Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Abrupt increases of alanine transaminase were observed in 6 of 23 non-treated, male homosexuals with chronic hepatitis associated with hepatitis B virus. Before this occurrence, all subjects had hepatitis B e antigen (HBeAg) and elevated DNA polymerase activity. Within 3 months, HBeAg was nondetectable in 3 subjects and elevated DNA polymerase disappeared in 4. These serologic events were not always sustained, however. In 3 subjects, reactivation of hepatitis B virus infection occurred within the subsequent 6-month period. Serologic testing for cytomegalovirus, Epstein-Barr virus, delta agent, and hepatitis B surface antigen (HBsAg) subtype showed that episodes of clearance and reactivation were not explainable by secondary infection with these agents or infection with a different HBsAg subtype. Spontaneous clearance and reactivation of hepatitis B virus infection may commonly occur among male homosexuals with chronic type B hepatitis. These phenomena should be considered when evaluating the need for treatment or interpreting the results of investigations that use anti-viral therapy.
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PMID:Spontaneous clearance and reactivation of hepatitis B virus infection among male homosexuals with chronic type B hepatitis. 669 58

The entity of chronic hepatitis has long been an enigma, and its treatment confusing. Recent studies have indicated the importance of excluding causes such as drugs, Wilson's disease and alpha 1-antitrypsin deficiency. After excluding such causes, there are 3 major groups--'autoimmune', hepatitis B, and non-A, non-B (NANB) in all of which an immunological basis for pathogenesis exists. The autoimmune group has been subdivided into a milder type (chronic persistent hepatitis) and a more severe type (chronic active hepatitis) on histological grounds. Corticosteroids are indicated in chronic active hepatitis if cirrhosis or bridging necrosis is present. However, corticosteroids are contraindicated in disease due to the hepatitis B virus where chronic active hepatitis correlates with the presence of replicating virus (serum positive for e antigen, DNA polymerase and HBV-DNA), and in such cases antiviral agents and immunomodulation are being studied. Very little is known about NANB hepatitis in the absence of an assay and there may be more than a single agent. In hepatitis B, the development of serological markers, molecular probes (HBV-DNA), natural animal hepatitis with near-identical viruses, and delta antigen (a virus requiring co-infection with hepatitis B) have all extended our knowledge so dramatically that it is hoped that the enigma of chronic hepatitis will be solved when an assay for NANB hepatitis becomes available.
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PMID:Chronic hepatitis. Aetiology and current management. 673 69

Human hepatitis B-like viruses have been found in several animal species, including Chinese ducks. Sera from Chinese carrier ducks which were positive for duck hepatitis B virus (DHBV) were inoculated in 33 Japanese one-day-old ducklings. The same sera were inoculated in four 3-week-old ducklings, and three 3-month-old ducks. Ten uninoculated ducklings served as controls. Hepatitis B e-antigen positive human sera and DNA polymerase-positive woodchuck sera were also inoculated into ducklings. DHBV was demonstrated in serum of all ducklings inoculated at one day of age and persisted for more than 6 months in 17 of 20 ducks. In the three ducks in which viremia disappeared, viral DNA was found in liver tissue. Southern hybridization revealed only free viral DNA in infected ducks. Only 1 of 7 ducklings inoculated at 3 weeks or later developed persistent infection. No cross-infectivity by hepatitis B virus or by woodchuck hepatitis virus was demonstrated. By inoculating DHBV-positive sera into 1-day-old ducklings of a virus-free Japanese flock, we were able to transmit DHBV in all of them and established a chronic carrier state in all ducks which were inoculated at 1 day of age.
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PMID:Transmission of duck hepatitis B virus from Chinese carrier ducks to Japanese ducklings: a study of viral DNA in serum and tissue. 674 48

To examine the period between disappearance of hepatitis B e antigen (HBeAg) and appearance of anti-HBe, 48 patients with clinicopathologically verified chronic B hepatitis were followed every 1 to 3 months after HBeAg clearance. Sera were tested by radioimmunoassay for HBeAg and anti-HBe. Anti-HBe appeared in days to years, mostly (78.7%) within 1 year, after disappearance of HBeAg. Only 40.5% of patients had an "e-window" shorter than 1 month. Clinical and histological exacerbation preceding HBeAg clearance precipitated or accelerated appearance of anti-HBe. Since the patients in the "e-window" period were positive for DNA polymerase, it is suggested that the "e-window" reflects relative insensitivity of the radioimmunoassay rather than absence of HBeAg/anti-HBe. Therefore, HBeAg can reappear and clinical activity can relapse particularly during immunosuppressive therapy.
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PMID:The window period between hepatitis B e antigen and antibody in chronic type hepatitis. 674 49

Sera of patients with past or ongoing hepatitis -B virus infection were tested for the presence of inhibitors of hepatitis -B virus-specific deoxyribonucleic acid (DNA) polymerase activity. None of the sera tested, which included those from anti-hepatitis B surface- and anti-hepatitis B core antigen-positive hemophiliacs, anti-hepatitis Bc antigen-positive hepatitis B surface antigen carriers, patients with hepatitis B surface antigen-positive chronic active hepatitis, hepatitis B surface antigen-positive hemodialysis patients, tumor patients with minimal hepatitis, patients with acute type B, type A, and type non-A, non-B hepatitis and individuals with autoimmune phenomena, contained inhibitors of DNA polymerase activity. This implies that the DNA polymerase test is not affected when utilized to quantitate DNA-containing Dane particles. In addition, there is no evidence that inhibitors of DNA polymerase activity play some pathogenic role in the course of hepatitis B virus infection.
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PMID:Failure to detect naturally occurring serum inhibitors of hepatitis B virus deoxyribonucleic acid polymerase. 676 9

