Ankyrin is the major oxidised protein in erythrocyte membranes from end-stage renal disease patients on chronic haemodialysis and oxidation is decreased by dialysis and vitamin C supplementation

Chronically haemodialysed end-stage renal disease patients are at high risk of morbidity arising from complications of dialysis, the underlying pathology that has led to renal disease and the complex pathology of chronic kidney disease. Anaemia is commonplace and its origins are multifactorial, involving reduced renal erythropoietin production, accumulation of uremic toxins and an increase in erythrocyte fragility. Oxidative damage is a common risk factor in renal disease and its co-morbidities and is known to cause erythrocyte fragility. Therefore, we have investigated the hypothesis that specific erythrocyte membrane proteins are more oxidised in end-stage renal disease patients and that vitamin C supplementation can ameliorate membrane protein oxidation. Eleven patients and 15 control subjects were recruited to the study. Patients were supplemented with 2 × 500 mg vitamin C per day for 4 weeks. Erythrocyte membrane proteins were prepared pre- and post-vitamin C supplementation for determination of protein oxidation. Total protein carbonyls were reduced by vitamin C supplementation but not by dialysis when investigated by enzyme linked immunosorbent assay. Using a western blot to detect oxidised proteins, one protein band, later identified as containing ankyrin, was found to be oxidised in patients but not controls and was reduced significantly by 60% in all patients after dialysis and by 20% after vitamin C treatment pre-dialysis. Ankyrin oxidation analysis may be useful in a stratified medicines approach as a possible marker to identify requirements for intervention in dialysis patients.

Gram-positive infections in patients with end-stage renal disease

Gram-positive microorganisms, specifically coagulase-negative staphylococci are the most common species recovered from clinical culture specimens of patients with end-stage renal disease. The propensity of coagulase-negative staphylococci (CNS) to cause infection in this patient group has been widely debated. However, it is still unclear how this usually avirulent commensal microorganism produces infection that contributes to high rates of morbidity and mortality in patients with end-stage renal disease. The aim of this thesis was to investigate the rate, geographical distribution, molecular and phenotypic mechanisms of Gram-positive microorganisms associated with infection in renal dialysis patients. In addition, it sought to assess the value of early serological diagnosis of dialysis catheter-associated infection and the effect of antimicrobial treatment regimens on the faecal carriage of enteric microorganisms. In this study, the incidence of haemodialysis catheter-associated infection was established with the Meditrend audit tool. This tool was used to assess the infection outcomes of catheter insertion and management procedures until the catheter was explanted. Introduction of a catheter management protocol decreased the incidence of catheter-related infection. Staphylococcal species recovered from episodes of haemodialysis catheter-associated infection and continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis were genotyped by determination of macrorestriction profiles with pulsed-field gel electrophoresis. This highlighted horizontal transfer of microorganisms between different patients and the environment. The phenotypic characteristics of these strains were also investigated to determine characteristics that could be used as markers for dialysis catheter-associated infection. The expression of elastase, lipase and esterase by CNS was significantly associated with infection. A rapid enzyme-linked immunosorbent assay incorporating a novel staphylococcal antigen (lipid S) was used to evaluate the early detection of anti-staphylococcal immunoglobulin gamma in patient sera. The comparison of culture positive and culture negative patients demonstrated a steady state of immune activation in both groups. However anti-lipid S serum antibody titres > 1000 were found to be a predictor of infection. The effect on faecal carriage of vancomycin resistant enterococci (VRE) and Clostridium difficile toxins in patients treated with CAPD when empiric cephalosporin therapy was substituted for piperacillin/tazobactam was investigated. The introduction of piperacillin/tazobactam demonstrated a decrease in the faecal carriage of VRE.

