Sample records for male sex organ

  1. The postnatal development of the sex organs in prenatally and early postnatally irradiated male albino rats 

    E-print Network

    Ricks, Robert Clinton

    1964-01-01

    . Bagg concludes, "the results so far indicate that gamma-ray irradiation is a physical agent adapted to the study of experimentally produced developmental arrests in mammalian embryos. " Hanson (1922) reported that male albino rats which were... pregnant females were randomly placed into respective groups to await irradiation. All supsected pregnant females were palpated to confirm pregnancy before irradiation. Pregnant females received a total body dose of gamma irradiation from a cobalt-60...

  2. Male Sex Workers in Three Australian Cities

    Microsoft Academic Search

    Victor Minichiello; Rodrigo Marino; Jan Browne; Maggie Jamieson; Kirk Peterson; Brad Reuter; Kenn Robinson

    2002-01-01

    This article describes the socio-demographic and sex work characteristics of sex workers in Sydney, Melbourne, and Brisbane. A total of 185 male sex workers completed the questionnaire component of the study. The results of this study serve to debunk many of the myths surrounding the popular view of the male sex worker (MS W). The respondents in this study were

  3. Technology, normalisation and male sex work.

    PubMed

    MacPhail, Catherine; Scott, John; Minichiello, Victor

    2015-04-01

    Technological change, particularly the growth of the Internet and smart phones, has increased the visibility of male escorts, expanded their client base and diversified the range of venues in which male sex work can take place. Specifically, the Internet has relocated some forms of male sex work away from the street and thereby increased market reach, visibility and access and the scope of sex work advertising. Using the online profiles of 257 male sex workers drawn from six of the largest websites advertising male sexual services in Australia, the role of the Internet in facilitating the normalisation of male sex work is discussed. Specifically we examine how engagement with the sex industry has been reconstituted in term of better informed consumer-seller decisions for both clients and sex workers. Rather than being seen as a 'deviant' activity, understood in terms of pathology or criminal activity, male sex work is increasingly presented as an everyday commodity in the market place. In this context, the management of risks associated with sex work has shifted from formalised social control to more informal practices conducted among online communities of clients and sex workers. We discuss the implications for health, legal and welfare responses within an empowerment paradigm. PMID:25215634

  4. Sibling sex ratio and male homosexuality

    Microsoft Academic Search

    B. K. Suarez; T. R. Przybeck

    1980-01-01

    As an explanation for the increased sex ratio observed in the sibships of male homosexuals, Slater has hypothesized that the increase, itself, may be a causative factor in predisposing a male to homosexual behavior. As a test of this hypothesis, an additive and a multiplicative risk model relating male homosexuality to the sexual configuration of the homosexual's sibship were formulated

  5. Rogue Males: Sex Differences in Psychology Students

    ERIC Educational Resources Information Center

    Sander, Paul; Sanders, Lalage

    2006-01-01

    Introduction: This paper reports a preliminary study into the commitment and academic confidence of male students in undergraduate psychology, prompted by our own observations of the performance of male students and the literature on sex differences in education. Method: Using an analytical survey, level 1 psychology students at a new university…

  6. Sex hormones and the elderly male voice.

    PubMed

    Gugatschka, Markus; Kiesler, Karl; Obermayer-Pietsch, Barbara; Schoekler, Bernadette; Schmid, Christoph; Groselj-Strele, Andrea; Friedrich, Gerhard

    2010-05-01

    The objective was to describe influences of sex hormones on the male voice in an elderly cohort. Sixty-three elderly males were recruited to undergo assessment of voice parameters, stroboscopy, voice-related questionnaires, a blood draw, and an ultrasound examination of the laryngeal skeleton. The group was divided into men with normal hormonal status and men with lowered levels of sex hormones, called hypogonades. Depending on the level of androgens, voice parameters did not differ. In subjects with decreased levels of estrogens, a significant increase in mean fundamental frequency, as well as changes of highest and lowest frequency plus a shift of the frequency range could be detected. We could detect significant changes of voice parameters depending on status of estrogens in elderly males. Androgens appear to have no impact on the elderly male voice. To our knowledge, this is the first prospective study that correlates sex hormones with voice parameters in elderly men. PMID:19185460

  7. Male pygmy hippopotamus influence offspring sex ratio.

    PubMed

    Saragusty, Joseph; Hermes, Robert; Hofer, Heribert; Bouts, Tim; Göritz, Frank; Hildebrandt, Thomas B

    2012-01-01

    Pre-determining fetal sex is against the random and equal opportunity that both conceptus sexes have by nature. Yet, under a wide variety of circumstances, populations shift their birth sex ratio from the expected unity. Here we show, using fluorescence in situ hybridization, that in a population of pygmy hippopotamus (Choeropsis liberiensis) with 42.5% male offspring, males bias the ratio of X- and Y-chromosome-bearing spermatozoa in their ejaculates, resulting in a 0.4337±0.0094 (mean±s.d.) proportion of Y-chromosome-bearing spermatozoa. Three alternative hypotheses for the shifted population sex ratio were compared: female counteract male, female indifferent, or male and female in agreement. We conclude that there appears little or no antagonistic sexual conflict, unexpected by prevailing theories. Our results indicate that males possess a mechanism to adjust the ratio of X- and Y-chromosome-bearing spermatozoa in the ejaculate, thereby substantially expanding currently known male options in sexual conflict. PMID:22426218

  8. Operational sex ratio influences female preference and male–male competition in guppies

    Microsoft Academic Search

    Mullica Jirotkul

    1999-01-01

    Manipulation of the operational sex ratio (OSR) in guppies, Poecilia reticulata, causes changes in male–male competition and female mate choice. In this study OSR is defined as the number of sexually active males divided by the total number of sexually active adults of both sexes. The rate of male courtship displays decreased, and interference behaviours between males increased, at male-biased

  9. Intimate Violence in Male Same-Sex Relationships

    Microsoft Academic Search

    Jessica L. Stanley; Kim Bartholomew; Tracy Taylor; Doug Oram; Monica Landolt

    2006-01-01

    Despite findings suggesting a high prevalence of violence in male same-sex relationships, little is known about the characteristics of this violence. This study explored the general nature of male same-sex intimate violence. The sample consisted of 69 gay and bisexual men, chosen from a randomly selected community sample, who reported at least 1 violent episode in an interview exploring their

  10. Sex and Sexism: A Comparison of Male and Female Sex-Role Attitudes

    ERIC Educational Resources Information Center

    Osmond, Marie Withers; Martin, Patricia Yancey

    1975-01-01

    An examination of sex-role attitudes of both sexes revealed the following results. Males and females tend to show the least divergence over (1) macrolevel social change issues and (2) the familial roles of both sexes. They differ most over (3) extrafamilial roles of females and (4) the stereotypes of both sexes. Paper presented at the American…

  11. Sex ratio bias, male aggression, and population collapse in lizards

    E-print Network

    Alvarez, Nadir

    Sex ratio bias, male aggression, and population collapse in lizards Jean-Franc¸ois Le Galliard 20, 2005) The adult sex ratio (ASR) is a key parameter of the demography of human and other animal is regulated by intrasexual competition, which would cause more mortality or emigration in the sex

  12. Masculinity and Relationship Agreements among Male Same-Sex Couples

    Microsoft Academic Search

    Christopher W. Wheldon; Elizabeth B. Pathak

    2010-01-01

    Extradyadic sex is a significant source of risk for sexually transmitted infections (STIs) among men in same-sex relationships. Nonmonogamous sexual agreements are common among male same-sex couples and may serve as effective targets for risk reduction interventions; however, there is a dearth of research reporting on the social and cultural determinants of explicit nonmonogamous agreements. In this study, it was

  13. Variably male-biased sex ratio in a marine bird with females larger than males

    Microsoft Academic Search

    Roxana Torres; Hugh Drummond

    1999-01-01

    When the costs of rearing males and females differ progeny sex ratios are expected to be biased toward the less expensive\\u000a sex. Blue-footed booby (Sula nebouxii) females are larger and roughly 32% heavier than males, thus presumably more costly to rear. We recorded hatching and fledging\\u000a sex ratios in 1989, and fledging sex ratios during the next 5?years. In 1989,

  14. Identification of Sex-Specific Markers Reveals Male Heterogametic Sex Determination in Pseudobagrus ussuriensis.

    PubMed

    Pan, Zheng-Jun; Li, Xi-Yin; Zhou, Feng-Jian; Qiang, Xiao-Gang; Gui, Jian-Fang

    2015-08-01

    Comprehending sex determination mechanism is a first step for developing sex control breeding biotechnologies in fish. Pseudobagrus ussuriensis, one of bagrid catfishes in Bagridae, had been observed to have about threefold size dimorphism between males and females, but its sex determination mechanism had been unknown. In this study, we firstly used the amplified fragment length polymorphism (AFLP)-based screening approach to isolate a male-specific DNA fragment and thereby identified a 10,569 bp of male-specific sequence and a 10,365 bp of female-related sequence by genome walking in the bagrid catfish, in which a substantial genetic differentiation with 96.35 % nucleotide identity was revealed between them. Subsequently, a high differentiating region of 650 bp with only 70.26 % nucleotide identity was found from the corresponding two sequences, and three primer pairs of male-specific marker, male and female-shared marker with different length products in male and female genomes, and female-related marker were designed. Significantly, when these markers were used to identify genetic sex of the bagrid catfish, only male individuals was detected to amplify the male-specific marker fragment, and female-related marker was discovered to produce dosage association in females and in males. Our current data provide significant genetic evidence that P. ussuriensis has heterogametic XY sex chromosomes in males and homogametic XX sex chromosomes in females. Therefore, sex determination mechanism of P. ussuriensis is male heterogametic XX/XY system. PMID:25981673

  15. Sex guilt and males' preference for reading erotic magazines

    Microsoft Academic Search

    Thomas Schill; James Chapin

    1972-01-01

    Measured the time 27 males spent reading erotic or nonerotic magazines while ostensibly waiting to partake in an experiment. Ss then completed a forced choice Sex Guilt scale (D. Mosher), read for another 5 min., and completed a mood adjective checklist, and a double-entendre word association test (G. Galbraith). High erotic readers had significantly lower sex guilt scores than low

  16. Male-to-Female Sex Reversal in Mice Lacking Fibroblast Growth Factor 9

    Microsoft Academic Search

    Jennifer S. Colvin; Rebecca P. Green; Jennifer Schmahl; Blanche Capel; David M. Ornitz

    2001-01-01

    Fgfs direct embryogenesis of several organs, including the lung, limb, and anterior pituitary. Here we report male-to-female sex reversal in mice lacking Fibroblast growth factor 9 (Fgf9), demonstrating a novel role for FGF signaling in testicular embryogenesis. Fgf9?\\/? mice also exhibit lung hypoplasia and die at birth. Reproductive system phenotypes range from testicular hypoplasia to complete sex reversal, with most

  17. Chemosterilization of male sea lampreys, (Petromyzon marinus), does not affect sex pheromone release

    USGS Publications Warehouse

    Siefkes, Michael J.; Bergstedt, Roger A.; Twohey, Michael B.; Li, Weiming

    2003-01-01

    Release of males sterilized by injection with bisazir is an important experimental technique in management of sea lamprey (Petromyzon marinus), an invasive, nuisance species in the Laurentian Great Lakes. Sea lampreys are semelparous and sterilization can theoretically eliminate a male's reproductive capacity and, if the ability to obtain mates is not affected, waste the sex products of females spawning with him. It has been demonstrated that spermiating males release a sex pheromone that attracts ovulating females. We demonstrated that sterilized, spermiating males also released the pheromone and attracted ovulating females. In a two-choice maze, ovulating females increased searching behavior and spent more time in the side of the maze containing chemical stimuli from sterilized, spermiating males. This attraction response was also observed in spawning stream experiments. Also, electro-olfactograms showed that female olfactory organs were equally sensitive to chemical stimuli from sterilized and nonsterilized, spermiating males. Finally, fast atom bombardment mass spectrometry showed that extracts from water conditioned with sterilized and nonsterilized, spermiating males contained the same pheromonal molecule at similar levels. We concluded that injection of bisazir did not affect the efficacy of sex pheromone in sterilized males.

  18. Economic Transition, Male Competition, and Sex Differences in Mortality

    Microsoft Academic Search

    Daniel J. Kruger; Randolph M. Nesse

    2007-01-01

    Sex differences in mortality rates stem from a complex set of genetic, physiological, psychological, and social causes whose interconnections are best understood in an integrative evolutionary framework. We predicted that the transition from centrally planned to market economies in Eastern Europe inflated the discrepancy between male and female mortality rates, because economic uncertainty and increasing variation and skew in social

  19. Beyond the Bravado: Sex Roles and the Exploitive Male.

    ERIC Educational Resources Information Center

    Taubman, Stan

    1986-01-01

    Examines the tendency of men to engage in domestic violence and sexual exploitation and presents male sex-role acquisition as a process of psychosocial violence against young boys, which creates a sense of shame, powerlessness, self-alienation, isolation from others, and retaliatory rage and inhibits capacities for intimacy and mutuality.…

  20. Male choice and competition in Tetraopes tetraophthalmus : effects of local sex ratio variation

    Microsoft Academic Search

    W. S. Lawrence

    1986-01-01

    Male milkweed beetles (Tetraopes tetraophthalmus) are shown to exhibit choice between potential mates. Males, however, also exhibit direct competition for access to potential mates. These differences in male behavior are dependent on the local sex ratio, with males becoming increasingly choosy when the sex ratio is female-biased, and more competitive when the sex ratio is malebiased. Females show neither choice

  1. Motivational Influences on the Safer Sex Behavior of Agency-based Male Sex Workers

    Microsoft Academic Search

    Michael D. Smith; David W. Seal

    2008-01-01

    Although indoor male sex workers (MSWs) have been found to engage in lower rates of HIV risk behavior with clients than street-based\\u000a MSWs, few studies have examined the motivations behind such practices. We interviewed 30 MSWs working for the same escort\\u000a agency regarding their safer sex practices with clients and their reasons for these. As in other research, MSWs reported

  2. The use of the Internet by gay and bisexual male escorts: sex workers as sex educators.

    PubMed

    Parsons, J T; Koken, J A; Bimbi, D S

    2004-11-01

    While prior studies have targeted street-based male sex workers as potential vectors of disease transmission, the number of men who work independently through Internet chat-rooms and other online endeavors has steadily increased. It is likely that these men differ substantially from their street-based counterparts in terms of sexual risk behaviors with their clients. The purpose of this study was to explore the ways in which the Internet has impacted the work of male escorts and their sexual practices with clients. Semi-structured qualitative interviews and quantitative surveys were administered to 46 such men. Less than half the men reported unprotected anal sex with clients. The qualitative data lend support to this finding, in that the majority talked about refusing any unsafe sex with clients, and many reported taking the extra step of educating their clients about the dangers of risky sex. Some of the escorts described the methods used to incorporate safer sex practices into sessions with their clients. Internet-based male escorts can play an important role as potential sex educators on the front lines of the fight against HIV and other sexually transmitted infections. PMID:15511734

  3. Racial Disparities in HIV Seroprevalence Among Male Street Sex Workers

    Microsoft Academic Search

    Larry Morton

    2010-01-01

    This dissertation examined whether racial disparities in HIV\\/AIDS between African American and Caucasian male street sex workers (MSSWs) existed and, if so, what were the possible reasons for these disparities. African American MSSWs were significantly more likely to report being HIV\\/AIDS-positive. However, when included in binary logistic models, the relationship between HIV risk factors (of syphilis and sexual assault) and

  4. Sperm counts and sperm sex ratio in male infertility patients.

    PubMed

    Eisenberg, Michael L; Murthy, Lata; Hwang, Kathleen; Lamb, Dolores J; Lipshultz, Larry I

    2012-09-01

    In recent years, investigators have noted a trend toward a declining proportion of male births in many industrialized nations. While men bear the sex-determining chromosome, the role of the female partner as it pertains to fertilization or miscarriage may also alter the gender ratio. We attempted to determine a man's secondary sex ratio (F1 generation) by directly examining the sex chromosomes of his sperm. We examined our male infertility clinic database for all men who had undergone a semen fluorescence in situ hybridization (FISH). Patient demographic and semen parameters were recorded. Chi-squared analysis was used to compare gender ratios (Y chromosomes/total chromosomes). Multivariable logistic regression was used to predict the odds of possessing a Y-bearing sperm after accounting for demographic and semen parameters. A total of 185 men underwent sperm FISH. For the entire cohort, the proportion of Y chromosome-bearing sperm was 51.5%. Men with less than five million motile sperm had a significantly lower proportion of Y chromosome-bearing sperm (50.8%) compared to men with higher sperm counts (51.6%; P=0.02). After multivariable adjustment, a higher sperm concentration, total motile sperm count and semen volume significantly increased the odds of having a Y chromosome-bearing sperm (P<0.01). As a man's sperm production declines, so does the proportion of Y chromosome-bearing sperm. Thus, a man's reproductive potential may predict his ability to sire male offspring. PMID:22842703

  5. Radiofrequency electromagnetic fields; male infertility and sex ratio of offspring.

    PubMed

    Baste, Valborg; Riise, Trond; Moen, Bente E

    2008-01-01

    Concern is growing about exposure to electromagnetic fields and male reproductive health. The authors performed a cross-sectional study among military men employed in the Royal Norwegian Navy, including information about work close to equipment emitting radiofrequency electromagnetic fields, one-year infertility, children and sex of the offspring. Among 10,497 respondents, 22% had worked close to high-frequency aerials to a "high" or "very high" degree. Infertility increased significantly along with increasing self-reported exposure to radiofrequency electromagnetic fields. In a logistic regression, odds ratio (OR) for infertility among those who had worked closer than 10 m from high-frequency aerials to a "very high" degree relative to those who reported no work near high-frequency aerials was 1.86 (95% confidence interval (CI): 1.46-2.37), adjusted for age, smoking habits, alcohol consumption and exposure to organic solvents, welding and lead. Similar adjusted OR for those exposed to a "high", "some" and "low" degree were 1.93 (95% CI: 1.55-2.40), 1.52 (95% CI: 1.25-1.84), and 1.39 (95% CI: 1.15-1.68), respectively. In all age groups there were significant linear trends with higher prevalence of involuntary childlessness with higher self-reported exposure to radiofrequency fields. However, the degree of exposure to radiofrequency radiation and the number of children were not associated. For self-reported exposure both to high-frequency aerials and communication equipment there were significant linear trends with lower ratio of boys to girls at birth when the father reported a higher degree of radiofrequency electromagnetic exposure. PMID:18415687

  6. How to make a sexy snake: estrogen activation of female sex pheromone in male red-sided garter snakes.

    PubMed

    Parker, M Rockwell; Mason, Robert T

    2012-03-01

    Vertebrates indicate their genetic sex to conspecifics using secondary sexual signals, and signal expression is often activated by sex hormones. Among vertebrate signaling modalities, the least is known about how hormones influence chemical signaling. Our study species, the red-sided garter snake (Thamnophis sirtalis parietalis), is a model vertebrate for studying hormonal control of chemical signals because males completely rely on the female sex pheromone to identify potential mates among thousands of individuals. How sex hormones can influence the expression of this crucial sexual signal is largely unknown. We created two groups of experimental males for the first experiment: Sham (blank implants) and E2 (17?-estradiol implants). E2 males were vigorously courted by wild males in outdoor bioassays, and in a Y-maze E2 pheromone trails were chosen by wild males over those of small females and were indistinguishable from large female trails. Biochemically, the E2 pheromone blend was similar to that of large females, and it differed significantly from Shams. For the second experiment, we implanted males with 17?-estradiol in 2007 but removed the implants the following year (2008; Removal). That same year, we implanted a new group of males with estrogen implants (Implant). Removal males were courted by wild males in 2008 (implant intact) but not in 2009 (removed). Total pheromone quantity and quality increased following estrogen treatment, and estrogen removal re-established male-typical pheromone blends. Thus, we have shown that estrogen activates the production of female pheromone in adult red-sided garter snakes. This is the first known study to quantify both behavioral and biochemical responses in chemical signaling following sex steroid treatment of reptiles in the activation/organization context. We propose that the homogametic sex (ZZ, male) may possess the same targets for activation of sexual signal production, and the absence of the activator (17?-estradiol in this case) underlies expression of the male phenotype. PMID:22323194

  7. [Sex chromosome aberration screening among male psychiatric patients (author's transl)].

    PubMed

    Trixler, M; Kosztolányl, G; Méhes, K

    1976-04-30

    The authors report of sex chromosome aberration screenings among the patients of the male psychiatric department, University Medical School, Pecs. 310 patients were investigated. The X-chromatin was detected in buccal smears with thionin-staining and the Y-chromatin in peripheric blood smears with quinacrin-staining by the help of fluorescentoptical technique. Two Klinefelter-patients and one YY-patient were diagnostized. The Klinefelter-patients were psychopaths and mentally subnormal, the YY-patient was a paranoid schizophrenic. The incidence of Klinefelter syndrome is 0.64%, that of the YY syndrome is 0.32%. Mental relations of sex chromosome aberrations are discussed in detail. PMID:962577

  8. Male sex workers: practices, contexts, and vulnerabilities for HIV acquisition and transmission.

    PubMed

    Baral, Stefan David; Friedman, M Reuel; Geibel, Scott; Rebe, Kevin; Bozhinov, Borche; Diouf, Daouda; Sabin, Keith; Holland, Claire E; Chan, Roy; Cáceres, Carlos F

    2015-01-17

    Male sex workers who sell or exchange sex for money or goods encompass a very diverse population across and within countries worldwide. Information characterising their practices, contexts where they live, and their needs is limited, because these individuals are generally included as a subset of larger studies focused on gay men and other men who have sex with men (MSM) or even female sex workers. Male sex workers, irrespective of their sexual orientation, mostly offer sex to men and rarely identify as sex workers, using local or international terms instead. Growing evidence indicates a sustained or increasing burden of HIV among some male sex workers within the context of the slowing global HIV pandemic. Several synergistic facilitators could be potentiating HIV acquisition and transmission among male sex workers, including biological, behavioural, and structural determinants. Criminalisation and intersectional stigmas of same-sex practices, commercial sex, and HIV all augment risk for HIV and sexually transmitted infections among male sex workers and reduce the likelihood of these people accessing essential services. These contexts, taken together with complex sexual networks among male sex workers, define this group as a key population underserved by current HIV prevention, treatment, and care services. Dedicated efforts are needed to make those services available for the sake of both public health and human rights. Evidence-based and human rights-affirming services dedicated specifically to male sex workers are needed to improve health outcomes for these men and the people within their sexual networks. PMID:25059939

  9. Male gametocyte fecundity and sex ratio of a malaria parasite, Plasmodium mexicanum

    E-print Network

    Schall, Joseph J.

    Male gametocyte fecundity and sex ratio of a malaria parasite, Plasmodium mexicanum A. T. NEAL March, 28 April and 10 May 2011; accepted 11 May 2011) SUMMARY Evolutionary theory predicts that the sex and combine with female gametes. Despite the importance of male gametocyte fecundity for sex ratio theory

  10. The Male Sex Pheromone of the Butterfly Bicyclus anynana: Towards an Evolutionary Analysis

    Microsoft Academic Search

    Caroline M. Nieberding; Helene de Vos; Maria V. Schneider; Jean-Marc Lassance; Natalia Estramil; Jimmy Andersson; Joakim Bång; Erik Hedenström; Christer Löfstedt; Paul M. Brakefield

    2008-01-01

    Background: Female sex pheromones attracting mating partners over long distances are a major determinant of reproductive isolation and speciation in Lepidoptera. Males can also produce sex pheromones but their study, particularly in butterflies, has received little attention. A detailed comparison of sex pheromones in male butterflies with those of female moths would reveal patterns of conservation versus novelty in the

  11. The Male Sex Pheromone of the Butterfly Bicyclus anynana: Towards an Evolutionary Analysis

    Microsoft Academic Search

    Caroline M. Nieberding; Helene de Vos; Maria V. Schneider; Jean-Marc Lassance; Natalia Estramil; Jimmy Andersson; Joakim Bång; Erik Hedenström; Christer Löfstedt; Paul M. Brakefield; Michael Somers

    2008-01-01

    BackgroundFemale sex pheromones attracting mating partners over long distances are a major determinant of reproductive isolation and speciation in Lepidoptera. Males can also produce sex pheromones but their study, particularly in butterflies, has received little attention. A detailed comparison of sex pheromones in male butterflies with those of female moths would reveal patterns of conservation versus novelty in the associated

  12. The use of the Internet by gay and bisexual male escorts: sex workers as sex educators

    Microsoft Academic Search

    J. T. Parsons; J. A. Koken; D. S. Bimbi

    2004-01-01

    While prior studies have targeted street-based male sex workers as potential vectors of disease transmission, the number of men who work independently through Internet chat-rooms and other online endeavors has steadily increased. It is likely that these men differ substantially from their street-based counterparts in terms of sexual risk behaviors with their clients. The purpose of this study was to

  13. Sex, eyes, and vision: male/female distinctions in ophthalmic disorders.

    PubMed

    Eisner, Alvin

    2015-02-01

    There is growing recognition: (1) that sex (male and female) and sex hormones (androgens and estrogens) are important for physiologic functions outside those pertaining expressly to reproduction, and (2) that both classes of sex hormones are active in both sexes, and moreover are produced locally in non-gonadal tissues throughout the body. The visual system, in addition to being of tremendous inherent importance, is unique in a very distinctive way; it possesses an organ - the eye - having a window allowing its interior to be examined with exquisite precision and control in both laboratory and clinical settings. Plus, many diseases manifest in the eye or are exclusive to the eye. This special issue of Current Eye Research contains 12 review articles, each addressing a different topical area important for Sex, Eyes, and Vision: Male/Female Distinctions in Ophthalmic Disorders. Of course, the distinctions between topical areas are blurred, and the overlap between the various lines of knowledge and investigation likewise is substantial. Eye diseases can be both neurodegenerative and involve altered blood flow, for instance. In fact, the thematic overlap is greater yet, in that the articles for this special issue address matters of interest to clinicians and scientists who may identify more with women's health or sex & gender fields than with eye & vision fields. Nevertheless, because this special issue needs a home, the following 12 topical areas each have here their own dedicated review: age-related maculopathy, central nervous system function and cognition & perception, diabetic retinopathy, dry eye, glaucoma, inherited diseases, lens and cataract, neuro-ophthalmology, ocular blood flow, ocular inflammatory disorders, optical coherence tomography, and sex/gender eye care disparities. This overview article itself raises additional points expressly concerning: (1) the estrogen therapy timing hypothesis, and (2) breast cancer treatment with aromatase inhibitors. PMID:25329177

  14. Predicting the effects of exploitation on male-first sex-changing fish

    Microsoft Academic Search

    P. P. Molloy; N. B. Goodwin; I. M. Côté; M. J. G. Gage; J. D. Reynolds

    2007-01-01

    Sex change is widespread among tropical marine fishes, many of which are targeted by fisheries. Conservation concerns have been raised that sex-changing species may be particularly prone to overexploitation by size-selective fishing. In the case of male-first sex-changers, populations may become egg limited if large females are disproportionately killed. However, if males reduce the size at which they change sex

  15. Attraction of Female and Male Bactrocera papayae to Conspecific Males Fed with Methyl Eugenol and Attraction of Females to Male Sex Pheromone Components

    Microsoft Academic Search

    Alvin Kah-Wei Hee; Keng-Hong Tan

    1998-01-01

    The attraction of female and male Bactrocera papayae to conspecific males fed with methyl eugenol (ME) and female attraction to male synthetic sex pheromone, trans-coniferyl alcohol (CF), were evaluated in a wind tunnel. Earlier and greater attraction were exhibited by both females and males to ME-fed than to non-ME-fed males as dusk approaches. Males increased their precopulatory behavior (i.e., wing

  16. Exploring the Interpersonal Relationships in Street-Based Male Sex Work: Results from an Australian Qualitative Study

    Microsoft Academic Search

    David Leary; Victor Minichiello

    2007-01-01

    While the literature on male sex work has increased significantly over the past decade, few studies examine the influence of relational dynamics in the lives of those engaged in male sex work. This qualitative study, conducted with a sample of male street sex workers in Sydney, Australia, explores how relationships color their involvement with sex work. The findings reveal the

  17. Male sex work and HIV risk among young heroin users in Hanoi, Vietnam

    PubMed Central

    Clatts, Michael C.; Giang, Le M.; Goldsamt, Lloyd A.; Yi, Huso

    2009-01-01

    The present study describes complex drug and sexual risk in a group of male sex workers (n=79) who were recruited in the context of a larger study of young heroin users in Hanoi, Vietnam (n=1270). Male sex workers were significantly more likely than male non-sex workers to be migrants (P<0.001) and to have unstable housing (P<0.001), to have lifetime exposure to marijuana (P<0.001), 3,4 methylenedioxymethamphetamine (MDMA, ecstasy) (P<0.01), amphetamines (P<0.05), cocaine (P<0.01) and morphine (P<0.001). Male sex workers are more likely to currently use MDMA (P<0.05), amphetamines (P<0.001), morphine (P<0.05) and to ‘smoke’ as their most frequent mode of heroin administration (P<0.01). Male sex workers are more likely to have both male and female concurrent sex partners (P<0.001), to have a history of sexual victimisation (P<0.001), to have had more than three different sex partners in the past 30 days (P<0.001), and to have had partners who injected drugs before sex (P<0.001) or who used drugs during sex (P<0.01). In their last sexual encounter with a client partner, approximately one-third (31.1%) reported having had receptive anal sex. In nearly three-quarters of these exchanges (71.4%), no condom was used. Similarly, in their last sexual encounter with a client partner, 42.2% reported having had insertive anal sex and in nearly half (47.4%) of these encounters no condom was used. Consistent with recent data from elsewhere in the region, there is an urgent need for additional research on male sex work in South-east Asia in order to properly situate behavioural interventions for male sex workers in this region. PMID:18082070

  18. Alcohol and drug use in Australian male sex workers: Its relationship to the safety outcome of the sex encounter

    Microsoft Academic Search

    V. Minichiello; R. Mariño; M. A. Khan; J. Browne

    2003-01-01

    This paper describes the self-reporting patterns of alcohol and drug consumption among male sex workers (MSWs) in three Australian cities during commercial sex encounters, and examines to what extent alcohol and drugs are used and whether this is related to the safe\\/unsafe outcome of the commercial sex encounter. One hundred and eighty-six MSWs from Brisbane, Sydney and Melbourne completed a

  19. Prevalence and correlates of sexual risk among male and female sex workers in Tijuana, Mexico

    Microsoft Academic Search

    Yasmina Katsulis; Alesha Durfee

    2012-01-01

    We investigated prevalence and correlates of sexual risk behaviours among male and female sex workers in Tijuana, Mexico, the busiest border crossing area on the US – Mexico border, analysing survey data from a purposive, cross-sectional sample of male and female sex workers who worked in a range of indoor and outdoor settings. Logistic regression was used to determine factors

  20. Female and Male Sex Offenders: A Comparison of Recidivism Patterns and Risk Factors

    ERIC Educational Resources Information Center

    Freeman, Naomi J.; Sandler, Jeffrey C.

    2008-01-01

    Few studies have empirically validated the assertion that female and male sex offenders are vastly different. Therefore, utilizing a matched sample of 780 female and male sex offenders in New York State, the current study explored differences and similarities of recidivism patterns and risk factors for the two offender groups. Results suggested…

  1. Disruption of Gypsy Moth1Male Sex Pheromone Behavior by High Frequency Sound2

    E-print Network

    Disruption of Gypsy Moth1Male Sex Pheromone Behavior by High Frequency Sound2 T.C.BAKER AND R. T 48824 Reprinted from the ENVIRONMENTALENTOMOLOGY #12;Disruption of Gypsy Moth1 Male Sex Pheromone Lymantria dispar L. (gypsy moth), while flying upwind toward a pheromone source, respond to high frequency

  2. Male gametocyte fecundity and sex ratio of a malaria parasite, Plasmodium mexicanum

    E-print Network

    Schall, Joseph J.

    Male gametocyte fecundity and sex ratio of a malaria parasite, Plasmodium mexicanum A. T. NEAL Evolutionary theory predicts that the sex ratio of Plasmodium gametocytes will be determined by the number gametocyte fecundity for sex ratio theory as applied to malaria parasites, few data are available on gamete

  3. Effects of sex of judge and sex of victim on recommended punishment of a male murderer in a mock scenario.

    PubMed

    McKelvie, Stuart J

    2002-10-01

    Two samples of undergraduates (36 women, 7 men; 44 women, 45 men) read a mock transcript in which a murderer's victim was a man or a woman, after which they made prison sentence and death penalty judgments. Female judges gave longer sentences for the female victim than for the male victim, whereas male judges gave longer sentences for the male victim than for the female victim. This same-sex bias suggests that extralegal factors can affect judgments about sentencing. PMID:12416848

  4. From Client to Pimp: Male Violence against Female Sex Workers

    ERIC Educational Resources Information Center

    Karandikar, Sharvari; Prospero, Moises

    2010-01-01

    The present study explores intimate partner violence (IPV) among female sex workers from the red-light area based in Mumbai, India. Using a grounded theory approach, in-depth interviews were conducted with ten sex workers to explore their experiences of IPV in the context of commercial sex work. Narratives were analyzed and themes constructed. A…

  5. Sex-Biased Temporal Gene Expression in Male and Female Floral Buds of Seabuckthorn (Hippophae rhamnoides)

    PubMed Central

    Chawla, Aseem; Stobdan, Tsering; Srivastava, Ravi B.; Jaiswal, Varun; Chauhan, Rajinder S.; Kant, Anil

    2015-01-01

    Seabuckthorn is an economically important dioecious plant in which mechanism of sex determination is unknown. The study was conducted to identify seabuckthorn homologous genes involved in floral development which may have role in sex determination. Forty four putative Genes involved in sex determination (GISD) reported in model plants were shortlisted from literature survey, and twenty nine seabuckthorn homologous sequences were identified from available seabuckthorn genomic resources. Of these, 21 genes were found to differentially express in either male or female flower bud stages. HrCRY2 was significantly expressed in female flower buds only while HrCO had significant expression in male flowers only. Among the three male and female floral development stages (FDS), male stage II had significant expression of most of the GISD. Information on these sex-specific expressed genes will help in elucidating sex determination mechanism in seabuckthorn. PMID:25915052

  6. Sex-Biased Temporal Gene Expression in Male and Female Floral Buds of Seabuckthorn (Hippophae rhamnoides).

    PubMed

    Chawla, Aseem; Stobdan, Tsering; Srivastava, Ravi B; Jaiswal, Varun; Chauhan, Rajinder S; Kant, Anil

    2015-01-01

    Seabuckthorn is an economically important dioecious plant in which mechanism of sex determination is unknown. The study was conducted to identify seabuckthorn homologous genes involved in floral development which may have role in sex determination. Forty four putative Genes involved in sex determination (GISD) reported in model plants were shortlisted from literature survey, and twenty nine seabuckthorn homologous sequences were identified from available seabuckthorn genomic resources. Of these, 21 genes were found to differentially express in either male or female flower bud stages. HrCRY2 was significantly expressed in female flower buds only while HrCO had significant expression in male flowers only. Among the three male and female floral development stages (FDS), male stage II had significant expression of most of the GISD. Information on these sex-specific expressed genes will help in elucidating sex determination mechanism in seabuckthorn. PMID:25915052

  7. MMPI Profiles of Males with Abnormal Sex Chromosome Complements

    ERIC Educational Resources Information Center

    Rosen, M.; And Others

    1971-01-01

    Nine males with Klinefelter's syndrome (XXY) and seven XYY males, located primarily in prisons and psychiatric hospitals, were administered the Minnesota Multiphasic Personality Inventory. (Author/KW)

  8. Fluorochemicals used in food packaging inhibit male sex hormone synthesis

    SciTech Connect

    Rosenmai, A.K., E-mail: akjro@food.dtu.dk [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Nielsen, F.K. [Section of Toxicology, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2100 Copenhagen (Denmark)] [Section of Toxicology, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2100 Copenhagen (Denmark); Pedersen, M. [Division of Food Chemistry, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark)] [Division of Food Chemistry, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Hadrup, N. [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark)] [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Trier, X. [Division of Food Chemistry, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark)] [Division of Food Chemistry, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Christensen, J.H. [Department of Basic Sciences and Environment, Faculty of Life Sciences, University of Copenhagen, DK-1871 Frederiksberg C. (Denmark)] [Department of Basic Sciences and Environment, Faculty of Life Sciences, University of Copenhagen, DK-1871 Frederiksberg C. (Denmark); Vinggaard, A.M. [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark)] [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark)

    2013-01-01

    Polyfluoroalkyl phosphate surfactants (PAPS) are widely used in food contact materials (FCMs) of paper and board and have recently been detected in 57% of investigated materials. Human exposure occurs as PAPS have been measured in blood; however knowledge is lacking on the toxicology of PAPS. The aim of this study was to elucidate the effects of six fluorochemicals on sex hormone synthesis and androgen receptor (AR) activation in vitro. Four PAPS and two metabolites, perfluorooctanoic acid (PFOA) and 8:2 fluorotelomer alcohol (8:2 FTOH) were tested. Hormone profiles, including eight steroid hormones, generally showed that 8:2 diPAPS, 8:2 monoPAPS and 8:2 FTOH led to decreases in androgens (testosterone, dehydroepiandrosterone, and androstenedione) in the H295R steroidogenesis assay. Decreases were observed for progesterone and 17-OH-progesterone as well. These observations indicated that a step prior to progestagen and androgen synthesis had been affected. Gene expression analysis of StAR, Bzrp, CYP11A, CYP17, CYP21 and CYP19 mRNA showed a decrease in Bzrp mRNA levels for 8:2 monoPAPS and 8:2 FTOH indicating interference with cholesterol transport to the inner mitochondria. Cortisol, estrone and 17?-estradiol levels were in several cases increased with exposure. In accordance with these data CYP19 gene expression increased with 8:2 diPAPS, 8:2 monoPAPS and 8:2 FTOH exposures indicating that this is a contributing factor to the decreased androgen and the increased estrogen levels. Overall, these results demonstrate that fluorochemicals present in food packaging materials and their metabolites can affect steroidogenesis through decreased Bzrp and increased CYP19 gene expression leading to lower androgen and higher estrogen levels. -- Highlights: ? Fluorochemicals found in 57% of paper and board food packaging were tested. ? Collectively six fluorochemicals were tested for antiandrogenic potential in vitro. ? Three out of six tested fluorochemicals inhibited synthesis of male sex hormones. ? Generally, levels of estrogens and cortisol stayed unaffected or increased. ? The effect on steroid synthesis was specific on gene expression of Bzrp and CYP19.

  9. Female-biased sex ratios and the proportion of cryptic male morphs of migrant juvenile Ruffs

    E-print Network

    Female-biased sex ratios and the proportion of cryptic male morphs of migrant juvenile Ruffs, their proportion among juveniles provides the first estimate of the morphs'proportional reproductive suc- cess. 1 #12;ratios of male morphs, being unique among birds in having three genetically distinct male morphs

  10. Anim. Behav., 1998, 55, 16311635 Sex recognition and mate choice by male western toads, Bufo boreas

    E-print Network

    Blaustein, Andrew R.

    Anim. Behav., 1998, 55, 1631­1635 Sex recognition and mate choice by male western toads, Bufo and mate choice in male western toads, Bufo boreas. When given a simultaneous choice between a male & Cohen 1995). Frog and toad advertisement calls may be considered a form of long-range courtship (Rand

  11. “In different situations, in different ways”: Male sex work in St. Petersburg, Russia

    PubMed Central

    Niccolai, Linda M; King, Elizabeth J; Eritsyan, Ksenia; Safiullina, Liliya; Rusakova, Maia M

    2013-01-01

    We conducted a qualitative study of male sex work in St. Petersburg Russia with a focus on social vulnerabilities, HIV risk perception, and HIV-related behaviours. In-depth interviews were conducted with individuals knowledgeable about male sex work through their profession (n=8) and with male sex workers themselves (n=12). Male sex work involves a variety of exchanges including expensive vacations, negotiated monetary amounts, or simply access to food. Methods to find clients included the Internet, social venues (e.g. gay clubs and bars), and public places (e.g. parks). Use of the Internet greatly facilitated male sex work in a variety of ways. It was used by both individuals and agencies to find clients, and appeared to be increasing. Men often reported not being professionally connected to other male sex workers and limited disclosure about their work. Many were aware of the work-related risks to personal safety including violence and robbery by clients. Perceived risk for HIV was mostly abstract, and several exceptions to condom use with clients were noted. Alcohol use was reported as moderate but consumed frequently in association with work. These data suggest that the most salient risks for male sex workers include professional isolation, threats to personal safety, limited perceived HIV risk, and sub-optimal levels of condom use. PMID:23464743

  12. 'In different situations, in different ways': male sex work in St. Petersburg, Russia.

    PubMed

    Niccolai, Linda M; King, Elizabeth J; Eritsyan, Ksenia U; Safiullina, Liliya; Rusakova, Maia M

    2013-01-01

    We conducted a qualitative study of male sex work in St. Petersburg Russia with a focus on social vulnerabilities, HIV-risk perception and HIV-related behaviours. In-depth interviews were conducted with individuals knowledgeable about male sex work through their profession and with male sex workers themselves. Male sex work involves a variety of exchanges, including expensive vacations, negotiated monetary amounts or simply access to food. Methods of finding clients included the Internet, social venues (e.g. gay clubs and bars) and public places (e.g. parks). Use of the Internet greatly facilitated male sex work in a variety of ways. It was used by both individuals and agencies to find clients, and appeared to be increasing. Men often reported not being professionally connected to other male sex workers and limited disclosure about their work. Many were aware of the work-related risks to personal safety, including violence and robbery by clients. Perceived risk for HIV was mostly abstract and several exceptions to condom use with clients were noted. Alcohol use was reported as moderate but alcohol was consumed frequently in association with work. These data suggest that the most salient risks for male sex workers include professional isolation, threats to personal safety, limited perceived HIV risk and sub-optimal levels of condom use. PMID:23464743

  13. Perceived stigma of purchasing sex among Latino and non-Latino male clients of female sex workers in Tijuana, Mexico.

    PubMed

    Pitpitan, Eileen V; Strathdee, Steffanie A; Semple, Shirley J; Wagner, Karla D; Chavarin, Claudia V; Earnshaw, Valerie A; Patterson, Thomas L

    2015-02-01

    HIV prevention efforts must be comprehensive in their understanding of the factors involved in HIV risk. Male clients, who have received less research attention than female sex workers (FSWs), may experience stigma as a function of purchasing sex. Perceived stigma may be related to poor psychological outcomes, risky psychosexual characteristics, and higher drug and sexual risk behavior among male clients of FSWs. However, perceived stigma of purchasing sex may differ between clients of different ethnic groups. In the present study, we examine the correlates of perceived stigma of purchasing sex among Latino versus non-Latino male clients of FSWs in Tijuana, Mexico. Using time-location sampling, we recruited 375 male clients (323 Latino, 52 non-Latino) in Tijuana who completed a computerized survey on various measures. We measured perceived stigma of purchasing sex using three items we developed for this study. Using linear regression analyses we found that perceived stigma was associated with greater guilt, a greater feeling of escape from everyday life, and more negative condom attitudes among Latino clients. This was not found among non-Latino clients. Features of Latino culture, like machismo, and how they may relate to stigma of purchasing sex are discussed. PMID:23979714

  14. Shadow of domestic violence and extramarital sex cohesive with spousal communication among males in Nepal

    PubMed Central

    2014-01-01

    Background Public health and human right issues are challenging in low and middle income countries. The main objectives of this paper were to determine the prevalence and factors associated with domestic violence, extramarital sex, and spousal communication among male. Methods A cross-sectional study among 2466 married males in Kathmandu, Nepal was conducted using random sampling method. Adjusted odds ratios (AORs) and 95% confidence intervals (CI) of associated factors were estimated by stepwise backward likelihood ratio method. Results Prevalence of domestic violence was 63.14% (95% CI 61.20-65.05), extramarital sex was 32.12% (95% CI 30.27-34.00), and spousal communication was 48.87% (95% CI 46.85-50.90). Nearly one in five male (18.20%) had not used condom during extramarital sex. Interestingly, male who had more than three or equal children were less likely to have perpetrated domestic violence compared with those who had less children. Older male aged 25 and above were more likely (AORs?=?1.55, 95% CI 1.19-2.03) to have extramarital sex compared with male aged 24 or below. Those male who had studied secondary or higher level of education were less likely to have extramarital sex compared to those who had primary level or no education. Male who had higher income were more likely to have spousal communication compared to those who had less income. Surprisingly, those male who had extramarital sex were less likely to have spousal communication compared with those was not involved in extramarital sex. Conclusion Practice of domestic violence and extramarital sex is quite common among married male in Nepal, where spousal communication is sparse. These findings can be used to advocate for immediate attention and activities needs to be endorsed by policymakers and programmers. PMID:24924872

  15. Behavioral and psychosocial correlates of anal sex among male clients of female sex workers in Tijuana, Mexico.

    PubMed

    Semple, Shirley J; Strathdee, Steffanie A; Pitpitan, Eileen V; Chavarin, Claudia; Patterson, Thomas L

    2015-05-01

    Most studies of heterosexual sex risk practices have focused on condomless vaginal sex despite evidence that condomless anal sex has a significantly higher risk of HIV transmission. The present study focused on male clients' anal sex practices with female sex workers (FSWs) in Tijuana, Mexico, where an HIV epidemic is growing among high-risk groups. Logistic regression analyses were used to identify psychosocial and behavioral correlates of anal sex among male clients. Our sample of HIV-negative men (N = 400) was predominantly Latino (87.5 %), born in Mexico (78.8 %), never married (36.8 %) or in a regular or common-law marriage (31.5 %), and employed (62.8 %), with an average age and education of 37.8 and 9.2 years, respectively. Eighty-nine percent identified as heterosexual and 11 % as bisexual. By design, 50 % of the sample resided in Tijuana and the other 50 % in San Diego County. Nearly half (49 %) reported at least one incident of anal sex with a FSW in Tijuana in the past 4 months; of those participants, 85 % reported that one or more of their anal sex acts with FSWs had been without a condom. In a multivariate model, anal sex with a FSW in the past 4 months was associated with bisexual identification, methamphetamine use with FSWs, repeat visits to the same FSW, higher scores on perceived stigma about being a client of FSWs, and sexual compulsivity. Prevention programs are needed that address the behavioral and psychosocial correlates of heterosexual anal sex in order to reduce HIV/STI transmission risk among male clients, FSWs, and their sexual network members. PMID:25795530

  16. Motivating and Reinforcing Functions of the Male Sex Role: Social Analogues of Partial Reinforcement, Delay of Reinforcement, and Intermittent Shock.

    ERIC Educational Resources Information Center

    Cramer, Robert Ervin; And Others

    1989-01-01

    Reports on three experiments that do the following: 1) investigate the motivational and reinforcing structure underlying male sex role action in a three-person (a female and two males) exchange; and 2) contribute new information on females' interpersonal evaluation of males expressing masculine sex typed and androgynous sex role orientation. (MW)

  17. Comparing performance among male and female candidates in sex-specific clinical knowledge in the MRCGP

    PubMed Central

    Siriwardena, A Niroshan; Irish, Bill; Asghar, Zahid B; Dixon, Hilton; Milne, Paul; Neden, Catherine; Richardson, Jo; Blow, Carol

    2012-01-01

    Background Patients often seek doctors of the same sex, particularly for sex-specific complaints and also because of a perception that doctors have greater knowledge of complaints relating to their own sex. Few studies have investigated differences in knowledge by sex of candidate on sex-specific questions in medical examinations. Aim The aim was to compare the performance of males and females in sex-specific questions in a 200-item computer-based applied knowledge test for licensing UK GPs. Design and setting A cross-sectional design using routinely collected performance and demographic data from the first three versions of the Applied Knowledge Test, MRCGP, UK. Method Questions were classified as female specific, male specific, or sex neutral. The performance of males and females was analysed using multiple analysis of covariance after adjusting for sex-neutral score and demographic confounders. Results Data were included from 3627 candidates. After adjusting for sex-neutral score, age, time since qualification, year of speciality training, ethnicity, and country of primary medical qualification, there were differences in performance in sex-specific questions. Males performed worse than females on female-specific questions (–4.2%, 95% confidence interval [CI] = –5.7 to –2.6) but did not perform significantly better than females on male-specific questions (0.3%, 95% CI = –2.6 to 3.2%. Conclusion There was evidence of better performance by females in female-specific questions but this was small relative to the size of the test. Differential performance of males and females in sex-specific questions in a licensing examination may have implications for vocational and post-qualification general practice training. PMID:22687238

  18. Exploring the interpersonal relationships in street-based male sex work: results from an Australian qualitative study.

    PubMed

    Leary, David; Minichiello, Victor

    2007-01-01

    While the literature on male sex work has increased significantly over the past decade, few studies examine the influence of relational dynamics in the lives of those engaged in male sex work. This qualitative study, conducted with a sample of male street sex workers in Sydney, Australia, explores how relationships color their involvement with sex work. The findings reveal the complexity of their relationships and how their interactions with others shape their engagement in sex work. The data also offer insight into how exit pathways are influenced by money and relationships that occur within this particular male sex work setting. Implications for health policy and intervention are considered. PMID:18019070

  19. Male Sex Roles in Magazine Advertising, 1959-1979.

    ERIC Educational Resources Information Center

    Skelly, Gerald U.; Lundstrom, William J.

    1981-01-01

    Advertising featuring men appears to be moving gradually toward a decrease in sex-role stereotyping, although the progress is obviously slow. Of the 660 advertisements examined, only 13 were in the category showing men performing nonstereotypic roles capably or acknowledging that the sexes are fully equal. (PD)

  20. Sex ratio distortion in Acraea encedon (Lepidoptera: Nymphalidae) is caused by a male-killing bacterium

    Microsoft Academic Search

    Francis M Jiggins; Gregory D D Hurst; Michael E N Majerus

    1998-01-01

    Females of the butterfly Acraea encedon produce either entirely female offspring or males and females in an almost 1:1 sex ratio. The sex ratio produced is maternally inherited and was previously attributed to sex chromosome meiotic drive. We report that all-female lineages are associated with low egg-hatching rates and that the trait is cured by antibiotic treatment. We thus reject

  1. The Relationship of Trauma Exposure to Sex Offending Behavior among Male Juvenile Offenders.

    ERIC Educational Resources Information Center

    McMackin, Robert A.; Leisen, Mary Beth; Cusack, John R.; LaFratta, Joseph; Litwin, Peter

    2002-01-01

    Study identifies ways that traumatic experiences and trauma-associated feelings can be offense triggers for juvenile sex offenders. Researchers interviewed the treating clinicians of 40 male juvenile sex offenders. Overall, clinicians identified prior trauma exposure as being related to the offense triggers in 85% of offenders. Implications for…

  2. the DomeMales are lured byfood and sex into erotic contests and deadly brawls

    E-print Network

    Watson, Paul J.

    Dancing in the DomeMales are lured byfood and sex into erotic contests and deadly brawls by Paul J dome webs between low, leafless branches. Webs are usually four to six- teen inches wide space, where they annually' reenact a silent, ancient drama of sex and combat. My study site

  3. Using Lod Scores to Detect Sex Differences in Male-Female Recombination Fractions

    Microsoft Academic Search

    B. Feenstra; D. A. Greenberg; S. E. Hodge

    2004-01-01

    Human recombination fraction (RF) can differ between males and females, but investigators do not always know which disease genes are located in genomic areas of large RF sex differences. Knowledge of RF sex differences contributes to our understanding of basic biology and can increase the power of a linkage study, improve gene localization, and provide clues to possible imprinting. One

  4. Wolbachia, sex ratio bias and apparent male killing in the harlequin beetle riding pseudoscorpion

    Microsoft Academic Search

    D W Zeh; J A Zeh; M M Bonilla

    2005-01-01

    Bacterial endosymbionts that manipulate host reproduction are now known to be widespread in insects and other arthropods. Since they inhabit the cytoplasm and are maternally inherited, these microorganisms can enhance their fitness by biasing host sex ratio in favour of females. At its most extreme, sex ratio manipulation may be achieved by killing male embryos, as occurs in a number

  5. Hepatic injury induces contrasting response in liver and kidney to chemicals that are metabolically activated: Role of male sex hormone

    SciTech Connect

    Kim, Young C. [College of Pharmacy, Seoul National University, San 56-1 Shinrim-Dong, Kwanak-Ku, Seoul (Korea, Republic of)], E-mail: youckim@snu.ac.kr; Yim, Hye K.; Jung, Young S. [College of Pharmacy, Seoul National University, San 56-1 Shinrim-Dong, Kwanak-Ku, Seoul (Korea, Republic of); Park, Jae H. [College of Veterinary Medicine, Seoul National University, San 56-1 Shinrim-Dong, Kwanak-Ku, Seoul (Korea, Republic of); Kim, Sung Y. [College of Pharmacy, Wonkwang University, 344-2 Shinyong-Dong, Iksan (Korea, Republic of)

    2007-08-15

    Injury to liver, resulting in loss of its normal physiological/biochemical functions, may adversely affect a secondary organ. We examined the response of the liver and kidney to chemical substances that require metabolic activation for their toxicities in mice with a preceding liver injury. Carbon tetrachloride treatment 24 h prior to a challenging dose of carbon tetrachloride or acetaminophen decreased the resulting hepatotoxicity both in male and female mice as determined by histopathological examination and increases in serum enzyme activities. In contrast, the renal toxicity of the challenging toxicants was elevated markedly in male, but not in female mice. Partial hepatectomy also induced similar changes in the hepatotoxicity and nephrotoxicity of a challenging toxicant, suggesting that the contrasting response of male liver and kidney was associated with the reduction of the hepatic metabolizing capacity. Carbon tetrachloride pretreatment or partial hepatectomy decreased the hepatic xenobiotic-metabolizing enzyme activities in both sexes but elevated the renal p-nitrophenol hydroxylase, p-nitroanisole O-demethylase and aminopyrine N-demethylase activities significantly only in male mice. Increases in Cyp2e1 and Cyp2b expression were also evident in male kidney. Castration of males or testosterone administration to females diminished the sex-related differences in the renal response to an acute liver injury. The results indicate that reduction of the hepatic metabolizing capacity induced by liver injury may render secondary target organs susceptible to chemical substances activated in these organs. This effect may be sex-specific. It is also suggested that an integrated approach should be taken for proper assessment of chemical hazards.

  6. The sicker sex: understanding male biases in parasitic infection, resource allocation and fitness.

    PubMed

    Córdoba-Aguilar, Alex; Munguía-Steyer, Roberto

    2013-01-01

    The "sicker sex" idea summarizes our knowledge of sex biases in parasite burden and immune ability whereby males fare worse than females. The theoretical basis of this is that because males invest more on mating effort than females, the former pay the costs by having a weaker immune system and thus being more susceptible to parasites. Females, conversely, have a greater parental investment. Here we tested the following: a) whether both sexes differ in their ability to defend against parasites using a natural host-parasite system; b) the differences in resource allocation conflict between mating effort and parental investment traits between sexes; and, c) effect of parasitism on survival for both sexes. We used a number of insect damselfly species as study subjects. For (a), we quantified gregarine and mite parasites, and experimentally manipulated gregarine levels in both sexes during adult ontogeny. For (b), first, we manipulated food during adult ontogeny and recorded thoracic fat gain (a proxy of mating effort) and abdominal weight (a proxy of parental investment) in both sexes. Secondly for (b), we manipulated food and gregarine levels in both sexes when adults were about to become sexually mature, and recorded gregarine number. For (c), we infected male and female adults of different ages and measured their survival. Males consistently showed more parasites than females apparently due to an increased resource allocation to fat production in males. Conversely, females invested more on abdominal weight. These differences were independent of how much food/infecting parasites were provided. The cost of this was that males had more parasites and reduced survival than females. Our results provide a resource allocation mechanism for understanding sexual differences in parasite defense as well as survival consequences for each sex. PMID:24194830

  7. Tribolium castaneum Transformer-2 regulates sex determination and development in both males and females

    PubMed Central

    Shukla, Jayendra Nath; Palli, Subba Reddy

    2014-01-01

    Tribolium castaneum Transformer (TcTra) is essential for female sex determination and maintenance through the regulation of sex-specific splicing of doublesex (dsx) pre-mRNA. In females, TcTra also regulates the sex-specific splicing of its own pre-mRNA to ensure continuous production of functional Tra protein. Transformer protein is absent in males and hence dsx pre-mRNA is spliced in a default mode. The mechanisms by which males inhibit the production of functional Tra protein are not known. Here, we report on functional characterization of transformer-2 (tra-2) gene (an ortholog of Drosophila transformer-2) in T. castaneum. RNA interference-mediated knockdown in the expression of gene coding for tra-2 in female pupae or adults resulted in the production of male-specific isoform of dsx and both female and male isoforms of tra suggesting that Tra-2 is essential for the female-specific splicing of tra and dsx pre-mRNAs. Interestingly, knockdown of tra-2 in males did not affect the splicing of dsx but resulted in the production of both female and male isoforms of tra suggesting that Tra-2 suppresses female-specific splicing of tra pre-mRNA in males. This dual regulation of sex-specific splicing of tra pre-mRNA ensures a tight regulation of sex determination and maintenance. These data suggest a critical role for Tra-2 in suppression of female sex determination cascade in males. In addition, RNAi studies showed that Tra-2 is also required for successful embryonic and larval development in both sexes. PMID:24056158

  8. Sex organ determination and differentiation in the dioecious plant Melandrium album ( Silene latifolia ): a cytological and histological analysis

    Microsoft Academic Search

    Isabelle Farbos; Margarida Oliveira; Ioan Negrutiu; A. Mouras

    1997-01-01

    Melandrium album (Silene alba) is a dioecious plant with heteromorphic sex chromosomes (XY system). Sexual dimorphism is a result of developmental blocks\\u000a in male or female reproductive organ formation within young bipotential flower buds. Progress in understanding the genetic\\u000a and molecular mechanisms controlling sex determination in this species relies on a detailed description of developmental timing\\u000a in the two sexes,

  9. Differential Response of Males and Females to Work Situations Which Evoke Sex Role Stereotypes.

    ERIC Educational Resources Information Center

    Gutek, Barbara A.; Stevens, Denise A.

    The hypothesis in the present study is that in work situations which evoke sex role stereotypes, women will respond less stereotypically than males since it is in their best interest to do so. The method comes from the Rosen et al. (1975) study of male managers. In the present study, 293 introductory psychology students were asked to role play an…

  10. SEX HORMONES DURING ALCOHOL WITHDRAWAL: A LONGITUDINAL STUDY OF 29 MALE ALCOHOLICS DURING DETOXIFICATION

    Microsoft Academic Search

    JAAN RUUSA; BO BERGMAN; MONA-LISA SUNDELL

    It is a well-known fact that alcohol affects sex hormone levels in males. Even in the absence of liver dysfunction, there is still a direct toxic effect of ethanol on testosterone synthesis resulting in acutely decreased values. This study is based on 29 male alcoholics without severe signs of liver disease treated on the alcohol detoxification ward at Huddinge hospital

  11. Male adolescent birth control behavior: The importance of developmental factors and sex differences

    Microsoft Academic Search

    Donald D. Cohen; Ryda D. Rose

    1984-01-01

    A survey of sex and birth control behavior of 51 male adolescents aged 15–17 was conducted utilizing a structured interview protocol. The purpose of the study was to describe male adolescent birth control behavior incorporating developmental issues, and to interpret the findings in light of what is known about female birth control behavior. Based on research with teenage females, three

  12. The Tyranny of Surveillance: Male Teachers and the Policing of Masculinities in a Single Sex School

    ERIC Educational Resources Information Center

    Martino, Wayne; Frank, Blye

    2006-01-01

    This paper draws on research into male teachers in one single sex high school in the Australian context to highlight how issues of masculinity impact on their pedagogical practices and relationships with boys. The study is situated within the broader international field of research on male teachers, masculinities and schooling in Australia, the UK…

  13. Sex workers' noncommercial male partners who inject drugs report higher-risk sexual behaviors.

    PubMed

    Robertson, Angela M; Syvertsen, Jennifer L; Palinkas, Lawrence A; Vera, Alicia; Rangel, Gudelia; Martinez, Gustavo; Strathdee, Steffanie A

    2013-10-01

    Female sex workers are less likely to use condoms with noncommercial male partners than clients. We compare noncommercial male partners who do and do not inject drugs in Tijuana and Ciudad Juárez, Mexico. Sexual risk behaviors were more prevalent among injectors, who could promote HIV/sexually transmitted infection transmission in this region. PMID:24275732

  14. Quantity matters: male sex pheromone signals mate quality in the parasitic wasp Nasonia vitripennis

    PubMed Central

    Ruther, Joachim; Matschke, Michael; Garbe, Leif-Alexander; Steiner, Sven

    2009-01-01

    Sexual selection theory asserts that females are well adapted to sense signals indicating the quality of potential mates. One crucial male quality parameter is functional fertility (i.e. the success of ejaculates in fertilizing eggs). The phenotype-linked fertility hypothesis (PLFH) predicts that functional fertility of males is reflected by phenotypic traits that influence female mate choice. Here, we show for Nasonia vitripennis, a parasitic wasp with haplodiploid sex determination and female-biased sex ratios, that females use olfactory cues to discriminate against sperm-limited males. We found sperm limitation in newly emerged and multiply mated males (seven or more previous matings) as indicated by a higher proportion of sons in the offspring fathered by these males. Sperm limitation correlated with clearly reduced pheromone titres. In behavioural bioassays, females oriented towards higher doses of the synthetic pheromone and were attracted more often to scent marks of males with a full sperm load than to those of sperm-limited males. Our data support the PLFH and suggest that N. vitripennis females are able to decrease the risk of getting constrained to produce suboptimal offspring sex ratios by orienting towards gradients of the male sex pheromone. PMID:19535374

  15. The tyranny of surveillance: male teachers and the policing of masculinities in a single sex school

    Microsoft Academic Search

    Wayne Martino; Blye Frank

    2006-01-01

    This paper draws on research into male teachers in one single sex high school in the Australian context to highlight how issues of masculinity impact on their pedagogical practices and relationships with boys. The study is situated within the broader international field of research on male teachers, masculinities and schooling in Australia, the UK and the US and provides further

  16. SEX-RATIO EVOLUTION IN SEX CHANGING ANIMALS

    Microsoft Academic Search

    David J. Allsop; Stuart A. West

    2004-01-01

    Sex allocation theory is often able to make clear predictions about when individuals should facultatively adjust their offspring sex ratio (proportion male) in response to local conditions, but not the consequences for the overall population sex ratio. A notable exception to this is in sex changing organisms, where theory predicts that: (1) organisms should have a sex ratio biased toward

  17. Persistent organic pollutants and male reproductive health

    PubMed Central

    Vested, Anne; Giwercman, Aleksander; Bonde, Jens Peter; Toft, Gunnar

    2014-01-01

    Environmental contaminants such as persistent organic pollutants (POPs) are man-made bioaccumulative compounds with long half-lives that are found throughout the world as a result of heavy use in a variety of consumer products during the twentieth century. Wildlife and animal studies have long suggested adverse effects of exposure to these compounds on human reproductive health, which, according to the endocrine disrupter hypothesis, are ascribed to the compounds’ potential to interfere with endocrine signaling, especially when exposure occurs during certain phases of fetal and childhood development. An extensive number of epidemiological studies have addressed the possible effects of exposure to POPs on male reproductive health, but the results are conflicting. Thus far, most studies have focused on investigating exposure and the different reproductive health outcomes during adulthood. Some studies have addressed the potential harmful effects of fetal exposure with respect to malformations at birth and/or reproductive development, whereas only a few studies have been able to evaluate whether intrauterine exposure to POPs has long-term consequences for male reproductive health with measurable effects on semen quality markers and reproductive hormone levels in adulthood. Humans are not exposed to a single compound at a time, but rather, to a variety of different substances with potential divergent hormonal effects. Hence, how to best analyze epidemiological data on combined exposures remains a significant challenge. This review on POPs will focus on current knowledge regarding the potential effects of exposure to POPs during fetal and childhood life and during adulthood on male reproductive health, including a critical revision of the endocrine disruption hypothesis, a comment on pubertal development as part of reproductive development and a comment on how to account for combined exposures in epidemiological research. PMID:24369135

  18. Mental Health and Sexual Identity in a Sample of Male Sex Workers in the Czech Republic

    PubMed Central

    Bar-Johnson, Michael; Weiss, Petr

    2014-01-01

    Background Previous qualitative research has examined male sex workers in the Czech Republic, but this mapping study is the first to investigate male sex work in a quantitative research design and focus on the mental health of these sex workers. This study also examines male sex workers’ mental health problems in relation to their sexual identity or orientation. Material/Methods A sample of Czech male sex workers (N=40) were examined on a range of sexual and psychological variables using a quantitative survey administered face-to-face. The study employed locally validated versions of Beck’s Depression Inventory and Zung’s Self-Report Anxiety Scale. Results The results indicate that for homosexuals, working as a male sex worker is not related to any serious mental health problems. However, those identifying as heterosexual and bisexual more frequently reported symptoms of depression and bisexuals showed significantly more anxiety. Conclusions These findings suggest sexual identity is an important issue to consider when addressing the mental health needs of this population. PMID:25239091

  19. A qualitative study on commercial sex behaviors among male clients in Sichuan Province, China

    PubMed Central

    Yang, Cui; Latkin, Carl A.; Liu, Peng; Nelson, Kenrad E.; Wang, Cunlin; Luan, Rongsheng

    2015-01-01

    Males who seek commercial sex have been identified as an important “bridging population” in the transmission of HIV. There is little information on the HIV-related risk perceptions and behaviors among commercial sex male clients (CSMCs) in China. This study reports qualitative findings from six focus groups and 41 in-depth interviews with CSMCs in Sichuan Province, China. Commercial sex visits were described as a group activity and associated with patterns of social-network specific interactions and norms. Primary motivations for visiting female sex workers included peer pressure, stress reduction, and fulfilling a need for an intimate and emotional support. Male clients’ decisions about condom use were influenced by their perceived norms of condom use, susceptibility of HIV infection, and the condom policy and availability in the establishments. Implications of these findings for further research and interventions are discussed. PMID:20390503

  20. Male and Female Suicide Bombers: Different Sexes, Different Reasons?

    Microsoft Academic Search

    Karen Jacques; Paul J. Taylor

    2008-01-01

    This article analyzes the motivations and recruitment of female suicide terrorists. Biographical accounts of 30 female and 30 male suicide terrorists were coded for method of recruitment, motivation for attack, and outcome of attack. A log-linear analysis found that female suicide terrorists were motivated more by Personal events, whereas males were motivated more by Religious\\/nationalistic factors. Females were equally likely

  1. Male facial attractiveness and masculinity may provide sex- and culture-independent cues to semen quality.

    PubMed

    Soler, C; Kekäläinen, J; Núñez, M; Sancho, M; Álvarez, J G; Núñez, J; Yaber, I; Gutiérrez, R

    2014-09-01

    Phenotype-linked fertility hypothesis (PLFH) predicts that male secondary sexual traits reveal honest information about male fertilization ability. However, PLFH has rarely been studied in humans. The aim of the present study was to test PLFH in humans and to investigate whether potential ability to select fertile partners is independent of sex or cultural background. We found that on the contrary to the hypothesis, facial masculinity was negatively associated with semen quality. As increased levels of testosterone have been demonstrated to impair sperm production, this finding may indicate a trade-off between investments in secondary sexual signalling (i.e. facial masculinity) and fertility or status-dependent differences in investments in semen quality. In both sexes and nationalities (Spanish and Colombian), ranked male facial attractiveness predicted male semen quality. However, Spanish males and females estimated facial images generally more attractive (gave higher ranks) than Colombian raters, and in both nationalities, males gave higher ranks than females. This suggests that male facial cues may provide culture- and sex-independent information about male fertility. However, our results also indicate that humans may be more sensitive to facial attractiveness cues within their own populations and also that males may generally overestimate the attractiveness of other men to females. PMID:25056484

  2. The roles of Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes in sex determination and differentiation mechanisms: Ubiquity and diversity across the animal kingdom.

