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1.
Braz. j. microbiol ; 40(4): 965-971, Oct.-Dec. 2009. tab
Article in English | LILACS | ID: lil-528182

ABSTRACT

This study investigated the prevalence of the precore G1896A mutation in Chinese patients with hepatitis B e antigen (HBeAg) negative HBV infection and its relation to serum HBV pre-S1 antigen. The overall prevalence of the precore G1896A mutation was 72.6 percent in HBeAg-negative Chinese patients with detectable serum HBV DNA. The prevalence of the precore G1896A is significantly higher in Chinese HBeAg-negative patients with chronic hepatitis B than that in inactive HBV carriers with detectable serum HBV DNA. Serum pre-S1 and the precore G1896A mutation were simultaneously detected in most of Chinese HBeAg-negative patients.


Subject(s)
Humans , Hepatitis B virus , Hepatitis B, Chronic , Mutation , Prevalence , Virus Diseases , Diagnostic Techniques and Procedures , Methods , Methods
2.
Braz. j. med. biol. res ; 40(12): 1689-1692, Dec. 2007. ilus
Article in English | LILACS | ID: lil-466744

ABSTRACT

Genotype E of hepatitis B virus (HBV) has not been described in Brazil and is found mainly in Africa. Genotype A is the most prevalent in Brazil, and genotypes B, C, D, and F have already been reported. We report here an HBV genotype E-infected patient and some characterization of surface (S) protein, DNA polymerase (P) and precore/core (preC/C) coding regions based on the viral genome. The patient is a 31-year-old black man with chronic hepatitis B who was born and raised in Angola. He has been followed by a hepatologist in São Paulo, Brazil, since November 2003, and he is a frequent traveler to Latin America, Africa, and Europe. In 2003, he was diagnosed with HBV infection and started treatment with lamivudine with the later addition of adefovir dipivoxil. No known risk factor was identified. Serologically, he is HBsAg and anti-HBe positive, but HBeAg and anti-HBs negative. DNA sequence analysis of the S/P region confirmed that this patient is infected with genotype E, subtype ayw4. The preC/C region showed G1896A and G1899A mutations but no mutations in the basal core promoter. Nucleotide substitutions common in genotype E were also observed (C1772, T1858 and A1757). Although this is not an autochthonous case and there is no evidence of further spread, the description of this case in Brazil highlights the current risk of viral genotypes spreading with unprecedented speed due to constant travel around the world.


Subject(s)
Adult , Humans , Male , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Travel , Africa , Brazil , DNA, Viral/blood , Genotype , Hepatitis B Antibodies/blood , Hepatitis B e Antigens/blood , Hepatitis B virus/classification , Hepatitis B, Chronic/diagnosis , Phylogeny , Polymerase Chain Reaction , Viral Load
3.
Rev. Soc. Bras. Med. Trop ; 37(supl.2): 33-39, 2004. ilus, graf, mapas, tab
Article in Portuguese | LILACS | ID: lil-723317

ABSTRACT

A infecção pelo virus da hepatite B apresenta amplo espectro de manifestações clínicas. Objetivando conhecer os genótipos do HBV mais prevalentes e determinar a ocorrência da mutação pré-core A-1896, em uma população da Amazônia oriental, correlacionando com o diagnóstico clínico, foram selecionados 51 pacientes portadores crônicos de HBsAg e HBV-DNA positivos e divididos em três grupos: grupo A (n=14, pacientes assintomáticos); grupo B (n=20, sintomáticos HBeAg positivos) e grupo C (n=17, sintomáticos HBeAg negativos), sendo usado o sequenciador automático ABI modelo 377 para identificação de genótipos e mutantes pré-core. Os resultados evidenciaram o genótipo A como o mais prevalente, 81,8%, 89,5% e 93,7%, nos grupos A, B e C, respectivamente. A mutação pré-core A-1896 foi encontrada em 11,5% (3/26), sendo todos assintomáticos. Concluiu-se que na população estudada o genótipo A foi o mais prevalente e houve baixa ocorrência do mutante pré-core A-1896, ambos não se constituindo fatores agravantes da doença hepática.


