971 resultados para B Virus-infections


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Introduction Chronic hepatitis B virus (HBV) infection and liver steatosis (LS) are the most common causes of chronic liver disease, and their coexistence is frequently observed in clinical practice. Although metabolic syndrome is the main cause of LS, it has not been associated with HBV infection. The aims of this study were to describe the lipid profile and prevalence of LS among HBV carriers and to identify the characteristics associated with LS in this group. Methods This retrospective cross-sectional study included hepatitis B surface antigen (HBsAg)-positive patients evaluated during 2011 and 2012. Results Of the 83 patients included, the mean age was 46.4±12.5 years, 53% were men, and 9.1% were hepatitis B e antigen (HBeAg) -positive. These patients exhibited the following lipid profile: total cholesterol = 175.4±38.8mg/dL, low-density lipoprotein (LDL) = 113.0±32.7mg/dL, and triglycerides = 91.1±45.2mg/dL. Their fasting glucose was 95.3±14.5g/dL, and fasting insulin was 6.1±5.9µIU/mL. Liver steatosis was observed on abdominal ultrasound in 11.3% of individuals. Factors associated with the presence of LS included higher levels of total cholesterol, prothrombin activity, fasting insulin, and body mass index (BMI) as well as lower levels of aspartate aminotransferase (AST). Conclusions These findings suggest that LS in patients with chronic HBV appears to be a consequence of metabolic alterations and insulin action rather than of viral factors.

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Laboratory surveillance of influenza has shown a low virus activity in Rio de Janeiro during 1980 and 1981. A few influenza A (H3N2) viruses were isolated in both years during the winter months. Serological investigations showed that this subtype has circulated mostly among children under 10 years of age. No H1N1 virus was isolated but an increase in the proportion of adults with antibody to his virus was noted in sera collected in 1981. Influenza B virus was isolated from children in the spring of 1981 and again an increase was noted in the proportion of adults with antibody to this virus.

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Little is known on a putative effect of vitamin D on CD8+ T cells. Yet, these cells are involved in the immmunopathogenesis of MS. We assessed the cytokine profile of EBV-specific CD8+ T cells of 10 early MS patients and 10 healthy control subjects with or without 1,25(OH)(2)D(3) and found that, with 1,25(OH)(2)D(3), these cells secreted less IFN-γ and TNF-α and more IL-5 and TGF-β. CD4+ T cell depletion or even culture with CD8+ T cells only did not abolish the immunomodulatory effect of 1,25(OH)(2)D(3) on CD8+ T cells, suggesting that 1,25(OH)(2)D(3) can act directly on CD8+ T cells.

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Lentiviral vectors infect quiescent cells and allow for the delivery of genes to discrete brain regions. The present study assessed whether stable lentiviral gene transduction can be achieved in the monkey nigrostriatal system. Three young adult Rhesus monkeys received injections of a lentiviral vector encoding for the marker gene beta galatosidase (beta Gal). On one side of the brain, each monkey received multiple lentivirus injections into the caudate and putamen. On the opposite side, each animal received a single injection aimed at the substantia nigra. The first two monkeys were sacrificed 1 month postinjection, while the third monkey was sacrificed 3 months postinjection. Robust incorporation of the beta Gal gene was seen in the striatum of all three monkeys. Stereological counts revealed that 930,218; 1,192,359; and 1,501,217 cells in the striatum were beta Gal positive in monkeys 1 (n = 2) and 3 (n = 1) months later, respectively. Only the third monkey had an injection placed directly into the substantia nigra and 187,308 beta Gal-positive cells were identified in this animal. The injections induced only minor perivascular cuffing and there was no apparent inflammatory response resulting from the lentivirus injections. Double label experiments revealed that between 80 and 87% of the beta Gal-positive cells were neurons. These data indicate that robust transduction of striatal and nigral cells can occur in the nonhuman primate brain for up to 3 months. Studies are now ongoing testing the ability of lentivirus encoding for dopaminergic trophic factors to augment the nigrostriatal system in nonhuman primate models of Parkinson's disease.

