Gender ideology, same-sex peer group affiliation and the relationship between testosterone and dominance in adolescent boys and girls.

Although the role of testosterone in the aetiology of social dominance is often suggested, surprisingly few studies have addressed the relationship between sex steroid hormones and dominance as a personality trait. In this paper, the relationship between testosterone and dominance is studied in a sample of adolescent boys and girls, taking into account the moderating role of gender ideology and same-sex peer group orientation. A direct association between free testosterone (FT) and dominance was found in girls but not in boys. In boys, masculine ideology moderated the relationship between FT and dominance, while in girls the relationship between FT and dominance was moderated by same-sex peer group affiliation.

2d:4d, sex steroid hormones and human psychological sex differences.

Studies on 2d:4d, the ratio between the second and the fourth digit, as a possible indicator of prenatal androgen exposure, have failed to produce consistent results. This paper analyzes the relation between 2d:4d, sex steroids and well-documented sex differences in characteristics such as depression, dominance, and aggressive (ART) and non-aggressive adolescent risk-taking (NART) in a comparatively large sample of adolescent boys (N=301, mean age: 14.4 years) and girls (N=298, mean age: 14.3 years). Boys had on average a lower 2d:4d than girls (F=42.15; p<0.001). With respect to boys, controlling for age and pubertal development (PD), a small but marginally significant positive association was found between 2d:4d and total testosterone (TT) (r=0.11; p<0.05). In girls a significant association was found between 2d:4d and SHBG (r=0.18; p<0.01). However, relationships between 2d:4d and hormones depended on the phase of the menstrual cycle, with 2d:4d being negatively associated with FT (B=-0.013; p<0.05) once a positive association between 2d:4d and FT for girls in the mid-cycle group (B=0.019; p<0.01) is taken into account. With respect to sex differences in characteristics, we found evidence of a relationship between 2d:4d and depression in boys (r=-0.14; p<0.05) but not between 2d:4d and dominance, ART or NART. No relationships were found between 2d:4d and any of these variables in girls.

The cognitive structure of the domain of safe and unsafe gay sexual behaviour in Belgium.

This study compares the cognitive structure of sexual techniques of safe versus unsafe gay men older than 30 years. Subjects rated 25 sexual techniques by six bipolar adjective scales making up a short version of the semantic differential. Scales measured subjects' perception of the safety and gratification potential of the sexual techniques. We used cluster analysis, multidimensional scaling and factor analysis. Subjects reporting no unprotected anal sex with non-steady partners (N = 312) differ from men reporting unsafe behaviour (N = 19). Safe and unsafe men used different main categories to structure the domain of sexual behaviour. Within the group of safe men, the domain of sexual behaviour structured by perceptions of gratification and safety seem to mirror the epidemiological structuring of sexual techniques using the non-penetration versus penetration, and transmission of body fluids versus no transmission of fluids dimension. Among risky men, this structuring is not that clearly present. We found different estimations of the level of risk associated with unprotected insertive versus receptive anal sex in combination with a higher perception of the gratification potential of the former. Unsafe men seem to make a noticeable difference between their own and their partner's risk and gratification.

Suicidal acts and ideation in homosexual and bisexual young people: a study of prevalence and risk factors.

BACKGROUND: Suicide attempts are the most robust clinical predictor of suicide, which is now the second cause of death among young people in many countries. Previous research has shown an increased risk of attempted suicide associated with a homosexual orientation. However, the mechanisms underlying this increased risk are not yet clear. This study therefore aimed to determine the risk of attempted suicide and the effect of potential risk factors on the occurrence of suicidal ideation and behaviour among homosexual youngsters. METHODS: The association between suicidal ideation and behaviour and potential risk factors was assessed by means of a questionnaire in a general population sample of homosexual or bisexual young people and a control sample consisting of school pupils. RESULTS: A twofold increased risk of suicidal ideation was found associated with a homosexual or bisexual orientation. A significantly increased risk of attempted suicide associated with homosexuality or bisexuality was found in females. Independent of sexual orientation, depression was identified as a significant risk factor for suicidal ideation, while suicidal behaviour was associated with low self-esteem, higher levels of hopelessness and suicidal behaviour in someone close. Among homosexual or bisexual young people, less satisfying homosexual friendships were an additional risk factor for suicidal behaviour. CONCLUSIONS: The identified increased risk of suicidal ideation among homosexual or bisexual young people is associated with depression and may lead to suicidal behaviour, independent of sexual orientation, especially in the presence of a role model of suicidal behaviour, and among those with unsatisfying friendships.

Younger versus older gay men: risks, pleasures and dangers of anal sex.

This study reports on the practice and the pleasure and danger perceptions of protected and unprotected anal sex of young adult gay men (< or = 30) and older gay men (30+). It is assumed that, if prevention efforts were successful, younger gay men-sexually socialized during the AIDS era-should have more favourable perceptions of anal sex with a condom. Data from a cohort of gay men in Flanders, Belgium (1993, n = 553) are used in this analysis. The results indicate that younger gay men do not differ from older gay men in the riskiness/safety of their actual sexual behaviour. However, younger men hold different valuations regarding anal sex. They report a higher appraisal for both insertive and receptive anal sex with a condom. The perceived safety of protected anal sex is also higher among the younger men. We also found that younger men with a steady partner report more gratification from insertive anal sex with a condom than do older partnered men. We interpret these findings as evidence of the effectiveness of HIV prevention efforts.