    PubMed

    Picard, Marion Anne-Lise; Cosseau, Céline; Mouahid, Gabriel; Duval, David; Grunau, Christoph; Toulza, Ève; Allienne, Jean-François; Boissier, Jérôme

    2015-07-01

    The Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes have been intensively studied because they represent major transcription factors in the pathways governing sex determination and differentiation. These genes have been identified in animal groups ranging from cnidarians to mammals, and some of the genes functionally studied. Here, we propose to analyze (i) the presence/absence of various Dmrt gene groups in the different taxa across the animal kingdom; (ii) the relative expression levels of the Dmrt genes in each sex; (iii) the specific spatial (by organ) and temporal (by developmental stage) variations in gene expression. This review considers non-mammalian animals at all levels of study (i.e. no particular importance is given to animal models), and using all types of sexual strategy (hermaphroditic or gonochoric) and means of sex determination (i.e. genetic or environmental). To conclude this global comparison, we offer an analysis of the DM domains conserved among the different DMRT proteins, and propose a general sex-specific pattern for each member of the Dmrt gene family. PMID:26043799

  3. Motivational Counseling: Implications for Counseling Male Juvenile Sex Offenders

    ERIC Educational Resources Information Center

    Patel, Samir H.; Lambie, Glenn W.; Glover, Michelle Muenzenmeyer

    2008-01-01

    Juvenile sex offenders (JSOs) often appear unmotivated to change, which thus necessitates a therapeutic approach that matches "resistant" client characteristics. In this article, the authors review common traits of JSOs, introduce motivational counseling as an effective treatment modality, and offer a case illustration. (Contains 1 table and 1…

  4. Alcohol Use Among Female Sex Workers and Male Clients: An Integrative Review of Global Literature

    PubMed Central

    Li, Qing; Li, Xiaoming; Stanton, Bonita

    2010-01-01

    Aims: To review the patterns, contexts and impacts of alcohol use associated with commercial sex reported in the global literature. Methods: We identified peer-reviewed English-language articles from 1980 to 2008 reporting alcohol consumption among female sex workers (FSWs) or male clients. We retrieved 70 articles describing 76 studies, in which 64 were quantitative (52 for FSWs, 12 for male clients) and 12 qualitative. Results: Studies increased over the past three decades, with geographic concentration of the research in Asia and North America. Alcohol use was prevalent among FSWs and clients. Integrating quantitative and qualitative studies, multilevel contexts of alcohol use in the sex work environment were identified, including workplace and occupation-related use, the use of alcohol to facilitate the transition into and practice of commercial sex among both FSWs and male clients, and self-medication among FSWs. Alcohol use was associated with adverse physical health, illicit drug use, mental health problems, and victimization of sexual violence, although its associations with HIV/sexually transmitted infections and unprotected sex among FSWs were inconclusive. Conclusions: Alcohol use in the context of commercial sex is prevalent, harmful among FSWs and male clients, but under-researched. Research in this area in more diverse settings and with standardized measures is required. The review underscores the importance of integrated intervention for alcohol use and related problems in multilevel contexts and with multiple components in order to effectively reduce alcohol use and its harmful effects among FSWs and their clients. PMID:20089544

  5. Timing of male sex pheromone biosynthesis in a butterfly - different dynamics under direct or diapause development.

    PubMed

    Larsdotter-Mellström, Helena; Murtazina, Rushana; Borg-Karlson, Anna-Karin; Wiklund, Christer

    2012-05-01

    The life history traits and behavior of the butterfly Pieris napi are well-known, as the species is often used as a model organism for evolutionary and ecological studies. The species has two or more generations per year in the major part of its temperate distribution, and as different selection pressures affect the different generations, both behavioral and physiological seasonal polyphenisms have been shown previously. Here, we explored the dynamics of male sex pheromone production. The two generations are shown to have significantly different scent compositions early in life; the direct developers--who have shorter time for pupal development--need the first 24 hr of adult life after eclosion to synthesize the sex pheromone citral (geranial and neral 1:1)--whereas the diapausing individuals who have spent several months in the pupal stage eclose with adult scent composition. Resource allocation and biosynthesis also were studied in greater detail by feeding butterflies (13)C labeled glucose either in the larval or adult stage, and recording incorporation into geranial, neral, and other volatiles produced. Results demonstrate that the pheromone synthesized by newly eclosed adult males is based on materials ingested in the larval stage, and that adult butterflies are able to synthesize the pheromone components geranial and neral and the related alcohols also from adult intake of glucose. In summary, our study shows that time-stress changes the timing in biosynthesis of the complete pheromone between generations, and underpins the importance of understanding resource allocation and the physiological basis of life history traits. PMID:22555771

  6. Aging affects sex categorization of male and female faces in opposite ways.

    PubMed

    Kloth, Nadine; Damm, Madeleine; Schweinberger, Stefan R; Wiese, Holger

    2015-06-01

    Faces are rich in social information; they easily give away a person's sex, approximate age, feelings, or focus of attention. Past research has mostly focused on investigating the distinct facial signals and perceptual mechanisms that allow us to categorize faces on these individual dimensions. It is less well understood how the different kinds of facial information interact. Here we investigated how the age of a face affects the ease with which young and older adults categorize its sex. Disconfirming everyday intuition, we showed that sex categorization is not generally hampered for older faces. Although categorization of female faces took progressively more time with increasing age, the opposite was found for male faces (Experiment 1). Differential effects of stimulus blurring and inversion for male and female faces of different ages (Experiment 2) strongly suggest one feature as a crucial mediator of the interdependence of age and sex perception - skin texture. PMID:25974392

  7. Function and evolution of sterile sex organs in cryptically dioecious Petasites tricholobus (Asteraceae)

    PubMed Central

    Yu, Qian; Li, Deng-Xiu; Luo, Wei; Guo, You-Hao

    2011-01-01

    Background and Aims Why are sterile anthers and carpels retained in some flowering plants, given their likely costs? To address this question, a cryptically dioecious species, Petasites tricholobus, in which male and female plants each have two floret types that appear pistillate and hermaphroditic, was studied. The aim was to understand the function of sterile hermaphroditic florets in females. In addition, the first examination of functions of sterile female structures in male plants was conducted in the hermaphroditic florets on males of this species. These female structures are exceptionally large in this species despite being sterile. Methods Differences in floret morphology between the sex morphs were documented and the possible functions of sterile sex organs investigated using manipulative experiments. Tests were carried out to find out if sterile female structures in male florets attract pollinators and if they aid in pollen dispersal, also to find out if the presence and quantity of sterile hermaphroditic florets in females increase pollinator attraction and reproductive success. To investigate what floret types provide nectar, all types of florets were examined under a scanning electron microscope to search for nectaries. Key Results The sterile female structures in male florets did not increase pollinator visits but were essential to secondary pollen presentation, which significantly enhanced pollen dispersal. Sterile pistillate florets on male plants did not contribute to floral display and disappeared in nearly half of the male plants. The sterile hermaphroditic florets on female plants attracted pollinators by producing nectar and enhanced seed production. Conclusions The presence of female structures in male florets and hermaphroditic florets on female plants is adaptive despite being sterile, and may be evolutionarily stable. However, the pistillate florets on male plants appear non-adaptive and are presumably in decline. Differential fates of the sterile sex organs in the species are determined by both the historical constraints and the ecological functions. PMID:21546429

  8. Factors distinguishing homosexual males practicing risky and safer sex

    Microsoft Academic Search

    Karolynn Siegel; Frances Palamara Mesagno; Jin-Yi Chen; Grace Christ

    1989-01-01

    A longitudinal study of patterns of sexual behavior among asymptomatic, homosexual males in New York City was conducted. Participants were interviewed at two time points, 6 months apart. Based on their reports of sexual behavior during a recent 'typical' month, respondents were classified at each time point as engaging in safer (or low-risk) sexual practices versus high-risk sexual behaviors. Discriminant

  9. Sex-specific, male-line transgenerational responses in humans

    Microsoft Academic Search

    Marcus E Pembrey; Lars Olov Bygren; Gunnar Kaati; Sören Edvinsson; Kate Northstone; Michael Sjöström; Jean Golding

    2006-01-01

    Transgenerational effects of maternal nutrition or other environmental ‘exposures’ are well recognised, but the possibility of exposure in the male influencing development and health in the next generation(s) is rarely considered. However, historical associations of longevity with paternal ancestors' food supply in the slow growth period (SGP) in mid childhood have been reported. Using the Avon Longitudinal Study of Parents

  10. Family Size, Birth Order, and Parental Age Among Male Paraphilics and Sex Offenders

    Microsoft Academic Search

    Ron Langevin; Mara Langevin; Suzanne Curnoe

    2007-01-01

    A sample of 1823 male paraphilics, sex offenders, and non-sex offender controls were compared on family size, birth order,\\u000a and parents’ ages at the time of the probands’ births. Sample data were also compared to population data from Statistics Canada.\\u000a The men in all groups were from larger than average Canadian families and they tended to be later born. Paraphilics

  11. Sex determination in beetles: Production of all male progeny by Parental RNAi knockdown of transformer

    PubMed Central

    Shukla, Jayendra Nath; Palli, Subba Reddy

    2012-01-01

    Sex in insects is determined by a cascade of regulators ultimately controlling sex-specific splicing of a transcription factor, Doublesex (Dsx). We recently identified homolog of dsx in the red flour beetle, Tribolium castaneum (Tcdsx). Here, we report on the identification and characterization of a regulator of Tcdsx splicing in T. castaneum. Two male-specific and one female-specific isoforms of T. castaneum transformer (Tctra) were identified. RNA interference-aided knockdown of Tctra in pupa or adults caused a change in sex from females to males by diverting the splicing of Tcdsx pre-mRNA to male-specific isoform. All the pupa and adults developed from Tctra dsRNA injected final instar larvae showed male-specific sexually dimorphic structures. Tctra parental RNAi caused an elimination of females from the progeny resulting in production of all male progeny. Transformer parental RNAi could be used to produce all male population for use in pest control though sterile male release methods. PMID:22924109

  12. Absorption in imaginings, sex-role orientation, and the recall of dreams by males and females.

    PubMed

    Spanos, N P; Stam, H J; Radtke, H L; Nightingale, M E

    1980-06-01

    Questionnaire measures of dream recall frequency, number of sensory qualities in dreams and emotion in dreams were correlated with several imaginal ability and personality variables in male and female college students. Absorption (i.e., subjects' degree of involvement in such activities as daydreaming, watching a movie, etc.) was the most important predictor of dream variables in females. In males sex-role orientation contrary to stereotype (i.e., femininity) was the only variable significantly related to a dream variable (i.e., frequency of dream recall). The implications of these sex differences for research on dream recall are discussed. PMID:16366937

  13. Being male or living with a female: fear for partners by sex and sexual orientation.

    PubMed

    Drakulich, Kevin M; Rose, Kristin

    2013-06-01

    While substantial research attention has been paid to the disproportionately high levels of fear of crime among women relative to men, less attention has been paid to the apparent mirror of this: that men have disproportionately more concern for female partners than women do for male partners. The work that does exist on fear for partners has focused exclusively on different-sex partnerships. The present article proposes and explores several explanations for sex differences in fear for partners among different-sex as well as same-sex partnerships. The analysis uses a sample of persons who live with a partner (155 in same-sex and 2,817 in different-sex partnerships) from a Seattle survey that includes measures of altruistic fear, as well as measures of personal, familial, sexual assault, and sexual identity bias victimizations. Results suggest that female partners inspire more fear regardless of the sex of the respondents, that sex differences persist even after perceptions of danger are accounted for, and that personal fears and fears for children are positively associated with fears for partners and do not explain sex differences in such fears. These results are more consistent with explanations rooted in gendered perceptions of vulnerability and the shadow of sexual assault than explanations rooted in the differential gender socialization of men as protectors or of a limited capacity for fear. PMID:23277470

  14. Sex Reassignment Surgery in the Female-to-Male Transsexual.

    PubMed

    Monstrey, Stan J; Ceulemans, Peter; Hoebeke, Piet

    2011-08-01

    In female-to-male transsexuals, the operative procedures are usually performed in different stages: first the subcutaneous mastectomy which is often combined with a hysterectomy-ovarectomy (endoscopically assisted). The next operative procedure consists of the genital transformation and includes a vaginectomy, a reconstruction of the horizontal part of the urethra, a scrotoplasty and a penile reconstruction usually with a radial forearm flap (or an alternative). After about one year, penile (erection) prosthesis and testicular prostheses can be implanted when sensation has returned to the tip of the penis. The authors provide a state-of-the-art overview of the different gender reassignment surgery procedures that can be performed in a female-to-male transsexual. PMID:22851915

  15. Sex Reassignment Surgery in the Female-to-Male Transsexual

    PubMed Central

    Monstrey, Stan J.; Ceulemans, Peter; Hoebeke, Piet

    2011-01-01

    In female-to-male transsexuals, the operative procedures are usually performed in different stages: first the subcutaneous mastectomy which is often combined with a hysterectomy-ovarectomy (endoscopically assisted). The next operative procedure consists of the genital transformation and includes a vaginectomy, a reconstruction of the horizontal part of the urethra, a scrotoplasty and a penile reconstruction usually with a radial forearm flap (or an alternative). After about one year, penile (erection) prosthesis and testicular prostheses can be implanted when sensation has returned to the tip of the penis. The authors provide a state-of-the-art overview of the different gender reassignment surgery procedures that can be performed in a female-to-male transsexual. PMID:22851915

  16. Anal sex practices in heterosexual and male homosexual populations: a review of population-based data.

    PubMed

    Heywood, Wendy; Smith, Anthony M A

    2012-12-01

    Anal sex is known to be an important risk factor for anal cancer. Yet compared with vaginal intercourse, little is known about anal sex practices in either heterosexual or male homosexual populations. Of the data that are available, it appears a significant and increasing minority of heterosexuals have ever practised anal intercourse. Among homosexual men, most, but not all, report anal sex, with large proportions of men engaging in both insertive and receptive anal intercourse. The most significant finding of the review was the dearth of population-based data, particularly relating to homosexual men. PMID:22951046

  17. Organizing Effects of Sex Steroids on Brain Aromatase Activity in Quail

    PubMed Central

    Cornil, Charlotte A.; Ball, Gregory F.; Balthazart, Jacques; Charlier, Thierry D.

    2011-01-01

    Preoptic/hypothalamic aromatase activity (AA) is sexually differentiated in birds and mammals but the mechanisms controlling this sex difference remain unclear. We determined here (1) brain sites where AA is sexually differentiated and (2) whether this sex difference results from organizing effects of estrogens during ontogeny or activating effects of testosterone in adulthood. In the first experiment we measured AA in brain regions micropunched in adult male and female Japanese quail utilizing the novel strategy of basing the microdissections on the distribution of aromatase-immunoreactive cells. The largest sex difference was found in the medial bed nucleus of the stria terminalis (mBST) followed by the medial preoptic nucleus (POM) and the tuberal hypothalamic region. A second experiment tested the effect of embryonic treatments known to sex-reverse male copulatory behavior (i.e., estradiol benzoate [EB] or the aromatase inhibitor, Vorozole) on brain AA in gonadectomized adult males and females chronically treated as adults with testosterone. Embryonic EB demasculinized male copulatory behavior, while vorozole blocked demasculinization of behavior in females as previously demonstrated in birds. Interestingly, these treatments did not affect a measure of appetitive sexual behavior. In parallel, embryonic vorozole increased, while EB decreased AA in pooled POM and mBST, but the same effect was observed in both sexes. Together, these data indicate that the early action of estrogens demasculinizes AA. However, this organizational action of estrogens on AA does not explain the behavioral sex difference in copulatory behavior since AA is similar in testosterone-treated males and females that were or were not exposed to embryonic treatments with estrogens. PMID:21559434

  18. STI prevention and the male sex industry in London: evaluating a pilot peer education programme

    Microsoft Academic Search

    A Ziersch; J Gaffney; D R Tomlinson

    2000-01-01

    Objective: To evaluate the effectiveness of a pilot peer education STI prevention programme with male sex workers.Design: A process and outcome evaluation of the pilot programme undertaken in three London male escort agencies, using a quasi-experimental design.Subjects: Workers in three London escort agencies, including 88 who completed a questionnaire, five peer educators, and a further 16 men (including management) working

  19. Bisexual feelings and opposite-sex behavior in male Malaysian medical students.

    PubMed

    Buhrich, N; Armstrong, M S; McConaghy, N

    1982-10-01

    The sexual identity of 65 Malaysian male medical students was investigated by anonymous questionnaire. Of these students, 40% were aware of homosexual feelings prior to age 15 years, and 16% were so aware currently. There were correlations between current homosexual feelings and feminine sex dimorphic behavior during childhood and between current homosexual feelings and feminine gender identity. The results are discussed in light of results of a similar questionnaire completed by 138 male medical students in Sydney, Australia. PMID:7181646

  20. Operational sex ratio, mediated by synchrony of female arrival, alters the variance of male mating success in Japanese medaka

    Microsoft Academic Search

    JAMES W. A. GRANT; MICHAEL J. BRYANT; CATHERINE E. SOOS

    1995-01-01

    The hypotheses that variation in male mating success and use of aggression by competing males increase with decreasing synchrony of female arrival were experimentally tested. Groups of three male Japanese medaka,Oryzias latipes(Pisces, Oryziidae) were allowed to compete for females that were placed in the tank either simultaneously (synchronous treatment, male-to-female operational sex ratio=0·5) or sequentially (asynchronous treatment, operational sex ratio=3).

  1. Aggressive behavior of the male parent predicts brood sex ratio in a songbird.

    PubMed

    Szász, Eszter; Garamszegi, László Zsolt; Hegyi, Gergely; Szöll?si, Eszter; Markó, Gábor; Török, János; Rosivall, Balázs

    2014-08-01

    Brood sex ratio is often affected by parental or environmental quality, presumably in an adaptive manner that is the sex that confers higher fitness benefits to the mother is overproduced. So far, studies on the role of parental quality have focused on parental morphology and attractiveness. However, another aspect, the partner's behavioral characteristics, may also be expected to play a role in brood sex ratio adjustment. To test this hypothesis, we investigated whether the proportion of sons in the brood is predicted by the level of territorial aggression displayed by the father, in the collared flycatcher (Ficedula albicollis). The proportion of sons in the brood was higher in early broods and increased with paternal tarsus length. When controlling for breeding date and body size, we found a higher proportion of sons in the brood of less aggressive fathers. Male nestlings are more sensitive to the rearing environment, and the behavior of courting males may often be used by females to assess their future parental activity. Therefore, adjusting brood sex ratio to the level of male aggression could be adaptive. Our results indicate that the behavior of the partner could indeed be a significant determinant in brood sex ratio adjustment, which should not be overlooked in future studies. PMID:24973871

  2. The role of sexually explicit material in the sexual development of same-sex-attracted Black adolescent males.

    PubMed

    Arrington-Sanders, Renata; Harper, Gary W; Morgan, Anthony; Ogunbajo, Adedotun; Trent, Maria; Fortenberry, J Dennis

    2015-04-01

    Sexually explicit material (SEM) (including Internet, video, and print) may play a key role in the lives of Black same-sex sexually active youth by providing the only information to learn about sexual development. There is limited school- and/or family-based sex education to serve as models for sexual behaviors for Black youth. We describe the role SEM plays in the sexual development of a sample of Black same-sex attracted (SSA) young adolescent males ages 15-19. Adolescents recruited from clinics, social networking sites, and through snowball sampling were invited to participate in a 90-min, semi-structured qualitative interview. Most participants described using SEM prior to their first same-sex sexual experience. Participants described using SEM primarily for sexual development, including learning about sexual organs and function, the mechanics of same-gender sex, and to negotiate one's sexual identity. Secondary functions were to determine readiness for sex; to learn about sexual performance, including understanding sexual roles and responsibilities (e.g., "top" or "bottom"); to introduce sexual performance scripts; and to develop models for how sex should feel (e.g., pleasure and pain). Youth also described engaging in sexual behaviors (including condom non-use and/or swallowing ejaculate) that were modeled on SEM. Comprehensive sexuality education programs should be designed to address the unmet needs of young, Black SSA men, with explicit focus on sexual roles and behaviors that may be inaccurately portrayed and/or involve sexual risk-taking (such as unprotected anal intercourse and swallowing ejaculate) in SEM. This work also calls for development of Internet-based HIV/STI prevention strategies targeting young Black SSA men who may be accessing SEM. PMID:25677334

  3. The dermatoglyphic characteristics of transsexuals: is there evidence for an organizing effect of sex hormones.

    PubMed

    Slabbekoorn, D; van Goozen, S H; Sanders, G; Gooren, L J; Cohen-Kettenis, P T

    2000-05-01

    It has been proposed that gender identity and sexual orientation are influenced by the prenatal sex steroid milieu. Human dermatoglyphics and brain asymmetry have also been ascribed to prenatal hormone levels. This study investigated dermatoglyphics (total ridge count and finger ridge asymmetry) in 184 male-to-female transsexuals and 110 female-to-male transsexuals. In a subgroup, the relationship between dermatoglyphic asymmetry and spatial ability was tested. All investigations included controls. For all subjects hand preference and sexual orientation were noted. We hypothesized that the dermatoglyphics of male-to-female transsexuals would show similarities with control women and those of female-to-male transsexuals with control men. Our results showed a trend for a sex difference in total ridge count (P<.1) between genetic males and females, but no difference in directional asymmetry was found. Contrary to our expectations, the total ridge count and finger ridge asymmetry of transsexuals were similar to their genetic sex controls. Additionally, directional asymmetry was neither related to sexual orientation, nor to different aspects of spatial ability. In conclusion, we were unable to demonstrate that our chosen dermatoglyphic variables, total ridge count and finger ridge asymmetry are related to gender identity and sexual orientation in adult transsexuals. Hence, we found no support for a prenatal hormonal influence on these characteristics, at least insofar as dermatoglyphics may be regarded as a biological marker of organizing hormonal effects. PMID:10725613

  4. Does Sex (Female versus Male) Influence the Impact of Class Attendance on Examination Performance?

    ERIC Educational Resources Information Center

    Cortright, Ronald N.; Lujan, Heidi L.; Cox, Julie H.; DiCarlo, Stephen E.

    2011-01-01

    The "conventional wisdom" is that grades are related to class attendance, i.e., students who attend classes more frequently obtain better grades and class attendance dramatically contributes to enhanced learning. However, the influence of sex (female vs. male) on this relationship is understudied. Furthermore, there have been several studies…

  5. What Else Don't Real Men Do? Sex Role Orientation and Adjustment in College Males.

    ERIC Educational Resources Information Center

    Adams, Carol; Sherer, Mark

    Bem's androgyny theory predicts better psychological adjustment in androgynous males and females (those with a balance of masculine and feminine traits) than in traditionally masculine men or feminine women. However, recent research suggests that androgynous individuals have no advantage over masculine-typed individuals of either sex. To explore…

  6. Attraction between sexes: male-female gametocyte behaviour within a Leucocytozoon toddi (Haemosporida).

    PubMed

    Barraclough, Rosemary K; Duval, Linda; Talman, Arthur M; Ariey, Frédéric; Robert, Vincent

    2008-05-01

    Understanding the breeding systems of Plasmodium, and the closely related Haemoproteus and Leucocytozoon (Apicomplexa: Haemosporida), is fundamental to virulence and transmission research. We report an unusual binding behaviour between gametocytes of Leucocytozoon toddi. This aggregative behaviour was notably characterised by a disparity in the likelihood of clustering by female and male gametocytes. Thus, indicating a possible difference in the 'stickiness' of gametocytes per sex. Overall, 12% of gametocytes in this high-parasitaemia infection (0.269 gametocytes per 100 red blood cells (RBCs)) were incorporated into aggregations involving substantial contact. The gametocyte sexual combinations within aggregations varied significantly from expected according to the background 0.49 sex ratio within this sample, with female-female contacts occurring more and male-male contacts occurring less frequently than expected. A second L. toddi (identical for 709 bp of the cyt b mitochondrial gene) with lower parasitemia (0.035 gametocytes per 100 RBCs) showed no significant binding. Interestingly, the ratios of male gametocytes in both of these parasites were greater than expected under sex-ratio theory and similar to the 50% observed in species with syzygy breeding strategies. We discuss the ramifications of this observation in terms of sex-ratio theory and breeding strategies and provide speculative explanations for this unusual gametocyte behaviour. PMID:18297311

  7. Male-biased sex ratio in litters of Alpine marmots supports the helper repayment hypothesis

    Microsoft Academic Search

    Dominique Allaine; Francine Brondex; Laurent Graziani; Jacques Coulon; Irene Till-Bottraudb

    2000-01-01

    In a French population of Alpine marmots (Marmota marmota), the sex ratio at weaning was biased in favor of males. This bias also seemed to exist at birth. Under Fisher's equal allocation principle, this means that daughters should be more costly to produce than sons. Because the Alpine marmot can be considered a cooperative breeding species, we investigated whether the

  8. SEX RECOGNITION IN SURFACE AND CAVE DWELLING MALE ATLANTIC MOLLIES POECILIA MEXICANA

    E-print Network

    Schlupp, Ingo

    SEX RECOGNITION IN SURFACE AND CAVE DWELLING MALE ATLANTIC MOLLIES POECILIA MEXICANA (POECILIIDAE to recognizefemales in two surface and a cave dwelling population of a livebearing sh, Poecilia mexicana. In surface in two surface and a cave dwelling popula- tion of Atlantic mollies. Poecilia mexicana is widely

  9. MALE-BIASED SEX RATIOS IN LABORATORY REARINGS OF GYPSY MOTH PARASITOIDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male-biased sex ratios in populations of parasitic wasps used in biological control are undesirable, because a low ratio of females can prevent the establishment of introduced species or hinder commercial production of species used for augmentative control. This problem has arisen in the culture of...

  10. The effect of mood on opposite-sex judgments of males' commitment and females' sexual intent

    Microsoft Academic Search

    Mark Stokes

    Gender differences in perceptions of sexual intent and commitment have been the subject of formal and informal inquiry for considerable time. One evolutionary theory, Error Management Theory (EMT), predicts that opposite-sex perceptions of female sexual intent and male commitment intent reflect intrinsic biases that minimize gender-specific evolutionary costs. The results supporting these hypotheses were obtained from subjects regardless of mood.

  11. A case study of a male sex offender with zoosexual interests and behaviours

    Microsoft Academic Search

    D. T. Wilcox; C. M. Foss; M. L. Donathy

    2005-01-01

    This paper reviews assessment, treatment and supervision issues in relation to a high-risk, borderline functioning, male sex offender with zoosexual interests and behaviours. Mr Z was convicted of multiple sexual offences including rape, indecent assault and indecent exposure as well as actual and threatened bodily harm. He was convicted for two counts of attempted buggery of horses and he received

  12. OLFACTORY DISCRIMINATION OF SEX PHEROMONE STEREOISOMERS: CHIRALITY RECOGNITION BY PINK HIBISCUS MEALYBUG MALES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our previous field studies suggested that the two chiral centers that existed in sex pheromone of pink hibiscus mealybug, Maconellicoccus hirsutus, could elicit different male attractive responses. The chiral center in the acidic moiety of the ester seemed to be more critical than the alcoholic por...

  13. Sociodemographic characteristics and HIV risk behaviour patterns of male sex workers in Madrid, Spain

    Microsoft Academic Search

    M. J. Belza; A. Llácer; R. Mora; M. Morales; J. Castilla; L. de la Fuente

    2001-01-01

    This paper describes the sociodemographic and work characteristics, prevalence of HIV infection and associated risk behaviours among male sex workers (MSWs) in Madrid (Spain). Using an anonymous semi-structured questionnaire, educators attached to a mobile unit under a street-based prostitution programme surveyed 84 MSWs from several Madrid areas. Of the total surveyed: 35% were immigrants, mean age was 23 years, mean

  14. Sexual selection in an isopod with Wolbachia-induced sex reversal: males prefer real females

    Microsoft Academic Search

    J. Moreau; A. Bertin; Y. Caubet; T. Rigaud

    2001-01-01

    A variety of genetic elements encode traits beneficial to their own transmis- sion. Despite their 'selfish' behaviour, most of these elements are often found at relatively low frequencies in host populations. This is the case of intracytoplasmic Wolbachia bacteria hosted by the isopod Armadillidium vulgare that distort the host sex ratio towards females by feminizing the genetic males they infect.

  15. Adolescent and Young Adult Male Sex Offenders: Understanding the Role of Recidivism

    ERIC Educational Resources Information Center

    Riser, Diana K.; Pegram, Sheri E.; Farley, Julee P.

    2013-01-01

    The current review explores the complex paths that can lead to adolescent and young adult males becoming sexually abusive. Because sexual abuse is an ongoing issue in our society that is often oversimplified, this article distinguishes between the various risk factors that predict sexually abusive behavior and types of sex offenders, particularly…

  16. Sex differences in the functional organization of the brain for language

    Microsoft Academic Search

    R. Todd Constable; Pawel Skudlarski; Robert K. Fulbright; Richard A. Bronen; Jack M. Fletcher; Donald P. Shankweiler; Leonard Katz; John C. Gore

    1995-01-01

    A much debated question is whether sex differences exist in the functional organization of the brain for language *RF 1-4*. A long-held hypothesis posits that language functions are more likely to be highly lateralized in males and to be represented in both cerebral hemispheres in females (5,6), but attempts to demonstrate this have been inconclusive (7- 17). Here we use

  17. Social context, sexual risk perceptions and stigma: HIV vulnerability among male sex workers in Mombasa, Kenya.

    PubMed

    Okal, Jerry; Luchters, Stanley; Geibel, Scott; Chersich, Matthew F; Lango, Daniel; Temmerman, Marleen

    2009-11-01

    Knowledge about sexual practices and life experiences of men having sex with men in Kenya, and indeed in East Africa, is limited. Although the impact of male same-sex HIV transmission in Africa is increasingly acknowledged, HIV prevention initiatives remain focused largely on heterosexual and mother-to-child transmission. Using data from ten in-depth interviews and three focus group discussions (36 men), this analysis explores social and behavioural determinants of sexual risks among men who sell sex to men in Mombasa, Kenya. Analysis showed a range and variation of men by age and social class. First male same-sex experiences occurred for diverse reasons, including love and pleasure, as part of sexual exploration, economic exchange and coercion. Condom use is erratic and subject to common constraints, including notions of sexual interference and motivations of clients. Low knowledge compounds sexual risk taking, with a widespread belief that the risk of HIV transmission through anal sex is lower than vaginal sex. Traditional family values, stereotypes of abnormality, gender norms and cultural and religious influences underlie intense stigma and discrimination. This information is guiding development of peer education programmes and sensitisation of health providers, addressing unmet HIV prevention needs. Such changes are required throughout Eastern Africa. PMID:19484638

  18. Masculine Epigenetic Sex Marks of the CYP19A1/Aromatase Promoter in Genetically Male Chicken Embryonic Gonads Are Resistant to Estrogen-Induced Phenotypic Sex Conversion1

    PubMed Central

    Ellis, Haley L.; Shioda, Keiko; Rosenthal, Noël F.; Coser, Kathryn R.; Shioda, Toshi

    2012-01-01

    ABSTRACT Sex of birds is genetically determined through inheritance of the ZW sex chromosomes (ZZ males and ZW females). Although the mechanisms of avian sex determination remains unknown, the genetic sex is experimentally reversible by in ovo exposure to exogenous estrogens (ZZ-male feminization) or aromatase inhibitors (ZW-female masculinization). Expression of various testis- and ovary-specific marker genes during the normal and reversed gonadal sex differentiation in chicken embryos has been extensively studied, but the roles of sex-specific epigenetic marks in sex differentiation are unknown. In this study, we show that a 170-nt region in the promoter of CYP19A1/aromatase, a key gene required for ovarian estrogen biosynthesis and feminization of chicken embryonic gonads, contains highly quantitative, nucleotide base-level epigenetic marks that reflect phenotypic gonadal sex differentiation. We developed a protocol to feminize ZZ-male chicken embryonic gonads in a highly quantitative manner by direct injection of emulsified ethynylestradiol into yolk at various developmental stages. Taking advantage of this experimental sex reversal model, we show that the epigenetic sex marks in the CYP19A1/aromatase promoter involving DNA methylation and histone lysine methylation are feminized significantly but only partially in sex-converted gonads even when morphological and transcriptional marks of sex differentiation show complete feminization, being indistinguishable from gonads of normal ZW females. Our study suggests that the epigenetic sex of chicken embryonic gonads is more stable than the morphologically or transcriptionally characterized sex differentiation, suggesting the importance of the nucleotide base-level epigenetic sex in gonadal sex differentiation. PMID:22539680

  19. Common spontaneous sex-reversed XX males of the medaka Oryzias latipes.

    PubMed Central

    Nanda, Indrajit; Hornung, Ute; Kondo, Mariko; Schmid, Michael; Schartl, Manfred

    2003-01-01

    In the medaka, a duplicated version of the dmrt1 gene, dmrt1bY, has been identified as a candidate for the master male sex-determining gene on the Y chromosome. By screening several strains of Northern and Southern medaka we identified a considerable number of males with normal phenotype and uncompromised fertility, but lacking dmrt1bY. The frequency of such males was >10% in some strains and zero in others. Analysis for the presence of other Y-linked markers by FISH analysis, PCR, and phenotype indicated that their genotype is XX. Crossing such males with XX females led to a strong female bias in the offspring and also to a reappearance of XX males in the following generations. This indicated that the candidate male sex-determining gene dmrt1bY may not be necessary for male development in every case, but that its function can be taken over by so far unidentified autosomal modifiers. PMID:12586712

  20. Induction of Female-to–male Sex Change in the Honeycomb Grouper (Epinephelus merra) by 11-ketotestosterone Treatments

    Microsoft Academic Search

    Ramji Kumar Bhandari; Mohammad Ashraful Alam; Kiyoshi Soyano; Masaru Nakamura

    2006-01-01

    The honeycomb grouper, Epinephelus merra , is a protogynous hermaphrodite fish. Sex steroid hor- mones play key roles in sex change of this species. A significant drop in endogenous estradiol- 17? ? ? ? (E2) levels alone triggers female-to-male sex change, and the subsequent elevation of 11- ketotestosterone (11KT) levels correlates with the progression of spermatogenesis. To elucidate the role

  1. Male sex pheromone release and female mate choice in a butterfly.

    PubMed

    Andersson, Johan; Borg-Karlson, Anna-Karin; Vongvanich, Namphung; Wiklund, Christer

    2007-03-01

    In butterflies female mate choice is influenced by both visual and olfactory cues, the latter of which are important at close range. Males of the green-veined butterfly, Pieris napi, are known to release citral (mixture of geranial and neral, 1:1), but its role(s) and conditions of release are not known. Here, we show that male P. napi release citral when interacting with conspecific males, conspecific females, heterospecific males and also when alone. The amount of citral released correlated strongly with male flight activity, which explained more than 70% of the variation. This suggests that males do not exercise control over turning release on or off, but rather that citral is emitted as a passive physical process during flight. Electroantennogram experiments showed that female antennal response was ten times more sensitive to citral than male response. Females expressed acceptance behavior when exposed to models made with freshly excised male wings or those treated with citral following chemical extraction, but not to ones with extracted wings only. Hence, these behavioral and electrophysiological tests provide strong evidence that citral is a signal from the male directed to the female during courtship, and that it functions as a male sex pheromone. PMID:17337709

  2. Sex ratio shift in offspring of male fixed-wing naval aviation officers.

    PubMed

    Baczuk, Rebecca; Biascan, Anthony; Grossgold, Erik; Isaacson, Ari; Spencer, Joel; Wisotzky, Eric

    2009-05-01

    The concept that aviators father more daughters than sons is a persistent rumor within aviation circles. This study was designed to determine the sex ratio among offspring of male fixed-wing naval aviation officers and to look for associations between sex ratio, flight hours, and mission. Through an online questionnaire, we asked for gender and date of birth of the child, monthly flying hours during the 4 months before conception, and the type of aircraft flown. Analysis revealed that the sex ratio of offspring from all participants in our study was not statistically significantly different from the general population. However, a significant sex ratio shift favoring daughters existed as the officer flew more hours during the 11th month before birth. As the implications of this are unknown, officers should be counseled that their chance of having a son or daughter is no different than the general population. PMID:20731285

  3. When sex work becomes your everything: The complex linkages between economy and affection among male sex workers in Peru

    PubMed Central

    Bayer, Angela M.; Garvich, Mijail; Díaz, David A.; Sánchez, Hugo; García, Patricia J.; Coates, Thomas J.

    2014-01-01

    In Peru, there are few studies on male sex workers (MSWs) and existing studies explore limited sub-groups or offer limited information about MSWs’ perspectives. This study provides in-depth perspectives from 40 MSWs who work in downtown Lima (Cercado) and in surrounding urban neighborhoods (non-Cercado) through interviews on their identities, lives and HIV/STI risks and vulnerabilities. Findings are that entry into sex work links economy and affection, particularly among Cercado MSWs. Continued sex work cements this link, making it difficult to exit sex work and establish goals. Ties between economics and affections influence MSWs’ perceived HIV/STI risks, vulnerabilities and prevention practices. Although Cercado MSWs report higher HIV/STI risks and vulnerabilities than non-Cercado peers, they report fewer prevention practices given inability to buy condoms and acceptance of client offers of higher payment, especially clients they feel affection for. MSWs need support to strengthen their self-perceptions and define and pursue their goals in order to improve their HIV/STI prevention practices, health and well-being. PMID:24368712

  4. SEX DETERMINATION. A male-determining factor in the mosquito Aedes aegypti.

    PubMed

    Hall, Andrew Brantley; Basu, Sanjay; Jiang, Xiaofang; Qi, Yumin; Timoshevskiy, Vladimir A; Biedler, James K; Sharakhova, Maria V; Elahi, Rubayet; Anderson, Michelle A E; Chen, Xiao-Guang; Sharakhov, Igor V; Adelman, Zach N; Tu, Zhijian

    2015-06-12

    Sex determination in the mosquito Aedes aegypti is governed by a dominant male-determining factor (M factor) located within a Y chromosome-like region called the M locus. Here, we show that an M-locus gene, Nix, functions as an M factor in A. aegypti. Nix exhibits persistent M linkage and early embryonic expression, two characteristics required of an M factor. Nix knockout with clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 resulted in largely feminized genetic males and the production of female isoforms of two key regulators of sexual differentiation: doublesex and fruitless. Ectopic expression of Nix resulted in genetic females with nearly complete male genitalia. Thus, Nix is both required and sufficient to initiate male development. This study provides a foundation for mosquito control strategies that convert female mosquitoes into harmless males. PMID:25999371

  5. Stigma, social inequality, and HIV risk disclosure among Dominican male sex workers?

    PubMed Central

    Padilla, Mark; Castellanos, Daniel; Guilamo-Ramos, Vincent; Reyes, Armando Matiz; Sánchez Marte, Leonardo E.; Soriano, Martha Arredondo

    2010-01-01

    Some quantitative behavioral studies in the USA have concluded that bisexually behaving Latino men are less likely than White men to disclose to their female partners that they have engaged in same-sex risk behavior and/or are HIV-positive, presumably exposing female partners to elevated risk for HIV infection. Nevertheless, very little theoretical or empirical research has been conducted to understand the social factors that promote or inhibit sexual risk disclosure among Latino men who have sex with men (MSM), and much of the existing literature has neglected to contextualize disclosure patterns within broader experiences of stigma and social inequality. This paper examines decisions about disclosure of sex work, same-sex behavior, and sexual risk for HIV among male sex workers in two cities in the Dominican Republic. Data derive from long-term ethnography and qualitative in-depth interviews with 72 male sex workers were used to analyze the relationships among experiences of stigma, social inequality, and patterns of sexual risk disclosure. Thematic analysis of interviews and ethnographic evidence revealed a wide range of stigma management techniques utilized by sex workers to minimize the effects of marginality due to their engagement in homosexuality and sex work. These techniques imposed severe constraints on men’s sexual risk disclosure, and potentially elevated their own and their female partners’ vulnerability to HIV infection. Based on the study’s findings, we conclude that future studies of sexual risk disclosure among ethnic minority MSM should avoid analyzing disclosure as a decontextualized variable, and should seek to examine sexual risk communication as a dynamic social process constrained by hierarchical systems of power and inequality. PMID:18410986

  6. Temperature-dependent sex determination: upregulation of SOX9 expression after commitment to male development.

    PubMed

    Western, P S; Harry, J L; Graves, J A; Sinclair, A H

    1999-03-01

    In mammals, birds and reptiles the morphological development of the gonads appear to be conserved. This conservation is evident despite the different sex determining switches employed by these vertebrate groups. Mammals exhibit chromosomal sex determination (CSD) where the key sex determining switch is the Y-linked gene, SRY. Although SRY is the trigger for testis determination in mammals, it is not conserved in other vertebrate groups. However, a gene closely related to SRY, the highly conserved transcription factor, SOX9, plays an important role in the testis pathway of mammals and birds. In contrast to the CSD mechanism evident in mammals and birds, many reptiles exhibit temperature dependent sex determination (TSD) where the egg incubation temperature triggers sex determination. Here we examine the expression of SOX9 during gonadogenesis in the American alligator, (Alligator mississippiensis), a reptile that exhibits TSD. Alligator SOX9 is expressed in the embryonic testis but not in the ovary. However, the timing of SOX9 upregulation in the developing testis is not consistent with a role for this gene in the early stages of alligator sex determination. Since SOX9 upregulation in male embryos coincides with the structural organisation of the testis, SOX9 may operate farther downstream in the vertebrate sex differentiation pathway than previously postulated. PMID:10090144

  7. Neonatal MeCP2 is important for the organization of sex differences in vasopressin expression

    PubMed Central

    Forbes-Lorman, Robin M; Rautio, Jared J; Kurian, Joseph R; Auger, Anthony P

    2012-01-01

    Several neurodevelopmental disorders are marked by atypical Methyl-CpG-binding protein 2 (MeCP2) expression or function; however, the role of MeCP2 is complex and not entirely clear. Interestingly, there are sex differences in some of these disorders, and it appears that MeCP2 has sex-specific roles during development. Specifically, recent data indicate that a transient reduction in MeCP2 within developing amygdala reduces juvenile social play behavior in males to female-typical levels. These data suggest that MeCP2 within the amygdala is involved in programming lasting sex differences in social behavior. In the present study, we infused MeCP2 or control siRNA into the amygdala of male and female rats during the first three days of postnatal life in order to assess the impact of a transient reduction in MeCP2 on arginine vasopressin (AVP), a neural marker that is expressed differentially between males and females and is linked to a number of social behaviors. The expression of AVP, as well as several other genes, was measured in two-week old and adult animals. Two-week old males expressed more AVP and galanin mRNA in the amygdala than females, and a transient reduction in MeCP2 eliminated this sex difference by reducing the expression of both gene products in males. A transient reduction in MeCP2 also decreased androgen receptor (AR) mRNA in two-week old males. In adulthood, control males had more AVP-immunoreactive (AVP-ir) cells than females in the centromedial amygdala (CMA), bed nucleus of the striaterminalis (BST) and in the fibers that project from these cells to the lateral septum (LS). A transient reduction in MeCP2 eliminated this sex difference. Interestingly, there were no lasting differences in galanin or AR levels in adulthood. Reducing MeCP2 levels during development did not alter estrogen receptor?, neurofilament or Foxg1. We conclude that a transient reduction in MeCP2 expression in the developing male amygdala has a transient impact on galanin and AR expression but a lasting impact on AVP expression, highlighting the importance of MeCP2 in organizing sex differences in the amygdala. PMID:22430799

  8. Syphilis-related perceptions not associated with risk behaviors among men who have sex with men having regular male sex partner(s) in Nanjing, China.

    PubMed

    Wang, Zixin; Lau, Joseph T F; Hao, Chun; Yang, Haitao; Huan, Xiping; Yan, Hongjing; Guan, Wenhui

    2013-08-01

    The prevalence of HIV among men who sex with men (MSM)has been increasing sharply in China. The prevalence of unprotected anal intercourse (UAI)among them is very high, especially when male regular sex partners are involved. Many MSM having regular sex partners are engaged in multiple sex partnerships, which often involved UAI. This study interviewed 168 MSM in Nanjing, China, having had anal intercourse with at least one male regular sex partner in the last six months. Amongst the participants, 52.4% reported having had UAI with male regular sex partners whilst 50.0% reported multiple male sex partnerships in the last six months. Multivariate analysis showed that monthly personal income higher than 2000 RMB (multivariate OR = 0.49, 95% CI: 0.26-0.96), HIV antibody testing in the last year (multivariate OR = 0.19, 95% CI: 0.06-0.60), sexual position being both insertive and receptive during anal sex with male sex partners in general (multivariate OR = 0.43, 95% CI: 0.18-0.99; reference group: with receptive position only) were associated with lower likelihoods of UAI. Syphilis-related perceptions, including knowledge, cognitions (perceived susceptibility, perceived severity, self-efficacy in avoiding syphilis infection and perceived infectivity and perceived syphilis-related norms among MSM in general)were not associated with risk behaviors (UAI and multiple male sex partnerships). Our sampled MSM are exposed to very high risk of HIV/STD transmission. We found no association between syphilis-related perceptions and the two types of risk behaviors. Future studies are warranted to understand such associations in the context of sexual intercourse with non-regular sex partners among MSM. PMID:23215455

  9. Tuning breadth and sex-specific sensitivity in chemosensory neurons of male and female Uca pugnax.

    PubMed

    Weissburg, M J

    1999-09-01

    Chemosensory neurons of female fiddler crabs (genus Uca) display greater sensitivity to mixtures of food-related stimuli than do neurons in males. This phenomenon represents an interesting contrast to other sex-specific systems, which tend to be in response to cues associated with mating and parental care. This study examined the responses of chemosensory neurons in males and females to ten individual stimuli to determine if sex-specific responses were restricted to a few key compounds, or if the heightened sensitivity of females was broadly distributed. Neurons in males and females responded well to all stimuli, and although fiddler crabs are primarily herbivorous, highly efficacious physiological stimulants included amino acids and amines as well as carbohydrates most closely associated with plant material. The chemosensory neurons are characterized by broad tuning and relatively high response thresholds, when compared to other crustaceans. Most importantly, the investigations revealed a robust pattern in which female neurons displayed elevated responses to all stimuli. Tuning breadth was not shown to be sex-specific, nor were there detectable differences in over-all response profiles. The most likely explanation for these patterns is that the broad sex-specificity in Uca is produced via fundamental alterations in cellular properties associated with chemosensory transduction. PMID:10573864

  10. Effects of male sex hormones on gender identity, sexual behavior, and cognitive function.

    PubMed

    Zhu, Yuan-shan; Cai, Li-qun

    2006-04-01

    Androgens, the male sex hormones, play an essential role in male sexual differentiation and development. However, the influence of these sex hormones extends beyond their roles in sexual differentiation and development. In many animal species, sex hormones have been shown to be essential for sexual differentiation of the brain during development and for maintaining sexually dimorphic behavior throughout life. The principals of sex determination in humans have been demonstrated to be similar to other mammals. However, the hormonal influence on sexual dimorphic differences in the nervous system in humans, sex differences in behaviors, and its correlations with those of other mammals is still an emerging field. In this review, the roles of androgens in gender and cognitive function are discussed with the emphasis on subjects with androgen action defects including complete androgen insensitivity due to androgen receptor mutations and 5alpha-reductase-2 deficiency syndromes due to 5alpha-reductase-2 gene mutations. The issue of the complex interaction of nature versus nurture is addressed. PMID:16706106

  11. Sex steroids in serum of prepubertal male and female horses and correlation with bone characteristics.

    PubMed

    Lemazurier, Emmanuel; Toquet, Marie Pierre; Fortier, Guillaume; Séralini, Gilles Eric

    2002-04-01

    We used radioimmunoassay (RIA) to measure monthly serum levels of unconjugated and conjugated sex steroids (testosterone T, androstenedione A, estradiol E(2), and estrone E(1)) in 4 male and 4 female foals during their first year of life. Maximal production of sex steroids was detected from April to August with hormonal peaks, corresponding to the natural breeding season in adults. In males, only A levels were more steady. Total estrogens (unconjugated plus conjugated E(2) and E(1)) were the major steroids in immature males in contrast to adults. Estrogens generally peaked in young females before males; the major estrogen was E(1), and total estrogens overtook total androgens (unconjugated and conjugated T and unconjugated A). We also sampled 3 male and 3 female foals with bone alterations in adulthood. For all animals, serum levels of four bone formation markers were obtained: osteocalcin (O), hydroxyproline (HP), and alkaline phosphatase (AP), and a radiographic score was determined. Only male foals with normal skeletal frame (good radiographic score GRS) in adulthood showed a correlation (P < 0.01) between the distribution frequency of each bone formation marker and unconjugated E(2) or E(1) levels; this finding highlighted the role of unconjugated estrogens in bone maturation in horses, since this was not found in the groups with bone alterations. In females, the threshold of estrogen synthesis and sensitivity was probably sufficient to be a nonlimiting factor at this stage of development. Our results strongly suggest a differential regulation of the estrogen/androgen balance in horses according to sex, sexual maturation, and photoperiod. Moreover, estrogens appear to be crucial for skeletal development in male colts, and these steroids are good modulators of skeletal frame characteristics in adulthood. PMID:11958792

  12. Environmental conditions affect sex expression in monoecious, but not in male and female plants of Urtica dioica

    Microsoft Academic Search

    Grit A. Glawe; Tom J. de Jong

    2005-01-01

    Urtica dioica is a sub-dioecious plant species, i.e. males and females coexist with monoecious individuals. Under standard conditions, seed sex ratio (SSR, fraction of males) was found to vary significantly among seed samples collected from female plants originating from the same population (0.05–0.76). As a first step, we investigated the extent to which SSR and sex expression of male, female,

  13. Sex disparity in colonic adenomagenesis involves promotion by male hormones, not protection by female hormones

    PubMed Central

    Amos-Landgraf, James M.; Heijmans, Jarom; Wielenga, Mattheus C. B.; Dunkin, Elisa; Krentz, Kathy J.; Clipson, Linda; Ederveen, Antwan G.; Groothuis, Patrick G.; Mosselman, Sietse; Muncan, Vanesa; Hommes, Daniel W.; Shedlovsky, Alexandra; Dove, William F.; van den Brink, Gijs R.

    2014-01-01

    It recently has been recognized that men develop colonic adenomas and carcinomas at an earlier age and at a higher rate than women. In the ApcPirc/+ (Pirc) rat model of early colonic cancer, this sex susceptibility was recapitulated, with male Pirc rats developing twice as many adenomas as females. Analysis of large datasets revealed that the ApcMin/+ mouse also shows enhanced male susceptibility to adenomagenesis, but only in the colon. In addition, WT mice treated with injections of the carcinogen azoxymethane (AOM) showed increased numbers of colonic adenomas in males. The mechanism underlying these observations was investigated by manipulation of hormonal status. The preponderance of colonic adenomas in the Pirc rat model allowed a statistically significant investigation in vivo of the mechanism of sex hormone action on the development of colonic adenomas. Females depleted of endogenous hormones by ovariectomy did not exhibit a change in prevalence of adenomas, nor was any effect observed with replacement of one or a combination of female hormones. In contrast, depletion of male hormones by orchidectomy (castration) markedly protected the Pirc rat from adenoma development, whereas supplementation with testosterone reversed that effect. These observations were recapitulated in the AOM mouse model. Androgen receptor was undetectable in the colon or adenomas, making it likely that testosterone acts indirectly on the tumor lineage. Our findings suggest that indirect tumor-promoting effects of testosterone likely explain the disparity between the sexes in the development of colonic adenomas. PMID:25368192

  14. Variation in lifetime male fitness in Ipomopsis aggregata: tests of sex allocation theory.

    PubMed

    Campbell, D R

    1998-09-01

    Sex allocation theory assumes that a shift in allocation of resources to male function both increases male fitness and decreases female fitness. Moreover, the shapes of these fitness gain functions determine whether hermaphroditism or another breeding system is evolutionarily stable. In this article, I first outline information needed to measure these functions in flowering plants. I then use paternity analysis to describe the shapes of the fitness gain functions in natural populations of the hermaphroditic herb Ipomopsis aggregata. I also explore the relationships of male fitness (number of seeds sired) and female fitness (number of seeds produced) to the number of flowers produced by a plant. Plants with greater investment of biomass in the androecium, compared to the gynoecium and seeds, showed increased success at siring seeds, assumed by the models. That sex allocation trait, however, explained only 9% of the variance in estimates of male fitness. The shapes of the fitness gain functions were consistent with theoretical expectations for a hermaphroditic plant, but the model predicted a more female-biased evolutionarily stable strategy (ESS) allocation than was observed. These results lend only partial support the classical sex allocation model. PMID:18811443

  15. HIV and STI prevalence and risk factors among male sex workers and other men who have sex with men in Nairobi, Kenya.

    PubMed

    Muraguri, Nicholas; Tun, Waimar; Okal, Jerry; Broz, Dita; Raymond, H Fisher; Kellogg, Timothy; Dadabhai, Sufia; Musyoki, Helgar; Sheehy, Meredith; Kuria, David; Kaiser, Reinhard; Geibel, Scott

    2015-01-01

    : Previous surveys of men who have sex with men (MSM) in Africa have not adequately profiled HIV status and risk factors by sex work status. MSM in Nairobi, Kenya, were recruited using respondent-driven sampling, completed a behavioral interview, and were tested for HIV and sexually transmitted infections. Overlapping recruitment among 273 male sex workers and 290 other MSM was common. Sex workers were more likely to report receptive anal sex with multiple partners (65.7% versus 18.0%, P < 0.001) and unprotected receptive anal intercourse (40.0% versus 22.8%, P = 0.005). Male sex workers were also more likely to be HIV infected (26.3% versus 12.2%, P = 0.007). PMID:25501346

  16. Female-Released Sex Pheromones Mediating Courtship Behavior in Lysiphlebus testaceipes Males

    PubMed Central

    Lo Pinto, Mirella; Cangelosi, Benedetta; Colazza, Stefano

    2013-01-01

    Ethological aspects and chemical communication at close-range between the sexes of Lysiphlebus testaceipes Cresson (Hymenoptera: Braconidae) have been investigated through behavioral bioassays and chemical analysis. The attractiveness toward males of whole-body extracts of females and males in hexane and acetone was evaluated, adopting male fanning behavior as a key behavioral component. Also, the activity of polar and nonpolar fraction of female-body extract in hexane obtained using solid-phase extraction technique was investigated. In order to identify cuticular compounds, male and female whole-body extracts with hexane and acetone were analyzed by gas chromatography-mass spectrometry. The results showed that males exhibit a behavior including 4 phases when exposed to virgin females: premount, mount, copulation, and post-copulation. A preliminary courtship of the male included wing fanning, an extension and vibration of the wings for 1 to 2 seconds. Also, some original aspects not described for other species were carried out. The average duration of the entire sequence of events was 138.80 ± 19.51 sec. Also, males displayed significantly more wing fanning behavior in response to female whole-body hexane extracts (70.83%) than female whole-body acetone extracts (33.3%). Furthermore, males did not respond to male-body extracts or to the control (pure hexane and acetone), suggesting that the sex pheromone is composed of cuticular hydrocarbons that are also involved in the male courtship behavior. When hexane extracts of whole females were fractionated on silica gel and exposed to males, more activity was recorded for the nonpolar fraction (50.0%) than the polar fraction (27.7%), but no significant statistical difference was found. Significant differences were detected comparing the control (not fractionated extract) with the polar fraction, but not with the nonpolar fraction. A homologous series of n-alkanes with chain lengths from C19 to C30 carbon atoms was identified and quantified in the solvent extracts of wasp males and females. Between male and female extracts, there was a statistically significant difference in the average quantity of some of these hydrocarbons, such as C27, C28, and C29. PMID:23906069

  17. Organic Elemental Composition in Fingernail Plates Varies between Sexes and Changes with Increasing Age in Healthy Humans

    Microsoft Academic Search

    Manuela Dittmar; Willi Dindorf; Arun Banerjee

    2008-01-01

    Background: Keratin, an ?-helical fibrous protein, is the primary component of human nail plates. No data on age-related changes in healthy subjects are present. Objective: This study investigated whether keratin amount and composition, as indicated by organic elemental composition of fingernails, varies with aging and between sexes. Methods: Nail clippings from 225 healthy individuals (93 males, 132 females), aged 20–90

  18. Selection on male sex pheromone composition contributes to butterfly reproductive isolation.

    PubMed

    Bacquet, P M B; Brattström, O; Wang, H-L; Allen, C E; Löfstedt, C; Brakefield, P M; Nieberding, C M

    2015-04-01

    Selection can facilitate diversification by inducing character displacement in mate choice traits that reduce the probability of maladaptive mating between lineages. Although reproductive character displacement (RCD) has been demonstrated in two-taxa case studies, the frequency of this process in nature is still debated. Moreover, studies have focused primarily on visual and acoustic traits, despite the fact that chemical communication is probably the most common means of species recognition. Here, we showed in a large, mostly sympatric, butterfly genus, a strong pattern of recurrent RCD for predicted male sex pheromone composition, but not for visual mate choice traits. Our results suggest that RCD is not anecdotal, and that selection for divergence in male sex pheromone composition contributed to reproductive isolation within the Bicyclus genus. We propose that selection may target olfactory mate choice traits as a more common sensory modality to ensure reproductive isolation among diverging lineages than previously envisaged. PMID:25740889

  19. [Genetics and endocrinology of male sex differentiation: application to molecular study of male pseudohermaphroditism].

    PubMed

    Sultan, C; Lumbroso, S; Poujol, N; Boudon, C; Georget, V; Térouanne, B; Belon, C; Lobaccaro, J M

    1995-01-01

    The various processes involved in sexual differentiation have been considerably clarified over the last few years through advances in biochemistry and molecular genetics. The cloning of the gene responsible for testicular determination SRY, of the anti-Müllerian hormone and anti-Müllerian hormone receptor genes, of the several steroidogenic enzymes genes, of the 5 alpha-reductase type 2 gene and of the androgen receptor gene has permitted to elucidate the molecular defects causing abnormal sexual differentiation. These data have brought a substantial impact on the understanding of human male sexual differentiation and its main disorders. PMID:8673622

  20. Birth order and sibling sex ratio in two samples of Dutch gender-dysphoric homosexual males

    Microsoft Academic Search

    Ray Blanchard; Kenneth J. Zucker; Petty T. Cohen-Kettenis; Louis J. G. Gooren; J. Michael Bailey

    1996-01-01

    Two studies were undertaken to confirm the previous findings that homosexual men in general tend to have a later than expected\\u000a birth order and that extremely feminine homosexual men also tend to have a higher than expected proportion of brothers (i.e.\\u000a a highersibling sex ratio). Subjects in Study 1 were Dutch, adult and adolescent, biological male patients with gender dysphoria

  1. Sex ratio meiotic drive as a plausible evolutionary mechanism for hybrid male sterility.

    PubMed

    Zhang, Linbin; Sun, Tianai; Woldesellassie, Fitsum; Xiao, Hailian; Tao, Yun

    2015-03-01

    Biological diversity on Earth depends on the multiplication of species or speciation, which is the evolution of reproductive isolation such as hybrid sterility between two new species. An unsolved puzzle is the exact mechanism(s) that causes two genomes to diverge from their common ancestor so that some divergent genes no longer function properly in the hybrids. Here we report genetic analyses of divergent genes controlling male fertility and sex ratio in two very young fruitfly species, Drosophila albomicans and D. nasuta. A majority of the genetic divergence for both traits is mapped to the same regions by quantitative trait loci mappings. With introgressions, six major loci are found to contribute to both traits. This genetic colocalization implicates that genes for hybrid male sterility have evolved primarily for controlling sex ratio. We propose that genetic conflicts over sex ratio may operate as a perpetual dynamo for genome divergence. This particular evolutionary mechanism may largely contribute to the rapid evolution of hybrid male sterility and the disproportionate enrichment of its underlying genes on the X chromosome--two patterns widely observed across animals. PMID:25822261

  2. Sex Ratio Meiotic Drive as a Plausible Evolutionary Mechanism for Hybrid Male Sterility

    PubMed Central

    Zhang, Linbin; Xiao, Hailian; Tao, Yun

    2015-01-01

    Biological diversity on Earth depends on the multiplication of species or speciation, which is the evolution of reproductive isolation such as hybrid sterility between two new species. An unsolved puzzle is the exact mechanism(s) that causes two genomes to diverge from their common ancestor so that some divergent genes no longer function properly in the hybrids. Here we report genetic analyses of divergent genes controlling male fertility and sex ratio in two very young fruitfly species, Drosophila albomicans and D. nasuta. A majority of the genetic divergence for both traits is mapped to the same regions by quantitative trait loci mappings. With introgressions, six major loci are found to contribute to both traits. This genetic colocalization implicates that genes for hybrid male sterility have evolved primarily for controlling sex ratio. We propose that genetic conflicts over sex ratio may operate as a perpetual dynamo for genome divergence. This particular evolutionary mechanism may largely contribute to the rapid evolution of hybrid male sterility and the disproportionate enrichment of its underlying genes on the X chromosome – two patterns widely observed across animals. PMID:25822261

  3. Weed Killer Deforms Sex Organs in Frogs, Study Finds

    NSDL National Science Digital Library

    Associated Press.

    This Web site discusses current research findings surrounding the use of the weed killer, atrazine, and sex organ deformities in frogs exposed to it. The article from the New York Times summarizes the recent research report; free registration is required to view it. This site reports focus on the potential impact of atrazine on humans, but they do raise it as an important question.

  4. Differential Recruitment and Control: The Sex Structuring of Organizations

    ERIC Educational Resources Information Center

    Acker, Joan; Van Houten, Donald R.

    1974-01-01

    Contends that sex differences in organizational participation are related to (1) differential recruitment of women into jobs requiring dependence and passivity; (2) selective recruitment of particularly compliant women into these jobs; and (3) control mechanisms used in organizations for women, which reinforce control mechanisms to which they are…

  5. Sex Education for Male Adolescent Sex Offenders in a Group Setting Led by General Psychiatry Residents: A Literature Review and Example in Practice

    Microsoft Academic Search

    R. Gregg Dwyer; Mary S. Boyd

    2009-01-01

    Male adolescents have been credited with a significant percentage of sex crimes in recent years. They are a heterogeneous population with offenses spanning the same range found among adult offenders. A lack of interpersonal social skills relevant to intimate relationships and inaccurate knowledge regarding appropriate sexual behaviors contribute to the sexual offending by some adolescent males. To address these shortcomings,

  6. Sex chromosome pre-reduction in male meiosis of Lethocerus patruelis (Stål, 1854) (Heteroptera, Belostomatidae) with some notes on the distribution of the species

    PubMed Central

    Grozeva, Snejana; Kuznetsova, Valentina G.; Simov, Nikolay; Langourov, Mario; Dalakchieva, Svetla

    2013-01-01

    Abstract The karyotype and meiosis in males of giant water bug Lethocerus patruelis (Heteroptera: Belostomatidae: Lethocerinae) were studied using standard and fluorochrome (CMA3 and DAPI) staining of chromosomes. The species was shown to have 2n = 22A + 2m + XY where 2m are a pair of microchromosomes. NORs are located in X and Y chromosomes. Within Belostomatidae, Lethocerus patruelis is unique in showing sex chromosome pre-reduction in male meiosis, with the sex chromosomes undergoing reductional division at anaphase I and equational division at anaphase II. Cytogenetic data on the family Belostomatidae are summarized and compared. In addition, the structure of the male internal reproductive organs of Lethocerus patruelis is presented, the contemporary distribution of Lethocerus patruelis in Bulgaria and in the northern Aegean Islands is discussed, and the first information about the breeding and nymphal development of this species in Bulgaria is provided. PMID:24039515

  7. Same-sex sexual behaviors among male migrants in a context of male "marriage squeeze": results from an exploratory survey in urban Xi'an, China.

