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)

Four strains of the coronavirus murine hepatitis virus were examined for the presence of phosphorylated proteins. The nucleocapsid protein was determined to contain phosphate covalently linked to serine but not to threonine residues. The nucleocapsid protein was the only phosphorylated protein detected in these strains of murine hepatitis virus.
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PMID:Phosphoproteins of murine hepatitis viruses. 22 84

Lymphocytic dipeptidylpeptidase IV (DPP-IV, E.C. 3.4.14.5) is described as a marker enzyme of immunostimulant T-lymphocytes as well as functional characteristic of interleukin-2-producing cells. Cytochemical staining of DPP-IV positive lymphocytes and measurements of DPP-IV activity in mononuclear cells and in sera of patients suffering from different kinds of liver diseases were performed to evaluate the average activities in positive cells. The results demonstrated that this serine exopeptidase exhibits extremely low activity in autoimmune chronic hepatopathies. On the contrary, hepatitis-B-associated liver diseases were connected with markedly increased values. Furthermore, significant differences of DPP-IV activity were found in different kinds of acute and chronic liver diseases. These findings are discussed in connection with the participation of dipeptidylpeptidase IV in impaired immunoregulation of the altered liver.
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PMID:Changes of dipeptidylpeptidase IV as a membrane marker of lymphocytes in acute and chronic liver diseases--biochemical and cytochemical investigations. 168 96

The effect of tumor necrosis factor (TNF)-alpha and interleukin-1 (IL-1) alpha, which are thought to be principal mediators inducing homeostatic abnormalities during endotoxemia, were investigated on cultured hepatocytes in an attempt to understand their role in the pathogenesis of fulminant hepatitis. Both TNF and IL-1 had no direct cytotoxicity on cultured adult rat hepatocytes as assessed by their effects on protein synthesis and also cytosolic enzyme activity released into the culture medium in the presence of 5 mM D-galactosamine (Ga1N). However, IL-1 caused a dose-dependent inhibition of DNA synthesis in cultured adult rat hepatocytes. Moreover, the serum from TNF-treated rats, prepared after intravenous administration of TNF (5 X 10(4) U per rat), caused a significant increase of enzyme release into culture medium in contrast to control rat serum. The cytotoxicity disappeared when the serum from TNF-treated rats was pretreated by heating at 56 degrees C for 30 min, and was decreased by the addition of the protease inhibitor, aprotinin. In vivo, gabexate mesilate, a serine-type protease inhibitor, prevented GalN/TNF-induced fulminant hepatitis, whereas MX-1, an anti-complement agent, had no such effect. These results strongly suggest that IL-1 has a inhibitory effect on hepatocytes in terms of DNA synthesis and that TNF indirectly induces hepatocellular damage through the serine proteases which are possibly activated by the cytokine in vivo.
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PMID:Significance of tumor necrosis factor (TNF) and interleukin-1 (IL-1) in the pathogenesis of fulminant hepatitis: possible involvement of serine protease in TNF-mediated liver injury. 191 53

The mechanism of lysis by in vivo-induced cytotoxic T lymphocytes (CTL) was examined with virus-specific CTL from mice infected with lymphocytic choriomeningitis virus (LCMV). LCMV-induced T cells were shown to have greater than 10 times the serine esterase activity of T cells from normal mice, and high levels of serine esterase were located in the LCMV-induced CD8+ cell population. Serine esterase was also induced in purified T-cell preparations isolated from mice infected with other viruses (mouse hepatitis, Pichinde, and vaccinia). In contrast, the interferon inducer poly(I.C) only marginally enhanced serine esterase in T cells. Serine esterase activity was released from the LCMV-induced T cells upon incubation with syngeneic but not allogeneic LCMV-infected target cells. Both cytotoxicity and the release of serine esterase were calcium dependent. Serine esterase released from disrupted LCMV-induced T cells was in the form of the fast-sedimenting particles, suggesting its inclusion in granules. Competitive substrates for serine esterase blocked killing by LCMV-specific CTL, but serine esterase-containing granules isolated from LCMV-induced CTL, in contrast to granules isolated from a rat natural killer cell tumor line, did not display detectable hemolytic activity. Fragmentation of target cell DNA was observed during the lytic process mediated by LCMV-specific CTL, and the release of the DNA label [125I]iododeoxyuridine from target cells and the accompanying fragmentation of DNA also were calcium dependent. These data support the hypothesis that the mechanism of killing by in vivo-induced T cells involves a calcium-dependent secretion of serine esterase-containing granules and a target cell death by a process involving nuclear degradation and DNA fragmentation.
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PMID:Mechanism of killing by virus-induced cytotoxic T lymphocytes elicited in vivo. 211 90

The genetic origin, structure, and biochemical properties of the delta antigen (HDAg) of a human hepatitis delta virus (HDV) were investigated. A cDNA fragment containing the open reading frame encoding the HDAg was transcribed into RNA and used for in vitro translation in rabbit reticulocyte lysates. The HDAg open reading frame was also inserted into an expression vector containing a simian virus 40 T-antigen promoter and expressed into COS 7 cells. In both systems, a protein species of 26 kilodaltons was synthesized from this open reading frame and could be specifically immunoprecipitated with antisera obtained from patients with delta hepatitis. A similar protein was also synthesized from antigenomic-sense monomeric HDV RNA in both systems, although the efficiency of translation was lower than that of the isolated open reading frame. This protein was found to be phosphorylated at the serine residues. Immunoperoxidase studies with anti-HDV sera demonstrated that the HDAg was expressed mainly in the nuclei of the transfected COS 7 cells. Moreover, the HDAg was shown to bind the genomic RNA of HDV. These studies indicate that HDAg is encoded by the antigenomic-sense RNA of HDV and is a nuclear phosphoprotein associated with an RNA-binding activity.
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PMID:Human hepatitis delta antigen is a nuclear phosphoprotein with RNA-binding activity. 337 72

