Anaphylaxis can be triggered by a number of allergens the most common being food, medications, insect venom and latex. Due to the sudden onset and potentially fatal nature of anaphylaxis, successful management requires prompt and appropriate use of emergency medication. A failure to follow recommended medical advice remains a barrier to the control of many medical conditions, and food allergy and anaphylaxis are no exception. Studies have shown that use of emergency medication for anaphylaxis, by both health professionals and patients, is suboptimal. Identification of the nature and extent of health professionals' and patients' poor management of anaphylaxis enabled better understanding of the factors influential in the successful management of anaphylaxis, and guided the application of two Social Cognition Models in this area. This thesis explores the Health Belief Model (HBM) and the Common Sense Model (CSM) to determine if either can explain adherence to self-care behaviours (SCBs) amongst adolescents and young adults with food allergy. A systematic review was conducted of peer reviewed articles to identify health professionals' and patients' poor management of anaphylaxis. Based on these findings, two further systematic reviews were undertaken investigating the effectiveness of HBM and CS M-interventions in improving adherence. Original data was collected in a cross-sectional study of food allergic participants aged 13- 19 years with a prescription of auto-injectable epinephrine recruited from hospital allergy clinics. A postal self-completion questionnaire explored their health beliefs and illness perceptions derived from the models. Clinical and demographic information was collected based on findings from the first systematic review. The systematic review of anaphylaxis management found that poor management was frequently attributed to lack of knowledge and practical ability. However, adherence to preventive SCBs such as allergen avoidance and carrying emergency medication were rarely measured. The HBM and the CSM were found to have been successfully applied to eight and two adherence-related interventions respectively. In the population of 188 allergic adolescents investigated in this study, the HBM, specifically the constructs perceived severity, benefits and barriers, explained the greatest proportion of variance in adherence to SCBs. Gender and having an anaphylaxis management plan were also found to explain variance in adherence behaviours (all ps<.OS). The application and investigation of psychological model constructs proved useful in this population of food allergic individuals and identified targets for future interventions. The results show a strong beneficial link between adherence and possessing a management plan and provide evidence for promoting their use in food allergic individuals. Interventions designed to elicit personal barriers to adherence and address perceptions of severity surrounding food allergy may be more effective than a focus on knowledge and practical ability in improving adherence to SCBs.

This thesis investigates the relationship between quantitative correlates of diffuse brain damage and neurological and psychiatric manifestations in Systemic Lupus Erythematosus (SLE). A group of 37 patients with a primary diagnosis of SLE (mean age 43.97±12.SS) were compared to 29 matched healthy controls. The SLE group were subdivided into those who had experienced neuropsychiatric (NP) manifestations (NPSLE - n=lS) and those who had never had NP manifestations (non-NPSLE). Participants completed a broad cognitive test battery, neuropsychological measures and quantitative MRI (magnetisation transfer (MTI) and diffusion tensor imaging (OTI)). From MTI the magnetisation transfer ratio (MTR) was measured, which can be a marker for demyelination. Using OTI the extent (apparent diffusion coefficient) and directionality (fractional anisotropy) of diffusion were assessed, which are sensitive measures of brain structural integrity. Results indicate that both SLE groups had significantly higher scores on depression and anxiety and lower quality of life compared to healthy controls. The only difference between the NPSLE and non-NPSLE groups was lower physical health related quality of life in the former group. On cognitive tasks the NPSLE group scored significantly worse than controls on multiple domains, and worse than the non-NPSLE group on memory and speed of processing. There were no differences between the non-NPSLE patients and controls. On OTI measures the NPSLE group showed increased white matter ADC and a non significant decrease in FA, changes which are consistent with subtle brain damage in this group. The non-NPSLE group had higher ADC than controls if measured in the whole brain. There were no differences on MTI and few differences on measures of brain volume, suggesting demyelination and atrophy were not noteworthy in this cohort. Correlations were assessed between cognition and the other factors. In the NPSLE group cognitive function correlated with white matter FA suggesting this was driven by changes in brain parenchyma. Cognitive function also correlated with pain, fatigue, physical health, disease activity and anxiety scores suggesting general health related factors also play a role in cognitive dysfunction. In the non-NPSLE group processing speed correlated with depression scores, but no other relationships were evident. The role of anti-phospholipid antibodies, anti- Ro antibodies, corticosteroid dose and confounds such as renal involvement in SLE, hypertension and motor speed differences were considered. None of these factors could explain cognitive dysfunction in the patient group. These findings are interpreted as indicating that cognitive performance in NPSLE is unlikely to be driven by emotional health. Instead performance related to white matter integrity and general illness, two factors which may be interlinked.

