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)

During the past 10 years, liver transplantation has developed into an established form of treatment. In 1991 alone, almost 450 liver transplants were performed in Germany with a mean 1-year survival of 70%. Consistent progress in the fields of organ preservation, surgical techniques, and prevention of disease recurrence has made a more than 90% 1-year survival rate achievable during the last 3 years in Berlin. Progress in organ preservation is based on the use of colloidal solutions, pharmacological improvement of microcirculation, and probably prevention of reperfusion injury by the use of calcium antagonists and free oxygen radical scavengers. Improvements in surgical techniques have led to a reduction in blood loss and vascular complications, and to a drastic reduction of biliary leaks and stenosis. The introduction of cyclosporin, FK-506, and monoclonal antibodies into immunosuppressive therapy has contributed to the improvement of results in a major way. Furthermore, progress in intensive care in the areas of fluid therapy and blood component substitution, respiratory care and prophylaxis of infection as well as postoperative nutrition has led to a reduction in early postoperative morbidity and mortality. Efficient prophylaxis of the recurrence of hepatitis-B-virus-related disease by using hepatitis B hyperimmunoglobulin after liver transplantation has prevented this lethal recurrence, which was previously frequent, in a large group of patients.
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PMID:[Progress in the field of liver transplantation in the last 10 years]. 149 68

The possibility of obtaining expression of human hepatitis B virus (HBV) genes and production of virus particles in normal liver cells from heterologous species like normal adult rat hepatocytes, by transfecting the complete HBV genome, was investigated. Various techniques for hepatocyte transfection were assayed including the usual calcium-phosphate coprecipitation technique, the Pasco and Fagan modified calcium-phosphate procedure, and the lipofection technique. Transfection efficiency was determined by measuring the production of HBV surface antigen under various culture conditions. Transfection was the most efficient when assayed 1 or 2 days after hepatocyte plating at low density. Few variations in the efficiency were observed between the different transfection procedures. We show that under these culture conditions, replication of HBV can be achieved in differentiated adult rat hepatocytes. Synthesis of relaxed circular and single-stranded DNA forms and of viral transcripts including pregenome RNA occurred in the cells whereas viral antigens and mature and immature viral particles were released into the culture medium. The production of viral proteins was always higher in hepatocytes cocultivated with rat liver epithelial cells and maintained at a low density. In contrast, viral replication was not obtained by transfecting undifferentiated rat liver epithelial cells. These results demonstrate that replication of HBV can occur in hepatocytes from mammalian species non-closely related to primates and strongly support the idea that attachment of the virus and its penetration into the cells are critical steps in the host-specificity of the infection process and that hepatic-specific regulating factors could be essential for viral replication.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Replication of hepatitis B virus in differentiated adult rat hepatocytes transfected with cloned viral DNA. 158 71

Inhibition of human hepatocellular carcinoma (PLC/PRF/5 and Hep3B) or hepatoblastoma (Hep G2) cell lines by inclusion of deferoxamine mesylate (desferrioxamine) (DFX) in the culture medium was evaluated. When PLC/PRF/5 cells were maintained for 7 days in 30 or 60 microM DFX, the cell number was decreased by 30-60%, little or no alpha-fetoprotein (AFP) was produced, and supernatant endpoint dilution titers of hepatitis B surface antigen (HBsAg) were reduced 1-2 logs. PLC/PRF/5 cells maintained for 7 days without DFX (simultaneous controls) grew to confluence, produced AFP that reached 10-60 ng/ml in the supernate, and the HBsAg titer remained constant or increased 1 log. Similar effects were observed in Hep3B and Hep G2 cells maintained in DFX (except that Hep G2 cells do not produce HBsAg), compared to simultaneous control cells grown in the absence of DFX. The growth of a human embryonic lung fibroblast cell line (Wl 38) was not significantly inhibited by DFX, although it grew at a slower rate than simultaneous control cells grown without DFX. Subsequent growth in FeSO4 of PLC/PRF/5, Hep3B, and Hep G2 cells that previously had been maintained in DFX did not reverse the effects of DFX. PLC/PRF/5 cells were also inhibited when maintained in medium containing equimolar concentrations of DFX and FeCl3 and in medium containing equimolar concentrations of DFX and FeSO4. PLC/PRF/5 cells were not inhibited by maintenance in up to 60 microM of another chelating agent that has a similar affinity for iron, calcium disodium versenate (EDTA). These studies show that DFX inhibits the growth of human hepatocellular carcinoma and hepatoblastoma cell lines regardless of the presence (PLC/PRF/5, Hep3B) or absence (Hep G2) of integrated hepatitis B virus DNA. The findings also suggest that the inhibition may have been due to mechanisms other than iron chelation.
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PMID:Inhibition of human hepatocellular carcinoma and hepatoblastoma cell lines by deferoxamine. 171 97

