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Sample records for male sex organ

  1. Technology, normalisation and male sex work.

    PubMed

    MacPhail, Catherine; Scott, John; Minichiello, Victor

    2015-01-01

    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

  2. Sex mosaics in a male dimorphic ant Cardiocondyla kagutsuchi

    NASA Astrophysics Data System (ADS)

    Yoshizawa, Juri; Mimori, Kohei; Yamauchi, Katsusuke; Tsuchida, Koji

    2009-01-01

    Gynandromorphy, or the development of organisms with a combination of male and female morphological features, is common in Hymenoptera. The underlying mechanism is likely associated with the sex-determination system, and studying this phenomenon should lead to a deeper understanding of both embryonic development and sex determination. The reproductive capabilities of gynandromorphs (hereafter, sex mosaics) remain unclear. We studied gynandromorphy in the Malaysian ant Cardiocondyla kagutsuchi, which has sex mosaics of queens (gynandromorphs; mosaic of queens and winged male) and workers (ergatandromorphs; mosaic of worker and wingless ergatoid male). These sex mosaics were classified into seven morphological categories. Most individuals had more male than female body areas. Behavioral observations revealed that sex mosaics behave more in accordance with the “sex” of their brain than that of the reproductive organs (gaster). Relative DNA quantities showed that both female and male regions contained haploid and diploid nuclei, irrespective of their phenotypic appearance, indicating that external appearance did not reflect internal tissues. Nearly one third of the adults were sex mosaics and they were not infected with Wolbachia. Our results suggest that the production of sex mosaics in this species does not pose a substantial cost to colonies and that the underlying causes are therefore not strongly selected against.

  3. 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

  4. Effect of housing system, slaughter weight and slaughter strategy on carcass and meat quality, sex organ development and androstenone and skatole levels in Duroc finished entire male pigs.

    PubMed

    Fàbrega, E; Gispert, M; Tibau, J; Hortós, M; Oliver, M A; Furnols, M Font I

    2011-12-01

    This study aimed at evaluating the effect of housing system (HS), slaughter weight (SW) and strategy (SS) on carcass a nd meat quality, sexual organ development and boar taint in entire males. Twelve pens of 10 pigs were used (two trials). Half of male pens were allowed visual contact with females (MF) and half with males (MM). Half MM or MF were slaughtered at 105 or 130 kg in trial 1, or penwise or by split marketing in trial 2 at 120 kg. Housing system showed no significant effect on carcass or meat quality. MF presented significantly longer testicles and heavier bulbourethral glands compared to MM. The distribution of androstenone and skatole levels was affected by SW but not by HS or SS, samples with androstenone >1 μg/g of the different groups falling within the range of 16 to 22%. All correlations between androstenone and sex organs were significant. Housing system and slaughter strategy did not reduce the risk of boar tainted carcasses. PMID:21641121

  5. Male pygmy hippopotamus influence offspring sex ratio

    PubMed Central

    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

  6. 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

  7. Estimating age: college males versus convicted male child sex offenders.

    PubMed

    Marsh, Robert; Romero, Sergio; Patrick, Steven

    2013-01-01

    Two samples, male college students and convicted male child sex offenders, are compared on their abilities to accurately estimate the age group of a series of photographs of a sole female ranging in age from 11 to 29. Both samples tend to overestimate the age group of the subject photos, and no significant difference was found between college students and convicted child sex offenders in their ability to estimate the age of females. Both groups are compared demographically, and only limited differences were found. The implications are discussed in regard to theory and prevention of child sexual abuse. PMID:24283546

  8. Sex Steroid Actions in Male Bone

    PubMed Central

    Laurent, Michaël R.; Claessens, Frank; Gielen, Evelien; Lagerquist, Marie K.; Vandenput, Liesbeth; Börjesson, Anna E.; Ohlsson, Claes

