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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In 1974, Prince et al. reported the existence of posttransfusion hepatitis with a long incubation period which was not related to hepatitis B virus (HBV). These cases were named "non-A, non-B" (NANB) hepatitis. The genome of NANB hepatitis virus was discovered recently using a recombinant complementary DNA (cDNA) approach. It was termed the hepatitis C virus (HCV), and a specific diagnostic tool for the circulating HCV antibody (anti-HCV) was developed using a purified viral polypeptide derived from recombinant yeast expressing a small part of the HCV genome. HCV is believed to be the main cause of blood-borne non-A, non-B hepatitis worldwide, which frequently evolves to chronic hepatitis and cirrhosis, and which may also be involved in the development of hepatocellular carcinoma. HCV is classified as part of the flaviviridae family and contains a positive-stranded RNA molecule by approximately 10 kb nucleotides. The HCV genome encodes a large polyprotein precursor, which is processed in structural nucleocapsid and envelope proteins and in non-structural proteins (NS1-NS5). Nucleotide sequence comparisons of distinct HCV isolates have shown a significant genetic variability between the different HCV strains. At present the diagnosis of HCV infection depends on various anti-HCV tests including second generation HCV Ab. Antigenic markers for HCV are being developed but the concentrations of HCV antigens in serum are at the lower limit of detectability by existing immunoassay technology. A polymerase chain reaction has been used to detect HCV RNA in the serum and liver. Serum HCV RNA disappears from serum after effective IFN treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Fundamental studies of hepatitis C virus: a review]. 133 74

Seroconversion from eAg to anti-e is frequently seen in the course of chronic hepatitis B infection. This phenomenon is closely related to mutation of the precore region; a G-to-A substitution of nucleotide position 1986 replaces tryptophan to translational stop codon. This mutant is responsible for the fulminant hepatitis or acute exacerbation of chronic hepatitis B. The hepatitis C virus shows a high rate of genome variations, especially at the envelope (E and NS1) region, where a neutralizing epitope is believed to exist. According to the sequence identity, the hepatitis C virus is divided into four subtypes. The virus appears to evolve separately in geographically different areas and the subtyping may have some clinical implications, such as in interferon treatment. Hepatitis E virus has three open reading frames and share the high nucleotide identity among strains isolated from Myanmar and China. Hepatitis E is endemic in the developing world and is not present in industrialized countries.
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PMID:[Current status in hepatitis virus research]. 133 64

A cDNA fragment encompassing the 5'-terminal half of the NS1 region of the hepatitis C virus (HCV) genome was cloned. The cDNA was expressed in insect cells using a recombinant baculovirus, and a protein band of approximately 21K was identified by immunoblotting with a serum sample from a patient with chronic hepatitis C. Antibody to the protein was detected in sera from 13.4% of patients with chronic non-A, non-B hepatitis (NANBH), 20.8% of patients with liver cirrhosis and 16.8% of patients with hepatocellular carcinoma with no serum markers for hepatitis B virus infection. However, the antibody was not detected in sera from patients with acute NANBH. The prevalence of antibody to the protein encoded by the NS1 region was lower than that of antibody to the HCV core protein, but much higher than that of antibody to the envelope protein. Thus, the NS1 region of the HCV genome is suggested to encode a protein produced during the course of HCV replication.
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PMID:Expression of the amino-terminal half of the NS1 region of the hepatitis C virus genome and detection of an antibody to the expressed protein in patients with liver diseases. 137 27

To investigate the genomic characterization of hepatitis C virus (HCV) isolated from patient who contracted hepatitis during an epidemic of non-A, non-B (NANB) hepatitis in Shimizu city, Japan, we have cloned the nucleotide sequence of the viral genome (HCV-KF) spanning the structural domain. When compared to other previously reported HCV isolates, HCV-KF showed an overall identity at the amino acid level of 90.0 to 92.1% with Japanese isolates and 80.9 to 82.1% with American-like isolates. The HCV-KF genome displays an insertion of three nucleotides in-frame (corresponding to one amino acid) found at the junction between the E1 and E2/NS1 region. The mutation rate of the HCV-KF genome was assessed by comparing the nucleotide and deduced amino acid sequences of the viral RNA obtained from the serum of the original patient with viral sequences derived from the serum of a chimpanzee inoculated with the same serum 9 years previously. The substitution rate of the viral genome was estimated at 0.9 x 10(-3) nucleotides per site per year for the HCV structural region. The highest mutation rate was found in the hypervariable region within the E2/NS1 domain. It is suggested that the outbreak in Shimizu city was caused by a strain of HCV closely related to the Japanese-like subgroup of isolates.
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PMID:Genomic characterization and mutation rate of hepatitis C virus isolated from a patient who contracted hepatitis during an epidemic of non-A, non-B hepatitis in Japan. 138

cDNA fragments encoding the putative structural genes of the hepatitis C genome were isolated from a plasma pool of Japanese non-A, non-B hepatitis patients and from sera of individual Spanish patients. From the Japanese plasma pool a series of E1 clones was obtained that showed 88-98% homology among each other, both at the nucleotide and amino acid level. Compared to the sequences published by the Chiron Corporation and Takeuchi et al., the amino acid homology was 75-79% and 91-94%, respectively. Analysis of the core and E2/NS1 genes showed a high conservation of the core sequence and a high sequence variation in the 5' end of the E2/NS1 gene. The E1 gene of one Spanish isolate showed greater homology to the Chiron than to the Japanese sequence. Another Spanish isolate was more homologous to the Japanese sequence indicating that both hepatitis C genotypes are present in Europe. Analysis of the E1 gene of an isolate derived from a single patient with a 5-year interval revealed nine nucleotide and five amino acid changes.
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PMID:Sequence analysis of the putative structural genes of hepatitis C virus from Japanese and European origin. 166 28

