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‣ Prevalence, Incidence Density, and Genotype Distribution of GB Virus C Infection in a Cohort of Recently HIV-1-Infected Subjects in Sao Paulo, Brazil

GIRET, Maria Teresa M.; MIRAGLIA, Joao Luiz; SUCUPIRA, Maria Cecilia Araripe; NISHIYA, Anna; LEVI, Jose Eduardo; DIAZ, Ricardo S.; SABINO, Ester C.; KALLAS, Esper G.
Fonte: PUBLIC LIBRARY SCIENCE Publicador: PUBLIC LIBRARY SCIENCE
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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Background: The results of previous studies elsewhere have indicated that GB virus C (GBV-C) infection is frequent in patients infected with the human immunodeficiency virus type 1 (HIV-1) due to similar transmission routes of both viruses. The aim of this study was to determine the prevalence, incidence density and genotypic characteristics of GBV-C in this population. Methodology/Principal Findings: The study population included 233 patients from a cohort primarily comprised of homosexual men recently infected with HIV-1 in Sao Paulo, Brazil. The presence of GBV-C RNA was determined in plasma samples by reverse transcriptase-nested polymerase chain reaction and quantified by real-time PCR. GBV-C genotypes were determined by direct sequencing. HIV viral load, CD4+ T lymphocyte and CD8+ T lymphocyte count were also tested in all patients. The overall prevalence of GBV-C infection was 0.23 (95% CI: 0.18 to 0.29) in the study group. There was no significant difference between patients with and without GBV-C infection and Glycoprotein E2 antibody presence regarding age, sex, HIV-1 viral load, CD4+ and CD8+ T cell counts and treatment with antiretroviral drugs. An inverse correlation was observed between GBV-C and HIV-1 loads at enrollment and after one year. Also...

‣ Prevalence and distribution of the GBV-C/HGV among HIV-1-infected patients under anti-retroviral therapy

ALCALDE, Rosana; NISHIYA, Anna; CASSEB, Jorge; INOCENCIO, Lilian; FONSECA, Luiz A. M.; DUARTE, Alberto J. S.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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Infection with GB virus C (GBV-C) or hepatitis G virus (HGV) is highly prevalent among HIV/AIDS patients. GBV-C/HGV viremia has not been associated with liver disease and seems to slow HIV disease progression. To study the GBV-C/HGV genotypes prevalence among HIV/AIDS patients and its association with HIV viral load (VL) and CD4+ lymphocyte counts. From February 2003 to February 2004, we analyzed 210 HIV-1-infected subjects who were on anti-retroviral therapy (ART). For 63 of them a PCR-nested to the non-coding 5` (5`NCR) region of the GBV-C/HGV was done, and for 49 a DNA direct sequencing was done. A phylogenetic analysis was performed by PHYLIP program. 63(30%) of the HIV-1-infected patients were co-infected with GBV-C/HGV. The phylogenetic analysis revealed the following genotypes (and respective relative frequencies): 1(10%), 2a (41%), 2b (43%), and 3 (6%). Co-infected patients presented lower HIV-1 VL and higher T CD4+ lymphocyte cells counts as compared with patients negative for GBV-C/HGV sequences (log = 4.52 vs. 4.71, p = 0.036), and T CD4+ lymphocyte counts (cells/mm(3) = 322.6 vs. 273.5, p = 0.081, respectively). T CD4+ cells counts equal to, or higher than, 200/mm(3) were significantly more common among co-infected patients than among HIV-infected-only patients (p = 0.042). The lowest T CD4+ cells counts were associated with genotype 1 and the highest with genotype 2b (p = 0.05). The GBV-C/HGV infection prevalence was 30% among HIV-1-infected subjects...

