Micro-scale flow cytometry-based and biochemical analysis of lipid signaling in primary B cell subpopulations

B cell subpopulations in the spleen have been extensively characterized phenotypically; however, biochemical properties of these cell populations following B cell antigen receptor engagement have not been fully determined due to technical difficulties and limiting cell numbers. We therefore employed mini-scale protocols to assess lipid signaling, particularly that of diacylglycerol and inositol trisphosphate, with as few as 0.5x106 purified early (T1) and late (T2) transitional B cells. Additionally, utilizing flow cytometric techniques, we determined levels of phosphatidylinositol bisphosphate and calcium mobilization in T1 and T2 cells, as well as mature follicular and marginal zone B cells using less than 1x106 primary B cells. Thus, these biochemical and flow cytometric methodologies can be used to analyse signal-induced changes in phosphatidylinositol bisphosphate levels, diacylglycerol and inositol triphosphate production and calcium in each B cell population

Translational Research. New Findings and Potential Future Applications in Pancreatic Adenocarcinoma

 The current achievements in pancreatic cancer diagnosis and treatment are disappointing for patients and clinicians alike. Still, in the dawn of 2012, most patients are diagnosed at a late stage where cure is not feasible, with the majority going to succumb within the same year of diagnosis. Thus, the only hope for early and diagnosis and radical treatment is the invention of diagnostic and prognostic tests which might predict accurately patients who may develop this disease and those who have the most aggressive potential, so clinician adopt the appropriate strategy. In this paper we summarize the findings from the three most interesting research abstract as presented at the 2012 American Society of Clinical Oncology Gastrointestinal Cancers Symposium. In particular, we focus on Abstract #160 which shows the diagnostic utility of microRNA serum profiling in pancreatic cancer patients, on Abstract #201 which suggests a potential prognostic role of transforming growth factor (TGF)-beta pathway in advanced pancreatic cancer, and on Abstract #165 which shows that protein S100A4 might be a new, potentially useful, predictive biomarker of gemcitabine efficacy.

Neuroendocrine Tumors of the Pancreas: What's New

Surgical excision has been the mainstay of treatment for neuroendocrine tumors of the pancreas (PNET). Compounds like streptozocin and dacarbazin have been traditionally used in inoperable cases and somatostatin to treat syndromes deriving from functional tumors. However, a lot of progress has taken place in the area of molecular characterization of these tumors, revealing activation of mammalian target of rapamycin (mTOR) and VEGF pathways. Recent data from the 2010 ASCO Gastrointestinal Cancers Symposium demonstrate antitumor activity of everolimus, an mTOR inhibitor in combination with temozolomide in a phase I/II trial and of sunitinib versus placebo in a randomized double blinded phase III trial. The role of modern biologic compounds in the treatment of PNET is not clear yet. In addition, combination of resection and transarterial chemoembolization (TACE) has been proven effective over either modality alone in the treatment of PNET metastatic to the liver in a retrospective analysis. This comes to address the problem of selecting local intervention in a metastatic disease, which has been a reasonable choice for this group of tumors in the past. Last but not least the role of Ki-67 in decision-making in PNET is being discussed.Image: Yale University School of Medicine. New Haven, CT, USA

A multi-gene signature predicts outcome in patients with pancreatic ductal adenocarcinoma.

© 2014 Haider et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Improved usage of the repertoires of pancreatic ductal adenocarcinoma (PDAC) profiles is crucially needed to guide the development of predictive and prognostic tools that could inform the selection of treatment options

Efficacy and safety of sofosbuvir based antiviral therapy for chronic hepatitis C infection in patients with advanced chronic kidney disease

Background: Screening studies for hepatitis C have proved that it is more prevalent in patients with renal diseases. Chronic hepatitis C infection in patients with kidney disease not only accelerates renal deterioration but also adversely effects morbidity and mortality. Availability of direct acting antiviral drugs has revolutionized treatment of hepatitis C even in difficult patients. In advanced kidney diseases, selection of treatment is difficult. Aim of this study was to evaluate the efficacy and safety of Sofosbuvir based DAAs in patients with advanced CKD.Methods: In this Quasi experimental study, CHC patients with or without cirrhosis having advance CKD (eGFR <30 ml/min per 1.73 m2) and/or on dialysis were enrolled. End points of the study were documentation of SVR 12 or discontinuation of therapy. Different regimens of oral DAAs with or without Ribavirin were used.Results: 86 patients with a median age of 53 years were enrolled. 37 patients were on maintenance dialysis and 49 were not on dialysis with eGFR <30 ml/min per 1.73 m2. Virological response was 92.68% at the end of treatment and SVR was achieved by 90.2% twelve weeks after therapy. Insomnia 14%, headache 11% and anemia 7% were main dverse effects. Mean eGFR and creatinine before and after treatment remained the same. Only 2 patients relapsed, both were on dialysis thrice weekly.Conclusions: All Sofosbuvir based regimens used for the treatment of CHC in patients with end stage renal disease are effective and well tolerated. Close follow up is advised to monitor side effects

