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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Characteristics and consequences of antenatal exposure to selective serotonin reuptake inhibitors

Julyan, Tom Everett January 2018 (has links)
Depression is a common condition, affecting around one in 20 people worldwide. It is challenging conceptually and clinically, with treatment being ineffective for many, and significant consequences for individuals and societies alike. Depression is particularly problematic during pregnancy, where it is no less common, but poses additional difficulties. Both depression and its pharmacological treatments are associated with a range of short- and longer- term sequelae for offspring, and current data is insufficient to allow fully informed decisions to be made by mothers, midwives, or doctors. Research is affected by practical, ethical, and methodological issues, and a myriad of confounding factors, which combine to increase uncertainties over the risks and benefits of prescribing (or not). Retrospective and prospective observational studies accompany epidemiological data linkage and meta- analyses involving millions of subjects, in contributing to both current knowledge and testable hypotheses to inform future directions for research, while clinical and preclinical studies with smaller sample sizes provide invaluable and complementary details. However, significant gaps remain, not least in delivering optimal care to each individual mother and baby. While the overall emerging picture appears reassuring to some, others acknowledge that we do not even possess all the pieces of the puzzle yet. There remains an urgent need for more comprehensive and relevant data. This thesis presents the findings from a series of pilot studies on evaluating the characteristics and consequences of antenatal exposure to selective serotonin reuptake inhibitors. Up to one in 10 women in the general Scottish population may be exposed to an antidepressant at some point during pregnancy, but adverse outcomes may be related more to underlying maternal depression, rather than its pharmacological treatment. We highlight areas of both intelligence and ignorance, and make proposals for future research.
242

Risk factors for the onset of musculoskeletal pain in children and adolescents

Andreucci, Alessandro January 2018 (has links)
Background: Musculoskeletal pain is a major burden on society. Research in adults has identified risk factors associated with musculoskeletal pain onset, however at present evidence for risk factors in children and adolescents is limited. Aims: Identify potential risk factors for musculoskeletal pain onset in children and adolescents from current literature, and generate specific hypotheses to be tested using existing cohort data. Methods: A systematic review was conducted to summarize existing evidence of risk factors for musculoskeletal pain onset in children and adolescents. Two child and adolescent prospective cohort datasets and a local primary care consultation database were used to test hypotheses using logistic and survival regression analysis. Results: The systematic review found evidence that sleep problems and psychological symptoms (internalizing and externalizing) were associated with musculoskeletal pain onset with added evidence of potential effect modifiers. For sleep problems, analysis within a prospective cohort showed higher odds (OR 1.35, 95%CI 0.84, 2.16) for musculoskeletal pain onset, but this association was significant only for chronic pain onset (OR 2.22, 95%CI 1.43, 3.44), with evidence of effect modification by gender (association was stronger in boys). Testing within a primary care cohort showed a 49% increased hazard of sleep consultations with musculoskeletal consultations. In a cohort of adolescents musculoskeletal pain was not significantly associated with internalizing symptoms (OR 1.43, 95%CI 0.96, 2.12), however a significant association was found for externalizing symptoms (adjusted OR 1.99, 95% CI 1.28, 3.10), with evidence of effect modification by pubertal status and screen time use. Testing in a primary care cohort revealed a 39% increased hazard for musculoskeletal consultations. Conclusions: Potential risk factors (sleep and psychological symptoms) and effect modifiers were identified for (chronic) musculoskeletal pain onset within child and adolescent population and primary care samples. Future work is required to explore mechanisms explaining these associations, and develop appropriate interventions.
243

The early use of botulinum toxin in post stroke spasticity : developing a new approach to contracture management

Lindsay, Cameron January 2018 (has links)
Introduction: Patients surviving a severe stroke are at risk of developing contractures. Evidence suggests that spasticity may be a cause of contractures, particularly in patients who have not recovered functional movement. The relationship and the time course of spasticity and contractures remain unclear. This thesis aims to identify when spasticity can be identified and investigate whether treating spasticity at onset using botulinum-toxin, might slow contracture development. Methods: A double blind randomised placebo-controlled trial with an initial six-week screening phase was conducted in an acute NHS hospital. Patients with no arm function (Action Research Arm Test grasp-score < 2) within six-weeks of stroke were eligible for screening. Screening for spasticity was carried out using a neurophysiological method. Patients who developed spasticity were randomly assigned to receive intra-muscular injections of 0.9%sodium chloride solution or onabotulinumtoxinA. Measures of spasticity and contracture development (reduced passive range of motion (PROM) and increased stiffness) were taken at the wrist and elbow at baseline, weeks-two, four, six and twelve post injection and six-months post stroke. Results: Over a 23-month period, 1143 patients were admitted with stroke and 120 consented to study participation. Of these, 100 developed spasticity without functional recovery 84%(95% confidence interval(95%CI):76%-89%). Mean time of spasticity onset was 13.5-days(SD:8.5). Of the 100 eligible for randomisation 93 were included in intention to treat analysis. At six-weeks, treatment results in a reduction in wrist spasticity (mean difference(MD):4.8μV;95%CI:1.2to8.4;p=0.009), stiffness (MD=4.2mN/deg;95%CI:0.7to7.7;p=0.02) and PROM (MD=13.8o;95%CI:6.1to21.6;p=0.01). At the elbow; four-weeks spasticity (MD=9.8μV;95%CI:4.3to15.4;p=0.001), four-week stiffness (MD=4.8mN/deg;95%CI:-0.1to9.6;p=0.056) and twelve-weeks PROM–(MD=6.5o;95%CI:0.6to12.3;p=0.03). These changes were not maintained at the six-month follow-up assessment. Conclusion: Spasticity occurs earlier and is more common than previously reported. Treating spasticity early with onabotulinumtoxinA can reduce the rate of contracture formation. Further work is required to elucidate who is at greatest risk of contractures and to explore if these treatment effects can be sustained with adjunct therapies.
244