‣ GB virus type C infection modulates T-cell activation independently of HIV-1 viral load

MAIDANA-GIRET, Maria Teresa; SILVA, Tania M.; SAUER, Mariana M.; TOMIYAMA, Helena; LEVI, Jose Eduardo; BASSICHETTO, Katia C.; NISHIYA, Anna; DIAZ, Ricardo S.; SABINO, Ester C.; PALACIOS, Ricardo; KALLAS, Esper Georges
Fonte: LIPPINCOTT WILLIAMS & WILKINS Publicador: LIPPINCOTT WILLIAMS & WILKINS
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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Background: Many clinical studies have suggested a beneficial effect of GB virus type C (GBV-C) on the course of HIV-1 infection, but the mechanisms involved in such amelioration are not clear. As recent evidence has implicated cellular activation in HIV-1 pathogenesis, we investigated the effect of GBV-C viremia on T-cell activation in early HIV-1 infection. Methods: Forty-eight recently infected HIV-1 patients (23 GBV-C viremic) were evaluated for T-cell counts, expanded immunophenotyping GBV-C RNA detection, and HIV-1 viral load. Nonparametric univariate and multivariate analyses were carried out to identify variables associated with cellular activation, including GBV-C status, HIV-1 viral load, T lymphocyte counts, and CD38 and chemokine (C-C motif) receptor 5 (CCR5) surface expression. Finding: We not only confirmed the positive correlation between HIV-1 viral load and the percentage of T cells positive for CD38(+)CD8(+) but also observed that GBV-C viremic patients had a lower percentage of T cells positive for CD38(+)CD4(+), CD38(+)CD8(+), CCR5(+)CD4(+), and CCR5(+)CD8(+) compared with HIV-1-infected patients who were not GBV-C viremic. In regression models, GBV-C RNA(+) status was associated with a reduction in the CD38 on CD4(+) or CD8(+) T cells and CCR5(+) on CD8(+) T cells...

‣ Evaluation of GBV-C / HVG viremia in HIV-infected women; Avaliação da viremia por GBV-C/HGV em mulheres infectadas pelo HIV

Silva, Synara Araújo; Rodrigues, Célia Lima; Campos, Aléia Faustino; Levi, José Eduardo
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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The present study aimed at standardizing a real-time quantitative polymerase chain reaction assay to evaluate the presence of GBV-C/HGV RNA. A "TaqMan" assay using primers and probe derived from the 5¢ NCR region was developed and validated. Two hundred and fifty-three plasma samples from HIV-infected women were tested for GBV-C viremia and antibody against the envelope protein 2. GBV-C RNA was detected in 22.5% of the patients whereas the antibody was identified in 25.3% of the cohort. Detection of viral RNA and of antibodies was mutually exclusive. Viral loads showed a mean of 1,777 arbitrary units / mL, being 1.1 and 13,625 arbitrary units / mL respectively the lowest and highest values measured. We conclude that the real-time quantitative polymerase chain reaction method developed is appropriate for the investigation of GBV-C RNA since it was shown to be highly specific and sensitive, as well as requiring few steps, preventing contamination and providing additional information as to the relative viremia of carriers, a parameter that must be included in studies evaluating the co-factors influencing the clinical outcome of HIV/AIDS.

‣ Desenvolvimento de uma técnica molecular para detecção e quantificação do vírus da hepatite G (GBV-C/HGV); The Hepatitis G (GBV-C / HGV) agent is a flavivirus

Silva, Synara Alexandre Araujo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 01/06/2010 Português
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Introdução: O vírus da hepatite G (GBV-C/HGV) é um flavivírus de genoma RNA de fita simples polaridade positiva, replicando em linfócitos, não sendo até hoje associado a qualquer patogenia humana. Estudos recentes demonstram que pessoas co-infectadas pelos vírus GBV-C/HGV e HIV têm menor progressão para AIDS e morte, embora alguns estudos tenham falhado em demonstrar tais efeitos. Objetivo: Determinar a soroprevalência e viremia (qualitativa) por GBV-C/HGV nas amostras de pacientes HIV+ e desenvolver uma metodologia de PCR em tempo real para fazer a determinação das cargas virais de GBV-C/HGV. Métodos: Avaliamos a presença de anticorpo e RNA do vírus GBV-C/HGV em 253 amostras de plasma de mulheres HIV positivas, coletadas entre 1997-99. Realizamos o ensaio imunoenzimático anti-E2 (EIA anti-HGenv kit, Roche(TM)), a reação em cadeia da polimerase (PCR), o NESTED PCR e, padronizamos um PCR em tempo real (RT-PCR), ensaio baseado no sistema Taqman, também aplicado nas mesmas amostras. A curva-padrão do ensaio foi feita com diluições seriadas de uma bolsa de plasma GBV-C/HGV+, e os resultados expressos em unidades aleatórias/mL. Resultados: Das 253 amostras testadas, 64 foram positivas para o anticorpo anti-E2 (25...