Augmented B Lymphocyte Response to Antigen in the Absence of Antigen-Induced B Lymphocyte Signaling in an IgG-Transgenic Mouse Line

IgG-containing B cell antigen receptor (IgG-BCR), the BCR mostly expressed on memory B cells, contains a distinct signaling function from IgM-BCR or IgD-BCR expressed on naïve B cells. Because naïve B cells transgenic for IgG exhibit augmented response to antigens similar to memory B cells, the distinct signaling function of IgG-BCR appears to play a role in augmented antibody responses of memory B cells. However, how IgG-BCR signaling augments B cell responses is not yet well understood. Here we demonstrate that B cells from IgG-transgenic mice are anergic with defect in generation of BCR signaling upon BCR ligation. However, these IgG-transgenic B cells generate markedly augmented antibody response to a T cell-dependent antigen, probably due to hyper-responsiveness to a T cell-derived signal through CD40. Both BCR signaling defect and augmented response to CD40 ligation are partially restored in xid IgG-transgenic mice in which BCR signaling is down-modulated due to a loss-of-function mutation in the tyrosine kinase Btk crucial for BCR signaling. Thus, IgG-BCR induces augmented B cell responses in the absence of antigen-induced BCR signaling probably through high ligand-independent BCR signaling that may “idle” B cells to make them ready to respond to T cell help. This finding strongly suggests a crucial role of ligand-independent signaling in receptor function

Quantifying primaquine effectiveness and improving adherence: a round table discussion of the APMEN Vivax Working Group.

The goal to eliminate malaria from the Asia-Pacific by 2030 will require the safe and widespread delivery of effective radical cure of malaria. In October 2017, the Asia Pacific Malaria Elimination Network Vivax Working Group met to discuss the impediments to primaquine (PQ) radical cure, how these can be overcome and the methodological difficulties in assessing clinical effectiveness of radical cure. The salient discussions of this meeting which involved 110 representatives from 18 partner countries and 21 institutional partner organizations are reported. Context specific strategies to improve adherence are needed to increase understanding and awareness of PQ within affected communities; these must include education and health promotion programs. Lessons learned from other disease programs highlight that a package of approaches has the greatest potential to change patient and prescriber habits, however optimizing the components of this approach and quantifying their effectiveness is challenging. In a trial setting, the reactivity of participants results in patients altering their behaviour and creates inherent bias. Although bias can be reduced by integrating data collection into the routine health care and surveillance systems, this comes at a cost of decreasing the detection of clinical outcomes. Measuring adherence and the factors that relate to it, also requires an in-depth understanding of the context and the underlying sociocultural logic that supports it. Reaching the elimination goal will require innovative approaches to improve radical cure for vivax malaria, as well as the methods to evaluate its effectiveness

Heterogeneity in prevalence of subclinical Plasmodium falciparum and Plasmodium vivax infections but no parasite genomic clustering in the Chittagong Hill Tracts, Bangladesh

Background Malaria remains endemic in Bangladesh, with the majority of cases occurring in forested, mountainous region in the Chittagong Hill Tracts (CHT). This area is home to Bengali and diverse groups of indigenous people (Pahari) residing largely in mono-ethnic villages. Methods 1002 individuals of the 9 most prominent Pahari and the Bengali population were randomly selected and screened by RDT and qPCR. Parasites were genotyped by msp2 and deep sequencing of 5 amplicons (ama1-D3, cpmp, cpp, csp, and msp7) for Plasmodium falciparum (n = 20), and by microsatellite (MS) typing of ten loci and amplicon sequencing of msp1 for Plasmodium vivax (n = 21). Population structure was analysed using STRUCTURE software. Identity-by-state (IBS) was calculated as a measure of parasite relatedness and used to generate relatedness networks. Results The prevalence of P. falciparum and P. vivax infection was 0.7% by RDT (P. falciparum 6/1002; P. vivax 0/1002, mixed: 1/1002) and 4% by qPCR (P. falciparum 21/1002; P. vivax 16/1002, mixed: 5/1002). Infections were highly clustered, with 64% (27/42) of infections occurring in only two Pahari groups, the Khumi and Mro. Diversity was high; expected heterozygosity was 0.93 for P. falciparum and 0.81 for P. vivax. 85.7% (18/21) of P. vivax and 25% (5/20) of P. falciparum infections were polyclonal. No population structure was evident for either species, suggesting high transmission and gene flow among Pahari groups. Conclusions High subclinical infection prevalence and genetic diversity mirror ongoing transmission. Control activities should be specifically directed to Pahari groups at greatest risk