Home About us Contact
|
Home About us Contact | ||
|
|
||
HBV DNA Concentration (hbv + dna_concentration)
Selected AbstractsRisk factors and mechanism of transplacental transmission of hepatitis B virus: A case-control studyJOURNAL OF MEDICAL VIROLOGY, Issue 1 2002De-Zhong Xu Abstract Intrauterine hepatitis B virus (HBV) infection has been suggested to be caused by transplacental transmission that cannot be blocked by hepatitis B vaccine. This would decrease the effectiveness of hepatitis B vaccine. This study examined the risk factors and mechanism of transplacental HBV transmission. A case-control study included 402 newborn infants from 402 HBsAg-positive pregnant women. Among these, 15 newborn infants infected with HBV by intrauterine transmission were selected as cases, and the rest as controls. A pathology study included 101 full-term placentas from the HBsAg-positive pregnant women above and 14 from HBsAg-negative pregnant women. Immunohistochemistry staining and HBV DNA in situ hybridization were used to estimate the association of intrauterine HBV infection and HBV infection in the placentas. HBeAg positivity in mothers' sera (OR,=,17.07, 95%CI 3.39,86.01) and threatened preterm labor (OR,=,5.44, 95%CI 1.15,25.67) were found to be associated with transplacental HBV transmission. The intrauterine infection rate increased linearly and significantly with maternal serum HBsAg titers (trend test P,=,0.0117) and HBV DNA concentration (trend test P,<,0.01). Results of the pathology study showed that HBV infection rates decreased gradually from the maternal side to the fetal side (trend test P,=,0.0009) in the placental cell layers. There was a significant association between intrauterine HBV transmission and HBV infection in villous capillary endothelial cells (VCEC) in the placenta (OR,=,18.46, P,=,0.0002). The main risk factors for intrauterine HBV infection are maternal serum HBeAg positivity, history of threatened preterm labor, and HBV in the placenta especially the villous capillary endothelial cells. Previous reports of transplacental leakage of maternal blood causing intrauterine infection are confirmed. In addition, there appears to be a "cellular transfer" of HBV from cell to cell in the placenta causing intrauterine infection. This latter hypothesis needs to be confirmed. J. Med. Virol. 67:20,26, 2002. © 2002 Wiley-Liss, Inc. [source] Quantitative detection of hepatitis B virus DNA in serum by a new rapid real-time fluorescence PCR assayJOURNAL OF VIRAL HEPATITIS, Issue 6 2001R. Jardi A sensitive and accurate HBV DNA quantification assay is essential for monitoring hepatitis B virus (HBV) replication. This study evaluated a real-time PCR method performed in the LightCyclerTM analyser for quantitative HBV DNA assay. HBV DNA results with this method were compared with those obtained using a branched-chain DNA (bDNA) solution hybridization assay. Real-time PCR was performed using two adjacent fluorescently labelled probes and primers corresponding to the HBV core gene. The same standard employed in the bDNA assay was used for calibration. Serum samples came from 193 HBV surface antigen (HBsAg)-positive patients (34 HBV e antigen (HBeAg)-positive and 93 with antibody to HBeAg (anti-HBe)), and 66 asymptomatic HBV carriers. In addition, we analysed serum samples from 8 anti-HBe-positive patients who had been receiving lamivudine treatment for more than three years. A linear standard curve was seen in the range from 103 to 108 copies/mL. In the reproducibility analysis, intra-assay coefficient of variation (CVs) at two known HBV DNA concentrations were 4% and 2% and interassay CVs were 6% and 4%. The median of serum HBV DNA by real-time PCR was 9.2 × 108 copies/mL in HBeAg-positive patients with persistently elevated alanine aminotransferase (ALT) levels, 1.3 × 107 copies/mL in anti-HBe-positive cases with persistently elevated ALT levels, 3.7 × 104 copies/mL in anti-HBe-positive patients with fluctuating ALT levels and 104 copies/mL in asymptomatic HBV carriers. The differences in HBV DNA levels among the various groups studied were statistically significant (P < 0.05). The cut-off between chronic hepatitis patients and asymptomatic carriers was found to be at a serum HBV DNA concentration of 5 × 104 copies/mL. Of the 109 serum samples with a viral load < 7.5 × 105 (negative by bDNA assay) 44 (40%) were positive by real-time PCR: 24 (56%) chronic hepatitis and 20 (33%) asymptomatic carriers. There was a positive association between HBV DNA levels determined by real-time PCR and ALT levels (P < 0.05), which was not observed with the bDNA assay for HBV DNA quantification. At 12 months of lamivudine treatment, 6 patients (75%) showed HBV DNA levels < 5 × 104 copies/mL (range < 103,2 × 103), significantly lower than at baseline. At 36 months, 2 of 8 (25%) showed HBV DNA