Master John Hall's little book of cures : a critical edition

Wells, Laurence Gregory January 2016 (has links)
This thesis presents a critical edition of John Hall’s casebook (composed around 1634-1635) and commentaries on aspects of it. My research involved close reading of Hall’s Latin, and its translation into English. In the process it became apparent that Hall had made considerable use of unattributed borrowings from Latin medical books, making up between thirty and forty per cent of his text. These were mostly identified by detailed word searches of on-line databases. This is a use of medical texts not previously noted, and makes a clear connexion between Latin medical texts and routine medical practice. The thesis is presented in four sections, plus introduction and conclusion. The first section, the Background, gives the history of Hall’s manuscript from its composition in 1634-35 to its acquisition by the British Library. It sets out the reasons for producing a new translation, the editorial principles and practice followed, and some medical themes running through Hall’s case reports. Section two contains the critical edition itself, with parallel Latin and English texts. Footnotes to the Latin text give the sources of all of Hall’s borrowings from and references to medical and other texts. The third section (Chapter 1) analyses the process and results of identifying Hall’s working library, of forty-three authors and sixty titles, from his borrowings. It puts his library in the early modern medical context in terms of its contents and categories of composition. I show that there were changes in the books Hall acquired over time, from those suitable for a student through to his later interests in chymical practice and the diagnosis of scurvy. Despite these changes, he continued to rely on old familiar texts for most of his remedies throughout his life. The fourth section (Chapter 2) examines Hall’s manuscript in the context of casebooks generally. It differs from the majority of casebooks, the differences being explained by its composition as the draft for a book to be published. It shows that a casebook can have an internal structure related to the chronologies of its composition and the cases it draws on. This thesis demonstrates the importance of Latin sources in at least one medical casebook of the early seventeenth century. I show that borrowings such as Hall’s were not unique even if rarer in other texts. The possibility of a Latin textual source should be considered for any Latin text in a casebook of that period.
245

Outcomes from ultrasound-guided foam sclerotherapy for chronic venous disease

Darvall, Katy Abigail Leigh January 2012 (has links)
The objective of this research is to investigate the role of ultrasound-guided foam sclerotherapy (UGFS) in the treatment of chronic venous disease (CVD). UGFS was found to be a safe and effective treatment for both primary and recurrent great saphenous vein (GSV) and small saphenous vein (SSV) incompetence, assessed by occlusion of treated veins on duplex ultrasound (DUS), and by disappearance of visible varicose veins (VV) on clinical examination. There was some evidence that healing of chronic venous ulcers (CVU) may be improved by UGFS when combined with compression bandaging. When compared with patients undergoing superficial venous surgery (SVS), UGFS was associated with significantly less pain, bruising and analgesia requirement, and a quicker return to work and driving. Significant improvements in both generic physical and disease-specific health-related quality of life (HRQL)were observed following UGFS, and were sustained for 12 months after treatment. UGFS significantly improved lower limb physical symptoms (pain, itching, restlessness, swelling, heaviness, cramp and tingling), cosmetic appearance, and provided life-style benefits in the majority of patients. Furthermore, the great majority of patients who expected such benefits had their expectations met or exceeded.
246

An empirically informed ethical analysis of conditional and directed deceased organ donation

Moorlock, Gregory January 2013 (has links)
This thesis explores the ethics of conditional and directed deceased organ donation. It uses an empirical bioethics approach that uses empirical data to inform and enhance philosophical analysis. An initial philosophical analysis of the key ethical considerations was undertaken, and it is argued that the policy prohibiting most conditional and directed donations is wrong. The concept of altruism, in particular, is poorly conceived and applied in transplantation policy. Qualitative data obtained by interviewing relevant stakeholders are presented. The data suggest that although there are concerns about the consequences of accepting conditional and directed donations, many participants thought these donations should be accepted in some circumstances. The data also provide lines of argument against conditional and directed donations, and these are considered. Using this data, and making some reasonable assumptions, it is argued that it is better to accept conditional and directed donations than it is to reject them. The thesis culminates with 8 recommendations for policy regarding conditional and directed donations, and argues that a trial period of accepting these donations should be implemented so that the effects can be accurately observed.
247

