Human immunodeficiency viruses in patients attending a sexually transmitted disease clinic in London, 1982-7.

OBJECTIVE--To determine the prevalence of infection with the human immunodeficiency virus (HIV) in all patients attending a London sexually transmitted disease clinic over four weeks at the end of 1987 and to see how it varied from that in similar samples studied between 1982 and 1986. DESIGN--Anonymous testing of serum samples from consecutive heterosexual and homosexual patients having routine serological investigations for syphilis. Testing was for anti-HIV-I, anti-HIV-II, and hepatitis B core antibody (anti-HBc) and P24 antigen. Age, nationality, sexual orientation, and past sexually transmitted diseases were recorded for each patient. Gonorrhoea rates by quarters were analysed among homosexual and bisexual men and heterosexual men and women from 1981 to 1987. SETTING--Outpatient department of genitourinary medicine. PATIENTS--A total of 1074 patients attending consecutively for syphilis serology. Thirty five homosexual and bisexual men were excluded (these were regular attenders as part of a prospective study of the natural course of HIV infection). MEASUREMENTS AND MAIN RESULTS--The prevalence of anti-HIV-I in homosexual and bisexual men in 1987 was 25.6% (64/250). Results in the same clinic population between 1982 and 1984 had shown a rise in prevalence, which flattened out in 1985-6 and continued at that level. Among heterosexual attenders in 1987 the prevalence of anti-HIV-I was 1% (women 4/412; men 4/377), which contrasted with a prevalence of 0.5% (women 2/395; men 3/757) in January 1986. One homosexual man was seropositive for anti-HIV-II and seronegative for anti-HIV-I. Among homosexual and bisexual men the rate of gonorrhoea had declined by an average of 2.7% a year since 1981, such that by 1987--and for the first time in the clinic--there was no significant difference in the rates between these men and heterosexual men and women. CONCLUSIONS--The appearance of HIV-I infection among heterosexuals indicates a need for more aggressive education programmes and intervention strategies along the lines adopted for homosexual men. Surveillance for HIV-II infection is needed to provide information for future policy in national screening programmes.     

HIV infection in patients attending clinics for sexually transmitted diseases in England and Wales. Collaborative Study by Consultants in Genitourinary Medicine and the Public Health Laboratory Service.

A national study of the prevalence of HIV antibody designed to monitor sexual spread of HIV infection in England and Wales was made of homosexual and heterosexual patients attending sexually transmitted disease clinics in four districts in 1985, seven in 1986, and 14 in 1987. Patients were invited to participate and were counselled. Among homosexual men in two clinics in south east England, HIV antibody was found in 92 (12.9%) of 711 in 1985, 65 (15.2%) of 428 in 1986, and 81 (14.6%) of 556 in 1987: corresponding findings in the other regions were 16 (5.0%) of 321, 41 (6.3%) of 654, and 21 (3.1%) of 678. The prevalence of HIV antibody was higher in homosexual than bisexual men, in patients aged 25 years or more, or with one or more specified minor complaints. Among heterosexual patients in the south east in 1986, HIV antibody was found in seven (3.0%) of 230 men and three (1.3%) of 233 women and in 1987 in 10 (1.0%) of 962 men and seven (0.7%) of 949 women. In other areas corresponding findings in 1986 were two (0.2%) of 950 men and three (0.4%) of 752 women and in 1987 were three (0.06%) of 5312 men and one (0.02%) of 4778 women. All but one of the heterosexual patients with the antibody were intravenous drug abusers or had had sexual contacts in or were from an area abroad with a high prevalence of AIDS. Failure to identify a heterosexual patient with HIV antibody not in a risk group (other than that of being an attender at the clinic) or who did not have a sexual partner in a risk group suggests that their prevalence in the patient population of the clinics in the south east is less than one in 700 and in the other regions less than one in 3000. Refusals to participate increased during the study but comparisons of patients who agreed and refused in terms of age, the presence of symptoms suggesting AIDS, travel abroad, and number of sexual partners a month showed little evidence of selective bias.     