    PubMed

    Yang, Xueyan; Attané, Isabelle; Li, Shuzhuo; Yang, Bo

    2012-11-01

    The male marriage squeeze in China may increase the prevalence of male same-sex sexual behaviors among unmarried male migrants who lack stable female sexual partners. The same-sex sexual behaviors among unmarried male migrants appear to be at high risk of transmission of human immunodeficiency virus (HIV) and sexually transmitted infections (STIs), mainly because of a lack of knowledge of these diseases. Using data from the "Survey on Reproductive Health and Family Life of Migrant Male Bachelors in Urban Areas" conducted in Xi'an City, Shaanxi Province, in December 2009 and January 2010, this study compares same-sex sexual behaviors of unmarried with that of married male migrants (including married but separated men who are migrating without their spouse or partner and cohabitating men who are migrating with their spouse or partner). It is reported that the prevalence of same-sex sexual behaviors among unmarried males reaches 11%, more than twice the 5.1% reported by married but separated men and thrice the 3.8% reported by cohabitating men. It also appears that the same-sex sexual behaviors is significantly associated with men's attitudes toward same-sex sexual behaviors (odds ratio = 1.59, p < .001), toward life-long bachelorhood (odds ratio = 1.35, p < .01), and with marital status (odds ratio = 0.37, p < .01). The frequency of condom use appears to be higher among unmarried men than among men who are married, whether or not they migrated with their wives, and is significantly associated with scores on knowledge about HIV/AIDS (estimated coefficient = .12, p < .001) and STIs (estimated coefficient = .22, p < .01). It is also associated with the likelihood of same-sex sexual behaviors (estimated coefficients = .83, p < .01) and marital status (estimated coefficients for married but separated = -.50, p < .05; estimated coefficients for cohabitating = -.77, p < .001). PMID:22782362

  8. Sex steroid hormones modulate responses to social challenge and opportunity in males of the monogamous convict cichlid, Amatitliana nigrofasciata.

    PubMed

    Sessa, Anna K; Harris, Rayna M; Hofmann, Hans A

    2013-08-01

    Steroid hormones play an important role in modulating behavioral responses to various social stimuli. It has been suggested that variation in the hormonal regulation of behavior across species is associated with social organization and/or mating system. In order to further elucidate the interplay of hormones and behavior in social situations, we exposed males of the monogamous convict cichlid Amatitliana nigrofasciata to three social stimuli: gravid female, intruder male, and a nonsocial stimulus. We used a repeated measure design to create behavioral profiles and explore how sex steroid hormones respond to and regulate social behavior. Results show distinct behavioral responses to different social situations, with circulating 11-ketotestosterone increasing in response to social stimuli. Pharmacological manipulations using specific androgen and estrogen receptor agonists and antagonists exposed complex control over digging behavior in the social opportunity context. In the social challenge context, aggressive behaviors decreased in response to blocking the androgen receptor pathway. Our results extend our understanding of sex steroid regulation of behavioral responses to social stimulation. PMID:23651580

  9. Sex-specific visual performance: female lizards outperform males in motion detection

    PubMed Central

    Nava, Saúl S.; Conway, Mirela; Martins, Emília P.

    2009-01-01

    In animal communication, complex displays usually have multiple functions and, male and female receivers often differ in their utilization and response to different aspects of these displays. The perceptual variability hypothesis suggests that different aspects of complex signals differ in their ability to be detected and processed by different receivers. Here, we tested whether receiver male and female Sceloporus graciosus lizards differ in visual motion detection by measuring the latency to the visual grasp response to a motion stimulus. We demonstrate that in lizards that largely exhibit complex motions as courtship signals, female lizards are faster than males at visually detecting motion. These results highlight that differential signal utilization by the sexes may be driven by variability in the capacity to detect different display properties. PMID:19656865

  10. Sex-specific visual performance: female lizards outperform males in motion detection.

    PubMed

    Nava, Saúl S; Conway, Mirela; Martins, Emília P

    2009-12-23

    In animal communication, complex displays usually have multiple functions and, male and female receivers often differ in their utilization and response to different aspects of these displays. The perceptual variability hypothesis suggests that different aspects of complex signals differ in their ability to be detected and processed by different receivers. Here, we tested whether receiver male and female Sceloporus graciosus lizards differ in visual motion detection by measuring the latency to the visual grasp response to a motion stimulus. We demonstrate that in lizards that largely exhibit complex motions as courtship signals, female lizards are faster than males at visually detecting motion. These results highlight that differential signal utilization by the sexes may be driven by variability in the capacity to detect different display properties. PMID:19656865

  11. The value of outside support for male and female politicians involved in a political sex scandal.

    PubMed

    Stewart, Dennis D; Rose, Roger P; Rosales, Felixia M; Rudney, Philip D; Lehner, Tasha A; Miltich, Gemma; Snyder, Cassie; Sadecki, Brianna

    2013-01-01

    This research examined how third party statements impact the evaluation of male and female politicians caught in a scandal (i.e., extramarital affair). Governor's sex was crossed with three types of support statements: third party supportive (TPS), third party non-supportive (TPNS), and governor self-supportive (GSS). In Experiment 1, a female politician was evaluated more positively than a male politician. The TPS and the GSS conditions were both evaluated more positively than the TPNS condition. Experiment 2's design was similar to Experiment l's, except it involved multiple affairs. In Experiment 2, participants used the third party's statements as an information source and thus reduced their use of gender stereotypes in the TPS and TPNS conditions compared to the GSS condition. We also found that male respondents gave more negative evaluations of the female governor than female respondents. Implications for the gender stereotype and social influence literatures are discussed. PMID:23724705

  12. Androstenedione may organize or activate sex-reversed traits in female spotted hyenas.

    PubMed Central

    Glickman, S E; Frank, L G; Davidson, J M; Smith, E R; Siiteri, P K

    1987-01-01

    Spotted hyenas (Crocuta crocuta Erxleben) present a unique syndrome of reversal in behavioral and anatomical distinction between the sexes: females are heavier and more aggressive than males and dominant over them. The female's external genitalia include a false scrotum and a fully erectile pseudopenis through which mating and birth take place. Results of studies of circulating testosterone levels in wild spotted hyenas do not account for the "male-like" characteristics of the female. Androstenedione, however, is consistently higher in females than in males, particularly during early infancy. Experiments on rodents show that androstenedione can be a potent organizer of anatomical and behavioral differentiation. This study suggests that it may also produce the profound virilization of female spotted hyenas. PMID:3472215

  13. Carotenoid-Based Ornaments of Female and Male American Goldfinches (Spinus tristis) Show Sex-Specific Correlations

    E-print Network

    Murphy, Troy G.

    348 Carotenoid-Based Ornaments of Female and Male American Goldfinches (Spinus tristis) Show Sex of carotenoid-based bill and plumage ornamentation in Amer- ican goldfinches Spinus tristis, a species in which

  14. The Role of Androgens in Male Pregnancy and Female Competitive Behavior in a Sex Role Reversed Pipefish

    E-print Network

    Scobell, Sunny Kay

    2012-02-14

    The sex-role reversal and male pregnancy found in syngnathids are highly unusual traits in vertebrates. Reproductive hormones likely influence development and regulation of these traits. However, very few studies have examined the underlying...

  15. [Intrauterine development, functions and diseases of male reproductive organs].

    PubMed

    Jakobovits, Akos; Jakobovits, Antal

    2010-09-26

    This article discusses the role of the central nervous system and testosterone hormone and its derivatives in the intrauterine development of male reproductive organs. The characteristics that define male personality first emerge in fetal stage of human development. Thereafter they continue to evolve during childhood. They become increasingly apparent after puberty and then remain prevalent throughout the individual's life time. The cited process affects both male phenotype and masculine behavior. Testosterone and its derivatives control the development of male reproductive organs. Their absence leads to predominance of female sexual characteristics even in the presence of a male chromosome pattern. The clinical entity of testicular feminization is a typical example for this phenomenon. The presented study pays special attention to those abnormalities of male reproductive organs that are identifiable by ultrasound during the fetal period. Most of these anomalies cannot be treated effectively before birth. Those conditions that are also incurable in extra uterine life, may serve as indication for pregnancy termination if they can be detected by ultrasound examination in early gestation. PMID:20840913

  16. H2AX Is Required for Chromatin Remodeling and Inactivation of Sex Chromosomes in Male Mouse Meiosis

    Microsoft Academic Search

    Oscar Fernandez-Capetillo; Shantha K. Mahadevaiah; Arkady Celeste; Peter J. Romanienko; R. Daniel Camerini-Otero; William M. Bonner; Katia Manova; Paul Burgoyne; André Nussenzweig

    2003-01-01

    During meiotic prophase in male mammals, the X and Y chromosomes condense to form a macrochromatin body, termed the sex, or XY, body, within which X- and Y-linked genes are transcriptionally repressed. The molecular basis and biological function of both sex body formation and meiotic sex chromosome inactivation (MSCI) are unknown. A phosphorylated form of H2AX, a histone H2A variant

  17. Sex steroid hormones modulate responses to social challenge and opportunity in males of the monogamous convict cichlid, Amatitliana

    E-print Network

    Hofmann, Hans A.

    Sex steroid hormones modulate responses to social challenge and opportunity in males s t r a c t Steroid hormones play an important role in modulating behavioral responses to various social a repeated measure design to create behavioral profiles and explore how sex steroid hormones respond

  18. Sex differences in recovery from PTSD in male and female interpersonal assault survivors.

    PubMed

    Galovski, Tara E; Blain, Leah M; Chappuis, Courtney; Fletcher, Thomas

    2013-06-01

    Men and women differ in exposure to trauma and the development of posttraumatic stress disorder (PTSD); however, research regarding sex differences in recovery from PTSD has been sparse. This study evaluated the treatment response trajectory for 69 male and female interpersonal assault survivors, using a modified Cognitive Processing Therapy (CPT) protocol that allowed survivors to receive up to18 sessions of CPT, with treatment end determined by therapy progress. Few sex differences were observed in trauma history, baseline PTSD and depressive severity, Axis I comorbidity, anger, guilt and dissociation. Women did report more sexual assault in adulthood and elevated baseline guilt cognitions, whereas men reported more baseline anger directed inward. Attrition and total number of sessions did not differ by sex. Over the course of treatment and follow-up, men and women demonstrated similar rates of change in PTSD and depressive symptoms. However, medium effect sizes on both of these primary outcomes at the 3-month follow-up assessment favored women. Several differences in the slope of change emerged on secondary outcomes such that women evidenced more rapid gains on global guilt, guilt cognitions, anger/irritability, and dissociation. Results suggest that male survivors may warrant additional attention to address these important clinical correlates. PMID:23510841

  19. Sex Differences in Spatial Memory in Brown-Headed Cowbirds: Males Outperform Females on a Touchscreen Task

    PubMed Central

    Guigueno, Mélanie F.; MacDougall-Shackleton, Scott A.; Sherry, David F.

    2015-01-01

    Spatial cognition in females and males can differ in species in which there are sex-specific patterns in the use of space. Brown-headed cowbirds are brood parasites that show a reversal of sex-typical space use often seen in mammals. Female cowbirds, search for, revisit and parasitize hosts nests, have a larger hippocampus than males and have better memory than males for a rewarded location in an open spatial environment. In the current study, we tested female and male cowbirds in breeding and non-breeding conditions on a touchscreen delayed-match-to-sample task using both spatial and colour stimuli. Our goal was to determine whether sex differences in spatial memory in cowbirds generalizes to all spatial tasks or is task-dependant. Both sexes performed better on the spatial than on the colour touchscreen task. On the spatial task, breeding males outperformed breeding females. On the colour task, females and males did not differ, but females performed better in breeding condition than in non-breeding condition. Although female cowbirds were observed to outperform males on a previous larger-scale spatial task, males performed better than females on a task testing spatial memory in the cowbirds’ immediate visual field. Spatial abilities in cowbirds can favour males or females depending on the type of spatial task, as has been observed in mammals, including humans. PMID:26083573

  20. Dgcr8 and Dicer are essential for sex chromosome integrity during meiosis in males.

    PubMed

    Modzelewski, Andrew J; Hilz, Stephanie; Crate, Elizabeth A; Schweidenback, Caterina T H; Fogarty, Elizabeth A; Grenier, Jennifer K; Freire, Raimundo; Cohen, Paula E; Grimson, Andrew

    2015-06-15

    Small RNAs play crucial roles in regulating gene expression during mammalian meiosis. To investigate the function of microRNAs (miRNAs) and small interfering RNAs (siRNAs) during meiosis in males, we generated germ-cell-specific conditional deletions of Dgcr8 and Dicer in mice. Analysis of spermatocytes from both conditional knockout lines revealed that there were frequent chromosomal fusions during meiosis, always involving one or both sex chromosomes. RNA sequencing indicates upregulation of Atm in spermatocytes from miRNA-deficient mice, and immunofluorescence imaging demonstrates an increased abundance of activated ATM kinase and mislocalization of phosphorylated MDC1, an ATM phosphorylation substrate. The Atm 3'UTR contains many potential microRNA target sites, and, notably, target sites for several miRNAs depleted in both conditional knockout mice were highly effective at promoting repression. RNF8, a telomere-associated protein whose localization is controlled by the MDC1-ATM kinase cascade, normally associates with the sex chromosomes during pachytene, but in both conditional knockouts redistributed to the autosomes. Taken together, these results suggest that Atm dysregulation in microRNA-deficient germ lines contributes to the redistribution of proteins involved in chromosomal stability from the sex chromosomes to the autosomes, resulting in sex chromosome fusions during meiotic prophase I. PMID:25934699

  1. Dgcr8 and Dicer are essential for sex chromosome integrity during meiosis in males

    PubMed Central

    Modzelewski, Andrew J.; Hilz, Stephanie; Crate, Elizabeth A.; Schweidenback, Caterina T. H.; Fogarty, Elizabeth A.; Grenier, Jennifer K.; Freire, Raimundo; Cohen, Paula E.; Grimson, Andrew

    2015-01-01

    ABSTRACT Small RNAs play crucial roles in regulating gene expression during mammalian meiosis. To investigate the function of microRNAs (miRNAs) and small interfering RNAs (siRNAs) during meiosis in males, we generated germ-cell-specific conditional deletions of Dgcr8 and Dicer in mice. Analysis of spermatocytes from both conditional knockout lines revealed that there were frequent chromosomal fusions during meiosis, always involving one or both sex chromosomes. RNA sequencing indicates upregulation of Atm in spermatocytes from miRNA-deficient mice, and immunofluorescence imaging demonstrates an increased abundance of activated ATM kinase and mislocalization of phosphorylated MDC1, an ATM phosphorylation substrate. The Atm 3?UTR contains many potential microRNA target sites, and, notably, target sites for several miRNAs depleted in both conditional knockout mice were highly effective at promoting repression. RNF8, a telomere-associated protein whose localization is controlled by the MDC1–ATM kinase cascade, normally associates with the sex chromosomes during pachytene, but in both conditional knockouts redistributed to the autosomes. Taken together, these results suggest that Atm dysregulation in microRNA-deficient germ lines contributes to the redistribution of proteins involved in chromosomal stability from the sex chromosomes to the autosomes, resulting in sex chromosome fusions during meiotic prophase I. PMID:25934699

  2. Diversity of commercial sex among men and male-born trans people in three Peruvian cities

    PubMed Central

    Zúñiga, Mario; Zunt, Joseph; Mejía, Carolina; Montano, Silvia; Sánchez, Jorge L.

    2011-01-01

    In Peru, commercial sex involving men and male-born travestis, transgenders and transsexuals (CSMT) is usually represented as a dangerous practice carried out on the streets by people experiencing economic hardship and social exclusion. However, in reality little is known about the complexities of this practice in Peru. This paper presents findings from an ethnographic study of the characteristics, patterns and socio-cultural aspects of CSMT in three Peruvian cities. The study included participant observation in sex work venues and interviews with 42 sex workers and 25 key informants. We found that CSMT in Peru takes many forms (some not previously described in the country) and is practised in different places by people from various socioeconomic levels. In many cases, the practice appears linked to ideals of social mobility, migratory experiences and other economic activities. In addition, the increasing use of the internet and mobile phones has changed patterns of sex work in Peru. We review the implications of these findings for future research and public health interventions. PMID:21936651

  3. Randomised controlled trial of alternative male and female condom promotion strategies targeting sex workers in Madagascar

    PubMed Central

    Hoke, Theresa H; Feldblum, Paul J; Van Damme, Kathleen; Nasution, Marlina D; Grey, Thomas W; Wong, Emelita L; Ralimamonjy, Louisette; Raharimalala, Leonardine; Rasamindrakotroka, Andry

    2007-01-01

    Objectives To assess whether individual clinic?based counselling as a supplement to peer education for male and female condom promotion leads to greater use of protection and lower STI prevalence among sex workers in Madagascar already exposed to intensive male condom promotion. Methods In two public dispensaries in Madagascar, a total of 901 sex workers were randomly allocated between two alternative male and female condom promotion interventions: peer education only, or peer education supplemented with individual clinic?based counselling. Participants were followed for 12?months. Every 2?months they made clinic visits, where they were interviewed on condom use. Peer educators counselled all participants on condom use as they accompanied their assigned participants to study visits. Participants assigned to receive the supplemental intervention were counselled by a trained clinician following study interviews. Participants were tested and treated for chlamydia, gonorrhoea and trichomoniasis every 6?months. We used logistic regression to assess whether the more intensive intervention was associated with reduced STI prevalence. Use of protection with clients and non?paying partners was assessed by study arm, site, and visit. Results There was no statistically significant association between study arm and aggregated STI prevalence. No substantial differences in levels of reported protection were noted between study groups. Conclusions This study found little evidence for gains from more thorough clinical counselling on male and female condom use. These findings suggest that less clinically intensive interventions such as peer education could be suitable for male and female condom promotion in populations already exposed to barrier method promotion. PMID:17591662

  4. Induction of Female-to-Male Sex Change in Adult Zebrafish by Aromatase Inhibitor Treatment

    NASA Astrophysics Data System (ADS)

    Takatsu, Kanae; Miyaoku, Kaori; Roy, Shimi Rani; Murono, Yuki; Sago, Tomohiro; Itagaki, Hideyuki; Nakamura, Masaru; Tokumoto, Toshinobu

    2013-12-01

    This study investigated whether undifferentiated germ and/or somatic stem cells remain in the differentiated ovary of a species that does not undergo sex changes under natural conditions and retain their sexual plasticity. The effect of aromatase inhibitor (AI)-treatment on sexually mature female zebrafish was examined. A 5-month AI treatment caused retraction of the ovaries after which testes-like organs appeared, and cyst structures filled with spermatozoa-like cells were observed in sections of these tissues. Electron microscopic observations revealed that these cells appeared as large sperm heads without tails. Sperm formation was re-examined after changing the diet to an AI-free food. A large number of normal sperm were obtained after eight weeks, and no formation of ovarian tissue was observed. Artificial fertilization using sperm from the sex-changed females was successful. These results demonstrated that sex plasticity remains in the mature ovaries of this species.

  5. Induction of female-to-male sex change in adult zebrafish by aromatase inhibitor treatment.

    PubMed

    Takatsu, Kanae; Miyaoku, Kaori; Roy, Shimi Rani; Murono, Yuki; Sago, Tomohiro; Itagaki, Hideyuki; Nakamura, Masaru; Tokumoto, Toshinobu

    2013-01-01

    This study investigated whether undifferentiated germ and/or somatic stem cells remain in the differentiated ovary of a species that does not undergo sex changes under natural conditions and retain their sexual plasticity. The effect of aromatase inhibitor (AI)-treatment on sexually mature female zebrafish was examined. A 5-month AI treatment caused retraction of the ovaries after which testes-like organs appeared, and cyst structures filled with spermatozoa-like cells were observed in sections of these tissues. Electron microscopic observations revealed that these cells appeared as large sperm heads without tails. Sperm formation was re-examined after changing the diet to an AI-free food. A large number of normal sperm were obtained after eight weeks, and no formation of ovarian tissue was observed. Artificial fertilization using sperm from the sex-changed females was successful. These results demonstrated that sex plasticity remains in the mature ovaries of this species. PMID:24292399

  6. Modeling the suppression of sea lamprey populations by use of the male sex pheromone

    USGS Publications Warehouse

    Klassen, Waldemar; Adams, Jean V.; Twohey, Michael B.

    2005-01-01

    The suppression of sea lamprey populations, Petromyzon marinus (Linnaeus), was modeled using four different applications of the male sex pheromone: (1) pheromone-baited traps that remove females from the spawning population, (2) pheromone-baited decoys that exhaust females before they are able to spawn, (3) pheromone-enhanced sterile males that increase the proportion of non-fertile matings, and (4) camouflaging of the pheromone emitted by calling males to make it difficult for females to find a mate. The models indicated that thousands of traps or hundreds of thousands of decoys would be required to suppress a population of 100,000 animals. The potential efficacy of pheromone camouflages is largely unknown, and additional research is required to estimate how much pheromone is needed to camouflage the pheromone plumes of calling males. Pheromone-enhanced sterile males appear to be a promising application in the Great Lakes. Using this technique for three generations each of ca. 7 years duration could reduce sea lamprey populations by 90% for Lakes Huron and Ontario and by 98% for Lake Michigan, based on current trapping operations that capture 20 to 30% of the population each year.

  7. Relationship characteristics and HIV transmission risk in same-sex male couples in HIV serodiscordant relationships.

    PubMed

    Starks, Tyrel J; Gamarel, Kristi E; Johnson, Mallory O

    2014-01-01

    Unprotected anal intercourse (UAI) remains a main risk factor for HIV among men who have sex with men (MSM) and this is of particular concern for partners of HIV serodiscordant status. However, HIV transmission risk has been demonstrated to vary by the sexual position adopted among partners. Guided by interdependence theory, this study examined how relational factors were differentially associated with risk taking (HIV-positive/insertive and HIV-negative/receptive) and strategic positioning (HIV-positive/receptive and HIV-negative/insertive) UAI within serodiscordant same-sex male couples. HIV-positive men and their HIV-negative partners (n couples = 91; n individuals = 182) simultaneously but independently completed computerized questionnaires and HIV-positive men had blood drawn for viral load. A minority of couples (30 %) engaged in risk taking and/or strategic positioning unprotected anal sex. Results of multinomial logistic regression indicated that HIV-negative partners' levels of relationship commitment were positively associated with the odds of engaging in strategic positioning sexual behaviors. For HIV-negative partners, reports of relationship intimacy, and sexual satisfaction were negatively associated with odds of reporting risk taking behavior. In contrast, HIV-positive partners' reported sexual satisfaction was positively associated with odds of engaging in risk taking behavior. Findings suggested that aspects of relational quality may be differentially associated with sexual decision making for same-sex male couples in serodiscordant relationships. Study findings lend support for the incorporation of discussions of HIV risk reduction strategies, enhancing communication between partners, and support for general relationship functioning in HIV care. PMID:24243004

  8. Relationship Characteristics and HIV Transmission Risk in Same-sex Male Couples in HIV Serodiscordant Relationships

    PubMed Central

    Starks, Tyrel J.; Gamarel, Kristi E.; Johnson, Mallory O.

    2014-01-01

    Unprotected anal intercourse (UAI) remains a main risk factor for HIV among men who have sex with men (MSM) and this is of particular concern for partners of HIV serodiscordant status. However, HIV transmission risk has been demonstrated to vary by the sexual position adopted among partners. Guided by interdependence theory, this study examined how relational factors were differentially associated with risk taking (HIV-positive/insertive and HIV-negative/receptive) and strategic positioning (HIV-positive/receptive and HIV-negative/insertive) UAI withinserodiscordant same-sex male couples. HIV-positive men and their HIV-negative partners (ncouples=91; nindividuals=182) simultaneously but independently completed computerized questionnaires and HIV-positive men had blood drawn for viral load.A minority of couples (30%) engaged in risk taking and/or strategicpositioning unprotected anal sex. Results of multinomial logistic regressionindicated that HIV-negative partners’ levels of relationship commitment were positively associated with the odds of engaging in both risk taking and strategic positioning sexual behaviors. For HIV-negative partners, reports of relationship intimacy, autonomy, and sexual satisfaction were negatively associated with odds of reporting risk taking behavior. In contrast, HIV-positive partners’reported sexual satisfaction was positively associated with odds of engaging in risk taking behavior. Findings suggested that aspects of relational quality may be differentially associated with sexual decision making for same-sex male couples in serodiscordant relationships. Study findings lend support for the incorporation ofdiscussions of HIV risk reduction strategies, enhancing communication between partners, and support for general relationship functioning in HIV care. PMID:24243004

  9. Plant odorants interfere with detection of sex pheromone signals by male Heliothis virescens

    PubMed Central

    Pregitzer, Pablo; Schubert, Marco; Breer, Heinz; Hansson, Bill S.; Sachse, Silke; Krieger, Jürgen

    2012-01-01

    In many insects, mate finding relies on female-released sex pheromones, which have to be deciphered by the male olfactory system within an odorous background of plant volatiles present in the environment of a calling female. With respect to pheromone-mediated mate localization, plant odorants may be neutral, favorable, or disturbing. Here we examined the impact of plant odorants on detection and coding of the major sex pheromone component, (Z)-11-hexadecenal (Z11-16:Ald) in the noctuid moth Heliothis virescens. By in vivo imaging the activity in the male antennal lobe (AL), we monitored the interference at the level of olfactory sensory neurons (OSN) to illuminate mixture interactions. The results show that stimulating the male antenna with Z11-16:Ald and distinct plant-related odorants simultaneously suppressed pheromone-evoked activity in the region of the macroglomerular complex (MGC), where Z11-16:Ald-specific OSNs terminate. Based on our previous findings that antennal detection of Z11-16:Ald involves an interplay of the pheromone binding protein (PBP) HvirPBP2 and the pheromone receptor (PR) HR13, we asked if the plant odorants may interfere with any of the elements involved in pheromone detection. Using a competitive fluorescence binding assay, we found that the plant odorants neither bind to HvirPBP2 nor affect the binding of Z11-16:Ald to the protein. However, imaging experiments analyzing a cell line that expressed the receptor HR13 revealed that plant odorants significantly inhibited the Z11-16:Ald-evoked calcium responses. Together the results indicate that plant odorants can interfere with the signaling process of the major sex pheromone component at the receptor level. Consequently, it can be assumed that plant odorants in the environment may reduce the firing activity of pheromone-specific OSNs in H. virescens and thus affect mate localization. PMID:23060749

  10. HIV, syphilis, hepatitis C and risk behaviours among commercial sex male clients in Sichuan province, China

    PubMed Central

    Yang, Cui; Latkin, Carl; Luan, Rongsheng; Wang, Cunling; Nelson, Kenrad

    2015-01-01

    Objectives Commercial sex male clients (CSMC) are at risk of sexually transmitted infections (STI) including HIV. This study reports the prevalence of HIV, syphilis and hepatitis C virus (HCV), a history of STI and HIV-related risk behaviours in a sample of 600 CSMC in three urban areas in Sichuan province, China. The risk factors for prevalent syphilis infection are also examined. Methods A cross-sectional survey was conducted with 600 CSMC in Sichuan province, China. Finger stick blood samples were collected for HIV, syphilis and HCV tests. Risk factors for syphilis were assessed using multivariate logistic regression by accounting for variance within and between study sites. Results Western blot confirmatory test results indicated that HIV prevalence was 1.5% (n=9). 32 participants (5.3%) screened positive for syphilis and 52 (8.7%) positive for HCV. The overall prevalence of consistent condom use with female sex workers (FSW) was 30.5%. Multivariate logistic regression analyses revealed local household registration (AOR 0.35, 95% CI 0.25 to 0.50), having snorted heroin in the past 6 months (AOR 2.36, 95% CI 1.18 to 4.74), always washing genitals after having sex with FSW (AOR 3.04, 95% CI 1.10 to 9.12) and consistent condom use with FSW (AOR 0.67, 95% CI 0.46 to 0.98) were significant correlates of syphilis infection. Conclusions There is a large burden of syphilis infection coupled with high-risk sexual and substance use behaviours among male clients in Sichuan province, China. The data suggest that effective and comprehensive prevention interventions to promote condom use and reduce substance use among male clients in Sichuan province are urgently needed. PMID:20826867

  11. Homosexual threat, negative attitudes toward masturbation, sex guilt, and males' sexual and affective reactions to explicit sexual films

    Microsoft Academic Search

    Donald L. Mosher; Kevin E. OGrady

    1979-01-01

    Subjective sexual arousal and affective responses of 215 undergraduate males to films of masturbatory, homosexual, and heterosexual behavior were studied as a function of personality differences in negative attitudes toward masturbation, homosexual threat, and sex guilt. The film of heterosexual behavior elicited more subjective sexual arousal and less disgust, anger, shame, depression, and guilt than did the films of male

  12. Correlates of Self-efficacy for Condom Use among Male Clients of Female Sex Workers in Tijuana, Mexico

    PubMed Central

    Volkmann, Tyson; Wagner, Karla D.; Strathdee, Steffanie A.; Semple, Shirley J.; Ompad, Danielle C.; Chavarin, Claudia V.; Patterson, Thomas L.

    2013-01-01

    Male clients of female sex workers (FSWs) in Tijuana, Mexico engage in high levels of unprotected sex. While behavioral change theories posit that self-efficacy predicts condom use, correlates of self-efficacy for condom use remain largely unstudied. We examined these correlates among male clients of FSWs in Tijuana. Eligible male clients were at least 18 years of age, HIV-negative, lived in Tijuana or San Diego, reported unprotected sex with a Tijuana FSW at least once in the past four months, and agreed to be treated for sexually transmitted infections (STIs). Participants completed an interviewer-administered questionnaire including demographics, substance use, psychosocial and psychosexual characteristics (e.g., outcome expectancies for negotiation of safer sex, social support, and sexual sensation seeking), and sexual behaviors. Participants also underwent HIV/STI testing. A stepwise hierarchical multiple regression analysis identified correlates of self-efficacy for condom use. Of 393 male clients, median age was 37 years. Participants were mostly Spanish-speaking and employed. Factors independently associated with higher self-efficacy for condom use were higher positive outcome expectancies for negotiation of safer sex, lower sexual sensation seeking scores, and higher social support scores. Both psychosocial and psychosexual factors may influence self-efficacy for condom use among male clients of FSWs. These factors represent central constructs in sociocognitive models that explain behavioral change and could be intervention targets for improving self-efficacy for condom use and, ultimately, safer sex behavior. PMID:23842786

  13. The syndemic condition of psychosocial problems and HIV risk among male sex workers in Ho Chi Minh City, Vietnam.

    PubMed

    Biello, Katie B; Colby, Donn; Closson, Elizabeth; Mimiaga, Matthew J

    2014-07-01

    In Vietnam, the co-occurrence (i.e., "syndemic") of psychosocial factors (e.g., depression and substance use) may disproportionately burden male sex workers and increase their HIV risk. A comprehensive survey was conducted among 300 male sex workers in Ho Chi Minh City, Vietnam in 2010. We performed logistic regression to examine the association between the syndemic variable-a count score of the number of five psychosocial conditions endorsed-and unprotected anal sex (UAS) in the past. One-third of participants reported any UAS, and 42 % reported ?2 psychosocial health problems. In multivariable models, experiencing ?4 psychosocial health problems was significantly associated with UAS. Every unit increase in number of psychosocial health problems was associated with a 25-30 % increase in odds of UAS. Understanding the syndemic condition and its association with HIV risk among male sex workers in Vietnam may lead to the development of more effective, comprehensive interventions. PMID:24081899

  14. The Syndemic Condition of Psychosocial Problems and HIV Risk Among Male Sex Workers in Ho Chi Minh City, Vietnam

    PubMed Central

    Biello, Katie; Colby, Donn; Closson, Elizabeth; Mimiaga, Matthew J.

    2015-01-01

    In Vietnam, the co-occurrence (i.e., “syndemic”) of psychosocial factors (e.g., depression and substance use) may disproportionately burden male sex workers and increase their HIV risk. A comprehensive survey was conducted among 300 male sex workers in Ho Chi Minh City, Vietnam in 2010. We performed logistic regression to examine the association between the syndemic variable – a count score of the number of 5 psychosocial conditions endorsed – and unprotected anal sex (UAS) in the past. One-third of participants reported any UAS, and 42% reported ? 2 psychosocial health problems. In multivariable models, experiencing ? 4 psychosocial health problems was significantly associated with UAS. Every unit increase in number of psychosocial health problems was associated with a 25%–30% increase in odds of UAS. Understanding the syndemic condition and its association with HIV risk among male sex workers in Vietnam may lead to the development of more effective, comprehensive interventions. PMID:24081899

  15. Androgenic control of male-typical behavior, morphology and sex recognition is independent of the mode of sex determination: A case study on Lichtenfelder's gecko (Eublepharidae: Goniurosaurus lichtenfelderi).

    PubMed

    Golinski, Alison; Kubi?ka, Lukáš; John-Alder, Henry; Kratochvíl, Lukáš

    2015-06-01

    Previous work on lizards has shown that many sexually dimorphic traits depend on testosterone (T), but the details of this control can vary among species. Here, we tested the role of T on the expression of morphological, physiological, and behavioral traits in Lichtenfelder's gecko (Goniurosaurus lichtenfelderi), from the lizard family Eublepharidae notable for interspecific variation in sexually dimorphic traits and the mode of sex determination. Experiments included three groups of males (intact control, surgically castrated, castrated with T replacement) and two groups of females (intact control, T supplemented). In males, castration caused reductions in 1) the size of hemipenes, 2) offensive aggression, 3) male sexual behavior in a neutral arena, 4) activity of precloacal glands, and 5) loss of male chemical cues for sex recognition. These reductions were not observed in castrated males with T replacement. Interestingly, castrated males performed sexual behavior in their home cages, which shows that the effect of T depends on the environmental context. Notably, tail vibration, previously reported as a courtship behavior in other eublepharids, is displayed by males of G. lichtenfelderi during interactions with conspecifics of both sexes, suggesting an evolutionary shift in the meaning of this signal. In females, T induced growth of hemipenes and male-typical courtship but did not induce precloacal pore activity, aggression, or mounting. In comparison to previous reports on Eublepharis macularius, our results indicate that effects of T do not depend on the mode of sex determination. Further, our results extend our understanding of the complexity of control of male traits and illustrate how lability in the effects of T can be a general mechanism causing evolutionary changes in the components of suites of functionally correlated traits. PMID:25967849

  16. Sex differences in impaling behaviour of Great Grey Shrike Lanius excubitor: do males have better impaling skills than females?

    PubMed

    Antczak, Marcin; Hromada, Martin; Tryjanowski, Piotr

    2012-09-01

    Prey impaling in shrikes Laniidae is considered to be a feeding adaptation to dismember and consume large prey and is unique among food-storing animals. However, other exaptations of this behaviour were recorded, including signals in mate choice, where cache size is a sign of male quality. Thus, due to a strong sexual selection, male and female birds might differ in their behavioural patterns of impaling behaviour. We examined sex differences in impaling behaviour of the Great Grey Shrike Lanius excubitor - one of the species where caches are known to be sexual signals. Data were collected in western Poland during breeding seasons in the years 2006-2010. In the studied population, we recorded several sex-specific differences in impaling behaviour. Males impaled prey, invertebrates as well as vertebrates, faster and with fewer attempts per impaling event than females. Sexes differed in the location of impaled prey; males selected more visible places, especially during the mating and courtship phase, whereas females impaled prey in concealed locations. Males also had slightly better impaling success compared to females. We suggest that sex differences in impaling behaviour may be due to different uses of impaled prey, and the better impaling skills of males may be the result of better experience in impaling which is forced by sexual selection in this species. We also discuss other factors which might trigger sex-specific differences in food caching by shrikes. PMID:22659619

  17. Sex and Condom Use in a Large Jail Unit for Men Who Have Sex with Men (MSM) and Male-to-Female Transgenders

    PubMed Central

    Harawa, Nina T.; Sweat, Jeffery; George, Sheba; Sylla, Mary

    2013-01-01

    Few data are available on factors contributing to sexual activity and condom use in custody settings, particularly among self-identified sexual minority prisoners. To address this gap, we undertook a study of sexual behavior and condom use of 101 randomly-selected men who have sex with men (MSM) and male-to-female transgender inmates in a segregated Los Angeles jail unit that has weekly condom access. Most survey participants (53%) reported anal sex during custody. Although 65% of these reported using condoms, 75% also reported having sex without condoms. Qualitative interviews (n=17) indicate a wide range of reasons for participating in protected and unprotected sex during custody, the use of cues within the custody environment to assess potential partners’ HIV status, and support for increased condom availability. Findings also indicate that high-risk sex occurs frequently in this unit and that condom distribution likely prevents a substantial amount of related HIV/STD risk. PMID:20693745

  18. Breeding periodicity for male sea turtles, operational sex ratios, and implications in the face of climate change.

    PubMed

    Hays, Graeme C; Fossette, Sabrina; Katselidis, Kostas A; Schofield, Gail; Gravenor, Mike B

    2010-12-01

    Species that have temperature-dependent sex determination (TSD) often produce highly skewed offspring sex ratios contrary to long-standing theoretical predictions. This ecological enigma has provoked concern that climate change may induce the production of single-sex generations and hence lead to population extirpation. All species of sea turtles exhibit TSD, many are already endangered, and most already produce sex ratios skewed to the sex produced at warmer temperatures (females). We tracked male loggerhead turtles (Caretta caretta) from Zakynthos, Greece, throughout the entire interval between successive breeding seasons and identified individuals on their breeding grounds, using photoidentification, to determine breeding periodicity and operational sex ratios. Males returned to breed at least twice as frequently as females. We estimated that the hatchling sex ratio of 70:30 female to male for this rookery will translate into an overall operational sex ratio (OSR) (i.e., ratio of total number of males vs females breeding each year) of close to 50:50 female to male. We followed three male turtles for between 10 and 12 months during which time they all traveled back to the breeding grounds. Flipper tagging revealed the proportion of females returning to nest after intervals of 1, 2, 3, and 4 years were 0.21, 0.38, 0.29, and 0.12, respectively (mean interval 2.3 years). A further nine male turtles were tracked for short periods to determine their departure date from the breeding grounds. These departure dates were combined with a photoidentification data set of 165 individuals identified on in-water transect surveys at the start of the breeding season to develop a statistical model of the population dynamics. This model produced a maximum likelihood estimate that males visit the breeding site 2.6 times more often than females (95%CI 2.1, 3.1), which was consistent with the data from satellite tracking and flipper tagging. Increased frequency of male breeding will help ameliorate female-biased hatchling sex ratios. Combined with the ability of males to fertilize the eggs of many females and for females to store sperm to fertilize many clutches, our results imply that effects of climate change on the viability of sea turtle populations are likely to be less acute than previously suspected. PMID:20497201

  19. Prevalence of Consensual Male–Male Sex and Sexual Violence, and Associations with HIV in South Africa: A Population-Based Cross-Sectional Study

    PubMed Central

    Dunkle, Kristin L.; Jewkes, Rachel K.; Murdock, Daniel W.; Sikweyiya, Yandisa; Morrell, Robert

    2013-01-01

    Background In sub-Saharan Africa the population prevalence of men who have sex with men (MSM) is unknown, as is the population prevalence of male-on-male sexual violence, and whether male-on-male sexual violence may relate to HIV risk. This paper describes lifetime prevalence of consensual male–male sexual behavior and male-on-male sexual violence (victimization and perpetration) in two South African provinces, socio-demographic factors associated with these experiences, and associations with HIV serostatus. Methods and Findings In a cross-sectional study conducted in 2008, men aged 18–49 y from randomly selected households in the Eastern Cape and KwaZulu-Natal provinces provided anonymous survey data and dried blood spots for HIV serostatus assessment. Interviews were completed in 1,737 of 2,298 (75.6%) of enumerated and eligible households. From these households, 1,705 men (97.1%) provided data on lifetime history of same-sex experiences, and 1,220 (70.2%) also provided dried blood spots for HIV testing. 5.4% (n?=?92) of participants reported a lifetime history of any consensual sexual activity with another man; 9.6% (n?=?164) reported any sexual victimization by a man, and 3.0% (n?=?51) reported perpetrating sexual violence against another man. 85.0% (n?=?79) of men with a history of consensual sex with men reported having a current female partner, and 27.7% (n?=?26) reported having a current male partner. Of the latter, 80.6% (n?=?21/26) also reported having a female partner. Men reporting a history of consensual male–male sexual behavior are more likely to have been a victim of male-on-male sexual violence (adjusted odds ratio [aOR]?=?7.24; 95% CI 4.26–12.3), and to have perpetrated sexual violence against another man (aOR?=?3.10; 95% CI 1.22–7.90). Men reporting consensual oral/anal sex with a man were more likely to be HIV+ than men with no such history (aOR?=?3.11; 95% CI 1.24–7.80). Men who had raped a man were more likely to be HIV+ than non-perpetrators (aOR?=?3.58; 95% CI 1.17–10.9). Conclusions In this sample, one in 20 men (5.4%) reported lifetime consensual sexual contact with a man, while about one in ten (9.6%) reported experience of male-on-male sexual violence victimization. Men who reported having had sex with men were more likely to be HIV+, as were men who reported perpetrating sexual violence towards other men. Whilst there was no direct measure of male–female concurrency (having overlapping sexual relationships with men and women), the data suggest that this may have been common. These findings suggest that HIV prevention messages regarding male–male sex in South Africa should be mainstreamed with prevention messages for the general population, and sexual health interventions and HIV prevention interventions for South African men should explicitly address male-on-male sexual violence. Please see later in the article for the Editors' Summary PMID:23853554

  20. Novel sex-dependent differentially methylated regions are demethylated in adult male mouse livers.

    PubMed

    Ito, Shuhei; Hirabayashi, Keiji; Moriishi, Kohji; Matsui, Yasuhisa; Moriya, Kyoji; Koike, Kazuhiko; Matsuura, Yoshiharu; Shiota, Kunio; Yagi, Shintaro

    2015-07-10

    In mammalian livers, sexual dimorphisms are observed in tissue-specific functions and diseases such as hepatocellular carcinoma. We identified sex-dependent differentially methylated regions (S-DMRs) which had been previously been characterized as growth hormone- STAT5 dependent. In this study, we performed genome-wide screening and identified ten additional hypomethylated S-DMR gene regions in male livers. Of these S-DMRs, Uggt2 and Sarnp were hypomethylated in both male and female livers compared to brain and embryonic stem (ES) cells. Similarly, Adam2, Uggt2, and Scp2 were hypomethylated in female embryonic germ (EG) cells and not in male EG cells, indicating that these S-DMRs are liver-specific male hypo-S-DMRs. Interestingly, the five S-DMRs were free from STAT5 chromatin immunoprecipitation (ChIP) signals, suggesting that S-DMRs are independent of the growth hormone-STAT5-pathway. Instead, the DNA methylation statuses of the S-DMRs of Adam2, Snx29, Uggt2, Sarnp, and Rnpc3 genes were under the control of testosterone. Importantly, the hypomethylated S-DMRs of the Adam2 and Snx29 regions showed chromatin decondensation. Epigenetic factors could be responsible for the sexual dimorphisms in DNA methylation status and chromatin structure, as the expression of Dnmt1, Dnmt3b, and Tet2 genes was lower in male mice compared to female mice and TET2 expression recovered following orchidectomy by testosterone treatment. In conclusion, we identified novel male-specific hypomethylated S-DMRs that contribute to chromatin decondensation in the liver. S-DMRs were tissue-specific and the hypomethylation is testosterone-dependent. PMID:25960295

  1. HIV prevalence and risk behaviors among male clients of female sex workers in Yunnan, China

    PubMed Central

    Jin, Xia; Smith, Kumi; Chen, Ray Y.; Ding, Guowei; Yao, Yan; Wang, Haibo; Qian, Han-Zhu; Chang, Dongfang; Wang, Guixiang; Wang, Ning

    2009-01-01

    Objectives To assess the prevalence and risk factors of HIV among male clients of female sex workers in China. Methods Convenience sampling methods were used to recruit 315 clients using FSW-client and client-client networks. Subjects provided information on socio-demographic characteristics and sexual and drug behavior patterns. Blood samples were collected for HIV testing and urine samples for opiate testing. Results Overall HIV prevalence was 6.0%; among drug users it was 30.8%. 33.7% of respondents reported that they always use condoms in commercial sex and 63.5% that they used a condom in the last commercial sex episode. Drug use (OR: 6.1; 95% CI: 1.7–21.4) and lack of a regular sexual partner (OR: 6.3; 95% CI: 1.8–21.9) were significantly associated with HIV infection. Conclusions Clients of FSWs serve as potential bridges for HIV transmission from the high-risk FSWs to the low-risk general population, making them a key target for intervention. High HIV prevalence rates among clients in Kaiyuan is particularly alarming given their risk behavior patterns including high rates of partner exchange, low condom use rates, and drug using behaviors. Innovative interventions are needed to reduce the risk of HIV among clients and reduce the bridge of transmission to the general population. PMID:19730110

  2. Biased sex ratio and low population density increase male mating success in the bug Nysius huttoni (Heteroptera: Lygaeidae)

    NASA Astrophysics Data System (ADS)

    Wang, Qiao; He, Xiong Zhao; Yang, Linghuan; Hedderley, Duncan; Davis, Lorraine K.

    2009-01-01

    Demographic factors such as operational sex ratio (OSR) and local population density (LPD) are temporally and spatially dynamic in the natural environment but the influence of these variables on male mating success and the mechanisms behind it are still poorly understood and highly controversial. Here, we manipulated the OSR and LPD of a seed bug, Nysius huttoni, and carried out a series of mating trials to test how these variables affected male mating success. The two demographic factors had no significant interactions, suggesting that they affect male mating success independently in N. huttoni. In this species male mating success was significantly higher in both male- and female-biased OSR than in even OSR. It is suggested that, in male-biased OSR, the increased intensity of competition and interference does not result in lower male mating success; rather, males may make more effort in courting and females may have more chance to encounter better males, resulting in higher male mating success. In female-biased OSR, females may become less choosy and less likely to reject male mating attempt, leading to the higher male mating success. Lower male mating success in N. huttoni in high LPD may be due to increased interference between males and/or delayed female receptiveness for mating. OSR had a stronger effect on male mating success than LPD in N. huttoni, suggesting that OSR and LPD affect mating success in different ways and intensities.

  3. Sex-biased gene expression on the avian Z chromosome: highly expressed genes show higher male-biased expression.

    PubMed

    Naurin, Sara; Hasselquist, Dennis; Bensch, Staffan; Hansson, Bengt

    2012-01-01

    Dosage compensation, the process whereby expression of sex-linked genes remains similar between sexes (despite heterogamety) and balanced with autosomal expression, was long believed to be essential. However, recent research has shown that several lineages, including birds, butterflies, monotremes and sticklebacks, lack chromosome-wide dosage compensation mechanisms and do not completely balance the expression of sex-linked and autosomal genes. To obtain further understanding of avian sex-biased gene expression, we studied Z-linked gene expression in the brain of two songbirds of different genera (zebra finch, Taeniopygia guttata, and common whitethroat, Sylvia communis) using microarray technology. In both species, the male-bias in gene expression was significantly higher for Z than for autosomes, although the ratio of Z-linked to autosomal expression (Z:A) was relatively close to one in both sexes (range: 0.89-1.01). Interestingly, the Z-linked male-bias in gene expression increased with expression level, and genes with low expression showed the lowest degree of sex-bias. These results support the view that the heterogametic females have up-regulated their single Z-linked homologues to a high extent when the W-chromosome degraded and thereby managed to largely balance their Z:A expression with the exception of highly expressed genes. The male-bias in highly expressed genes points towards male-driven selection on Z-linked loci, and this and other possible hypotheses are discussed. PMID:23056488

  4. Unprotected anal intercourse behavior and intention among male sex workers in Shenzhen serving cross-boundary male clients coming from Hong Kong, China - prevalence and associated factors.

    PubMed

    Lau, Joseph T F; Cai, Wende; Tsui, Hi Yi; Chen, Lin; Cheng, Jinquan; Lin, Chunqing; Gu, Jing; Hao, Chun

    2012-01-01

    The HIV epidemic among men who have sex with men (MSM) in China is becoming very serious. Unprotected anal intercourse (UAI) among MSM during cross-boundary commercial sex spread HIV across geographic areas. This study interviewed 186 Chinese male sex workers (MSW) in Shenzhen, China, serving cross-boundary Hong Kong male clients; 49.5% had had UAI with their Hong Kong male clients (last six months) and 24.2% intended to do so (future six months). Multivariate analyses showed that perceived efficacy of condom use for HIV prevention, perceived prevalence of HIV among Hong Kong MSM (>4%), and perceived ability to convince Hong Kong male clients to use condoms during anal sex were associated with lower likelihoods of UAI with such clients (OR = 0.04-0.09); the reverse was true for those who left the decision of condom use to their Hong Kong male clients (OR = 6.44). Perceived condom efficacy, self-efficacy in protection against HIV infection, and perceived control over condom use were associated with an intention for UAI (OR = 0.06-80.44). Adjusting for background variables, the scales representing contextual (Clients Characteristics, Substance Use, or Environmental Influences) and affective factors (Fear of Diseases) were associated with UAI (adjusted OR = 0.44-32.61). Except the Fear of Diseases scale, other scales were associated with an intention for UAI (adjusted OR = 4.59-43.32). MSW are at high risk of HIV transmission. Various factors are associated with UAI with male cross-boundary clients; these factors and the context of sex work need to be considered when designing HIV prevention programs. PMID:21745021

  5. MicroRNAs influence reproductive responses by females to male sex peptide in Drosophila melanogaster.

    PubMed

    Fricke, Claudia; Green, Darrell; Smith, Damian; Dalmay, Tamas; Chapman, Tracey

    2014-12-01

    Across taxa, female behavior and physiology change significantly following the receipt of ejaculate molecules during mating. For example, receipt of sex peptide (SP) in female Drosophila melanogaster significantly alters female receptivity, egg production, lifespan, hormone levels, immunity, sleep, and feeding patterns. These changes are underpinned by distinct tissue- and time-specific changes in diverse sets of mRNAs. However, little is yet known about the regulation of these gene expression changes, and hence the potential role of microRNAs (miRNAs), in female postmating responses. A preliminary screen of genomic responses in females to receipt of SP suggested that there were changes in the expression of several miRNAs. Here we tested directly whether females lacking four of the candidate miRNAs highlighted (miR-279, miR-317, miR-278, and miR-184) showed altered fecundity, receptivity, and lifespan responses to receipt of SP, when mated once or continually to SP null or control males. The results showed that miRNA-lacking females mated to SP null males exhibited altered receptivity, but not reproductive output, in comparison to controls. However, these effects interacted significantly with the genetic background of the miRNA-lacking females. No significant survival effects were observed in miRNA-lacking females housed continually with SP null or control males. However, continual exposure to control males that transferred SP resulted in significantly higher variation in miRNA-lacking female lifespan than did continual exposure to SP null males. The results provide the first insight into the effects and importance of miRNAs in regulating postmating responses in females. PMID:25245794

  6. Alcohol Use and Sex Risk Behaviors Among HIV-Infected Female Sex Workers (FSWs) and HIV-Infected Male Clients of FSWs in India

    PubMed Central

    Pace, Christine A.; Cheng, Debbie M.; Coleman, Sharon; Bridden, Carly; Pardesi, Manoj; Saggurti, Niranjan; Raj, Anita

    2010-01-01

    Unprotected heterosexual transactional sex plays a central role in the spread of HIV in India. Given alcohol’s association with risky sex in other populations and alcohol’s role in HIV disease progression, we investigated patterns of alcohol use in HIV-infected female sex workers (FSWs) and HIV-infected male clients of FSWs in Mumbai. Analyses identified factors associated with heavy alcohol use and evaluated the relationship between alcohol use and risky sex. We surveyed 211 female and 205 male individuals; 80/211 FSWs (38%) and 127/205 male clients (62%) drank alcohol in the last 30 days. Among females, 32 and 11% drank heavily and were alcohol-dependent, respectively; among males the respective proportions were 44 and 29%. Men’s heavy alcohol use was significantly associated with inconsistent condom use over the last year (AOR 2.40, 95% CI 1.21–4.77, P = 0.01); a comparable association was not seen in women. These findings suggest a need to address alcohol use both to avoid the medical complications of its heavy use in this population and to mitigate inconsistent condom use, the latter issue possibly requiring gender specific approaches. Such efforts to reduce drinking will be an important dimension to secondary HIV prevention in India. PMID:20544381

  7. Sex Education for Male Adolescent Sex Offenders in a Group Setting Led by General Psychiatry Residents: A Literature Review and Example in Practice

    ERIC Educational Resources Information Center

    Dwyer, R. Gregg; Boyd, Mary S.

    2009-01-01

    Male adolescents have been credited with a significant percentage of sex crimes in recent years. They are a heterogeneous population with offenses spanning the same range found among adult offenders. A lack of interpersonal social skills relevant to intimate relationships and inaccurate knowledge regarding appropriate sexual behaviors contribute…

  8. Useless Hearing in Male Emblemasoma auditrix (Diptera, Sarcophagidae) – A Case of Intralocus Sexual Conflict during Evolution of a Complex Sense Organ?

    PubMed Central

    Lakes-Harlan, Reinhard; deVries, Thomas; Stölting, Heiko; Stumpner, Andreas

    2014-01-01

    Sensory modalities typically are important for both sexes, although sex-specific functional adaptations may occur frequently. This is true for hearing as well. Consequently, distinct behavioural functions were identified for the different insect hearing systems. Here we describe a first case, where a trait of an evolutionary novelty and a highly specialized hearing organ is adaptive in only one sex. The main function of hearing of the parasitoid fly Emblemasoma auditrix is to locate the host, males of the cicada species Okanagana rimosa, by their calling song. This task is performed by female flies, which deposit larvae into the host. We show that male E. auditrix possess a hearing sense as well. The morphology of the tympanal organ of male E. auditrix is rather similar to the female ear, which is 8% broader than the male ear. In both sexes the physiological hearing threshold is tuned to 5 kHz. Behavioural tests show that males are able to orient towards the host calling song, although phonotaxis often is incomplete. However, despite extensive observations in the field and substantial knowledge of the biology of E. auditrix, no potentially adaptive function of the male auditory sense has been identified. This unique hearing system might represent an intralocus sexual conflict, as the complex sense organ and the behavioural relevant neuronal network is adaptive for only one sex. The correlated evolution of the sense organ in both sexes might impose substantial constraints on the sensory properties of the ear. Similar constraints, although hidden, might also apply to other sensory systems in which behavioural functions differ between sexes. PMID:24489872

  9. 1-Tridecene—male-produced sex pheromone of the tenebrionid beetle Parastizopus transgariepinus

    NASA Astrophysics Data System (ADS)

    Geiselhardt, Sven; Ockenfels, Peter; Peschke, Klaus

    2008-03-01

    Males of the genus Parastizopus (Coleoptera: Tenebrionidae) exhibit a special pheromone-emitting behaviour. They do a headstand, expose the aedeagus and remain in this posture for a few seconds. The pheromone emitted by P. transgariepinus was collected by solid-phase micro-extraction (100 ?m polydimethylsiloxane fibre) and identified as 1-tridecene by gas chromatography/mass spectrometry. Presumably, this compound originates from the aedeagal gland, a special feature in Parastizopus, as 1-tridecene is the main compound in the gland reservoirs (23.6 ± 3.8%), accompanied by various less volatile fatty acid esters (25.2 ± 2.0%) and hydrocarbons (51.2 ± 5.7%). 1-Tridecene is also part of the pygidial defensive secretion of both sexes, together with other 1-alkenes, monoterpene hydrocarbons and 1,4-benzoquinones, but as none of these other compounds was detected during calling, the pygidial gland could be ruled out as pheromone source. Extracts of the aedeagal gland reservoirs and the pygidial defensive secretion contained comparable amounts of 1-tridecene, 1.24 ± 0.41 and 1.88 ± 0.54 ?g/male, respectively. Chemo-orientation experiments using a servosphere showed that 1 ?g of 1-tridecene was attractive to females but not to males.

  10. Partners met via sex parties present significantly greater odds for condomless anal sex among MSM: an event-level analysis of venues where male partners are met.

    PubMed

    Grov, Christian; Rendina, H J; Ventuneac, Ana; Parsons, Jeffrey T

    2014-12-15

    One hundred forty-seven men who have sex with men completed time-line follow-back interviews about the venues where they met their male partners (n = 1180 sexual events with first-time partners, <30 days). We ran multivariate models to determine the association between venues and condomless anal sex (CAS). After adjusting for known correlates of CAS, partners met at sex parties presented significantly greater odds for CAS compared with meeting a partner at a gay bar/club (adjusted odds ratio = 0.44), online (adjusted odds ratio = 0.42), bathhouse (adjusted odds ratio = 0.35), or via "other" venues (adjusted odds ratio = 0.35), all P < 0.01. These findings highlight the need to develop innovative HIV/sexually transmitted infection prevention initiatives for men who attend sex parties. PMID:25226209

  11. Chemo-orientation of male Trogoderma variabile (Coleoptera, Dermestidae) in a simulated corridor of female sex pheromone

    Microsoft Academic Search

    Thomas R. Tobin; William J. Bell

    1986-01-01

    Chemo-orientation of male granary beetles (Trogoderma variabile) to female sex pheromone [(Z)-14-methyl-8-hexadecenal] was investigated using a locomotion compensator (Fig. 1).1.Beetles responded in less than 1 s to a puff of female sex pheromone in still air with an alert, antennae-raised posture, and local search orientation, with loops generated by a relatively constant turn bias (Fig. 2).2.In wind experiments the locomotion

  12. Differential Effects of Maternal Yolk Androgens on Male and Female Offspring: A Role for Sex-Specific Selection?

    PubMed Central

    Tschirren, Barbara

    2015-01-01

    Maternal hormones are important mediators of prenatal maternal effects in animals. Although their effects on offspring phenotype are often sex-specific, the reason why sometimes sons are more sensitive to prenatal hormone exposure and sometimes daughters is not well understood. Here I combine an experimental manipulation of yolk testosterone concentration in the egg and quantification of selection acting on yolk androgen-sensitive traits in a natural population of great tits (Parus major) with a literature review to test the hypothesis that sex-specific selection on traits affected by yolk androgens determines which sex is more sensitive to prenatal hormone exposure. An experimental increase of the testosterone content in the egg boosted the post-hatching growth of male, but not female great tit nestlings. However, I found no evidence that survival selection on body mass or size is acting differently in the two sexes. A literature review revealed that yolk androgen manipulations affect the growth of males and females differently across species. Interestingly, in studies performed in the wild a significant association between the strength and direction of sexual size dimorphism and sex-specific sensitivities to yolk androgens was observed. In studies performed in captivity, no such relationship was found. Thus, across species there is some evidence that sex-specific selection on body size influences how strongly growth trajectories of males and females are affected by maternally-derived yolk androgens. PMID:26192990

  13. Venue-Mediated Weak Ties in Multiplex HIV Transmission Risk Networks Among Drug-Using Male Sex Workers and Associates

    PubMed Central

    Wang, Peng; Ross, Michael W.; Williams, Mark L.

    2015-01-01

    Objectives. We investigated the structural characteristics of a multiplex HIV transmission risk network of drug-using male sex workers and their associates. Methods. Using a sample of 387 drug-using male sex workers and their male and female associates in Houston, Texas, we estimated an exponential random graph model to examine the venue-mediated relationships between individuals, the structural characteristics of relationships not linked to social venues, and homophily. We collected data in 2003 to 2004. The network comprised social, sexual, and drug-using relationships and affiliations with social venues. Results. Individuals affiliated with the same social venues, bars, or street intersections were more likely to have nonreciprocated (weak) ties with others. Sex workers were less likely than were other associates to have reciprocated (strong) ties to other sex workers with the same venues. Individuals tended to have reciprocated ties not linked to venues. Partner choice tended to be predicated on homophily. Conclusions. Social venues may provide a milieu for forming weak ties in HIV transmission risk networks centered on male sex workers, which may foster the efficient diffusion of prevention messages as diverse information is obtained and information redundancy is avoided. PMID:25880956

  14. B-chromosomes and male-biased sex ratio with paternal inheritance in the fairy shrimp Branchipus schaefferi (Crustacea, Anostraca).

    PubMed

    Beladjal, L; Vandekerckhove, T T M; Muyssen, B; Heyrman, J; de Caesemaeker, J; Mertens, J

    2002-05-01

    This study reports on male-biased sex ratios in west Mediterranean populations of the freshwater anostracan Branchipus schaefferi (Crustacea, Anostraca, Branchipodidae), in contrast to populations elsewhere. Crossing experiments over several generations indicate a clear paternal inheritance of the trait, possibly with a dosage effect. Various mechanisms which may underlie this phenomenon are discussed, the most plausible being the presence of one or more supernumerary ('B') chromosomes--as evidenced by karyological observations--interfering with sex determination and probably having an accumulation mechanism in male individuals. PMID:11986871

  15. Behavioural evidence of male volatile pheromones in the sex-role reversed wolf spiders Allocosa brasiliensis and Allocosa alticeps

    NASA Astrophysics Data System (ADS)

    Aisenberg, Anita; Baruffaldi, Luciana; González, Macarena

    2010-01-01

    The use of chemical signals in a sexual context is widespread in the animal kingdom. Most studies in spiders report the use of female pheromones that attract potential sexual partners. Allocosa brasiliensis and Allocosa alticeps are two burrowing wolf spiders that show sex-role reversal. Females locate male burrows and initiate courtship before males perform any detectable visual or vibratory signal. So, females of these species would be detecting chemical or mechanical cues left by males. Our objective was to explore the potential for male pheromones to play a role in mate detection in A. brasiliensis and A. alticeps. We designed two experiments. In Experiment 1, we tested the occurrence of male contact pheromones by evaluating female courtship when exposed to empty burrows constructed by males or females (control). In Experiment 2, we tested the existence of male volatile pheromones by evaluating female behaviour when exposed to artificial burrows connected to tubes containing males, females or empty tubes (control). Our results suggest the occurrence of male volatile pheromones that trigger female courtship in both Allocosa species. The sex-role reversal postulated for these wolf spiders could be driving the consequent reversal in typical pheromone-emitter and detector roles expected for spiders.

  16. Prevalence and correlates of non-disclosure of HIV serostatus to sex partners among HIV-infected female sex workers and HIV-infected male clients of female sex workers in India.

    PubMed

    Saggurti, Niranjan; Raj, Anita; Mahapatra, Bidhubhusan; Cheng, Debbie M; Coleman, Sharon; Bridden, Carly; Battala, Madhusudana; Silverman, Jay G; Pardeshi, Manoj H; Samet, Jeffrey H

    2013-01-01

    This study examines non-disclosure of HIV serostatus to sex partners among HIV-infected adults involved with transactional sex in Mumbai, India. Surveys were conducted with HIV-infected female sex workers (n = 211) and infected male clients (n = 205) regarding HIV knowledge, awareness of sex partners' HIV serostatus, alcohol use, transactional sex involvement post-HIV diagnosis and non-disclosure of HIV serostatus. Gender-stratified multiple logistic regression models were used for analysis. Non-disclosure of one's serostatus to all sex partners was reported by almost three-fifths of females and two-fifths of males. Predictors of non-disclosure included lack of correct knowledge about HIV and no knowledge of sex partners' HIV serostatus. Among females, recent alcohol consumption also predicted non-disclosure. Among males, 10 + paid sexual partners in the year following HIV diagnosis predicted non-disclosure. Secondary HIV prevention efforts in India require greater focus on HIV disclosure communication and integrated alcohol and sexual risk reduction. PMID:22810892

  17. Non-monogamy and sexual relationship quality among same-sex male couples.

    PubMed

    Parsons, Jeffrey T; Starks, Tyrel J; Gamarel, Kristi E; Grov, Christian

    2012-10-01

    Relationship arrangements about sex with outside partners are common among gay couples, and meaningful distinctions in psychological and behavioral health correlates have been found among nonmonogamous agreement types. The goal of this study was to investigate the relationship between sexual agreements and partners' sexual relationship quality. Data were collected from both members of 161 gay male couples (n = 322 individuals). Couples were categorized as monogamous (52.8%), open (13.0%), monogamish (14.9%), and discrepant (19.3%). We used the actor-partner interdependence model (APIM) to assess associations of relationship arrangement with four aspects of sexual relationship quality: sexual satisfaction, sexual communication, sexual jealousy, and the occurrence of at-least weekly sex between main partners. We found that sexual arrangements were not associated with sexual satisfaction, communication, or frequency. However, monogamous men reported significantly higher levels of sexual jealousy. Our findings indicate that gay men engage in a range of relationship agreements, and nonmonogamous agreements are associated with levels of sexual relationship quality equivalent to monogamous agreements. PMID:22906124

  18. Intervention of D-glucose ameliorates the toxicity of streptozotocin in accessory sex organs of rat

    SciTech Connect

    Vikram, A.; Tripathi, D.N.; Ramarao, P. [Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector-67, S.A.S. Nagar, Punjab-160062 (India); Jena, G.B. [Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector-67, S.A.S. Nagar, Punjab-160062 (India)], E-mail: gbjena@gmail.com

    2008-01-01

    Streptozotocin (STZ) is a naturally occurring compound isolated from Streptomyces achromogens. It is used extensively for inducing diabetes in experimental animals. Diabetes mellitus is known to have proven adverse effects on male sexual organs and their reproductive functions. The atrophy of prostate gland and other organs of the genitourinary tract were observed in experimental diabetic animals. STZ exhibits a structural resemblance to D-glucose due to the presence of sugar moiety in its structure. Pancreatic {beta}-cells mainly contain GLUT1 and GLUT2 glucose transporters. Possibly due to structural resemblance, STZ and D-glucose, share a common recognition site for entry into the {beta}-cells. The objective of the present study is to evaluate the effect of D-glucose on STZ-induced toxicity in accessory sex organs of male rats. Animals were kept on overnight fasting. One group received vehicle and served as negative control, while all other groups were given STZ (45 mg/kg). Animals that received only STZ served as positive control. The effect of D-glucose was studied on STZ treated animals with different dosage of D-glucose (250, 500, 1000 and 2000 mg/kg). Restoration of body weight, plasma glucose and plasma insulin was evident only at 1000 and 2000 mg/kg of D-glucose. The protective effect of D-glucose is evident only when it is administered simultaneously with STZ. In the present investigation, we report that simultaneous administration of D-glucose along with STZ ameliorates STZ-induced toxicity. This is evident from the restoration of accessory sex organ's weight, cellular morphology as well as insulin level.

