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)

Treatment of hepatitis B surface antigen (HBsAg) with either chloroform-methanol (2:1, v/v) or 50% 1,1',3,3'-tetramethylurea did not affect the morphological integrity of the particles (about 20 nm in diameter), although the major portion of lipids was released as indicated by their increased buoyant density in CsCl (1.27 g/cm3 as compared with 1.20 g/cm3 for intact HBsAg). The antigenicity and polypeptide composition of HBsAg was not altered by delipidation. The carbohydrate chains of HBsAg contain penultimate beta-D-galactosyl residues. HBsAg was cleaved by chymotrypsin into fragments which were smaller than intact HBsAg by two orders of magnitude and which contained both the a and d determinants.
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PMID:Properties of delipidated hepatitis B surface antigen (HBsAg) and preparation of its proteolytic cleavage fragments carrying HBsAg-specific antigenic determinants. 7 67

Using a double polymerase chain reaction a method was devised for detecting and subtyping hepatitis B virus DNA in serum samples. Primers from the S-gene were selected from the sequence analyses of five HBV HBsAg subtypes, to amplify HBV DNA and subtype for y specific DNA. Thirty-eight samples were subtyped for d and y determinants by radioimmunoprecipitation assay (RIPA) and the polymerase chain reaction (PCR). Subtyping by PCR and RIPA was in agreement in 100% of subtype y samples and 83.3% of subtype d, giving an overall correlation of 92.1%. As a third comparison, 12 amplified samples were digested by the restriction enzyme Sau 3A, which differentiates between subtypes y and d. The digest results agreed with PCR in 83.3% of the samples. In addition, we compared our standard phenol/chloroform extraction against a rapid one step method. The phenol/chloroform stage was found to be essential for the removal of nucleases and polymerase inhibitors present in sera.
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PMID:Comparison of hepatitis B virus subtyping of d/y determinants by radioimmunoprecipitation assay and the polymerase chain reaction. 134 39

A rapid single-step procedure for the isolation of low molecular weight DNA using guanidinium thiocyanate and phenol as protein denaturants is described and applied for the detection of specific hepatitis B virus (HBV) DNA sequences from serum samples by the polymerase chain reaction (PCR). The novel technique is efficient and, when compared to the standard proteinase K/phenol/chloroform method has the advantage of being faster and easily adaptable to the routine processing of a high number of clinical samples by PCR and spot hybridization techniques.
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PMID:A single-step DNA extraction procedure for the detection of serum hepatitis B virus sequences by the polymerase chain reaction. 165 51

To evaluate the effects of P. amarus on hepatitis B virus (HBV) antigens and HBV-DNA, initial ethanolic extract and subsequent fractions of the plants were prepared. The whole plant material was dried, powdered and extracted with alcohol and subsequently fractionated in hexane, chloroform, butanol and finally in water. All the material were tested for in vitro effects on HBsAg, HBeAg and HBV-DNA in serum samples positive for HBV antigens followed by the screening of respective antigens by Elisa. HBV-DNA was determined by molecular hybridization. The extracts were effective against HBV antigens, the butanol extract being the most potent. Further chromatographic fractions showed an enhanced activity. The active fractions inhibited the interaction between HBsAg/HBeAg and their corresponding antibodies suggesting anti-HBs, anti-HBe-like activity and also an effect on HBV-DNA.
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PMID:In vitro effect of Phyllanthus amarus on hepatitis B virus. 185 21

Sequences of hepatitis B virus DNA were detected specifically in the sera of infected individuals by a non-radioactive riboprobe nucleic acid hybridization assay. The nucleic acids contained in serum specimens were prepared by an overnight proteinase K-/SDS-digest, phenol/chloroform-extraction and ethanol-precipitation, and immobilized on nylon membranes by the dot-blot technique. Digoxigenin-labelled 1.4 kb RNA-probes were generated by the phage sp 6 RNA-polymerase from a linearized HBV DNA transcription template containing the appropriate promoter. Hybridized probes were detected by alkaline phosphatase-conjugated sheep anti-digoxigenin Fab-fragments, and 5-bromo-4-chloro-3-indolylphosphate (BCIP) and nitroblue tetrazolium salt (NBT) as chromogenic substrates for the subsequent ELISA procedure. With a detection limit of 0.5-1.0 pg HBV DNA and a high specificity, the results were comparable to those obtained by the standard assay employing radioactively labeled DNA-probes.
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PMID:A nonradioactive riboprobe assay for the detection of hepatitis B virus DNA in human sera. 208