Homosexual women have less grey matter in perirhinal cortex than heterosexual women

Is sexual orientation associated with structural differences in the brain? To address this question, 80 homosexual and heterosexual men and women (16 homosexual men and 15 homosexual women) underwent structural MRI. We used voxel-based morphometry to test for differences in grey matter concentration associated with gender and sexual orientation. Compared with heterosexual women, homosexual women displayed less grey matter bilaterally in the temporo-basal cortex, ventral cerebellum, and left ventral premotor cortex. The relative decrease in grey matter was most prominent in the left perirhinal cortex. The left perirhinal area also showed less grey matter in heterosexual men than in heterosexual women. Thus, in homosexual women, the perirhinal cortex grey matter displayed a more male-like structural pattern. This is in accordance with previous research that revealed signs of sex-atypical prenatal androgenization in homosexual women, but not in homosexual men. The relevance of the perirhinal area for high order multimodal (olfactory and visual) object, social, and sexual processing is discussed.     

Seminal fluid excretion of cytomegalovirus related to immunosuppression in homosexual men.

Seminal fluid samples from 84 Danish homosexual men were successfully cultured to determine the prevalence of cytomegalovirus excretion. Ten (15%) out of 66 men positive for the antibody were found to be excreting the virus. Although the proportion excreting was inversely related to age (p less than 0.01), three men aged over 30 and with many years of homosexual experience excreted the virus. In addition, a 50 year old man with Kaposi''s sarcoma excreted the virus. A further study of the ratio of T cell helpers to suppressors in the men aged over 30 and a series of age matched non-excreting homosexual control or heterosexual men showed that those excreting cytomegalovirus in their seminal fluid had statistically lower ratios (all less than 0.77) than the controls (p less than 0.05). Excretion of cytomegalovirus may be related to re-emergence of latent infection in immunosuppressed homosexual men.     

Neural correlates of sexual arousal in heterosexual and homosexual women and men

Most men have a category-specific pattern of genital and subjective sexual arousal, responding much more strongly to erotic stimuli depicting their preferred sex than to erotic stimuli depicting their nonpreferred sex. In contrast, women tend to have a less specific arousal pattern. To better understand this sex difference, we used neuroimaging to explore its neural correlates. Heterosexual and homosexual women viewed erotic photographs of either men or women. Evoked neural activity was monitored via fMRI and compared with responses to the same stimuli in heterosexual and homosexual men. Overall, a network of limbic (as well as the anterior cingulate) and visual processing regions showed significantly less category-specific activity in women than men. This was primarily driven by weaker overall activations to preferred-sex stimuli in women, though there was also some evidence of stronger limbic activations to nonpreferred-sex stimuli in women. Primary results were similar for heterosexual and homosexual participants. Women did show some evidence of category-specific responses in the visual processing regions, although even in these regions they exhibited less differential activity than men. In the anterior cingulate, a region with high concentrations of sex-hormone receptors, subjective and neural category specificity measures correlated positively for women but negatively for men, suggesting a possible sex difference in the role of the anterior cingulate. Overall, results suggest that men tend to show more differentiated neural responses than do women to erotic photographs of one sex compared to the other sex, though women may not be entirely indifferent to which sex is depicted.     

Is male homosexuality maintained via kin selection?

We tested the kin selection hypothesis of male homosexuality using questionnaire data in a community sample of homosexual and heterosexual men. Homosexual men were no more likely than heterosexual men to channel resources toward family members. Indeed, heterosexual men tended to give more financial resources to siblings than homosexual men. Furthermore, homosexual men were somewhat more estranged from family members, especially from fathers and oldest siblings.     

