs can be considered a rich source of information regarding cancer, that can be obtained without an invasive biopsy. To further explore this possibility, EVs were isolated from plasma of patients diagnosed with multiple myeloma, melanoma or breast cancer and the HLA-I immunopeptidomes were characterised. Both T cell epitopes with known immunogenicity and peptides derived from known TAAs were identifiable in the patient samples. The information obtained from an easily acquired blood sample can inform on the cancer itself, may aid in the detection of important diagnostic or prognostic biomarkers, enable easier tracking of treatment responses, be utilised in novel immunotherapies and be employed as carriers for use as novel cancer vaccines.De novo genome assembly of Plasmodium knowlesi from contemporary clinical isolates - a novel scalable resource to take forward malaria researchOresegun, Damilola Rasheedhttps://hdl.handle.net/10023/272742023-04-24T21:10:51Z2022-06-17T00:00:00ZPlasmodium knowlesi is a zoonotic malaria parasite of Southeastern macaque monkeys that causes zoonotic malaria in humans. P. knowlesi is also an experimental model for malaria, and information on P. knowlesi largely stem from experimental lines first isolated >four decades ago, rather than contemporary isolates causing human infections. The experimental lines are laboratory-restricted and have become relatively genetically stagnant and free from the selection pressure that would naturally occur in nature. Within the P. knowlesi genome exist the Schizont Infected Cell Agglutination variant antigen (SICAvar) and Plasmodium knowlesi interspersed repeat (kir) multigene families significant, which are of biological and scientific interest. To provide context using contemporary clinical isolates, this project aimed to generate high-quality genome sequences using long-sequencing from clinical ‘wild-type’ samples from infected patients. This includes generating new information on variant multigene families in P. knowlesi genomes generated from clinical patient whole blood. The work presented here details a method to deplete leucocytes in thawed P. knowlesi-infected patient whole blood samples to generate parasite-enriched DNA for whole-genome sequencing, resulting in >95% human DNA reduction. The extracted DNA was sequenced with long-read sequencing technology to create de novo whole-genome assemblies. From these, two isolate genomes representing the two dimorphic clusters of P. knowlesi in clinical samples were analysed. The generated genomes are highly syntenic to the published reference genome, sharing >4500 orthologous clusters with the PKNH reference genome. However, the number of SICAvar and kir genes present in the dataset deviated from the published reference genomes of P. knowlesi. The successful generation and construction of these patient genomes aid further interrogation of the contemporary P. knowlesi genome, with a focus on the constituent genes present in comparison to the experimental line.
2022-06-17T00:00:00ZOresegun, Damilola RasheedPlasmodium knowlesi is a zoonotic malaria parasite of Southeastern macaque monkeys that causes zoonotic malaria in humans. P. knowlesi is also an experimental model for malaria, and information on P. knowlesi largely stem from experimental lines first isolated >four decades ago, rather than contemporary isolates causing human infections. The experimental lines are laboratory-restricted and have become relatively genetically stagnant and free from the selection pressure that would naturally occur in nature. Within the P. knowlesi genome exist the Schizont Infected Cell Agglutination variant antigen (SICAvar) and Plasmodium knowlesi interspersed repeat (kir) multigene families significant, which are of biological and scientific interest. To provide context using contemporary clinical isolates, this project aimed to generate high-quality genome sequences using long-sequencing from clinical ‘wild-type’ samples from infected patients. This includes generating new information on variant multigene families in P. knowlesi genomes generated from clinical patient whole blood. The work presented here details a method to deplete leucocytes in thawed P. knowlesi-infected patient whole blood samples to generate parasite-enriched DNA for whole-genome sequencing, resulting in >95% human DNA reduction. The extracted DNA was sequenced with long-read sequencing technology to create de novo whole-genome assemblies. From these, two isolate genomes representing the two dimorphic clusters of P. knowlesi in clinical samples were analysed. The generated genomes are highly syntenic to the published reference genome, sharing >4500 orthologous clusters with the PKNH reference genome. However, the number of SICAvar and kir genes present in the dataset deviated from the published reference genomes of P. knowlesi. The successful generation and construction of these patient genomes aid further interrogation of the contemporary P. knowlesi genome, with a focus on the constituent genes present in comparison to the experimental line.Title redactedConti, Aldo Albertohttps://hdl.handle.net/10023/271792023-07-01T02:02:32Z2022-06-17T00:00:00ZAbstract redacted
2022-06-17T00:00:00ZConti, Aldo AlbertoAbstract redactedRevealing novel insight in clear cell renal cell carcinoma through high-plex and machine learning toolsDe Filippis, Raffaelehttps://hdl.handle.net/10023/271042024-03-13T12:35:17Z2022-11-29T00:00:00ZClear Cell Renal Cell Carcinoma (ccRCC) is the most common form of kidney cancer and its
incidence is constantly increasing. Although immunotherapy has shown promising results, the
only current curative method is ablative surgery, and recurrence is observed in about one third
of cases. Moreover, patient prognosis drops significantly with metastatic disease. Current
prognostic tools such as Leibovich Score (LS) aim to predict the risk of recurrence by stratifying
patients into high, low, and intermediate risk groups. However, this algorithm only takes
into account morphological features of the tumour, such as tumour stage and nuclear grade,
while it does not consider the vast molecular milieu present in the tumour microenvironment
(TME). Furthermore, morphological features are manually assessed by pathologists and are
therefore subject to inter- and intra- observer variability. ccRCC TME is complex and heterogeneous,
consisting of cell subtypes and molecular mechanisms which may either favour or
prevent disease progression and metastatic spread. In this thesis, the author focused on four
main molecular mechanisms: immune evasion, T cell exhaustion, epithelial-to-mesenchymal
transition (EMT) and cancer stem-like cells (CSCs). Multiplex immunofluorescence (mIF) and
GeoMx digital spatial profiling (DSP) by NanoString technology have been used on 150 ccRCC
tissue microarrays (TMA) and whole slides (WS) in order to investigate the prognostic role of
more than 160 markers. mRNA was also extracted from primary and metastatic tissues from
a subset of the cohort to evaluate the expression of 750 genes using the NanoString nCounter
technology. Machine learning-based image analysis software were used to detect and quantify
these markers, their co-expression at single cell level, and their spatial relationship. Moreover,
some markers were chosen to better stratify patients at intermediate LS risk, and increase
LS accuracy. To conclude, a semi-automated method was developed in order to investigate
the ccRCC TME, reduce observer bias, and increase patients’ stratification, facilitating
personalised therapy.
2022-11-29T00:00:00ZDe Filippis, RaffaeleClear Cell Renal Cell Carcinoma (ccRCC) is the most common form of kidney cancer and its
incidence is constantly increasing. Although immunotherapy has shown promising results, the
only current curative method is ablative surgery, and recurrence is observed in about one third
of cases. Moreover, patient prognosis drops significantly with metastatic disease. Current
prognostic tools such as Leibovich Score (LS) aim to predict the risk of recurrence by stratifying
patients into high, low, and intermediate risk groups. However, this algorithm only takes
into account morphological features of the tumour, such as tumour stage and nuclear grade,
while it does not consider the vast molecular milieu present in the tumour microenvironment
(TME). Furthermore, morphological features are manually assessed by pathologists and are
therefore subject to inter- and intra- observer variability. ccRCC TME is complex and heterogeneous,
consisting of cell subtypes and molecular mechanisms which may either favour or
prevent disease progression and metastatic spread. In this thesis, the author focused on four
main molecular mechanisms: immune evasion, T cell exhaustion, epithelial-to-mesenchymal
transition (EMT) and cancer stem-like cells (CSCs). Multiplex immunofluorescence (mIF) and
GeoMx digital spatial profiling (DSP) by NanoString technology have been used on 150 ccRCC
tissue microarrays (TMA) and whole slides (WS) in order to investigate the prognostic role of
more than 160 markers. mRNA was also extracted from primary and metastatic tissues from
a subset of the cohort to evaluate the expression of 750 genes using the NanoString nCounter
technology. Machine learning-based image analysis software were used to detect and quantify
these markers, their co-expression at single cell level, and their spatial relationship. Moreover,
some markers were chosen to better stratify patients at intermediate LS risk, and increase
LS accuracy. To conclude, a semi-automated method was developed in order to investigate
the ccRCC TME, reduce observer bias, and increase patients’ stratification, facilitating
personalised therapy.Targeting mitochondrial metabolism and alternative polyadenylation in acute myeloid leukaemia with 3'-deoxyadenosineShahid, Muhammed Akbarhttps://hdl.handle.net/10023/270782023-03-14T11:59:31Z2022-11-29T00:00:00ZAbstract redacted
2022-11-29T00:00:00ZShahid, Muhammed AkbarAbstract redactedTitle redactedIoannou, Chrysohttps://hdl.handle.net/10023/270752023-07-01T02:01:04Z2022-11-29T00:00:00ZAbstract redacted
2022-11-29T00:00:00ZIoannou, ChrysoAbstract redactedWomen's experiences of mammography : fresh insights and novel measuresWhelehan, Patsyhttps://hdl.handle.net/10023/255182022-06-14T02:08:19Z2022-06-17T00:00:00ZIntroduction:
Breast cancer is an important health problem with nearly 56,000 new invasive cases yearly in the UK. It is therefore the subject of a screening programme with mammography as the test.
Screening programme effectiveness depends partly on acceptability of the test but mammography is not always acceptable to patients.
This work aimed to improve upon current understandings of the impact of pain in mammography, and of the examination experience more broadly.
Objectives:
1. To determine the relationship between mammography pain and repeat participation in breast screening;
2. To explore the contemporary experience of mammography in depth, from both patient and practitioner perspectives;
3. To develop and validate measures of patient experience in mammography.
Methods:
1. A systematic review; 2. a qualitative interview study with Framework data management and thematic analysis; 3. an instrument development and measuring and modelling study incorporating the Rasch model.
Findings:
Painful mammography was the reason given by 11-46% of non-reattenders. Meta-analysis of a subset of studies showed a relative risk of non-reattendance after pain of 1.34 [95% CI 0.94-1.91].
Qualitative findings emphasised the importance of compassionate care and highlighted challenges practitioners face in providing it.
Measures of adverse positioning and compassionate care in mammography were developed and validated, although further refinements are needed. Additional measures included general service quality and pain predisposition.
In preliminary statistical analyses, mammography pain was associated with score on the pain predisposition measure. Compassionate care score was associated with general service quality score and showed some variation by mammographer.
Conclusions/recommendations:
Improved information and support interventions are required for women attending mammography for the first time and/or with high scores on the pain predisposition measure. An educational intervention to optimise compassionate care in mammography should be developed and tested, using a refined version of the compassionate care measure. The adverse positioning measure should be expanded and further validated.
2022-06-17T00:00:00ZWhelehan, PatsyIntroduction:
Breast cancer is an important health problem with nearly 56,000 new invasive cases yearly in the UK. It is therefore the subject of a screening programme with mammography as the test.
Screening programme effectiveness depends partly on acceptability of the test but mammography is not always acceptable to patients.
This work aimed to improve upon current understandings of the impact of pain in mammography, and of the examination experience more broadly.
Objectives:
1. To determine the relationship between mammography pain and repeat participation in breast screening;
2. To explore the contemporary experience of mammography in depth, from both patient and practitioner perspectives;
3. To develop and validate measures of patient experience in mammography.
Methods:
1. A systematic review; 2. a qualitative interview study with Framework data management and thematic analysis; 3. an instrument development and measuring and modelling study incorporating the Rasch model.
Findings:
Painful mammography was the reason given by 11-46% of non-reattenders. Meta-analysis of a subset of studies showed a relative risk of non-reattendance after pain of 1.34 [95% CI 0.94-1.91].
Qualitative findings emphasised the importance of compassionate care and highlighted challenges practitioners face in providing it.
Measures of adverse positioning and compassionate care in mammography were developed and validated, although further refinements are needed. Additional measures included general service quality and pain predisposition.
In preliminary statistical analyses, mammography pain was associated with score on the pain predisposition measure. Compassionate care score was associated with general service quality score and showed some variation by mammographer.
Conclusions/recommendations:
Improved information and support interventions are required for women attending mammography for the first time and/or with high scores on the pain predisposition measure. An educational intervention to optimise compassionate care in mammography should be developed and tested, using a refined version of the compassionate care measure. The adverse positioning measure should be expanded and further validated.Mitsugumin 23 is a putative zinc regulated sarcoplasmic reticulum calcium leak channelDorward, Amyhttps://hdl.handle.net/10023/244092023-06-20T02:05:33Z2022-06-17T00:00:00ZCardiac ion homeostasis is vital for efficient cardiac function. Intracellular Ca²⁺ dyshomeostasis and sarcoplasmic reticulum (SR) Ca²⁺ leak are considered hallmarks of heart failure. Disrupted intracellular Zn²⁺ signalling is also prevalent in heart failure, with raised Zn²⁺ levels observed in cardiomyocytes under ischaemic conditions. Adverse effects of elevated Zn²⁺ levels on cardiac function are widely reported, including reduced contractile force and aberrant Ca²⁺ handling.
The molecular mechanisms linking dysregulated Zn²⁺ and Ca²⁺ signalling remain poorly understood. MG23 is a newly identified, Ca²⁺-permeable cation channel located on the SR/endoplasmic reticulum. Recently, the activity of MG23 was shown to be modulated by pathological [Zn²⁺].
The aim of this project was to investigate the role of MG23 as a Zn²⁺-regulated Ca²⁺ leak channel and to determine how altered [Zn²⁺] shapes intracellular Ca²⁺ dynamics.
Using isolated mouse cardiomyocytes, this study showed that MG23 protein expression increased following hypoxia (≤ 1% O₂; 3-24 hours). Live cell imaging demonstrated that intracellular Zn²⁺ levels are elevated in cells exposed to hypoxia, coinciding with a significant reduction in SR Ca²⁺ levels. Decreased SR Ca²⁺ was not observed following treatment with Zn²⁺-chelator TPEN at early hypoxic time points (3 hours). Strikingly, decreased SR Ca²⁺ content was not observed in cardiomyocytes isolated from Mg23-KO hearts until 24 hours hypoxia. This provides the first evidence that MG23 activity is regulated by Zn²⁺ leading to increased SR Ca²⁺ leak.
In heart failure, intracellular [Zn²⁺] is elevated to levels that increase MG23 activity. This study reveals that Zn²⁺ modulation of MG23 occurs across multiple species including mouse and human. Glutamic acid residue 79 in human MG23 was identified as a potential site for controlling Zn²⁺ modulation of channel activity. MG23 may therefore be a novel target in the design of therapeutic interventions for treatment of heart failure where SR Ca²⁺ leak is exacerbated.
2022-06-17T00:00:00ZDorward, AmyCardiac ion homeostasis is vital for efficient cardiac function. Intracellular Ca²⁺ dyshomeostasis and sarcoplasmic reticulum (SR) Ca²⁺ leak are considered hallmarks of heart failure. Disrupted intracellular Zn²⁺ signalling is also prevalent in heart failure, with raised Zn²⁺ levels observed in cardiomyocytes under ischaemic conditions. Adverse effects of elevated Zn²⁺ levels on cardiac function are widely reported, including reduced contractile force and aberrant Ca²⁺ handling.
The molecular mechanisms linking dysregulated Zn²⁺ and Ca²⁺ signalling remain poorly understood. MG23 is a newly identified, Ca²⁺-permeable cation channel located on the SR/endoplasmic reticulum. Recently, the activity of MG23 was shown to be modulated by pathological [Zn²⁺].
The aim of this project was to investigate the role of MG23 as a Zn²⁺-regulated Ca²⁺ leak channel and to determine how altered [Zn²⁺] shapes intracellular Ca²⁺ dynamics.
Using isolated mouse cardiomyocytes, this study showed that MG23 protein expression increased following hypoxia (≤ 1% O₂; 3-24 hours). Live cell imaging demonstrated that intracellular Zn²⁺ levels are elevated in cells exposed to hypoxia, coinciding with a significant reduction in SR Ca²⁺ levels. Decreased SR Ca²⁺ was not observed following treatment with Zn²⁺-chelator TPEN at early hypoxic time points (3 hours). Strikingly, decreased SR Ca²⁺ content was not observed in cardiomyocytes isolated from Mg23-KO hearts until 24 hours hypoxia. This provides the first evidence that MG23 activity is regulated by Zn²⁺ leading to increased SR Ca²⁺ leak.
In heart failure, intracellular [Zn²⁺] is elevated to levels that increase MG23 activity. This study reveals that Zn²⁺ modulation of MG23 occurs across multiple species including mouse and human. Glutamic acid residue 79 in human MG23 was identified as a potential site for controlling Zn²⁺ modulation of channel activity. MG23 may therefore be a novel target in the design of therapeutic interventions for treatment of heart failure where SR Ca²⁺ leak is exacerbated.Investigation of novel biomarkers of tuberculosis (TB) treatment response in clinical trials and clinical practiceDombay, Evelinhttps://hdl.handle.net/10023/241102021-10-11T15:54:44Z2021-11-30T00:00:00Z2021-11-30T00:00:00ZDombay, EvelinMonitoring tuberculosis treatment response using molecular techniquesFarmer, Eoghanhttps://hdl.handle.net/10023/239832023-12-01T03:06:34Z2019-12-03T00:00:00ZThis study looks to monitor tuberculosis treatment response using molecular
techniques. An assay for the detection and enumeration of Mycobacterium tuberculosis
already existed in the form of the Mycobacterial Load Assay (MBL). This utilised reverse
transcriptase quantitative polymerase chain reaction (RT-qPCR) to detect M.
tuberculosis 16S ribosomal RNA (rRNA) and thereby quantify bacillary loads in patient
sputa. By measuring labile RNA the assay was thought to only measure viable bacilli.
However, unpublished data from the Gillespie lab suggested that 16S rRNA remains
stable even once cell are non-viable. Two new markers were sought to represent the
viable bacilli: M. tuberculosis precursor 16S rRNA (pre-16S rRNA) and transfer-
messenger RNA (tm-RNA).
Both of these novel biomarkers were chosen because of their complex secondary
structures giving them increased stability allowing for their detection in adverse
environments.
Development and of a multiplex assay using the same messenger RNA (mRNA) phyB
internal control utilised by the MBL assay, then the fielding testing of these multiplex
assays was performed with the subsequent failure of the phyB control.
The internal control was then redesigned to be more robust and reproducible
utilising a novel M. marinum control. The new multiplex assays with 16S rRNA, pre-16S
rRNA and tm-RNA with the M. marinum internal control were then tested on 520 patient
samples to demonstrate that the assays could be used for monitoring treatment
response.
2019-12-03T00:00:00ZFarmer, EoghanThis study looks to monitor tuberculosis treatment response using molecular
techniques. An assay for the detection and enumeration of Mycobacterium tuberculosis
already existed in the form of the Mycobacterial Load Assay (MBL). This utilised reverse
transcriptase quantitative polymerase chain reaction (RT-qPCR) to detect M.
tuberculosis 16S ribosomal RNA (rRNA) and thereby quantify bacillary loads in patient
sputa. By measuring labile RNA the assay was thought to only measure viable bacilli.
However, unpublished data from the Gillespie lab suggested that 16S rRNA remains
stable even once cell are non-viable. Two new markers were sought to represent the
viable bacilli: M. tuberculosis precursor 16S rRNA (pre-16S rRNA) and transfer-
messenger RNA (tm-RNA).
Both of these novel biomarkers were chosen because of their complex secondary
structures giving them increased stability allowing for their detection in adverse
environments.
Development and of a multiplex assay using the same messenger RNA (mRNA) phyB
internal control utilised by the MBL assay, then the fielding testing of these multiplex
assays was performed with the subsequent failure of the phyB control.
The internal control was then redesigned to be more robust and reproducible
utilising a novel M. marinum control. The new multiplex assays with 16S rRNA, pre-16S
rRNA and tm-RNA with the M. marinum internal control were then tested on 520 patient
samples to demonstrate that the assays could be used for monitoring treatment
response.A multi-omics approach to investigate the complex interplay between muscle-invasive bladder cancer and the host immune responseGavriel, Christos G.https://hdl.handle.net/10023/239572021-09-14T14:00:26Z2021-12-01T00:00:00ZMuscle-invasive bladder cancer (MIBC) prognosis is mainly assessed by clinical cancer stage which is codified using the Tumour-Node-Metastasis (TNM) staging system. However, recent studies have demonstrated that disease progression and thus prognosis is profoundly influenced by the immune context of the tumour microenvironment. Multiplex immunofluorescence was applied on MIBC tissue sections to capture whole slide images and quantify potential prognostic markers related to lymphocytes, macrophages, PD-L1 and tumour buds. Two independent machine learning-based methodologies were implemented and the resulting prognostic models reported that: (i) tumour budding was the most significant feature (HR=2.59, P=0.0091) for the stratification of non-metastatic patients into high or low risk of disease specific death, and (ii) the combination of image, clinical, and spatial features stratified MIBC patients into two risk groups with high statistical significance (P<1E⁻⁰⁵) and greater accuracy than the current clinical gold standard, the TNM staging system . To provide further insights into the tumour-immune microenvironment, spatially resolved differential expression of immunologically relevant proteins was quantified across entire MIBC tissues using a 31-plex spatial profiling platform. Significant alterations in the expression of proteins were identified within different compartments of the tissue related to tumour core, tumour buds, stroma and tumour infiltrating lymphocytes showing that this technology has the capability to capture immunological signatures if applied in a larger heterogeneous sample population. Lastly, to delve into the molecular causes of immune evasion by cancer cells, extracellular vesicles (EVs) were isolated by differential ultra- centrifugation from conditioned media of PD-L1 and PD-L1 knockout human bladder carcinoma cells. Co-culture assays demonstrated that EVs derived from PD-L1 bladder carcinoma cells can impair immune functions by reducing CD8 T-cell proliferation. In addition, 210 EV proteins were identified by proteomic analysis, including two newly identified proteins which are not present in known exosome databases.
2021-12-01T00:00:00ZGavriel, Christos G.Muscle-invasive bladder cancer (MIBC) prognosis is mainly assessed by clinical cancer stage which is codified using the Tumour-Node-Metastasis (TNM) staging system. However, recent studies have demonstrated that disease progression and thus prognosis is profoundly influenced by the immune context of the tumour microenvironment. Multiplex immunofluorescence was applied on MIBC tissue sections to capture whole slide images and quantify potential prognostic markers related to lymphocytes, macrophages, PD-L1 and tumour buds. Two independent machine learning-based methodologies were implemented and the resulting prognostic models reported that: (i) tumour budding was the most significant feature (HR=2.59, P=0.0091) for the stratification of non-metastatic patients into high or low risk of disease specific death, and (ii) the combination of image, clinical, and spatial features stratified MIBC patients into two risk groups with high statistical significance (P<1E⁻⁰⁵) and greater accuracy than the current clinical gold standard, the TNM staging system . To provide further insights into the tumour-immune microenvironment, spatially resolved differential expression of immunologically relevant proteins was quantified across entire MIBC tissues using a 31-plex spatial profiling platform. Significant alterations in the expression of proteins were identified within different compartments of the tissue related to tumour core, tumour buds, stroma and tumour infiltrating lymphocytes showing that this technology has the capability to capture immunological signatures if applied in a larger heterogeneous sample population. Lastly, to delve into the molecular causes of immune evasion by cancer cells, extracellular vesicles (EVs) were isolated by differential ultra- centrifugation from conditioned media of PD-L1 and PD-L1 knockout human bladder carcinoma cells. Co-culture assays demonstrated that EVs derived from PD-L1 bladder carcinoma cells can impair immune functions by reducing CD8 T-cell proliferation. In addition, 210 EV proteins were identified by proteomic analysis, including two newly identified proteins which are not present in known exosome databases.Rapid detection of bacteraemia and antimicrobial susceptibility using a scattered light integrated collection (SLIC) deviceFalconer, Kerry Janehttps://hdl.handle.net/10023/235652021-09-03T15:09:32Z2021-07-02T00:00:00Z2021-07-02T00:00:00ZFalconer, Kerry JaneTitle redactedMartinelli, Angelahttps://hdl.handle.net/10023/235512021-07-21T14:20:51Z2021-07-02T00:00:00Z2021-07-02T00:00:00ZMartinelli, AngelaApplications of machine learning in biophotonics and laser metrologyGupta, Roopam Kumarhttps://hdl.handle.net/10023/234672023-07-07T02:04:33Z2021-07-02T00:00:00ZRecently, optical technologies have found several applications in fields including biophotonics, precision metrology and wavelength scale sensors. However, to gather statistically relevant information and analysis these methods require large amount of measurements. Current linear multivariate methods such as principal component analysis or linear discriminant analysis are not sufficient to analyze these big datasets with non-linear variability. Recently, the application of deep learning based artificial neural networks have found an upsurge in various areas of science ranging from quantum physics to evolutionary biology, providing an enhancement in the efficiency of various techniques. This thesis focuses on the applications of machine learning with the goal to enhance different aspects of biophotonics.
Firstly, this thesis explores the application machine learning to enhance the label-free characterization of cells of the immune system using Raman spectroscopy and digital holographic microscopy. The combination of deep learning with digital holographic microscopy provides a route towards a high throughput hemogram device which would be useful for the classification of clinically important immune cells with morphological similarities but different functions.
Following this, the applications of deep learning are explored in the regime of precision optical metrology for the development of a laser speckle wavemeter with a high dynamic range with an additional application for the development of a binary speckle based spectrometer.
Finally, the application of machine learning based methods are also explored to improve the sensitivity of the chirped guided mode biosensor. A comparison between the linear method of principal component analysis and direct Fano fitting is drawn which is followed by the application of multi layered perceptron for further improvement.
2021-07-02T00:00:00ZGupta, Roopam KumarRecently, optical technologies have found several applications in fields including biophotonics, precision metrology and wavelength scale sensors. However, to gather statistically relevant information and analysis these methods require large amount of measurements. Current linear multivariate methods such as principal component analysis or linear discriminant analysis are not sufficient to analyze these big datasets with non-linear variability. Recently, the application of deep learning based artificial neural networks have found an upsurge in various areas of science ranging from quantum physics to evolutionary biology, providing an enhancement in the efficiency of various techniques. This thesis focuses on the applications of machine learning with the goal to enhance different aspects of biophotonics.
Firstly, this thesis explores the application machine learning to enhance the label-free characterization of cells of the immune system using Raman spectroscopy and digital holographic microscopy. The combination of deep learning with digital holographic microscopy provides a route towards a high throughput hemogram device which would be useful for the classification of clinically important immune cells with morphological similarities but different functions.
Following this, the applications of deep learning are explored in the regime of precision optical metrology for the development of a laser speckle wavemeter with a high dynamic range with an additional application for the development of a binary speckle based spectrometer.
Finally, the application of machine learning based methods are also explored to improve the sensitivity of the chirped guided mode biosensor. A comparison between the linear method of principal component analysis and direct Fano fitting is drawn which is followed by the application of multi layered perceptron for further improvement.The shadow-shield whole-body monitor in clinical medicineHolmes, Barbara Margarethttps://hdl.handle.net/10023/219132022-01-13T10:29:40Z1968-01-01T00:00:00Z1968-01-01T00:00:00ZHolmes, Barbara MargaretPatterns of coping behaviour in depressionWaring, Anthony John Gainsboroughhttps://hdl.handle.net/10023/218992022-01-06T16:11:08Z1984-01-01T00:00:00ZPrevious literature relating the occurrence of stressful life events to the onset of depression is reviewed together with that which discusses the range of behaviour which people habitually deploy against such depression. The study explored the proposition that certain personality characteristics would influence the pattern of behaviour shown by individuals responding to stressful situations and would therefore determine their susceptibility to reactive depression.
24 subjects, from each of three experimental groups (normals, psychiatric controls and depressives) were asked to describe their responses to a series of 6 imagined stressful events and to the condition of feeling depressed itself. It was hypothesised that internal subjects (as defined by the Rotter Internal-External Locus of Control scale) would deploy more active problem-solving behaviour than externals who were predicted to show more defensive or passive behaviour. It was also hypothesised that the trait of internality would be stable and predictive of susceptibility to depression.
Although the predicted relationship was observed between locus of control beliefs and both patterns of responding and the amount of depressed mood, it was concluded that the external beliefs could be regarded as being co-determined with the depressive affect, rather than preceding and causing it. Some evidence was found for interactions between the nature of the stressful event and the nature of the individual, as determinants of the patterns of responding elicited. The nature of such interactions was discussed in the light of current theories of depression.
1984-01-01T00:00:00ZWaring, Anthony John GainsboroughPrevious literature relating the occurrence of stressful life events to the onset of depression is reviewed together with that which discusses the range of behaviour which people habitually deploy against such depression. The study explored the proposition that certain personality characteristics would influence the pattern of behaviour shown by individuals responding to stressful situations and would therefore determine their susceptibility to reactive depression.
24 subjects, from each of three experimental groups (normals, psychiatric controls and depressives) were asked to describe their responses to a series of 6 imagined stressful events and to the condition of feeling depressed itself. It was hypothesised that internal subjects (as defined by the Rotter Internal-External Locus of Control scale) would deploy more active problem-solving behaviour than externals who were predicted to show more defensive or passive behaviour. It was also hypothesised that the trait of internality would be stable and predictive of susceptibility to depression.
Although the predicted relationship was observed between locus of control beliefs and both patterns of responding and the amount of depressed mood, it was concluded that the external beliefs could be regarded as being co-determined with the depressive affect, rather than preceding and causing it. Some evidence was found for interactions between the nature of the stressful event and the nature of the individual, as determinants of the patterns of responding elicited. The nature of such interactions was discussed in the light of current theories of depression.Development of a vaccine against AIDS based on SIV TatDiassiti, Angelinahttps://hdl.handle.net/10023/218802021-11-17T10:01:23Z2003-01-01T00:00:00ZTat protein (Trans Activator of Transcription) is essential for efficient lentiviral transcription and completion of a lytic infection. During lentiviral infection, Tat is found both inside cells and in the extracellular medium, and extracellular Tat is responsible for some disease symptoms and toxicity during lentiviral infection. The mode of action of Tat makes it a good target for immunisation that would generate both humoral and cellular immune responses, while specific interdiction of the extracellular protein could alleviate some deleterious phenomena attributed to Tat. In the course of this study, the immunogenic potential of recombinant Tat protein from SIVmac32H(J5) was evaluated in BalbC mice and in Rhesus macaque monkeys. Recombinant Tat was initially expressed in very low amounts in E. coli, but optimisation of the Tat coding sequence for translation in the bacterial host significantly improved protein expression. Aiming to purify Tat on the basis of the affinity tag Pk (engineered on the recombinant Tat protein), a method for Pk-affinity purification was successfully developed and is available for general use. When evaluated in animal immunisation studies, Tat protein was shown to be immunogenic in the absence of a carrier or adjuvant. Furthermore, Tat generated immune responses to poorly immunogenic proteins physically linked to it, with evidence for Tₕ1-type responses in mice. There was even a suggestion that Tat was modifying the established function of the adjuvant alum towards the development of antigen-specific Tₕ1-type responses. Tat showed potential as an antigen in a lentiviral vaccine that would induce antibody and Tₕ1 responses. Furthermore, Tat being able to generate T ₕ1- type responses to co-administered antigens would be a very useful antigen carrier to generate immunity against pathogens that are cleared by Tₕ1 -based immunity.
2003-01-01T00:00:00ZDiassiti, AngelinaTat protein (Trans Activator of Transcription) is essential for efficient lentiviral transcription and completion of a lytic infection. During lentiviral infection, Tat is found both inside cells and in the extracellular medium, and extracellular Tat is responsible for some disease symptoms and toxicity during lentiviral infection. The mode of action of Tat makes it a good target for immunisation that would generate both humoral and cellular immune responses, while specific interdiction of the extracellular protein could alleviate some deleterious phenomena attributed to Tat. In the course of this study, the immunogenic potential of recombinant Tat protein from SIVmac32H(J5) was evaluated in BalbC mice and in Rhesus macaque monkeys. Recombinant Tat was initially expressed in very low amounts in E. coli, but optimisation of the Tat coding sequence for translation in the bacterial host significantly improved protein expression. Aiming to purify Tat on the basis of the affinity tag Pk (engineered on the recombinant Tat protein), a method for Pk-affinity purification was successfully developed and is available for general use. When evaluated in animal immunisation studies, Tat protein was shown to be immunogenic in the absence of a carrier or adjuvant. Furthermore, Tat generated immune responses to poorly immunogenic proteins physically linked to it, with evidence for Tₕ1-type responses in mice. There was even a suggestion that Tat was modifying the established function of the adjuvant alum towards the development of antigen-specific Tₕ1-type responses. Tat showed potential as an antigen in a lentiviral vaccine that would induce antibody and Tₕ1 responses. Furthermore, Tat being able to generate T ₕ1- type responses to co-administered antigens would be a very useful antigen carrier to generate immunity against pathogens that are cleared by Tₕ1 -based immunity.Health carers' and young people's conceptualisations of chronic illness : an anthropological interpretation of 'Diabetes mellitus'Greene, Alexandrahttps://hdl.handle.net/10023/218362021-10-25T13:56:48Z2000-01-01T00:00:00ZYoung people with Insulin-Dependent Diabetes Mellitus (IDDM) in Scotland must learn, together with the support of professional health carers, to take responsibility, on a daily basis, for the rigorous control of diabetes in an effort to reduce the instances of long-term complications which result in severe disability and early death in the second, third and fourth decades of life. Medical research shows that diabetes management is poorest during adolescence, with health carers identifying this group as the most challenging to look after. A great deal of quantitative scientific work has been done to explore the biomedical circumstances of the disease in this age group in an effort to improve management control. However, there appears to have been little qualitative and ethnographic research on young people with diabetes in the United Kingdom. Recently, the impact of social and cultural influences on young diabetics' situations and their concordance with management has been acknowledged. I was invited to join multidisciplinary health care teams in Scotland in an effort to introduce health carers to social science perspectives and to provide some social and cultural background relating to young peoples' situations. The present study is an anthropological interpretation of relationships between young people with diabetes, aged between thirteen and twenty-five years, and professional health carers. It compares young peoples' and health carers' experiences of diabetes, together with their beliefs and expectations about the appropriate amount of support that this age group requires in coping with this chronic condition. The analytical framework of this research engages with medical anthropology and a critique of its, and social sciences', relationship with biomedicine. In particular, it focuses on medical anthropology's use of oppositional models, such as the conversion model of health care and the medicalisation critique, to analyse patient-carer interactions. Alternative, non-oppositional, models are more appropriate to diabetes ethnography, where patient-carer interdependence to overcome the difficulties of diabetes management is the central theme. The thesis also argues that there should be recognition of the equally important interdependence between medical anthropology and biomedicine - this should go some way towards bridging the differences between these contrasting disciplinary perspectives.
2000-01-01T00:00:00ZGreene, AlexandraYoung people with Insulin-Dependent Diabetes Mellitus (IDDM) in Scotland must learn, together with the support of professional health carers, to take responsibility, on a daily basis, for the rigorous control of diabetes in an effort to reduce the instances of long-term complications which result in severe disability and early death in the second, third and fourth decades of life. Medical research shows that diabetes management is poorest during adolescence, with health carers identifying this group as the most challenging to look after. A great deal of quantitative scientific work has been done to explore the biomedical circumstances of the disease in this age group in an effort to improve management control. However, there appears to have been little qualitative and ethnographic research on young people with diabetes in the United Kingdom. Recently, the impact of social and cultural influences on young diabetics' situations and their concordance with management has been acknowledged. I was invited to join multidisciplinary health care teams in Scotland in an effort to introduce health carers to social science perspectives and to provide some social and cultural background relating to young peoples' situations. The present study is an anthropological interpretation of relationships between young people with diabetes, aged between thirteen and twenty-five years, and professional health carers. It compares young peoples' and health carers' experiences of diabetes, together with their beliefs and expectations about the appropriate amount of support that this age group requires in coping with this chronic condition. The analytical framework of this research engages with medical anthropology and a critique of its, and social sciences', relationship with biomedicine. In particular, it focuses on medical anthropology's use of oppositional models, such as the conversion model of health care and the medicalisation critique, to analyse patient-carer interactions. Alternative, non-oppositional, models are more appropriate to diabetes ethnography, where patient-carer interdependence to overcome the difficulties of diabetes management is the central theme. The thesis also argues that there should be recognition of the equally important interdependence between medical anthropology and biomedicine - this should go some way towards bridging the differences between these contrasting disciplinary perspectives.Enzyme immunoassay as an analytical tool in clinical chemistryMcBain, Alasdair M.https://hdl.handle.net/10023/218242021-10-25T09:04:36Z1988-01-01T00:00:00ZImmunoassay is a technique used extensively in clinical chemistry. It is a useful technique which in its most popular form of Radioimmunoassay (RIA) uses radioactive labels. As an alternative to RIA Enzyme immunoassay (ELISA) offers the advantages of the antigen-antibody reaction without the drawbacks of using a radio label. In the work presented, ELISA was investigated as an alternative to RIA for the measurement of TSH in patients suspected of having thyroid disease. The development, performance and assessment of the assay are presented. To further develop the technique, an assay for estimating albumin in the urine of diabetic patients was developed. Again the performance and assessment are presented. The method was then used to quantitate the albumin excretion in a selected group of non-insulin dependent Type II diabetics.
1988-01-01T00:00:00ZMcBain, Alasdair M.Immunoassay is a technique used extensively in clinical chemistry. It is a useful technique which in its most popular form of Radioimmunoassay (RIA) uses radioactive labels. As an alternative to RIA Enzyme immunoassay (ELISA) offers the advantages of the antigen-antibody reaction without the drawbacks of using a radio label. In the work presented, ELISA was investigated as an alternative to RIA for the measurement of TSH in patients suspected of having thyroid disease. The development, performance and assessment of the assay are presented. To further develop the technique, an assay for estimating albumin in the urine of diabetic patients was developed. Again the performance and assessment are presented. The method was then used to quantitate the albumin excretion in a selected group of non-insulin dependent Type II diabetics.Immune profiling of the colorectal cancer microenvironment for precision prognosticsNearchou, Ines P.https://hdl.handle.net/10023/216142021-08-23T11:19:37Z2020-12-01T00:00:00ZThe tumour-node-metastasis staging system is the gold standard for colorectal cancer (CRC) patient stratification into prognostic subgroups and for treatment decision making. However, same-stage patients may have a different clinical outcome. Several features within the CRC microenvironment have previously been shown to have high prognostic significance. However, they are traditionally reported independently. This thesis aimed to assess the prognostic significance of tumour budding, lymphocytic and macrophage infiltration and desmoplastic reaction (DR), as well as their spatial inter-relationships across whole slide tissue sections through the application of automated image analysis and machine learning (ML) methodologies.
Firstly, three image analysis algorithms were developed to automatically quantify tumour buds (TBs), lymphocytic and macrophage density on immunofluorescence whole slide images of patients from Scotland (n = 170) and Japan (n = 62). Survival analysis revealed that all were highly significant prognostic factors. The prognostic value of their spatial inter-relationships was also assessed, and results revealed that a low number of lymphocytes within 50μm of TBs was associated with reduced disease-specific survival.
Secondly, ML algorithms were used for the development of two novel prognostic risk models: the tumour bud-immuno spatial index (TBISI) and the spatial immuno-oncology index (SIOI). The TBISI, which integrated TBs, lymphocytic infiltration and their spatial inter-relationship, was shown to be more accurate in patient stratification than any of the features in isolation or pT stage. The SIOI, which derived from integrating lymphocytic infiltration, the spatial association of lymphocytes and TBs and CD68⁺/CD163⁺ macrophage ratio, identified a subpopulation of patients who exhibit 100% survival over a 11.8-year follow-up period. All the aforementioned findings were confirmed in independent validation cohorts.
Finally, a novel ML algorithm for the automatic and standardised classification of DR on stage II and III CRC patients (n = 528) was developed. The algorithm was shown to successfully classify DR on unseen whole slide images. Survival analysis results revealed that the ML classifier had a higher prognostic significance than manually assessed DR.
In conclusion this thesis demonstrates how the use of automated image analysis can be successfully used for the standardised and reproducible assessment of various features and their inter-relationships within the complex tumour microenvironment. Additionally, it demonstrates how through ML approaches it is possible to develop novel combinatorial prognostic models which improve the prognostic accuracy in CRC.
2020-12-01T00:00:00ZNearchou, Ines P.The tumour-node-metastasis staging system is the gold standard for colorectal cancer (CRC) patient stratification into prognostic subgroups and for treatment decision making. However, same-stage patients may have a different clinical outcome. Several features within the CRC microenvironment have previously been shown to have high prognostic significance. However, they are traditionally reported independently. This thesis aimed to assess the prognostic significance of tumour budding, lymphocytic and macrophage infiltration and desmoplastic reaction (DR), as well as their spatial inter-relationships across whole slide tissue sections through the application of automated image analysis and machine learning (ML) methodologies.
Firstly, three image analysis algorithms were developed to automatically quantify tumour buds (TBs), lymphocytic and macrophage density on immunofluorescence whole slide images of patients from Scotland (n = 170) and Japan (n = 62). Survival analysis revealed that all were highly significant prognostic factors. The prognostic value of their spatial inter-relationships was also assessed, and results revealed that a low number of lymphocytes within 50μm of TBs was associated with reduced disease-specific survival.
Secondly, ML algorithms were used for the development of two novel prognostic risk models: the tumour bud-immuno spatial index (TBISI) and the spatial immuno-oncology index (SIOI). The TBISI, which integrated TBs, lymphocytic infiltration and their spatial inter-relationship, was shown to be more accurate in patient stratification than any of the features in isolation or pT stage. The SIOI, which derived from integrating lymphocytic infiltration, the spatial association of lymphocytes and TBs and CD68⁺/CD163⁺ macrophage ratio, identified a subpopulation of patients who exhibit 100% survival over a 11.8-year follow-up period. All the aforementioned findings were confirmed in independent validation cohorts.
Finally, a novel ML algorithm for the automatic and standardised classification of DR on stage II and III CRC patients (n = 528) was developed. The algorithm was shown to successfully classify DR on unseen whole slide images. Survival analysis results revealed that the ML classifier had a higher prognostic significance than manually assessed DR.
In conclusion this thesis demonstrates how the use of automated image analysis can be successfully used for the standardised and reproducible assessment of various features and their inter-relationships within the complex tumour microenvironment. Additionally, it demonstrates how through ML approaches it is possible to develop novel combinatorial prognostic models which improve the prognostic accuracy in CRC.A role for mitsugumin 23 in cardiac sarcoplasmic reticulum calcium leakRobertson, Gavin B.https://hdl.handle.net/10023/190642021-03-15T11:12:26Z2019-06-28T00:00:00ZCarefully controlled intracellular Ca²⁺-release is essential for maintenance of normal
cardiac function. In failing hearts, dysregulated Zn²⁺-homeostasis is associated with
disrupted intracellular Ca²⁺-homeostasis, however the underlying molecular
mechanisms remain elusive. Mitsugumin 23 (MG23) is a newly identified SR Ca²⁺-
permeable ion channel found in sarcoplasmic reticulum (SR) membranes, challenging
understanding that RyR2 is the only SR Ca²⁺-release channel. The major hypothesis of
this thesis is that MG23 is a Zn²⁺-regulated SR Ca²⁺-leak channel, and that this function
plays a key role in disease progression mechanisms in heart failure. The aim of this study
was to investigate at the molecular level how Zn²⁺ regulates MG23-channel function and
how this shapes intracellular Ca²⁺-dynamics in the failing heart.
Using single-channel electrophysiological techniques, this study demonstrated that
RyR2 is not the only SR Ca²⁺-channel directly modulated by Zn²⁺. Pathophysiological
(≥1 nM) levels of cytosolic Zn²⁺ potentiated MG23-channel activity, with the current
amplitude of MG23-channel openings found to be consistent to that previously reported
as RyR2 sub-conductance gating. In bilayer experiments using SR vesicles isolated from
MG23 knock-out mice, RyR2 sub-conductance gating was never observed. These data
reveal that following elevation of Zn²⁺ in heart failure, RyR2 sub-conductance gating does
not occur but rather MG23-channel gating becomes exacerbated likely resulting in
cardiac dysfunction.
Live-cell Ca²⁺-imaging in isolated mouse cardiomyocytes demonstrated that MG23
function as a Ca²⁺-leak channel is an important determinant of SR Ca²⁺ content. In
cardiomyocytes exposed to ischaemia, MG23-mediated Ca²⁺-leak provided
cardioprotection against SR Ca²⁺-store overload-induced spontaneous Ca²⁺-release.
Increased MG23 protein expression observed following prolonged exposure to hypoxia
may contribute to altered Ca²⁺-dynamics associated with cardiac remodelling in chronic
heart failure. This study also provided the first demonstration of the Zn²⁺-permeability of
MG23, suggesting that MG23 can mediate SR Zn²⁺-flux following redistribution of ionic
balance across the SR membrane during EC-coupling or following disruption of
homeostatic mechanisms.
Taken together these findings identify a key role for MG23 as a SR Ca²⁺-leak channel in
both normal and disrupted cardiac function, highlighting MG23 as a potential therapeutic
target in the treatment of the failing heart.
2019-06-28T00:00:00ZRobertson, Gavin B.Carefully controlled intracellular Ca²⁺-release is essential for maintenance of normal
cardiac function. In failing hearts, dysregulated Zn²⁺-homeostasis is associated with
disrupted intracellular Ca²⁺-homeostasis, however the underlying molecular
mechanisms remain elusive. Mitsugumin 23 (MG23) is a newly identified SR Ca²⁺-
permeable ion channel found in sarcoplasmic reticulum (SR) membranes, challenging
understanding that RyR2 is the only SR Ca²⁺-release channel. The major hypothesis of
this thesis is that MG23 is a Zn²⁺-regulated SR Ca²⁺-leak channel, and that this function
plays a key role in disease progression mechanisms in heart failure. The aim of this study
was to investigate at the molecular level how Zn²⁺ regulates MG23-channel function and
how this shapes intracellular Ca²⁺-dynamics in the failing heart.
Using single-channel electrophysiological techniques, this study demonstrated that
RyR2 is not the only SR Ca²⁺-channel directly modulated by Zn²⁺. Pathophysiological
(≥1 nM) levels of cytosolic Zn²⁺ potentiated MG23-channel activity, with the current
amplitude of MG23-channel openings found to be consistent to that previously reported
as RyR2 sub-conductance gating. In bilayer experiments using SR vesicles isolated from
MG23 knock-out mice, RyR2 sub-conductance gating was never observed. These data
reveal that following elevation of Zn²⁺ in heart failure, RyR2 sub-conductance gating does
not occur but rather MG23-channel gating becomes exacerbated likely resulting in
cardiac dysfunction.
Live-cell Ca²⁺-imaging in isolated mouse cardiomyocytes demonstrated that MG23
function as a Ca²⁺-leak channel is an important determinant of SR Ca²⁺ content. In
cardiomyocytes exposed to ischaemia, MG23-mediated Ca²⁺-leak provided
cardioprotection against SR Ca²⁺-store overload-induced spontaneous Ca²⁺-release.
Increased MG23 protein expression observed following prolonged exposure to hypoxia
may contribute to altered Ca²⁺-dynamics associated with cardiac remodelling in chronic
heart failure. This study also provided the first demonstration of the Zn²⁺-permeability of
MG23, suggesting that MG23 can mediate SR Zn²⁺-flux following redistribution of ionic
balance across the SR membrane during EC-coupling or following disruption of
homeostatic mechanisms.
