Chronic Kidney Disease (CKD) is common and often has a major impact on the health of those affected. In this thesis I have focused on areas of uncertainty that may have major implications for patient care. Firstly, I assessed the determinants of increased mortality in a multi-ethnic primary care population. Secondly, I investigated the differential progression of CKD between ethnicities. Thirdly, I assessed if tryptase, as a marker of mast cell activation, could be used to stratify risk in CKD. Finally, I investigated the impact of CKD on health related quality of life (HRQL) and the association between HRQL and clinical end-points. I found that: (i) comorbidity has a profound impact at a population level on survival in CKD; (ii) albuminuria is the principle modifiable risk factor for progression to end-stage renal disease (ESRD) in people of South Asian ethnicity; (iii) serum tryptase is an independent prognostic factor for ESRD in patients with CKD receiving treatment with an ACEi or ARB; and (iv) Low HRQL is common in CKD and reduced HRQL is associated with a higher risk for death. The findings from this thesis contribute to the understanding of CKD in ethnically diverse, high-risk populations and form the basis for further studies.

Home Treatment for acute psychiatric illness was compared to conventional hospitalisation in a design which focused on completed episodes of either exclusive alternative. The evaluation was conducted with the West Birmingham Home Treatment Team and All Saints Hospital, Birmingham. Forty cases in each group were examined with closely equivalent sociodemographic features and previous psychiatric history. The length of treatment, clinical outcome, identification and targeting of needs, readmission profile and client satisfaction were compared. The study focused on presentations involving mainly a diagnosis of severe mental illness. Home Treatment was significantly shorter and involved wider targeting of identified needs. There was no significant difference in terms of clinical outcome. Home Treatment and avoidance of admission were preferred by patients. The determinants of satisfaction with acute care in both settings was explored qualitatively. Significant design and sampling problems limit the generalisability of results. The case for and against Home Treatment is examined. The lessons learnt during the course of the study regarding the appropriate focused evaluation of Home Treatment and the place of Home Treatment as a particular model of intensive care are critically discussed.

Current methods to study enhancers in vivo involved integrating DNA sequences into the genome in a random position, in zebrafish the transposase Tol2 is utilised. However, this random genome integration can result in position effects which cause variations in reporter gene expression patterns preventing conclusions from being drawn about the enhancer being tested. To address the issue of variable position effects when using random integration techniques to study enhancers, this project aimed to establish a PhiC31 integrase system of targeted transgenesis in zebrafish. Firstly, we designed and tested a multicomponent system including a recipient vector, donor vector and PhiC31integrase mRNA. These components were co-injected into one cell stage embryos to test the integration function of PhiC31 integrase in zebrafish. The integration was detected by designing the recipient and donor vectors such that a switch from GFP to mCherry lens expression marks embryos with legitimate recombination. Over 97% of fluorescent embryos showed mCherry expression in the lens after coinjection of the three components indicating that integration of the two vectors by PhiC31 integrase is highly efficient. Legitimate recombination was shown to have occurred using PCR and sequencing techniques from total RNA extracted from embryos. A recipient transgenic line was made into which the donor vector and PhiC31 integrase RNA were co-injected. This resulted in around 70% of fluorescent embryos showing mCherry expression in the lens which suggests targeted genome integration is also efficient in zebrafish embryos. To establish whether variability of positional effects could be reduced using this system, an enhancer-promoter-reporter construct was modified to ii include donor vector sequences and injected into recipient line transgenic zebrafish embryos. Expression patterns observed in stable lines made with either Tol2 transposase or PhiC31 integrase suggest that variability in position effects is reduced when using the PhiC31 integrase system. Together, these results provide evidence that the PhiC31 integrase system I have tested is suitable for a number of uses in zebrafish, including enhancer screening.

