Partner choice in genito-genital rubbing among female bonobos (Pan paniscus) is highly dependent on physical proximity.

Sociosexual interactions of non-human primates have multiple functions, and information on partner choice could help us to determine the major purpose of these behaviors. Female bonobos (Pan paniscus) frequently engage in genito-genital (GG) rubbing, which is categorized as a sociosexual behavior. The functions of GG rubbing may vary across allopatric bonobo populations, especially in relation to its use in social bonding. Thus, we aimed to examine the use of GG rubbing in the formation and maintenance of social bonds by examining partner choice in this context in the habituated bonobo population at Wamba, Democratic Republic of the Congo. We examined the effect of female age (and correlated dominance rank) on the proportion of solicited GG rubbing, and the effects of age difference, proximity index, and grooming index on the successful GG rubbing occurrences. Our results showed that female age significantly affected the proportion of solicited GG rubbing, indicating that older and higher-ranking females solicited this activity more frequently. Individuals of female-female dyads who were close in age and dominance rank frequently engaged in GG rubbing. The more the females in a dyad were in physical proximity, the more they engaged in GG rubbing. No correlation was observed between grooming and GG rubbing. These results indicate that partner choice in GG rubbing is highly dependent on physical proximity, and suggest that characteristics of female gregariousness might be important with respect to this choice among bonobos.

Caracterización sociodemográfica y perfil clínico de pacientes con diagnóstico de neurosífilis en una población de Bogotá, Colombia / Socio-demographic characterization and clinical profile of patients diagnosed with neurosyphilis in a population of Bogotá, Colombia

RESUMEN INTRODUCCIÓN: La neurosífilis se asocia con una serie de signos y síntomas que pueden aparecer luego de 10 a 30 años de la primoinfección; es más frecuente en pacientes con VIH, conductas homosexuales y adultos de género masculino. Es una enfermedad tratable, cuya incidencia viene en descenso notorio tras el advenimiento de la terapia antibiótica de fácil acceso, lo que la convierte en un problema de salud pública a escala mundial. OBJETIVO: Determinar la prevalencia y las variables sociodemográficas, clínicas y paraclínicas de los pacientes con diagnóstico de neurosífilis tratados en la Unidad de Servicios de Salud Occidente de Kennedy (USSOK), Bogotá, Colombia, entre el 2014 y el 2018. PACIENTES Y MÉTODOS: Se llevó a cabo un estudio observacional analítico de corte transversal, retrospectivo, en el que se evaluó a pacientes con diagnóstico de neurosífilis que recibieron manejo en la USS Occidente Kennedy durante 2014-2018. Para tal fin se incluyó a mayores de 18 años con diagnóstico de neurosífilis, y se hizo estudio de líquido cefalorraquídeo, pruebas no treponémicas en las que se usó el VDRL y pruebas treponémicas en las cuales se empleó FTA-Abs. RESULTADOS: Se diagnosticaron 55 casos de neurosífilis durante el periodo estudiado. Si se tiene en cuenta el número total de pacientes atendidos (8244), la prevalencia calculada correspondió a 0,66 %. CONCLUSIONES: En nuestro medio, la prevalencia de neurosífilis (0,6 %) es mayor a la reportada en poblaciones de altos ingresos económicos (0,4 %). El perfil sociodemográfico de pacientes con diagnóstico de neurosífilis de una población de bajos recursos se caracteriza por: adultos en la sexta década de la vida, sexo masculino e inmunocompetentes.