The social support of Flemish gay men: an exploratory study.

This study describes the sources and level of social support of Flemish gay men using data from surveys conducted in 1989 (n = 379) and 1993 (n = 553). Five indicators of social support were used: positive appraisal, perceived isolation, enacted social support, perceived material support, and perceived emotional support. The main results, which are cross validated across the two samples, are as follows. Most men score high on all five indicators of social support. Social relationship conflicts are either nonspecific or related to the steady partner. Isolation and lack of positive appraisal are also nonspecific or related to gay friends. Parents still function as important sources of material support. Men without a steady partner and men with low socioeconomic status experience more isolation. Single men also report less positive appraisal, while older men have less material support.

Rapid identification of Mycobacterium xenopi from bacterial colonies or "Bactec" culture by the polymerase chain reaction and a luminescent sandwich hybridization assay.

Oligonucleotide primers were used in the polymerase chain reaction (PCR) to amplify a specific 584-bp DNA fragment, located in the 16S RNA gene of Mycobacterium xenopi. This set of primers, X222 and X224, was able to discriminate between the pathogen and other mycobacterial species as well as non-mycobacterial strains; it detected down to 3 fg of M. xenopi DNA, i.e. about one genome equivalent. These oligonucleotide primers proved suitable for the routine identification of M. xenopi cultures, starting from one single colony on solid medium or from a liquid culture in Middelbrook 12B "Bactec" medium. In addition, a luminescent hybridization assay was designed for use on PCR-amplified DNA. This system, which, for capture, relied on a matrix-bound oligonucleotide (M30) specific for the genus Mycobacterium and, for detection, on a biotinylated xenopi-specific X221 probe, proved fully specific, highly sensitive and rapid for the evaluation of M. xenopi Bactec cultures at low growth index.

Coming out and AIDS-related high-risk sexual behavior.

How the withdrawal of social support associated with the coming out of gay men influences AIDS-related sexual risk-taking among Flemish (Belgian) gay men is analyzed. Recruited via key persons, the 379 gay men in this nonclinical cohort completed a lengthy, computerized questionnaire dealing with diverse aspects of gay life and culture. Independent variables include demographic characteristics, AIDS knowledge, coming-out histories, six social support dimensions, and personal resources. The dependent variables were insertive and receptive anal intercourse with and without a condom. Stepwise regression explained, respectively, 41.2, 38.4, 18.4, and 14.2% of the variance. Absence of appraisal (the view that others approve of the way one does things or feels about things) led to higher frequencies of insertive anal sex (both with and without a condom). The experience of emotional conflict lowered the use of condoms by the insertive partner in anal intercourse. Disapproval by significant others of being gay also led to higher levels of receptive anal intercourse without a condom. Subjects with a high belief in mastery had higher frequencies of risk-taking, suggesting that the combination of the experience of negative reactions and high mastery lead to greater involvement in risky sexual behavior. Findings are interpreted within the theoretical framework of the coming-out process and gay identity formation.

PIP: Individuals who recognize and freely admit that they are either homosexual or bisexual may be rejected by their peers, families, and others. Adequate social support, however, has been shown to lead to a heightened sense of well-being and health. It has also been shown to encourage individuals to adopt and maintain healthier lifestyles. There are important correlations between social support and self-esteem, control/mastery, and stress management. The withdrawal of social support following the coming out of gay people can have serious detrimental effects on their social and emotional well-being. 379 gay and bisexual men completed a questionnaire in 1989 about various aspects of gay life and culture in the course of a study about how life stress, associated with the disapproval of being gay and the absence or withdrawal of social support, influences the level of sexual risk-taking. The men were aged 17-78 years, with 81.9% aged 21-40. Teens and men over age 50 are underrepresented in the cohort. As in most research on gay men, this cohort is more highly educated than the general population, with more than 50% having some education beyond secondary school. Men who felt that others approve of their life choices and lifestyle had higher frequencies of insertive anal sex both with and without a condom. Emotional conflict, however, lowered the use of condoms by the insertive partner in anal intercourse. Disapproval by significant others of being gay also led to higher levels of receptive anal intercourse without a condom. Respondents with a high belief in mastery took risks more often. It therefore may be assumed that combining the experience of negative reactions with high mastery leads to greater involvement in risky sex behavior.

Plasma lipoprotein(a) values and severity of coronary artery disease in a large population of patients undergoing coronary angiography.

To determine possible associations between lipoprotein(a) [Lp(a)] and the severity of coronary artery lesions, we measured lipid, apolipoprotein, and Lp(a) in a large population of Belgian patients (n = 1054) undergoing coronary angiography. In both women and men, univariate analysis demonstrated significant differences in the Lp(a) concentrations according to the severity of the coronary stenosis. However, after adjustment for possible confounding factors, many of these differences were attenuated, indicating that other variables that differentiate patients from control subjects also influence Lp(a) distribution. Differences in lipid, apolipoprotein, and Lp(a) concentrations between male and female patients are discussed.