Previously thought to be inert, nitrite is now deemed to be an important endogenous source of nitric oxide (NO), particularly during hypoxia and ischaemia. Largely animal and some limited human studies propose a role for nitrite in ‘hypoxic vasodilatation’ and ischaemia-reperfusion injury. One study explores the effect of systemic nitrite infusion on cardiac and peripheral haemodynamic parameters in healthy subjects, during normoxia and hypoxia. Despite a lack of observed effects in healthy subjects, a study performed in patients with heart failure during normoxia demonstrated favourable haemodynamic effects on cardiac output, albeit at high doses of nitrite. In patients undergoing coronary artery bypass surgery, low dose nitrite infusion afforded protection against ischaemia-reperfusion injury. Several mechanisms of nitrite reduction to NO have been described and remain to be fully elucidated. The role of one of these putative mechanisms, namely mitochondrial aldehyde dehydrogenase (ALDH2) was explored during normoxia and hypoxia. Ex vivo human vascular ring studies confirmed ALDH2 as an important nitrite reductase, in contrast to in vivo observations in the forearm vasculature, suggesting that numerous mechanisms are involved in vivo which are harder to isolate. Furthermore, this hypoxia vasodilatory role was not replicated in with GTN in the human forearm vasculature.

Self-monitoring blood pressure (SMBP) has been shown to more accurately estimate true underlying BP but it is unclear how commonly it is practiced in the UK and why patients engage in this behaviour from a psychological perspective. A survey was first sent to primary care patients with hypertension (n=955) in the West Midlands, UK to establish the prevalence of SMBP. Secondly, interviews with respondents (n=16) combined with a review of previous empirical research informed the design of an in-depth questionnaire sent in the final stage of the study (n=236) to confirm the investigative associated factors. A third of the survey population 293/955 (31%) reported SMBP which was predicted by education, self-efficacy and doctors’ health locus of control (DHLOC) (p<0.01). Age and negative outcome expectations about SMBP potentially moderated this relationship. A lack of available guidelines and poor communication with the General Practitioner (GP) about self-monitoring however resulted in a negative perception about whether engaging in SMBP had any real benefit. Self-monitoring was practiced by an appreciable minority in the UK, potentially enabling patients to gain control over managing their own BP. Better education and shared decision making between the patient and the GP might remove negative perceptions about SMBP ensuring its long term practice.

Neurotrophins are neuromodulatory proteins utilised within neuronal networks for development and survival. Based on previous evidence revealing the expression of neurotrophin components in immune cells, the present study investigates neurotrophin component expression within Burkitt’s Lymphoma B cells. Different latency stages within Burkitt’s Lymphoma B cells are observed due to the expression of resident EBV latency genes. These B cells are said to display germinal centre B cell markers and interact with other cells within a germinal centre environment, such as Follicular Dendritic Cells (FDCs) and T cells. EBV latency phenotypes were characterised for the lines used here; these lines were then screened for the expression of neurotrophin ligands and their receptors: the selective high affinity Tropomyosin receptor kinases TrkA, TrkB and TrkC and the (common) low affinity, tumour necrosis factor receptor member, p75NTR. FDC-like cell lines were also analysed for neurotrophin component expression. This was to question FDCs as potential providers of paracrine neurotrophin signalling to Burkitt’s lymphoma B cells. Neurotrophin and neurotrophin receptor expression was detected by flow cytometry, confocal microscopy, reverse transcription polymerase chain reaction (PCR) and real time PCR methods. Cell lines with the full complement of EBV latency genes expressed were positive for the neurotrophin, Brain Derived Neurotrophic Factor (BDNF) and all neurotrophin receptors in question. Burkitt’s lymphoma cells expressing limited EBV latency genes revealed more restricted expression of neurotrophin components. FDC-like lines also express neurotrophin and neurotrophin receptors, thus paracrine signalling between Burkitt’s lymphoma cells and FDCs may occur via this axis, perhaps to enhance B cell survival.

Patient experience of serious ADRs and their impact on patients’ lives have not been previously explored. This thesis aims to explore the experiences of patients diagnosed with drug-induced Stevens-Johnson syndrome (SJS) and Toxic epidermal necrolysis (TEN). In addition, the very elderly are a group particularly vulnerable to ADRs, and in particular, those due to antihypertensives. This thesis thus also explores the impact of such ADRs in the elderly, on managing their hypertension optimally. Firstly, I undertook a retrospective qualitative study of adult survivors of SJS and TEN, to explore their experiences, views and perceptions. The ADR continued to affect patients’ lives long after the event. Their interpretations regarding why the ADR occurred differed and may have influenced their trust in healthcare professionals and in medicines. Clear communication, and patient education and support after the event, may therefore be important. Secondly, I undertook an analysis of internet-based personal descriptions of SJS and TEN. Authors wished to share experiences and seek advice from others, and had common concerns regarding the ADR. These findings could be used to improve the management of such patients. Finally, I undertook a retrospective cohort study in very elderly patients to determine whether ADRs to antihypertensive drugs limit the clinician’s ability to achieve blood pressure targets. Almost half the patients studied had documented ADRs which limited further intervention. Aggressive treatment of hypertension in the very elderly may therefore be difficult to achieve in practice.