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A seroprevalence study was carried out among a group of women in Rio de Janeiro to determine the prevalence of different markers for viral hepatitis given the limited data among healthy populations. Blood samples collected and tested from 874 women before or after delivery in a public county maternity hospital demonstrated age to be directly related to markers for hepatitis A virus and hepatitis B virus (HBV) infection. The prevalence of HBV and hepatitis C virus infection were lower than that observed in the blood donor population and might be explained by the younger age group and gender.

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Hepatitis D virus (HDV) is a subviral agent which depends on the envelope proteins (HBsAg) of hepatitis B virus (HBV). Therefore, hepatitis D is observed only in patients infected with HBV. Chronic hepatitis D is the least frequent albeit most severe form of chronic viral hepatitis. A resurgence of chronic hepatitis D has been observed in Northern and Central Europe, mainly due to immigration of patients from regions with high prevalence. Every HBsAg-positive patient should be screened for concurrent HDV infection. Standard treatment consists of pegylated interferon-alpha for at least one year. Sustained virological response rates are approximately 20%. Liver transplantation should be considered in patients with advanced cirrhosis or limited hepatocellular carcinoma. Preventive measures for hepatitis D are the same as for hepatitis B.

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Background and aim: H epatitis E v irus (HEV) infection has emerged as a c ause o f travel-related a nd autochthonous a cute hepatitis as well as chronic hepatitis in immunosuppressed patients. While t ravel-related cases a re c aused primarily b y infections w ith HEV of g enotype 1 ( HEV-1), autochthonous c ases a nd chronic cases a re d ue t o genotype 3 (HEV-3), which is s hared between humans and diverse animal species. The aim of this study was to establish HEV RNA detection assays f or q uantitative v iral load testing and genotyping. Methods: V iral RNA was p urified from plasma or s erum a nd converted to cDNA prior to (1) multiplex real-time PCR for HEV RNA quantification and (2) multiplex PCR coupled to DNA sequencing for HEV genotype determination. Real-time PCR was d esigned to match a ll known HEV genotypes available i n Genbank while PCR was designed using conserved primers flanking a variable region of the HEV RNA. Results: In a validation panel, the newly developed assays allowed for the reliable detection and genotyping of HEV-1 or HEV-3. Cases of t ravel-related and a utochthonous a cute h epatitis E a s well a s chronic hepatitis E i n immunosuppressed patients have b een identified using t hese a ssays a nd will be p resented in detail. Anti- HEV antibodies were n egative i n three well-characterized patients with chronic hepatitis E after organ transplantation. Conclusions: We developed and validated a quantitative HEV RNA detection assay that c an now be o ffered on a r outine basis (www.chuv.ch/imul/imu-collaborations-viral_hepatitis). Genotyping can also be offered on selected cases. HEV RNA detection is key in diagnosing chronic hepatitis E i n immunosuppressed patients with unexplained transaminase elevations, as serology can be negative in these patients.

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Protection from reactivation of persistent herpes virus infection is mediated by Ag-specific CD8 T cell responses, which are highly regulated by still poorly understood mechanisms. In this study, we analyzed differentiation and clonotypic dynamics of EBV- and CMV-specific T cells from healthy adults. Although these T lymphocytes included all subsets, from early-differentiated (EM/CD28(pos)) to late-differentiated (EMRA/CD28(neg)) stages, they varied in the sizes/proportions of these subsets. In-depth clonal composition analyses revealed TCR repertoires, which were highly restricted for CMV- and relatively diverse for EBV-specific cells. Virtually all virus-specific clonotypes identified in the EMRA/CD28(neg) subset were also found within the pool of less differentiated "memory" cells. However, striking differences in the patterns of dominance were observed among these subsets, because some clonotypes were selected with differentiation while others were not. Late-differentiated CMV-specific clonotypes were mostly characterized by TCR with lower dependency on CD8 coreceptor interaction. Yet all clonotypes displayed similar functional avidities, suggesting a compensatory role of CD8 in the clonotypes of lower TCR avidity. Importantly, clonotype selection and composition of each virus-specific subset upon differentiation was highly preserved over time, with the presence of the same dominant clonotypes at specific differentiation stages within a period of 4 years. Remarkably, clonotypic distribution was stable not only in late-differentiated but also in less-differentiated T cell subsets. Thus, T cell clonotypes segregate with differentiation, but the clonal composition once established is kept constant for at least several years. These findings reveal novel features of the highly sophisticated control of steady state protective T cell activity in healthy adults.