SUMMARY INTRODUCTION: Neurosyphilis is associated with a series of signs and symptoms that may appear 10 to 30 years after the first infection; it is more frequent in patients with HIV, homosexual behavior and male adults. It is a treatable disease, whose incidence comes in a noticeable descent after the advent of easily accessible antibiotic therapy, which makes it a public health problem worldwide. OBJECTIVE: To determine the prevalence, sociodemographic, clinical and paraclinical variables of patients diagnosed with Neurosyphilis treated in the Kennedy West Health Services Unit (USSOK) between 2014-2018 PATIENTS AND METHODS: An observational, cross-sectional, retrospective, observational study was carried out in which patients diagnosed with Neurosyphilis who received management at the USS West Kennedy during 2014-2018 were evaluated. They were older than 18 years, with a diagnosis of Neurosyphilis. Cerebrospinal fluid study, non-treponemal tests where VDRL was used and treponemal tests using FTA-Abs RESULTS: 55 cases of neurosyphilis were diagnosed during the period studied. Taking into account the total number of patients treated (8244), the calculated prevalence corresponded to 0.66 % CONCLUSIONS: The prevalence of Neurosyphilis in our environment (0.6 %) is higher than that reported in high income populations (0.4 %). The sociodemographic profile of patients diagnosed with neurosyphilis from a low-income population is characterized by: adults in the sixth decade of life, male and immunocompetent.

[Homosexual behavior and related factors among married men who have sex with men in Mianyang city, Sichuan province].

Objective: To understand the homosexual behavior and related factors among married MSM in Mianyang city. Methods: Between January and October in 2017, a snowball sampling method was adopted to carry out cross-sectional survey through questionnaires plus HIV testing among those MSM in Mianyang city. Logistic regression model was used to analyze homosexual behaviors and related factors among married MSM under study. Statistical analysis was used by EpiData 3.1 and SPSS 19.0 software. Results: A total of 234 MSM participated in this survey. The overall rate of homosexual behavior in these married MSM appeared as 94.9% (222/234). Rate of having anal sex behavior was 94.4% (221/234) in the past 6 months, with rate of condom use as 57.9% (128/221). HIV positive rate was 8.1% (18/222). As for the motives for homosexual behavior after marriage, 87.8% (195/222) were driven by feelings of love, 12.2% (27/222) due to 'releasing pressure'. Proportion of male sex partners would include occasional sex partners (62.2%, 138/222), stable male sex partners (26.1%, 58/222) and stable boyfriends (11.7%, 26/222). Factors from logistic regression analysis showed that homosexual behaviors were related to the factors including education level of senior high school or above vs. education level of junior middle school or below (OR=3.65, 95%CI: 1.33-9.98); local residency over one year vs. the ones having local residency less than one year (OR=23.28, 95%CI:1.67-324.89); having 10 or more friends in the MSM community vs. having below 10 friends in MSM community (OR=4.15, 95%CI: 1.28-13.43); without sex pleasure with spouse vs. having sex pleasure with spouse (OR=3.25, 95%CI: 1.22-8.62); having 2 or more anal sex partners in the past 6 months vs. having less than 2 anal sex partners in the past 6 months (OR=0.28,95%CI: 0.09-0.81). Conclusions: The rate of homosexual behavior and HIV positive rate were high among MSM in Mianyang city. Homosexual behaviors after marriage were influenced by multiple factors among MSM. The motives of homosexual behavior after marriage were driven by feelings of love, the related factors were education level of senior high school or above, local residency over one year, having 10 or more friends in the MSM community and without sex pleasure with spouse. As for the motives of these behaviors was caused by releasing pressure, the related factors was having more than 2 anal sex partners.

Homosexual behavior and related factors among married men who have sex with men in Mianyang city, Sichuan province / 中华流行病学杂志

