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)

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 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

We examined the clinical significance of hepatitis Be antigenemia in 36 HBsAg positive pediatric dialysis and renal transplant patients. One hundred twenty-seven sera were tested for HBeAg and anti-HBe. Seventy-three sera (57%) from 29 patients (81%) contained HBeAg. The presence of HBeAg was associated with an increased titer of HBsAg (P < 0.005) and with the presence of the HBsAg carrier state (P < 0.001). HBeAg was found in 40% of specimens taken from dialysis patients, and in 70% of specimens from transplant patients (P < 0.001). No serum contained anti-HBe, although 28 of 29 sera (97%) tested had antibody to HBcAg. No association was found between the presence of HBeAg and serum aminoleucine transferase levels or the histologic evidence of chronic active hepatitis. Fifteen HBeAg negative sera from patients persistently positive for HBsAg were tested for HBV-specific DNA polymerase activity; 7 (47%) had significant activity. Since both HBeAg and DNA p are indicators of infectivity, many HBeAg negative sera from immunosuppressed HBsAg carriers may be infectious.
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PMID:Hepatitis B infection in pediatric dialysis and transplant patients: significance of e antigen. 699 41

Hepatitis B virus (HBV) of man has several characteristics that distinguish it from viruses of other groups. These include its ultrastructure, viral DNA size and structure, a virion DNA polymerase which repairs a single-stranded region in the viral DNA, liver tropism, character of persistent infection, and association with hepatitis and hepatocellular carcinoma. Recently three other viruses have been found in other animal species that appear to share these characteristics although the viruses are not identical. HBV, Woodchuck hepatitis virus (WHV), ground squirrel hepatitis virus (GSHV), and duck hepatitis virus (DHV) appear to be members of a new virus group that might be designated the Hepadna virus group. Genetic variation among hepatitis B viruses includes the antigenic variation in the surface antigen (HBsAg) which constitutes the known HBsAg subtypes. There is also frequent variation in DNA base sequence among HBVs isolated from different patients.
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PMID:Genetic variation among hepatitis B and related viruses. 701 20

Two patients referred for cancer chemotherapy were found to be chronic, asymptomatic hepatitis B surface antigen (HBsAg) carriers. They had normal serum aminotransferase levels, but their sera were positive for HGsAg and antibody to hepatitis B e antigen. Both patients developed acute, icteric hepatitis within 3 months of starting cycled chemotherapy. In both cases, the disease seemed to be caused by a recurrence of type B hepatitis; it was accompanied by a marked increase in HBsAg titer and the appearance of hepatitis B virus DNA and DNA polymerase in the serum. One patient had a second episode of acute hepatitis after a second course of chemotherapy, but both patients ultimately recovered and became seronegative for HBsAg. Thus, it seems that cancer chemotherapeutic agents can reactivate type B hepatitis in asymptomatic HBsAg carriers. This reactivation is most likely due to an increase in hepatitis B virus synthesis followed by a rebound in host immune responses to hepatitis B virus infection when therapy is stopped. Such a phenomenon could have important implications for the therapy of chronic hepatitis B virus infection.
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PMID:Reactivation of chronic hepatitis B virus infection by cancer chemotherapy. 706 60

Solid-phase radioimmunoassays for woodchuck hepatitis virus (WHV) surface antigen (WHsAg) and antibody to it (anti-WHs) were developed. The test for WHsAg could detect as little as 10 ng/ml. In both tests it was necessary to employ radiolabeled WHsAg instead of anti-WHs as the probe because the latter appeared to be labile to the conditions of labeling. The tests were used to characterize naturally acquired and experimental WHV infections of woodchucks. Forty-three of 72 wild-caught woodchucks had serological evidence of WHV infections; 16 of these resulted in chronic infection, and the remainder were self-limiting. All chronically infected animals were positive for WHsAg and DNA polymerase activity. During 3 years of observation, 11 of the 16 WHsAg-positive animals and 3 of the 27 anti-WHs-positive animals, but none of the 21 uninfected animals developed hepatocellular carcinoma. Seroconversion, possibly resulting from infection with WHV, was documented in a chimpanzee inoculated with WHV. An immune adherence hemagglutination test for WHsAg was also developed by using anti-WHs of chimpanzee origin as a reagent, but the test was not useful for detecting anti-WHs of woodchuck origin because of the lability of the latter.
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PMID:Natural and experimental infection of woodchucks with woodchuck hepatitis virus, as measured by new, specific assays for woodchuck surface antigen and antibody. 707 21


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