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)

Production of the antiviral cytokine, tumor necrosis factor-alpha is increased in chronic hepatitis B virus infection, and clinical studies of tumor necrosis factor-alpha have indicated a proviral effect at higher doses. To determine whether this might be related to abnormal cell surface tumor necrosis factor-alpha receptor expression, binding characteristics of cell surface tumor necrosis factor-alpha receptor on peripheral blood mononuclear cells in chronic hepatitis B virus carriers were studied using radioiodinated recombinant tumor necrosis factor-alpha. The specific binding curves generated were analyzed according to the method of Scatchard to determine cell surface receptor numbers and dissociation constants. A single class of cell surface tumor necrosis factor-alpha receptor was demonstrated on peripheral blood mononuclear cells and mononuclear subsets. The median number (range) of cell surface tumor necrosis factor-alpha receptors on peripheral blood mononuclear cells from controls (n = 11), chronic hepatitis B virus patients seropositive for hepatitis B virus DNA (n = 8) and seronegative for hepatitis B virus DNA (n = 8) were 2,329 (range = 1,538 to 3,133), 3,375 (range = 2,300 to 6,718) (p less than 0.01) and 3,113 (range = 2,229 to 5,246) (p less than 0.05) sites/cell, respectively. They all had similar dissociation constants of 8.4 x 10(-10) mol/L (range = 4.1 to 16.9), respectively. Further dissection of the peripheral blood mononuclear cells showed that this increase in cell surface receptor number was confined to the monocyte fraction (p less than 0.01). Plasma tumor necrosis factor-alpha levels in five patients with increased monocyte cell surface tumor necrosis factor-alpha receptor numbers were also elevated.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Increased tumor necrosis factor-alpha receptor number in chronic hepatitis B virus infection. 164 38

The effect of prostaglandins (PG) in patients with fulminant and subfulminant viral hepatitis was studied. Seventeen patients presented with FHF secondary to hepatitis A (N = 3), hepatitis B (N = 6) and non-A, non-B (NANB) hepatitis (N = 8). Fourteen of the 17 patients had stage III or IV hepatic encephalopathy (HE). At presentation, the mean AST was 1844 +/- 1246 units/liter, bilirubin 232 +/- 135 mumol/liter, PT 34 +/- 18 and PTT 73 +/- 26 sec, and coagulation factors V and VII were 8 +/- 4 and 9 +/- 51%, respectively. Twelve of 17 patients responded to PGE1 rapidly, with a decrease in AST from 1540 +/- 833 to 188 +/- 324 units/liter, a decrease in prothrombin time from 27 +/- 7 sec to 12 +/- 1 sec, PTT from 61 +/- 10 sec to 31 +/- 2 sec, and an increase in factor V from 9 +/- 4% to 69 +/- 18% and factor VII from 11 +/- 5% to 71 +/- 20%. Five responders with NANB hepatitis relapsed upon discontinuation of therapy, with recurrence of HE and increases in AST and PT but improvement was observed upon retreatment. After four weeks of intravenous therapy, oral PGE2 was substituted. Two patients have recovered completely and remain in remission six and 12 months following cessation of therapy. Two additional patients continue in remission after two and six months of PGE2. No relapses have been seen in patients with hepatitis A virus (HAV) or hepatitis B virus (HBV) infection. Liver biopsies in the 12 surviving patients have returned to normal. These results suggest efficacy of PGE for FHF. Further investigation is warranted.
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PMID:Treatment of fulminant viral hepatic failure with prostaglandin E. A preliminary report. 190 42