Objective@#To understand the homosexual behavior and related factors among married MSM in Mianyang city.@*Methods@#Between January and October in 2017, a snowball sampling method was adopted to carry out cross-sectional survey through questionnaires plus HIV testing among those MSM in Mianyang city. Logistic regression model was used to analyze homosexual behaviors and related factors among married MSM under study. Statistical analysis was used by EpiData 3.1 and SPSS 19.0 software.@*Results@#A total of 234 MSM participated in this survey. The overall rate of homosexual behavior in these married MSM appeared as 94.9% (222/234). Rate of having anal sex behavior was 94.4% (221/234) in the past 6 months, with rate of condom use as 57.9% (128/221). HIV positive rate was 8.1% (18/222). As for the motives for homosexual behavior after marriage, 87.8% (195/222) were driven by feelings of love, 12.2% (27/222) due to 'releasing pressure’. Proportion of male sex partners would include occasional sex partners (62.2%, 138/222), stable male sex partners (26.1%, 58/222) and stable boyfriends (11.7%, 26/222). Factors from logistic regression analysis showed that homosexual behaviors were related to the factors including education level of senior high school or above vs. education level of junior middle school or below (OR=3.65, 95%CI: 1.33-9.98); local residency over one year vs. the ones having local residency less than one year (OR=23.28, 95%CI:1.67-324.89); having 10 or more friends in the MSM community vs. having below 10 friends in MSM community (OR=4.15, 95%CI: 1.28-13.43); without sex pleasure with spouse vs. having sex pleasure with spouse (OR=3.25, 95%CI: 1.22-8.62); having 2 or more anal sex partners in the past 6 months vs. having less than 2 anal sex partners in the past 6 months (OR=0.28,95%CI: 0.09-0.81).@*Conclusions@#The rate of homosexual behavior and HIV positive rate were high among MSM in Mianyang city. Homosexual behaviors after marriage were influenced by multiple factors among MSM. The motives of homosexual behavior after marriage were driven by feelings of love, the related factors were education level of senior high school or above, local residency over one year, having 10 or more friends in the MSM community and without sex pleasure with spouse. As for the motives of these behaviors was caused by releasing pressure, the related factors was having more than 2 anal sex partners.

Hormonal contraceptive affects heterosexual but not homosexual behavior in free-ranging female Japanese macaques over 17 mating seasons.

We assessed the effect of a progestin-based contraceptive treatment (chlormadinone acetate) on female heterosexual and homosexual behaviors in a free-ranging group of Japanese macaques (Macaca fuscata) living at Arashiyama-Kyoto, Central Japan. The data included estimated intensity of fertility cues, sexual solicitations and mounting behaviors collected daily during 17 consecutive mating seasons (1995-2012) from 159 females. Females that were on contraception: (1) exhibited less intense cues of putative fertility and for shorter periods; (2) were solicited by fewer males, and those males that did solicit them did so less often (i.e., lower heterosexual attractivity); (3) solicited fewer males and when they did perform sexual solicitations they did so less often (i.e., lower heterosexual proceptivity); (4) engaged in shorter heterosexual consortships with fewer male partners (i.e., lower heterosexual receptivity), compared with females that were not on contraception. In contrast, contraceptive treatment had no significant effect on the prevalence, occurrence, frequency, or duration of female homosexual behaviors. Even though heterosexual and homosexual behaviors can both be considered sexual in character and under hormonal control, our results suggested they are, to some extent, dissociable. Because females engaging in homosexual interactions showed less intense cues of putative fertility than those engaging in heterosexual interactions, regardless of contraceptive treatment, we argued that the hormonal threshold required for the expression of heterosexual behavior by females was associated with elevated sex hormones levels compared to homosexual behavior. We discussed the hormonal correlates of sexual behavior and partner preferences in Japanese macaques.

Homosexual Behavior Between Male Spider Monkeys (Ateles geoffroyi).

Homosexual behavior is defined as genital contact or genital manipulation between same-sex individuals. In nonhuman primates, it may regulate social relationships by serving as a means of reconciliation, tension alleviation, or alliance formation. Grappling is a rare and complex behavior, which most frequently occurs between same-sex individuals of the genus Ateles and can include mutual manipulation of the genitalia. Here we report three cases of penile-anal intromission during grappling between wild male spider monkeys living in the natural protected area of Otoch Ma'ax Yetel Kooh, Mexico. In all the observed cases, the same adult male was the actor. To our knowledge, this is the first report of penile-anal intromission between males in any New World primate species.

