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)

Controlled pore glass (CPG) adsorbs hepatitis B surface antigen (HBsAg) from whole plasma with a high degree of specificity. The resultant complex is stable at acid pH and in the presence of high concentrations of sodium thiocyanate. The adsorbed HBsAg is qualitatively and quantitatively similar to the soluble material in its ability to bind antibodies to HBsAg (anti-HBs). The HBsAg in 1 ml of strongly reactive plasma is adsorbed by 100 mg of CPG, which can then specifically bind 32,000 passive hemagglutination units of anti-HBs. Bound antibody can be eluted in 77% yield by acid or by chaotropic ions and the CPG-HBsAg complex can be reused in further adsorption-elution cycles. Antibody to HBsAg can be purified 144-fold in a single step by using this technique. The preparation of monospecific subtyping reagents for HBsAg and of immunochemically purified anti-HBs is described.
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PMID:A novel immunoadsorbent: use for the preparation of monospecific antibodies to the hepatitis B antigen. 2 34

A new antigen-antibody system was recently described in hepatitis B surface antigen (HBSAG(-positive sera. Despite indications of heterogeneity in specificity, the designations "e antigen" and "e antibodies" are used for the system as such in this articly. E'IGHT OF 17 long-term carriers of HBSAg with a histological picture of chronic persistent hepatitis or chronic aggressive hepatitis carried the e antigen, while none had demonstrable e antibodies in serum. Ten of 12 healthy carriers with e antibodies were blood donors who had donated 95 units of blood; none of these carriers was associeated with a reported case of posttransfusion hepatitis. In five individuals in the incubation stage of hepatitis B, e antigen appeared simultaneously with HBSAg but before the rise in transaminase levels. This finding further links e antigen to hepatitis B.
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PMID:A new antigen-antibody system. Clinical significance in long-term carriers of hepatitis B surface antigen. 4 64

A survey of 128,000 volunteer blood donors from the Greater New York metropolitan area revealed that first-time male donors were positive for hepatitis B surface antigen (HBsAg) 2.5 times more frequently than were first-time female donors; Negroes and Mongols were positive four to 20 times more frequently than Caucasians. The ratio of ad to ay seemed to be higher in non-Caucasian antigen carriers than in Caucasian carriers. Among both Caucasians and non-Caucasians the rate of positivity declined after the age of 50. An excess prevalence of HBsAg was observed in donors with the lowest level of education and in those with the highest level. HBsAg was detectable nine times less frequently among repeat donors than among first-time donors (0.2 vs.1.90 per 1,000). Detection of HBsAg was unrelated to ABO-Rh blood groups. Several mechanisms for these wide variations of antigen detection are possible.
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PMID:Hepatitis B surface antigen in blood donors: further observations. 4 5

A total of 344 sera positive for hepatitis B surface antigen from volunteer blood donors at several Canadian Red Cross centres were subtyped for ad and ay specificity by counterelectrophoresis. Of the 50 sera from Toronto 21 (42%) were ad and 29 (58%) were ay; of the 95 from Montreal 82 (86%) were ad and 13 (14%) were ay; of the 199 from Quebec 179 (90%) were ad and only 20 (10%) were ay. The w and r specificities were also determined in 125 of the samples: 123 were w; the 2 samples of r specificity were from Toronto. On the other hand, among 45 sera from patients with acute hepatitis type B in Quebec 13 (29%) were ad and 33 (71%) ay.
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PMID:Hepatitis B surface antigen: regional variation in sub-type ratio in the Canadian Red Cross donor population. 4 83

A study of 221 patients revealed that detectable hepatitis B surface antigen (HBS Ag) was found in 16.3% of 49 patients who had hepatoma associated with cirrhosis. None of the 8 hepatoma patients without cirrhosis had detectable HBS Ag in the serum. When known causes of cirrhosis were excluded, HBS Ag was present in 18% of 22 patients. Positive alpha-1-fetoprotein (AFP) was found in 25 of 49 cases (51%) of hepatoma with cirrhosis but was found only in 1 of 8 cases (12.5%) of hepatoma without cirrhosis. Of 25 patients whose AFP was positive, HBS Ag was also present in 7. The latter was detected in only 1 of 24 patients in whom AFP was not detected. This study suggests that HBS Ag is closely associated with hepatomas in cirrhotic patients but not in noncirrhotic patients with hepatoma.
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PMID:Relationship of hepatitis B antigen in cirrhosis and hepatoma in Thailand. An etiological significance. 4 28

A total of 2.305 sera positive for hepatitis B surface antigen were obtained from asymptomatic carriers throughout Japan and subtyped for the d, y, w, and r specificities by the hemagglutination inhibition method. Determinant d prevailed in Japan (d, 99.1%; y, 0.9%), and there was no regional variation in its occurrence. In sharp contrast, there was a marked variation in the distribution of the w and r determinants, forming an apparent south-to-north gradient of r. The percentage of r determinant was highest in Kyushu (92%-94%); it decreased gradually along the axis of Japan to the north and was lowest in Akita (46%), which is located at the north end of Honshu.
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PMID:South-to-north gradient in distribution of the r determinant of hepatitis B surface antigen in Japan. 4 83