The sera of 36 French patients with post-transfusional and sporadic non-A, non-B (NANB) chronic hepatitis were investigated, with a combination of serological and polymerase chain reaction (PCR) assays, for HBV and HCV infections. Eighty-nine percent of the patients were found positive with serological and/or molecular tests. Among the positive patients, 68% (22/32) were found positive for both anti-HCV and HCV-RNA, 16% (5/32) and 16% (5/32) were found positive only for anti-HCV or HCV-RNA, respectively. HBV-DNA sequences were detected in two patients associated to the HCV viraemia. This study confirms the extremely high prevalence of HCV infection in NANB chronic hepatitis in France. It also shows the possible co-infection by HCV and HBV in NANB hepatitis. We have also determined the nucleotide sequence of the 5' non-coding, E1, E2/NS1 and NS3/NS4 regions of a French isolate using the polymerase chain reaction. Comparison of these nucleotide sequences with those available from American and Japanese isolates showed a significant genetic variability. The genetic variability is higher in the E2/NS1 (13 to 33% and 12 to 30% at the nucleic acid and amino acid level, respectively) than in the E1 (10 to 28% and 7 to 21%) and NS3/NS4 (5 to 21% and 2 to 7%) regions. The sequence of the French isolate is more closely related to that of the American HCV prototype than to the Japanese HCV isolates. This study confirms the extent of HCV genetic variability.
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PMID:Hepatitis C virus (HCV)-RNA in non-A, non-B chronic hepatitis in France. Nucleotide sequence of a French HCV isolate. 166 29

Immunization of monkeys with yellow fever virus-specified nonstructural protein NS1 resulted in protection against fatal hepatitis as well as marked reduction in the magnitude of viremia after subcutaneous challenge with yellow fever virus. The results may be relevant to the design of possible subunit or recombinant flavivirus vaccines.
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PMID:Protection against yellow fever in monkeys by immunization with yellow fever virus nonstructural protein NS1. 378 16

Hepatitis C virus (HCV) infection is characterized by persistence of liver inflammation that often leads to end-stage liver disease, although the mechanisms are not fully understood. A hypervariable region (HVR) has been reported in the E2/NS1 region of the HCV genome, in which striking diversity is found among different HCV isolates. To investigate the association of the HVR alterations with the clinical courses of HCV infection, a longitudinal analysis of the HVR in patients with acute HCV infection was carried out. Plasma samples were obtained at several times in three patients with acute hepatitis C. Plasma RNA was extracted and reverse transcribed, and DNA fragments that included the HVR were amplified by PCR. The sequences of the HVR were directly determined from the PCR products by the dideoxy chain termination method, from which amino acid sequences were deduced. In all cases, plasma HCV-RNA disappeared with the improvement of the initial alanine aminotransferase (ALT) elevation, but HCV-RNA reappeared about 1 year later with or without deterioration of the hepatitis. In a case of sporadic acute hepatitis, the HCV in the recurrent phase had seven amino acid substitutions in the HVR compared with that in the acute phase, although no amino acid changes were noted during the initial acute phase. In a case of posttransfusion hepatitis, a marked difference was observed between the acute and the recurrent phases, with an amino acid homology of 30% (8/27). The mutation rate of the HVR had a tendency to accelerate as the HCV infection progressed to the chronic stage.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Sequential change of the hypervariable region of the hepatitis C virus genome in acute infection. 750 88

The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis.
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PMID:Detection of the putative E2 protein of hepatitis C virus in human liver. 751 51

Hepatitis C virus (HCV) infections in a cohort of chimpanzees were studied retrospectively. All animals had been inoculated intravenously with materials derived from a single-source chimpanzee plasma implicated in non-A, non-B hepatitis, prepared by extensive ultracentrifugation. Anti-HCV and HCV RNA were monitored by the confirmatory line immunoassay and by an RNA-capture polymerase chain reaction method, respectively. In a chronically infected chimpanzee, HCV RNA was detectable after 32 days and throughout the acute phase, dropped transiently below detection level, and became detectable again. In 3 other chimpanzees with acute resolving infections, HCV RNA was detected 7-11 days after inoculation and became permanently undetectable after alanine aminotransferase normalization. Various anti-HCV profiles were detected among the chimpanzees. Analysis of the hypervariable region in E2/NS1 in 7 chimpanzees suggested genome stability on transmission, revealed different mutation frequencies during chronic infection, and suggested the importance of immune selection during chronic HCV infection.
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PMID:Longitudinal analysis of hepatitis C virus infection and genetic drift of the hypervariable region. 754 28


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