Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The CD4 (or T4) surface antigen of human T lymphocytes is an important part of the receptor for the human immunodeficiency virus (HIV). After binding to the receptor, the HIV may enter the T cell and induce the formation of syncytia. In an attempt to identify the receptor site more closely, monoclonal antibodies (Mab's) to CD4 were tested for their ability to block HIV infection in a syncytium formation assay, and the CD4 epitopes so identified were mapped by antibody cross-blocking. The antibodies that showed strong inhibition of HIV fell into two main families while a third group of Mab's blocked syncytia formation weakly or not at all. Several different isolates of HIV as well as the laboratory strain CBL1 grown in CEM cells were used to induce the syncytia. The data indicate that only some epitopes of CD4 are important for virus binding and imply that the virus-binding site for CD4 is conserved in different isolates of HIV with substantially divergent env gene sequences. Preliminary studies of patients suggest that polymorphism of these epitopes does not play a role in determining susceptibility to infection.
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PMID:Epitopes of the CD4 antigen and HIV infection. 243 Mar 33

Although hepatitis B infection is endemic in southern Africa, a changing epidemiology of the disease has recently been documented in the region. The authors surveyed migrant southern African male mineworkers during 1986 to establish the prevalence of chronic hepatitis B and D (delta) infection in their areas of origin. Hepatitis B surface antigen (HBsAg) was tested in 29,312 adult male mineworkers from 18 geographic regions, encompassing the diverse tribal and linguistic groups in the region, as well as in expatriate mineworkers from neighboring southern African countries. The same cohort was also tested for antibody to human immunodeficiency virus (HIV). Selected hepatitis B carriers were also tested for hepatitis B virus deoxyribonucleic acid (DNA), antibody to hepatitis D (anti-HD), and alpha-fetoprotein. The overall prevalence of HBsAg in this survey was 9.9%. However, the prevalence varied from 5.5% to 14% in different ethnic groups. A minority of carriers (4.9%) had replicative hepatitis B infection and were hepatitis B virus DNA-positive. Only 0.6% of tested carriers were anti-HD-positive. Alpha-fetoprotein determinations were abnormal in 1.2% of hepatitis B-positive men. These data show that although chronic hepatitis B infection remains widespread in southern Africa, carrier rates vary significantly from region to region. In contrast, hepatitis D co-infection remains extremely uncommon. These baseline seroprevalence data also establish that HIV infection was, in 1986, a rare infection in the indigenous population of South Africa.
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PMID:Regional prevalence of hepatitis B, delta, and human immunodeficiency virus infection in southern Africa: a large population survey. 246 88

To evaluate the prevalence of hepatitis virus markers and human T-cell lymphotropic virus infections among drug abusers in Japan, serum samples were collected from 91 male drug abusers at the Shinshu University Hospital and the rehabilitation facility in Matsumoto and from 519 healthy male blood donors as controls. Sera were tested for antibody to hepatitis A virus (anti-HAV), hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), antibody to hepatitis B core antigen (anti-HBc), immunoglobulin M anti-HBc (IgM anti-HBc), antibody to hepatitis D virus (anti-HDV), antibody to HTLV type 1 (anti-HTLV 1), and antibody to human immunodeficiency virus (anti-HIV). The prevalence of anti-HAV was 13.2% in drug abusers and 10.8% in controls (not significant). The prevalences of HBsAg, anti-HBs, anti-HBc and exposure rate to hepatitis B virus (HBV) were 4.4%, 24.2%, 31.9%, and 35.2%, respectively, in drug abusers and 0.8%, 6.7%, 9.6%, and 9.6% in controls. The exposure rate to HBV was significantly different (P less than 0.001). IgM anti-HBc and anti-HDV were not detected in any sera. Anti-HTLV I was detected in three drug abusers (3.3%) and in one (0.2%) of the controls (P less than 0.01). All sera were negative for anti-HIV in all subjects. Infection with HBV and HTLV I is more common among drug abusers than in the general population of blood donors in Japan.
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PMID:Seroepidemiology of hepatitis A, B, and D viruses and human T-lymphocyte tropic viruses in Japanese drug abusers. 255 57

