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Biomedical subjects

B S Blumberg

Publications and source records attributed to B S Blumberg.

At least 19 recordsLinked to original sources
PubMed1992

Analysis of a cellular model to account for the natural history of infection by the hepatitis B virus and its role in the development of primary hepatocellular carcinoma.

Infection with the hepatitis B virus (HBV) can have many different outcomes. Transient infection may result in acute hepatitis or may remain subclinical. Persistent infection may also be subclinical, or may involve chronic active hepatitis, and can finally lead to the development of primary hepatocellular carcinoma. A mathematical model is given to account for the many different outcomes of HBV pathogenesis. The model is based on the assumption that the liver contains two cell populations with differing abilities to support active HBV replication and/or viral integration into the genome. The model helps account for the relationship of the different clinical courses of HBV infection to the age when the disease is acquired, together with the state of the immune system of the patient.

Carcinoma, Hepatocellular↗
PubMed1992

Hepatitis B x antigen and polymerase antibodies in the serum of hepatitis B carriers with or without hepatitis delta virus infection. Effects of interferon treatment.

Previous work has shown that the hepatitis B x antigen (HBxAg) and antibodies directed against the polymerase of hepatitis B virus (anti-pol) are early markers of hepatitis B virus (HBV) replication in natural infections. The present study was carried out to test the hypothesis that the appearance of one or both of these markers signaled reactivation in chronic carriers with liver disease who were treated with alpha-interferon (IFN). The results show that HBV DNA decreased among the patients who responded to therapy, and that among these responders, neither HBxAg nor anti-pol became detectable in serum for 12 months after treatment, in contrast to controls. Hence, the loss of HBxAg and anti-pol correlate with decreased levels of HBV DNA in response to IFN therapy. However, different patterns of HBxAg and anti-pol were observed among alpha-IFN-treated HBV carrier patients who were also chronically infected with the hepatitis delta virus (HDV). The treatment of such patients often resulted in the loss of HDV RNA from serum and delta antigen from liver. Most of these patients had increased levels of HBV DNA in serum. HBxAg and/or anti-pol also became detectable in patients who lost markers of HDV, implying that the suppression of HDV by IFN is accompanied by the appearance of early markers of HBV reactivation in some of the treated patients.

Adult↗
PubMed1992

Usage and bioassays in Phyllanthus (Euphorbiaceae): a compilation. III. The subgenera Eriococcus, Conami, Gomphidium, Botryanthus, Xylophylla and Phyllanthodendron, and a complete list of the species cited in the three-part series.

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published in four papers, including (in Part IV) analysis, discussion and conclusions concerning apparent clustering of some uses or effects within taxa. This paper (Part III) covers the subgenera Eriococcus, Conami, Gomphidium, Botryanthus, Xylophylla and Phyllanthodendron, and also includes a list of the species cited in this three-part series.

Biological Assay↗
PubMed1991

Uses and bioassays in Phyllanthus (Euphorbiaceae): a compilation. II. The subgenus Phyllanthus.

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published in four parts, including (Part IV) analysis, discussion and conclusions concerning apparent clustering of some uses or effects within taxa. This paper (Part II) covers the subgenus Phyllanthus.

Humans↗
PubMed1991

Characteristics of hepatitis B X antigen, antibodies to X antigen, and antibodies to the viral polymerase during hepatitis B virus infection.

The characteristics of hepatitis B virus (HBV) X antigen (HBxAg) and antibodies against the X antigen (anti-HBx) and the viral polymerase (anti-pol) were determined in 85 HBV-infected patients. HBxAg was detected in sera positive for HBV e antigen (HBeAg) and HBV DNA in patients with acute and chronic hepatitis, while anti-HBx appeared when markers of viral replication became undetectable. HBxAg was common in the liver among patients with chronic hepatitis independent of HBV replication markers but was closely correlated with elevated alanine aminotransferase, implying that HBxAg in liver may be important in the pathogenesis of chronic infection. Anti-pol was detected in many samples positive for HBeAg and HBV DNA and less often in serum samples without markers of HBV replication, suggesting that this marker could reflect ongoing viral replication in the liver, even though such markers were absent from sera.

Acute Disease↗
PubMed1979

Sex differences in response to hepatitis B virus. I. History.