Taken together these findings identify a key role for MG23 as a SR Ca²⁺-leak channel in
both normal and disrupted cardiac function, highlighting MG23 as a potential therapeutic
target in the treatment of the failing heart.All-optical assay to study biological neural networksAfshar Saber, Wardiyahttps://hdl.handle.net/10023/190512021-03-09T14:27:27Z2019-06-28T00:00:00ZAs life span increases, neurodegenerative diseases such as dementia, Parkinson’s
disease, Huntington’s disease, amyotrophic lateral sclerosis become an emerging
problem in modern society. In particular Alzheimer’s disease (AD), characterized by
a progressive cognitive impairment and memory loss, is the dominant cause of disability
in people aged over 60. Due to the lack of accurate models, understanding the disease
mechanisms and developing a cure for AD remains challenging. However, a novel
approach based on human induced pluripotent stem cell (iPSC) technology may offer an
opportunity to overcome the limitations of the current models. These cells obtained by
reprogramming patient’s somatic cells such as fibroblasts can be differentiated in vitro
into various types of neural cells which further develop complex networks. To explore
these heterogeneous neural networks, it is often critical to understand the activity of
multiple neurons and how they communicate with each other. The work presented in
this thesis focuses on the development of the first molecular optogenetic tool called
OptoCaMP used in an all-optical assay enabling simultaneous stimulation and calcium
imaging of a large population of neurons with a single-cell readout. This assay was
further adapted to study the spread of excitation in a network thus allowing the
quantification of its connectivity. The application of this assay in conditions where the
neuronal connectivity was enhanced or decreased successfully demonstrated its
sensitivity to changes in connectivity. This assay together with the iPSC technology bring
the promise to greatly improve disease models studies and drug screening platforms.
2019-06-28T00:00:00ZAfshar Saber, WardiyaAs life span increases, neurodegenerative diseases such as dementia, Parkinson’s
disease, Huntington’s disease, amyotrophic lateral sclerosis become an emerging
problem in modern society. In particular Alzheimer’s disease (AD), characterized by
a progressive cognitive impairment and memory loss, is the dominant cause of disability
in people aged over 60. Due to the lack of accurate models, understanding the disease
mechanisms and developing a cure for AD remains challenging. However, a novel
approach based on human induced pluripotent stem cell (iPSC) technology may offer an
opportunity to overcome the limitations of the current models. These cells obtained by
reprogramming patient’s somatic cells such as fibroblasts can be differentiated in vitro
into various types of neural cells which further develop complex networks. To explore
these heterogeneous neural networks, it is often critical to understand the activity of
multiple neurons and how they communicate with each other. The work presented in
this thesis focuses on the development of the first molecular optogenetic tool called
OptoCaMP used in an all-optical assay enabling simultaneous stimulation and calcium
imaging of a large population of neurons with a single-cell readout. This assay was
further adapted to study the spread of excitation in a network thus allowing the
quantification of its connectivity. The application of this assay in conditions where the
neuronal connectivity was enhanced or decreased successfully demonstrated its
sensitivity to changes in connectivity. This assay together with the iPSC technology bring
the promise to greatly improve disease models studies and drug screening platforms.Computational image analysis in clear cell renal cell carcinomaUm, In Hwahttps://hdl.handle.net/10023/189632021-04-07T10:09:43Z2019-12-03T00:00:00ZBackground: In the UK, kidney cancer is the most lethal urologic cancer whose
major subtype is renal cell carcinoma (RCC). Surgical resection is the first line of the
treatment for renal cell carcinoma (RCC). A number of different integrated staging
systems such as UISS, SSIGN and Leibovich score, has been introduced and utilised in
clinic as a prognostic tool or as an inclusion criterion of clinical trials. Among them,
Leibovich score has been widely utilised in the UK to predict the likelihood of disease
free survival for clear cell renal cell carcinoma (ccRCC). However, its prediction rate
of disease relapse free for 5 years after surgery varies from 97% (low risk) to 31%
(high risk) which might lead to inclusion of some ccRCC patients, who would not recur,
into a clinical trial. Therefore, we aim to improve the prediction power of recurrence
free (specificity) in localised clear cell renal cell carcinoma (ccRCC) patients, by either
modifying Leibovich score with more precise and accurate measurement of ccRCC
nuclear morphological features or by improving currently available Leibovich score
with the features measured from the chromatin marker colocalisation status,
chromatin marker Haralick texture features, and the tumour microenvironment using
computational image analysis.
Methods: To modify Leibovich score by replacing manual Fuhrman’s nuclear grade
with the computational image analysis measurement of the nuclear morphological
features, digitised images from haematoxylin and eosin stained slides were utilised.
For the chromatin marker (H3K9me3, H3K4me3 and HP1α) colocalisation analysis,
Haralick texture analysis and tumour microenvironment marker (CD105 and CD3)
analysis, the multiplexed immunofluorescence (IF) was performed and IF images
were utilised. The image analysis was performed by using Definiens Tissue studio®
(Definiens AG, Munich, Germany) and the Developer platform. Moreover, a novel
statistical model was developed using AUCp (partial area under the curve) function
in R studio, which defines the range of specificity between 1 and 0.8 on the basis of
the binomial GLM (Generalised linear model) framework with GAM-SALSA
(Generalised Additive Models - Spatially adaptive local smoothing algorithm) as a
calibration tool. In order to avoid the overfitting problem, 5-fold cross validation with
100 times repetition was also added in the analysis.
Results: Firstly, our statistical model replaced Fuhrman’s nuclear grade with ‘mean
perimeter’, which was named ‘Modified Leibovich algorithm’. The modified Leibovich
algorithm improved its overall specificity 0.86 (80 out of 93 cases) from 0.76 (71 out
of 93) from the classic L score in the Scottish training cohort. In particular, the most
increase in specificity was seen in Leibovich score 5 and 6, which were 57% and 40%,
respectively. The modified Leibovich algorithm also increased overall specificity up to
0.94 (141 out of 150 cases), compared to the classic (original) Leibovich score whose
specificity was 0.84 (126 out of 150 cases) in a Singaporean validation cohort.
Moreover, specificity was dramatically increased in Leibovich score 5 from 0% to 92%.
Secondly, the chromatin marker colocalisation feature significantly improved the specificity of the classic and partial Leibovich score up to 0.98 in overall. In particular,
the specificity of the cases in Leibovich score 4, 5 and 6 was improved up to 100%.
However, the chromatin marker Haralick texture features did not improve the
specificity of the classic and partial Leibovich score as much as the chromatin marker
colocalisation features.
Thirdly, the tumour microenvironment features such as the density and the spatial
distances of CD105 positive blood vessels and CD3 positive mature T lymphocytes
augmented the specificity of the classic and partial Leibovich score up to 0.93. In
particular, it improved the specificity up to 92% in Leibovich score 5 compared to the
classic Leibovich score.
Conclusions: Computational image analysis enabled to measure such various
ranges of features not only in tumour cells, but also in tumour microenvironment. In
this study, ccRCC tumour cell nuclear morphological features, chromatin marker
colocalisation feature, chromatin Haralick texture features and tumour
microenvironment features were visualised by the multiplexed immunofluorescence
and measured by the Tissue studio and developer software: this cannot be done
manually. The data from this analysis significantly augmented the specificity of the
currently available prognostic tool, Leibovich score, in clinic. In particular, the very
last final model developed by combining features of the chromatin marker colocalisation (‘Average.HP1a.Intensity..H3K4_HP1a.Overlap.’ and ‘Manders.Coefficient.Nuclei..H3K4.HP1a..M2’) and tumour microenvironment (‘Mean.CD3.Area.percentage.of.All.Tissue’ and ‘Mean.No..of.CD105’) selected along
with the classic Leibovich score, predicted 100% (93 out of 93 cases) correctly the
cases which did not experience the disease recurrence within 5 years after surgery,
while the classic Leibovich score predicted 76% (71 out of 93 cases) correctly. This
could have prevented 22 ccRCC patients not only to get unpleasant and unnecessary
treatment after nephrectomy, but also helped them having been free from the fear
of disease recurrence.
2019-12-03T00:00:00ZUm, In HwaBackground: In the UK, kidney cancer is the most lethal urologic cancer whose
major subtype is renal cell carcinoma (RCC). Surgical resection is the first line of the
treatment for renal cell carcinoma (RCC). A number of different integrated staging
systems such as UISS, SSIGN and Leibovich score, has been introduced and utilised in
clinic as a prognostic tool or as an inclusion criterion of clinical trials. Among them,
Leibovich score has been widely utilised in the UK to predict the likelihood of disease
free survival for clear cell renal cell carcinoma (ccRCC). However, its prediction rate
of disease relapse free for 5 years after surgery varies from 97% (low risk) to 31%
(high risk) which might lead to inclusion of some ccRCC patients, who would not recur,
into a clinical trial. Therefore, we aim to improve the prediction power of recurrence
free (specificity) in localised clear cell renal cell carcinoma (ccRCC) patients, by either
modifying Leibovich score with more precise and accurate measurement of ccRCC
nuclear morphological features or by improving currently available Leibovich score
with the features measured from the chromatin marker colocalisation status,
chromatin marker Haralick texture features, and the tumour microenvironment using
computational image analysis.
Methods: To modify Leibovich score by replacing manual Fuhrman’s nuclear grade
with the computational image analysis measurement of the nuclear morphological
features, digitised images from haematoxylin and eosin stained slides were utilised.
For the chromatin marker (H3K9me3, H3K4me3 and HP1α) colocalisation analysis,
Haralick texture analysis and tumour microenvironment marker (CD105 and CD3)
analysis, the multiplexed immunofluorescence (IF) was performed and IF images
were utilised. The image analysis was performed by using Definiens Tissue studio®
(Definiens AG, Munich, Germany) and the Developer platform. Moreover, a novel
statistical model was developed using AUCp (partial area under the curve) function
in R studio, which defines the range of specificity between 1 and 0.8 on the basis of
the binomial GLM (Generalised linear model) framework with GAM-SALSA
(Generalised Additive Models - Spatially adaptive local smoothing algorithm) as a
calibration tool. In order to avoid the overfitting problem, 5-fold cross validation with
100 times repetition was also added in the analysis.
Results: Firstly, our statistical model replaced Fuhrman’s nuclear grade with ‘mean
perimeter’, which was named ‘Modified Leibovich algorithm’. The modified Leibovich
algorithm improved its overall specificity 0.86 (80 out of 93 cases) from 0.76 (71 out
of 93) from the classic L score in the Scottish training cohort. In particular, the most
increase in specificity was seen in Leibovich score 5 and 6, which were 57% and 40%,
respectively. The modified Leibovich algorithm also increased overall specificity up to
0.94 (141 out of 150 cases), compared to the classic (original) Leibovich score whose
specificity was 0.84 (126 out of 150 cases) in a Singaporean validation cohort.
Moreover, specificity was dramatically increased in Leibovich score 5 from 0% to 92%.
Secondly, the chromatin marker colocalisation feature significantly improved the specificity of the classic and partial Leibovich score up to 0.98 in overall. In particular,
the specificity of the cases in Leibovich score 4, 5 and 6 was improved up to 100%.
However, the chromatin marker Haralick texture features did not improve the
specificity of the classic and partial Leibovich score as much as the chromatin marker
colocalisation features.
Thirdly, the tumour microenvironment features such as the density and the spatial
distances of CD105 positive blood vessels and CD3 positive mature T lymphocytes
augmented the specificity of the classic and partial Leibovich score up to 0.93. In
particular, it improved the specificity up to 92% in Leibovich score 5 compared to the
classic Leibovich score.
Conclusions: Computational image analysis enabled to measure such various
ranges of features not only in tumour cells, but also in tumour microenvironment. In
this study, ccRCC tumour cell nuclear morphological features, chromatin marker
colocalisation feature, chromatin Haralick texture features and tumour
microenvironment features were visualised by the multiplexed immunofluorescence
and measured by the Tissue studio and developer software: this cannot be done
manually. The data from this analysis significantly augmented the specificity of the
currently available prognostic tool, Leibovich score, in clinic. In particular, the very
last final model developed by combining features of the chromatin marker colocalisation (‘Average.HP1a.Intensity..H3K4_HP1a.Overlap.’ and ‘Manders.Coefficient.Nuclei..H3K4.HP1a..M2’) and tumour microenvironment (‘Mean.CD3.Area.percentage.of.All.Tissue’ and ‘Mean.No..of.CD105’) selected along
with the classic Leibovich score, predicted 100% (93 out of 93 cases) correctly the
cases which did not experience the disease recurrence within 5 years after surgery,
while the classic Leibovich score predicted 76% (71 out of 93 cases) correctly. This
could have prevented 22 ccRCC patients not only to get unpleasant and unnecessary
treatment after nephrectomy, but also helped them having been free from the fear
of disease recurrence.The neighbourhood social environment and its role in adolescent alcohol use and drinking motivesMartin, Gina Chrissyhttps://hdl.handle.net/10023/188532021-04-07T16:09:31Z2019-06-28T00:00:00ZIn Scotland, adolescent alcohol consumption represents a major public health concern.
The overarching aim of this research was to identify neighbourhood characteristics associated
with adolescent alcohol use behaviours and motivations for drinking with a focus
on the neighbourhood social environment.
A systematic review identified and synthesised studies that operationalised the
neighbourhood social environment from the adolescents' perspective. Using Scottish
Health Behaviours in School-aged Children Survey data, exploratory and confirmatory
factor analysis were conducted to derive measures of adolescents' perceptions of their
local neighbourhood and test for urban/rural invariance. Multilevel models were used
to estimate ecometric properties and generate neighbourhood scores. These measures
were then used in models to explore associations between various physical and social
conditions of the local area with adolescent alcohol use and drinking motivations. Path
analysis explored for potential mediating effects of drinking motivations on drinking
outcomes.
The findings from this thesis indicate that where adolescents live is associated
with their alcohol use behaviours and motivations. Neighbourhood social cohesion, urban/rural
status and neighbourhood deprivation may give rise to inequalities in alcohol
use. Evidence of drinking to cope as a mediator in the relationship between deprivation
and weekly alcohol use suggests that drinking as a coping strategy differs by geographic
subgroups. Findings support that targeted prevention and intervention strategies are
needed to reduce inequalities. Programmes developed to encourage coping skills should
be implemented, principally in deprived neighbourhoods and accessible small-towns.
Future research is needed to develop and assess strategies to reduce inequalities in adolescent
drinking in Scotland.
2019-06-28T00:00:00ZMartin, Gina ChrissyIn Scotland, adolescent alcohol consumption represents a major public health concern.
The overarching aim of this research was to identify neighbourhood characteristics associated
with adolescent alcohol use behaviours and motivations for drinking with a focus
on the neighbourhood social environment.
A systematic review identified and synthesised studies that operationalised the
neighbourhood social environment from the adolescents' perspective. Using Scottish
Health Behaviours in School-aged Children Survey data, exploratory and confirmatory
factor analysis were conducted to derive measures of adolescents' perceptions of their
local neighbourhood and test for urban/rural invariance. Multilevel models were used
to estimate ecometric properties and generate neighbourhood scores. These measures
were then used in models to explore associations between various physical and social
conditions of the local area with adolescent alcohol use and drinking motivations. Path
analysis explored for potential mediating effects of drinking motivations on drinking
outcomes.
The findings from this thesis indicate that where adolescents live is associated
with their alcohol use behaviours and motivations. Neighbourhood social cohesion, urban/rural
status and neighbourhood deprivation may give rise to inequalities in alcohol
use. Evidence of drinking to cope as a mediator in the relationship between deprivation
and weekly alcohol use suggests that drinking as a coping strategy differs by geographic
subgroups. Findings support that targeted prevention and intervention strategies are
needed to reduce inequalities. Programmes developed to encourage coping skills should
be implemented, principally in deprived neighbourhoods and accessible small-towns.
Future research is needed to develop and assess strategies to reduce inequalities in adolescent
drinking in Scotland.Influence of plasma fatty acids on serum albumin-metal interactions and blood clottingKatundu, Kondwani George Happyhttps://hdl.handle.net/10023/188472024-01-26T03:06:52Z2019-12-03T00:00:00ZNon-communicable diseases (NCDs) are a cause of high mortality and morbidity globally. HIV
infection has complicated the burden of NCDs further by increasing its prevalence, mostly in lowand
middle-income countries. NCDs and HIV are associated with higher plasma free fatty acids
(FFA) in plasma and are risk factors for thromboembolic events.
Human serum albumin (HSA) is a carrier of many metal ions and is also the primary transporter of
FFA in plasma. Higher concentrations of FFA in plasma and their binding to the fatty acid binding
site FA2, may elicit conformational changes that may perturb metal binding at site A. The binding
affinity of albumin to Co²⁺ and Zn²⁺ can be compromised in pathological conditions associated with
higher FFA concentrations and can influence clinical diagnostic tests such as the albumin cobaltbinding
(ACB) assay. Zn²⁺ is a key regulator of haemostasis, and the concentration of labile Zn²⁺ in
plasma is tightly regulated through binding to HSA. Abnormally high FFA concentrations can thus
allosterically disrupt the binding of Zn²⁺ to HSA and potentiate abnormal platelet aggregation. This
thesis aimed to assess the influence of elevated FFA concentrations on the interaction between
albumin and metal ions in the circulation, and how abnormal pathophysiological processes such as
thromboembolic events may be precipitated in pathological conditions especially in NCDs and HIV
infection due to the higher FFA levels.
The results of this study, using the albumin cobalt binding (ACB) assay, showed that long chain
fatty acids perturbed the binding of Co²⁺ at the multimetal binding site A, which is also the primary
binding site for Zn²⁺, in a concentration-dependent manner. These results were also supported by
isothermal titration calorimetry.
Platelet aggregation experimental results revealed that Zn²⁺, in the absence of HSA, potentiated
platelet aggregation by positively influencing the maximum and rate of aggregation responses.
Higher (supraphysiological) concentrations of added myristate, but not octanoate, positively
affected the maximum platelet aggregation responses, plausibly via allosteric Zn²⁺ switch from
albumin. The in-silico analysis of albumin crystal structures examined in this project, exposed the
disruption of the primary Zn²⁺ -binding site on albumin by long chain fatty acids, due to changes in
the distances between the specific amino acid residues forming the site. Lastly, a clinical study was conducted to investigate the FFA concentrations, albumin levels and
coagulability in HIV – infected individuals compared to controls. The results indicated that
participants with HIV infection and recently commenced on (antiretroviral therapy) ART had
subnormal levels of albumin concentration than the controls. Also, the FFA concentrations were
significantly higher in HIV – infected participants on ART for more than 6 months than the controls.
Nevertheless, the coagulability tests assessed by international normalized ratio (INR) and the
turbidity tests of plasma did not show any differences among the groups.
These study results contribute to the body of knowledge on how FFA can influence abnormal
handling of Zn²⁺ by HSA in circulation, which may precipitate platelet aggregation and increase the
risk for thromboembolic events, such as stroke, in populations at risk. Possible and relevant
suggestions on how the mishandling of Zn²⁺ by HSA may be mitigated in populations at risk have
been discussed.
2019-12-03T00:00:00ZKatundu, Kondwani George HappyNon-communicable diseases (NCDs) are a cause of high mortality and morbidity globally. HIV
infection has complicated the burden of NCDs further by increasing its prevalence, mostly in lowand
middle-income countries. NCDs and HIV are associated with higher plasma free fatty acids
(FFA) in plasma and are risk factors for thromboembolic events.
Human serum albumin (HSA) is a carrier of many metal ions and is also the primary transporter of
FFA in plasma. Higher concentrations of FFA in plasma and their binding to the fatty acid binding
site FA2, may elicit conformational changes that may perturb metal binding at site A. The binding
affinity of albumin to Co²⁺ and Zn²⁺ can be compromised in pathological conditions associated with
higher FFA concentrations and can influence clinical diagnostic tests such as the albumin cobaltbinding
(ACB) assay. Zn²⁺ is a key regulator of haemostasis, and the concentration of labile Zn²⁺ in
plasma is tightly regulated through binding to HSA. Abnormally high FFA concentrations can thus
allosterically disrupt the binding of Zn²⁺ to HSA and potentiate abnormal platelet aggregation. This
thesis aimed to assess the influence of elevated FFA concentrations on the interaction between
albumin and metal ions in the circulation, and how abnormal pathophysiological processes such as
thromboembolic events may be precipitated in pathological conditions especially in NCDs and HIV
infection due to the higher FFA levels.
The results of this study, using the albumin cobalt binding (ACB) assay, showed that long chain
fatty acids perturbed the binding of Co²⁺ at the multimetal binding site A, which is also the primary
binding site for Zn²⁺, in a concentration-dependent manner. These results were also supported by
isothermal titration calorimetry.
Platelet aggregation experimental results revealed that Zn²⁺, in the absence of HSA, potentiated
platelet aggregation by positively influencing the maximum and rate of aggregation responses.
Higher (supraphysiological) concentrations of added myristate, but not octanoate, positively
affected the maximum platelet aggregation responses, plausibly via allosteric Zn²⁺ switch from
albumin. The in-silico analysis of albumin crystal structures examined in this project, exposed the
disruption of the primary Zn²⁺ -binding site on albumin by long chain fatty acids, due to changes in
the distances between the specific amino acid residues forming the site. Lastly, a clinical study was conducted to investigate the FFA concentrations, albumin levels and
coagulability in HIV – infected individuals compared to controls. The results indicated that
participants with HIV infection and recently commenced on (antiretroviral therapy) ART had
subnormal levels of albumin concentration than the controls. Also, the FFA concentrations were
significantly higher in HIV – infected participants on ART for more than 6 months than the controls.
Nevertheless, the coagulability tests assessed by international normalized ratio (INR) and the
turbidity tests of plasma did not show any differences among the groups.
These study results contribute to the body of knowledge on how FFA can influence abnormal
handling of Zn²⁺ by HSA in circulation, which may precipitate platelet aggregation and increase the
risk for thromboembolic events, such as stroke, in populations at risk. Possible and relevant
suggestions on how the mishandling of Zn²⁺ by HSA may be mitigated in populations at risk have
been discussed.Title redactedFerguson, Sophie Grace Aliciahttps://hdl.handle.net/10023/187862021-03-18T09:43:20Z2019-06-28T00:00:00Z2019-06-28T00:00:00ZFerguson, Sophie Grace AliciaTitle redactedMcKissock, Fiona Gracehttps://hdl.handle.net/10023/187852021-03-17T10:14:50Z2019-06-28T00:00:00Z2019-06-28T00:00:00ZMcKissock, Fiona GraceExploration of the pharmacodynamic profile of Acelarin, a novel ProTide drug, in an in vitro model of ovarian cancerBré, Jenniferhttps://hdl.handle.net/10023/187732021-03-17T09:52:15Z2019-06-28T00:00:00Z2019-06-28T00:00:00ZBré, JenniferAn investigation into the relevance of dual-specificity phosphatase 6 in colorectal cancerWilliams, Hannah Louisehttps://hdl.handle.net/10023/187452021-03-05T12:13:44Z2019-06-28T00:00:00Z2019-06-28T00:00:00ZWilliams, Hannah LouiseExploring the role of Itch in human cancer and bone remodellingRead, Oliver Jameshttps://hdl.handle.net/10023/186922021-08-15T02:02:20Z2019-12-03T00:00:00ZTight control of post-translational modifications such as ubiquitination is important for cell homeostasis and dysregulation of this process is a common feature in many diseases. Itch encodes an E3 ubiquitin ligase that conjugates ubiquitin to a variety of substrates such as Jun B, PKC-θ, PLC- γ1, LATS, TXNIP and p73. In this study both transient and stable knockdown techniques (siRNA and CRISPR respectively) were utilised to explore the role of Itch in both cancer progression and bone remodelling. Transient siRNA-mediated knockdown of Itch inhibited cell viability of MiaPaCa-2 and Capan-2 cell lines by ~50% and ~60% respectively compared to both scrambled and untreated controls as determined by SRB. Although siRNA did not increase cell line sensitivity to γ-radiation, doxorubicin, and gemcitabine, it did have an additive effect on resultant survivability. CRISPR-Cas9 mediated stable Itch knockdowns in the same cell lines in contrast showed increased sensitivity to the aforementioned treatment regimens however resultant data obtained from cell survival and clonogenicity assays suggested that the CRISPR⁺ MiaPaCa-2 cells divide faster than both scrambled and parental controls. SWATH-DIA analysis was performed to look for differences in proteome between CRISPR⁺ and parental MiaPaCa-2 cells. Preliminary data based on isogenic clones suggests potential differences, but additional repeats and further validation is required. Transient Itch knockdown in peripheral blood monocytes increased their capacity to differentiate into fully matured osteoclasts ex-vivo: compared to untreated controls, si-Itch treated wells showed higher mean numbers of large TRAP⁺ cells (mean = 63 and 54 for si-Itch and untreated wells respectively) and multinucleate cells (mean = 25 and 17 for si-Itch and untreated wells respectively) in a 96-well format. Meanwhile CRISPR-mediated knockdown induced a large degree of cellular toxicity in PBMCs. This contrast between stable and transient Itch knockdown prompted discussion of the strengths and weaknesses of each technique and their suitability in different experimental contexts.
2019-12-03T00:00:00ZRead, Oliver JamesTight control of post-translational modifications such as ubiquitination is important for cell homeostasis and dysregulation of this process is a common feature in many diseases. Itch encodes an E3 ubiquitin ligase that conjugates ubiquitin to a variety of substrates such as Jun B, PKC-θ, PLC- γ1, LATS, TXNIP and p73. In this study both transient and stable knockdown techniques (siRNA and CRISPR respectively) were utilised to explore the role of Itch in both cancer progression and bone remodelling. Transient siRNA-mediated knockdown of Itch inhibited cell viability of MiaPaCa-2 and Capan-2 cell lines by ~50% and ~60% respectively compared to both scrambled and untreated controls as determined by SRB. Although siRNA did not increase cell line sensitivity to γ-radiation, doxorubicin, and gemcitabine, it did have an additive effect on resultant survivability. CRISPR-Cas9 mediated stable Itch knockdowns in the same cell lines in contrast showed increased sensitivity to the aforementioned treatment regimens however resultant data obtained from cell survival and clonogenicity assays suggested that the CRISPR⁺ MiaPaCa-2 cells divide faster than both scrambled and parental controls. SWATH-DIA analysis was performed to look for differences in proteome between CRISPR⁺ and parental MiaPaCa-2 cells. Preliminary data based on isogenic clones suggests potential differences, but additional repeats and further validation is required. Transient Itch knockdown in peripheral blood monocytes increased their capacity to differentiate into fully matured osteoclasts ex-vivo: compared to untreated controls, si-Itch treated wells showed higher mean numbers of large TRAP⁺ cells (mean = 63 and 54 for si-Itch and untreated wells respectively) and multinucleate cells (mean = 25 and 17 for si-Itch and untreated wells respectively) in a 96-well format. Meanwhile CRISPR-mediated knockdown induced a large degree of cellular toxicity in PBMCs. This contrast between stable and transient Itch knockdown prompted discussion of the strengths and weaknesses of each technique and their suitability in different experimental contexts.Title redactedSarr, Awahttps://hdl.handle.net/10023/185032021-04-08T14:16:18Z2019-06-28T00:00:00Z2019-06-28T00:00:00ZSarr, AwaFertility issues and fear of cancer recurrence in young
women with gynaecological or breast cancerSobota, Aleksandrahttps://hdl.handle.net/10023/182052024-01-23T03:06:01Z2016-11-30T00:00:00ZFertility and cancer recurrence fears have been identified as important issues among
young cancer patients (1-3), which frequently remain unaddressed (4, 5). This thesis
aims to investigate the role that these issues play in the lives of young women diagnosed
with breast or gynaecological cancer.
This project consisted of three components – a systematic review of literature, a
qualitative, and a quantitative study. The literature review included both the quantitative
and qualitative evidence and sought to a) identify factors associated with fertility issues;
b) characterise the relationship between fertility issues and psychological well-being;
and c) explore decision-making about treatments that can affect fertility potential among
women diagnosed with cancer during their reproductive years. It used narrative and
thematic synthesis as methods of analysis, and provided the rationale for the qualitative
and quantitative components of this PhD project. In the qualitative study, twenty-four
young women who had finished active cancer treatment were interviewed over the
phone about the importance of their fertility at the time of treatment decision-making. In
the quantitative study, 164 women completed a survey investigating the determinants of
the psychological experience of fertility issues, cancer recurrence fears, and QoL. The
Common Sense and the Shared Decision Making Models have been used to frame and
analyse the data collected throughout the qualitative and quantitative studies..
The literature review suggests that there is a paucity of evidence with respect to the
factors associated with psychological experience of fertility issues among young women
with cancer. It indicates, however, that fertility issues can have a profound impact on
young women’s post-cancer lives in terms of their QoL and ability to regain normality
after cancer treatment. Finally, it provides evidence in favour of the shared decision making
being women’s preferred strategy in terms of making choices about treatments that can affect their fertility potential. These findings, and the gaps identified within the literature are addressed by either the qualitative or the quantitative component of this PhD project.
The qualitative findings suggest that prior to treatments women engaged in a process of
balancing survival and fertility which serves to clarify their priorities with respect to the
treatment outcome. When making treatment decisions, women wished: a) to involve their physicians and their significant others, b) to be informed about treatments, and c) for their priorities to be taken into account as much as possible in the process. This is in line with the basic premises of the Shared Decision Making Model. Determinants of the psychological experience of fertility issues, recurrence fears, and
QoL have been identified throughout the quantitative study. While some of these
determinants differed depending on the psychological outcome, illness perceptions
significantly predicted all of them. This supports the assumptions of the CSM which
suggests that one’s own conceptualisation of disease plays a key role in adapting to an
illness. The findings of this thesis provide insight into the importance of fertility issues and
recurrence fears among young women with breast or gynaecological cancer. The use of
theories enables the design of potential future interventions to improve the patients’ well-being in survivorship.
2016-11-30T00:00:00ZSobota, AleksandraFertility and cancer recurrence fears have been identified as important issues among
young cancer patients (1-3), which frequently remain unaddressed (4, 5). This thesis
aims to investigate the role that these issues play in the lives of young women diagnosed
with breast or gynaecological cancer.
This project consisted of three components – a systematic review of literature, a
qualitative, and a quantitative study. The literature review included both the quantitative
and qualitative evidence and sought to a) identify factors associated with fertility issues;
b) characterise the relationship between fertility issues and psychological well-being;
and c) explore decision-making about treatments that can affect fertility potential among
women diagnosed with cancer during their reproductive years. It used narrative and
thematic synthesis as methods of analysis, and provided the rationale for the qualitative
and quantitative components of this PhD project. In the qualitative study, twenty-four
young women who had finished active cancer treatment were interviewed over the
phone about the importance of their fertility at the time of treatment decision-making. In
the quantitative study, 164 women completed a survey investigating the determinants of
the psychological experience of fertility issues, cancer recurrence fears, and QoL. The
Common Sense and the Shared Decision Making Models have been used to frame and
analyse the data collected throughout the qualitative and quantitative studies..
The literature review suggests that there is a paucity of evidence with respect to the
factors associated with psychological experience of fertility issues among young women
with cancer. It indicates, however, that fertility issues can have a profound impact on
young women’s post-cancer lives in terms of their QoL and ability to regain normality
after cancer treatment. Finally, it provides evidence in favour of the shared decision making
being women’s preferred strategy in terms of making choices about treatments that can affect their fertility potential. These findings, and the gaps identified within the literature are addressed by either the qualitative or the quantitative component of this PhD project.
The qualitative findings suggest that prior to treatments women engaged in a process of
balancing survival and fertility which serves to clarify their priorities with respect to the
treatment outcome. When making treatment decisions, women wished: a) to involve their physicians and their significant others, b) to be informed about treatments, and c) for their priorities to be taken into account as much as possible in the process. This is in line with the basic premises of the Shared Decision Making Model. Determinants of the psychological experience of fertility issues, recurrence fears, and
QoL have been identified throughout the quantitative study. While some of these
determinants differed depending on the psychological outcome, illness perceptions
significantly predicted all of them. This supports the assumptions of the CSM which
suggests that one’s own conceptualisation of disease plays a key role in adapting to an
illness. The findings of this thesis provide insight into the importance of fertility issues and
recurrence fears among young women with breast or gynaecological cancer. The use of
theories enables the design of potential future interventions to improve the patients’ well-being in survivorship.“Yer a total freak show” : a longitudinal mixed-methods study of illness perceptions, self-identity and health behaviour in working-age Phase IV cardiac rehabilitation attendees and the role of spousesNutt, Rachel Annehttps://hdl.handle.net/10023/180422021-03-23T16:41:01Z2019-06-28T00:00:00ZBackground:
Phase IV cardiac rehabilitation (CR) improves outcomes and facilitates behaviour change following myocardial infarction. Although one-third of myocardial infarction (MI) patients in Scotland are under 65 years old, research is lacking in this age group.
Aim:
To explore the experiences, illness perceptions (Leventhal) and self-identity (Charmaz) of working age (18-65 year olds) individuals attending Phase IV cardiac rehabilitation, including around initiation and maintenance of lifestyle change and the role of spouses.
Methods:
16 participants (14 male, 2 female) and 12 spouses (10 female, 2 male) completed nearly 23 hours of semi-structured interviews at the start and end of Phase IV cardiac rehabilitation in Fife and Dundee. Participants completed health behaviour and illness perceptions questionnaires at these time points and after 3 months. Data were integrated and analysed using framework analysis.
Results:
The MI conflicted with participants’ self-identity. Fear and perceived consequences led to restrictive and protective control behaviour from both participants and spouses. CR aided participants goal of ‘getting back to normal’ - providing safety, monitoring and knowledge reduced fear, allowing return to pre-MI activities and behaviour, both healthy and unhealthy. Perceived cause, communication from health professionals, social influences all impacted health behaviour outcomes, which were varied. Although there were improvements in health behaviour at end of CR, these were not sustained at 3-month follow-up.
Identity disruption, mood changes and medication side-effects persisted at 3-month follow-up. Psychological and longer-term support was lacking.
Discussion:
Cardiac rehabilitation is a time of transition, with experiences and outcomes varying between individuals. Participants and health professionals desired behaviour may conflict. Further research should explore long-term outcomes and opportunities for intervention and support in this group, as well as female attendance and gender.
Using longitudinal mixed-methods, and theoretical models provides insight into processes over time but require careful data management and analysis.
2019-06-28T00:00:00ZNutt, Rachel AnneBackground:
Phase IV cardiac rehabilitation (CR) improves outcomes and facilitates behaviour change following myocardial infarction. Although one-third of myocardial infarction (MI) patients in Scotland are under 65 years old, research is lacking in this age group.
Aim:
To explore the experiences, illness perceptions (Leventhal) and self-identity (Charmaz) of working age (18-65 year olds) individuals attending Phase IV cardiac rehabilitation, including around initiation and maintenance of lifestyle change and the role of spouses.
Methods:
16 participants (14 male, 2 female) and 12 spouses (10 female, 2 male) completed nearly 23 hours of semi-structured interviews at the start and end of Phase IV cardiac rehabilitation in Fife and Dundee. Participants completed health behaviour and illness perceptions questionnaires at these time points and after 3 months. Data were integrated and analysed using framework analysis.
Results:
The MI conflicted with participants’ self-identity. Fear and perceived consequences led to restrictive and protective control behaviour from both participants and spouses. CR aided participants goal of ‘getting back to normal’ - providing safety, monitoring and knowledge reduced fear, allowing return to pre-MI activities and behaviour, both healthy and unhealthy. Perceived cause, communication from health professionals, social influences all impacted health behaviour outcomes, which were varied. Although there were improvements in health behaviour at end of CR, these were not sustained at 3-month follow-up.
Identity disruption, mood changes and medication side-effects persisted at 3-month follow-up. Psychological and longer-term support was lacking.
Discussion:
Cardiac rehabilitation is a time of transition, with experiences and outcomes varying between individuals. Participants and health professionals desired behaviour may conflict. Further research should explore long-term outcomes and opportunities for intervention and support in this group, as well as female attendance and gender.
Using longitudinal mixed-methods, and theoretical models provides insight into processes over time but require careful data management and analysis.Title redactedSobczak, Amélie Isabelle Sylviehttps://hdl.handle.net/10023/177772021-05-13T11:55:57Z2019-06-28T00:00:00Z2019-06-28T00:00:00ZSobczak, Amélie Isabelle SylvieTitle redactedAggarwal, Sanyahttps://hdl.handle.net/10023/174442021-02-24T14:37:02Z2019-06-28T00:00:00Z2019-06-28T00:00:00ZAggarwal, SanyaWar surgical experience reduces operation times and saves lives: a comprehensive analysis of all trauma sustained in the Afghanistan conflict 2009-2014 prioritises the surgical procedures to improve training and readiness for future armed conflicts, terror attacks, and civilian damage control surgeryMaitland, Laura Mary Rosehttps://hdl.handle.net/10023/171962023-05-30T02:06:26Z2018-01-01T00:00:00ZBackground: Between 2009 and the end of UK combat operations in Helmand, Afghanistan (2014), each consecutive surgical procedure carried out by the multinational, military surgical team at the Medical Treatment Facility, Camp Bastion was collated. Through analysis I aim to develop the template for prioritising surgical procedures to improve surgical training and readiness for future armed conflicts and terror attacks.
Methods: All surgical teams operating in Camp Bastion filled out detailed, handwritten theatre logbooks for each surgical case. I transcribed all 10,891 consecutive surgical cases, and 20,266 surgical procedures, into an electronic format. I provide for the first time the distinct, original and stand-alone surgical database for this thesis: the “Maitland Module”, the largest of its kind.
Results: I present a new analysis and classification of surgery by anatomical region which accounts for the impact of the multiplicity of wounding caused by explosion on surgical workload. I present the first evidenced-based skill set requirement for war, including the most frequently performed humanitarian surgical procedures and their impact on the skill set required of a surgeon in armed conflict. I show that surgical experience predicted shorter operation times for blast trauma. I found that surgical experience of >50 blast trauma cases predicted lower fatality rates. Skill atrophy in surgical competence between conflicts exists, with an associated rise in preventable loss of life at the start of conflict.
Discussion:
I propose that the Complex Attack Surgical Team (CAST) of surgeons, with >50 blast trauma case experience, be on standby in the event of a terrorist attack in the UK to support the currently blast-naive civilian surgeons.
I hope that the template for surgical procedures may lead to standardisation and prioritisation of the skill set requirement for: trauma surgical training; NATO curriculum development; and intelligent, risk-assessed, deployment of surgeons to conflict zones.
2018-01-01T00:00:00ZMaitland, Laura Mary RoseBackground: Between 2009 and the end of UK combat operations in Helmand, Afghanistan (2014), each consecutive surgical procedure carried out by the multinational, military surgical team at the Medical Treatment Facility, Camp Bastion was collated. Through analysis I aim to develop the template for prioritising surgical procedures to improve surgical training and readiness for future armed conflicts and terror attacks.
Methods: All surgical teams operating in Camp Bastion filled out detailed, handwritten theatre logbooks for each surgical case. I transcribed all 10,891 consecutive surgical cases, and 20,266 surgical procedures, into an electronic format. I provide for the first time the distinct, original and stand-alone surgical database for this thesis: the “Maitland Module”, the largest of its kind.
Results: I present a new analysis and classification of surgery by anatomical region which accounts for the impact of the multiplicity of wounding caused by explosion on surgical workload. I present the first evidenced-based skill set requirement for war, including the most frequently performed humanitarian surgical procedures and their impact on the skill set required of a surgeon in armed conflict. I show that surgical experience predicted shorter operation times for blast trauma. I found that surgical experience of >50 blast trauma cases predicted lower fatality rates. Skill atrophy in surgical competence between conflicts exists, with an associated rise in preventable loss of life at the start of conflict.
Discussion:
I propose that the Complex Attack Surgical Team (CAST) of surgeons, with >50 blast trauma case experience, be on standby in the event of a terrorist attack in the UK to support the currently blast-naive civilian surgeons.
I hope that the template for surgical procedures may lead to standardisation and prioritisation of the skill set requirement for: trauma surgical training; NATO curriculum development; and intelligent, risk-assessed, deployment of surgeons to conflict zones.Identification of novel podocyte stress-response mechanisms in vitroHaley, Kathrynhttps://hdl.handle.net/10023/171662019-07-11T10:07:10Z2018-01-01T00:00:00Z2018-01-01T00:00:00ZHaley, KathrynTitle redactedDiaz Vazquez, Rebecahttps://hdl.handle.net/10023/171392022-10-06T14:48:58Z2018-06-29T00:00:00Z2018-06-29T00:00:00ZDiaz Vazquez, RebecaDetecting mycobacterial cell states using photonicsHammond, Robert James Hunterhttps://hdl.handle.net/10023/170072023-03-21T09:42:55Z2016-11-26T00:00:00ZTuberculosis is an ancient disease with evidence of Mycobacterium tuberculosis bacilli being found in mummies from ancient Egypt. There are also contemporary cases of tuberculosis, worldwide, every day. Like a good parasite Mycobacterium tuberculosis can hide within its host undetected for long periods of time. This state of quiescence has numerous names but in this research we will be referring to mycobacterial dormancy.
This study investigates the continuing problem of dormancy and associated antibiotic resistance in Mycobacterium tuberculosis (MTB). We focused on closely related research surrogates of MTB; M. smegmatis, M. fortuitum, M. marinum and M. bovis (BCG). Phenotypic resistance is defined as antibiotic resistance that arises as a function of an organism’s specific phenotype, rather than its genome and the genes it could express. Dormancy in MTB can arise when a culture of in vitro bacteria ages to the stationary phase or becomes otherwise stressed. In vivo the conditions surrounding dormancy are less well understood.
Dormancy is an ill-defined state of being suggested for MTB characterised by a down shift in metabolic function and a resistance to chemotherapy. It has been noted that a similar phenotype is found in MTB cells that are expressing lipid bodies- lipid rich cells.
We aimed to create a device that could differentiate between lipid rich and lipid poor cells rapidly using photonic technology. In so doing we created a rapid cell quantifying device, SLIC, which we have used and evaluated extensively with both mycobacteria and common nosocomial pathogens.
As another approach we attempted to separate lipid rich from lipid poor cells. This was achieved using a novel buoyant density separation methodology in combination with an adapted lipophilic staining regimen. In combination these two techniques allowed us to generate discreet populations of ≥95% purity which we were then able to experiment on individually.
Due to our novel separation methodology we were able to discover that lipid rich cells are much more resistant to the current anti-tuberculosis frontline treatment (≈40x more resistant). We showed that lipid rich cells down regulate certain nucleic acid markers associated with a quiescent cell state. We were also able to discover that lipid rich cells occur in young unstressed cultures indicating that the accumulation of lipid bodies is a natural part of the mycobacterial cell cycle. This hints at a possible reason for relapse in non-immunocompromised patients that maintain their drug regimen over the entire term.
Given what we have achieved over the course of this work I believe that we are closer to understanding the effects of mycobacterial dormancy on the Mycobacterium tuberculosis bacilli in vivo. Combining this with the invention of SLIC and its capacity to rapidly detect bacteria at unprecedentedly low concentrations we are closer to being able to diagnose and treat patients faster and with less wasted antibiotics than was previously possible.
2016-11-26T00:00:00ZHammond, Robert James HunterTuberculosis is an ancient disease with evidence of Mycobacterium tuberculosis bacilli being found in mummies from ancient Egypt. There are also contemporary cases of tuberculosis, worldwide, every day. Like a good parasite Mycobacterium tuberculosis can hide within its host undetected for long periods of time. This state of quiescence has numerous names but in this research we will be referring to mycobacterial dormancy.
This study investigates the continuing problem of dormancy and associated antibiotic resistance in Mycobacterium tuberculosis (MTB). We focused on closely related research surrogates of MTB; M. smegmatis, M. fortuitum, M. marinum and M. bovis (BCG). Phenotypic resistance is defined as antibiotic resistance that arises as a function of an organism’s specific phenotype, rather than its genome and the genes it could express. Dormancy in MTB can arise when a culture of in vitro bacteria ages to the stationary phase or becomes otherwise stressed. In vivo the conditions surrounding dormancy are less well understood.
Dormancy is an ill-defined state of being suggested for MTB characterised by a down shift in metabolic function and a resistance to chemotherapy. It has been noted that a similar phenotype is found in MTB cells that are expressing lipid bodies- lipid rich cells.
We aimed to create a device that could differentiate between lipid rich and lipid poor cells rapidly using photonic technology. In so doing we created a rapid cell quantifying device, SLIC, which we have used and evaluated extensively with both mycobacteria and common nosocomial pathogens.
As another approach we attempted to separate lipid rich from lipid poor cells. This was achieved using a novel buoyant density separation methodology in combination with an adapted lipophilic staining regimen. In combination these two techniques allowed us to generate discreet populations of ≥95% purity which we were then able to experiment on individually.
Due to our novel separation methodology we were able to discover that lipid rich cells are much more resistant to the current anti-tuberculosis frontline treatment (≈40x more resistant). We showed that lipid rich cells down regulate certain nucleic acid markers associated with a quiescent cell state. We were also able to discover that lipid rich cells occur in young unstressed cultures indicating that the accumulation of lipid bodies is a natural part of the mycobacterial cell cycle. This hints at a possible reason for relapse in non-immunocompromised patients that maintain their drug regimen over the entire term.
Given what we have achieved over the course of this work I believe that we are closer to understanding the effects of mycobacterial dormancy on the Mycobacterium tuberculosis bacilli in vivo. Combining this with the invention of SLIC and its capacity to rapidly detect bacteria at unprecedentedly low concentrations we are closer to being able to diagnose and treat patients faster and with less wasted antibiotics than was previously possible.Gene knock-in as a tool to phenotype clinically relevant varient alleles for studies on malaria pathobiology: proof of concept using the plasmodium knowlesi normocyte binding protein Xa geneMillar, Scott B.https://hdl.handle.net/10023/167512021-06-17T02:07:35Z2017-11-01T00:00:00ZThe zoonotic parasite, Plasmodium knowlesi, is one of five human malaria species. P.
knowlesi is geographically restricted to locations of the long-tailed and pig-tailed
macaque, indigenous across South-East Asia (SEA). Initial research showed that P.
knowlesi was present in the human population in Malaysian Borneo, with subsequent
studies confirming P. knowlesi throughout SEA. P. knowlesi cases were shown to be
both severe (10%) and lethal (2%), with hyperparasitaemia correlating with severe
malaria. Recent work has identified a polymorphism in the essential P. knowlesi
normocyte binding protein Xa (Pknbpxa) gene that associates with high parasitaemia.
The aims of this study were firstly to enhance and standardise the isolation of parasite
DNA from a Biobank of frozen clinical isolates. Alongside this we aimed to take P.
knowlesi whole genome sequence data and identify further mutations in the Pknbpxa
gene linked to severe disease and express these in an in vitro P. knowlesi experimental
line.
Detailed here is the optimisation of the Whatman-Plasmodipur method to purify P.
knowlesi DNA from a Biobank of frozen clinical samples. This resulted in 13/22
samples returning greater than 70% P. knowlesi DNA and within this, 8 samples were
suitable for genome sequencing. Genome sequence data representing cluster type 2 was
used to inform the synthesis and construction of a Pknbpxa synthetic gene representing
clinical alleles. Single-crossover homologous recombination was used to replace the
native Pknbpxa with this synthetic copy, containing polymorphisms associated with
high parasitaemia. This was subsequently transfected into the P. knowlesi A.1-H.1 clone
via nucleofection, resulting in an experimental line expressing clinically relevant
mutations within the essential PkNBPXa invasion gene. The construction of this
translational approach enables functional examination for mutation involvement in
parasite erythrocyte invasion and contribution to severe disease.
2017-11-01T00:00:00ZMillar, Scott B.The zoonotic parasite, Plasmodium knowlesi, is one of five human malaria species. P.
knowlesi is geographically restricted to locations of the long-tailed and pig-tailed
macaque, indigenous across South-East Asia (SEA). Initial research showed that P.
knowlesi was present in the human population in Malaysian Borneo, with subsequent
studies confirming P. knowlesi throughout SEA. P. knowlesi cases were shown to be
both severe (10%) and lethal (2%), with hyperparasitaemia correlating with severe
malaria. Recent work has identified a polymorphism in the essential P. knowlesi
normocyte binding protein Xa (Pknbpxa) gene that associates with high parasitaemia.
The aims of this study were firstly to enhance and standardise the isolation of parasite
DNA from a Biobank of frozen clinical isolates. Alongside this we aimed to take P.
knowlesi whole genome sequence data and identify further mutations in the Pknbpxa
gene linked to severe disease and express these in an in vitro P. knowlesi experimental
line.