The ultrastructural alterations induced by human immunodeficiency virus (HIV) in human lymphoid cells have been evaluated. Electron microscopic examination of peripheral blood mononuclear cells (PBMC) from 14 male homosexuals with confirmed acquired immunodeficiency syndrome (AIDS) or AIDS-related complex revealed that tubuloreticular inclusions were present in 5-15% of the cell sections from each case. In 5 of 14 cases, cylindrical confronting lamellae were found in 1-2% of the cell sections. No retrovirus-like particles or surface membrane alterations were detected. Neither of these structural alterations was observed in control PBMC obtained from six HIV-seronegative, hepatitis B virus surface antigen (HBsAg)-positive carriers or in 11 healthy subjects. When primary cultures of CD4+-enriched lymphocytes were infected in vitro with HIV, tubuloreticular inclusions could be detected in 3-10% of the cell sections, but no cylindrical confronting lamellae-like structures were found. In contrast, neither of these alterations were seen in uninfected or HIV-infected H9-HT continuous cell lines. These in vivo and in vitro studies indicate that there is an association between the appearance of the tubuloreticular inclusions and cytopathic HIV infection, although no correlation between cytopathic changes and active viral replication was observed at the single cell level. Further studies will be required to establish the mechanism(s) of formation of the tubuloreticular inclusions and to determine their prognostic potential.
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PMID:In vivo and in vitro ultrastructural alterations induced by human immunodeficiency virus in human lymphoid cells. 257 Jan 80

To determine the influence of concurrent human immunodeficiency virus (HIV) infection on chronic hepatitis B virus (HBV) infection, 150 male homosexual chronic hepatitis B surface antigen (HBsAg) carriers were studied. Of these, 82 subjects (55%) tested positive for antibodies to HIV. They were more likely to express hepatitis B "e" antigen (HBeAg) (P less than .001) and HBV-DNA (P less than .0005) in serum than were HIV-seronegative individuals. However, the degree of immune suppression did not influence HBeAg-HBV-DNA expression. In HBeAg-seropositive subjects, concurrent HIV infection was associated with lower serum alanine transferase levels (P less than .001). This effect increased with the degree of immune suppression as determined by CD4+ lymphocyte counts. Conversely, in patients negative for HBeAg, there was a weak trend towards higher alanine transferase levels with concurrent HIV. This study suggests that chronic hepatitis B may be less severe when accompanied by HIV infection; however, greater viral replication may make it more contagious and resistant to antiviral therapy. These data support an immune-mediated pathogenesis for hepatitis B and have implications for its control.
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PMID:The effect of concurrent human immunodeficiency virus infection on chronic hepatitis B: a study of 150 homosexual men. 257 46

Of a total number of 643 injured patients admitted during 1986 and 1987, 113 were tested for antibodies against the human immunodeficiency virus (HIV) and hepatitis B surface antigen HBsAg and the concentration of hepatitis B surface antibodies (HBsAb) was determined. Nine patients were HIV positive while HBsAg was detected in two patients and increased levels of HBsAb were found in 19 patients. HIV antibodies were found in 6 (4.8 per cent) of 124 victims of violence, in 3.3 per cent of the patients with penetrating injuries and 1.1 per cent of the patients with multiple, closed injuries. The estimated prevalence for HIV infection in the Norwegian population is 0.08 per cent, thus indicating an over-representation of infected patients among injured patients and victims of violence.
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PMID:Human immunodeficiency virus and hepatitis B virus in injured patients and victims of violence. 259 57

Hospital transfusion services and blood centers still use manual hemagglutination tests for most of their serological procedures. Automation of hemagglutination reactions has proven to be difficult, primarily because hemagglutination lacks an objective endpoint which can be easily interpreted by inexpensive instruments. Alternatively, solid-phase red cell adherence assays for ABO cell and serum grouping, Rh typing, red cell and platelet antibody screening, red cell and platelet crossmatching, IgA deficiency screening, hepatitis B surface antigen, and HIV antibody screening have been developed. The performance of these assays compares favorably with current hemagglutination and enzyme immunoassay methods. All of these tests share a common objective endpoint of adherence or nonadherence of indicator red cells. This uniformity allows easy interpretation of results visually, spectrophotometrically, or by image analysis. The latter technique has the potential to revolutionize the reading and interpretation of all agglutination tests. Solid-phase red cell adherence tests in microplates are ideal for batch processing large numbers of specimens. However, adherence tests are not restricted to this format. Therefore, blood grouping dipsticks have been produced, which permit testing of individual blood samples even outside of the laboratory.
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PMID:The evolution of pretransfusion testing: from agglutination to solid-phase red cell adherence tests. 265 94