‣ A influência do vírus da hepatite G (GBV-C) na evolução da infecção pelo HIV em mulheres; Hepatitis G (GBV-C) influence in the prognosis of HIV- infected women

Campos, Aléia Faustina
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/10/2010 Português
Relevância na Pesquisa
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INTRODUÇÃO: O vírus da hepatite G (GBV-C) foi descoberto simultaneamente por dois grupos de pesquisa que buscavam identificar um agente causador de hepatite pós-transfusional não-A, não-B e não-C. Trata-se de um vírus linfotrópico que replica primariamente em células mononucleares do sangue periférico (PBMC), baço e medula óssea, sendo a replicação hepática menos importante. Sabe-se que, após um período de viremia assintomática, a maioria dos carreadores virais clareia o vírus ao longo do tempo havendo surgimento do anticorpo contra a glicoproteína do envelope viral, anti-E2. Uma vez que, provavelmente, não exista nenhuma associação entre o GBV-C e qualquer doença identificada até o momento, o mesmo tem sido considerado um vírus humano não patogênico. Entretanto, alguns estudos demonstraram haver uma interação benéfica entre o GBV-C e HIV a ponto de retardar a progressão da infecção pelo HIV para aids. OBJETIVOS: Avaliar a prevalência da viremia e de anticorpos contra a glicoproteína anti-E2 e estudar o efeito da interação GBV-C e HIV ao longo do acompanhamento de pacientes femininas baseado em valores da média e mediana de linfócitos T CD4+ , da carga viral do HIV e da carga viral quantitativa do GBV-C RNA. MÉTODOS: Foram estudas 248 pacientes femininas portadoras da infecção pelo HIV acompanhadas por um período de cerca de 10 anos...

‣ Genotype distribution of the GB virus C in citizens of São Paulo City, Brazil

Nishiya,Anna S.; Ribeiro-Dos-Santos,Gabriela; Bassit,Leda; Focaccia,Roberto; Chamone,Dalton F.; Sabino,Ester C.
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2003 Português
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There has been several studies worldwide on phylogenetics and genotype distribution of the GB-virus C / Hepatitis G virus (GBV-C/HGV). However, in their great majority, those investigations were based on some epidemiologically linked group, rather than on a representative sampling of the general population. The present is a continuation of the first study in Brazil with such a population; it addresses the GBV-C/HGV phylogenetics and genotype distribution based on samples identified among more than 1,000 individuals of the city of São Paulo. For this purpose, a 728 bp fragment of the 5´non-coding region (5´NCR) of the viral genome, from 24 isolates, was sequenced and subjected to phylogenetic analysis. Genotypes 1, 2a and 2b were found at 8.3% (2/24), 50% (12/24) and 41.7% (10/24), respectively. In conclusion São Paulo displays a genotype distribution similar to the published data for other States and Regions of Brazil, endorsing the notion that types 1 and 2 would have entered the country with African and European people, respectively, since its earliest formation.

