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

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

Sera from 71 patients with acute liver injury have been tested for antibodies to hepatocyte membrane lipoprotein complex (LSP) using a sensitive radioimmunoassay. Two main patterns of anti-LSP response were seen. In the first, seen in patients with type A and B viral hepatitis, anti-LSP antibodies were detectable at presentation, with the highest titres two to 10 days before the peak in serum aminotransferases and, in the hepatitis B patients, when viral DNA polymerase concentrations were still high, indicating active viral replication. These findings are consistent with the anti-LSP response being consequent on an interaction between T cells and neoantigens on the liver cell surface. A similar pattern was found in halothane hepatitis where immune responses to a halothane-altered liver membrane antigen are present early in the course of the disease. In the second type of response, exemplified by cases with paracetamol-induced hepatic necrosis, anti-LSP was only occasionally detectable at presentation, although present in very low titre later in the clinical course. This may be due to the release of altered antigen at the time of hepatocellular injury. The same pattern was found in a selected group of patients with uncomplicated acute alcoholic hepatitis, suggesting that in both these groups of patients the liver damage may have been due to a direct toxic effect on liver cells.
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PMID:Anti-LSP antibodies in acute liver disease. 708 6

The recently described protein kinase activity in hepatitis B virus core antigen particles (Albin and Robinson, J. Virol. 34:297-302, 1980) has been demonstrated here in the liver-derived core particles of ground squirrel hepatitis virus. Both protein kinase activities were initially associated with DNA polymerase-positive heavy core particles in CsCl density equilibrium gradients and shifted to polymerase-negative cores during the course of purification. The major core-associated polypeptide of each virus was the dominant species labeled. A variable number of other polypeptide species were also labeled by this reaction. Tryptic peptide mapping of both major and minor phosphorylated polypeptides of each virus resulted in similar patterns, suggesting that many of the sites of phosphorylation were the same in the components of each core particle. Hydrolysis of these phosphorylated core particles revealed a major phosphoamino acid as serine and a minor phosphoamino acid as threonine. The products of the protein kinase reaction in both human hepatitis B and ground squirrel hepatitis virus core particles, then, share many characteristics. The possible function(s) of this protein kinase activity is discussed in the light of similarly characterized activities in other animal viruses.
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PMID:Core particles of hepatitis B virus and ground squirrel hepatitis virus. II. Characterization of the protein kinase reaction associated with ground squirrel hepatitis virus and hepatitis B virus. 710 41

A DNA polymerase present in particles with a density greater than 1.20 g/cm3 and capable of using a synthetic RNA template has been sought in human malignancies. This report deals with a study of a great number of peripheral-blood samples from normal controls and patients with malignant and non-neoplastic haematological disorders. For screening purposes a simplified detection test was used. In 63 controls low levels of enzyme activity were found. The enzyme activities showed a biphasic distribution pattern. Three out of 53 patients with non-neoplastic, miscellaneous haematological disorders had an elevated enzyme level associated with active viral infections (hepatitis, mononucleosis infectiosa). In 128 patients suffering from haematological malignancies 18 out of 21 cases of elevated enzyme level were associated with the presence of more than 10% pathological cells in the white blood cell fraction.
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PMID:Particle-bound DNA polymerase activity in haematological disorders and normal controls. 713 Feb 42

Twenty-five patients with chronic type B hepatitis documented by liver biopsy were followed for 1 to 6 years with serial measurements of aminotransferase levels, hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg) and antibody (anti-HBe), and hepatitis B virus DNA polymerase. Initially, all were positive for HBsAg and HBeAg and had elevations in serum aminotransferases. In follow-up, only one lost HBsAg reactivity. In 13, however, elevated aminotransferase levels spontaneously fell to normal and have remained normal. These 13 also had a seroconversion from HBeAg to anti-HBe, and all became negative for serum DNA polymerase. Most had a fall in HBsAg titer. This seroconversion occurred concurrently with or several months before the fall in aminotransferase levels. In contrast, the 12 persons who remained HBeAg positive continued to have elevated aminotransferase levels. All 10 of these patients who were initially positive for DNA polymerase remained positive. These data suggest that many patients with chronic type B hepatitis eventually have a spontaneous remission in clinical and biochemical evidence of active disease, usually heralded or accompanied by the disappearance of HBeAg and DNA polymerase.
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PMID:Seroconversion from hepatitis B e antigen to antibody in chronic type B hepatitis. 723 15

Hepatitis-B core antigen (HBcAg) was released from Dane particles previously separated from anti-HBc by repeated pelleting through sucrose gradients separated into three HBcAg populations when analysed by cesium chloride density gradient centrifugation. Heavy HBcAg particles banded at a density of 1.355 gm/ml, intermediate HBcAg particles at a density of 1.33 gm/ml, and light mediate HBcAg particles at a density of 1.30 gm/ml. Like heavy HBcAg particles, intermediate HBcAg particles contained DNA polymerase activity, but the ratio of HBcAg to DNA polymerase activity was significantly different in both populations. Intermediate HBcAg particles could not be separated from heavy HBcAg particles by rate sedimentation centrifugation. The size of the HBV-DNA and the size of its single-stranded gaps were not significantly different in heavy and intermediate HBcAg populations. Data accumulated in this paper suggest that the intermediate HBcAg particle differs from the heavy HBcAg particle by the amount of HBcAg polypeptides and the number of HBcAg determinants exhibited.
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PMID:Demonstration and partial characterization of an intermediate HBcAG (Dane particle) population. 728 14

Sodium hypochlorite (NaOCl) was examined as an effective disinfectant in hepatitis laboratories. Concentrations of NaOCl containing 5,600 ppm (5,600 microgram/ml) of available chlorine were found to be effective in destroying the antigenicity of hepatitis B surface antigen (HBsAg) in virion-rich plasma after an exposure time of 1 min or more. In the treatment of protein-deficient solutions containing HBsAg, smaller concentrations of available chlorine (less than 500 pm) are equally effective. Neither 17-to 25-nm HBsAg particles nor 45-nm virion particles could be detected by electron microscopy after treatment. chemical interaction of protein and NaOCl was confirmed by isoelectrofocusing of 125I-labeled HBsAg. More than 90% of the labeled material was found at pH 3.0 or lower, indicating complete antigen oxidation. Labeled HBsAg was reduced in density from 1.21 g/cm3 in CsCl to approximately 1.07 g/cm3 after treatment with NaOCl. Both hepatitis B core antigen and deoxyribonucleic acid polymerase activity were significantly reduced after interaction with hypochlorite solutions. These results show that NaOCl destroys hepatitis B antigenicity and virus structures and therefore may be utilized as a disinfectant for the virus.
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PMID:Immunological and biophysical alteration of hepatitis B virus antigens by sodium hypochlorite disinfection. 731 5


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