Diabetes mellitus (DM) is a major health problem currently affecting over 225 million people worldwide. It is often described as a major metabolic disorder, which can result in numerous long-term complications including retinopathy, nephropathy, neuropathy and cardiomyopathy. DM is due to a deficiency of insulin or insulin resistance. Of the 225 million diabetic patients, around 5-10% suffer from type 1 DM (T1DM) and the remaining 90-95% suffer from type 2 diabetes (T2DM). T1DM is due to insulin deficiency whereas T2DM is due to either a reduction in insulin secretion or insulin resistance. Patients with both T1DM and T2DM normally require insulin and hypoglycaemic drugs, respectively. Changes in life style habits, regular exercise and healthy diets can also help to control blood glucose in T2DM patients. Mediators that can help to increase the health of pancreatic islets to synthesize and secrete insulin will be of tremendous benefit to diabetic patients. This study investigated the beneficial effects of incretins, substances such as glucagon-like peptide-1 (GLP-1) and its synthetic agonist, exenatide on the diabetic rat pancreas compared to healthy, agematched controls. These incretins exert their beneficial effects by repairing the pancreatic islets. Thus, increasing pancreatic beta (β) cell mass and in turn it will help to synthesize and secrete insulin into the circulation. The rationale of this study was to find out how these two incretins can improve insulin secretion both in vivo and in vitro employing the rat model of T1DM following injection with streptozotocin (STZ). The project employed six groups of rats, with three groups serving as age-matched, healthy controls and the other three groups rendered diabetic. One set of rats from each group was untreated while the rats from the other four groups were given either GLP-1(50 nmol/kg body weight) or exenatide (1 μg/kg body weight) over 10 weeks. The project measured body weight, levels of blood glucose and insulin. The plasma levels of liver and kidney markers were also determined. The in vitro study measured insulin secretion from pancreatic fragments, the distribution of insulin- and glucagon-positive cells in pancreatic islets, granules, co-localization of different peptides in the islets, biochemical, and molecular biological changes, which may occur in the pancreas during the experimental period. For the in vivo study, the results have shown mild gain in body weight and no change in blood glucose levels in both treated and untreated age-matched normal control rats. Furthermore, the results show a significant reduction in blood glucose levels in diabetic rats treated with either GLP-1 or exenatide, but the beneficial effect was more pronounced following GLP-1 treatment. The results also show no changes in glucose handling between normal treated or normal untreated rats following blood glucose tolerance test (GTT). However, in diabetic rats, the results show that the GTT reveals a better glucose tolerance in these diabetic animals treated with either GLP-1 or exenatide but the effect was more significant with GLP-1 compared with untreated diabetic rats. The present study shows that diabetic rats secreted significantly less insulin in the blood than normal healthy rats and a significant increase in serum insulin was detected in both normal and diabetic rats treated with either GLP-1 or exenatide compared to untreated controls. The results also show significant reductions in the liver enzymes, aspartate transferase and alanine transferase in the diabetic rats. A similar beneficial effect on kidney function was obtained owing to a small reduction in blood urea nitrogen, serum creatinine and serum uric acids in both normal and diabetic rats treated with either GLP-1 or exenatide. In the lipid profile study, the results show a mild reduction in serum cholesterol and a marked reduction in serum triglyceride in both normal and diabetic rats treated with either GLP-1 or exenatide. The results from the in vitro study show that either GLP-1 or exenatide can evoke marked dose-dependent release (secretion) of insulin from pancreatic tissue fragments of normal and diabetic rats, indicating that there is a clear role for either GLP-1 or exenatide in inducing insulin secretion. In this study, an attempt was also made to investigate both the number and distribution of endocrine cells in the control and diabetic rat pancreas using immnohistochemistry. The results show a significant increase in the number of cells containing either insulin or GLP-1 in both normal and diabetic treated rats. However, in the case of exenatide, catalase and glutathione reductase-positive cells were only significantly increased in diabetic rats, but the increase was not significant in normal rats treated with either GLP- 1 or exenatide. These results show that the significant increase in number of catalase and glutathione-positive cells in diabetic rats treated with either GLP-1 or exenatide reveal the beneficial antioxidant effect of both GLP-1 and exenatide in treatment of oxidative stress, which usually occurs in DM. On the other hand, there was a significant decrease in glucagon-positive cells in both normal and diabetic rats treated with either GLP-1 or exenatide. The immunohistochemical and immunofluorescent studies also revealed that insulinpositive cells were distributed both in the central and peripheral portions of the islets of Langerhans in normal pancreas. In contrast, glucagon-positive cells were located in the peripheral part of the islets of Langerhans. After the onset of diabetes, the number of insulin-positive cells was reduced significantly. In contrast, the number of glucagonpositive cells increased significantly with abnormal pattern of distribution compared to normal pancreas. The pattern of distribution of both GLP-1 and exenatide has indicated co-localization not only with insulin, but also with glucagon. Furthermore, catalase and glutathione reductase-positive cells were distributed homogenously all over the islet of Langerhans with no specific co-localization with specific type of endocrine cell. In the gene expression study, the results show significant increases in the levels of mRNA of pancreatic duodenal hoeobox-1, heat shock protein-70, glutathione peroxidase, insulin receptor and glucagon like peptide-1 receptor in both normal and diabetic rats treated with either GLP-1 or exenatide. However, the increase was not significant in mRNA gene expression of either insulin receptor or glucagon like peptide-1 receptor in normal rats treated with GLP-1. On the other hand, the gene expression results show that glucagon mRNA level was significantly decreased in both normal and diabetic rats treated with either GLP-1 or exenatide. In conclusion, the results of this study have clearly demonstrated that both GLP-1 and exenatide have marked beneficial effects on pancreatic islet cells, especially β- and α- cells, which produce insulin and glucagon, respectively. The two incretins seem to repair the diabetic pancreas, which in turn secretes more insulin and less glucagon.