‣ Evaluation of GBV-C / HVG viremia in HIV-infected women

Silva,Synara Araújo; Rodrigues,Célia Lima; Campos,Aléia Faustino; Levi,José Eduardo
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2012 Português
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The present study aimed at standardizing a real-time quantitative polymerase chain reaction assay to evaluate the presence of GBV-C/HGV RNA. A "TaqMan" assay using primers and probe derived from the 5¢ NCR region was developed and validated. Two hundred and fifty-three plasma samples from HIV-infected women were tested for GBV-C viremia and antibody against the envelope protein 2. GBV-C RNA was detected in 22.5% of the patients whereas the antibody was identified in 25.3% of the cohort. Detection of viral RNA and of antibodies was mutually exclusive. Viral loads showed a mean of 1,777 arbitrary units / mL, being 1.1 and 13,625 arbitrary units / mL respectively the lowest and highest values measured. We conclude that the real-time quantitative polymerase chain reaction method developed is appropriate for the investigation of GBV-C RNA since it was shown to be highly specific and sensitive, as well as requiring few steps, preventing contamination and providing additional information as to the relative viremia of carriers, a parameter that must be included in studies evaluating the co-factors influencing the clinical outcome of HIV/AIDS.

‣ HEV, TTV and GBV-C/HGV markers in patients with acute viral hepatitis

Lyra,A.C.; Pinho,J.R.R.; Silva,L.K.; Sousa,L.; Saraceni,C.P.; Braga,E.L.; Pereira,J.E.; Zarife,M.A.S.; Reis,M.G.; Lyra,L.G.C.; Silva,L.C. da; Carrilho,F.J.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2005 Português
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The aim of the present study was to evaluate the prevalence of HEV, TTV and GBV-C/GBV-C/HGV in patients with acute viral hepatitis A, B and non-A-C. We evaluated sera of 94 patients from a sentinel program who had acute hepatitis A (N = 40), B (N = 42) and non-A-C (N = 12); 71 blood donors served as controls. IgM and anti-HEV IgG antibodies were detected by enzyme immunoassay using commercial kits. TTV and GBV-C/HGV were detected by nested PCR; genotyping was done by sequencing and phylogenetic analysis. Anti-HEV IgG was present in 38, 10 and 17% of patients with hepatitis A, B and non-A-C. Four patients with hepatitis A and 1 with non-A-C hepatitis also had anti-HEV IgM detected in serum. TTV was detected in 21% of patients with acute hepatitis and in 31% of donors. GBV-C/HGV was detected in 9% of patients with hepatitis, and in 10% of donors. We found TTV isolates of genotypes 1, 2, 3, and 4 and GBV-C/HGV isolates of genotypes 1 and 2. Mean aminotransferase levels were lower in patients who were TTV or GBV-C/HGV positive. In conclusion, the detection of anti-HEV IgM in some acute hepatitis A cases suggests co-infection with HEV and hepatitis E could be the etiology of a few cases of sporadic non-A-C hepatitis in Salvador, Brazil. TTV genotype 1...

‣ GBV-C/HGV and HIV-1 coinfection

Maidana,Maria Teresa; Sabino,Ester Cerdeira; Kallas,Esper Georges
Fonte: Brazilian Society of Infectious Diseases Publicador: Brazilian Society of Infectious Diseases
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2005 Português
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An interesting interaction pattern has been found between HIV-1 and GBV-C/HGV, resulting in protection against progression to AIDS. The mechanisms involved in this interaction remain to be clarified. We examined the current knowledge concerning this coinfection and developed hypotheses to explain its effects. A better understanding of this interaction could result in new concepts, which may lead to new strategies to control HIV-1 replication and progression to AIDS.

‣ Effect of Primer Selection on Estimates of GB Virus C (GBV-C) Prevalence and Response to Antiretroviral Therapy for Optimal Testing for GBV-C Viremia