By means of a radioimmunoassay, which utilized [125I]-epiglycanin and anti-epiglycanin antiserum induced in rabbits by injections of viable TA3-Ha ascites cells with Freund's complete adjuvant, picogram quantities of epiglycanin could be detected. Anti-epiglycanin antiserum was similarly produced in allogeneic mice. Unlabeled epiglycanin lost the capacity to compete with [125I]epiglycanin in the radioimmunoassay as a result of periodate oxidation or incubation with endo-alpha-N-acetyl-D-galactosaminidase (Diplococcus pneumoniae), an enzyme found to cleave only the disaccharide beta-D-galactopyranosyl-(1----3)-2-acetamido-2-deoxy-D-galactose chain from serine or threonine residues in epiglycanin. Glycosylhydrolases known to cleave alpha-D-mannose, beta-D-galactose (1,4-linked), beta-N-acetyl-D-glucosamine, and alpha-N-acetyl-D-galactosamine did not reduce the activity of epiglycanin. Neuraminidase enhanced the activity twofold to fivefold. The finding that little or no activity was demonstrated by the disaccharide, the reduced disaccharide, or other glycoproteins containing the same disaccharide chain suggested that the antigenic determinant probably involved the disaccharide and a unique amino acid sequence at the site of its attachment. By means of the radioimmunoassay epiglycanin cross-reactive antigens were detected in the peritoneal or pleural fluid and in the sera of patients with metastatic cancer. Lower concentrations of epiglycanin-like antigen(s) were found in the peritoneal fluid of patients with hepatitis or liver cirrhosis but not in normal serum.
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PMID:Antibody to epiglycanin and radioimmunoassay to detect epiglycanin-related glycoproteins in body fluids of cancer patients. 620 3

A DNA copy of the mRNA that encodes the nucleocapsid protein of Mouse Hepatitis Virus JHM has been cloned into pAT153. The DNA copy specifically inhibited the synthesis in vitro of the nucleocapsid protein. The cDNA was subcloned into M13 vectors and the entire sequence, 1767 bases including a 15 base terminal poly (A) tract, has been determined by chain-terminator sequencing. The sequence contained an open-reading frame that could encode a basic protein of mol.wt. 49700. From the predicted sequence it was apparent that the nucleocapsid protein has 5 basic regions, two of which are located near the middle of the sequence, a serine-rich region was also located, a feature which may be of functional importance as the nucleocapsid protein is phosphorylated at serine residues. The carboxy terminus of the nucleocapsid protein was found to be acidic. The 5' non-coding sequence contained a triple repeat of the pentamer AATCT, a structural feature which may play a significant role during the production of subgenomic viral mRNAs.
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PMID:Coronavirus JHM: nucleotide sequence of the mRNA that encodes nucleocapsid protein. 630 69

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 10 year old boy, in grade IV hepatic coma, was treated by combination of XAD-4 resin hemoperfusion (HP), activated charcoal HP (Adsorba 300C, Gambro), exchange transfusion by up to 12.0 liters of fresh whole blood, and regular dialysis. Serum free amino acids' values were consecutively assessed during 4 days of treatment. The liver was 490 gr in weight at autopsy and histologic examination revealed cellular necrosis compatible with fulminant hepatitis. Pre-treatment values of alanine, lysine, proline, phenylalanine, arginine, threonine, tyrosine and methionine were increased by 2 to 38 times of normal control, while those of cystine, glutamic acid, serine and glycine were minimally increased up to 1.7 times. Histidine, isoleucine, leucine and valine, on the other hand, were decreased by 20 to 30% and aspartic acid was the lowest at 14% of normal control. The effect of XAD-4 resin HP and exchange transfusion was rather non-specific by decreasing the total amount of amino acids. The molar ratios of branched chain amino acids vs. aromatic amino acids or essential amino were elevated by activated charcoal HP, but, did not reach to normal range.
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PMID:[Variation of serum free amino acids in fulminant hepatitis treated with hepatic assists (author's transl)]. 740 29

Targeted RNA recombination was used to construct mouse hepatitis virus (MHV) mutants containing chimeric nucleocapsid (N) protein genes in which segments of the bovine coronavirus N gene were substituted in place of their corresponding MHV sequences. This defined portions of the two N proteins that, despite evolutionary divergence, have remained functionally equivalent. These regions included most of the centrally located RNA-binding domain and two putative spacers that link the three domains of the N protein. By contrast, the amino terminus of N, the acidic carboxy-terminal domain, and a serine- and arginine-rich segment of the central domain could not be transferred from bovine coronavirus to MHV, presumably because these parts of the molecule participate in protein-protein interactions that are specific for each virus (or, possibly, each host). Our results demonstrate that targeted recombination can be used to make extensive substitutions in the coronavirus genome and can generate recombinants that could not otherwise be made between two viruses separated by a species barrier. The implications of these findings for N protein structure and function as well as for coronavirus RNA recombination are discussed.
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PMID:Construction of murine coronavirus mutants containing interspecies chimeric nucleocapsid proteins. 763 93


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