Emergency Medical Services (EMS) play a pivotal role in any healthcare organisation. Response and turnaround time targets are always of great concern for the Welsh Ambulance NHS Trust (WAST). In particular, the more rural areas in South East Wales consistently perform poorly with respect to Government set response standards, whilst delayed transfer of care to Emergency Departments (EDs) is a problem publicised extensively in recent years. Many Trusts, including WAST, are additionally moving towards clinical outcome based performance measures, allowing an alternative system-evaluation approach to the traditional response threshold led strategies, resulting in a more patient centred system. Three main investigative parts form this thesis, culminating in a suite of operational and strategic decision support tools to aid EMS managers. Firstly, four novel allocation model methods are developed to provide vehicle allocations to existing stations whilst maximising patient survival. A detailed simulation model then evaluates clinical outcomes given a survival based (compared to response target based) allocation, determining also the impact of the fleet, its location and a variety of system changes of interest to WAST (through ‘what-if?’ style experimentation) on entire system performance. Additionally, a developed travel time matrix generator tool, enabling the calculation and/or prediction of journey times between all pairs of locations from route distances is utilised within the aforementioned models. The conclusions of the experimentation and investigative processes suggest system improvements can in fact come from better allocating vehicles across the region, by reducing turnaround times at hospital facilities and, in application to South East Wales, through alternative operational policies without the need to increase resources. As an example, a comparable degree of improvement in patient survival is witnessed for a simulation scenario where the fleet capacity is increased by 10% in contrast to a scenario in which ideal turnaround times (within the target) occur.