Souza, I. E.; Allen, J. B.; Xiang, J.; Klinzman, D.; Diaz, R.; Zhang, S.; Chaloner, K.; Zdunek, D.; Hess, G.; Williams, C. F.; Benning, L.; Stapleton, J. T.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /09/2006 Português
Relevância na Pesquisa
58.670127%
GB virus C (GBV-C; also called hepatitis G virus) is a common cause of infection associated with prolonged survival among HIV-infected individuals. The prevalences of GBV-C viremia vary widely in different studies, and there has been poor agreement among different laboratories performing GBV-C RNA detection in quality control studies. To determine the optimal method of measuring GBV-C RNA in clinical samples, samples obtained from 939 HIV-infected subjects were studied using reverse transcription (RT)-PCR methods amplifying four separate regions of the GBV-C genome. Primers amplifying the E2 coding region were 100% specific; however, their sensitivity was only 76.6%. In contrast, primers amplifying three additional conserved regions of the GBV-C genome (the 5′ nontranslated region and the nonstructural protein-coding regions 3 and 5A) were more sensitive but produced higher rates of false-positive results. Using low-specificity primer sets influenced the significance of association between GBV-C viremia and response to antiretroviral therapy. Using a quantitative GBV-C RNA method, the GBV-C RNA concentration did not correlate with baseline or set point HIV RNA levels; however, a correlation between negative, low, and high GBV-C RNA levels and increasing reduction in HIV RNA following antiretroviral therapy was observed. Subjects with both GBV-C E2 antibody and viremia had significantly lower GBV-C RNA levels than did viremic subjects without E2 antibody. These studies demonstrate that accurate detection of GBV-C RNA by nested RT-PCR requires the use of primers representing multiple genome regions. Analyses based on testing with single primers do not lead to reliable conclusions about the association between GBV-C infection and clinical outcomes.

‣ Prevalence of TTV DNA and GBV-C RNA in patients with systemic sclerosis, rheumatoid arthritis, and osteoarthritis does not differ from that in healthy blood donors

Seemayer, C; Viazov, S; Neidhart, M; Bruhlmann, P; Michel, B; Gay, R; Roggendorf, M; Gay, S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/2001 Português
Relevância na Pesquisa
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OBJECTIVE—To determine the prevalence of GB virus-C (GBV-C) RNA and TT virus (TTV) DNA in patients with systemic sclerosis (SSc), rheumatoid arthritis (RA), and osteoarthritis (OA) as well as to compare the autoantibody pattern in patients with SSc with and without evidence of viral infection.
PATIENTS AND METHODS—The study included 168 patients (84 SSc, 41 RA, and 43 OA) diagnosed according to the American College of Rheumatology criteria and 122 volunteer blood donors. The presence of GBV-C RNA and TTV DNA in serum was assessed by nested reverse transcriptase-polymerase chain reaction (RT-PCR) and semi-nested PCR, respectively. Autoantibodies in patients with SSc were determined by enzyme linked immunosorbent assay (ELISA) and Hep-2 immunofluorescence.
RESULTS—TTV-DNA was detected in 10/84 (12%) patients with SSc, 9/41 (22%) patients with RA, 3/43 (7%) patients with OA, and 16/122 (13%) blood donors. GBV-C RNA was present in 4/84 (5%) patients with SSc, 2/43 (5%) patients with OA, and 5/122 (4%) blood donors. No patient with RA was positive for GBV-C RNA. One patient with SSc and one patient with OA showed a double infection with GBV-C and TTV. 74/84 (88%) patients with SSc were positive for at least one autoantibody species tested: 18/84 (21%) showed anticentromeric autoantibodies...

‣ Down-regulation of intra-hepatic T-cell signaling associated with GB virus C in a HCV/HIV co-infected group with reduced liver disease

Berzsenyi, M.; Woollard, D.; McLean, C.; Preiss, S.; Perreau, V.; Beard, M.; Bowden, D.; Cowie, B.; Li, S.; Mijch, A.; Roberts, S.
Fonte: Elsevier BV Publicador: Elsevier BV
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
Relevância na Pesquisa
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BACKGROUND & AIMS: Studies have shown that GB virus C (GBV-C) infection leads to reduced liver disease in hepatitis C virus (HCV)/human immunodeficiency virus (HIV) co-infection. Considering that the underlying mechanism(s) are unknown, we aim to identify differential gene and protein expression associated with GBV-C in HCV/HIV co-infection that may be responsible for reduced liver disease. METHODS: Liver, peripheral blood mononuclear cells (PBMCs), and plasma samples were collected from 43 HCV/HIV patients. Plasma was tested for GBV-C RNA by RT-PCR with NS5B gene primers. A microarray was performed on the liver and RT-qPCRs on the liver/PBMC samples. Hepatic protein expression was measured by immunohistochemistry. RESULTS: Sixteen out of 43 patients had GBV-C RNA. GBV-C was associated with reduced hepatic fibrosis (p=0.005) and inflammation (p=0.007). The microarray analysis of the liver samples (n=10) showed down-regulation of genes critical to intra-hepatic T-cell signaling associated with GBV-C. Quantitative RT-PCR of the liver samples (n=13) confirmed the down-regulation of lymphocyte-specific protein tyrosine kinase (LCK) (p=0.02) and docking protein 2 (DOK2) (p=0.04). No differences in the expression levels of these genes were observed in PBMCs (n=22) according to the GBV-C status. The hepatic expression of the LCK protein...