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Aims: To evaluate whether ki-67 labelling index (LI) has independent prognostic value for survival of patients with bladder urothelial tumours graded according to the 2004 World Health Organisation classification. Methods: Ki-67 LI was evaluated in 164 cases using the grid counting method. Non-invasive (stage Ta) tumours were: papilloma (n = 5), papillary urothelial neoplasia of low malignant potential (PUNLMP; n = 26), and low (LG; n = 34) or high grade (HG; n = 15) papillary urothelial carcinoma. Early invasive (stage T1) tumours were: LG (n = 58) and HG (n = 26) carcinoma. Statistical analysis included Fisher and x2 tests, and mean comparisons by ANOVA and t test. Univariate and multivariate survival analyses were performed according to the Kaplan–Meier method with log rank test and Cox’s proportional hazard method. Results: Mean ki-67 LI increased from papilloma to PUNLMP, LG, and HG in stage Ta (p,0.0001) and from LG to HG in stage T1 (p = 0.013) tumours. High tumour proliferation (.13%) was related to greater tumour size (p = 0.036), recurrence (p = 0.036), progression (p = 0.035), survival (p = 0.054), and high p53 accumulation (p = 0.015). Ki-67 LI and tumour size were independent predictors of disease free survival (DFS), but only ki-67 LI was related to progression free survival (PFS). Cancer specific overall survival (OS) was related to ki-67 LI, tumour size, and p27kip1 downregulation. Ki-67 LI was the main independent predictor of DFS (p = 0.0005), PFS (p = 0.0162), and cancer specific OS (p = 00195). Conclusion: Tumour proliferation measured by Ki-67 LI is related to tumour recurrence, stage progression, and is an independent predictor of DFS, PFS, and cancer specific OS in TaT1 bladder urothelial cell carcinoma.

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Few studies are available on hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection in populations living in small and medium-sized Brazilian cities. We evaluated the seroprevalence of these viruses in selected individuals from a clinic of infectology, who were referred to the University Regional Hospital of the West Region of state of São Paulo, Brazil. Among a total of 7,021 individuals seen in the clinic following receipt of preliminary ELISA results or having the suggested clinical signs of viral hepatitis or HIV, 1,228 were systematically screened. Isolated or associated HBsAg, HCV and HIV antibodies were found in 44.9% of the subjects. Anti-HIV antibodies were found in 24.7% of the patients, 20.3% of whom had an HIV monoinfection and 4.4% of whom were co-infected with hepatitis viruses (HCV: 4%; HBV: 0.4%). Anti-HCV antibodies were found in 14% of the patients and 5.9% had anti-HBsAg antibodies. HCV infection affected males more than females (p < 0.05) and individuals > 50-years old had an increased prevalence of anti-HCV compared to HIV (p = 0.0001) or HBV (p = 0.0063). HCV-RNA was detected in 73.5% of the samples with a predominance of genotype 1 (72.5%). A significant percentage (44.9%) of the selected individuals was positive for antibodies against HBV, HCV and/or HIV; these patients would otherwise have remained undiagnosed.

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Influenza surveillance networks must detect early the viruses that will cause the forthcoming annual epidemics and isolate the strains for further characterization. We obtained the highest sensitivity (95.4%) with a diagnostic tool that combined a shell-vial assay and reverse transcription-PCR on cell culture supernatants at 48 h, and indeed, recovered the strain

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The aim of this study was to determine the prevalence and the incidence of hepatitis B virus (HBV) among haemodialysis (HD) subjects and to evaluate whether testing for serological markers at the time of admission is suitable for HBV screening in this population. One hundred twenty-three patients belonging to two HD centres from São Paulo, Brazil, were tested prospectively. HBV DNA was detected by polymerase chain reaction (PCR) in each of the prospective subjects (n = 123) during one year. Additionally, all samples (n = 1,476) were analysed for HBV serological markers. The prevalence of hepatitis B core antibody (anti-HBc), hepatitis B surface antigen (HBsAg) and HBV DNA were 34.1%, 15.4% and 8.1%, respectively, while the incidence was null. Fluctuation in HBV serology was observed in one patient. Only 37.8% (17/45) of cases responded to the HBV vaccine. Our results suggest that employing more than one HBV marker and repeated follow-up evaluations may improve HBV screening in HD units.