To investigate hepatitis B virus (HBV) biology in vitro, the transfection of recirculized HBV DNA into Chang cell line was performed. Linear HBV DNA was isolated from recombinant HBV DNA, pHBR105, which includes the whole genome of HBV and was recirculized. Chang cells were transfected with this recirculized HBV DNA by the two different procedures of calcium/phosphate coprecipitation and electroporation. After the transfection, the presence of large nucleated cells with multinuclei and ground-glass cytoplasma were noticed and these cells seemed to proliferate faster than untreated Chang cells. Transient expression of hepatitis B virus surface antigen (HBsAg) was demonstrated in cytoplasma of transfected cells by indirect immunofluorescence. HBsAg was not detected in the culture supernatants by radioimmunoassay. The extra-chromosomal HBV DNA was detected in the transfected cells by both procedures 7 weeks after the transfection by Southern blot analysis but it was lost 4 weeks after that. It was demonstrated that it was possible to transfect Chang cells with HBV DNA and that DNA was functioning to express HBsAg transiently.
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PMID:Expression of hepatitis B surface antigen in Chang cells transfected with hepatitis B virus DNA. 221 3

In 1985 a mixture of red cells collected in citrate anticoagulant with plasma derived from heparinized blood was introduced in Amsterdam to perform exchange transfusions in newborns. This heparin mixture has physiological levels of electrolytes, calcium and glucose, can be delivered on short notice and carries a minimal risk of transmission of infectious diseases because all blood components are tested for hepatitis B antigen and antibodies against syphilis and the human immunodeficiency virus. Retrospectively we evaluated 54 children treated in 1986 and 1987 with exchange transfusions using this heparin mixture. An adequate decrease in bilirubin values when necessary was observed while neither changes in sodium, potassium, calcium or glucose values nor adverse effects on the pH value were recorded. However, a remarkable transient thrombocytopenia was found following exchange transfusion with a decrease of the platelet count to an average of 39% of the initial value.
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PMID:[The use of a mixture of citrated erythrocytes and heparin plasma for exchange transfusions]. 221 59

Parvovirus H-1 has been shown to suppress spontaneous and chemically or virally induced tumorigenesis in hamsters. In human cell culture systems propagation of H-1 is restricted to transformed cells, which are killed by H-1 infection, in contrast to normal diploid cells, which are nonpermissive for H-1. By analyzing the permissiveness of a variety of human cells for H-1, it was determined that the majority of tested transformed or immortalized cells which were permissive for H-1 contained the DNA of oncogenic viruses (human papillomavirus, simian virus 40, adenovirus, hepatitis B virus, Epstein-Barr virus, and human T-cell lymphotropic virus type I). Of six transformed cell lines negative for persisting tumor virus DNA, only two were permissive for H-1, while two were semipermissive and two were nonpermissive. Thus, persistence and expression of tumor virus functions appears to promote full permissiveness for H-1 in human cells. However, neither expression of genes of specific viral genomes nor the transformed state of apparently virus-free cells alone was sufficient to render human cells permissive for H-1. Therefore, the effect of tumor virus functions on H-1 in transformed cells seems to be indirect, probably mediated by cellular factors which are induced or switched off during the transformation process. It appears that similar factors are induced or switched off by 5-azacytidine or calcium phosphate, both known inducers of cellular gene expression.
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PMID:Transformation of human cells by oncogenic viruses supports permissiveness for parvovirus H-1 propagation. 249 71

A method of introducing actively expressed genes into intact mammals is described. DNA precipitated with calcium phosphate has been injected intraperitoneally into newborn rats. The injected genes have been taken up and expressed by the animal tissues. To examine the generality of the method we have injected newborn rats with the chloramphenicol acetyltransferase prokaryotic gene fused with various viral and cellular gene promoters and the gene for hepatitis B surface antigen, and we observed appearance of chloramphenicol acetyltransferase activity and hepatitis B surface antigen in liver and spleen. In addition, administration of genes coding for hormones (insulin or growth hormone) resulted in their expression.
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PMID:Direct introduction of genes into rats and expression of the genes. 354 Sep 43