The effect of PG on patients with fulminant and subfulminant viral hepatitis (FHF) was studied. 17 patients presented with FHF secondary to hepatitis A (n = 3), hepatitis B (n = 6), and non-A, non-B (NANB) hepatitis (n = 8). 14 of the 17 patients had stage III or IV hepatic encephalopathy (HE). At presentation the mean aspartate transaminase (AST) was 1,844 +/- 1,246 U/liter, bilirubin 232 +/- 135 mumol/liter, prothrombin time (PT) 34 +/- 18, partial thromboplastin time (PTT) 73 +/- 26 s, and coagulation Factors V and VII 8 +/- 4 and 9 +/- 5%, respectively. Intravenous PGE1 was initiated 24-48 h later after a rise in AST (2,195 +/- 1,810), bilirubin (341 +/- 148), PT (36 +/- 15), and PTT (75 +/- 18). 12 of 17 responded rapidly with a decrease in AST from 1,540 +/- 833 to 188 +/- 324 U/liter. Improvement in hepatic synthetic function was indicated by a decrease in PT from 27 +/- 7 to 12 +/- 1 s and PTT from 61 +/- 10 to 31 +/- 2 s, and an increase in Factor V from 9 +/- 4 to 69 +/- 18% and Factor VII from 11 +/- 5 to 71 +/- 20%. Five responders with NANB hepatitis relapsed upon discontinuation of therapy, with recurrence of HE and increases in AST and PT, and improvement was observed upon retreatment. After 4 wk of intravenous therapy oral PGE2 was substituted. Two patients with NANB hepatitis recovered completely and remained in remission 6 and 12 mo after cessation of therapy. Two additional patients continued in remission after 2 and 6 mo of PGE2. No relapses were seen in the patients with hepatitis A virus and hepatitis B virus infection. Liver biopsies in all 12 surviving patients returned to normal. In the five nonresponders an improvement in hepatic function was indicated by a fall in AST (3,767 +/- 2,611 to 2,142 +/- 2,040 U/liter), PT (52 +/- 25 to 33 +/- 18 s), and PTT (103 +/- 29 to 77 +/- 44 s), but all deteriorated and died of cerebral edema (n = 3) or underwent liver transplantation (n = 2). These results suggest efficacy of PGE for FHF, and further investigation is warranted.
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PMID:Biochemical and clinical response of fulminant viral hepatitis to administration of prostaglandin E. A preliminary report. 279 44

Fulminant hepatic failure is defined as the development of hepatic encephalopathy within 8 weeks of the onset of illness. While there are many causes of FHF, viral hepatitis, particularly hepatitis B, remains the most common etiology. Several drugs and toxins can also lead to FHF, most notably acetaminophen. Even with improvements in ICU care, mortality remains very high for these patients. Conservative management focuses on invasive monitoring and the prevention and treatment of complications like cerebral edema, infection, renal failure, and coagulopathy. Only orthotopic liver transplantation has reduced mortality from 80% to 30% to 50%. Therefore, the goals of management and treatment now include determining which patients are appropriate for liver transplant and finding a donor in a timely fashion.
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PMID:Diagnosis and management of fulminant hepatic failure. 779 72

The present study describes the frequency of hepatitis viral markers in patients with uncomplicated acute viral hepatitis (AVH; n = 32) and in patients with severe liver diseases, including those with fulminant hepatic failure (FHF; n = 110), subacute hepatic failure (SAHF; n = 65), and chronic active hepatitis (CAH; n = 33). The results indicate that hepatitis A virus infection is quite rare, whereas hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the predominant causes of acute and chronic liver failure in India. The incidence of HBV infection in AVH, FHF, SAHF, and CAH groups was recorded in 3.7, 19.1, 23.1, and 69.7% of the cases, respectively. Similarly, HCV infection in these four groups was noted in 12.5, 45, 44.6, and 48.5% of the cases, respectively. Further analysis of HCV infection demonstrated that it was as frequent as single infection in acute cases, but more commonly found in association with HBV infection in chronic liver failure cases. Hepatitis D virus (HDV) infection, as indicated by the presence of IgM anti-HDV antibodies, was recorded in 7.3% of the cases with AVH, in 7.3% of the cases with FHF, in 9.2% of the cases with SAHF, and in 6.1% of the cases with CAH. HDV was associated with HBV both as superinfection as well as coinfection. Interestingly, nearly 2-6% of the cases in each group showed the presence of simultaneous HBV, HCV, and HDV infection. 83.3% of the AVH, 42.1% of the FHF, 37.0% of the SAHF, and 15.1% of the CAH patients had unknown viral markers.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Status of hepatitis viral markers in patients with acute and chronic liver diseases in northern India. 858 38

