JOAO RENATO REBELLO PINHO

(Fonte: Lattes)
Índice h a partir de 2011
28
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/07 - Laboratório de Gastroenterologia Clínica e Experimental, Hospital das Clínicas, Faculdade de Medicina
LIM/03 - Laboratório de Medicina Laboratorial, Hospital das Clínicas, Faculdade de Medicina

Resultados de Busca

Agora exibindo 1 - 3 de 3
  • article 1 Citação(ões) na Scopus
    Epidemiology, virology and pathogenesis of viral hepatitis with a focus on Latin America
    (2013) PINHO, Joao R. Rebello; ALVARADO-MORA, Monica V.; LOCARNINI, Stephen
  • article 65 Citação(ões) na Scopus
    An update on HDV: virology, pathogenesis and treatment
    (2013) ALVARADO-MORA, Monica V.; LOCARNINI, Stephen; RIZZETTO, Mario; PINHO, Joao R. Rebello
    Hepatitis delta is an inflammatory liver disease caused by infection with HDV. HDV is a single-stranded circular RNA pathogen with a diameter of 36 nm. HDV is classified in the genus Deltavirus and is still awaiting a final taxonomic classification up to the family level. HDV shares similarities with satellite RNA and viroids including a small circular single-stranded RNA with secondary structure that replicates through the 'double rolling circle' mechanism. The HDV RNA genome is capable of self-cleavage through a ribozyme and encodes only one structural protein, the hepatitis delta antigen (HDAg), from the antigenomic RNA. There are two forms of HDAg, a shorter (S; 22 kDa) and a longer (L; 24 kDa) form, the latter generated from an RNA editing mechanism. The S form is essential for viral genomic replication. The L form participates in the assembly and formation of HDV. For complete replication and transmission, HDV requires the hepatitis B surface antigen (HBsAg). Thus, HDV infection only occurs in HBsAg-positive individuals, either as acute coinfection in treatment-naive HBV-infected persons, or as superinfection in patients with pre-existing chronic hepatitis B (CHB). HDV is found throughout the world, but its prevalence, incidence, clinical features and epidemiological characteristics vary by geographic region. There are eight genotypes (1 to 8) distributed over different geographic areas: HDV-1 is distributed worldwide, whereas HDV-2 to 8 are seen more regionally. Levels of HDV viraemia change over the course of HDV infection, being significantly higher in patients with early chronic hepatitis than in cirrhosis. Chronic HDV infection leads to more severe liver disease than chronic HBV monoinfection with an accelerated course of fibrosis progression, an increased risk of hepatocellular carcinoma and early decompensation in the setting of established cirrhosis. Current treatments include pegylated interferon-alpha and liver transplantation; the latter of which can be curative. Further studies are needed to develop better treatment strategies for this challenging disease.
  • article 20 Citação(ões) na Scopus
    Phylogenetic Analysis of Hepatitis B Virus Genotype F Complete Genome Sequences From Chilean Patients With Chronic Infection
    (2011) VENEGAS, Mauricio; ALVARADO-MORA, Monica V.; VILLANUEVA, Rodrigo A.; PINHO, Joao R. Rebello; CARRILHO, Flair J.; LOCARNINI, Stephen; YUEN, Lilly; BRAHM, Javier
    Molecular epidemiological data concerning the hepatitis B virus (HBV) in Chile are not known completely. Since the HBV genotype F is the most prevalent in the country, the goal of this study was to obtain full HBV genome sequences from patients infected chronically in order to determine their subgenotypes and the occurrence of resistance-associated mutations. Twenty-one serum samples from antiviral drug-naive patients with chronic hepatitis B were subjected to full-length PCR amplification, and both strands of the whole genomes were fully sequenced. Phylogenetic analyses were performed along with reference sequences available from GenBank (n = 290). The sequences were aligned using Clustal X and edited in the SE-AL software. Bayesian phylogenetic analyses were conducted by Markov Chain Monte Carlo simulations (MCMC) for 10 million generations in order to obtain the substitution tree using BEAST. The sequences were also analyzed for the presence of primary drug resistance mutations using CodonCode Aligner Software. The phylogenetic analyses indicated that all sequences were found to be the HBV subgenotype F1b, clustered into four different groups, suggesting that diverse lineages of this subgenotype may be circulating within this population of Chilean patients. J. Med. Virol. 83: 1530-1536, 2011. (C) 2011 Wiley-Liss, Inc.