AIM: To determine whether one genotype (A or non-A genotypes of HBV) predominated over the other during the course of HBV infection.METHODS: Four baboons were inoculated with HBV. DNA was extracted from serum obtained...AIM: To determine whether one genotype (A or non-A genotypes of HBV) predominated over the other during the course of HBV infection.METHODS: Four baboons were inoculated with HBV. DNA was extracted from serum obtained at monthly intervals postinoculation for 52 weeks and HBV DNA was amplified using primers specific for the core region containing an insert characteristic of genotype A (nt 2 354-2 359, numbering from the EcoRI site). The amplicons were cloned into PCRScriptTM and a minimum of 15 clones per time point were sequenced in both directions.RESULTS: Both genotypes persisted for the entire followup period of 52 weeks. Genotype non-A predominated in two baboons and genotype A in one baboon. Neither genotype predominated in the fourth baboon, as shown at a 5 % level of testing.CONCLUSION: No conclusions concerning the dominance of either genotype or the natural progression or replication rates of HBV could be drawn because the pattern of the genotypes found may have been caused by sampling fluctuations at the time of DNA extraction and cloning as a result of the very low viral loads in the baboon sera.展开更多
AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis B core antigen as the only marker of infection （“anti-HBc alone”） among human immunodeficiency virus （HIV） type-1 infe...AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis B core antigen as the only marker of infection （“anti-HBc alone”） among human immunodeficiency virus （HIV） type-1 infected patients. Occult hepatitis B infection frequency was also evaluated. METHODS： Three hundred and forty eight histories from 2388 HIV-positive patients were randomly reviewed. Patients with serological markers of hepatitis B virus （HBV） infection were classified into three groups： past hepatitis, ＂anti-HBc alone＂ and chronic hepatitis. Determination of DNA from HBV, and RNA and genotype from hepatitis C virus （HCV） were performed on ＂anti-HBc alone＂ patients. RESULTS： One hundred and eighty seven （53.7%） HIV-positive patients had markers of HBV infection： 118 past infection （63.1%）, 14 chronic hepatitis （7.5%） and 55 ＂anti-HBc alone＂ （29.4%）. Younger age [2.3-fold higher per every 10 years younger; 95% confidence intervals （Cl） 1.33-4.00] and antibodies to HCV infection [odds ratio （OR） 2.87; 95% CI 1.10-7.48] were factors independently associated with the ＂anti-HBc alone＂ pattern. No differences in liver disease frequency were detected between both groups. Serum levels of anti-HBs were not associated with HCV infection （nor viral replication or HCV genotype）, or with HIV replication or CD4 level. No ＂anti-HBc alone＂ patient tested positive for HBV DNA. CONCLUSION： ＂Anti-HBc alone＂ prevalence in HIM- positive patients was similar to previously reported data and was associated with a younger age and with antibodies to HCV infection. In clinical practice, HBV DNA determination should be performed only in those patients with clinical or analytical signs of liver injury,展开更多
文摘AIM: To determine whether one genotype (A or non-A genotypes of HBV) predominated over the other during the course of HBV infection.METHODS: Four baboons were inoculated with HBV. DNA was extracted from serum obtained at monthly intervals postinoculation for 52 weeks and HBV DNA was amplified using primers specific for the core region containing an insert characteristic of genotype A (nt 2 354-2 359, numbering from the EcoRI site). The amplicons were cloned into PCRScriptTM and a minimum of 15 clones per time point were sequenced in both directions.RESULTS: Both genotypes persisted for the entire followup period of 52 weeks. Genotype non-A predominated in two baboons and genotype A in one baboon. Neither genotype predominated in the fourth baboon, as shown at a 5 % level of testing.CONCLUSION: No conclusions concerning the dominance of either genotype or the natural progression or replication rates of HBV could be drawn because the pattern of the genotypes found may have been caused by sampling fluctuations at the time of DNA extraction and cloning as a result of the very low viral loads in the baboon sera.
文摘AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis B core antigen as the only marker of infection （“anti-HBc alone”） among human immunodeficiency virus （HIV） type-1 infected patients. Occult hepatitis B infection frequency was also evaluated. METHODS： Three hundred and forty eight histories from 2388 HIV-positive patients were randomly reviewed. Patients with serological markers of hepatitis B virus （HBV） infection were classified into three groups： past hepatitis, ＂anti-HBc alone＂ and chronic hepatitis. Determination of DNA from HBV, and RNA and genotype from hepatitis C virus （HCV） were performed on ＂anti-HBc alone＂ patients. RESULTS： One hundred and eighty seven （53.7%） HIV-positive patients had markers of HBV infection： 118 past infection （63.1%）, 14 chronic hepatitis （7.5%） and 55 ＂anti-HBc alone＂ （29.4%）. Younger age [2.3-fold higher per every 10 years younger; 95% confidence intervals （Cl） 1.33-4.00] and antibodies to HCV infection [odds ratio （OR） 2.87; 95% CI 1.10-7.48] were factors independently associated with the ＂anti-HBc alone＂ pattern. No differences in liver disease frequency were detected between both groups. Serum levels of anti-HBs were not associated with HCV infection （nor viral replication or HCV genotype）, or with HIV replication or CD4 level. No ＂anti-HBc alone＂ patient tested positive for HBV DNA. CONCLUSION： ＂Anti-HBc alone＂ prevalence in HIM- positive patients was similar to previously reported data and was associated with a younger age and with antibodies to HCV infection. In clinical practice, HBV DNA determination should be performed only in those patients with clinical or analytical signs of liver injury,