Genotypic and phenotypic properties of coagulase-negative staphylococci causing dialysis catheter-related sepsis

Sixty coagulase-negative staphylococcus (CNS) isolates were recovered from the blood cultures or peritoneal dialysate effluent of 43 patients on renal dialysis. The patients had either renal dialysis catheter-related sepsis (CRS) or continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis. Isolates were characterized by biotyping, and genotyped by pulsed-field gel electrophoresis (PFGE). Phenotypic properties of the strains were also investigated. Several genotypes were identified with no one specific strain of CNS being associated with CRS. However, closely related strains were isolated from several patients within the units studied, suggesting horizontal transfer of micro-organisms. Genotypic macro-restriction profiles did not concur with phenotypic profiles or biotypes, confirming that genotyping is required for epidemiological studies. All staphylococcal strains were investigated for the production of phenotypic characteristics. Significant differences were predominantly seen in the production of lipase, esterase and elastase in strains isolated from the renal patients with CRS and CAPD-associated peritonitis, compared with a non-septic control group. These phenotypic characteristics may therefore have a role in the maintenance of CRS in renal patients. © 2003 The Hospital Infection Society. Published by Elsevier Science Ltd. All rights reserved.

Type 2 diabetes and dog walking:patients' longitudinal perspectives about implementing and sustaining physical activity

Background - Physical activity is particularly important for people with type 2 diabetes, as evidence suggests that any reduction in sedentary time is good for metabolic health. Aim - To explore type 2 diabetes patients' talk about implementing and sustaining physical activity. Design of study - Longitudinal, qualitative study using repeat in-depth interviews with 20 patients over 4 years following clinical diagnosis. Setting - Patients were recruited from 16 general practices and three hospitals across Lothian, Scotland. Results - Discussion, and salience, of physical activity was marginal in patient accounts of their diabetes management. Patients claimed to have only received vague and non-specific guidance about physical activity from health professionals, and emphasised a perceived lack of interest and encouragement. Aside from walking, physical activities which were adopted tended to attenuate over time. Patients' accounts revealed how walking a dog assisted this kind of activity maintenance over time. Three main themes are highlighted in the analysis: 1) incidental walking; 2) incremental physical activity gains; and 3) augmenting physical activity maintenance. The problems arising from walking without a dog (for example, lack of motivation) are also examined. Conclusion - Asking patients about pet preferences might seem tangential to medical interactions. However, encouraging dog walking or identifying another interest that promotes a regular commitment to undertake physical activity may yield long-term health benefits.

Educational intervention improves anticoagulation control in atrial fibrillation patients:the TREAT randomised trial

Background: Stroke prevention in atrial fibrillation (AF), most commonly with warfarin, requires maintenance of a narrow therapeutic target (INR 2.0 to 3.0) and is often poorly controlled in practice. Poor patient-understanding surrounding AF and its’ treatment may contribute to patient’s willingness to adhere to recommendations. Method: A theory-driven intervention, developed using patient interviews and focus groups, consisting of a one-off group session (1-6 patients) utilising an ‘expert-patient’ focussed DVD, educational booklet, self-monitoring diary and worksheet, was compared in a randomised controlled trial (ISRCTN93952605) against usual care, with patient postal follow-ups at 1, 2, 6, and 12-months. Ninety-seven warfarin-naïve AF patients were randomised to intervention (n=46, mean age (SD) 72.0 (8.2), 67.4% men), or usual care (n=51, mean age (SD) 73.7 (8.1), 62.7% men), stratified by age, sex, and recruitment centre. Primary endpoint was time within therapeutic range (TTR); secondary endpoints included knowledge, quality of life, anxiety/depression, beliefs about medication, and illness perceptions. Main findings: Intervention patients had significantly higher TTR than usual care at 6-months (76.2% vs. 71.3%; p=0.035); at 12-months these differences were not significant (76.0% vs. 70.0%; p=0.44). Knowledge increased significantly across time (F (3, 47) = 6.4; p<0.01), but there were no differences between groups (F (1, 47) = 3.3; p = 0.07). At 6-months, knowledge scores predicted TTR (r=0.245; p=0.04). Patients’ scores on subscales representing their perception of the general harm and overuse of medication, as well as the perceived necessity of their AF specific medications predicted TTR at 6- and 12-months. Conclusions: A theory-driven educational intervention significantly improves TTR in AF patients initiating warfarin during the first 6-months. Adverse clinical outcomes may potentially be reduced by improving patients’ understanding of the necessity of warfarin and reducing their perception of treatment harm. Improving education provision for AF patients is essential to ensure efficacious and safe treatment.

