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Biomedical subjects

J Kreiss

Publications and source records attributed to J Kreiss.

35 records · Page 2Linked to original sources
PubMed1994

Human immunodeficiency virus infection in long-distance truck drivers in east Africa.

BACKGROUND: A cross-sectional survey was performed to determine the seroprevalence and correlates of human immunodeficiency virus (HIV) infection among long-distance truck drivers in Kenya. METHODS: Truck drivers along the Mombasa-Nairobi highway were enrolled at a roadside research clinic. A standardized interview and serologic evaluation for HIV and syphilis were conducted. RESULTS: We enrolled 970 truck drivers and their assistants of whom 257 (27%) had HIV antibodies. In univariate analysis, HIV infection was correlated with older age, non-Kenyan nationality, Christian religion, longer duration of truck driving, travel outside of Kenya, less frequent visits to wives, and more frequent visits to prostitutes. Uncircumcised status, history of genital ulcer disease or urethritis during the previous 5 years, and a positive Treponema pallidum hemagglutination assay for syphilis were each associated with positive HIV serostatus. Univariate correlates of uncircumcised status included younger age, non-Kenyan nationality, Christian religion, travel outside of Kenya, and less frequent visits to prostitutes. There was a significant association between uncircumcised status and 5-year history of genital ulcer disease or serologic evidence of syphilis, but not with 5-year history of urethritis. In multivariate analysis, HIV infection was independently associated with uncircumcised status (adjusted odds ratio [OR], 4.9; 95% confidence interval [CI], 2.8 to 8.4), history of genital ulcer disease (adjusted OR, 2.4; 95% CI, 1.5 to 4.1), history of urethritis (adjusted OR, 1.8; 95% CI, 1.1 to 2.9), more frequent sex with prostitutes (more than once per month; adjusted OR, 1.7; 95% CI, 1.1 to 2.8), and positive T pallidum hemagglutination assay (adjusted OR, 1.2; 95% CI, 1.0 to 1.4). The attributable risk percentage for the association between HIV and uncircumcised status was 70%, and the population attributable risk was 25%. CONCLUSIONS: Truck drivers in east Africa are at high risk of HIV infection. The strongest correlates of HIV seropositivity were uncircumcised status and history of both ulcerative and nonulcerative sexually transmitted diseases.

Adolescent↗
PubMed1994

Human T cell lymphotropic virus type I infection among female sex workers in Peru.

Four hundred female sex workers attending a sexually transmitted disease clinic in Lima, Peru, were interviewed for demographic information and medical, contraceptive, and sexual practice histories. Cervical cultures were done for Neisseria gonorrhoeae and Chlamydia trachomatis, and serum was tested for antibodies to human immunodeficiency virus, human T cell lymphotropic virus type I (HTLV-I), Treponema pallidum, C. trachomatis, herpes simplex virus type 2 (HSV-2), and Haemophilus ducreyi. The prevalence of HTLV-I increased with duration of prostitution from 3.6% (< 3 years) to 9.3% (3-6 years) to 15.9% (> 6 years; P < .01). After adjustment for duration of prostitution, reduced risk of HTLV-I was significantly correlated with condom use for more than half of all sexual exposures for > 3 years (odds ratio [OR], 0.34; 95% confidence interval [CI], 0.13-0.89). Further adjusting for condom use, HTLV-I seropositivity was associated with C. trachomatis (OR, 3.7; 95% CI, 1.4-13.2) and with antibody to HSV-2 (OR, 3.7; 95% CI, 0.5-29.6). Thus, duration of prostitution, lack of consistent condom use, and past infection with C. trachomatis were significantly associated with HTLV-I seropositivity.

Adult↗
PubMed1994

Association between cervical inflammation and cervical shedding of human immunodeficiency virus DNA.

A cross-sectional study was conducted among prostitutes in Nairobi, Kenya, to determine the prevalence and correlates of cervical human immunodeficiency virus (HIV) DNA. Ninety-two HIV-seropositive prostitutes were evaluated during 137 clinic visits. Cervical HIV DNA was detected by polymerase chain reaction assay in 36 (39%) women at initial visits and in 40 (44%) women at any visit. There was a significant correlation between cervical HIV and microscopic evidence of cervical inflammation (odds ratio [OR], 7.2; 95% confidence interval [CI], 2.1-24.6). Using multivariate analysis to adjust for possible confounding, the adjusted OR for the association between cervical inflammation and cervical HIV DNA was 8.7 (95% CI, 2.0-37.2). Conditions associated with cervical inflammation are associated with the detection of HIV proviral DNA. Whether such conditions lead to increased infectivity remains to be proven.

Adult↗
PubMed1993

Human immunodeficiency virus infection among high-risk seronegative prostitutes in Nairobi.

