This thesis is comprised of three chapters written as articles for publication. The theme linking the chapters is the focus on interaction between service users and professionals working in health and care settings. Chapter one reviews discursive research on health and care professional interaction with people with a learning disability. The focus is on how professionals talk with and about people with a learning disability. Citations are explored which describe professional talk in research interviews, interactions with people with a learning disability in everyday settings, questionnaire-based interviews, therapeutic interactions and meetings. Certain practices have been found to work well in particular contexts and some not so well. There is potential to use practices across contexts, however there is no guarantee that a particular practice will perform the same action in a different interactional setting. Future research in the area could look at the effects of trying to increase the use of some of the more successful practices through staff training. Chapter two details an empirical study on how questions are used by participants in care programme approach (CPA) review meetings in the NHS. Questions were found to be asked by the professionals at the meeting in a manner that followed the format of a semi-structured interview. Six question types are described in the paper that perform a range of actions; switching topic, prompting the service user, avoiding overt disagreement, bringing the meeting back on topic, offering the service user the opportunity to ask questions and ensuring a particular structure is followed. The analysis suggests that government guidance on CPA regarding service user participation is not being realised in the way that the process is conducted on an interactional level. Chapter three contains a reflective piece about my experiences conducting discursive research in an NHS setting. It describes the challenges faced in doing research using this methodology and makes suggestions on how some of these potential issues might be tackled.

Hepatitis C Virus (HCV) infection is a hepatotropic, enveloped virus with a positive sense RNA genome. The prevalence rate of the virus has been shown to be 2.9% of the world population, equating to around 170 million infected individuals. Due to the high level of chronic infection and progressive nature of the liver disease, HCV is a major health concern. Four host proteins have so far been indicated as viral receptors; scavenger receptor BI, CD81, Claudin1 and Occludin. The interaction of CD81 and Claudin1 has been previously demonstrated which lead us to determine whether specific interactions are essential for HCV entry. Using a combination of imaging and biochemical methods we were able to demonstrate that only receptor active Claudins specifically interacted with CD81. We also evaluated the ability of previously published Claudin1 mutants to interact with CD81 and demonstrated that receptor inactive mutants no longer form an association with CD81. A bioinformatic model predicted the association of the T149, E152 and T153 residues of CD81 EC2 with the 62-66 region of Claudin1. Mutation of these residues lead to an ablation of Claudin1 association and a reduction in on HCV entry, further indicating the requirement of the Claudin1-CD81 complex in the entry process.

AcrA is the periplasmic adaptor protein component of the major efflux system AcrB-TolC of \(Salmonella\) Typhimurium. AcrA of S. \(Typhimurium\) SL1344 was inactivated and the mutant phenotype characterised. RT-PCR and western blotting were used to confirm expression of \(acrB/AcrB\) was retained in the acrA mutant. The AcrA mutant was hyper-susceptible to a range of antimicrobials and was more susceptible to some agents than strains lacking AcrB and TolC. This is partially explained by the increase in accumulation of Hoechst H33342, a fluorescent substrate of AcrAB-TolC, indicating that the inactivation of \(acrA\) resulted in reduced efflux activity. Lack of AcrA also attenuated the ability of S. Typhimurium to infect INT-407 and RAW 264.7 cells \(in vitro\) as previously published for AcrB and TolC mutants. The virulence defect of the mutants could not be rescued by addition of supernatant from an infection of INT-407 cells with SL1344 or addition of media conditioned by uninfected INT 407 cells. However, addition of media conditioned by overnight growth of SL1344 was able to ameliorate the virulence defect of the mutants. This suggests that AcrAB-TolC of SL1344 exports a factor/s required for virulence which the mutants are unable to export and that exogenous addition of this factor can restore the virulent phenotype. Inactivation of \(acrA\) conferred a phenotype distinct to that of inactivation of \(acrB\) or \(tolC\) indicating a role for AcrA distinct to that of other protein partners in both efflux of substrates and virulence

Decision-analytic models have an important role in healthcare funding decisions in the UK and internationally. However, errors have been reported in published models, which may indicate poor modelling practices, potentially leading to sub-optimal recommendations on cost-effectiveness. Little in-depth research has been undertaken to investigate the processes used by modellers in model development. The objective of this research was to explore the modelling methods used by modellers, with particular focus on problems encountered. This work involved two qualitative phases of research. In the first phase, twenty-four in-depth interviews with modellers were undertaken. Constant comparative analysis was used to compare informant practices, and identify common issues in model development. The second phase involved two separate model-building case studies with teams of modellers and clinicians. Methods of non-participant observation, qualitative interviews, and think-aloud were used to investigate model development. The findings of the case studies were compared using framework analysis. Important themes emerging from both phases of the research concerned the diversity of practices in structural development, problems with clinician involvement in modelling, and a lack of time and resources to carry out good practice methods. This work offers important recommendations for modelling practice, and suggestions for future research to improve modelling methods.

Rituximab, a monoclonal antibody directed against the human CD20 antigen, causes profound depletion of all B cells. When used in patients with autoimmune disease, IgG autoantibody titres often fall whilst serum IgG anti-tetanus toxoid antibody titres are unaffected. Antibodies of both these antibody specificities have features associated with production by long-lived CD20- plasma cells that should be resistant to Rituximab. Reasons for the differential loss of these apparently similar types of antibody were investigated. Initial experiments established multiplexed bead assays to measure, in parallel, serum titres of multiple antibody specificities. Paired acute and convalescent sera, from 11 patients treated with Rituximab for Wegener‟s granulomatosis, were then studied. During 5 months after treatment, and following clinical remission, IgG anti-Proteinase 3 autoantibody titres fell gradually. All other measured antibody titres remained little changed. These findings favour the hypothesis that autoantibody producing plasma cells are sustained by disease related inflammation. Subsequent experimental studies support a wider hypothesis -that inflamed sites can support increased plasma cell numbers. In the prolific humoral response of QM mice to immunisation with NP-Ficoll, concurrent infection with attenuated Salmonella enterica serovar Typhimurium increases splenic capacity to support plasma cells. The enhanced support may reflect locally increased IL-6 production.

