Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The C-terminal region of hepatitis B virus (HBV) e antigen (HBeAg), amino acids (aa) 121 to 147, was characterized for reactivity with 15 monoclonal antibodies (MAbs) and sera from 16 chronic carriers on the HB surface antigen with anti-HBe. Recombinant proteins exposing fragments of the HBc/e polypeptide (aa 29 to 176, 60 to 176, 101 to 176, 121 to 176, 134 to 176, 138 to 176, 139 to 176, 140 to 176, 146 to 176 and 156 to 176) fused to the N terminus of the coat protein of RNA phage fr were constructed, as were two sets of synthetic peptides covering residues 121 to 136 and 130 to 147, where each residue was sequentially substituted by alanine. The MAbs were found to recognize overlapping epitopes in the fusion proteins within residues 121 to 176; however, none of the MAbs reacted with proteins covering residues 146 to 176 and 156 to 176. Using the synthetic peptides it was found that the MAbs recognized epitopes at residues 128-TPPAYR-133, 133-RPPNAP-138, 135-PNAPIL-140, 138-PILSTLPE-145 and 143-LPET-146. Only MAbs recognizing the epitope 128-TPPAYR-133 were found to react with both native HBeAg and denatured HBcAG, whereas MAbs recognizing epitopes located closer to the C terminus of HBeAg were reactive only with denatured HBcAg. The recognition sites for the human IgG1 overlapped with the epitopes of the MAbs recognizing native HBeAg. Our interpretation of these findings is that the region 124 to 133 is on the surface of native HBeAg and denatured HBcAg, and that the adjacent region 135 to 147 is not accessible on the surface of native HBeAg, but becomes exposed on denatured HBcAg.
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PMID:Immunochemical structure of the carboxy-terminal part of hepatitis B e antigen: identification of internal and surface-exposed sequences. 768 49

Twenty-one patients with primary immunoglobulin deficiency were enrolled in a crossover study to test the efficacy and safety of Alphaglobin in comparison with the licensed preparations Sandoglobulin and Gamimune. There was no statistical difference in these parameters between Alphaglobin and Sandoglobulin/Gamimune. The level of total serum IgG and specific IgG to pneumococcal polysaccharides was similar in individual patients when they were receiving Alphaglobin or one of the other products. Transient increases in serum alanine transferase occurred in five patients on Sandoglobulin/Gamimune and two patients on Alphaglobin. Some patients showed a rise in total serum IgM afterwards, indicating a response to infection. However, serum hepatitis C virus (HCV) RNA was not found during the alanine transferase (ALT) rises, and IgM antibody to hepatitis A virus (HAV) was negative afterwards. We conclude that Alphaglobin is a safe, well tolerated and clinically efficacious treatment for patients with primary antibody deficiency.
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PMID:A prospective controlled crossover trial of a new heat-treated intravenous immunoglobulin. 781

Hepatitis B virus core protein (antigen) is an important serologic marker of hepatitis B virus infection. This protein is found in the cytoplasm or the nuclei, or both, of infected hepatocytes. A nuclear localization signal has previously been identified in the core protein sequence. This signal overlaps three repeated SPRRR motifs. In this report, we demonstrate that substitution of all of the serine residues in these three SPRRR motifs with alanine can prevent almost entirely the phosphorylation of the core protein in Huh-7 hepatoma cells, enhance nuclear localization of the core protein in both Huh-7 and nonhepatic cells, and abolish cell cycle regulation of nuclear localization of the core protein. Since the three core protein mutants which retained only one serine residue of each of the three SPRRR motifs could be phosphorylated to similar degrees, these three serine residues likely could serve as the acceptor sites for phosphorylation with equal efficiency. These results, together with the observation that the three SPRRR motifs overlap the nuclear localization signal of the core protein, raise the possibility that nuclear localization of the core protein is negatively regulated by phosphorylation of the serine residues in the SPRRR motifs.
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PMID:Phosphorylation and nuclear localization of the hepatitis B virus core protein: significance of serine in the three repeated SPRRR motifs. 781 79