Detailed here is the optimisation of the Whatman-Plasmodipur method to purify P.
knowlesi DNA from a Biobank of frozen clinical samples. This resulted in 13/22
samples returning greater than 70% P. knowlesi DNA and within this, 8 samples were
suitable for genome sequencing. Genome sequence data representing cluster type 2 was
used to inform the synthesis and construction of a Pknbpxa synthetic gene representing
clinical alleles. Single-crossover homologous recombination was used to replace the
native Pknbpxa with this synthetic copy, containing polymorphisms associated with
high parasitaemia. This was subsequently transfected into the P. knowlesi A.1-H.1 clone
via nucleofection, resulting in an experimental line expressing clinically relevant
mutations within the essential PkNBPXa invasion gene. The construction of this
translational approach enables functional examination for mutation involvement in
parasite erythrocyte invasion and contribution to severe disease.Title redactedKennedy, John Allanhttps://hdl.handle.net/10023/166252019-08-16T11:17:18Z2017-06-23T00:00:00Z2017-06-23T00:00:00ZKennedy, John AllanUsing human iPSC-derived neural progenitor cells to increase integrin expression in the CNSForbes, Lindsey H.https://hdl.handle.net/10023/165672022-10-14T09:50:12Z2018-01-16T00:00:00ZRepair of the adult mammalian spinal cord is prohibited by several extrinsic and intrinsic factors. As the CNS matures, growth-promoting proteins such as integrins are developmentally downregulated resulting in a reduced capacity for axonal outgrowth. Integrins are heterodimeric receptors involved in cell-cell and cell-matrix interactions. Specifically, within mature corticospinal tract (CST) axons, integrins are not transported into the axonal compartment. One integrin heterodimer, α9β1, is of particular interest for its ability to promote neurite outgrowth when bound to a component of the injury-induced milieu, tenascin-C. This project aimed to increase integrin expression within the CNS using induced pluripotent stem cell-derived human neural progenitor cells (iPSC-hNPCs).
Using immunocytochemistry and western blotting, endogenous integrin expression within iPSC-hNPCs was determined. In addition, overexpression of α9 integrin was achieved using transfection and lentiviral transduction. The capacity of wild type (WT) and α9-hNPCs to extend neurites on tenascin-C was assessed using neurite outgrowth assays. Results revealed increasing α9 integrin expression in hNPCs significantly promoted neurite outgrowth when cultured on tenascin-C. Interestingly, increasing the concentration of human tenascin-C, resulted in increasingly longer neurites from WT hNPCs suggesting hNPCs could actively upregulate integrin expression. Subsequently, WT and α9-hNPCs were transplanted into layer V of the neonatal rat sensorimotor cortex, which projects to the CST. WT and α9-hNPCs survived up to 8 weeks post-transplantation and produced projections along white matter tracts, including areas of the CST. Additionally, hNPCs retained α9-eYFP protein expression in vivo over time and was localised within axonal projections.
These results highlight the capabilities of iPSC-hNPCs to promote integrin expression within the rodent CNS presenting one potential avenue to target neuronal replacement following spinal injury. Future research should focus on assessing the regenerative capacity of WT and α9-hNPCs within an injury model concentrating on the ability of these cells to adapt within an injured environment.
2018-01-16T00:00:00ZForbes, Lindsey H.Repair of the adult mammalian spinal cord is prohibited by several extrinsic and intrinsic factors. As the CNS matures, growth-promoting proteins such as integrins are developmentally downregulated resulting in a reduced capacity for axonal outgrowth. Integrins are heterodimeric receptors involved in cell-cell and cell-matrix interactions. Specifically, within mature corticospinal tract (CST) axons, integrins are not transported into the axonal compartment. One integrin heterodimer, α9β1, is of particular interest for its ability to promote neurite outgrowth when bound to a component of the injury-induced milieu, tenascin-C. This project aimed to increase integrin expression within the CNS using induced pluripotent stem cell-derived human neural progenitor cells (iPSC-hNPCs).
Using immunocytochemistry and western blotting, endogenous integrin expression within iPSC-hNPCs was determined. In addition, overexpression of α9 integrin was achieved using transfection and lentiviral transduction. The capacity of wild type (WT) and α9-hNPCs to extend neurites on tenascin-C was assessed using neurite outgrowth assays. Results revealed increasing α9 integrin expression in hNPCs significantly promoted neurite outgrowth when cultured on tenascin-C. Interestingly, increasing the concentration of human tenascin-C, resulted in increasingly longer neurites from WT hNPCs suggesting hNPCs could actively upregulate integrin expression. Subsequently, WT and α9-hNPCs were transplanted into layer V of the neonatal rat sensorimotor cortex, which projects to the CST. WT and α9-hNPCs survived up to 8 weeks post-transplantation and produced projections along white matter tracts, including areas of the CST. Additionally, hNPCs retained α9-eYFP protein expression in vivo over time and was localised within axonal projections.
These results highlight the capabilities of iPSC-hNPCs to promote integrin expression within the rodent CNS presenting one potential avenue to target neuronal replacement following spinal injury. Future research should focus on assessing the regenerative capacity of WT and α9-hNPCs within an injury model concentrating on the ability of these cells to adapt within an injured environment.Phenotypic discrimination of Mycobacterium tuberculosis by Raman spectroscopyBaron, Vincenthttps://hdl.handle.net/10023/165622019-07-12T11:49:41Z2018-06-29T00:00:00ZTB remains a major health issue worldwide causing around 1.5 deaths each year. The recent phase III clinical trials of shortened TB treatment failed to show superiority compared to the current regimen and this mainly because of relapse. Relapse is thought to be caused by dormant bacteria. Dormancy in Mycobacterium species has been shown to be associated with the accumulation of intracellular lipids, defining two phenotypes: the lipid rich (LR) cells (associated with dormancy) and the lipid poor (LP) cells (non-dormant). LR cells were shown to have a higher phenotypic antibiotic resistance compared to LP cells. Studying these two phenotypes is therefore central in tuberculosis research to understand better the disease and also potentially start to reveal the bacteriology of relapse.
We investigated the power of Raman spectroscopy, a label-free and non-destructive technique, to discriminate LR and LP bacteria both in-vitro and ex-vivo. This represents the first Raman spectroscopy study that tries to discriminate the phenotypes of M. tuberculosis and investigate them directly at the site of the disease.
Using total lipid extract of M. tuberculosis, we showed the location of the main lipid bands in the Raman spectrum. The two major lipid peaks were located around 1300 cm⁻¹ and 1450 cm⁻¹.
Raman spectroscopy can discriminate LR and LP cells with high sensitivity and specificity. The main differences between the two groups are located in the two major Raman lipid peaks, the lipid band A (1300 cm⁻¹) and lipid band B (1440 to 1450 cm⁻¹). The two phenotypes were successfully discriminated in TB infected guinea pig lung tissue sections also from in-vitro culture using wavelength modulated Raman (WMR) spectroscopy combined with fluorescence imaging. We developed a protocol to perform both Raman spectroscopy and immunohistochemistry on the same tissue sample.
We studied the evolution of LR and LP proportion in mycobacterial population as the growth conditions changed and showed that LR cells could rapidly convert to LP cells as they face favourable growth conditions.
The results presented in this thesis showed that LR M. tuberculosis cells could be predominant at the site of infection. This would suggest that drug sensitivity testing should be performed on culture presenting both LR and LP cells in high proportion.
2018-06-29T00:00:00ZBaron, VincentTB remains a major health issue worldwide causing around 1.5 deaths each year. The recent phase III clinical trials of shortened TB treatment failed to show superiority compared to the current regimen and this mainly because of relapse. Relapse is thought to be caused by dormant bacteria. Dormancy in Mycobacterium species has been shown to be associated with the accumulation of intracellular lipids, defining two phenotypes: the lipid rich (LR) cells (associated with dormancy) and the lipid poor (LP) cells (non-dormant). LR cells were shown to have a higher phenotypic antibiotic resistance compared to LP cells. Studying these two phenotypes is therefore central in tuberculosis research to understand better the disease and also potentially start to reveal the bacteriology of relapse.
We investigated the power of Raman spectroscopy, a label-free and non-destructive technique, to discriminate LR and LP bacteria both in-vitro and ex-vivo. This represents the first Raman spectroscopy study that tries to discriminate the phenotypes of M. tuberculosis and investigate them directly at the site of the disease.
Using total lipid extract of M. tuberculosis, we showed the location of the main lipid bands in the Raman spectrum. The two major lipid peaks were located around 1300 cm⁻¹ and 1450 cm⁻¹.
Raman spectroscopy can discriminate LR and LP cells with high sensitivity and specificity. The main differences between the two groups are located in the two major Raman lipid peaks, the lipid band A (1300 cm⁻¹) and lipid band B (1440 to 1450 cm⁻¹). The two phenotypes were successfully discriminated in TB infected guinea pig lung tissue sections also from in-vitro culture using wavelength modulated Raman (WMR) spectroscopy combined with fluorescence imaging. We developed a protocol to perform both Raman spectroscopy and immunohistochemistry on the same tissue sample.
We studied the evolution of LR and LP proportion in mycobacterial population as the growth conditions changed and showed that LR cells could rapidly convert to LP cells as they face favourable growth conditions.
The results presented in this thesis showed that LR M. tuberculosis cells could be predominant at the site of infection. This would suggest that drug sensitivity testing should be performed on culture presenting both LR and LP cells in high proportion.Towards light sheet microscopy-based high
throughput imaging and CRISPR optogeneticsGasparoli, Federico Mariahttps://hdl.handle.net/10023/164482023-07-28T14:54:48Z2018-12-06T00:00:00ZHigh Throughput Imaging (HTI) has an important role in the High Throughput/Content
Screening process (HTS/HCS). It is widely used in the drug discovery process and in a
wide range of other applications including studies focused on cell cycle, cell
proliferation, cell migration, apoptosis, protein expression, protein localization,
signalling pathways or stem cell development and differentiation. Nowadays, most of
the HCS experiments are performed on two-dimensional (2D) monolayer of cells
cultured on planar plastic substrates which do not reflect the complex 3D architecture
of a living tissues where the cells interact between each other and with the ExtraCellular
Matrix (ECM). Currently, the state-of-the-art HCS systems that can be used for high
throughput imaging of 3D cell culture models are based on confocal microscopy. Even
though very efficient, these machines can reach the million-dollar price and thus might
be affordable to big industry and phenotypic screening centres but not to most of
smaller realities such as academic laboratories. This thesis project proposes a solution
to link light sheet microscopy, one of the best techniques for the imaging of 3D cell
culture models, with the currently available HTS/HCS platforms: the development of the
affordable and user-friendly HT-LISH microscope first prototype have the potential to
offer automated light sheet microscopy-based HTI capabilities for the study of 3D
samples to industries, screening centres and also to smaller laboratories, where a lower
throughput level is eventually required.
Another important part of this PhD thesis is focused on CRISPR-based genome editing
which during the recent decades has become an invaluable tool in cell and tissue
biology. CRISPR interference (CRISPRi) and activation (CRISPRa) systems have been
developed to allow the users to up-or down-regulate any gene of interest in a relative
simple manner. Even though emerged as powerful techniques to regulate the gene
expression levels, these tools lack in spatiotemporal resolution. In order to study and
understand genetic patterns specific to a certain type of tissue it is important to achieve
a precise control over the CRISPRi/a systems so that they can be selectively targeted to
small populations of cells (spatial resolution) or be activated and de-activated at will
(temporal resolution). This work, describes the development and the characterization of the Red Light CRISPR system, a novel CRISPR-based tool for precise gene regulation
experiments that relies on the interaction of the Phytochrome B (PhyB) and
Phytochrome-Interacting Factor 6 (PIF6), two light sensitive protein from the plant
Arabidopsis Thaliana that dimerize under red light at 660 nm and separate when
illuminated with infrared light at 740 nm. The Red Light CRISPR system fuses together
the non-invasive and highly spatiotemporal resolved technique of optogenetics with the
“easy to use” and efficient CRISPR approach. This system is thus joining the already
available range of optogenetics tools that enable a precise spatiotemporal control of the
CRISPR system and, in particular, it introduces for the first time a red/infrared lightbased
CRISPR inducible system.
2018-12-06T00:00:00ZGasparoli, Federico MariaHigh Throughput Imaging (HTI) has an important role in the High Throughput/Content
Screening process (HTS/HCS). It is widely used in the drug discovery process and in a
wide range of other applications including studies focused on cell cycle, cell
proliferation, cell migration, apoptosis, protein expression, protein localization,
signalling pathways or stem cell development and differentiation. Nowadays, most of
the HCS experiments are performed on two-dimensional (2D) monolayer of cells
cultured on planar plastic substrates which do not reflect the complex 3D architecture
of a living tissues where the cells interact between each other and with the ExtraCellular
Matrix (ECM). Currently, the state-of-the-art HCS systems that can be used for high
throughput imaging of 3D cell culture models are based on confocal microscopy. Even
though very efficient, these machines can reach the million-dollar price and thus might
be affordable to big industry and phenotypic screening centres but not to most of
smaller realities such as academic laboratories. This thesis project proposes a solution
to link light sheet microscopy, one of the best techniques for the imaging of 3D cell
culture models, with the currently available HTS/HCS platforms: the development of the
affordable and user-friendly HT-LISH microscope first prototype have the potential to
offer automated light sheet microscopy-based HTI capabilities for the study of 3D
samples to industries, screening centres and also to smaller laboratories, where a lower
throughput level is eventually required.
Another important part of this PhD thesis is focused on CRISPR-based genome editing
which during the recent decades has become an invaluable tool in cell and tissue
biology. CRISPR interference (CRISPRi) and activation (CRISPRa) systems have been
developed to allow the users to up-or down-regulate any gene of interest in a relative
simple manner. Even though emerged as powerful techniques to regulate the gene
expression levels, these tools lack in spatiotemporal resolution. In order to study and
understand genetic patterns specific to a certain type of tissue it is important to achieve
a precise control over the CRISPRi/a systems so that they can be selectively targeted to
small populations of cells (spatial resolution) or be activated and de-activated at will
(temporal resolution). This work, describes the development and the characterization of the Red Light CRISPR system, a novel CRISPR-based tool for precise gene regulation
experiments that relies on the interaction of the Phytochrome B (PhyB) and
Phytochrome-Interacting Factor 6 (PIF6), two light sensitive protein from the plant
Arabidopsis Thaliana that dimerize under red light at 660 nm and separate when
illuminated with infrared light at 740 nm. The Red Light CRISPR system fuses together
the non-invasive and highly spatiotemporal resolved technique of optogenetics with the
“easy to use” and efficient CRISPR approach. This system is thus joining the already
available range of optogenetics tools that enable a precise spatiotemporal control of the
CRISPR system and, in particular, it introduces for the first time a red/infrared lightbased
CRISPR inducible system.Zebrafish as a model to study genes associated with neurodevelopmental disordersGostić, Monikahttps://hdl.handle.net/10023/164462023-05-29T14:34:32Z2018-12-06T00:00:00ZDyslexia is a neurodevelopmental disorder that affects between 5% and 12% of school-aged children. Individuals with dyslexia have difficulties in learning to read despite normal IQ levels and adequate socio-economical and educational opportunities. Dyslexia has a strong genetic component, but only a few candidate genes have been characterized to date. The KIAA0319 gene is a strong dyslexia candidate found to be associated with dyslexia in independent studies. The KIAA0319 genetic variants associated with dyslexia reside in a regulatory region. Studies in rat suggested that this gene is required for neuronal migration during early cortex formation. The KIAA0319-like (KIAA0319L) is a KIAA0319 homolog in structure and has recently been shown to play a role in dyslexia. I used zebrafish as a model organism both to study the effects of non-coding variants and to characterise kiaa0319 gene function. I used Gateway Tol2 technology to study the role of regulatory sequences. While these experiments led to inconclusive results, they highlighted some of the challenges but also the feasibility of using zebrafish as model organism to study genetic associations. In parallel, I studied the kiaa0319 function with knockout and knockdown experiments. Additionally, I conducted a detailed gene expression analysis with different in situ hybridisation protocols showing kiaa0319 ubiquitous expression in the whole embryo before 12 hours post fertilisation, with later specification to the eyes, brain, otic vesicle and notochord. Additionally, I have tested for the expression of kiaa0319l and showed similar expression pattern to the kiaa0319, but with significantly lower expression of kiaa0319l in zebrafish notochord. My data show, for the first time, that kiaa0319 has stage-specific expression in the brain and notochord during zebrafish early development, suggesting kiaa0319 specific role in the development of these structures. These results are in line with recent mouse studies. With this project I support the idea of kiaa0319 role being extended beyond the brain function and propose a role for kiaa03019 in the visual system and in the notochord.
2018-12-06T00:00:00ZGostić, MonikaDyslexia is a neurodevelopmental disorder that affects between 5% and 12% of school-aged children. Individuals with dyslexia have difficulties in learning to read despite normal IQ levels and adequate socio-economical and educational opportunities. Dyslexia has a strong genetic component, but only a few candidate genes have been characterized to date. The KIAA0319 gene is a strong dyslexia candidate found to be associated with dyslexia in independent studies. The KIAA0319 genetic variants associated with dyslexia reside in a regulatory region. Studies in rat suggested that this gene is required for neuronal migration during early cortex formation. The KIAA0319-like (KIAA0319L) is a KIAA0319 homolog in structure and has recently been shown to play a role in dyslexia. I used zebrafish as a model organism both to study the effects of non-coding variants and to characterise kiaa0319 gene function. I used Gateway Tol2 technology to study the role of regulatory sequences. While these experiments led to inconclusive results, they highlighted some of the challenges but also the feasibility of using zebrafish as model organism to study genetic associations. In parallel, I studied the kiaa0319 function with knockout and knockdown experiments. Additionally, I conducted a detailed gene expression analysis with different in situ hybridisation protocols showing kiaa0319 ubiquitous expression in the whole embryo before 12 hours post fertilisation, with later specification to the eyes, brain, otic vesicle and notochord. Additionally, I have tested for the expression of kiaa0319l and showed similar expression pattern to the kiaa0319, but with significantly lower expression of kiaa0319l in zebrafish notochord. My data show, for the first time, that kiaa0319 has stage-specific expression in the brain and notochord during zebrafish early development, suggesting kiaa0319 specific role in the development of these structures. These results are in line with recent mouse studies. With this project I support the idea of kiaa0319 role being extended beyond the brain function and propose a role for kiaa03019 in the visual system and in the notochord.Investigating the role of Zn²⁺ in regulating the function of intracellular Ca²⁺-release channelsReilly-O'Donnell, Benedicthttps://hdl.handle.net/10023/161452023-11-30T13:09:33Z2018-12-06T00:00:00ZThe tightly regulated openings of the cardiac ryanodine receptor (RyR2) help to ensure
that intracellular Ca²⁺- release from the sarcoplasmic reticulum (SR) can only occur when
heart contractions are required. Usually this process is self-regulatory, where Ca²⁺ both
activates and inhibits release of further Ca²⁺ from the SR. In the progression of heart
failure some of this control is lost and in rest periods Ca²⁺ can leak from the SR into the
cytosol. Recent evidence has suggested that Zn²⁺- dyshomeostasis may contribute to SR
Ca²⁺- leak but the underlying mechanism is unclear.
Using single channel electrophysiological studies in combination with live cell imaging of
HEK 293 and fibroblasts, this study reveals that Zn²⁺, along with Ca²⁺ and the inhibitor
Mg²⁺, plays a physiological role in the grading of Ca²⁺- release via RyR2. Importantly the
data reveal that pathophysiological concentrations of Zn²⁺ (> 100pM) within the cytosol
remove the requirement of Ca²⁺ to activate RyR2, resulting in irregular channel activity
even in the presence of Mg²⁺. This increase in channel open probability due to Zn²⁺ is
known to be associated with increased Ca²⁺- release events such as Ca²⁺ sparks
suggesting that Zn²⁺ is a regulator of the SR Ca²⁺-leak current.
A potential source of releasable Zn²⁺, which could modulate RyR2 activity in
cardiomyocytes, are the acidic organelles (endosomes and lysosomes). This study
provides key evidence that the two pore channels (TPCs), which are expressed on the
surface of these organelles, are candidate channels for ligand-gated release of Zn²⁺.
Importantly this research demonstrates that dysregulated Zn²⁺ homeostasis, resulting in
elevated Zn²⁺ within the lysosome, has severe consequences upon cellular Ca²⁺- release
from fibroblasts, which is primarily the result of Zn²⁺ acting as a pore blocker of TPC2.
Together these data reveal a key role of Zn²⁺ as a second messenger which can regulate
intracellular Ca²⁺- release in both health and disease.
2018-12-06T00:00:00ZReilly-O'Donnell, BenedictThe tightly regulated openings of the cardiac ryanodine receptor (RyR2) help to ensure
that intracellular Ca²⁺- release from the sarcoplasmic reticulum (SR) can only occur when
heart contractions are required. Usually this process is self-regulatory, where Ca²⁺ both
activates and inhibits release of further Ca²⁺ from the SR. In the progression of heart
failure some of this control is lost and in rest periods Ca²⁺ can leak from the SR into the
cytosol. Recent evidence has suggested that Zn²⁺- dyshomeostasis may contribute to SR
Ca²⁺- leak but the underlying mechanism is unclear.
Using single channel electrophysiological studies in combination with live cell imaging of
HEK 293 and fibroblasts, this study reveals that Zn²⁺, along with Ca²⁺ and the inhibitor
Mg²⁺, plays a physiological role in the grading of Ca²⁺- release via RyR2. Importantly the
data reveal that pathophysiological concentrations of Zn²⁺ (> 100pM) within the cytosol
remove the requirement of Ca²⁺ to activate RyR2, resulting in irregular channel activity
even in the presence of Mg²⁺. This increase in channel open probability due to Zn²⁺ is
known to be associated with increased Ca²⁺- release events such as Ca²⁺ sparks
suggesting that Zn²⁺ is a regulator of the SR Ca²⁺-leak current.
A potential source of releasable Zn²⁺, which could modulate RyR2 activity in
cardiomyocytes, are the acidic organelles (endosomes and lysosomes). This study
provides key evidence that the two pore channels (TPCs), which are expressed on the
surface of these organelles, are candidate channels for ligand-gated release of Zn²⁺.
Importantly this research demonstrates that dysregulated Zn²⁺ homeostasis, resulting in
elevated Zn²⁺ within the lysosome, has severe consequences upon cellular Ca²⁺- release
from fibroblasts, which is primarily the result of Zn²⁺ acting as a pore blocker of TPC2.
Together these data reveal a key role of Zn²⁺ as a second messenger which can regulate
intracellular Ca²⁺- release in both health and disease.Transforming clinical mycobacteriology with modern molecular methodologyAlateah, Souad Mohammedhttps://hdl.handle.net/10023/159202020-11-04T14:05:46Z2018-01-01T00:00:00ZWhole genome sequencing (WGS) is an attractive approach for mycobacteria diagnosis and epidemiological studies. It provides the potential for a rapid method that produces detailed information and could theoretically be used as a routine tool in clinical settings. This thesis focuses on the benefits and challenges involved in transforming molecular approaches into practical clinical mycobacteriology in general, and in particular WGS, as well as examining how it might be implemented.
We first set out to improve the quantification of viable mycobacteria cells in vitro and make the molecular bacterial load assay (MBLA) sensitive enough to use in future clinical trials that monitor treatment response. The results showed the assay is rapid and accurate in its detection and count of viable bacteria.
WGS was tested with different types of mycobacteria species to address different epidemiological questions. WGS not only provides a higher resolution result than traditional epidemiological methods but it can rapidly identify an outbreak, thus simplifying the investigation and reducing the cost.
WGS accurately identified the sources of TB recurrence and could therefore have a potential role in determining the endpoints for clinical trials. Rapid genotyping of species in this way has been demonstrated in our studies. In addition, WGS has the ability to, in most circumstances, predict TB drug resistance. This could also prove very beneficial from a clinical standpoint.
We used different approaches in our studies; for example, single nucleotide polymorphism threshold methods and the creation of a putative outbreak reference genome, which can be used in future outbreak investigations.
WGS is a cost-effective, high-resolution method with a short turnaround. This makes it potentially usable as a routine tool in clinical settings and reference laboratories. Future studies are needed to improve the mycobacterial genome sequencing procedure, analysis and bioinformatics in order to implement WGS in clinical practice.
2018-01-01T00:00:00ZAlateah, Souad MohammedWhole genome sequencing (WGS) is an attractive approach for mycobacteria diagnosis and epidemiological studies. It provides the potential for a rapid method that produces detailed information and could theoretically be used as a routine tool in clinical settings. This thesis focuses on the benefits and challenges involved in transforming molecular approaches into practical clinical mycobacteriology in general, and in particular WGS, as well as examining how it might be implemented.
We first set out to improve the quantification of viable mycobacteria cells in vitro and make the molecular bacterial load assay (MBLA) sensitive enough to use in future clinical trials that monitor treatment response. The results showed the assay is rapid and accurate in its detection and count of viable bacteria.
WGS was tested with different types of mycobacteria species to address different epidemiological questions. WGS not only provides a higher resolution result than traditional epidemiological methods but it can rapidly identify an outbreak, thus simplifying the investigation and reducing the cost.
WGS accurately identified the sources of TB recurrence and could therefore have a potential role in determining the endpoints for clinical trials. Rapid genotyping of species in this way has been demonstrated in our studies. In addition, WGS has the ability to, in most circumstances, predict TB drug resistance. This could also prove very beneficial from a clinical standpoint.
We used different approaches in our studies; for example, single nucleotide polymorphism threshold methods and the creation of a putative outbreak reference genome, which can be used in future outbreak investigations.
WGS is a cost-effective, high-resolution method with a short turnaround. This makes it potentially usable as a routine tool in clinical settings and reference laboratories. Future studies are needed to improve the mycobacterial genome sequencing procedure, analysis and bioinformatics in order to implement WGS in clinical practice.Title redactedMcHale, Calum Thomashttps://hdl.handle.net/10023/159182022-09-30T09:32:14Z2018-01-01T00:00:00Z2018-01-01T00:00:00ZMcHale, Calum ThomasA functional characterisation of the PCSK6 locus associated with handednessShore, Roberthttps://hdl.handle.net/10023/157192019-04-01T08:52:54Z2016-06-20T00:00:00ZHumans display a 90% population level bias towards right-handedness, implying the vast majority of people have a left-hemisphere dominant for motor control. Although handedness presents a weak, but very consistent heritability across the literature (estimated to be approximately 25%), to date few genetic loci associated with this complex trait have been identified and replicated in subsequent studies. One such gene which has been found to be associated with handedness and subsequently replicated is PCSK6, most recently through a quantitative GWAS (P < 0.5*10⁻⁸, Brandler et al. (2013)). Interestingly, PCSK6 is known to activate Nodal, a morphogen involved in a highly conserved bilaterian pathway known to regulate left-right body axis determination.
Here I present the first molecular characterisation of a handedness-associated region by conducting a detailed functional analysis of the PCSK6 locus, combining genetic analysis, in silico prediction and molecular assays to investigate how common genetic variants influence handedness-related phenotypes. Specifically, I defined the associated locus to be 12.7 kb in size, spanning a predicted 1.8 kb bidirectional promoter which controls the expression of both an antisense long non-coding RNA (lncRNA), and a novel short PCSK6 isoform. A series of luciferase-expressing constructs were generated to characterise the promoter, identifying a minimal sequence capable of driving transcription in a sense strand direction. I have demonstrated experimentally that one of the top associated markers in previous GWA studies, rs11855145, directly creates/disrupts a suspected transcription factor bind site in the vicinity of this bidirectional promoter.
Further functional studies of the genetic variation within PCSK6 may help explain the molecular regulatory mechanisms affecting gene expression. This project provides a model for assays to study other GWAS-nominated candidate genes, and in particular for establishing the role of noncoding variants. The findings from this study support the role of common variants in influencing complex phenotypes, such as handedness.
2016-06-20T00:00:00ZShore, RobertHumans display a 90% population level bias towards right-handedness, implying the vast majority of people have a left-hemisphere dominant for motor control. Although handedness presents a weak, but very consistent heritability across the literature (estimated to be approximately 25%), to date few genetic loci associated with this complex trait have been identified and replicated in subsequent studies. One such gene which has been found to be associated with handedness and subsequently replicated is PCSK6, most recently through a quantitative GWAS (P < 0.5*10⁻⁸, Brandler et al. (2013)). Interestingly, PCSK6 is known to activate Nodal, a morphogen involved in a highly conserved bilaterian pathway known to regulate left-right body axis determination.
Here I present the first molecular characterisation of a handedness-associated region by conducting a detailed functional analysis of the PCSK6 locus, combining genetic analysis, in silico prediction and molecular assays to investigate how common genetic variants influence handedness-related phenotypes. Specifically, I defined the associated locus to be 12.7 kb in size, spanning a predicted 1.8 kb bidirectional promoter which controls the expression of both an antisense long non-coding RNA (lncRNA), and a novel short PCSK6 isoform. A series of luciferase-expressing constructs were generated to characterise the promoter, identifying a minimal sequence capable of driving transcription in a sense strand direction. I have demonstrated experimentally that one of the top associated markers in previous GWA studies, rs11855145, directly creates/disrupts a suspected transcription factor bind site in the vicinity of this bidirectional promoter.
Further functional studies of the genetic variation within PCSK6 may help explain the molecular regulatory mechanisms affecting gene expression. This project provides a model for assays to study other GWAS-nominated candidate genes, and in particular for establishing the role of noncoding variants. The findings from this study support the role of common variants in influencing complex phenotypes, such as handedness.Characterisation of phospholipase C-η enzymes and their relevance to diseaseArastoo, Mohammedhttps://hdl.handle.net/10023/156982019-04-01T08:53:32Z2016-01-01T00:00:00ZPhospholipase C enzymes are a class of enzymes that catalyse the cleavage of the membrane
phospholipid, phosphatidylinositol bisphosphate (PtdIns(4,5)P₂) into the second messengers,
inositol trisphosphate (Ins(4,5)P₃) and diacylglycerol (DAG). Six classes of PLC enzymes have
been identified based on their structure and mechanism of activation.
PLCηs are the most recently identified family and consist of two isozymes, PLCη1 and PLCη2.
The aim of this thesis is to further understand the mechanisms of PLCη activation, the role of
PLCη2 in relation to neuritogenesis and their roles in certain disease states. Both isoforms were
found to be activated by physiological concentrations of intracellular Ca²⁺. Activation of
PLCη2 by Gß₁γ₂ was confirmed using a bacterial 2A co-expression system to allow expression
of PLCη2, Gß₁ and Gγ₂ with a single plasmid. Localisation studies show a nuclear distribution
for PLCη2, but a cytoplasmic distribution for PLCη1 in a neuroblastoma cells line (Neuro2A).
PLCη2 has been implicated in brain development and neurite formation. Building on this, a
neuronal differentiation model using RA-treated Neuro2A cells stably expressing mutant forms
of PLCη2 was utilised, revealing that PLCη2 activity is essential for neuritogenesis but that
this process is independent of the enzymes high sensitivity towards Ca²⁺. Furthermore, the direct interaction of PLCη2 and LIMK-1, a previously identified PLCη2 associated protein, is confirmed in the aforementioned neuronal model. Due to the high sensitivity of PLCη enzymes to Ca²⁺ and because of their presence within neurons, they may be involved in Ca²⁺ dysregulation that occurs in certain diseases such as Alzheimer’s disease (AD). The role of PLCη2 was assessed in amyloid-ß (Aß) treated
differentiated Neuro2A cells, a cellular model for AD pathogenesis. Also a developmental role for PLCη1 was investigated due to a recently identified PLCη1 polymorphism in patients with holoprosencephaly, an embryonic midline defect.
2016-01-01T00:00:00ZArastoo, MohammedPhospholipase C enzymes are a class of enzymes that catalyse the cleavage of the membrane
phospholipid, phosphatidylinositol bisphosphate (PtdIns(4,5)P₂) into the second messengers,
inositol trisphosphate (Ins(4,5)P₃) and diacylglycerol (DAG). Six classes of PLC enzymes have
been identified based on their structure and mechanism of activation.
PLCηs are the most recently identified family and consist of two isozymes, PLCη1 and PLCη2.
The aim of this thesis is to further understand the mechanisms of PLCη activation, the role of
PLCη2 in relation to neuritogenesis and their roles in certain disease states. Both isoforms were
found to be activated by physiological concentrations of intracellular Ca²⁺. Activation of
PLCη2 by Gß₁γ₂ was confirmed using a bacterial 2A co-expression system to allow expression
of PLCη2, Gß₁ and Gγ₂ with a single plasmid. Localisation studies show a nuclear distribution
for PLCη2, but a cytoplasmic distribution for PLCη1 in a neuroblastoma cells line (Neuro2A).
PLCη2 has been implicated in brain development and neurite formation. Building on this, a
neuronal differentiation model using RA-treated Neuro2A cells stably expressing mutant forms
of PLCη2 was utilised, revealing that PLCη2 activity is essential for neuritogenesis but that
this process is independent of the enzymes high sensitivity towards Ca²⁺. Furthermore, the direct interaction of PLCη2 and LIMK-1, a previously identified PLCη2 associated protein, is confirmed in the aforementioned neuronal model. Due to the high sensitivity of PLCη enzymes to Ca²⁺ and because of their presence within neurons, they may be involved in Ca²⁺ dysregulation that occurs in certain diseases such as Alzheimer’s disease (AD). The role of PLCη2 was assessed in amyloid-ß (Aß) treated
differentiated Neuro2A cells, a cellular model for AD pathogenesis. Also a developmental role for PLCη1 was investigated due to a recently identified PLCη1 polymorphism in patients with holoprosencephaly, an embryonic midline defect.Testing the effectiveness of gain- and loss-framed physical activity messages in relation to stress Management : a cross-cultural studyOzgur Polat, Pelinhttps://hdl.handle.net/10023/142702024-01-22T13:34:27Z2018-06-29T00:00:00ZThe current PhD thesis aimed to cross-culturally investigate the effectiveness of gain- and loss-framed physical activity messages among the university students in Turkey and the UK. This study sought to test the impact of the physical activity messages focusing on stress-related effects on physical activity intentions, attitudes and behaviours of the target group. The messages were developed based on the findings of a series of preliminary studies targeting to determine the characteristics and needs of the target groups, and identify the barriers to engage in physical activity.
Two quasi-experimental studies were conducted with 309 university students from the two countries (200 participants from Turkey and 109 participants from the UK) to test the effects of framed messages on intentions and attitudes towards physical activity, and physical activity behaviour change in two weeks after message exposure.
Results showed that immediate effects of both gain- and loss-framed messages on physical activity intentions and attitudes were significant in Turkey and the UK. However, these effects could not be maintained in the two weeks following the message exposure. Moreover, the loss-framed message led to a message reactance in the UK, and physical activity intensity of the participants in the loss-framed group were significantly decreased compared to their baseline physical activity levels.
The present study was the first message framing study comparing Turkey and the UK in terms of the impact of gain- and loss-framed framed physical activity messages. Therefore, this study contributes to the literature through providing evidence on the effects of message framing interventions which are developed and implemented in different cultures. Recommendations for future message framing research include measuring physical activity behaviour through objective methods, and examining the impact of the tailored messages through using different dissemination methods in larger samples.
2018-06-29T00:00:00ZOzgur Polat, PelinThe current PhD thesis aimed to cross-culturally investigate the effectiveness of gain- and loss-framed physical activity messages among the university students in Turkey and the UK. This study sought to test the impact of the physical activity messages focusing on stress-related effects on physical activity intentions, attitudes and behaviours of the target group. The messages were developed based on the findings of a series of preliminary studies targeting to determine the characteristics and needs of the target groups, and identify the barriers to engage in physical activity.
Two quasi-experimental studies were conducted with 309 university students from the two countries (200 participants from Turkey and 109 participants from the UK) to test the effects of framed messages on intentions and attitudes towards physical activity, and physical activity behaviour change in two weeks after message exposure.
Results showed that immediate effects of both gain- and loss-framed messages on physical activity intentions and attitudes were significant in Turkey and the UK. However, these effects could not be maintained in the two weeks following the message exposure. Moreover, the loss-framed message led to a message reactance in the UK, and physical activity intensity of the participants in the loss-framed group were significantly decreased compared to their baseline physical activity levels.
The present study was the first message framing study comparing Turkey and the UK in terms of the impact of gain- and loss-framed framed physical activity messages. Therefore, this study contributes to the literature through providing evidence on the effects of message framing interventions which are developed and implemented in different cultures. Recommendations for future message framing research include measuring physical activity behaviour through objective methods, and examining the impact of the tailored messages through using different dissemination methods in larger samples.Can exosomes be used as drug delivery vesicles?Cooke, Fiona Ghina Maryhttps://hdl.handle.net/10023/136572019-04-01T08:52:49Z2018-06-29T00:00:00ZThe inflammatory arthritis Ankylosing Spondylitis (AS) is linked to the human leucocyte antigen HLA-B27. HLA-B27 is thought to drive AS because it misfolds during assembly in the endoplasmic reticulum (ER), inducing ER cell stress. Modulating HLA-B27 folding in the ER is therefore a therapeutic target pathway. The recent discovery of polymorphisms in the ER-resident peptidase ERAP1 that can impact on HLA-B27 and AS, makes ERAP1 one such target.
Exosomes are small, typically 50-200 nm sized particles, formed in the endosomal recycling pathway, which can be released into the extracellular environment. Exosomes have a wide range of biological activities depending on the cell type of origin, and on the delivered cargo, which can include bio-active proteins, lipids, mRNA and miRNA. There is interest in the use of exosomes as drug delivery agents. Here, exosomes were studied as a delivery agent to modulate ERAP1, as a potential therapeutic tool for the treatment of AS.
Exosomes, isolated from cell lines including CEM and Jurkat (T cell lineage), Jesthom (B cell lineage), U937 (monocyte lineage) and the epithelial HeLa cell line, were characterized by nanoparticle tracking analysis, flow cytometry and immunoblotting using markers including CD9, CD63, CD81 and TSG101. Differential expression of these markers in the immune cell lines indicated the complexity of defining exosomes.
EVs were then tested using cell penetrating peptides, electroporation, lipid transfection and sonication for their ability to load FITC-siRNA or FITC-antibody as cargo. Significantly, post-loading RNase A or trypsin incubation demonstrated that many techniques do not lead to efficient cargo loading of exosomes. Sonication proved the most effective technique, with up to 30% efficiency. Loading of exosomes with ERAP1-targetted siRNA did not however lead to notable ERAP1 inhibition. The data indicates that external loading of exosomes with cargo remains a significant challenge in developing exosomes as therapeutic tools.
2018-06-29T00:00:00ZCooke, Fiona Ghina MaryThe inflammatory arthritis Ankylosing Spondylitis (AS) is linked to the human leucocyte antigen HLA-B27. HLA-B27 is thought to drive AS because it misfolds during assembly in the endoplasmic reticulum (ER), inducing ER cell stress. Modulating HLA-B27 folding in the ER is therefore a therapeutic target pathway. The recent discovery of polymorphisms in the ER-resident peptidase ERAP1 that can impact on HLA-B27 and AS, makes ERAP1 one such target.
Exosomes are small, typically 50-200 nm sized particles, formed in the endosomal recycling pathway, which can be released into the extracellular environment. Exosomes have a wide range of biological activities depending on the cell type of origin, and on the delivered cargo, which can include bio-active proteins, lipids, mRNA and miRNA. There is interest in the use of exosomes as drug delivery agents. Here, exosomes were studied as a delivery agent to modulate ERAP1, as a potential therapeutic tool for the treatment of AS.
Exosomes, isolated from cell lines including CEM and Jurkat (T cell lineage), Jesthom (B cell lineage), U937 (monocyte lineage) and the epithelial HeLa cell line, were characterized by nanoparticle tracking analysis, flow cytometry and immunoblotting using markers including CD9, CD63, CD81 and TSG101. Differential expression of these markers in the immune cell lines indicated the complexity of defining exosomes.
EVs were then tested using cell penetrating peptides, electroporation, lipid transfection and sonication for their ability to load FITC-siRNA or FITC-antibody as cargo. Significantly, post-loading RNase A or trypsin incubation demonstrated that many techniques do not lead to efficient cargo loading of exosomes. Sonication proved the most effective technique, with up to 30% efficiency. Loading of exosomes with ERAP1-targetted siRNA did not however lead to notable ERAP1 inhibition. The data indicates that external loading of exosomes with cargo remains a significant challenge in developing exosomes as therapeutic tools.Studies in the morphogenesis of cabbage with special reference to the phenomenon of headingNorth, Christopherhttps://hdl.handle.net/10023/135642019-04-01T08:53:38Z1956-03-01T00:00:00ZAbstract Not Provided
1956-03-01T00:00:00ZNorth, ChristopherAbstract Not ProvidedThe use of claims databases in pharmacoeconomics research : the case of diversified prescription services and otitis mediaBooth, Philiphttps://hdl.handle.net/10023/135602019-04-01T08:53:37Z1999-07-01T00:00:00ZAbstract not provided
1999-07-01T00:00:00ZBooth, PhilipAbstract not providedPharmacoeconomics of antimicrobial usage in the secondary care sectorParker, Sharon Elizabethhttps://hdl.handle.net/10023/135582019-04-01T08:52:27Z1998-02-01T00:00:00ZWith the advent of regular antimicrobial usage there has been recognition, worldwide, that they are overused and misused. The worries of inappropriate usage centre on increased antibiotic resistance with consequent loss of efficacy, unnecessary exposure to toxic side effects and latterly, financial waste. The two studies undertaken for this thesis have attempted to demonstrate how the combination of the costs of treatment with clinical and process measures of outcome could be used to avoid resource wastage. The first study was an audit of aminoglycoside utilisation and the general antibiotic management of gram-negative bacteraemia. The aminoglycosides were found to be poorly managed and associated with several opportunity costs. Three readily measurable indicators of adverse outcome of hospital antibiotic therapy associated with marked increases in hospital treatment costs were characterised. These were: Change to an alternative iv drug regimen, Retreatment with antibiotics in hospital, Readmission with infection. Another area of resource wastage was the excessive use of the intravenous route for antibiotic administration. Detailed feedback of these findings to selected clinicians was used in an attempt to heighten awareness to the management problems and associated cost of the aminoglycosides and to persuade prescribers to reduce the overall use of intravenous antibiotics by taking advantage of oral administration. The second study examined the feasability of non-inpatient intravenous (NIPIV) antibiotic care and compared the costs and benefits of this type of programme with traditional, hospital inpatient treatment. The study concluded that NIPIV care is feasible, appropriate criteria for patient selection were developed and provision of a quality service was shown to be practical. The issue of safety was raised; as a result, the notion of 'acceptable risk' deserves exploration in the further development of NIPIV care. Sensitivity analysis was used to explore the bias introduced to the costings in this study by commercial sponsorship.
1998-02-01T00:00:00ZParker, Sharon ElizabethWith the advent of regular antimicrobial usage there has been recognition, worldwide, that they are overused and misused. The worries of inappropriate usage centre on increased antibiotic resistance with consequent loss of efficacy, unnecessary exposure to toxic side effects and latterly, financial waste. The two studies undertaken for this thesis have attempted to demonstrate how the combination of the costs of treatment with clinical and process measures of outcome could be used to avoid resource wastage. The first study was an audit of aminoglycoside utilisation and the general antibiotic management of gram-negative bacteraemia. The aminoglycosides were found to be poorly managed and associated with several opportunity costs. Three readily measurable indicators of adverse outcome of hospital antibiotic therapy associated with marked increases in hospital treatment costs were characterised. These were: Change to an alternative iv drug regimen, Retreatment with antibiotics in hospital, Readmission with infection. Another area of resource wastage was the excessive use of the intravenous route for antibiotic administration. Detailed feedback of these findings to selected clinicians was used in an attempt to heighten awareness to the management problems and associated cost of the aminoglycosides and to persuade prescribers to reduce the overall use of intravenous antibiotics by taking advantage of oral administration. The second study examined the feasability of non-inpatient intravenous (NIPIV) antibiotic care and compared the costs and benefits of this type of programme with traditional, hospital inpatient treatment. The study concluded that NIPIV care is feasible, appropriate criteria for patient selection were developed and provision of a quality service was shown to be practical. The issue of safety was raised; as a result, the notion of 'acceptable risk' deserves exploration in the further development of NIPIV care. Sensitivity analysis was used to explore the bias introduced to the costings in this study by commercial sponsorship.A study of the nitroprusside anion and some of its analoguesReglinski, Johnhttps://hdl.handle.net/10023/135572019-04-01T08:52:32Z1981-10-01T00:00:00ZSodium nitroprusside is a potent vasodilator and is widely used for lowering the blood pressure during major surgery. The physiological response is said to occur due to a nitrosation reaction at the smooth muscle membrane. The use of sodium nitroprusside has been restricted due to its ability' to release toxic cyanide in-vivo and in-vitro, which can cause severe complications during surgery. Chapter one is a study of the aqueous chemistry of sodium nitroprusside with amines and thiols. It is shown that steric factors play an important role and that thiols are more reactive than amines. The information is used to evaluate the chemical changes expected at the smooth muscle membrane and possible mechanisms for biochemical action. If the toxicity of nitroprusside anion cannot be aleviated the information can be used to evaluate the potential of other inorganic complexes as potential hypertensive agents. Chapter two deals with the biochemical and medical problems associated with sodium nitroprusside therapy. The interaction of the complex with human erytthrocytes is explored and the reasons for cyanide release are discussed. The toxicity associated with the complex is shown to be impossible to eradicate completely and short term measures to minimise the effects are given. Chapter three explores the implications of the nitrosyl stretching frequency and how its value could be used to indicate whether a compound would be expected to exhibit nitroprusside-type chemistry. The reactivity of five nitrosylpentacyanometallates with the simple reagents previously discussed in chapter one are investigated to show that the nitrosyl group can be positive, neutral or negative and that this information could be easily acquired from the stretching frequency of the nitrosyl group in the infra-red. A value for the nitrosyl stretching frequency is given, above which a compound would be expected to exhibit nitroprusside-type chemistry. These compounds would be expected to be vasodilators.
1981-10-01T00:00:00ZReglinski, JohnSodium nitroprusside is a potent vasodilator and is widely used for lowering the blood pressure during major surgery. The physiological response is said to occur due to a nitrosation reaction at the smooth muscle membrane. The use of sodium nitroprusside has been restricted due to its ability' to release toxic cyanide in-vivo and in-vitro, which can cause severe complications during surgery. Chapter one is a study of the aqueous chemistry of sodium nitroprusside with amines and thiols. It is shown that steric factors play an important role and that thiols are more reactive than amines. The information is used to evaluate the chemical changes expected at the smooth muscle membrane and possible mechanisms for biochemical action. If the toxicity of nitroprusside anion cannot be aleviated the information can be used to evaluate the potential of other inorganic complexes as potential hypertensive agents. Chapter two deals with the biochemical and medical problems associated with sodium nitroprusside therapy. The interaction of the complex with human erytthrocytes is explored and the reasons for cyanide release are discussed. The toxicity associated with the complex is shown to be impossible to eradicate completely and short term measures to minimise the effects are given. Chapter three explores the implications of the nitrosyl stretching frequency and how its value could be used to indicate whether a compound would be expected to exhibit nitroprusside-type chemistry. The reactivity of five nitrosylpentacyanometallates with the simple reagents previously discussed in chapter one are investigated to show that the nitrosyl group can be positive, neutral or negative and that this information could be easily acquired from the stretching frequency of the nitrosyl group in the infra-red. A value for the nitrosyl stretching frequency is given, above which a compound would be expected to exhibit nitroprusside-type chemistry. These compounds would be expected to be vasodilators.Studies of serum and erythrocyte membrane proteins in cystic fibrosis and Duchenne muscular dystrophyZinzombe, Ignatius Mufukudzwahttps://hdl.handle.net/10023/135382019-04-01T08:53:42Z1981-09-01T00:00:00Z(I) Recent research on Duchenne muscular dystrophy lends support to the notion that the genetic defect may affect the surface membranes of not only muscle cells but other cells particularly erythrocytes. Abnormalities in the content and compositions of fatty acids and phosphorylations of some erythrocyte membrane laroteins have been reported in support of this hypothesis. SDS gel electrophoresis patterns of erythrocyte membrane proteins from Duchenne muscular dystrophy were reported to be normal. In this report, SDS gel electrophoresis of erythrocyte membrane proteins prepared by hypotononic lysis of red blood cells at pH8, were not able to show any differences between samples from Duchenne muscular dystrophy patients and those from normal control subjects. The relative intensities of the protein bands varied from preparation to preparation but did not follow a pattern that could distinguish control samples from test samples. Two dimensional gel electrophoresis of completely denatured erythrocyte membrane proteins resolved over 150 peptides in 9% gels and over 200 peptides in gels above 12%, but no consistent differences were observed between Duchenne muscular dystrophy samples and those from control subjects. (II) Although cystic fibrosis is the most frequent lethal genetic syndrome among caucasian children, there is no known biochemical or structural defect to account for all its pathophysiological phenomena. Previous reports in other laboratories have shown that a cystic fibrosis protein (CFP) could be demonstrated in sera of over 90% of cystic fibrosis homozygotes by isoelectric focusing. The protein was characterised as having a molecular weight of between 3000-10 000 and pi near pH8.4. Our isoelectric focusing results demonstrated the protein, pI8.5, in 40% of the homozygotes, thus supporting the view that the procedure is not a useful diagnostic tool and that the "cystic fibrosis protein" is not a specific marker for the disorder. We extended this investigation by labellings, with 125I, all the serum Proteins that focused between pH8 and pH9 and then running the labelled proteins in some 15% SDS gels. The results we obtained could not distinguish cystic fibrosis samples from normal control ones. Some studies have suggested that a mutant form of alpha-2-macroglobulin could be the primary defect in cystic fibrosis and also in multiple sclerosis. To test for the presence of charge or size mutations, alpha-2-macroglobulin was subjected to extensive investigations by (i) SDS gel electropihoresis of its heat fragments, (ii) two dimensional gel electrophoresis following complete denaturation and (iii) immune- electrofocusing of its native form. Alpha-2-macroglobulin from cystic fibrosis patients could not be distinguished from that obtained from normal control subjects but that from multiple sclerosis patients showed some different patterns. The significance of the abnormality of ?2M from multiple sclerosis patients needs further investigations. Extensive two dimensional gel electrophoresis of whole serum following complete denaturation were performed but the results did not reveal any consistent differences between cystic fibrosis and multiple sclerosis patients and normal control subjects.