‣ Frequency and genotypic distribution of GB virus C (GBV-C) among Colombian population with Hepatitis B (HBV) or Hepatitis C (HCV) infection

ALVARADO-MORA, Monica V.; Lima, Livia de Souza Botelho; NISHIYA, Anna; AZEVEDO NETO, Raymundo; GOMES GOUVEA, Michele S.; GUTIERREZ, Maria F.; CARRILHO, Flair J.; PINHO, Joao R. R.
Fonte: BIOMED CENTRAL LTD; LONDON Publicador: BIOMED CENTRAL LTD; LONDON
Tipo: Artigo de Revista Científica
Português
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Background: GB virus C (GBV-C) is an enveloped positive-sense ssRNA virus belonging to the Flaviviridae 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. Methods: Two groups were analyzed: i) 408 Colombian blood donors infected with HCV (n = 250) and HBV (n = 158) from Bogota 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. Results: 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%)...

‣ Detection of GBV-C/HGV RNA in cervico-vaginal smears from healthy individuals

Watanabe,Maria Angelica Ehara; Miquelão,Ana Karina Melim Benthien; Oliveira,Carlos Eduardo Coral de; Oliveira,Karen Brajão de; Nasser,Thiago Franco; Aoki,Mateus Nóbrega; Suzuki,Patrícia Sayuri; Amarante,Marla Karine; Venâncio,Emerson José; Azevedo,E
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2008 Português
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68.47519%
The purpose of the present study was to evaluate the sexual transmission of GBV-C/HGV, through RNA detection in cervicovaginal smears. Therefore the GBV-C/HGV RNA in cervicovaginal smears from apparently healthy women was investigated using routine proceedings for prophylactic screening to cervical cancer. GBV-C/HGV RNA was detected by reverse transcriptase and polymerase chain reaction (RT-PCR). Only one woman presented co-infection with human papilloma virus (HPV). The GBV-C/HGV RNA was detected in 13/73 (17.57%) healthy women and it's prevalence in participating women between 28-43 years old was 53.85%. No association was found with GBV-C/HGV for the age of first sexual intercourse and number of pregnancies. In GBV-C/HGV RNA positive women, 69.23% were married. In conclusion, the present findings show that cervical and vaginal specimens could contain the GBV-C/HGV RNA.

‣ Antigenicity of chimeric and cyclic synthetic peptides based on nonstructural proteins of GBV-C/HGV

Pérez, Teresa; Ercilla, Guadalupe; Chan, Weng C.; Haro Villar, Isabel
Fonte: European Peptide Society; John Wiley & Sons Publicador: European Peptide Society; John Wiley & Sons
Tipo: Artículo Formato: 311795 bytes; application/pdf
Português
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12 pages, 7 figures.-- PMID: 16180243 [PubMed].-- Available online Sep 23, 2005.; In this work, new putative epitopes located in nonstructural proteins of GBV-C/HGV were synthesized using solid-phase chemistry for their use in immunoassays. The antigens were obtained in linear, chimeric and cyclic forms with the main aim of improving the sensitivity of the enzyme immunoassays. Our results showed, on one hand, that the combination of different antigens seems to be necessary to ensure good sensitivity and more specificity and, on the other hand, that cyclic compounds show higher ability to recognize anti-GBV-C/HGV antibodies than its parent peptide. Furthermore, CD and FTIR have been used in conjunction to characterize the conformational changes therein with synthetic constructs that could explain their different antigenicity.; This work was supported by the MCYT Project BQU2003-0507-CO2-02. Teresa Pérez acknowledges the CSIC I3P postgraduate scholarship program for financial support.; Peer reviewed