CD28 costimulation in T cells : requirements, outcomes and regulation

Briggs, Zoe Louise January 2014 (has links)
The costimulatory receptor CD28 and its inhibitory counterpart CTLA-4 share the same ligands and comprise a crucial checkpoint in T cell activation. CTLA-4 removes its ligands from antigen presenting cells by trans-endocytosis, which reduces the availability of costimulatory ligands for CD28 engagement to regulate T cell activation. This project examined the functional implications of reducing the availability of costimulatory molecules for CD4 T cell responses, and investigated the use of trans-endocytosis by other T cell receptors. Surprisingly, it was revealed that PD-1 and OX40 can also internalise their ligands, although perhaps not via the same mechanism as CTLA-4 trans-endocytosis. It was also shown that altering the availability of CD28 ligands affects the extent of T cell proliferation, suggesting that CTLA-4 trans-endocytosis can finely tune the T cell response. Furthermore, it was observed that CD28 costimulation is not always required for T cell activation and proliferation, but CD28 engagement is required for the optimal upregulation of a number of effector proteins and for TH2 cytokine production. Interestingly, T cells activated in the absence of CD28 signalling were not classically anergic. Strikingly, it was also found that memory T cells are dependent on CD28 costimulation.
248

Pathophysiology of a mouse model of X-linked mental retardation

Gill, Kalbinder Kaur January 2013 (has links)
Mental retardation (MR) affects 23% of the population; those due to X linked mutations commonly result in moderate to severe MR. The OPHN1 gene (Ophn1 in mice) has been implicated in X linked mental retardation (XLMR) and encodes the RhoGAP protein, oligophrenin 1. Loss of function mutations alter Rho GTPase dependent signalling pathways and result in altered actin cytoskeleton dynamics which are important in dendritic spine structure, the site of neurotransmission. Here, using electrophysiological recordings combined with intracellular staining techniques and dendritic morphological analysis, I characterise synaptic (dys)function in neocortical and hippocampal neurons from the Ophn1 mouse model of MR. This study demonstrates an excitatory synaptic deficit in neocortical neurons combined with region specific changes in dendritic spine morphology. Inhibitory transmission was normal in both neocortical and hippocampal neurons. Kainate induced gamma oscillations were unaltered whereas spontaneous oscillations were reduced which lead to changes in synaptic function in CA3. Morphometric analysis showed ventriculomegaly in Ophn1 deficient mice that was associated with reduced cortical thickness. This study shows the loss of several previously reported phenotypes, including, altered inhibitory transmission, gamma oscillations and vesicle dynamics. Their loss, but preservation of morphological deficits, suggests that the model may be susceptible to genetic drift.
249

Study of Wolfram Syndrome in neuronal cell models

Gharanei, Seley January 2013 (has links)
Wolfram Syndrome (WS) is a rare autosomal recessive disease characterised by insulin-dependent diabetes mellitus, optic nerve atrophy. The current study demonstrated that neuronal cells depleted of WFS1 protein, showed significantly elevated expression of the ER stress markers indicating an enhanced ER stress response. This was accompanied by increased apoptosis and impaired cell cycle progression. WFS1 depletion also resulted in decreased expression of Na+/K+ ATPase beta1 subunit and Vacuolar ATPase (V-ATPase) V1A subunit. The elevated expressions of ER stress markers, but not the decreased expression of pump subunits, were reversed by adenoviral over-expression of BiP/GRP78. Protein degradation assays showed more rapid degradation of both pump subunits in WFS1 depleted cells compared with controls. A novel interaction between WFS1 and the V1A subunit of the vacuolar-type H+-ATPase (proton pump) was demonstrated by co-immunoprecipitation in overexpression system and with endogenous proteins. The interaction was mapped to the WFS1-N terminal, but not the C-terminal domain. In conclusion, this study shows that WFS1 has a specific interaction with the V1A subunit of H+ V-ATPase. Chemical and molecular chaperones TUDCA, GRP78 and the histone deacetylase inhibitor VPA showed promising results in providing protection against ER stress induced apoptosis in WFS1 depleted neuronal cells.
250

Histone modifications across the cell cycle in undifferentiated and differentiating mouse embryonic stem cells

Goss, Hannah Myren January 2014 (has links)
The role of post translational histone modifications in stem cells has been of increasing interest in recent years, however, the heritability of histone modifications has not yet been determined, and as such their status as epigenetic remains in question. Here we have taken the novel approach of comparing the enrichment of histone modifications, across specific genes and how they are modulated through various phases of the cell cycle: in doing so we address this question of heritability from a new perspective. Highly dynamic fluctuations in the enrichment of histone modifications were observed across the cell cycle in embryonic stem cells. In cell cycle regulated genes the patterns of modification enrichment revealed an increase in active marks either pre-emptive or at the point of expression, indicative of highly dynamic regulation, not a stable heritable transmission, perhaps reflective of the plasticity of these cells. Following on from this embryonic stem cells were differentiated for seven days, allowing the enforcement of canonical cell cycle regulation and a more lineage specific transcription profile. At this point histone modifications displayed a variety of patterns including what appeared to be the stable and presumably heritable transmission of H3K4me3 and H3K27me3 across the cell cycle.

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