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)

Transfusion of whole blood or blood components is the mainstay of treatment in patients with beta-thalassemia and hemophilia. Owing to the scarcity of reports regarding the frequency of transfusion-transmitted hepatitis virus infections in thalassemia patients, the frequency of such infections was studied in India in 40 multi-transfused thalassemia patients (26 males, 14 females; mean age 8.1 +or- 5.3 years, range 1-35) with no clinical or biochemical evidence of liver disease. The enzyme-linked immunosorbent assay (ELISA) technique (Abbott) was used for all tests. The patients had received an average of 80 units (range 10-250) of blood. A majority of these units had been screened for hepatitis B surface antigen (HBsAg) using RPHA. HBsAg antibodies were present in 18 (45%), antihepatitis C virus (HCV) in 7 (17.5%), and antihuman immunodeficiency virus in 1 (2.5%) case, respectively. Of 18 HBsAg positive patients, antidelta and anti-HCV antibodies were present in 3 and 4 patients, respectively; 1 patient had both the antibodies. 4 of 40 (10%) patients had evidence of both hepatitis B virus (HBV) and HCV infection. In a US study, the frequencies of HBsAg and anti-HBs positively among thalassemics were 4.5% and 43.5%, respectively. In contrast, 90% of hemophiliacs show serological evidence of HBV infection. Routine screening of blood donors by CEP or RPHA technique was started in the hospital blood bank 7 years ago. The sensitivity of these techniques is much lower than that of RIA and ELISA and a majority of the patients has received initial blood transfusions before HBsAg screening was started. The study indicated that more than 50% of multi-transfused thalassemia patients showed serological evidence of one or more HBV, HCV, HDV, and HIV infection. Thus, screening of blood units for HBV, HCV, and HIV infections to be used for thalassemic patients and vaccination of thalassemic patients against hepatitis B is imperative.
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PMID:Frequency of hepatitis B, C and D and human immunodeficiency virus infections in multi-transfused thalassemics. 142 37

Several 2',3'-dideoxynucleosides (ddNs), agents that inhibit the replication of human immunodeficiency virus and hepatitis B virus, enter mammalian cells by simple diffusion. In this report, we show that the membrane permeation of 2',3'-dideoxyguanosine (ddG) in human erythrocytes and CCRF-CEM cells, in contrast with that of other ddNs, is transporter-mediated. Inward fluxes of ddG in both cell types were inhibited by adenine, hypoxanthine, and acyclovir, but not by inhibitors of nucleoside transport (nitrobenzylthioinosine, dipyridamole, dilazep). Fluxes of ddG in human erythrocytes were attributable to a single, rate-saturable process (Km, 380 +/- 90 microM and Vmax, 7.9 +/- 0.8 pmol/s/microliter cell water) that was competitively inhibited by adenine (Ki, 16 microM). These results showed that ddG entered human erythrocytes and CCRF-CEM cells by a transporter-mediated process that was also the basis for entry of purine nucleobases. In contrast, inward fluxes of 2,6-diaminopurine-2',3'-dideoxyriboside (ddDAPR), a prodrug of ddG, were not affected by purine nucleobases or nucleoside transport inhibitors in either cell type. Thus, the permeation properties of ddDAPR resembled those of 2',3'-dideoxyadenosine, a diffusional permeant (cell uptake is transporter-independent), and contrasted with those of ddG, the deamination product of ddDAPR. This study demonstrated that the nucleobase moiety of ddNs is an important determinant of membrane permeation.
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PMID:Nucleobase transporter-mediated permeation of 2',3'-dideoxyguanosine in human erythrocytes and human T-lymphoblastoid CCRF-CEM cells. 142 79

