ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Infection with the human immunodeficiency virus (HIV-1) leads to a wide range of immunological abnormalities. We have shown that native envelope glycoproteins (gpl20) of HIV-1 inhibit antigen-specific and anti-CD3 induced lymphoproliferation of normal lymphocytes. We have demonstrated that gpl20 binds to CD4 positive T lymphocytes and is internalized. These studies suggest that interaction of gpl20 with the CD4 receptor may be sufficient to inhibit antigen-specific T cell responses that are mediated via the CD3-Ti receptor complex. Such an event could represent another mechanism by which the overall immune function of the CD4 positive T lymphocyte is depressed and may be relevant in planning investigations on the ongoing vaccine trial involving envelope glycoproteins.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Transmission of human immunodeficiency virus (HIV) in semen by sexual intercourse is believed to be a major etiological factor in the spread of the disease. In order to explore the role of sperm in this transmission, cell-free HIV-l(IIIB) was coincubated with human sperm for 5 h. After incubation, unattached HIV-1 was extensively washed off the cells and the presence and location of HIV-1 in or on the sperm was determined by electron microscopic (EM) and immunofluorescence methods. Examination of sperm at the EM level showed that HIV-1 attaches to the sperm surface and enters the sperm through the intact cell membrane. Immunofluorescence studies, using polyvalent anti-HIV antibodies, demonstrated the presence of small round fluorescent particles in 5–10% of sperm heads after 5 h of incubation. A search for HIV-1 receptors (CD4 epitopes) revealed the presence of OKT4 epitopes, including OKT4A, B, D, and F on 5–10% of sperm by epifluorescence microscopy and on 10–20% of sperm by flow-cytometric analysis. These in vitro data suggest that human sperm may be the primary cellular element in the transmission of HIV by semen.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Tumor necrosis factor (TNF) and HIV P24 antigen levels were determined in the serum of intravenous drug abusers (IVDAs), homosexuals, and patients with lymphadenopathy or acquired immune deficiency syndrome (AIDS). The mean TNF level in the serum of normal controls was 12 ± 5 compared to 112 ± 25 pg/ml in the serum of HIV-seronegative asymptomatic IVDAs. This increase of TNF may be due to the variety of infections that these people are exposed to persistently. The mean TNF level in the serum of HIV-seropositive asymptomatic IVDAs was 112 ± 79 pg/ml, 31 ± 24 pg/ml in lymphadenopathy, and 55 ± 19 pg/ml in patients with AIDS. The mean P24 level in the serum of patients with AIDS was 50 ± 13 pg/ml compared to 0 pg/ml in HIV-seronegative subjects, while the other HIV-seropositive groups had relatively low levels. The P24 antigen levels may reflect viral load in these patients. SIL-2R and p2-microglobulin levels were also elevated in patients with HIV infection. The TNF may play a role in the antiviral activity against HIV virus and in the development of full-blown disease after HIV infection.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Expression of high levels of the structural proteins of the human immunodeficiency virus type 1 (HIV-1) requires the presence of two regulatory genes, the trans-activator (tat), and the regulator of virion protein expression (rev, previously called art or trs). The experiments described here show that expression of virion proteins is dependent upon a small region located in the envelope gene called the cis-acting antirepression sequence (CAR). The CAR region of the envelope sequence is both necessary and sufficient for rev-dependent capsid protein expression. The experiments also show that a defect in either rev or CAR results in a dramatic decrease in the accumulation of the genomic and envelope mRNAs and an overproduction of more extensively spliced viral mRNA species.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

The new D-mannose-specific lectin fromGerardia savagliais shown to prevent infection of H9 cells with human immunodeficiency virus type 1 (HIV-1; strain HTLV-IIIB). At a concentration of 0.2 μM, complete protection was achieved. Even at a 50-fold higher concentration, this lectin is not toxic for the cells. Moreover, the lectin inhibits syncytium formation in the HTLV-IIIB/H9-Jurkat cell system to 100% at 0.2 μ.M. This effect was abolished by coaddition of D-mannose at a stoichiometric ratio of lectin to sugar of 1:500. The lectin-caused inhibition of syncytia formation was observed also in the HIV-1/human lymphocyte system. Perhaps more importantly, it is shown that the lectin reacts with the oligosaccharide side chains of the HIV-1 gpl20 env molecule, which very likely can be classified to the high-mannose oligosac-charides. These data provide the basis for a rational screening for compounds interfering with gpl20-CD4 interactions.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

