Barriers to human immunodeficiency virus related risk reduction among male street prostitutes.

Two hundred eleven male street prostitutes between the ages of 18 and 51 years were interviewed and tested for antibodies to the human immunodeficiency virus (HIV). Economic, social, and emotional barriers to the reduction of HIV-related risk behavior were examined within the context of several concepts present in the Health Belief Model (HBM). Three lifestyle factors were found to function as barriers to engaging in risk reduction behavior. Subjects who were more economically dependent on prostitution, perceived less control over the hustling encounter, and reported increased pleasure from sexual activity with their customers were more likely to engage in risk-taking behavior. Prostitutes' perception of the severity of HIV infection was not significantly associated with their risk behavior. Unexpected findings indicated that increases in perceived susceptibility to HIV and perceived benefit of condom use for HIV prevention were significantly related to increased risk-taking behavior. Practical applications of findings in the design and implementation of future HIV-related preventive health education programs are discussed.

PIP: A survey of male street prostitutes in New Orleans, Louisiana, on the social, economic, and psychological barriers to human immunodeficiency virus (HIV)-related risk reduction behaviors has significant implications for the design of health education programs. The 211 subjects, ages 18-51 years, were tested for HIV antibodies and interviewed through use of a semi-structured schedule aimed at eliciting data on life-style and based on the Health Belief Model. 37 (17.5%) of study subjects were HIV-positive. HIV risk behavior was measured on the basis of participation in anal-genital and oral-genital sex, sexual orientation, and syphilis serostatus. High-risk behavior was found to be significantly positively associated with economic dependence on hustling, enjoyment of sex with tricks, and perceived control over hustling, negatively with frequency and quantity of substance abuse. These variables accounted for 6%, 3%, 4% and 4%, respectively, of the total variance in risk behavior. 96% of male prostitutes identified HIV as a serious condition; however, risk-taking behavior was found to increase with increased levels of perceived susceptibility to HIV infection. Finally, risk-taking behaviors increased along with increased in perceptions of the availability and efficacy of condoms. These findings suggest that health education efforts based on promoting HIV infection as a serious condition or emphasizing the effectiveness of condom use will be ineffective without attention to the social context of population groups at greatest risk of HIV infection. Measures most likely to reduce HIV-taking behaviors among male prostitutes are, according to these findings, elimination of the economic incentive for engaging in unsafe sex through the provision of alternative income sources, empowering male prostitutes to exert control over the hustling situation, and promotion of achievement of sexual pleasure through safe sex.

Psychological characteristics of a sample of male street prostitutes.

Two hundred and eleven male street prostitutes were interviewed and administered the SCL 90-R psychological symptom checklist. When compared to nonpatient normals, male prostitutes exhibited significantly higher levels of psychopathology. However, when compared to adult psychiatric outpatients, male prostitutes exhibited significantly less psychopathology on all symptom dimensions of the SCL 90-R except paranoid ideation. The male prostitutes' elevated scores on the psychological symptom checklist may reflect their response to an often dangerous and chaotic environment. However, it is as likely that their psychological functioning leads them to this particular milieu.

The male street prostitute: a vector for transmission of HIV infection into the heterosexual world.

Two hundred and eleven New Orleans male street prostitutes were interviewed and tested for antibodies to the human immunodeficiency virus (HIV). The subjects' lifestyle characteristics and their sex and drug use practices were evaluated to determine the prostitutes' potential to function as a vector for transmission of HIV into populations with currently low infection rates. Information about the customers of the male prostitutes was also obtained from the sample. The period prevalence of HIV in the sample was 175/1000. Many of the male prostitutes reported having wives or girlfriends, some of whom were prostitutes themselves. The prostitutes perceived a majority of their male customers to be heterosexual or bisexual (indicating sexual contact with women as well as men), many (39%) were thought to be married. Results from the study support the argument that male prostitutes serve as a bridge of HIV infection into populations with currently low infection rates through contact with both non-customer sexual partners and customers and thus indirectly to spouses and sexual partners of these individuals.

A murine model of asbestosis.

Balb/c mice were exposed to aerosolized chrysotile fibers and evaluated as a host for the study of asbestos-induced pulmonary disease. Histologically, an initial macrophage reaction was found to progress to "asbestos body" formation and diffuse focal interstitial fibrosis within 1 year of a chronic exposure period. This reaction was most intense in areas adjacent to respiratory bronchioles and alveolar ducts. Two morphologically distinct tumors at the pulmonary visceral surface were also discovered among a high percentage of asbestos-exposed mice. Bronchoalveolar lavage demonstrated an eventual alteration of the retrievable cell populations among the dusted animals. Evaluation of systemic B-lymphocyte activity suggested a stimulation of this cell subset following chrysotile inhalation. These results demonstrate that subsequent to chronic asbestos exposure, the mouse develops pulmonary and immunologic changes very similar to those noted in human asbestosis.

Asbestos-induced alterations of human lymphoid cell mitogenic responses.