1981-09-01T00:00:00ZZinzombe, Ignatius Mufukudzwa(I) Recent research on Duchenne muscular dystrophy lends support to the notion that the genetic defect may affect the surface membranes of not only muscle cells but other cells particularly erythrocytes. Abnormalities in the content and compositions of fatty acids and phosphorylations of some erythrocyte membrane laroteins have been reported in support of this hypothesis. SDS gel electrophoresis patterns of erythrocyte membrane proteins from Duchenne muscular dystrophy were reported to be normal. In this report, SDS gel electrophoresis of erythrocyte membrane proteins prepared by hypotononic lysis of red blood cells at pH8, were not able to show any differences between samples from Duchenne muscular dystrophy patients and those from normal control subjects. The relative intensities of the protein bands varied from preparation to preparation but did not follow a pattern that could distinguish control samples from test samples. Two dimensional gel electrophoresis of completely denatured erythrocyte membrane proteins resolved over 150 peptides in 9% gels and over 200 peptides in gels above 12%, but no consistent differences were observed between Duchenne muscular dystrophy samples and those from control subjects. (II) Although cystic fibrosis is the most frequent lethal genetic syndrome among caucasian children, there is no known biochemical or structural defect to account for all its pathophysiological phenomena. Previous reports in other laboratories have shown that a cystic fibrosis protein (CFP) could be demonstrated in sera of over 90% of cystic fibrosis homozygotes by isoelectric focusing. The protein was characterised as having a molecular weight of between 3000-10 000 and pi near pH8.4. Our isoelectric focusing results demonstrated the protein, pI8.5, in 40% of the homozygotes, thus supporting the view that the procedure is not a useful diagnostic tool and that the "cystic fibrosis protein" is not a specific marker for the disorder. We extended this investigation by labellings, with 125I, all the serum Proteins that focused between pH8 and pH9 and then running the labelled proteins in some 15% SDS gels. The results we obtained could not distinguish cystic fibrosis samples from normal control ones. Some studies have suggested that a mutant form of alpha-2-macroglobulin could be the primary defect in cystic fibrosis and also in multiple sclerosis. To test for the presence of charge or size mutations, alpha-2-macroglobulin was subjected to extensive investigations by (i) SDS gel electropihoresis of its heat fragments, (ii) two dimensional gel electrophoresis following complete denaturation and (iii) immune- electrofocusing of its native form. Alpha-2-macroglobulin from cystic fibrosis patients could not be distinguished from that obtained from normal control subjects but that from multiple sclerosis patients showed some different patterns. The significance of the abnormality of ?2M from multiple sclerosis patients needs further investigations. Extensive two dimensional gel electrophoresis of whole serum following complete denaturation were performed but the results did not reveal any consistent differences between cystic fibrosis and multiple sclerosis patients and normal control subjects.Development of procedures for assessing the effect of stroke rate on physiological variables during ergometer rowingForsyth, J.J.https://hdl.handle.net/10023/135372019-04-01T08:53:22Z1995-07-01T00:00:00ZTo determine the effect of stroke rate on lactate concentration, oxygen consumption and heart rate during ergometer rowing, pilot investigations were necessary to clarify methodological procedures. To examine the validity of using blood taken from the toe for the assessment of plasma lactate concentration, values were compared with those taken from the fingertip and earlobe. Subjects (n=9) exercised at work intensities corresponding to 76.4+/-6.1% and 91.4+/-4.7% of estimated heart rate maximum for 4 minutes. No significant differences (p<0.05) were found between any of the sites at either work intensity. The toe has the advantage that repeated blood samples may be removed without interrupting the rowing action. A test to establish maximum oxygen consumption (VO2max) was developed for the Concept II rowing ergometer and examined for validity and reliability in 31 rowers. Re-test data for VO2max proved reliable (r=0.86), although not all of the criteria for ascertaining whether a VO2max value had been achieved, were satisfied. This was due to differences in response to maximal exercise among individuals. A final respiratory exchange ratio (RER) of 1.10 rather than 1.15 was recommended as a criterion for establishing VO2max for club level rowers. To determine the highest level of work that can be sustained during rowing exercise without an increase in plasma lactate concentration, 30 subjects exercised for 10 minutes at work intensities corresponding to 75%, 85% and 95% VO2max. From the results, it was hypothesised that subjects could work for 7 minutes at 80% VO2max without significant differences occurring in plasma lactate concentration taken in the last minute of exercise of successive tests. These values were confirmed with a further study on 11 subjects. A method of directly measuring mechanical variables from the ergometer was initiated. It was hypothesised that the data collected from this and preceding studies could be used for further investigation into the effect of stroke rate on both physiological and mechanical variables.
1995-07-01T00:00:00ZForsyth, J.J.To determine the effect of stroke rate on lactate concentration, oxygen consumption and heart rate during ergometer rowing, pilot investigations were necessary to clarify methodological procedures. To examine the validity of using blood taken from the toe for the assessment of plasma lactate concentration, values were compared with those taken from the fingertip and earlobe. Subjects (n=9) exercised at work intensities corresponding to 76.4+/-6.1% and 91.4+/-4.7% of estimated heart rate maximum for 4 minutes. No significant differences (p<0.05) were found between any of the sites at either work intensity. The toe has the advantage that repeated blood samples may be removed without interrupting the rowing action. A test to establish maximum oxygen consumption (VO2max) was developed for the Concept II rowing ergometer and examined for validity and reliability in 31 rowers. Re-test data for VO2max proved reliable (r=0.86), although not all of the criteria for ascertaining whether a VO2max value had been achieved, were satisfied. This was due to differences in response to maximal exercise among individuals. A final respiratory exchange ratio (RER) of 1.10 rather than 1.15 was recommended as a criterion for establishing VO2max for club level rowers. To determine the highest level of work that can be sustained during rowing exercise without an increase in plasma lactate concentration, 30 subjects exercised for 10 minutes at work intensities corresponding to 75%, 85% and 95% VO2max. From the results, it was hypothesised that subjects could work for 7 minutes at 80% VO2max without significant differences occurring in plasma lactate concentration taken in the last minute of exercise of successive tests. These values were confirmed with a further study on 11 subjects. A method of directly measuring mechanical variables from the ergometer was initiated. It was hypothesised that the data collected from this and preceding studies could be used for further investigation into the effect of stroke rate on both physiological and mechanical variables.Positive acceleration and the release of antidiuretic hormone in manGarrow, John Stuarthttps://hdl.handle.net/10023/135362019-04-01T08:53:35Z1961-01-01T00:00:00ZAbstract not provided
1961-01-01T00:00:00ZGarrow, John StuartAbstract not providedCoping strategies and causal attributions following myocardial infarction : a longitudinal studyGudmundsdottir, Hafrunhttps://hdl.handle.net/10023/135342019-04-01T08:53:08Z1996-07-01T00:00:00ZCoping strategies and causal attributions have been shown to be related to recovery and adjustment following illness. Certain coping strategies and causal attributions, such as avoidant coping and other blame have been found to be related to higher levels of distress while others, like behavioural self blame and attention coping have been shown to be related to lower distress. There have however, been few longitudinal studies of the process. The study described here examined coping strategies, causal attributions and levels of distress over a period of 1 year in 91 patients following a first myocardial infarction (MI). Coping strategies (measured by the COPE), causal attributions (measured by open ended questions and a check-list) and distress (measured by the HAD a measure of anxiety and depression with minimal somatic symptoms), were measured within 2 weeks of discharge and at 2, 6 and 12 months post MI. The main findings of the study showed that both coping strategies and causal attributions changed over time. Patients were most likely to use attention coping strategies early following the illness onset but more avoidant and religious coping later on. Patients made fewer attributions as time passed and the most commonly reported causal attributions were stress and smoking. Results further revealed that both coping strategies and causal attributions were either concurrently related to and/or predictive of levels of distress. Avoidant coping was related to higher distress at all assessment times. Furthermore, both characterological self blame and other blame were found to be concurrently related to higher distress, with characterological self blame also being predictive of subsequent higher distress. These findings have implications for care and rehabilitation of cardiac patients as they imply that certain causal attributions and coping strategies might be problematic as regards post MI distress. This points towards the importance of examining and if necessary, altering certain causal attributions and coping strategies in order for the patient to gain the best possible recovery.
1996-07-01T00:00:00ZGudmundsdottir, HafrunCoping strategies and causal attributions have been shown to be related to recovery and adjustment following illness. Certain coping strategies and causal attributions, such as avoidant coping and other blame have been found to be related to higher levels of distress while others, like behavioural self blame and attention coping have been shown to be related to lower distress. There have however, been few longitudinal studies of the process. The study described here examined coping strategies, causal attributions and levels of distress over a period of 1 year in 91 patients following a first myocardial infarction (MI). Coping strategies (measured by the COPE), causal attributions (measured by open ended questions and a check-list) and distress (measured by the HAD a measure of anxiety and depression with minimal somatic symptoms), were measured within 2 weeks of discharge and at 2, 6 and 12 months post MI. The main findings of the study showed that both coping strategies and causal attributions changed over time. Patients were most likely to use attention coping strategies early following the illness onset but more avoidant and religious coping later on. Patients made fewer attributions as time passed and the most commonly reported causal attributions were stress and smoking. Results further revealed that both coping strategies and causal attributions were either concurrently related to and/or predictive of levels of distress. Avoidant coping was related to higher distress at all assessment times. Furthermore, both characterological self blame and other blame were found to be concurrently related to higher distress, with characterological self blame also being predictive of subsequent higher distress. These findings have implications for care and rehabilitation of cardiac patients as they imply that certain causal attributions and coping strategies might be problematic as regards post MI distress. This points towards the importance of examining and if necessary, altering certain causal attributions and coping strategies in order for the patient to gain the best possible recovery.Chemotherapeutic responses of marine myeloid leukemiasAbubakar, Aminu Abdussalamhttps://hdl.handle.net/10023/135222019-04-01T08:53:48Z1990-07-01T00:00:00ZThe murine myeloid leukaemias employed in this study were induced in male CBA/H mice following irradiation with sublethal doses of X-ray. The responses of these leukaemic cell lines and normal (murine) bone marrow cells to cytosine arabinoside and mitoxantrone treatment in vitro were monitored. Both clonogenic, and nonclonogenic chemotherapeutic assays such as radioactive precursor uptake, dye-exclusion assay and autoradiography were employed to determine drug-induced cell lethality. In addition, the in vitro proliferative responses of the leukaemic cell lines and normal bone marrow cells to growth factors were determined using a [3H]thymidine uptake assay. Both cytarabine and mitoxantrone were as toxic to normal bone marrow cells as to leukaemic cells from most of the cell lines. Mitoxantrone appears to be more potent than cytarabine against leukaemic cells in vitro. However, it was also more toxic to normal bone marrow cells. Generally, combinations of cytarabine and mitoxantrone resulted in an additive cytotoxic effect. Mitoxantrone appears to have a narrow therapeutic margin when administered to leukaemia bearing mice in vivo. The response of the (SA7) myeloid leukaemic cell line to mitoxantrone was distinctly different from those reported for murine lymphoid leukaemias (P388 and L1210). Doubling the mitoxantrone dose within the therapeutic range was not accompanied by an increase in the number of long-term survivors (cures). Bone marrow cells of cured mice or normal(CBA/H) mice administered low doses of mitoxantrone became less sensitive to subsequent treatment with mitoxantrone in vitro . Doses of mitoxantrone that resulted in loss of protective effect by bone marrow cells of normal mice were toxic to leukaemia bearing mice. Primary and low cell dose transplant myeloid leukaemias were less responsive to growth factors as compared to the high cell dose passages. The SA2 leukaemic cell line grew in vitro without requirement for growth factors. However, no growth was observed in serum-free medium which suggests that serum was providing the stimulus for in vitro proliferation. Leukaemic bone marrow cells from the SA7 high cell dose passage cell line, were normally responsive to growth factors in vitro. However, at relapse following in vivo treatment with mitoxantrone, the leukaemic cells became significantly (P=0.04) growth factor insensitive. Bone marrow cells of normal mice retained growth factor sensitivity following in vivo treatment with mitoxantrone. Furthermore, bone marrow cells of mice cured of leukaemia by mitoxantrone treatment in vivo were responsive to growth factors. Recovery of growth factor responsiveness occurred when the recurrent leukaemic cells were passaged in normal mice. However, no recovery of growth factor sensitivity was observed when recurrent leukaemic cells were passaged in mice that received a single dose of mitoxantrone (0.75mg/Kg) two days previously. Even after passage in normal mice, the recurrent leukaemic cells were in some cases, significantly (P=0.012) resistant to mitoxantrone treatment in vitro. The degree of resistance appears to depend on the dose of mitoxantrone employed in the treatment of the leukaemia. However, passaging the recurrent leukaemia in mitoxantrone pretreated mice did not increase the level of resistance developed by the leukaemic cells. These results suggest that these myeloid leukaemic cell lines may be useful models for preclinical evaluation of chemotherapeutic agents.
1990-07-01T00:00:00ZAbubakar, Aminu AbdussalamThe murine myeloid leukaemias employed in this study were induced in male CBA/H mice following irradiation with sublethal doses of X-ray. The responses of these leukaemic cell lines and normal (murine) bone marrow cells to cytosine arabinoside and mitoxantrone treatment in vitro were monitored. Both clonogenic, and nonclonogenic chemotherapeutic assays such as radioactive precursor uptake, dye-exclusion assay and autoradiography were employed to determine drug-induced cell lethality. In addition, the in vitro proliferative responses of the leukaemic cell lines and normal bone marrow cells to growth factors were determined using a [3H]thymidine uptake assay. Both cytarabine and mitoxantrone were as toxic to normal bone marrow cells as to leukaemic cells from most of the cell lines. Mitoxantrone appears to be more potent than cytarabine against leukaemic cells in vitro. However, it was also more toxic to normal bone marrow cells. Generally, combinations of cytarabine and mitoxantrone resulted in an additive cytotoxic effect. Mitoxantrone appears to have a narrow therapeutic margin when administered to leukaemia bearing mice in vivo. The response of the (SA7) myeloid leukaemic cell line to mitoxantrone was distinctly different from those reported for murine lymphoid leukaemias (P388 and L1210). Doubling the mitoxantrone dose within the therapeutic range was not accompanied by an increase in the number of long-term survivors (cures). Bone marrow cells of cured mice or normal(CBA/H) mice administered low doses of mitoxantrone became less sensitive to subsequent treatment with mitoxantrone in vitro . Doses of mitoxantrone that resulted in loss of protective effect by bone marrow cells of normal mice were toxic to leukaemia bearing mice. Primary and low cell dose transplant myeloid leukaemias were less responsive to growth factors as compared to the high cell dose passages. The SA2 leukaemic cell line grew in vitro without requirement for growth factors. However, no growth was observed in serum-free medium which suggests that serum was providing the stimulus for in vitro proliferation. Leukaemic bone marrow cells from the SA7 high cell dose passage cell line, were normally responsive to growth factors in vitro. However, at relapse following in vivo treatment with mitoxantrone, the leukaemic cells became significantly (P=0.04) growth factor insensitive. Bone marrow cells of normal mice retained growth factor sensitivity following in vivo treatment with mitoxantrone. Furthermore, bone marrow cells of mice cured of leukaemia by mitoxantrone treatment in vivo were responsive to growth factors. Recovery of growth factor responsiveness occurred when the recurrent leukaemic cells were passaged in normal mice. However, no recovery of growth factor sensitivity was observed when recurrent leukaemic cells were passaged in mice that received a single dose of mitoxantrone (0.75mg/Kg) two days previously. Even after passage in normal mice, the recurrent leukaemic cells were in some cases, significantly (P=0.012) resistant to mitoxantrone treatment in vitro. The degree of resistance appears to depend on the dose of mitoxantrone employed in the treatment of the leukaemia. However, passaging the recurrent leukaemia in mitoxantrone pretreated mice did not increase the level of resistance developed by the leukaemic cells. These results suggest that these myeloid leukaemic cell lines may be useful models for preclinical evaluation of chemotherapeutic agents.Cardiac rehabilitation in the acute post-myocardial infarction periodFoulkes, Joanhttps://hdl.handle.net/10023/135212019-04-01T08:53:09Z1995-07-01T00:00:00ZAbstract not provided
1995-07-01T00:00:00ZFoulkes, JoanAbstract not providedHelping people with learning disabilities express anger in socially acceptable ways : the development of a treatment intervention and outcome measuresBlack, Laurahttps://hdl.handle.net/10023/135142019-04-01T08:52:36Z1994-01-01T00:00:00ZThe focus of this thesis was the evaluation of a treatment to help people who have a learning disability to develop socially appropriate ways of expressing anger. The inability to cope with anger has prevented some people from living an ordinary life in the community. A cognitive behavioural treatment to help people to cope with anger was developed by Novaco (1983b). The aim of the present studies was to examine whether a modification of the treatment developed by Novaco could prove beneficial for a population who have a learning disability. A set of criteria for improvement were devised to operationalise improvement in terms of clinically, as well as statistically significant change. In study 1, twelve people who have a learning disability were assessed on one self report measure and four measures completed by staff; at baseline, at the end of each stage of treatment and follow up. The subjects received approximately fifty weeks of treatment. As the follow up scores met the majority of the criteria for improvement, it was inferred that the subjects had benefited from treatment. A number of methodological modifications were suggested. In study 2, five subjects were assessed on four self report and three staff completed assessments. The four stages of treatment (self monitoring, information giving, relaxation training and problem solving) lasted 27-37 weeks. Four of the five subjects benefited from treatment as their follow up scores met the criteria for improvement. The results allowed cautious optimism about the efficacy of cognitive behavioural techniques and the use of self report measures for people who have a learning disability, who are verbal. The value of embedding this focussed treatment within a broader therapeutic framework, to encompass a wider range of emotions and strategies to cope with stress was discussed.
1994-01-01T00:00:00ZBlack, LauraThe focus of this thesis was the evaluation of a treatment to help people who have a learning disability to develop socially appropriate ways of expressing anger. The inability to cope with anger has prevented some people from living an ordinary life in the community. A cognitive behavioural treatment to help people to cope with anger was developed by Novaco (1983b). The aim of the present studies was to examine whether a modification of the treatment developed by Novaco could prove beneficial for a population who have a learning disability. A set of criteria for improvement were devised to operationalise improvement in terms of clinically, as well as statistically significant change. In study 1, twelve people who have a learning disability were assessed on one self report measure and four measures completed by staff; at baseline, at the end of each stage of treatment and follow up. The subjects received approximately fifty weeks of treatment. As the follow up scores met the majority of the criteria for improvement, it was inferred that the subjects had benefited from treatment. A number of methodological modifications were suggested. In study 2, five subjects were assessed on four self report and three staff completed assessments. The four stages of treatment (self monitoring, information giving, relaxation training and problem solving) lasted 27-37 weeks. Four of the five subjects benefited from treatment as their follow up scores met the criteria for improvement. The results allowed cautious optimism about the efficacy of cognitive behavioural techniques and the use of self report measures for people who have a learning disability, who are verbal. The value of embedding this focussed treatment within a broader therapeutic framework, to encompass a wider range of emotions and strategies to cope with stress was discussed.Quality of life and deinstitutionalisation : an examination of the effects of relocating people with learning disabilities from hospital to life in the communityWhoriskey, Margarethttps://hdl.handle.net/10023/135132019-04-01T08:53:44Z1999-04-01T00:00:00ZThe quality of life for people with learning disabilities was examined for 50 people leaving hospital to live in a range of community residences and for 50 people remaining in hospital. Individuals were followed up for up to 30 months at six monthly intervals. The social validity of quality of life assessment was examined by comparing the importance of a number of service objectives to people with and without learning disabilities. This then informed the development of two measures used to assess aspects of quality of life. A range of measures were employed to address both objective and subjective dimensions of quality of life. Five main areas were identified and examined in two studies - competence and personal growth; health and well-being; quality of care; engagement in activity and staff resident interactions. The issues reflecting some of the difficulties in assessing subjective states of people with learning disabilities are discussed. Overall there was some relatively small changes in the areas of competence and personal growth, quality of care and staff interactions for people moving from hospital to live in the community. The changes tended to occur within six months of moving with little improvement thereafter. In general, there was no change for the people remaining in hospital. Implications for the detailed examination of the effects of deinstitutionalisation are discussed.
1999-04-01T00:00:00ZWhoriskey, MargaretThe quality of life for people with learning disabilities was examined for 50 people leaving hospital to live in a range of community residences and for 50 people remaining in hospital. Individuals were followed up for up to 30 months at six monthly intervals. The social validity of quality of life assessment was examined by comparing the importance of a number of service objectives to people with and without learning disabilities. This then informed the development of two measures used to assess aspects of quality of life. A range of measures were employed to address both objective and subjective dimensions of quality of life. Five main areas were identified and examined in two studies - competence and personal growth; health and well-being; quality of care; engagement in activity and staff resident interactions. The issues reflecting some of the difficulties in assessing subjective states of people with learning disabilities are discussed. Overall there was some relatively small changes in the areas of competence and personal growth, quality of care and staff interactions for people moving from hospital to live in the community. The changes tended to occur within six months of moving with little improvement thereafter. In general, there was no change for the people remaining in hospital. Implications for the detailed examination of the effects of deinstitutionalisation are discussed.Cognitive impairments in developmental dyslexiaDuncan, Lynne G.https://hdl.handle.net/10023/135122019-04-01T08:53:00Z1992-07-01T00:00:00ZThe nature of cognitive impairments in developmental dyslexia was investigated in two studies. The issue of heterogeneity was addressed and an attempt was made to identify cognitive processes which might feature in a dimensional model of reading ability. The first study examined the hypothesis that developmental dyslexics are delayed in their general perceptual development. Phonological, visual and tactile segmentation skills were assessed together with nonword naming ability. As a group, the dyslexics were only impaired for reading age at phoneme deletion and nonword naming. However, individual variation was present within the dyslexic group. Individuals exhibiting severe impairments were identified in tests of rhyme judgement, auditory organisation and visual segmentation. The perceptual delay hypothesis received only limited confirmation. The dyslexic group was impaired at the most analytical level of phonological segmentation, but not at more holistic levels. Visual and phonological segmentation skills showed some association, but were dissociated from performance in the tactile modality. The second study further explored these findings using a new sample. This dyslexic group also suffered nonword naming impairments for reading age. However, like their reading age controls, they showed a processing advantage for onset and rime units in a phonological deletion task but not in an orthographic lexical decision task. The efficacy of long-term memory representations was assessed. Individuals within the dyslexic group displayed a very deviant performance in a repetition memory task, and the group as a whole was impaired at recognising words to which they had been repeatedly exposed. It was concluded that the difficulties experienced by individual dyslexic children were varied, and that less frequent problems were likely to be overlooked by assessing impairment in developmental dyslexia in terms of group performance. Further investigation of how visual and memory processes relate to reading development would be a worthwhile addition to the extensive work linking phonological processing with reading achievement.
1992-07-01T00:00:00ZDuncan, Lynne G.The nature of cognitive impairments in developmental dyslexia was investigated in two studies. The issue of heterogeneity was addressed and an attempt was made to identify cognitive processes which might feature in a dimensional model of reading ability. The first study examined the hypothesis that developmental dyslexics are delayed in their general perceptual development. Phonological, visual and tactile segmentation skills were assessed together with nonword naming ability. As a group, the dyslexics were only impaired for reading age at phoneme deletion and nonword naming. However, individual variation was present within the dyslexic group. Individuals exhibiting severe impairments were identified in tests of rhyme judgement, auditory organisation and visual segmentation. The perceptual delay hypothesis received only limited confirmation. The dyslexic group was impaired at the most analytical level of phonological segmentation, but not at more holistic levels. Visual and phonological segmentation skills showed some association, but were dissociated from performance in the tactile modality. The second study further explored these findings using a new sample. This dyslexic group also suffered nonword naming impairments for reading age. However, like their reading age controls, they showed a processing advantage for onset and rime units in a phonological deletion task but not in an orthographic lexical decision task. The efficacy of long-term memory representations was assessed. Individuals within the dyslexic group displayed a very deviant performance in a repetition memory task, and the group as a whole was impaired at recognising words to which they had been repeatedly exposed. It was concluded that the difficulties experienced by individual dyslexic children were varied, and that less frequent problems were likely to be overlooked by assessing impairment in developmental dyslexia in terms of group performance. Further investigation of how visual and memory processes relate to reading development would be a worthwhile addition to the extensive work linking phonological processing with reading achievement.The application of cross-cultural research in emergency service work-traumaRamsay, Robert Guyhttps://hdl.handle.net/10023/135112019-04-01T08:52:56Z1996-07-01T00:00:00ZWork-trauma, conceptually related to post-traumatic stress disorder (PTSD), can impact general pathology as well as traumatic reactivity. Whilst usually associated with the emergency services, work-trauma occurs in all personnel repetitively exposed, as part of their job, to actual or potential traumatic incidents (such as fatalities, serious injuries, fires, riots, harassment, shooting incidents, rape incidents etc.). The (limited) understanding of work-trauma is essentially predicated on mono-cultural (North American) data and approaches. Although a useful start, this does not accommodate underlying cultural differences. It is argued these differences fundamentally impact reliability. Two approaches are used here to begin the application of cross-cultural factors to work-trauma: 1. Using sources based on Hofstede's cultural differences in individualism/collectivism, masculinity/feminism, power distance, and uncertainty avoidance, a link is established with certain stages of the eco-systemic model of traumatic reaction (Peterson et al, 1991). 2. A detailed review of the emergency service environment including examination stressors, call-out rates, and general pressure to perform as well as broader social differences in economic conditions, working hours, quality of life and several other factors quantifies the extensive differences researchers need to acknowledge. Using unique data from three cultural settings (Japan, Hong Kong and the UK), preliminary analysis suggests nine variables consistently associate with work-trauma symptomatology: age, child-bearing status, usual alcohol consumption, change in alcohol consumption, exercise frequency, social support from a partner, social support from a close friend, contemplation of counselling, and action on counselling. When applied to a model, however, cultural variations in were large. This begins to suggest diverse cultural experiences are impacting work-trauma. Although phenomena such as resistance to counselling, the 'macho ethic' and alcohol habits within the emergency services are - as expected - culturally consistent, this is in itself inadequate for understanding work-trauma. At a theoretical level, researchers need to further explore the documented aspects of the emergency service and social environments with a view to developing instruments which measure cultural diversity. At a practical level, given the culturally consistent alcohol habits in emergency services, future researchers should consider the use of emergency service personnel as front-line diagnosticians of work-trauma. Counselling needs are assessed in this light.
1996-07-01T00:00:00ZRamsay, Robert GuyWork-trauma, conceptually related to post-traumatic stress disorder (PTSD), can impact general pathology as well as traumatic reactivity. Whilst usually associated with the emergency services, work-trauma occurs in all personnel repetitively exposed, as part of their job, to actual or potential traumatic incidents (such as fatalities, serious injuries, fires, riots, harassment, shooting incidents, rape incidents etc.). The (limited) understanding of work-trauma is essentially predicated on mono-cultural (North American) data and approaches. Although a useful start, this does not accommodate underlying cultural differences. It is argued these differences fundamentally impact reliability. Two approaches are used here to begin the application of cross-cultural factors to work-trauma: 1. Using sources based on Hofstede's cultural differences in individualism/collectivism, masculinity/feminism, power distance, and uncertainty avoidance, a link is established with certain stages of the eco-systemic model of traumatic reaction (Peterson et al, 1991). 2. A detailed review of the emergency service environment including examination stressors, call-out rates, and general pressure to perform as well as broader social differences in economic conditions, working hours, quality of life and several other factors quantifies the extensive differences researchers need to acknowledge. Using unique data from three cultural settings (Japan, Hong Kong and the UK), preliminary analysis suggests nine variables consistently associate with work-trauma symptomatology: age, child-bearing status, usual alcohol consumption, change in alcohol consumption, exercise frequency, social support from a partner, social support from a close friend, contemplation of counselling, and action on counselling. When applied to a model, however, cultural variations in were large. This begins to suggest diverse cultural experiences are impacting work-trauma. Although phenomena such as resistance to counselling, the 'macho ethic' and alcohol habits within the emergency services are - as expected - culturally consistent, this is in itself inadequate for understanding work-trauma. At a theoretical level, researchers need to further explore the documented aspects of the emergency service and social environments with a view to developing instruments which measure cultural diversity. At a practical level, given the culturally consistent alcohol habits in emergency services, future researchers should consider the use of emergency service personnel as front-line diagnosticians of work-trauma. Counselling needs are assessed in this light.Psychological aspects of cerebral palsy.Cockburn, June Margarethttps://hdl.handle.net/10023/134422019-04-01T08:53:22Z1959-01-01T00:00:00Z1959-01-01T00:00:00ZCockburn, June MargaretThe cognitive and motor deficits of Parkinson's disease.Gauntlett-Gilbert, Jeremyhttps://hdl.handle.net/10023/134412019-04-01T08:52:25Z1999-03-01T00:00:00ZDeficits of attentional and motor set that are seen in patients with PD were investigated in the research reported in this thesis. A deficit of attentional set is a failure of selective attention to one aspect of a complex stimulus. Deficits of motor set manifest as an inability to form a state of motor 'readiness' that can speed movement initiation. Attentional set was investigated with tasks that require patients to shift attention between perceptual dimensions (extradimensional - ED - shifting tasks), and motor set was studied using reaction time (RT) tasks. Study 1 rejected the hypothesis that the mechanism of 'learned irrelevance' causes ED shift deficits in patients with PD. Studies 2 and 3 confirmed that learned irrelevance also plays no role in determining the difficulty of ED shifts in healthy subjects. The experimental manipulation used in Study 4 succeeded in creating changes in scores that resembled those seen in patients with PD. Thus, it appears that patients with PD may have a deficit similar to that induced by the experimental manipulation - that is, an inability to attend to all dimensions present when hypothesis testing after an ED shift. A quantitative analysis of past RT studies of PD showed that the ability to speed movement initiation when given advance information about an upcoming movement - a form of motor set - is intact in patients with PD. In contrast, the motor set that underlies rapid simple RT performance is consistently dysfunctional in patients with PD. Study 5 investigated temporal and spatial motor set in PD, finding that these two mechanisms are functionally separate and that temporal motor set is intact in PD. A final study (Study 6) investigated the cognitive consequences of a novel neurosurgical treatment for PD, finding it to be largely a neuropsychologically 'safe' procedure.
1999-03-01T00:00:00ZGauntlett-Gilbert, JeremyDeficits of attentional and motor set that are seen in patients with PD were investigated in the research reported in this thesis. A deficit of attentional set is a failure of selective attention to one aspect of a complex stimulus. Deficits of motor set manifest as an inability to form a state of motor 'readiness' that can speed movement initiation. Attentional set was investigated with tasks that require patients to shift attention between perceptual dimensions (extradimensional - ED - shifting tasks), and motor set was studied using reaction time (RT) tasks. Study 1 rejected the hypothesis that the mechanism of 'learned irrelevance' causes ED shift deficits in patients with PD. Studies 2 and 3 confirmed that learned irrelevance also plays no role in determining the difficulty of ED shifts in healthy subjects. The experimental manipulation used in Study 4 succeeded in creating changes in scores that resembled those seen in patients with PD. Thus, it appears that patients with PD may have a deficit similar to that induced by the experimental manipulation - that is, an inability to attend to all dimensions present when hypothesis testing after an ED shift. A quantitative analysis of past RT studies of PD showed that the ability to speed movement initiation when given advance information about an upcoming movement - a form of motor set - is intact in patients with PD. In contrast, the motor set that underlies rapid simple RT performance is consistently dysfunctional in patients with PD. Study 5 investigated temporal and spatial motor set in PD, finding that these two mechanisms are functionally separate and that temporal motor set is intact in PD. A final study (Study 6) investigated the cognitive consequences of a novel neurosurgical treatment for PD, finding it to be largely a neuropsychologically 'safe' procedure.Immunological investigation in multiple sclerosisSouberbielle, Bernardhttps://hdl.handle.net/10023/134402019-04-01T08:53:14Z1993-07-01T00:00:00ZIn this thesis, immunological parameters in multiple sclerosis patients (MS) have been examined and techniques contributing to the study of these aspects have been developed. The epidemiology of MS suggests that both environmental and genetic factors contribute to the disease process. According to a widespread theory, an autoimmune reaction leading to demyelination could be induced, in genetically determined individuals, by an infectious agent (s) e.g a paramyxovirus or a retrovirus. In the first part of the thesis, the oligoclonal immunoglobulin (Igs) in the CSF of MS patients in relation to the paramyxovirus SV5 were studied. This was to complement an initial observation made in the department that a significant proportion of cerebrospinal fluids (CSF) could have oligoclonal bands directly acting against antigens (Ags) of this virus. In the second part of the thesis, techniques were developed for the analysis of proliferative capacity of peripheral lymphocytes of MS and control patients using possible MS autoantigens viz myelin and brain vessels. The humoral response against these Ags was also assessed by immunoblotting using MS, neurological and normal control patients. In parallel and in the view to obtaining antigens for the immunological studies, techniques for the purification and characterisation of human brain vessels from post mortem brains were assessed and attempts to culture human brain endothelial cell lines were made. (Abstract shortened by ProQuest.)
1993-07-01T00:00:00ZSouberbielle, BernardIn this thesis, immunological parameters in multiple sclerosis patients (MS) have been examined and techniques contributing to the study of these aspects have been developed. The epidemiology of MS suggests that both environmental and genetic factors contribute to the disease process. According to a widespread theory, an autoimmune reaction leading to demyelination could be induced, in genetically determined individuals, by an infectious agent (s) e.g a paramyxovirus or a retrovirus. In the first part of the thesis, the oligoclonal immunoglobulin (Igs) in the CSF of MS patients in relation to the paramyxovirus SV5 were studied. This was to complement an initial observation made in the department that a significant proportion of cerebrospinal fluids (CSF) could have oligoclonal bands directly acting against antigens (Ags) of this virus. In the second part of the thesis, techniques were developed for the analysis of proliferative capacity of peripheral lymphocytes of MS and control patients using possible MS autoantigens viz myelin and brain vessels. The humoral response against these Ags was also assessed by immunoblotting using MS, neurological and normal control patients. In parallel and in the view to obtaining antigens for the immunological studies, techniques for the purification and characterisation of human brain vessels from post mortem brains were assessed and attempts to culture human brain endothelial cell lines were made. (Abstract shortened by ProQuest.)Investigations into the cognitive functioning of subjects with epilepsy in relation to anticonvulsant medication.Garvey, Kayhttps://hdl.handle.net/10023/134392019-04-01T08:53:23Z1995-07-01T00:00:00ZThe literature on epilepsy is vast. The first review in this thesis presented a short introduction to the nature of the disease and its relationship to cognitive functioning. The pharmacological treatment of epilepsy by three major anticonvulsant drugs (carbamazepine, sodium valproate and phenytoin) and the possibility of effects of this treatment on cognitive functioning is presented in the second review. This review identified certain areas of cognitive functioning, for example memory, that warrant further investigation. A third review discussed those relevant areas of cognitive functioning, including both theory and suitable methodologies for investigating working memory and attentional resources. The three review chapters provided theoretical and practical frameworks to carry out investigations of the effects of anticonvulsant medication on cognitive functioning. Four experimental studies are presented. The design of the first study was a between-groups comparison, in which four groups of subjects with epilepsy (three on monotherapy and a polytherapy group) and a control group were compared on a battery of memory tests. The only significant group difference was the impaired performance of the polytherapy group compared to the control group. The second study was a between-groups comparison of the performance of four groups with epilepsy (three on monotherapy and one untreated group) and one control group, on a new battery of tests measuring working memory and attentional resources. The sodium valproate group was significantly impaired on two of the working memory tasks compared to the control group. No other group differences were found and increasing task complexity did not significantly affect the drug groups compared to the control group. Of interest in both study one and two was the consistent pattern of results across the test batteries, which did not produce significant differences between the groups. Both studies revealed large variance in the clinical subject groups, such that a number of the subjects with epilepsy, particularly on sodium valproate and phenytoin were performing very poorly compared to control group performance. No obvious reasons were identified for the poor performance. Study three investigated the effects on cognitive functioning of a new anticonvulsant drug (Lamotrogine). The clinical subject group was very impaired compared to a control group, and a small amount of further impairment was present after the subjects began taking Lamotrogine. The fourth study piloted tests designed to measure aspects of perceptual and motor functioning. The only significant result obtained was that the polytherapy group performed significantly worse compared to the control and the monotherapy groups on simple reaction time tasks. The focus of the discussion chapter was a summary of the important aspects of the studies in the thesis with comparisons made to other studies in the published literature.
1995-07-01T00:00:00ZGarvey, KayThe literature on epilepsy is vast. The first review in this thesis presented a short introduction to the nature of the disease and its relationship to cognitive functioning. The pharmacological treatment of epilepsy by three major anticonvulsant drugs (carbamazepine, sodium valproate and phenytoin) and the possibility of effects of this treatment on cognitive functioning is presented in the second review. This review identified certain areas of cognitive functioning, for example memory, that warrant further investigation. A third review discussed those relevant areas of cognitive functioning, including both theory and suitable methodologies for investigating working memory and attentional resources. The three review chapters provided theoretical and practical frameworks to carry out investigations of the effects of anticonvulsant medication on cognitive functioning. Four experimental studies are presented. The design of the first study was a between-groups comparison, in which four groups of subjects with epilepsy (three on monotherapy and a polytherapy group) and a control group were compared on a battery of memory tests. The only significant group difference was the impaired performance of the polytherapy group compared to the control group. The second study was a between-groups comparison of the performance of four groups with epilepsy (three on monotherapy and one untreated group) and one control group, on a new battery of tests measuring working memory and attentional resources. The sodium valproate group was significantly impaired on two of the working memory tasks compared to the control group. No other group differences were found and increasing task complexity did not significantly affect the drug groups compared to the control group. Of interest in both study one and two was the consistent pattern of results across the test batteries, which did not produce significant differences between the groups. Both studies revealed large variance in the clinical subject groups, such that a number of the subjects with epilepsy, particularly on sodium valproate and phenytoin were performing very poorly compared to control group performance. No obvious reasons were identified for the poor performance. Study three investigated the effects on cognitive functioning of a new anticonvulsant drug (Lamotrogine). The clinical subject group was very impaired compared to a control group, and a small amount of further impairment was present after the subjects began taking Lamotrogine. The fourth study piloted tests designed to measure aspects of perceptual and motor functioning. The only significant result obtained was that the polytherapy group performed significantly worse compared to the control and the monotherapy groups on simple reaction time tasks. The focus of the discussion chapter was a summary of the important aspects of the studies in the thesis with comparisons made to other studies in the published literature.A new tritium monitor design based on plasma source ion implantation techniqueNassar, Rafat Mohammadhttps://hdl.handle.net/10023/133732019-04-01T08:52:40Z1997-06-01T00:00:00ZTritium is an important isotope of hydrogen. The availability of tritium in our environment is manifest through both natural and artificial sources. Consequently, the requirement for tritium handling and usage will continue to increase in the future. An important future contributor is nuclear fusion power plants and facilities. Essential safety regulations and procedures require effective monitoring and measurements of tritium concentrations in workplaces. The unique characteristics of tritium impose an important role on the criteria for its detection and measurement. As tritium decays by the emission of soft beta particles, maximum 18 keV, it cannot be readily detected by commonly used detectors. Specially built monitors are required. Additional complications occur due to the presence of other radioactive isotopes or ambient radiation fields and because of the high diffusivity of tritium. When it is in oxidized form it is 25000 times more hazardous biologically than when in elemental form. Therefore, contamination of the monitor is expected and compound specific monitors are important. A summary is given of the various well known methods of detecting tritium-in-air. This covers the direct as well as the indirect measuring techniques, although each has been continually improved and further developed, nevertheless, each has its own limitations. Ionization chambers cannot discriminate against airborne P emitters. Proportional counters have a narrow operating range, 3-4 decades, and have poor performance in relatively high humid environments and require a dry counting gas. Liquid scintillation counters are sensitive, but inspection of the sample is slow and they produce chemical liquid waste. A new way to improve the sensitivity of detecting tritium with plastic scintillators has been developed. The technique is based on a non-line-of-sight implantation of tritium ions into a 20 mum plastic scintillator using a plasma source ion implantation (PSII) technique, This type of source is different, superior to the line-of-sight implantation and requires no additional beam handling. It is capable of implanting ion species in a broad beam configuration into the entire surface of a target. The technique requires a special ion source with special characteristics of the type obtained from a surfatron plasma source. This ion source has a large high ion density plasma with minimum contamination and produces ions of low temperature. It was constructed to ionize the sampled air and to produce a plasma over a wide range of pressure, 4-0.1 mTorr. A plasma source ion implantation cell was designed and constructed using mathematical modeling with personal computer, to optimize the essential variables of the design and to estimate the implantation rate under different operation conditions. Also, a high voltage pulse modulator was designed and constructed to produce a series of 10 musec pulses (up to 2 MHz) with a maximum magnitude of -60 kV. The developed device was capable of ionizing air samples and implanting the resulting ions into a plastic scintillator. Two different methods to enhance the collection and deposition of the tritium ions, have been proposed and assessed. A movable prototype device for monitoring environmental tritium in air has been designed and constructed. Although this prototype was not fully tested, the primary calculations have shown that measurable concentrations of tritium ions can be collected from an air sample, with tritium activity ranging from 0.3 Bq/cm3 down to 0.03 mBq/cm3, in a short time, to the order of seconds, on-line. This sensitivity fulfills the requirement for environmental monitoring.
1997-06-01T00:00:00ZNassar, Rafat MohammadTritium is an important isotope of hydrogen. The availability of tritium in our environment is manifest through both natural and artificial sources. Consequently, the requirement for tritium handling and usage will continue to increase in the future. An important future contributor is nuclear fusion power plants and facilities. Essential safety regulations and procedures require effective monitoring and measurements of tritium concentrations in workplaces. The unique characteristics of tritium impose an important role on the criteria for its detection and measurement. As tritium decays by the emission of soft beta particles, maximum 18 keV, it cannot be readily detected by commonly used detectors. Specially built monitors are required. Additional complications occur due to the presence of other radioactive isotopes or ambient radiation fields and because of the high diffusivity of tritium. When it is in oxidized form it is 25000 times more hazardous biologically than when in elemental form. Therefore, contamination of the monitor is expected and compound specific monitors are important. A summary is given of the various well known methods of detecting tritium-in-air. This covers the direct as well as the indirect measuring techniques, although each has been continually improved and further developed, nevertheless, each has its own limitations. Ionization chambers cannot discriminate against airborne P emitters. Proportional counters have a narrow operating range, 3-4 decades, and have poor performance in relatively high humid environments and require a dry counting gas. Liquid scintillation counters are sensitive, but inspection of the sample is slow and they produce chemical liquid waste. A new way to improve the sensitivity of detecting tritium with plastic scintillators has been developed. The technique is based on a non-line-of-sight implantation of tritium ions into a 20 mum plastic scintillator using a plasma source ion implantation (PSII) technique, This type of source is different, superior to the line-of-sight implantation and requires no additional beam handling. It is capable of implanting ion species in a broad beam configuration into the entire surface of a target. The technique requires a special ion source with special characteristics of the type obtained from a surfatron plasma source. This ion source has a large high ion density plasma with minimum contamination and produces ions of low temperature. It was constructed to ionize the sampled air and to produce a plasma over a wide range of pressure, 4-0.1 mTorr. A plasma source ion implantation cell was designed and constructed using mathematical modeling with personal computer, to optimize the essential variables of the design and to estimate the implantation rate under different operation conditions. Also, a high voltage pulse modulator was designed and constructed to produce a series of 10 musec pulses (up to 2 MHz) with a maximum magnitude of -60 kV. The developed device was capable of ionizing air samples and implanting the resulting ions into a plastic scintillator. Two different methods to enhance the collection and deposition of the tritium ions, have been proposed and assessed. A movable prototype device for monitoring environmental tritium in air has been designed and constructed. Although this prototype was not fully tested, the primary calculations have shown that measurable concentrations of tritium ions can be collected from an air sample, with tritium activity ranging from 0.3 Bq/cm3 down to 0.03 mBq/cm3, in a short time, to the order of seconds, on-line. This sensitivity fulfills the requirement for environmental monitoring.An improved system of damage limitation for better risk control in radiological protection near environmental level.Salikin, Md. Saionhttps://hdl.handle.net/10023/133722019-04-01T08:53:33Z1995-07-01T00:00:00ZIn radiological protection, models are used to assess radiation risk by means of extrapolation from high dose and dose rate to low dose and dose rate. In this thesis five main biophysical models of radiation action have been evaluated, appraised and inter-compared. The five models are lethal and potentially lethal (LPL) by Curtis, pairwise lesion interaction (PLI) by Harder, cellular track structure (CTS) by Katz, hit size effectiveness (HSE) by Bond and Varma and track core (TC) by Watt. Each model has been developed based on certain underlying mechanisms or phenomena, to permit interpretation and prediction on the induction of a specified biological endpoint such as cell reproductive death, chromosome aberrations and mutations. Biological systems of interest are, for example, mammalian cells containing deoxyribonucleic acid (DNA). Evidence is mounting that double strand breaks in the DNA are the critical lesions for various biological end points. To proceed with this work the TC model has been chosen. Cancer induction by ionising radiation is the stochastic effect of prime concern in radiological protection. Cancer induction cannot be avoided entirely but its frequency of occurrence may be reduced to acceptable level by lowering the amount of radiation received. The methods of assessment developed by ICRP, in terms of the cancer risk coefficients, are presented in this thesis. In the conventional (legal) system of dosimetry, radiation is quantified by the amount of energy absorbed per unit mass of tissue. Quality factors, superseded by radiation weighting factors, are needed to account for the quality dependence on radiation type. As an alternative, a new dosimetry system is proposed here which is based on the mean free path for primary ionisation along particle tracks and the integral fluence generated by the radiation field, whether directly or indirectly ionising radiation. From the study of cellular data, the mean free path for primary ionisation along particle tracks (lambda) emerges as a parameter which best unifies biological damage data. Radiation effect is found to depend, not on the energy transferred but to depend mainly on the frequency and spatial correlation of interactions. Maximum effect occurs when lambda is equal to lambda0 (2 nanometre, nm). The term 'Absolute Biological Effectiveness' (ABE) is introduced as a parameter which indicates the probability to induce a specified effect, per unit incident fluence. In this endeavour, only direct effects are considered in deriving ABE values for various radiations. However other factors such as indirect effects, inter-track action, repair processes and radiation rate, can be incorporated later if required, in the derivation of ABE. ABE values for photons up to 60Co i.e 1253 keV and neutrons up to 105 keV, have been calculated and presented in this thesis. An attempt has been made to re-express the cancer risk coefficients, derived by ICRP, in the new dosimetry system, in terms of the ABE (Absolute Biological Effectiveness). The hypothesis put forward in this thesis is that the induction of a specified biological-end-point in a biological system due to ionising radiations, is determined not by the amount of energy absorbed per unit mass (dose), but rather by the number of events (ionizations) spatially correlated, along the primary radiation track. Based on this hypothesis, a new unified dosimetry system, independent of radiation type, is proposed. Suggestions are made for possible measuring instruments which have the equivalent response characteristics, namely maximum efficiency of detection for the mean free path Success in devising such types of instrument would ensure the practicability of the new dosimetry system, in operational radiological protection.