Hepatitis B virus (HBV) infection presents itself with a variety of clinical manifestations. The present work aims to describe the prevalence of HBV genotypes and the occurrence of precore mutation A-1896 in a population group of the Eastern Amazon region of Brazil and to correlate them with the clinical presentation of chronic HBV infection. 51 HBsAg carriers (HBV-DNA positive) were selected and divided into three groups: A (14 asymptomatic subjects), B (20 HBeAg positive symptomatic patients) and C (17 HBeAg negative symptomatic patients). Using an automa ed DNA sequencer ABI model 377 by sequencing for determined of genotypes and precore mutation. The results showed that the genotype A was the most commonly found (81,1%, 89,5% and 93,7% in groups A, B and C, respectively) and precore mutation A-1896 was described in 11,5% (3/26) of group A subjects. Genotype A of HBV was the most prevalent (89,1%) and low occurrence of precore mutation A-1896, both not associate with the worst outcome of the chronic infection of HBV.


Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , DNA, Viral/analysis , Hepatitis B Core Antigens/blood , Hepatitis B Surface Antigens/blood , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Mutation , Base Sequence , Brazil , Genotype , Hepatitis B Core Antigens/genetics , Hepatitis B virus/immunology , Molecular Sequence Data , Polymerase Chain Reaction , Prevalence , Viral Load
4.
The Korean Journal of Hepatology ; : 149-156, 2002.
Article in Korean | WPRIM | ID: wpr-109823

ABSTRACT

BACKGROUND/AIMS: Precore and core promoter mutations of hepatitis B virus (HBV) have been reported in Korea but their prevalence and clinical significance have not been determined. The aims of this study were to determine the prevalence of precore and core promoter mutations and their relationships to hepatitis B e antigen (HBeAg) status, viral replication level, and severity of liver disease in Korea. METHODS: Among the patients who visited the Liver Diseases Clinics (Chung Ang University Hospital) between December 1998 and August 1999, 150 patients were randomly selected: 50 HBeAg-positive HBV-DNA positive patients by a branched DNA (bDNA) assay, 50 HBeAg-negative bDNA-positive patients, and 50 HBeAg-negative bDNA-negative patients. Serum HBV-DNA was amplified by a polymerase chain reaction (PCR) in these patients and the core promoter/precore HBV sequence was determined in 135 of the patients whose sera were positive for HBV-DNA by PCR. RESULTS: All of the 135 determined HBV-DNA sequences had HBV genotype with T at nucleotide 1858. Precore mutation (A1896) was detected in 95.7% of HBeAg-negative bDNA-positive patients and 94.9% of HBeAg-negative bDNA-negative patients. In HBeAg-positive patients 88% had wild type and 12% had mixture of wild type and A1896 mutant. Core promoter TA mutation (T1762/A1764) was detected in 93.5% of HBeAg-negative bDNA-positive patients, 94.9% of HBeAg-negative bDNA-negative patients and 74% of HBeAg-positive patients. No correlation was found between the presence of precore/core promoter mutations and liver disease severity or HBV-DNA levels. CONCLUSION: Precore stop codon mutation occurred almost invariably, along with HBeAg seroconversion, irrespective of subsequent viral replication levels or disease severity. Core promoter TA mutation was frequent both in the HBeAg-positive patients and HBeAg-negative patients irrespective of viral replication levels or disease severity.


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , DNA, Viral/analysis , English Abstract , Hepatitis B virus/genetics , Hepatitis B e Antigens/analysis , Hepatitis B, Chronic/virology , Korea , Mutation , Promoter Regions, Genetic/genetics , Sequence Analysis, DNA , Viral Core Proteins/genetics , Viral Load
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