    2014-01-01

    Sex steroids are chief regulators of gender differences in the skeleton, and male gender is one of the strongest protective factors against osteoporotic fractures. This advantage in bone strength relies mainly on greater cortical bone expansion during pubertal peak bone mass acquisition and superior skeletal maintenance during aging. During both these phases, estrogens acting via estrogen receptor-α in osteoblast lineage cells are crucial for male cortical and trabecular bone, as evident from conditional genetic mouse models, epidemiological studies, rare genetic conditions, genome-wide meta-analyses, and recent interventional trials. Genetic mouse models have also demonstrated a direct role for androgens independent of aromatization on trabecular bone via the androgen receptor in osteoblasts and osteocytes, although the target cell for their key effects on periosteal bone formation remains elusive. Low serum estradiol predicts incident fractures, but the highest risk occurs in men with additionally low T and high SHBG. Still, the possible clinical utility of serum sex steroids for fracture prediction is unknown. It is likely that sex steroid actions on male bone metabolism rely also on extraskeletal mechanisms and cross talk with other signaling pathways. We propose that estrogens influence fracture risk in aging men via direct effects on bone, whereas androgens exert an additional antifracture effect mainly via extraskeletal parameters such as muscle mass and propensity to fall. Given the demographic trends of increased longevity and consequent rise of osteoporosis, an increased understanding of how sex steroids influence male bone health remains a high research priority. PMID:25202834

  9. New pleasures and old dangers: reinventing male sex work.

    PubMed

    Minichiello, Victor; Scott, John; Callander, Denton

    2013-01-01

    Understandings of male sex workers (MSWs) shift with technological, conceptual, and social changes. Research has historically constructed MSWs as psychologically unstable, desperate, or destitute victims and their clients as socially deviant perverts. These perceptions, however, are no longer supported by contemporary research and changing societal perceptions of the sex industry, challenging how we understand and describe "escorts." The changing understandings of sexuality and the increasing power of the Internet are both important forces behind recent changes in the structure and organization of MSWs. The growth in the visibility and reach of escorts has created opportunities to form an occupational account of MSWs that better accounts for the dynamic and diverse nature of the MSW experience in the early 21st century. Recent changes in the structure and organization of male sex work have provided visibility to the increasingly diverse geographical distribution of MSW, the commodification of race and racialized desire, new populations of heterosexual men and women as clients, and the successful dissemination of safer sexual messages to MSWs through online channels. This article provides a broad overview of the literature on MSWs, concentrating its focus on studies that have emerged over the past 20 years and identifying areas for future research. PMID:23480072

  10. Sex Genotype and Sex Phenotype Contribute to Growth Differences Between Male and Female Channel Catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel catfish have an XX:XY genotypic system of sex determination, and until the present study, the influence of sex genotype on growth could not be distinguished from sex phenotype. Genotypic male fish (XY) were produced by mating normal (XX) female fish with YY male fish. A subsample from eac...

  11. Is higher risk sex common among male or female youths?

    PubMed

    Berhan, Yifru; Berhan, Asres

    2015-01-01

    There are several studies that showed the high prevalence of high-risk sexual behaviors among youths, but little is known how significant the proportion of higher risk sex is when the male and female youths are compared. A meta-analysis was done using 26 countries' Demographic and Health Survey data from and outside Africa to make comparisons of higher risk sex among the most vulnerable group of male and female youths. Random effects analytic model was applied and the pooled odds ratios were determined using Mantel-Haenszel statistical method. In this meta-analysis, 19,148 male and 65,094 female youths who reported to have sexual intercourse in a 12-month period were included. The overall OR demonstrated that higher risk sex was ten times more prevalent in male youths than in female youths. The practice of higher risk sex by male youths aged 15-19 years was more than 27-fold higher than that of their female counterparts. Similarly, male youths in urban areas, belonged to a family with middle to highest wealth index, and educated to secondary and above were more than ninefold, eightfold and sixfold at risk of practicing higher risk sex than their female counterparts, respectively. In conclusion, this meta-analysis demonstrated that the practice of risky sexual intercourse by male youths was incomparably higher than female youths. Future risky sex protective interventions should be tailored to secondary and above educated male youths in urban areas. PMID:26726839

  12. Sex-Typed Attitudes, Sex-Typed Contingency Behaviors, and Personality Traits of Male Caregivers.

    ERIC Educational Resources Information Center

    Robinson, Bryan E.