Evidence against a relationship between dermatoglyphic asymmetry and male sexual orientation

Hall and Kimura (1994) studied the relation between dermatoglyphic asymmetry and male sexual orientation in a sample of 66 homosexual and 182 heterosexual men. They found that more homosexual men possessed a leftward dermatoglyphic asymmetry than did heterosexual men. In this paper, we report a comparative study about the relationship between sexual orientation and dermatoglyphic characteristics, including 60 homosexual men, 76 heterosexual men, and 60 heterosexual women, recruited from the general population, and also from a gay-rights nongovernmental organization, in Salvador, Brazil. Ulnar loops were the most frequent dermatoglyphic pattern in all groups, followed by whorls, arches, and radial loops. A chi-square analysis comparing the frequencies of the patterns in the three groups only showed an excess of ulnar loops in women (p < 0.05) and arches in men (p < 0.01), but did not reveal significant differences between homosexuals and the other groups studied. There was no significant difference between gay and straight men on total ridge count. We found a preponderance of rightward asymmetry in homosexual and heterosexual men, as well as in heterosexual women. Our results do not agree with Hall and Kimura's data indicating that more gay men possessed the minority leftward asymmetry than did straight men. There was no significant difference in leftward asymmetry in the sample studied. The results reported in this paper do not support any relation between dermatoglyphic asymmetry and male sexual orientation, and, thus, any hypothesis concerning a biological intrauterine contribution to adult sexual orientation somehow associated with dermatoglyphic development.     

The interstitial nuclei of the human anterior hypothalamus: an investigation of variation with sex, sexual orientation, and HIV status

The interstitial nuclei of the human anterior hypothalamus (INAH1-4) have been considered candidates for homology with the sexually dimorphic nucleus of the preoptic area of the rat. Volumetric sexual dimorphism has been described for three of these nuclei (INAH1-3), and INAH3 has been reported to be smaller in homosexual than heterosexual men. The current study measured the INAH in Nissl-stained coronal sections in autopsy material from 34 presumed heterosexual men (24 HIV- and 10 HIV+), 34 presumed heterosexual women (25 HIV- and 9 HIV+), and 14 HIV+ homosexual men. HIV status significantly influenced the volume of INAH1 (8% larger in HIV+ heterosexual men and women relative to HIV- individuals), but no other INAH. INAH3 contained significantly more neurons and occupied a greater volume in presumed heterosexual males than females. No sex difference in volume was detected for any other INAH. No sexual variation in neuronal size or density was observed in any INAH. Although there was a trend for INAH3 to occupy a smaller volume in homosexual men than in heterosexual men, there was no difference in the number of neurons within the nucleus based on sexual orientation.     

Persistent generalized lymphadenopathy in homosexual men: clinical,pathological and immunologic characteristics.

Eighteen homosexual men who had had lymphadenopathy in two or more extrainguinal sites for more than 5 months but had no evidence of other illnesses or infections were studied. All had extreme malaise, and 90% had additional symptoms (fever, night sweats, weight loss or gastrointestinal dysfunction). They were compared with 10 healthy homosexual and 10 healthy heterosexual male controls. The mean numbers of circulating T8 (suppressor) lymphocytes were increased equally in the two homosexual groups, but the mean number of T4 (helper) lymphocytes was decreased only in the group with lymphadenopathy. The response to testing for recall anergy was diminished in both homosexual groups but was significantly lower in the group with lymphadenopathy. The serum immunoglobulin and complement concentrations and the numbers of circulating B lymphocytes were normal in each group. Seven of nine lymph node biopsy specimens showed characteristic hyperplasia and confluence of follicles. Thus, idiopathic persistent, generalized lymphadenopathy in homosexual men without opportunistic infections or malignant diseases appears to be a distinct syndrome; it may also be related to the acquired immune deficiency syndrome.     

Prevalence of Hepatitis δ (Delta) Virus Infection A Seroepidemiologic Study

In assessing the prevalence of hepatitis δ (delta) virus (HDV) infection in 358 patients with acute hepatitis B seen in Los Angeles between 1983 and 1985 and in 196 patients with chronic hepatitis B followed between 1980 and 1985, we found that 23% of patients with chronic and 5% of patients with acute hepatitis B were infected with HDV. Among patients with chronic hepatitis B, the prevalence of HDV infection was 73% in intravenous drug users and 14% in homosexual men. Acute coinfection with the hepatitis B virus was also more frequent in drug users (8%) than in other groups. δ-Hepatitis is a common infection in hepatitis B virus carriers in Los Angeles, particularly in drug addicts, but also in homosexual men who do not abuse drugs intravenously.     