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BACKGROUND: In this study we compared the immunogenicity of influenza vaccine administered intradermally to the standard intramuscular vaccination in lung transplant recipients. METHODS: Patients were randomized to receive the trivalent inactivated seasonal 2008-9 influenza vaccine containing either 6 μg (intradermal) or 15 μg (intramuscular) of hemagglutinin per viral strain. Immunogenicity was assessed by measurement of geometric mean titer of antibodies using the hemagglutination-inhibition (HI) assay. Vaccine response was defined as a 4-fold or higher increase of antibody titers to at least one vaccine antigen. RESULTS: Eighty-five patients received either the intradermal (n = 41) or intramuscular (n = 44) vaccine. Vaccine response was seen in 6 of 41 patients (14.6%) in the intradermal vs 8 of 43 (18.6%) in the intramuscular group (p = 0.77). Seroprotection (HI ≥1:32) was 39% for H1N1, 83% for H3N2 and 29% for B strain in the intradermal group vs 28% for H1N1, 98% for H3N2 and 58% for B strain in the intramuscular group (p = 0.36 for H1N1, p = 0.02 for H3N2, p < 0.01 for B). Mild adverse events were seen in 44% of patients in the intradermal group and 34% in the intramuscular group (p = 0.38). CONCLUSIONS: Immunogenicity of the 2008-9 influenza vaccine given intradermally or intramuscularly was overall poor in lung transplant recipients. Novel strategies for influenza vaccination in this population are needed.

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INTRODUCTION Human host immune response following infection with the new variant of A/H1N1 pandemic influenza virus (nvH1N1) is poorly understood. We utilize here systemic cytokine and antibody levels in evaluating differences in early immune response in both mild and severe patients infected with nvH1N1. METHODS We profiled 29 cytokines and chemokines and evaluated the haemagglutination inhibition activity as quantitative and qualitative measurements of host immune responses in serum obtained during the first five days after symptoms onset, in two cohorts of nvH1N1 infected patients. Severe patients required hospitalization (n = 20), due to respiratory insufficiency (10 of them were admitted to the intensive care unit), while mild patients had exclusively flu-like symptoms (n = 15). A group of healthy donors was included as control (n = 15). Differences in levels of mediators between groups were assessed by using the non parametric U-Mann Whitney test. Association between variables was determined by calculating the Spearman correlation coefficient. Viral load was performed in serum by using real-time PCR targeting the neuraminidase gene. RESULTS Increased levels of innate-immunity mediators (IP-10, MCP-1, MIP-1beta), and the absence of anti-nvH1N1 antibodies, characterized the early response to nvH1N1 infection in both hospitalized and mild patients. High systemic levels of type-II interferon (IFN-gamma) and also of a group of mediators involved in the development of T-helper 17 (IL-8, IL-9, IL-17, IL-6) and T-helper 1 (TNF-alpha, IL-15, IL-12p70) responses were exclusively found in hospitalized patients. IL-15, IL-12p70, IL-6 constituted a hallmark of critical illness in our study. A significant inverse association was found between IL-6, IL-8 and PaO2 in critical patients. CONCLUSIONS While infection with the nvH1N1 induces a typical innate response in both mild and severe patients, severe disease with respiratory involvement is characterized by early secretion of Th17 and Th1 cytokines usually associated with cell mediated immunity but also commonly linked to the pathogenesis of autoimmune/inflammatory diseases. The exact role of Th1 and Th17 mediators in the evolution of nvH1N1 mild and severe disease merits further investigation as to the detrimental or beneficial role these cytokines play in severe illness.