    This study examined the contingency behaviors, attitudinal dispositions, and personality traits of male caregivers in day care settings. A random sample of 20 male caregivers was contrasted with 20 female caregivers and 20 male engineers on measures of sex-typed attitudes and personality traits. Male and female caregivers were also contrasted on

  13. OFFSPRING SEX RATIO IN DEER MALE REPRODUCTIVE PHYSIOLOGY AND OFFSPRING SEX RATIO IN ODOCOILEUS VIRGINIANUS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The primary sex ratio of the family Cervidae may vary at conception and/or birth from an expected 50:50 (males:females). Fertilization by X- or Y- chromosome-bearing sperm (referred to simply as X- and Y- sperm) ultimately controls the sex of offspring; however, alteration of the fetal sex ratio co...

  14. Male mutation rates and the cost of sex for females

    NASA Astrophysics Data System (ADS)

    Redfield, Rosemary J.

    1994-05-01

    ALTHOUGH we do not know why sex evolved, the twofold cost of meiosis for females provides a standard against which postulated benefits of sex can be evaluated1. The most reliable benefit is sex's ability to reduce the impact of deleterious mutations2,3. But deleterious mutations may themselves generate a large and previously overlooked female-specific cost of sex. DNA sequence comparisons have confirmed Haldane's suggestion that most mutations arise in the male germ line4,5; recent estimates of α, the ratio of male to female mutation rates, are ten, six and two in humans, primates and rodents, respectively6-8. Consequently, male gametes may give progeny more mutations than the associated sexual recombination eliminates. Here I describe computer simulations showing that the cost of male mutations can easily exceed the benefits of recombination, causing females to produce fitter progeny by parthenogenesis than by mating. The persistence of sexual reproduction by females thus becomes even more problematic.

  15. Condition dependence of male mortality drives the evolution of sex differences in longevity.

    PubMed

    Chen, Hwei-yen; Maklakov, Alexei A

    2014-10-20

    Males and females age at different rates and have different life expectancies across the animal kingdom, but what causes the longevity "gender gaps" remains one of the most fiercely debated puzzles among biologists and demographers. Classic theory predicts that the sex experiencing higher rate of extrinsic mortality evolves faster aging and reduced longevity. However, condition dependence of mortality can counter this effect by selecting against senescence in whole-organism performance. Contrary to the prevailing view but in line with an emerging new theory, we show that the evolution of sex difference in longevity depends on the factors that cause sex-specific mortality and cannot be predicted from the mortality rate alone. Experimental evolution in an obligately sexual roundworm, Caenorhabditis remanei, in which males live longer than females, reveals that sexual dimorphism in longevity erodes rapidly when the extrinsic mortality in males is increased at random. We thus experimentally demonstrate evolution of the sexual monomorphism in longevity in a sexually dimorphic organism. Strikingly, when extrinsic mortality is increased in a way that favors survival of fast-moving individuals, males evolve increased longevities, thereby widening the gender gap. Thus, sex-specific selection on whole-organism performance in males renders them less prone to the ravages of old age than females, despite higher rates of extrinsic mortality. Our results reconcile previous research with recent theoretical breakthroughs by showing that sexual dimorphism in longevity evolves rapidly and predictably as a result of the sex-specific interactions between environmental hazard and organism's condition. PMID:25308078

  16. Effects of sex chromosome aneuploidy on male sexual behavior

    PubMed Central

    Park, J. H.; Burns-Cusato, M.; Dominguez-Salazar, E.; Riggan, A.; Shetty, S.; Arnold, A. P.; Rissman, E. F.

