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)

Hepatitis A antigen (HA Ag) was demonstrated by immunofluorescence (IF) in liver biopsies from chimpanzees with experimental hepatitis A virus infection. Blocking experiments with paired sera from patients with hepatitis types A, B, or non-A, non-B, as well as with purified HA Ag, showed that the fluorescence was specific for HA Ag. HA Ag could be demonstrated only in biopsies from chimpanzees inoculated with hepatitis A virus. In two of four chimpanzees biopsied weekly, HA Ag could be detected by IF before stool shedding of HA Ag, elevation in serum alanine aminotransferase (SGPT), or histopathological evidence of liver disease was seen. The HA Ag was detected for 4 to 5 weeks; the last IF-positive biopsy was obtained after SGPT activity had returned to normal. In the two other chimpanzees, HA Ag could be detected only in the biopsy taken at the time of SGPT elevation. In the early IF-positive biopsies, HA Ag was diffusely distributed in the cytoplasm of many cells, but it later accumulated in a focal distribution in the cytoplasm of a few of the hepatocytes and Kupffer cells. This cytoplasmic distribution agrees with previous electron microscopic data.
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PMID:Detection of hepatitis A antigen by immunofluorescence. 20 May 65

Antibodies to polymerized human albumin (poly-HSA) could not be detected by using sensitive methods (enzyme-linked immunosorbent assay and radioimmunoprecipitation) in sera from chronic carriers of hepatitis B surface antigen (HBsAg) or in serial bleedings from one chimpanzee infected with type A hepatitis virus and one infected with non-A, non-B hepatitis virus. By a solid-phase radioimmunoassay, receptor sites for poly-HSA could be detected on HBsAg particles from sera containing either hepatitis B "e" antigen (HBeAg) or anti-HBe. Blocking experiments showed that monomeric HSA did not bind to this receptor. In general, the HBsAg particles from sera with HBeAg had more poly-HSA receptor sites or relatively more particles carrying this receptor compared with HBsAg from sera with anti-HBe. Microtiter plates coated with poly-HSA bound HBsAg from sera containing HBeAg with greater efficiency than did anti-HBs coupled to a solid phase (Ausria II beads), whereas with sera positive for anti-HBe, the two assays were equally sensitive. Decreased ability of HBsAg to bind to poly-HSA was seen in some sera which had been stored for a few years at 4 degrees C, whereas the binding to anti-HBs was unaffected. It is possible that polymers of albumin on the surface of hepatocytes could function as receptors for hepatitis B virus.
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PMID:Sites that bind polymerized albumin on hepatitis B surface antigen particles: detection by radioimmunoassay. 50 Jan 99

Four strains of hepatitis A virus (HAV) were isolated from four fecal samples of patients with type A hepatitis by using primary African green monkey kidney (PAGMK) cells or FRhK-4 cells. In all four samples viral antigen became detectable in PAGMK cells at the 3rd passage level after 9 weeks of incubation; detectable levels of antigen were reached earlier in FRhK-4 cells. An enzyme-linked immunosorbent assay (ELISA) was used to detect HAV antigen (HAV-Ag). Blocking experiments with negative and positive human sera and with paired marmoset sera established the identity of the virus. Infectious virus appeared to be both intracellular and extracellular. Although HAV-Ag could not be detected in culture medium by ELISA, the HAV infectivity titers of culture media were as high as those of cell-associated viruses (greater than 10(6) TCID50/0.2 ml). The passage procedure was simplified by using only virus isolated from cell-free medium as seed material, and the HAV strains were successfully propagated for 12 consecutive passages through PAGMK cells at 2-week intervals. The tissue-culture-produced HAV-Ag proved to be useful as a source of antigen in ELISA for detection of human anti-HAVIgG and IgM. The HAV strains adapted to PAGMK cells lost or decreased their ability to grow in FRhK-4 cells, while one strain adapted to FRhK-4 cells grew equally well in both cell systems.
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PMID:Isolation and adaptation characteristics of hepatitis A virus in primary African green monkey kidney cells: production of antigen useful for ELISA serology. 299 78