levels persistently lower than 5 × 104 copies/mL (1.7 × 103, 6 × 103). The LightCycler quantitative real-time PCR is a practical, sensitive, reproducible single-tube assay with a wide dynamic range of detection. The assay is automatic except for DNA extraction and the running time is only 70 min. The LightCycler real-time PCR is useful for identifying different states of HBV infection and for evaluating the efficacy of viral therapy. [source] Effects of lamivudine on outcome after liver resection for hepatocellular carcinoma in patients with active replication of hepatitis B virusHEPATOLOGY RESEARCH, Issue 2 2007Shoji Kubo Aim:, Patients with high serum hepatitis B virus (HBV) DNA concentrations are at high risk of tumor recurrence after liver resection for HBV-related hepatocellular carcinoma (HCC). Methods:, Among 24 patients with high serum HBV DNA concentrations who underwent liver resection for HBV-related HCC, postoperative lamivudine therapy was chosen by 14 (lamivudine group). The other 10 patients were controls. Results:, Clinicopathologic findings did not differ between the groups. Tumor-free survival rate after surgery was significantly higher in the lamivudine than the control group (P = 0.0086). By univariate analysis, multiple tumors were also a risk factor for a short tumor-free survival. By multivariate analysis, lack of lamivudine therapy and multiple tumors were independent risk factors for a short tumor-free survival. In four patients YMDD mutant viruses were detected after beginning lamivudine administration; in two of them, adefovir dipivoxil was administered because of sustained serum alanine aminotransferase elevations. Conclusion:, Lamivudine therapy improved tumor-free survival rate after curative resection of HBV-related HCC in patients with high serum concentrations of HBV DNA, although careful follow up proved necessary for the detection of YMDD mutant viruses. [source] Quantitative detection of hepatitis B virus DNA in serum by a new rapid real-time fluorescence PCR assayJOURNAL OF VIRAL HEPATITIS, Issue 6 2001R. Jardi A sensitive and accurate HBV DNA quantification assay is essential for monitoring hepatitis B virus (HBV) replication. This study evaluated a real-time PCR method performed in the LightCyclerTM analyser for quantitative HBV DNA assay. HBV DNA results with this method were compared with those obtained using a branched-chain DNA (bDNA) solution hybridization assay. Real-time PCR was performed using two adjacent fluorescently labelled probes and primers corresponding to the HBV core gene. The same standard employed in the bDNA assay was used for calibration. Serum samples came from 193 HBV surface antigen (HBsAg)-positive patients (34 HBV e antigen (HBeAg)-positive and 93 with antibody to HBeAg (anti-HBe)), and 66 asymptomatic HBV carriers. In addition, we analysed serum samples from 8 anti-HBe-positive patients who had been receiving lamivudine treatment for more than three years. A linear standard curve was seen in the range from 103 to 108 copies/mL. In the reproducibility analysis, intra-assay coefficient of variation (CVs) at two known HBV DNA concentrations were 4% and 2% and interassay CVs were 6% and 4%. The median of serum HBV DNA by real-time PCR was 9.2 × 108 copies/mL in HBeAg-positive patients with persistently elevated alanine aminotransferase (ALT) levels, 1.3 × 107 copies/mL in anti-HBe-positive cases with persistently elevated ALT levels, 3.7 × 104 copies/mL in anti-HBe-positive patients with fluctuating ALT levels and 104 copies/mL in asymptomatic HBV carriers. The differences in HBV DNA levels among the various groups studied were statistically significant (P < 0.05). The cut-off between chronic hepatitis patients and asymptomatic carriers was found to be at a serum HBV DNA concentration of 5 × 104 copies/mL. Of the 109 serum samples with a viral load < 7.5 × 105 (negative by bDNA assay) 44 (40%) were positive by real-time PCR: 24 (56%) chronic hepatitis and 20 (33%) asymptomatic carriers. There was a positive association between HBV DNA levels determined by real-time PCR and ALT levels (P < 0.05), which was not observed with the bDNA assay for HBV DNA quantification. At 12 months of lamivudine treatment, 6 patients (75%) showed HBV DNA levels < 5 × 104 copies/mL (range < 103,2 × 103), significantly lower than at baseline. At 36 months, 2 of 8 (25%) showed HBV DNA levels persistently lower than 5 × 104 copies/mL (1.7 × 103, 6 × 103). The LightCycler quantitative real-time PCR is a practical, sensitive, reproducible single-tube assay with a wide dynamic range of detection. The assay is automatic except for DNA extraction and the running time is only 70 min. The LightCycler real-time PCR is useful for identifying different states of HBV infection and for evaluating the efficacy of viral therapy. [source] | ||||||||||