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)

Zidovudine or 3'-azido-2'-3'-dideoxy-thymidine (AZT) is an antiviral drug widely used to treat HIV-infected patients. Because cytotoxic T lymphocytes (CTL) are thought to contribute actively to resistance against HIV-induced disease, we studied sequentially 10 HIV-infected individuals under zidovudine treatment for a period of 6-12 months. For a given patient all lymphocyte suspensions corresponding to the complete zidovudine therapy period were tested on the same day and on the same target cells. Patients were selected for expression of HLA-A2 and/or HLA-A3 class I transplantation antigen. HLA-restricted cytotoxicity specific for env, gag and nef HIV proteins was quantified for each patient at 6 week intervals. The data clearly indicated that zidovudine has a beneficial effect on the CTL response during the first 6-12 weeks of treatment, inducing cytotoxicity levels up to 100-fold stronger than base line. This effect was usually short lived. However, patients who maintained strong levels of cytotoxicity had better clinical and survival outlook than patients who had lost all detectable cytotoxic lymphocytes. It is proposed that AZT, among other effects, delays the onset of disease in HIV-infected patients by contributing to the stimulation of the HIV-specific CTL response.
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PMID:Enhancement of HIV-specific cytotoxic T lymphocyte responses by zidovudine (AZT) treatment. 173 39

To further study the possibility of transmission of HIV infection by close personal but non-sexual, non-parenteral contact we have continued to enroll and evaluate household contacts of adult patients with AIDS. Two hundred and six household contacts of 90 patients with AIDS were evaluated with detailed interviews, physical examinations, and detection of HIV antibodies and p24 antigen from 1984 to 1987; 118 of these contacts were re-evaluated 6-12 months after cessation of household contact or death of the patient. The median duration of household contact from 18 months prior to symptoms in the AIDS patients to last contact was 23 months (range 3-101 months). The median time elapsed from first contact during this period to the last evaluation was 38 months (range 13-66 months). No household contact had signs or symptoms suggesting HIV infection. All 206 were negative for serum antibodies to HIV and HIV p24 antigen, despite extensive sharing of household facilities and items and personal interactions with AIDS patients. This study continues to show that household members without other risks remain at minimal to no risk for HIV transmission (95% confidence interval, 0-1.44) despite prolonged and substantial close non-sexual contact with AIDS patients, and after re-evaluation at a median of 10.9 months after initial evaluation.
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PMID:Additional evidence for lack of transmission of HIV infection by close interpersonal (casual) contact. 211 67

Prevalence and determinants for human immunodeficiency (HIV) virus infection was assessed in 581 heterosexual intravenous drug users, recruited from public drug assistance centers in the northeast of Italy between 1984 and 1988. The overall seroprevalence rate for HIV antibody was 39% (95% confidence interval-CI-35-43%). HIV prevalence had risen from 32% in 1984-85 to 47% in 1986-88. Age was not associated with HIV infection risk, whereas gender was, women being at lower risk of infection than men (odds ratio-OR- = 0.7, 95% CI: 0,5-1.0). Seropositivity rates showed a strong east-west geographical gradient: intravenous drug users living in the western part of the study area had a nearly sevenfold higher risk of infection (95% CI = 4.4-13.9) than those living in the eastern part. Sharing of drug injection equipment was by far the most important risk factor. IVDUs who reported to always share injection equipment had a fourfold higher risk of HIV infection, as compared with those who never did (95% CI = 1.6-12.7). The duration of drug addiction (odds ratio = 2.6), the use of heroin in high-incidence cities (odds ratio = 2.3) and of cocaine in addition to heroin (odds ratio = 1.5) and the practice of prostitution (odds ratio = 2.3) were also important determinants of HIV infection. Over the study period, the odds ratios associated with area of residence decreased, whereas those associated with the use of heroin in high-incidence cities and with prostitution increased.
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PMID:[Prevalence and determinants of HIV infection in 581 drug addicts in the Northeastern Italy, from 1984 to 1988]. 215 22

