Zebrafish Kidney Phagocytes Utilize Macropinocytosis and Ca2+-Dependent Endocytic Mechanisms

Background: The innate immune response constitutes the first line of defense against invading pathogens and consists of a variety of immune defense mechanisms including active endocytosis by macrophages and granulocytes. Endocytosis can be used as a reliable measure of selective and non-selective mechanisms of antigen uptake in the early phase of an immune response. Numerous assays have been developed to measure this response in a variety of mammalian and fish species. The small size of the zebrafish has prevented the large-scale collection of monocytes/macrophages and granulocytes for these endocytic assays. Methodology/Principal Findings: Pooled zebrafish kidney hematopoietic tissues were used as a source of phagocytic cells for flow-cytometry based endocytic assays. FITC-Dextran, Lucifer Yellow and FITC-Edwardsiella ictaluri were used to evaluate selective and non-selective mechanisms of uptake in zebrafish phagocytes. Conclusions/Significance: Zebrafish kidney phagocytes characterized as monocytes/macrophages, neutrophils and lymphocytes utilize macropinocytosis and Ca 2+-dependant endocytosis mechanisms of antigen uptake. These cells do not appear to utilize a mannose receptor. Heat-killed Edwardsiella ictaluri induces cytoskeletal interactions for internalization in zebrafish kidney monocytes/macrophages and granulocytes. The proposed method is easy to implement and should prove especially useful in immunological, toxicological and epidemiological research

Community-based provision of direct-acting antiviral therapy for hepatitis C: Study protocol and challenges of a randomized controlled trial

Background: To achieve the World Health Organization hepatitis C virus (HCV) elimination targets, it is essential to increase access to treatment. Direct-acting antiviral (DAA) treatment can be provided in primary healthcare services (PHCS), improving accessibility, and, potentially, retention in care. Here, we describe our protocol for assessing the effectiveness of providing DAAs in PHCS, and the impact on the HCV care cascade. In addition, we reflect on the challenges of conducting a model of care study during a period of unprecedented change in HCV care and treatment. Methods: Consenting patients with HCV infection attending 13 PHCS in Australia or New Zealand are randomized to receive DAA treatment at the local tertiary institution (standard care arm), or their PHCS (intervention arm). The primary endpoint is the proportion commenced on DAAs and cured. Treatment providers at the PHCS include: hepatology nurses, primary care practitioners, or, in two sites, a specialist physician. All PHCS offer opioid substitution therapy. Discussion: The Prime Study is the first real-world, randomized, model of care study exploring the impact of community provision of DAA therapy on HCV-treatment uptake and cure. Although the study has faced challenges unique to this period of time characterized by changing treatment and service delivery, the data gained will be of critical importance in shaping health service policy that enables the elimination of HCV

Declining risk of sudden death in heart failure

BACKGROUND The risk of sudden death has changed over time among patients with symptomatic heart failure and reduced ejection fraction with the sequential introduction of medi - cations including angiotensin-converting–enzyme inhibitors, angiotensin-receptor blockers, beta-blockers, and mineralocorticoid-receptor antagonists. We sought to examine this trend in detail. METHODS We analyzed data from 40,195 patients who had heart failure with reduced ejection fraction and were enrolled in any of 12 clinical trials spanning the period from 1995 through 2014. Patients who had an implantable cardioverter–defibrillator at the time of trial enrollment were excluded. Weighted multivariable regression was used to examine trends in rates of sudden death over time. Adjusted hazard ratios for sudden death in each trial group were calculated with the use of Cox regression models. The cumulative incidence rates of sudden death were assessed at different time points after randomization and according to the length of time between the diagnosis of heart failure and randomization. RESULTS Sudden death was reported in 3583 patients. Such patients were older and were more often male, with an ischemic cause of heart failure and worse cardiac function, than those in whom sudden death did not occur. There was a 44% decline in the rate of sudden death across the trials (P = 0.03). The cumulative incidence of sudden death at 90 days after randomization was 2.4% in the earliest trial and 1.0% in the most recent trial. The rate of sudden death was not higher among patients with a recent diagnosis of heart failure than among those with a longer-standing diagnosis. CONCLUSIONS Rates of sudden death declined substantially over time among ambulatory patients with heart failure with reduced ejection fraction who were enrolled in clinical trials, a finding that is consistent with a cumulative benefit of evidence-based medica - tions on this cause of death. (Funded by the China Scholarship Council and the University of Glasgow.

Management of congestive heart failure: a gender gap may still exist. Observations from a contemporary cohort

BACKGROUND: Unlike other cardiovascular diseases the incidence and prevalence of congestive heart failure (CHF) continues to increase. While gender differences in coronary artery disease have been well described, to date, there has been a relative paucity of similar data in patients with CHF. We conducted a pilot study to evaluate the profile and management of patients with CHF at a tertiary care centre to determine if a gender difference exists. METHODS: A chart review was performed at a tertiary care centre on consecutive patients admitted with a primary diagnosis of CHF between June 1997 and 1998. Co-morbidity, diagnostic investigations, and management of CHF were recorded. Comparisons between male and female patients were conducted. RESULTS: One hundred and forty five patients were reviewed. There were 80 male (M) and 65 female (F) patients of similar age [71.6 vs. 71.3 (M vs. F), p = NS]. Male patients were more likely to have had a previous myocardial infarction (66% vs. 35%, p < 0.01) and revascularization (41% vs. 20%, p < 0.05), and had worse left ventricular ejection fraction (LVEF) than women, [median LVEF 3 vs. 2 (M vs. F), p < 0.01]. Male patients were more likely to have a non-invasive assessment of left ventricular (LV) function [85% vs. 69%, (M vs. F), p < 0.05]. A logistic regression analysis suggests that amongst those without coronary disease, males were more likely to receive non-invasive testing. There were no differences in the use of prescribed medications, in this cohort. CONCLUSIONS: This pilot study demonstrated that there seem to be important gender differences in the profile and management of patients with CHF. Importantly women were less likely to have an evaluation of LV function. As assessment of LV function has significant implications on patient management, this data justifies the need for larger studies to assess gender differences in CHF profile and treatment