Although a large number of patients are maintained on chronic dialysis, there is little information regarding the medical care rendered to these patients. We therefore obtained information on health care maintenance policies from 90 dialysis centers (8,104 patients) selected from each End-Stage Renal Disease (ESRD) Network. All centers except one obtained BUN, creatinine, electrolytes, calcium, and phosphorus at intervals of 1 month or less; 85% of centers obtained a multiple-test laboratory panel at monthly intervals. Annual physical examination, ECG, and chest x-ray were performed in 80% or more of the centers. Immunization policies varied with 88%, 64%, and 17% of centers offering influenza, pneumococcal, and hepatitis B vaccine, respectively. Patterns of surveillance for anemia, osteodystrophy, and hepatitis were variable. In view of the high frequency and cost of testing, prospective studies to determine optimal methods of health care maintenance in the chronic dialysis center are indicated.
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PMID:Selected health care maintenance policies in chronic dialysis centers. 405 Jul 81

A 21-year-old woman presented with a 12-month history of epigastric pain, and for 3 months she had noticed a mass in the right hypochondrium. She had taken 'Norinyl-1' (norethisterone 1 mg and mestranol 50 mcg) for 5 years. She smoked 20 cigarettes a day but drank little alcohol. Physical examination revealed irregular hard hepatomegaly 10 cm below the right costal margin. Hepatitis B surface antigen was not detected in the serum and alpha fetoprotein levels were normal ( 10 M.R.C. units). A liver scan showed a large space-occupying lesion in the right lobe of the liver, and liver biopsy revealed a cholangicarcinoma with striking fibrous reaction. Multiple shadows consistent with metastases were present on chest X-ray, but no bony deposits were found on radiological skeletal survey or bone scan. The serum calcium was persistently high (2.74-2.92 mmol/l) but fell on prednisolone therapy. Serum parathyroid hormone levels were normal. A causal relation between oral contraceptives and hepatic adenoma is now generally accepted, and several patients with hepatocellular carcinoma have also been reported. We have been able to find only 1 previous report of cholangiocarcinoma in a young female taking oral contraceptives, and there is 1 report of this tumor in a man taking high doses of anabolic steroids for refractory anemia. This tumor has its peak incidence in the 6th decade and is very rare in the 3rd decade. The association with hypercalcemia due to pseudohyperparathyroidism is well recognized. In only some cases are parathyroid hormone levels raised, and the cause of the pseudohypercalcemia in our patient is unknown.
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PMID:Cholangiocarcinoma and oral contraceptives. 610 61

A method for the isolation of complement-fixing immune complexes from human serum and the separation of antigen from antibody is described. In order to isolate the complexes, we used soluble bovine conglutinin in a three-step procedure: (1) serum containing immune complexes is reacted with conglutinin in the presence of 10 mM calcium; (2) the conglutinin-bound immune complexes are precipitated by anti-conglutinin rabbit serum; (3) the precipitate is washed and the complexes are eluted from the precipitate by EDTA (pH 7.5) which chelates calcium and releases C3-associated immune complexes from conglutinin. To separate the antigen from the antibody, the isolated complexes are acid-dissociated (pH 3.0), and the antibody is absorbed to staphylococcal protein A conjugated to Sepharose leaving the antigen in solution. The antibody bound to Sepharose-protein A is recovered by elution with 3.5 M magnesium chloride. This procedure permitted the isolation of immune complexes from sera of hepatitis B surface antigen (HBsAg) positive chronic active hepatitis. In addition, immune complexes were isolated from sera of patients with rheumatoid arthritis, systemic lupus erythematosus and primary biliary cirrhosis. The isolated immune complexes contained IgG, IgM, C3 and albumin. Specific antibodies such as rheumatoid factors, anti-nuclear antibodies and antimitochondrial antibodies in varying titres have been found to be present in the isolated immune complexes. The conglutinin method has proven to be a useful technique for the isolation of immune complexes and for the identification of antibody and could be applied to the identification of the antigen in immune complexes.
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PMID:Isolation of circulating immune complexes by conglutinin and separation of antigen from dissociated complexes by immobilized protein A. 733 70


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