We previously demonstrated that the core protein of hepatitis C virus (HCV) can suppress gene expression and replication of hepatitis B virus (HBV) in a human hepatoma cell line (HuH-7). In this study, we have characterized the phosphorylation property of HCV core protein and examined the effect of phosphorylation on its suppressive activity of HBV. Our results indicated that both the full-length HCV core protein (22 kDa) and its processed or degraded forms (14 to 18 kDa) were phosphorylated in insect cells. As demonstrated by using the glutathione S-transferase fusion protein expression system and in vitro transcription and translation system, the phosphorylation of HCV core protein was carried out by protein kinase A (PKA) and protein kinase C (PKC) in vitro. In both kinase reactions, it was determined that the phosphorylated amino acid was a serine residue. The potential phosphorylated sites in core protein were identified as residues Ser-53 and Ser-116 for PKA and Ser-53 and Ser-99 for PKC. Comparison of the phosphorylation intensities of the wild type and Ser mutants suggested that Ser-99 and Ser-116 were the major phosphorylation sites for PKC and PKA, respectively. The phosphorylation of Ser-99 and Ser-116, but not Ser-53, in HCV core protein was essential for the suppressive activity of HCV core protein on HBV gene expression and replication in HuH-7 cells. Mutation of the former two serine residues to alanine or aspartate residues led to a drastic loss of the inhibitory effects of HCV core protein on HBV gene expression (both transcription and antigen production) and pregenomic RNA encapsidation, as well as the release of HBV virus particles. In contrast, the Ser-53 mutant conferred the same level of suppressive activity as the wild type did. This property is in accordance with the observation that Ser-99 and Ser-116 are the predominant phosphorylation sites in the HCV core construct. All serine mutants (including those with mutations in PKA, PKC, and both kinase recognition sites) of HCV core protein retained the ability to translocate into the nucleus. Furthermore, wild-type HCV core protein diminished its suppressive activity when cells were treated with PKA or PKC inhibitor. In conclusion, HCV core protein is a phospho-protein and in HuH-7 cells, its trans suppression of HBV gene expression and replication is positively regulated by PKA and PKC. The role of phosphorylation in the control of trans-suppressive activity cannot be reproduced by introducing an acidic residue.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Modulation of the trans-suppression activity of hepatitis C virus core protein by phosphorylation. 781 94

Based on theoretical analysis of secondary structure and hydrophilicity data, the region (residues 73-89) of the HBV core-antigen presumably containing the antigenic determinant has been revealed. The epitope mapping of this region with the use of synthetic peptides, obtained by the pin technology and solid phase method, was carried out. Peptides were synthesized in two variants with different amino acids residues in the position 80 (Ala, Ile). Free peptides and their conjugates with bovine serum albumin were tested for antigenicity in ELISA. The results indicate that the fragment 78-83 is the shortest region of the core-antigen which reacts with antibodies from hepatitis B patients sera.
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PMID:[Localization of the immunodominant site in the hepatitis B virus core antigen using synthetic peptides]. 788 Jan 77

The preliminary results of a prospective double-blind controlled trial of colchicine in 100 patients with hepatitis B virus-related cirrhosis are reported. The patients, 94 males and 6 females, aged 32-80, were assigned to receive either 1 mg of colchicine or an identical placebo orally on a daily basis. The duration of the follow up ranged from 15 to 51 months (median 26 months). Seventy percent had histological proof of cirrhosis. On entry, 80 patients were in Child-Pugh class A, 19 were in class B, and one was in class C. Compared to the placebo group, there was no improvement in the colchicine group after a 24-month follow up in any of the biochemistry data, for example, serum albumin, alkaline phosphatase, alanine and aspartate aminotransferase, bilirubin, and prothrombin time. The difference in the cumulative survival rates at 51 months did not reach statistical significance (p = 0.8) in either group. There was no histological improvement in 30 patients who were willing to undergo repeated liver biopsies. No trend toward improvement of the hepatic pressure gradient was observed in these patients. The serum levels of aminopropeptide of type III procollagen increased significantly in patients in both groups after 24 months of therapy (1.07 +/- 0.06 vs. 1.36 +/- 0.06 U/ml in the colchicine group, 0.93 +/- 0.09 vs. 1.25 +/- 0.07 U/ml in the placebo group; p < 0.05). In addition, neither the clinical deterioration of cirrhosis nor death was prevented in patients receiving colchicine therapy. This report indicates that colchicine has no effect in the treatment of HBV-related postnecrotic cirrhosis.
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PMID:A double-blind randomized controlled trial of colchicine in patients with hepatitis B virus-related postnecrotic cirrhosis. 789 Sep 5

The case of a young female patient with chronic active hepatitis B, vasculitic purpura, edema, and circulating immune complexes due to mixed cryoglobulinemia is described. Serum transaminases were elevated. Serological assays showed hepatitis B surface antigen (HBsAg), antibody to hepatitis B e antigen (anti-HBe), and antibody to hepatitis B core antigen (anti-HBc) antibodies but no antibody to hepatitis C virus (anti-HCV) or antibody to hepatitis delta virus (anti-HDV) antibodies. Using hepatitis B virus-polymerase chain reaction (HBV-PCR) and direct sequencing a precore/core (preC/C) mutant unable to synthesize HBeAg was detected in serum. HBV antigens were demonstrated in the circulating immune complexes. Following 1 month of treatment with interferon-alpha 2b3 miu three times weekly, alanine aminotransferases returned to normal levels while cryoglobulins and immune complexes disappeared from serum. In addition, 2 months after the onset of treatment serum HBV-DNA was no longer detectable by PCR. Prior to treatment the analysis of cellular immune reactions of peripheral blood mononuclear cells showed a major proliferative response to HBcAg, preS1Ag and HBxAg and a minor response to HBeAg and HBsAg. One month after conclusion of treatment a decline in T-cell reactivity against all HBV antigens was observed. During clinical response to the therapy, however, a strong proliferative response of T cells to HBcAg and HBeAg was demonstrated. In conclusion, immune complex disease may complicate chronic hepatitis B in patients expressing HBe-minus HBV mutants. Treatment with interferon-alpha was found to be effective in mixed cryoglobulinemia even in the presence of HBe-minus HBV mutants.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Mixed cryoglobulinemia type II in chronic hepatitis B associated with HBe-minus HBV mutant: cellular immune reactions and response to interferon treatment. 789 64