In response to viruses, monocytes and B cells produce TNF alpha. Therefore, we investigated TNF alpha gene expression and protein secretion in a human monocytic cell line, THP-1, and a Burkitt's lymphoma B-cell line, Namalwa, in response to hepatitis B virus (HBV). Stimulation by phorbol myristate acetate (PMA) (100 ng/ml for 48 h) induced TNF alpha secretion in THP-1 and Namalwa cells (100 to 300 pg/ml). In THP cells, the optimum response (> 2000 pg/ml) was obtained in the presence of a second mitogenic signal such as lipopolysaccharide (LPS) (10 microg/ml for 24 h). In our activation conditions, Northern blot analysis revealed a marked accumulation of TNF alpha mRNA species at 1.7 kb in both cell lines. When PMA- or PMA+LPS-stimulated THP-1 cells were exposed to HBV, TNF alpha protein and mRNA significantly decreased (> 50%). In contrast, HBV exposure of PMA-activated Namalwa cells resulted in strongly increased TNF alpha protein secretion (1 ng/ml). In this case, HBV induced TNF alpha mRNA accumulation that consisted of two types: a regular 1.7 kb and two novel high molecular weight (HMW) species at 3.7 and 4.3 kb. Exposure of stimulated THP-1 and Namalwa cells to HBV resulted in HBs and pre-S1 antigen production in the supernatants. In addition, HMW HBV DNA forms were detected in both cell lines, but with distinct HindIII restriction patterns. These findings indicate that TNF alpha gene expression may be differently regulated by HBV in activated human macrophages and B cells, and thus TNF alpha may be involved in the pathogenesis of HBV.
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PMID:Effect of hepatitis B virus on tumour necrosis factor (TNF alpha) gene expression in human THP-1 monocytic and Namalwa B-cell lines. 944 79

A total of 238 sera samples from cases of hepatitis, renal failure, thalassaemia, healthy health care workers (HCWs) & asymptomatic HBsAG carriers coming from central India from July 1992 to June 1998, were screened for anti-delta antibodies. Among 238 subjects, 206 were reactive for hepatitis B surface antigen (HBsAg) while 32 were HBsAg non-reactive. The prevalence of anti-delta antibodies was low (1.9%) among 54 patients of acute viral hepatitis (AVH) while it was higher (5.7%) among 52 patients of chronic liver disease (CLD). The anti-delta antibodies positivity among 34 patients with hepatic failure was around 15% and all of them were FHF patients. Among multitransfused subjects such as chronic renal failure (CRF) the prevalence of anti-delta antibodies was low (2.3%). None of the apparently healthy HBsAg reactive HCWs and asymptomatic HBV carriers were reactive for anti-delta antibodies. Similarly anti-delta antibodies could not be detected in HBsAg negative viral hepatitis patients. There is a wide variation in the prevalence of anti-delta antibodies in different parts of India. However, overall prevalence of anti-delta antibodies appears to be lower in the Indian population in comparision to western countries.
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PMID:Prevalence of anti-delta antibodies in central India. 1046 45

Tumor necrosis factor (TNF) plays a role in the pathogenesis of chronic hepatitis B (CHB) and chronic hepatitis C (CHC). The difference in the cytokine responses between hepatitis B virus (HBV) and hepatitis C virus (HCV) infections may have implications in the pathogenesis of these diseases. We performed a comparative study to examine the possible differences in the TNF-TNF receptor (TNFR) response between CHB and CHC. We studied the cytokine levels of 38 patients with CHB, 40 patients with CHC and 9 patients with dual hepatitis B and C, and compared them with the baseline levels of 12 healthy controls. The plasma levels of TNF-alpha, interferon-gamma, interleukin (IL)-2, IL-4, IL-10 and soluble TNFR-1 and 2 (sTNFR-1 and 2) were quantified by enzyme-linked immunosorbent assays. The expression of TNFR-1 and 2 in liver tissues was examined in 30 cases of CHB and 15 cases of CHC by semiquantitative reverse transcription polymerase chain reaction. The results showed that sTNFR-1 levels correlated with liver inflammation in all patients, whereas this correlation was not found with sTNFR-2 or other cytokines. Liver inflammation indicators were higher in HCV RNA+ than in HCV RNA- CHC. Most significantly, sTNFR-1 levels correlated with liver inflammation in CHB, but not in CHC. However, the expression of TNFR-1 and 2 in liver was similar between CHB and CHC. These findings suggest that the TNFR signal transduction pathway is modulated differently in HBV and HCV infection.
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PMID:Modulation of tumor necrosis factor receptors 1 and 2 in chronic hepatitis B and C: the differences and implications in pathogenesis. 1145 94

