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Objective To perform a meta-analysis on the association of of genotype B/C and HBV DNA conversion of negative or HBeAg clearance to lamivudine therapy.Methods Several databases (PubMed, Web of Science, Science Direct, and CNKI Database) were searched from 1966 to 2012 for all publications on the association between genotype B/C and response to LAM therapy.The articles were selected according to the protocol previously designed.Meta analysis using Revman 5 software.Results Finally, 19 RCTs were retrieved involving 3148 patients for the subsequent meta-analysis. Among them, 10 articles (n=1860) look at HBV DNA and 9 (n=1288) at HbeAg clearance.For HBV DNA conversion of negative, the overall RR (95% CI) associated with genotype B/C was 1.07(0.98-1.17). Of the nine analyzed trials, HBeAg clearance was observed in genotype B group as compared with that genotype C group, the overall RR (95% CI) was 1.27 (0.94-1.71).Conclusion Meta-analysis indicates that genotype B/C is not associated with response to LAM therapy.Further mechanism researches are required to clarify.Large-scale population studies in multicountries are also necessary to evaluate the influence of HBV genotypes in hepatitis B progression and antiviral treatment.
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Objective To construct 1.3-fold-overlength infectious clone of hepatitis B virus isolated from Chinese patients , observe the expression of plasmid in Huh7 of liver cancer cells and establish genome of HBV in vitro. Methods HBV DNA in serum was extracted from HBV patient. SOE-PCR was performed to produce a 1.3-fold-overlength genome of HBV. The plasmid was named pHBV1.3 (C). After that,pHBV1.3 (C) was transfected into Huh7 cells, HBV related viral antigens and DNA were detected by ELISA,Western Blot and Fluorescence quantitative PCR. Furthermore, adefovir dipivoxil, a clinic anti-viral drug, was utilized to test the sensitivity of the new infectious clone. Results An infectious clone of pHBV1.3 (C) was successfully constructed. HBV gene carried in pHBV1.3 (C) could be efficiently replicated and expressed in Huh7 cells. Adefovir could inhibit HBV replication in this HBV cell model. Conclusions A recombinant plasmid containing 1.3-fold-overlength of HBV genotype C was successfully constructed. This construct is competent to support viral transcription and replication in vitro , suggesting that infectious cells are expected to be a new model of HBV infection in vitro.
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Despite the effectiveness of current hepatitis B virus (HBV) vaccines, it is estimated that 350 million individuals suffer from chronic HBV infection and more than 50% of these affected individuals live on the Asian continent. Panama is a country with a great diversity of foreign groups; the Chinese community is a large example of this phenomenon. There is an urgent need to perform studies that evaluate the prevalence and the genetic diversity of HBV in this community. This study aimed to evaluate the prevalence of HBV and its genotypes and mutant variants in the Chinese population residing in Panama. In total, 320 subjects were enrolled in the study. Forty-two subjects (13.1%) were positive for HBsAg and HBV-DNA from 18 subjects revealed the presence of genotypes B2 and C1. Secondary mutations associated with drug resistance at positions rtV207L and rtN239T of the reverse transcriptase gene were identified. Additionally, the mutation pair A1762T/G1764A was found in three samples and the mutation G1896A was detected in an HBeAg-negative subject. In conclusion, to our knowledge, this is the first study to report high HBV prevalence rates in resident ethnic Chinese in Central America and the presence of genotypes B2 and C1 in this region.
Subject(s)
Adolescent , Adult , Aged , Child , Female , Humans , Male , Middle Aged , Young Adult , Hepatitis B virus/genetics , Hepatitis B/virology , China/ethnology , DNA, Viral/genetics , Genotype , Hepatitis B Surface Antigens/blood , Hepatitis B/ethnology , Hepatitis B/immunology , Mutation , Panama , Sequence Analysis, DNAABSTRACT
Measles, mumps and rubella (MMR) vaccine failure had been reported globally and here, we report that it occurs in India now. MMR vaccinated people have developed acute mumps accompanied by anti-mumps immunoglobulin M. Genotypic characterisation revealed that the circulating mumps strain was genotype C, which is distinct from the vaccine strain of genotype N (L-Zagreb). This is the first report in India to suggest that genotype C is responsible for the present mumps infection. Thus, the present MMR vaccine must be revamped and optimised for its efficacy to prevent any future mumps epidemics.
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The hepatitis B virus (HBV) is among the leading causes of chronic hepatitis, cirrhosis and hepatocellular carcinoma. In Brazil, genotype A is the most frequent, followed by genotypes D and F. Genotypes B and C are found in Brazil exclusively among Asian patients and their descendants. The aim of this study was to sequence the entire HBV genome of a Caucasian patient infected with HBV/C2 and to infer the origin of the virus based on sequencing analysis. The sequence of this Brazilian isolate was grouped with four other sequences described in China. The sequence of this patient is the first complete genome of HBV/C2 reported in Brazil.
Subject(s)
Female , Humans , Middle Aged , Genome, Viral , Hepatitis B virus , Hepatitis B, Chronic , Brazil , DNA, Viral , Genotype , Hepatitis B virusABSTRACT
Objective To detect the recombinant intermediates of hepatitis B virus (HBV) between genotype B and C in vitro. Methods Vector Plenti6/V5-D-topo-X was genetically modified by genotype B and C to transfect HepG2 cells. Then the HepG2 cells were amplified and sequence of the nucleic acid after the transinfection was tested and compared with RDP3Beta40 software package and bootscanning procedure in SimPlot program package. Results Three recombinant intermediates of HBV between genotype B and C were identified in vitro. Genotype C in the precore region plus the core gene spanning nucleotide positions from 1740-1838 to 2443-2485 contributed to the recombination with genotype B. Isolate R1 recombinant intermediate had 2 break points at nt2170-2172 and nt2188-2189. Nucleic acid changed from CAC to TGT and from GA to AC, respectively. Isolate R2 recombinant intermediate had a break point at nt1740-1 838, and 3 bases changed in different nucleic acid sites: from A to T at nt1740, from C to T at nt1753, and from G to A at nt1838, respectively. Isolate R3 recombinant intermediate had a break point at nt2443-2483, and 4 bases changed in different nucleic acid sites: from C to T at nt2443, from A to G at nt2452, from T to C at nt2480, and from C to T at nt2483, respectively. Conclusion The recombinant intermediates of HBV between genotype B and C have been detected in vitro and the changes have been identified in the precore region plus the core gene in genotype B and C.
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Enterovirus 71 (EV71) is a common cause of Hand, foot, and mouth disease (HFMD) and may also cause severe neurological diseases, such as encephalitis and poliomyelitis-like paralysis. To examine the genetic diversity of EV71, we determined and analyzed the complete VP1 sequences (891 nucleotides) from nine EV71 strains isolated in Fuyang, China. We found that nine EV71 strains isolated were over 98% homologous at the nucleotide level and 93%-100% homologous to members of the C4 subgenogroup. At the amino acid level, these Fuyang strains were 99% -100% homologous to one another, 97%-100% homologous to members of the C4 subgenogroup, and the histidine(H) at amino acid position 22 was conserved among the Fuyang strains. The results indicate that Fuyang isolates belong to genotype C4, and an H at position 22 appears to be a marker for the Fuyang strains.