Using mitogenic assays, we have investigated the short term effects of two asbestos (amosite and chrysotile) fibers on lymphocyte functions in vitro. These oppositely charged fibers produced different alterations in mitogenesis. The blastogenic responses of concanavalin-A (Con-A) and pokeweed mitogen stimulated human peripheral blood mononuclear cells (PBMN) were significantly increased by the inclusion of 6 micrograms of chrysotile to the culture media. Amosite fibers proved to be inhibitory in all tests. When PBMN were depleted of monocytes, asbestos-related alterations of Con-A responsiveness were unchanged among the remaining cells. However, the addition of chrysotile to phytohemagglutinin (PHA) cultures resulted in a significant increase of the mitogenic response. When PBMN were enriched for T lymphocytes, and again cultured with the mitogens and fibers, the Con-A response still displayed impressive enhancement with chrysotile. In contrast to an intact PBMN population, PHA-induced blastogenesis among these T-enriched lymphocytes was significantly elevated. These experiments demonstrate that asbestos can induce significant changes in the functional integrity of PBMN following a relatively short exposure time in culture.

Diminished suppressor cell function in patients with asbestosis.

Epidemiological and immunological studies of asbestos workers documented abnormalities in humoral and cell-mediated immunity which could result from defective immunoregulation. This study tests this hypothesis with comparison of lymphocyte function in age-, sex- and smoking-matched subjects with asbestosis. In vivo measure of delayed hypersensitivity (i.e. skin test response) was significantly depressed to two recall antigens, SKSD and Candida, in asbestosis patients. Skin reaction to dinitrochlorobenzene (DNCB) was not depressed, although lymphocytes of patients giving positive skin test reactions demonstrated a significantly lower (P less than 0.001) proliferative response to dinitrobenzene sulphonic acid (DNBSO3) in vitro. T cell counts (E-rosettes) were normal in patients with asbestosis, although a subset of T cells, those forming sheep erythrocyte rosettes after prolonged incubation (Elate), were significantly depressed (P less than 0.003). This population has been equated with 'suppressor' cells (Grossi et al., 1978). Numbers of B cells were increased nearly two-fold over controls. Mitogen response of lymphocytes was normal except at suboptimal doses of mitogens where the response is known to be influenced by suppressor cell activity, which was significantly elevated. Suppressor cell function, as determined by stimulation of peripheral blood lymphocytes preincubated with concanavalin A, was also significantly decreased in asbestosis patients (P less than 0.01).

A comparison of cell-mediated immunity and suppressor T-cell function in asthmatic and normal children.

The role of general and suppressor T-cell function was investigated in a group of twelve children with atopic asthma and ten non-atopic control children. Studies of active E rosettes, lymphocyte stimulation, and delayed type skin responsiveness revealed no statistically significant group differences. Data obtained employing a concanavalin A-induced, suppressor T-cell assay revealed that the asthmatics generated significantly less suppressor cell activity than did the normal control group. There was no correlation between lack of suppressor cell function and serum IgE levels. The results of this study support the concept of suppressor T-cell dysfunction in atopic disease.

Aberrant blastogenic response to LPS in experimental gingivitis of elderly subjects.

The blastogenic response of peripheral blood leukocytes to lipopolysaccharide (LPS), phytohemagglutinin (PHA) and LPS/PHA mixtures was followed over a short course of experimental gingivitis in elderly subjects (65-81 years) who strictly avoided oral hygiene procedures for periods up to 9 d. The leukocytes responded poorly to LPS, PHA and to LPS/PHA combinations. The concomitant heightened sensitivity of the gingiva to dental plaque among the elderly subjects may relate to the altered leukocyte response in this age group.

Indirect blastogenesis of peripheral blood leukocytes in experimental gingivitis.

The blastogenic response of peripheral blood leukocytes to lipopolysaccharide (LPS) was followed over a short course of experimental gingivitis, developed in human volunteers who strictly avoided oral hygeine procedures for periods up to 9 days. Eleven young males initially received thorough dental prophylaxes and supervised oral hygeine until they acquired optimal gingival health. At this point, leukocytes (5 X 10(5)) incubated with 1.5 to 25 mug of LPS in serum-free media showed no response as measured by tritiated thymidine uptake. Coincubation of cells with LPS and phytohemagglutinin (PHA), however, caused synergistic enhancement of blastogenesis in every LPS-PHA dose combination tried. With progressive accumulation of dental plaque and the concomitant development of gingival inflammation, this synergistic response was lost and replaced, proportionately, by a direct response to LPS. The leukocyte response to PHA was marginally enhanced with gingivitis.

Elevation of a serum component in periodontal disease capable of modulating chemotactic infiltration.

Serum from dental patients was examined for its capacity to affect migration of polymorphonuclear leukocytes toward a complement-independent chemotactic factor, bacterial filtrate of Escherichia coli, (BF). Seven subjects with advanced periodontitis, documented with clinical measurements of pocket depth, loss of attachment, indices for gingival inflammation and oral hygiene, were paired with normal subjects of similar age and sex. This study shows that patients whose only apparent clinical symptom was severe periodontal inflammation harbor a heat-stable, serum component which neutralizes factors chemotactic for polymorphonuclear leukocytes. A role for this component in modulation of inflammatory infiltration is discussed.