1995-07-01T00:00:00ZSalikin, Md. SaionIn radiological protection, models are used to assess radiation risk by means of extrapolation from high dose and dose rate to low dose and dose rate. In this thesis five main biophysical models of radiation action have been evaluated, appraised and inter-compared. The five models are lethal and potentially lethal (LPL) by Curtis, pairwise lesion interaction (PLI) by Harder, cellular track structure (CTS) by Katz, hit size effectiveness (HSE) by Bond and Varma and track core (TC) by Watt. Each model has been developed based on certain underlying mechanisms or phenomena, to permit interpretation and prediction on the induction of a specified biological endpoint such as cell reproductive death, chromosome aberrations and mutations. Biological systems of interest are, for example, mammalian cells containing deoxyribonucleic acid (DNA). Evidence is mounting that double strand breaks in the DNA are the critical lesions for various biological end points. To proceed with this work the TC model has been chosen. Cancer induction by ionising radiation is the stochastic effect of prime concern in radiological protection. Cancer induction cannot be avoided entirely but its frequency of occurrence may be reduced to acceptable level by lowering the amount of radiation received. The methods of assessment developed by ICRP, in terms of the cancer risk coefficients, are presented in this thesis. In the conventional (legal) system of dosimetry, radiation is quantified by the amount of energy absorbed per unit mass of tissue. Quality factors, superseded by radiation weighting factors, are needed to account for the quality dependence on radiation type. As an alternative, a new dosimetry system is proposed here which is based on the mean free path for primary ionisation along particle tracks and the integral fluence generated by the radiation field, whether directly or indirectly ionising radiation. From the study of cellular data, the mean free path for primary ionisation along particle tracks (lambda) emerges as a parameter which best unifies biological damage data. Radiation effect is found to depend, not on the energy transferred but to depend mainly on the frequency and spatial correlation of interactions. Maximum effect occurs when lambda is equal to lambda0 (2 nanometre, nm). The term 'Absolute Biological Effectiveness' (ABE) is introduced as a parameter which indicates the probability to induce a specified effect, per unit incident fluence. In this endeavour, only direct effects are considered in deriving ABE values for various radiations. However other factors such as indirect effects, inter-track action, repair processes and radiation rate, can be incorporated later if required, in the derivation of ABE. ABE values for photons up to 60Co i.e 1253 keV and neutrons up to 105 keV, have been calculated and presented in this thesis. An attempt has been made to re-express the cancer risk coefficients, derived by ICRP, in the new dosimetry system, in terms of the ABE (Absolute Biological Effectiveness). The hypothesis put forward in this thesis is that the induction of a specified biological-end-point in a biological system due to ionising radiations, is determined not by the amount of energy absorbed per unit mass (dose), but rather by the number of events (ionizations) spatially correlated, along the primary radiation track. Based on this hypothesis, a new unified dosimetry system, independent of radiation type, is proposed. Suggestions are made for possible measuring instruments which have the equivalent response characteristics, namely maximum efficiency of detection for the mean free path Success in devising such types of instrument would ensure the practicability of the new dosimetry system, in operational radiological protection.Charge transport in liquid hydrocarbons for microdosimetryChaar, Mamdouhhttps://hdl.handle.net/10023/133672019-04-01T08:53:11Z1998-06-01T00:00:00ZDuring the last two decades there has been growing interest in the application of organic dielectric liquids for dosimetry of ionizing radiations. The main problem associated with the liquid application in radiation detectors has been the difficulty in securing saturation charge collection and controlled charge multiplication to permit operation in the ionization chamber and proportional counter modes. In an attempt to understand better the fundamental mechanisms involved in the limitation to charge collection an extensive review has been made of the published theoretical and experimental research. The theoretical work attributes the unattainability of saturation charge collection to losses caused by different types of recombination depending on the initial separation of ions liberated and on the magnitude of the applied electric field. None of the presented theories is found to be fully consistent with the reported experimental results obtained for a range of different di-electric liquids, especially in high field regions. Liquid hydrocarbons, especially those characterised by high charge mobility and high yield of ions, have been widely investigated experimentally to explore the mechanisms responsible. The experimental measurements are found to be strongly dependent on: the purity of the liquids, their chemical structure, the type of materials used for the electrodes in contact with the liquid and on the temperature. These conclusions reflect inadequacies both in the theoretical knowledge of charge transport in liquids and in the practical difficulties of measurement which indicate the need for more detailed experimental investigation. The origin of the natural intrinsic dark current in liquids is found to be due to the presence of impurities; the effect of cosmic-ray interactions; and the presence of radioactivity in the construction materials of the detector. Upon application of high electric fields other factors such as electron emission, molecular dissociation and field ionization become significant. The extensive range of results reported on transport properties (mobility, free ion-yield, conduction band energy, di-electric strength, and theoretical W-values) of charge earners in liquid hydrocarbons and liquified rare-gases, and their dependence on the electric field and temperature have been compiled into tabulated form in appendix B to provide a ready reference. New experimental work, aimed at assessing the role and the key factors involved, was conducted with two separate ionization chambers filled with liquid tetramethylsilane (TMS). Information was obtained on the dependence of the current-field characteristic, for the dark and ionization currents, on various parameters such as purity, electrode separation, surface asperities, electrode construction material, and the charge collection area. For the ionization current, the dependence on the radiation intensity, produced with a 4 mCi source of 57Co of y-rays, was also measured. Liquid purity was confirmed to be very important. Chemical and electrical purification, could lead to orders of magnitude reduction in the background dark current. Tests, made to assess the efficiency of ion collection in liquid TMS, indicated the need for much larger, and more uniform, electric fields. These were achieved by fitting electrodes made from tissue-equivalent plastic. The improved surface smoothness of the latter was found to improve the current-to-noise ratio by a factor of 2-3 orders of magnitude. From the results of the present investigation at fields ? 500 kV/cm it was concluded that the saturation collection of charge was attainable. Limitation to achieving saturation is discussed in terms of charge multiplication produced inside localised gas bubbles on the electrode surfaces. Field induced polarization of liquid molecules could be a contributing factor at high fields. There appears to be realistic prospects of achieving saturation collection of charge, and possibly proportional multiplication, by appropriate design using advanced technology to ensure ultra-smooth surfaces and uniform electric fields.
1998-06-01T00:00:00ZChaar, MamdouhDuring the last two decades there has been growing interest in the application of organic dielectric liquids for dosimetry of ionizing radiations. The main problem associated with the liquid application in radiation detectors has been the difficulty in securing saturation charge collection and controlled charge multiplication to permit operation in the ionization chamber and proportional counter modes. In an attempt to understand better the fundamental mechanisms involved in the limitation to charge collection an extensive review has been made of the published theoretical and experimental research. The theoretical work attributes the unattainability of saturation charge collection to losses caused by different types of recombination depending on the initial separation of ions liberated and on the magnitude of the applied electric field. None of the presented theories is found to be fully consistent with the reported experimental results obtained for a range of different di-electric liquids, especially in high field regions. Liquid hydrocarbons, especially those characterised by high charge mobility and high yield of ions, have been widely investigated experimentally to explore the mechanisms responsible. The experimental measurements are found to be strongly dependent on: the purity of the liquids, their chemical structure, the type of materials used for the electrodes in contact with the liquid and on the temperature. These conclusions reflect inadequacies both in the theoretical knowledge of charge transport in liquids and in the practical difficulties of measurement which indicate the need for more detailed experimental investigation. The origin of the natural intrinsic dark current in liquids is found to be due to the presence of impurities; the effect of cosmic-ray interactions; and the presence of radioactivity in the construction materials of the detector. Upon application of high electric fields other factors such as electron emission, molecular dissociation and field ionization become significant. The extensive range of results reported on transport properties (mobility, free ion-yield, conduction band energy, di-electric strength, and theoretical W-values) of charge earners in liquid hydrocarbons and liquified rare-gases, and their dependence on the electric field and temperature have been compiled into tabulated form in appendix B to provide a ready reference. New experimental work, aimed at assessing the role and the key factors involved, was conducted with two separate ionization chambers filled with liquid tetramethylsilane (TMS). Information was obtained on the dependence of the current-field characteristic, for the dark and ionization currents, on various parameters such as purity, electrode separation, surface asperities, electrode construction material, and the charge collection area. For the ionization current, the dependence on the radiation intensity, produced with a 4 mCi source of 57Co of y-rays, was also measured. Liquid purity was confirmed to be very important. Chemical and electrical purification, could lead to orders of magnitude reduction in the background dark current. Tests, made to assess the efficiency of ion collection in liquid TMS, indicated the need for much larger, and more uniform, electric fields. These were achieved by fitting electrodes made from tissue-equivalent plastic. The improved surface smoothness of the latter was found to improve the current-to-noise ratio by a factor of 2-3 orders of magnitude. From the results of the present investigation at fields ? 500 kV/cm it was concluded that the saturation collection of charge was attainable. Limitation to achieving saturation is discussed in terms of charge multiplication produced inside localised gas bubbles on the electrode surfaces. Field induced polarization of liquid molecules could be a contributing factor at high fields. There appears to be realistic prospects of achieving saturation collection of charge, and possibly proportional multiplication, by appropriate design using advanced technology to ensure ultra-smooth surfaces and uniform electric fields.Microdosimetry of photoneutrons around medical linear accelerators.Crossman, John S. P.https://hdl.handle.net/10023/133662019-04-01T08:53:24Z1997-06-01T00:00:00ZPhotoneutrons produced in the vicinity of medical linear accelerators for therapy, constitute a hazard which is difficult to assess and monitor. The aims of the project were to develop new techniques, using microdosimetry, which would be suitable for the improved quality control of pulsed photon beams and for the assessment of the associated photoneutron hazard in typical treatment facilities from the perspective of the patients and staff. The measurements of photoneutron yields and equivalent doses were obtained using activation analysis detectors around a 10 MV LINAC. To obtain adequate statistical precision, an optimum thickness of 2.5 cm of polyethylene was used that doubled the detector's sensitivity. This enabled the yields and spatial distribution of the low intensity field to be recorded. Photoneutron equivalent dose-rates of up to 0.104 Sv.h-1, or 0.1% of the useful photon dose- rates, were measured. In the literature, however, it was found that equivalent dose-rates could reach as high as 1 % of the useful photon treatment dose-rate for machines operating at X ray energies of ≥18 MV. Thus it is recommended that to uphold the principle of ALARA, such high energies (≥18 MV) should only be used when no lower energy machine is available. Microdosimetry with a tissue equivalent proportional counter (TEPC) microdosimeter, enabled the photoneutron contribution to the quality spectrum to be identified in the maze to the treatment room of the 10 MV LIN AC, and the photoneutrons there were assigned a radiation weighting factor of 20. The known problems concerning the rf interference and very high pulsed dose-rates inside the treatment room proved too severe to obtain meaningful results with the TEPC. The microdosimeter did however provide useful diagnostic information. Furthermore, a novel calibration technique for TEPC's was developed and an established one, the proton-edge method, was improved. A new approach was adopted to conduct microdosimetry in the vicinity of medical accelerators. This involved the design of a condensed phase microdosimeter comprising, a miniature CsI(T1) scintillator coupled to an optical fibre 20 m long, for conducting in-beam, on-line measurements of quality spectra. However, Cerenkov light and scintillation light produced in the optical fibre by the radiation fields was the cause of strong interference that has yet to be overcome. The application of the microdosimeter, which is still under development, to brachytherapy is proposed for in-vivo measurements.
1997-06-01T00:00:00ZCrossman, John S. P.Photoneutrons produced in the vicinity of medical linear accelerators for therapy, constitute a hazard which is difficult to assess and monitor. The aims of the project were to develop new techniques, using microdosimetry, which would be suitable for the improved quality control of pulsed photon beams and for the assessment of the associated photoneutron hazard in typical treatment facilities from the perspective of the patients and staff. The measurements of photoneutron yields and equivalent doses were obtained using activation analysis detectors around a 10 MV LINAC. To obtain adequate statistical precision, an optimum thickness of 2.5 cm of polyethylene was used that doubled the detector's sensitivity. This enabled the yields and spatial distribution of the low intensity field to be recorded. Photoneutron equivalent dose-rates of up to 0.104 Sv.h-1, or 0.1% of the useful photon dose- rates, were measured. In the literature, however, it was found that equivalent dose-rates could reach as high as 1 % of the useful photon treatment dose-rate for machines operating at X ray energies of ≥18 MV. Thus it is recommended that to uphold the principle of ALARA, such high energies (≥18 MV) should only be used when no lower energy machine is available. Microdosimetry with a tissue equivalent proportional counter (TEPC) microdosimeter, enabled the photoneutron contribution to the quality spectrum to be identified in the maze to the treatment room of the 10 MV LIN AC, and the photoneutrons there were assigned a radiation weighting factor of 20. The known problems concerning the rf interference and very high pulsed dose-rates inside the treatment room proved too severe to obtain meaningful results with the TEPC. The microdosimeter did however provide useful diagnostic information. Furthermore, a novel calibration technique for TEPC's was developed and an established one, the proton-edge method, was improved. A new approach was adopted to conduct microdosimetry in the vicinity of medical accelerators. This involved the design of a condensed phase microdosimeter comprising, a miniature CsI(T1) scintillator coupled to an optical fibre 20 m long, for conducting in-beam, on-line measurements of quality spectra. However, Cerenkov light and scintillation light produced in the optical fibre by the radiation fields was the cause of strong interference that has yet to be overcome. The application of the microdosimeter, which is still under development, to brachytherapy is proposed for in-vivo measurements.Specification of the quality of ionising radiations for unified dosimetry in radiobiology and radiological protectionAlkharam, Ali Salemhttps://hdl.handle.net/10023/133602019-04-01T08:53:27Z1997-06-01T00:00:00ZIt is widely agreed in radiobiological and biophysical research that the DNA is the dominant target which can lead to terminal biological damage in the form of cancer or cell death. A main objective in radiation protection is to set the limits of the possible harmful effects to the general population exposed to ionising radiation at low level (environmental level). The initial slope of the dose-response curve is found to be an appropriate parameter to achieve this objective. Bench mark data sets of the initial effects of ionising radiation on cells in vitro were formed which include both physical characterisation of the radiation and the radiobiological parameters. These data-bases include the mammalian cell end-points: cellular inactivation, chromosome dicentrics, HPRT mutations and oncogenic transformations. On the molecular scale, the databases include single-strand and double strand breaks induced in the DNA of both mammalian and non-mammalian cells. Analysis of bio-effect mechanisms of damage to mammalian cells in terms of the quality parameter 'mean free path for linear primary ionisation' for ionising radiation, strongly suggest that there is a common mechanism for the biological endpoints of dicentrics, mutations, and oncogemc transformations. A unified response is obtained for all types of heavy ions and all cells which show: a common inflection point at inter-spacing distance equivalent to lambda0 = 1.4+/- 0.5 nm, a saturation region at lambda < lambda0 and almost constant slope for lambda < lambda0. The lethal lesions are identified as dsb's in the intracellular DNA. It follows that radiation risk factors can be determined on the basis of simple ratios to the inactivation cross sections. The size of these genes are found to be in close proximity to the optimised saturation levels. The probabilities of risk with respect to inactivation, for chromosome dicentrics, oncogenic transformations, and mutations of the HPRT gene are respectively 0.18, 1.6 x 10<super>-4 </super>and 2.91 x 10<super>-5</super>. The same analysis shows that sparsely ionising radiations, which have lower effect cross-sections by an order of magnitude or more, can never reach saturation. Analysis of the molecular dsb's of DNA produced in mammalian cells by heavy ions shows a lower saturation cross-section of 0.83 mum2 which may be compared with the geometrical cross-section of 3.5 mum2. The difference is attributed to a higher packing factor. Calculations using earlier endpoint saturation cross-sections show that 4 dsb's in DNA of a human lymphocyte cell are needed to induce a chromosome dicentric, 100 dsb's in DNA of a C3H10T1/2 cell are needed to inactivate an oncogene, and 3500 dsb's in DNA of a V79 cell are needed on average to delete an HPRT mutant. The feasibility to design a new dosimetric system which would have a unified response, as described above, is considered. NE102A plastic scintillators of 20 mum thickness are found to be a potentially good prospect for detecting weak ionising radiation. By adjusting the concentration of the activator, the mean of the random distance between centres can be modified to simulate the strand-pair distribution of the DNA in mammalian cells. Thus it is possible to simulate the yield of dsb's in DNA damage as those paired centres spaced by about 1.8 nm and to distinguish them from other unwanted pairs of activated sites with different spacings. Using a 60Co-y radiation source, and starting from the knowledge of the equilibrium slowing down spectrum of electrons in plastic scintillator, the yields of photons and paired events with an inter-spacing distance of - 1.8 nm can be calculated. As may be expected, the results show that the combination from the paired events is very small compared to the total scintillation yield but of the same order as that of double strand breaks in mammalian cells. The resulted simulation showed a yield of 10<super>-2</super> dsb's/keV which is in close proximity with the theoretical result, for a 4 MeV alpha particle, of 7 x 10<super>-3</super> dsb's/keV. Both the theory and preliminary experimental investigation with a semi-infinite disc of plastic phosphor, 20 mum thick, reveals that the method is potential promising but more detailed study is required on the process for extraction of the desired signal from the practical device.
1997-06-01T00:00:00ZAlkharam, Ali SalemIt is widely agreed in radiobiological and biophysical research that the DNA is the dominant target which can lead to terminal biological damage in the form of cancer or cell death. A main objective in radiation protection is to set the limits of the possible harmful effects to the general population exposed to ionising radiation at low level (environmental level). The initial slope of the dose-response curve is found to be an appropriate parameter to achieve this objective. Bench mark data sets of the initial effects of ionising radiation on cells in vitro were formed which include both physical characterisation of the radiation and the radiobiological parameters. These data-bases include the mammalian cell end-points: cellular inactivation, chromosome dicentrics, HPRT mutations and oncogenic transformations. On the molecular scale, the databases include single-strand and double strand breaks induced in the DNA of both mammalian and non-mammalian cells. Analysis of bio-effect mechanisms of damage to mammalian cells in terms of the quality parameter 'mean free path for linear primary ionisation' for ionising radiation, strongly suggest that there is a common mechanism for the biological endpoints of dicentrics, mutations, and oncogemc transformations. A unified response is obtained for all types of heavy ions and all cells which show: a common inflection point at inter-spacing distance equivalent to lambda0 = 1.4+/- 0.5 nm, a saturation region at lambda < lambda0 and almost constant slope for lambda < lambda0. The lethal lesions are identified as dsb's in the intracellular DNA. It follows that radiation risk factors can be determined on the basis of simple ratios to the inactivation cross sections. The size of these genes are found to be in close proximity to the optimised saturation levels. The probabilities of risk with respect to inactivation, for chromosome dicentrics, oncogenic transformations, and mutations of the HPRT gene are respectively 0.18, 1.6 x 10<super>-4 </super>and 2.91 x 10<super>-5</super>. The same analysis shows that sparsely ionising radiations, which have lower effect cross-sections by an order of magnitude or more, can never reach saturation. Analysis of the molecular dsb's of DNA produced in mammalian cells by heavy ions shows a lower saturation cross-section of 0.83 mum2 which may be compared with the geometrical cross-section of 3.5 mum2. The difference is attributed to a higher packing factor. Calculations using earlier endpoint saturation cross-sections show that 4 dsb's in DNA of a human lymphocyte cell are needed to induce a chromosome dicentric, 100 dsb's in DNA of a C3H10T1/2 cell are needed to inactivate an oncogene, and 3500 dsb's in DNA of a V79 cell are needed on average to delete an HPRT mutant. The feasibility to design a new dosimetric system which would have a unified response, as described above, is considered. NE102A plastic scintillators of 20 mum thickness are found to be a potentially good prospect for detecting weak ionising radiation. By adjusting the concentration of the activator, the mean of the random distance between centres can be modified to simulate the strand-pair distribution of the DNA in mammalian cells. Thus it is possible to simulate the yield of dsb's in DNA damage as those paired centres spaced by about 1.8 nm and to distinguish them from other unwanted pairs of activated sites with different spacings. Using a 60Co-y radiation source, and starting from the knowledge of the equilibrium slowing down spectrum of electrons in plastic scintillator, the yields of photons and paired events with an inter-spacing distance of - 1.8 nm can be calculated. As may be expected, the results show that the combination from the paired events is very small compared to the total scintillation yield but of the same order as that of double strand breaks in mammalian cells. The resulted simulation showed a yield of 10<super>-2</super> dsb's/keV which is in close proximity with the theoretical result, for a 4 MeV alpha particle, of 7 x 10<super>-3</super> dsb's/keV. Both the theory and preliminary experimental investigation with a semi-infinite disc of plastic phosphor, 20 mum thick, reveals that the method is potential promising but more detailed study is required on the process for extraction of the desired signal from the practical device.Nanoscintometry : a pathway to absolute dosimetry of ionising radiations.McDougall, Ian Cameronhttps://hdl.handle.net/10023/133592019-04-01T08:53:41Z1998-10-01T00:00:00ZIt is now accepted that the deleterious effects induced by ionising radiations in mammalian cells are caused by the simultaneous breaking of both strands of the DNA helix by a single track. These effects are optimised when the mean free path of primary ionisation. lambda, matches the 2 nanometre mean chord distribution of DNA. However, there is currently no method of measuring radiation damage in terms of lambda. The aim of this project has been to design and construct a detector with a lambda response function capable of providing a measure of the absolute biological effectiveness of a radiation, independent of radiation type. Organic scintillation molecules, in the condensed phase, have been identified as being most suitable for bio-effectiveness measurements. Tissue equivalent and of comparable interaction cross-section, these nanodetectors are capable of signalling individual interactions with the emission of a scintillation photon, or scinton. Using a 20 mum scintillation film and DEP hybrid photodiode, spectra containing single and plural scinton events were recorded. These spectra reveal unique differences in the radiation quality of photon-emitting radioisotopes. A model of radiation action on scintillators in the condensed phase, analogous to the direct and indirect actions observed in intra-cellular DNA, has been developed and used to predict the characteristic yields of single and plural scinton events. The model was further developed to provide probabilities of paired' scinton events originating from fluor sites with a mean spacing of 2 nm. These critical 'paired' events are representative of double strand breaks and interpretation of these events that will yield bio-effectiveness data. Using Poisson distributions, a scintillator with optimised fluor concentration was developed for use in bio-effectiveness detectors. Loss calculations within the detector revealed an inconsistency in exponential attenuation theory, which appears to be inadequate when applied to light-guides. Consequently a new model of photon transport in light-pipes based on a Monte Carlo simulation has been developed and offers a more rigorous alternative. Calibration of the detector highlighted the need for a simple yet effective technique for photomultiplier tube (PMT) gain calibration in the laboratory. A technique using Cerenkov radiation was developed and provides good correlation with published gain figures. Although this prototype detector has not yet been fully tested, nor the associated bio-effect model fully developed to allow extraction of bio-effectiveness data from the collected spectra, preliminary results suggest this technique to be promising alternative and offers a route towards the measurement of absolute dosimetry with potential application in radiotherapy and radiation protection.
1998-10-01T00:00:00ZMcDougall, Ian CameronIt is now accepted that the deleterious effects induced by ionising radiations in mammalian cells are caused by the simultaneous breaking of both strands of the DNA helix by a single track. These effects are optimised when the mean free path of primary ionisation. lambda, matches the 2 nanometre mean chord distribution of DNA. However, there is currently no method of measuring radiation damage in terms of lambda. The aim of this project has been to design and construct a detector with a lambda response function capable of providing a measure of the absolute biological effectiveness of a radiation, independent of radiation type. Organic scintillation molecules, in the condensed phase, have been identified as being most suitable for bio-effectiveness measurements. Tissue equivalent and of comparable interaction cross-section, these nanodetectors are capable of signalling individual interactions with the emission of a scintillation photon, or scinton. Using a 20 mum scintillation film and DEP hybrid photodiode, spectra containing single and plural scinton events were recorded. These spectra reveal unique differences in the radiation quality of photon-emitting radioisotopes. A model of radiation action on scintillators in the condensed phase, analogous to the direct and indirect actions observed in intra-cellular DNA, has been developed and used to predict the characteristic yields of single and plural scinton events. The model was further developed to provide probabilities of paired' scinton events originating from fluor sites with a mean spacing of 2 nm. These critical 'paired' events are representative of double strand breaks and interpretation of these events that will yield bio-effectiveness data. Using Poisson distributions, a scintillator with optimised fluor concentration was developed for use in bio-effectiveness detectors. Loss calculations within the detector revealed an inconsistency in exponential attenuation theory, which appears to be inadequate when applied to light-guides. Consequently a new model of photon transport in light-pipes based on a Monte Carlo simulation has been developed and offers a more rigorous alternative. Calibration of the detector highlighted the need for a simple yet effective technique for photomultiplier tube (PMT) gain calibration in the laboratory. A technique using Cerenkov radiation was developed and provides good correlation with published gain figures. Although this prototype detector has not yet been fully tested, nor the associated bio-effect model fully developed to allow extraction of bio-effectiveness data from the collected spectra, preliminary results suggest this technique to be promising alternative and offers a route towards the measurement of absolute dosimetry with potential application in radiotherapy and radiation protection.Psychological factors predicting health behaviour : the response to risk factor screening for cardiovascular diseaseSimpson, Wendy M.https://hdl.handle.net/10023/133562019-04-01T08:52:33Z1996-07-01T00:00:00ZThe two main aims of this thesis were first, to predict health behaviour and, second, to apply and test the existing psychological theories in this field. The health behaviours concerned were the responses to screening for risk factors for cardiovascular disease. Three empirical studies were carried out. The first response to screening is whether one attends or not. Results showed that uptake of screening in worksite settings (N=425) (Chapter 2) could be predicted by the health beliefs derived from social cognition models. Intention to attend was the best predictor of attendance. However, differences in predictive beliefs between worksites suggested communication factors were also an issue. Subsequently, communication factors were investigated in a study of uptake in general practice (N=210) (Chapter 4) finding that the method of offering screening affected uptake significantly. The second response to screening is the impact it has on the screenee. Results found that communication factors had little effect on screening impact in that there was little difference between three methods of offering screening in terms of their subsequent impact on patients' satisfaction, knowledge, intention or behaviour change (Chapter 4). Social cognitions, however, were found to predict impact in terms of behaviour change with a sample of attenders (N=59) at a screening clinic in general practice (Chapter 3). In the latter study, perceived threat was the best predictor of behaviour change. Four social cognition models were compared against each other in the classification of attenders and non-attenders in the Worksite study (Chapter 2). Apart from Social Learning Theory the other models performed adequately, but the Theory of Reasoned Action was the most successful. More recent theories were examined in the prediction of behaviour change following screening (Chapter 3). The data supported the stage model, the Precaution Adoption Process. The internal structure of the Health Action Process Approach was questioned, but the addition of an 'action phase' in tills model showed promise.
1996-07-01T00:00:00ZSimpson, Wendy M.The two main aims of this thesis were first, to predict health behaviour and, second, to apply and test the existing psychological theories in this field. The health behaviours concerned were the responses to screening for risk factors for cardiovascular disease. Three empirical studies were carried out. The first response to screening is whether one attends or not. Results showed that uptake of screening in worksite settings (N=425) (Chapter 2) could be predicted by the health beliefs derived from social cognition models. Intention to attend was the best predictor of attendance. However, differences in predictive beliefs between worksites suggested communication factors were also an issue. Subsequently, communication factors were investigated in a study of uptake in general practice (N=210) (Chapter 4) finding that the method of offering screening affected uptake significantly. The second response to screening is the impact it has on the screenee. Results found that communication factors had little effect on screening impact in that there was little difference between three methods of offering screening in terms of their subsequent impact on patients' satisfaction, knowledge, intention or behaviour change (Chapter 4). Social cognitions, however, were found to predict impact in terms of behaviour change with a sample of attenders (N=59) at a screening clinic in general practice (Chapter 3). In the latter study, perceived threat was the best predictor of behaviour change. Four social cognition models were compared against each other in the classification of attenders and non-attenders in the Worksite study (Chapter 2). Apart from Social Learning Theory the other models performed adequately, but the Theory of Reasoned Action was the most successful. More recent theories were examined in the prediction of behaviour change following screening (Chapter 3). The data supported the stage model, the Precaution Adoption Process. The internal structure of the Health Action Process Approach was questioned, but the addition of an 'action phase' in tills model showed promise.Cost-effectiveness considerations in finding appropriate chemotherapy treatments for bacterial diseases in developing countries: The case of tuberculosis.Bethel, Lisa M.https://hdl.handle.net/10023/133452019-04-01T08:53:46Z1996-07-01T00:00:00ZInfectious bacterial diseases in developing countries represent a major health threat. Living conditions and environment decrease health status such that those in developing countries are left vulnerable to many diseases that are seldom seen in industrialised countries. Many treatments for these diseases have proven very effective, making infectious bacterial disease one of the best targets for high yield, low cost health interventions. Antibiotics remain the primary approach in treating infectious bacterial disease, yet mismanagement in their use has led to unnecessary resistance making many major diseases difficult to treat. Additionally, poor antibiotic choices for treating diseases have further contributed to unnecessary resistance. The appropriate choice for treating diseases is not always made and many diseases continue to be treated with inappropriate drugs or combinations of drugs. Many treatments are chosen on the basis of their easy availability or their small cost, when in fact other treatments could be obtained that have a more substantial impact on decreasing the incidence of a given disease. This is especially true in the treatment of tuberculosis. Tuberculosis, once thought to have been almost eradicated, has been revived by the growth of HTV. TB still claims a substantial proportion of human lives and will be responsible for 30 million deaths in this decade alone. Of particular relevance is the rising incidence of drug resistant cases of TB, which is primarily due to inappropriate antibiotic use. Although some past research has acknowledged the influence of resistance on the cost of TB treatment in developing countries, few studies have thoroughly analysed this relationship. This thesis presents a comprehensive study of the impact of drug resistance on the cost of TB treatment within the context of a cost-effectiveness analysis comparing short-course chemotherapy and the standard drug regimen in Ethiopia. In addition, the impact of HIV on TB treatment is analysed together with other factors, such as case holding, in order to assess their respective influence on the cost of treatment. Criteria for better management of tuberculosis control efforts in order to eradicate this disease and control resistance are subsequently explored. Finally, a discussion of the broader applicability of the conclusions of these studies to many developing countries is presented.
1996-07-01T00:00:00ZBethel, Lisa M.Infectious bacterial diseases in developing countries represent a major health threat. Living conditions and environment decrease health status such that those in developing countries are left vulnerable to many diseases that are seldom seen in industrialised countries. Many treatments for these diseases have proven very effective, making infectious bacterial disease one of the best targets for high yield, low cost health interventions. Antibiotics remain the primary approach in treating infectious bacterial disease, yet mismanagement in their use has led to unnecessary resistance making many major diseases difficult to treat. Additionally, poor antibiotic choices for treating diseases have further contributed to unnecessary resistance. The appropriate choice for treating diseases is not always made and many diseases continue to be treated with inappropriate drugs or combinations of drugs. Many treatments are chosen on the basis of their easy availability or their small cost, when in fact other treatments could be obtained that have a more substantial impact on decreasing the incidence of a given disease. This is especially true in the treatment of tuberculosis. Tuberculosis, once thought to have been almost eradicated, has been revived by the growth of HTV. TB still claims a substantial proportion of human lives and will be responsible for 30 million deaths in this decade alone. Of particular relevance is the rising incidence of drug resistant cases of TB, which is primarily due to inappropriate antibiotic use. Although some past research has acknowledged the influence of resistance on the cost of TB treatment in developing countries, few studies have thoroughly analysed this relationship. This thesis presents a comprehensive study of the impact of drug resistance on the cost of TB treatment within the context of a cost-effectiveness analysis comparing short-course chemotherapy and the standard drug regimen in Ethiopia. In addition, the impact of HIV on TB treatment is analysed together with other factors, such as case holding, in order to assess their respective influence on the cost of treatment. Criteria for better management of tuberculosis control efforts in order to eradicate this disease and control resistance are subsequently explored. Finally, a discussion of the broader applicability of the conclusions of these studies to many developing countries is presented.Examining QALY's : analysing the use of quality adjusted life years in the allocation of health care resourcesPetrou, Stavroshttps://hdl.handle.net/10023/133442019-04-01T08:53:16Z1992-07-01T00:00:00ZThis thesis examines the use quality adjusted life years (QALY'S) in the allocation of health care resources. It is divided into three broad sections. The first section discusses how health status measurement techniques can be used to derive the utility values incorporated into QALY'S. The second section uses one health status measurement instrument, the Rosser-Kind Classification of Illness States, to estimate the QALY'S gained by patients who have undergone hip and knee joint replacement surgery. It is shown that the Rosser-Kind Classification of Illness States is as effective in measuring the health-related quality of life of these patients as more detailed questionnaires. In addition, it is found that further research is required before any generalisations concerning the acceptability of retrospective data can be made. A third important result is that there are significant improvements in health- related quality of life following both types of surgery, with the highest Rosser- Kind rating scores achieved after the first year following knee replacement surgery and after the second year following hip replacement surgery. The third section of the thesis performs an extensive sensitivity analysis on the widely-quoted cost utility estimates for seven medical procedures, calculated by Gudex (1986). The estimates are shown to be sensitive to Gudex's conversion of health outcome data into the Rosser-Kind Classification, her assumptions concerning the survival period / life expectancy following each of the medical procedures and the selected discount rate. A more in depth analysis is then performed on the cost utility estimate for one of the seven procedures, ceftazidime treatment of cystic fibrosis. It is demonstrated that the health outcome and cost assumptions underlying the cost utility estimate for this procedure are not supported by the medical literature. Finally, the thesis raises a number of issues for discussion.
1992-07-01T00:00:00ZPetrou, StavrosThis thesis examines the use quality adjusted life years (QALY'S) in the allocation of health care resources. It is divided into three broad sections. The first section discusses how health status measurement techniques can be used to derive the utility values incorporated into QALY'S. The second section uses one health status measurement instrument, the Rosser-Kind Classification of Illness States, to estimate the QALY'S gained by patients who have undergone hip and knee joint replacement surgery. It is shown that the Rosser-Kind Classification of Illness States is as effective in measuring the health-related quality of life of these patients as more detailed questionnaires. In addition, it is found that further research is required before any generalisations concerning the acceptability of retrospective data can be made. A third important result is that there are significant improvements in health- related quality of life following both types of surgery, with the highest Rosser- Kind rating scores achieved after the first year following knee replacement surgery and after the second year following hip replacement surgery. The third section of the thesis performs an extensive sensitivity analysis on the widely-quoted cost utility estimates for seven medical procedures, calculated by Gudex (1986). The estimates are shown to be sensitive to Gudex's conversion of health outcome data into the Rosser-Kind Classification, her assumptions concerning the survival period / life expectancy following each of the medical procedures and the selected discount rate. A more in depth analysis is then performed on the cost utility estimate for one of the seven procedures, ceftazidime treatment of cystic fibrosis. It is demonstrated that the health outcome and cost assumptions underlying the cost utility estimate for this procedure are not supported by the medical literature. Finally, the thesis raises a number of issues for discussion.An analysis of the role of state, economy and civil society in the development, management and reform of the NHS 1948 - 1997Lockett, Anthony E.https://hdl.handle.net/10023/133432019-04-01T08:52:51Z1999-03-01T00:00:00ZThe NHS is the centrepiece of the UK welfare state. For fifty years it has provided the majority of health-care in the UK. However the running of the service has not been marked by a smooth operation. Repeated reforms have occurred since 1948 in attempts to increase the efficiency and effectiveness of the service. These reforms have been credited with varying degrees of success. Even the most radical reforms, initiated in 1990, have been marked by some failures - particularly in respect to the provision of services to 'at risk' groups such as the elderly, leading to criticisms of a lack of coherent policy making. The reasons that underlie the success of the NHS in the midst of failure are complicated, but one hypothesis is that the structure of the NHS does not reflect its basic functions. Those functions can be broken down into 2. First is the relief of suffering from illness; second is the support of the industrial and economic base of the UK. The existence of this pluralistic purpose implies that the management of the service requires balancing the forces of economic, state and civil society requirements for the NHS. This management is embodied in a complicated institutionalisation of care, covered in chapter 1. The empirical evidence gathered in the thesis, in chapters 2 and 3 both from literature and case studies, would indicate that at least part of the problems seen in the NHS result from a failure to balance this institutionalisation. However, the situation is made more complex as the result of this imbalance creates further increased demands from some of the elements in the management of the service. Therefore the failure to balance the interactions that surround the NHS increases the pressures on it which in turn increases the imbalance leading to a feedback loop magnifying the problem. The source and problems of this feedback are best exemplified by a case study of the most recent reforms -covered in chapters 4-11 of this thesis. This case study demonstrates that the way in which the 1990 reforms were formulated and implemented took little notice of the impact of the changes on the street level NHS managers - with the results that the reforms did not represent a coherent policy. The result of the lack of coherence is that the changes have not generated efficiency gains, and in some cases have diverted resources away from those most in need. The underlying cause of this is the predominance of non- market forces in the decision making process - i.e. the values of the purchasers and the power of the providers to influence decision making. The linkages between these features of the post reform NHS are described in chapter 12. It is likely that the only way in which the circle of problems in the NHS can be addressed is re-establishing the corporate relationship that surrounds health care. However unlike previous relationships the evidence suggests that the relationship should be established at a policy level, rather than the current trends for a local level relationship. The NHS is not unique in this aspect, as this is the pattern of change seen in many European Countries.
1999-03-01T00:00:00ZLockett, Anthony E.The NHS is the centrepiece of the UK welfare state. For fifty years it has provided the majority of health-care in the UK. However the running of the service has not been marked by a smooth operation. Repeated reforms have occurred since 1948 in attempts to increase the efficiency and effectiveness of the service. These reforms have been credited with varying degrees of success. Even the most radical reforms, initiated in 1990, have been marked by some failures - particularly in respect to the provision of services to 'at risk' groups such as the elderly, leading to criticisms of a lack of coherent policy making. The reasons that underlie the success of the NHS in the midst of failure are complicated, but one hypothesis is that the structure of the NHS does not reflect its basic functions. Those functions can be broken down into 2. First is the relief of suffering from illness; second is the support of the industrial and economic base of the UK. The existence of this pluralistic purpose implies that the management of the service requires balancing the forces of economic, state and civil society requirements for the NHS. This management is embodied in a complicated institutionalisation of care, covered in chapter 1. The empirical evidence gathered in the thesis, in chapters 2 and 3 both from literature and case studies, would indicate that at least part of the problems seen in the NHS result from a failure to balance this institutionalisation. However, the situation is made more complex as the result of this imbalance creates further increased demands from some of the elements in the management of the service. Therefore the failure to balance the interactions that surround the NHS increases the pressures on it which in turn increases the imbalance leading to a feedback loop magnifying the problem. The source and problems of this feedback are best exemplified by a case study of the most recent reforms -covered in chapters 4-11 of this thesis. This case study demonstrates that the way in which the 1990 reforms were formulated and implemented took little notice of the impact of the changes on the street level NHS managers - with the results that the reforms did not represent a coherent policy. The result of the lack of coherence is that the changes have not generated efficiency gains, and in some cases have diverted resources away from those most in need. The underlying cause of this is the predominance of non- market forces in the decision making process - i.e. the values of the purchasers and the power of the providers to influence decision making. The linkages between these features of the post reform NHS are described in chapter 12. It is likely that the only way in which the circle of problems in the NHS can be addressed is re-establishing the corporate relationship that surrounds health care. However unlike previous relationships the evidence suggests that the relationship should be established at a policy level, rather than the current trends for a local level relationship. The NHS is not unique in this aspect, as this is the pattern of change seen in many European Countries.Dosimetry for absolute biological effectiveness of ionising radiationsKadiri, Lawal Abdulhttps://hdl.handle.net/10023/133362019-04-01T08:52:53Z1991-07-01T00:00:00ZIt was shown that the conventional radiation dosimetric system which is based on RBE and LET is incapable of determining the likely consequences of ionising radiation exposure. Analyses of data on the induction of the chromosome aberrations, mutations and transformation in mammalian cells by radiations of different types and energies has indicated that (a) the induction of double strand breaks (dsb) in the DNA is their common critical lesion, (b) Fast ions and neutrons radiations are by order of magnitude more damaging than photons and electrons of equal mean free path, (c) Damage is through intra track action of the charged particles. A new system of radiation dosimetry, which does not require a radiation quality parameter, was proposed. It was based on the observation that for each of the biological endpoints considered an Absolute Biological Effectiveness (ABE) for damage by the charged particles can be defined as the product of the charged particle fluence and the saturation effect cross section, scaled with the efficiency (e) of damage by radiation of mean free path (lambda). e is given by 1-exp-(lambda0/lambda), where lambda0), about 1.8nm, is the mean inter-strand distance of the DNA. The physical requirements for its instrumentation, basically the emulation and quantification of the induction of dsb in the DNA, were defined. The feasibility for its realisation using detectors based on gas ionisation, superconductivity, secondary electron emission, and semiconductivity was assessed. Ultrathin films of rectified, organic semiconductors appeared to have the best potential, but such materials are not yet available in the physically characterised form as may be required for detector construction; investigations were made with available films of plastic scintillators. Experimental investigations have shown that by using coincidence techniques, plastic scintillator films can be used as a single volume 'microdosimeter', that is as counters of single strand breaks. Its use as a single volume 'nanodosimeter' is handicapped by light losses in the detector assembly which reduces the detector's sensitivity, efficiency and resolution. Semi-empirical analysis showed that the production of light from a phosphor differs fundamentally from the induction of biological damage. It was inferred that the plastic scintillators are unsuitable for instrumentation of the proposed system of dosimetry. Suggestions for future investigations were made.
1991-07-01T00:00:00ZKadiri, Lawal AbdulIt was shown that the conventional radiation dosimetric system which is based on RBE and LET is incapable of determining the likely consequences of ionising radiation exposure. Analyses of data on the induction of the chromosome aberrations, mutations and transformation in mammalian cells by radiations of different types and energies has indicated that (a) the induction of double strand breaks (dsb) in the DNA is their common critical lesion, (b) Fast ions and neutrons radiations are by order of magnitude more damaging than photons and electrons of equal mean free path, (c) Damage is through intra track action of the charged particles. A new system of radiation dosimetry, which does not require a radiation quality parameter, was proposed. It was based on the observation that for each of the biological endpoints considered an Absolute Biological Effectiveness (ABE) for damage by the charged particles can be defined as the product of the charged particle fluence and the saturation effect cross section, scaled with the efficiency (e) of damage by radiation of mean free path (lambda). e is given by 1-exp-(lambda0/lambda), where lambda0), about 1.8nm, is the mean inter-strand distance of the DNA. The physical requirements for its instrumentation, basically the emulation and quantification of the induction of dsb in the DNA, were defined. The feasibility for its realisation using detectors based on gas ionisation, superconductivity, secondary electron emission, and semiconductivity was assessed. Ultrathin films of rectified, organic semiconductors appeared to have the best potential, but such materials are not yet available in the physically characterised form as may be required for detector construction; investigations were made with available films of plastic scintillators. Experimental investigations have shown that by using coincidence techniques, plastic scintillator films can be used as a single volume 'microdosimeter', that is as counters of single strand breaks. Its use as a single volume 'nanodosimeter' is handicapped by light losses in the detector assembly which reduces the detector's sensitivity, efficiency and resolution. Semi-empirical analysis showed that the production of light from a phosphor differs fundamentally from the induction of biological damage. It was inferred that the plastic scintillators are unsuitable for instrumentation of the proposed system of dosimetry. Suggestions for future investigations were made.Medieval English medical practice and the law : an analysis of casesPorter, Elizabeth-Annehttps://hdl.handle.net/10023/133352019-04-01T08:52:38Z1998-04-01T00:00:00ZThis thesis is an exploration of the relationship between medieval medicine and the law from the thirteenth to the early sixteenth-century. Selected records of litigation between practitioners and their patients, particularly malpractice cases, have been used to illustrate not only the interaction of medical men with the law, but also to provide information on the practice of medicine, its practitioners and those who came to it for succour. A database of forty-six selected cases underpins this study. Chapter one seeks to establish the context of the medieval medical profession. It reveals it to be a wide open marketplace in which several competitive factions operated, from the unlicensed leech to the university-educated physician; from the lowly barber to the guild-licensed surgeon. The medieval patient therefore had a wide choice of practitioners and a similarly wide range of expectancy. Chapter two examines contemporary legal treatises and compilations in order to establish the theoretical legal context to medical and surgical practice. The responsibilities and culpabilities of practitioners are examined, and their role as expert witness is discussed. Chapter three looks at the legal forums and procedures in which the selected cases were heard in practice. The procedures used, such as writs, and legal concepts, such as those of malpractice and trespass are illustrated by reference to specific cases in this study. Also discussed is private arbitration as an alternative to court litigation in the settlement of disputes between patient and practitioner. Lastly the forty-six cases in the database are examined to provide information on actual medical practice. Areas of discussion include contractual relationships between practitioners and their patients, demographic information and the nature of both disease and treatment encountered in the cases of the database. Thereby a vivid insight is provided into the interaction of the medical practitioner and the law.
1998-04-01T00:00:00ZPorter, Elizabeth-AnneThis thesis is an exploration of the relationship between medieval medicine and the law from the thirteenth to the early sixteenth-century. Selected records of litigation between practitioners and their patients, particularly malpractice cases, have been used to illustrate not only the interaction of medical men with the law, but also to provide information on the practice of medicine, its practitioners and those who came to it for succour. A database of forty-six selected cases underpins this study. Chapter one seeks to establish the context of the medieval medical profession. It reveals it to be a wide open marketplace in which several competitive factions operated, from the unlicensed leech to the university-educated physician; from the lowly barber to the guild-licensed surgeon. The medieval patient therefore had a wide choice of practitioners and a similarly wide range of expectancy. Chapter two examines contemporary legal treatises and compilations in order to establish the theoretical legal context to medical and surgical practice. The responsibilities and culpabilities of practitioners are examined, and their role as expert witness is discussed. Chapter three looks at the legal forums and procedures in which the selected cases were heard in practice. The procedures used, such as writs, and legal concepts, such as those of malpractice and trespass are illustrated by reference to specific cases in this study. Also discussed is private arbitration as an alternative to court litigation in the settlement of disputes between patient and practitioner. Lastly the forty-six cases in the database are examined to provide information on actual medical practice. Areas of discussion include contractual relationships between practitioners and their patients, demographic information and the nature of both disease and treatment encountered in the cases of the database. Thereby a vivid insight is provided into the interaction of the medical practitioner and the law.Classification of burns : a history of development; with comments for today and thoughts for the futureWallace, Alexander Burnshttps://hdl.handle.net/10023/129932019-04-01T08:53:12Z1973-01-01T00:00:00Z"Burn injuries have afflicted man from the times of primitive civilisation and universally are acknowledged as all too frequent. Most occur in the home to the younger and older age groups and so measured in terms of human sorrow are all the more personal and tragic. Undoubtedly thermal trauma is a major world health issue and in a country like India has become a greater hazard to wellbeing than leprosy. The treatment of burning injuries has received much attention over the centuries yet results, especially in the more extensive forms, remain uncertain. Traumata from sharp and blunt objects lend themselves to accurate classification and to appropriate measures, but with burns no generally acceptable form of classification has been up to now capable of relation to methods of treatment. What are the difficulties? The aim of this thesis is to trace the evolution and significance of the various classifications of thermal injury and to submit a final summary of the attitude of the present and possible procedures for the future." -- from the Introduction.