To determine the frequency and duration of antibody-negative human immunodeficiency virus (HIV) infection among heterosexually exposed African women, 56 HIV-seronegative female prostitutes in Nairobi were studied. Polymerase chain reaction (PCR) was used to detect HIV DNA in peripheral blood at enrollment, and women were followed prospectively with serologic testing to determine HIV seroincidence. Six women (11%) were infected with HIV by PCR criteria at enrollment. Seroconversion occurred in 5 of these subjects within 1-12 months, while the sixth remained seronegative when last evaluated at 5 months. The cumulative annual seroconversion rate in the entire cohort was 38%. Using maximum likelihood analysis, the mean interval between HIV infection and seroconversion was estimated to be between 3 and 4 months, similar to that described for homosexual men and blood product recipients in the United States. Prolonged HIV infection in the absence of antibodies appears to be uncommon in this setting.

Adult↗
PubMed1992

Role of GDP in formyl-peptide-receptor-induced activation of guanine-nucleotide-binding proteins in membranes of HL 60 cells.

Membranes of myeloid differentiated human leukemia (HL 60) cells contain receptors for the chemotactic peptide, fMet-Leu-Phe (fMet, N-formylmethionine), interacting with pertussis-toxin-sensitive guanine-nucleotide-binding proteins (G proteins). Agonist activation of the receptors increases binding of the GTP analog, guanosine 5'-[gamma-thio]triphosphate (GTP[S]), to membrane G proteins, at 30 degrees C only in the presence of exogenous GDP. In contrast, at 0 degrees C fMet-Leu-Phe stimulated binding of GTP[S] to G proteins maximally without addition of GDP. Under conditions resulting in marked degradation of membrane-bound GDP, control binding of GTP[S] measured at 0 degrees C was significantly increased, whereas the extent of agonist-stimulated binding was reduced. Furthermore, there was a rapid spontaneous release of membrane-bound GDP at 30 degrees C, but not at 0 degrees C. The data suggest that in intact membranes of HL 60 cells G proteins are initially in a GDP-liganded form, which state allows the receptor-induced exchange of bound GDP for GTP[S] at low temperature. In contrast, at or near physiological temperature, bound GDP is rapidly released (and degraded), resulting in unligated G proteins to which GTP[S] will bind independently of agonist-activated receptors.

Alkaline Phosphatase↗
PubMed1991

Long distance truck-drivers: 1. Prevalence of sexually transmitted diseases (STDs).

A cross section study was conducted among long distance truck drivers to determine the prevalence of sexually transmitted diseases (STDs) and antibodies to human immunodeficiency virus (HIV). A total of 8 drivers and their assistants en route from port of Mombasa to countries in East and Central Africa were enrolled into the study. Blood was taken for HIV and syphilis serology. Discharges from urethra and genital ulcer disease (GUD) were cultured. Seroprevalence for HIV was 18% and 4.6% for syphilis. Fifty percent of Neisseria Gonorrhea cultured were penicillinase producers. Most of the men with urethral discharge and all the GUD were culture negative, probably due to prior treatment. Lack of circumcision, past history of GUD and urethritis were significantly associated with HIV seroconversion.

Adolescent↗
PubMed1991

The Nairobi STD program. An international partnership.

Since 1980, Canadian, Belgian, and American scientists have been working together with colleagues in Kenya to understand the epidemiology and biology of sexually transmitted diseases (STDs) in Africa. The rapid spread of human immunodeficiency virus has dramatically increased the importance of this information. Interventions to slow the spread of all STDs and to reduce their consequences are now our major priority. However, this will require continuing research, ongoing training of scientists, epidemiologists, and technologists, and increasing financial support from industrialized societies.

Developing Countries↗
PubMed1990

The increasing frequency of heterosexually acquired AIDS in the United States, 1983-88.

Of 88,510 cases of acquired immunodeficiency syndrome (AIDS) reported in adults in the United States from 1983 through 1988, the percentage attributed to reported heterosexual contact with persons known to be infected or at increased risk of infection with human immunodeficiency virus (HIV) has increased steadily from 0.9 percent in the first quarter of 1983 to 4.0 percent in the fourth quarter of 1988, from 0.1 (in 1983) to 1.4 percent (in 1988) among men, and from 13 (in 1983) to 28 percent (in 1988) among women. Among women, the cumulative incidence of AIDS attributable to heterosexual contact per million population is over 11 times greater for Blacks and Hispanics than for Whites. Among men, this incidence is over 10 times greater for Blacks and four times greater for Hispanics than for Whites. The pattern of distribution of heterosexually acquired AIDS parallels the distribution of other heterosexually transmitted diseases, which are also more frequent in Black and Hispanic inner-city populations. Drug use, exchange of sex for drugs or money, and early onset of sexual activity in adolescents are increasingly associated with heterosexually transmitted infections and are likely to be very important in heterosexual transmission of HIV in inner-city US populations.

Acquired Immunodeficiency Syndrome↗
PubMed1983

Antibodies to human T-cell leukemia virus membrane antigens (HTLV-MA) in hemophiliacs.