There is a continuing need for improvements in the cryopreservation of clinically relevant cells, tissues and organs as advances in transplantation science and regenerative medicine rise alongside an aging populace that intensifies demand. Antifreeze (glyco)proteins (AF(G)Ps) and antifreeze proteins (AFPs) are classes of proteins found in cold acclimatized species. Ice recrystallization is a highly damaging process that occurs upon the thawing of frozen specimens with AF(G)Ps and AFPs limiting this effect in a process termed ice recrystallization inhibition (IRI). However AF(G)Ps and AFPs largely fail to improve in vitro and ex vivo cryopreservation due to their secondary property of dynamic ice shaping. The biocompatible and synthetically accessible polymer poly(vinyl alcohol) (PVA) has been shown to process a strong IRI activity. The IRI property of PVA along with numerous other polymers and polyols is investigated to highlight the uniqueness of PVA (Chapter 2). PVA is then explored as a cryoprotectant with red blood cells (Chapter 3), immortalized mammalian cell lines (Chapter 4) and primary cells (Chapter 5) with a significant advantageous effect observed with each cell type in terms of the number of cells recovered post thaw. However, this is despite the use of proportionately low concentrations of PVA compared to traditional membrane permeable cryoprotectants. The application of PVA as a cryoadjuvant could therefore improve the cryopreservation of cells, tissues and organs resulting in widespread clinical benefits.

Leveraging purchasing power through collaborative purchasing arrangements is widely used to deliver efficiency savings in public procurement. The success of such arrangements requires the purchasing behaviours of individual members of the collaborative organisation to change in order to realise the benefits of lower prices. However the actual purchasing behaviours of organisations within a collaborative purchasing arrangement have not been widely researched. The research uses a stationary stochastic model of buyer behaviour, the NBDDirichlet, to describe and predict the purchasing behaviours of buyers of coronary and ureteral stents in a collaborative purchasing organisation in the English National Health Service. The three year analysis period is a period of major change for each category, the result of supplier promotional activity in the ureteral stent case and purchasing management activity in the case of the coronary stents. Deviations between the observed patterns of behaviour and the model predictions point to violations of the basic Dirichlet requirements of stationary markets and lack of partitioning. In both the ureteral and coronary stent cases the research identifies a segment of frequent purchasers whose behaviour differs from the rest of the population. The impact of framework agreements in restricting the purchasing repertoire of buyers is also identified as a deviation from typical purchasing patterns. Both interventions result in changes to established loyalty patterns, whereby the initial high observed levels of loyalty towards particular suppliers are replaced by a greater willingness to purchase from alternative suppliers. The data analysis also provides preliminary evidence for purchase deceleration as buyers defer purchases during a negotiation period in anticipation of improved pricing.

Background: Literature indicates underutilization of Palliative Care Services in the UK, with possible inequalities of access. These trends in underutilization are seen in Adult-Palliative Day-Care (APDC), a Specialist Palliative Care Service delivered in the outpatient setting. However, gaps in knowledge remain regarding if underutilization in APDC is real, and the identity and nature of the factors which determine access. Aim: The overall research question was “What are the factors which act to determine access to APDC?”. Five sub-questions for exploration in the context of access were formulated relating to the: perceived health care needs of users; the benefits of using APDC, and understandings of the role of APDC as a palliative care service. Methods: The study site was a cancer network in the Midlands of England which covered rural and urban areas. It contained 5 APDC units, 3 Primary Care Trusts, and 3 Acute Care Trusts. Fifty semistructured in-depth interviews were conducted with: 19 providers of APDC; 13 health professional referrers; 11 palliative care patients who had used the service; and 7 of their carers. The reasons for non-attendance for 149 patients who were referred to day-care but did not attend were also analysed. Thematic analysis with constant comparison and content analysis were used to analyse transcripts and document data respectively. Results: Eighteen determinants of access were identified arising out of the characteristics of the: potential service user (2), the health service or organization (9), and from interactions between potential service users, the family, the wider society, and the health service (7). The study found that utilization measures in APDC may not be accurately representing service use, as APDC units maybe functioning at their maximum capacity while current calculation methods report underutilization. Conclusion: New insights into accessing APDC are presented which and may have applications for future policy and research.

