ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

We have obtained 15 HIV-2 isolates from the peripheral blood mononuclear cells (PBMCs) of 24 HIV-2-infected west African people. The frequency of virus isolation correlated with the severity of HIV-2 infection; only three isolates were obtained from 11 asymptomatic individuals, whereas virus was isolated from nearly all (12 of 13) individuals with symptoms. The HIV-2 isolates showed distinct replicative and cytopathic characteristics and, similarly to HIV-1 isolates, could be divided into two major groups: rapid/high and slow/low. Rapid/high isolates, i.e. isolates with the ability to replicate in tumour cell lines, were obtained from individuals with symptomatic HIV-2 infection and CD4+ lymphocyte counts < 360/μl blood; these isolates induced syncytia in PBMC cultures. HIV-2 isolates unable to replicate continuously in tumour cell lines (slow/low isolates) induced small syncytia, cell death, or no cytopathic effect at all. All HIV-2 isolates obtained from asymptomatic individuals showed a slow/low replication pattern.

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

Sensitive enzyme-linked immunosorbent assay-based methods are described for monitoring the binding of envelope glycoproteins from HIV-1 and HIV-2 to soluble CD4 (sCD4). Each of the assays has different properties suitable for different applications, but all can be used to characterize recombinant antigens and to screen for inhibitors of the gp120-CD4 interaction. Recombinant mammalian gp120 (Celltech) binds to sCD4 with high affinity (3 nM); this interaction is inhibited by sera from HIV-infected individuals and by specific monoclonal and polyclonal antibodies raised to a component of the CD4 binding site on gp120. The affinity for sCD4 of HIV-2 viral gp120 is shown to be approximately 25-fold lower than that of HIV-1 gp120 (viral or recombinant).

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

We compared four preparations of recombinant HIV-1 envelope glycoprotein: mammalian (Chinese hamster ovary cells) gp120 (Celltech); baculovirus gp120 from American Biotechnologies Inc. (ABT) and from MicroGeneSys (MGS); and baculovirus gp160 (Institute of Virology, Oxford, UK). Each envelope glycoprotein binds to a neutralizing monoclonal antibody (MAb) directed against the V3 loop, confirming the integrity of this type-specific neutralization epitope. MGS gp120 binds abnormally well to a MAb which recognizes an epitope preferentially exposed on denatured gp120. Consistent with this finding, MGS gp120 binds to soluble CD4 (sCD4) with an affinity 50–100-fold lower than that of Celltech gp120. The affinity of Celltech gp120 from sCD4 is 2.3 nM, indistinguishable from that of gp120 extracted from HIV-1 virions. Baculovirus gp120 (ABT) and gp160 also have a high affinity for sCD4. A significant proportion of anti-gp120 antibodies in HIV-positive human sera recognize epitopes that are dependent on the mammalian glycosylation pattern, and a human HIV-positive serum inhibits the binding of mammalian gp120 to sCD4 five- to 10-fold more potently than it inhibits baculovirus gp120 binding to sCD4.

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

We performed a retrospective study on 112 patients with AIDS-related pneumonias who underwent bronchoscopy and in whomPneumocystis cariniipneumonia (PCP) and/or cytomegalovirus (CMV) were identified in bronchoalveolar fluid (BAL). CMV was identified by detection of early antigen fluorescent foci (DEAFF) testing in cell cultures of BAL fluid. The short- and long-term survival of all patients was similar regardless of whether PCP, CMV or both were detected at bronchoscopy. Ten out of 14 patients with CMV alone and 13 out of 26 with both CMV and PCP were treated with anti-CMV therapy, but the short- and long-term mortality was similar to that in patients who had no specific antiviral therapy. Extrapulmonary recurrence of CMV (retinitis or gastrointestinal disease) occurred in 22% of patients with evidence of CMV in BAL compared with 16% of those with PCP alone, but this difference was not statistically significant and this recurrence rate was independent of anti-CMV therapy. Detection of CMV shedding from more than one site (BAL, urine, throat or blood) was associated with a worse prognosis at 3 months than in patients in whom CMV was detected in BAL alone. It does not appear that finding CMV shedding is a guide to the cause of pneumonia or an indication for treatment in AIDS patients.

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

To determine the efficacy of enzyme immunoassays (EIAs) for antibodies against HIV-1 in detecting HIV-2-infected blood, we tested 55 HIV-2-positive sera with seven Food and Drug Administration-licensed EIA kits. The percentage detection of HIV-2 sera giving positive reactions with these kits varied between the various manufacturers from 60 to 91%. Observations based on a small number of sera (n = 13), suggest that HIV-2-positive blood collected from apparently healthy people (blood donors, prenatal clinics) are detected with a greater frequency (&OV0398; = 89%) than blood from AIDS patients or patients (n = 32) hospitalized with other infectious diseases (&OV0398; = 72%). Based on these results and the low incidence of HIV-2 infection observed in the USA, it was concluded that screening with HIV-2-specific tests would not significantly increase the number of HIV-2-positive people detected by current screening programs. However, due to the poor sensitivity of certain HIV-1 assays for HIV-2 antibodies, HIV-2 sera without cross-reacting antibodies will escape detection. Surveillance for HIV-2 might then be improved by the availability of HIV-1 and HIV-2 combination assays.

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

The effect of cigarette smoking on CD4+ T lymphocytes was investigated in the San Francisco Men's Health Study cohort. The cohort was established by probability sampling in 1984 to study infection with HIV. Smoking showed an association with increased CD4+ cell counts in all men but the effect was attenuated in HIV-seropositive men (85 cells/μl difference in median counts, non-smokers compared with smokers) compared with HIV-seronegative men (230 cells/μl difference in median counts). The positive dose response between packs smoked per day and CD4+ counts observed in uninfected men was substantially reduced in infected men (slope 87 versus 27 cells/μl). Analysis of data from HIV seroconverters suggest that smokers' counts fall faster than non-smokers' following infection, and that response to smoking becomes less pronounced soon after infection. This report demonstrates that those who monitor CD4+ cell counts in HIV-infected individuals for clinical and/or research purposes should also consider smoking status.

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

To examine the effect of the revision of the US national AIDS case definition in September 1987, we compared demographic and clinical information for AIDS patients diagnosed and reported to the San Francisco Department of Public Health between 1 September 1987 and 31 October 1989. Of the 3167 patients diagnosed and reported during the study period, 584 (18%) met the revised case definition only, increasing AIDS case reporting in San Francisco by 23%. One hundred and thirty-four of these 584 patients (23%) subsequently developed diagnoses meeting the old definition. After adjusting for this proportion, the revised case definition increased reporting by 17%. The mean time between initial diagnosis with a disease meeting the revised definition and subsequent development of a disease meeting the old definition was 18.5 months. Patients who met the revised case definition only were slightly older and more likely to be Black, female, and intravenous drug users (IVDUs) than those meeting the old case definition. The majority of patients who met the revised case definition only had initial diagnoses of HIV wasting syndrome (26%), HIV encephalopathy (21%), and presumptivePneumocystis cariniipneumonia (19%). The revised AIDS case definition has significantly increased the reporting of severe morbidity associated with HIV infection, particularly among IVDUs.

ISSN:0269-9370    

出版商:OVID    

年代:1990

数据来源: OVID