‣ Interaction of synthetic peptides corresponding to hepatitis G virus (HGV/GBV-C) E2 structural protein with phospholipid vesicles

Larios, Cristina; Christiaens, Bart; Gómara Elena, María José; Alsina, M. Asunción; Haro Villar, Isabel
Fonte: Blackwell Publishing Publicador: Blackwell Publishing
Tipo: Artículo Formato: 22195 bytes; application/pdf
Português
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11 pages, 7 figures, 2 tables.-- PMID: 15885095 [PubMed].-- Printed version published May 2005.; The interaction with phospholipid bilayers of two synthetic peptides with sequences corresponding to a segment next to the native N-terminus and an internal region of the E2 structural hepatitis G virus (HGV/GBV-C) protein [E2(7–26) and E2(279–298), respectively] has been characterized. Both peptides are water soluble but associate spontaneously with bilayers, showing higher affinity for anionic than zwitterionic membranes. However, whereas the E2(7–26) peptide is hardly transferred at all from water to the membrane interface, the E2(279–298) peptide is able to penetrate into negatively charged bilayers remaining close to the lipid/water interface. The nonpolar environment clearly induces a structural transition in the E2(279–298) peptide from random coil to α-helix, which causes bilayer perturbations leading to vesicle permeabilization. The results indicate that this internal segment peptide sequence is involved in the fusion of HGV/GBV-C to membrane.; This work was funded by grants BQU2003-05070-CO2-01/02 from the Ministerio de Ciencia y Tecnología (Spain) and a predoctoral grant awarded to C. L.; Peer reviewed

‣ Distribuição dos genótipos do vírus GB-C (HGV) em indivíduos da cidade de São Paulo, Brasil; Genotype distribution of the GB virus C in citizens of São Paulo City, Brazil

Nishiya, Anna S.; Ribeiro-Dos-Santos, Gabriela; Bassit, Leda; Focaccia, Roberto; Chamone, Dalton F.; Sabino, Ester C.
Fonte: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo Publicador: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/08/2003 Português
Relevância na Pesquisa
68.234688%
Há na literatura vários estudos filogenéticos e de distribuição de genótipos do chamado "Vírus GB-C" ou da "Hepatite G", mais conhecido pela dupla sigla "GBV-C/HGV". Ocorre que, em sua grande maioria, estas pesquisas foram realizadas com amostras de grupos ligados epidemiologicamente e não com indivíduos representativos da população geral. O presente estudo é uma continuação do primeiro trabalho no Brasil feito com este tipo de amostragem. Trata-se de análise filogenética e distribuição genotípica do GBV-C/HGV a partir de amostras isoladas dentre mais de 1.000 indivíduos da cidade de São Paulo. Para tanto, um fragmento de 728 pares de base da região 5' não-codificadora (5´NCR) do genoma viral, de 24 amostras, foi sequenciado e submetido à analise filogenética. Foram identificados os genótipos 1, 2a e 2b nas respectivas freqüências: 8,3% (2/24), 50% (12/24) e 41,7% (10/24). Concluindo, São Paulo apresenta uma distribuição de genótipos semelhante à publicada para outros estados e regiões do Brasil, endossando a idéia de que os tipos 1 e 2 teriam vindo com os africanos e europeus, respectivamente, e portanto estariam na população do país desde a sua formação.; There has been several studies worldwide on phylogenetics and genotype distribution of the GB-virus C / Hepatitis G virus (GBV-C/HGV). However...