Cross-species transmission of Giardia spp.: inoculation of beavers and muskrats with cysts of human, beaver, mouse, and muskrat origin.

Giardia cysts isolated from humans, beavers, mice, and muskrats were tested in cross-species transmission experiments for their ability to infect either beavers or muskrats. Giardia cysts, derived from multiple symptomatic human donors and used for inoculation of beavers or muskrats, were shown to be viable by incorporation of fluorogenic dyes, excystation, and their ability to produce infections in the Mongolian gerbil model. Inoculation of beavers with 5 x 10(5) Giardia lamblia cysts resulted in the infection of 75% of the animals (n = 8), as judged by the presence of fecal cysts or intestinal trophozoites at necropsy. The mean prepatent period was 13.1 days. An infective dose experiment, using 5 x 10(1) to 5 x 10(5) viable G. lamblia cysts collected by fluorescence-activated cell sorting, demonstrated that doses of between, less than 50, and less than 500 viable cysts were required to produce infection in beavers. Scanning electron microscopy of beaver small intestine revealed that attachment of G. lamblia trophozoites produced lesions in the microvillous border. Inoculation of muskrats with G. lamblia cysts produced infections when the dose of cysts was equal to or greater than 1.25 x 10(5). The inoculation of beavers with Giardia ondatrae or Giardia muris cysts did not produce any infection; however, the administration to muskrats of Giardia cysts of beaver origin resulted in the infection of 62% of the animals (n = 8), with a prepatent period of 5 days. Our results demonstrated that beavers and muskrats could be infected with Giardia cysts derived from humans, but only by using large numbers of cysts.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cross-species transmission of Giardia spp.: inoculation of beavers and muskrats with cysts of human, beaver, mouse, and muskrat origin

Giardia cysts isolated from humans, beavers, mice, and muskrats were tested in cross-species transmission experiments for their ability to infect either beavers or muskrats. Giardia cysts, derived from multiple symptomatic human donors and used for inoculation of beavers or muskrats, were shown to be viable by incorporation of fluorogenic dyes, excystation, and their ability to produce infections in the Mongolian gerbil model. Inoculation of beavers with 5 x 10(5) Giardia lamblia cysts resulted in the infection of 75% of the animals (n = 8), as judged by the presence of fecal cysts or intestinal trophozoites at necropsy. The mean prepatent period was 13.1 days. An infective dose experiment, using 5 x 10(1) to 5 x 10(5) viable G. lamblia cysts collected by fluorescence-activated cell sorting, demonstrated that doses of between, less than 50, and less than 500 viable cysts were required to produce infection in beavers. Scanning electron microscopy of beaver small intestine revealed that attachment of G. lamblia trophozoites produced lesions in the microvillous border. Inoculation of muskrats with G. lamblia cysts produced infections when the dose of cysts was equal to or greater than 1.25 x 10(5). The inoculation of beavers with Giardia ondatrae or Giardia muris cysts did not produce any infection; however, the administration to muskrats of Giardia cysts of beaver origin resulted in the infection of 62% of the animals (n = 8), with a prepatent period of 5 days. Our results demonstrated that beavers and muskrats could be infected with Giardia cysts derived from humans, but only by using large numbers of cysts.(ABSTRACT TRUNCATED AT 250 WORDS)     

Sexual behaviour of young and middle aged men in England and Wales.

Establishing patterns of sexual behaviour is essential in predicting the future spread of HIV. The sexual behaviour patterns of a randomly selected sample of 480 white men aged 15 to 49 were obtained by interview and analysed in relation to age, social class, and area of residence. Over half of the men had first had intercourse before the age of 18 and over three quarters had done so before the age of 20. Age at first intercourse tended to be lower in more recent birth cohorts and in social classes III, IV, and V. Men in earlier birth cohorts tended to have had fewer heterosexual partners, both regular and casual, than those born more recently, but there were no social class or regional differences in the number of partners. Eight of the 480 men (1.7%, 95% confidence interval 1.1 to 2.3%) stated that they had had homosexual intercourse, four of whom had had one casual homosexual partner. Only one man had had more than 25 homosexual partners. The number of men having had homosexual intercourse was lower than is widely thought. When possible, data were checked with national data or other surveys and thought to be accurate. The difficulties in collecting data of this nature are discussed.     