  19. Have sex differences in spatial ability evolved from male competition for mating and female concern for survival?

    Microsoft Academic Search

    Isabelle Ecuyer-Dab; Michèle Robert

    2004-01-01

    Drawing on the theoretical and empirical foundations of two evolutionary models, we argue that, among humans and other mammals, a twofold selection process would parsimoniously account for sex-linked advantages in spatial contexts. In males, a superiority for both solving navigation-related spatial problems and understanding physical principles that apply to the behavior of projectiles could have been inherited from mating-oriented male

  20. Interventions among male clients of female sex workers in Benin, West Africa: an essential component of targeted HIV preventive interventions

    Microsoft Academic Search

    C M Lowndes; M Alary; A-C Labbe?; C Gnintoungbe?; M Belleau; L Mukenge; H Meda; M Ndour; S Anagonou; A Gbaguidi

    2007-01-01

    Objectives: To assess the impact of interventions targeted towards female sex workers (FSWs) and their male clients on client HIV\\/STI prevalence and sexual behaviour.Methods: From 1993 to 2006, an HIV\\/STI preventive intervention focusing on condom promotion and STI care was implemented among FSWs in Cotonou, Benin, and then expanded to cover their male sexual partners in 2000. The interventions were

  1. Application of condoms on male clients by female sex workers in Yerevan, Armenia: prevalence and correlates.

    PubMed

    Darbinyan, Nelli; Lang, Delia L; Diclemente, Ralph J; Joseph, Jesse B; Markosyan, Karine

    2011-09-01

    This study sought to assess the prevalence of consistent condom application on male clients by female sex workers (FSWs) in Armenia and its association with demographic, psychosocial and behavioural factors. In this cross-sectional study, 120 street-based FSWs aged 20-52 completed an interviewer-administered questionnaire. The primary outcome measure was consistent application of condoms by FSWs on their male clients. A total of 21.7% of participants reported consistently applying condoms on clients. Logistic regression analysis demonstrated that higher condom use self-efficacy (Adjusted Odds Ratio, AOR=1.1; p=0.01), lower perceived condom use barriers (AOR=0.9; p=0.04) and not using douching as a method to prevent STI/HIV (AOR=4.8; p=0.04) significantly predicted consistent condom application. Higher HIV/AIDS knowledge was a marginally significant predictor of condom application (AOR=1.3; p=0.05). Future interventions should address these modifiable factors to encourage FSWs to apply condoms on clients themselves, which may reduce condom failure and exposure to HIV transmission. PMID:21535906

  2. Green light synergistally enhances male sweetpotato weevil response to sex pheromone.

    PubMed

    McQuate, Grant T

    2014-01-01

    Sweetpotato, commercially grown in over 100 countries, is one of the ten most important staple crops in the world. Sweetpotato weevil is a major pest of sweetpotato in most areas of cultivation, the feeding of which induces production in the sweetpotato root of extremely bitter tasting and toxic sesquiterpenes which can render the sweetpotato unfit for consumption. A significant step towards improved management of this weevil species was the identification of a female-produced sex pheromone [(Z)-3-dodecenyl (E)-2-butenoate] to which males are highly attracted. Reported here are results of research that documents a nearly 5-fold increase in male sweetpotato weevil catch in traps baited with this pheromone and a green light provided by a solar-powered, light-emitting diode (LED). The combination of olfactory and night-visible visual cues significantly enhanced trap effectiveness for this nighttime-active insect species. These results provide promise for improved sweetpotato weevil detection and suppression in mass trapping programs. PMID:24675727

  3. Results of a randomised trial of male condom promotion among Madagascar sex workers

    PubMed Central

    Feldblum, P; Hatzell, T; Van Damme, K; Nasution, M; Rasamindrakotroka, A; Grey, T

    2005-01-01

    Objectives: To test the effect of supplementing peer promotion of male condom use with clinic based counselling, measured in terms of STI prevalence and reported male condom use. Methods: 1000 female sex workers in Madagascar were randomised to two study arms: peer education supplemented by individual risk reduction counselling by a clinician (peer + clinic) versus condom promotion by peer educators only (peer only). STI testing was conducted at baseline and 6 months. Behavioural interviews were administered at baseline, 2, 4, and 6 months. Results: At baseline, women in the peer only arm had prevalences of 16.0%, 23.6%, and 12.1% for chlamydia, gonorrhoea, and trichomoniasis respectively, with an aggregate prevalence of 38.2%. Baseline STI prevalences for the peer + clinic arm were slightly lower and 34.1% in aggregate. At 6 months, aggregate STI prevalence increased in the peer only arm to 41.4%, whereas the aggregate prevalence diminished slightly to 32.1% in the peer + clinic arm. In logistic regression analyses, the estimated odds ratios (ORs) for chlamydia, gonorrhoea, trichomoniasis, and aggregate STI were 0.7 (95% confidence interval 0.4 to 1.0), 0.7 (0.5 to 1.0), 0.8 (0.6 to 1.2), and 0.7 (0.5 to 0.9) respectively, comparing the peer + clinic arm with the peer only arm. The logistic regression OR for reported condom use with clients in the past 30 days increased from 1.1 at 2 months to 1.8 at 6 months, comparing the peer + clinic arm with the peer only arm, and was 1.4 overall (1.1 to 1.8). Adjustment for baseline factors changed the regression results little. Conclusions: The impact of male condom promotion on behaviour can be heightened through more concentrated counselling on risk reduction. Persistently high STI prevalence despite increases in reported condom use by sex workers supports the need for multidimensional control programmes. PMID:15800098

  4. Perceptions about HIV and Condoms and Consistent Condom Use among Male Clients of Commercial Sex Workers in the Philippines

    ERIC Educational Resources Information Center

    Regan, Rotrease; Morisky, Donald E.

    2013-01-01

    Because consistent condom use is an effective strategy in the prevention of sexually transmitted infections and HIV transmission, it is important to examine social cognitive influences of consistent condom use not only among female sex workers (FSWs) but also among their male clients, for whom less is known. Because little is known about how HIV…

  5. Effect of Patients' Sex, Physicians' Attributes, and Patients' Complaint on Patients' Preference for Male vs Female Physicians.

    ERIC Educational Resources Information Center

    Ross, F. Susan Ackerman; Sochat N.

    In view of the dramatic increase in the number of women graduating from medical school in each of the past five years, this study explored patients' preferences for male versus female physicians. A questionnaire was designed to determine the patients' physician preferences in regard to each of the following areas: the sex of patient; the physician…

  6. Sex differentiation in bilaterally allophenic animals produced by cloning of two bipartite male\\/female chimaeras of Lineus sanguineus

    Microsoft Academic Search

    S. SIVARADJAM

    SUMMARY Two bipartite chimaeras were constructed in Lineus sanguineus by grafting the lateral halves from a phenotypically dark-brown male onto the anatomically complementary halves from a phenotypically light-brown female. Regeneration of a large number of pieces tran- sected from these two bilaterally allogeneic chimaeras produced two clones of bilaterally allophenic nemertines (c?\\/$ and ?\\/Sex differentiation in the cloned worms

  7. “Working together to reach a goal”: MSM's Perceptions of Dyadic HIV Care for Same-Sex Male Couples

    PubMed Central

    Goldenberg, Tamar; Clarke, Donato; Stephenson, Rob

    2014-01-01

    Introduction Same-sex serodiscordant male dyads represent a high priority risk group, with approximately one to two-thirds of new HIV infections among MSM attributable to main partnerships. Early initiation and adherence to highly active antiretroviral treatment (HAART) is a key factor in HIV prevention and treatment; however, adherence to HAART in the U.S. is low, with poor retention throughout the continuum of care. This study examines MSM's perceptions of dyadic HIV treatment across the continuum of care to understand preferences for how care may be sought with a partner. Methods We conducted five focus group discussions (FGDs) in Atlanta, GA with 35 men who report being in same-sex male partnerships. Participants discussed perceptions of care using scenarios of a hypothetical same-sex male couple who recently received serodiscordant or seroconcordant positive HIV results. Verbatim transcripts were segmented thematically and systematically analyzed to examine patterns in responses within and between participants and FGDs. Results Participants identified the need for comprehensive dyadic care and differences in care for seroconcordant positive versus serodiscordant couples. Participants described a reciprocal relationship between comprehensive dyadic care and positive relationship dynamics. This combination was described as reinforcing commitment, ultimately leading to increased accountability and treatment adherence. Discussion Results indicate that the act of same-sex male couples “working together to reach a goal” may increase retention to HIV care across the continuum if care is comprehensive, focuses on both individual and dyadic needs, and promotes positive relationship dynamics. PMID:24126448

  8. The ovary retains male potential after the thermosensitive period for sex determination in the turtle Emys orbicularis

    Microsoft Academic Search

    Mireille Dorizzi; Noëlle Richard-Mercier; Claude Pieau

    1996-01-01

    Emys orbicularis is a turtle with temperature-dependent sex determination. The thermosensitive period (TSP) lies between embryonic stages 16 and 22. Gonadal differentiation begins during this period involving oestrogens. Treatment with oestrogens during TSP results in the differentiation of ovaries at a male-producing temperature (25° C), whereas treatment with an antioestrogen (tamoxifen) or with nonsteroidal aromatase inhibitors results in gonadal masculinization

  9. Sex Differences and Opposite Effects of Stress on Dendritic Spine Density in the Male Versus Female Hippocampus

    E-print Network

    Shors, Tracey J.

    Sex Differences and Opposite Effects of Stress on Dendritic Spine Density in the Male Versus Female for Collaborative Neuroscience, Rutgers University, Piscataway, New Jersey 08854 Dendritic spines are postsynaptic, when estrogen levels are elevated, have a greater density of apical dendritic spines on pyramidal

  10. Differential Suicide Rates in Typologies of Child Sex Offenders in a 6-year Consecutive Cohort of Male Suicides

    Microsoft Academic Search

    Colin Pritchard; Elizabeth King

    2005-01-01

    Earlier research identified 3 typologies of Child Sex Offenders [CSO] with high rates of suicide. To test this finding suicide rates of 3 types of CSO were compared in a 6-year cohort of regional suicides. All male suicides were identified from Coroners” inquest files and CSO data drawn from police records to calculate CSO suicide rates. The results show that

  11. Discriminating Males and Unpredictable Females: Males Differentiate Self-Similar Facial Cues More than Females in the Judgment of Opposite-Sex Attractiveness

    PubMed Central

    Zhuang, Jin-Ying; Zhang, Sen; Xu, Jing; Hu, Die

    2014-01-01

    Attractiveness judgment in the context of mate preferences is thought to reflect an assessment of mate quality in relation to an absolute scale of genetic fitness and a relative scale of self-similarity. In this study, subjects judged the attractiveness and trustworthiness of faces in composite images that were manipulated to produce self-similar (self-resemblance) and dissimilar (other-resemblance) images. Males differentiated between self- and other-resemblance as well as among different degrees of self-resemblance in their attractiveness ratings; females did not. Specifically, in Experiment 1, using a morphing technique, we created previously unseen face images possessing different degrees (0%, 30%, 40%, or 50%) of incorporation of the subject's images (different degrees of self-resemblance) and found that males preferred images that were closer to average (0%) rather than more self-similar, whereas females showed no preference for any degree of self-similarity. In Experiment 2, we added a pro-social question about trustworthiness. We replicated the Experiment 1 attractiveness rating results and further found that males differentiated between self- and other-resemblance for the same degree of composites; women did not. Both males and females showed a similar preference for self-resemblances when judging trustworthiness. In conclusion, only males factored self-resemblance into their attractiveness ratings of opposite-sex individuals in a manner consistent with cues of reproductive fitness, although both sexes favored self-resemblance when judging trustworthiness. PMID:24594644

  12. Age, Sex, and Telomere Dynamics in a Long-Lived Seabird with Male-Biased Parental Care

    PubMed Central

    Young, Rebecca C.; Kitaysky, Alexander S.; Haussmann, Mark F.; Descamps, Sebastien; Orben, Rachael A.; Elliott, Kyle H.; Gaston, Anthony J.

    2013-01-01

    The examination of telomere dynamics is a recent technique in ecology for assessing physiological state and age-related traits from individuals of unknown age. Telomeres shorten with age in most species and are expected to reflect physiological state, reproductive investment, and chronological age. Loss of telomere length is used as an indicator of biological aging, as this detrimental deterioration is associated with lowered survival. Lifespan dimorphism and more rapid senescence in the larger, shorter-lived sex are predicted in species with sexual size dimorphism, however, little is known about the effects of behavioral dimorphism on senescence and life history traits in species with sexual monomorphism. Here we compare telomere dynamics of thick-billed murres (Urialomvia), a species with male-biased parental care, in two ways: 1) cross-sectionally in birds of known-age (0-28 years) from one colony and 2) longitudinally in birds from four colonies. Telomere dynamics are compared using three measures: the telomere restriction fragment (TRF), a lower window of TRF (TOE), and qPCR. All showed age-related shortening of telomeres, but the TRF measure also indicated that adult female murres have shorter telomere length than adult males, consistent with sex-specific patterns of ageing. Adult males had longer telomeres than adult females on all colonies examined, but chick telomere length did not differ by sex. Additionally, inter-annual telomere changes may be related to environmental conditions; birds from a potentially low quality colony lost telomeres, while those at more hospitable colonies maintained telomere length. We conclude that sex-specific patterns of telomere loss exist in the sexually monomorphic thick-billed murre but are likely to occur between fledging and recruitment. Longer telomeres in males may be related to their homogamous sex chromosomes (ZZ) or to selection for longer life in the care-giving sex. Environmental conditions appeared to be the primary drivers of annual changes in adult birds. PMID:24023967

  13. Male Sex Is Independently Associated with Faster Disability Accumulation in Relapse-Onset MS but Not in Primary Progressive MS

    PubMed Central

    Ribbons, Karen Ann; McElduff, Patrick; Boz, Cavit; Trojano, Maria; Izquierdo, Guillermo; Duquette, Pierre; Girard, Marc; Grand’Maison, Francois; Hupperts, Raymond; Grammond, Pierre; Oreja-Guevara, Celia; Petersen, Thor; Bergamaschi, Roberto; Giuliani, Giorgio; Barnett, Michael; van Pesch, Vincent; Amato, Maria-Pia; Iuliano, Gerardo; Fiol, Marcela; Slee, Mark; Verheul, Freek; Cristiano, Edgardo; Fernandez-Bolanos, Ricardo; Saladino, Maria-Laura; Rio, Maria Edite; Cabrera-Gomez, Jose; Butzkueven, Helmut; van Munster, Erik; Den Braber-Moerland, Leontien; La Spitaleri, Daniele; Lugaresi, Alessandra; Shaygannejad, Vahid; Gray, Orla; Deri, Norma; Alroughani, Raed; Lechner-Scott, Jeannette

    2015-01-01

    Background Multiple Sclerosis is more common in women than men and females have more relapses than men. In a large international cohort we have evaluated the effect of gender on disability accumulation and disease progression to determine if male MS patients have a worse clinical outcome than females. Methods Using the MSBase Registry, data from 15,826 MS patients from 25 countries was analysed. Changes in the severity of MS (EDSS) were compared between sexes using a repeated measures analysis in generalised linear mixed models. Kaplan-Meier analysis was used to test for sex difference in the time to reach EDSS milestones 3 and 6 and the secondary progressive MS. Results In relapse onset MS patients (n = 14,453), males progressed significantly faster in their EDSS than females (0.133 vs 0.112 per year, P<0.001,). Females had a reduced risk of secondary progressive MS (HR (95% CI) = 0.77 (0.67 to 0.90) P = 0.001). In primary progressive MS (n = 1,373), there was a significant increase in EDSS over time in males and females (P<0.001) but there was no significant sex effect on the annualized rate of EDSS change. Conclusion Among registrants of MSBase, male relapse-onset patients accumulate disability faster than female patients. In contrast, the rate of disability accumulation between male and female patients with primary progressive MS is similar. PMID:26046348

  14. CHALLENGES IN BIODEGRADATION OF TRACE ORGANIC CONTAMINANTS-GASOLINE OXYGENATES AND SEX HORMONES

    EPA Science Inventory

    Advances in analytical methods have led to the identification of several classes of organic chemicals that are associated with adverse environmental impacts. Two such classes of organic chemicals, gasoline oxygenates and sex hormones, are used to illustrate challenges associated ...

  15. Exogenous application of estradiol to eggs unexpectedly induces male development in two turtle species with temperature-dependent sex determination.

    PubMed

    Warner, Daniel A; Addis, Elizabeth; Du, Wei-guo; Wibbels, Thane; Janzen, Fredric J

    2014-09-15

    Steroid hormones affect sex determination in a variety of vertebrates. The feminizing effects of exposure to estradiol and the masculinizing effects of aromatase inhibition during development are well established in a broad range of vertebrate taxa, but paradoxical findings are occasionally reported. Four independent experiments were conducted on two turtle species with temperature-dependent sex determination (Chrysemys picta and Chelydra serpentina) to quantify the effects of egg incubation temperature, estradiol, and an aromatase inhibitor on offspring sex ratios. As expected, the warmer incubation temperatures induced female development and the cooler temperatures produced primarily males. However, application of an aromatase inhibitor had no effect on offspring sex ratios, and exogenous applications of estradiol to eggs produced male offspring across all incubation temperatures. These unexpected results were remarkably consistent across all four experiments and both study species. Elevated concentrations of estradiol could interact with androgen receptors or inhibit aromatase expression, which might result in relatively high testosterone concentrations that lead to testis development. These findings add to a short list of studies that report paradoxical effects of steroid hormones, which addresses the need for a more comprehensive understanding of the role of sex steroids in sexual development. PMID:24954686

  16. AIDS knowledge, risk behaviors, and factors related to condom use among male commercial sex workers and male tourist clients in Bali, Indonesia.

    PubMed

    Ford, K; Wirawan, D N; Fajans, P; Thorpe, L

    1995-07-01

    Interviews conducted in 1992-93 with 80 male commercial sex workers in Bali, Indonesia, and 100 of their tourist clients revealed low levels of accurate knowledge about acquired immunodeficiency syndrome (AIDS) and widespread high-risk sexual behaviors. Although most male sex workers were aware of AIDS, 30% did not know that healthy-appearing persons could be infected. The mean number of clients in the week preceding the interview was 2.8 (range, 0-12); 61% had engaged in anal intercourse in that period. Condom use with clients averaged 48% for receptive anal intercourse, 55% for insertive anal intercourse, and 14-17% for oral intercourse; these rates were 19%, 33%, and 0%, respectively, for unpaid partners. Only 30% of clients serviced by male prostitutes insisted on condom use. Factors related to condom use with commercial clients were condom beliefs, self-efficacy, perceived susceptibility to infection, and knowledge of sexually transmitted diseases. The tourist clients, 60% of whom were from Europe and 25% from Australia, were significantly older (mean age, 38.4 years) than the sex workers. 64% reported a history of STD infection, primarily gonorrhea. In the week before the interview, clients had an average of 1.7 paid and 0.3 unpaid partners and 53% engaged in anal intercourse. Condom use was 75% for receptive and 69% for insertive anal intercourse. Although 87% of tourists brought condoms to Bali, only 62% knew of a local source. Factors related to condom use with a commercial sex worker were condom beliefs and self-efficacy. PMID:7546421

  17. HIV-Related Risk Behaviors and History of Sexually Transmitted Diseases Among Male Migrants Who Patronize Commercial Sex in China

    PubMed Central

    WANG, BO; LI, XIAOMING; STANTON, BONITA; FANG, XIAOYI; LIN, DANHUA; MAO, RONG

    2007-01-01

    Background and Objective Men who pay for sexual services are at increased risk for HIV/sexually transmitted disease. Data on the sociodemographic and behavioral characteristics of such men in China are limited. Study Design Two cross-sectional surveys, using similar instruments, were completed among Chinese migrants in Beijing, Shanghai, and Nanjing in 2002. A total of 1304 rural-to-urban migrant men from community settings (“community sample”) and 465 migrant men attending sexually transmitted disease clinics (“STD clinic sample”) were included in the current study. Results Ten percent of men in the community sample and 32.7% of men in the STD clinic sample reported having ever paid for sex. Nearly 20% of clients from the community sample and 60% of clients from the STD clinic sample reported a history of STDs. For both the community and STD clinic samples, working at industrial or construction sectors, multiple sexual partners, regular sex partner having sex with others, and a history of drug use were associated with being a male client. In addition, perceived peer sexual risk and perceived vulnerability to STD were associated with being a male client in the community sample, and a history of STD and being tested for STD/HIV were associated with being a male client in the STD sample. Conclusion Male migrants who paid for sex in China were vulnerable to HIV/STDs. HIV prevention efforts should target young migrant men who work at factory and construction sectors. STD clinics may be important sites for outreach and intervention efforts among male clients. PMID:16755272

  18. Sex and attitude distortion: Ability of females and males to fake liberal and conservative positions regarding changing sex roles

    Microsoft Academic Search

    Paula J. Jean; Cecil R. Reynolds

    1984-01-01

    Scales designed to measure attitudes toward changing sex roles are vulnerable to the effects of social desirability. The purpose of this study was to assess the differences in this vulnerability or fakeability between an older scale, the Attitudes Toward Women Scale (AWS) and a more current scale, the Bias in Attitudes Survey (BIAS). Results suggest that, when asked to do

  19. The Animal = Male Hypothesis: Children's and Adults' Beliefs About the Sex of Non–Sex-Specific Stuffed Animals

    Microsoft Academic Search

    Jennifer R. Lambdin; Kristen M. Greer; KariSelby Jibotian; KellyRice Wood

    2003-01-01

    The Animal = Male Hypothesis, a variation of Silveira's People = Male Hypothesis (Silveira, 1980), was examined. In Study 1, children ages 3–10 years and adults told stories about a gender-neutral stuffed animal, in Study 2 children ages 5–6 years told stories about 3 neutral and 3 feminine animals, and in Study 3 children ages 5–7 years told stories about

  20. The strength of male-driven evolution that is, the magnitude of the sex ratio of mutation rate has been a controversial

    E-print Network

    Yi, Soojin

    650 The strength of male-driven evolution ­ that is, the magnitude of the sex ratio of mutation mutation rate in males than in females has been well accepted, the magnitude of the male-to-female ratio () of mutation rate remains a point of contention. Knowing the magnitude of is important because it is related

  1. Redundancy in a chemical signal: Behavioral responses of male Trichoplusia ni to a 6Component sex pheromone blend

    Microsoft Academic Search

    C. E. Linn; L. B. Bjostad; J. W. Du; W. L. Roelofs

    1984-01-01

    The flight response of maleTrichoplusia ni was observed in a flight tunnel to a sex pheromone blend composed of six components:Z7–12:Ac, 12:Ac,Z5-12:Ac, 11-12:Ac,Z7-14:Ac, and Z9-14:Ac. The number of males reaching a 3000-µg source of this blend was > 95%, equal to that observed to female glands and significantly greater than with the previously identified two-component blend (Z7-12:Ac + 12:Ac). In

  2. Covariance of paternity and sex with laying order explains male bias in extra-pair offspring in a wild bird population.

    PubMed

    Vedder, Oscar; Magrath, Michael J L; van der Velde, Marco; Komdeur, Jan

    2013-10-23

    It has been hypothesized that parents increase their fitness by biasing the sex ratio of extra-pair offspring (EPO) towards males. Here, we report a male bias among EPO in a wild population of blue tits (Cyanistes caeruleus). This resulted from a decline in both the proportion of males and EPO over the laying order of eggs in the clutch. However, previous studies suggest that, unlike the decline in EPO with laying order, the relationship between offspring sex ratio and laying order is not consistent between years and populations in this species. Hence, we caution against treating the decline in proportion of males with laying order, and the resulting male bias among EPO, as support for the above hypothesis. Variable patterns of offspring sex and paternity over the laying order may explain inconsistent associations between offspring sex and paternity, between and within species. PMID:24026349

  3. Short-term treatment of adult male zebrafish (Danio Rerio) with 17?-ethinyl estradiol affects the transcription of genes involved in development and male sex differentiation.

    PubMed

    Reyhanian Caspillo, Nasim; Volkova, Kristina; Hallgren, Stefan; Olsson, Per-Erik; Porsch-Hällström, Inger

    2014-08-01

    The synthetic estrogen 17?-ethinyl estradiol (EE2) disturbs reproduction and causes gonadal malformation in fish. Effects on the transcription of genes involved in gonad development and function that could serve as sensitive biomarkers of reproductive effects in the field is, however, not well known. We have studied mRNA expression in testes and liver of adult zebrafish (Danio rerio) males treated with 0, 5 or 25 ng/L EE2for 14 days. qPCR analysis showed that the mRNA expression of four genes linked to zebrafish male sex determination and differentiation, Anti-Mullerian Hormone, Double sex and mab-related protein, Sry-related HMG box-9a and Nuclear receptor subfamily 5 group number 1b were significantly decreased by 25 ng/L, but not 5 ng/L EE2 compared with the levels in untreated fish. The decreased transcription was correlated with a previously shown spawning failure in these males (Reyhanian et al., 2011. Aquat Toxicol 105, 41-48), suggesting that decreased mRNA expression of genes regulating male sexual function could be involved in the functional sterility. The mRNA level of Cytochrome P-45019a, involved in female reproductive development, was unaffected by hormone treatment. The transcription of the female-specific Vitellogenin was significantly induced in testes. While testicular Androgen Receptor and the Estrogen Receptor-alpha mRNA levels were unchanged, Estrogen receptor-beta was significantly decreased by 25 ng/L EE2. Hepatic Estrogen Receptor-alpha mRNA was significantly increased by both exposure concentrations, while Estrogen Receptor-beta transcription was unaltered. The decreased transcription of male-predominant genes supports a demasculinization of testes by EE2 and might reflect reproductive disturbances in the environment. PMID:24747828

  4. Estimation of the Number of Sex Alleles and Queen Matings from Diploid Male Frequencies in a Population of APIS MELLIFERA

    PubMed Central

    Adams, Julian; Rothman, Edward D.; Kerr, Warwick E.; Paulino, Zila L.

    1977-01-01

    The distribution of diploid males in a population of Apis mellifera was obtained by direct examination of the sexual phenotypes of the larvae. Using these data, estimates are derived for the number of sex alleles and the number of matings undergone by the queen. The number of sex alleles is estimated to be 18.9. The estimate is larger than previous ones, which have ranged between 10 and 12. However, the increase in the number of sex alleles can be explained by the large effective population number for our data. The best estimator of the number of matings by a queen is a maximum likelihood type that assumes a prior distribution on the number of matings. For the data presented here, this estimate is 17.3. This estimate is compared to others in the literature obtained by different approaches. PMID:892423

  5. THE POSTERIOR BED NUCLEUS OF THE STRIA TERMINALIS MEDIATES OPPOSITE SEX ODOR PREFERENCE IN MALE SYRIAN HAMSTERS (MESOCRICETUS AURATUS)

    Microsoft Academic Search

    In Syrian hamsters, social behavior is mediated exclusively by chemosensory cues and circulating gonadal steroid hormones. Where these two signals are processed in the brain is unknown, but the posterior bed nucleus of the stria terminalis (pBNST) has been suggested as a candidate site. Therefore, we tested male hamsters' preference for opposite-sex odors following excitotoxic lesions of the pBNST. Lesions

  6. Sex ratio and spatial pattern of males and females in the dioecious sandhill shrub, Ceratiola ericoides ericoides (Empetraceae) Michx

    Microsoft Academic Search

    John Paul Schmidt

    2008-01-01

    Sex ratio, size, age, and spatial pattern were investigated for males and females of the dioecious shrub Ceratiola ericoides ericoides (Empetraceae) Michx. within seven mapped populations in Georgia and South Carolina, USA. Among the sites studied, two are\\u000a regularly burned and one site long-unburned. Age was estimated from node counts of individual shrubs. Only one (fire-suppressed)\\u000a population showed a female-biased

  7. Sex, Organs and Audiotape: A Discourse Analytic Approach to Talking about Heterosexual Sex and Relationships

    Microsoft Academic Search

    Jackie Gilfoyle; Jonathan Wilson; Br Own

    1992-01-01

    This article examines talk about sex and heterosexual relationships, based on a study of 12 women and 13 men who participated in semi-structured interviews, in order to identify the `discourses' of sexuality which inform talk about heterosexual sex. One theme in talk about heterosexuality can be understood through the `pseudo-reciprocal gift discourse': women are described as `giving' themselves to men,

  8. A protective effect of circumcision among receptive male sex partners of Indian men who have sex with men.

    PubMed

    Schneider, John A; Michaels, Stuart; Gandham, Sabitha R; McFadden, Rachel; Liao, Chuanhong; Yeldandi, Vijay V; Oruganti, Ganesh

    2012-02-01

    The role of circumcision in the transmission of human immunodeficiency virus (HIV) among men who have sex with men (MSM) in resource restricted regions is poorly understood. This study explored the association of circumcision with HIV seroprevalence, in conjunction with other risk factors such as marriage and sex position, for a population of MSM in India. Participants (n = 387) were recruited from six drop-in centers in a large city in southern India. The overall HIV prevalence in this sample was high, at 18.6%. Bivariate and multivariable analyses revealed a concentration of risk among receptive only, married, and uncircumcised MSM, with HIV prevalence in this group reaching nearly 50%. The adjusted odds of HIV infection amongst circumcised men was less than one fifth that of uncircumcised men [adjusted odds ratio (AOR) 0.17; 95% CI 0.07-0.46; P < 0.001]. Within the group of receptive only MSM, infection was found to be lower among circumcised individuals (AOR, 0.30, 95% CI 0.12-0.76; P < 0.05) in the context of circumcised MSM engaging in more UAI, having a more recent same sex encounter and less lubricant use when compared to uncircumcised receptive men. To further explain these results, future studies should focus on epidemiologic analyses of risk, augmented by social and sexual network analyses of MSM mixing. PMID:21681562

  9. A protective effect of circumcision among receptive male sex partners of Indian men who have sex with men

    PubMed Central

    Schneider, John A.; Michaels, Stuart; Rani, Sabitha; McFadden, Rachel; Liao, Chuanhong; Yeldandi, Vijay; Oruganti, Ganesh

    2013-01-01

    The role of circumcision in the transmission of human immunodeficiency virus (HIV) among men who have sex with men (MSM) in resource restricted regions is poorly understood. This study explored the association of circumcision with HIV seroprevalence, in conjunction with other risk factors such as marriage and sex position, for a population of MSM in India. Participants (n=387) were recruited from six drop in centers in a large city in southern India. The overall HIV prevalence in this sample was high, at 18.6%. Bivariate and multivariable analyses revealed a concentration of risk among receptive only, married, and uncircumcised MSM, with HIV prevalence in this group reaching nearly 50%. The adjusted odds of HIV infection amongst circumcised men was less than one-fifth that of uncircumcised men (adjusted odds ratio (AOR, 0.17; 95% 0.07-0.46). Within the group of receptive only MSM, infection was found to be lower amongst circumcised individuals (AOR, 0.23, 95% CI 0.09 – 0.61) in the context of circumcised MSM engaging in more UAI, having a more recent same sex encounter and less lubricant use when compared to uncircumcised men. To further explain these results, future studies should focus less on traditional epidemiologic analyses of risk that are typically conducted in these settings and more on better understanding MSM partnering patterns including formal analyses of potentially overlapping social and sexual networks. PMID:21681562

  10. Offspring sex ratios reflect lack of repayment by auxiliary males in a cooperatively breeding passerine

    Microsoft Academic Search

    Claire W. Varian-Ramos; Jordan Karubian; Vanessa Talbott; Irma Tapia; Michael S. Webster

    2010-01-01

    The repayment hypothesis posits that primary sex ratios in cooperative species should be biased towards the helping sex because\\u000a these offspring “repay” a portion of their cost through helping behavior and therefore are less expensive to produce. However,\\u000a many cooperatively breeding birds and mammals do not show the predicted bias in the primary sex ratio. Recent theoretical\\u000a work has suggested

  11. The Sertoli Cell Only Syndrome and Glaucoma in a Sex – Determining Region Y (SRY) Positive XX Infertile Male

    PubMed Central

    Jain, Manish; V, Veeramohan; Chaudhary, Isha; Halder, Ashutosh

    2013-01-01

    The XX male syndrome is a rare genetic disorder. The phenotype is variable; it ranges from a severe impairment of the external genitalia to a normal male phenotype with infertility. It generally results from an unequal crossing over between the short arms of the sex chromosomes (X and Y). We are reporting a case of a 38-year-old man who presented with infertility and the features of hypogonadism and glaucoma. The examinations revealed normal external male genitalia, soft small testes, gynaecomastia and glaucoma. The semen analysis showed azoospermia. The serum gonadotropins were high, with low Anti Mullerian Hormone (AMH) and Inhibin B levels. The chromosomal analysis demonstrated a 46, XX karyotype. Fluorescent In-Situ Hybridization (FISH) and Polymerase Chain Reaction (PCR) revealed the presence of a Sex-determining Region Y (SRY). Testicular Fine Needle Aspiration Cytology (FNAC) revealed the Sertoli Cell Only Syndrome (SCOS). The presence of only Sertoli Cells in the testes, with glaucoma in the XX male syndrome, to our knowledge, has not been reported in the literature. PMID:23998093

  12. Concurrent modulation of neuronal and behavioural olfactory responses to sex and host plant cues in a male moth.

    PubMed

    Kromann, Sophie H; Saveer, Ahmed M; Binyameen, Muhammad; Bengtsson, Marie; Birgersson, Göran; Hansson, Bill S; Schlyter, Fredrik; Witzgall, Peter; Ignell, Rickard; Becher, Paul G

    2015-01-22

    Mating has profound effects on animal physiology and behaviour, not only in females but also in males, which we show here for olfactory responses. In cotton leafworm moths, Spodoptera littoralis, odour-mediated attraction to sex pheromone and plant volatiles are modulated after mating, producing a behavioural response that matches the physiological condition of the male insect. Unmated males are attracted by upwind flight to sex pheromone released by calling females, as well as to volatiles of lilac flowers and green leaves of the host plant cotton, signalling adult food and mating sites, respectively. Mating temporarily abolishes male attraction to females and host plant odour, but does not diminish attraction to flowers. This behavioural modulation is correlated with a response modulation in the olfactory system, as shown by electro-physiological recordings from antennae and by functional imaging of the antennal lobe, using natural odours and synthetic compounds. An effect of mating on the olfactory responses to pheromone and cotton plant volatiles but not to lilac flowers indicates the presence of functionally independent neural circuits within the olfactory system. Our results indicate that these circuits interconnect and weigh perception of social and habitat odour signals to generate appropriate behavioural responses according to mating state. PMID:25621329

  13. Male reproductive patterns in nonhibernating bats

    Microsoft Academic Search

    P. H. Krutzsch

    Summary. Knowledge relative to the reproduction of nonhibernating bats is reviewed. Events in the male, as they are now understood, are summarized for all families for which data exist. Attention is given to the wide species diversity of male accessory sex organs in respect to gross structure and glandular complement. Stability or variability of organization of the male reproductive system

  14. Cross-sex hormone treatment in male-to-female transsexual persons reduces serum brain-derived neurotrophic factor (BDNF).

    PubMed

    Fuss, Johannes; Hellweg, Rainer; Van Caenegem, Eva; Briken, Peer; Stalla, Günter K; T'Sjoen, Guy; Auer, Matthias K

    2015-01-01

    Serum levels of brain-derived neurotrophic factor (BDNF) are reduced in male-to-female transsexual persons (MtF) compared to male controls. It was hypothesized before that this might reflect either an involvement of BDNF in a biomechanism of transsexualism or to be the result of persistent social stress due to the condition. Here, we demonstrate that 12 month of cross-sex hormone treatment reduces serum BDNF levels in male-to-female transsexual persons independent of anthropometric measures. Participants were acquired through the European Network for the Investigation of Gender Incongruence (ENIGI). Reduced serum BDNF in MtF thus seems to be a result of hormonal treatment rather than a consequence or risk factor of transsexualism. PMID:25498415

  15. Male rats with same sex preference show high experimental anxiety and lack of anxiogenic-like effect of fluoxetine in the plus maze test.

    PubMed

    García-Cárdenas, Nallely; Olvera-Hernández, Sandra; Gómez-Quintanar, Blanca Nelly; Fernández-Guasti, Alonso

    2015-08-01

    Homosexual men show a 2-4 higher risk to suffer anxiety in comparison with heterosexuals. It is unknown if biological factors collaborate to increase such incidence. Fluoxetine produces differential brain activation in homosexuals as compared with heterosexuals, suggesting that it may produce a divergent behavioral effect dependant on sex-preference. The first aim was to evaluate experimental anxiety in male rats that show same-sex preference in the elevated plus maze (EPM). The second goal explored the putative differential effect of fluoxetine (10mg/kg) in male rats with female and same-sex preference in the EPM. To induce same-sex preference males were prenatally treated with letrozole (0.56?g/kg, 10-20 gestation days), while controls were males prenatally treated with letrozole that retain female-preference or which mothers received oil. In both groups we found animals with male preference, but the proportion was higher in males that prenatally received letrozole (10 vs. 27%). Males with same-sex preference spent less time and showed lower number of entries to the open arms of the EPM than males that prefer females, regardless of the prenatal treatment. In males with female preference, fluoxetine reduced the time spent and number of entries to the open arms that was absent in males with same-sex preference. These data suggest that biological factors contribute to the high levels of anxiety in subjects with same-sex preference and that fluoxetine in men may produce a divergent action depending on sexual orientation. PMID:26044966

  16. Sex and social networking: the influence of male presence on social structure of female shark groups

    Microsoft Academic Search

    David M. P. Jacoby; Dheeraj S. Busawon; David W. Sims

    2010-01-01

    Marine predators such as sharks often form single-sex aggregations as part of their diel behavioral cycle. Such aggregations are potentially driven by contrasting reproductive and behavioral strategies between the sexes, leading to distinct sexual segregation. There is, however, no experimental evidence that such predator aggregations are governed by intrinsic social systems, demonstrating long-term temporal stability. Social network structure, temporal stability,

  17. High-glucose diets have sex-specific effects on aging in C. elegans: toxic to hermaphrodites but beneficial to males.

    PubMed

    Liggett, Marjorie R; Hoy, Michael J; Mastroianni, Michael; Mondoux, Michelle A

    2015-06-01

    Diet and sex are important determinants of lifespan. In humans, high sugar diets, obesity, and type 2 diabetes correlate with decreased lifespan, and females generally live longer than males. The nematode Caenorhabditis elegans is a classical model for aging studies, and has also proven useful for characterizing the response to high-glucose diets. However, studies on male animals are lacking. We found a surprising dichotomy: glucose regulates lifespan and aging in a sex-specific manner, with beneficial effects on males compared to toxic effects on hermaphrodites. High-glucose diet resulted in greater mobility with age for males, along with a modest increase in median lifespan. In contrast, high-glucose diets decrease both lifespan and mobility for hermaphrodites. Understanding sex-specific responses to high-glucose diets will be important for determining which evolutionarily conserved glucose-responsive pathways that regulate aging are "universal" and which are likely to be cell-type or sex-specific. PMID:26143626

  18. Sex-dependent activities of quinone reductases in rabbits indicate higher risk of bladder cancer in the male.

    PubMed

    Mohandas, J; Chennell, A F; Duggin, G G; Horvath, J S; Tiller, D J

    1986-03-01

    The distribution of NADPH-dependent quinone reductase and NADPH-cytochrome P-450 reductase activities was determined in the urinary bladders of male and female rabbits. In urinary bladder transitional epithelium (UBTE) and in urinary bladder non-transitional tissue (UBNT) microsomal quinone reductases demonstrated significant (P less than 0.05) sex-dependent differences in the case of both dicoumarol-insensitive (male greater than female) and dicoumarol-sensitive or DT-diaphorase (female greater than male) activities. Microsomal NADPH-cytochrome P-450 reductase activities in UBTE and in UBNT were found to be similar in male and female rabbits. The activities of microsomal and cytosolic quinone reductases and the activity of microsomal NADPH-cytochrome P-450 reductase in UBNT were much lower than those in UBTE. NADPH-cytochrome P-450 reductase and similar flavo-enzymes activate quinones via one-electron reduction into semiquinone free radicals, which then react with molecular oxygen, forming superoxide anions. DT-diaphorase acts as a detoxifying enzyme by converting many quinones via a unique two-electron reduction into less reactive hydroquinones, enabling their excretion as water-soluble conjugates. Since UBTE contains substantial activities of prostaglandin H synthase (PHS) and NADPH-cytochrome P-450 reductase, unlike UBNT, the toxicity and carcinogenicity of xenobiotics which are either quinones or form quinones in situ through the mediation of PHS would be high in UBTE. The risk of carcinogenicity of quinones in UBTE would be higher in male rabbits than in female rabbits due to sex-dependent differences in the relative proportions of the one-electron reduction pathway, represented by NADPH-cytochrome P-450 reductase, and the two-electron reduction pathway, represented by DT-diaphorase (female greater than male). PMID:2419007

  19. SEX PHEROMONE ACTIVITY OF THE MOLTING HORMONE, CRUSTECDYSONE, ON MALE CRABS

    E-print Network

    was placed in the holding tank with them. Each male became active, walked about on the tips of its dactyls elevated its cephalothorax in a typical stance was noted. Six crabs were timed at each concentration of 337 #12;crustecdysone, and fresh male crabs were used for each different concentration. The male crabs

  20. Two-sex matrix models in assessing population viability: when do male dynamics matter?

    E-print Network

    Gerber, Leah R.

    targeted for management may therefore respond differ- ently for males and females and for different to estimate risk of extinction. In this paper, we examine the importance of including both males and females population dynamics. Male and female mortality appear to exhibit different dynamics for a wide range of taxa

  1. Genetic method of combating the cabbage root fly. Part II. Localization of factor determining male sex in the cabbage root fly Delia brassicae bouche

    SciTech Connect

    Samoilov, Yu.B.

    1986-05-01

    Cytogenetic analysis was conducted of 15 lines of the cabbage root fly with hereditary semisterility in the form of late embryonic lethals (LEL). In 14 lines (93%), the presence of translocations was noted. A high yield of translocations linked with the male sex was obtained, which was caused by the fact that determination of male sex in this species is apparently associated with the largest chromosome 6, and not with chromosome 1, as was believed previously.

  2. The Impact of Single-Sex Education on Male and Female Gains in Mathematics and Reading at the Elementary Level in a Selected School in North Carolina

    ERIC Educational Resources Information Center

    O'Neill, Lisa

    2011-01-01

    The gender gap in achievement and the increasing awareness of differences between male and female cognitive development have ignited a growing interest in single-sex education. No Child Left Behind legislation and amendments to Title IX legislation have increased the number of schools in America offering single-sex education. This 2-year…

  3. On same-sex sexual behaviors among male bachelors in rural China: evidence from a female shortage context.

    PubMed

    Yang, Xueyan; Attané, Isabelle; Li, Shuzhuo; Zhang, Qunlin

    2012-03-01

    Using data from a survey conducted in the rural areas of Anhui Province, this study adopted the crosstabs and logistic regression model to analyze the same-sex sexual behaviors of forced male bachelors and the determinants when compared with married men with same ages. The prevalence of same-sex sexual behaviors among the unmarried men was reported as 17.2%, significantly higher than 8.9% among married men with same ages, indicating that same-sex sexual behaviors could be as a compensation for the absence of female sexual partners to some extent for those marriage squeezed or forced male bachelors. Among all groups, the occurrence of unprotected sexual behaviors were reported above 60%, regardless of marital status and the genders of sexual partners; the scores obtained on knowledge of acquired immune deficiency syndrome (AIDS) and sexually transmitted diseases (STDs) among bachelors (AIDS knowledge = 2.85; STDs knowledge = 2.38) are much poorer than those of married men (AIDS knowledge = 3.45; STDs knowledge = 2.79), which might exert potential negative impacts on men's health. PMID:21816858

  4. The attraction of virgin female hide beetles (Dermestes maculatus) to cadavers by a combination of decomposition odour and male sex pheromones

    PubMed Central

    2012-01-01

    Introduction The hide beetle Dermestes maculatus (Coleoptera: Dermestidae) feeds as an adult and larva on decomposing animal remains and can also be found on human corpses. Therefore, forensic entomological questions with regard to when and how the first receptive females appear on carcasses are important, as the developmental stages of their larvae can be used to calculate the post-mortem interval. To date, we know that freshly emerged males respond to the cadaver odour of post-bloated carcasses (approximately 9 days after death at Tmean = 27°C), being attracted by benzyl butyrate. This component occurs at its highest concentration at this stage of decay. The aim of our study was to determine the principle of attraction of virgin females to the feeding and breeding substrate. For this purpose, we tested the response of these females to headspace samples of piglet cadavers and male sex pheromones [(Z9)-unsaturated fatty acid isopropyl esters] in a Y-olfactometer. Because we expected that such an odour combination is of importance for virgin female attraction, we tested the following two questions: 1) Are virgin female hide beetles attracted by a combination of cadaver odour and male sex pheromones? 2) During which decomposition stage do the first virgin females respond to cadaver odour when combined with male sex pheromones? Results We found that young virgin females were attracted to the cadaver by a combination of cadaver odour and male sex pheromones. Neither cadaver odour alone nor male sex pheromones alone was significantly more attractive than a solvent control. Our results also gave a weak indication that the first young virgin females respond as early as the post-bloating stage to its associated decomposition odour when combined with male sex pheromones. Conclusions Our results indicate that freshly emerged males possibly respond to cadaver odour and visit carcasses before virgin females. Being attracted to cadavers when male sex pheromone is perceived as well, virgin females can optimise their reproductive possibilities. PMID:22889339

  5. Polymorphic male color morphs visualized with steroids in monomorphic females: a tool for designing analysis of sex-limited trait inheritance.

    PubMed

    Olsson, Mats; Healey, Mo; Wilson, Mark; Tobler, Michael

    2012-02-15

    In diploid animals, males and females share most of the genome (except sex-specific elements, such as sex chromosome genes), yet despite sharing the underlying genes that hard-wire traits, males and females may differ in their phenotypes when traits are controlled by proximate mechanisms, such as hormones. In color polymorphic species where coloration is only expressed in one sex, the design of studies of the inheritance of color and coevolved morph-specific traits (e.g. territorial vs sneaker strategies, skewed energetic investment in territorial defense vs sperm production, etc.) is compromised as the expression of morph-coding genes is only visualized in one sex. Here, we circumvented this problem by first characterizing oxidative stress traits in both sexes and then using testosterone implants in females to expose their otherwise 'silent' coloration. Males of our model species are highly territorial and exhibit morph-specific levels of aggression, whereas females are non-territorial and display very low levels of aggression. Interestingly, reactive oxygen species levels were found to be morph specific regardless of sex, despite considerable differences in lifestyle. Males and females did differ remarkably, however, in superoxide levels depending on whether they sported a colored throat bib or not, a trait also used in male sexual signaling. Females with throat bibs had significantly lower levels of superoxide than females without a bib, which was not the case for males. PMID:22279063

  6. Context matters: the moderating role of bar context in the association between substance use during sex and condom use among male clients of female sex workers in Tijuana, Mexico.

    PubMed

    Pitpitan, Eileen V; Wagner, Karla D; Goodman-Meza, David; Semple, Shirley J; Chavarin, Claudia; Strathdee, Steffanie A; Patterson, Thomas L

    2013-10-01

    Tijuana is situated on Mexico's northern border with the U.S., where sex work is quasi-legal. Whereas previous work has focused on the risk behaviors of female sex workers (FSWs), less is known about the risk behaviors of their male clients. Further, research has not examined structural factors as moderators of the association between substance use and condom use, including the contexts in which sex takes place. The purpose of the current study is to examine whether having sex with FSWs in a bar moderates the link between alcohol intoxication during sex and condom use. We recruited 375 male clients of FSWs in Tijuana, Mexico from San Diego, California and Tijuana. Using computer assisted interviewing, we surveyed participants on their alcohol use, condom use, and physical contexts of sex with FSWs in the past 4 months. Results showed that more frequent intoxication during sex with FSWs is associated with more unprotected sex, but only among clients having sex with FSWs in a bar context. Results point to potential reasons for inconsistent condom use with FSWs in this context, including lower risk perceptions of sex with FSWs in bars. Future research should examine structural factors that underlie clients' risk behavior in bars in order to inform structural-level HIV prevention interventions. PMID:23640653

  7. Are Sex Drive and Hypersexuality Associated with Pedophilic Interest and Child Sexual Abuse in a Male Community Sample?

    PubMed Central

    Klein, Verena; Schmidt, Alexander F.; Turner, Daniel; Briken, Peer

    2015-01-01

    Although much is currently known about hypersexuality (in the form of excessive sexual behavior) among sexual offenders, the degree to which hypersexual behavior is linked to paraphilic and especially pedophilic interests in non-forensic populations has not been established. The purpose of the present study was to elucidate the associations between total sexual outlets (TSO) and other sex drive indicators, antisocial behavior, pedophilic interests, and sexual offending behavior in a large population-based community sample of males. The sample included 8,718 German men who participated in an online study. Hypersexual behavior as measured by self-reported TSO, self-reported sex drive, criminal history, and pedophilic interests were assessed. In moderated hierarchical logistic regression analyses self-reported contact sexual offending against children was linked to sexual fantasizing about children and antisociality. There was no association between aggregated sex drive, and sexual abusive behaviour in the multivariate analyses. In contrast, self-reported child pornography consumption was associated with sex drive, sexual fantasies involving children, and antisociality. Nevertheless, in clinical practice an assessment of criminal history and pedophilic interests in hypersexual individuals and vice versa hypersexuality in antisocial or pedophilic men should be considered as particularly antisociality and pedophilic interest are important predictors of sexual offending against prepubescent children. PMID:26147099

  8. Diagnosis of prolactinoma in two male-to-female transsexual subjects following high-dose cross-sex hormone therapy.

    PubMed

    Cunha, F S; Domenice, S; Câmara, V L; Sircili, M H P; Gooren, L J G; Mendonça, B B; Costa, E M F

    2015-08-01

    Male-to-female transsexual persons use oestrogens + antiandrogens to adapt their physical bodies to the female sex. Doses are usually somewhat higher than those used by hypogonadal women receiving oestrogen replacement. Particularly in cases of self-adminstration of cross-sex hormones, doses may be very high. Oestrogens are powerful stimulators of synthesis and release of prolactin and serum prolactin levels are usually somewhat increased following oestrogen treatment. Prolactinomas have been reported in male-to-female transsexual persons, both after use of high and conventional doses of oestrogens but remain rare events. We report two new cases of prolactinomas in male-to-female transsexual persons, one in a 41-year-old subject who had used nonsupervised high-dose oestrogen treatment since the age of 23 years and another one in a 42 year old who had initiated oestrogen treatment at the age of 17 years. Their serum prolactin levels were strongly increased, and the diagnosis of a pituitary tumour was confirmed by imaging techniques. Both cases responded well to treatment with cabergoline treatment whereupon serum prolactin normalised. Our two cases are added to the three cases of prolactinomas in the literature in persons who had used supraphysiological doses of oestrogens. PMID:25059808

  9. Evolution of sex determination systems with heterogametic males and females in silene.

    PubMed

    Slancarova, Veronika; Zdanska, Jana; Janousek, Bohuslav; Talianova, Martina; Zschach, Christian; Zluvova, Jitka; Siroky, Jiri; Kovacova, Viera; Blavet, Hana; Danihelka, Jiri; Oxelman, Bengt; Widmer, Alex; Vyskot, Boris

    2013-12-01

    The plant genus Silene has become a model for evolutionary studies of sex chromosomes and sex-determining mechanisms. A recent study performed in Silene colpophylla showed that dioecy and the sex chromosomes in this species evolved independently from those in Silene latifolia, the most widely studied dioecious Silene species. The results of this study show that the sex-determining system in Silene otites, a species related to S. colpophylla, is based on female heterogamety, a sex determination system that is unique among the Silene species studied to date. Our phylogenetic data support the placing of S. otites and S. colpophylla in the subsection Otites and the analysis of ancestral states suggests that the most recent common ancestor of S. otites and S. colpophylla was most probably dioecious. These observations imply that a switch from XX/XY sex determination to a ZZ/ZW system (or vice versa) occurred in the subsection Otites. This is the first report of two different types of heterogamety within one plant genus of this mostly nondioecious plant family. PMID:24299418

  10. Evaluation of organ doses and effective dose according to the ICRP Publication 110 reference male/female phantom and the modified ImPACT CT patient dosimetry.

    PubMed

    Kobayashi, Masanao; Asada, Yasuki; Matsubara, Kosuke; Matsunaga, Yuta; Kawaguchi, Ai; Katada, Kazuhiro; Toyama, Hiroshi; Koshida, Kichiro; Suzuki, Shouichi

    2014-01-01

    We modified the Imaging Performance Assessment of CT scanners (ImPACT) to evaluate the organ doses and the effective dose based on the International Commission on Radiological Protection (ICRP) Publication 110 reference male/female phantom with the Aquilion ONE ViSION Edition scanner. To select the new CT scanner, the measurement results of the CTDI100,c and CTDI100,p for the 160 (head) and the 320 (body) mm polymethylmethacrylate phantoms, respectively, were entered on the Excel worksheet. To compute the organ doses and effective dose of the ICRP reference male/female phantom, the conversion factors obtained by comparison between the organ doses of different types of phantom were applied. The organ doses and the effective dose were almost identical for the ICRP reference male/female and modified ImPACT. The results of this study showed that, with the dose assessment of the ImPACT, the difference in sex influences only testes and ovaries. Because the MIRD-5 phantom represents a partially hermaphrodite adult, the phantom has the dimensions of the male reference man including testes, ovaries, and uterus but no female breasts, whereas the ICRP male/female phantom includes whole-body male and female anatomies based on high-resolution anatomical datasets. The conversion factors can be used to estimate the doses of a male and a female accurately, and efficient dose assessment can be performed with the modified ImPACT. PMID:25207566

  11. Male-Killing Spiroplasma Induces Sex-Specific Cell Death via Host Apoptotic Pathway

    PubMed Central

    Harumoto, Toshiyuki; Anbutsu, Hisashi; Fukatsu, Takema

    2014-01-01

    Some symbiotic bacteria cause remarkable reproductive phenotypes like cytoplasmic incompatibility and male-killing in their host insects. Molecular and cellular mechanisms underlying these symbiont-induced reproductive pathologies are of great interest but poorly understood. In this study, Drosophila melanogaster and its native Spiroplasma symbiont strain MSRO were investigated as to how the host's molecular, cellular and morphogenetic pathways are involved in the symbiont-induced male-killing during embryogenesis. TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) staining, anti-cleaved-Caspase-3 antibody staining, and apoptosis-deficient mutant analysis unequivocally demonstrated that the host's apoptotic pathway is involved in Spiroplasma-induced male-specific embryonic cell death. Double-staining with TUNEL and an antibody recognizing epidermal marker showed that embryonic epithelium is the main target of Spiroplasma-induced male-specific apoptosis. Immunostaining with antibodies against markers of differentiated and precursor neural cells visualized severe neural defects specifically in Spiroplasma-infected male embryos as reported in previous studies. However, few TUNEL signals were detected in the degenerate nervous tissues of male embryos, and the Spiroplasma-induced neural defects in male embryos were not suppressed in an apoptosis-deficient host mutant. These results suggest the possibility that the apoptosis-dependent epidermal cell death and the apoptosis-independent neural malformation may represent different mechanisms underlying the Spiroplasma-induced male-killing. Despite the male-specific progressive embryonic abnormality, Spiroplasma titers remained almost constant throughout the observed stages of embryonic development and across male and female embryos. Strikingly, a few Spiroplasma-infected embryos exhibited gynandromorphism, wherein apoptotic cell death was restricted to male cells. These observations suggest that neither quantity nor proliferation of Spiroplasma cells but some Spiroplasma-derived factor(s) may be responsible for the expression of the male-killing phenotype. PMID:24550732

  12. Sexual competitiveness of Vienna 4\\/Tol-94 ‘genetic sexing’ sterile mediterranean fruit fly males in Israel

    Microsoft Academic Search

    Phillip W. Taylor; Allon Bear; Yoav Gazit; Yoram Rössler

    2001-01-01

    The sterile insect technique (SIT) is used as an environment-friendly means of suppressing Mediterranean fruit fly (Ceratitis capitata; ‘medfly’) populations in the Arava valley of Israel. The technique depends on released sterile males effectively wresting\\u000a the reproductive potential away from wild, fertile males. Studies carried out in other countries have indicated that sterile\\u000a males may sometimes be of inferior sexual

  13. Male Alcohol use and unprotected sex with non-regular partners: Evidence from wine shops in Chennai, India

    PubMed Central

    Sivaram, S.; Srikrishnan, A.K.; Latkin, C.; Iriondo-Perez, J.; Go, V.F.; Solomon, S.; Celentano, D.D.

    2008-01-01

    Background In India, heterosexual transmission accounts for approximately 80% of the spread of HIV, the virus that causes AIDS. Male alcohol use and its putative association with sexual risk are explored to inform HIV prevention interventions. Methods A survey of 1196 male patrons of wine shops or bars was conducted from August 2002 - Jan 2003 as part of an ongoing HIV prevention trial in Chennai city in south India. In the analysis, we explored associations between covariates related to sexual behavior and alcohol use and our outcome of unprotected sexual intercourse with non-regular partners among men Results Nearly half (43%) of the respondents reported any unprotected sex with non-regular partners and 24% had four or more recent sexual partners. Over 85% reported using alcohol at least 10 days a month (17% reported drinking everyday). During a typical drinking day, 49% reported consuming five or more drinks. Alcohol use before sex was reported by 89% of respondents. Unprotected sex with non-regular partners was significantly higher among unmarried men (OR=3.25), those who reported irregular income (OR=1.38), who used alcohol before sex (OR=1.75) and who had higher numbers of sexual partners (OR=14.5). Conclusions Our findings suggest that future HIV prevention interventions in India might consider discussing responsible alcohol use and its possible role in sexual risk. These interventions should particularly consider involving unmarried men and weigh the role of structural factors such as access to income in developing prevention messages. PMID:18187270

  14. Birth Order and Sibling Sex Ratio in a Population with High Fertility: Are Turkish Male to Female Transsexuals Different?

    PubMed

    Bozkurt, Ali; Bozkurt, Ozlem Hekim; Sonmez, Ipek

    2015-07-01

    Western studies have consistently found that androphilic (sexually attracted to men) male-to-female transsexuals have a later birth order and a relative excess of brothers compared with appropriate control participants. However, non-Western studies on birth order and sibling sex ratio in androphilic males (transsexual or non-transsexual) are rare. The objective of the study was to test the hypothesis that androphilic male-to-female transsexuals have a late birth order and a relative excess of brothers in a non-Western culture with a higher fertility rate. The participants were 60 androphilic male-to-female transsexuals and 61 male heterosexual controls. The transsexual participants had significantly more older brothers than the control participants, but the groups did not differ in their numbers of older sisters, younger brothers, or younger sisters. The foregoing pattern is usually referred to as the "fraternal birth order effect." Slater's and Berglin's Indexes both showed that the mean birth order of the control participants was very close to that expected from a random sample drawn from a demographically stable population whereas the mean birth order of the transsexual participants was later. A measure of sibship composition, brothers/all siblings, showed that the transsexual group had a higher proportion of male siblings compared with the control group. In conclusion, the present study found that Turkish androphilic male-to-female transsexuals show the same high fraternal birth order that has been found in comparable androphilic samples in Western Europe, North America, and the South Pacific, which suggests a common underlying biological causal mechanism. PMID:25351529

  15. Carotenoid-Based Ornaments of Female and Male American Goldfinches (Spinus tristis) Show Sex-Specific Correlations with Immune Function and Metabolic Rate

    Microsoft Academic Search

    Ryan J. Kelly; Troy G. Murphy; Keith A. Tarvin; Gary Burness

    2012-01-01

    Conspicuous ornamentation has been linked to immunological and physiological condition in males of many species. In species where both sexes are ornamented, it is unclear whether the signal content of ornaments differs between males and females. We examined the immunological and physiological correlates of carotenoid-based bill and plumage ornamentation in American goldfinches Spinus tristis, a species in which bright orange

  16. Localization of Male-Specifically Expressed MROS Genes of Silene latifolia by PCR on Flow-Sorted Sex Chromosomes and Autosomes

    Microsoft Academic Search

    Eduard Kejnovsky ´; Jan Vrana; Sachihiro Matsunaga; Premysl Soucek; Jaroslav Dolezel; Boris Vyskot

    The dioecious white campion Silene latifolia (syn. Melandrium album) has heteromorphic sex chromo- somes, XX in females and XY in males, that are larger than the autosomes and enable their separation by flow sorting. The group of MROS genes, the first male-specifically expressed genes in dioecious plants, was recently identified in S. latifolia. To localize the MROS genes, we used

  17. Effects of Atrazine on CYP19 Gene Expression and Aromatase Activity in Testes and on Plasma Sex Steroid Concentrations of Male African Clawed Frogs (Xenopus laevis)

    Microsoft Academic Search

    Markus Hecker; June-Woo Park; Margaret B. Murphy; Paul D. Jones; Keith R. Solomon; Glen Van Der Kraak

    2005-01-01

    Some investigators have suggested that the triazine herbicide atrazine can cause demasculinization of male amphibians via upregulation of the enzyme aromatase. Male adult African clawed frogs (Xenopus laevis) were exposed to three nominal concentrations of atrazine (1, 25, or 250mg atrazine\\/l) for 36 days, and testicular aromatase activity and CYP19 gene expression, as well as concentrations of the plasma sex

  18. Sex Differences in Political Communication: A Study of Female and Male State Legislators.

    ERIC Educational Resources Information Center

    Leenhouts, Thelma K.

    In an investigation of the communication similarities and differences between male and female legislators, the nine female representatives in the Michigan House of Representatives were matched with nine male representatives on four variables: political party, length of legislative service, district represented, and race. The representatives were…

  19. Familiarity and Sex Based Stereotypes on Instant Impressions of Male and Female Faculty

    ERIC Educational Resources Information Center

    Nadler, Joel T.; Berry, Seth A.; Stockdale, Margaret S.

    2013-01-01

    To address the stranger-to-stranger critique of stereotyping research, psychology students (n = 139) and law students (n = 58) rated photographs of familiar or unfamiliar male or female professors on competence. Results from Study 1 indicated that familiar male psychology faculty were rated as more competent than were familiar female faculty,…

  20. Sex Role Stereotyping for Household Chores by Aspiring and Incumbent Female and Male Public School Administrators.

    ERIC Educational Resources Information Center

    Pavan, Barbara Nelson

    A survey of male and female school administrators in Pennsylvania reveals that sexual division of labor in household activities differs little from stereotypical role expectations. A survey, mailed to 1,324 male and female administrative incumbents and aspirants, yielded 622 responses for a rate of 47 percent. The survey explored personal…

  1. tranny boyz: cyber community support in negotiating sex and gender mobility among female to male transsexuals

    Microsoft Academic Search

    DeAnn K. Gauthier; Nancy K. Chaudoir

    2004-01-01

    Female-to-male transsexuals (FTMs) are aware that manhood is a test that is separate from simple anatomical maleness. Failure to pass the test carries a penalty of exclusion from the desired rank as well as stigmatization as deviant for having attempted such a feat. Armed with this awareness, they are utilizing modern technology to form a community of virtual support, a

  2. Sex-Specific Genetic Structure and Social Organization in Central Asia: Insights from a Multi-Locus Study

    PubMed Central

    Ségurel, Laure; Martínez-Cruz, Begoña; Quintana-Murci, Lluis; Balaresque, Patricia; Georges, Myriam; Hegay, Tatiana; Aldashev, Almaz; Nasyrova, Firuza; Jobling, Mark A.; Heyer, Evelyne; Vitalis, Renaud

    2008-01-01

    In the last two decades, mitochondrial DNA (mtDNA) and the non-recombining portion of the Y chromosome (NRY) have been extensively used in order to measure the maternally and paternally inherited genetic structure of human populations, and to infer sex-specific demography and history. Most studies converge towards the notion that among populations, women are genetically less structured than men. This has been mainly explained by a higher migration rate of women, due to patrilocality, a tendency for men to stay in their birthplace while women move to their husband's house. Yet, since population differentiation depends upon the product of the effective number of individuals within each deme and the migration rate among demes, differences in male and female effective numbers and sex-biased dispersal have confounding effects on the comparison of genetic structure as measured by uniparentally inherited markers. In this study, we develop a new multi-locus approach to analyze jointly autosomal and X-linked markers in order to aid the understanding of sex-specific contributions to population differentiation. We show that in patrilineal herder groups of Central Asia, in contrast to bilineal agriculturalists, the effective number of women is higher than that of men. We interpret this result, which could not be obtained by the analysis of mtDNA and NRY alone, as the consequence of the social organization of patrilineal populations, in which genetically related men (but not women) tend to cluster together. This study suggests that differences in sex-specific migration rates may not be the only cause of contrasting male and female differentiation in humans, and that differences in effective numbers do matter. PMID:18818760

  3. DNA is organized into 46 chromosomes including sex chromosomes, 3D animation with no audioSite: DNA Interactive (www.dnai.org)

    NSDL National Science Digital Library

    2008-10-06

    The millions of bases, which make up the human genome are organized into structures called chromosomes. These are arranged into 22 matching pairs plus 1 pair of sex chromosomes consisting of 2 X's in women and an X and a Y in men. So humans have a total of 46 chromosomes in each cell, known collectively as a karyotype. This set of chromosomes has a Y, so it must belong to a male.