Epidemiological characteristics of students with HIV/AIDS in Hangzhou / 预防医学

Objective To explore the epidemiological characteristics of young students with HIV/AIDS in Hangzhou and to provide scientific basis for AIDS prevention and control in school settings. Methods Data on HIV/AIDS patients was collected from HIV Comprehensive Prevention and Control Information System, and retrospective survey was conducted to those who were students and whose current residential address was Hangzhou. Results A total of 132 HIV/AIDS student cases were surveyed. The average age was (21.42±2.65) years, and 98.48％ were male. The proportion of homosexual transmission was 83.33％. Before positive confirmation, 55.45％ had homosexual partners both from students and non-students, 90.91％ had temporary sexual behavior, five cases had heterosexually fixed partners and two cases had heterosexually temporary partners.The proportions of condom use in all types of sexual partners ranged from 0.00％-50.00％. Seventy-two (54.55％) HIV/AIDS student cases thought they were impossible to be infected by HIV. Only 23.48％ of cases did HIV antibody test before positive confirmation. The proportion of HARRT was 80.30％. The proportion of co-infected with syphilis was 18.03％. Conclusion Homosexual behavior is the main route of transmission for HIV infection among young students in Hangzhou. Dangerous behaviors are prevalent, and the situation of AIDS prevention and control among students is severe.

A study on male homosexual behavior.

INTRODUCTION: Male homosexual behavior carries a high risk of transmitting sexually transmitted infections (STIs). Ignorance regarding the associated high risk, indulgence inspite of no natural homosexual orientation and not using protective barrier methods can affect the sexual health of adolescents and adults. AIM: (1) To assess the proportion of men who have sex with men (MSM) having a natural homosexual orientation compared to those who had acquired the homosexual behavior initially under various circumstances (such as due to certain misconceptions, fear of having heterosexual contact, peer pressure, and influence of alcohol). (2) To assess the level of awareness regarding increased risk of transmission of STIs associated with homosexual behavior and regarding protective barrier methods. MATERIALS AND METHODS: After obtaining consent from the subjects, questionnaire - based interview used for obtaining data for this observational (cross-sectional) study. RESULTS: (1) Of the 50 subjects, only about 25% had interest in homosexual behavior prior to initial episode. (2) About 50% subjects indulged in homosexual behavior due to lack/fear of having heterosexual contact. (3) About 60% subjects believed that homosexual behavior carried relatively lower risk of acquiring STIs and 68% subjects have had unprotected contact. (4) About 70% subjects had only acquired this behavior and nearly 60% subjects were interested in heterosexual marriage and not interested in further homosexual behavior. CONCLUSION: (1) Homosexuality is a natural orientation in some and an acquired behavior in the rest. (2) If homosexual behavior is acquired, due to misconceptions, then imparting sex education and awareness regarding involved risks, and the importance of protective barrier methods will prevent ignorance driven behavior. For those with natural homosexual orientation, the importance of protective barrier methods in homosexual behavior needs emphasis.

Prenatal Hypoxia Ischemia Increases Male Rat Sexual Behavior.

INTRODUCTION: Research consistently indicates an association between prenatal hypoxia-ischemia (HI) and mortality and chronic neurological diseases in newborns. HI can cause permanent effects, including mental retardation, motor impairment, learning disabilities, epilepsy, and cerebral palsy. Moreover, little is known about the relationship between HI and sexual behavior. AIMS: The aims of this study are to examine whether HI is associated with changes in sexual behavior. METHODS: HI was induced by clamping the uterine arteries of pregnant rats. The arteries were clamped for 45 minutes on the 18th day of gestation (HI group). Shams received laparotomy and anesthesia only. Pups were born at term. At 90 days of age, sexual behavior was evaluated. Statistical analysis was performed using two-way analysis of variance and post hoc Bonferonni correction. MAIN OUTCOME MEASURES: The main outcome measures of sexual response were standard sexual behavior, homosexual behavior, and sexual attempt on nonreceptive females. RESULTS: The stimulatory effect of HI on male rat sexual behavior has been shown in various experimental models; these animals showed reduced mount, intromission and ejaculation latencies; increased copulatory efficiency; and homosexual mounting. Additionally, there was an increase in fighting in trying to mount an unreceptive female. CONCLUSION: Our results indicate that HI had a long-term effect on sexual behavior despite exhibiting motor skill impairment. Accordingly, injuries during the fetal period may cause behavioral problems in adulthood.