Posttransfusion non-A, non-B hepatitis associated with the formation of hepatocyte cytoplasmic tubules was experimentally transmitted to chimpanzees by intravenous inoculation of a proven-infectious plasma that had been pelleted and microfiltrated, or purified by a combination of pelleting and rate-zonal banding. The results of these studies indicate that a factor VIII-derived non-A, non-B tubule-forming agent will pass through an 80-nm membrane filter and that it can be recovered from infected plasma by use of a purification procedure that assumes the non-A, non-B tubule-forming agent is a small, enveloped virus. Our findings, in combination with the known sensitivity of the non-A, non-B tubule-forming agent to chloroform and its apparent lack of nucleic acid homology with hepatitis B virus, further suggest that at least one etiologic agent of human posttransfusion non-A, non-B hepatitis may be a small, enveloped RNA virus.
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PMID:Posttransfusion non-A, non-B hepatitis in chimpanzees. Physicochemical evidence that the tubule-forming agent is a small, enveloped virus. 298 54

We carried out safety studies in 45 previously untreated patients with congenital coagulatory defects, who needed to be treated with clotting factor concentrates. Non-A, non-B hepatitis developed in patients who received dry heated F VIII preparations with or without chloroform, but not in those who were infused with hot-steam treated F VIII or chromatography treated F IX. Hepatitis B developed in 3 unvaccinated patients who received the same lot of hot steam treated F VIII. None of the 45 patients we have investigated developed HTLV-III/LAV antibody. Thus, dry heating of concentrates does not prevent hepatitis transmission. Hot-steam and hydrophobic interaction chromatography seem to be more effective in preventing hepatitis transmission, but not completely safe. All the above procedures except hot steam seem to protect from hepatitis B. They all seem to prevent HTLV-III/LAV transmission.
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PMID:Clinical studies with treated clotting factor concentrates. 303 39

To determine whether a non-A, non-B hepatitis agent contained essential lipids, we extracted with chloroform a dilution of human plasma that contained approximately 10(4) chimpanzee infectious doses of non-A, non-B hepatitis virus and then tested for infectivity in chimpanzees. In addition, we treated a serum containing hepatitis B virus in the same way. Both of these samples were also sham extracted as controls. Known chloroform-sensitive and chloroform-resistant viruses were added directly to the hepatitis-containing serum or plasma as internal controls or to fetal calf serum as external controls and were assayed for infectivity in vitro after chloroform extraction or sham extraction. All infectivity of the diluted plasma that contained at least 10(4) chimpanzee infective doses of non-A, non-B hepatitis agent and all infectivity of the serum that contained 10(3.5) chimpanzee infective doses of hepatitis B virus were destroyed by chloroform. The chloroform-sensitive control viruses were completely inactivated, but the chloroform-resistant control viruses lost less than 0.5 log10 of infectivity. Sham-extracted non-A, non-B hepatitis agent-containing plasma was shown to maintain its infectivity in chimpanzees that had initially been inoculated with the chloroform-extracted plasma. Thus, both hepatitis type B and non-A, non-B hepatitis appear to be caused by viruses that can be inactivated by a lipid solvent.
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PMID:Inactivation of hepatitis B virus and non-A, non-B hepatitis by chloroform. 640 13

Hepatitis B virus (HBV) DNA was detected by direct spotting of alkali-denatured serum on a nitrocellulose filter and molecular hybridization with cloned HBV DNA as the probe. Measurement of the autoradiographic signals as the intensity of hybridization allowed the quantitation of HBV DNA content in serum specimens in reference to cloned HBV DNA. Direct spotting of denatured serum was approximately three times as sensitive as the conventional method in which proteinase-treated serum was extracted with phenol-chloroform. The intensity of hybridization with 25 specimens of HB virion concentrates correlated well with DNA polymerase activity (r = 0.89, P less than 0.01).
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PMID:Determination of hepatitis B virus DNA in serum by molecular hybridization. 652 67

Chloroform, 40% formaldehyde, 3% hydrogen peroxide solution and 75% alcohol were used to act on hepatitis B surface antigen (HBeAg), hepatitis B e antigen (HBaAg) and anti-hepatitis C virus antibody (Anti-HCV) positive serum for 5, 15, 30 and over 60 minutes. They were examined by enzyme-linked immunosorbent assay and observed for the effect. The destructive effect of chloroform on HBsAg and anti-HCV positive derum was marked. It was discovered that 40% formaldehyde solution destroyed HBsAg, HBeAg, and anti-HCV positive serm, while 75% alcohol also showed destructive effect on HBsAg, HBeAg and anti-HCV positive serum.
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PMID:[Preliminary observation on the destructive effect of chemical disinfectants in serum markers of hepatitis B and C]. 754 43


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