54 research outputs found
A20 regulates lymphocyte adhesion in murine neuroinflammation by restricting endothelial ICOSL expression in the CNS.
A20 is a ubiquitin-modifying protein that negatively regulates NF-κB signaling. Mutations in A20/TNFAIP3 are associated with a variety of autoimmune diseases, including multiple sclerosis (MS). We found that deletion of A20 in central nervous system (CNS) endothelial cells (ECs) enhances experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. A20∆CNS-EC mice showed increased numbers of CNS-infiltrating immune cells during neuroinflammation and in the steady state. While the integrity of the blood-brain barrier (BBB) was not impaired, we observed a strong activation of CNS-ECs in these mice, with dramatically increased levels of the adhesion molecules ICAM-1 and VCAM-1. We discovered ICOSL as adhesion molecule expressed by A20-deficient CNS-ECs. Silencing of ICOSL in CNS microvascular ECs partly reversed the phenotype of A20∆CNS-EC mice without reaching statistical significance and delayed the onset of EAE symptoms in wildtype mice. In addition, blocking of ICOSL on primary mouse brain microvascular endothelial cells (pMBMECs) impaired the adhesion of T cells in vitro. Taken together, we here propose that CNS EC-ICOSL contributes to the firm adhesion of T cells to the BBB, promoting their entry into the CNS and eventually driving neuroinflammation
Transcriptomic epidemiology of smoking: the effect of smoking on gene expression in lymphocytes
<p>Abstract</p> <p>Background</p> <p>This investigation offers insights into system-wide pathological processes induced in response to cigarette smoke exposure by determining its influences at the gene expression level.</p> <p>Methods</p> <p>We obtained genome-wide quantitative transcriptional profiles from 1,240 individuals from the San Antonio Family Heart Study, including 297 current smokers. Using lymphocyte samples, we identified 20,413 transcripts with significantly detectable expression levels, including both known and predicted genes. Correlation between smoking and gene expression levels was determined using a regression model that allows for residual genetic effects.</p> <p>Results</p> <p>With a conservative false-discovery rate of 5% we identified 323 unique genes (342 transcripts) whose expression levels were significantly correlated with smoking behavior. These genes showed significant over-representation within a range of functional categories that correspond well with known smoking-related pathologies, including immune response, cell death, cancer, natural killer cell signaling and xenobiotic metabolism.</p> <p>Conclusions</p> <p>Our results indicate that not only individual genes but entire networks of gene interaction are influenced by cigarette smoking. This is the largest <it>in vivo </it>transcriptomic epidemiological study of smoking to date and reveals the significant and comprehensive influence of cigarette smoke, as an environmental variable, on the expression of genes. The central importance of this manuscript is to provide a summary of the relationships between gene expression and smoking in this exceptionally large cross-sectional data set.</p
Frequency and genotypic distribution of GB virus C (GBV-C) among Colombian population with Hepatitis B (HBV) or Hepatitis C (HCV) infection
<p>Abstract</p> <p>Background</p> <p>GB virus C (GBV-C) is an enveloped positive-sense ssRNA virus belonging to the <it>Flaviviridae </it>family. Studies on the genetic variability of the GBV-C reveals the existence of six genotypes: genotype 1 predominates in West Africa, genotype 2 in Europe and America, genotype 3 in Asia, genotype 4 in Southwest Asia, genotype 5 in South Africa and genotype 6 in Indonesia. The aim of this study was to determine the frequency and genotypic distribution of GBV-C in the Colombian population.</p> <p>Methods</p> <p>Two groups were analyzed: i) 408 Colombian blood donors infected with HCV (n = 250) and HBV (n = 158) from Bogotá and ii) 99 indigenous people with HBV infection from Leticia, Amazonas. A fragment of 344 bp from the 5' untranslated region (5' UTR) was amplified by nested RT PCR. Viral sequences were genotyped by phylogenetic analysis using reference sequences from each genotype obtained from GenBank (n = 160). Bayesian phylogenetic analyses were conducted using Markov chain Monte Carlo (MCMC) approach to obtain the MCC tree using BEAST v.1.5.3.</p> <p>Results</p> <p>Among blood donors, from 158 HBsAg positive samples, eight 5.06% (n = 8) were positive for GBV-C and from 250 anti-HCV positive samples, 3.2%(n = 8) were positive for GBV-C. Also, 7.7% (n = 7) GBV-C positive samples were found among indigenous people from Leticia. A phylogenetic analysis revealed the presence of the following GBV-C genotypes among blood donors: 2a (41.6%), 1 (33.3%), 3 (16.6%) and 2b (8.3%). All genotype 1 sequences were found in co-infection with HBV and 4/5 sequences genotype 2a were found in co-infection with HCV. All sequences from indigenous people from Leticia were classified as genotype 3. The presence of GBV-C infection was not correlated with the sex (p = 0.43), age (p = 0.38) or origin (p = 0.17).</p> <p>Conclusions</p> <p>It was found a high frequency of GBV-C genotype 1 and 2 in blood donors. The presence of genotype 3 in indigenous population was previously reported from Santa Marta region in Colombia and in native people from Venezuela and Bolivia. This fact may be correlated to the ancient movements of Asian people to South America a long time ago.</p