This thesis incorporates five studies investigating physical activity and community mobility in individuals with multiple sclerosis (MS). 1. Pedometer step count accuracy was investigated whilst examining activity levels in individuals with neurological disease (n=43). The pedometers significantly under-estimated counts in this group. 2. The test-retest reliability of the Physical Activity Scale for the Elderly (PASE) was examined. People with MS (n=20) were found to have low activity levels with a test-retest reliability coefficient total PASE score of 0.934 (95% CI=0.62-0.97). 3. An observational study examined physical activity levels in individuals with MS using the PASE. Participants appeared to be less active than healthy individuals (69.6±50.11, 154.3±80.4 respectively). 4. A questionnaire (n=80) and focus group discussions (n=24) were used to gather user opinions regarding physical activity participation. Emerging themes were the desire to be active and the barriers and facilitators to participation. 5. A phase II RCT investigated the feasibility of a physical activity provision support system in people with MS (n=18). The approach successfully resulted in attendance at fitness centres and increased activity levels (but did not reach statistical significance). The 5 studies each present new data in the field. The implications are discussed with suggestions for further research.

Within 10 years of experiencing a deep vein thrombosis of the lower limb, up to 60% of people will be classed as suffering from post-thrombotic syndrome (PTS). The cause and risk factors for PTS are not well understood and there are no universally agreed diagnostic criteria. This thesis aimed to identify prognostic factors associated with developing PTS, the method(s) of diagnosing PTS and their relative reliability in identifying PTS. A systematic review of systematic reviews and a systematic review of primary studies was conducted to identify prognostic factors. Methods used to diagnose PTS were noted from these reviews. Prognostic factors from best evidence and methods of diagnosing PTS noted were presented to clinical experts for prioritisation via an e-Delphi study. Consensus was defined as ≥75% agreement. Fifty one potential prognostic factors and seventeen methods of diagnosing PTS were identified from the reviews and initial exploration of experts’ views. Experts reached consensus on eight prognostic factors and one method of diagnosing PTS. The prognostic factors identified can be considered for the development of a prognostic model, while the method of diagnosing PTS found to be most reliable from experts’ opinion should be considered when developing a reference standard for PTS diagnosis.

This PhD considered provision of information to potential research participants. It gathered data on the types and detail of information potential participants accessed, and determined the feasibility of electronic information provision. A systematic review found limited empirical evidence to suggest what information potential participants want when making a participation decision. An Information Provision study was designed and embedded in an existing piece of low risk interventional research. This had three components; a feasibility study of electronic communication; a RCT of an Interactive Information Sheet (IIS); an observational study that recorded information accessed by potential participants. Results suggest electronic communication did not affect consent rate (although study was not powered to detect this) and understanding and satisfaction were unaffected by level or mode of information provision. Traditional participation information sheets (PIS) may only satisfy 11.4% participants, undersupply 9.1% and oversupply 79.5%. Participants were often unable to accurately recall what information they had accessed. In conclusion, the majority of potential participants to this study would have been satisfied with a streamlined PIS. An IIS could provide additional tailored information to those who require it, with standardised verbal information provision at consent interviews ensuring consent is given in accordance with GCP guidelines.

Feedback which induces an external focus of attention, about movement effects, has been found to promote motor performance in healthy subjects. It is unknown whether this effect transfers to retraining reach-to-grasp after stroke. This thesis first explored the attentional focus of feedback used by therapists and adopted a mixed methods paradigm. Where feedback was used it predominantly induced an internal focus of attention, about body movements. The main experimental study compared feedback which induced either an internal or external focus of attention during the motor performance of reach to grasp after stroke. A counterbalanced design was used and reaching movements were recorded using motion analysis. Support was found for adopting an external focus of attention compared with an internal focus of attention, although an interaction between feedback type and order was also found. Finally, the influence of the level of arm and memory impairment on the feedback type was explored. Neither the level of arm or memory impairment was found to influence feedback type. This study highlights the complexities of providing feedback after stroke and suggests that adopting an external focus of attention may be beneficial to improving motor performance after stroke.

Simulated patients (SPs), are widely used in communication skills teaching and testing worldwide. However, little research has been undertaken regarding the linguistic structure of the simulated consultation between students and SPs. Mixed method analysis (Conversation Analysis, Discourse Analysis and statistical analysis)of 100 transcribed assessed conversations between SPs and students were analysed for linguistic markers of conversational control, namely: talking more, interrupting more, asking questions, controlling the topic development, opening and closing the conversation. Results showed that the SP rather than the student seems to have conversational control over the conversation, except in the opening of the consultation. Qualitative analysis shows that this dominance is functional, as students have little knowledge and experience. The SP directs the conversation in order to give the student opportunities to show their skills. The SP and student seem not only to follow the rules of the ‘language game of medicine’ but also the rules of the ‘language game of education’, which suggests that the language of simulated consultations should be seen as a different genre, rather than a mirror of reality. These findings raise questions about role-play in medical education, devising scenarios, communication skills assessments, and the training of SPs.