It is now widely acknowledged that spatial structure and hence the spatial position of host populations plays a vital role in the spread of infection. In this work I investigate an ensemble of techniques for understanding the stochastic dynamics of spatial and discrete epidemic processes, with especial consideration given to SIR disease dynamics for the Levins-type metapopulation. I present a toolbox of techniques for the modeller of spatial epidemics. The highlight results are a novel form of moment closure derived directly from a stochastic differential representation of the epidemic, a stochastic simulation algorithm that asymptotically in system size greatly out-performs existing simulation methods for the spatial epidemic and finally a method for tackling optimal vaccination scheduling problems for controlling the spread of an invasive pathogen.

Mass spectrometry is an analytical technique which is used extensively in the fields of chemistry and physics. Developments in the field over the last two decades have permitted the analysis of a wide variety of biological molecules from a range of sources. The term proteomics relates to the study of the protein complement of a cell or organism with particular interest in the identification and quantification of these analytes. A biomarker is a characteristic that can be measured and evaluated to give an indication of normal, biological processes, or pharmacological responses to a therapeutic intervention. Bodily fluids are a rich source of potential biomarkers as they can be obtained in reasonable quantity and their extraction is generally minimally invasive. The plasma proteome, which contains many thousands of analytes spanning a dynamic range greater than 10 orders of magnitude, reflects the status of the many tissues and organs in the body serving as an ideal medium for potential biomarker discovery. The analytical challenges posed by the plasma proteome are significant. Depletion of the highly abundant proteins is usually a prerequisite of any biomarker study and no technique has the dynamic range to study all of the proteins present. Comprehensive characterisation of the plasma proteome requires significant experimental effort and cost. Use of pooled samples in biomarker studies is widespread and the majority of biomarkers, which have been identified in the discovery phase, have not passed clinical validation. A data independent, label-free quantitative approach has been evaluated for the study of depleted maternal plasma proteomes taken in the first trimester. Plasma was characterised from individual and groups of patients from three obstetric conditions using single and multi-dimensional chromatography. Potential biomarkers from each source were identified and evaluated. Multi-dimensional chromatography was used to simplify the complexity of the analytes introduced to the mass spectrometer and the benefits and limitations of the approach in terms of biomarker discovery have been demonstrated.

Background Virtual patients (VPs) are computerised online representations of realistic clinical cases. Recent technology and software advances position VPs as a standardised, accessible, collaborative teaching tool. We do not know how they should be designed. My research question is: how do different VP design principles influence student experiences when completing VPs? The aim of this study is to provide qualitative and quantitative research evidence to support VP design and development. Methods This research project uses qualitative and quantitative methods to evaluate how VP design influences medical student learning, based on groups of students from three UK medical schools (Warwick, Birmingham, Keele). The initial qualitative research component is a grounded theory (GT) focus group study evaluating VP design properties. The literature review and qualitative research identified the two most important VP properties to research were: (1) branching within the cases; and (2) structured clinical reasoning instruction (SR) intended to promote good clinical decision making in the VPs. The quantitative research component is a multi-centre randomised experimental 2x2 factorial study of undergraduate students at three UK medical schools, conducted to a published protocol. I investigate two most important independent VP design variables: (1) branching, present or absent; (2) SR, present or absent. Outcomes including: (a) VP scores; (b) VP student evaluations; (c) metrics collected from the VP environment; (d) student self-reported case preferences and (e) summative assessment results. The study has institution ethics approval. Results In the qualitative study of six focus groups (n=46), I produced a model describing how VP design influences learning. In the quantitative research, 572 students completed 1773 VPs, and 1223 evaluations, with 296 (50.1%) students completing all four VPs (1184). Key findings were: student expressed preferred SR when present (70.5% of student, P<0.001); there were no significant differences in adjusted global VP scores or evaluation scores (all p>0.3 for the independent variables); institution factors played an important role with higher scores at one centre (p<0.001); and there were significant improvements in Bayesian reasoning with SR present (7% improvement, p<0.001). Discussion This original research is the first GT study into VPs. The quantitative component is the largest study to date in the literature exploring VP design variables. It provides practical lessons for authors and institutions for design and delivery of VPs. All VPs used are available as open education resources.