A prospective non-A, non-B follow-up program, implemented in a hepatitis B surface antigen-free dialysis unit, enabled us to report on the natural history of hepatitis C virus (HCV) infection in hemodialyzed patients between 1980 and 1992. For this program, every patient was prospectively monitored every two weeks for alanine amino transferase (ALT) activity, and every month for gammaglutamyl transpeptidase (GGT) activity and systematic collection of frozen sera. Sequences of stored sera from 217 patients were repeatedly tested for anti-HCV antibodies using second generation assays. Eighty-six of the 217 patients (39.6%), including 61 of the 67 patients with non-A, non-B hepatitis (91%), had HCV infection repeatedly evidenced by positive ELISA in all, and confirmed by RIBA in 84 of 86 (97.5%). In addition, 19 out of 23 patients (82.6%) were positive for HCV RNA by the polymerase chain reaction (PCR). Of the 86 anti-HCV positive patients, 41 had previously acquired HCV infection, and 45 seroconverted during chronic dialysis. Of these, all but one patient developed hepatitis with raised ALT activity which lasted for at least six months in all. Only 29 of 45 patients (64.5%) had a history of blood transfusion. Seventy-eight of the 86 patients (91%) who were followed up for one to 11.5 years (median 5) retained anti-HCV for several years. Nineteen liver biopsies performed in 16 patients showed chronic active hepatitis in 8 (50%) and hepatocellular carcinoma without cirrhosis in one patient.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A twelve year natural history of hepatitis C virus infection in hemodialyzed patients. 796 64

We have investigated the role of phosphorylation of the capsid protein of the avian hepadnavirus duck hepatitis B virus in viral replication. We found previously that three serines and one threonine in the C-terminal 24 amino acids of the capsid protein serve as phosphorylation sites and that the pattern of phosphorylation at these sites in intracellular viral capsids is complex. In this study, we present evidence that the phosphorylation state of three of these residues affects distinct steps in viral replication. By substituting these residues with alanine in order to mimic serine, or with aspartic acid in order to mimic phosphoserine, and assaying the effects of these substitutions on various steps in virus replication, we were able to make the following inferences. (i) The presence of phosphoserines at residues 245 and 259 stimulates DNA synthesis within viral nucleocapsids. (ii) The absence of phosphoserine at residue 257 and at residues 257 and 259 stimulates covalently closed circular DNA synthesis and virus production, respectively. (iii) The presence of phosphoserine at position 259 is required for initiation of infection. The results implied that both phosphorylated and nonphosphorylated capsid proteins were necessary for a nucleocapsid particle to carry out all its functions in virus replication, explaining why differential phosphorylation of the capsid protein occurs in hepadnaviruses. Whether these differentially phosphorylated proteins coexist on the same nucleocapsid, or whether the nucleocapsid acquires sequential functions through selective phosphorylation and dephosphorylation, is discussed.
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PMID:Multiple functions of capsid protein phosphorylation in duck hepatitis B virus replication. 820 9

In Brazil, clinicians followed 32 transfusion-dependent beta-thalassemia patients, 1-49 years old, at the Regional Blood Center and the Department of Hematology of University Hospital of the School of Medicine of Ribeirao Preto to determine the prevalence of hepatitis B virus (HBV), hepatitis C virus (HCV), HIV-1, and HTLV-1. They also measured serum levels of ferritin and alanine aspartate transaminase (ALAT) to examine liver iron content and liver damage, respectively. 46.8% tested positive for antibodies to HCV, which was much higher than that of voluntary blood donors of the Regional Blood Center (1.4%) or of other countries. Yet it was about the same as that of multitransfused patients in the UK (23.2%), Italy (92.9%), and Saudi Arabia (33.3%). 3 of these 15 patients also tested positive for HBV markers. 15.5% tested positive only for HBV markers. 37.5% had no hepatitis markers. Hepatitis-positive people were older than those who tested negative for hepatitis (15.2 years vs. 8.5 years; p .05). The number of units of blood transfused and the levels of ferritin and ALAT were not statistically different between the 2 groups (192.1-336 vs. 135.2 and 36.6-52.3 U/l vs. 36.7 U/l, respectively). 75% of the HCV positive patients received more than 100 units of packed red blood cells while only 42% did in the HCV negative group. 2 people tested positive for HIV-1 1 of whom also tested positive for anti-HBs-Ag and the other for HCV antibodies. The HIV-1 cases had become infected before the blood bank began screening for HIV-1 in 1987. None of the patients receiving blood from the center became infected with HIV-1, yet 60% of hemophiliacs treated at the hospital were HIV-1 infected. No one tested positive for HTLV-1, even though all 32 patients had received more than 6250 units of blood not screened for HTLV-1. This reflected the low incidence of HTLV-1 in the general population (0.05%). No one was positive for HBs-Ag or HBe-Ag.
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PMID:The frequency of blood-born viral infections in a population of multitransfused Brazilian patients. 827 57


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