NAFLD is characterized by simple steatosis, which can progress to chronic inflammation and fibrosis. Vascular Adhesion Protein-1 (VAP-1) is an adhesion molecule with semicarbazide- sensitive amine oxidase (SSAO) activity, which is also expressed as a soluble protein in serum (sVAP-1) and elevated in inflammatory liver diseases such as NAFLD. VAP-1 has been shown to modulate glucose and lipid uptake in muscle and adipose tissue and thus we investigated whether it may contribute to glucose and lipid homeostasis in human liver tissue. Recreating the multicellular liver environment using an ex-vivo model we have shown that activation of VAP-1 by its substrate methylamine leads to activation of NF-κB, glucose uptake and lipid accumulation in the human liver with changes in transporter expression of GLUT4, GLUT10 and GLUT13, as well as FABP2, LRP1, FATP2, FATP3, FATP4 and FATP6. We have also documented changes in transporter expression profiles in human disease. In conclusion, we demonstrate for the first time global alterations in cellular expression of glucose and lipid transporter proteins in NASH. We confirm that VAP-1 is elevated in disease and that SSAO activity of VAP-1 results in enhanced hepatic glucose and lipid accumulation with changes in transporter expression. Thus we propose that bioactive metabolites of SSAO activity contribute to the metabolic derangement evident in fatty liver disease.

Despite major advances in therapies, chronic heart failure (CHF) and hypertrophic cardiomyopathy (HCM) are still associated with significant morbidity and mortality. These patients often have a significant limitation in their exercise capacity. We showed that there are widespread abnormalities of both systolic and diastolic function in HCM patients. These abnormalities contribute significantly to exercise limitation observed in these patients. Furthermore, we showed that HCM manifest a myocardial energy defieciency which was accompanied by a slowing of the energy-dependent early diastolic LV active relaxation during exercise. The present study supports the hypothesis that HCM is, at least in part, a disease of energy deficiency. Consistent with this hypothesis, we showed that metabolic modulation by perhexiline augmented myocardial energetics, and normalised diastolic ventricular filling which translated into significant subjective (improved symptoms) and objective (increased exercise capacity [peak VO2]) clinical improvement in HCM patients. These findings suggest that metabolic modulators, such as perhexiline, have the potential role in the management of patients with symptomatic non obstructive HCM, a condition for which there are currently limited therapeutic options. However, large scale longterm studies are still required to examine the effects of these agents on morbidty and mortality in these patients.

Contemporary pacemakers allow quantification of atrial high-rate episodes (AHREs) and atrial fibrillation burden (AFB) accurately. It is generally believed that left atrial (LA) remodelling may precede the development of atrial arrhythmias (AA), and AHRE precede the clinical manifestation of atrial flutter or fibrillation. However, the relationship between LA remodelling with AHRE has not been studied. Furthermore, the relationship of AFB to progressive LA remodelling and how this relates to indices of thrombogenesis is unclear. The aim of my study is to investigate the inter-relationship between LA remodelling, AA burden and indices of thrombogenesis in patients with pacemakers. My findings suggest that the incidence of AHRE was 35%. Increased frequency of right ventricular pacing is associated with LA enlargement and reduced global left and right ventricular function. However, there was no clear association between the right atrial pacing with cardiac remodelling. The cumulative percentage right ventricular pacing and increased LA volume are associated with the development of AHREs, but AFB is independently associated with changes in LA function, left ventricular diastolic function and indices of platelet activation and thrombosis. In addition, I demonstrated the feasibility and reproducibility of a novel method of IACT measurement in patients with permanent pacemakers.