Rapid detection of tuberculous and non-tuberculous mycobacteria by polymerase chain reaction amplification of a 162 bp DNA fragment from antigen 85.

A polymerase chain reaction (PCR) assay was developed for detection of mycobacteria using amplification of a 162 bp region of the genes coding for the mycobacterial antigen 85 complex. Strains belonging to the Mycobacterium tuberculosis complex were further differentiated from non-tuberculous mycobacteria by hybridization of the PCR derived Southern blot with an internal oligonucleotide probe and washing under stringent conditions. The method allowed rapid and sensitive detection of mycobacterial DNA in uncultured clinical samples. PCR results obtained for Mycobacterium tuberculosis in 206 specimens from 180 untreated patients gave a sensitivity of 93.9% and a specificity of 94.3% compared with the culture. PCR detected DNA from Mycobacterium tuberculosis in seven samples from patients with clinically evident tuberculosis in whom culture was negative. The results suggest that this PCR assay could be used for early and specific diagnosis of tuberculosis.

Alcohol and risky sex: in search of an elusive connection.

Since the publication of the 1986 article by Stall, McKusick, Wiley, Coates and Ostrow, the conclusion that drinking alcohol prior to or during erotic encounters increases the probability of engaging in high-risk sexual behavior has been widely accepted, despite some contradictory findings from research on this hypothesis. This paper presents the results of tests of the alcohol/risky-sex hypothesis in a cohort of gay men in Flanders, Belgium. Failing to find evidence to support the hypothesis of a general effect of alcohol on sexual risk taking, we argue that previous conclusions on this matter must be viewed with extreme caution, especially in light of the implications that this failure to replicate has for AIDS prevention programs. Cultural, social, and methodological factors that could account for this failure to replicate are discussed in the context of a review of the literature on this hypothesis.

Hepatitis C among risk groups for HIV and hepatitis B.

In order to obtain more information on sexual transmission of hepatitis C (HCV) we compared different high-risk groups for HIV and hepatitis B to see if they were seropositive for HCV. A high seroprevalence (38/81) of hepatitis C (HCV) was found among intravenous drug users. Nursing staff (n = 35) and patients of a dialysis unit (n = 57) had a low prevalence of anti-HCV antibodies (0% and 5%, respectively). Serology laboratory technicians also had a very low prevalence (0% out of 29). Among prostitutes (n = 114), healthy homosexual men (n = 132) and HIV-infected homosexual men (n = 31), we found a remarkably low seroprevalence of HCV (3.5%, 0.8% and 0.0% respectively). These data support the view that parenteral exposure to the virus is the most important way of acquiring the infection and that neither heterosexual nor homosexual promiscuity are associated with a high risk of transmission of hepatitis C.

Effect of aspirin on renal function and the prostaglandin-kallikrein systems early after myocardial infarction.

Using a double-blind procedure, 29 patients with a recent myocardial infarction were randomly allocated to a placebo group (n = 14) and to a group receiving aspirin, 300 mg three times a day (n = 15) over 7 days. No change in renal function was observed in either treatment group. Compared with the placebo group, the 24-h urinary excretion of prostaglandin E2 (PGE2) was significantly suppressed in the aspirin group, but the urinary kallikrein activity was unchanged. These results contrast with our previous study of similar patients, in which sulfinpyrazone decreased renal function, as well as the urinary PGE2 and kallikrein excretions. These divergent effects of aspirin and sulfinpyrazone on urinary kallikrein activity could explain the different trends in renal function observed early after myocardial infarction.

Decrease in renal function due to sulphinpyrazone treatment early after myocardial infarction.

Twenty-nine patients with recent myocardial infarction were randomly allocated to a placebo group (n = 14) and to a group (n = 15) who received sulphinpyrazone, 4 x 200 mg daily for 7 days. Renal function significantly and transiently deteriorated in the sulphinpyrazone group compared to the placebo group. In the sulphinpyrazone group the 24 hour-urinary prostaglandin E2 and kallikrein excretion were suppressed. These data suggest that the decrease in renal function caused by sulphinpyrazone early after myocardial infarction could be mediated by an inhibition of renal prostaglandin and/or kallikrein-kinin synthesis.

Double-blind comparison of Diltiazem and placebo in the treatment of exercise-inducible chronic stable angina pectoris.

The effect of Diltiazem, a calcium antagonist drug, were compared with those of placebo on exercise performance. Twenty four patients with exercise-inducible chronic stable angina pectoris were studied over a double-blind period of 8 weeks. The active product was generally well tolerated. Diltiazem was effective in increasing the anginal threshold, in decreasing the ST-segment depression at an identical submaximal workload and in increasing the time to termination of exercise. These results are in accordance with those of others but the mechanisms whereby these effects occur are unclear; the observed results suggest that peripheral effects are not primarily responsible for the drugs' efficacy.