A serological survey in Mauritania in 1985-86 provided data on certain viral and bacterial markers whose frequency has been well established in countries neighboring this gateway between North Africa and subSaharan Africa. Blood samples from 1230 male blood donors and 983 pregnant women at the hospital in Nouakchott were analyzed for treponema infection, hepatitis B, HIV, and for antibodies to certain viruses causing hemorrhagic fever. Positive results for treponema specific antibodies using the Kline reaction were obtained in 76 of 2213 serums examined. High positive rates in young age groups reflect endemic nonvenereal treponematosis. 16 of 218 persons aged 10-19 tested positive compared to 10 of 593 aged 30-39 and 2 of 133 aged over 40. Observed differences between ethnic groups were highly significant. Infection rates were higher among males except among the Poulars. A very high prevalence of hepatitis B markers was found with more than 20% of hepatitis B surface antigen carriers among the 766 samples studied. 88.68% of the 813 subjects studied had been infected with the hepatitis B virus. The results suggest that nomadism, or the hygienic conditions of nomadism, favor contamination by the hepatitis B virus. 3 of the 510 samples examined were positive for HIV. Only 1 of the positive samples was from a Mauritanian, a 28-year-old male Poular. The other 2 positive results were obtained from foreigners temporarily residing at Nouakchott. The prevalence of antibodies against the viruses responsible for hemorrhagic fever was very low: 1/965 for the Crimee-Congo, 2/965 for the Rift Valley fever virus, and 3/965 for the Hantaan virus.
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PMID:[Sero-epidemiological study in Mauritania (1985-1986): incidence of treponematosis, hepatitis B virus, HIV virus and viral hemorrhagic fevers]. 290 81

The presence of human immunodeficiency virus (HIV) antibody in hemophilia patients was correlated with the loss of existing antibody to hepatitis B surface antigen (HBsAb) or the inability to develop an antibody to hepatitis B after receiving commercially available hepatitis B vaccine. Of the 137 patients studied 66 were HIV-positive and 71 were HIV-negative. Evidence of HBsAb (n = 44) or exposure to hepatitis vaccine (n = 12) was found in 85% of HIV positive patients at some time during their care in our clinic. However, 20% demonstrated subsequent antibody loss and/or did not respond to hepatitis vaccine. Loss of HBsAb or vaccine nonresponse was restricted to patients less than 21 years of age (72% of all patients). This result contrasted to only a 3% loss of HBsAb or vaccine nonresponse in the HIV-negative patients who had acquired the HBsAb (n = 23) or were given the hepatitis vaccine (n = 29). This result suggests that loss or alterations of hepatitis B immunity occur in association with HIV infection or exposure.
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PMID:Loss of hepatitis B antibody in human immunodeficiency virus-positive hemophilia patients. 296 61

An automated pretransfusion testing system was applied to HIV antibody screening by a gelatin particle agglutination (HIV-PA) test. The test conditions for the test, such as diluent, plate shape, and incubation time, were applicable not only for the HIV-PA test but also for other routine tests, including those for hepatitis B surface antigen and HTLV-1 antibodies. After a 60-minute incubation, the plates were read automatically and then were assessed visually. Tests with seropositive samples obtained from hemophiliacs and an HIV enzyme immunoassay (EIA) familiarization panel showed that the automated HIV-PA test was more sensitive than the EIA and did not show a false-negative result. Of 11,300 blood donors, 44 were positive by the automated test, and 51 were positive by the EIA. None of the blood donors was confirmed to be seropositive. Using the automated test, a large number of samples could be screened in a relatively short time without a significant increase of nonspecific reactions.
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PMID:An automated screening test for antibodies to human immunodeficiency virus-1. 305 84


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