Effect of Female-Biased Sex Ratios on Female Homosexual Behavior in Japanese Macaques: Evidence for the "Bisexual Preference Hypothesis".

We aimed to explain the frequent and prevalent female homosexual behavior in the context of female-biased operational sex ratios (OSR) and qualified sex ratios (Q) in a free-ranging group of Japanese macaques (Macaca fuscata) living at Arashiyama-Kyoto, Japan. Our data included the average availability of sexually mature males during females' putative fertile period (OSR), the ratio of sexually mature males to sexually mature females (Q), as well as heterosexual and female homosexual solicitations and consortships collected during 13 mating seasons from 136 females. Our results did not support the "heterosexual deprivation hypothesis," which holds that female homosexual behavior is attributable to a shortage of male mates. Likewise, our results did not support the "lack of opposite-sex sexual competitor hypothesis," which holds that females have more access to female mates when male sexual rivals are scarce. Of the 11 predictions tested, only one yielded statistically significant results: we found that higher ratios of availability of preferred female partners to preferred male partners were associated with female homosexual consortships rather than female heterosexual consortships. This result supported the "bisexual preference hypothesis," which holds that female homosexual behavior is attributable to female preference for certain female mates relative to certain male mates. We conclude that when a female targets another female as a mate, it is an active choice for a female sexual partner over available male alternatives, rather than a by-default situation that occurs because males are not available as sexual partners, or because females are better able to access female sexual partners due to a scarcity of male sexual competitors.

Effects of perinatal period administration of clomiphene citrate in sexual behavior, organ weights and hormone concentration of Wistar male and female rats / Efeito da administração do citrato de clomifeno durante o período perinatal no comportamento sexual, peso dos órgãos e concentração hormonal de ratos Wistar machos e fêmeas

The effects of prenatal exposure to clomiphene citrate in sexual behavior, organ weight and hormone concentrations of male and female rats was evaluated. The animals received four doses of clomiphene citrate 2 mg/mL each during the prenatal period (21 days of gestation DG21) on days 1 (DN1), 2 (DN2) and 3 (DN3) after the birth of the puppies. The treatment led to the development of polycystic ovaries in 70% of the females, masculinization of female sexual behavior and changes in sexual behavior of males evidenced by the reduction in the number of ejaculations. In regards to hormone levels, a decrease in the FSH levels in male offspring was observed. It was concluded that clomiphene citrate interferes with the reproductive capacity of male and female rats and female sexual orientation when prenatally administered.

Foram investigados os efeitos da exposição perinatal ao citrato de clomifeno no comportamento sexual, peso dos órgãos e concentração hormonal de ratos machos e fêmeas. Os animais receberam quatro doses de 2 mg/mL de citrato de clomifeno, no período perinatal (21 dias de gestação DG21), nos dias 1 (DN1), 2 (DN2) e 3 (DN3) após o nascimento dos filhotes. O tratamento causou desenvolvimento de ovário policístico em 70% das fêmeas, masculinização do comportamento sexual das fêmeas e alteração do comportamento sexual dos machos evidenciado pela redução no número de ejaculações. Em relação aos níveis hormonais, observou-se diminuição de FSH na prole masculina. Concluiu-se que o citrato de clomifeno interfere na capacidade reprodutiva de ratos machos e fêmeas, e na orientação sexual de fêmeas, quando administrado perinatalmente.