Cardiac arrest in paediatric patients often results in death or survival with severe brain injury. Therapeutic hypothermia, lowering of core body temperature to 32 to 34⁰C may reduce injury to the brain in the period after circulation has been restored. This thesis comprises studies related to the feasibility of performing a randomised controlled trial (RCT) of therapeutic hypothermia for neuroprotection after cardiac arrest in the UK. A systematic Cochrane review of paediatric evidence finds no published RCTs supporting or refuting the use of therapeutic hypothermia after cardiac arrest. Four on-going RCTs are identified which will add to the future evidence base; however, a future UK RCT is recommended. Additional support for a RCT is demonstrated by two UK surveys of paediatric intensive care and emergency care clinicians. Current UK practice is varied and clinical equipoise exists regarding post cardiac arrest temperature management. A national, retrospective study of all admissions to paediatric intensive care after out of hospital (OHCA) and in hospital cardiac arrest (IHCA) shows an overall survival of 76 and 50% respectively. Important differences between IHCA and OHCA populations are identified, recommending separation in a RCT. The incidence rate of cardiac arrest admissions to PICU in the UK is too low to recruit to a UK only RCT, after consideration of sample size requirements. A large, multi-centre, retrospective, observational study of OHCA patients identified multiple factors associated with survival. A survival prediction model, incorporating: pupillary reaction, blood lactate level and duration of cardiac arrest, is described. The model could be used as a tool for stratified randomisation within a RCT. Finally, therapeutic hypothermia is retrospectively compared with standard, normothermic temperature management after OHCA. In a limited population, no difference in survival is found; however, important information on application, logistics and safety of the intervention are evaluated.

Cerebral palsy (CP) affects around every one in 500 children born. It isn’t a particular illness or disease, but an umbrella term used to describe a physical condition that affects movement as a result of injury to the brain. There are several types of CP, the main ones being spastic, athetoid and ataxic. Despite medical advances, there is no cure for CP but there are ranges of treatments from drugs to Botulinum toxin type A injections, massage therapy to surgery. The aim of this study is to look at two of these treatments, namely Botulinum toxin type A injections and physiotherapy to treat spastic CP. Botulinum toxin is widely used to reduce muscle tone in the treatment of spasticity in children with cerebral palsy. The aim of the study is to compare the effects treatment with Botulinum toxin type A and Botulinum toxin type A with additional physical therapy in the management of a group of children with cerebral palsy. Experiments were done at The Prince Sultan Hospital and Al-Hada Armed Forces Hospital in Saudi Arabia. The local Ethics Committee approved the protocol. 47 children were recruited. All had cerebral palsy, diplegia, spasticity of the ankle planter flexors and significant gait abnormalities due to dynamic equinus foot deformity. They were divided into two groups. Both groups had their Gross Motor Function assessed one week before injection and at 4 and 6 weeks after injection. Additional measurements of range of movement and stiffness at the ankle and soleus electromyograms were recorded The soleus EMG was silent during ankle dorsiflexion in 20 children four weeks after injection of Botox. The EMG had returned six weeks after injection in every child. The Gross Motor Function Measurements were not significantly different in the two groups before the injection (p=0.23). The measurements improved significantly over the next six weeks in both groups (p<0.001). The magnitude of the improvement was greater in the group, which received Botulinum toxin type A and physical therapy (means 57.2 + 8.90 before, 64.9 + 9.78 after. Mean + SD) than in the group which received Botulinum toxin type A alone (59.5 + 11.0 before, 62.4 + 11.3 after Mean + SD). Conclusions 1. . The Treatment allocation provided groups, which were comparable pre-treatment in terms of baseline GMFM. 2. . Both treatments showed evidence of improvement in GMFM over the period of the study and particularly at 52 weeks. 3. . Treatment 2 showed a significant average advantage in GMFM over Treatment 1 at all times in the study. 4. . This advantage in average GMFM increased from 4 through to 52 weeks with a clear and significant difference between 4 and 52 weeks. 5. . This average advantage appeared to increase the higher the child’s baseline GMFM.