Transcriptional Enhancers in Protein-Coding Exons of Vertebrate Developmental Genes
Many conserved noncoding sequences function as transcriptional enhancers that regulate gene expression. Here, we report that protein-coding DNA also frequently contains enhancers functioning at the transcriptional level. We tested the enhancer activity of 31 protein-coding exons, which we chose based on strong sequence conservation between zebrafish and human, and occurrence in developmental genes, using a Tol2 transposable GFP reporter assay in zebrafish. For each exon we measured GFP expression in hundreds of embryos in 10 anatomies via a novel system that implements the voice-recognition capabilities of a cellular phone. We find that 24/31 (77%) exons drive GFP expression compared to a minimal promoter control, and 14/24 are anatomy-specific (expression in four anatomies or less). GFP expression driven by these coding enhancers frequently overlaps the anatomies where the host gene is expressed (60%), suggesting self-regulation. Highly conserved coding sequences and highly conserved noncoding sequences do not significantly differ in enhancer activity (coding: 24/31 vs. noncoding: 105/147) or tissue-specificity (coding: 14/24 vs. noncoding: 50/105). Furthermore, coding and noncoding enhancers display similar levels of the enhancer-related histone modification H3K4me1 (coding: 9/24 vs noncoding: 34/81). Meanwhile, coding enhancers are over three times as likely to contain an H3K4me1 mark as other exons of the host gene. Our work suggests that developmental transcriptional enhancers do not discriminate between coding and noncoding DNA and reveals widespread dual functions in protein-coding DNA
Myocyte membrane and microdomain modifications in diabetes: determinants of ischemic tolerance and cardioprotection
Congenital muscular dystrophy. Part II: a review of pathogenesis and therapeutic perspectives
Yttrium-90 radioembolization of unresectable hepatocellular carcinoma – a single center experience
Carsten Meyer,1,* Claus Christian Pieper,1,* Hojjat Ahmadzadehfar,2 Nina Alexandra Lampe,1 Eva Maria E Matuschek,1 Thomas Adrian Maschke,1 Simon Jonas Enkirch,1 Markus Essler,2 Ulrich Spengler,3 Hans Heinz Schild1 1Department of Radiology, University of Bonn, Sigmund-Freud-Strasse, Bonn, Germany, 2Department of Nuclear Medicine, University of Bonn, Sigmund-Freud-Strasse, Bonn, Germany, 3Department of Internal Medicine I, University of Bonn, Sigmund-Freud-Strasse, Bonn, Germany *These authors contributed equally to this work Purpose: To determine the value of radioembolization (RE) for treatment of unresectable hepatocellular carcinoma (HCC). Patients and methods: Records of patients undergoing RE for unresectable HCC were retrospectively reviewed. Biochemical and clinical toxicities, imaging response (according to modified Response Evaluation Criteria In Solid Tumors), time-to-progression (TTP) and overall survival (OS) were analyzed. Data were stratified according to clinical and procedural parameters. Univariate and multivariate analyses were performed. Results: One hundred and fifteen patients (89 male, mean age 69.3 years) underwent 158 REs (119 resin-, 39 glass-based) (Barcelona Clinic Liver Cancer [BCLC]-A: 6.1%, B: 33.9%, C: 60.0%). Median clinical follow-up was 5.9 (0.9–83.5) months. No grade 4 or 5 clinical toxicities were noted. Objective response rate was 35.6%; disease control rate was 76.7%. Median TTP of the treated part of the liver was 4 (0.9–45.4) months. 108/115 patients died during follow-up (median OS 8.4 [0.3–82.8] months after first RE [BCLC-A: 52.8 months, BCLC-B: 12.4 months, BCLC-C: 6.1 months]). On multivariate analysis, baseline Eastern Co-operative Oncology Group status <1, ascites prior to RE and best imaging response were predictors of longer OS. In BCLC-C patients, tumor burden, ascites prior to RE, baseline gamma-glutamyl-transferase and Child–Pugh score were predictive of OS. Conclusions: RE is safe and effective in carefully selected patients suffering from HCC with a low complication rate. Low baseline Eastern Co-operative Oncology Group status and absence of ascites prior to RE are positive prognostic factors. Keywords: radioembolization, hepatocellular carcinoma, HCC, locoregional therapy, live
On insertion of pigment-associated polypeptides during membrane biogenesis in Rhodopseudomonas capsulata
Differentiation of the membrane system in cells of Rhodopseudomonas capsulata after transition from chemotrophic to phototrophic growth conditions
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