‣ Avaliação da viremia por GBV-C/HGV em mulheres infectadas pelo HIV; Evaluation of GBV-C / HVG viremia in HIV-infected women

Silva, Synara Araújo; Rodrigues, Célia Lima; Campos, Aléia Faustino; Levi, José Eduardo
Fonte: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo Publicador: Universidade de São Paulo. Instituto de Medicina Tropical de São Paulo
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/02/2012 Português
Relevância na Pesquisa
68.47519%
Este estudo teve como objetivo o desenvolvimento de método de PCR em Tempo Real para a determinação da viremia do vírus GBV-C. Ensaio baseado em primers e sonda "TaqMan" derivados da região 5' não-codificante deste vírus foi padronizado, validado e aplicado em uma série de 253 amostras de plasma de pacientes HIV+. Além do PCR em tempo real, as amostras foram submetidas a um ensaio imunoenzimático anti-E2 e a um nested-PCR. Das 253 amostras testadas, 64 foram positivas para o anticorpo anti-E2 (25,3%), enquanto 57 amostras foram concordantemente RNA positivas pelo nested-PCR e PCR em tempo real (22,5%), perfazendo um índice total de exposição de 48% (25.3 + 22.5). A carga viral teve média de 1.777 UA/mL (13.625 - 1.1UA/mL). Foi obtida metodologia simples, rápida e de boa sensibilidade e especificidade, permitindo a quantificação do RNA do vírus GBV-C com reprodutibilidade. A metodologia permite a análise simultânea de grande número de amostras, sendo apropriada para estudos clínicos. A prevalência de exposição a este agente na população feminina HIV+ estudada é alta, provavelmente decorrente da via sexual comum de transmissão dos agentes.; The present study aimed at standardizing a real-time quantitative polymerase chain reaction assay to evaluate the presence of GBV-C/HGV RNA. A "TaqMan" assay using primers and probe derived from the 5¢ NCR region was developed and validated. Two hundred and fifty-three plasma samples from HIV-infected women were tested for GBV-C viremia and antibody against the envelope protein 2. GBV-C RNA was detected in 22.5% of the patients whereas the antibody was identified in 25.3% of the cohort. Detection of viral RNA and of antibodies was mutually exclusive. Viral loads showed a mean of 1...

‣ Virus GB-C: ausencia de asociación con niveles de transaminasas, CD4 y carga vírica en pacientes con sida

López Calvo,S; Vela,A; Castro,A; Cid,A; Aguilera,A; Vega,P; Hermida,M; Regueiro,B. J.; Pedreira,J. D.
Fonte: Anales de Medicina Interna Publicador: Anales de Medicina Interna
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/04/2003 Português
Relevância na Pesquisa
58.666123%
Objetivo: Conocer la prevalencia del RNA-GBV-C en pacientes VIH positivos y determinar si existen diferencias entre VHG positivos y negativos en cuanto a situación inmunológica y afectación hepática. Métodos: Se determinó la presencia de RNA-GBV-C en el suero de 222 pacientes VIH positivos mediante una RT-PCR semi-automatizada. Se compararon los pacientes RNA-GBV-C positivos con los negativos en relación a una serie de parámetros clínicos y analíticos. La misma comparación se realizó de forma particular entre aquellos coinfectados con el VHC y GBV-C y los que sólo presentaban el GBV-C Resultados: La prevalencia del RNA-GBV-C fue del 28,8%. El virus hepatotropo más frecuente fue el VHC con el 71,6% de los casos. El 17% presentaban coinfección VHC y GBV-C y el 8,6% solo tenían el GBV-C. Los pacientes con RNA- GBV-C positivo tenían características clínicas y analíticas similares a los RNA-GBV-C negativos. Entre coinfectados VHC-GBV-C y los que presentaban el GBV-C como único virus se observó que el grupo de coinfectados presentó alteración de transaminasas y predominio de la transmisión parenteral como factor de riesgo para la infección VIH, frente al grupo GBV-C que presentó transaminasas normales y predominio de la transmisión sexual. No hubo diferencias entre ambos grupos en cuanto a la media de CD4 y cifras de RNA-VIH. Conclusiones: La positividad del RNA-GBV-C en pacientes VIH no influye en la presencia de enfermedad hepática que viene determinada en estos pacientes por la frecuente coinfección con otros virus hepatotropos. Tampoco parece influir en la viremia del VIH ni en la cifra de CD4.