The role of interpersonal functioning in the maintenance of eating psychopathology:a systematic review and testable model

This review aims to systematically evaluate the empirical literature relating to the interpersonal functioning of those with eating disorder psychopathology and presents a preliminary model to help the formulation of patients' problems. Following a thorough literature search, 35 papers were included in this systematic review. The vast majority of studies indicate a strong association between eating psychopathology and certain maladaptive personality traits. The origins of social anxiety and poor social support that have been described as maintaining eating disorders appear to differ according to diagnostic groups. Interpersonal difficulties in people with restrictive behaviors such as anorexia appear to be related to the avoidance of expressing feelings to others and to giving priority to other people's feeling over their own. While interpersonal difficulties in patients with bulimia nervosa appear to be more related to interpersonal distrust and negative interaction and conflict with others. These concepts are presented in a preliminary model of interpersonal functioning in the eating disorders. © 2012 Elsevier Ltd.

Alogliptin after acute coronary syndrome in patients with type 2 diabetes

Background - To assess potentially elevated cardiovascular risk related to new antihyperglycemic drugs in patients with type 2 diabetes, regulatory agencies require a comprehensive evaluation of the cardiovascular safety profile of new antidiabetic therapies. We assessed cardiovascular outcomes with alogliptin, a new inhibitor of dipeptidyl peptidase 4 (DPP-4), as compared with placebo in patients with type 2 diabetes who had had a recent acute coronary syndrome. Methods - We randomly assigned patients with type 2 diabetes and either an acute myocardial infarction or unstable angina requiring hospitalization within the previous 15 to 90 days to receive alogliptin or placebo in addition to existing antihyperglycemic and cardiovascular drug therapy. The study design was a double-blind, noninferiority trial with a prespecified noninferiority margin of 1.3 for the hazard ratio for the primary end point of a composite of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. Results - A total of 5380 patients underwent randomization and were followed for up to 40 months (median, 18 months). A primary end-point event occurred in 305 patients assigned to alogliptin (11.3%) and in 316 patients assigned to placebo (11.8%) (hazard ratio, 0.96; upper boundary of the one-sided repeated confidence interval, 1.16; P<0.001 for noninferiority). Glycated hemoglobin levels were significantly lower with alogliptin than with placebo (mean difference, -0.36 percentage points; P<0.001). Incidences of hypoglycemia, cancer, pancreatitis, and initiation of dialysis were similar with alogliptin and placebo. Conclusions - Among patients with type 2 diabetes who had had a recent acute coronary syndrome, the rates of major adverse cardiovascular events were not increased with the DPP-4 inhibitor alogliptin as compared with placebo. (Funded by Takeda Development Center Americas; EXAMINE ClinicalTrials.gov number, NCT00968708.)

Population pharmacokinetic and pharmacogenetic analysis of 6-mercaptopurine in paediatric patients with acute lymphoblastic leukaemia