A total of 228 stored serum samples from 140 high risk individuals was examined for serological markers of human immunodeficiency virus (HIV) infection by second generation enzyme-linked immunosorbent assay, immunoblot, and HIV antigen assay. All the samples were negative in first generation enzyme-linked immunoassay (ELISA). Seventy-four of the serum samples had been obtained from 40 sexual partners of HIV antibody positive individuals. Two of the samples were reactive for p24 in immunoblot, but no other markers of HIV infection were found. From 80 sexually active male homosexuals, 117 serum samples were obtained. They were all negative by the tests employed. Further, 37 serum samples from 20 seroconverters were studied. Four patients had antigenaemia 6-12 months before seroconversion was detected by first generation ELISA. Our data do not support the notion that serological signs of HIV infection are common in high risk individuals seronegative by first generation ELISA. However, HIV infection do occur in subjects negative by first generation ELISA, which emphasises the need for more sensitive screening assays and/or the use of antigen detection as part of screening in high risk individuals. The advent of second generation ELISAs has not in a substantial way reduced this demand.
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PMID:Markers of human immunodeficiency virus infection in high-risk individuals seronegative by first generation enzyme-linked immunosorbent assay. 250 48

Serum antibody reactive with epitopes within the CD4 binding site (CD4BS) of HIV-1/gp120 on infected cells was measured by inhibition of binding of a human monoclonal antibody, F105, which recognizes a conformational epitope within this region. Serum samples from 27% of ARC/AIDS patients blocked binding of F105 to this epitope, while samples from 100% of asymptomatic seropositive patients blocked binding. F105 blocking activity increased in 87% of asymptomatic donors who maintained stable disease over a 3-6 year period and decreased in 50% of asymptomatic patients with progressive disease. Moreover, serum samples from patients with stable disease exhibited higher titers of F105 blocking activity. The presence of F105 blocking activity also correlated with serum neutralization of virus. When diluted 1:640, serum with low F105 blocking activity neutralized only 20-30% of viral cytopathic effect (CPE), while serum with high F105 blocking activity neutralized > 80%. Serum neutralization was enhanced by the addition of F105. Seroreactivity to infected cells was detectable within 6 months of seroconversion, but F105 blocking activity was delayed by an additional 6-12 months, as was the development of high titers of neutralizing antibody. These data support the notion that the humoral response to the CD4BS on gp120 may be important in the maintenance of health.
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PMID:Loss of serum antibodies to a conformational epitope of HIV-1/gp120 identified by a human monoclonal antibody is associated with disease progression. 769 37

How many more potential and actual workdays are lost by HIV patients than persons without HIV? To answer this question, we assessed differences in the number of workdays among a panel of AIDS patients, patients who were HIV positive but did not yet have AIDS, and comparison patients. The patients included persons who were employed and unemployed. Information on 1,346 patients was gathered from January 1, 1990, to December 31, 1992, as part of the ongoing ATHOS (AIDS Time-Oriented Health Outcome Study) study. Data were collected every 3 months on AIDS and HIV-positive patients and every 6-12 months on the comparison patients. At the end of the study (December 31, 1992), 856 people were still enrolled. A total of 5,507 panel data points covering 3 years were available. Data were analyzed with a linear regression model. We found that patients with AIDS reported 29-32 and HIV-positive patients reported 9-13 more potential and actual workdays lost out of the previous 90 than the comparison patients, other variables being equal. All p values were < 0.005, and most were < 0.0001. We conclude that (a) while the AIDS patients showed substantially more workdays lost than the comparison group, the HIV-positive group showed only a modest number of more days lost than the comparison group and (b) that previous estimates exaggerated indirect morbidity costs.
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PMID:Potential and actual workdays lost among patients with HIV. 788 5

Human immunodeficiency virus 1-related idiopathic thrombocytopenic purpura (HIV-1-ITP) patients have a 4-fold increased percentage of CD5+ B cells and a 4.8-fold increased percentage of serum immune complexes precipitated by polyethylene glycol (PEG-ICs) compared to control subjects, as reported previously. Since CD5+ B cells produce predominantly IgM rheumatoid factor (RF) vs. Fc of IgG and PEG-ICs contain high levels of IgM, we looked for the presence of RF in the immune complexes of HIV-1-ITP patients. PEG-ICs were adsorbed to protein A and dissociated with acid, and IgM and IgG were purified by gel filtration and affinity chromatography. Solid-phase ELISA was used to measure antibody specificity vs. platelets, Fc, and HIV-1 gp120, p24, and CD4. Dissociated IgG antibody reacted with platelets, HIV-1 gp120, p24, and CD4, but not with Fc. Serum IgG did not react with platelets or Fc but did react with HIV-1 gp120, p24, and CD4. Both PEG-IC IgM and serum IgM reacted with Fc as well as the other four antigens. Control IgM and IgG were unreactive. Isolated IgM from PEG-ICs relocated approximately 50% of the IgG preincubated with IgM to the Vo region of a G200 gel-filtration column. Anti-platelet IgG but not IgM could be affinity-purified from fixed platelets. Both F(ab')2 fragments of anti-platelet IgG and the total PEG-IC bound to platelets in a saturation-dependent manner. F(ab')2 of anti-platelet IgG inhibited 50% binding of PEG-IC to platelets at an F(ab')2/complex ratio of 3:1 (wt/wt). Scatchard analysis revealed two classes of binding sites: high-affinity Kd values of 0.8-1.8 nM and lower-affinity Kd values of 6.6-12.3 nM with respective numbers of binding sites of 44,000-57,000 and 122,000-256,000 (n = 4). Anti-platelet IgG of 6/6 patients precipitated GPIIIa from platelet lysates of surface 125I-labeled platelets. Platelet count correlated inversely with anti-platelet IgG (r = -0.73; P < 0.01; n = 27). Thus, PEG-ICs of HIV-1-ITP patients contain IgM RF, which sequesters serum anti-platelet IgG containing anti-GPIIIa. Anti-platelet IgG contributes to binding of immune complexes to platelets and correlates with thrombocytopenia.
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PMID:Sequestration of anti-platelet GPIIIa antibody in rheumatoid factor immune complexes of human immunodeficiency virus 1 thrombocytopenic patients. 789 59