1973-01-01T00:00:00ZWallace, Alexander Burns"Burn injuries have afflicted man from the times of primitive civilisation and universally are acknowledged as all too frequent. Most occur in the home to the younger and older age groups and so measured in terms of human sorrow are all the more personal and tragic. Undoubtedly thermal trauma is a major world health issue and in a country like India has become a greater hazard to wellbeing than leprosy. The treatment of burning injuries has received much attention over the centuries yet results, especially in the more extensive forms, remain uncertain. Traumata from sharp and blunt objects lend themselves to accurate classification and to appropriate measures, but with burns no generally acceptable form of classification has been up to now capable of relation to methods of treatment. What are the difficulties? The aim of this thesis is to trace the evolution and significance of the various classifications of thermal injury and to submit a final summary of the attitude of the present and possible procedures for the future." -- from the Introduction.Was King John of England bipolar? : a medical history using mathematical modellingGillespie, Janet Patriciahttps://hdl.handle.net/10023/121952019-04-01T08:53:07Z2017-06-23T00:00:00ZBACKGROUND - Bipolar disorder has been postulated as an explanation for King John's inconsistencies of leadership and vagaries of character. Changes in activity, matching those in mood, are core features of the condition.
METHOD - A measure of King John's activity was derived from his travelling itinerary. Change Point Analysis (CPA) was used to detect significant changes in that travelling activity and from them, to identify clinically compliant, high and low, activity time periods. The results were tested against an alternative mathematical model (Bollinger Bands™), three alternative parameters and two comparator itineraries (familial & non-familial). Using primary historical sources and published analyses, bipolar symptoms were identified and their temporal relationship to the ICD-10 compliant CPA periods evaluated. The influence of circumstances was also evaluated using primary sources and a representative sequential sample (1200-1204).
RESULTS - CPA identified 83 periods of changed travelling activity. These changes were mathematically independent of the availability of the historical sources that underpin the itinerary. From these, 37 high and 22 low periods complied with current diagnostic guidelines and demonstrated descriptive and statistical similarities to those found in the bipolar literature. Analyses using alternative mathematical modelling and different parameters showed similar changes; analyses of comparator itineraries showed a possible familial trait. Of the 17 bipolar symptoms identified, all were found in CPA periods of appropriate polarity. Of the 23 sequential periods, 10 showed evidence of behaviour that was difficult to attribute to circumstances.
CONCLUSIONS & OUTCOMES - The pattern of changes in King John's activity are highly suggestive of bipolar disorder with primary historical sources describing synchronous bipolar behaviour. This may alter our understanding both of King John and of Magna Carta. Change Point Analysis merits greater consideration when analysing time based data, as does the use of activity as an objective marker of human behaviour.
2017-06-23T00:00:00ZGillespie, Janet PatriciaBACKGROUND - Bipolar disorder has been postulated as an explanation for King John's inconsistencies of leadership and vagaries of character. Changes in activity, matching those in mood, are core features of the condition.
METHOD - A measure of King John's activity was derived from his travelling itinerary. Change Point Analysis (CPA) was used to detect significant changes in that travelling activity and from them, to identify clinically compliant, high and low, activity time periods. The results were tested against an alternative mathematical model (Bollinger Bands™), three alternative parameters and two comparator itineraries (familial & non-familial). Using primary historical sources and published analyses, bipolar symptoms were identified and their temporal relationship to the ICD-10 compliant CPA periods evaluated. The influence of circumstances was also evaluated using primary sources and a representative sequential sample (1200-1204).
RESULTS - CPA identified 83 periods of changed travelling activity. These changes were mathematically independent of the availability of the historical sources that underpin the itinerary. From these, 37 high and 22 low periods complied with current diagnostic guidelines and demonstrated descriptive and statistical similarities to those found in the bipolar literature. Analyses using alternative mathematical modelling and different parameters showed similar changes; analyses of comparator itineraries showed a possible familial trait. Of the 17 bipolar symptoms identified, all were found in CPA periods of appropriate polarity. Of the 23 sequential periods, 10 showed evidence of behaviour that was difficult to attribute to circumstances.
CONCLUSIONS & OUTCOMES - The pattern of changes in King John's activity are highly suggestive of bipolar disorder with primary historical sources describing synchronous bipolar behaviour. This may alter our understanding both of King John and of Magna Carta. Change Point Analysis merits greater consideration when analysing time based data, as does the use of activity as an objective marker of human behaviour.The health and socioeconomic impact of traffic-related air pollution in ScotlandHyland, Jackiehttps://hdl.handle.net/10023/117342019-11-05T15:53:48Z2017-08-29T00:00:00ZTraffic-related air pollution harms health, so whilst it would be advantageous to improve air quality, the socioeconomic impact of air pollution mitigation in Scotland is not fully understood. Evidence from research literature, current regulatory and policy directives and a socioeconomic analysis are required to assess the true health impact. This thesis presents the first health and socioeconomic analysis of traffic-related air pollution and health for Scotland.
A critique of the literature was undertaken to determine the evidence base and the strength of evidence in terms of association and causation, between air pollution and ill health. The evidence was subsequently applied in epidemiological studies of Scottish residents, to assess the actual impact on health in Scotland. The perception of barriers and incentives for change were investigated to understand behavioural influences. Recent policy development in Scotland was reviewed, and a socioeconomic analysis of a proposed air pollution strategy in Scotland, was undertaken.
The evidence from 30 cohort studies and nine literature reviews demonstrated a link between poor air quality, mortality and respiratory ill health, but the results for other health conditions were inconsistent. The links were associative rather than causal and therefore might be attributable to other factors other than air pollution. Furthermore, epidemiological studies on Scottish populations did not show health effects from traffic-related air pollution.
The socioeconomic analysis suggested that an initial investment of between £27m and £44m to introduce Low Emission Zones (LEZ), and an effective active travel programme, might result in a saving of £38m in terms of Years of Life Lost (YLL) and reduction in sickness absence. It is unlikely that the Clean Air For Scotland Strategy will deliver improved air quality and health without substantial investment, better alignment of planning, and a greater public engagement to support public and active transport options.
2017-08-29T00:00:00ZHyland, JackieTraffic-related air pollution harms health, so whilst it would be advantageous to improve air quality, the socioeconomic impact of air pollution mitigation in Scotland is not fully understood. Evidence from research literature, current regulatory and policy directives and a socioeconomic analysis are required to assess the true health impact. This thesis presents the first health and socioeconomic analysis of traffic-related air pollution and health for Scotland.
A critique of the literature was undertaken to determine the evidence base and the strength of evidence in terms of association and causation, between air pollution and ill health. The evidence was subsequently applied in epidemiological studies of Scottish residents, to assess the actual impact on health in Scotland. The perception of barriers and incentives for change were investigated to understand behavioural influences. Recent policy development in Scotland was reviewed, and a socioeconomic analysis of a proposed air pollution strategy in Scotland, was undertaken.
The evidence from 30 cohort studies and nine literature reviews demonstrated a link between poor air quality, mortality and respiratory ill health, but the results for other health conditions were inconsistent. The links were associative rather than causal and therefore might be attributable to other factors other than air pollution. Furthermore, epidemiological studies on Scottish populations did not show health effects from traffic-related air pollution.
The socioeconomic analysis suggested that an initial investment of between £27m and £44m to introduce Low Emission Zones (LEZ), and an effective active travel programme, might result in a saving of £38m in terms of Years of Life Lost (YLL) and reduction in sickness absence. It is unlikely that the Clean Air For Scotland Strategy will deliver improved air quality and health without substantial investment, better alignment of planning, and a greater public engagement to support public and active transport options.Performing diabetes : balancing between 'patients' and 'carers', bodies and pumps, Scotland and beyondScheldeman, Griethttps://hdl.handle.net/10023/110852019-04-01T08:53:10Z2006-01-01T00:00:00ZThis study is about young people (age 11-16) with diabetes. Based on fieldwork in a
paediatric diabetes centre in Scotland, it describes the ways diabetes is lived and done by young people, their health carers and insulin pumps. This enactment is contrasted with other ways of doing diabetes, as observed on short fieldwork trips to paediatric centres in Brussels, Gothenburg and Boston.
I explore the dynamics of diabetes care on two levels. I consider the interaction between health carers and patients. Comparative data from various paediatric centres make apparent how culturally and socially informed approaches towards adolescence, health and illness shape both care practices and patients' experiences, resulting in different medical outcomes. Concretely in the Scottish centre, a non-hierarchical holistic care approach by health carers emphasizing quality of life over health, informs the young people's perspective on diabetes. Being a free adolescent takes priority over managing diabetes, with the results of ill health and possible future complications.
The existing dynamics in this care framework change as a third actor enters the scene: the insulin pump, a pager-sized technological device continuously attached to the body. I explore the balancing act between young people and their pumps. As the adolescents actively engage with their pumps not to search for better health but rather to pursue a better quality of life, the guiding question becomes: how can a technological device for insulin injection double as a tool towards a desired identity and a different illness?
This work then, can be read as a concrete case study of how a uniform technological
device is embedded and used in a specific cultural and social context. It can also be read as an argument for a re-orientation of paediatric diabetes care in the Scottish centre: care centred on collaboration and inclusion rather than focused on merely containing underlying conflict (between adults and adolescents, diabetes and life, health and quality of life). Centres in Brussels, Gothenburg and Boston, and the insulin pump concretely, show how collaboration can lead to good health and quality of life. To leave us to wonder: is 'doing diabetes differently' synonymous with 'doing a
different diabetes'?
2006-01-01T00:00:00ZScheldeman, GrietThis study is about young people (age 11-16) with diabetes. Based on fieldwork in a
paediatric diabetes centre in Scotland, it describes the ways diabetes is lived and done by young people, their health carers and insulin pumps. This enactment is contrasted with other ways of doing diabetes, as observed on short fieldwork trips to paediatric centres in Brussels, Gothenburg and Boston.
I explore the dynamics of diabetes care on two levels. I consider the interaction between health carers and patients. Comparative data from various paediatric centres make apparent how culturally and socially informed approaches towards adolescence, health and illness shape both care practices and patients' experiences, resulting in different medical outcomes. Concretely in the Scottish centre, a non-hierarchical holistic care approach by health carers emphasizing quality of life over health, informs the young people's perspective on diabetes. Being a free adolescent takes priority over managing diabetes, with the results of ill health and possible future complications.
The existing dynamics in this care framework change as a third actor enters the scene: the insulin pump, a pager-sized technological device continuously attached to the body. I explore the balancing act between young people and their pumps. As the adolescents actively engage with their pumps not to search for better health but rather to pursue a better quality of life, the guiding question becomes: how can a technological device for insulin injection double as a tool towards a desired identity and a different illness?
This work then, can be read as a concrete case study of how a uniform technological
device is embedded and used in a specific cultural and social context. It can also be read as an argument for a re-orientation of paediatric diabetes care in the Scottish centre: care centred on collaboration and inclusion rather than focused on merely containing underlying conflict (between adults and adolescents, diabetes and life, health and quality of life). Centres in Brussels, Gothenburg and Boston, and the insulin pump concretely, show how collaboration can lead to good health and quality of life. To leave us to wonder: is 'doing diabetes differently' synonymous with 'doing a
different diabetes'?Assessment of noise effects at work placeAl-Sharifi, Faisal A.https://hdl.handle.net/10023/109282019-04-01T08:52:50Z1996-01-01T00:00:00ZNoise is considered to be a physical form of environmental pollution which can
influence the health of exposed persons. Excessive exposure to noise can interfere
with performance at work and with the ability to relax or sleep. Also it may impair
hearing and it can evoke other physiological and pathological symptoms to the
detriment of health. The sources of noise may be local or general. Industrial
processes are an important source of indoor or localised noise. Persons exposed to
noise as a consequence of their employment are legally protected to some extent by
European Directives and National Regulations which limit the maximum permissible
noise levels to 85-90dB. A research project was launched with the full co-operation
of the Don and Low Group of Companies, Forfar and Perth, Scotland.
Study indicates that the proportion of employees who have noise-induced hearing
loss is higher amongst those who work in higher than 85dB, (e.g. Group 1 <85dB-11%;
Group 2 85<90dB-44%; Group 3 90<95dB-44%; Group 4≥95dB-39% = 138% in total). In all groups social and economic status, sex, age and average number of years' service are almost identical.
In general, the study indicates a higher number of employees suffered from ear
problems between groups exposed to 85dB and more, (e.g. perforated eardrum, noise
tinnitus, vertigo, wax in ears).
The danger of noise has been studied in detail regarding the general health of
employees as follows:
1. Sleep disturbance
It appeared that most of the cases who suffered from sleep disturbance were
found amongst employees exposed to greater than 85dB, averaging about 33%.
On the other hand, only 8% of the employees in category <85dB complained
of sleep disturbance.
2. Blood Pressure
According to job categories 10% of employees had heart problems in job
category higher than 85dB, but only one case reported heart problems in job
categories less than 85dB.
3. Stress
Smoking was one of the subjects studied in detail in this project and the results
were significant. An average of 40% of employees were smokers among groups
exposed to higher than 85dB compared to 10% of smokers among employees
exposed to less than 85dB.
Industrial accidents occur at a higher rate among employees who worked in noisy
environments (~85dB) with regard to reported or unreported accidents.
From the result of the research, industrial noise should be studied in a more
comprehensive way to measure all effects of noise regarding employees health by using the statistical data and always noise should be controlled at source.
Industrial noise is still a major danger to employees. From the results in this study it
appears there is a need for more co-operation between employer and employee and
not just depend on the health and safety regulations and try to solve the problem.
1996-01-01T00:00:00ZAl-Sharifi, Faisal A.Noise is considered to be a physical form of environmental pollution which can
influence the health of exposed persons. Excessive exposure to noise can interfere
with performance at work and with the ability to relax or sleep. Also it may impair
hearing and it can evoke other physiological and pathological symptoms to the
detriment of health. The sources of noise may be local or general. Industrial
processes are an important source of indoor or localised noise. Persons exposed to
noise as a consequence of their employment are legally protected to some extent by
European Directives and National Regulations which limit the maximum permissible
noise levels to 85-90dB. A research project was launched with the full co-operation
of the Don and Low Group of Companies, Forfar and Perth, Scotland.
Study indicates that the proportion of employees who have noise-induced hearing
loss is higher amongst those who work in higher than 85dB, (e.g. Group 1 <85dB-11%;
Group 2 85<90dB-44%; Group 3 90<95dB-44%; Group 4≥95dB-39% = 138% in total). In all groups social and economic status, sex, age and average number of years' service are almost identical.
In general, the study indicates a higher number of employees suffered from ear
problems between groups exposed to 85dB and more, (e.g. perforated eardrum, noise
tinnitus, vertigo, wax in ears).
The danger of noise has been studied in detail regarding the general health of
employees as follows:
1. Sleep disturbance
It appeared that most of the cases who suffered from sleep disturbance were
found amongst employees exposed to greater than 85dB, averaging about 33%.
On the other hand, only 8% of the employees in category <85dB complained
of sleep disturbance.
2. Blood Pressure
According to job categories 10% of employees had heart problems in job
category higher than 85dB, but only one case reported heart problems in job
categories less than 85dB.
3. Stress
Smoking was one of the subjects studied in detail in this project and the results
were significant. An average of 40% of employees were smokers among groups
exposed to higher than 85dB compared to 10% of smokers among employees
exposed to less than 85dB.
Industrial accidents occur at a higher rate among employees who worked in noisy
environments (~85dB) with regard to reported or unreported accidents.
From the result of the research, industrial noise should be studied in a more
comprehensive way to measure all effects of noise regarding employees health by using the statistical data and always noise should be controlled at source.
Industrial noise is still a major danger to employees. From the results in this study it
appears there is a need for more co-operation between employer and employee and
not just depend on the health and safety regulations and try to solve the problem.Role of zinc in dendritic cell activation and the regulation of complement protein interactionsWiatrek, Dagmara Martahttps://hdl.handle.net/10023/108132019-06-13T02:00:21Z2017-06-23T00:00:00ZThe importance of zinc in immune system is complex and recognised mostly by the effects of zinc deficiency which affects both innate and adaptive immunity. The results presented here provided insight into the complex role of zinc in immunity through examination of the roles of zinc in dendritic cell activation and regulation of complement protein interactions. Little is
known about the mechanism by which zinc affects immune cell function. Here we show that Toll-like receptor 4 signalling upon lipopolysaccharide (LPS) binding, alters the expression of zinc transporters, to maintain the stable intracellular free zinc. This indicates the importance of zinc on every level of dendritic cells (DCs) maturation, beginning with antigen recognition, through
antigen processing and cell migration to the lymphatic organs, to finally antigen presentation to T-cells. Hydroxyapatite along with LPS can trigger DCs maturation. Following this finding we presented a global picture of proteomic changes that occur in maturing DCs, which was characterised by reduced expression of proteins that drive cellular processes including metabolism and protein translation. Proteomic results may also change the current understanding of antigen presentation by DCs, implicating major histocompatibility complex (MHC) class I in “delayed” antigen presentation. Zinc is also crucial in innate immunity as it inhibits the interaction of complement proteins C1q, Factor H and C3 with histidine rich glycoprotein (HRG). The results suggest for the first time, that binding of complement proteins to HRG is not solely dependent on the N-terminus. Also the role of zinc in the early onset of diseases related to tissue calcification was examined, showing its enhancing effect on HRG binding to hydroxyapatite.
2017-06-23T00:00:00ZWiatrek, Dagmara MartaThe importance of zinc in immune system is complex and recognised mostly by the effects of zinc deficiency which affects both innate and adaptive immunity. The results presented here provided insight into the complex role of zinc in immunity through examination of the roles of zinc in dendritic cell activation and regulation of complement protein interactions. Little is
known about the mechanism by which zinc affects immune cell function. Here we show that Toll-like receptor 4 signalling upon lipopolysaccharide (LPS) binding, alters the expression of zinc transporters, to maintain the stable intracellular free zinc. This indicates the importance of zinc on every level of dendritic cells (DCs) maturation, beginning with antigen recognition, through
antigen processing and cell migration to the lymphatic organs, to finally antigen presentation to T-cells. Hydroxyapatite along with LPS can trigger DCs maturation. Following this finding we presented a global picture of proteomic changes that occur in maturing DCs, which was characterised by reduced expression of proteins that drive cellular processes including metabolism and protein translation. Proteomic results may also change the current understanding of antigen presentation by DCs, implicating major histocompatibility complex (MHC) class I in “delayed” antigen presentation. Zinc is also crucial in innate immunity as it inhibits the interaction of complement proteins C1q, Factor H and C3 with histidine rich glycoprotein (HRG). The results suggest for the first time, that binding of complement proteins to HRG is not solely dependent on the N-terminus. Also the role of zinc in the early onset of diseases related to tissue calcification was examined, showing its enhancing effect on HRG binding to hydroxyapatite.Radiation carcinogenesis and delayed lethal damage in a human thyroid epithelial cell lineMercer, Johnhttps://hdl.handle.net/10023/96132019-04-01T08:52:53Z1999-01-01T00:00:00ZThe human thyroid epithelial cell HTori-3 has been transformed with doses of either
chronic and acute x-rays or strontium beta particles. Models of the past have relied
upon animal cell systems to mimic in vitro carcinogenesis. The HTori-3 system
hoped to overcome the limitations associated with these types of models by using a
human thyroid cell line immortalised with the SV40 virus.
HTori-3 human thyroid epithelial cells were irradiated in vitro, passaged and then
transplanted into nude mice. Tumours that grew over a 2-6 month period were
excised and re-established in culture. Samples were stored and all tumours were
taken for histological examination. Chromosome spreads confirmed the human
nature of all tumours.
Following exposure to acute x-rays in the range of 0.25-2.0 Gy 13 tumours were
observed in 25 recipients. Following 0.25-2.0 Gy of chronic x-rays 10 tumours from
25 recipients were observed. From a single 2 Gy exposure of strontium beta
particles 3 primary tumours from 5 recipients were observed. The largest of these
was re-transplanted in nude mice resulting in 100% incidence. All tumours were
classified as undifferentiated anaplastic carcinomas. A small number of tumours
were observed in the control cell lines, these may be the result of a general
instability found with the partial transformed parental cell line.
All 2Gy tumours and those previously established from this laboratory after alpha or
gamma radiation were used to test for the presence of the delayed lethal death
phenotype. A number of cell and molecular endpoints were used. These included
plating efficiency, cell adherence, micronucleus formation and p53 status. In all
incidences, the reproductive viability of irradiated cells was below that of non-
irradiated cells at up to 4 weeks post-irradiation.
The HTori-3 cell line and the techniques used to study the delayed effects of
radiation may be applicable to other cell systems and may be a useful model to study
the long-term effects of radiation induced genomic instability.
1999-01-01T00:00:00ZMercer, JohnThe human thyroid epithelial cell HTori-3 has been transformed with doses of either
chronic and acute x-rays or strontium beta particles. Models of the past have relied
upon animal cell systems to mimic in vitro carcinogenesis. The HTori-3 system
hoped to overcome the limitations associated with these types of models by using a
human thyroid cell line immortalised with the SV40 virus.
HTori-3 human thyroid epithelial cells were irradiated in vitro, passaged and then
transplanted into nude mice. Tumours that grew over a 2-6 month period were
excised and re-established in culture. Samples were stored and all tumours were
taken for histological examination. Chromosome spreads confirmed the human
nature of all tumours.
Following exposure to acute x-rays in the range of 0.25-2.0 Gy 13 tumours were
observed in 25 recipients. Following 0.25-2.0 Gy of chronic x-rays 10 tumours from
25 recipients were observed. From a single 2 Gy exposure of strontium beta
particles 3 primary tumours from 5 recipients were observed. The largest of these
was re-transplanted in nude mice resulting in 100% incidence. All tumours were
classified as undifferentiated anaplastic carcinomas. A small number of tumours
were observed in the control cell lines, these may be the result of a general
instability found with the partial transformed parental cell line.
All 2Gy tumours and those previously established from this laboratory after alpha or
gamma radiation were used to test for the presence of the delayed lethal death
phenotype. A number of cell and molecular endpoints were used. These included
plating efficiency, cell adherence, micronucleus formation and p53 status. In all
incidences, the reproductive viability of irradiated cells was below that of non-
irradiated cells at up to 4 weeks post-irradiation.
The HTori-3 cell line and the techniques used to study the delayed effects of
radiation may be applicable to other cell systems and may be a useful model to study
the long-term effects of radiation induced genomic instability.Men with cancer : psychosocial issues, health behaviours, coping and help seekingDale, Hannahhttps://hdl.handle.net/10023/89832019-04-01T08:52:39Z2016-06-24T00:00:00ZBackground: A range of factors contribute to men with cancer having worse mortality and morbidity rates than women. The research specifically focused on psychosocial issues and health behaviours in men with cancer, and factors affecting help seeking behaviour.
Methods: A mixed-methods study recruited adult men with cancer in the East of Scotland. The quantitative cross-sectional study explored psychosocial issues, health behaviours, and desire for support. Data from the Scottish Longitudinal Study were accessed to check sample representativeness. The qualitative study built on the preliminary findings of the quantitative study and used semi-structured interviews to explore factors affecting men’s access to support. Inductive thematic analysis was undertaken.
Results: 127 men with cancer completed the questionnaire. Being separated or divorced, younger and living in a high deprivation area was associated with poor psychosocial outcomes and some lifestyle behaviours. Social support was also influential. Twenty participants were interviewed. Appraisal of, and coping with, cancer in addition to biopsychosocial antecedents, the role of masculinity, and service contexts impacted on help seeking. The findings support a modified model of the transactional model of stress and coping relevant to men with cancer, which is new and original since it specifically incorporates the role of masculinity, highlights feedback from coping to appraisal, and recognises important service context factors that impact men’s service access choices.
Discussion: Legitimisation of help seeking and the use of emotion-focused coping styles were needed by some men, particularly where ideas about masculinity played a strong role in men’s appraisal of, and coping with cancer. Implications for practice and policy relate to the survivorship agenda given the ongoing support men with cancer may need. Related to this, there is a need to carefully tailor and advertise services to men, and for health professionals to help legitimise the use of certain coping strategies and services.
2016-06-24T00:00:00ZDale, HannahBackground: A range of factors contribute to men with cancer having worse mortality and morbidity rates than women. The research specifically focused on psychosocial issues and health behaviours in men with cancer, and factors affecting help seeking behaviour.
Methods: A mixed-methods study recruited adult men with cancer in the East of Scotland. The quantitative cross-sectional study explored psychosocial issues, health behaviours, and desire for support. Data from the Scottish Longitudinal Study were accessed to check sample representativeness. The qualitative study built on the preliminary findings of the quantitative study and used semi-structured interviews to explore factors affecting men’s access to support. Inductive thematic analysis was undertaken.
Results: 127 men with cancer completed the questionnaire. Being separated or divorced, younger and living in a high deprivation area was associated with poor psychosocial outcomes and some lifestyle behaviours. Social support was also influential. Twenty participants were interviewed. Appraisal of, and coping with, cancer in addition to biopsychosocial antecedents, the role of masculinity, and service contexts impacted on help seeking. The findings support a modified model of the transactional model of stress and coping relevant to men with cancer, which is new and original since it specifically incorporates the role of masculinity, highlights feedback from coping to appraisal, and recognises important service context factors that impact men’s service access choices.
Discussion: Legitimisation of help seeking and the use of emotion-focused coping styles were needed by some men, particularly where ideas about masculinity played a strong role in men’s appraisal of, and coping with cancer. Implications for practice and policy relate to the survivorship agenda given the ongoing support men with cancer may need. Related to this, there is a need to carefully tailor and advertise services to men, and for health professionals to help legitimise the use of certain coping strategies and services.The nature, measurement and management of student nurse stress, distress and copingJones, Martyn C.https://hdl.handle.net/10023/72792019-04-01T08:53:13Z1998-01-01T00:00:00ZFollowing a review of the stress, distress and coping reported by student health professionals and students in higher education, see Chapters 2 and 3, the hypothesis that a problem existed with distress early in training was confirmed by screening two cohorts of first year student nurses, see Chapter 4. Some 50.5% of students, in Cohort one (N=109, Week 40) and 67.9% of students in Cohort two (N=111, Week 24) suffered significant levels of affective distress. All students were enrolled on the newly implemented 1992 scheme of nurse education in Tayside. The underlying dimensions of situational sources reported by student nurse stress were clarified with the development of the Student Nurse Stress Index, see Chapter 5. A reliable 22 variable solution with oblique structure and non-orthogonal factors of "academic load", "clinical sources", "intet/ace worries", "personal problems" was obtained. This measure showed cross sample factor congruence, good internal reliabilities, and concurrent and discriminant validity across a range of reporting conditions. A stress reduction/management intervention set at individual and interface levels, designed to reduce levels of student nurse distress revealed by the earlier screening study, was implemented during a second series of hospital placements, see Chapter 6. A randomised controlled trial revealed the success of this programme in reducing affective distress in 73 student nurses shown to have experienced significant levels of distress earlier in training. A series of significant treatment x time interactions were found with a range of context-free measures of affective distress, e.g. General Health Questionnaire-30 (Goldberg, 1972), State and Trait Anxiety Inventory (Speilberger, et aI., 1983), Beck Depression Inventory (Beck, et aI., 1987), with situational sources of stress (Beck & Srivastava, 1991), and Domestic Satisfaction (Derogatis, 1980). Similar treatment x time interactions were found with Direct Coping (Parkes, 1984), and Relaxation Potential (Derogatis, 1980). Adaptive changes were confmed to the experimental group alone. In addition, State Anxiety on the morning of an important exam was lower for students receiving stress management (Treatment X= 45.88, Control X =59.09). The intervention had no detectable effect on organisational variables of sickness, absence and examination performance. However, logistic regression and hierarchical multiple regression analysis showed that initial distress at screen did not predict pre or post-treatment changes in sickness or absence, or subsequent examination performance. Stress management delivered in groups reduced affective distress and increased adaptive coping use in both clinical and academic settings. Possible future directions for this research targeting student nurses are outlined in Chapter 7.
1998-01-01T00:00:00ZJones, Martyn C.Following a review of the stress, distress and coping reported by student health professionals and students in higher education, see Chapters 2 and 3, the hypothesis that a problem existed with distress early in training was confirmed by screening two cohorts of first year student nurses, see Chapter 4. Some 50.5% of students, in Cohort one (N=109, Week 40) and 67.9% of students in Cohort two (N=111, Week 24) suffered significant levels of affective distress. All students were enrolled on the newly implemented 1992 scheme of nurse education in Tayside. The underlying dimensions of situational sources reported by student nurse stress were clarified with the development of the Student Nurse Stress Index, see Chapter 5. A reliable 22 variable solution with oblique structure and non-orthogonal factors of "academic load", "clinical sources", "intet/ace worries", "personal problems" was obtained. This measure showed cross sample factor congruence, good internal reliabilities, and concurrent and discriminant validity across a range of reporting conditions. A stress reduction/management intervention set at individual and interface levels, designed to reduce levels of student nurse distress revealed by the earlier screening study, was implemented during a second series of hospital placements, see Chapter 6. A randomised controlled trial revealed the success of this programme in reducing affective distress in 73 student nurses shown to have experienced significant levels of distress earlier in training. A series of significant treatment x time interactions were found with a range of context-free measures of affective distress, e.g. General Health Questionnaire-30 (Goldberg, 1972), State and Trait Anxiety Inventory (Speilberger, et aI., 1983), Beck Depression Inventory (Beck, et aI., 1987), with situational sources of stress (Beck & Srivastava, 1991), and Domestic Satisfaction (Derogatis, 1980). Similar treatment x time interactions were found with Direct Coping (Parkes, 1984), and Relaxation Potential (Derogatis, 1980). Adaptive changes were confmed to the experimental group alone. In addition, State Anxiety on the morning of an important exam was lower for students receiving stress management (Treatment X= 45.88, Control X =59.09). The intervention had no detectable effect on organisational variables of sickness, absence and examination performance. However, logistic regression and hierarchical multiple regression analysis showed that initial distress at screen did not predict pre or post-treatment changes in sickness or absence, or subsequent examination performance. Stress management delivered in groups reduced affective distress and increased adaptive coping use in both clinical and academic settings. Possible future directions for this research targeting student nurses are outlined in Chapter 7.Cloning and characterisation of phospholipase C X-domain containing proteins (PLCXDs)Gellatly, Steven Alexanderhttps://hdl.handle.net/10023/70332019-04-01T08:52:34Z2015-01-01T00:00:00ZMembers of the phosphoinositide-specific phospholipase C (PI-PLC) enzyme family
play a fundamental role in cell signalling pathways by regulating cytosolic calcium
and/or the activity of several protein kinases. This thesis reports the identification,
molecular cloning and characterisation of a potential seventh sub-class of the PI-PLC
enzyme family, the phospholipase C X-domain containing proteins (PLCXDs), which
contain only an X domain in their structure. Comparative sequence analysis has
identified at least three PLCXD isoforms in the human and mouse genomes (PLCXDs 1,
2 and 3), and at least four isoforms in the European eel (PLCXDs 1-4). Key amino acid
residues responsible for the catalytic properties of PI-PLCs were found to be conserved
in human, mouse and eel PLCXDs 1, 2 and 3, but were absent in the sequence of eel
PLCXD4. PLCXD isoforms displayed unique tissue-specific expression profiles and some
similarities between species. Interestingly, in mouse PLCXD1-3 mRNA were found to
be predominantly expressed in the brain, however this is yet to be confirmed in
humans. Analysis of in situ hybridisation data in mice revealed each PLCXD to be
localised in neurons within different brain regions, highly suggestive of unique roles in
brain function. Furthermore, the levels of PLCXD3 protein were reduced by more than
99% in cerebella samples from a mouse model of neurodegeneration (Harlequin
mouse) compared to control mice. Human PLCXD1, 2 and 3 were found to increase
phosphoinositide turnover when overexpressed in the HeLa cell line, and recombinant
PLCXD3, purified to homogeneity from E. coli, was found to interact with various
phosphoinositides including PI(4,5)P₂. ³¹P-NMR analysis of PI(4,5)P₂ and PI before and
after the addition of PLCXD3 purified from HeLa cells and E. coli revealed no difference
in the ³¹P spectra whereas expected chemical shifts were seen following the addition
of purified bacterial PI-PLC. Significant formation of inclusion bodies was noted when
human PLCXDs 1, 2 and 3 were expressed as recombinant proteins in E. coli. Different
strategies aimed at optimising the expression of recombinant PLCXD1, 2 and 3,
including the use of different fusion proteins and screening expression in E. coli,
mammalian and insect cells had limited success, with the best soluble expression only
seen with PLCXD3 in insect cells. Attempts to scale-up the purification of PLCXD3 from
insect cells to provide sufficient protein for enzyme assays and crystal screens were
unsuccessful. The results presented herein suggest that these novel proteins possess
distinct and as yet uncharacterised tissue-specific roles in cell physiology.
2015-01-01T00:00:00ZGellatly, Steven AlexanderMembers of the phosphoinositide-specific phospholipase C (PI-PLC) enzyme family
play a fundamental role in cell signalling pathways by regulating cytosolic calcium
and/or the activity of several protein kinases. This thesis reports the identification,
molecular cloning and characterisation of a potential seventh sub-class of the PI-PLC
enzyme family, the phospholipase C X-domain containing proteins (PLCXDs), which
contain only an X domain in their structure. Comparative sequence analysis has
identified at least three PLCXD isoforms in the human and mouse genomes (PLCXDs 1,
2 and 3), and at least four isoforms in the European eel (PLCXDs 1-4). Key amino acid
residues responsible for the catalytic properties of PI-PLCs were found to be conserved
in human, mouse and eel PLCXDs 1, 2 and 3, but were absent in the sequence of eel
PLCXD4. PLCXD isoforms displayed unique tissue-specific expression profiles and some
similarities between species. Interestingly, in mouse PLCXD1-3 mRNA were found to
be predominantly expressed in the brain, however this is yet to be confirmed in
humans. Analysis of in situ hybridisation data in mice revealed each PLCXD to be
localised in neurons within different brain regions, highly suggestive of unique roles in
brain function. Furthermore, the levels of PLCXD3 protein were reduced by more than
99% in cerebella samples from a mouse model of neurodegeneration (Harlequin
mouse) compared to control mice. Human PLCXD1, 2 and 3 were found to increase
phosphoinositide turnover when overexpressed in the HeLa cell line, and recombinant
PLCXD3, purified to homogeneity from E. coli, was found to interact with various
phosphoinositides including PI(4,5)P₂. ³¹P-NMR analysis of PI(4,5)P₂ and PI before and
after the addition of PLCXD3 purified from HeLa cells and E. coli revealed no difference
in the ³¹P spectra whereas expected chemical shifts were seen following the addition
of purified bacterial PI-PLC. Significant formation of inclusion bodies was noted when
human PLCXDs 1, 2 and 3 were expressed as recombinant proteins in E. coli. Different
strategies aimed at optimising the expression of recombinant PLCXD1, 2 and 3,
including the use of different fusion proteins and screening expression in E. coli,
mammalian and insect cells had limited success, with the best soluble expression only
seen with PLCXD3 in insect cells. Attempts to scale-up the purification of PLCXD3 from
insect cells to provide sufficient protein for enzyme assays and crystal screens were
unsuccessful. The results presented herein suggest that these novel proteins possess
distinct and as yet uncharacterised tissue-specific roles in cell physiology.The primary prevention of violence in secondary school pupils in the West of ScotlandGavine, Anna Janehttps://hdl.handle.net/10023/65442019-04-01T08:53:39Z2014-06-27T00:00:00ZViolence is a leading cause of morbidity and mortality amongst young people. Public health approaches are now being increasingly utilised to reduce the risk of young peoples’ involvement in violence. One such programme is Medics Against Violence (MAV), which aims to reduce pro-violent attitudes and enhance empathy in secondary school pupils. This thesis aims to investigate whether this approach can be effective in tackling youth violence in secondary school pupils.
A mixed-methods approach was adopted to conduct both an outcome and process evaluation of MAV. Four schools took part in the outcome evaluation, which examined whether there was a change in attitudes towards violence or empathy in pupils receiving the MAV programme. The process evaluation consisted of focus groups with school pupils, and open-ended questionnaires and semi-structured interviews with MAV volunteers.
There was a small but significant reduction in pro-violent attitudes immediately post-intervention. However, this was not sustained at three months and there was no significant increase in empathy scores. Pupils generally demonstrated anti-violent attitudes, although were more likely to support the use of reactive violence. The pupils appeared to enjoy and generally engage well with the programme. In particular, the use of real footage, interviews with those affected by violence and the Glasgow setting provided a sense of realism for the pupils. Moreover, pupils valued the opportunity to discuss the issues raised by MAV with the volunteers. Volunteers felt engagement was occasionally an issue in the most affluent areas. However, some volunteers adapted the programme to focus on victimisation prevention in the most affluent schools. Further development is therefore needed in terms of establishing who the programme is aimed at (i.e. potential victims or perpetrators), focusing on reactive violence and increasing the sustainability of its effects.
2014-06-27T00:00:00ZGavine, Anna JaneViolence is a leading cause of morbidity and mortality amongst young people. Public health approaches are now being increasingly utilised to reduce the risk of young peoples’ involvement in violence. One such programme is Medics Against Violence (MAV), which aims to reduce pro-violent attitudes and enhance empathy in secondary school pupils. This thesis aims to investigate whether this approach can be effective in tackling youth violence in secondary school pupils.
A mixed-methods approach was adopted to conduct both an outcome and process evaluation of MAV. Four schools took part in the outcome evaluation, which examined whether there was a change in attitudes towards violence or empathy in pupils receiving the MAV programme. The process evaluation consisted of focus groups with school pupils, and open-ended questionnaires and semi-structured interviews with MAV volunteers.
There was a small but significant reduction in pro-violent attitudes immediately post-intervention. However, this was not sustained at three months and there was no significant increase in empathy scores. Pupils generally demonstrated anti-violent attitudes, although were more likely to support the use of reactive violence. The pupils appeared to enjoy and generally engage well with the programme. In particular, the use of real footage, interviews with those affected by violence and the Glasgow setting provided a sense of realism for the pupils. Moreover, pupils valued the opportunity to discuss the issues raised by MAV with the volunteers. Volunteers felt engagement was occasionally an issue in the most affluent areas. However, some volunteers adapted the programme to focus on victimisation prevention in the most affluent schools. Further development is therefore needed in terms of establishing who the programme is aimed at (i.e. potential victims or perpetrators), focusing on reactive violence and increasing the sustainability of its effects.An investigation using cultured human cell lines, of the involvement of vanadium, cation transport and phosphatidylinositol in the aetiology of bipolar manic-depressive psychosisBanks, Rosamonde ElizabethNaylor, Grahamhttps://hdl.handle.net/10023/64262019-07-01T10:16:14Z1986-12-01T00:00:00ZThe symptoms, classification, occurrence and possible aetiologies of bipolar manic-depressive psychosis have been reviewed, with particular emphasis on the possible role of the vanadate ion (V5+) and cation transport in the illness. The effect of vanadate on cation transport in intact cells has been determined using the well-characterised HeLa cell line. Cation transport in virally transformed lymphoblastoid cell lines from 13 bipolar manic-depressive patients and 13 control subjects has been examined, under normal conditions and after treatment (24 hours) with lithium, ouabain or vanadate. The phosphatidylinositol system has also been examined in these cell lines, in view of the therapeutic effect of lithium, and its known inhibitory actions on inositol I-phosphatase.
In HeLa cells, no effects of vanadate on cation transport were seen until concentrations greater than 3.2 x 10- 6 M. This was attributed to the intracellular reduction of V5+ to V4+ shown to occur using ESR. Similar decreases were seen in all the K+ influx pathways, with maximum decreases of approximately 30% at 10-4M vanadate extracellularly. Significant toxicity was also seen at these concentrations, with a maximum decrease in cell number of 40% at 10-4M vanadate. No change in the energy charge was seen and changes in ATP levels occurred subsequently to the changes in cell number, with a decrease of 40% at 10-4M vanadate.
Using the lymphoblastoid cell lines, no significant differences were seen in any of the cation transport parameters examined, with the exception of mean sodium pump number which was 30% greater in the bipolar group compared with the control group. Lithium or vanadate treatment produced either no effect or inconsistent changes in cation transport. Ouabain treatment produced similar decreases in sodium pump number in both groups.
Inositol uptake was similar in both groups, but the percentage incorporation into phosphoinositides was reduced in bipolar cell lines compared with controls.
1986-12-01T00:00:00ZBanks, Rosamonde ElizabethNaylor, GrahamThe symptoms, classification, occurrence and possible aetiologies of bipolar manic-depressive psychosis have been reviewed, with particular emphasis on the possible role of the vanadate ion (V5+) and cation transport in the illness. The effect of vanadate on cation transport in intact cells has been determined using the well-characterised HeLa cell line. Cation transport in virally transformed lymphoblastoid cell lines from 13 bipolar manic-depressive patients and 13 control subjects has been examined, under normal conditions and after treatment (24 hours) with lithium, ouabain or vanadate. The phosphatidylinositol system has also been examined in these cell lines, in view of the therapeutic effect of lithium, and its known inhibitory actions on inositol I-phosphatase.
In HeLa cells, no effects of vanadate on cation transport were seen until concentrations greater than 3.2 x 10- 6 M. This was attributed to the intracellular reduction of V5+ to V4+ shown to occur using ESR. Similar decreases were seen in all the K+ influx pathways, with maximum decreases of approximately 30% at 10-4M vanadate extracellularly. Significant toxicity was also seen at these concentrations, with a maximum decrease in cell number of 40% at 10-4M vanadate. No change in the energy charge was seen and changes in ATP levels occurred subsequently to the changes in cell number, with a decrease of 40% at 10-4M vanadate.
Using the lymphoblastoid cell lines, no significant differences were seen in any of the cation transport parameters examined, with the exception of mean sodium pump number which was 30% greater in the bipolar group compared with the control group. Lithium or vanadate treatment produced either no effect or inconsistent changes in cation transport. Ouabain treatment produced similar decreases in sodium pump number in both groups.
Inositol uptake was similar in both groups, but the percentage incorporation into phosphoinositides was reduced in bipolar cell lines compared with controls.The role of CTCF in the life cycle of human papillomavirusParis, Christianhttps://hdl.handle.net/10023/63672019-12-09T14:30:43Z2014-06-27T00:00:00ZPapillomaviruses (PV) are epithelium specific DNA viruses that can cause health problems ranging from harmless warts to invasive cancer. Papillomavirus induced tumours most often arise in the cervix where human papillomavirus (HPV) infections were shown to cause 99.7 % of all malignancies.
This study aims to map binding sites of the multifunctional host protein CCCTC binding factor (CTCF) to the papillomavirus genome, validate them and determine the function of CTCF in the papillomavirus life cycle. Computer predictions of CTCF binding sites in the sequence of 8 different PV revealed a CTCF binding pattern including a conserved high-affinity binding site around nucleotide 3000 in high risk HPV and around nucleotide 5400 in low risk HPV. This binding pattern was experimentally confirmed using electrophoretic mobility shift assays (EMSA). The binding site around nucleotide 3000 in HPV18 was mutated and human foreskin keratinocytes (HFK) were transfected with mutant and wild type HPV18 to analyse the effect of the mutation on viral gene expression and life cycle. Western blotting of methylcellulose differentiated HFK revealed earlier expression of E2 and decreased expression of E1^E4 in the mutant compared to the wild type. Immunostaining of organotypic raft cultures grown from the mutant maintaining cells showed a significant increase in proliferating cells compared to the HFK maintaining the wild type. This was accompanied by pseudo-differentiation of keratinocytes since the cells of the granular layer of the raft expressed the terminal differentiation marker loricrin but maintained the morphology of undifferentiated cells. Thus CTCF was shown to have a major impact on the HPV life cycle and it may play a role in HPV induced carcinogenesis. Furthermore a function of CTCF in long term maintenance of the viral episome was revealed as cells maintaining the CTCF mutant were shown to lose episomes more quickly compared to wild type maintaining cells.
2014-06-27T00:00:00ZParis, ChristianPapillomaviruses (PV) are epithelium specific DNA viruses that can cause health problems ranging from harmless warts to invasive cancer. Papillomavirus induced tumours most often arise in the cervix where human papillomavirus (HPV) infections were shown to cause 99.7 % of all malignancies.
This study aims to map binding sites of the multifunctional host protein CCCTC binding factor (CTCF) to the papillomavirus genome, validate them and determine the function of CTCF in the papillomavirus life cycle. Computer predictions of CTCF binding sites in the sequence of 8 different PV revealed a CTCF binding pattern including a conserved high-affinity binding site around nucleotide 3000 in high risk HPV and around nucleotide 5400 in low risk HPV. This binding pattern was experimentally confirmed using electrophoretic mobility shift assays (EMSA). The binding site around nucleotide 3000 in HPV18 was mutated and human foreskin keratinocytes (HFK) were transfected with mutant and wild type HPV18 to analyse the effect of the mutation on viral gene expression and life cycle. Western blotting of methylcellulose differentiated HFK revealed earlier expression of E2 and decreased expression of E1^E4 in the mutant compared to the wild type. Immunostaining of organotypic raft cultures grown from the mutant maintaining cells showed a significant increase in proliferating cells compared to the HFK maintaining the wild type. This was accompanied by pseudo-differentiation of keratinocytes since the cells of the granular layer of the raft expressed the terminal differentiation marker loricrin but maintained the morphology of undifferentiated cells. Thus CTCF was shown to have a major impact on the HPV life cycle and it may play a role in HPV induced carcinogenesis. Furthermore a function of CTCF in long term maintenance of the viral episome was revealed as cells maintaining the CTCF mutant were shown to lose episomes more quickly compared to wild type maintaining cells.Structural and functional studies of histidine-rich glycoprotein in relation to its roles in angiogenesis and coagulationKassaar, Omarhttps://hdl.handle.net/10023/55482019-04-01T08:53:38Z2014-12-01T00:00:00ZHistidine-rich glycoprotein (HRG) is a plasma protein that regulates key cardiovascular processes such as coagulation, angiogenesis and immune response. The protein consists of six distinct functional domains: two N-terminal domains (N1 and N2), two proline-rich regions (PRR1 and PRR2), a central histidine-rich region (HRR) and a C-terminal domain. The HRR binds Zn²⁺, which alters the affinity of HRG towards various ligands including the anticoagulant, heparin.
A key aim of this study was to structurally characterise HRG. The 1.93 Å crystal structure of the HRG N2 domain presented here represents the first crystallographic snapshot of the molecule. The N2 domain is cystatin-like and N-glycosylated at Asn184. An S-glutathionyl adduct was observed at Cys185, providing in vivo evidence that release of an anti-angiogenic HRR/PRR fragment is controlled in part by a redox mechanism, representing a novel further role for GSH in regulation of angiogenesis.
Since Zn²⁺ regulates some of the functions of HRG, the dynamics of Zn²⁺ in plasma were investigated using a combination of ITC, ELISA and thrombin assay systems. Zn²⁺ is normally associated with albumin in circulation, but its ability to bind Zn²⁺ is allosterically inhibited upon fatty acids binding to albumin. Elevated plasma fatty acid levels are associated with some disease states. It is proposed that this may alter the proportion of Zn²⁺ bound to HRG, which could in turn activate thrombin to promote coagulation. These studies provide evidence to suggest that Zn²⁺-dependent activation of HRG (following fatty acid binding to albumin) may play a role in the development of haemostatic complications in susceptible individuals.
Finally, the Zn²⁺ binding ability of albumin was probed in order to locate unidentified sites using recombinant albumin mutants. H9A, H67A, E252A, D256A and H288A mutants all exhibited diminished Zn²⁺ binding ability, indicating that these residues are involved directly or indirectly in Zn²⁺ binding.
2014-12-01T00:00:00ZKassaar, OmarHistidine-rich glycoprotein (HRG) is a plasma protein that regulates key cardiovascular processes such as coagulation, angiogenesis and immune response. The protein consists of six distinct functional domains: two N-terminal domains (N1 and N2), two proline-rich regions (PRR1 and PRR2), a central histidine-rich region (HRR) and a C-terminal domain. The HRR binds Zn²⁺, which alters the affinity of HRG towards various ligands including the anticoagulant, heparin.