  4. Understanding same-sex male and female partners' restrained eating in the context of their relationships.

    PubMed

    Bailey, Lindzee; Markey, Charlotte N; Markey, Patrick M; August, Kristin J; Nave, Christopher S

    2015-06-01

    This study examined weight status and dietary restraint among same-sex couples using Actor-Partner Interdependence Models. Body mass indices and restrained eating behaviors (i.e., cognitive dietary restraint, uncontrolled eating, and emotional eating) were assessed for members of 144 same-sex couples (72 lesbian and 72 gay couples; mean age?=?33.74?years, standard deviation?=?11.27 years). Results indicated that both men and women who were relatively heavy and who had relatively thin partners were at particular risk of engaging in restrained eating. These findings extend our understanding of partner comparison processes within the context of same-sex relationships in determining men and women's eating behaviors. PMID:26032798

  5. HIV Risk Behaviors Among a Sample of Heterosexually Identified Men who Occasionally Have Sex with Another Male and\\/or a Transwoman

    Microsoft Academic Search

    Cathy J. Reback; Sherry Larkins

    2011-01-01

    Discordance between sexual identity and sexual behavior is not new; however, little is known about the HIV risk behaviors of heterosexually identified men who have occasional sex with a male and\\/or a male-to-female transgender woman. Open-ended qualitative interviews were conducted with 31 heterosexually identified men who reported at least one sexual encounter with a male and\\/or a transwoman in the

  6. Females prefer to associate with males with longer intromittent organs in mosquitofish

    PubMed Central

    Kahn, Andrew T.; Mautz, Brian; Jennions, Michael D.

    2010-01-01

    Sexual selection is a major force behind the rapid evolution of male genital morphology among species. Most within-species studies have focused on sexual selection on male genital traits owing to events during or after copulation that increase a male's share of paternity. Very little attention has been given to whether genitalia are visual signals that cause males to vary in their attractiveness to females and are therefore under pre-copulatory sexual selection. Here we show that, on average, female eastern mosquitofish Gambusia holbrooki spent more time in association with males who received only a slight reduction in the length of the intromittent organ (‘gonopodium’) than males that received a greater reduction. This preference was, however, only expressed when females chose between two large males; for small males, there was no effect of genital size on female association time. PMID:19755529

  7. Assessment of Deviant Arousal in Adult Male Sex Offenders with Developmental Disabilities

    ERIC Educational Resources Information Center

    Reyes, Jorge R.; Vollmer, Timothy R.; Sloman, Kimberly N.; Hall, Astrid; Reed, Robert; Jansen, Greg; Carr, Sam; Jackson, Kevin; Stoutimore, Michael

    2006-01-01

    Ten individuals, residing in a treatment facility specializing in the rehabilitation of sex offenders with developmental disabilities, participated in an arousal assessment involving the use of the penile plethysmograph. The arousal assessments involved measuring change in penile circumference to various categories of stimuli both appropriate…

  8. Sex hormone receptors are expressed in identified respiratory motoneurons in male and female rats

    Microsoft Academic Search

    M. Behan; C. F. Thomas

    2005-01-01

    Sex hormones including estrogen, progesterone and testosterone can influence breathing. However, it is not clear whether such hormones exert their effects directly on respiratory motoneurons. We used immunocytochemistry to demonstrate that estrogen receptor ?, estrogen receptor ? and androgen receptor are localized in respiratory motor neurons. Motoneurons in the hypoglossal (XII) and the phrenic nuclei were retrogradely labeled from the

  9. Boredom Proneness, Social Connectedness, and Sexual Addiction among Men Who Have Sex with Male Internet Users

    ERIC Educational Resources Information Center

    Chaney, Michael P.; Blalock, Andrew C.

    2006-01-01

    The authors collected surveys from 517 men who have sex with men (MSM) recruited from Internet chat rooms to examine the relationships among boredom, social connectedness, and sexual addiction. The results provide addictions professionals psychosocial factors to assess when working with sexually addicted MSM. (Contains 3 tables.)

  10. Same-sized fish groups increase aggressive interaction of sex-reversed males Nile tilapia GIFT strain

    Microsoft Academic Search

    Camila Nomura Pereira Boscolo; Rosana Nogueira Morais; Eliane Gonçalves-de-Freitas

    Animals with similar fighting ability can fight harder and longer than animals in asymmetric contests. Thus, the selection of fish by size similarity in husbandry might increase aggressive interactions, and lead to social instability in socially organized fish. We tested the hypothesis that grouping same-sized animals increases aggressive interactions between males of Genetic Improved Farmed Tilapia (GIFT). This could destabilize

  11. Behavior of processionary males ( Thaumetopoea pityocampa ) induced by sex pheromone and analogs in a wind tunnel

    Microsoft Academic Search

    Carmen Quero; Francisco Camps; Angel Guerrero

    1995-01-01

    The behavioral response of processionary males (Thaumetopoea pityocampa) to the natural pheromone (Z)-13-hexadecen-11-ynyl acetate (1) and structurally related analogs in a wind tunnel is presented. Stereomerically pureZ-1 and a mixture with theE isomer in 80:20 ratio elicited similar attraction responses at 1 µg and higher. The activity was dose-dependent, being optimum at 1 µg with 90% and 80% of males

  12. Sex workers in Calcutta organize themselves to become agents for change.

    PubMed

    Bandyopadhyay, N; Banerjee, B

    1999-01-01

    A small-scale intervention program for sex workers employed in brothels in Calcutta, India, grew into a powerful association of men and women fighting for their rights. In 1992, 4000 brothel-based sex workers joined a program with the All India Institute of Hygiene and Public Health (AIIH&PH), as well as with government and nongovernmental organizations (NGOs). The Sonagachi Sexually Transmitted Disease (STD)/HIV Intervention Program (SHIP) was designed to control and prevent HIV infections and STDs among the sex workers through various health services, condom promotion and information, education and communication programs and activities. To ensure sustainability of the program in the target community, AII&PH turned over the SHIP to a registered organization constituted by workers of SHIP, sex workers forums and representatives from government and NGOs. PMID:12295568

  13. “Talking the talk, walking the walk: Social network norms, communication patterns, and condom use among the male partners of female sex workers in La Romana, Dominican Republic”

    PubMed Central

    Barrington, Clare; Latkin, Carl; Sweat, Michael; Moreno, Luis; Ellen, Jonathan; Kerrigan, Deanna

    2009-01-01

    Male partners of female sex workers are rarely targeted by HIV prevention interventions in the commercial sex industry, despite recognition of their central role and power in condom use negotiation. Social networks offer a naturally existing social structure to increase male participation in preventing HIV. The purpose of this study was to explore the relationship between social network norms and condom use among male partners of female sex workers in La Romana, Dominican Republic. Male partners (n=318) were recruited from 36 sex establishments to participate in a personal network survey. Measures of social network norms included 1) perceived condom use by male social network members and 2) encouragement to use condoms from social network members. Other social network characteristics included composition, density, social support, and communication. The primary behavioral outcome was consistent condom use by male partners with their most recent female sex worker partner during the last 3 months. In general, men reported small, dense networks with high levels of communication about condoms and consistent condom use. Multivariate logistic regression revealed consistent condom use was significantly more likely among male partners who perceived that some or all of their male social network members used condoms consistently. Perceived condom use was, in turn, significantly associated with dense networks, expressing dislike for condoms, and encouragement to use condoms from social network members. Findings suggest that the tight social networks of male partners may help to explain the high level of condom use and could provide an entry point for HIV prevention efforts with men. Such efforts should tap into existing social dynamics and patterns of communication to promote pro-condom norms and reduce HIV-related vulnerability among men and their sexual partners. PMID:19356834

  14. Determinants of parental care and offspring survival during the post-fledging period: males care more in a species with partially reversed sex roles.

    PubMed

    Gow, Elizabeth A; Wiebe, Karen L

    2014-05-01

    Sexual conflict is magnified during the post-fledging period of birds when the sexes face different trade-offs between continuing parental care or investing in self maintenance or other mating opportunities. Species with reversed sex roles provide a unique opportunity to study the relationship between mating systems and investment in parental care. Here, we provide the first detailed study of the length of care by males versus females (n = 24 pairs) during the post-fledging period, assessing factors that may promote care within and between the sexes. In the northern flicker Colaptes auratus, a species with partly reversed sex roles, males cared longer than females (average 16 versus 12 days, respectively). Overall, 36% of females but no males deserted the brood prior to fledgling independence. Parents that provisioned nestlings at a high rate also spent more days feeding fledglings. Among males, age and nestling feeding rates were positively associated with the length of care. Among females, a low level of feather corticosterone (CORTf) was associated with a longer length of care. About 45% of fledglings died within the first week, but fledglings with intermediate body mass had the highest survival suggesting stabilizing selection on mass. Fledgling survival was also higher in individuals with larger broods and lower levels of CORTf. We demonstrate that because females can be polyandrous they often desert the brood before males, and that the sexes respond to different cues relating to their energy balance when deciding the length of care given to their offspring. PMID:24496554

  15. Pseudosynapsis and Decreased Stringency of Meiotic Repair Pathway Choice on the Hemizygous Sex Chromosome of Caenorhabditis elegans Males

    PubMed Central

    Checchi, Paula M.; Lawrence, Katherine S.; Van, Mike V.; Larson, Braden J.; Engebrecht, JoAnne

    2014-01-01

    During meiosis, accurate chromosome segregation relies on homology to mediate chromosome pairing, synapsis, and crossover recombination. Crossovers are dependent upon formation and repair of double-strand breaks (DSBs) by homologous recombination (HR). In males of many species, sex chromosomes are largely hemizygous, yet DSBs are induced along nonhomologous regions. Here we analyzed the genetic requirements for meiotic DSB repair on the completely hemizygous X chromosome of Caenorhabditis elegans males. Our data reveal that the kinetics of DSB formation, chromosome pairing, and synapsis are tightly linked in the male germ line. Moreover, DSB induction on the X is concomitant with a brief period of pseudosynapsis that may allow X sister chromatids to masquerade as homologs. Consistent with this, neither meiotic kleisins nor the SMC-5/6 complex are essential for DSB repair on the X. Furthermore, early processing of X DSBs is dependent on the CtIP/Sae2 homolog COM-1, suggesting that as with paired chromosomes, HR is the preferred pathway. In contrast, the X chromosome is refractory to feedback mechanisms that ensure crossover formation on autosomes. Surprisingly, neither RAD-54 nor BRC-2 are essential for DSB repair on the X, suggesting that unlike autosomes, the X is competent for repair in the absence of HR. When both RAD-54 and the structure-specific nuclease XPF-1 are abrogated, X DSBs persist, suggesting that single-strand annealing is engaged in the absence of HR. Our findings indicate that alteration in sister chromatid interactions and flexibility in DSB repair pathway choice accommodate hemizygosity on sex chromosomes. PMID:24939994

  16. RNAi-Mediated Gene Silencing in a Gonad Organ Culture to Study Sex Determination Mechanisms in Sea Turtle

    PubMed Central

    Sifuentes-Romero, Itzel; Merchant-Larios, Horacio; Milton, Sarah L.; Moreno-Mendoza, Norma; Díaz-Hernández, Verónica; García-Gasca, Alejandra

    2013-01-01

    The autosomal Sry-related gene, Sox9, encodes a transcription factor, which performs an important role in testis differentiation in mammals. In several reptiles, Sox9 is differentially expressed in gonads, showing a significant upregulation during the thermo-sensitive period (TSP) at the male-promoting temperature, consistent with the idea that SOX9 plays a central role in the male pathway. However, in spite of numerous studies, it remains unclear how SOX9 functions during this event. In the present work, we developed an RNAi-based method for silencing Sox9 in an in vitro gonad culture system for the sea turtle, Lepidochelys olivacea. Gonads were dissected as soon as the embryos entered the TSP and were maintained in organ culture. Transfection of siRNA resulted in the decrease of both Sox9 mRNA and protein. Furthermore, we found coordinated expression patterns for Sox9 and the anti-Müllerian hormone gene, Amh, suggesting that SOX9 could directly or indirectly regulate Amh expression, as it occurs in mammals. These results demonstrate an in vitro method to knockdown endogenous genes in gonads from a sea turtle, which represents a novel approach to investigate the roles of important genes involved in sex determination or differentiation pathways in species with temperature-dependent sex determination. PMID:24705165

  17. The costs of being male: are there sex-specific effects of uniparental mitochondrial inheritance?

    PubMed

    Beekman, Madeleine; Dowling, Damian K; Aanen, Duur K

    2014-07-01

    Eukaryotic cells typically contain numerous mitochondria, each with multiple copies of their own genome, the mtDNA. Uniparental transmission of mitochondria, usually via the mother, prevents the mixing of mtDNA from different individuals. While on the one hand, this should resolve the potential for selection for fast-replicating mtDNA variants that reduce organismal fitness, maternal inheritance will, in theory, come with another set of problems that are specifically relevant to males. Maternal inheritance implies that the mitochondrial genome is never transmitted through males, and thus selection can target only the mtDNA sequence when carried by females. A consequence is that mtDNA mutations that confer male-biased phenotypic expression will be prone to evade selection, and accumulate. Here, we review the evidence from the ecological, evolutionary and medical literature for male specificity of mtDNA mutations affecting fertility, health and ageing. While such effects have been discovered experimentally in the laboratory, their relevance to natural populations--including the human population--remains unclear. We suggest that the existence of male expression-biased mtDNA mutations is likely to be a broad phenomenon, but that these mutations remain cryptic owing to the presence of counter-adapted nuclear compensatory modifier mutations, which offset their deleterious effects. PMID:24864311

  18. The costs of being male: are there sex-specific effects of uniparental mitochondrial inheritance?

    PubMed Central

    Beekman, Madeleine; Dowling, Damian K.; Aanen, Duur K.

    2014-01-01

    Eukaryotic cells typically contain numerous mitochondria, each with multiple copies of their own genome, the mtDNA. Uniparental transmission of mitochondria, usually via the mother, prevents the mixing of mtDNA from different individuals. While on the one hand, this should resolve the potential for selection for fast-replicating mtDNA variants that reduce organismal fitness, maternal inheritance will, in theory, come with another set of problems that are specifically relevant to males. Maternal inheritance implies that the mitochondrial genome is never transmitted through males, and thus selection can target only the mtDNA sequence when carried by females. A consequence is that mtDNA mutations that confer male-biased phenotypic expression will be prone to evade selection, and accumulate. Here, we review the evidence from the ecological, evolutionary and medical literature for male specificity of mtDNA mutations affecting fertility, health and ageing. While such effects have been discovered experimentally in the laboratory, their relevance to natural populations—including the human population—remains unclear. We suggest that the existence of male expression-biased mtDNA mutations is likely to be a broad phenomenon, but that these mutations remain cryptic owing to the presence of counter-adapted nuclear compensatory modifier mutations, which offset their deleterious effects. PMID:24864311

  19. Nestsite selection by male loons leads to sex-biased site familiarity.

    PubMed

    Piper, Walter H; Walcott, Charles; Mager, John N; Spilker, Frank J

    2008-03-01

    1. The concept that animals benefit from gaining familiarity with physical spaces is widespread among ecologists and constitutes a theoretical pillar in studies of territory defence, philopatry and habitat selection. Yet proximate causes and fitness benefits of site familiarity are poorly known. 2. We used data from marked common loons Gavia immer breeding on 98 territories over 14 years to investigate the 'win-stay, lose-switch rule' for nestsite placement (if eggs hatch, reuse nestsite; if predator takes eggs, move nestsite). Males controlled nest placement in this species: pairs used the rule if both members remained the same from the previous nesting attempt or if only the male remained the same but not if only the female remained the same. 3. By means of the nesting rule, male common loons benefited from site familiarity, increasing nesting success by 41% between their first and third years on a territory. In contrast, females exhibited no increase in nesting success with increased territorial tenure. 4. Owing to site familiarity, a male loon competing for a breeding territory faces a considerable 'familiarity deficit' compared with the male breeder already established there. The familiarity deficit probably explains why resident animals often fight hard to retain familiar territories, when challenged, and why animals of many species tend to remain on familiar territories rather than moving when territories of higher intrinsic quality become available nearby. PMID:17976165

  20. Preferred and actual relative height among homosexual male partners vary with preferred dominance and sex role.

    PubMed

    Valentova, Jaroslava Varella; Stulp, Gert; T?ebický, Vít; Havlí?ek, Jan

    2014-01-01

    Previous research has shown repeatedly that human stature influences mate preferences and mate choice in heterosexuals. In general, it has been shown that tall men and average height women are most preferred by the opposite sex, and that both sexes prefer to be in a relationship where the man is taller than the woman. However, little is known about such partner preferences in homosexual individuals. Based on an online survey of a large sample of non-heterosexual men (N = 541), we found that the majority of men prefer a partner slightly taller than themselves. However, these preferences were dependent on the participant's own height, such that taller men preferred shorter partners, whereas shorter men preferred taller partners. We also examined whether height preferences predicted the preference for dominance and the adoption of particular sexual roles within a couple. Although a large proportion of men preferred to be in an egalitarian relationship with respect to preferred dominance (although not with respect to preferred sexual role), men that preferred a more dominant and more "active" sexual role preferred shorter partners, whereas those that preferred a more submissive and more "passive" sexual role preferred taller partners. Our results indicate that preferences for relative height in homosexual men are modulated by own height, preferred dominance and sex role, and do not simply resemble those of heterosexual women or men. PMID:24466136

  1. Stumbling into sexual crime: the passive perpetrator in accounts by male internet sex offenders.

    PubMed

    Winder, Belinda; Gough, Brendan; Seymour-Smith, Sarah

    2015-01-01

    Public reactions to internet child offending remain ambivalent in that, while there is vocal condemnation of contact child sex offending, there is less indignation about internet child abuse. This is potentially due to a lack of recognition of this type of offence as sexual offending per se. This ambiguity is reflected by internet sex offenders themselves in their verbalizations of their offending. This article presents a qualitative analysis of the accounts offered by seven individuals convicted of internet-based sexual offences involving the downloading and viewing of images of children. In particular, this article presents an analysis of the explanations of offenders for the commencement of internet activity and the progression to more illicit online materials. The data were collected through semi-structured interviews and analyzed using discursive methods, paying close attention to language use and function. The analysis documented the practices that internet child abusers employed in order to manage their identities, distance themselves from the label of sex offender, and/or reduce their personal agency and accountability. Implications of this analysis are discussed with reference to the current minimization of the downloading of sexually explicit images of children as a sexual crime per se by the public and offenders alike and the risk assessment and treatment of individuals convicted of these offences. PMID:24917484

  2. Population- and Sex-Biased Gene Expression in the Excretion Organs of Drosophila melanogaster

    PubMed Central

    Huylmans, Ann Kathrin; Parsch, John

    2014-01-01

    Within species, levels of gene expression typically vary greatly between tissues, sexes, individuals, and populations. To investigate gene expression variation between sexes and populations in a single somatic tissue, we performed a quantitative analysis of the Malpighian tubule transcriptome in adult males and females of Drosophila melanogaster derived from two distinct populations (one from sub-Saharan Africa and one from northern Europe). We identified 2308 genes that differed in expression between the sexes and 2474 genes that differed in expression between populations at a false discovery rate of 5%. We also identified more than 1000 genes that showed a sex-by-population interaction in their expression. The genes that differed in expression between sexes showed enrichment for a wide variety of functions, although only 55% of them overlapped with sex-biased genes identified in whole-fly studies. The genes expressed differentially between populations included several that were previously implicated in adaptive regulatory evolution, an excess of cytochrome P450 genes, and many genes that were not detected in previous studies of whole flies. Our results demonstrate that there is abundant intraspecific gene expression variation within in a single, somatic tissue and uncover new candidates for adaptive regulatory evolution between populations. PMID:25246242

  3. Male hosts are responsible for the transmission of a trophically transmitted parasite, Pterygodermatites peromysci, to the intermediate host in the absence of sex-biased infection.

    PubMed

    Luong, Lien T; Grear, Daniel A; Hudson, Peter J

    2009-09-01

    Field studies have identified that male-biased infection can lead to increased rates of transmission, so we examined the relative importance of host sex on the transmission of a trophically transmitted parasite (Pterygodermatites peromysci) where there is no sex-biased infection. We experimentally reduced infection levels in either male or female white-footed mice (Peromyscus leucopus) on independent trapping grids with an anthelmintic and recorded subsequent infection levels in the intermediate host, the camel cricket (Ceuthophilus pallidipes). We found that anthelmintic treatment significantly reduced the prevalence of infection among crickets in both treatment groups compared with the control, and at a rate proportional to the number of mice de-wormed, indicating prevalence was not affected by the sex of the shedding definitive host. In contrast, parasite abundance in crickets was higher on the grids where females were treated compared with the grids where males were treated. These findings indicate that male hosts contribute disproportionately more infective stages to the environment and may therefore be responsible for the majority of parasite transmission even when there is no discernable sex-biased infection. We also investigated whether variation in nematode length between male and female hosts could account for this male-biased infectivity, but found no evidence to support that hypothesis. PMID:19397911

  4. [New sex pheromone isolated from the abdominal glands of male newt, Cynops pyrrhogaster].

    PubMed

    Toyoda, F; Hayashi, H; Ohmiya, Y; Tanaka, S; Mochida, H; Matsuda, K; Kikuyama, S

    1995-01-01

    Sodefrin, a novel decapeptide which attracts female newts, Cynops pyrrhogaster was isolated from the abdominal gland of the male of the same species. Synthetic sodefrin was tested for its activity with sexually active females and males and sexually inert females. It attracted only sexually active females. The effect of sodefrin was blocked by a bilateral nostril plugging with cotton balls soaked in melted vaseline. Immunoelectronmicroscopic study using antiserum against sodefrin revealed that sodefrin was located mainly in the secretory granules in the epithelial cells of the abdominal gland of the cloaca. PMID:8763038

  5. Organizations and Inequality: Sources of Earnings Differences Between Male and Female Faculty.

    ERIC Educational Resources Information Center

    Tolbert, Pamela S.

    1986-01-01

    Examines the relationships between organizational characteristics and earnings differences between male and female faculty. Results show that the greater an organization's power and autonomy, the more likely it will exercise discriminatory preferences by hiring more males and paying them higher salaries than females. (Author/JDH)

  6. The Destruction of the Young Black Male: The Impact of Popular Culture and Organized Sports.

    ERIC Educational Resources Information Center

    Gaston, John C.

    1986-01-01

    Argues that the negative aspects of popular culture and organized sports in American society contribute to the economic, psychological, and social destruction of the Black male. The media nurtures unrealistic fantasies in young Black males, preventing them from acquiring the education and skills necessary to participate in the mainstream. (ETS)

  7. Effects of steroid sex hormones on chick embryo gonads in organ culture, with special reference to hormonal control

    E-print Network

    Paris-Sud XI, Université de

    Effects of steroid sex hormones on chick embryo gonads in organ culture, with special reference to hormonal control of gonadal sex differentiation J. JORDANOV Pavlina ANGELOVA lnstitute of Morpho. At the initial stages of sex differentiation (7.5 and 8.5 days of incubation chick embryo gonads were treated

  8. Prenatal exposure to a low-frequency electromagnetic field demasculinizes adult scent marking behavior and increases accessory sex organ weights in rats

    SciTech Connect

    McGivern, R.F.; Sokol, R.Z.; Adey, W.R.

    1990-01-01

    Pregnant Sprague-Dawley dams were exposed to a low-level, low-frequency pulsed electromagnetic (EM) field (15 Hz, 0.3 msec duration, peak intensity 8 gauss) for 15 min twice a day from day 15 through day 20 of gestation, a period in development that is critical for sexual differentiation of the male rat brain. No differences in litter size, number of stillborns, or body weight were observed in offspring from field-exposed dams. At 120 days of age, field-exposed male offspring exhibited significantly less scent marking behavior than controls. Accessory sex organ weights, including epididymis, seminal vesicles, and prostate, were significantly higher in field-exposed subjects at this age. However, circulating levels of testosterone, luteinizing hormone, and follicle-stimulating hormone, as well as epididymal sperm counts, were normal. These data indicate that brief, intermittent exposure to low-frequency EM fields during the critical prenatal period for neurobehavioral sex differentiation can demasculinize male scent marking behavior and increase accessory sex organ weights in adulthood.

  9. Effects of Tribulus terrestris on endocrine sensitive organs in male and female Wistar rats

    Microsoft Academic Search

    Anderson J. Martino-Andrade; Rosana N. Morais; Katherinne M. Spercoski; Stefani C. Rossi; Marina F. Vechi; Munisa Golin; Natália F. Lombardi; Cláudio S. Greca; Paulo R. Dalsenter

    2010-01-01

    Aim of the studyInvestigate the possible effects of Tribulus terrestris (TT) on endocrine sensitive organs in intact and castrated male rats as well as in a post-menopausal rat model using ovariectomized females.

  10. Age, sex, reproduction, and spatial organization of lynxes colonizing northeastern Minnesota

    USGS Publications Warehouse

    Mech, L.D.

    1980-01-01

    From 1972 through 1978, lynxes (Felis lynx) emigrating from Canada were studied in northeastern Minnesota. Fourteen individuals were radio-tracked, 8 wefe ear-tagged, and 49 carcasses were examined. Sex ratios of the samples were equal during the first years of the study, but females predominated later. At least half of the radiotagged lynxes were killed by humans; no natural mortality was detected. Home range sizes ranged from 51 to 122 km2 for females and 145 to 243 km2 for males, up to 10 times the sizes of those reported by other workers. Ranges of females tended to overlap. Males and females appeared to be segregated in the population.

  11. Disorder of sex development (XX male, SRY negative) in a French bulldog

    PubMed Central

    Silversides, David W.; Benoit, Jean-Marc; Collard, Fabien; Gilson, Catherine

    2011-01-01

    A female French bulldog was presented with an enlarged clitoris. Abdominal surgery revealed a normal uterus and gonads resembling testes. Histologically, the gonads contained seminiferous tubules. The karyotype was XX, and the SRY gene was not detected. A diagnosis of XX male, SRY negative disorder of sexual development was made. PMID:22131587

  12. Annual cycle of plasma luteinizing hormone and sex hormones in male and female mallards (Anas platyrhynchos)

    USGS Publications Warehouse

    Donham, R.S.

    1979-01-01

    Comparisons between 'wild'and 'game farm' mallards (Anas platyrhynchos) were made to assess the differences in the temporal changes of plasma hormones. Seasonal variation in the levels of immunoreactive luteinizing hormone (LH), testosterone, 5 -dihydrotestosterone (DHT), estrone, estradiol-17i?? and progesterone were measured in male and female mallards. In all birds there was a vernal increase in the concentrations of LH and testosterone in plasma which were correlated with the development of the testes and ovaries prior to and during the nesting season. The concentrations of estrogens in the plasma of the females were, in general, slightly higher during the nesting season but were much lower than the levels of testosterone. The highest levels of LH and testosterone in the females coincided precisely with the period of egg laying which occurred approximately one month earlier in game farm females than in wild females. The concentrations of LH and testosterone in the plasma of females decreased rapidly during incubation. In wild males, the decline in levels of these hormones temporally coincided with that of females. In contrast, plasma levels of LH and testosterone of males of the game farm stock remained elevated after the beginning of incubation in females to which they were paired. On the basis of these results and an examination of the literature, it appears that domestication results in: 1) increased reproductive potential through earlier initiation of nesting and by delay of the termination of reproduction until later in the summer; and 2) a decrease in the synchronization of the hormonal events supporting reproduction between the male and female of a pair. Testicular weights and plasma levels of testosterone become higher in game farm and domestic males than in the wild stock but levels of LH are similar.

  13. Recombination Between Homologous Autosomes in Medfly ( Ceratitis Capitata ) Males: Type1 Recombination and the Implications for the Stability of Genetic Sexing Strains

    Microsoft Academic Search

    G. Franz

    2002-01-01

    The sterile insect technique (SIT) is an environmentally safe technology to control insect pests. To improve this technology, genetic sexing strains (GSS) have been developed for the Mediterranean fruit fly, Ceratitis capitata. Such strains are based on Y-autosome translocations linking a selectable marker to the male sex and their long-term stability, especially under large-scale mass rearing conditions, is threatened by

  14. Molecular cloning and quantitative expression of sexually dimorphic markers Dmrt1 and Foxl2 during female-to-male sex change in Epinephelus merra

    Microsoft Academic Search

    Mohammad Ashraful Alam; Yasuhisa Kobayashi; Ryo Horiguchi; Toshiaki Hirai; Masaru Nakamura

    2008-01-01

    The honeycomb grouper (Epinephelus merra) is one of the smallest members of the Serranidae family and is often used to study protogynous sex change. To determine the role of the male-determining gene Dmrt1 and the ovarian-specific gene Foxl2 in sex change, we cloned these two markers from E. merra gonads by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification

  15. Number of casual male sexual partners and associated factors among men who have sex with men: Results from the National HIV Behavioral Surveillance system

    Microsoft Academic Search

    Eli S Rosenberg; Patrick S Sullivan; Elizabeth A DiNenno; Laura F Salazar; Travis H Sanchez

    2011-01-01

    Background  In 2006, the majority of new HIV infections were in MSM. We sought to describe numbers of casual sex partners among US MSM.\\u000a \\u000a \\u000a \\u000a Methods  Data are from the first MSM cycle of the National HIV Behavioral Surveillance system, conducted from 2003 to 2005. Relationships\\u000a between number of casual male sex partners within the previous year and demographic information, self-reported HIV status,

  16. HIV prevalence and related risk factors among male sex workers in Shenzhen, China: results from a time–location sampling survey

    Microsoft Academic Search

    Wen-De Cai; Jin Zhao; Jin-Kou Zhao; H. F. Raymond; Yu-Ji Feng; Jie Liu; Willi McFarland; Yong-Xia Gan; Zheng-Rong Yang; Yan Zhang; Jing-Guang Tan; Xiao-Rong Wang; Ming-Liang He; Jin-Quan Cheng; Lin Chen

    2009-01-01

    BackgroundHIV transmission among men who have sex with men has recently become a major concern in China. Little is known, however, about HIV transmission among male sex workers (MSW). This study aimed to investigate HIV infection prevalence and risk factors among MSW in Shenzhen, China.Materials and methodsFollowing formative research, a cross-sectional study was conducted using time–location sampling among MSW in

  17. Inherited human sex reversal due to impaired nucleocytoplasmic trafficking of SRY defines a male transcriptional threshold

    PubMed Central

    Chen, Yen-Shan; Racca, Joseph D.; Phillips, Nelson B.; Weiss, Michael A.

    2013-01-01

    Human testis determination is initiated by SRY (sex determining region on Y chromosome). Mutations in SRY cause gonadal dysgenesis with female somatic phenotype. Two subtle variants (V60L and I90M in the high-mobility group box) define inherited alleles shared by an XY sterile daughter and fertile father. Whereas specific DNA binding and bending are unaffected in a rat embryonic pre-Sertoli cell line, the variants exhibited selective defects in nucleocytoplasmic shuttling due to impaired nuclear import (V60L; mediated by Exportin-4) or export (I90M; mediated by chromosome region maintenance 1). Decreased shuttling limits nuclear accumulation of phosphorylated (activated) SRY, in turn reducing occupancy of DNA sites regulating Sertoli-cell differentiation [the testis-specific SRY-box 9 (Sox9) enhancer]. Despite distinct patterns of biochemical and cell-biological perturbations, V60L and I90M each attenuated Sox9 expression in transient transfection assays by twofold. Such attenuation was also observed in studies of V60A, a clinical variant associated with ovotestes and hence ambiguity between divergent cell fates. This shared twofold threshold is reminiscent of autosomal syndromes of transcription-factor haploinsufficiency, including XY sex reversal associated with mutations in SOX9. Our results demonstrate that nucleocytoplasmic shuttling of SRY is necessary for robust initiation of testicular development. Although also characteristic of ungulate orthologs, such shuttling is not conserved among rodents wherein impaired nuclear export of the high-mobility group box and import-dependent phosphorylation are compensated by a microsatellite-associated transcriptional activation domain. Human sex reversal due to subtle defects in the nucleocytoplasmic shuttling of SRY suggests that its transcriptional activity lies near the edge of developmental ambiguity. PMID:24003159

  18. Individual differences in cognitive abilities and brain organization: I. Sex and handedness differences in ability

    Microsoft Academic Search

    Richard A. Harshman; Elizabeth Hampson; Sheri A. Berenbaum

    1983-01-01

    Analyzed data on cognitive abilities from 3 samples of normal Ss: (1) 195 undergraduates, (2) 215 18–30 yr old newly married couples, and (3) 122 pairs of monozygotic and dizygotic twins (aged 12–38 yrs). Findings reveal a common Sex by Handedness by Reasoning-Ability interaction: For Ss with above-median reasoning ability, spatial scores of left-handed males were reduced but those of

  19. "Nobody's ever going to make a fag pretty woman": stigma awareness and the putative effects of stigma among a sample of Canadian male sex workers.

    PubMed

    Morrison, Todd G; Whitehead, Bruce W

    2007-01-01

    The purpose of this study was to examine male sex workers' awareness of the social stigma surrounding involvement in the sex industry and the possible effects of that stigma. Personal interviews were conducted with 21 men (9 independent escorts who advertised via the Internet and 12 escorts/erotic masseurs who were on contract with an agency). Results indicated that a majority of interviewees believed sex work was stigmatized but attributed this stigma to society's tendency to conflate escort/erotic masseur with street-based prostitute and society's negative view of human sexuality in general and homosexuality in particular. It should be noted that interviewees did not necessarily perceive the gay community as more tolerant than the heterosexual community of persons involved in the male sex industry. In terms of how participants saw the sex trade, both prior to and during their involvement, multifarious viewpoints emerged (i.e., some engaged in "whore mythologizing" while others reported having no clearly defined perception of male sex workers). Finally, results suggested that some participants believed their involvement in a stigmatized industry was deleterious to them personally whereas others maintained that the consequences of being an escort/ erotic masseur were largely positive. PMID:18019075

  20. Male-Dominant Activation of Rat Renal Organic Anion Transporter 1 (Oat1) and 3 (Oat3) Expression by Transcription Factor BCL6

    PubMed Central

    Wegner, Waja; Burckhardt, Birgitta Christina; Burckhardt, Gerhard; Henjakovic, Maja

    2012-01-01

    Background Organic anion transporters 1 (Oat1) and 3 (Oat3) mediate the transport of organic anions, including frequently prescribed drugs, across cell membranes in kidney proximal tubule cells. In rats, these transporters are known to be male-dominant and testosterone-dependently expressed. The molecular mechanisms that are involved in the sex-dependent expression are unknown. Our aim was to identify genes that show a sex-dependent expression and could be involved in male-dominant regulation of Oat1 and Oat3. Methodology/Principal Findings Promoter activities of Oat1 and Oat3 were analyzed using luciferase assays. Expression profiling was done using a SurePrint G3 rat GE 8×60K microarray. RNA was isolated from renal cortical slices of four adult rats per sex. To filter the achieved microarray data for genes expressed in proximal tubule cells, transcription database alignment was carried out. We demonstrate that predicted androgen response elements in the promoters of Oat1 and Oat3 are not functional when the promoters were expressed in OK cells. Using microarray analyses we analyzed 17,406 different genes. Out of these genes, 56 exhibit a sex-dependent expression in rat proximal tubule cells. As genes potentially involved in the regulation of Oat1 and Oat3 expression, we identified, amongst others, the male-dominant hydroxysteroid (17-beta) dehydrogenase 1 (Hsd17b1), B-cell CLL/lymphoma 6 (BCL6), and polymerase (RNA) III (DNA directed) polypeptide G (Polr3g). Moreover, our results revealed that the transcription factor BCL6 activates promoter constructs of Oat1 and Oat3. Conclusion The results indicate that the male-dominant expression of both transporters, Oat1 and Oat3, is possibly not directly regulated by the classical androgen receptor mediated transcriptional pathway but appears to be regulated by the transcription factor BCL6. PMID:22530049

  1. Sentencing Male Sex Offenders Under the Age of 14: A Law Reform Advocacy Journey in Hong Kong.

    PubMed

    Ng, Wai-Ching Irene; Cheung, Monit; Ma, Anny Kit-Ying

    2015-01-01

    The common law presumption that a boy under the age of 14 is incapable of sexual intercourse has provoked controversial debates in Hong Kong. This article describes a 6-step advocacy journey to examine how community efforts have helped modify this law so that juvenile male sexual offenders under the age of 14 who have committed the crime of having sexual intercourse with underage females can be sentenced to receive appropriate treatment. Seven court cases provided by the magistrates' courts in Hong Kong were used in this advocacy effort for the removal of the presumption in July 2012. Although this effort has yet to reveal signs of effectiveness, it represents greater public awareness about providing rehabilitation appropriate for juvenile sex offenders through a formal sentence. Restorative justice, as opposed to retributive or punitive justice, places an emphasis on rehabilitation of the offender and restoration of victims to a place of wholeness. PMID:26061020

  2. Evidence for a Male Sex Pheromone in the Noctuid, Trichoplusia ni

    Microsoft Academic Search

    G. G. Grant

    1970-01-01

    THE hairpencils of several male Lepidoptera secrete volatile substances1-8. Aplin and Birch1 reported that the scent-brushes of some noctuids contain benzaldehyde as their chief component and they suggested that this substance might function as an aphrodisiac because the brushes were displayed during courtship, but they gave no evidence that the compound was olfactorily or otherwise stimulating to the insect. Recent

  3. Sex allocation in clonal plants: might clonal expansion enhance fitness gains through male function?

    Microsoft Academic Search

    Marcel E. Dorken; Wendy E. Van Drunen

    2010-01-01

    The returns on investment in sexual reproduction are described by fitness gain curves and the shapes of these curves affect,\\u000a among other things, the evolutionary stability of reproductive systems. The available evidence indicates that gain curves\\u000a for male function decelerate, corresponding to diminishing fitness returns on investment in pollen. In contrast, the gain\\u000a curve for female function is thought to

  4. Behavior of processionary males (Thaumetopoea pityocampa) induced by sex pheromone and analogs in a wind tunnel.

    PubMed

    Quero, C; Camps, F; Guerrero, A

    1995-12-01

    The behavioral response of processionary males (Thaumetopoea pityocampa) to the natural pheromone (Z)-13-hexadecen-11-ynyl acetate (1) and structurally related analogs in a wind tunnel is presented. Stereomerically pureZ-1 and a mixture with theE isomer in 80:20 ratio elicited similar attraction responses at 1 µg and higher. The activity was dose-dependent, being optimum at 1 µg with 90% and 80% of males contacting with the source in the presence of theZ-1 andZ/E-1, respectively. 11-Hexadecynyl acetate (2) functioned as a pheromone mimic, being able to induce the complete mate-finding behavioral sequence, although its activity was much lower than that of the pheromone. (Z)-13-Hexadecen-11-ynyl alcohol (3) and, particularly, (Z)-13-hexadecen-11-ynal (4) were potent inhibitors of the upwind flight response in mixtures withZ-1 in 99:1, 95:5, and 91:9 ratios. (Z)-1,1,1-Trifluoro-16-nonadecen-14-yn-2-one (5) also inhibited the response of males to pheromone, particularly in the source contact behavior. Comparison with activity displayed by analogs in field tests is also reported. PMID:24233899

  5. (Patho)physiology of cross-sex hormone administration to transsexual people: the potential impact of male-female genetic differences.

    PubMed

    Gooren, L J; Kreukels, B; Lapauw, B; Giltay, E J

    2015-02-01

    There is a limited body of knowledge of desired and undesired effects of cross-sex hormones in transsexual people. Little attention has been given to the fact that chromosomal configurations, 46,XY in male-to-female transsexuals subjects (MtoF) and 46,XX in female-to-male transsexual subjects (FtoM), obviously, remain unchanged. These differences in their genomes cause sex differences in the functions of cells. This study reviews sex differences in metabolism/cardiovascular pathology, immune mechanisms, bone (patho)physiology and brain functions and examines whether they are, maybe partially, determined by genetic mechanisms rather than by (cross-sex) hormones. There do not appear to be major genetic impacts on the changes in bone physiology. Also immune functions are rather unaffected and the evidence for an increase of autoimmune disease in MtoF is preliminary. Brain functions of transsexuals may have differed from controls before cross-sex hormones; they do undergo shifts upon cross-sex hormone treatment, but there is no evidence for changes in sex-specific brain disease. The prevalence of cardiovascular disease is higher in MtoF receiving oestrogens than in FtoM receiving androgens. While type of oestrogen and route of administration might be significant, it is reasonable to speculate that nonhormonal/genetic factors play a role. PMID:25495275

  6. HIV prevention among male clients of female sex workers in Kaolack, Senegal: results of a peer education program.

    PubMed

    Leonard, L; Ndiaye, I; Kapadia, A; Eisen, G; Diop, O; Mboup, S; Kanki, P

    2000-02-01

    This article reports the results of a peer-led HIV prevention education and condom promotion program among transport workers in Kaolack, Senegal. As part of a 2-year longitudinal follow-up study, changes in men's AIDS-related knowledge, sexual behavior, condom use, and perceived barriers to condom use were evaluated by self-reports obtained from a systematic sample of transport workers interviewed before and after intervention. In addition to men's self-reports, preintervention and postintervention data on men's sexual and condom use behavior were gathered from a sample of licensed, commercial sex workers, who cited transport workers as their primary source of clients. Significant increases in men's HIV-related knowledge, previous use of condoms (from 30.4% to 53.5%), and consistent condom use with regular sex partners were documented over the study period, as were significant declines in perceived barriers to condom use. Though men reported significantly fewer sexual encounters with casual and commercial partners at follow-up compared to baseline, these data were unreliable. Women's postintervention reports indicate that a greater proportion of clients (including, but not limited to transport workers) "always" agree to use condoms (p < .01) compared with baseline and that fewer men offer more money for unprotected sex (p < .01). However, women also report taking greater initiative in the mechanics of condom use (supplying the condom, putting it on, and taking it off) than they did prior to the intervention, and significantly (p < .05) fewer women think that most of their clients know how to use a condom. The findings indicate that the peer-mediated intervention had a positive impact on several important outcomes measured and suggest that HIV prevention efforts need to focus on male client groups despite the logistical and methodological challenges. PMID:10749384

  7. Condom Use Among Men Who Have Sex With Men and Male-to-Female Transgenders in Jakarta, Indonesia.

    PubMed

    Safika, Iko; Johnson, Timothy P; Cho, Young Ik; Praptoraharjo, Ignatius

    2013-11-01

    This article examined differences in condom use during anal intercourse among men who have sex with men (MSM) and male-to-female transgender women in Jakarta, Indonesia. A cross-sectional design, structured interviews, and hierarchical linear modeling were used to examine condom use among MSM recruited from entertainment places (EPs; e.g., discotheques/dance clubs/karaoke bars), massage parlors (MPs), and among transgender women who congregated and/or sought sexual partners on streets/parks (S/P). The sample consisted of 91, 97, and 114 of MSM-EP, MSM-MP, and transgender-S/P, respectively. Respondents reported on 641 unique sexual partner encounters, which were "nested" within 302 respondents. Reported condom use was high, 66%, 84%, and 83% for MSM-EP, MSM-MP, and transgender-S/P, respectively, and varied across type of respondent. At the individual level, depressive symptoms and history of physical abuse during childhood and adulthood were associated with lower condom use (p < .05). By contrast, having a higher level of education was associated with more condom use (p < .05). At the partner level, condom use was associated with type of partners and the use of club drugs before sex. HIV-prevention efforts should take into account the multilevel determinants of condom use within these populations. PMID:24203992

  8. Medfly (Diptera:Tephritidae) Genetic Sexing: Large-Scale Field Comparison of Males-Only and Bisexual Sterile Fly Releases in Guatemala

    Microsoft Academic Search

    P. Rendón; D. McInnis; D. Lance; J. Stewart

    2004-01-01

    The effect of releases of bisexual (males and female) and unisexual (male only) sterilized medßies was compared in three large Þeld evaluations over a 3-yr period (1995Ð1997) in southwestern Guatemala. The two strains tested were a genetic sexing strain, Vienna-4\\/Tol-94, carrying the temperature sensitive tsl gene to eliminate females in the egg stage, and the standard bisexual Petapa strain. Flies

  9. Male-Dependent Doubly Uniparental Inheritance of Mitochondrial DNA and Female-Dependent Sex-Ratio in the Mussel Mytilus Galloprovincialis

    PubMed Central

    Saavedra, C.; Reyero, M. I.; Zouros, E.

    1997-01-01

    We have investigated sex ratio and mitochondrial DNA inheritance in pair-matings involving five female and five male individuals of the Mediterranean mussel Mytilus galloprovincialis. The percentage of male progeny varied widely among families and was found to be a characteristic of the female parent and independent of the male to which it was mated. Thus sex-ratio in Mytilus appears to be independent of the nuclear genotype of the sperm. With a few exceptions, doubly uniparental inheritance (DUI) of mtDNA was observed in all families fathered by four of the five males: female and male progeny contained the mother's mtDNA (the F genome), but males contained also the father's paternal mtDNA (the M genome). Two hermaphrodite individuals found among the progeny of these crosses contained the F mitochondrial genome in the female gonad and both the F and M genomes in the male gonad. All four families fathered by the fifth male showed the standard maternal inheritance (SMI) of animal mtDNA: both female and male progeny contained only the maternal mtDNA. These observations illustrate the intimate linkage between sex and mtDNA inheritance in species with DUI and suggest different major roles for each gender. We propose a model according to which development of a male gonad requires the presence in the early germ cells of an agent associated with sperm-derived mitochondria, these mitochondria are endowed with a paternally encoded replicative advantage through which they overcome their original minority in the fertilized egg and this advantage (and, therefore, the chance of an early entrance into the germ line) is countered by a maternally encoded egg factor. PMID:9093859

  10. Risk Factors for HIV/Syphilis Infection and Male Circumcision Practices and Preferences among Men Who Have Sex with Men in China

    PubMed Central

    Zhang, Linglin; Li, Tian; Lai, Wenhong; Jia, Yujiang; Aliyu, Muktar H.; Do, Mai; Huang, Wanli; Du, Shuping; Xu, Jie; Zhou, Jiushun; Liang, Shu; Yu, Fei; Zhang, Yanqing

    2014-01-01

    Objective. To investigate factors associated with HIV infection and the frequency and willingness of male circumcision among men who have sex with men (MSM) in Chengdu city, China. Methods. A cross-sectional survey provided information on participants' demographics, risk behaviors, circumcision, and uptake of HIV prevention services. Results. Of 570 participants, 13.3% were infected with HIV and 15.9% with syphilis. An estimated 43.0% of respondents reported having unprotected receptive anal intercourse, and 58.9% reported having ?2 male sexual partners in the past 6 months. Multivariable logistic regression revealed that syphilis, more male sex partners, predominantly receptive anal intercourse, and exclusively receptive male sex were associated with HIV infection. Higher level of education and peer education service were inversely associated with HIV infection. Nearly a fifth (18.0%) of participants were circumcised. More than half of uncircumcised participants expressed willingness to be circumcised. Conclusion. This study reveals a high prevalence of HIV and syphilis among MSM in Chengdu province of China. The frequency of unprotected receptive anal intercourse and multiple male sexual partnerships highlight the urgency for an effective comprehensive HIV prevention strategy. Although the willingness to accept male circumcision (MC) is high, further research is needed to assess the protective effective of MC among MSM. PMID:24795883

  11. Organizing Participation in Cross-Sex Jump Rope: Situating Gender Differences within Longitudinal Studies of Activities.

    ERIC Educational Resources Information Center

    Goodwin, Marjorie Harness

    2001-01-01

    Investigates how children use directives and forms of exclusion to organize play activity. Elementary school children of mixed ethnicity were observed playing jump rope over one month. Girls' dominance in the game was observed to change over time. The ability to use actions that tell others what to do in a very direct fashion in cross-sex

  12. Regret after sex reassignment surgery in a male-to-female transsexual: a long-term follow-up.

    PubMed

    Olsson, Stig-Eric; Möller, Anders

    2006-08-01

    This case report describes a four-decade presentation of a non-homosexual gender dysphoric male patient. The case material was collected from two main sources. One of the authors had weekly therapy sessions with the patient over a period of 2 years almost 15 years after sex reassignment surgery. Information was also gained from the patient's medical records covering the period from the early 1960s to the early 1990s. Over the years, the patient fulfilled the criteria for different diagnoses: overanxious reaction of childhood, fetishism and transvestism during adolescence, and transsexualism during adolescence and early adulthood. The purpose of this report was to shed light on aspects of regret, its manifestation in a male-to-female transsexual with psychiatric co-morbidity, and to show the complexity of the process of adjustment when regret is involved. The present case is an argument for a strict interpretation of the Standards of Care provided by the Harry Benjamin International Gender Dysphoria Association in terms of evaluating patients' mental health, apart from the evaluation of the gender identity disorder, and the patients' subsequent need for treatment interventions. PMID:16900416

  13. Comparison of Expressed Sequence Tags from Male and Female Sexual Organs of Marchantia polymorpha

    Microsoft Academic Search

    R. Nishiyama; Kenji MIURA; Megumi SAKAIDA; Sachiko OKADA; Kaoru KONO; Masayoshi TAKAHAMA; Takefumi SONE; Mizuki TAKENAKA; Hideya FUKUZAWA; Kanji OHYAMA

    2000-01-01

    A total of 935 expressed sequence tags (ESTs) from male immature sexual organ were determined, of which 600 ESTs were assembled into 110 non-redundant groups, resulting in 445 unique EST sequences. Of these, 244 sequences shared significant similarities to known nucleotide or amino acid sequences in other organisms. The remaining 201 unique sequences showed no significant matches and thus are

  14. Gender constructions of male sex offenders in Germany: narrative analysis from group psychotherapy.

    PubMed

    Moertl, Kathrin; Buchholz, Michael B; Lamott, Franziska

    2010-02-01

    This study was conducted to analyze how male sexual offenders construct mental images of masculinity and femininity to provide insight into therapeutic treatment for such patients. Thematerial examined in this studywas comprised of 21 videotaped prison group therapy sessions in which the participating sexual offenders talked about their crimes and biographies. Aqualitative data analysis softwarewas usedto apply a modified grounded theorymethodology to the transcribed sessions. The resulting categories can be understood as descriptions of how the imprisoned men constructed gender images, and were based on three narrative levels: the structure of narration, the narrative positions in the story, and the interaction between the narrator and the other participants. According to the categories describedin the narrative positions (the narrated self and the narrated significant male others), we constructed masculinity categorizations which corresponded to specific images of femininity (derived from the narrated significant female others).The constructionsprovided insight into the selfimage of the narrator, as well as the accountability and positioning of himself and the other in regard to perpetrator-victim constructions. The study further revealed whether the participants either accepted or rejected responsibility and guilt for their crimes; this is essential for psychotherapeutic process and treatment. PMID:20054631

  15. Sex, dependency, and helping

    Microsoft Academic Search

    Charles L. Gruder; Thomas D. Cook

    1971-01-01

    Examined whether the difference in the helping behavior of males and females is due to the sex of the person giving help or the sex of the person receiving it. In an experiment with 52 male and 52 female undergraduates, dependency, sex of potential helper, and sex of dependent person were all varied factorially. An interaction of dependency and sex

  16. Carotenoid-based ornaments of female and male American goldfinches (Spinus tristis) show sex-specific correlations with immune function and metabolic rate.

    PubMed

    Kelly, Ryan J; Murphy, Troy G; Tarvin, Keith A; Burness, Gary

    2012-01-01

    Conspicuous ornamentation has been linked to immunological and physiological condition in males of many species. In species where both sexes are ornamented, it is unclear whether the signal content of ornaments differs between males and females. We examined the immunological and physiological correlates of carotenoid-based bill and plumage ornamentation in American goldfinches Spinus tristis, a species in which bright orange bills are sexually monomorphic but yellow plumage is sexually dimorphic during the breeding season. Because bill color is dynamic over short periods while plumage color is static over longer time frames, we tested whether these signals have the potential to provide temporal information about immunity and condition. In both sexes, bill color (but not plumage color) was negatively related to leukocyte differential, a measure of recent stress, while plumage color (but not bill color) was positively related to resting metabolic rate. In females, bill color also positively correlated with immunoglobulin Y, a component of acquired immunity, while plumage color positively predicted natural antibody levels, a component of innate immunity. In males, neither bill color nor plumage color predicted immune function, suggesting that the mechanisms underlying these signals vary with sex. Our results demonstrate that dynamic signals such as bill coloration do not merely reflect the same information provided by static signals but that these two classes of signal provide information about different temporal aspects of phenotypic quality. Furthermore, our results indicate that a signal expressed in both sexes has the potential to provide different information depending on the sex of the bearer. PMID:22705485

  17. The Male-Female Health-Survival Paradox and Sex Differences in Cohort Life Expectancy in Utah, Denmark and Sweden 1850-1910

    PubMed Central

    Lindahl-Jacobsen, Rune; Hanson, Heidi A.; Oksuzyan, Anna; Mineau, Geraldine P.; Christensen, Kaare; Smith, Ken R.

    2013-01-01

    Purpose In Utah, prevalence of unhealthy male risk behaviours are lower than in most other male populations while women experience higher mortality risk due to higher fertility rates. Therefore, we hypothesize that the Utah sex differential in mortality would be small and less than in Sweden and Denmark. Methods Life tables from Utah, Denmark and Sweden, were used to calculate cohort life expectancies for men and women born 1850-1910. Results The sex difference in cohort life expectancy was similar or larger in Utah when compared to Denmark and Sweden. The change over time in the sex differences in cohort life expectancy was approximately two years smaller for active Mormons in Utah than for other groups suggesting lifestyle as an important component for the overall change seen in cohort life expectancy. Sex differences in cohort life expectancy at age 50 were similar for individuals actively affiliated with the Church of Jesus Christ of Latter-day Saints and for Denmark and Sweden. Conclusions The hypothesis that a smaller sex difference in cohort life expectancies in Utah would be detected in relation to Denmark and Sweden was not supported. In Utah the male-female differences in life expectancy remain substantial pointing towards biological mechanisms, or other unmeasured risk factors. PMID:23453386

  18. An interspecific comparison using immunofluorescence reveals that synapse density in the avian song system is related to sex but not to male song repertoire size

    Microsoft Academic Search

    Paul M. Nealen

    2005-01-01

    Immunofluorescent labeling of synaptic vesicle protein 2 (SV2) and confocal microscopy were employed to assess the role of synapse density in the functioning of the avian song system. Synapse density in premotor nuclei HVC and RA was measured, in both sexes of two species characterized by male-only singing behavior: the zebra finch Taeniopygia guttata, which sings a single, stereotyped song,

  19. Effect of design of a sex-pheromone-baited delta trap on behavior and catch of maleEpiphyas postvittana (Walker).

    PubMed

    Foster, S P; Muggleston, S J

    1993-11-01

    Through field trials and wind-tunnel studies, we have demonstrated that certain structural features of a sex-pheromone-baited delta trap affect catch of light-brown apple moth,Epiphyas postvittana, males, by influencing behaviors used to enter and exit the trap. Field catch of males was dependent upon length (and width) of the trap, with increases in length yielding linear increases in catch. In the wind tunnel, similar numbers of males entered the two traps, but significantly fewer males exited the longer trap within 1 min after entering it. Although males landed on the sticky surface at similar distances from the downwind entrances of the traps, they were stuck farther upwind on the longer trap. Thus, it is probable that the increase in field catch with increase in trap length relates to the increase in distance (and hence time) that males walk on the sticky surface, towards the pheromone source, before attempting to exit. The bottom barriers (as well as additional barriers at the top and sides) at the entrances of the trap also significantly influenced trap catch. The barriers apparently influence trap catch in two ways. Firstly, they hinder the exit of males from the trap, thus diverting males back into the trap and increasing their chance of being caught. Secondly, they influence where the male lands on the sticky surface; with higher barriers, males land farther upwind (i.e., nearer the source), and thus farther from an exit. Finally, as the source was suspended higher above a horizontal surface, greater numbers of males landed on the source. This result shows that the position where a maleE. postvittana lands is influenced by the relationship of the source to the surface and suggests that trap catch of males may similarly be influenced (i.e., by inducing males to land farther from the exits). PMID:24248716

  20. Climate influences fledgling sex ratio and sex-specific dispersal in a seabird.

    PubMed

    Barros, Alvaro; Alvarez, David; Velando, Alberto

    2013-01-01

    Climate influences the dynamics of natural populations by direct effects over habitat quality but also modulating the phenotypic responses of organisms' life-history traits. These responses may be different in males and females, particularly in dimorphic species, due to sex-specific requirements or constraints. Here, in a coastal seabird, the European shag (Phalacrocorax aristotelis), we studied the influence of climate (North Atlantic Oscillation, NAO; Sea Surface Temperature, SST) on two sex-related population parameters: fledgling sex ratio and sex-specific dispersal. We found that fledgling sex ratio was female skewed in NAO-positive years and male skewed in NAO-negative years. Accordingly, females dispersed a longer distance in NAO-positive years when females were overproduced, and on the contrary, males dispersed more in NAO-negative years. Overall, our findings provide rare evidence on vertebrates with genetic sex determination that climate conditions may govern population dynamics by affecting sex-specific density and dispersal. PMID:23951144

  1. Low-intensity, short-duration thermal stimulation during the late phase of incubation alters secondary sex ratio in favour of males.

    PubMed

    Elmehdawi, A; Hall, M; Skewes, P; Wicker, D; Maurice, D V; Smith, J; Benton, R

    2015-06-01

    1. In two experiments, two setters and hatchers, with a capacity of 42 240 eggs each, were used to investigate the effect of low-intensity, short-duration thermal stimuli during the late phase of incubation on hatchability, sex ratio and grow-out performance of broilers under field conditions. 2. Eggs in the test group had the same physical environment as eggs in the control group except that incubation temperature was increased by 0.5°C for 2 h/d above the control group from 18 to 20 d of incubation. 3. Thermal stimulation significantly increased the proportion of males hatched in both experiments. In experiment 2, evaluation at 7 d of age showed that the proportion of males in the test group was still significantly higher than in the control group. 4. In experiment 2, hatch residue was examined and the proportion of unhatched male embryos was significantly greater in the control group than in the test group. 5. Thermal stimulation did not have a significant influence on post-hatch performance of broiler chickens to market age. 6. The results demonstrated that thermal stimulation of 0.5°C for 2 h/d above the control during late incubation shifted the sex ratio at hatch and at 7 d in favour of males. The difference in secondary sex ratio was due to increased survival of male embryos in the test group. PMID:25929286

  2. An interspecific comparison using immunofluorescence reveals that synapse density in the avian song system is related to sex but not to male song repertoire size.

    PubMed

    Nealen, Paul M

    2005-01-25

    Immunofluorescent labeling of synaptic vesicle protein 2 (SV2) and confocal microscopy were employed to assess the role of synapse density in the functioning of the avian song system. Synapse density in premotor nuclei HVC and RA was measured, in both sexes of two species characterized by male-only singing behavior: the zebra finch Taeniopygia guttata, which sings a single, stereotyped song, and the Carolina wren Thryothorus ludovicianus, which sings a large repertoire of different songs. Multiple levels of analyses demonstrate overall similarity of synapse density between nuclei HVC and RA, suggesting that synapse density is regulated uniformly across these regions within individuals. Male zebra finches and male Carolina wrens have equivalent synapse densities, suggesting a common pattern of masculinized development despite dramatic behavioral differences. Female Carolina wrens have synaptic density similar to that of males of both species, while female zebra finches exhibit greater synaptic densities in both regions than do male zebra finches or both sexes of wrens. Prior reports implicate testosterone as a regulator of synapse density in this system; sex differences in circulating or neural testosterone may contribute to the sexual dimorphism of synapse density observed here. Interspecific comparison of song system synapse density in nonsinging females suggests that synapse density in female songbirds may be a particularly labile trait. PMID:15680941

  3. A homolog of male sex-determining factor SRY cooperates with a transposon-derived CENP-B protein to control sex-specific directed recombination

    PubMed Central

    Matsuda, Emiko; Sugioka-Sugiyama, Rie; Mizuguchi, Takeshi; Mehta, Sameet; Cui, Bowen; Grewal, Shiv I. S.

    2011-01-01

    Schizosaccharomyces pombe cells switch mating type by replacing genetic information at the expressed mat1 locus with sequences copied from mat2-P or mat3-M silent donor loci. The choice of donor locus is dictated by cell type, such that mat2 is the preferred donor in M cells and mat3 is the preferred donor in P cells. Donor choice involves a recombination-promoting complex (RPC) containing Swi2 and Swi5. In P cells, the RPC localizes to a specific DNA element located adjacent to mat3, but in M cells it spreads across the silent mating-type region, including mat2-P. This differential distribution of the RPC regulates nonrandom choice of donors. However, cell-type–specific differences in RPC localization are not understood. Here we show that the mat1-M–encoded factor Mc, which shares structural and functional similarities with the male sex-determining factor SRY, is highly enriched at the swi2 and swi5 loci and promotes elevated levels of RPC components. Loss of Mc reduces Swi2 and Swi5 to levels comparable to those in P cells and disrupts RPC spreading across the mat2/3 region. Mc also localizes to loci expressed preferentially in M cells and to retrotransposon LTRs. We demonstrate that Mc localization at LTRs and at swi2 requires Abp1, a homolog of transposon-derived CENP-B protein and that loss of Abp1 impairs Swi2 protein expression and the donor choice mechanism. These results suggest that Mc modulates levels of recombination factors, which is important for mating-type donor selection and for the biased gene conversion observed during meiosis, where M cells serve as preferential donors of genetic information. PMID:22042869

  4. Changes in profiles of serum sex steroids of male buffaloes from birth to maturity.

    PubMed

    Sharma, I J; Agarwal, S P; Agarwal, V K; Dwaraknath, P K

    1984-08-01

    Age-related changes in testosterone, progesterone and estradiol 17-beta were determined by radioimmunoassay (RIA) in the serum of 155 male buffalo calves of varying ages. The calves were classified into 17 age groups. The mean weight of calves increased from 33.6+/-9.6 kg at one week of age to 531+/-41.4 kg at 42 months. The testosterone levels were less than 100 pg/ml from birth until 15 months of age, followed by peak concentrations of 422+/-79 pg/ml at 24 to 30 months and 793+/-193 pg/ml at 42 to 48 months (corresponding to puberty and maturity, respectively). The progesterone levels were higher in newly born calves and mature bulls. Otherwise, the levels continued to be low throughout the period of growth and development. Estradiol 17-beta was significantly higher in postnatal calves up to two months of age. The testosterone revealed a positive correlation with weight and age while E2 17-beta showed a negative correlation with age. These results do not support a direct role of peripheral progesterone and estradiol 17-beta in the onset of puberty and sexual maturity of buffalo bulls. PMID:16725948

  5. Do Male and Female Cowbirds See Their World Differently? Implications for Sex Differences in the Sensory System of an Avian Brood Parasite

    PubMed Central

    Fernández-Juricic, Esteban; Ojeda, Agustin; Deisher, Marcella; Burry, Brianna; Baumhardt, Patrice; Stark, Amy; Elmore, Amanda G.; Ensminger, Amanda L.

    2013-01-01

    Background Male and female avian brood parasites are subject to different selection pressures: males compete for mates but do not provide parental care or territories and only females locate hosts to lay eggs. This sex difference may affect brain architecture in some avian brood parasites, but relatively little is known about their sensory systems and behaviors used to obtain sensory information. Our goal was to study the visual resolution and visual information gathering behavior (i.e., scanning) of brown-headed cowbirds. Methodology/Principal Findings We measured the density of single cone photoreceptors, associated with chromatic vision, and double cone photoreceptors, associated with motion detection and achromatic vision. We also measured head movement rates, as indicators of visual information gathering behavior, when exposed to an object. We found that females had significantly lower density of single and double cones than males around the fovea and in the periphery of the retina. Additionally, females had significantly higher head-movement rates than males. Conclusions Overall, we suggest that female cowbirds have lower chromatic and achromatic visual resolution than males (without sex differences in visual contrast perception). Females might compensate for the lower visual resolution by gazing alternatively with both foveae in quicker succession than males, increasing their head movement rates. However, other physiological factors may have influenced the behavioral differences observed. Our results bring up relevant questions about the sensory basis of sex differences in behavior. One possibility is that female and male cowbirds differentially allocate costly sensory resources, as a recent study found that females actually have greater auditory resolution than males. PMID:23544049

  6. The ovary retains male potential after the thermosensitive period for sex determination in the turtle Emys orbicularis.

    PubMed

    Dorizzi, M; Richard-Mercier, N; Pieau, C

    1996-07-01

    Emys orbicularis is a turtle with temperature-dependent sex determination. The thermosensitive period (TSP) lies between embryonic stages 16 and 22. Gonadal differentiation begins during this period involving oestrogens. Treatment with oestrogens during TSP results in the differentiation of ovaries at a male-producing temperature (25 degrees C), whereas treatment with an antioestrogen (tamoxifen) or with nonsteroidal aromatase inhibitors results in gonadal masculinization at a female-producing temperature (30 degrees C). The present study examines the effects on the ovary of inhibiting aromatase activity after TSP. Eggs of E. orbicularis incubated at 30 degrees C were given five or seven applications of 10 micrograms aromatase inhibitor Letrozole (CGS 20267) in ethanol, between stages 22+ and 24-25 when ovarian aromatase activity strongly increases. Individuals which received five applications were sacrificed at stages 24(+)-25. Those which received seven applications were sacrificed either at stage 25+ (close to hatching), or 34-36 days after hatching. Gonadal aromatase activity and related gonadal structure were studied in each individual. In the three series, the gonadal aromatase activity in individuals treated with Letrozole varied from similar or close to that in controls to much lower, and the gonadal structure varied from ovary-like to ovotestis. Ovotestes had the lowest levels of aromatase activity, under 4 fmoles/h/gonad, close to testis levels. They were found in 7 out of 26 individuals given Letrozole. Besides ovotestes, gonads presenting various degrees of masculinization, with enlarged epithelial cords and lacunae in the medulla, were found. Therefore, by inhibiting aromatase activity and thus estrogen synthesis, we were able to obtain the differentiation of testis-like cords or tubes in ovaries of E. orbicularis, after the period of temperature sensitivity. These results show that the ovary retains male potential after this period. Thus, besides their implication during the critical embryonic period for gonadal sex differentiation, oestrogens play a role in maintaining the ovarian structure after this period. A decrease in oestrogen levels could explain some other cases of ovarian masculinization known in vertebrates. PMID:8765049

  7. Winter profile of plasma sex steroid levels in free-living male western diamond-backed rattlesnakes, Crotalus atrox (Serpentes: Viperidae).