On the basis of published sequence data the preS1 attachment region of hepatitis B virus (HBV) appears to be highly variable. Using a novel method for rapid DNA sequencing by the polymerase chain reaction we screened 34 HBV DNA-positive sera for mutations in a variable part of the preS1 region of the HBV genome. The sequence data were used to analyse potential chains of infection, and strongly supported the expected routes of HBV transmission among patient groups. Furthermore, sequence comparisons permitted sub-genotyping of the viruses. In the 22 cases of subtype adw, we found a very low number of point mutations. This shows that the attachment site of HBV is more highly conserved than that of other blood-transmissible viruses such as human immunodeficiency virus or hepatitis C virus.
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PMID:Genomic variability in the preS1 region and determination of routes of transmission of hepatitis B virus. 143 14

The role of sexual transmission of hepatitis C virus in Black South Africans was evaluated by a seroprevalence study of sentinel populations at varying risk for sexually transmitted diseases (STD). Prevalence of anti-hepatitis C virus antibodies was found to be 1.8% in an STD clinic sample of 272, 0.7% in a family planning sample of 148, 3.3% in a sample of 246 'blue collar' workers (81% of rural origin), and 0.9 in a sample of 117 new blood donors. All samples were from Black adults. The differences between them were not significant (P = 0.2348). In contrast, the prevalence of anti-human immunodeficiency virus antibodies in the STD sample (5.5%) was statistically significantly different (P = 0.00095) from the family planning clinic sample (1.4%) and the blue collar sample (0.8%) as well as from the reported prevalence for black blood donors in the Johannesburg area (0.7%). No evidence supporting a role for sexual transmission of hepatitis C virus was found, while the prevalence of infection appeared to be higher in rural populations and in males. These features are similar to hepatitis B in this population.
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PMID:The role of sexual transmission in the epidemiology of hepatitis C virus in black South Africans. 144 Aug 27

Trends in mortality related to infection by human immunodeficiency virus type 1 (HIV-1) and to other causes were examined from 1978 to 1988 in a cohort of 8,906 homosexual men who participated in studies of hepatitis B virus infection in the late 1970s in New York City. HIV-related mortality rates increased from 1 per 10,000 person-years in 1980 to 181 per 10,000 person-years in 1986, followed by a plateau from 1986 to 1988. The standardized mortality ratio among white men in the cohort was 3.7 (95% confidence interval (Cl) 3.4-3.9) as compared with white men from across the United States. Higher HIV-related mortality rates were associated with a higher number of sexual partners, a history of gonorrhea and/or syphilis, and serologic markers of infection with hepatitis B virus. After adjustment for demographics and sexual behaviors, the relative risk of mortality for Hispanic men as compared with white men was 1.5 (95% Cl 1.1-1.9). This study illustrates the large excess in mortality among homosexual men over the last decade, with the excess accounted for by deaths from HIV-related diseases. The recent plateau in mortality may be due to the effect of new treatments and/or the decline in new HIV-1 infections among homosexual men. The excess in HIV-related mortality among Hispanic homosexual men was not explained by differences in demographics and factors associated with the sexual transmission of HIV-1.
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PMID:Mortality trends in a cohort of homosexual men in New York City, 1978-1988. 144 31

Eighteen human immunodeficiency virus (HIV) vertically infected children (HIV group) and 33 seroreverted children (SR group), who had completed hepatitis B vaccination (Engerix B, 20 micrograms dose) were studied. Four out of 18 (22%) HIV children failed to develop protective antibody levels (anti-HBs titres less than 10 mIU ml-1) compared with 1 out of 33 (3%) SR children (p less than 0.05). Magnitude of response among HIV children was significantly lower than among SR children. In HIV children the probability that anti-HBs titres persist above the protective levels was significantly lower than in the SR group at any time during the 24 month follow-up. These results show that HIV children have a suboptimal response to hepatitis B immunization and the protection is less durable. Further studies are needed to determine the optimal protocol for hepatitis B immunization in HIV children.
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PMID:Impaired response to hepatitis B vaccine in HIV infected children. 145 11