Hepatitis B virus-like particles including: small spheres and filaments 15--25 nm in diameter together with a 35--40 nm Dane particle-like virion have been identified in sera of patients with non-A, non-B hepatitis. In a coded serological study, such particles were detected transiently in 3/4 acute, and persistently in 7/8 chronic cases of non-A, non-B hepatitis with non-A, non-B antigenemia. Only 2/12 similar cases without non-A, non-B antigens (Ag) in serum had detectable particles but neither patients with drugs, or type A hepatitis, nor cases of obstructive jaundice. The particles did not express hepatitis B surface (HBs) or non-A, non-B Ag at their surface but were associated, in three patients, with significant endogenous DNA polymerase activity. Furthermore, particles similar to hepatitis B cores (BHc) and also associated with DNA polymerase activity were demonstrated by sucrose gradient ultracentrifugation of a liver homogenate obtained from a patient who had died of non-A, non-B hepatitis. The non-A, non-B hepatitis virion described here appears, therefore, as a hepatitis B-like virus. The exact kinship between these two agents is currently being investigated.
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PMID:Non-a, non-b hepatitis: identification of hepatitis-B-like virus particles in serum and liver. 677 42

Using immunodiffusion, a major cross-reactivity had been previously demonstrated between hepatitis B(HBe/3 Ag) and the antigen reported in the serum on non A, non-B hepatitis patients, therefore redesignated NANBe Ag. By direct immunofluorescence a new antigen associated with, but distinct from, NANBe Ag has now been identified in the liver of 14/26 patients with NANB chronic active hepatitis. The homologous antibody was detected in the serum of these 14 patients. Behaving like HBc Ag and cross reacting with it by immunofluorescence, the new antigen was termed NANBc Ag. Anti NANBc also became detectable in serial acute phase and convalescence sera from 5/5 NANB Ag-positive posttransfusion hepatitis cases. Further characterization of NANBe and NANBc antigens achieved by fractionation of a NANB virus-infected liver showed NANBc Ag to be expressed on 22-25 nm HB core-like particles containing DNA polymerase activity. Cross-reactivity between NANBc and HBc antigens was confirmed by immunodiffusion. Liver-derived NANBe Ag identical to serum NANBe Ag exhibited the same physical properties as HBe/3 Ag and could be similarly released by disruption of the non-A, non-B, virus cores. These results indicate that hepatitis B and NANB virions not only share the same structure and DNA polymerase activity but are also antigenically related and belong to the same new class of DNA viruses.
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PMID:Non-A, Non-B hepatitis virus: identification of a core antigen-antibody system that cross reacts with hepatitis B core antigen and antibody. 679 10

We have studied the effect of short-term high-dose prednisone therapy on aminotransferase levels and hepatitis B virus markers in 6 patients with chronic type B hepatitis. All showed a decrease in amino transferase levels during treatment. This was followed by a transient increase in aminotransferase levels after prednisone was discontinued. In 5 patients, there was a decrease in hepatitis B virus deoxyribonucleic acid polymerase activity at the time of postprednisone peak of aminotransferase levels. Three of them became transiently deoxyribonucleic acid polymerase negative. All the patients have remained hepatitis B e antigen-positive throughout the period of observation. We have also found transient deoxyribonucleic acid polymerase negativity unrelated to prednisone therapy in 2 patients with chronic type B hepatitis: in one during a superimposed episode of acute type A hepatitis, and in the other during a period of pronounced alanine aminotransferase elevation. We postulate that these periods of deoxyribonucleic acid polymerase negativity are due to a decreased number of hepatitis B virus-infected cells in the liver as a consequence of hepatic necrosis.
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PMID:Effect of short-term prednisone therapy on aminotransferase levels and hepatitis B virus markers in chronic type B hepatitis. 683 70

We have studied three patients with chronic HBV infection who had a superimposed bout of type A hepatitis. The patients recovered uneventfully without observing a change in their clinical course afterwards. In one patient we observed transient disappearance of DNA polymerase during type A hepatitis; we have postulated that this is probably related to hepatic necrosis.
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PMID:Acute type A hepatitis in three patients with chronic HBV infection. 687

A virus given the name ground squirrel hepatitis virus (or GSHV), with many of the unique characteristics of human hepatitis B virus (HBV), has been found in Beechey ground squirrels in northern California. Common features include virus morphology, viral DNA size and structure, a virion DNA polymerase that repairs a single-stranded region in the viral DNA, crossreacting viral antigens, and persistent infection with viral antigen continuously in the blood. Although similar, GSHV and HBV Are not identical. The ground squirrel virion has a slightly greater diameter, the viral surface antigens crossreact only partially and, thus, are not identical, and GSHV DNA has two restriction endonuclease EcoRI cleavage sites in contrast to the single site in HBV DNA. Thus, GSHV is a member of the virus group that includes HBV and the virus recently found in woodchucks in the eastern United States and named woodchuck hepatitis virus. It is not yet known how closely the ground squirrel and woodchuck viruses are related.
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PMID:A virus in Beechey ground squirrels that is related to hepatitis B virus of humans. 693 Jun 77


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