Search results for "Hepatitis B virus DNA polymerase"
showing 10 items of 18 documents
Use of the polymerase chain reaction to demonstrate hepatitis B virus DNA in serum of children with chronic hepatitis B.
1992
The polymerase chain reaction was used to investigate the presence of hepatitis B virus DNA in sera of 61 children with chronic hepatitis B and negative results on dot biot hybridization tests. Our results demonstrate that most chronic carriers of hepatitis B surface antigen in childhood have hepatitis B virus DNA detectable by polymerase chain reaction in their serum and must be considered infectious.
Hepatitis B and C virus variants in long-term immunosuppressed renal transplant patients in Latvia.
2004
The incidence of genome variants of hepatitis B and hepatitis C viruses among 38 long-term (2–15 years) immunosuppressed patients after renal transplantation and 10 patients undergoing dialysis was investigated. Twelve patients had only HBV infection, 9 had only HCV infection and 14 were co-infected. Regions corresponding to the HBV X/EnII/BCP, preC/C, preS/S and to the HCV core were sequenced for molecular characterization of the HBV and HCV genomes. Fifty-seven percent of HBV DNA isolates belonged to genotype D and 42% to genotype A, whereas 77% of HCV RNA isolates belonged to genotype 1b and only 17% to genotype 3a. One sample (6%) was of genotype 2c. Detailed analysis of the above-menti…
Detection of Hepatitis B Virus DNA in the Liver of Children with Chronic Hepatitis B by In Situ Hybridization and Its Relation to Other Viral Markers
1992
The aim of the study was to detect hepatitis B virus (HBV) DNA by in situ hybridization (ISH) with a 35S-labeled radioactive probe in frozen liver biopsy tissue sections of 63 hepatitis B virus surface antigen (HBsAg)-positive children. The results were compared to other markers of viral replication. HBV DNA was detected in 48 children. Of the 15 negative cases, four had hepatitis B envelope antigen (HBeAg), 10 anti-HBe, and one neither HBeAg nor anti-HBe. Free HBV DNA in serum and liver was positive in one patient. Forty of the positive children were HBeAg- and six anti-HBe-positive; two were negative for both. Of 45 36 had HBV DNA in serum. In 38 of 47 HBV DNA and in 31 of 42 HBcAg could …
Hepatic expression patterns of the large and middle hepatitis B virus surface proteins in viremic and nonviremic chronic hepatitis B.
1990
The envelope of hepatitis B virus consists of large, middle, and small hepatitis B surface proteins. Recent data from in vitro studies suggest that intracellular expression and distribution of the three polypeptides may be variable. These observations in artificial expression systems prompted this analysis of the occurrence and distribution of the three hepatitis B surface proteins in the liver tissue of substantial viremic (hepatitis B virus DNA- and hepatitis B e antigen-positive) and low-viremic or nonviremic (hepatitis B virus DNA-negative, anti-hepatitis B e antigen-positive) carriers by specific monoclonal antibodies against large, middle, and small proteins. Patients with an active f…
Assay of hepatitis B virus DNA by polymerase chain reaction and its relationship to Pre-S- and S-encoded viral surface antigens
1991
The polymerase chain reaction was evaluated as a diagnostic tool in 72 chronic hepatitis B virus carriers. Hepatitis B virus DNA was detectable in the serum of HBsAg—positive virus carriers using aliquots as small as 100 al. The detection limit for cloned hepatitis B virus DNA was 100 ag. Primer pairs for different regions of the HBV genome resulted in different sensitivity. Detection of the amplified hepatitis B virus DNA by Southern blotting and subsequent scintillation counting or densitometry allowed a semiquantitative assay. Using several primer pairs in parallel for optimal detection, all HBeAg-positive HBsAg carriers, 80% of HBe antibody—positive symptomatic HBsAg carriers and 57% of…
Ligase Chain Reaction (LCR®) assay for semi-quantitative detection of HBV DNA in mononuclear leukocytes of patients with chronic hepatitis B
1996
Summary. A ligase chain reaction (LCR®)-based approach to detect hepatitis B virus (HBV) DNA in peripheral blood mononuclear cells (PBMC) is described. Using this new amplification technique, we determined semi-quantitatively the amount of a short HBV S-gene fragment in PBMC lysates of 25 patients with different forms of chronic hepatitis (group A (n= 8), hepatitis B s antigen (HBsAg)+/hepatitis B e antigen (HBeAg)+; group B (n= 9), HBsAg+/HBeAg-; group C (n= 8), HBsAg-/HBeAg-). The LCR results were compared with the findings obtained with polymerase chain reaction (PCR) amplification of three distinct HBV gene regions (preS1/2, S and C) and related to the serological profiles of the patien…
Mutation specific PCR and direct solid phase sequencing assay for the detection of hepatitis B virus pre-C/C mutants in anti-HBe-positive, chronic he…
1994
Sequence analysis of the HBV DNA from patients with anti-HBe+, chronic hepatitis B revealed that the lack of HBeAg is mostly due to a single GA transition at nucleotide position 1896, resulting in a translational stop codon. A point mutation-specific polymerase chain reaction (msPCR) for the detection of this genetic variant was established. Two serologically defined groups of patients with symptomatic chronic hepatitis B (HBeAg+ n = 14, anti-HBe+ n = 11) were included in this study. Viral DNA from 43 sera (26 eAg+/17 anti-HBe+) was amplified twice, using two different sets of PCR primers. Each set contained the same — strand primer, but the + strand primers differed at their 3′-end, thus b…
Stop codon insertion restores the particle formation ability of hepatitis B virus core-hantavirus nucleocapsid protein fusions.
2003
In recent years, epitopes of various origin have been inserted into the core protein of hepatitis B virus (HBc), allowing the formation of chimeric HBc particles. Although the C-terminus of a C-terminally truncated HBc (HBcΔ) tolerates the insertion of extended foreign sequences, the insertion capacity is still a limiting factor for the construction of multivalent vaccines. Previously, we described a new system to generate HBcΔ mosaic particles based on a read-through mechanism in an <i>Escherichia coli</i> suppressor strain [J Gen Virol 1997;78:2049–2053]. Those mosaic particles allowed the insertion of a 114-amino acid (aa)-long segment of a Puumala hantavirus (PUUV) nucleocap…
Virus replication and virion export in X-deficient hepatitis B virus transgenic mice
2002
The function of the X protein (pX) in the replication cycle of mammalian hepadnaviruses is enigmatic. Using tissue culture experiments it has been shown that the X gene product is not central to hepatitis B virus (HBV) replication and virion export. However, at present it is still unclear whether this also applies to the in vivo situation. Using a terminally redundant X-deficient HBV DNA construct, transgenic mice were established that exhibited high-level expression of the viral core protein in liver and kidneys. Importantly, replicative DNA intermediates and mature viral genomes could be detected in the liver and serum of these mice, respectively. These findings indicate that, in the in v…