Sex differences related to responses to hepatitis B infection are reviewed. In most human populations there is a higher prevalence of chronic carriers of hepatitis B virus (persistently HBsAg+) among males than females. Females are more likely than males to produce anti-HBs in response to infection. Diseases associated with increased frequencies of carriers are more prevalent among males. The response of parents to hepatitis B virus (HBV) infection appears to affect the sex ratio at birth of their offspring. Couples in which either parent is a carrier have higher sex ratios (higher proportion of males) compared with couples in which neither parent is HBsAg+. Couples in which the mother is anti-HBs+ have children with lower sex ratios than either carriers or uninfected couples.

Carrier State↗
PubMed1979

Serum iron levels and response to hepatitis B virus.

Response to hepatitis B virus (HBV) infection [HBV surface antigen (HBsAg) and antibody to HBsAg (anti-HBs)], serum iron, total iron-binding capacity, hematological status (erythrocytes, Hb, and hematocrit), and evidence of liver damage (serum glutamic pyruvic transaminase; aspartate aminotransferase, L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) were determined for 201 patients on chronic renal dialysis. Four factors-serum iron level, transminase level, sex, and HBV response [i.e., infected-HBsAg(+) (HBsAg positive), anti-HBs(+) (anti-HBs positive), or no response]-were analyzed simultaneously to test the hypothesis that serum iron is higher in those with HBsAg in their serum than in those without HBsAg, independent of the transaminase level. Four independent, statistically significant two-factor interactions were identified. (i) Serum iron is higher in those HBsAg(+). (ii) Serum iron is higher in those with increased transaminase. (iii) Transaminase is higher in those HBsAg(+). (iv) Males are more likely to be HbsAg(+) and females are more likely to be anti-HBs(+). Also, those who are HBsAg(+) have significantly higher percent iron saturation (serum iron/total iron-binding capacity). That is, the hypothesis was supported by the findings. Several additional biological hypotheses are suggested, including a possible role of increased iron levels in susceptibility and response to HBV infection and the possible relationship between higher iron levels and the likelihood of HBV infection progressing to primary hepatocellular carcinoma. In addition, further tests of the initial hypothesis in nonhospitalized populations with endemic HBV infection are proposed.

Alanine Transaminase↗
PubMed1978

Distribution of albumin variants Naskapi amd Mexico among Aleuts, Frobisher Bay Eskimos, and Micmac, Naskapi, Mohawk, Omaha, and Apache Indians.

In order to help define the boundaries of the distribution of the albumin variants Naskapi and Mexico which are polymorphic among several American Indian groups, we examined sera from Micmac, Mohawk, Northwest River Naskapi, Omaha and Apache Indians, and from Aleuts and Eskimos. Sera from a total of 1,524 individuals were examined. Using a cellulose acetate membrane electrophoretic system with Tris-Citric acid at pH 5.4 we were able to distinguish normal albumin and both variants in the same run. Naskapi and Mexico variants were absent from Aleut, Eskimo, Micmac, Mohawk and Omaha samples. The albumin Naskapi variant was present in an allele frequency of 0.03 in the Naskapi Indian sample. Albumin variants Naskapi and Mexico were found in the Apache sample at frequencies of 0.016 and 0.037, respectively. This report supersedes that previously published by Schell and Agarwal ('76). Generally, within an area there is a correspondence between changes in the frequency of albumin variants and changes in the ethnic background and history of the area's populations. At the same time, when viewing widely separated areas, relationships between distant groups based on linguistic and cultural similarities are paralleled on a biologic level by the distribution of normal albumin and variant albumins.

Alleles↗
PubMed1978

e Antigen in hepatitis B virus infected dialysis patients: assessment of its prognostic value.

Many investigations consider the presence of e antigen (HBeAg) valuable in predicting which patients with acute hepatitis B are at risk of remaining infected and developing chronic liver disease. We tested this hypothesis in a retrospective study of serial samples from patients undergoing long-term hemodialysis. We found HBeAg in the early phase of all hepatitis B virus (HBV) infections. There was no significant difference between transiently and persistently hepatitis B surface antigen (HBsAg)-positive persons with regard to the frequency of HBeAg during the first 3 months of HBs antigenemia. Thus during the early period of viral activity, the presence of HBeAg is of no prognostic values in determining chronicity of HBV infection. We believe the disagreement on the prognostic value of HBeAg is a reflection of variations in time and frequency of sampling. The HBeAg remains, however, a useful indicator of potential infectivity of HBsAg(+)persons.