Activation of the cellular stress pathways (c-Jun N-terminal kinase [JNK] and p38 mitogen-activated protein [MAP] kinase) is linked to apoptosis. However, whether both pathways are required for apoptosis remains unresolved. Hepatitis B virus X protein (pX) activates p38 MAP kinase and JNK pathways and, in response to weak apoptotic signals, sensitizes hepatocytes to apoptosis. Employing hepatocyte cell lines expressing pX, which was regulated by tetracycline, we investigated the mechanism of apoptosis by p38 MAP kinase and JNK pathway activation. Inhibition of the p38 MAP kinase pathway rescues by 80% the initiation of pX-mediated apoptosis, whereas subsequent apoptotic events involve both pathways. pX-mediated activation of p38 MAP kinase and JNK pathways is sustained, inducing the transcription of the death receptor family genes encoding Fas/FasL and tumor necrosis factor receptor 1 (TNFR1)/TNF-alpha and the p53-regulated Bax and Noxa genes. The pX-dependent expression of Fas/FasL and TNFR1/TNF-alpha mediates caspase 8 activation, resulting in Bid cleavage. In turn, activated Bid, acting with pX-induced Bax and Noxa, mediates the mitochondrial release of cytochrome c, resulting in the activation of caspase 9 and apoptosis. Combined antibody neutralization of FasL and TNF-alpha reduces by 70% the initiation of pX-mediated apoptosis. These results support the importance of the pX-dependent activation of both the p38 MAP kinase and JNK pathways in pX-mediated apoptosis and suggest that this mechanism of apoptosis occurs in vivo in response to weak apoptotic signals.
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PMID:Sustained activation of p38 mitogen-activated protein kinase and c-Jun N-terminal kinase pathways by hepatitis B virus X protein mediates apoptosis via induction of Fas/FasL and tumor necrosis factor (TNF) receptor 1/TNF-alpha expression. 1554 43

To better define the mechanism(s) likely responsible for viral clearance during hepatitis B virus (HBV) infection, viral clearance was studied in a panel of immunodeficient mouse strains that were hydrodynamically transfected with a plasmid containing a replication-competent copy of the HBV genome. Neither B cells nor perforin were required to clear the viral DNA transcriptional template from the liver. In contrast, the template persisted for at least 60 days at high levels in NOD/Scid mice and at lower levels in the absence of CD4(+) and CD8(+) T cells, NK cells, Fas, IFN-gamma (IFN-gamma), IFN-alpha/beta receptor (IFN-alpha/betaR1), and TNF receptor 1 (TNFR1), indicating that each of these effectors was required to eliminate the transcriptional template from the liver. Interestingly, viral replication was ultimately terminated in all lineages except the NOD/Scid mice, suggesting the existence of redundant pathways that inhibit HBV replication. Finally, induction of a CD8(+) T cell response in these animals depended on the presence of CD4(+) T cells. These results are consistent with a model in which CD4(+) T cells serve as master regulators of the adaptive immune response to HBV; CD8(+) T cells are the key cellular effectors mediating HBV clearance from the liver, apparently by a Fas-dependent, perforin-independent process in which NK cells, IFN-gamma, TNFR1, and IFN-alpha/betaR play supporting roles. These results provide insight into the complexity of the systems involved in HBV clearance, and they suggest unique directions for analysis of the mechanism(s) responsible for HBV persistence.
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PMID:Immune effectors required for hepatitis B virus clearance. 2008 Jul 55


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