Female homosexual behavior and inter-sexual mate competition in Japanese macaques: possible implications for sexual selection theory.

In this paper, we review research related to female homosexual behavior in Japanese macaques (Macaca fuscata), including our 20-year program of research on this species. Multiple lines of evidence indicate that female homosexual behavior in this species is sexually motivated. In contrast, many sociosexual hypotheses have been tested in relation to female homosexual behavior in Japanese macaques, but none have been supported. Female Japanese macaques sometimes engage in same-sex sexual activity even when motivated opposite-sex alternatives are available. Within this context of mate choice, males compete inter-sexually for opportunities to copulate with females above and beyond any intra-sexual competition that is required. Anecdotal evidence suggests that inter-sexual competition for female sexual partners has been observed in a number of other species, including humans. At present it is unclear whether inter-sexual competition for sexual partners influences patterns of reproduction. Our understanding of sexual selection and the evolution of mating systems may be improved by investigating whether inter-sexual mate competition influences the acquisition and maintenance of reproductive partners in those species in which such interactions occur.

Orientación sexual en adolescentes y jóvenes mexicanos de 12 a 29 años de edad / Sexual orientation among 12 to 29 year-old mexican adolescent and youths

Los objetivos del artículo fueeron describir la prevalencia de identidad no heterosexual y pronosticar su presencia o ausencia con datos de la segunda Encuesta Nacional de la Juventud (ENJUVE, 2005). En una muestra probabilística de 25.630 mexicanos de doce a diecinueve años de ambos sexos. La prevalencia de orientación no heterosexual autodefinida fue 2,5% en hombres y 1,1% en mujeres. La identidad no heterosexual es pronosticada por género masculino, haber tenido relaciones homosexuales, enamorarse de personas del mismo género y ausencia de adscripción religiosa, es decir, factores facilitadores que implican el mayor impulso de la sexualidad masculina, integrar la propia conducta homosexual, reconocer el deseo homosexual y liberarse de la condena moral que acarrea la concepción judeocristiana de la homosexualidad. Finalmente, estos datos nos hablan de una realidad que está presente para ser escuchada y respetada.

The aims of this paper were to describe the prevalence of self-defined sexual orientation, and to predict its presence or absence with the second National Survey of the Youth (ENJUVE, 2005) data. In a probability sample of 25,630 Mexicans of 12 to 29 year-old women and men, the prevalence of the non-heterosexual identity was 2.5% men and 1.1% women. The non-heterosexual identity was predicted by masculine gender, homosexual intercourses, falling in love with a person of the same gender and absence of religious adscription, that is, facilitating factors that imply the greater impulse of the masculine sexuality, to integrate the own homosexual behavior, to recognize their homosexual desire, and to free themselves from the moral condemnation that endures the Judeo-Christian conception of the homosexuality. The data show a reality to be listened to and respected.

Skewed sex ratios and female homosexual activity in Japanese macaques: An experimental analysis.

In this paper we present the results of a behavioral experiment conducted to test whether homosexual consortships and sexual solicitations among female Japanese macaques (Macaca fuscata) increase in the context of operational sex ratios that are heavily skewed towards females. The study involved a baseline period of observation on an intact social group which had a female-biased sex ratio typical of this species. During the experimental period which followed, we created a sub-group with an operational sex ratio that was heavily skewed towards females. Compared to the baseline period, females solicited significantly more same-sex individuals for sex and formed significantly more homosexual consortships during the experimental period of the study. Females did not appear to engage in homosexual activity during the study's experimental period simply because they lacked heterosexual alternatives. Instead, we suggest that an abundance of certain types of preferred, same-sex sexual partners and/or a scarcity of opposite-sex sexual competitors best account for the increased levels of female homosexual behavior observed at this time.