The association of malignancies, such as non-Hodgkin's lymphoma and Kaposi's sarcoma, with human immunodeficiency virus infection has been recognized since the beginning of the epidemic. However, an increasing number of tumors not diagnostic of acquired immunodeficiency syndrome has been described in this setting. Taking into consideration that survival of patients with human immunodeficiency virus infection is increasing because of improvement of supportive care and better control of human immunodeficiency virus and related opportunistic infections, oncogenic viruses such as human papillomavirus, hepatitis B virus, Epstein-Barr virus, in a setting of prolonged immunosuppression could increase the risk of a variety of malignant tumors.
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PMID:Human immunodeficiency virus as a risk factor in miscellaneous cancers. 145 6

The molecular characteristics of peripheral blood lymphocyte (PBL) infection by hepatitis B virus (HBV) were studied in human immunodeficiency virus type 1 (HIV-1) infected subjects using highly sensitive polymerase chain reaction (PCR) based techniques. DNA and RNA samples were purified from PBLs of HIV-1 infected individuals, regardless of their HBV serological status and assayed using PCR and reverse-transcription (RT) PCR, respectively. The data shown here are an extension of previous reports documenting HBV and HIV-1 co-infection of PBLs and indicate that transcriptionally active HBV infection of PBLs is detectable in a significant proportion of asymptomatic HIV-1 infected patients.
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PMID:Human immunodeficiency virus type 1 and hepatitis B virus transcription in peripheral blood lymphocytes from co-infected subjects. 152 92

We studied the immunogenicity of the standard schedule of recombinant hepatitis B vaccine (20 micrograms per dose at months 0, 1, and 6) in 21 anti-human immunodeficiency virus (HIV)-positive persons. Relatively low titers of anti-HBs developed in only five subjects (23.8%) 1 month after the third dose; all five had T4 cell counts greater than 700 cells/mm and none of the 11 subjects with a T4 cell count below this value responded. Five of the 16 nonresponders to the vaccine later had acquired immunodeficiency syndrome (AIDS)-related complex (two) and AIDS (three), while none of the responders did. Our results show that anti-HIV-positive persons are poor responders to the recombinant hepatitis B vaccine, and that the absence of a response is an indicator of a more severe immune deficiency and of a poor prognosis. An optimal regimen of hepatitis B vaccination in HIV-infected persons is still to be established.
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PMID:Impaired response to recombinant hepatitis B vaccine in HIV-infected persons. 153 9

We postulated that three factors determined the occupational risk of infection from the human immunodeficiency virus (HIV) for surgeons, anesthesiologists, and medical students: first, the risk of needlestick exposure per year (range for surgeons 3.8-6.2, weighted average 4.2; range for anesthesiologists 0.86-2.5, weighted average 1.3; range for third-year medical students 0-5, best estimate 5); second, the risk of seroconversion from a needlestick exposure (0.42%-0.50%); and third, prevalence of HIV in the population served (0.32%-23.6%, depending on geographic location). Thus, the calculated range for occupational risk of HIV infection for a surgeon over a 30-yr period (assuming no change in HIV prevalence or benefit from protective measures) was 0.17%-13.9%; for an anesthesiologist, 0.05%-4.50%. The corresponding range of occupational risk for a medical student during the third year was 0.007%-0.59%. The range of risk is large because the variation in prevalence of HIV infection from one area to another is great. The authors validated the methodology first by using an equation, with estimates from the literature for factors in the equation, to calculate the risk of infection for hepatitis B and then by comparing the results with known rates of infection in the prevaccine era. Calculated occupational risk of hepatitis B infection for anesthesiologists was in the lower range of actual prevalence of infection (calculated range 2.32%-20.6%; known range 6%-26%). Calculated risk versus prevalence for surgeons was fairly close (7.31%-53.4% versus 24.4%).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Risk of human immunodeficiency virus in surgeons, anesthesiologists, and medical students. 846 52


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