A key aim of this study was to structurally characterise HRG. The 1.93 Å crystal structure of the HRG N2 domain presented here represents the first crystallographic snapshot of the molecule. The N2 domain is cystatin-like and N-glycosylated at Asn184. An S-glutathionyl adduct was observed at Cys185, providing in vivo evidence that release of an anti-angiogenic HRR/PRR fragment is controlled in part by a redox mechanism, representing a novel further role for GSH in regulation of angiogenesis.
Since Zn²⁺ regulates some of the functions of HRG, the dynamics of Zn²⁺ in plasma were investigated using a combination of ITC, ELISA and thrombin assay systems. Zn²⁺ is normally associated with albumin in circulation, but its ability to bind Zn²⁺ is allosterically inhibited upon fatty acids binding to albumin. Elevated plasma fatty acid levels are associated with some disease states. It is proposed that this may alter the proportion of Zn²⁺ bound to HRG, which could in turn activate thrombin to promote coagulation. These studies provide evidence to suggest that Zn²⁺-dependent activation of HRG (following fatty acid binding to albumin) may play a role in the development of haemostatic complications in susceptible individuals.
Finally, the Zn²⁺ binding ability of albumin was probed in order to locate unidentified sites using recombinant albumin mutants. H9A, H67A, E252A, D256A and H288A mutants all exhibited diminished Zn²⁺ binding ability, indicating that these residues are involved directly or indirectly in Zn²⁺ binding.A mixed methods investigation of perceptions of adulthood and gender : links to stereotyped and risky behaviours amongst young people in Kirkcaldy, FifePopple, Helenhttps://hdl.handle.net/10023/44962019-07-01T10:15:57Z2014-02-05T00:00:00ZAdolescence is a formative period of identity development. From the start of high school young people begin to direct their own development through peer selection and behavioural choices. During this time young people have the opportunity to engage in risky behaviours such as drinking alcohol, smoking, having unprotected sex and taking illegal drugs, for the first time. These behaviours amongst young people have been linked to a range of adverse health and wellbeing outcomes, both short and long term.
This study seeks to improve understanding of eleven to fifteen year olds’ behavioural choices through investigation of potential links to perceptions of adulthood and gender. In order to capture this more fully a mixed methods approach is used with a quantitative cross-sectional pupil survey and in-depth intergenerational family qualitative interviews. By exploring a broad range of age and gender stereotyped, and risky behaviours, this study seeks to provide better understanding of participants’ perceptions, motivations and involvement in these behaviours.
Results of the study demonstrate both gendered and age differentiated patterns of perceptions. Between eleven and fifteen years old, boys demonstrate more pronounced values attributed to masculine roles. Conversely, stereotyped feminine roles appear to decrease in appeal to girls. Fourth year girls perceive risky behaviours as considerably more relevant to them, than their male peers. Interviewed mothers were unsure of how best to manage their daughter’s behaviours considering their own lack of experience and the apparently high value attributed to non-confrontational, friendship based, mothering.
Current methods of teaching and intervening generally address mixed gender age-group classes. This research suggests in order to modify risk-taking behaviours a gender specific approach may be more effective.
2014-02-05T00:00:00ZPopple, HelenAdolescence is a formative period of identity development. From the start of high school young people begin to direct their own development through peer selection and behavioural choices. During this time young people have the opportunity to engage in risky behaviours such as drinking alcohol, smoking, having unprotected sex and taking illegal drugs, for the first time. These behaviours amongst young people have been linked to a range of adverse health and wellbeing outcomes, both short and long term.
This study seeks to improve understanding of eleven to fifteen year olds’ behavioural choices through investigation of potential links to perceptions of adulthood and gender. In order to capture this more fully a mixed methods approach is used with a quantitative cross-sectional pupil survey and in-depth intergenerational family qualitative interviews. By exploring a broad range of age and gender stereotyped, and risky behaviours, this study seeks to provide better understanding of participants’ perceptions, motivations and involvement in these behaviours.
Results of the study demonstrate both gendered and age differentiated patterns of perceptions. Between eleven and fifteen years old, boys demonstrate more pronounced values attributed to masculine roles. Conversely, stereotyped feminine roles appear to decrease in appeal to girls. Fourth year girls perceive risky behaviours as considerably more relevant to them, than their male peers. Interviewed mothers were unsure of how best to manage their daughter’s behaviours considering their own lack of experience and the apparently high value attributed to non-confrontational, friendship based, mothering.
Current methods of teaching and intervening generally address mixed gender age-group classes. This research suggests in order to modify risk-taking behaviours a gender specific approach may be more effective.International studies in violence prevention : a policy analysisMorris Gehring, Alisonhttps://hdl.handle.net/10023/44702019-04-01T08:53:46Z2013-01-01T00:00:00ZViolence is a leading cause of death and disability worldwide. Drawing on the
disciplines of Political Science and Public Health the purpose of this study is to
understand the conditions that determine political traction for the issue of violence
and facilitate the adoption of a strategy of prevention. Using multiple-case study
methodology, it draws on data collected from 42 in-depth semi-structured
interviews, eight weeks of direct observations and more than 200 pieces of
documentary evidence to examine violence prevention policy development in the
Western Cape Province of South Africa, Jamaica and the Republic of Lithuania.
The Shiffman Public Health Policy Priority Framework is applied to identify the
factors that influenced the advancement of violence prevention policy in each case
and to draw cross-case comparisons. The employment of this public health specific
framework in the field of violence prevention allows the study to reach conclusions
as to the utility of this framework for broader public health policy analysis and to
proffer some refinements.
Further findings suggest that bringing together academics, advocates and policy-
makers into networks, focused on a shared concept of violence, gains political
traction for the issue of violence and a strategy of prevention. It is found that the
conceptualisation of violence and perception of prevention are framed in a case
specific historical context and that an examination of this context is necessary to
understand the conditions that shape the status of violence prevention policy.
The results suggest that the development of violence prevention policy in other
countries would be expedited by the coalescing and informed engagement of the
violence prevention policy community in the web of institutions, interests and ideas
that underpin the public health policy process.
2013-01-01T00:00:00ZMorris Gehring, AlisonViolence is a leading cause of death and disability worldwide. Drawing on the
disciplines of Political Science and Public Health the purpose of this study is to
understand the conditions that determine political traction for the issue of violence
and facilitate the adoption of a strategy of prevention. Using multiple-case study
methodology, it draws on data collected from 42 in-depth semi-structured
interviews, eight weeks of direct observations and more than 200 pieces of
documentary evidence to examine violence prevention policy development in the
Western Cape Province of South Africa, Jamaica and the Republic of Lithuania.
The Shiffman Public Health Policy Priority Framework is applied to identify the
factors that influenced the advancement of violence prevention policy in each case
and to draw cross-case comparisons. The employment of this public health specific
framework in the field of violence prevention allows the study to reach conclusions
as to the utility of this framework for broader public health policy analysis and to
proffer some refinements.
Further findings suggest that bringing together academics, advocates and policy-
makers into networks, focused on a shared concept of violence, gains political
traction for the issue of violence and a strategy of prevention. It is found that the
conceptualisation of violence and perception of prevention are framed in a case
specific historical context and that an examination of this context is necessary to
understand the conditions that shape the status of violence prevention policy.
The results suggest that the development of violence prevention policy in other
countries would be expedited by the coalescing and informed engagement of the
violence prevention policy community in the web of institutions, interests and ideas
that underpin the public health policy process.An investigation into the job leaving intentions and occupational-related attitudes among dental nurses in Scotland : the mediating role of work engagement and personal accomplishmentForbes, Gillian MacKenziehttps://hdl.handle.net/10023/36002019-04-01T08:52:37Z2012-01-01T00:00:00ZBackground: Studies have investigated work engagement in dentistry, however dental
nurse engagement is still inadequately understood. Also concerns about low retention
and shortages of dental nurses in the UK have been highlighted. The purpose of this
dissertation was two-fold. First is to build on the existing understanding of the mediating role of work engagement and personal accomplishment between
occupational-related attitudes and leaving intentions. Secondly, to explore which of the
specific occupational-related attitudes of dental nurses support and encourage a dental
nursing career.
Aims: The research had 3 aims. (1) To address the lack of information on work
engagement among dental nurses, (2) To understand which job resources are important
in the work-place and (3) to investigate how these job resources relate to work
engagement and personal accomplishment and in turn their relationship with future
intentions to leave the profession.
Method: A sequential exploratory design of mixed methods was employed to collect data
by first exploring the work experiences using focus groups of 24 dental nurses, either undergoing registration training or further post-registration qualification courses in 2 locations. Secondly, a newly designed cross-sectional questionnaire investigated demographics, job demands and resources, work engagement and personal
accomplishment (using Utrecht Work Engagement Scale and the Maslach Burnout
Inventory respectively) and an adapted measure of intention-to-leave of a sample of 269 dental nurses in Scotland (pre-registration n = 241; post registration n = 28).
Results: A major theme was opinion surrounding the introduction of registration in August 2009. Registration for pre-registration dental nurses had a personal impact whereas post-registration dental nurses expressed a benefit for the whole profession. A common theme emerging from both groups of dental nurses was the provision of a clearer career pathway. Influences on leaving for pre-registration dental nurses were not being part of an integrated dental team and no sense of feeling valued. An uncovered underlying theme was the concept of professionalism. Pre-registration dental nurses sought support and security. This opinion contrasted with that of the post-registration
group who appreciated a greater sense of independency. In the questionnaire the overall response rate was 82% based on pre-registration dental nurses only. Pre-registration dental nurses’ work engagement scores were more dedicated (p < 0.0001), and absorbed (p < 0.007) and had less vigour (p < 0.0001) when compared to UWES manual norm values. Work engagement had a mediating role between job resources and intention-to-leave. The job resources predicting higher work engagement were positive beliefs about registration, task significance and variety, and low repetition in the daily routine.
Conclusion: There was some evidence that a professional process occurs during registration training which may be indicative of future intentions to remain in dental nursing. Contextual job resources were more salient in supporting work engagement. Work engagement is a key indicator of intention-to-leave whilst high personal accomplishment predicted high intention-to-leave. Also some evidence suggested job resources may act indirectly on intention-to-leave.
2012-01-01T00:00:00ZForbes, Gillian MacKenzieBackground: Studies have investigated work engagement in dentistry, however dental
nurse engagement is still inadequately understood. Also concerns about low retention
and shortages of dental nurses in the UK have been highlighted. The purpose of this
dissertation was two-fold. First is to build on the existing understanding of the mediating role of work engagement and personal accomplishment between
occupational-related attitudes and leaving intentions. Secondly, to explore which of the
specific occupational-related attitudes of dental nurses support and encourage a dental
nursing career.
Aims: The research had 3 aims. (1) To address the lack of information on work
engagement among dental nurses, (2) To understand which job resources are important
in the work-place and (3) to investigate how these job resources relate to work
engagement and personal accomplishment and in turn their relationship with future
intentions to leave the profession.
Method: A sequential exploratory design of mixed methods was employed to collect data
by first exploring the work experiences using focus groups of 24 dental nurses, either undergoing registration training or further post-registration qualification courses in 2 locations. Secondly, a newly designed cross-sectional questionnaire investigated demographics, job demands and resources, work engagement and personal
accomplishment (using Utrecht Work Engagement Scale and the Maslach Burnout
Inventory respectively) and an adapted measure of intention-to-leave of a sample of 269 dental nurses in Scotland (pre-registration n = 241; post registration n = 28).
Results: A major theme was opinion surrounding the introduction of registration in August 2009. Registration for pre-registration dental nurses had a personal impact whereas post-registration dental nurses expressed a benefit for the whole profession. A common theme emerging from both groups of dental nurses was the provision of a clearer career pathway. Influences on leaving for pre-registration dental nurses were not being part of an integrated dental team and no sense of feeling valued. An uncovered underlying theme was the concept of professionalism. Pre-registration dental nurses sought support and security. This opinion contrasted with that of the post-registration
group who appreciated a greater sense of independency. In the questionnaire the overall response rate was 82% based on pre-registration dental nurses only. Pre-registration dental nurses’ work engagement scores were more dedicated (p < 0.0001), and absorbed (p < 0.007) and had less vigour (p < 0.0001) when compared to UWES manual norm values. Work engagement had a mediating role between job resources and intention-to-leave. The job resources predicting higher work engagement were positive beliefs about registration, task significance and variety, and low repetition in the daily routine.
Conclusion: There was some evidence that a professional process occurs during registration training which may be indicative of future intentions to remain in dental nursing. Contextual job resources were more salient in supporting work engagement. Work engagement is a key indicator of intention-to-leave whilst high personal accomplishment predicted high intention-to-leave. Also some evidence suggested job resources may act indirectly on intention-to-leave.Polycomb proteins and breast cancerFedele, Vitahttps://hdl.handle.net/10023/35842019-04-01T08:52:37Z2012-01-01T00:00:00ZIn the Western world, breast cancer is the most frequent malignancy in women and still the leading cause of cancer related deaths, therefore, a better understanding of the disease is needed. Adequate therapeutic targets for all breast cancer types have not been identified yet, and patients with the same type of cancer have often different outcomes. Polycomb proteins are emerging as important factors involved in breast cancer formation. Polycomb proteins play a crucial role in embryogenesis, early development, stem cell renewal and establishing and maintaining cell identity. Their alteration leads to mis-regulation of several important cellular factors including tumour suppressors, DNA repair factors, cell cycle regulation factors and cell-cell interaction factors.
In this thesis the importance of several polycomb proteins in breast cancer has been investigated. The effect of EZH2 knockdown has been tested in breast cancer cell lines expressing different level of the protein and with different features. The results obtained are in line with other studies and suggest that the effect of EZH2 down-regulation in breast cancer cells is dependent on cellular context. In vitro experiments, using both established breast cell lines and primary epithelial cells have been used for investigating the importance of CBX8 in breast cancer. The results obtained showed that the polycomb proteins CBX8 does not play a central role in malignant transformation of the mammary epithelial cells tested.
2012-01-01T00:00:00ZFedele, VitaIn the Western world, breast cancer is the most frequent malignancy in women and still the leading cause of cancer related deaths, therefore, a better understanding of the disease is needed. Adequate therapeutic targets for all breast cancer types have not been identified yet, and patients with the same type of cancer have often different outcomes. Polycomb proteins are emerging as important factors involved in breast cancer formation. Polycomb proteins play a crucial role in embryogenesis, early development, stem cell renewal and establishing and maintaining cell identity. Their alteration leads to mis-regulation of several important cellular factors including tumour suppressors, DNA repair factors, cell cycle regulation factors and cell-cell interaction factors.
In this thesis the importance of several polycomb proteins in breast cancer has been investigated. The effect of EZH2 knockdown has been tested in breast cancer cell lines expressing different level of the protein and with different features. The results obtained are in line with other studies and suggest that the effect of EZH2 down-regulation in breast cancer cells is dependent on cellular context. In vitro experiments, using both established breast cell lines and primary epithelial cells have been used for investigating the importance of CBX8 in breast cancer. The results obtained showed that the polycomb proteins CBX8 does not play a central role in malignant transformation of the mammary epithelial cells tested.Biochemical and functional characterisation of phospholipase C-η2Popovics, Petrahttps://hdl.handle.net/10023/35112019-04-01T08:52:21Z2013-06-28T00:00:00ZPhospholipase C enzymes are important cell signalling enzymes that catalyse the cleavage of phosphatidylinositol 4,5-bisphophate PI(4,5)P₂ into two biologically active second messenger molecules. These are the inositol 1,4,5-trisphosphate which initiates Ca²⁺ release from the endoplasmic reticulum and the diacylglycerol that activates protein kinase C. Although this basic function is shared between the different isoforms, the PLC family encompasses a diverse collection of proteins with various domain structures in addition to the PLC-specific domains.
The neuron-specific “6th family” of these enzymes, PLCηs have most recently been identified with two members, PLCη1 and PLCη2. The aim of the thesis is to characterise the PLCη2 variant from several aspects. Firstly, it describes that PLCη2 possesses a high sensitivity towards Ca²⁺. Secondly, it investigates how the Ca²⁺-induced enzymatic activity of PLCη2 is controlled by its different domains. Also it provides evidence that the pleckstrin homology domain targets PLCη2 to membranes by recognising PI(3,4,5)P₃. Moreover, the uniquely structured EF-hand is responsible for the Ca²⁺-sensitivity of the enzyme. Finally, it is demonstrated that the C2 domain is important for activity.
The initial biochemical characterisation is followed by the description of a physiological role for PLCη2. It is shown using a neuroblast model that PLCη2 is crucial for neuronal differentiation and neurite growth. Further efforts were made to assess how PLCη2 is responsible for this effect. It was revealed that it might be involved in regulating intracellular Ca²⁺ dynamics, transcriptional activity and actin reorganisation in differentiating neurons.
As the functions of PLCη2 are just beginning to come to light, more aspects for future research are also suggested in the thesis. Hopefully, this and the data presented within the thesis will stimulate even greater interest in this fascinating new field of research.
2013-06-28T00:00:00ZPopovics, PetraPhospholipase C enzymes are important cell signalling enzymes that catalyse the cleavage of phosphatidylinositol 4,5-bisphophate PI(4,5)P₂ into two biologically active second messenger molecules. These are the inositol 1,4,5-trisphosphate which initiates Ca²⁺ release from the endoplasmic reticulum and the diacylglycerol that activates protein kinase C. Although this basic function is shared between the different isoforms, the PLC family encompasses a diverse collection of proteins with various domain structures in addition to the PLC-specific domains.
The neuron-specific “6th family” of these enzymes, PLCηs have most recently been identified with two members, PLCη1 and PLCη2. The aim of the thesis is to characterise the PLCη2 variant from several aspects. Firstly, it describes that PLCη2 possesses a high sensitivity towards Ca²⁺. Secondly, it investigates how the Ca²⁺-induced enzymatic activity of PLCη2 is controlled by its different domains. Also it provides evidence that the pleckstrin homology domain targets PLCη2 to membranes by recognising PI(3,4,5)P₃. Moreover, the uniquely structured EF-hand is responsible for the Ca²⁺-sensitivity of the enzyme. Finally, it is demonstrated that the C2 domain is important for activity.
The initial biochemical characterisation is followed by the description of a physiological role for PLCη2. It is shown using a neuroblast model that PLCη2 is crucial for neuronal differentiation and neurite growth. Further efforts were made to assess how PLCη2 is responsible for this effect. It was revealed that it might be involved in regulating intracellular Ca²⁺ dynamics, transcriptional activity and actin reorganisation in differentiating neurons.
As the functions of PLCη2 are just beginning to come to light, more aspects for future research are also suggested in the thesis. Hopefully, this and the data presented within the thesis will stimulate even greater interest in this fascinating new field of research.The study of exosomes and microvesicles secreted from breast cancer cell linesZheng, Yinghttps://hdl.handle.net/10023/34642019-04-01T08:52:39Z2012-11-30T00:00:00ZExosomes are small secreted vesicles of endocytic origin with a size range of 50-150 nm. They are secreted by many cell types and display multiple biological functions including immune-activation, immune-suppression, antigen presentation, and the shuttling of mRNA and miRNA, as well as other cargo. We have characterised the exosomes secreted from two breast cancer cell lines, MDA-MB-231 and MCF7. Exosomes secreted from both cell lines display typical markers including ALIX, Tsg101, CD9 and CD63, and were capable of inducing apoptosis of the Jurkat T cell line, indicating the potential immune-suppressive function of such tumour-derived exosomes. To further investigate the biological potential of exosomes, we loaded purified exosomes with gene specific siRNAs using electroporation, and observed the targeted inhibition of both a known component of the exosome pathway, Rab27a, and also the arthritis associated gene ERAP1, demonstrating the potential novel use of exosomes as therapeutic gene delivery vectors. We have also shown that exosomes derived from MDA-MB-231 cells and the parental cells have different lipid composition, as analysed by lipidomics study.
Nanoparticle tracking analysis (NTA), which allows the rapid detection of size and concentration of nanoparticles within the size range 10 nm-1000 nm was tested for its ability to accurately measure size and concentration of exosomes and microvesicles under different conditions. NTA was capable of detecting apoptotic vesicles induced by Taxol and Curcumin treatment. Immunodepletion was used to determine the percentage of CD9 and CD63 positive vesicles. Our data suggest that NTA is a useful technique for measuring size and concentration of exosomes and microvesicles. We hypothesized that NTA could assist in the screening of agents that interfere or promote exosome release. NTA was therefore used to detect increases in exosomes secretion induced by Tamoxifen and Thimerosal treatment, and to monitor the inhibition of exosome secretion from MDA-MB-231 breast cancer cells expressing inhibitory RNA targeted for Rab27a, a component of the exosome pathway. Increases in exosome release induced by Tamoxifen and Thimerosal was detected by NTA and a significant reduction in the release of exosomes by inhibition of Rab27a expression was also observed. Treatment with the known exosomal pathway inhibitor DMA also reduced exosome release, establishing the principle of NTA as a screening technique. We further compared the siRNA targeted cells for their ability to migrate, invade and form anchorage-independent colonies, which were all significantly reduced. Supplementation with MDA-MB-231 derived exosomes restored the ability to form colonies, suggesting exosomes may contribute to metastatic lesion formation. These data suggest that the exosomal pathway is a valid target to disrupt the behaviour of tumour cells and NTA can be used to monitor its activity.
2012-11-30T00:00:00ZZheng, YingExosomes are small secreted vesicles of endocytic origin with a size range of 50-150 nm. They are secreted by many cell types and display multiple biological functions including immune-activation, immune-suppression, antigen presentation, and the shuttling of mRNA and miRNA, as well as other cargo. We have characterised the exosomes secreted from two breast cancer cell lines, MDA-MB-231 and MCF7. Exosomes secreted from both cell lines display typical markers including ALIX, Tsg101, CD9 and CD63, and were capable of inducing apoptosis of the Jurkat T cell line, indicating the potential immune-suppressive function of such tumour-derived exosomes. To further investigate the biological potential of exosomes, we loaded purified exosomes with gene specific siRNAs using electroporation, and observed the targeted inhibition of both a known component of the exosome pathway, Rab27a, and also the arthritis associated gene ERAP1, demonstrating the potential novel use of exosomes as therapeutic gene delivery vectors. We have also shown that exosomes derived from MDA-MB-231 cells and the parental cells have different lipid composition, as analysed by lipidomics study.
Nanoparticle tracking analysis (NTA), which allows the rapid detection of size and concentration of nanoparticles within the size range 10 nm-1000 nm was tested for its ability to accurately measure size and concentration of exosomes and microvesicles under different conditions. NTA was capable of detecting apoptotic vesicles induced by Taxol and Curcumin treatment. Immunodepletion was used to determine the percentage of CD9 and CD63 positive vesicles. Our data suggest that NTA is a useful technique for measuring size and concentration of exosomes and microvesicles. We hypothesized that NTA could assist in the screening of agents that interfere or promote exosome release. NTA was therefore used to detect increases in exosomes secretion induced by Tamoxifen and Thimerosal treatment, and to monitor the inhibition of exosome secretion from MDA-MB-231 breast cancer cells expressing inhibitory RNA targeted for Rab27a, a component of the exosome pathway. Increases in exosome release induced by Tamoxifen and Thimerosal was detected by NTA and a significant reduction in the release of exosomes by inhibition of Rab27a expression was also observed. Treatment with the known exosomal pathway inhibitor DMA also reduced exosome release, establishing the principle of NTA as a screening technique. We further compared the siRNA targeted cells for their ability to migrate, invade and form anchorage-independent colonies, which were all significantly reduced. Supplementation with MDA-MB-231 derived exosomes restored the ability to form colonies, suggesting exosomes may contribute to metastatic lesion formation. These data suggest that the exosomal pathway is a valid target to disrupt the behaviour of tumour cells and NTA can be used to monitor its activity.Stiffness: a key mechanical factor in normal, degenerate and artificial lumbar intervertebral discsRoss, Edward R. S.https://hdl.handle.net/10023/32132019-04-01T08:53:11Z2012-11-30T00:00:00ZThis thesis describes the development of artificial disc technology for the replacement of intervertebral discs in the human lumbar spine. The clinical
problem is back pain. There may be a relationship between certain forms of
back pain and disc degeneration. The mechanical properties of human intervertebral discs are examined in detail. The genetic basis of disc degeneration is
presented. The hypothesis is that such degeneration leads to a loss of normal
stiffness in the segments affected leading to abnormal mechanical behaviour
which in turn leads to pain. The evidence for this is presented. The development of surgical solutions to relieve back pain, from fusion through first
generation mechanical artificial discs to elastomeric designs, is traced. The
author‘s personal contributions to this area of knowledge are set out. The
appreciation of the requirement for a restoration of physiological stiffness is
argued throughout, showing where fusion and first generation discs have not
met the clinical aim of pain relief, because they have not restored physiological stiffness. The path to an elastomeric, viscoelastic, polyhydrocarbon, rubber
solution in the form of the “Freedom“ disc has filled 17 years of the author‘s
academic pursuits. It will be shown that this technology may represent a possible solution to the clinical problem. Failure is part of all new advancement
and this too is presented, to show how that has influenced thinking, producing
original ideas to overcome these failures. Providing lessons are learned from
these failures then our patients in the future will benefit.
2012-11-30T00:00:00ZRoss, Edward R. S.This thesis describes the development of artificial disc technology for the replacement of intervertebral discs in the human lumbar spine. The clinical
problem is back pain. There may be a relationship between certain forms of
back pain and disc degeneration. The mechanical properties of human intervertebral discs are examined in detail. The genetic basis of disc degeneration is
presented. The hypothesis is that such degeneration leads to a loss of normal
stiffness in the segments affected leading to abnormal mechanical behaviour
which in turn leads to pain. The evidence for this is presented. The development of surgical solutions to relieve back pain, from fusion through first
generation mechanical artificial discs to elastomeric designs, is traced. The
author‘s personal contributions to this area of knowledge are set out. The
appreciation of the requirement for a restoration of physiological stiffness is
argued throughout, showing where fusion and first generation discs have not
met the clinical aim of pain relief, because they have not restored physiological stiffness. The path to an elastomeric, viscoelastic, polyhydrocarbon, rubber
solution in the form of the “Freedom“ disc has filled 17 years of the author‘s
academic pursuits. It will be shown that this technology may represent a possible solution to the clinical problem. Failure is part of all new advancement
and this too is presented, to show how that has influenced thinking, producing
original ideas to overcome these failures. Providing lessons are learned from
these failures then our patients in the future will benefit.The role of ChlR1 in DNA replication, DNA damage repair and cohesion establishmentWasson, Christopherhttps://hdl.handle.net/10023/31342019-04-01T08:52:42Z2011-01-01T00:00:00ZSister chromatid cohesion is essential for the equal distribution of genetic material in
mitosis. The cohesin complex plays a central role in the establishment of sister chromatid
cohesion. The cohesin complex is a ring shaped structure that encircles sister chromatids
prior to the onset of anaphase ensuring equal distribution of genetic material. The
DEAD/H DNA helicase ChlR1 is important in the establishment of sister chromatid
cohesion. ChlR1 interacts with the cohesin complex and is required for the loading of
cohesin onto DNA. Cohesin is loaded onto the DNA during DNA replication.
Here I identified a novel interacting partner of ChlR1. The multifunctional DNA binding
protein FHL2 was shown to interact with ChlR1, and FHL2 was shown to have a role in
sister chromatid cohesion since depletion of FHL2 resulted in abnormal metaphase spreads
and reduced centromeric cohesion. These sister chromatid cohesion defects also result in a
G₂/M delay.
Here I show an additional function of ChlR1 in the repair of DNA damage. ChlR1 was
required for the repair of DNA double strand breaks and ChlR1 was recruited to DNA
double strand breaks. Furthermore the function of ChlR1 in DNA double strand break
repair is S phase specific. This suggests that ChlR1 is important in the homology
recombination repair pathway. I also show that ChlR1 is important in DNA replication. Depletion of ChlR1 results in
inefficient DNA replication. In addition depletion of ChlR1 results in defects in DNA
replication after hydroxyurea treatment.
The results in this thesis shed light on novel functions of the DNA helicase ChlR1 in DNA
replication and DNA damage repair and the multifunctional DNA binding protein FHL2 in
cohesion establishment.
2011-01-01T00:00:00ZWasson, ChristopherSister chromatid cohesion is essential for the equal distribution of genetic material in
mitosis. The cohesin complex plays a central role in the establishment of sister chromatid
cohesion. The cohesin complex is a ring shaped structure that encircles sister chromatids
prior to the onset of anaphase ensuring equal distribution of genetic material. The
DEAD/H DNA helicase ChlR1 is important in the establishment of sister chromatid
cohesion. ChlR1 interacts with the cohesin complex and is required for the loading of
cohesin onto DNA. Cohesin is loaded onto the DNA during DNA replication.
Here I identified a novel interacting partner of ChlR1. The multifunctional DNA binding
protein FHL2 was shown to interact with ChlR1, and FHL2 was shown to have a role in
sister chromatid cohesion since depletion of FHL2 resulted in abnormal metaphase spreads
and reduced centromeric cohesion. These sister chromatid cohesion defects also result in a
G₂/M delay.
Here I show an additional function of ChlR1 in the repair of DNA damage. ChlR1 was
required for the repair of DNA double strand breaks and ChlR1 was recruited to DNA
double strand breaks. Furthermore the function of ChlR1 in DNA double strand break
repair is S phase specific. This suggests that ChlR1 is important in the homology
recombination repair pathway. I also show that ChlR1 is important in DNA replication. Depletion of ChlR1 results in
inefficient DNA replication. In addition depletion of ChlR1 results in defects in DNA
replication after hydroxyurea treatment.
The results in this thesis shed light on novel functions of the DNA helicase ChlR1 in DNA
replication and DNA damage repair and the multifunctional DNA binding protein FHL2 in
cohesion establishment.TOX3 : a candidate breast cancer predisposition geneSchmidt, Xeniahttps://hdl.handle.net/10023/31042020-02-20T11:59:40Z2012-06-01T00:00:00Z2012-06-01T00:00:00ZSchmidt, XeniaWilliam Pulteney Alison : activist philanthropist and pioneer of social medicineMartin, Sheonagh M. K.https://hdl.handle.net/10023/28152019-08-26T11:19:30Z1997-01-01T00:00:00ZThe thesis looks in detail at three inter-related aspects of
Alison's life. It examines, firstly, his role in the development
of Edinburgh's rudimentary 'health' network, achieved through the
expansion of the existing medical charity structure and the
introduction of a more interventionist and coordinated approach to
the city's health problems. It traces, secondly, the development
of Alison's social thought - in 1820 he believed that medical and
practical relief for the poor could and should be supplied through
the voluntary charities and only when that proved unsatisfactory
through the poor law, whereas by 1840 he argued that public health
should be the responsibility of government and that the excessive
increase in poverty and disease in Scotland, which he believed had
occurred, was proof that the charitable and legal relief provided
was inadequate. Finally, Alison's influence on the passage of
Scottish poor law and public health legislation in the 1840s and
1850s is examined - the latter involving an assessment of how far
he was responsible for the legislative delay. The poor law debate,
1840-1845, which reveals the forces shaping the reform and the
prevailing attitudes to poverty, highlights the challenge which
Alison's opinions represented and the resulting turmoil in Scottish
social thinking, while his reasons for opposing health legislation,
which established London control are of great importance. They
reveal differences in the rationale behind, and way in which, the
concept of public health was developed in Scotland and England.
Unlike Chadwick and his supporters, Alison emphasised poverty
amelioration and sanitary reform. Part of the explanation for the
differing opinions lay in their respective miasmatic and
contagionist theories for fever generation, but it also reflects,
perhaps more significantly, the impact of European medical police
ideas on Scottish medical opinion - Alison's view of public health
closely resembled that of the French hygienists.
1997-01-01T00:00:00ZMartin, Sheonagh M. K.The thesis looks in detail at three inter-related aspects of
Alison's life. It examines, firstly, his role in the development
of Edinburgh's rudimentary 'health' network, achieved through the
expansion of the existing medical charity structure and the
introduction of a more interventionist and coordinated approach to
the city's health problems. It traces, secondly, the development
of Alison's social thought - in 1820 he believed that medical and
practical relief for the poor could and should be supplied through
the voluntary charities and only when that proved unsatisfactory
through the poor law, whereas by 1840 he argued that public health
should be the responsibility of government and that the excessive
increase in poverty and disease in Scotland, which he believed had
occurred, was proof that the charitable and legal relief provided
was inadequate. Finally, Alison's influence on the passage of
Scottish poor law and public health legislation in the 1840s and
1850s is examined - the latter involving an assessment of how far
he was responsible for the legislative delay. The poor law debate,
1840-1845, which reveals the forces shaping the reform and the
prevailing attitudes to poverty, highlights the challenge which
Alison's opinions represented and the resulting turmoil in Scottish
social thinking, while his reasons for opposing health legislation,
which established London control are of great importance. They
reveal differences in the rationale behind, and way in which, the
concept of public health was developed in Scotland and England.
Unlike Chadwick and his supporters, Alison emphasised poverty
amelioration and sanitary reform. Part of the explanation for the
differing opinions lay in their respective miasmatic and
contagionist theories for fever generation, but it also reflects,
perhaps more significantly, the impact of European medical police
ideas on Scottish medical opinion - Alison's view of public health
closely resembled that of the French hygienists.Quality of care for people with mental handicap and challenging behaviour : an investigation of the impact of staff training in goal attainment scaling and behavioural proceduresTurnbull, Johnhttps://hdl.handle.net/10023/28072019-04-01T08:53:33Z1992-01-01T00:00:00ZThis study examined the contribution to quality of care
of a goal planning technique called Goal Attainment
Scaling and its impact upon the quality of life of people
with severe mental handicaps and challenging behaviour.
The study also seeks to establish the utility of
employing Goal Attainment Scaling as a means of
evaluating clinical nursing performance,
This study essentially aims to bring about changes in the
care practices of nurses using a comprehensive staff
management procedure. The study was designed as a four
phase intervention using a multiple baseline design
across three wards in a hospital for people with mental
handicaps. Staff on three wards (n = 41) were initially
trained over three phases in the use of Goal Attainment
Scaling and other procedures. Training was carried out by
a combination of workshops and individual tuition which
incorporated the use of individualised learning contracts
for staff. The fourth phase consisted of establishing
weekly meetings to set objectives for staff to achieve
that were specifically related to material covered in
training. If targets were achieved, staff performance was
followed by letters of recognition from managers and by
financial donations to ward funds.
Dependent measures included frequency of challenging
behaviour, quality of staff-resident interaction and
engagement, ward activity, residents' adaptive behaviour,
staff attitudes and goals set by staff. Results indicate
that adaptive behaviour increased by small but
statistically significant levels. Levels of challenging
display a mixed pattern of results, as do levels of ward
activity and quality of interaction, although encouraging
trends may be identified. Despite some increases,
residents still spend significant amounts of time
unoccupied. The number of goals set increased throughout
the study, particularly in phase four, data for staff
attitudes were not used because of the low compliance
rate and changes indicated below.
Considerable problems were encountered with turnover of
staff and other organisational changes outwith the
researcher's control which compromised both the quality
of training given to staff and, by virtue of this, the
final results. Statistically significant relationships
were found to exist between staff turnover and
interaction.
The implications of this study are discussed and
recommendations made for future research.
1992-01-01T00:00:00ZTurnbull, JohnThis study examined the contribution to quality of care
of a goal planning technique called Goal Attainment
Scaling and its impact upon the quality of life of people
with severe mental handicaps and challenging behaviour.
The study also seeks to establish the utility of
employing Goal Attainment Scaling as a means of
evaluating clinical nursing performance,
This study essentially aims to bring about changes in the
care practices of nurses using a comprehensive staff
management procedure. The study was designed as a four
phase intervention using a multiple baseline design
across three wards in a hospital for people with mental
handicaps. Staff on three wards (n = 41) were initially
trained over three phases in the use of Goal Attainment
Scaling and other procedures. Training was carried out by
a combination of workshops and individual tuition which
incorporated the use of individualised learning contracts
for staff. The fourth phase consisted of establishing
weekly meetings to set objectives for staff to achieve
that were specifically related to material covered in
training. If targets were achieved, staff performance was
followed by letters of recognition from managers and by
financial donations to ward funds.
Dependent measures included frequency of challenging
behaviour, quality of staff-resident interaction and
engagement, ward activity, residents' adaptive behaviour,
staff attitudes and goals set by staff. Results indicate
that adaptive behaviour increased by small but
statistically significant levels. Levels of challenging
display a mixed pattern of results, as do levels of ward
activity and quality of interaction, although encouraging
trends may be identified. Despite some increases,
residents still spend significant amounts of time
unoccupied. The number of goals set increased throughout
the study, particularly in phase four, data for staff
attitudes were not used because of the low compliance
rate and changes indicated below.
Considerable problems were encountered with turnover of
staff and other organisational changes outwith the
researcher's control which compromised both the quality
of training given to staff and, by virtue of this, the
final results. Statistically significant relationships
were found to exist between staff turnover and
interaction.
The implications of this study are discussed and
recommendations made for future research.Health professionals and ethnic Pakistanis in Britain : risk, thalassaemia and audit cultureMurphy, Richardhttps://hdl.handle.net/10023/28022019-04-01T08:53:36Z2005-01-01T00:00:00ZThe
central theme or
'red-thread' that I
consider
in this thesis is the concept of risk as it is
perceived
by
and affects the two sides of
the medical encounter
-in this instance
ethnic
Pakistanis
and
Health Professionals-
in Britain. Each
side very often perceives risk quite
distinctively,
relating to the balance between the spiritual and temporal realms.
This is
particularly germane
in
matters to do
with possible congenital
defects
within the prenatal
realm
for the ethnic
Pakistani,
and predominantly
Muslim,
side of this encounter.
Thus
one
of the factors
considered
in this thesis is how
senses of
Islam impact
upon the two sides.
By
ethnic
Pakistanis Islam is
seen as central to all
life decisions,
whilst
Health Professionals
view
Islam
with some considerable trepidation, little
understanding
it
or
its
centrality to the
former's decision-making
processes. This is
particularly significant with regard to attitudes
to health
and
health
care.
In the initial
stages of the project
I had thought first
cousin
marriage
(FCM),
seen by
ethnic
Pakistanis
as desirable
and
by Health Professionals
as
putting ethnic
Pakistanis
at-risk to be
central to the argument,
but
concluded that concerns
around
FCM
were a
'red herring',
merely a trope for the tensions between the two sides -at
once
both British
and at-risk
from
audit culture.
Although
no
longer
central,
FCM
remains a
viable touchstone in
consideration of the two sides' perceptions of genetic risk.
In this thesis
the medical encounter
between
ethnic
Pakistanis
and
Health Professionals is
performed
within the realm of the so called
New Genetics. Here the respective understandings of the
New Genetics
are
informed by the enculturation processes that shape the two sides' world
view.
Furthermore, I
will agree with
Lord Robert Winston's
and others' concern that any
attempt
to eradicate an adaptive genetic mutation,
in this instance, thalassaemia, from the
gene pool
is
not only undesirable
in the short term, but
also that such eradications may
have
an adverse, and
far
reaching, effect on whole population groups
in the future. The
main
thrust of my argument
is that audit culture not only compounds risk
for both
sides,
but
also
perpetuates institutional
racism within the National Health Service (NHS), by
promulgating
what
I have
called the language
myth.
That is to say that much
institutional
racism
is the
unwanted
by-product
of the NHS's
attempts to become
more patient centred and
its
continuing efforts to develop
systems of
best practice.
This
professionalisation process
within
the NHS
can
be
seen to impact
most strongly
in
relation to communication
-particularly the claimed
language barrier between the two sides.
This 'barrier' has worrying
policy
implications for
any meaningful communication
between the two sides, notably
relating to obtaining
informed
consent
from
ethnic
Pakistani
patients
-with a resultant
increase in
risk
for
the two sides and clear economic consequences for the NHS.
2005-01-01T00:00:00ZMurphy, RichardThe
central theme or
'red-thread' that I
consider
in this thesis is the concept of risk as it is
perceived
by
and affects the two sides of
the medical encounter
-in this instance
ethnic
Pakistanis
and
Health Professionals-
in Britain. Each
side very often perceives risk quite
distinctively,
relating to the balance between the spiritual and temporal realms.
This is
particularly germane
in
matters to do
with possible congenital
defects
within the prenatal
realm
for the ethnic
Pakistani,
and predominantly
Muslim,
side of this encounter.
Thus
one
of the factors
considered
in this thesis is how
senses of
Islam impact
upon the two sides.
By
ethnic
Pakistanis Islam is
seen as central to all
life decisions,
whilst
Health Professionals
view
Islam
with some considerable trepidation, little
understanding
it
or
its
centrality to the
former's decision-making
processes. This is
particularly significant with regard to attitudes
to health
and
health
care.
In the initial
stages of the project
I had thought first
cousin
marriage
(FCM),
seen by
ethnic
Pakistanis
as desirable
and
by Health Professionals
as
putting ethnic
Pakistanis
at-risk to be
central to the argument,
but
concluded that concerns
around
FCM
were a
'red herring',
merely a trope for the tensions between the two sides -at
once
both British
and at-risk
from
audit culture.
Although
no
longer
central,
FCM
remains a
viable touchstone in
consideration of the two sides' perceptions of genetic risk.
In this thesis
the medical encounter
between
ethnic
Pakistanis
and
Health Professionals is
performed
within the realm of the so called
New Genetics. Here the respective understandings of the
New Genetics
are
informed by the enculturation processes that shape the two sides' world
view.
Furthermore, I
will agree with
Lord Robert Winston's
and others' concern that any
attempt
to eradicate an adaptive genetic mutation,
in this instance, thalassaemia, from the
gene pool
is
not only undesirable
in the short term, but
also that such eradications may
have
an adverse, and
far
reaching, effect on whole population groups
in the future. The
main
thrust of my argument
is that audit culture not only compounds risk
for both
sides,
but
also
perpetuates institutional
racism within the National Health Service (NHS), by
promulgating
what
I have
called the language
myth.
That is to say that much
institutional
racism
is the
unwanted
by-product
of the NHS's
attempts to become
more patient centred and
its
continuing efforts to develop
systems of
best practice.
This
professionalisation process
within
the NHS
can
be
seen to impact
most strongly
in
relation to communication
-particularly the claimed
language barrier between the two sides.
This 'barrier' has worrying
policy
implications for
any meaningful communication
between the two sides, notably
relating to obtaining
informed
consent
from
ethnic
Pakistani
patients
-with a resultant
increase in
risk
for
the two sides and clear economic consequences for the NHS.Coping with asthma : investigation and intervention using the self-regulation modelWilliams, Julie M.https://hdl.handle.net/10023/28002019-07-01T10:06:07Z1995-01-01T00:00:00ZThe Self-Regulation Model (Leventhal, Nerenz & Steele, 1984)
highlights the roles of patients' illness representations, coping, emotional
reactions and appraisal of coping in the progression of chronic disease. This
thesis incorporates previous literature on adherence, panic-fear and selfmanagement
interventions into the model in order to (a) investigate coping
with asthma and (b) develop an intervention aimed at improving asthmatic
control.
New measures of asthmatic control and illness representations of the
consequences of having asthma were developed in order to operationalise the
model.
A cross-sectional study investigated factors influencing asthmatic
control in a sample of 35 adult asthma sufferers recruited through a single
general practice. Coping was poor, adherence being low and less than 50% of
participants reporting current Peak Flow monitoring or medical contact
during the previous 12 months. Good coping appeared to be a response to
poor asthmatic control, rather than prophylactic. Good asthmatic control was
associated with low perceived consequences, recent medical contact, moderate
panic-fear and low general avoidance coping. These results imply that
asthmatic control may be improved by encouraging sufferers to maintain
regular contact with outpatient services and to implement prophylactic
coping.
Since epidemiological and clinical evidence suggested asthmatic
control to be poor in young adults, an intervention was developed to
improve asthmatic control in this group by modifying illness representations,
coping and panic-fear. The intervention was evaluated in a randomised
controlled study of 50 student asthma sufferers identified initially through an
epidemiological screening of 2,979 students. It led to increased Preventer
medication use and Peak Flow monitoring and decreased distress over the
condition. However, the coping process changed and asthmatic control
improved even in the control group, perhaps because self-monitoring of
asthmatic control for the study constituted a change in coping. This
unanticipated result was entirely compatible with the Self-Regulation Model.
The thesis dearly demonstrates value of the Self-Regulation Model in
understanding asthma self-management and developing clinical
interventions.
1995-01-01T00:00:00ZWilliams, Julie M.The Self-Regulation Model (Leventhal, Nerenz & Steele, 1984)
highlights the roles of patients' illness representations, coping, emotional
reactions and appraisal of coping in the progression of chronic disease. This
thesis incorporates previous literature on adherence, panic-fear and selfmanagement
interventions into the model in order to (a) investigate coping
with asthma and (b) develop an intervention aimed at improving asthmatic
control.
New measures of asthmatic control and illness representations of the
consequences of having asthma were developed in order to operationalise the
model.
A cross-sectional study investigated factors influencing asthmatic
control in a sample of 35 adult asthma sufferers recruited through a single
general practice. Coping was poor, adherence being low and less than 50% of
participants reporting current Peak Flow monitoring or medical contact
during the previous 12 months. Good coping appeared to be a response to
poor asthmatic control, rather than prophylactic. Good asthmatic control was
associated with low perceived consequences, recent medical contact, moderate
panic-fear and low general avoidance coping. These results imply that
asthmatic control may be improved by encouraging sufferers to maintain
regular contact with outpatient services and to implement prophylactic
coping.
Since epidemiological and clinical evidence suggested asthmatic
control to be poor in young adults, an intervention was developed to
improve asthmatic control in this group by modifying illness representations,
coping and panic-fear. The intervention was evaluated in a randomised
controlled study of 50 student asthma sufferers identified initially through an
epidemiological screening of 2,979 students. It led to increased Preventer
medication use and Peak Flow monitoring and decreased distress over the
condition. However, the coping process changed and asthmatic control
improved even in the control group, perhaps because self-monitoring of
asthmatic control for the study constituted a change in coping. This
unanticipated result was entirely compatible with the Self-Regulation Model.
The thesis dearly demonstrates value of the Self-Regulation Model in
understanding asthma self-management and developing clinical
interventions.The regulation of haemopoietic stem cell and progenitor cell proliferation by humoral factorsCork, Michael Johnhttps://hdl.handle.net/10023/27202019-04-01T08:53:19Z1984-01-01T00:00:00ZThe mechanisms which regulate the growth fraction of the
haemopoietic stem cell (CFU-S) and granulocyte macrophage
progenitor cell (GM-CFC) have been investigated. In normal murine
bone marrow (NMBM) a small proportion of the CFU-S are synthesising
DNA (-10%). In contrast, in the bone marrow from mice regenerating
after treatment with cytotoxic drugs and in developing haemopoietic
tissues such as murine fetal liver a large proportion of the CFU-S
(-40%) are synthesising DNA. Medium conditioned by normal murine
and human bone marrow cells inhibited the proliferation of rapidly
cycling CFU-S from regenerating bone marrow. This inhibitor was
contained in a 50-100K daltons ultrafiltration fraction. In
contra-distinction medium conditioned by human fetal liver cells
stimulated the proliferation of CFU-S from NMBM. The stimulator
was produced by adherent cells and was contained in a 30-50K
daltons ultrafiltration fraction.
An alternative assay for the humoral regulators of CFU-S
proliferation was developed. Different numbers of haemopoietic
cells were injected into lethally irradiated mice. Five days later
they were injected with 2iCi of
125IUdR
and sacrificed 2 hours
later. There was a linear relationship between the log 125IUdR
uptake into the spleen and femur and the log cell dose injected.
Pre-treatment of haemopoietic cells with an S-phase specific
cytotoxic drug resulted in a reduction in the
125IUdR
incorporation
into the spleen. This enabled the kinetic properties of a
haemopoietic stem cell population to be assessed and the humoral
111
factors which modulate the growth fraction of these cells to be
investigated.