Along with homosexual men, Haitians, and intravenous drug abusers, hemophiliacs are at high risk of contracting acquired immunodeficiency syndrome (AIDS). An earlier study revealed that 36 percent of a group of the AIDS patients had antibodies to cell membrane antigens associated with the human T-cell leukemia virus (HTLV-MA), whereas only 1.2 percent of matched asymptomatic homosexual controls had these antibodies. In the present experiments, serum samples from 172 asymptomatic hemophiliacs were examined for the presence of antibodies to HTLV-MA. Such antibodies were detected in 5 to 19 percent of the hemophiliacs examined from four geographical locations, but in only 1 percent or less of laboratory workers, normal blood donors, donors on hemodialysis, or donors with chronic active hepatitis.

Antibodies, Viral↗
PubMedDate not supplied

Beta-2 microglobulin as a marker of HIV disease status in Nairobi, Kenya.

Serum beta-2 microglobulin (beta 2-M) has prognostic value similar to lymphocyte profiles for predicting disease progression in those infected with the human immunodeficiency virus (HIV). However, the relationship between beta 2-M and HIV disease progression among inhabitants of countries with endemic tropical diseases has not been evaluated. To determine the relationship between serum beta 2-M levels and HIV infection and disease status in an African population, serum beta 2-M levels were measured in 369 patients attending a sexually transmitted disease (STD) clinic in Nairobi, Kenya. Mean serum beta 2-M was significantly higher in HIV seropositive than in HIV seronegative individuals. Among HIV infected patients, higher mean beta 2-M levels were observed in those with HIV associated symptoms or laboratory markers of advanced HIV disease. Significant inverse correlations between beta 2-M and the percentage of CD4 lymphocytes or CD4/CD8 ratio were found. These findings suggest that beta 2-M measurements may have prognostic value for HIV infected populations in developing countries.

Biomarkers↗
PubMedDate not supplied

Syphilis and HIV infection among prisoners in Maputo, Mozambique.

A cross-sectional study was carried out among 1284 male and 54 female prisoners to assess the prevalence of and risk factors for sexually transmitted diseases (STD) in 4 correctional institutions of Maputo, Mozambique. Among the men, 32% reported a history of prostitute contact and 41% reported a history of STD. Only 9% reported having ever used condoms. Seventy (5.5%) men reported having had sexual intercourse while in prison, in all but one instance this involved sex with another man. There was no reported intravenous drug use. One hundred and four (7.8%) inmates had positive serological tests for syphilis and 8 (0.6%) had antibodies to HIV. Among men, syphilis was associated with a history of genital ulcer [odds ratio (OR) = 3.1, 95% confidence interval (CI) = 1.4, 6.4] and uncircumcised status (OR = 1.5, 95% CI = 1.0, 2.5). This study demonstrates that syphilis is common among inmates in Maputo and that risk behaviours for STD transmission exist within Maputo prisons. There is a need for STD screening and treatment programmes within prisons in Mozambique and the introduction of educational interventions, including condom promotion.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Efficacy of nonoxynol 9 contraceptive sponge use in preventing heterosexual acquisition of HIV in Nairobi prostitutes.

OBJECTIVE: To determine the efficacy of the nonoxynol 9 contraceptive sponge in preventing sexual acquisition of the human immunodeficiency virus (HIV). DESIGN: Prospective, randomized placebo-controlled trial. SETTING: Research clinic for prostitutes in Nairobi, Kenya. PATIENTS AND INTERVENTIONS: One hundred thirty-eight HIV-seronegative women were enrolled, of whom 74 were assigned to nonoxynol 9 sponge use and 64 to placebo use. These two groups did not significantly differ with respect to demographic characteristics, sexual practices, or prevalence of genital infections at enrollment, except for a lower number of sex partners per week and a higher initial prevalence of genital ulcers among women assigned to nonoxynol 9 sponge use. Among the 116 women who returned for follow-up, the mean durations of follow-up were 14 and 17 months for the two groups, respectively. MAIN OUTCOME MEASURE: HIV seroconversion. RESULTS: Nonoxynol 9 sponge use was associated with an increased frequency of genital ulcers (relative risk [RR], 3.3; P less than .0001) and vulvitis (RR, 3.3; P less than .0001) and a reduced risk of gonococcal cervicitis (RR, 0.4; P less than .0001). Twenty-seven (45%) of 60 women in the nonoxynol 9 sponge group and 20 (36%) of 56 women in the placebo group developed HIV antibodies. The hazard ratio for the association between nonoxynol 9 sponge use and HIV seroconversion was 1.7 (95% confidence interval [CI], 0.9 to 3.0). Using multivariate analysis to control for the presence of genital ulcers at enrollment, the adjusted hazard ratio for the association between nonoxynol 9 sponge use and seroconversion was 1.6 (95% CI, 0.8 to 2.8). CONCLUSIONS: Genital ulcers and vulvitis occurred with increased frequency in nonoxynol 9 sponge users. We were unable to demonstrate that nonoxynol 9 sponge use was effective in reducing the risk of HIV infection among highly exposed women.

Adult↗