Chronic Disease↗
PubMed1977

Hepatitis-B virus in bedbugs (Cimex hemipterus) from Senegal.

Bedbugs of the species Cimex hemipterus (F) were collected on four separate occasions from the bedding in the huts of village dwellers in Senegal, West Africa. Hepatitis-B surface antigen (HBSAg) was detected in unengorged nymph and adult bedbugs in each of the first three collections. 3 of 28 such specimens were HBSAg(+) in the first collection and 3 of 17 specimens were positive in the second collection. In the third, 6 of 9 were HBSAg(+) when the bed occupant was known to be HBSAg(+). 2 of these 6 positive insects did not contain human serum proteins. Bedbugs in the fourth collection were captured and kept alive without a blood meal for 30 days. 3 of 89 of these samples were HBSAg(+). These are the highest field infection-rates of hepatitis-B virus reported in any insect species. The bedbug must be considered a potential vector of hepatitis-B virus.

Adolescent↗
PubMed1977

Association of graft survival with host response to hepatitis B infection in patients with kidney transplants.

We studied the relation of host response to hepatitis B infection before transplantation with survival of kidney grafts in 79 patients receiving 87 transplants. Antibody to hepatitis B surface antigen (anti-HBs) signaled early graft rejection (median survival congruent to two months), whereas hepatitis B surface antigen (HBsAg) signaled delayed rejection (greater than 22 months). Patients with neither HBsAg nor anti-HBs had graft survival times (median congruent to 16 months) similar to the HBsAg carriers but significantly longer than the anti-HBs-positive patients (p less than 0.01). Similar results were observed when patients who received HLA-identical kidneys or had anti-HLA antibodies before transplantation were excluded. The highest probability of graft rejection was in patients with anti-HBs who received kidneys from male donors. The probability that such grafts would survive for four months was less than 20 per cent. HLA-nonidentical kidneys transplanted into patients with anti-HBs have a poor prognosis, whereas such grafts in HBsAg carriers have as good a prognosis as grafts in uninfected recipients.

Antibodies, Viral↗
PubMed1977

Neutrophil function in children who are carriers of hepatitis-B surface antigen.

The functional capacity of neutrophils of twenty children who are chronic carriers of hepatitis-B surface antigen (HBsAg) was investigated by histochemical and quantitative nitroblue tetrazolium tests (N.B.T.), an assay of bactericidal capacity against Encherichia coli, and an immunofluorescence test for HBsAg in neutrophils, The histochemical N.B.T. test showed that there was a higher proportion of stimulated neutrophils in chronic HBsAg carriers than in controls, but HBsAg particles were not detected in these cells. Bactericidal activity was significantly reduced in chronic carriers. If the defects in neutrophil function in the HBsAg carrier children preceded their hepatitis-B infections they could have influenced the development of the carrier state. Newborn infants infected with hepatitis-B virus are likely to become chronic carriers and neutrophil functions in uninfected newborn infants are similar to those seen in these carriers of HBsAg.

Adolescent↗
PubMed1977

Host responses to hepatitis B infection in patients in a chronic hemodialysis unit.

Host responses to hepatitis B infection were studied in 222 patients in a chronic hemodialysis unit. From 1970 to 1976, patients were monitored monthly for development of hepatitis B surface antigen (HBsAg), antibody to hepatitis B surface antigen (anti-HBs), and serum transaminase (SGPT) elevations. Five categories of patients were identified as: 1) chronic carriers of HBsAg; 2) transiently HBsAg(+), who developed anti-HBs; 3) HBsAg(-) on admission, who developed anti-HBs without becoming HBsAg(+); 4) anti-HBs(+) on admission; 5) uninfected who remained HBsAg(-) and anti-HBs(-). For a patient who became HBsAg(+) in this clinic, the probability of becoming a chronic carrier was 62-8% and rose to 88.5% if he or she had been HBsAg(+) for five consecutive months. Males were more likely to become chronic carriers, and females were more likely to develop anti-HBs. Neither age, race, nor type of underlying kidney disease was associated with particular host responses to hepatitis B virus. No effect of hepatitis B infection on mortality was detected. Variation in host response to hepatitis B infection among renal dialysis patients may affect the usefulness of hepatitis B hyperimmune globulin and hepatitis B vaccine and be related to the outcome of kidney transplantation.

Antibodies, Viral↗