To approximate the contributions of in utero, intrapartum, and postnatal transmission of human immunodeficiency virus type-1 (HIV-1) and to evaluate polymerase chain reaction (PCR) as a diagnostic tool for pediatric HIV infection, blood was collected at birth (cord blood), and at 3, 6-12, and 13-24 months in 218 children born to HIV-1-seropositive mothers in Kigali, Rwanda. Proviral DNA was detected by a double PCR using two sets of three primers (gag, pol, and env). Pediatric HIV-1 infection was defined according to serological and clinical criteria. The probability of having a positive PCR at a given time was calculated by a nonparametric method. Among children with unequivocal evidence of infection (n = 47), it was 30.5% on cord blood and 80.6% at 3 months. Thus, in children born to HIV-1-infected mothers, the estimated rate of transmission in the late postnatal period is 4.9%, and the rate of transmission in the intrapartum plus postnatal periods is 17.6%. Among 117 HIV-1-uninfected children born to HIV-1-infected mothers, six (5%) had a false-positive PCR on cord blood. These results should be taken into account in designing intervention trials aimed at reducing mother-to-child transmission of HIV-1.
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PMID:An assessment of the timing of mother-to-child transmission of human immunodeficiency virus type 1 by means of polymerase chain reaction. 805 21

Concentration of neopterin (NPT) was measured in 3-6 months intervals in the serum of HIV-infected drug users taking continuously intravenous drugs and those who stopped the habit (MONAR, ZOZ). After 6-12 months of observation the mean NPT concentration was higher in the active drug users what was statistically essential. The outcome of our study indicates that current state of the patient concerning taking of drugs must be taken under consideration when NPT concentration is assessed as marker of progression of HIV disease.
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PMID:[Levels of neopterin in serum of narcotics abusers infected with human immunodeficiency virus (HIV)]. 808 13

During February-November 1991 in Abidjan, the Ivory Coast, interviews with 1257 male first-time blood donors and screening of their blood for antibodies to HIV-1 and HIV-2 were conducted at the National Blood Transfusion Center to determine whether it is feasible to exclude or defer donors at high risk of HIV infection. 143 (11.4%) men had antibodies to HIV. The multivariate analysis showed that the strongest risk factor for HIV infection was sex with prostitutes in the last 5 years without regular condom use (odds ratio [OR] = 10, confidence interval [CI] = 6.6-15) followed by prostitute contact in the last 5 years regardless of condom use (OR = 8.4, CI = 5.6-12.6), and an age of 30-39 years (OR = 6.9, CI = 18). 27% of all donors with prostitute contact in the last 5 years were infected (positive predictive value). If the center had used prostitute contact in the last 5 years as a criterion, it would have discarded 31% of all units of blood. Thus, more than 75% of all potentially excluded units would have been from donors infected with HIV. The sensitivity, specificity, and positive predictive values ranged from 15% to 98%, 38% to 91%, and 17% to 30%, respectively. These findings suggest that it is feasible in Abidjan to exclude donors based on behavioral characteristics of those most at risk of HIV infection. Donor deferral should be evaluated as a strategy to improve blood safety in resource-poor areas with high rates of HIV infection.
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PMID:Excluding blood donors at high risk of HIV infection in a west African city. 827 19


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