    PubMed

    Schuett, Gordon W; Repp, Roger A; Taylor, Emily N; DeNardo, Dale F; Earley, Ryan L; Van Kirk, Edward A; Murdoch, William J

    2006-10-01

    Recent field studies on the reproductive ecology of western diamond-backed rattlesnakes (Crotalus atrox) from populations in southern Arizona showed significant differences in the concentration of plasma sex steroids (testosterone, T; 5alpha-dihydrotestosterone, DHT; and 17beta-estradiol, E2) throughout the active season (March-October), and peak levels were coincident with the two mating periods (late summer and early spring). There is, however, no information on levels of sex steroids during winter. Similar to most snakes, hibernating individuals of C. atrox are typically inaccessible, but in southern Arizona, where environmental conditions are typically mild during winter, adult males frequently bask at or near the entrances of communal dens. Basking activity, therefore, offers a unique logistical opportunity to assess the complete annual profile of plasma sex steroid levels in males of a temperate reptile in nature. From November to February, we measured levels of plasma T, DHT, and E2 in adult male C. atrox that were located basking at communal dens. Additionally, cloacal, core body, and ambient air temperatures were obtained to investigate potential relationships between body temperatures and levels of sex steroids. Mean levels of T, DHT, and E2 were relatively high, and the concentration hierarchy was T>DHT>E2. Mean levels of T, DHT, and E2 showed no significant variation across the four months of sampling; however, E2 levels decreased progressively. In the annul cycle, sex steroid levels during winter were not basal when compared to values obtained during the active season. Mean cloacal temperatures of basking males were significantly higher than core body temperatures of non-basking males (inside dens) from November-December, and in February, which suggests that one function of winter basking is to elevate body temperatures. Steroid levels, nonetheless, were not significantly correlated with cloacal temperatures. We suggest that future field studies of male C. atrox should: (a) investigate sex steroid levels in non-basking individuals and (b) test whether elevated levels of sex steroids during winter facilitate the large increases that occur in early spring, which are coincident with the second mating season. Our findings on the reproductive biology of C. atrox and other viperids are discussed in the context of the associated-dissociated model of reproduction. PMID:16828091

  8. The Earliest Case of Extreme Sexual Display with Exaggerated Male Organs by Two Middle Jurassic Mecopterans

    PubMed Central

    Wang, Qi; Shih, Chungkun; Ren, Dong

    2013-01-01

    Background Many extant male animals exhibit exaggerated body parts for display, defense or offence in sexual selection, such as male birds of paradise showing off colorful and elegant feathers and male moose and reindeers bearing large structured antlers. For insects, male rhinoceros and stag beetles have huge horn-like structure for fighting and competition and some male Leptopanorpa scorpionflies have very long abdominal terminal segments for sexual display and competition. Fossil records of insects having exaggerated body parts for sexual display are fairly rare. One example is two male holcorpids with elongate abdominal segments from sixth (A6) to eighth (A8) and enlarged male genitalia from Eocene, suggesting evolution of these characters occurred fairly late. Principal Findings We document two mecopterans with exaggerated male body parts from the late Middle Jurassic Jiulongshan Formation in northeastern China. Both have extremely extended abdominal segments from A6 to A8 and enlarged genitalia, which might have been used for sexual display and, to less extent, for fighting with other males in the competition for mates. Although Fortiholcorpa paradoxa gen. et sp. nov. and Miriholcorpa forcipata gen. et sp. nov. seem to have affinities with Holcorpidae, we deem both as Family Incertae sedis mainly due to significant differences in branching pattern of Media (M) veins and relative length of A8 for F. paradoxa, and indiscernible preservation of 5-branched M veins in hind wing for M. forcipata. Conclusions/Significance These two new taxa have extended the records of exaggerated male body parts of mecopterans for sexual display and/or selection from the Early Eocene to the late Middle Jurassic. The similar character present in some Leptopanorpa of Panorpidae suggests that the sexual display and/or sexual selection due to extremely elongated male abdominal and sexual organs outweigh the negative impact of bulky body and poor mobility in the evolutionary process. PMID:23977031

  9. Sex Differences in Lopinavir (LPV) and Ritonavir (RTV) Pharmacokinetics (PKs) Among HIV-infected Females and Males

    PubMed Central

    Umeh, OC; Currier, JS; Park, JG; Cramer, Y; Hermes, AE; Fletcher, CV

    2012-01-01

    Objectives We compared the pharmacokinetics of lopinavir (LPV) and ritonavir (RTV) between female and males. Methods This two-step, multicenter, pharmacokinetic study enrolled HIV-infected adults on lopinavir/ritonavir (LPV/r) capsules (400/100mg BID) plus 1 or more NRTIs. All subjects underwent 12 hour pharmacokinetic sampling. The PK sampling was repeated in subjects receiving the LPV/r tablet formulation. Results Step 1 enrolled 37 women and 40 men; step 2 included 42 subjects from step 1 plus 35 new participants (39 women and 38 men). LPV pharmacokinetics in females and males were not significantly different with either formulation. Females had significantly higher median RTV AUC0–12h with both the soft gel capsule and tablet formulations (SGC:5395 vs. 4119 ng*hr/ml, p=0.026; tablet 5310 vs. 3941 ng*hr/ml, p=0.012), higher median Cmax (SGC:802 vs. 635 ng/mL, p=0.032; tablet: 773 vs. 570 ng/ml, p=0.006)) and lower median CL/F (SGC:18.54 vs. 24.31 L/hour, p=0.026; tablet: 18.83 vs. 25.37 L/hour, p=0.012). RTV CL/F was slower in females after weight adjustment with both formulations. Conclusion The pharmacokinetics of LPV in the SGC and tablet formulations are comparable in HIV infected subjects. Females had higher RTV AUC0–12h and lower CL/F with both formulations. The mechanism of the sex difference in RTV CL/F warrants elucidation. PMID:21233301

  10. Sex Workers, Fem Queens, and Cross-Dressers: Differential Marginalizations and HIV Vulnerabilities Among Three Ethnocultural Male-to-Female Transgender Communities in New York City

    PubMed Central

    Hwahng, Sel Julian; Nuttbrock, Larry

    2008-01-01

    This article describes 3 distinct ethnocultural male-to-female transgender communities in New York City: the low-income African American/Black1 and Latina(o) House Ball community; low-income, often undocumented immigrant Asian sex workers; and middle-class White cross-dressers. These communities are highly socially isolated from each other and are more connected to their ethnocultural contexts than to an abstract and shared transgender identity. Whereas previous research either has viewed male-to-female transgender people as one monolithic group or has separated them into abstract racial categories unconnected to their communities and lifestyles, this article positions them within specific social networks, cultures, neighborhoods, and lifestyles. With regard to HIV vulnerabilities, violence, and rape, House Ball community members seemed to engage in the riskiest form of survival sex work, whereas Asian sex workers seemed to engage in moderate-risk survival sex work. White cross-dressers seemed to engage in very low-risk recreational sex work.2 PMID:19079558

  11. Personal or relational? Examining sexual health in the context of HIV serodiscordant same-sex male couples

    PubMed Central

    Gamarel, K.E.; Starks, T.J; Dilworth, S.E.; Neilands, T.B.; Taylor, J.M.; Johnson, M.O.

    2014-01-01

    Couples’ ability to adopt a “we” orientation has been associated with optimal health outcomes. This study examined how personal and relational motivations are uniquely associated with unprotected anal intercourse (UAI), protected anal intercourse (PAI), and the absence of sexual activity within HIV-serodiscordant same-sex male couples. HIV-positive men and their HIV-negative partners (n = 116 couples, 232 men) completed questionnaires and HIV-positive men had blood drawn for viral load. Results of a multinomial logistic regression illustrated that sexual satisfaction was positively associated with PAI among HIV-negative partners and negatively associated with PAI among HIV-positive partners. Endorsing a “we” orientation was positively associated with PAI among HIV-positive partners. Findings suggest that HIV-positive partners who espouse a “we” orientation may be willing to forgo their personal interests to protect their HIV-negative partners from HIV transmission. Couples-based interventions are warranted to help strengthen relationship dynamics to enhance the sexual health of serodiscordant couples. PMID:23636681

  12. Epidemiology of male same-sex behaviour and associated sexual health indicators in low- and middle-income countries: 2003–2007 estimates

    PubMed Central

    Cáceres, C F; Konda, K; Segura, E R; Lyerla, R

    2008-01-01

    Objectives: To conduct a systematic review of published and unpublished data from research and public health information systems on the prevalence of male-to-male sex in the total male population; as well as among men who have sex with men (MSM), data on prevalence of heterosexual activity and heterosexual unions; prevalence of condom use with male and female partners; and prevalence of HIV infection and other sexually transmitted infections (STIs). Methods: Key indicators were defined (a) among men in the general population: prevalence of sex with a man ever and last year; (b) among MSM: prevalence of heterosexual experiences ever and last year; proportion of male-female transgenders; proportion of sex workers; prevalence of HIV and other STIs, condom use in last sexual encounter; consistent condom use with men last year; never used a condom with a man. With help from key informants, study searches were conducted in Pubmed, LILLACS, institutional databases, conference records and other sources. Methodology and quality of information were assessed, and the best data available for 2003–7 were selected. Indicator estimates from each study were used to propose regional estimate ranges. Results: A total of 83 new entries were entered into the database in addition to the previous 561, totalling 644. Of these, 107 showing 2003–7 data were selected. Many new studies came from sub-Saharan Africa, portraying hidden HIV epidemics among MSM. The most frequently reported estimate was HIV infection, with high estimate ranges in most of the regions, except for Middle East and North Africa and Eastern Europe. The next most frequently reported was lifetime frequency of heterosexual sex, showing that roughly 50% of MSM ever had sex with a woman. The small number of newer studies reporting prevalence of “sex with a man in last 12 months” between 2003 and 2007, did not warrant enough new evidence to revise our 2005 size estimates for MSM populations. Conclusions: A considerable number of new studies with estimates of relevance to understanding sexual behaviour and HIV among MSM were identified, with an encouraging amount of new data coming from sub-Saharan Africa. However, limitations in the quality, utility and comparability of available information persist. At least three measures could be promoted for use in surveillance and academic studies: standardised indicators for MSM studies; standardised operational definitions of, and instructions to describe, variables; and standardised research designs and data gathering strategies. A prerequisite for this all is intense advocacy to ensure a social climate in which research into such matters is prioritised, resources are made available as needed and the human rights of MSM are respected. PMID:18647866

  13. Human vocal organ: visible-human-male-based three-dimensional visualization

    NASA Astrophysics Data System (ADS)

    Kim, Jae-woo; Lee, Donghun; Han, Jong H.; Kim, Bohyung; Kim, Dongsung; Kang, Heung Sik

    2002-05-01

    The Visible Human Project planned and promoted by National Library of Medicine (NLM) provides cryosection images of the normal male and female human bodies. The anatomy of human vocal organ is difficult to understand and to imagine due to its complexity. The purpose of this study is to develop the three-dimensionally computerized atlas of the human vocal organ using Visible Human male dataset. A self-developed program with C language and a recent personal computer can show specific organs and structures separately or together, rotate them at three axes, cross-section them transparently at any angles, and zoom them in and out. As a result, our own PC-based program will be a more interactive, more detailed, and more realistic three-dimensional computerized atlas of a human vocal organ including larygopharynx.

  14. Is the rapid post-mating inhibition of pheromone response triggered by ecdysteroids or other factors from the sex accessory glands in the male moth Agrotis ipsilon?

    PubMed

    Vitecek, Simon; Maria, Annick; Blais, Catherine; Duportets, Line; Gaertner, Cyril; Dufour, Marie-Cécile; Siaussat, David; Debernard, Stéphane; Gadenne, Christophe

    2013-05-01

    In many animals, male copulation is dependent on the detection and processing of female-produced sex pheromones, which is generally followed by a sexual refractory post-ejaculatory interval (PEI). In the male moth, Agrotis ipsilon, this PEI is characterized by a transient post-mating inhibition of behavioral and central nervous responses to sex pheromone, which prevents males from re-mating until they have refilled their reproductive tracts for a potential new ejaculate. However, the timing and possible factors inducing this rapid olfactory switch-off are still unknown. Here, we determined the initial time delay and duration of the PEI. Moreover, we tested the hypothesis that the brain, the testis and/or the sex accessory glands (SAGs) could produce a factor inducing the PEI. Lastly, we investigated the possible involvement of ecdysteroids, hormones essential for development and reproduction in insects, in this olfactory plasticity. Using brain and SAG cross-injections in virgin and newly-mated males, surgical treatments, wind tunnel behavioral experiments and EIA quantifications of ecdysteroids, we show that the PEI starts very shortly after the onset of copulation, and that SAGs contain a factor, which is produced/accumulated after copulation to induce the PEI. Moreover, SAGs were found to be the main source of ecdysteroids, whose concentration decreased after mating, whereas it increased in the haemolymph. 20-Hydroxyecdysone (20E) was identified as the major ecdysteroid in SAGs of A. ipsilon males. Finally, 20E injections did not reduce the behavioral pheromone response of virgin males. Altogether our data indicate that 20E is probably not involved in the PEI. PMID:23562716

  15. Counseling Males.

    ERIC Educational Resources Information Center

    Scher, Murray, Ed.

    1981-01-01

    Contains 16 articles about counseling males including: (1) gender role conflict; (2) sex-role development; (3) counseling adolescent, adult, and gay males; (4) teenage fathers; (5) female therapists and male clients; (6) career development; (7) hypermasculinity; (8) counseling physically abusive men, uncoupling men; (9) group therapy, men's…

  16. Co-occurrence of antisocial behavior and substance use: testing for sex differences in the impact of older male friends, low parental knowledge and friends' delinquency.

    PubMed

    McAdams, Tom A; Salekin, Randall T; Marti, C Nathan; Lester, Whiney S; Barker, Edward D

    2014-04-01

    Delinquency and substance use (SU) are commonly comorbid during adolescence. In the present study we investigate this co-morbidity with 3 main objectives: 1. Evaluate reciprocal relationships between delinquency/SU across early adolescence. 2. Assess the impact of older male friends, low parental knowledge and friends' delinquency on subsequent development and inter-relationships of delinquency and SU. 3. Evaluate sex differences in these relationships. We applied cross-lagged structural equation models to the analysis of a longitudinal sample (n=3699). Findings demonstrated: (1) At ages 13-14 delinquency predicted SU more so than vice versa but effects became equal between ages 14 and 15. (2) Low parental knowledge and friends' delinquency predicted delinquency and SU. Older male friends predicted ASB. (3) Sex differences were present. For example, in the absence of antisocial friends low parent knowledge at age 12 indirectly predicted increased age 15 SU for girls more than boys. PMID:24636685

  17. The Relationship of the Hooper Visual Organization Test to Sex, Age, and Intelligence of Elementary School Children.

    ERIC Educational Resources Information Center

    Hilgert, Larry D.; Treloar, James H.

    1985-01-01

    Administered the Hooper Visual Organization Test (VOT) to 54 elementary students referred for psychometric evaluation. Results showed no significant relationship between sex and VOT scores, but age and IQ were significant correlates. (JAC)

  18. Role of genetics and sex steroid hormones in male androgenetic alopecia and female pattern hair loss: an update of what we now know.

    PubMed

    Yip, Leona; Rufaut, Nick; Sinclair, Rod

    2011-05-01

    The role of genetic predisposition and the influence of sex steroid hormones are indisputable to the pathogenesis of male androgenetic alopecia (MAGA). The role of sex steroid hormones in female pattern hair loss (FPHL) is less known. A good knowledge of the pathophysiology underlying MAGA and FPHL empowers the clinician to confidently counsel patients and make informed therapeutic decisions. Vigorous research in recent years has provided greater insight into the role of genetics and sex steroids in physiological hair growth and cycling, as well as in hair follicle miniaturization, the histological hallmark of MAGA and FPHL. In the present review article directed towards clinicians, we discuss the current understanding of the role of androgens and oestrogens, as well as genetic associations with MAGA and FPHL. We also briefly discuss the interpretation of direct-to-consumer genetic testing for baldness to help clinicians understand the limitations of such tests. PMID:21605090

  19. Prevalence and correlates of HIV and sexually transmitted infections among female sex workers and their non-commercial male partners in two Mexico-USA border cities.

    PubMed

    Robertson, Angela M; Syvertsen, Jennifer L; Ulibarri, Monica D; Rangel, M Gudelia; Martinez, Gustavo; Strathdee, Steffanie A

    2014-08-01

    Female sex workers (FSWs) acquire HIV and other sexually transmitted infections (STIs) through unprotected sex with commercial and non-commercial (intimate) male partners. Little research has focused on FSWs' intimate relationships, within which condom use is rare. We sought to determine the prevalence and correlates of HIV/STIs within FSWs' intimate relationships in Northern Mexico. From 2010 to 2011, we conducted a cross-sectional survey of FSWs and their non-commercial male partners in Tijuana and Ciudad Juárez, Mexico. Eligible FSWs and their verified male partners were aged ?18 years; FSWs reported lifetime use of heroin, cocaine, crack, or methamphetamine and recently exchanged sex (past month). Participants completed baseline questionnaires and testing for HIV, chlamydia, gonorrhea, and syphilis. We determined the prevalence and correlates of individuals' HIV/STI positivity using bivariate probit regression. Among 212 couples (n?=?424), prevalence of HIV was 2.6 % (n?=?11). Forty-two (9.9 %) tested positive for any HIV/STIs, which was more prevalent among women than men (12.7 % vs. 7.1 %, p?sex work clients were less likely to test positive for HIV/STIs than those without regular clients. Similarly, male partners of FSWs who had regular clients were 9 % less likely to have HIV/STIs. Higher sexual decision-making power was protective against HIV/STIs for women. Men who recently used methamphetamine or reported perpetrating any conflict within steady relationships were more likely to test positive for HIV/STIs. Within FSWs' intimate relationships in two Mexican-US border cities, nearly one in ten partners tested positive for HIV/STIs. Couple-based prevention interventions should recognize how intimate relationship factors and social contexts influence HIV/STI vulnerability. PMID:24488651

  20. Recalled Sexual Experiences in Childhood with Older Partners: A Study of Brazilian Men Who Have Sex with Men and Male-to-Female Transgender Persons

    Microsoft Academic Search

    Alex Carballo-Diéguez; Ivan Balan; Curtis Dolezal; Maeve B. Mello

    This study assessed the prevalence of recalled childhood sexual experiences with an older partner among men who have sex with\\u000a men (MSM) and\\/or male-to-female transgender persons recruited in Campinas, Brazil. It also analyzed associations between such\\u000a recalled experiences and sexual risk behavior in adulthood. Participants recruited using respondent driven sampling completed\\u000a a self-administered, computer-based questionnaire, and underwent HIV testing. For

  1. A Comparison Between Exclusively Male Target and Female\\/Both Sexes Target Child Molesters on Psychometric Variables, DSM-IV Diagnoses and MTC:CM3 Typology

    Microsoft Academic Search

    Reinhard Eher; Christine Gruenhut; Stefan Fruehwald; Patrick Frottier; Brigitte Hobl; Martin Aigner

    2002-01-01

    Forty-eight men incarcerated for child molestation were divided into two groups on the basis of the gender of their victims: (1) exclusively male target and (2) female or both sexes target child molesters. Psychiatric comorbidity was measured using the Structured Clinical Interview for DSM-IV. Offenders were described in terms of the MTC:CM3 child molester typology, and they completed self-report instruments

  2. Explanations of successful performance on sex-linked tasks: What is skill for the male is luck for the female

    Microsoft Academic Search

    Kay Deaux; Tim Emswiller

    1974-01-01

    Instructed 55 male and 75 female undergraduates to evaluate the performance of either a male or female stimulus person who was heard to perform in an above-average manner on either a male- or female-related task. Analysis of the attributions made to luck vs skill in explaining the performance of the stimulus person showed that as predicted, performance by a male

  3. Selective Lineage Specification by Mab-19 during Caenorhabditis Elegans Male Peripheral Sense Organ Development

    PubMed Central

    Sutherlin, M. E.; Emmons, S. W.

    1994-01-01

    The action of the gene mab-19 is required for specification of a subset of Caenorhabditis elegans male peripheral sense organ (ray) lineages. Two mab-19 alleles, isolated in screens for ray developmental mutations, resulted in males that lacked the three most posterior rays. Cell lineage alterations of male-specific divisions of the most posterior lateral hypodermal (seam) blast cell, T, resulted in the ray loss phenotype in mab-19 mutant animals. Postembryonic seam lineage defects were limited to male-specific T descendent cell divisions. Embryonic lethality resulted when either mab-19 mutation was placed over a chromosomal deficiency encompassing the mab-19 locus. The earliest detectable defect was aberrant hypodermal cell movements during morphogenesis. From these data, it is inferred that both mab-19 alleles described are hypomorphs, and further reduction of mab-19 function results in embryos that are unable to complete morphogenesis. Thus, mab-19 may play a larger role in developmental regulation of hypodermal cell fate, including sensory ray development in males. Body morphology mutations, passage through the dauer stage, and heat or CdCl(2) treatment suppressed mab-19 male phenotypes. A model is presented in which all three types of suppression result in a physiological stress response, which in turn leads to correction of the mab-19 defect. PMID:7851765

  4. Debe cuidarse en la calle: normative influences on condom use among the steady male partners of female sex workers in the Dominican Republic.

    PubMed

    Barrington, Clare; Kerrigan, Deanna

    2014-02-21

    Encouragement to use condoms reflects the injunctive norm, or idea that you should use condoms. In our previous research with the regular male partners of female sex workers, in the Dominican Republic, we found that encouragement to use condoms with female sex workers from individuals in their personal social networks was not directly associated with condom use. In the current study, we used qualitative interviews to further explore the influence of social network norms on men's sexual-risk behaviours. We interviewed 11 steady male partners of female sex workers, with participants completing two interviews to achieve greater depth. We analysed data using analytic summaries and systematic thematic coding. All men perceived that the prevailing injunctive norm was that they should use condoms with sex workers. Men received encouragement to use condoms but did not articulate a link between this encouragement and condom use. Additionally, men who did not use condoms lied to their friends to avoid social sanction. Findings highlight that the influence of a pro-condom injunctive norm is not always health promoting and can even be negative. HIV-prevention efforts seeking to promote condom use should address the alignment between injunctive and descriptive norms to strengthen their collective influence on behaviour. PMID:24555440

  5. Species, sex, size and male maturity composition of previously unreported elasmobranch landings in Kuwait, Qatar and Abu Dhabi Emirate.

    PubMed

    Moore, A B M; McCarthy, I D; Carvalho, G R; Peirce, R

    2012-04-01

    This paper presents data from the first major survey of the diversity, biology and fisheries of elasmobranchs in the Persian (Arabian) Gulf. Substantial landings of elasmobranchs, usually as gillnet by-catch, were recorded in Kuwait, Qatar and the Emirate of Abu Dhabi (part of the United Arab Emirates), although larger elasmobranchs from targeted line fisheries were landed in Abu Dhabi. The elasmobranch fauna recorded was distinctive and included species that are undescribed, rare and have a highly restricted known distribution. Numerical abundance was dominated by sharks (c. 80%), of which carcharhinids were by far the most important. The milk shark Rhizoprionodon acutus and whitecheek shark Carcharhinus dussumieri together comprised just under half of all recorded individuals. Around 90% of recorded sharks were small (50-90 cm total length, L(T) ) individuals, most of which were mature individuals of species with a small maximum size (<100 cm L(T) ), although immature individuals of larger species (e.g. Carcharhinus sorrah and other Carcharhinus spp.) were also important. The most frequently recorded batoid taxa were cownose rays Rhinoptera spp., an undescribed whipray, and the granulated guitarfish Rhinobatos granulatus. The first size, sex and maturity data for a wide range of Gulf elasmobranch species are presented (including L(T) at 50% maturity for males of four shark species) and include some notable differences from other locations in the Indo-West Pacific Ocean. A number of concerns regarding the sustainability of the fishery were highlighted by this study, notably that most of the batoid species recorded are classed by the IUCN Red List as vulnerable, endangered, data deficient or not evaluated. Despite their considerable elasmobranch landings, none of the three countries sampled have developed a 'Shark Plan' as encouraged to do so under the FAO International Plan of Action: Sharks. Furthermore, Kuwait and Qatar currently report zero or no elasmobranch landings to the FAO. PMID:22497401

  6. Organ doses for reference adult male and female undergoing computed tomography estimated by Monte Carlo simulations

    SciTech Connect

    Lee, Choonsik; Kim, Kwang Pyo; Long, Daniel; Fisher, Ryan; Tien, Chris; Simon, Steven L.; Bouville, Andre; Bolch, Wesley E. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Department of Nuclear Engineering, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611 (United States); Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, Florida 32611 (United States)

    2011-03-15

    Purpose: To develop a computed tomography (CT) organ dose estimation method designed to readily provide organ doses in a reference adult male and female for different scan ranges to investigate the degree to which existing commercial programs can reasonably match organ doses defined in these more anatomically realistic adult hybrid phantomsMethods: The x-ray fan beam in the SOMATOM Sensation 16 multidetector CT scanner was simulated within the Monte Carlo radiation transport code MCNPX2.6. The simulated CT scanner model was validated through comparison with experimentally measured lateral free-in-air dose profiles and computed tomography dose index (CTDI) values. The reference adult male and female hybrid phantoms were coupled with the established CT scanner model following arm removal to simulate clinical head and other body region scans. A set of organ dose matrices were calculated for a series of consecutive axial scans ranging from the top of the head to the bottom of the phantoms with a beam thickness of 10 mm and the tube potentials of 80, 100, and 120 kVp. The organ doses for head, chest, and abdomen/pelvis examinations were calculated based on the organ dose matrices and compared to those obtained from two commercial programs, CT-EXPO and CTDOSIMETRY. Organ dose calculations were repeated for an adult stylized phantom by using the same simulation method used for the adult hybrid phantom. Results: Comparisons of both lateral free-in-air dose profiles and CTDI values through experimental measurement with the Monte Carlo simulations showed good agreement to within 9%. Organ doses for head, chest, and abdomen/pelvis scans reported in the commercial programs exceeded those from the Monte Carlo calculations in both the hybrid and stylized phantoms in this study, sometimes by orders of magnitude. Conclusions: The organ dose estimation method and dose matrices established in this study readily provides organ doses for a reference adult male and female for different CT scan ranges and technical parameters. Organ doses from existing commercial programs do not reasonably match organ doses calculated for the hybrid phantoms due to differences in phantom anatomy, as well as differences in organ dose scaling parameters. The organ dose matrices developed in this study will be extended to cover different technical parameters, CT scanner models, and various age groups.

  7. A comparison of male sex workers in Prague: Internet escorts versus men who work in specialized bars and clubs.

    PubMed

    Bar-Johnson, Michael David; Weiss, Petr

    2015-01-01

    Prague, the Czech Republic, is a popular sex tourism destination where sex work is decriminalized and young men offer sexual services at low prices relative to countries in Western Europe. This quantitative survey aimed to identify some of the demographic characteristics of these young men and their experiences in the sex industry. Internet escorts (N = 20) and sex workers in bars and clubs (N = 20) completed the survey anonymously in spring 2011. The results showed that sex workers in clubs often had troubled pasts and were forced into sex work to survive. They also reported incidents of violence, serious alcohol and drug use, as well as frequent gambling. The larger group of sex workers in Prague is made up of Internet escorts who have backgrounds that are not atypical for the average Czech youth. They had fewer problems with drugs and alcohol but were twice as likely as sex workers in bars and clubs to be victims of violent crime. Plans for interventions to help those who would change their line of work, as well as the importance of sociocultural context in understanding sex workers, are discussed. PMID:24423089

  8. Acceptability of vaginal microbicides among female sex workers and their intimate male partners in two Mexico-U.S. border cities: a mixed methods analysis

    PubMed Central

    Robertson, Angela M.; Syvertsen, Jennifer L.; Martinez, Gustavo; Rangel, M. Gudelia; Palinkas, Lawrence A.; Stockman, Jamila K.; Ulibarri, Monica D.; Strathdee, Steffanie A.

    2013-01-01

    Background Female sex workers (FSWs) may benefit from pre-exposure prophylaxis (PrEP) including microbicides for HIV prevention. Since adherence is a key factor in PrEP efficacy, we explored microbicide acceptability and potential barriers to use within FSWs’ intimate relationships in Tijuana and Ciudad Juárez, Mexico, where HIV prevalence is increasing. Methods FSWs and their verified intimate (non-commercial) male partners completed quantitative and qualitative interviews from 2010–2012. Our complementary mixed methods design followed an iterative process to assess microbicide acceptability, explore related relationship dynamics, and identify factors associated with concern about male partners’ anger regarding microbicide use. Results Among 185 couples (n=370 individuals), interest in microbicides was high. In qualitative interviews with 28 couples, most participants were enthusiastic about microbicides for sex work contexts but some explained that microbicides could imply mistrust/infidelity within their intimate relationships. In the overall sample, nearly 1 in 6 participants (16%) worried that male partners would become angry about microbicides, which was associated with higher self-esteem among FSWs and lower self-esteem and past year conflict causing injury within relationships among men. Conclusions HIV prevention interventions should consider intimate relationship dynamics posing potential barriers to PrEP acceptability and adherence, involve male partners, and promote risk communication skills. PMID:23398385

  9. On the Eyes of Male Coffee Berry Borers as Rudimentary Organs

    PubMed Central

    Vega, Fernando E.; Simpkins, Ann; Bauchan, Gary; Infante, Francisco; Kramer, Matthew; Land, Michael F.

    2014-01-01

    The coffee berry borer, Hypothenemus hampei, is the most damaging insect pest of coffee worldwide. Like males in other species in the genus, male coffee berry borers have a lower number of facets in the compound eyes than females. The rudimentary eyes in male coffee berry borers could be an evolutionary response to their cryptic life habit, whereby they are born inside a coffee berry and never leave the berry. The main objective of the study was to determine if the differences in the number of facets translates into differences in visual acuity. We used low-temperature scanning electron microscopy to visualize and quantify the number of facets in the compound eyes. There was a significantly lower (p<0.0001) number of facets in males (19.1±4.10) than in females (127.5±3.88). To assess visual acuity, we conducted optomotor response experiments, which indicate that females respond to movement, while males did not respond under the conditions tested. The coffee berry borer is an example of an insect whereby disuse of an organ has led to a rudimentary compound eye. This is the first study that has experimentally tested responses to movement in bark beetles. PMID:24465752

  10. On the eyes of male coffee berry borers as rudimentary organs.

    PubMed

    Vega, Fernando E; Simpkins, Ann; Bauchan, Gary; Infante, Francisco; Kramer, Matthew; Land, Michael F

    2014-01-01

    The coffee berry borer, Hypothenemus hampei, is the most damaging insect pest of coffee worldwide. Like males in other species in the genus, male coffee berry borers have a lower number of facets in the compound eyes than females. The rudimentary eyes in male coffee berry borers could be an evolutionary response to their cryptic life habit, whereby they are born inside a coffee berry and never leave the berry. The main objective of the study was to determine if the differences in the number of facets translates into differences in visual acuity. We used low-temperature scanning electron microscopy to visualize and quantify the number of facets in the compound eyes. There was a significantly lower (p<0.0001) number of facets in males (19.1 ± 4.10) than in females (127.5 ± 3.88). To assess visual acuity, we conducted optomotor response experiments, which indicate that females respond to movement, while males did not respond under the conditions tested. The coffee berry borer is an example of an insect whereby disuse of an organ has led to a rudimentary compound eye. This is the first study that has experimentally tested responses to movement in bark beetles. PMID:24465752

  11. Sex-specific parental care strategies via nestling age: females pay more attention to nestling demands than males do in the horned lark, Eremophila alpestris.

    PubMed

    Liu, Chang-Jing; Du, Bo; Liu, Nai-Fa; Bao, Shi-Jie; Zhang, Shengxiang

    2014-06-01

    In many species, nestling demands vary continuously during early development and both parents have different parental care strategies at each nestling age. Sexual conflict arises when each parent expects its partner investing more in parental care. It is largely unknown how the two parents respond to the dynamics of nestling demands and resolve the sexual conflict during nestling period, especially on Qinghai-Tibetan Plateau. To address this question, we monitored parental care behaviors of horned larks (Eremophila alpestris) using video-recording systems. We found that male horned larks invested less in parental care, but had a larger body size than females, which is consistent with the parental investment hypothesis. Only the female brooded nestlings, but both parents contributed to feeding efforts. Feeding rates of males and females were negatively correlated, indicating that they used evolutionarily stable strategies. Strategies of parental care via nestling age were sex-specific. Females continuously adjusted care behaviors to follow the dynamics of nestling demands as nestling age increased, such as decreasing brood attentiveness and increasing feeding rate. By contrast, male feeding rate showed no significant correlation with nestling age, but increased with the synchrony feeding rate. We suggest the synchrony feeding behavior may act as a control measure for females to promote and assess the males' contribution. We consider low mating opportunities drive males to act as assistants for females, and correspondingly cause males to pay less attention to nestling demands than females. PMID:24882094

  12. CO2 laser in treatment of condylomata acuminata of male reproductive organs

    NASA Astrophysics Data System (ADS)

    Wozniak, Jakub; Opala, Tomasz; Pisarska-Krawczyk, Magdalena; Wilczak, Maciej; Pisarski, Tadeusz

    1996-03-01

    The results of laser therapy in the treatment of condylomata acuminata of male reproductive organs are reported. Between November 1991 and February 1995 in the Department of Reproduction, Institute of Gynecology and Obstetrics, Karol Marcinkowski University School of Medical Sciences, Poznan in 28 patients with condylomatous changes of reproductive organs carbon-dioxide laser therapy under colposcopic control was done. In 24 of them the healing was achieved. In four patients second laser therapy was done. All patients are still under control in the Department of Reproduction and there was no recurrence diagnosed.

  13. Sex differences, effects of male presence and coordination of nest visits in prairie voles (Microtus ochrogaster) during the immediate postnatal period

    USGS Publications Warehouse

    Mcguire, B.; Parker, E.; Bemis, W.E.

    2007-01-01

    Little is known about sex differences in parental behavior of biparental mammals and if mates in such species coordinate care of young. We studied parental care displayed by prairie voles (Microtus ochrogaster) under seminatural laboratory conditions during the first 3 d of life of their offspring. Through direct observations and videotaping, we monitored members of male-female pairs to determine if sex differences in early parental behavior exist and if mothers and fathers coordinate visits to the nest. To assess the impact of fathers on survival of pups and behavior of mothers, we also examined parental care displayed by single females toward their young. Male and female members of breeding pairs differed dramatically in degree of parental care. Females spent more time in the nest with young and licked them more frequently than did males. Additionally, females maintained the nest more frequently than did males, whereas they maintained runways less frequently. Although coordination of visits to the nest was not perfect between members of pairs, pups of pairs were left alone for less time than were pups of single females. Parental behavior displayed by paired and single females did not differ, nor did survival of their young to day 3 or 15. We suggest that provision of ample space and cover to vole parents rearing young in captivity promotes expression of sex differences in parental behavior, but that even seminatural conditions are not sufficient to yield benefits of father presence to survival of young. Under more challenging conditions, such as cold temperatures or presence of predators, benefits of father presence might emerge.

  14. Cuelure but not zingerone make the sex pheromone of male Bactrocera tryoni (Tephritidae: Diptera) more attractive to females.

    PubMed

    Kumaran, Nagalingam; Hayes, R Andrew; Clarke, Anthony R

    2014-09-01

    In tephritid fruit flies of the genus Bactrocera Macquart, a group of plant derived compounds (sensu amplo 'male lures') enhance the mating success of males that have consumed them. For flies responding to the male lure methyl eugenol, this is due to the accumulation of chemicals derived from the male lure in the male rectal gland (site of pheromone synthesis) and the subsequent release of an attractive pheromone. Cuelure, raspberry ketone and zingerone are a second, related group of male lures to which many Bactrocera species respond. Raspberry ketone and cuelure are both known to accumulate in the rectal gland of males as raspberry ketone, but it is not known if the emitted male pheromone is subsequently altered in complexity or is more attractive to females. Using Bactrocera tryoni as our test insect, and cuelure and zingerone as our test chemicals, we assess: (i) lure accumulation in the rectal gland; (ii) if the lures are released exclusively in association with the male pheromone; and (iii) if the pheromone of lure-fed males is more attractive to females than the pheromone of lure-unfed males. As previously documented, we found cuelure was stored in its hydroxyl form of raspberry ketone, while zingerone was stored largely in an unaltered state. Small but consistent amounts of raspberry ketone and ?-(4-hydroxy-3-methoxyphenyl)-propionic acid were also detected in zingerone-fed flies. Males released the ingested lures or their analogues, along with endogenous pheromone chemicals, only during the dusk courtship period. More females responded to squashed rectal glands extracted from flies fed on cuelure than to glands from control flies, while more females responded to the pheromone of calling cuelure-fed males than to control males. The response to zingerone treatments in both cases was not different from the control. The results show that male B. tryoni release ingested lures as part of their pheromone blend and, at least for cuelure, this attracts more females. PMID:25010549

  15. Involvement in Specific HIV Risk Practices among Men Who Use the Internet to Find Male Partners for Unprotected Sex

    PubMed Central

    2013-01-01

    Purpose. Men who have sex with other men (MSM) account for more than one-half of all new HIV infections in the USA. This study reports on the prevalence of a variety of HIV risk behaviors in one specific subpopulation of risk-seeking MSM. Methods. The study was based on a national sample of 332 MSM who use the Internet to find partners for unprotected sex. Data collection was conducted via telephone interviews between January 2008 and May 2009. Results. Unprotected oral and anal sex was commonplace among study participants. Men engaged in a large number of other risky behaviors as well, including having had multiple recent sex partners (mean number = 11), simultaneous double-penile penetration of the anus (16%), eating semen out of another man's anus (17%), engaging in multiple-partner sexual encounters (47%), engaging in anonymous sex (51%), and having sex while “under the influence” (52%). Conclusions. HIV intervention and prevention programs need to address numerous behaviors that place MSM at risk for contracting/transmitting HIV. Merely focusing on unprotected anal sex does a disservice to members of this community, who typically engage in many types of behavioral risks, each of which requires addressing if HIV transmission rates are to be reduced. PMID:24826369

  16. Safe sex: male–female coalitions and pre-copulatory mate-guarding in a fiddler crab

    PubMed Central

    Milner, Richard N. C.; Jennions, Michael D.; Backwell, Patricia R. Y.

    2010-01-01

    In fiddler crabs both males and females defend territories that are essential for survival. Given pronounced sexual dimorphism in weaponry, how do weaponless females defend their territory from well-armed males? Using observational data and two simple experiments, we test whether male Uca annulipes protect their female neighbours from conspecific intruders. We show that males defend their female neighbours against male but not female intruders. We also show that females sometimes mate with their immediate neighbours. Male defence of female neighbours appears to represent both pre-copulatory mate-guarding and a territorial coalition. Males who ensure that their neighbour remains female could benefit through increased opportunity for future reproductive success and lower boundary maintenance costs. PMID:19889695

  17. The postnatal development of the sex organs in prenatally and early postnatally irradiated male albino rats

    E-print Network

    Ricks, Robert Clinton

    1964-01-01

    42. 6c bc 36 6abc 4i ib'd 38 7abcd ?Means with the same superscript do not differ at the 5g level of significance as determined by Kramer's modification of Duncan's Multiple Range Test. 25 and were significantly lighter than those...

  18. Synergistic Effect of Fadrozole and Insulin-Like Growth Factor-I on Female-To-Male Sex Reversal and Body Weight of Broiler Chicks

    PubMed Central

    Mohammadrezaei, Mohammad; Toghyani, Majid; Gheisari, Abbasali; Toghyani, Mehdi; Eghbalsaied, Shahin

    2014-01-01

    The aim of this study was to investigate the effects of Fadrozole hydrochloride and recombinant human insulin-like growth factor I (rhIGF-I) on female-to-male sex reversal, hatching traits, and body weight of broiler chickens. On the third day of incubation, fertile eggs were randomly assigned to five experimental groups comprising (i) Fadrozole (0.1 mg/egg), (ii) rhIGF-I (100 ng/egg), (iii) Fadrozole (0.1 mg/egg) + rhIGF-I (100 ng/egg), (iv) vehicle injection (10 mM acetic acid and 0.1% BSA), and (v) non-injected eggs. Eggs in the rhIGF-I-injected groups showed the mode of hatching time at the 480th hour of incubation, 12 hours earlier compared to the other groups, with no statistically significant difference in mortality and hatchability. On Day 1 and 42 of production, 90% of genetically female chicks were masculinized using Fadrozole treatment, while 100% female-to-male phenotypic sex reversal was observed in the Fadrozole+rhIGF-I group. Fadrozole equalized the body weight of both genders, although rhIGF-I was effective on the body weight of male chicks only. Interestingly, combined rhIGF-I and Fadrozole could increase the body weight in both sexes compared to the individual injections (P<0.05). These findings revealed that (i) IGF-I-treated chicken embryos were shown to be an effective option for overcoming the very long chicken deprivation period, (ii) the simultaneous treatment with Fadrozole and IGF-I could maximize the female-to-male sex reversal chance, (iii) the increase in the body weight of masculinized chickens via Fadrozole could be equal to their genetically male counterparts, and (iv) the IGF-I effectiveness, specifically along with the application of aromatase inhibitors in female chicks, indicates that estrogen synthesis could be a stumbling block for the IGF-I action mechanism in female embryos. PMID:25075864

  19. Circuits attenuating seizures under well-fed and food-deprived conditions in C. elegans male sex muscles 

    E-print Network

    Leboeuf, Brigitte L.

    2010-07-14

    or not at all, vulva penetration and thus successful mating will not occur. In this dissertation, I elucidate the circuits regulating sex-muscle excitability under standard conditions and describe how these pathways are augmented to further reduce excitability...

  20. Chemical composition of scent-gland secretions in an old world monkey (Mandrillus sphinx): influence of sex, male status, and individual identity.

    PubMed

    Setchell, Joanna M; Vaglio, Stefano; Moggi-Cecchi, Jacopo; Boscaro, Francesca; Calamai, Luca; Knapp, Leslie A

    2010-03-01

    Primates are traditionally considered to be microsmatic, with decreased reliance on olfactory senses in comparison to other sensory modalities such as vision. This is particularly the case for Old World monkeys and apes (catarrhines). However, various lines of evidence suggest that chemical communication may be important in these species, including the presence of a sternal scent-gland in the mandrill. We investigated the volatile components of mandrill odor using gas chromatography-mass spectrometry. We identified a total of 97 volatile components in 88 swabs of the sternal gland secretion and 95 samples of sternal gland hair saturated with scent-gland secretion collected from 27 males and 18 females. We compared odor profiles with features of the signaler using principle components and discriminant function analyses and found that volatile profiles convey both variable (age, dominance rank in males) and fixed (sex, possibly individual identity) information about the signaler. The combination of an odor profile that signals sex, age, and rank with increased motivation to scent-mark and increased production of secretion in high-ranking males leads to a potent signal of the presence of a dominant, adult male with high testosterone levels. This may be particularly relevant in the dense Central African rain forest which mandrills inhabit. By contrast, we were unable to differentiate between either female cycle stage or female rank based on odor profiles, which accords with behavioral studies suggesting that odor signals are not as important in female mandrills as they are in males. The similarity of our findings to those for other mammals and in primates that are more distantly related to humans suggests a broader role for odor in primate communication than is currently recognized. PMID:20089603

  1. Inconsistent condom use by male clients during anal intercourse with occasional and regular female sex workers (FSWs): survey findings from southern states of India

    PubMed Central

    Ramanathan, Shreena; Nagarajan, Karikalan; Ramakrishnan, Lakshmi; Mainkar, Mandar K; Goswami, Prabuddhagopal; Yadav, Diwakar; Sen, Shrabanti; George, Bitra; Rachakulla, Harikumar; Subramanian, Thilakavathi; Paranjape, Ramesh S

    2014-01-01

    Objectives Self-reported anal intercourse by female sex workers (FSWs) documented in recent studies from India range between 11.9% and 22%. However, comparable data on anal intercourse and condom use from male clients of FSWs is lacking. Using data from a bio-behavioural survey (2009–2010), we examined prevalence of anal intercourse, male clients’ self-reported inconsistent condom use during anal intercourse with FSWs, and correlates of this behaviour in India's high HIV prevalence southern states (Andhra Pradesh, Maharashtra and Tamil Nadu combined). Methods Using two-stage time location cluster sampling, we recruited 4803 clients of FSWs, ages 18–60?years, who had purchased sex from an FSW in the past month. After obtaining informed consent, respondents were interviewed and tested for HIV and sexually transmitted infections (syphilis, gonorrhoea and chlamydia). Logistic regression analysis was used to identify the factors associated with inconsistent condom use during anal intercourse (in the past 6?months) with FSWs. Results Overall, 12.3% clients reported anal intercourse in the past 6?months, of whom 48.4% used condoms inconsistently. Clients of FSWs who were ages 26?years or older (AOR 2.68, p=0.032); employed as manual labourers (AOR 2.43, p=0.013); consumed alcohol (AOR 2.63, p=0.001); reported five or more sex acts with FSWs in the past month (AOR 2.53, p=0.031); and perceived themselves to be at higher risk for HIV (AOR 4.82, p=0.001) were more likely to inconsistently use condoms during anal intercourse. Conclusions The results suggest that sex workers and their clients commonly practice anal intercourse, but a relatively high proportion of clients do not consistently use condoms, leading to a greater risk of acquiring HIV and its further transmission to other male and female sexual partners. Given the multidirectional risk, safer sex communication on heterosexual anal intercourse must be incorporated into HIV prevention programmes. PMID:25410604

  2. Sex differences in a mouse model of multiple sclerosis: neuropathic pain behavior in females but not males and protection from neurological deficits during proestrus

    PubMed Central

    2014-01-01

    Background Multiple sclerosis (MS), a demyelinating disease of the central nervous system, is one of the most prevalent neurological disorders in the industrialized world. This disease afflicts more than two million people worldwide, over two thirds of which are women. MS is typically diagnosed between the ages of 20–40 and can produce debilitating neurological impairments including muscle spasticity, muscle paralysis, and chronic pain. Despite the large sex disparity in MS prevalence, clinical and basic research investigations of how sex and estrous cycle impact development, duration, and severity of neurological impairments and pain symptoms are limited. To help address these questions, we evaluated behavioral signs of sensory and motor functions in one of the most widely characterized animal models of MS, the experimental autoimmune encephalomyelitis (EAE) model. Methods C57BL/6 male and female mice received flank injection of complete Freund’s adjuvant (CFA) or CFA plus myelin oligodendrocyte glycoprotein 35-55 (MOG35-55) to induce EAE. Experiment 1 evaluated sex differences of EAE-induced neurological motor deficits and neuropathic pain-like behavior over 3 weeks, while experiment 2 evaluated the effect of estrous phase in female mice on the same behavioral measures for 3 months. EAE-induced neurological motor deficits including gait analysis and forelimb grip strength were assessed. Neuropathic pain-like behaviors evaluated included sensitivity to mechanical, cold, and heat stimulations. Estrous cycle was determined daily via vaginal lavage. Results MOG35-55-induced EAE produced neurological impairments (i.e., motor dysfunction) including mild paralysis and decreases in grip strength in both females and males. MOG35-55 produced behavioral signs of neuropathic pain—mechanical and cold hypersensitivity—in females, but not males. MOG35-55 did not change cutaneous heat sensitivity in either sex. Administration of CFA or CFA?+?MOG35-55 prolonged the time spent in diestrus for 2 weeks, after which normal cycling returned. MOG35-55 produced fewer neurological motor deficits when mice were in proestrus relative to non-proestrus phases. Conclusions We conclude that female mice are superior to males for the study of neuropathic pain-like behaviors associated with MOG35-55-induced EAE. Further, proestrus may be protective against EAE-induced neurological deficits, thus necessitating further investigation into the impact that estrous cycle exerts on MS symptoms. PMID:24581045

  3. Men who report recent male and female sex partners in Cape Town, South Africa: an understudied and underserved population.

    PubMed

    Eaton, Lisa A; Pitpitan, Eileen V; Kalichman, Seth C; Sikkema, Kathleen J; Skinner, Donald; Watt, Melissa H; Pieterse, Desiree

    2013-10-01

    The HIV/AIDS epidemic in South Africa has largely focused on the needs of heterosexual men and women. However, little is known about the sexual risk histories of men who have sex with both men and women (MSMW). Furthermore, we know very little about the psychosocial health needs or of the possibility of a syndemic (numerous interrelated epidemics) among MSMW. We surveyed 1,203 men attending drinking establishments in a township located in Cape Town, South Africa. We compared the behaviors and experiences of MSMW to men reporting only having sex with women (MSW). Twelve percent of the sample reported having sex with both men and women in the past 4 months. MSMW were twice as likely as MSW to report being HIV positive (10.5 vs. 4.6 %). MSW were more likely to be married than MSMW but reported similar numbers of female sex partners. MSMW were more likely to report a history of childhood sexual abuse, recent experienced and perpetrated physical and sexual partner violence, both receiving and giving sex for money, drugs, or shelter, and a recent STI. These factors were found to be interrelated among MSW but not MSMW. Although MSMW demonstrate considerable risk taking and report higher rates of HIV infection than MSW, their needs are largely unmet and underemphasized. Findings suggest the need to better understand factors contributing to sexual risk taking among MSMW. HIV prevention interventions should consider psychosocial health problems unique to MSMW residing in South African townships. PMID:23519592

  4. Black Male-Female Suicide: A Case Study of Occupation and Rates of Suicide by Race and Sex.

    ERIC Educational Resources Information Center

    Taylor, Maurice C.

    1982-01-01

    Examines effects of labor force participation on Black and White suicide. Criticizes theories that focus on fatalism and erosion of the Black family and suggests that occupation, the same factor that accounts for White male suicide rates, contributes heavily to an explanation of Black male and female suicide rates. (Author/MJL)

  5. Sex reassignment of transsexual people from a gynecologist's and urologist's perspective.

    PubMed

    Trum, Hans W; Hoebeke, Piet; Gooren, Louis J

    2015-06-01

    Cross-sex hormone treatment of transgender persons is usually uneventful, but hormone-sensitive malignancies of the (reproductive) organs of the natal and new sex (breasts, neovagina) may arise. Sex reassignment surgery impacts on the urodynamics of the reassigned sex. Pathology originating from organ systems of the natal sex may be overlooked in the new sex. In male-to-female transgender individuals, malignant tumors of the breasts and prostate may occur. Neovaginas are constructed with skin or sigmoid. Shortening of the male urethra to female dimensions is usually uneventful. In female-to-male transgender individuals breast cancer may develop, sometimes in residual mammary tissue after reductive mammoplasty. Malignancies of the vagina and ovaries are rare. Testosterone may be aromatized to estrogens, with effects on the endometrium. Lengthening of the female urethra to male dimensions may cause urethral fistulae, urethral strictures, and meatal stenoses. A degree of post-voiding incontinence may occur. PMID:25721104

  6. Testosterone-dependent induction of metallothionein in genital organs of male rats.

    PubMed Central

    Tohyama, C; Suzuki, J S; Homma, S; Karasawa, M; Kuroki, T; Nishimura, H; Nishimura, N

    1996-01-01

    Metallothioneins (MTs) are a group of cysteine-rich heavy-metal-binding proteins. We have investigated MT gene expression in the ventral and dorsolateral lobes of the prostate and coagulating gland of male Wistar rats. In intact rats, both MT mRNA and MT were present in the dorsolateral lobe and coagulating gland but not in the ventral lobe. Orchidectomy caused involution of the above organs, and both MT mRNA and MT were considerably decreased or become undetectable. An injection of testosterone propionate into orchidectomized rats restored not only the size of these organs, but also MT mRNA and MT concentrations, particularly in the dorsolateral lobe and coagulating gland. In the dorsolateral lobe, no selective uptake of Zn2+ preceding the increase in MT was observed, suggesting that Zn2+ ions are not associated with the increased expression of the MT gene. The present result suggests that of the male auxiliary genital organs, the dorsolateral lobe and coagulating gland, but not the ventral lobe, contain MT, the biosynthesis of which is regulated by testosterone. PMID:8694792

  7. Exploration of functional health, mental well-being and cross-sex hormone use in a sample of Thai male-to-female transgendered persons (kathoeys)

    PubMed Central

    Gooren, Louis J; Sungkaew, Tanapong; Giltay, Erik J

    2013-01-01

    Transgender people sometimes use cross-sex hormones without medical supervision. The use of cross-sex hormones, as well as the functional health and mental well-being, among male-to-female transgendered people (‘kathoeys') in Chiang Mai, Thailand, was studied. Sixty kathoeys were interviewed regarding their use of cross-sex hormones and their family relationships. Individuals also completed the Life Orientation Test Revised (LOT-R) to assess dispositional optimism, the Social Functioning Questionnaire (SFQ) and the Short Form Health Survey 36 (SF-36). Three categories were established as follows: those who never cross-dress, those who sometimes cross-dress and those who always cross-dress in public. Of the 60 subjects, 44 had used hormones for prolonged periods (9.7±6.1 years). Their use was related to the permanence of cross-dressing but unrelated to functional health and mental well-being. Fifty percent of subjects had overdosed on commonly used oral contraceptives. Three people used injectable oestrogen in a higher-than-recommended dose. Self-acceptance was high or reasonably good (83%) compared to no acceptance (17%), and neither was related to the permanence of cross-dressing. Their acceptance by parents and siblings was also relatively high (85% and 89%, respectively). The permanence of cross-dressing had no effect on the scores of optimism, SF-36 scores and social functioning. Acceptance by oneself or one's parents did not seem to affect most aspects of functional health and mental well-being, but non-acceptance by siblings generated lower scores on the social functioning and general mental health subscales. Stressors tended to include physical rather than social factors. In conclusion, the unsupervised use of cross-sex hormones was common among kathoeys, and 50% of the sample had overdosed on them. Acceptance was relatively good, except by siblings. New strategies are needed for a more responsible use of cross-sex hormones. PMID:23353716

  8. Female brown-headed cowbirds', Molothrus ater, organization and behaviour reflects male social dynamics

    Microsoft Academic Search

    Meredith J. West; David J. White; Andrew P. King

    2002-01-01

    In four large aviaries, we studied social assortment and reproductive behaviour of female brown-headed cowbirds housed with males differing in age class and in corresponding levels of intrasexual interaction. Juvenile and adult females resided with either (1) adult males, (2) juvenile males, (3) adult and juvenile males, or (4) no males. We observed social behaviour of males and females from

  9. Sex workers self-organizing and empowerment : the experience of Women’s Network for Unity (WNU) in Cambodia : article produced as part of the KIC Project

    Microsoft Academic Search

    Womyn's Agenda for Change

    2007-01-01

    Many organizations that are working with sex workers have learned that it is ineffective to provide HIV and other health services to them if they do not consider – and address – sex workers’ work environments, where many cases of human rights violations can be found. Thus, they gradually move into rights-based activities. By reframing sex workers’ health as a

  10. Sex Determination and Sex Chromosomes Differentiation Between Different Sexes Occurs Even in ________________________.

    E-print Network

    Cutler, Chris

    Sex Determination and Sex Chromosomes Differentiation Between Different Sexes Occurs Even Determination Some of these Genes are on the Sex Chromosomes but Others are ____________ . In Multi Chromosome) = Male Sex Chromosomes The role of in Sex Determination was Initially Discovered Early in the 20

  11. A Sex Difference in the Predisposition for Physical Competition: Males Play Sports Much More than Females Even in the Contemporary U.S

    PubMed Central

    Deaner, Robert O.; Geary, David C.; Puts, David A.; Ham, Sandra A.; Kruger, Judy; Fles, Elizabeth; Winegard, Bo; Grandis, Terry

    2012-01-01

    Much evidence indicates that men experienced an evolutionary history of physical competition, both one-on-one and in coalitions. We thus hypothesized that, compared to girls and women, boys and men will possess a greater motivational predisposition to be interested in sports, especially team sports. According to most scholars, advocacy groups, and the United States courts, however, this hypothesis is challenged by modest sex differences in organized school sports participation in the contemporary U.S., where females comprise 42% of high school participants and 43% of intercollegiate participants. We conducted three studies to test whether organized school sports participation data underestimate the actual sex difference in sports participation. Study 1 analyzed the American Time Use Survey, which interviewed 112,000 individuals regarding their activities during one day. Females accounted for 51% of exercise (i.e., non-competitive) participations, 24% of total sports participations, and 20% of team sports participations. These sex differences were similar for older and younger age groups. Study 2 was based on systematic observations of sports and exercise at 41 public parks in four states. Females accounted for 37% of exercise participations, 19% of individual sports participations, and 10% of team sports participations. Study 3 involved surveying colleges and universities about intramural sports, which primarily consist of undergraduate participation in team sports. Across 34 institutions, females accounted for 26% of registrations. Nine institutions provided historical data, and these did not indicate that the sex difference is diminishing. Therefore, although efforts to ensure more equitable access to sports in the U.S. (i.e., Title IX) have produced many benefits, patterns of sports participation do not challenge the hypothesis of a large sex difference in interest and participation in physical competition. PMID:23155459

  12. Evaluation of a school-based sex education program for low income male high school students in Chile

    Microsoft Academic Search

    Mónica Silva; Inés Ross

    2003-01-01

    A sex education program was evaluated in a vocational high school in Santiago, Chile, that caters to a population of low income students. The goals of the program were to delay the occurrence of sexual activity, promote a positive attitude towards abstinence in adolescence, and facilitate communication on sexual topics with adults. A cohort design with no treatment partitioning was

  13. Early male partnership patterns, social support, and sexual risk behavior among young men who have sex with men.

    PubMed

    Glick, Sara Nelson; Golden, Matthew R

    2014-08-01

    Few data exist on the early sexual behavior patterns of contemporary young men who have sex with men (YMSM), the social context of these patterns, and which of these factors influence risk for HIV and other sexually transmitted infections (STI). We enrolled 94 YMSM (age 16-30) into a 1-year cohort study with serial online retrospective surveys and HIV/STI testing. The first three partnerships of YMSM were characterized by relatively high rates of unprotected anal sex and a rapidly expanding sexual repertoire, but also increasing rates of HIV status disclosure. During follow-up, 17 % of YMSM reported any nonconcordant unprotected anal intercourse (NCUAI) and 15 % were newly diagnosed with HIV/STI. Sex education in high school and current maternal support were protective against HIV/STI, while isolation from family and friends was associated with recent NCUAI. Social support-including from parents, peers, and school-based sex education-may help mitigate HIV/STI risk in this population. PMID:24356869

  14. Effect of sex hormones on the immune system of guinea-pigs and on the development of toxoplasmic lesions in non-lymphoid organs.

    PubMed Central

    Kittas, C; Henry, L

    1979-01-01

    The role of cell-mediated immunity in the pathogenesis of toxoplasmic lesions in non-lymphoid organs and its significance in resistance to infection with Toxoplasma gondii were studied in guinea-pigs. Alteration of the sex hormonal environment in both sexes has significant effects on the immunological status of the guinea-pig, changing its reaction to toxoplasmic infection. Thus, gonadectomy appears to enhance delayed hypersensitivity, leading to a greater prominence of lesions in the non-lymphoid organs of gonadectomized male and female animals than in controls. This observation supports the possibility that delayed hypersensitivity plays a major role in the pathogenesis of non-lymphoid, toxoplasmic lesions. Hexoestrol administration for a long period of time induces complete thymic atrophy and severe involution of the thymus-dependent areas of the lymph nodes and spleen, leading to the suppression of cell-mediated immunity and overwhelming disease in those animals infected with Toxoplasma gondii, suggesting that cell-mediated immunity is of importance in resistance to toxoplasmic infection. In view of these findings, the difficulties in the treatment of non-lymphoid toxoplasmic lesions, such as ocular ones, by depressing cellular immunity, are discussed. Images FIG. 1 FIG. 2 FIG. 3 FIG. 4 PMID:466859

  15. Gene content, organization and molecular evolution of plant organellar genomes and sex chromosomes: insights from the case of the liverwort Marchantia polymorpha.

    PubMed

    Ohyama, Kanji; Takemura, Miho; Oda, Kenji; Fukuzawa, Hideya; Kohchi, Takayuki; Nakayama, Sigeki; Ishizaki, Kimitsune; Fujisawa, Masaki; Yamato, Katsuyuki

    2009-01-01

    The complete nucleotide sequence of chloroplast DNA (121,025 base pairs, bp) from a liverwort, Marchantia polymorpha, has made clear the entire gene organization of the chloroplast genome. Quite a few genes encoding components of photosynthesis and protein synthesis machinery have been identified by comparative computer analysis. We also determined the complete nucleotide sequence of the liverwort mitochondrial DNA and deduced 96 possible genes in the sequence of 186,608 bp. The complete chloroplast genome encodes twenty introns (19 group II and 1 group I) in 18 different genes. One of the chloroplast group II introns separates a ribosomal protein gene in a trans-position. The mitochondrial genome contains thirty-two introns (25 group II and 7 group I) in the coding regions of 17 genes. From the evolutionary point of view, we describe the origin of organellar introns and give evidence for vertical and horizontal intron transfers and their intragenomic propagation. Furthermore, we describe the gene organization of the Y chromosome in the dioecious liverwort M. polymorpha, the first detailed view of a Y chromosome in a haploid organism. On the 10 megabase (Mb) Y chromosome, 64 genes are identified, 14 of which are detected only in the male genome. These 14 genes are expressed in reproductive organs but not in vegetative thalli, suggesting their participation in male reproductive functions. These findings indicate that the Y and X chromosomes share the same ancestral autosome and support the prediction that in a haploid organism essential genes on sex chromosomes are more likely to persist than in a diploid organism. PMID:19282647

  16. Dynamics of the HIV epidemic in southern China: sexual and drug-using behaviours among female sex workers and male clients in Yunnan

    PubMed Central

    Xu, J J; Smith, M K; Chu, J; Ding, G W; Chang, D F; Sharp, G B; Qian, H Z; Lu, L; Bi, A M; Wang, N

    2015-01-01

    Summary To examine the HIV/sexually transmitted infection (STI)-related risk behaviours among community-based female sex workers (FSWs) and their clients in Yunnan Province, China, we performed a cross-sectional study of 705 FSWs and 100 male clients. We found that HIV seroprevalence among FSWs was 13.0% and the most prevalent STI was herpes simplex virus type 2 (HSV-2) (71.1%), followed by Chlamydia trachomatis (18.1%) and syphilis (8.8%). The 20% of FSWs who reported injection drug use also reported needle-sharing behaviours in the last three months. Drug-using FSWs had substantially higher HIV and HSV-2 prevalence, serviced more clients and had a longer history of sex work than non-using FSWs. In total, 57.0% of male clients did not consistently use condoms with FSWs, 2.0% reported illicit drug use and 17.0% had STI symptoms in the last year. The dual risk behaviours of drug-using FSWs and clients place them at greater risk of HIV infection. Intervention programmes must adopt comprehensive methods. PMID:23033525

  17. The male sex pheromone darcin stimulates hippocampal neurogenesis and cell proliferation in the subventricular zone in female mice

    PubMed Central

    Hoffman, Emma; Pickavance, Lucy; Thippeswamy, Thimmasettappa; Beynon, Robert J.; Hurst, Jane L.