Fibrin glue has been used in 22 neurosurgical patients and following five effects which are very much helpful in neurosurgical practice were recognized. Adhesive effect--Dural defect at cranial base was closed with lyophilized dura and fibrin glue. Hemostatic effect--Fibrin glue soaked oxycel was applied for hemostasis of the bleeding from venous sinus, dura, skull edge and cut surface of tumor. Blocking and sealing effects--In cases of craniopharyngioma, cyst wall around the inserted tube was sealed with oxycel and fibrin glue. CSF leakage from open sphenoidal sinus in aneurysmal operation was closed with fibrin glue soaked gelfoam. Covering and wall strengthening effects--Unclippable aneurysms were coated and wrapped with fibrin glue and oxycel. Packing effect--Huge dead space after removal of mucocele was packed with fibrin glue. In trans-sphenoidal operation of pituitary adenoma, fibrin glue soaked muscle pieces and oxycel were packed in the dead space and sphenoidal sinus. Many other possible availabilities in neurosurgical operations were discussed. Fibrin glue is a biological product, so it can be used with more safety and affinity to the local tissue and with less reaction as foreign body than the artificial adhesives. It takes much time for the preparation of this material for the time being. If this can be prepared instantly, usefulness of this glue will be markedly increased. We have had no hepatitis nor inflammatory complications in our limited experience.
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PMID:[The use of fibrin glue in neurosurgical operations]. 387 49

Hepatitis D virus (delta agent) markers were present in 111 (36%) of 308 intravenous drug abusers who were positive for hepatitis B surface antigen (HBsAg), 52 of these having hepatitis D virus antigenaemia. IgM antibody to hepatitis B core antigen (anti-HBc IgM) was present in 92 out of 95 subjects tested, indicating that hepatitis D virus and hepatitis B virus infections had been acquired simultaneously. Hepatitis D virus markers were present in three out of four patients with fulminant hepatitis, and in 80 of 223 (36%) with mild or moderate hepatitis compared with four of 29 (14%) of those who were asymptomatic. These proportional differences were significant (p less than 0.001). Hepatitis D virus markers were present in twice as many patients positive for anti-HBc IgM requiring admission to hospital with acute hepatitis compared with outpatients attending a drug treatment centre. Tests on one patient showed complete disappearance of HBsAg, but hepatitis D antigen (HDAg or delta antigen) and hepatitis B e antigen (HBeAg) were still present in serum samples. All five patients with chronic active hepatitis had hepatitis D antibody (anti-HD) compared with seven of 24 (29%) with chronic persistent hepatitis (p = 0.008). Blocking anti-HD persisted for long periods after simultaneous infections with hepatitis B virus and hepatitis D virus but at lower titres than in patients with chronic liver disease.
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PMID:Increased severity and morbidity of acute hepatitis in drug abusers with simultaneously acquired hepatitis B and hepatitis D virus infections. 392 1

The central role of T cell activation in hepatocellular injury has been well documented. In this article, we provide evidence suggesting that T cells may also play a protective role in liver disease by releasing interleukin-22 (IL-22), a recently identified T cell-derived cytokine whose biological significance is unclear. IL-22 messenger RNA and protein expression are significantly elevated in T cell-mediated hepatitis induced by concanavalin A (ConA) but are less extensively elevated in the carbon tetrachloride-induced liver injury model. Activated CD3(+) T cells are likely responsible for the production of IL-22 in the liver after injection of ConA. The IL-22 receptor is normally expressed at high levels by hepatocytes and further induced after ConA injection. IL-22 blockade with a neutralizing antibody reduces signal transducer and activator of transcription factor 3 (STAT3) activation and worsens liver injury in T cell-mediated hepatitis, whereas injection of recombinant IL-22 attenuates such injury. In vitro treatment with recombinant IL-22 or overexpression of IL-22 promotes cell growth and survival in human hepatocellular carcinoma HepG2 cells. Stable overexpression of IL-22 in HepG2 cells constitutively activates STAT3 and induces expression of a variety of antiapoptotic (e.g., Bcl-2, Bcl-xL, Mcl-1) and mitogenic (e.g., c-myc, cyclin D1, Rb2, CDK4) proteins. Blocking STAT3 activation abolishes the antiapoptotic and mitogenic actions of IL-22 in hepatic cells. In conclusion, the T cell-derived cytokine IL-22 is a survival factor for hepatocytes; this suggests that T cell activation may also prevent and repair liver injury by releasing hepatoprotective cytokine IL-22 in addition to its previously documented central role in hepatocellular injury.
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PMID:Interleukin 22 (IL-22) plays a protective role in T cell-mediated murine hepatitis: IL-22 is a survival factor for hepatocytes via STAT3 activation. 1512 62

It is well-documented that alcohol drinking together with hepatitis viral infection accelerates liver injury; however the underlying mechanisms remain unknown. In this paper, we demonstrated that primary hepatocytes from transgenic mice overexpressing hepatitis B virus X protein (HBX) were more susceptible to ethanol- and TNF-alpha-induced apoptotic killing. Compared to normal control mouse hepatocytes, ethanol and/or TNF-alpha treatment led to a significant increase in reactive oxygen species, mitochondrial permeability transition, cytochrome C release, caspase-3 activity, and poly (ADP-ribose) polymerase degradation in hepatocytes from HBX transgenic mice. Blocking caspase-3 activity antagonized ethanol- and TNF-alpha-induced apoptosis in primary hepatocytes from HBX transgenic mice. Taken together, our findings suggest that HBX sensitizes primary mouse hepatocytes to ethanol- and TNF-alpha-induced apoptosis by a caspase-3-dependent mechanism, which may partly explain the synergistic effects of alcohol consumption and hepatitis B virus infection on liver injury.
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PMID:Hepatitis B virus X protein sensitizes primary mouse hepatocytes to ethanol- and TNF-alpha-induced apoptosis by a caspase-3-dependent mechanism. 1621 10