The prevalences of hepatitis B surface antigen (HBs Ag) subtypes in Thais, Cambodians, and Vietnamese were compared with the prevalences in Americans residing in Southeast Asia. HBs Ag was found with approximately equal frequency in Thai (43 percent) and American (39 percent) patients with hepatitis. However, higher prevalences of HBs Ag were found in asympotomatic Thais (9.5 percent), Cambodians (11.9 percent), and Vietnamese (14.3 percent) than in asymptomatic Americans (0.7 percent). Among asymptomatic Thais, the ratio of HBs Ag/adr to HBs Ag/adw was approximately 10:1, with one exception: adw was not detected in a rural population of northern Thailand. The y determinant was not found in Thais. In contrast, both d and y determinants were found in Americans. These observations conform to a geographic pattern, with ad as the predominant combination in the Far East. In Southeast Asia determinants w and r are more useful epidemiologic markers than y and d.
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PMID:Subtypes of hepatitis B surface antigen in Southeast Asia. 4 31

A lysogenic strain of Pseudomonas aeruginosa was cultured from the dialysis fluid of a patient on chronic hemodialysis treatment whose blood contained hepatitis B surface antigen (HB8Ag). When this bacterium was incubated for 4 to 7 days with serum containing HB8Ag or with purified HB8Ag, a loss of the HB8Ag-specific immunological reactivity was observed. Bacteriophages can be induced from the isolated P. aeruginosa with mitomycin C; the phages, after purification on CsCl gradients, also lyse P. aeruginosa strain 25102 (ATCC). Subsequent to gradient centrifugation of the lysate, a fraction was found with a density around 1.40 g/ml that inactivated HB8Ag after a 4-h incubation at 37 C as determined by counterelectrophoresis and hemagglutination inhibition. The activity was not found in appreciable amounts in other gradient fractions. The electron microscope shows that the active fraction contains envelope vesicles of 45 to 60 nm in diameter. In spite of their loss in HB8Ag activity, the HB8Ag particles (22nm) appeared morphologically intact. These findings suggest that an enzyme(s) is present in the vesicle fraction which inactivates antigenic determinants on HB8Ag particles. Thus, the presence of these bacteria in environments such as feces, dialysis tanks, and contaminated drinking water may prevent the detection of HB8Ag.
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PMID:Interaction of hepatitis B surface antigen (Australia antigen) with membrane vesicles of Pseudomonas aeruginosa. 4 3

Optimal conditions were sought for the radiolabeling of microgram quantities of hepatitis B surface antigen (HBs Ag) employing the chloramine-T or lactoperoxidase iodination procedures. Preparations of HBsAg labeled by these procedures are referred to as chloramine-T preparations and lactoperoxidase preparations, respectively. Labeled HBsAg having specific activities between 10-20 muCi/mug were found to display the greatest degree of sensitivity for unlabeled HBsAg and for anti-HBs using a double-antibody radioimmunoassay (RIA-DA). Increasing the specific activity above this level redulted in a decreased affinity of labeled 1251-HBs Ag for anti-HBs, indicating that soluble antigenic alterations had developed. At equivalent specific activities, chloramine-T preparations competed less effectively for unlabeled HBs Ag than lactoperoxidase preparations, and anti-HBs endpoint titers were slightly reduced, especially among preparations of high specific activity (greater than or equal to 65 muCi/mug). Chloramine-T preparations of HBs Ag (sp. act. 15--30 muCi/mug) showed essentially no antigenic deterioration over a 2-month period at minus 196 degrees C or minus 70 degrees C. Utilization of optimally labeled 1251-HBs Ag has increased the sensitivity of the RIA-DA for unlabeled HBs Ag 30-fold to a level below 1 ng/ml and enhanced antiamine-T method revealed that only the most acidic population was labeled (pH 3.75+/-0.5). In contrast, six antigenic components with distinct pI values ranging from 3.7 to 5.2 were detected by RIA-DA in both unlabeled HBs ag and in the chloramine-T preparation. This indicated that the chloramine-T method did not radically change the relative number or charge of each of the pI populations present in purified preparations of HBs Ag. Analysis of HBs Ag iodinated by the lactoperoxidase procedure revealed the presence of three of four populations of particles with pI values ranging from 3.9 to 4.5, suggesting that this procedure labels HBs Ag more uniformly.
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PMID:Immunological and biophysical properties of hepatitis B antigen labeled by the chloramine-T and by the lactoperoxidase methods. 5 Mar 82

One hundred and three samples from hepatitis B surface antigen (HB(s)Ag) positive Californian blood donors were subtyped in immunodiffusion with respect to d/y, w/r and a21, a23, a3. Spur formation with a human antiserum indicated a previously unrecognized determinant q, which was detected in 96 sera (4 a21yw, 15 a23yw, 69 a21dw and 8 adr). Out of 8 sera which by spur formation were demonstrated to lack q, 7 were further subtyped (2 a21dw and 5 a3dw). Hence all 5 a3 dw specimens were demonstrated to lack q, thus indicating that q is specified by the virus. The possible relation of q to x with further implications for the specification of x is discussed.
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PMID:A new virus specified determinant of hepatitis B surface antigen. 5 Jul 17


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