    2015-01-01

    The integration of newly generated neurons persists throughout life in the mammalian olfactory bulb and hippocampus, regions involved in olfactory and spatial learning. Social cues can be potent stimuli for increasing adult neurogenesis; for example, odors from dominant but not subordinate male mice increase neurogenesis in both brain regions of adult females. However, little is known about the role of neurogenesis in social recognition or the assessment of potential mates. Dominant male mice scent-mark territories using urine that contains a number of pheromones including darcin (MUP20), a male-specific major urinary protein that stimulates rapid learned attraction to the spatial location and individual odor signature of the scent owner. Here we investigate whether exposure to darcin stimulates neurogenesis in the female brain. Hippocampal neurons and cellular proliferation in the lateral ventricles that supply neurons to the olfactory bulbs increased in females exposed for 7 days to male urine containing at least 0.5 ?g/?l darcin. Darcin was effective whether presented alone or in the context of male urine, but other information in male urine appeared to modulate the proliferative response. When exposed to urine from wild male mice, hippocampal proliferation increased only if urine was from the same individual over 7 days, suggesting that consistency of individual scent signatures is important. While 7 days exposure to male scent initiated the first stages of increased neurogenesis, this caused no immediate increase in female attraction to the scent or in the strength or robustness of spatial learning in short-term conditioned place preference tests. The reliable and consistent stimulation of neurogenesis by a pheromone important in rapid social learning suggests that this may provide an excellent model to explore the relationship between the integration of new neurons and plasticity in spatial and olfactory learning in a socially-relevant context. PMID:25972792

  18. Behavioral responses of male turnip moths, Agrotis segetum , to sex pheromone in a flight tunnel and in the field

    Microsoft Academic Search

    Christer Löfstedt; Charles E. Linn; Jan Löfqvist

    1985-01-01

    The response of individual male turnip mothsAgrotis segetum was observed in a sustained flight tunnel to a mixture of decyl acetate, (Z)-5-decenyl acetate, (Z)-7-dodecenyl acetate, and (Z)-9-tetradecenyl acetate in proportions similar to those found in gland extracts from virgin females (0.6: 1:5:2.5). Lures containing 3–30 µg (Z)-5-decenyl acetate proved to be maximally attractive, with approximately 60% of the males completing

  19. Sex-dependent selection on an autosomal melanic female ornament promotes the evolution of sex ratio bias.

    PubMed

    Roulin, Alexandre; Altwegg, Res; Jensen, Henrik; Steinsland, Ingelin; Schaub, Michael

    2010-05-01

    Sex-dependent selection often leads to spectacularly different phenotypes in males and females. In species in which sexual dimorphism is not complete, it is unclear which benefits females and males derive from displaying a trait that is typical of the other sex. In barn owls (Tyto alba), females exhibit on average larger black eumelanic spots than males but members of the two sexes display this trait in the same range of possible values. In a 12-year study, we show that selection exerted on spot size directly or on genetically correlated traits strongly favoured females with large spots and weakly favoured males with small spots. Intense directional selection on females caused an increase in spot diameter in the population over the study period. This increase is due to a change in the autosomal genes underlying the expression of eumelanic spots but not of sex-linked genes. Female-like males produced more daughters than sons, while male-like females produced more sons than daughters when mated to a small-spotted male. These sex ratio biases appear adaptive because sons of male-like females and daughters of female-like males had above-average survival. This demonstrates that selection exerted against individuals displaying a trait that is typical of the other sex promoted the evolution of specific life history strategies that enhance their fitness. This may explain why in many organisms sexual dimorphism is often not complete. PMID:20337696

  20. Inhibitory effects of technical grade methoxychlor on development of neonatal male mouse reproductive organs.

    PubMed

    Cooke, P S; Eroschenko, V P

    1990-03-01

    Effects of technical grade methoxychlor (MX), an estrogenic insecticide, and 17 beta-estradiol (E2) were examined on serum testosterone (T) concentrations and growth and histology of neonatal male mouse reproductive organs. Male NIH/Swiss mice received i.p. injections daily from birth to Day 9 with one of the following: 10 micrograms E2 or 0.1 or 1.0 mg MX or sesame oil vehicle. The mice were killed on Day 10. MX or did not affect body weights or mortality. Serum T concentrations in control mice were 0.29 +/- 0.03 ng/ml; T concentrations in males treated with MX or E2 were reduced. The 1.0-mg dose of both MX and E2 significantly decreased DNA contents of the seminal vesicles (SV), bulbourethral glands (BUG), and ventral prostate (VP) compared to controls. In the same animals, DNA contents of testes, epididymides, and efferent ductules were not decreased. The lower dose of MX (0.1 mg) decreased DNA content of only BUG and SV. DNA content of the ductus deferens was not affected by any treatment. E2 and both doses of MX also decreased epithelial morphogenesis in the SV and BUG, and inhibited the onset of mucin production in BUG epithelium and smooth muscle differentiation in the ductus deferens. In summary, our results indicate that technical grade MX, at doses as low as 0.1 mg/day, and E2 inhibit neonatal male reproductive tract development and decrease serum T concentrations. PMID:2340338

  1. Can Sex Differences in Science Be Tied to the Long Reach of Prenatal Hormones? Brain Organization Theory, Digit Ratio (2D/4D), and Sex Differences in Preferences and Cognition

    PubMed Central

    Valla, Jeffrey; Ceci, Stephen J.

    2011-01-01

    Brain organization theory posits a cascade of physiological and behavioral changes initiated and shaped by prenatal hormones. Recently, this theory has been associated with outcomes including gendered toy preference, 2D/4D digit ratio, personality characteristics, sexual orientation, and cognitive profile (spatial, verbal, and mathematical abilities). We examine the evidence for this claim, focusing on 2D/4D and its putative role as a biomarker for organizational features that influence cognitive abilities/interests predisposing males toward mathematically and spatially intensive careers. Although massive support exists for early brain organization theory overall, there are myriad inconsistencies, alternative explanations, and outright contradictions that must be addressed while still taking the entire theory into account. Like a fractal within the larger theory, the 2D/4D hypothesis mirrors this overall support on a smaller scale while likewise suffering from inconsistencies (positive, negative, and sex-dependent correlations), alternative explanations (2D/4D related to spatial preferences rather than abilities per se), and contradictions (feminine 2D/4D in men associated with higher spatial ability). Using the debate over brain organization theory as the theoretical stage, we focus on 2D/4D evidence as an increasingly important player on this stage, a demonstrative case in point of the evidential complexities of the broader debate, and an increasingly important topic in its own right. PMID:22164187

  2. High prevalence of HIV and sexually transmitted infections among male sex workers in Abidjan, Côte d'Ivoire: need for services tailored to their needs

    PubMed Central

    Semde, Gisèle; Sika, Lazare; Crucitti, Tania; Ettiegne Traore, Virginie; Buve, Anne; Laga, Marie

    2012-01-01

    Objectives To assess condom use and prevalence of sexually transmitted infections (STI) and HIV among male sex workers (MSW) in Abidjan, Côte d'Ivoire. Methods A cross-sectional survey was conducted between October 2007 and January 2008 among MSW attending a sex worker clinic in Abidjan. A short questionnaire was administered in a face-to-face interview, and the participants were asked to provide a urine sample for STI testing and to self-collect transudate of the gingival mucosa for anonymous HIV testing, using a rapid test. A rectal swab for STI testing was taken by a physician. Molecular amplification assays were performed for the detection of Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis. Results 96 MSW participated in the survey, their median age was 27?years and the median duration of sex work was 5?years. Consistent condom use with clients during the last working day was 86.0%, and consistent condom use with the regular partner during the last week was 81.6%. HIV infection was detected in 50.0% of the participants. The prevalence of N gonorrhoeae was 12.8%, chlamydia infection was present in 3.2% and T vaginalis in 2.1% of the study participants. Conclusions HIV and STI rates found in this study confirm the high risk and vulnerability status of MSW in Côte d'Ivoire. There is a definite need for studies exploring risk and risk perceptions among MSW in more depth and for services tailored to their needs, including developing and validating simple algorithms for the diagnosis of STI in MSW and men who have sex with men. PMID:22328644

  3. Anopheles arabiensis egg treatment with dieldrin for sex separation leaves residues in male adult mosquitoes that can bioaccumulate in goldfish (Carassius auratus auratus).

    PubMed

    Yamada, Hanano; Jandric, Zora; Chhem-Kieth, Sorivan; Vreysen, Marc J B; Rathor, Mohammad N; Gilles, Jeremie R L; Cannavan, Andrew

    2013-12-01

    The sterile insect technique (SIT) is a biological control tactic that is used as a component of area-wide integrated pest management (AW-IPM) programs. The SIT can only be applied against disease-transmitting mosquitoes when only sterile male mosquitoes are released, and the blood-sucking and potentially disease-transmitting females are eliminated from the production line. For Anopheles arabiensis, a potent vector of malaria, a genetic sexing strain was developed whereby females can be eliminated by treating the eggs or larvae with the insecticide dieldrin. To evaluate the presence of dieldrin residues in male mosquitoes designated for SIT releases, a simple, sensitive, and accurate gas chromatography-electron capture detector (GC-ECD) method was developed. In addition, bioaccumulation and food chain transfer of these residues to fish after feeding with treated mosquitoes was demonstrated. The overall recovery from method validation studies was 77.3?±?2.2% (mean?±?relative standard deviation [RSD]) for the mosquitoes, and 99.1?±?4.4% (mean?±?RSD) for the fish. The average dieldrin concentration found in adult male An. arabiensis was 28.1?±?2.9?µg/kg (mean?±?standard deviation [SD]). A range of 23.9?±?1.1?µg/kg to 73.9?±?5.2?µg/kg (mean?±?SD) of dieldrin was found in the fish samples. These findings indicate the need to reassess the environmental and health implications of control operations with a SIT component against An. arabiensis that involves using persistent organochlorines in the sexing process. PMID:23983078

  4. Combined Leydig cell and Sertoli cell dysfunction in 46,XX males lacking the sex determining region Y gene

    SciTech Connect

    Turner, B.; Vordermark, J.S. [Texas Tech Univ. Health Sciences Center, Lubbock, TX (United States); Fechner, P.Y. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States)] [and others

    1995-07-03

    We have evaluated 3 individuals with a rare form of 46,XX sex reversal. All of them had ambiguous external genitalia and mixed wolffian and muellerian structures, indicating both Leydig cell and Sertoli cell dysfunction, similar to that of patients with true hermaphroditism. However, gonadal tissue was not ovotesticular but testicular with varying degrees of dysgenesis. SRY sequences were absent in genomic DNA from peripheral leukocytes in all 3 subjects. Y centromere sequences were also absent, indicating that testis development did not occur because of a low level mosaicism of Y-bearing cells. The subjects in this report demonstrate that there is a continuum in the extent of the testis determination in SRY-negative 46,XX sex reversal, ranging from nearly normal to minimal testicular development. 20 refs.

  5. Caste and sex specific olfactory glomerular organization and brain architecture in two sympatric ant species Camponotus sericeus and Camponotus compressus

    E-print Network

    Caste and sex specific olfactory glomerular organization and brain architecture in two sympatric Accepted 8 June 2009 Keywords: Ants Antennal lobes Glomeruli Morphological castes a b s t r a c t We use the architecture of the antennal lobes in different castes of two ant species ­ Camponotus seri- ceus

  6. Effects of medroxyprogesterone acetate on subjective arousal, arousal to erotic stimulation, and nocturnal penile tumescence in male sex offenders

    Microsoft Academic Search

    John P. Wincze; Sudhir Bansal; Mark Malamud

    1986-01-01

    Three chronic pedophiliac sex offenders were treated individually with medroxyprogesterone acetate (MPA) over a minumum of 3 months. Genital and subjective response to erotic stimulation, nocturnal penile tumescence, self-reporting of sexual urges, and testosterone levels were recorded repeatedly throughout the study. A single-subject reversal design was used and medication was administered through a double-blind procedure. The results showed that self-report

  7. Antiperoxidative Activity of Tetracarpidium conophorum Leaf Extract in Reproductive Organs of Male Rats.

    PubMed

    Akomolafe, Seun Funmilola; Oboh, Ganiyu; Akindahunsi, Afolabi Akintunde; Afolayan, Anthony Jide

    2015-01-01

    Tetracarpidium conophorum (Mull. Arg.) Hutch. & Dalz is one of the many medicinal plants used in folklore as male fertility enhancers. This research was aimed at evaluating the anti-peroxidative activity of the leaves of this plant by determining their capacity to reduce malondialdehyde (MDA) level in reproductive organs and accessory glands of rats. Adult male rats were administered orally with the aqueous leaf extract from T. conophorum at 50, 500 and 1000?mg/kg body weight for 21 consecutive days while clomiphene citrate (1.04?mg/kg body weight), a fertility drug was used as standard. The results of the study indicated that there was increase in relative organ weight, body weight, mean total food and water consumed by the treated groups. Testicular MDA level was highly significantly different from that of the control (p < 0.0001) although a tentatively decreased MDA level was observed. However, MDA levels in the reproductive accessory glands, epididymis, seminal vesicle and prostate gland were insignificantly (p < 0.05) lower than those of controls. The highest percentage decrease of MDA level (66.35, 42.68, 62.50 and 63.36%) was observed at the highest concentration of the extract (1000?mg/kg) in the testis, epididymis, seminal vesicle and prostate gland respectively. These values were two-fold greater than the values obtained for the standard drug. Interestingly, the treatment of rats with the extract significantly increased the activities of superoxide dismutase, catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and the levels of GSH, vitamin C and total protein. Collectively, the results suggest that the extract from T. conophorum leaves had greater capacity to reduce lipid peroxidation in reproductive organs and accessory glands and thus, this plant may be useful in the treatment/management of reproductive cellular damage involving reactive oxygen species. PMID:26064173

  8. Antiperoxidative Activity of Tetracarpidium conophorum Leaf Extract in Reproductive Organs of Male Rats

    PubMed Central

    Akomolafe, Seun Funmilola; Akindahunsi, Afolabi Akintunde; Afolayan, Anthony Jide

    2015-01-01

    Tetracarpidium conophorum (Mull. Arg.) Hutch. & Dalz is one of the many medicinal plants used in folklore as male fertility enhancers. This research was aimed at evaluating the anti-peroxidative activity of the leaves of this plant by determining their capacity to reduce malondialdehyde (MDA) level in reproductive organs and accessory glands of rats. Adult male rats were administered orally with the aqueous leaf extract from T. conophorum at 50, 500 and 1000?mg/kg body weight for 21 consecutive days while clomiphene citrate (1.04?mg/kg body weight), a fertility drug was used as standard. The results of the study indicated that there was increase in relative organ weight, body weight, mean total food and water consumed by the treated groups. Testicular MDA level was highly significantly different from that of the control (p < 0.0001) although a tentatively decreased MDA level was observed. However, MDA levels in the reproductive accessory glands, epididymis, seminal vesicle and prostate gland were insignificantly (p < 0.05) lower than those of controls. The highest percentage decrease of MDA level (66.35, 42.68, 62.50 and 63.36%) was observed at the highest concentration of the extract (1000?mg/kg) in the testis, epididymis, seminal vesicle and prostate gland respectively. These values were two-fold greater than the values obtained for the standard drug. Interestingly, the treatment of rats with the extract significantly increased the activities of superoxide dismutase, catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and the levels of GSH, vitamin C and total protein. Collectively, the results suggest that the extract from T. conophorum leaves had greater capacity to reduce lipid peroxidation in reproductive organs and accessory glands and thus, this plant may be useful in the treatment/management of reproductive cellular damage involving reactive oxygen species.

  9. Pubertal effects of 17?-methyltestosterone on GH-IGF-related genes of the hypothalamic-pituitary-liver-gonadal axis and other biological parameters in male, female and sex-reversed Nile tilapia.

    PubMed

    Phumyu, Nonglak; Boonanuntanasarn, Surintorn; Jangprai, Araya; Yoshizaki, Goro; Na-Nakorn, Uthairat

    2012-06-01

    The influence of 17?-methyltestosterone (MT) on growth responses, biological parameters and the expression of genes involved in the GH-IGF pathway of the hypothalamic-pituitary-liver-gonadal axis were investigated in female, male, and sex-reversed Nile tilapia to evaluate the relationship between sex and MT-induced changes in these parameters. Female fish had a lower growth rate than male and sex-reversed fish, and MT increased growth performance and duodenal villi in females. Most but not all biological parameters of sex-reversed fish were similar to those of male fish. Male fish had higher red blood cell counts and hemoglobin levels than female and sex-reversed fish, suggesting that these hematological indices reflect a higher metabolic rate in male fish. Greater blood triglyceride levels indicated the vitellogenin process in female fish. MT increased the alternative complement activity in female fish (P<0.05). Sex and MT had no significant effects on the hypothalamic mRNAs of GHRH and PACAP. Although not statistically significant, females tended to have higher GH mRNA levels than male and sex-reversed fish. Additionally, MT tended to decrease and increase GH mRNA levels in female and male fish, respectively. There were significant differences among sexes in the expression of GHR, and IGF mRNAs at the peripheral level in the liver and gonads. Females had lower hepatic GHRs and higher ovarian GHRs than male and sex-reversed fish. While the mRNA levels of IGF-1 were lower in the ovary, the levels of IGF-2 were higher compared with those in testes. A significant correlation between GHRs and IGFs was demonstrated in the liver and gonad (except for IGF-1). Multiple regression analysis showed a significant relationship between GH mRNA and both GHRs and IGFs in the liver and gonad. MT exerted androgenic and, to some extent, estrogenic effects on several physiological parameters and GH-IGF action. PMID:22481004

  10. Effects of age, sex, and persistent organic pollutants on DNA methylation in children.

    PubMed

    Huen, Karen; Yousefi, Paul; Bradman, Asa; Yan, Liying; Harley, Kim G; Kogut, Katherine; Eskenazi, Brenda; Holland, Nina

    2014-04-01

    Epigenetic changes such as DNA methylation may be a molecular mechanism through which environmental exposures affect health. Methylation of Alu and long interspersed nucleotide elements (LINE-1) is a well-established measure of DNA methylation often used in epidemiologic studies. Yet, few studies have examined the effects of host factors on LINE-1 and Alu methylation in children. We characterized the relationship of age, sex, and prenatal exposure to persistent organic pollutants (POPs), dichlorodiphenyl trichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs), with DNA methylation in a birth cohort of Mexican-American children participating in the CHAMACOS study. We measured Alu and LINE-1 methylation by pyrosequencing bisulfite-treated DNA isolated from whole blood samples collected from newborns and nine-year old children (n?=?358). POPs were measured in maternal serum during late pregnancy. Levels of DNA methylation were lower in nine-year olds compared to newborns and were higher in boys compared to girls. Higher prenatal DDT/E exposure was associated with lower Alu methylation at birth, particularly after adjusting for cell type composition (P?=?0.02 for o,p' -DDT). Associations of POPs with LINE-1 methylation were only identified after examining the co-exposure of DDT/E with PBDEs simultaneously. Our data suggest that repeat element methylation can be an informative marker of epigenetic differences by age and sex and that prenatal exposure to POPs may be linked to hypomethylation in fetal blood. Accounting for co-exposure to different types of chemicals and adjusting for blood cell types may increase sensitivity of epigenetic analyses for epidemiological studies. PMID:24375655

  11. Can Sex Offender Classification Inform Typologies of Male Batterers? A Response to Holtzworth-Munroe and Meehan

    ERIC Educational Resources Information Center

    Prentky, Robert A.

    2004-01-01

    Etiologic and taxonomic research on rapists during the past decade suggests three dimensions that may be potentially useful for classification research on male batterers: (a) distinction between those whose anger is exclusively misogynistic and those whose anger is pervasive or undifferentiated with respect to target, (b) attitudes characterized…

  12. Sex-linked Correlated Responses in Female Reproductive Traits to Selection on Male Eye Span in Stalk-eyed Flies.

    PubMed

    Wilkinson, Gerald S; Amitin, Emily G; Johns, Philip M

    2005-06-01

    Coevolution between male and female traits can result from correlated responses to selection or correlated selection on genetically independent traits. This study examines the possibility that traits involved in precopulatory sexual selection may influence the evolution of traits involved in postcopulatory sexual selection due to the existence of correlated selection or correlated responses to selection. Artificial selection on male eye span in Cyrtodiopsis dalmanni, a sexually dimorphic stalk-eyed fly, is used to test for correlated changes in reproductive traits of male and female flies. Flies from replicate lines that had been under selection for 57 generations were matched for age and genotyped at four X-linked microsatellite loci. Egg number and testis size increased with age, but did not differ among lines. Spermathecal areas and duct lengths differed among replicates, but not among selection treatments. Female relative eye span, size of the ventral receptacle and egg size exhibited significant correlated responses to selection on male relative eye span. The absence of any change in sperm length or testis size between lines indicates that changes in female traits are unlikely due to correlated selection mediated by sperm competition. Significant effects of X-linked microsatellite genotypes indicate instead that the correlated responses to selection were due, in part, to X-linked genes in linkage disequilibrium or that exhibit pleiotropy. The presence of nonadditive allelic effects on genetically correlated female traits combined with additive allelic effects on a male ornament provides a previously unrecognized mechanism by which genetic variation could be maintained despite strong sexual selection. PMID:21676795

  13. Spindle Self-organization and Cytokinesis During Male Meiosis in asterless Mutants of Drosophila melanogaster

    PubMed Central

    Bonaccorsi, Silvia; Giansanti, Maria Grazia; Gatti, Maurizio

    1998-01-01

    While Drosophila female meiosis is anastral, both meiotic divisions in Drosophila males exhibit prominent asters. We have identified a gene we call asterless (asl) that is required for aster formation during male meiosis. Ultrastructural analysis showed that asl mutants have morphologically normal centrioles. However, immunostaining with antibodies directed either to ? tubulin or centrosomin revealed that these proteins do not accumulate in the centrosomes, as occurs in wild-type. Thus, asl appears to specify a function required for the assembly of centrosomal material around the centrioles. Despite the absence of asters, meiotic cells of asl mutants manage to develop an anastral spindle. Microtubules grow from multiple sites around the chromosomes, and then focus into a peculiar bipolar spindle that mediates chromosome segregation, although in a highly irregular way. Surprisingly, asl spermatocytes eventually form a morphologically normal ana–telophase central spindle that has full ability to stimulate cytokinesis. These findings challenge the classical view on central spindle assembly, arguing for a self-organization of this structure from either preexisting or newly formed microtubules. In addition, these findings strongly suggest that the asters are not required for signaling cytokinesis. PMID:9700163

  14. Adult male emigration and a female-based social organization in swift foxes, Vulpes velox

    Microsoft Academic Search

    Jan F Kamler; Warren B Ballard; Eric M Gese; Robert L Harrison; Seija Karki; Kevin Mote

    2004-01-01

    Members of the family Canidae are distinguished from other carnivore families by pair bonding and male care of the young. Because of the importance of food provisioning and territorial defence by males, social structure among canids is shared or even dominated by males. However, small, insectivorous species of canids show little male parental care, although whether social structure differs from

  15. Sex differences in baroreflex sensitivity, heart rate variability, and end organ damage in the TGR(mRen2)27 rat

    PubMed Central

    Johnson, Megan S.; DeMarco, Vincent G.; Heesch, Cheryl M.; Whaley-Connell, Adam T.; Schneider, Rebecca I.; Rehmer, Nathan T.; Tilmon, Roger D.; Ferrario, Carlos M.

    2011-01-01

    The aim of this investigation was to evaluate sex differences in baroreflex and heart rate variability (HRV) dysfunction and indexes of end-organ damage in the TG(mRen2)27 (Ren2) rat, a model of renin overexpression and tissue renin-angiotensin-aldosterone system overactivation. Blood pressure (via telemetric monitoring), blood pressure variability [BPV; SD of systolic blood pressure (SBP)], spontaneous baroreflex sensitivity, HRV [HRV Triangular Index (HRV-TI), standard deviation of the average NN interval (SDNN), low and high frequency power (LF and HF, respectively), and Poincaré plot analysis (SD1, SD2)], and cardiovascular function (pressure-volume loop analysis and proteinuria) were evaluated in male and female 10-wk-old Ren2 and Sprague Dawley rats. The severity of hypertension was greater in Ren2 males (R2-M) than in Ren2 females (R2-F). Increased BPV, suppression of baroreflex gain, decreased HRV, and associated end-organ damage manifested as cardiac dysfunction, myocardial remodeling, elevated proteinuria, and tissue oxidative stress were more pronounced in R2-M compared with R2-F. During the dark cycle, HRV-TI and SDNN were negatively correlated with SBP within R2-M and positively correlated within R2-F; within R2-M, these indexes were also negatively correlated with end-organ damage [left ventricular hypertrophy (LVH)]. Furthermore, within R2-M only, LVH was strongly correlated with indexes of HRV representing predominantly vagal (HF, SD1), but not sympathetic (LF, SD2), variability. These data demonstrated relative protection in females from autonomic dysfunction and end-organ damage associated with elevated blood pressure in the Ren2 model of hypertension. PMID:21821781

  16. Venous thrombo-embolism as a complication of cross-sex hormone treatment of male-to-female transsexual subjects: a review.

    PubMed

    Asscheman, H; T'Sjoen, G; Lemaire, A; Mas, M; Meriggiola, M C; Mueller, A; Kuhn, A; Dhejne, C; Morel-Journel, N; Gooren, L J

    2014-09-01

    Administration of cross-sex hormones to male-to-female transsexual subjects, usually oestrogens + often anti-androgens, such as cyproterone acetate, carries a risk of venous thromboembolism (VTE). VTE usually occurs in the first year of oestrogen administration. Ethinyl oestradiol, due to its chemical structure, was in 2003 identified as a major factor in the occurrence of VTE. Most clinics do not prescribe ethinyl oestradiol any longer, but people who take hormones without medical supervision use often oral contraceptives containing ethinyl oestradiol, many times in overdose. Cessation of use of ethinyl oestradiol and peri-operative thrombosis prophylaxis for surgery have reduced prevalence rate of VTE. Other oral oestrogens should not be overdosed, and transdermal oestrogen is to be preferred. Thrombosis prophylaxis for surgery is mandatory. It seems advisable to stop hormone use at least 2 weeks before major surgery, to be resumed only after 3 weeks following full mobilisation. PMID:23944849

  17. Anxious Attachment, Social Isolation, and Indicators of Sex Drive and Compulsivity: Predictors of Child Sexual Abuse Perpetration in Adolescent Males?

    PubMed

    Miner, Michael H; Swinburne Romine, Rebecca; Robinson, Beatrice Bean E; Berg, Dianne; Knight, Raymond A

    2014-08-20

    It has been suggested that child sexual abuse is related to poor attachment to parents, which is associated with an inability to form intimate relationships. Seto and Lalumière indicated that there were too few studies of adolescent males to determine whether poor attachment was associated with perpetration. This study was designed to follow up on a previous study and further explored the association between insecure attachment to parents, social isolation, and interpersonal adequacy to child sexual abuse perpetration in adolescents. We compared two samples of adolescent males who had committed sexual offenses, those who committed offenses against children (n = 140) and those who committed offenses against peer or adults (n = 92), with a sample of similarly aged males in treatment for mental health or substance use issues (n = 93). Data were collected using a semi-structured interview and computer-administered questionnaire. We found an indirect association between anxious attachment and sexual offenses against child victims, which was accounted for by measures of social involvement and social isolation. These involvement and isolation measures also did not have a direct association with sexual offenses against child victims, in that their contribution was accounted for by a measure of Masculine Adequacy. This Masculine Adequacy, combined with decreased levels of Sexual Preoccupation and Hypersexuality and increased Sexual Compulsivity, was associated with commission of child sexual abuse. The interpersonal variables did not enter a model predicting sexual offending against peers/adults, which seemed solely associated with the interaction between Sexual Compulsivity and Hypersexuality. PMID:25143437

  18. Gonadal Steroid Modulation of Sleep and Wakefulness in Male and Female Rats Is Sexually Differentiated and Neonatally Organized by Steroid Exposure

    PubMed Central

    Hadjimarkou, Maria M.; Mong, Jessica A.

    2014-01-01

    The paucity of clinical and preclinical studies investigating sex differences in sleep has resulted in mixed findings as to the exact nature of these differences. Although gonadal steroids are known to modulate sleep in females, less is known about males. Moreover, little evidence exists concerning the origin of these sex differences in sleep behavior. Thus, the goal of this study was to directly compare the sensitivity of sleep behavior in male and female Sprague Dawley rats to changes in the gonadal steroid milieu and to test whether the sex differences in sleep are the result of brain sexual differentiation or differences in circulating gonadal steroids. Here we report the magnitude of change in sleep behavior induced by either estradiol (E2) or testosterone (T) was greater in females compared with males, suggesting that sleep behavior in females is more sensitive to the suppressive effects of gonadal steroids. Furthermore, we demonstrated that the organizational effects of early gonadal steroid exposure result in male-like responsivity to gonadal steroids and directly alter the activity of the ventrolateral preoptic area (VLPO), an established sleep-promoting nucleus, in adult masculinized females. Moreover, the nonaromatizable androgen dihydrotestosterone did not suppress sleep in either males or females, suggesting that the T-mediated effect in females was due to the aromatization of T into E2. Together our data suggest that, like sex behavior, sex differences in sleep follow the classical organizational/activational effects of gonadal steroids. PMID:24189140

  19. Male pattern baldness (image)

    MedlinePLUS

    Male pattern baldness is a sex-linked characteristic that is passed from mother to child. A man can more accurately predict his chances of developing male pattern baldness by observing his mother's father than by looking ...

  20. SRY Induced TCF21 Genome-Wide Targets and Cascade of bHLH Factors During Sertoli Cell Differentiation and Male Sex Determination in Rats1

    PubMed Central

    Bhandari, Ramji K.; Schinke, Ellyn N.; Haque, Md. M.; Sadler-Riggleman, Ingrid; Skinner, Michael K.

    2012-01-01

    ABSTRACT Male sex determination is initiated through the testis-determining factor SRY that promotes Sertoli cell differentiation and subsequent gonadal development. The basic helix-loop-helix (bHLH) gene Tcf21 was identified as one of the direct downstream targets of SRY. The current study was designed to identify the downstream targets of TCF21 and the potential cascade of bHLH genes that promote Sertoli cell differentiation. A modified ChIP-Chip comparative hybridization analysis identified 121 direct downstream binding targets for TCF21. The gene networks and cellular pathways potentially regulated by these TCF21 targets were identified. One of the main bHLH targets for TCF21 was the bHLH gene scleraxis (Scx). An embryonic ovarian gonadal cell culture was used to examine the functional role of Sry, Tcf21, and Scx to promote an in vitro sex reversal and induction of Sertoli cell differentiation. SRY and TCF21 were found to induce the initial stages of Sertoli cell differentiation, whereas SCX was found to induce the later stages of Sertoli cell differentiation associated with pubertal development using transferrin gene expression as a marker. Therefore, a cascade of SRY followed by TCF21 followed by SCX appears to promote, in part, Sertoli cell fate determination and subsequent differentiation. The current observations help elucidate the initial molecular events involved in the induction of Sertoli cell differentiation and testis development. PMID:23034159

  1. Sex: Making the Right Decision

    MedlinePLUS

    MENU Return to Web version Sex: Making the Right Decision Sex: Making the Right Decision What is sex? The word sex is used in several ways. It can refer ... by the penis. It also can mean what sex you were born (male or female) or physical ...

  2. Self-organization in the spatial battle of the sexes with probabilistic updating

    NASA Astrophysics Data System (ADS)

    Alonso-Sanz, Ramón

    2011-08-01

    The dynamics of a spatial formulation of the iterated battle of the sexes with probabilistic updating is assessed in this work. The game is played in the cellular automata manner, i.e., with local and synchronous interaction. The effect of memory of past encounters is also taken into account. It is concluded that the spatial structure enables the emergence of clusters of coincident choices, leading to the mean payoff per encounter to values that are accessible only in the cooperative two-person game scenario, which constitutes a notable case of self-organization. With probabilistic updating of choices, both kinds of players reach mean payoffs per encounter that are notably higher than those reached with a deterministic updating mechanism, albeit the evolutionary dynamics does not stabilize, and one of the two possible choices tends to prevail for both kinds of players. Memory of past iterations induces an inertial effect that moderates this tendency, so that intermediate levels of the memory charge tend to favor fairly stable high egalitarian payoffs, without impeding the necessary recovering from their initial plummeting.

  3. Predictions for sex of first born child reflect masculine and feminine characteristics in male and female undergraduates.

    PubMed

    Palmer-Hague, Jaime L; Zilioli, Samuele; Watson, Neil V

    2013-01-01

    Previous research has identified physical and behavioral differences between parents who produce sons and those who produce daughters. However, the possibility that men and women have predictions about the sexes of their offspring based on these differences, or any other interoceptive cues, has not been investigated. We compared the dominance, sociosexual orientation, estradiol, testosterone, and 2D:4D ratios of men and women who predicted they would conceive a boy as their first child with those who predicted a girl. Women who predicted they would have a boy were more dominant and less sociosexually restricted than those who predicted they would have a girl. Men who predicted they would have a girl had higher salivary estradiol and higher (more feminine) 2D:4D ratios than those who predicted they would have a boy. Possible implications of these results are discussed in the context of evolutionary theory. PMID:23942345

  4. Sex expression and sex dimorphism in sporophytic populations of the desert moss Syntrichia caninervis

    Microsoft Academic Search

    Lloyd Stark; Nicholas McLetchie; Brent Mishler

    2001-01-01

    Ten sporophytic populations of Syntrichiacaninervis contained an average of 22 individualscm-2, with a sex ratio of 7.9 Female:1 Male: 3.1 Nonexpressing(N = 300). In each of the populations, female individuals outnumberedmale individuals. A representative population size of 50 × 25cm was estimated to contain 27,250 organically distinct individualplants. Given the wide disparity in reproductive investment in this dioeciousspecies, sex-specific traits

  5. Detection of Simian Immunodeficiency Virus in Semen, Urethra, and Male Reproductive Organs during Efficient Highly Active Antiretroviral Therapy

    PubMed Central

    Matusali, G.; Dereuddre-Bosquet, N.; Le Tortorec, A.; Moreau, M.; Satie, A.-P.; Mahé, D.; Roumaud, P.; Bourry, O.; Sylla, N.; Bernard-Stoecklin, S.; Pruvost, A.; Le Grand, R.

    2015-01-01

    ABSTRACT A number of men receiving prolonged suppressive highly active antiretroviral therapy (HAART) still shed human immunodeficiency virus (HIV) in semen. To investigate whether this seminal shedding may be due to poor drug penetration and/or viral production by long-lived cells within male genital tissues, we analyzed semen and reproductive tissues from macaques chronically infected with simian immunodeficiency virus mac251 (SIVmac251) who were treated for 4 months with HAART, which was intensified over the last 7 weeks with an integrase inhibitor. We showed that a subset of treated animals continued shedding SIV in semen despite efficient HAART. This shedding was not associated with low antiretroviral drug concentrations in semen or in testis, epididymis, seminal vesicles, and prostate. HAART had no significant impact on SIV RNA in the urethra, whereas it drastically reduced SIV RNA levels in the prostate and vas deferens and to a lesser extent in the epididymis and seminal vesicle. The only detectable SIV RNA-positive cells within the male genital tract after HAART were urethral macrophages. SIV DNA levels in genital tissues were not decreased by HAART, suggesting the presence throughout the male genital tract of nonproductively infected cells. In conclusion, our results demonstrate that 4 months of HAART induced variable and limited control of viral infection in the male reproductive organs, particularly in the urethra, and suggest that infected long-lived cells in the male genital tract may be involved in persistent seminal shedding during HAART. These results pave the way for further investigations of male genital organ infection in long-term-treated infected individuals. IMPORTANCE A substantial subset of men receiving prolonged HAART suppressing viral loads in the blood still harbor HIV in semen, and cases of sexual transmission have been reported. To understand the origin of this persistence, we analyzed the semen and male reproductive tissues from SIV-infected macaques treated with HAART. We demonstrated that persistent seminal shedding was not linked to poor drug penetration in semen or semen-producing prostate, seminal vesicle, epididymis, and testis. We revealed that HAART decreased SIV RNA to various extents in all male genital organs, with the exception of the urethra, in which SIV RNA+ macrophages were observed despite HAART. Importantly, HAART did not impact SIV DNA levels in the male genital organs. These results suggest that infection of male genital organs, and particularly the urethra, could be involved in the release of virus in semen during HAART. PMID:25833047

  6. Localization of male-specifically expressed MROS genes of Silene latifolia by PCR on flow-sorted sex chromosomes and autosomes.

    PubMed Central

    Kejnovský, E; Vrána, J; Matsunaga, S; Soucek, P; Siroký, J; Dolezel, J; Vyskot, B

    2001-01-01

    The dioecious white campion Silene latifolia (syn. Melandrium album) has heteromorphic sex chromosomes, XX in females and XY in males, that are larger than the autosomes and enable their separation by flow sorting. The group of MROS genes, the first male-specifically expressed genes in dioecious plants, was recently identified in S. latifolia. To localize the MROS genes, we used the flow-sorted X chromosomes and autosomes as a template for PCR with internal primers. Our results indicate that the MROS3 gene is located in at least two copies tandemly arranged on the X chromosome with additional copy(ies) on the autosome(s), while MROS1, MROS2, and MROS4 are exclusively autosomal. The specificity of PCR products was checked by digestion with a restriction enzyme or reamplification using nested primers. Homology search of databases has shown the presence of five MROS3 homologues in A. thaliana, four of them arranged in two tandems, each consisting of two copies. We conclude that MROS3 is a low-copy gene family, connected with the proper pollen development, which is present not only in dioecious but also in other dicot plant species. PMID:11454773

  7. Field response of male pine sawflies, Neodiprion sertifer (Diprionidae), to sex pheromone analogs in Japan and Sweden.

    PubMed

    Anderbrant, Olle; Löfqvist, Jan; Hedenström, Erik; Bång, Joakim; Tai, Akira; Högberg, Hans-Erik

    2010-09-01

    The pine sawfly Neodiprion sertifer (Geoffroy) uses the acetate or propionate of (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) as pheromone components, with the (2S,3R,7R)-isomer being antagonistic, synergistic, or inactive according to the population tested. In this study, we tested the attraction of males to the acetates of three analogs of diprionol, each missing one methyl group, viz. (2S,7S)-7-methyl-2-pentadecanol, (2S,6S)-2,6-dimethyl-1-tetradecanol, and (2S,3S)-3-methyl-2-pentadecanol. None of the analogs alone, or in combination with diprionol acetate, was attractive in Sweden, even at 100 times the amount of diprionol acetate attractive to N. sertifer. In Japan, the acetate of (2S,3S)-3-methyl-2-pentadecanol attracted males when tested in amounts 10-20 times higher than the acetate pheromone component. The acetate esters of the (2S,3R)-analog and the (2S,3R,7R)-isomer of diprionol also were tested in combination with the pheromone compound (acetate ester). Both compounds caused an almost total trap-catch reduction in Sweden, whereas in Japan they appear to have relatively little effect on trap capture when added to diprionol acetate. Butyrate and iso-butyrate esters of diprionol were unattractive to N. sertifer in Sweden. In summary, there exists geographic variation in N. sertifer in responses to both diprionyl acetate and some of its analogs. PMID:20680415

  8. Males in Psychotherapy.

    ERIC Educational Resources Information Center

    Toomer, Jerry E.

    1978-01-01

    This article discusses the effects of the male sex role upon male behavior in psychotherapy, showing research results for both therapist and client behavior. The research suggested that male clients tended not to disclose as freely, and that male therapists were perceived as less expressive than females. (LPG)

  9. Population density influences male–male competition in guppies

    Microsoft Academic Search

    Mullica Jirotkul

    1999-01-01

    This study tested the general prediction that population density affects male–male competition, female mate choice and the opportunity for sexual selection. By manipulating the density of guppies, Poecilia reticulata, while keeping the sex ratio constant, I found that male mating tactics were phenotypically plastic with respect to density. As density increased, males decreased their courtship displays. Male–male competition and mate

  10. The Effects of Sex of Subject, Sex and Attractiveness of Photo on Facial Recognition.

    ERIC Educational Resources Information Center

    Carroo, Agatha W.; Mozingo, R.

    1989-01-01

    Assessed effect of sex of subject, and sex and attractiveness of photo on facial recognition with 25 male and 25 female college students. Found male subjects performed better with male faces with d' prime scores. (Author/ABL)

  11. Distribution of 24 elements in the internal organs of normal males and the metallic workers in Japan.

    PubMed

    Teraoka, H

    1981-01-01

    Concentrations of 24 elements in the internal organs from 12 healthy males and from 7 metallic workers in Japan were recorded. Markedly high concentrations of chromium were found in the respiratory organs (e.g., hilar lymph node and lung) of chromium plating and chromate refining workers, as well as in spleen, liver, kidney, and heart. High chromium concentrations were also found in one male who had terminated his employment 30 years prior to his death. In addition, high concentrations of nickel and tin were also found in the above-mentioned workers. Marked accumulations of titanium, the main element of paints, were found in the respiratory organs, spleen, liver, kidney, and heart of an airplane painter. The painter also had high concentrations of chromium, nickel, and cobalt in some of his organs. It was also noted that high concentrations of silicon, aluminum, and titanium-elements of rock-occurred in a stone mason. PMID:7271320

  12. Sex Differences in the Effects of Neighborhood Socioeconomic Disadvantage and Social Organization on Rural Adolescents’ Aggression Trajectories

    Microsoft Academic Search

    Katherine J. Karriker-Jaffe; Vangie A. Foshee; Susan T. Ennett; Chirayath Suchindran

    2009-01-01

    We determined whether effects of neighborhood socioeconomic disadvantage on trajectories of aggression were moderated or mediated\\u000a by neighborhood social organization and examined sex differences in neighborhood effects for rural adolescents. We used five\\u000a waves of survey data collected over 2.5 years linked with neighborhood data from interviews with parents and the US Census.\\u000a The sample (N = 5,118) was 50.1% female, 52.0% white

  13. MALE HOMOSEXUAL IDENTITIES, RELATIONSHIPS, AND PRACTICES AMONG YOUNG MEN WHO HAVE SEX WITH MEN IN VIETNAM: IMPLICATIONS FOR HIV PREVENTION

    PubMed Central

    Ngo, Duc Anh; Ross, Michael W.; Phan, Ha; Ratliff, Eric A.; Trinh, Thang; Sherburne, Lisa

    2010-01-01

    Rapid socioeconomic transformation in Vietnam in last 15 years has been followed by more liberation of sexual expression and representation of sexual identity among young people. There has been an increase in the visibility of homosexual men in major cities of Vietnam who were largely an unknown population until the emergence of the HIV epidemic. Men who have sex with men (MSM) are now considered as one of the target groups in many HIV prevention programs. This qualitative study examines local identities, relationships, and sexual practices among young MSM aged 15–24 in the cities of Hanoi and Ho Chi Minh City. Our analyses were based on 26 in-depth interviews and 10 focus group discussions with young MSM recruited through public place intercepts and cruising areas. Data document the linguistic classification, sexual relationships and behaviors, identity and process of homosexual identification, and the potential linkage between sexual identity and sexual behaviors of MSM in Vietnam. Data also highlight the stages of homosexual community development in urban Vietnam and important differences between Vietnam and the West in the representation of homosexual identity, relationships, and practices. In light of the findings, we suggest that the continuing development and elaboration of a homosexual community in Hanoi and Ho Chi Minh City offers significant opportunities for targeted HIV/AIDS prevention activities in the Vietnamese MSM population. PMID:19519239

  14. Chemical and Physical Cues Synergistically Affect Mating Behavior Sequences of Male Dasylepida ishigakiensis (Coleoptera: Scarabaeidae).

    PubMed

    Fujiwara-Tsujii, Nao; Yasui, Hiroe; Arakaki, Norio

    2014-09-01

    We investigated physical and chemical cues involved in male mating behavior of the white grub beetle, Dasylepida ishigakiensis (Scarabaeidae). When presented with female attractant pheromone (R)-2-butanol lures in a flight tunnel, nearly all males exhibited orientation and touching behaviors to freshly killed males and females and to intact glass models. Males landed and bent their abdomens on male and female bodies, but not on intact glass models. When treated with one female equivalent (FE) extract, washed immature male bodies and glass models both evoked stronger male responses than untreated equivalents, with the former eliciting a greater response than the treated glass models. Male responses to target male and female bodies decreased with increased numbers of washings of target bodies with organic solvents. These results suggest that the chemical factors that elicit male abdominal bending behavior are present on the body surface in both sexes. Washed immature male bodies treated with 1 FE or one male equivalent (ME) of extract induced strong male abdominal bending behavior. Washed mature female bodies treated with 1 ME extract also evoked male responses. Extracts of both sexes included factors eliciting male abdominal bending behavior. These results suggest that both physical and chemical cues derived from conspecifics cooperate to facilitate male mating recognition in D. ishigakiensis. The mating process of this species in the field is highly synchronized. Thus, after orienting to a female-like object, the only information males require by touching is whether the sex attractant pheromone that attracted them is indeed from a conspecific. PMID:25186925

  15. Inhibition of steroid receptor coactivator-1 blocks estrogen and androgen action on male sex behavior and associated brain plasticity.

    PubMed

    Charlier, Thierry D; Ball, Gregory F; Balthazart, Jacques

    2005-01-26

    Studies of eukaryotic gene expression demonstrate the importance of nuclear steroid receptor coactivators in mediating efficient gene transcription. However, little is known about the physiological role of these coactivators in vivo. In Japanese quail, the steroid receptor coactivator-1 (SRC-1) is broadly expressed in steroid-sensitive brain areas that control the expression of male copulatory behavior, and we investigated the role of this coactivator by antisense technology. Daily intracerebroventricular injections of locked nucleic acid (LNA) antisense (AS) oligonucleotides targeting SRC-1 significantly reduced the expression of androgen- and estrogen-dependent male-typical sexual behaviors compared with control animals that received the vehicle alone or scrambled oligonucleotides. Sexual behavior was restored and even enhanced within 48 h after interruption of LNA injections. Western blot analysis confirmed the decrease of SRC-1 expression in AS animals and suggested an overexpression 48 h after the end of injections. The effects of SRC-1 knock-down on behavior correlated with a reduction in volume of the preoptic medial nucleus (POM) when its borders were defined by Nissl staining or by aromatase immunohistochemistry. The amount of aromatase-immunoreactive material in POM was also reduced in the AS compared with the control group. Previous work on SRC-1 knock-out mice raised questions about the importance of this specific coactivator in the regulation of reproductive behavior and development of sexually dimorphic structures in the CNS. Together, the present findings indicate that SRC-1 modulates steroid-dependent gene transcription and behavior and highlight the rapid time course of steroid-induced brain plasticity in adult quail. PMID:15673671

  16. Mutations in exons of the CYP17-II gene affect sex steroid concentration in male Japanese flounder ( Paralichthys olivaceus)

    NASA Astrophysics Data System (ADS)

    Ma, Ruiqin; He, Feng; Wen, Haishen; Li, Jifang; Shi, Bao; Shi, Dan; Liu, Miao; Mu, Weijie; Zhang, Yuanqing; Hu, Jian; Han, Weiguo; Zhang, Jianan; Wang, Qingqing; Yuan, Yuren; Liu, Qun

    2012-03-01

    As a specific gene of fish, cytochrome P450c17-II ( CYP17-II) gene plays a key role in the growth, development an reproduction level of fish. In this study, the single-stranded conformational polymorphism (SSCP) technique was used to characterize polymorphisms within the coding region of CYP17-II gene in a population of 75 male Japanese flounder ( Paralichthys olivaceus). Three single nucleotide polymorphisms (SNPs) were identified in CYP17-II gene of Japanese flounder. They were c.G594A (p.G188R), c.G939A and c.G1502A (p.G490D). SNP1 (c.G594A), located in exon 4 of CYP17-II gene, was significantly associated with gonadosomatic index (GSI). Individuals with genotype GG of SNP1 had significantly lower GSI ( P < 0.05) than those with genotype AA or AG. SNP2 (c.G939A) located at the CpG island of CYP17-II gene. The mutation changed the methylation of exon 6. Individuals with genotype AA of SNP2 had significantly lower serum testosterone (T) level and hepatosomatic index (HSI) compared to those with genotype GG. The results suggested that SNP2 could influence the reproductive endocrine of male Japanese flounder. However, the SNP3 (c.G1502A) located in exon 9 did not affect the four measured reproductive traits. This study showed that CYP17-II gene could be a potentially useful candidate gene for the research of genetic breeding and physiological aspects of Japanese flounder.

  17. A cross-sectional study of HIV and syphilis infections among male students who have sex with men (MSM) in northeast China: implications for implementing HIV screening and intervention programs

    Microsoft Academic Search

    Jun-Jie Xu; Kathleen Heather Reilly; Chun-Ming Lu; Ning Ma; Min Zhang; Zhen-Xing Chu; Jun-Jie Wang; Ke Yun; Hong Shang

    2011-01-01

    Background  China has 76.2 million high school and college students, in which the number of reported HIV\\/AIDS cases is increasing rapidly.\\u000a Most of these cases are attributed to male-to-male sexual contact. Few studies have explored HIV prevalence and behavioural\\u000a characteristics of Chinese male students who have sex with men (MSM).\\u000a \\u000a \\u000a \\u000a \\u000a Methods  A cross-sectional study of MSM high school and college students in

  18. Sex hormones, immune responses, and autoimmune diseases. Mechanisms of sex hormone action.

    PubMed Central

    Ansar Ahmed, S.; Penhale, W. J.; Talal, N.

    1985-01-01

    Immune reactivity is greater in females than in males. In both experimental animals and in man there is a greater preponderance of autoimmune diseases in females, compared with males. Studies in many experimental models have established that the underlying basis for this sex-related susceptibility is the marked effects of sex hormones. Sex hormones influence the onset and severity of immune-mediated pathologic conditions by modulating lymphocytes at all stages of life, prenatal, prepubertal, and postpubertal. However, despite extensive studies, the mechanisms of sex hormone action are not precisely understood. Earlier evidence suggested that the sex hormones acted via the thymus gland. In recent years it has become apparent that sex hormones can also influence the immune system by acting on several nonclassic target sites such as the immune system itself (nonthymic lymphoid organs), the central nervous system, the macrophage-macrocyte system, and the skeletal system. Immunoregulatory T cells appear to be most sensitive to sex hormone action among lymphoid cells. Several mechanisms of action of sex hormones are discussed in this review. The possibility of using sex hormone modulation of immune responses for the treatment of autoimmune disorders is a promising area for future investigation. Images Figure 1 PMID:3907369

  19. [Effects of captopril on the male reproductive organs and various semen parameters of rabbits].

    PubMed

    Köhler-Samouilidis, G; Schmidt-Adamopoulou, B; Samouilidis, S; Papaioannou, N; Kotsaki-Kovatsi, V P

    1997-06-01

    The effect of the administration of captopril on the concentrations of Zn, Cu, Mg and Ca into different organs, on their histological structure and several semen parameters of male rabbits was studied. For 9 weeks 6.5 mgs captopril/kg b.w. were administered daily to 7 months old White New Zealand rabbits p.o. Semen samples were collected at the beginning of the experiment and after 4 and 9 weeks. The animals were sacrificed 9 weeks after the beginning of the experiment and organ samples were collected for histological examination and for the determination of the Zn, Cu, Mg and Ca concentrations in several tissues and the semen samples. The absolute and relative weight of the right and left testes of the test animals revealed a tendency for increase. Absolute and relative weight of the right epididymis and the relative weight of the left epididymis were significantly increased. The concentration of Zn in the blood, of Cu and Ca in the epididymis and of Mg in the testes of the test animals were significantly decreased. A significant increase was observed of the Cu and Mg concentrations in the adrenals. In the semen Cu concentration was significantly increased 9 weeks after the beginning of the experiment. Mg concentration was significantly decreased 9 weeks as compared with 4 weeks after the beginning of the experiment. Histological examination of tissue specimens of brain, liver, kidney, adrenal glands, testes, epididymis, ductus deferens and seminal vesicles from all experimental animals didn't reveal any remarkable lesion under the light microscope. The other semen parameters like volume, motility, sperm number and morphology had not changed. As the values of alcalic and acid phosphatase and ASAT in the semen samples showed many variations, statistical analysis could not be performed. PMID:9290042

  20. Sex and breed-dependent organ development and metabolic responses in foetuses from lean and obese/leptin resistant swine.

    PubMed

    Torres-Rovira, Laura; Tarrade, Anne; Astiz, Susana; Mourier, Eve; Perez-Solana, Mariluz; de la Cruz, Paloma; Gomez-Fidalgo, Ernesto; Sanchez-Sanchez, Raul; Chavatte-Palmer, Pascale; Gonzalez-Bulnes, Antonio

    2013-01-01

    The present study aimed to determine the effects of breed and sex on growth patterns and metabolic features of advanced-pregnancy foetuses exposed to the same environmental conditions. Thus, at Day 62 of pregnancy, swine foetuses from an obese breed with leptin resistance (Iberian breed) were compared to lean crossbred foetuses (25% Large White ×25% Landrace ×50% Pietrain). There were differential developmental patterns in foetuses with leptin resistance, mainly a higher relative weight of the brain resembling "brain-sparing effect". Prioritization of brain growth may be protective for the adequate growth and postnatal survival of the Iberian individuals, an ancient breed reared in extensive semi-feral conditions for centuries. There were also clear sex-related differences in foetal development and metabolism in the Iberian breed. Female Iberian foetuses were similar in size and weight to male littermates but had a significantly higher relative liver to body weight ratio resembling "liver-sparing effect" and a trend for a higher relative intestine to body ratio. Moreover, the availability of triglycerides, cholesterol and IL-6 in female Iberian foetuses was similar to that of lean crossbred foetuses. Overall, these features may favour a better postnatal survival and development of females, the sex more critical for the species survival. These findings set the basis for future translational studies aimed at increasing the knowledge on the interaction between genetic and environmental factors in the early programming of the adult phenotype. PMID:23935823

  1. [Effect of estradiol valerate on the male reproductive organs and various semen parameters in rats].

    PubMed

    Köhler-Samouilidis, G; Papaioannou, N; Kotsaki-Kovatsi, V P; Vadarakis, A

    1998-01-01

    The effect of the administration of estradiol valerate on the male reproductive organs, on their histological structure, and several semen parameters of Wistar rats was studied. In experiment A and B 140 micrograms estradiol valerate/kg b.w. were administered once a week for 4 weeks to 14 weeks old rats by s.c. injection. One week after the 4th injection the rats of experiment A were sacrificed, while the rats of experiment B lived 5 weeks without treatment for recovery. In both experiments, suppression of body weight, food consumption, decreases in absolute and relative weights of testes, epididymides, prostate and semen vesicles were observed along with testis, epididymis, seminal vesicle and prostate atrophy. The absolute and relative weights of adrenals and pituitary revealed a tendency for increase in both treated groups. The histopathological examination of the testes revealed degeneration of spermatozytes in experiment A, and degeneration of spermatozytes, spermatides, spermatozoa, Sertoli and Leydig cells in experiment B. In experiment A the motility, and number of sperms was significantly decreased, the sperm abnormalities were significantly increased. In experiment B the motility of sperms was slightly, the number significantly decreased and the abnormalities slightly increased. PMID:9499618

  2. Constraints on the coevolution of contemporary human males and females

    PubMed Central

    Stearns, Stephen C.; Govindaraju, Diddahally R.; Ewbank, Douglas; Byars, Sean G.

    2012-01-01

    Because autosomal genes in sexually reproducing organisms spend on average half their time in each sex, and because the traits that they influence encounter different selection pressures in males and females, the evolutionary responses of one sex are constrained by processes occurring in the other sex. Although intralocus sexual conflict can restrict sexes from reaching their phenotypic optima, no direct evidence currently supports its operation in humans. Here, we show that the pattern of multivariate selection acting on human height, weight, blood pressure and glucose, total cholesterol, and age at first birth differs significantly between males and females, and that the angles between male and female linear (77.8 ± 20.5°) and nonlinear (99.1 ± 25.9°) selection gradients were closer to orthogonal than zero, confirming the presence of sexually antagonistic selection. We also found evidence for intralocus sexual conflict demonstrated by significant changes in the predicted male and female responses to selection of individual traits when cross-sex genetic covariances were included and a significant reduction in the angle between male- and female-predicted responses when cross-sex covariances were included (16.9 ± 15.7°), compared with when they were excluded (87.9 ± 31.6°). We conclude that intralocus sexual conflict constrains the joint evolutionary responses of the two sexes in a contemporary human population. PMID:23034705

  3. “You Can’t Do Nothing in This Damn Place”: Sex and Intimacy Among Couples With an Incarcerated Male Partner

    PubMed Central

    Comfort, Megan; Grinstead, Olga; McCartney, Kathleen; Bourgois, Philippe; Knight, Kelly

    2009-01-01

    In an effort to deepen our understanding of how circumstances of forced separation and the interdiction of physical contact affect women’s sexual behavior, we investigated the development and maintenance of heterosexual couples’ intimacy when the male partner is incarcerated. As HIV-prevention scientists who work with women visiting men at a California state prison, we recognize that correctional control extends to these women’s bodies, both when they are within the facility’s walls visiting their mates and when they are at home striving to remain connected to absent men. This paper analyzes the impact of a peculiar public “place”—a penitentiary— on couples’ romantic and sexual interactions, drawing out the implications of imprisonment for relationship decision making, sexual health, and HIV risk. Using qualitative interviews with 20 women who visit their incarcerated partners and 13 correctional officers who interact with prison visitors, we examine how institutional constraints such as the regulation of women’s apparel, the prohibition of physical contact, and the lack of privacy result in couples forging alternative “spaces” in which their relationships occur. We describe how romantic scripts, the build-up of sexual tension during the incarceration period, and conditions of parole promote unprotected sexual intercourse and other HIV/STD risk behavior following release from prison. PMID:15795799

  4. Comparison of non-invasive methods for the assessment of haemodynamic drug effects in healthy male and female volunteers: sex differences in cardiovascular responsiveness.

    PubMed Central

    Wolzt, M; Schmetterer, L; Rheinberger, A; Salomon, A; Unfried, C; Breiteneder, H; Ehringer, H; Eichler, H G; Fercher, A F

    1995-01-01

    1. The study was performed to determine the sensitivity and short-term and day-to-day variability of a novel technique based on laser interferometry of ocular fundus pulsations and of non-invasive methods for the quantification of haemodynamic drug effects. An additional aim was to assess sex differences in haemodynamic responsiveness to cardiovascular drugs in male and female healthy volunteers. 2. Ten males and nine females (age range 20-33 years) were studied in a double-blind, randomized, cross-over trial. Simultaneous measurements from systemic haemodynamics, laser interferometry of ocular fundus pulsations, systolic time intervals from mechanocardiography, a/b ratio from oxymetric fingerplethysmography and Doppler sonography of the radial artery were used to describe the haemodynamic effects of cumulative, stepwise increasing intravenous doses of phenylephrine, isoprenaline, sodium nitroprusside and of placebo. 3. Laser interferometry detected the isoprenaline-effects at the lowest dose level of 0.1 micrograms min-1 with a high signal-to-noise ratio. The reproducibility of measurements under baseline was high, no changes were observed after systemically effective doses of phenylephrine or sodium nitroprusside. Systolic time intervals were sensitive and specific for isoprenaline-induced effects, PEP and QS2c-measurements had high reproducibility. Fingerplethysmography proved a sensitive measurement for the detection of the vasodilating effects of sodium nitroprusside, but was not specific, and showed low reproducibility. Measurements from Doppler sonography had lower reproducibility and sensitivity compared with the other applied methods. 4. There was a significant sex difference for several of the haemodynamic parameters under baseline conditions; however, the responsiveness to the drugs under study was not different, when drug effects were expressed as %-change from the baseline. 5. Laser interferometry is a valuable non-invasive, highly sensitive and specific approach for the detection of pulse pressure changes. A battery of non-invasive tests appears useful for the characterization of cardiovascular drugs. Gender differences may not pose a relevant problem for the study of acute haemodynamic effects of cardiovascular drugs. Images Figure 1 PMID:7640140

  5. The effects of age and sex on seven elements in Sprague-Dawley rat organs

    Microsoft Academic Search

    Eiji Uchino; Toshibumi Tsuzuki; Katsuhiro Inoue

    1990-01-01

    Summary This study reports age-related changes in 7 element (iron, copper, zinc, manganese, mercury, cadmium and lead) concentrations in the liver, kid- ney and brain of male and female Sprague-Dawley rats from 1 to 364 days of age. Atomic absorp- tion spectrometry was used for the measurements. Copper, mercury and cadmium in the male and female kidneys increased from weaning

  6. Comparison of organ dose and dose equivalent using ray tracing of male and female Voxel phantoms to space flight phantom torso data

    Microsoft Academic Search

    Myung-Hee Kim; Garry Qualls; Tony Slaba; Francis A. Cucinotta

    2008-01-01

    Phantom torso experiments have been flown on the space shuttle and International Space Station (ISS) providing validation data for radiation transport models of organ dose and dose equivalents. We describe results for space radiation organ doses using a new human geometry model based on detailed Voxel phantoms models denoted for males and females as MAX (Male Adult voXel) and Fax

  7. Social Support, Exposure to Violence and Transphobia, and Correlates of Depression Among Male-to-Female Transgender Women With a History of Sex Work

    PubMed Central

    Bödeker, Birte; Iwamoto, Mariko

    2011-01-01

    Objectives. We determined racial/ethnic differences in social support and exposure to violence and transphobia, and explored correlates of depression among male-to-female transgender women with a history of sex work (THSW). Methods. A total of 573 THSW who worked or resided in San Francisco or Oakland, California, were recruited through street outreach and referrals and completed individual interviews using a structured questionnaire. Results. More than half of Latina and White participants were depressed on the basis of Center For Epidemiologic Studies Depression Scale scores. About three quarters of White participants reported ever having suicidal ideation, of whom 64% reported suicide attempts. Half of the participants reported being physically assaulted, and 38% reported being raped or sexually assaulted before age 18 years. White and African American participants reported transphobia experiences more frequently than did others. Social support, transphobia, suicidal ideation, and levels of income and education were significantly and independently correlated with depression. Conclusions. For THSW, psychological vulnerability must be addressed in counseling, support groups, and health promotion programs specifically tailored to race/ethnicity. PMID:21493940

  8. Repeated in utero and lactational 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure affects male gonads in offspring, leading to sex ratio changes in F{sub 2} progeny

    SciTech Connect

    Ikeda, Masahiko [University of Shizuoka, Graduate School of Nutritional and Environmental Sciences, 52-1, Yada, Shizuoka, 422 8526 (Japan) and CREST, Japan Science and Technology Corporation, Kawaguchi, 332-0012 (Japan)]. E-mail: ikedam@ys2.u-shizuoka-ken.ac.jp; Tamura, Masashi [University of Shizuoka, Graduate School of Nutritional and Environmental Sciences, 52-1, Yada, Shizuoka, 422 8526 (Japan); Yamashita, Junko [University of Shizuoka, Graduate School of Nutritional and Environmental Sciences, 52-1, Yada, Shizuoka, 422 8526 (Japan); Suzuki, Chinatsu [University of Shizuoka, Graduate School of Nutritional and Environmental Sciences, 52-1, Yada, Shizuoka, 422 8526 (Japan); Tomita, Takako [University of Shizuoka, Graduate School of Nutritional and Environmental Sciences, 52-1, Yada, Shizuoka, 422 8526 (Japan); CREST, Japan Science and Technology Corporation, Kawaguchi, 332-0012 (Japan)

    2005-08-15

    The effects of in utero and lactational 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the reproductive system of male rat offspring (F{sub 1}) and the sex ratio of the subsequent generation (F{sub 2}) were examined. Female Holtzman rats were gavaged with an initial loading dose of 400 ng/kg TCDD prior to mating, followed by weekly maintenance doses of 80 ng/kg during mating, pregnancy, and the lactation period. Maternal exposure to TCDD had no significant effects on fetus/pup (F{sub 1}) mortality, litter size, or sex ratio on gestation day (GD) 20 or postnatal day (PND) 2. The TCDD concentration in maternal livers and adipose tissue on GD20 was 1.21 and 1.81 ng/kg, respectively, and decreased at weaning to 0.72 in the liver and 0.84 in the adipose tissue. In contrast, the TCDD concentration in pup livers was 1.32 ng/kg on PND2 and increased to 1.80 ng/kg at weaning. Ventral prostate weight of male offspring was significantly decreased by TCDD exposure on PND28 and 120 compared with that of controls. Weight of the testes, cauda epididymides, and seminal vesicle, and sperm number in the cauda epididymis were not changed by TCDD exposure at PND120. TCDD- or vehicle-exposed male offspring were mated with unexposed females. The sex ratio (percentage of male pups) of F{sub 2} offspring was significantly reduced in the TCDD-exposed group compared with controls. These results suggest that in utero and lactational TCDD exposures affect the development of male gonads in offspring (F{sub 1}), leading to changes in the sex ratio of the subsequent generation (F{sub 2})

  9. Bizarre parasite that kills male insects and disrupts insect sex lives is not all bad: it can make sterile fruit flies fertile again

    NSDL National Science Digital Library

    Robert Sanders

    Researchers at UC Berkely discover that the bacterium Wolbachia pipientis allows a sterile female fruit fly to lay eggs, circumventing a genetic mutation in a gene that is the key to determining the sex of offspring, reports this campus news article. The article introduces the sex-lethal gene, Sxl, and offers a discussion of sex determination in Drosophila.

  10. Tricks of the Trade: Sexual Health Behaviors, the Context of HIV Risk, and Potential Prevention Intervention Strategies for Male Sex Workers

    Microsoft Academic Search

    Sari L. Reisner; Matthew J. Mimiaga; Kenneth H. Mayer; Jake P. Tinsley; Steven A. Safren

    2009-01-01

    Sex work is a significant risk for HIV and sexually transmitted infection (STI) among men who have sex with men (MSM); however, there is a dearth of knowledge about how to reduce risk in this group. MSM sex workers (N = 32) completed a semistructured qualitative interview and a close-ended quantitative assessment. Analyses focused on themes relevant to intervention development.

  11. POLLINATION INTENSITY INFLUENCES SEX RATIOS IN DIOECIOUS RUMEX NIVALIS, A WIND-POLLINATED PLANT

    Microsoft Academic Search

    Ivana Stehlik; Spencer C. H. Barrett

    2006-01-01

    Determining the mechanisms governing sex-ratio variation in dioecious organisms represents a central problem in evolutionary biology. It has been proposed that in plants with sex chromosomes competition between pollen tubes of female- versus male-determining microgametophytes (certation) causes female-biased primary sex ratios. Experimental support for this hypothesis is limited and recent workers have cast doubt on whether pollen-tube competition can modify

  12. Relative contribution of organs other than brain to resting energy expenditure is consistent among male power athletes.