The chemokine CXCL10 is expressed within the CNS in response to intracerebral infection with mouse hepatitis virus (MHV). Blocking CXCL10 signaling results in increased mortality accompanied by reduced T cell infiltration and increased viral titers within the brain suggesting that CXCL10 functions in host defense by attracting T cells into the CNS. The present study was undertaken to extend our understanding of the functional role of CXCL10 in response to MHV infection given that CXCL10 signaling has been implicated in coordinating both effector T cell generation and trafficking. We show that MHV infection of CXCL10(+/+) or CXCL10(-/-) mice results in comparable levels of T cell activation and similar numbers of virus-specific CD4+ and CD8+ T cells. Subsequent analysis revealed no differences in T cell proliferation, IFN-gamma secretion by virus-specific T cells, or CD8+ T cell cytolytic activity. Analysis of chemokine receptor expression on CD4+ and CD8+ T cells obtained from MHV-immunized CXCL10(+/+) and CXCL10(-/-) mice revealed comparable levels of CXCR3 and CCR5, which are capable of responding to ligands CXCL10 and CCL5, respectively. Adoptive transfer of splenocytes acquired from MHV-immunized CXCL10(-/-) mice into MHV-infected RAG1(-/-) mice resulted in T cell infiltration into the CNS, reduced viral burden, and demyelination comparable to RAG1(-/-) recipients of immune CXCL10(+/+) splenocytes. Collectively, these data imply that CXCL10 functions primarily as a T cell chemoattractant and does not significantly influence T cell effector response following MHV infection.
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PMID:T cell antiviral effector function is not dependent on CXCL10 following murine coronavirus infection. 1714 34

Cyclooxygenases (COXs) play a significant role in many different viral infections with respect to replication and pathogenesis. Here we investigated the role of COXs in the mouse hepatitis coronavirus (MHV) infection cycle. Blocking COX activity by different inhibitors or by RNA interference affected MHV infection in different cells. The COX inhibitors reduced MHV infection at a post-binding step, but early in the replication cycle. Both viral RNA and viral protein synthesis were affected with subsequent loss of progeny virus production. Thus, COX activity appears to be required for efficient MHV replication, providing a potential target for anti-coronaviral therapy.
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PMID:Cyclooxygenase activity is important for efficient replication of mouse hepatitis virus at an early stage of infection. 1755 80

Inoculation with the neurotropic JHM strain of mouse hepatitis virus (JHMV) into the central nervous system (CNS) of mice results in an acute encephalitis associated with an immune-mediated demyelinating disease. During acute disease, infiltrating CD8(+) T cells secrete gamma interferon (IFN-gamma) that controls replication in oligodendrocytes, while infected astrocytes and microglia are susceptible to perforin-mediated lysis. The present study was undertaken to reveal the functional contributions of the activating NKG2D receptor in host defense and disease following JHMV infection. NKG2D ligands RAE-1, MULT1, and H60 were expressed within the CNS following JHMV infection. The immunophenotyping of infiltrating cells revealed that NKG2D was expressed on approximately 90% of infiltrating CD8(+) T cells during acute and chronic disease. Blocking NKG2D following JHMV infection resulted in increased mortality that correlated with increased viral titers within the CNS. Anti-NKG2D treatment did not alter T-cell infiltration into the CNS or the generation of virus-specific CD8(+) T cells, and the expression of IFN-gamma was not affected. However, cytotoxic T-lymphocyte (CTL) activity was dependent on NKG2D expression, because anti-NKG2D treatment resulted in a dramatic reduction in lytic activity by virus-specific CD8(+) T cells. Blocking NKG2D during chronic disease did not affect either T-cell or macrophage infiltration or the severity of demyelination, indicating that NKG2D does not contribute to virus-induced demyelination. These findings demonstrate a functional role for NKG2D in host defense during acute viral encephalitis by selectively enhancing CTL activity by infiltrating virus-specific CD8(+) T cells.
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PMID:NKG2D receptor signaling enhances cytolytic activity by virus-specific CD8+ T cells: evidence for a protective role in virus-induced encephalitis. 1816 Apr 33


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