The clinical and autopsy findings documented in 216 patients with the acquired immune deficiency syndrome (AIDS) are summarized. The respiratory system was most often involved with opportunistic infections and neoplasms diagnostic of AIDS, accounting for one-fourth of all such occurrences. Respiratory failure was the most frequent terminal event, leading to death in two-thirds of AIDS patients. The most common immediate cause of death wasPneumocystis cariniipneumonia, seen in one-third of cases. Autopsy findings modified the clinical impression of the cause of death in 55% of cases. The most common diagnostic disease entity in all organ sites was cyto-megalovirus. The total clinical course of AIDS from diagnosis to death averaged 7 months, while the mean terminal hospital course was 20 days, and these courses did not vary substantially over the period of the study. Strategies for diagnosis, therapy, and management in patients with AIDS may be aided by these findings.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

We projected the direct medical costs of acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC) for the United States during the period 1987–1991, by applying current epidemiologic projections to state-of-the-art medical decision algorithms for diagnosis and treatment of AIDS-related illnesses. We included the cost of azidothymidine (AZT) therapy, as well as other therapeutic innovations likely to be approved by the FDA, and estimated average ARC patient treatment costs. By combining prospective study data on rates of progression to AIDS with current AIDS incidence data, we arrived at human immunodeficiency virus (HIV) seropreva-lence and AIDS incidence projection that were considerably lower than those of the Public Health Service. We estimated the average total medical costs per patient for AIDS in the 1990s at $27,950-$40,455 and for ARC at $3,621-$4,913 per year (1987 U.S. dollars). We projected the medical costs of AIDS and ARC at $2–4 billion annually by 1991, substantially lower than previous estimates. We projected that Pneumocystis carinii pneumonia and other pulmonary complications would account for the largest share (over 40%) of AIDS medical costs, and that AZT therapy and medication would account for more than 25% of total ARC/AIDS treatment costs by 1991. In our estimates, the total medical costs of treating ARC patients could approach one-half of the costs of treating AIDS patients by 1991, primarily due to costs associated with AZT.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

Deterministic simulation models are used to show that HIV transmission dynamics in homosexual populations can be strongly affected by sexual partner selectiveness. The type of selectiveness or biased mixing examined is where individuals with similar new partnership formation rates are more likely to form a pair than would be expected by chance. The effect of such selectiveness could be strong even when the total number and distribution of new sexual partnerships and sex acts remains constant. This means that in order to predict the future course of HIV transmission and identify the populations at highest risk, we must have information not only on the frequency of new sexual partnerships and types of sex acts, but also on who has sex with whom. Given high sexual partner selectiveness, some groups of homosexuals with low rates of sex and new sex partners would take many decades before a single introduction would generate an epidemic. Epidemics in these groups can be markedly accelerated by only modest contact with higher risk groups. Even in very low activity groups, which if isolated would have no epidemic, an important proportion of their members can be infected when they are not selective. The relative risks of AIDS in groups making high numbers of new sexual partnerships compared to groups making low numbers are markedly affected by sexual partner selectiveness. The models developed were examined using information collected in 1984 from the Coping and Change Study in collaboration with the Chicago Multicenter AIDS Cohort Study. This population was divided into activity groups by the rate at which individuals established new sexual partnerships and then a structure of new sexual partnerships between these activity groups was defined consistent with available data. Even without introducing any behavior change in the models, the proportion of the homosexual population infected was seen to level off temporarily at around 50% after several years as a consequence of saturation in the high risk groups when lower risk groups were not yet being consumed by the epidemic process. Most sex in the study population is casual or anonymous. The sample selection procedures were biased toward individuals who engage in such sex. There is, however, a large group of individuals that avoids the casual and anonymous sex scene. Simulated epidemics indicated that under a variety of conditions, the population that does not engage in casual and anonymous sex could experience an epidemic of HIV infection quite some time after the epidemic in the population that does has waned. If there is practically no mixing between the populations that do and do not engage in casual or anonymous sex, then the epidemic in the latter population could be many decades after the epidemic in the first population. Mixing markedly accelerates this epidemic.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID

摘要:

To examine the relative risk of transmission of the human immunodeficiency virus (HIV) through bites and scratches, we studied 198 health care workers, 30 of whom were traumatized in this fashion while caring for an aggressive AIDS patient. This violent patient frequently bit or scratched others, his mouth had blood and saliva, while his fingernails were at times soiled with semen, feces, and urine. He was HIV antibody and antigen positive. Although HIV was recovered from his peripheral blood lymphocytes, after 2.5 years of serial follow-up, all traumatized personnel were clinically normal, no HIV was cultured from their blood, and all were HIV antibody and P24 antigen negative. We conclude that this viremic AIDS patient, while producing copious amounts of body fluids, failed to infect those caring for him through bites and scratches. The risk of transmission of HIV through this route under similar conditions should be low.

ISSN:0894-9255    

出版商:OVID    

年代:1988

数据来源: OVID