Risk factors for infection with human immmunodeficiency virus among European expatriates in Africa.

The pattern of cases of AIDS in Belgium suggests that Europeans infected with human immunodeficiency virus (HIV) acquired the infection in Africa. The prevalence of infection was assessed in Belgian advisers and European expatriates and risk factors for infection defined in a case-control study of expatriate men. Fifteen (1.1%) of 1401 Belgian advisers working in Africa and 41 (0.9%) of 4564 European expatriates living in Africa, were positive for antibody to HIV in a voluntary screening programme in Belgium. Among subjects with antibody to HIV the ratio of men to women was 3:1. These subjects did not have a history of intravenous drug abuse or blood transfusion and only one was homosexual. In a case-control study of 33 expatriate men who had antibody to HIV and 119 controls the men with antibody reported significantly more female sexual partners, who were more commonly local; and significantly more sexual contact with prostitutes in Africa. They had a significantly higher prevalence of history of sexually transmitted disease and had received significantly more injections by unqualified staff in Africa during the previous five years. No specific sexual practices were associated with having antibody to HIV. After multivariate analysis sexual contact with local women (adjusted odds ratio 14.7; 95% confidence interval 2.81 to 76.9), sexual contact with prostitutes (adjusted odds ratio 10.8 (1.6 to 71.9), and injections by unqualified staff (adjusted odds ratio 13.5 (3.7 to 49.8) remained independent risk factors for infection. European expatriates in Africa were at increased risk from infection with HIV and were a means of introducing HIV into the heterosexual population in Europe. Transmission from women to men by vaginal intercourse seemed to be the most probable route of infection.     

Birth weight, sexual orientation and the sex of preceding siblings.

This study's first objective was to compare the mean birth weights of homosexual and heterosexual men and women. Its second objective was to investigate whether prior male and female fetuses have different effects on the birth weight of subsequent fetuses. The subjects were 3229 adult men and women (the probands), who weighed at least 2500 g at birth, and whose mothers knew the sex of the child (or fetus) for each pregnancy prior to the proband. Information on birth weight, maternal gravidity and other demographic variables was reported on questionnaires completed by the probands' mothers. The results confirmed earlier reports that boys with older brothers weigh less at birth than boys with older sisters, but they did not confirm reports that girls with older brothers weigh less than girls with older sisters. The results did not show across-the-board differences in the mean birth weights of homosexual versus heterosexual women or homosexual versus heterosexual men. However, the homosexual males with older brothers weighed about 170 g less at birth than the heterosexual males with older brothers. It is suggested that this pattern of results may reflect a maternal immune response to Y-linked minor histocompatibility antigens (H-Y antigens). According to this hypothesis, when the maternal immune response is mild, it produces only a slightly reduced birth weight, but when it is stronger, it produces a markedly reduced birth weight as well as an increased probability of homosexuality.     

Is risk of Kaposi's sarcoma in AIDS patients in Britain increased if sexual partners came from United States or Africa?

OBJECTIVE--To determine whether the risk of Kaposi''s sarcoma in patients with AIDS is increased by sexual contact with groups from abroad with a high incidence of Kaposi''s sarcoma. DESIGN--Analysis of risk of Kaposi''s sarcoma in patients with AIDS, according to country of origin of their sexual partners. SETTING--United Kingdom. PATIENTS--2830 patients with AIDS reported to the Communicable Disease Surveillance Centre and the Communicable Disease (Scotland) Unit up to March 1990, of whom 566 had Kaposi''s sarcoma. MAIN OUTCOME MEASURES--Percentage of patients with AIDS who had Kaposi''s sarcoma. RESULTS--537 of 2291 homosexual or bisexual men (23%) with AIDS had Kaposi''s sarcoma; 10% (14/135) of the men and women who acquired HIV by heterosexual contact had Kaposi''s sarcoma. None of the 316 subjects who acquired HIV through non-sexual routes had Kaposi''s sarcoma. Kaposi''s sarcoma was more common among homosexual men whose likely source of infection included the United States (171/551, 31%) or Africa (9/34, 26%) than among those infected in the United Kingdom (119/625, 19%) (p less than 0.05). CONCLUSION--The data suggest that Kaposi''s sarcoma is caused by a sexually transmissible agent which was introduced into the British homosexual population mainly from the United States [corrected].     