Staphylococcus aureus is a leading cause of healthcare associated infection. Efforts to reduce the burden of S. aureus infections in healthcare settings have targeted patient carriage and preventing person-to-person transmission. These measures have only been partially successful. Our understanding of S. aureus transmission is limited by low discrimination of currently available typing techniques. The high resolution offered by whole-genome sequencing (WGS) has the potential to overcome these limitations. Work undertaken in this thesis exploits recent advances in WGS to understand S. aureus transmission in health care settings and in so doing establish the potential for WGS to replace current typing systems in infection control practice. The first study compares conventional approaches and WGS to investigate an outbreak of Methicillin Resistant S. aureus (M RSA) blood stream infections in a single UK hospital. By WGS, isolates within the EMRSA-16 lineage (one of the two dominant nosocomial MRSA lineages) showed strikingly low genetic diversity demonstrating the emergence of a clonal variant. This clonal variant, indistinguishable from the ancestral strain by conventional typing, accounted for 89% ofEMRSA-16 bacteraemia isolates at the outbreak hospital from 2006 and was associated with greater neutrophilia (p<0.00 1) compared with infection caused by other strains. Investigation of local and national S. aureus collections revealed the presence of isolates highly related to the variant in other hospitals across England, suggesting spread across large geographical areas. This represents the first report of a clonal variant being associated with an outbreak and provides novel insight into the epidemiology and population structures within dominant S. aureus lineages. The second study investigated the role of colonised patients as the source of new S. aureus acquisition in a hospital setting. Over 14 months all patients admitted to an adult intensive care unit were assessed for carriage, acquisition and their role in transmission. Among 680 patients where two or more serial samples were available only 44 acquisitions were observed. Isolates were available for genetic analysis from 37 acquisitions and among these only 7 (18.9%) could be explained by patient-topatient transmission. WGS disproved 3 transmission events indicated by conventional methods (spa-typing combined with overlapping patient stay) and also revealed 4 transmission and 2 acquisition events.

The Cancer Stem Cell (CSC) hypothesis has provided a novel theory of tumorigenesis by suggesting that mechanisms of organogenesis in developmental processes may be aberrantly active in neoplasms. This hypothesis proposes that CSCS within a tumour play the role of stem cells in a tissue. This novel approach not only leads to new insights into the origination of cancer, but also suggests that CSCs may be responsible for the resistance of several cancer types to current therapies. Thus, CSCs may also be targets for novel therapies. This study interrogates the proposed role of Glioma Stem Cells (GSCs) in radioresistance of glioblastoma (GBM), and specifically addresses the cell cycle checkpoint responses of GSCs to ionising radiation (IR). The aims of this project are: to generate GSC cultures from primary and established GBM cell lines, to examine the radiosensitivity of GSCs, to investigate cell cycle and proliferation dynamics of GSCs and to investigate differential cell cycle checkpoint responses of GSCs to IR. In this study, a panel of glioblastoma cell lines was used, which included primary tumour cultures as well as established cell lines. Populations were enriched for GSCs by culturing as neurospheres in serum-free medium, or depleted of GSCs by culturing as adherent monolayers in serum- containing medium. Using flow cytometry, changes in the cell cycle progression of GSCs and non- stem glioma cells (NSGCs) after IR were compared. In contrast to previously published reports, GSCs did not show preferential activation of the G2-M checkpoint. However, in the 3 cell lines studied, GSCs exhibited earlier re-entry to mitosis than NSGCs. Results for G1-S arrest varied between the cell lines. To identify potential mechanisms for the early resumption of the cell cycle in GSCs, expression and phosphorylation of checkpoint proteins and the mitotic entry promoter Plk1 were investigated. The most likely explanation for the early G2/M checkpoint recovery in GSCs was reduced phosphorylation of Chk1. This hypothesis was validated by inhibiting Chk1, which led to an earlier release from IR-induced G2/M arrest in NSGCs, but did not change mitotic re-entry in GSCs. This study presents the first direct investigation of the effects of ionising radiation on cell cycle progression of CSCs. It also provides a detailed comparison of dynamic changes in radiation induced phosphorylation of checkpoint proteins in populations of GSCs and NSGCs. The novel observation that GSC show early release from the G2/M checkpoint is supported by reduced phosphorylation of Chk1 in these cells.