Effect of vitamin D on bone mineral density of elderly patients with osteoporosis responding poorly to bisphosphonates

BACKGROUND: Bisphosphonates are indicated in the prevention and treatment of osteoporosis. However, bone mineral density (BMD) continues to decline in up to 15% of bisphosphonate users. While randomized trials have evaluated the efficacy of concurrent bisphosphonates and vitamin D, the incremental benefit of vitamin D remains uncertain. METHODS: Using data from the Canadian Database of Osteoporosis and Osteopenia (CANDOO), we performed a 2-year observational cohort study. At baseline, all patients were prescribed a bisphosphonate and counseled on vitamin D supplementation. After one year, patients were divided into two groups based on their response to bisphosphonate treatment. Non-responders were prescribed vitamin D 1000 IU daily. Responders continued to receive counseling on vitamin D. RESULTS: Of 449 patients identified, 159 were non-responders to bisphosphonates. 94% of patients were women. The mean age of the entire cohort was 74.6 years (standard deviation = 5.6 years). In the cohort of non-responders, BMD at the lumbar spine increased 2.19% (p < 0.001) the year after vitamin D was prescribed compared to a decrease of 0.55% (p = 0.36) the year before. In the cohort of responders, lumbar spine BMD improved 1.45% (p = 0.014) the first year and 1.11% (p = 0.60) the second year. The difference between the two groups was statistically significant the first year (p < 0.001) but not the second (p = 0.60). Similar results were observed at the femoral neck but were not statistically significant. CONCLUSION: In elderly patients with osteoporosis not responding to bisphosphonates, vitamin D 1000 IU daily may improve BMD at the lumbar spine

Loss of Pluripotency in Human Embryonic Stem Cells Directly Correlates with an Increase in Nuclear Zinc

The pluripotency of human embryonic stem cells (hESCs) is important to investigations of early development and to cell replacement therapy, but the mechanism behind pluripotency is incompletely understood. Zinc has been shown to play a key role in differentiation of non-pluripotent cell types, but here its role in hESCs is directly examined. By mapping the distribution of metals in hESCs at high resolution by x-ray fluorescence microprobe (XFM) and by analyzing subcellular metal content, we have found evidence that loss of pluripotency is directly correlated with an increase in nuclear zinc. Zinc elevation not only redefines our understanding of the mechanisms that support pluripotency, but also may act as a biomarker and an intervention point for stem cell differentiation

Nurses' perceived barriers to the implementation of a Fall Prevention Clinical Practice Guideline in Singapore hospitals

BackgroundTheories of behavior change indicate that an analysis of barriers to change is helpful when trying to influence professional practice. The aim of this study was to assess the perceived barriers to practice change by eliciting nurses\u27 opinions with regard to barriers to, and facilitators of, implementation of a Fall Prevention clinical practice guideline in five acute care hospitals in Singapore.MethodsNurses were surveyed to identify their perceptions regarding barriers to implementation of clinical practice guidelines in their practice setting. The validated questionnaire, \u27Barriers and facilitators assessment instrument\u27, was administered to nurses (n = 1830) working in the medical, surgical, geriatric units, at five acute care hospitals in Singapore.ResultsAn 80.2% response rate was achieved. The greatest barriers to implementation of clinical practice guidelines reported included: knowledge and motivation, availability of support staff, access to facilities, health status of patients, and, education of staff and patients.ConclusionNumerous barriers to the use of the Fall Prevention Clinical Practice Guideline have been identified. This study has laid the foundation for further research into implementation of clinical practice guidelines in Singapore by identifying barriers to change in acute care settings.<br /

Development and validation of makeup and sexualized clothing questionnaires

Abstract Background Body acceptance programs on college campuses indicated that collegiate women often report feeling pressure to dress in a sexualized manner, and use makeup to enhance beauty. Currently, no quantitative measures exist to assess attitudes and daily behaviors that may arise in response to perceived pressure to wear makeup or dress in a provocative manner. The goal of the current studies was to develop brief self-report questionnaires aimed at assessing makeup and sexualized clothing use and attitudes in young women. Methods An exploratory factor analysis in a sample of 403 undergraduate women was used in Study 1 to create items to measure the pressure women feel to wear makeup and sexualized clothing. A confirmatory factor analysis (N = 153) was used in Study 2 to confirm the factor structure found in Study 1. An incremental validity analysis was also conducted in Study 2. Across both studies, participants completed online questionnaires. Results In Study 1, items were developed for two questionnaires to assess perceived pressure to wear makeup and discomfort when not wearing makeup, and perceived pressure to wear sexualized clothing, and body image concerns with regards to sexualized clothing. The exploratory factor analyses revealed Unconfident and Unease scales for the Makeup Questionnaire (MUQ) and Body Dissatisfaction and Pressure scales for the Sexualized Clothing Questionnaire (SCQ). In Study 2, the confirmatory factor analyses confirmed the factor structure for the MUQ and SCQ. The incremental validity analysis revealed that these measures can be used to predict self-objectification and shape and weight concern in women. Conclusion These studies provide preliminary support for the factor structure of two novel questionnaires aimed at assessing perceived pressure to wear makeup and sexualized clothing