Prevalence of HIV antibody in high and low risk groups in England. Public Health Laboratory Service Working Group.

Most studies of the spread of HIV infection have centred on homosexuals and intravenous drug users. To estimate the extent of infection in different groups, including heterosexuals, the prevalence of HIV antibody was studied in 34,222 subjects tested with consent between October 1986 and December 1987 in England. These included subjects in high risk groups for HIV infection, heterosexuals with partners in the high risk groups and heterosexuals with multiple partners or with no identifiable risk factors. The prevalence was highest in homosexual or bisexual men in London (15.1%; 213/1412), being 4.0% (146/3607) outside London. The yearly incidence of infection in 632 homosexual or bisexual men without HIV antibody when retested during the study period was 3%. Among intravenous drug users the prevalence of HIV antibody was 5.7% (36/633) in London and 1.5% (39/2562) outside. Of 3272 heterosexual subjects tested, whose partner was in a risk group, eight of 515 (1.6%) in London and six of 2757 (0.2%) outside were positive for the antibody. Among 20,455 heterosexuals with a history of multiple partners or with no declared risk, only six subjects with HIV antibody were identified, two of whom had been infected abroad. Heterosexual spread of infection in England is evidently still largely confined to subjects whose partner has an identifiable risk.     

Intestinal parasites in metropolitan Toronto day-care centres.

In 1981, 900 children (aged 3 months to 10 years) and 146 staff attending 22 day-care centres in metropolitan Toronto chosen at random provided a stool specimen in a survey for intestinal parasites. Of the children, 4% to 36% were infected in 20 of 22 centres. Overall, 19% of the children and 14% of the staff had intestinal parasites: 8.6% and 4.0% respectively had Dientamoeba fragilis, and 7.8% and 2.0% respectively had Giardia lamblia. The highest prevalence of dientamebiasis was in the 7- to 10-year-olds, whereas giardiasis was detected most frequently in the 6-year-olds. Infection with intestinal parasites was not correlated with age, sex, duration in the day-care centre, dog ownership, travel history, gastrointestinal symptoms or the proportion of children in the day-care centre who were born in less developed countries. Immigrant children and children of parents born in industrialized countries (including Canada) were more likely to be infected than were children born in Canada of parents from the developing world. Dientamebiasis was associated with cat ownership. Thus, intestinal protozoa--in particular, D. fragilis and G. lamblia--are endemic in Toronto day-care centres.     

Person-to-person transmission of Giardia lamblia in day-care nurseries.

In an outbreak of giardiasis at two day-care nurseries in metropolitan Toranto Giardia lamblia appeared to be transmitted person to person. No common source of infection could be found. The proportions of children infected in the two nurseries were 39% and 17%; infection was spread to 7% and 23% of their household contacts. Of the infected children and household contacts 26% and 30% respectively of those for whom detailed information could be obtained were symptomatic. Canadian children were more likely to be infected and symptomatic than were immigrant children attending the nurseries. The most susceptible ages for infection were 1 to 3 years. The results of this study suggest that all children in day-care nurseries who are infected with G. lamblia should be treated, regardless of whether they are symptomatic.     

Evocability of a slight positive oestrogen feedback action on LH secretion in castrated and oestrogen-primed men.

Orchidectomized heterosexual men suffering from prostatic cancer with suppressed serum LH values by oestrogen priming exhibited a slight, but significant surge of LH secretion following oestrogen injection. In contrast, orchidectomized and oestrogen-primed heterosexual men with unsuppressed serum LH levels as well as intact heterosexual men did not display any positive oestrogen feedback action on LH secretion, as it was observed in intact homosexual men.