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • The cytotoxic effects of 6-mercaptopurine (6-MP) were found to be due to drug-derived intracellular metabolites (mainly 6-thioguanine nucleotides and to some extent 6-methylmercaptopurine nucleotides) rather than the drug itself. • Current empirical dosing methods for oral 6-MP result in highly variable drug and metabolite concentrations and hence variability in treatment outcome. WHAT THIS STUDY ADDS • The first population pharmacokinetic model has been developed for 6-MP active metabolites in paediatric patients with acute lymphoblastic leukaemia and the potential demographic and genetically controlled factors that could lead to interpatient pharmacokinetic variability among this population have been assessed. • The model shows a large reduction in interindividual variability of pharmacokinetic parameters when body surface area and thiopurine methyltransferase polymorphism are incorporated into the model as covariates. • The developed model offers a more rational dosing approach for 6-MP than the traditional empirical method (based on body surface area) through combining it with pharmacogenetically guided dosing based on thiopurine methyltransferase genotype. AIMS - To investigate the population pharmacokinetics of 6-mercaptopurine (6-MP) active metabolites in paediatric patients with acute lymphoblastic leukaemia (ALL) and examine the effects of various genetic polymorphisms on the disposition of these metabolites. METHODS - Data were collected prospectively from 19 paediatric patients with ALL (n = 75 samples, 150 concentrations) who received 6-MP maintenance chemotherapy (titrated to a target dose of 75 mg m−2 day−1). All patients were genotyped for polymorphisms in three enzymes involved in 6-MP metabolism. Population pharmacokinetic analysis was performed with the nonlinear mixed effects modelling program (nonmem) to determine the population mean parameter estimate of clearance for the active metabolites. RESULTS - The developed model revealed considerable interindividual variability (IIV) in the clearance of 6-MP active metabolites [6-thioguanine nucleotides (6-TGNs) and 6-methylmercaptopurine nucleotides (6-mMPNs)]. Body surface area explained a significant part of 6-TGNs clearance IIV when incorporated in the model (IIV reduced from 69.9 to 29.3%). The most influential covariate examined, however, was thiopurine methyltransferase (TPMT) genotype, which resulted in the greatest reduction in the model's objective function (P < 0.005) when incorporated as a covariate affecting the fractional metabolic transformation of 6-MP into 6-TGNs. The other genetic covariates tested were not statistically significant and therefore were not included in the final model. CONCLUSIONS - The developed pharmacokinetic model (if successful at external validation) would offer a more rational dosing approach for 6-MP than the traditional empirical method since it combines the current practice of using body surface area in 6-MP dosing with a pharmacogenetically guided dosing based on TPMT genotype.

Set-up and maintenance of syringe drivers for subcutaneous drug administration in palliative care

Focal points: Details of syringe driver use were collected from 11 inpatient hospice units in the West Midlands and compared with predetermined standards set by a multidisciplinary group We recorded 294 syringe driver events which complied with standards for the choice of administration site, protection of the syringe driver from light and the reason for initiation of the infusion Issues of nurse training, variability in prescribing practices, provision of written information for patients, labelling and documentation of the diluent used were all identified as areas in which compliance with standards could be improved

Community pharmacist perceptions of the loss of resale price maintenance

Focal points: This study was designed to elicit the views of community pharmacists on any perceived business and professional changes following the loss of resale price maintenance (RPM)A piloted, 22-point self-completion questionnaire containing open, closed and scaled response questions was distributed to 35 independent (<10 stores), 13 multiple group and three supermarket-based pharmacies, and 40 responses were obtained (29 independent, eight multiple and three supermarket)Theme analysis indicated that 20 respondents felt that an increased range of services was now provided, 27 reported a decreased sales potential and 25 thought that patients now purchased more medicinesThe average price at which eight common over-the-counter medicines were offered was found to be £4.34 in independents, £4.37 in multiples and £4.22 in the supermarket pharmacies, compared with an average standard list price of £4.32There are indications that removal of RPM may have instigated changes in community pharmacy

Self-monitoring of blood glucose in Black Caribbean and South Asian Canadians with non-insulin treated Type 2 diabetes mellitus:a qualitative study of patients' perspectives

Background: To examine the views and current practice of SMBG among Black Caribbean and South Asian individuals with non-insulin treated Type 2 diabetes mellitus. Methods: Twelve participants completed semi-structured interviews that were guided by the Health Belief Model and analyzed using thematic network analysis. Results: The frequency of monitoring among participants varied from several times a day to once per week. Most participants expressed similar experiences regarding their views and practices of SMBG. Minor differences across gender and culture were observed. All participants understood the benefits, but not all viewed SMBG as beneficial to their personal diabetes management. SMBG can facilitate a better understanding and maintenance of self-care behaviours. However, it can trigger both positive and negative emotional responses, such as a sense of disappointment when high readings are not anticipated, resulting in emotional distress. Health care professionals play a key role in the way SMBG is perceived and used by patients. Conclusion: While the majority of participants value SMBG as a self-management tool, barriers exist that impede its practice, particularly its cost. How individuals cope with these barriers is integral to understanding why some patients adopt SMBG more than others. © 2013 Gucciardi et al.; licensee BioMed Central Ltd.