    PubMed

    Oshima, Satomi; Miyauchi, Sakiho; Asaka, Meiko; Kawano, Hiroshi; Taguchi, Motoko; Torii, Suguru; Higuchi, Mitsuru

    2013-01-01

    We have previously shown that resting energy expenditure (REE) adjusted by fat-free mass (FFM) in male college athletes remains consistent regardless of FFM. The FFM comprises internal organs with high metabolic activity, such as liver and brain, which account for 60 to 80% of REE in adults. The purpose of the present study is to examine the contribution of internal organs to the REE of the FFM fraction among male power athletes. The study included 37 American male college football players. REE was measured by indirect calorimetry and body composition was measured by dual energy X-ray absorptiometry (DXA). Mass of brain, liver, and kidneys was measured by MRI and mass of heart was estimated by echocardiography. Normal levels of thyroid hormone (triiodothyronine: T3) were confirmed in all subjects prior to the analysis. Multiple regression analysis was used to assess the influence of FFM, fat mass (FM), T3, and mass of organs on variance of REE. Average body weight and FFM were 81.2±11.3 kg and 67.7±7.4 kg, respectively. The relative contributions of liver, kidneys, and heart to REE were consistent regardless of FFM, while the REE of brain was negatively correlated with FFM (r=-0.672, p<0.001). Only FFM and T3 were found to be independent factors influencing REE. These results suggest that a steady contribution of internal organs other than the brain is the major reason for the consistency of the REE/FFM ratio in male power athletes. PMID:23883693

  13. Expression of the rhesus glycoproteins, ammonia transporter family members, RHCG and RHBG in male reproductive organs

    PubMed Central

    Lee, Hyun-Wook; Verlander, Jill W; Handlogten, Mary E; Han, Ki-Hwan; Cooke, Paul S; Weiner, I David

    2015-01-01

    The rhesus glycoproteins, Rh B glycoprotein (RHBG) and Rh C glycoprotein (RHCG), are recently identified ammonia transporters. Rhcg expression is necessary for normal male fertility, but its specific cellular expression is unknown, and Rhbg has not been reported to be expressed in the male reproductive tract. This study sought to determine the specific cellular expression of Rhcg, to determine whether Rhbg is expressed in the male reproductive tract, and, if so, to determine which cells express Rhbg using real-time RT-PCR, immunoblot analysis, and immunohistochemistry. Both Rhbg and Rhcg were expressed throughout the male reproductive tract. In the testis, high levels of Rhbg were expressed in Leydig cells, and Rhcg was expressed in spermatids during the later stages of their maturation (steps 13–16) in stages I–VIII of the seminiferous epithelium cycle. In the epididymis, basolateral Rhbg was present in narrow cells in the initial segment, in principal cells in the upper corpus, and in clear cells throughout the epididymis. Apical Rhcg immunolabel was present in principal cells in the caput and upper corpus epididymidis and in clear cells in the middle and lower corpus and cauda epididymidis. In the vas deferens, apical Rhcg immunolabel and basolateral Rhbg immunolabel were present in some principal cells and colocalized with H+-ATPase immunolabel. We conclude that both Rhbg and Rhcg are highly expressed in specific cells in the male reproductive tract where they can contribute to multiple components of male fertility. PMID:23904565

  14. Expression of the rhesus glycoproteins, ammonia transporter family members, RHCG and RHBG in male reproductive organs.

    PubMed

    Lee, Hyun-Wook; Verlander, Jill W; Handlogten, Mary E; Han, Ki-Hwan; Cooke, Paul S; Weiner, I David

    2013-09-01

    The rhesus glycoproteins, Rh B glycoprotein (RHBG) and Rh C glycoprotein (RHCG), are recently identified ammonia transporters. Rhcg expression is necessary for normal male fertility, but its specific cellular expression is unknown, and Rhbg has not been reported to be expressed in the male reproductive tract. This study sought to determine the specific cellular expression of Rhcg, to determine whether Rhbg is expressed in the male reproductive tract, and, if so, to determine which cells express Rhbg using real-time RT-PCR, immunoblot analysis, and immunohistochemistry. Both Rhbg and Rhcg were expressed throughout the male reproductive tract. In the testis, high levels of Rhbg were expressed in Leydig cells, and Rhcg was expressed in spermatids during the later stages of their maturation (steps 13-16) in stages I-VIII of the seminiferous epithelium cycle. In the epididymis, basolateral Rhbg was present in narrow cells in the initial segment, in principal cells in the upper corpus, and in clear cells throughout the epididymis. Apical Rhcg immunolabel was present in principal cells in the caput and upper corpus epididymidis and in clear cells in the middle and lower corpus and cauda epididymidis. In the vas deferens, apical Rhcg immunolabel and basolateral Rhbg immunolabel were present in some principal cells and colocalized with H(+)-ATPase immunolabel. We conclude that both Rhbg and Rhcg are highly expressed in specific cells in the male reproductive tract where they can contribute to multiple components of male fertility. PMID:23904565

  15. Abnormal human sex chromosome constitutions

    SciTech Connect

    NONE

    1993-12-31

    Chapter 22, discusses abnormal human sex chromosome constitution. Aneuploidy of X chromosomes with a female phenotype, sex chromosome aneuploidy with a male phenotype, and various abnormalities in X chromosome behavior are described. 31 refs., 2 figs.

  16. Testosterone-induced phenotypic sex reversal in sheep 

    E-print Network

    Stiles, Maxine Lorene

    1979-01-01

    knowledge on sex differentiation has been contributed by Alfred Jost. Jost (1947) surgically castrated rabbit fetuses in utero and proved that female differentiation will occur in the absence of testes regardless of genotypic sex. In order to prevent... establishment of the Wolffian ducts, castration has to occur before day 24. Jost found that the target organs pass through a short critical stage when the testic- ular hormones will irreversibly direct organogenesis along male lines. In the female offspring...

  17. Sex Pheromone Traps for Monitoring the Peach Twig Borer, Anarsia lineatella Zeller: Effect of Pheromone Components, Pheromone Dose, Field Aging of Dispenser, and Type of Trap on Male Captures

    Microsoft Academic Search

    M. Kehat; L. Anshelevich; E. Dunkelblum; S. Greenberg

    1994-01-01

    The effects of ratio between sex pheromone components, pheromone dose in the dispenser, aging of dispenser in the field, and\\u000a trap type on trapping efficiency of males of the peach twig borer,Anarsia lineatella Zeller (Lepidoptera: Gelechiidae), were investigated. To attract males, the optimal ratio between pheromonal components in\\u000a a binary blend containing (E)-5-decenyl acetate (E5-10:Ac): (E)-5-decenol (E5-10:OH) was 72:28 or

  18. Male–Male Dimensions of Male–Female Battering: A New Look at Domestic Violence

    Microsoft Academic Search

    Jerry L. Jennings; Christopher M. Murphy

    2000-01-01

    The field of domestic violence has concentrated its theories, research, and treatment methods on the male–female dimensions of the problem. However, male–male issues also play a crucial role. The authors explain how traditional male socialization and rigid sex role stereotyping can have emotional and behavioral consequences that are displaced onto male–female relationships. In particular, \\

  19. Rhetorical Interactions of Social Movement Organizations in a Movement: A Study of the Intersex Rights Advocacy Movement

    E-print Network

    Topp, Sarah Suzanne

    2010-05-17

    down the treatment. He was confused by the lack of transparency and contradictory information from doctors. He felt like a male, but was labeled female and had no idea what his diagnosis actually was. Unfortunately, his story, as well as Chase... differentiation and how the development of intersexed bodies might differ from that. It is generally considered useful to view human sex as being contingent upon five separate aspects: genotypic sex (genes), gonadal sex (internal sex organs), hormonal sex...

  20. Implications of PEPFAR's anti-prostitution pledge for HIV prevention among organizations working with sex workers.

    PubMed

    Ditmore, Melissa; Allman, Dan

    2010-10-01

    Even though the United States President's Emergency Plan for AIDS Relief (PEPFAR) has facilitated access to treatment for people living with HIV/AIDS across the planet, sex workers are not as fortunate. In this article, based on an oral abstract presentation at AIDS 2010, Melissa Ditmore and Dan Allman present a case-story analysis of the implementation of PEPFAR's anti-prostitution pledge. PMID:21413636

  1. Male sex and vascular risk factors affect cystatin C-derived renal function in older people without diabetes or overt vascular disease

    PubMed Central

    Werner, Karin Birgitta; Elmståhl, Sölve; Christensson, Anders; Pihlsgård, Mats

    2014-01-01

    Background/objectives: to explore the effect of ageing on renal function with cystatin C as the marker of glomerular filtration rate (GFR) in the general population without vascular disease or diabetes. Design: a cross-sectional analysis of a healthy subset from the Good Aging in Skåne-cohort study representative of the Swedish general population. Subjects: 1252 participants without vascular disease and diabetes (43.9% men) of whom 203 were over 80 years old were included from the original cohort of 2931. Methods: plasma cystatin C and plasma creatinine were used as markers for GFR. Estimated GFR (eGFR) was calculated with three chronic kidney disease epidemiology collaboration (CKD-EPI) formulas involving cystatin C, creatinine or both. Results: the median for plasma cystatin C was 0.93 mg/l (60–69 years old), 1.04 (70–79 years old) and 1.24 (80+ years old). The difference in mg/l between the 5th and 95th percentile was 0.46, 0.62 and 0.90 for these age groups. Male sex increased the age effect on plasma cystatin C levels with 0.004 mg/l/year (P = 0.03), adjusted for vascular risk factors. Smoking, lower HDL and higher diastolic blood pressure were associated with higher cystatin C levels. 54.7% (CKD-EPI creatinine) to 73.9% (CKD-EPI cystatin C) of the 80+ had an eGFR < 60 ml/min/1.73 m2. Conclusion: non-diabetics without overt vascular disease exhibit an age related but heterogeneous decline in renal function. The ageing effect is more pronounced in men. At least half of healthy 80+ years old could be expected to have at least CKD Stage 3 with eGFR < 60 ml/min/1.73 m2. PMID:24321840

  2. Effect of chronic oestrogen administration on androgen receptor expression in reproductive organs and pituitary of adult male rat.

    PubMed

    Kaushik, M C; Misro, M M; Sehgal, N; Nandan, D

    2010-06-01

    Following chronic (15 or 30 days) treatment with oestradiol 3-benzoate (75 microg rat(-1) day(-1) in 100 microl of olive oil) to adult rats, androgen receptor (AR) expression was analysed simultaneously in testis, epididymis, seminal vesicle, prostate and pituitary utilising three independent tools i.e. immunohistochemistry, Western blotting and RT-PCR. All the five organs showed higher AR transcriptional activity gradually increasing from 15 to 30 days of oestrogen treatment. However, the AR protein expression either through immunostaining or Western blotting demonstrated a significant decline in all the reproductive organs. In the pituitary, on the other hand, the decline coincided with a distinct breakdown of the AR protein into two bands with increasing duration of treatment. Serum and intra-testicular testosterone levels were found significantly lowered. Spermatogenesis was adversely affected with concurrent decrease in weights of testis and accessory sex organs. Decrease in testis weight was consistent with the reduction in the number of maturing germ cells per tubule. Despite the decrease in weight, accessory sex organs like epididymis, seminal vesicle and prostate were completely devoid of any apoptotic cells which were characterised only in testis and pituitary. Seminiferous epithelium demonstrated a marked increase in the number of germ cells undergoing apoptosis. However, the rate of cell apoptosis was much higher in the pituitary than in the testis at the end of 30 days treatment. It is therefore concluded that degradation of AR protein expression after oestrogen treatment is probably directly linked to an increase in cell apoptosis both in testis and pituitary. PMID:20500749

  3. Organ dose conversion coefficients on an ICRP-based Chinese adult male voxel model from idealized external photons exposures

    NASA Astrophysics Data System (ADS)

    Liu, Liye; Zeng, Zhi; Li, Junli; Qiu, Rui; Zhang, Binquan; Ma, Jizeng; Li, Ren; Li, Wenqian; Bi, Lei

    2009-11-01

    A high-resolution whole-body voxel model called CAM representing the Chinese adult male was constructed in this paper based on a previous individual voxel model. There are more than 80 tissues and organs in CAM, including almost all organs required in the ICRP new recommendation. The mass of individual organs has been adjusted to the Chinese reference data. Special considerations were given to representing the gross spatial distribution of various bone constituents as realistically as possible during the construction of the site-specific skeleton. Organ dose conversion coefficients were calculated for six idealized external photon exposures from 10 keV to 10 MeV by using Monte Carlo simulation. The resulting dose coefficients were then compared with those from other models, e.g. CMP, ICRP 74, Rex, HDRK-man and VIP-man. Old and new effective male doses of CAM were calculated by using the tissue weighting factors from ICRP 60 and 103 Publications, respectively. Dosimetric differences between mathematical and voxel models, and the differences between Asian and Caucasian models are also discussed in this paper.

  4. Inclusion of the female condom in a male condom-only intervention in the sex industry in China: a cross-sectional analysis of pre- and post-intervention surveys in three study sites

    PubMed Central

    Liao, S.; Weeks, M.R.; Wang, Y.; Li, N.; Li, F.; Zhou, Y.; Zeng, X.; Jiang, J.; He, B.; Li, J.; Dunn, J.; Zhang, Q.

    2011-01-01

    SUMMARY Objectives To describe female condom (FC) use, male condom (MC) use and overall levels of protected sex before, during and after FC education and promotion (using the original prototype FC) combined with MC promotion among female sex workers in three rural or small urban settings in southern China. Study design The 1-year FC intervention was conducted by local health workers through outreach to establishments where sex work is conducted. Three serial cross-sectional surveys were conducted in each study town before, during and after the intervention along with process documentation throughout the intervention period. Methods Cross-sectional data from pre-intervention (baseline) and 6-month and 12-month post-intervention surveys from three study sites are used in a descriptive comparison of the context of the sex industry, outreach in two phases of intervention, and FC adoption after the intensive intervention phase in each site. Results Approximately 75–80% of eligible women working in sex establishments, varying from 74 to 155 participants for each survey, were recruited from three study sites. After introduction and promotion of the FC along with the MC during the community public health intervention, between one-fifth and one-half of the study participants had tried the FC in the three study sites by the time of the 6-month and 12-month cross-sectional surveys. Among them, 10–30% had used the FC more than once. FC awareness increased following the intervention with much less variation across the three study sites. At baseline, 31–54% of participants across the three sites reported 100% protected sex in the last 30 days with all types of partners. At one of the sites with relatively low MC use before the intervention, the proportion of women reporting 100% protected sex in the last 30 days increased by 15%, and the proportion reporting nil protected sex in the last 30 days decreased by 13% between baseline and 12-month post-intervention surveys. More complex profiles of FC and MC use and protected sex were shown at the other two study sites, where a higher level of protection had been reached before the project started. Conclusions Different levels of FC adoption were identified after the 1-year FC promotion intervention through outreach to sex establishments. The input, output and outcomes of the intervention may be associated with women’s demographic and risk characteristics, the local capacities of intervention staff, and other contextual factors. Further analysis of these factors will help establish the role of the FC in increasing protected sex, and provide insight into how to achieve greater FC use. PMID:21513961

  5. Does size dimorphism reduce competition between sexes? The diet of male and female pine martens at local and wider geographical scales

    Microsoft Academic Search

    Andrzej Zalewski

    2007-01-01

    Sex-specific niche segregation is often used to explain sexual size dimorphism (SSD). However, whether food niche partitioning\\u000a between sexes occurs as a case of sexual size dimorphism or by other mechanisms, such as behavioural dimorphism or habitat\\u000a segregation, remains poorly understood. To evaluate the nature and extent of food-niche differentiation between sexes in a\\u000a solitary predator I examined variation in

  6. Organization of actin cytoskeleton during meiosis I in a wheat thermo-sensitive genic male sterile line.

    PubMed

    Xu, Chenguang; Liu, Zetao; Zhang, Liping; Zhao, Changping; Yuan, Shaohua; Zhang, Fengting

    2013-02-01

    BS366 is a thermo-sensitive male sterile line of wheat (Triticum aestivum L.) for two-line hybrid breeding, which exhibits aberrant meiotic cytokinesis under low temperature. Through transcriptome analysis, a possible regulatory role for plant actin cytoskeleton was suggested. However, the organization of actin cytoskeleton in meiosis has been poorly understood so far. Here, fixed microsporocytes during meiosis were labeled with tetramethylrhodamine isothiocyanate-phalloidin and 4',6-diamidino-2-phenylindole. Quantities of fluorescent micrographs were captured using a confocal microscope, including the transient state from metaphase to telophase. We observed that actin filaments were abundant in typical kariokinetic spindle, central spindle (parallel microtubules or actin fibers between two separated chromosomes in anaphase), and phragmoplast. Interestingly, we identified the Chinese lantern-shaped actin phragmoplast in wheat meiosis for the first time. Under low temperature, phragmoplast actin filaments were chaotic and normal cell plate failed to form. These data provide new insights into the organization of actin filaments during male meiosis of plant and support a role of actin cytoskeleton in bringing about thermo-sensitive male sterility in wheat. PMID:22350736

  7. Same-sex pair-bonds are equivalent to male–female bonds in a life-long socially monogamous songbird

    Microsoft Academic Search

    Julie E. Elie; Nicolas Mathevon; Clémentine Vignal

    Same-sex sexual behaviors are well documented in both captive and wild animals. In monogamous species, these behaviors are\\u000a often exclusive, each individual having only one same-sex partner. A bias in sex ratio has been proposed as a social context\\u000a yielding same-sex pair-bonding, but this hypothesis has rarely been tested. Focusing on a life-long pair-bonding songbird,\\u000a the zebra finch Taeniopygia guttata,

  8. AbstractReproductive organs from 393 male and 382 female porbeagles

    E-print Network

    in the western North Atlantic Ocean, were examined to determine size at maturity and reproductive cycle. Males. The reproductive biology of the porbeagle shark (Lamna nasus) in the western North Atlantic Ocean Christopher F, 1984). In the western North (NW) Atlantic Ocean, the porbeagle ranges from the Flemish Cap

  9. Stress promotes maleness in hermaphroditic modular animals

    PubMed Central

    Hughes, R. N.; Manríquez, P. H.; Bishop, J. D. D.; Burrows, M. T.

    2003-01-01

    Sex-allocation theory developed for hermaphroditic plants predicts that impaired phenotype or reduced parental survivorship caused by environmental stress should induce relatively greater allocation to the male function. We provide experimental evidence of stress-induced maleness, already well documented in flowering plants, in a modular animal. By using cloned copies of replicate genotypes, we show that the marine bryozoan Celleporella hyalina increases the ratio of male to female modules in response to diverse environmental stressors. Mating trials confirmed that paternity is determined by fair-raffle sperm competition, which should obviate local mate competition at characteristic population density and promote the advantage of increased male allocation. The demonstrated similarity to plants transcends specific physiological pathways and suggests that stress-induced bias toward male function is a general response of hermaphroditic modular organisms to impaired prospects for parental productivity or survival. PMID:12930903

  10. Prevention of toxic effects of mercuric chloride on Some male accessory organs in mice with a Multiherbal drug “Speman”

    PubMed Central

    Rathore, H.S.

    2000-01-01

    Adult Swiss albino male mice exposed to mercuric chloride via drinking water at 5 ?g/ml for 100 days revealed significant reduction in the wet weight and severe histopathological changes in male accessory organs, poor level of serum testosterone and infertility. These effects were reduced remarkable and fertility was restored when drug (12.50 mg/mouse/day orally) was administered during mercury exposure for 100days or after Hg-exposure for next 60 days (Post therapy). Natural recovery after mercury exposure for 60 days remind ineffective. Probable action of herbal drug based on the presence of the active principles of constituents (i.e Orchis mascula, Mucuna pruriens, parmelia perlata, Argyreia speciosa, Tribulus terristris, Leptadenia reticulate, Lactuca scariola and Hygrophila spinosa) is discussed in detail. PMID:22556990

  11. Males of the two-spotted spider mite attempt to copulate with mated females: effects of double mating on fitness of either sex.

    PubMed

    Oku, Keiko

    2010-02-01

    In Tetranychus urticae (Acari: Tetranychidae), when the intervals between first and second copulation are more than 24 h, only the first copulation is effective for females. Therefore, adult males should copulate only with virgin females, but not with females that copulated more than 1 day ago. Indeed, T. urticae males preferred virgin females to mated females under dual choice conditions. In the absence of virgin females, however, 60% of males copulated with mated females (n = 30). Therefore, the effects of male copulation behaviour on male and mated-female fitness were examined, respectively. Since T. urticae is arrhenotokous (i.e., only daughters have genes derived from their father), the proportion of females among the offspring was used as an index of male fitness. After males had lived with/without a mated female, the males were allowed to copulate with a virgin female. The proportion of females among the offspring did not differ between males with and without a female. On the other hand, when mated females lived with an adult male, their egg production was lower than mated females without a male. These results suggest that males do not seem to obtain fitness benefit from the copulation behaviour and that mated females incur a fitness cost due to the male behaviour. PMID:19760507

  12. Seasonal and sex differences in the hippocampus of a wild rodent.

    PubMed

    Burger, Danielle K; Saucier, Jodi M; Iwaniuk, Andrew N; Saucier, Deborah M

    2013-01-01

    Studies across and within species suggest that hippocampus size is sexually dimorphic in polygamous species, but not in monogamous species. Although hippocampal volume varies with sex, season and mating system, few studies have simultaneously tested for sex and seasonal differences. Here, we test for sex and seasonal differences in the hippocampal volume of wild Richardson's ground squirrels (Urocitellus richardsonii), a polygamous species that lives in matrilineal, kin-based social groups and has profound sex differences in behavior. Based on the behavior and ecology of this species, we predicted that males would have a significantly larger hippocampus than females and that the hippocampus would be largest in males during the breeding season. Analyses of both absolute and relative volumes of the hippocampus yielded a significant difference between the sexes and seasons as well as an interaction between the two such that non-breeding males have significantly larger hippocampal volumes than breeding males or females from either season. Dentate gyrus, CA1 and CA3 subfield volumes were generally larger in the non-breeding season and in males, but no significant interaction effects were detected. This sex and seasonal variation in hippocampal volume is likely the result of their social organization and male-only food caching behavior during the non-breeding season. The demonstration of a sex and seasonal variation in hippocampal volume suggests that Richardson's ground squirrel may be a useful model for understanding hippocampal plasticity within a natural context. PMID:22974551

  13. Sex Difference in the Size of the Neural Song Control Regions in a Dueting Songbird with Similar Song Repertoire Size of Males and Females

    Microsoft Academic Search

    Manfred Gahr; Edith Sonnenschein; Wolfgang Wickler

    1998-01-01

    Previous studies have suggested a causal relation between sex differences in behavior such as singing and sex differences in the size of brain areas such as the forebrain song control areas of songbirds. In the present study we show that the size of the forebrain vocal control areas nucleus hyperstriatalis ventrale pars caudale (HVC) and nucleus robustus archistriatalis (RA) and

  14. Male-specific lethal 2, a dosage compensation gene of Drosophila, undergoes sex-specific regulation and encodes a protein with a RING finger and a metallothionein-like cysteine cluster.

    PubMed Central

    Zhou, S; Yang, Y; Scott, M J; Pannuti, A; Fehr, K C; Eisen, A; Koonin, E V; Fouts, D L; Wrightsman, R; Manning, J E

    1995-01-01

    In Drosophila the equalization of X-linked gene products between males and females, i.e. dosage compensation, is the result of a 2-fold hypertranscription of most of these genes in males. At least four regulatory genes are required for this process. Three of these genes, maleless (mle), male-specific lethal 1 (msl-1) and male-specific lethal 3 (msl-3), have been cloned and their products have been shown to interact and to bind to numerous sites on the X chromosome of males, but not of females. Although binding to the X chromosome is negatively correlated with the function of the master regulatory gene Sex lethal (Sxl), the mechanisms that restrict this binding to males and to the X chromosome are not yet understood. We have cloned the last of the known autosomal genes involved in dosage compensation, male-specific lethal 2 (msl-2), and characterized its product. The encoded protein (MSL-2) consists of 769 amino acid residues and has a RING finger (C3HC4 zinc finger) and a metallothionein-like domain with eight conserved and two non-conserved cysteines. In addition, it contains a positively and a negatively charged amino acid residue cluster and a coiled coil domain that may be involved in protein-protein interactions. Males produce a msl-2 transcript that is shorter than in females, due to differential splicing of an intron of 132 bases in the untranslated leader. Using an antiserum against MSL-2 we have shown that the protein is expressed at a detectable level only in males, where it is physically associated with the X chromosome. Our observations suggest that MSL-2 may be the target of the master regulatory gene Sxl and provide the basic elements of a working hypothesis on the function of MSL-2 in mediating the 2-fold increase in transcription that is characteristic of dosage compensation. Images PMID:7796814

  15. Reduction in ovulation or male sex phenotype increases long-term anoxia survival in a daf-16-independent manner in Caenorhabditis elegans

    PubMed Central

    Mendenhall, Alexander R.; LeBlanc, Michelle G.; Mohan, Desh P.; Padilla, Pamela A.

    2009-01-01

    Identifying genotypes and phenotypes that enhance an organism's ability to survive stress is of interest. We used Caenorhabditis elegans mutants, RNA interference (RNAi), and the chemical 5-fluorodeoxyuridine (FUDR) to test the hypothesis that a reduction in progeny would increase oxygen deprivation (anoxia) survival. In the hermaphrodite gonad, germ line processes such as spermatogenesis and oogenesis can be simultaneously as well as independently disrupted by genetic mutations. We analyzed genetic mutants [glp-1(q158), glp-4(bn2ts), plc-1(rx1), ksr-1(ku68), fog-2(q71), fem-3(q20), spe-9(hc52ts), fer-15(hc15ts)] with reduced progeny production due to various reproductive defects. Furthermore, we used RNAi to inhibit the function of gene products in the RTK/Ras/MAPK signaling pathway, which is known to be involved in a variety of developmental processes including gonad function. We determined that reduced progeny production or complete sterility enhanced anoxia survival except in the case of sterile hermaphrodites [spe-9(hc52ts), fer-15(hc15ts)] undergoing oocyte maturation and ovulation as exhibited by the presence of laid unfertilized oocytes. Furthermore, the fog-2(q71) long-term anoxia survival phenotype was suppressed when oocyte maturation and ovulation were induced by mating with males that have functional or nonfunctional sperm. The mutants with a reduced progeny production survive long-term anoxia in a daf-16- and hif-1-independent manner. Finally, we determined that wild-type males were able to survive long-term anoxia in a daf-16-independent manner. Together, these results suggest that the insulin signaling pathway is not the only mechanism to survive oxygen deprivation and that altering gonad function, in particular oocyte maturation and ovulation, leads to a physiological state conducive for oxygen deprivation survival. PMID:19050081

  16. Mitochondrial genome organization of the maize cytoplasmic male sterile type T

    Microsoft Academic Search

    Christiane Fauron; Marie Havlik; David Lonsdale; Lindy Nichols

    1989-01-01

    A complete SmaI, XhoI, BamHI restriction map of the maize mitochondrial genome from the T male sterile cytoplasm (cmsT) of maize has been established. The genome exists in the form of a complex multicircular structure as found for the maize normal (N) type (Lonsdale et al. 1984) where the entire sequence complexity with a content of 540 kb can be

  17. Three-dimensional antennal lobe atlas of the oriental fruit moth, Cydia molesta (Busck) (Lepidoptera: Tortricidae): comparison of male and female glomerular organization.

    PubMed

    Varela, Nélia; Couton, Louise; Gemeno, César; Avilla, Jesús; Rospars, Jean-Pierre; Anton, Sylvia

    2009-09-01

    The oriental fruit moth Cydia molesta is an important pest and the behavioural role of olfactory signals such as pheromones and plant volatiles have been studied extensively in both sexes. To understand odour processing further, however, detailed knowledge of the anatomy of the olfactory system is crucial. In the present study, an atlas of the antennal lobe (AL) is presented based on the three-dimensional reconstructions of both ALs of three male and three female brains by means of neuroanatomical and computational approaches. We identified 48-49 "ordinary" glomeruli and one large glomerulus situated at the entrance of the antennal nerve in males, and 49-52 "ordinary" glomeruli and one large glomerulus in the ventro-medial part of the AL in females. Anomalous supernumerary, anomalous missing and sexually dimorphic glomeruli were found in the studied individuals in greater numbers than in other lepidopteran species. Male and female maps were compared with respect to glomerular size and position with 45 glomeruli being matched, indicating a conserved glomerular pattern between the sexes. Three additional glomeruli were sexually dimorphic in size and five male-specific and six female-specific glomeruli were also found. Palp backfills resulted in the staining of a unique glomerulus in both sexes identified as the sexually dimorphic glomerulus 45. This glomerulus was never stained from antennal backfills, which stained the other glomeruli of the AL. The three-dimensional atlas can now be used to elucidate the functional role of individual glomeruli in both sexes of C. molesta. PMID:19649654

  18. Sexing young snowy owls

    USGS Publications Warehouse

    Seidensticker, M.T.; Holt, D.W.; Detienne, J.; Talbot, S.; Gray, K.

    2011-01-01

    We predicted sex of 140 Snowy Owl (Bubo scandiacus) nestlings out of 34 nests at our Barrow, Alaska, study area to develop a technique for sexing these owls in the field. We primarily sexed young, flightless owls (3844 d old) by quantifying plumage markings on the remiges and tail, predicting sex, and collecting blood samples to test our field predictions using molecular sexing techniques. We categorized and quantified three different plumage markings: two types of bars (defined as markings that touch the rachis) and spots (defined as markings that do not touch the rachis). We predicted sex in the field assuming that males had more spots than bars and females more bars than spots on the remiges and rectrices. Molecular data indicated that we correctly sexed 100% of the nestlings. We modeled the data using random forests and classification trees. Both models indicated that the number and type of markings on the secondary feathers were the most important in classifying nestling sex. The statistical models verified our initial qualitative prediction that males have more spots than bars and females more bars than spots on flight feathers P6P10 for both wings and tail feathers T1 and T2. This study provides researchers with an easily replicable and highly accurate method for sexing young Snowy Owls in the field, which should aid further studies of sex-ratios and sex-related variation in behavior and growth of this circumpolar owl species. ?? 2011 The Raptor Research Foundation, Inc.

  19. Evaluation of PCR-based beef sexing methods.

    PubMed

    Zeleny, Reinhard; Bernreuther, Alexander; Schimmel, Heinz; Pauwels, Jean

    2002-07-17

    Analysis of the sex of beef meat by fast and reliable molecular methods is an important measure to ensure correct allocation of export refunds, which are considerably higher for male beef meat. Two PCR-based beef sexing methods have been optimized and evaluated. The amelogenin-type method revealed excellent accuracy and robustness, whereas the bovine satellite/Y-chromosome duplex PCR procedure showed more ambiguous results. In addition, an interlaboratory comparison was organized to evaluate currently applied PCR-based sexing methods in European customs laboratories. From a total of 375 samples sent out, only 1 false result was reported (female identified as male). However, differences in the performances of the applied methods became apparent. The collected data contribute to specify technical requirements for a common European beef sexing methodology based on PCR. PMID:12105941

  20. The species, sex, and stage specificity of a Caenorhabditis sex pheromone

    E-print Network

    Chasnov, Jeffrey R.

    The species, sex, and stage specificity of a Caenorhabditis sex pheromone J. R. Chasnov*, W. K. So chemotaxis assays, we demonstrate that females secrete a potent sex pheromone that attracts males from a distance, whereas hermaphrodites do not. The female sex pheromone is not species-specific, with males

  1. Rethinking University Sex Education

    Microsoft Academic Search

    Margaret Brooks

    2011-01-01

    In recent years, some universities have allowed student organizations to hire sex workers, pornography producers and performers, and sex toy sales representatives to provide sex education on their campuses. Yet these individuals are not medical professionals, and the sexual health information they provide to students, if any, can sometimes be wrong. In addition, students attending these workshops can face additional

  2. Genomic organization of repetitive DNAs and its implications for male karyotype and the neo-Y chromosome differentiation in Erythrinus erythrinus (Characiformes, Erythrinidae)

    PubMed Central

    Yano, Cassia Fernanda; Bertollo, Luiz Antonio Carlos; Molina, Wagner Franco; Liehr, Thomas; Cioffi, Marcelo de Bello

    2014-01-01

    Abstract Studies have demonstrated the effective participation of repetitive DNA sequences in the origin and differentiation of the sex chromosomes in some biological groups. In this study several microsatellites and retrotranposable sequences were cytogenetically mapped in the Erythrinus erythrinus (Bloch & Schneider, 1801) male genome (karyomorph C), focusing on the distribution of these sequences in the sex chromosomes and in the evolutionary processes related to their differentiation. Males of E. erythrinus – karyomorph C – present 2n = 51 chromosomes (7m + 2sm + 6st + 36a), including the X1X2Y sex chromosomes. The C-positive heterochromatin has a predominant localization on the centromeric region of most chromosome pairs, but also in some telomeric regions. The 5S rDNA sites are located in the centromeric region of 27 chromosomes, including 26 acrocentric ones and the metacentric Y chromosome. The retrotransposons Rex 1 and Rex 6 show a dispersed pattern in the karyotype, contrasting with the Rex 3 distribution which is clearly co-localized with all the 27 5S rDNA sites. The microsatellite sequences show a differential distribution, some of them restricted to telomeric and/or interstitial regions and others with a scattered distribution on the chromosomes. However, no preferential accumulation of these elements were observed in the neo-Y chromosome, in contrast to what usually occurs in simple sex chromosome systems. PMID:25147625

  3. Obstructive Pulmonary Function Impairment among Korean Male Workers Exposed to Organic Solvents, Iron Oxide Dust, and Welding Fumes

    PubMed Central

    RYU, Ji Young; LEE, Sang-Yoon; KIM, Dae Hwan

    2013-01-01

    We evaluated spirometric obstructive pulmonary function impairment among workers who were occupationally exposed to organic solvents, iron oxide dust, or welding fumes. Data were collected from records of periodic health examinations of workers. In total, 448 Korean male workers were enrolled and classified into three exposure groups: exposure to organic solvents, iron oxide dust, or welding fumes. Logistic regression analysis was performed to evaluate the association between occupational exposure and pulmonary function. Compared to exposure to organic solvents, exposure to iron oxide dust was significantly associated with obstructive pulmonary function impairment (odds ratio [OR], 9.61; 95% confidence interval [CI], 2.20–41.97). The group exposed to welding fumes did not show a significantly higher OR compare to those exposed to organic solvents (OR, 2.83; 95% CI, 0.74–10.8). These results suggest that exposure to iron oxide dust has a greater association with obstructive pulmonary function impairment than exposure to organic solvents or welding fumes. PMID:24131874

  4. Comparison of Organ Location, Morphology, and Rib Coverage of a Midsized Male in the Supine and Seated Positions

    PubMed Central

    Hayes, Ashley R.; Gayzik, F. Scott; Moreno, Daniel P.; Martin, R. Shayn; Stitzel, Joel D.

    2013-01-01

    The location and morphology of abdominal organs due to postural changes have implications in the prediction of trauma via computational models. The purpose of this study is to use data from a multimodality image set to devise a method for examining changes in organ location, morphology, and rib coverage from the supine to seated postures. Medical images of a male volunteer (78.6 ± 0.77?kg, 175?cm) in three modalities (Computed Tomography, Magnetic Resonance Imaging (MRI), and Upright MRI) were used. Through image segmentation and registration, an analysis between organs in each posture was conducted. For the organs analyzed (liver, spleen, and kidneys), location was found to vary between postures. Increases in rib coverage from the supine to seated posture were observed for the liver, with a 9.6% increase in a lateral projection and a 4.6% increase in a frontal projection. Rib coverage area was found to increase 11.7% for the spleen. Morphological changes in the organs were also observed. The liver expanded 7.8% cranially and compressed 3.4% and 5.2% in the anterior-posterior and medial-lateral directions, respectively. Similar trends were observed in the spleen and kidneys. These findings indicate that the posture of the subject has implications in computational human body model development. PMID:23606901

  5. Sex differences in the neural circuit that mediates female sexual receptivity

    PubMed Central

    Flanagan-Cato, Loretta M.

    2011-01-01

    Female sexual behavior in rodents, typified by the lordosis posture, is hormone-dependent and sex-specific. Ovarian hormones control this behavior via receptors in the hypothalamic ventromedial nucleus (VMH). This review considers the sex differences in the morphology, neurochemistry and neural circuitry of the VMH to gain insights into the mechanisms that control lordosis. The VMH is larger in males compared with females, due to more synaptic connections. Another sex difference is the responsiveness to estradiol, with males exhibiting muted, and in some cases reverse, effects compared with females. The lack of lordosis in males may be explained by differences in synaptic organization or estrogen responsiveness, or both, in the VMH. However, given that damage to other brain regions unmasks lordosis behavior in males, a male-typical VMH is unlikely the main factor that prevents lordosis. In females, key questions remain regarding the mechanisms whereby ovarian hormones modulate VMH function to promote lordosis. PMID:21338620

  6. Self-Disclosure: A Function of Sex or Sex Role?

    ERIC Educational Resources Information Center

    Lombardo, John P.; Lavine, Linda O.

    Sex role differences in self disclosure are more clearly defined than are gender differences. Students filled out a Bem Sex Role Inventory (BSRI) as part of an introductory course requirement. Males and females who scored as either androgynous or stereotyped were selected for four targets: mother, father, male best friend, female best friend. Some…

  7. The influence of having children on HIV-related risk behaviors of female sex workers and their intimate male partners in two Mexico-US border cities.

    PubMed

    Rolon, Maria Luisa; Syvertsen, Jennifer L; Robertson, Angela M; Rangel, M Gudelia; Martinez, Gustavo; Ulibarri, Monica D; Servin, Argentina; Strathdee, Steffanie A

    2013-06-01

    Among female sex workers who use drugs, the experience of having children and its effect on HIV risk behaviors remains underexplored. We draw from a study of 214 female sex workers and their intimate non-commercial partners in Tijuana and Ciudad Juárez, México (n = 428), approximately 30% of whom have children living with them. During qualitative interviews with 41 of these couples, having children emerged as an important topic. Children influenced partners' lives and HIV-related risk behaviors in positive and negative ways. Couples perceived that children strengthened their relationships. Concern for children's well-being motivated couples to contemplate healthier lifestyle changes. However, childrearing costs motivated sex work and structural constraints prevented couples from enacting lifestyle changes. Case studies illustrate these themes and highlight implications for couple- and family-based harm reduction interventions. Specifically, our results suggest a need for economic alternatives to sex work while working with families to develop risk reduction skills. PMID:23418131

  8. Persistent organic pollution in a high-Arctic top predator: sex-dependent thresholds in adult survival.

    PubMed

    Erikstad, Kjell Einar; Sandvik, Hanno; Reiertsen, Tone Kristin; Bustnes, Jan Ove; Strøm, Hallvard

    2013-10-22

    In long-lived species, any negative effect of pollution on adult survival may pose serious hazards to breeding populations. In this study, we measured concentrations of various organochlorines (OCs) (polychlorinated biphenyl and OC pesticides) in the blood of a large number of adult glaucous gulls (Larus hyperboreus) breeding on Bjørnøya (Bear Island) in the Norwegian Arctic, and modelled their local survival using capture-recapture analysis. Survival was negatively associated with concentrations of OCs in the blood. The effect of OCs was nonlinear and evident only among birds with the highest concentrations (the uppermost deciles of contamination). The threshold for depressed survival differed between the sexes, with females being more sensitive to contamination. For birds with lower OC concentration, survival was very high, i.e. at the upper range of survival rates reported from glaucous and other large gull species in other, presumably less contaminated populations. We propose two non-exclusive explanations. First, at some threshold of OC concentration, parents (especially males) may abandon reproduction to maximize their own survival. Second, high contamination of OC may eliminate the most sensitive individuals from the population (especially among females), inducing a strong selection towards high-quality and less sensitive phenotypes. PMID:23966640

  9. Persistent organic pollution in a high-Arctic top predator: sex-dependent thresholds in adult survival

    PubMed Central

    Erikstad, Kjell Einar; Sandvik, Hanno; Reiertsen, Tone Kristin; Bustnes, Jan Ove; Strøm, Hallvard

    2013-01-01

    In long-lived species, any negative effect of pollution on adult survival may pose serious hazards to breeding populations. In this study, we measured concentrations of various organochlorines (OCs) (polychlorinated biphenyl and OC pesticides) in the blood of a large number of adult glaucous gulls (Larus hyperboreus) breeding on Bjørnøya (Bear Island) in the Norwegian Arctic, and modelled their local survival using capture–recapture analysis. Survival was negatively associated with concentrations of OCs in the blood. The effect of OCs was nonlinear and evident only among birds with the highest concentrations (the uppermost deciles of contamination). The threshold for depressed survival differed between the sexes, with females being more sensitive to contamination. For birds with lower OC concentration, survival was very high, i.e. at the upper range of survival rates reported from glaucous and other large gull species in other, presumably less contaminated populations. We propose two non-exclusive explanations. First, at some threshold of OC concentration, parents (especially males) may abandon reproduction to maximize their own survival. Second, high contamination of OC may eliminate the most sensitive individuals from the population (especially among females), inducing a strong selection towards high-quality and less sensitive phenotypes. PMID:23966640

  10. Sexual dimorphism and the evolution of sex-biased gene expression in the brown alga ectocarpus.

    PubMed

    Lipinska, Agnieszka; Cormier, Alexandre; Luthringer, Rémy; Peters, Akira F; Corre, Erwan; Gachon, Claire M M; Cock, J Mark; Coelho, Susana M

    2015-06-01

    Males and females often have marked phenotypic differences, and the expression of these dissimilarities invariably involves sex differences in gene expression. Sex-biased gene expression has been well characterized in animal species, where a high proportion of the genome may be differentially regulated in males and females during development. Male-biased genes tend to evolve more rapidly than female-biased genes, implying differences in the strength of the selective forces acting on the two sexes. Analyses of sex-biased gene expression have focused on organisms that exhibit separate sexes during the diploid phase of the life cycle (diploid sexual systems), but the genetic nature of the sexual system is expected to influence the evolutionary trajectories of sex-biased genes. We analyze here the patterns of sex-biased gene expression in Ectocarpus, a brown alga with haploid sex determination (dioicy) and a low level of phenotypic sexual dimorphism. In Ectocarpus, female-biased genes were found to be evolving as rapidly as male-biased genes. Moreover, genes expressed at fertility showed faster rates of evolution than genes expressed in immature gametophytes. Both male- and female-biased genes had a greater proportion of sites experiencing positive selection, suggesting that their accelerated evolution is at least partly driven by adaptive evolution. Gene duplication appears to have played a significant role in the generation of sex-biased genes in Ectocarpus, expanding previous models that propose this mechanism for the resolution of sexual antagonism in diploid systems. The patterns of sex-biased gene expression in Ectocarpus are consistent both with predicted characteristics of UV (haploid) sexual systems and with the distinctive aspects of this organism's reproductive biology. PMID:25725430

  11. SEX CHROMOSOMES IN FLOWERING PLANTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sex chromosomes in dioecious and polygamous plants evolved as a mechanism for ensuring outcrossing to increase genetic variation in the offspring. Sex specificity has evolved in 75% of plant families by male sterile or female sterile mutations, but well defined heteromorphic sex chromosomes are know...

  12. Understanding Threshold Effects of Organized Activity Involvement in Adolescents: Sex and Family Income as Moderators

    ERIC Educational Resources Information Center

    Randall, Edin T.; Bohnert, Amy M.

    2012-01-01

    The current study examined the curvilinear links between involvement in organized activities (OA) and sport activities specifically and various indicators of psychological and social development. Participants included 150 9th and 10th graders (57% females) from an urban, selective-enrollment high school. Eligibility for admission is based on city…

  13. The pharyngeal organ in the buccal cavity of the male Siamese fighting fish, Betta splendens, supplies mucus for building bubble nests.

    PubMed

    Kang, Chao-Kai; Lee, Tsung-Han

    2010-11-01

    The male Siamese fighting fish, Betta splendens, builds a bubble nest on the water surface to care for offspring during the reproductive period. To our knowledge, this study is the first to determine the composition of the bubble nest and to compare the pharyngeal organs of male and female Siamese fighting fish to determine the relationship between the pharyngeal organ and the ability to make bubble nests. Dot blots of the bubble nest probed with periodic acid-Schiff's (PAS) staining and Ponceau S solution revealed that the contents of the nest are glycoprotein rich. Dissection of the heads of Siamese fighting fish showed that the pharyngeal organ is located in the position through which inhaled air passes. The epithelial structure of the pharyngeal organ of the Siamese fighting fish, like that of other teleosts, has numerous wrinkles and papillae. Mucous goblet cells were observed on the epithelium of pharyngeal organs in male and female fish. The pharyngeal organ was found to be larger in male than in female fish. In addition, the epithelium of the pharyngeal organ in male fish has a greater number of mucous goblet cells than that in female fish. In Siamese fighting fish, this sexual dimorphism of the pharyngeal organ suggests that the male fish secretes more glycoprotein-rich mucus to build the bubble nest. Future work will focus on the type of mucous cells found in the epithelium of the pharyngeal organ that contributes to bubble formation and will determine the components of the mucus in the bubble nest. PMID:21039125

  14. Effects of adult onset mild calorie restriction on weight of reproductive organs, plasma parameters and gene expression in male mice.

    PubMed

    Rocha, J S; Bonkowski, M S; Masternak, M M; França, L R; Bartke, A

    2012-01-01

    Calorie restriction (CR) extends lifespan and delays onset of age-related diseases in various organisms, even when started later in life. Despite benefits for health and lifespan, CR's negative impact on reproduction is documented in some animals. Studies employing approximately 40% CR detected a delay in sexual maturation and impairment of fertility, which were combined with extension of the reproductive period. In contrast, mild CR (10-20%) is apparently not deleterious to reproduction. Hence, we hypothesized that mild CR started at 8 months of age would prolong reproductive capabilities and improve health parameters of male mice. To test this hypothesis, we assessed the effects of 10 and 20% CR on reproductive organ weights, selected plasma parameters and hepatic/testicular gene expression in normal male mice of heterogeneous genetic background. Starting at 8 months of age (adult), mice were assigned to 3 regimen groups: 10% CR (n = 8), 20% CR (n = 9) or ad libitum (AL; n = 8). Four months of CR were sufficient to reduce glycemia in a non-fasted protocol. Mild CR initiated in adulthood did not significantly impact final body weight, most of the analyzed plasma parameters or weight of androgen-dependent organs. Moreover, CR did not interfere with expression of the assessed testicular genes, or most of the hepatic genes, but it did cause an increase in the levels of peroxisome proliferator-activated receptor gamma (Pparg) and mouse sulfotransferase (mSTa); and a decrease in glucose-6-phosphatase-? (G6pc) mRNA, which might signify improvement of body condition. The important finding of our study was that a mild CR regimen, as low as 10 and 20%, was sufficient to impair glycemia in a non-fasted state, and also the levels of plasma IGF-1, corroborating the concept that mild CR has the potential for improving health and longevity, even when started later in life. PMID:23667390

  15. The Stability of Same-Sex Cohabitation, Different-Sex Cohabitation, and Marriage

    ERIC Educational Resources Information Center

    Lau, Charles Q.

    2012-01-01

    This study contributes to the emerging demographic literature on same-sex couples by comparing the level and correlates of union stability among 4 types of couples: (a) male same-sex cohabitation, (b) female same-sex cohabitation, (c) different-sex cohabitation, and (d) different-sex marriage. The author analyzed data from 2 British birth cohort…

  16. Homosexual behaviour increases male attractiveness to females.

    PubMed

    Bierbach, David; Jung, Christian T; Hornung, Simon; Streit, Bruno; Plath, Martin

    2013-02-23

    Male homosexual behaviour-although found in most extant clades across the Animal Kingdom-remains a conundrum, as same-sex mating should decrease male reproductive fitness. In most species, however, males that engage in same-sex sexual behaviour also mate with females, and in theory, same-sex mating could even increase male reproductive fitness if males improve their chances of future heterosexual mating. Females regularly use social information to choose a mate; e.g. male attractiveness increases after a male has interacted sexually with a female (mate choice copying). Here, we demonstrate that males of the tropical freshwater fish Poecilia mexicana increase their attractiveness to females not only by opposite-sex, but likewise, through same-sex interactions. Hence, direct benefits for males of exhibiting homosexual behaviour may help explain its occurrence and persistence in species in which females rely on mate choice copying as one component of mate quality assessment. PMID:23234866

  17. Homosexual behaviour increases male attractiveness to females

    PubMed Central

    Bierbach, David; Jung, Christian T.; Hornung, Simon; Streit, Bruno; Plath, Martin

    2013-01-01

    Male homosexual behaviour—although found in most extant clades across the Animal Kingdom—remains a conundrum, as same-sex mating should decrease male reproductive fitness. In most species, however, males that engage in same-sex sexual behaviour also mate with females, and in theory, same-sex mating could even increase male reproductive fitness if males improve their chances of future heterosexual mating. Females regularly use social information to choose a mate; e.g. male attractiveness increases after a male has interacted sexually with a female (mate choice copying). Here, we demonstrate that males of the tropical freshwater fish Poecilia mexicana increase their attractiveness to females not only by opposite-sex, but likewise, through same-sex interactions. Hence, direct benefits for males of exhibiting homosexual behaviour may help explain its occurrence and persistence in species in which females rely on mate choice copying as one component of mate quality assessment. PMID:23234866

  18. Enhancing mating performance after juvenile hormone treatment in Anastrepha fraterculus (Diptera:Tephritidae): a differential response in males and females acts as a physiological sexing system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methoprene treatment can reduce the time required for sexual maturation in Anastrepha fraterculus (Diptera: Tephritidae) (Wiedemann) males under laboratory conditions, supporting its use as a treatment for sterile males within the context of the Sterile Insect Technique (SIT). Here we evaluated sexu...

  19. Reactions to male and female success and failure in sex-linked occupations: Impressions of personality, causal attributions, and perceived likelihood of different consequences

    Microsoft Academic Search

    N. T. Feather; J. G. Simon

    1975-01-01

    48 female high school students responded to 3 short verbal cues in which either a male or female character succeeded or failed in an examination qualifying the male (or female) for entry into an occupation. 3 occupations were involved varying in masculine dominance (medicine, teaching, and nursing). In responding to each cue, Ss first rated the character in the cue

  20. A duplicated copy of DMRT1 in the sex-determining region of the Y chromosome of the medaka, Oryzias latipes

    Microsoft Academic Search

    Indrajit Nanda; Mariko Kondo; Ute Hornung; Shuichi Asakawa; Christoph Winkler; Atsushi Shimizu; Zhihong Shan; Thomas Haaf; Nobuyoshi Shimizu; Akihiro Shima; Michael Schmid; Manfred Schartl

    2002-01-01

    The genes that determine the development of the male or female sex are known in Caenorhabditis elegans, Drosophila, and most mammals. In many other organisms the existence of sex-determining factors has been shown by genetic evidence but the genes are unknown. We have found that in the fish medaka the Y chromosome-specific region spans only about 280 kb. It contains

  1. Disclosure of Male Sexual Partnering and HIV Serostatus Among a Sample of Heterosexually Identified Men Who Have Sex With Men and Women.

    PubMed

    Reback, Cathy J; Kaplan, Rachel L; Larkins, Sherry

    2015-06-01

    This study employed qualitative methods to understand better the disclosure practices of men with their male and female sexual partners. Open-ended, in-depth, semi-structured interviews were conducted with 21 heterosexually identified men who reported at least one sexual encounter with a male in the previous year but not more than one sexual encounter with a male per month. Fifty-eight percent of the participants were HIV infected. Most HIV-infected participants reported disclosure of their HIV serostatus to their female sexual partners but did not disclose that they engaged in occasional sexual encounters with a male partner. Disclosure of HIV serostatus to male sexual partners was minimal and inconsistent. PMID:26010314

  2. Brief Report: Relationship and Demographic Factors Associated With Willingness to Use an In-Home Rapid HIV Test to Screen Potential Sex Partners Among a US Sample of HIV-Negative and HIV-Discordant Male Couples.

    PubMed

    Mitchell, Jason W; Sullivan, Patrick S

    2015-06-01

    With dyadic data from a US Internet sample of 275 HIV-negative and 58 discordant male couples, we assessed HIV-negative partnered men's attitudes toward using an in-home rapid HIV test (HT) to screen potential new sex partners and associated factors by multivariate multilevel modeling. HIV-negative partnered men were "likely" to use an HT for screening purposes. More positive attitudes were associated with being in a mixed/nonwhite relationship; having an open sexual agreement. Less positive attitudes were associated with both partners being well educated. These findings may highlight how to make the most of HTs as risk-reduction screening tool among at-risk male couples. PMID:26009834

  3. Sex of child preferences among college students

    Microsoft Academic Search

    William S. Pooler

    1991-01-01

    In both 1985 and 1988, college student preferences for the sex of an only child were examined using social surveys. For both years, it was found that male students strongly prefer a male child, but that female students moderately prefer a female child. Gender of respondent accounted for most of the sex preference difference. The sex role attitude of agreement

  4. Overexpression of glutathione transferase E7 in Drosophila differentially impacts toxicity of organic isothiocyanates in males and females.

    PubMed

    Mazari, Aslam M A; Dahlberg, Olle; Mannervik, Bengt; Mannervik, Mattias

    2014-01-01

    Organic isothiocyanates (ITCs) are allelochemicals produced by plants in order to combat insects and other herbivores. The compounds are toxic electrophiles that can be inactivated and conjugated with intracellular glutathione in reactions catalyzed by glutathione transferases (GSTs). The Drosophila melanogaster GSTE7 was heterologously expressed in Escherichia coli and purified for functional studies. The enzyme showed high catalytic activity with various isothiocyanates including phenethyl isothiocyanate (PEITC) and allyl isothiocyanate (AITC), which in millimolar dietary concentrations conferred toxicity to adult D. melanogaster leading to death or a shortened life-span of the flies. In situ hybridization revealed a maternal contribution of GSTE7 transcripts to embryos, and strongest zygotic expression in the digestive tract. Transgenesis involving the GSTE7 gene controlled by an actin promoter produced viable flies expressing the GSTE7 transcript ubiquitously. Transgenic females show a significantly increased survival when subjected to the same PEITC treatment as the wild-type flies. By contrast, transgenic male flies show a significantly lower survival rate. Oviposition activity was enhanced in transgenic flies. The effect was significant in transgenic females reared in the absence of ITCs as well as in the presence of 0.15 mM PEITC or 1 mM AITC. Thus the GSTE7 transgene elicits responses to exposure to ITC allelochemicals which differentially affect life-span and fecundity of male and female flies. PMID:25329882

  5. Macrophage activity and histopathology of the lymphohematopoietic organs in male Wistar rats orally exposed to single or mixed pesticides.

    PubMed

    De Camargo, Marcela Rodrigues; Barbisan, Luís Fernando; Martinez, Meire França; Da Silva Franchi, Carla Adriene; De Camargo, João Lauro Viana; Spinardi-Barbisan, Ana Lúcia Tozzi

    2013-01-01

    The noxious effects of low or effective dose exposure to single or mixed pesticides on macrophage activity and the lymphohematopoietic organs were investigated. Male Wistar rats were orally exposed to dichlorvos, dicofol, endosulfan, dieldrin and permethrin, either as single or combined mixtures during a 28-day study containing eight groups: one group received a semipurified diet (non-treated); two groups received a semipurified diet containing low dose mixture (dieldrin 0.025 mg/kg, endosulfan, 0.6 mg/kg, dicofol 0.22 mg/kg, dichlorvos 0.23 mg/kg, permethrin 5 mg/kg) or an effective dose mixture (dichlorvos 2.3 mg/kg, dicofol 2.5 mg/kg, endosulfan 2.9 mg/kg, dieldrin 0.05 mg/kg and permethrin 25.0 mg/kg), respectively; the other five groups received a semipurified diet containing each single pesticide in effective doses. At sacrifice, the thymus, spleen, mesenteric lymph nodes, Payer's patches and bone marrow were removed for histological analysis. Peritoneal macrophages were obtained to determine the phagocytosis and spreading indexes and tumoral necrosis factor alpha (TNF-?), nitric oxide (NO) and H?O? production. Exposure to pesticide mixtures did not alter the percentage of macrophage phagocytosis and spreading, TNF-? production or the NO and H?O? release when compared to the non-treated group. Neither was there any apparent evidence that a pesticide mixture at low or effective doses altered the histological structure of the lymphohematopoietic organs. The findings indicate that short-term treatment with pesticide mixtures did not induce an apparent immunotoxic effect in male Wistar rats. PMID:23581695

  6. The relationship of male socialization and personality pathology in male batterer subtypes 

    E-print Network

    Shefferman, Lee

    2007-09-17

    This study examined the role that rigid sex-role stereotyping and male socialization played in differentiating the three typologies of male batterers. The first purpose was to utilize a cluster analysis to determine whether the three male batterer...

  7. The role of sex steroids in the regulation of insulin sensitivity and serum lipid concentrations during male puberty: a prospective study with a P450-aromatase inhibitor

    Microsoft Academic Search

    Sanna Wickman; Tero Saukkonen; Leo Dunkel

    2002-01-01

    Objective: Our purpose was to study the sex steroid-mediated changes in serum insulin and lipid concentrations in boys during puberty. Design and Methods: We treated boys with constitutional delay of puberty either with testosterone plus placebo or with testosterone plus an aromatase inhibitor, letrozole, which inhibits the conversion of androgens to oestrogens. We demonstrated previously that during treatment with testosterone

  8. THE EFFECTS OF CONTEXT, SEX, AND BODY SIZE ON STAGED SOCIAL INTERACTIONS IN JUVENILE MALE AND FEMALE GREEN ANOLES (ANOLIS CAROLINENSIS)

    Microsoft Academic Search

    Matthew B. Lovern; Thomas A. Jenssen

    2001-01-01

    Summary We documented the ontogeny of headbobbing display use in green anoles ( Anolis caroli- nensis) by determining the effects of social context, sex, and body size on juvenile social interactions. Juveniles only gave displays in social interactions (never while isolated), and activity levels in general were much higher during interactions than during isolation. Neither social context (consexual or heterosexual)

  9. A 5YearOld Boy with Cryptorchidism and Pubic Hair: Investigation and Management of Apparent Male Disorders of Sex Development in Mid-Childhood

    Microsoft Academic Search

    L. S. Keir; S. O’Toole; A. L. Robertson; A. M. Wallace; S. F. Ahmed

    2009-01-01

    Background: Late presentation of congenital adrenal hyperplasia as a 46,XX disorder of sex development due to 11-? hydroxylase deficiency is uncommon. Such a case raises issues regarding appropriate investigation and management. Case History: A 5-year-old boy who had recently moved to the United Kingdom presented at the endocrinology clinic with recurrent abdominal pain. He was normotensive and had a history

  10. Sex Chromosomes and Sex Determination in Lepidoptera

    Microsoft Academic Search

    W. Traut; K. Sahara; F. Marec

    2007-01-01

    The speciose insect order Lepidoptera (moths and butterflies) and their closest relatives, Trichoptera (caddis flies), share a female-heterogametic sex chromosome system. Originally a Z\\/ZZ (female\\/male) system, it evolved by chromosome rearrangement to a WZ\\/ZZ (female\\/male) system in the most species-rich branch of Lepidoptera, a monophyletic group consisting of Ditrysia and Tischeriina, which together comprise more than 98% of all species.

  11. Males have greater g: Sex differences in general mental ability from 100,000 17- to 18-year-olds on the Scholastic Assessment Test

    Microsoft Academic Search

    Douglas N. Jackson; J. Philippe Rushton

    2006-01-01

    In this study we found that 17- to 18-year old males averaged 3.63 IQ points higher than did their female counterparts on the 1991 Scholastic Assessment Test (SAT). We analysed 145 item responses from 46,509 males and 56,007 females (total N=102,516) using a principal components procedure. We found (1) the g factor underlies both the SAT Verbal (SAT-V) and the

  12. Sex Pheromone Traps for Monitoring the European Vine Moth, Lobesia botrana : Effect of Dispenser Type, Pheromone Dose, Field Aging of Dispenser, and Type of Trap on Male Captures

    Microsoft Academic Search

    L. Anshelevich; M. Kehat; E. Dunkelblum; S. Greenberg

    1994-01-01

    The effects of dispenser type, pheromone dose in the dispenser, aging of dispenser in the field, and trap type on trapping\\u000a efficiency of males of the European vine moth,Lobesia botrana Den. et Schiff. (Lepidoptera: Tortricidae), were investigated. LB Pherocon caps and locally manufactured septa were equally\\u000a effective in attracting males to traps. Within the range of 0.1 to 100 ?g

  13. Evolutionary transitions between mechanisms of sex determination in vertebrates

    PubMed Central

    Quinn, Alexander E.; Sarre, Stephen D.; Ezaz, Tariq; Marshall Graves, Jennifer A.; Georges, Arthur

    2011-01-01

    Sex in many organisms is a dichotomous phenotype—individuals are either male or female. The molecular pathways underlying sex determination are governed by the genetic contribution of parents to the zygote, the environment in which the zygote develops or interaction of the two, depending on the species. Systems in which multiple interacting influences or a continuously varying influence (such as temperature) determines a dichotomous outcome have at least one threshold. We show that when sex is viewed as a threshold trait, evolution in that threshold can permit novel transitions between genotypic and temperature-dependent sex determination (TSD) and remarkably, between male (XX/XY) and female (ZZ/ZW) heterogamety. Transitions are possible without substantive genotypic innovation of novel sex-determining mutations or transpositions, so that the master sex gene and sex chromosome pair can be retained in ZW–XY transitions. We also show that evolution in the threshold can explain all observed patterns in vertebrate TSD, when coupled with evolution in embryonic survivorship limits. PMID:21212104

  14. Psychological Androgyny and Male-Female Attraction.

    ERIC Educational Resources Information Center

    Orlofsky, Jacob L.

    Changes in men's and women's societal roles and in their personality characteristics might be expected to lead to corresponding changes in the personal relations between sexes. Male (N=140) and female (N=95) college students, classified as sex-typed, cross-sex-typed, androgynous, or undifferentiated on the basis of their Bem Sex Role Inventory…

  15. Sex ratios in bumble bees

    PubMed Central

    Bourke, A. F. G.

    1997-01-01

    The median proportion of investment in females among 11 populations of seven bumble bee (Bombus) species was 0.32 (range 0.07 to 0.64). By contrast, two species of workerless social parasites in the related genus Psithyrus had female-biased sex allocation, the reasons for which remain unclear. Male-biased sex allocation in Bombus contradicts the predictions of Trivers and Hare's sex ratio model for the social Hymenoptera, which are that the population sex investment ratio should be 0.5 (1:1) under queen control and 0.75 (3:1 females:males) under worker control (assuming single, once-mated, outbred queens and non-reproductive workers). Male bias in Bombus does not appear to be either an artefact, or purely the result of symbiotic sex ratio distorters. According to modifications of the Trivers–Hare model, the level of worker male-production in Bombus is insufficient to account for observed levels of male bias. There is also no evidence that male bias arises from either local resource competition (related females compete for resources) or local mate enhancement (related males cooperate in securing mates). Bulmer presented models predicting sexual selection for protandry (males are produced before females) in annual social Hymenoptera and, as a consequence (given some parameter values), male-biased sex allocation. Bumble bees fit the assumptions of Bulmer's models and are protandrous. These models therefore represent the best current explanation for the bees' male-biased sex investment ratios. This conclusion suggests that the relative timing of the production of the sexes strongly influences sex allocation in the social Hymenoptera.

  16. A Review of The Sex EDcyclopedia

    ERIC Educational Resources Information Center

    Herman, Jeff; Andelloux, Megan

    2012-01-01

    While virtually all sex education books for teenagers focus on sexual health, Jo Langford's "The Sex EDcyclopedia" offers comprehensive and empowering information specifically for teen males about their sexuality and how it may be positively experienced. This review examines the strengths of "The Sex EDcyclopedia" as a sex education resource and…

  17. Considerations of Sex, Sex Role, and Competition Anxiety.

    ERIC Educational Resources Information Center

    Wittig, Arno F.

    Recent growth of sport psychology research has led to studies of the attitudes of women in sports. Using the Bem Sex Role Inventory and the Sport Competition Anxiety Test with 736 male and female subjects, one study found that: (1) Males with a masculine self description had the lowest levels of sports anxiety; (2) The "feminine" males had a very…

  18. Attitudes about Sex Selection and Sex Preference in Iranian Couples Referred for Sex Selection Technology

    PubMed Central

    Ahmadi, Seyedeh Fatemeh; Shirzad, Mahdi; Kamali, Koorosh; Ranjbar, Fahimeh; Behjati-Ardakani, Zohreh; Akhondi, Mohammad Mehdi

    2015-01-01

    Background Gender preference is prevalent in some communities and using medical techniques to choose the baby's sex may cause the gender discrimination and gender imbalance in communities. Therefore, evaluating the gender preferences and attitudes towards using sex selection technologies seems to be necessary. Methods This cross-sectional study was conducted in Avicenna Fertility Center. Participants were 100 women with one child who were referred for sex selection. Data were collected through self-developed questionnaires. The questions were designed by the researchers at the experts’ panel. To determine the validity of the questionnaire, the viewpoints of professors specialized in these issues were obtained. The statistical analysis of the data was performed using SPSS software (Version 11.5), and p < 0.05 was considered significant. Results Tendency toward the male was more than female sex (55.5% male, 15.5% female and 28.5% no tendency). Majority of participants agreed with sex selection with medical reason and sex selection in order to balance the family. Women's level of education had positive effect on agreements to fetal sex selection with medical and non-medical reasons (p < 0.001). Conclusion Although gender preferences were toward the male sex but this preference was not very strong. Most participants agreed with non-medical sex selection for balancing the sex composition of their children. It doesn't seem that non-medical sex selection for family balancing causes severe sex imbalance in Iran. PMID:25717434

  19. From sneaker to parental male: change of reproductive traits in the black goby, Gobius niger (Teleostei, Gobiidae).

    PubMed

    Immler, Simone; Mazzoldi, Carlotta; Rasotto, Maria Berica

    2004-02-01

    This study focuses on the consequences of the switch of tactic from parasitic to parental male in the black goby, Gobius niger (Teleostei: Gobiidae), a species showing two alternative male mating tactics. Older and larger males defend nests, court, and perform parental care on eggs, while younger and smaller ones behave as parasites, sneaking into nests while spawning occurs. Males adopting different tactics are known to present differences in primary and secondary sex traits. The social context of sneaker males was manipulated to induce a tactic switch. Sneakers were kept under two different experimental treatments with or without a female, and under exclusion of male-male competition. Males changed tactics, courting females, spawning, and performing parental care. All males showed substantial changes in primary sexual traits, such as a reduction in gonadal development and an increase in the investment in accessory structures. The experimental groups differed in the functionality of gonads and accessory organs and in the development of the secondary sex traits. These results demonstrate that the moment of switching is not genetically fixed in the black goby. Sneaker males are able to quickly reallocate energy in primary and secondary sex traits, in accordance with the adopted tactic. Several aspects of this flexible reproductive pattern resemble the socially controlled sex change found in sequential hermaphrodites. PMID:14743517

  20. Sex role stereotyping in children's television programs

    Microsoft Academic Search

    Sarah H. Sternglanz; Lisa A. Serbin

    1974-01-01

    Conducted an observational analysis of the male and female role models presented on 10 popular commercially produced children's TV programs. Striking sex differences (p < .001) were found both in the number of male and female roles portrayed (more than twice as many male roles) and in the behaviors which were emitted by male and female characters. For example, males