At least six asthma-specific measures of health-related quality of life (HrQoL) exist. It is unclear what concepts of “quality of life” these instruments assess, how they compare psychometrically and what patients think of them. A structured review of six of these questionnaires found that they differ in almost all criteria considered (conceptual model, reliability, validity, interpretability, patient burden, translations). A mini version of the Juniper Asthma Quality of Life Questionnaire (Mini AQLQ-J) and the Sydney Asthma Quality of Life Questionnaire (AQLQ-S) were psychometrically analysed, using data from an adult asthma trial (n=146). Strong correlations with asthma symptoms and asthma control suggest that the measures may not measure a distinct quality of life construct.

Eighteen per cent of the UK population have cognitive impairment and 1/3 of older people have chronic kidney disease (CKD). There is a high prevalence of white coat hypertension (WCH) in this population. Observational studies have associated lower BP with poor cognitive function. In the CKD population lower BP has been associated with increased mortality and cardiovascular events. Lowering BP might adversely affect cognitive function. Aims: To describe associations between ambulatory blood pressure measurements (ABPM), white coat effect (WCE) and cognitive function and to determine if carotid atherosclerosis contributes to this association. Quantitative MRI will be used to analyse structural correlates for adverse cognitive performance and to ascertain if quality of life (HRQOL) is affected by lower ABPM.

Dialysis in patients with kidney disease is associated with cognitive decline. The reasons for this are multifactorial but in haemodialysis (HD) patients it is postulated that paradoxical embolisation of material from the extracorporeal circuit may occur across a right-to-left shunt, such as a patent foramen ovale (PFO), and cause cerebral damage. We aimed to identify the prevalence of PFO in dialysis patients and to assess for evidence of cerebral microembolisation during HD and continuous veno-venous haemofiltration (CVVH). We also wished to correlate the presence of PFO with rates of cognitive decline.

Alcohol-related liver disease (ARLD) refers to the spectrum of hepatic pathology arising from excessive alcohol consumption. In contrast to most of continental Europe, where the incidence is falling, ARLD is a growing clinical problem in the UK and currently accounts for ten percent of all deaths occurring between 40 - 49 years of age. Severe alcoholic hepatitis (AH) is arguably the most florid manifestation of ARLD, presenting with jaundice and features of hepatic decompensation, often in those without an existing diagnosis of liver disease. Despite abstinence short-term mortality approaches 40%, which may be improved by early diagnosis and timely medical therapy. Among current controversies in the management of severe AH are the necessity for liver biopsy to confirm the diagnosis, and hence there is a recognised need for non-invasive diagnostic aids. Corticosteroids have remained the mainstay of therapy for over 30 years, although a significant minority fail to respond and are particularly susceptible to infections as a consequence of treatment. A means of prospectively and non-invasively identifying these individuals would be a significant advancement.

Tuberculosis is endemic in the Gambian population, in which the magnitude of mycobacterial antigen-driven interferon-γ (IFN-γ) response in BCG vaccinated neonates has been linked to regions on the genome that encode the RIP2 kinase, the toll-like receptor 4 adapter protein MD-2 and the NF-κB subunit NF-κB2 by genome-wide linkage analysis. The receptor interacting protein (RIP2) is an essential kinase downstream of the nucleotide-binding oligomerization domain-containing protein 1 (NOD1) and NOD2, both intracellular pattern-recognition receptors for peptidoglycan moieties that induce activation of NF-κB. To establish the significance of RIP2 kinase during Mycobacterium tuberculosis infection, RIP2 was depleted in THP-1- derived macrophages using small interfering RNAs. In the absence of RIP2, THP- 1-derived macrophages secreted significantly reduced levels of the proinflammatory cytokine IL-1β upon infection with M. tuberculosis.

Patient organisations are often characterised in sociological literature as patient representatives, speaking for people affected by an illness in medical, political and scientific spheres. Using Motor Neurone Disease and Parkinson’s organisations as case studies, I investigate the challenges faced by patient organisations attempting to fulfil this role, focusing in particular on the need to balance responsibilities associated with care and campaign functions and increasing engagement in research. The principal focus of this PhD is to examine different conceptualisations of representativeness that have been discussed overtly and implicitly by participants. I have examined the extent to which patient organisations represent their members’ needs and cultivate a sense of collective identity, the way in which the patient organisations represent their members during the setting of research agendas, and finally I have considered the extent to which representation coincides with the concept of patient involvement.