At early stages of gestation (11-14 weeks) in human fetal
liver few GM-CFC are synthesising DNA, whereas later in gestation
(>14 weeks) a large proportion of GM-CFC are in S-phase, Moore and
Williams (1973b). Incubation of NMBM GM-CFC (approx 40% in DNA
synthesis) with a supernatant from an early human fetal liver
(11-14 weeks) reduced the proportion synthesising DNA to <5%. In
contrast, the proportion of murine GM-CFC synthesising DNA was not
affected by incubation with a supernatant from a late human fetal
liver (>14 weeks). GM-CFC that had been switched out of cycle by
incubation with a supernatant from an early gestation human fetal
liver were switched back into cycle following incubation with a
late human fetal liver supernatant. The inhibitor and stimulator
of GM-CFC proliferation were both produced by non-adherent cells
and were contained in >100K and 30-50K daltons ultrafiltration
fractions repectively. It is likely that changes in the relative
levels of a proliferation inhibitor and stimulator throughout
gestation might control the proportion of GM-CFC in cycle.
1984-01-01T00:00:00ZCork, Michael JohnThe mechanisms which regulate the growth fraction of the
haemopoietic stem cell (CFU-S) and granulocyte macrophage
progenitor cell (GM-CFC) have been investigated. In normal murine
bone marrow (NMBM) a small proportion of the CFU-S are synthesising
DNA (-10%). In contrast, in the bone marrow from mice regenerating
after treatment with cytotoxic drugs and in developing haemopoietic
tissues such as murine fetal liver a large proportion of the CFU-S
(-40%) are synthesising DNA. Medium conditioned by normal murine
and human bone marrow cells inhibited the proliferation of rapidly
cycling CFU-S from regenerating bone marrow. This inhibitor was
contained in a 50-100K daltons ultrafiltration fraction. In
contra-distinction medium conditioned by human fetal liver cells
stimulated the proliferation of CFU-S from NMBM. The stimulator
was produced by adherent cells and was contained in a 30-50K
daltons ultrafiltration fraction.
An alternative assay for the humoral regulators of CFU-S
proliferation was developed. Different numbers of haemopoietic
cells were injected into lethally irradiated mice. Five days later
they were injected with 2iCi of
125IUdR
and sacrificed 2 hours
later. There was a linear relationship between the log 125IUdR
uptake into the spleen and femur and the log cell dose injected.
Pre-treatment of haemopoietic cells with an S-phase specific
cytotoxic drug resulted in a reduction in the
125IUdR
incorporation
into the spleen. This enabled the kinetic properties of a
haemopoietic stem cell population to be assessed and the humoral
111
factors which modulate the growth fraction of these cells to be
investigated.
At early stages of gestation (11-14 weeks) in human fetal
liver few GM-CFC are synthesising DNA, whereas later in gestation
(>14 weeks) a large proportion of GM-CFC are in S-phase, Moore and
Williams (1973b). Incubation of NMBM GM-CFC (approx 40% in DNA
synthesis) with a supernatant from an early human fetal liver
(11-14 weeks) reduced the proportion synthesising DNA to <5%. In
contrast, the proportion of murine GM-CFC synthesising DNA was not
affected by incubation with a supernatant from a late human fetal
liver (>14 weeks). GM-CFC that had been switched out of cycle by
incubation with a supernatant from an early gestation human fetal
liver were switched back into cycle following incubation with a
late human fetal liver supernatant. The inhibitor and stimulator
of GM-CFC proliferation were both produced by non-adherent cells
and were contained in >100K and 30-50K daltons ultrafiltration
fractions repectively. It is likely that changes in the relative
levels of a proliferation inhibitor and stimulator throughout
gestation might control the proportion of GM-CFC in cycle.Defining a role for the peduncolopontine tegmental nucleus in striatal outflowAllen, Laura F.https://hdl.handle.net/10023/26732019-04-01T08:53:32Z1996-01-01T00:00:00ZThe pedunculopontine tegmental nucleus (PPTg) lies within the pontomesencephalon
and contains cholinergic and non-cholinergic neurones. It has extensive afferent and
efferent connections throughout the brain. Early research suggested a role for the
PPTg in the mediation of locomotor activity, and it was believed to form the major
substrate of the electrophysiologically identified mesencephalic locomotor region
(rviLR). Studies using selective excitotoxic lesions of the PPTg demonstrated that it
has no role in the mediation of spontaneous or nucleus accumbens-induced (NAcc)
locomotion. However evidence has suggested that the cuneiform nucleus (CNF) and
not the PPTg is the main locus of the .MLR. The effects of bilateral ibotenate CNF
lesions on spontaneous and amphetamine-induced locomotion stimulated from the
NAcc were therefore investigated. CNF lesions had no effect on either type of
locomotor activity.
Bilateral ibotenate lesions of the PPTg have been shown to influence the
expression of orofacial stereotypies following administration of systemic
amphetamine. Oral stereotypies can be elicited reliably by direct stimulation of the
ventrolateral caudate-putamen (VLCP). This thesis sought to clarify the role of the
PPTg in the mediation of oral stereotypies, by combining bilateral ibotenate lesions of
the PPTg with direct microinjection of amphetamine into the VLCP. Lesions of the
PPTg caused a shift in the dose response curve to amphetamine resulting in an
increase in the incidence and intensity of oro facial stereotypies at lower doses. Thus
the PPTg appears to have inhibitory control over the expression of orofacial
behaviors.
It is hypothesised that while neither the PPTg nor the CNF have a role in the
mediation of locomotor activity per se they may provide an integrative functional
role, which influences motor outflow. The role of the CNF in the transmission of
nociception and a role for the PPTg in the mediation of striatal outflow is discussed.
1996-01-01T00:00:00ZAllen, Laura F.The pedunculopontine tegmental nucleus (PPTg) lies within the pontomesencephalon
and contains cholinergic and non-cholinergic neurones. It has extensive afferent and
efferent connections throughout the brain. Early research suggested a role for the
PPTg in the mediation of locomotor activity, and it was believed to form the major
substrate of the electrophysiologically identified mesencephalic locomotor region
(rviLR). Studies using selective excitotoxic lesions of the PPTg demonstrated that it
has no role in the mediation of spontaneous or nucleus accumbens-induced (NAcc)
locomotion. However evidence has suggested that the cuneiform nucleus (CNF) and
not the PPTg is the main locus of the .MLR. The effects of bilateral ibotenate CNF
lesions on spontaneous and amphetamine-induced locomotion stimulated from the
NAcc were therefore investigated. CNF lesions had no effect on either type of
locomotor activity.
Bilateral ibotenate lesions of the PPTg have been shown to influence the
expression of orofacial stereotypies following administration of systemic
amphetamine. Oral stereotypies can be elicited reliably by direct stimulation of the
ventrolateral caudate-putamen (VLCP). This thesis sought to clarify the role of the
PPTg in the mediation of oral stereotypies, by combining bilateral ibotenate lesions of
the PPTg with direct microinjection of amphetamine into the VLCP. Lesions of the
PPTg caused a shift in the dose response curve to amphetamine resulting in an
increase in the incidence and intensity of oro facial stereotypies at lower doses. Thus
the PPTg appears to have inhibitory control over the expression of orofacial
behaviors.
It is hypothesised that while neither the PPTg nor the CNF have a role in the
mediation of locomotor activity per se they may provide an integrative functional
role, which influences motor outflow. The role of the CNF in the transmission of
nociception and a role for the PPTg in the mediation of striatal outflow is discussed.Physical activity and perceived benefits and barriers in adults aged 55-74Montgomery, Alan A.https://hdl.handle.net/10023/26632019-04-01T08:53:26Z1997-01-01T00:00:00ZIn order to increase the number of older adults physically active enough to
obtain the health benefits of exercise, inactive individuals must firstly be
identified, and attention must then be focused on determinants of exercise
amenable to change.
This study set out to develop self-complete questionnaires for assessing activity
status, and perceived benefits of, and barriers to, physical activity.
Of 1456 questionnaires sent out to a random sample of adults aged 55-74 a
usable return rate of 37.6% (n=548) was achieved. A principal components
analysis of the benefits of physical activity revealed five factors (physical
performance, social, weight control, enjoyment, and psychological), and of the
barriers to physical activity, also five factors (opportunities, physical exertion,
time, limiting health, and support). Alpha internal consistency coefficients for
the 10 factors ranged from 0.64 to 0.92, and test-retest reliability coefficients
from 0.56 to 0.87. A series of one-way ANOVAs revealed that, with the
exception of the benefit weight control, there was a significant gradation in
factor scores between active and inactive subjects as classified by 4-, 9-, and 5-
point activity classification methods.
Validity of the activity classifications was assessed in a subsample of 86
subjects against measures of strength, flexibility, aerobic fitness and objectively
measured physical activity. Active and inactive subjects classified using the 4-
and 9-point questionnaires differed significantly in 1-mile walk time and energy
expenditure estimated by a Caltrac accelerometer. The 5-point questionnaire did
not appear able to differentiate active and inactive subjects. Test-retest reliability
of the questionnaires ranged from 0.62 to 0.73.
The questionnaire developed from this work for measuring perceived benefits
and barriers of older adults can be used in either practical or research settings.
Further work is required to determine the accuracy of the physical activity
questionnaires in identifying low-active individuals in the population.
1997-01-01T00:00:00ZMontgomery, Alan A.In order to increase the number of older adults physically active enough to
obtain the health benefits of exercise, inactive individuals must firstly be
identified, and attention must then be focused on determinants of exercise
amenable to change.
This study set out to develop self-complete questionnaires for assessing activity
status, and perceived benefits of, and barriers to, physical activity.
Of 1456 questionnaires sent out to a random sample of adults aged 55-74 a
usable return rate of 37.6% (n=548) was achieved. A principal components
analysis of the benefits of physical activity revealed five factors (physical
performance, social, weight control, enjoyment, and psychological), and of the
barriers to physical activity, also five factors (opportunities, physical exertion,
time, limiting health, and support). Alpha internal consistency coefficients for
the 10 factors ranged from 0.64 to 0.92, and test-retest reliability coefficients
from 0.56 to 0.87. A series of one-way ANOVAs revealed that, with the
exception of the benefit weight control, there was a significant gradation in
factor scores between active and inactive subjects as classified by 4-, 9-, and 5-
point activity classification methods.
Validity of the activity classifications was assessed in a subsample of 86
subjects against measures of strength, flexibility, aerobic fitness and objectively
measured physical activity. Active and inactive subjects classified using the 4-
and 9-point questionnaires differed significantly in 1-mile walk time and energy
expenditure estimated by a Caltrac accelerometer. The 5-point questionnaire did
not appear able to differentiate active and inactive subjects. Test-retest reliability
of the questionnaires ranged from 0.62 to 0.73.
The questionnaire developed from this work for measuring perceived benefits
and barriers of older adults can be used in either practical or research settings.
Further work is required to determine the accuracy of the physical activity
questionnaires in identifying low-active individuals in the population.The effects of leptomycin B on HPV-infected cellsJolly, Carol Ehttps://hdl.handle.net/10023/9002019-07-01T10:15:13Z2008-01-01T00:00:00ZCervical cancer is a major cause of death in women and is strongly associated with infection by human papillomavirus (HPV). Integration of HPV is thought to form a key step in the formation of cancer, and is thought to involve the upregulation of HPV E6 and E7 due to the loss of E2 transcriptional control. Leptomycin B (LMB), a nuclear export inhibitor, has previously been shown to induce apoptosis in HPV-containing cancer cell lines and HPV 16 E7 or E6/E7 transduced primary keratinocytes, but not in normal cells. This thesis shows that LMB can induce apoptosis and a reduction in the colony survival of derivatives of the W12 cell line that contain HPV 16 in either episomal or integrated form. The HPV genome status, including variations in viral integration type, appears to influence the cumulative and temporal pattern of LMB-induced apoptosis. The effects of LMB were also apparent in cells grown in organotypic raft culture, with differences in behaviour again apparent between cells containing episomal and integrated HPV. As previously noted, treatment with LMB was associated with increased expression of the cell regulators p53 and p21; however, the induction of apoptosis was not dependent upon transcriptionally active p53. It is therefore likely that induction and mediation of LMB-induced apoptosis occurs via alternative, currently unidentified, pathways. These findings suggest that LMB can induce apoptosis in keratinocytes containing HPV 16 in either episomal or integrated form, with genome status and potentially lesion grade likely to influence the response of HPV-associated anogenital lesions to LMB treatment.
2008-01-01T00:00:00ZJolly, Carol ECervical cancer is a major cause of death in women and is strongly associated with infection by human papillomavirus (HPV). Integration of HPV is thought to form a key step in the formation of cancer, and is thought to involve the upregulation of HPV E6 and E7 due to the loss of E2 transcriptional control. Leptomycin B (LMB), a nuclear export inhibitor, has previously been shown to induce apoptosis in HPV-containing cancer cell lines and HPV 16 E7 or E6/E7 transduced primary keratinocytes, but not in normal cells. This thesis shows that LMB can induce apoptosis and a reduction in the colony survival of derivatives of the W12 cell line that contain HPV 16 in either episomal or integrated form. The HPV genome status, including variations in viral integration type, appears to influence the cumulative and temporal pattern of LMB-induced apoptosis. The effects of LMB were also apparent in cells grown in organotypic raft culture, with differences in behaviour again apparent between cells containing episomal and integrated HPV. As previously noted, treatment with LMB was associated with increased expression of the cell regulators p53 and p21; however, the induction of apoptosis was not dependent upon transcriptionally active p53. It is therefore likely that induction and mediation of LMB-induced apoptosis occurs via alternative, currently unidentified, pathways. These findings suggest that LMB can induce apoptosis in keratinocytes containing HPV 16 in either episomal or integrated form, with genome status and potentially lesion grade likely to influence the response of HPV-associated anogenital lesions to LMB treatment.A role for topoisomerase II alpha in chromosome damage in human cell linesTerry, Samantha Y.A.https://hdl.handle.net/10023/8732019-07-01T10:05:52Z2010-06-01T00:00:00ZHuman response to ionising radiation (IR) shows a wide variation. This is most clearly seen in
the radiation-response of cells as measured by frequencies of chromosomal aberrations.
Different frequencies of IR-induced aberrations can be conveniently observed in
phytohaemagglutin-stimulated peripheral blood T-lymphocytes from both normal individuals
and sporadic cancer cases, in either metaphase chromosomes or as micronuclei in the
following cell cycle. Metaphase cells show frequent chromatid breaks, defined as chromatid
discontinuities or terminal deletions, if irradiated in the G 2 -phase of the cell cycle. It has been
shown that the frequency of chromatid breaks in cells from approximately 40% of sporadic
breast cancer patients, are significantly higher than in groups of normal individuals. This
suggests that elevated radiation-induced chromatid break frequency may be linked with
susceptibility to breast cancer.
It is known that chromatid breaks are initiated by a double strand break (DSB), but it appears
that the two are linked only indirectly as repair kinetics for DSBs and chromatid breaks do not
match. Therefore, the underlying causes of the wide variation in frequencies of chromatid
breaks in irradiated T-lymphocytes from different normal individuals and from sporadic breast
cancer cases are still unclear but it is unlikely to be linked directly to DSB rejoining.
My research has focused on the mechanism through which chromatid breaks are formed
from initial DSBs. The lack of a direct association suggested that a signalling process might
be involved, connecting the initial DSB and resulting chromatid break. The signal model,
suggested that the initial DSB is located within a chromatin loop that leads to an intra- or
interchromatid rearrangement resulting in incomplete mis-joining of chromatin ends during the
decatenation of chromatids during G 2 . It was therefore proposed that topoisomerase II alpha
(topo IIα) might be involved, mainly because of its ability to incise DNA and its role in sister
chromatid decatenation.
During my PhD research I have used a strategy of altering topo II activity or expression and
studying whether this alters IR-induced chromatid break frequency. The first approach
involved cell lines that varied in topo IIα expression. The frequency of IR-induced chromatid
breaks was found to correlate positively with topo IIα expression level, as measured in three
different cell lines by immunoblotting, i.e. two cell lines with lower topo IIα expression
exhibited lower chromatid break frequency. Topo II activity in these three cell lines was also
estimated indirectly by the ability of a topo IIα poison to activate the G 2 /M checkpoint, and this
related well with topo IIα expression. A second approach involved ‘knocking down’ topo IIα
protein expression by silencing RNA (siRNA). Lowered topo IIα expression was confirmed by
immunoblotting and polymerase chain reaction. SiRNA-lowered topo IIα expression
correlated with a decreased IR-induced chromatid break frequency. In a third series of experiments cells were treated with ICRF-193, a topo IIα catalytic inhibitor. It was shown that
inhibition of topo IIα also significantly reduced IR-induced chromatid breaks. I also showed
that lowered chromatid break frequency was not due to cells with high chromatid break
frequencies being blocked in G 2 as the mitotic index was not altered significantly in cells with
lowered topo IIα expression or activity. These experiments show that topo IIα is involved in
IR-induced chromatid break formation.
The final experiments reported here attempted to show how topo II might be recruited in the
process of forming IR-induced chromatid breaks. Hydrogen peroxide was used as a source of
reactive oxygen species (reported to poison topo IIα) and it was shown that topo IIα under
these conditions is involved in the entanglement of metaphase chromosomes and formation
of chromatin ‘dots’ as well as chromatid breaks. Experiments using atomic force microscopy
attempted to confirm these dots as excised chromatin loops.
The possible role of topo IIα in both radiation- and hydrogen peroxide-induced primary DNA
damage was also tested. It was shown that topo IIα does not affect radiation-induced DSBs,
even though it does affect chromatid break frequency. Also, topo IIα does not affect hydrogen
peroxide-induced DNA damage at low doses. The results support the idea that topo IIα is
involved in the conversion of DSBs to chromatid breaks after both irradiation and treatment
with hydrogen peroxide at a low concentrations.
I have demonstrated that topo IIα is involved in forming IR-induced chromatid breaks, most
likely by converting the initial DSBs into chromosomal aberrations as suggested by the signal
model.
2010-06-01T00:00:00ZTerry, Samantha Y.A.Human response to ionising radiation (IR) shows a wide variation. This is most clearly seen in
the radiation-response of cells as measured by frequencies of chromosomal aberrations.
Different frequencies of IR-induced aberrations can be conveniently observed in
phytohaemagglutin-stimulated peripheral blood T-lymphocytes from both normal individuals
and sporadic cancer cases, in either metaphase chromosomes or as micronuclei in the
following cell cycle. Metaphase cells show frequent chromatid breaks, defined as chromatid
discontinuities or terminal deletions, if irradiated in the G 2 -phase of the cell cycle. It has been
shown that the frequency of chromatid breaks in cells from approximately 40% of sporadic
breast cancer patients, are significantly higher than in groups of normal individuals. This
suggests that elevated radiation-induced chromatid break frequency may be linked with
susceptibility to breast cancer.
It is known that chromatid breaks are initiated by a double strand break (DSB), but it appears
that the two are linked only indirectly as repair kinetics for DSBs and chromatid breaks do not
match. Therefore, the underlying causes of the wide variation in frequencies of chromatid
breaks in irradiated T-lymphocytes from different normal individuals and from sporadic breast
cancer cases are still unclear but it is unlikely to be linked directly to DSB rejoining.
My research has focused on the mechanism through which chromatid breaks are formed
from initial DSBs. The lack of a direct association suggested that a signalling process might
be involved, connecting the initial DSB and resulting chromatid break. The signal model,
suggested that the initial DSB is located within a chromatin loop that leads to an intra- or
interchromatid rearrangement resulting in incomplete mis-joining of chromatin ends during the
decatenation of chromatids during G 2 . It was therefore proposed that topoisomerase II alpha
(topo IIα) might be involved, mainly because of its ability to incise DNA and its role in sister
chromatid decatenation.
During my PhD research I have used a strategy of altering topo II activity or expression and
studying whether this alters IR-induced chromatid break frequency. The first approach
involved cell lines that varied in topo IIα expression. The frequency of IR-induced chromatid
breaks was found to correlate positively with topo IIα expression level, as measured in three
different cell lines by immunoblotting, i.e. two cell lines with lower topo IIα expression
exhibited lower chromatid break frequency. Topo II activity in these three cell lines was also
estimated indirectly by the ability of a topo IIα poison to activate the G 2 /M checkpoint, and this
related well with topo IIα expression. A second approach involved ‘knocking down’ topo IIα
protein expression by silencing RNA (siRNA). Lowered topo IIα expression was confirmed by
immunoblotting and polymerase chain reaction. SiRNA-lowered topo IIα expression
correlated with a decreased IR-induced chromatid break frequency. In a third series of experiments cells were treated with ICRF-193, a topo IIα catalytic inhibitor. It was shown that
inhibition of topo IIα also significantly reduced IR-induced chromatid breaks. I also showed
that lowered chromatid break frequency was not due to cells with high chromatid break
frequencies being blocked in G 2 as the mitotic index was not altered significantly in cells with
lowered topo IIα expression or activity. These experiments show that topo IIα is involved in
IR-induced chromatid break formation.
The final experiments reported here attempted to show how topo II might be recruited in the
process of forming IR-induced chromatid breaks. Hydrogen peroxide was used as a source of
reactive oxygen species (reported to poison topo IIα) and it was shown that topo IIα under
these conditions is involved in the entanglement of metaphase chromosomes and formation
of chromatin ‘dots’ as well as chromatid breaks. Experiments using atomic force microscopy
attempted to confirm these dots as excised chromatin loops.
The possible role of topo IIα in both radiation- and hydrogen peroxide-induced primary DNA
damage was also tested. It was shown that topo IIα does not affect radiation-induced DSBs,
even though it does affect chromatid break frequency. Also, topo IIα does not affect hydrogen
peroxide-induced DNA damage at low doses. The results support the idea that topo IIα is
involved in the conversion of DSBs to chromatid breaks after both irradiation and treatment
with hydrogen peroxide at a low concentrations.
I have demonstrated that topo IIα is involved in forming IR-induced chromatid breaks, most
likely by converting the initial DSBs into chromosomal aberrations as suggested by the signal
model.Cell cycle control and its modulation in HPV infected cellsLyman, Rachel C.https://hdl.handle.net/10023/8632019-07-01T10:15:27Z2010-07-01T00:00:00ZA key effect of human papillomavirus (HPV) infection is to disrupt the normal cell cycle in order to subvert the cellular DNA replication machinery. Morphologically, condylomata induced by high and low risk HPV types cannot be distinguished and many studies have shown that the pattern of viral gene expression is similar in condylomata caused by both high risk and low risk HPV types. Detailed morphological study of cell cycle protein expression has not previously been performed on condylomata infected with low risk HPV types.
The findings presented suggest that the mechanisms employed by low risk HPV6 or HPV11 to subvert cellular functions in condylomata acuminata are similar to those employed by high risk HPVs, with the exception of cyclin D1 and p53 protein over-expression. The differences in p53 expression and cyclin D1 expression seen between high and low risk HPV infection, reflect the known differences between high and low risk types and are in agreement with the known differences between high risk and low risk E6 and E7 proteins. PHK transduction studies demonstrated HPV E6 and E7 induce changes in cell cycle protein expression and that there are differences in cell cycle abrogation between HPV6 and HPV16.
Disruption of the p53-MDM2 interaction can lead to activation of the p53 pathway. HPV infected lesions almost always contain wild-type p53. The binding of HPV E6 to p53, and its subsequent targeting for degradation, prevents activation of the p53 pathway in HPV infected cells. Cells over expressing HPV genes were treated with Nutlin-3, a MDM2-small molecule antagonist. The findings presented suggest treatment with Nutlin-3 induces cell cycle arrest in cells expressing HPV16 E7 and HPV6 E6 and HPV6 E7. This suggests a potential role for Nutlin-3 in the treatment of HPV infected cells.
2010-07-01T00:00:00ZLyman, Rachel C.A key effect of human papillomavirus (HPV) infection is to disrupt the normal cell cycle in order to subvert the cellular DNA replication machinery. Morphologically, condylomata induced by high and low risk HPV types cannot be distinguished and many studies have shown that the pattern of viral gene expression is similar in condylomata caused by both high risk and low risk HPV types. Detailed morphological study of cell cycle protein expression has not previously been performed on condylomata infected with low risk HPV types.
The findings presented suggest that the mechanisms employed by low risk HPV6 or HPV11 to subvert cellular functions in condylomata acuminata are similar to those employed by high risk HPVs, with the exception of cyclin D1 and p53 protein over-expression. The differences in p53 expression and cyclin D1 expression seen between high and low risk HPV infection, reflect the known differences between high and low risk types and are in agreement with the known differences between high risk and low risk E6 and E7 proteins. PHK transduction studies demonstrated HPV E6 and E7 induce changes in cell cycle protein expression and that there are differences in cell cycle abrogation between HPV6 and HPV16.
Disruption of the p53-MDM2 interaction can lead to activation of the p53 pathway. HPV infected lesions almost always contain wild-type p53. The binding of HPV E6 to p53, and its subsequent targeting for degradation, prevents activation of the p53 pathway in HPV infected cells. Cells over expressing HPV genes were treated with Nutlin-3, a MDM2-small molecule antagonist. The findings presented suggest treatment with Nutlin-3 induces cell cycle arrest in cells expressing HPV16 E7 and HPV6 E6 and HPV6 E7. This suggests a potential role for Nutlin-3 in the treatment of HPV infected cells.Development of a predictive DNA double strand break assay for the identification of individuals with high normal tissue radiosensitivityBrown, Emma Jane Hayhttps://hdl.handle.net/10023/8552019-04-01T08:53:37Z2008-01-01T00:00:00ZA genetically determined high level of intrinsic normal tissue radiosensitivity may account
for the 5% of patients who experience unexpectedly severe normal tissue side effects
following radiotherapy. The pre-treatment identification of these individuals by a
diagnostic test or “predictive assay “ may allow appropriate modification of treatment
plans and improve the therapeutic index of radiotherapy.
Results from studies of cell-based assays measuring the response of a single cell type taken
from patients to in vitro irradiation have been inconsistent, leading to the opinion of many
that they are of no value in the prediction of normal tissue radiosensitivity.
A systematic review of the literature presented here, however, suggests that poor
methodology of study design often with inadequate control for those factors other than
normal tissue radiosensitivity which influence radiotherapy toxicity and lack of reporting
of assay precision means that it is difficult to form any conclusions, positive or negative
about the diagnostic accuracy of the cell-based assays studied so far. Analysis of
individual patient data extracted from these studies suggests that at least some of these
assays may possess some discriminatory value.
This finding justified an attempt to develop a novel cell-based assay based on the kinetics
of radiation-induced .H2AX in peripheral blood lymphocytes. Assay failure rate was high
and intra- and inter-sample assay reproducibility was poor for quantification by
microscopy but were better for flow cytometric analysis. A study of 8 volunteers, however,
demonstrated that intra-individual variation was higher than inter-individual variation in
assay results, strongly suggesting that poor assay reproducibility due to technical or
biological factors may limit the assay’s potential to identify radiosensitive individuals.
This suspicion needs to be confirmed in a clinical study of patients of known
radiosensitivity. As blood sample storage conditions affect assay results these will need to
be standardized to prevent confounding of results.
2008-01-01T00:00:00ZBrown, Emma Jane HayA genetically determined high level of intrinsic normal tissue radiosensitivity may account
for the 5% of patients who experience unexpectedly severe normal tissue side effects
following radiotherapy. The pre-treatment identification of these individuals by a
diagnostic test or “predictive assay “ may allow appropriate modification of treatment
plans and improve the therapeutic index of radiotherapy.
Results from studies of cell-based assays measuring the response of a single cell type taken
from patients to in vitro irradiation have been inconsistent, leading to the opinion of many
that they are of no value in the prediction of normal tissue radiosensitivity.
A systematic review of the literature presented here, however, suggests that poor
methodology of study design often with inadequate control for those factors other than
normal tissue radiosensitivity which influence radiotherapy toxicity and lack of reporting
of assay precision means that it is difficult to form any conclusions, positive or negative
about the diagnostic accuracy of the cell-based assays studied so far. Analysis of
individual patient data extracted from these studies suggests that at least some of these
assays may possess some discriminatory value.
This finding justified an attempt to develop a novel cell-based assay based on the kinetics
of radiation-induced .H2AX in peripheral blood lymphocytes. Assay failure rate was high
and intra- and inter-sample assay reproducibility was poor for quantification by
microscopy but were better for flow cytometric analysis. A study of 8 volunteers, however,
demonstrated that intra-individual variation was higher than inter-individual variation in
assay results, strongly suggesting that poor assay reproducibility due to technical or
biological factors may limit the assay’s potential to identify radiosensitive individuals.
This suspicion needs to be confirmed in a clinical study of patients of known
radiosensitivity. As blood sample storage conditions affect assay results these will need to
be standardized to prevent confounding of results.The role of HLA-B27 in inflammatory arthritisLynch, Sarah Janicehttps://hdl.handle.net/10023/8342019-07-01T10:17:42Z2009-11-01T00:00:00ZThe MHC class I allele, HLA-B27, is strongly associated with a group of inflammatory arthritic conditions collectively known as spondyloarthropathies (SpA). Ankylosing spondylitis (AS) shows the strongest association with 90-95 % of patients being HLA-B27 positive. The relationship between HLA-B27 and SpA has been known for over 30 years, however despite ongoing research, the reason for this association has not yet been elucidated. In more recent years, research has focused on intrinsic properties of the HLA-B27 allele, in particular its propensity to misfold, forming homodimers. It has been proposed that these homodimers could be associated with the disease process through the activation of an ER stress response known as the unfolded protein response (UPR), or through aberrant recognition at the cell surface.
We have investigated whether the expression of HLA-B27 is associated with the activation of the UPR. We have studied the expression of BiP, and the cleavage of XBP1 and ATF6 using stable and transiently expressing cell lines. We have also investigated the formation of non-B27 homodimers using a human cell line stably expressing HLA-B8, and finally we have studied the expression of homodimers in exosomes, small immunomodulatory vesicles released from numerous cell types. The results presented here lead us to conclude that in vitro studies of the UPR are complicated, prone to a number of technical issues, and may therefore not be appropriate for gaining information that would be of significant use when comparing to the real disease scenario. Our data suggest that non-B27 dimers may be strongly influenced by both the overexpression of MHC class I heavy chains and also the redox environment within the cell.
We have isolated a novel fully folded, beta-2m-associated, MHC class I homodimer in exosomes and have detected a novel HLA-A and HLA-B mixed heavy chain dimer. Our results suggest that these dimers form through interactions between the cysteine residues in the cytoplasmic tail and that these dimers form in exosomes because they contain lower levels of the important antioxidant glutathione when compared to whole cells. Together, these results define a new MHC class I structure present on exosomes at significant levels, which could potentially influence immune recognition by both antigen-specific T cell receptors and NK family receptors. The data also poses questions about whether these novel structures, when they involve HLA-B27, could influence the pathogenesis of spondyloarthropathies.
Electronic version excludes material for which permission has not been granted by the rights holder
2009-11-01T00:00:00ZLynch, Sarah JaniceThe MHC class I allele, HLA-B27, is strongly associated with a group of inflammatory arthritic conditions collectively known as spondyloarthropathies (SpA). Ankylosing spondylitis (AS) shows the strongest association with 90-95 % of patients being HLA-B27 positive. The relationship between HLA-B27 and SpA has been known for over 30 years, however despite ongoing research, the reason for this association has not yet been elucidated. In more recent years, research has focused on intrinsic properties of the HLA-B27 allele, in particular its propensity to misfold, forming homodimers. It has been proposed that these homodimers could be associated with the disease process through the activation of an ER stress response known as the unfolded protein response (UPR), or through aberrant recognition at the cell surface.
We have investigated whether the expression of HLA-B27 is associated with the activation of the UPR. We have studied the expression of BiP, and the cleavage of XBP1 and ATF6 using stable and transiently expressing cell lines. We have also investigated the formation of non-B27 homodimers using a human cell line stably expressing HLA-B8, and finally we have studied the expression of homodimers in exosomes, small immunomodulatory vesicles released from numerous cell types. The results presented here lead us to conclude that in vitro studies of the UPR are complicated, prone to a number of technical issues, and may therefore not be appropriate for gaining information that would be of significant use when comparing to the real disease scenario. Our data suggest that non-B27 dimers may be strongly influenced by both the overexpression of MHC class I heavy chains and also the redox environment within the cell.
We have isolated a novel fully folded, beta-2m-associated, MHC class I homodimer in exosomes and have detected a novel HLA-A and HLA-B mixed heavy chain dimer. Our results suggest that these dimers form through interactions between the cysteine residues in the cytoplasmic tail and that these dimers form in exosomes because they contain lower levels of the important antioxidant glutathione when compared to whole cells. Together, these results define a new MHC class I structure present on exosomes at significant levels, which could potentially influence immune recognition by both antigen-specific T cell receptors and NK family receptors. The data also poses questions about whether these novel structures, when they involve HLA-B27, could influence the pathogenesis of spondyloarthropathies.Development of an in vitro model for investigating the properties of human prostate epithelial cells and prostatic carcinoma cellsWeaver, Jenniferhttps://hdl.handle.net/10023/7552019-07-01T10:06:42Z2009-06-26T00:00:00ZProstate cell lines were derived from two regions of prostate tissue from the same patient. The objective was to produce cell lines (as a useful in vitro model) from these two different regions which exhibit different properties for carcinoma development. The tissue was obtained from patients suffering from benign prostate hyperplasia undergoing trans-urethral resection. Tissue was taken from the deep (peripheral) and superficial (peri-urethral) areas. The cells were immortalised by transduction with constructs over expressing the cdk4 and hTERT genes. These cell lines were then characterised for their cellular phenotypes utilized for radiation transformation studies and utilized to investigate the role of plant derived polyphenols on normal and tumour cells.
The cell line from the superficial region (P21s) was treated to fractionated doses of gamma radiation and a transformed cloned cell line was derived (P21s 40Gy (clone-a)). The cell line from the deep region (P21d) was found to consist of a mixed population of abnormal cells and a transformed cloned cell line was derived from it (P21d 0Gy (clone-a). In an attempt to obtain a normal P21d cell line cloned cell lines from early passage P21d cells were established. All seven cloned lines were abnormal with an average of 80 chromosomes per cell, invasive using a Matrigel assay and produced anchorage independent colonies. All cell lines were fully characterised with immunocytochemistry, chromosome analysis, invasion assays, and anchorage independent colony formation. P21s expressed basal cell markers (cytokeratin 5 (CK5) and 14), were positive for stem cell markers (prostate specific stem cell antigen PSCA, CK6), positive for p16, p63 and telomerase expression and negative for c-Myc expression. P21s was not invasive in a Matrigel assay and did not produce anchorage independent colony formation. P21d and P21d 0Gy (clone-a) also expressed CK5, CK14, PSCA, CK6, and telomerase but not p16 or p63 and showed an increase in expression of nuclear c-Myc, highly invasive and produced anchorage independent colonies. P21s 40Gy (clone-a) expressed CK5, CK14, PSCA, CK6, telomerase and p63, produced anchorage independent colonies, and was weakly positive for c-Myc expression.
Spectral karyotyping analysis (SKY) showed P21s had a normal chromosome complement except an additional chromosome 20 whereas the P21s 40Gy (clone-a), P21d and P21d 0Gy (clone-a) cell lines had an abnormal chromosome complement with P21d and P21d 0Gy (clone-a) cell lines expressing multiple copies of every chromosome including loss of the Y chromosome. These results were echoed in the single nucleotide polymorphism chip (SNP) results which showed P21s as normal but P21d and P21d 0Gy (clone-a) to have large deletion and amplification regions that correlated with the SKY analysis.
No differential cytotoxic response was noted between normal and abnormal cell lines including prostatic carcinoma cell lines LNCaP and PC-3 following treatment with strawberry polyphenol compounds. Most reports of a cytotoxic response to tumour cells in the literature did not compare the response to normal cells and used established cell lines. Human lymphocytes were also tested and all compounds were toxic in high doses. Polyphenol and ellagitannin rich polyphenol fractions were very cytotoxic and the anthocyanin rich fraction less toxic. In contrast to the lack of a direct differential cytotoxic effect, plant polyphenols did produce a protective effect to a carcinogenic insult. However a protective effect was noted via micronucleus assay with 3 hour incubation with the polyphenol rich fraction prior to radiation treatment.
Finally, the expression and association of metabolic enzymes within the cells cytosol were investigated. The P21s cells were found to express both isoforms of LDH and so thought to be able to metabolise anaerobically and aerobically. P21d and P21d 0Gy (clone-a) cells were found to only express one isoform in the complex and so it was assumed that these cells favoured anaerobic metabolism of ATP in correlation to the Warburg effect. c-Myc association with compounds in the cell cytosol of P21s cells existed whereas, abnormal cells lost this association along with up-regulation of c-Myc expression and down stream targets of c-Myc in the nuclei.
Thus these newly established human prostate cell lines provide a useful model system for investigating the biology of the prostate and prostate cancer.
2009-06-26T00:00:00ZWeaver, JenniferProstate cell lines were derived from two regions of prostate tissue from the same patient. The objective was to produce cell lines (as a useful in vitro model) from these two different regions which exhibit different properties for carcinoma development. The tissue was obtained from patients suffering from benign prostate hyperplasia undergoing trans-urethral resection. Tissue was taken from the deep (peripheral) and superficial (peri-urethral) areas. The cells were immortalised by transduction with constructs over expressing the cdk4 and hTERT genes. These cell lines were then characterised for their cellular phenotypes utilized for radiation transformation studies and utilized to investigate the role of plant derived polyphenols on normal and tumour cells.
The cell line from the superficial region (P21s) was treated to fractionated doses of gamma radiation and a transformed cloned cell line was derived (P21s 40Gy (clone-a)). The cell line from the deep region (P21d) was found to consist of a mixed population of abnormal cells and a transformed cloned cell line was derived from it (P21d 0Gy (clone-a). In an attempt to obtain a normal P21d cell line cloned cell lines from early passage P21d cells were established. All seven cloned lines were abnormal with an average of 80 chromosomes per cell, invasive using a Matrigel assay and produced anchorage independent colonies. All cell lines were fully characterised with immunocytochemistry, chromosome analysis, invasion assays, and anchorage independent colony formation. P21s expressed basal cell markers (cytokeratin 5 (CK5) and 14), were positive for stem cell markers (prostate specific stem cell antigen PSCA, CK6), positive for p16, p63 and telomerase expression and negative for c-Myc expression. P21s was not invasive in a Matrigel assay and did not produce anchorage independent colony formation. P21d and P21d 0Gy (clone-a) also expressed CK5, CK14, PSCA, CK6, and telomerase but not p16 or p63 and showed an increase in expression of nuclear c-Myc, highly invasive and produced anchorage independent colonies. P21s 40Gy (clone-a) expressed CK5, CK14, PSCA, CK6, telomerase and p63, produced anchorage independent colonies, and was weakly positive for c-Myc expression.
Spectral karyotyping analysis (SKY) showed P21s had a normal chromosome complement except an additional chromosome 20 whereas the P21s 40Gy (clone-a), P21d and P21d 0Gy (clone-a) cell lines had an abnormal chromosome complement with P21d and P21d 0Gy (clone-a) cell lines expressing multiple copies of every chromosome including loss of the Y chromosome. These results were echoed in the single nucleotide polymorphism chip (SNP) results which showed P21s as normal but P21d and P21d 0Gy (clone-a) to have large deletion and amplification regions that correlated with the SKY analysis.
No differential cytotoxic response was noted between normal and abnormal cell lines including prostatic carcinoma cell lines LNCaP and PC-3 following treatment with strawberry polyphenol compounds. Most reports of a cytotoxic response to tumour cells in the literature did not compare the response to normal cells and used established cell lines. Human lymphocytes were also tested and all compounds were toxic in high doses. Polyphenol and ellagitannin rich polyphenol fractions were very cytotoxic and the anthocyanin rich fraction less toxic. In contrast to the lack of a direct differential cytotoxic effect, plant polyphenols did produce a protective effect to a carcinogenic insult. However a protective effect was noted via micronucleus assay with 3 hour incubation with the polyphenol rich fraction prior to radiation treatment.
Finally, the expression and association of metabolic enzymes within the cells cytosol were investigated. The P21s cells were found to express both isoforms of LDH and so thought to be able to metabolise anaerobically and aerobically. P21d and P21d 0Gy (clone-a) cells were found to only express one isoform in the complex and so it was assumed that these cells favoured anaerobic metabolism of ATP in correlation to the Warburg effect. c-Myc association with compounds in the cell cytosol of P21s cells existed whereas, abnormal cells lost this association along with up-regulation of c-Myc expression and down stream targets of c-Myc in the nuclei.
Thus these newly established human prostate cell lines provide a useful model system for investigating the biology of the prostate and prostate cancer.Modification of the E1-pIX region of the adenovirus 5 genome for use in cancer gene therapyKallioinen, Susanna E.https://hdl.handle.net/10023/4422019-04-01T08:52:38Z2008-01-01T00:00:00ZCurrently the use of adenoviruses in cancer gene therapy is limited by efficient
delivery of the virus into the tumour cells, detargeting of the virus from the liver, and
the efficient spread of the virus within the tumour. Rapid and easy modification of
adenoviruses enables expression of different genes from the genome of an oncolytic
virus. I developed a system where the E1-pIX region of the adenovirus 5 genome
could be mutated via recombination of a recipient virus with the deleted E1-pIX
region flanked by a loxP and an attB-site and an “addback” plasmid with the mutated
E1-pIX region flanked by a loxP and an attP-site. The recipient virus was found not to
be producible even on a pIX-complementing cell line. The pIX was further modified
by fusing GFP, FCU1 and MMP7 to the C-terminus with a 2A sequence that enables
the ribosome to skip one specific peptide bond enabling the expression of genes
flanking this sequence. Two different 2A sequences were used: FMDV 2A (F2A) and
PTV-1 2A (P2A). The pIX-P2A-GFP expressing virus was found to have similar heat
stability, CPE, burst size and plaque size characteristics as the parental virus, whereas
the pIX-F2A-GFP expressing virus was found to have reduced heat stability, CPE,
burst size and smaller plaque size. The viruses expressing FCU1 and MMP7 were
found only to be producible on a pIX-complementing cell line due to the low
expression of pIX from these constructs. I concluded that 2A sequences can be used
in the context of adenoviruses but optimisation of the sequence may be needed
depending on the fusion partners.
2008-01-01T00:00:00ZKallioinen, Susanna E.Currently the use of adenoviruses in cancer gene therapy is limited by efficient
delivery of the virus into the tumour cells, detargeting of the virus from the liver, and
the efficient spread of the virus within the tumour. Rapid and easy modification of
adenoviruses enables expression of different genes from the genome of an oncolytic
virus. I developed a system where the E1-pIX region of the adenovirus 5 genome
could be mutated via recombination of a recipient virus with the deleted E1-pIX
region flanked by a loxP and an attB-site and an “addback” plasmid with the mutated
E1-pIX region flanked by a loxP and an attP-site. The recipient virus was found not to
be producible even on a pIX-complementing cell line. The pIX was further modified
by fusing GFP, FCU1 and MMP7 to the C-terminus with a 2A sequence that enables
the ribosome to skip one specific peptide bond enabling the expression of genes
flanking this sequence. Two different 2A sequences were used: FMDV 2A (F2A) and
PTV-1 2A (P2A). The pIX-P2A-GFP expressing virus was found to have similar heat
stability, CPE, burst size and plaque size characteristics as the parental virus, whereas
the pIX-F2A-GFP expressing virus was found to have reduced heat stability, CPE,
burst size and smaller plaque size. The viruses expressing FCU1 and MMP7 were
found only to be producible on a pIX-complementing cell line due to the low
expression of pIX from these constructs. I concluded that 2A sequences can be used
in the context of adenoviruses but optimisation of the sequence may be needed
depending on the fusion partners.Biomarkers of isoflavone intake : validity at high intakesMackinnon, L. Jayhttps://hdl.handle.net/10023/2222019-07-01T10:04:42Z2007-06-01T00:00:00ZIsoflavones are biologically active plant chemicals (phytoestrogens) which are ordinarily
present in human diets. There is considerable research interest in their potential to
prevent or treat several chronic diseases. Biomarkers can demonstrate compliance during
dietary interventions and validate associations between intake of isoflavones and health
outcomes.
The objectives of this study were to validate 24-hour urine collections, timed spot urine
samples and timed plasma samples as biomarkers of isoflavone intake up to 165mg/day.
Healthy volunteers (20 women and 11 men) consumed 55mg/d, 110mg/d or 165mg/d soy isoflavones or placebo for seven consecutive days in a randomised, double-blind, crossover study. Timed blood samples, timed spot urine samples (taken in the afternoon, 5-7 hours after consuming the isoflavone supplement) and 24-hour urines were obtained at baseline and during each intervention. Isoflavone content of the samples was assayed by
liquid chromatography and mass spectrometry. 24-hour urines were validated by percentage PABA recovery.
The relationship between daily isoflavone intake and 24-hour urinary isoflavone excretion was:
y = 6.63132xº•⁷⁴²¹
≡ x = (y ÷ 6.63132)¹•³⁴⁷⁵
where y = isoflavone excretion in μg/24h and x = isoflavone intake in μg/24h
r² = 0.86; p < 0.001; n = 109 samples from 31 volunteers.
The relationship between daily isoflavone intake and plasma isoflavone concentration was:
y = (3.3543x10⁻³)xº•⁴⁸⁸⁹
≡ x = (y ÷ 3.3543x10⁻³)²•º⁴⁵⁴
where y = plasma isoflavone in μg/ml and x = isoflavone intake in μg/24h
r² = 0.61; p < 0.001; n = 100 samples from 30 volunteers.
The relationship between daily isoflavone intake and spot urine isoflavone concentration was:
y = (2.0324x10⁻³)xº•⁸ºº⁹
≡ x = (y ÷ 2.0324x10⁻³)¹•²⁴⁸⁶
where y = isoflavone excretion in μg/ml and x = isoflavone intake in μg/24h
r² = 0.69; p < 0.001; n = 143 samples from 31 volunteers.
It was concluded that 24-hour urine collections, timed plasma samples and timed spot urine samples are valid biomarkers of isoflavone intakes up to 165mg/day. A curvilinear relationship was defined between a) isoflavone dose and bioavailability in plasma and b) isoflavone dose and 24-hour urinary excretion.
2007-06-01T00:00:00ZMackinnon, L. JayIsoflavones are biologically active plant chemicals (phytoestrogens) which are ordinarily
present in human diets. There is considerable research interest in their potential to
prevent or treat several chronic diseases. Biomarkers can demonstrate compliance during
dietary interventions and validate associations between intake of isoflavones and health
outcomes.
The objectives of this study were to validate 24-hour urine collections, timed spot urine
samples and timed plasma samples as biomarkers of isoflavone intake up to 165mg/day.
Healthy volunteers (20 women and 11 men) consumed 55mg/d, 110mg/d or 165mg/d soy isoflavones or placebo for seven consecutive days in a randomised, double-blind, crossover study. Timed blood samples, timed spot urine samples (taken in the afternoon, 5-7 hours after consuming the isoflavone supplement) and 24-hour urines were obtained at baseline and during each intervention. Isoflavone content of the samples was assayed by
liquid chromatography and mass spectrometry. 24-hour urines were validated by percentage PABA recovery.
The relationship between daily isoflavone intake and 24-hour urinary isoflavone excretion was:
y = 6.63132xº•⁷⁴²¹
≡ x = (y ÷ 6.63132)¹•³⁴⁷⁵
where y = isoflavone excretion in μg/24h and x = isoflavone intake in μg/24h
r² = 0.86; p < 0.001; n = 109 samples from 31 volunteers.
The relationship between daily isoflavone intake and plasma isoflavone concentration was:
y = (3.3543x10⁻³)xº•⁴⁸⁸⁹
≡ x = (y ÷ 3.3543x10⁻³)²•º⁴⁵⁴
where y = plasma isoflavone in μg/ml and x = isoflavone intake in μg/24h
r² = 0.61; p < 0.001; n = 100 samples from 30 volunteers.
The relationship between daily isoflavone intake and spot urine isoflavone concentration was:
y = (2.0324x10⁻³)xº•⁸ºº⁹
≡ x = (y ÷ 2.0324x10⁻³)¹•²⁴⁸⁶
where y = isoflavone excretion in μg/ml and x = isoflavone intake in μg/24h
r² = 0.69; p < 0.001; n = 143 samples from 31 volunteers.
It was concluded that 24-hour urine collections, timed plasma samples and timed spot urine samples are valid biomarkers of isoflavone intakes up to 165mg/day. A curvilinear relationship was defined between a) isoflavone dose and bioavailability in plasma and b) isoflavone dose and 24-hour urinary excretion.