    2008-01-01

    Incidence of sex chromosome aneuploidy in men is as high as 1:500. The predominant conditions are an additional Y chromosome (47,XYY) or an additional X chromosome (47,XXY). Behavioral studies using animal models of these conditions are rare. To assess the role of sex chromosome aneuploidy on sexual behavior, we used mice with a spontaneous mutation on the Y chromosome in which the testis-determining gene Sry is deleted (referred to as Y?) and insertion of a Sry transgene on an autosome. Dams were aneuploid (XXY?) and the sires had an inserted Sry transgene (XYSry). Litters contained six male genotypes, XY, XYY?, XXSry, XXY?Sry, XYSry and XYY?Sry. In order to eliminate possible differences in levels of testosterone, all of the subjects were castrated and received testosterone implants prior to tests for male sex behavior. Mice with an additional copy of the Y? chromosome (XYY?) had shorter latencies to intromit and achieve ejaculations than XY males. In a comparison of the four genotypes bearing the Sry transgene, males with two copies of the X chromosome (XXSry and XXY?Sry) had longer latencies to mount and thrust than males with only one copy of the X chromosome (XYSry and XYY?Sry) and decreased frequencies of mounts and intromissions as compared with XYSry males. The results implicate novel roles for sex chromosome genes in sexual behaviors. PMID:18363850

  17. Sex-specific inbreeding depression depends on the strength of male-male competition.

    PubMed

    Janicke, Tim; Vellnow, Nikolas; Sarda, Violette; David, Patrice

    2013-10-01

    Inbreeding depression has become a central theme in evolutionary biology and is considered to be a driving force for the evolution of reproductive morphology, physiology, behavior, and mating systems. Despite the overwhelming body of empirical work on the reproductive consequences of inbreeding, relatively little is known on whether inbreeding depresses male and female fitness to the same extent. However, sex-specific inbreeding depression has been argued to affect the evolution of selfing rates in simultaneous hermaphrodites and provides a powerful approach to test whether selection is stronger in males than in females, which is predicted to be the consequence of sexual selection. We tested for sex-specific inbreeding depression in the simultaneously hermaphroditic freshwater snail Physa acuta by comparing the reproductive performance of both sex functions between selfed and outcrossed focal individuals under different levels of male-male competition. We found that inbreeding impaired both male and female reproductive success and that the magnitude of male inbreeding depression exceeded female inbreeding depression when the opportunity for sperm competition was highest. Our study provides the first evidence for sex-specific inbreeding depression in a hermaphroditic animal and highlights the importance of considering the level of male-male competition when assessing sex differences in inbreeding depression. PMID:24094339

  18. The evolution of sex chromosomes in organisms with separate haploid sexes.

    PubMed

    Immler, Simone; Otto, Sarah Perin

    2015-03-01

    The evolution of dimorphic sex chromosomes is driven largely by the evolution of reduced recombination and the subsequent accumulation of deleterious mutations. Although these processes are increasingly well understood in diploid organisms, the evolution of dimorphic sex chromosomes in haploid organisms (U/V) has been virtually unstudied theoretically. We analyze a model to investigate the evolution of linkage between fitness loci and the sex-determining region in U/V species. In a second step, we test how prone nonrecombining regions are to degeneration due to accumulation of deleterious mutations. Our modeling predicts that the decay of recombination on the sex chromosomes and the addition of strata via fusions will be just as much a part of the evolution of haploid sex chromosomes as in diploid sex chromosome systems. Reduced recombination is broadly favored, as long as there is some fitness difference between haploid males and females. The degeneration of the sex-determining region due to the accumulation of deleterious mutations is expected to be slower in haploid organisms because of the absence of masking. Nevertheless, balancing selection often drives greater differentiation between the U/V sex chromosomes than in X/Y and Z/W systems. We summarize empirical evidence for haploid sex chromosome evolution and discuss our predictions in light of these findings. PMID:25582562

  19. The Male Sex Role: A Selected and Annotated Bibliography.

    ERIC Educational Resources Information Center

    Grady, Kathleen E.; And Others

    This bibliography, containing more than 250 entries, presents research and theoretical perspectives into the male sex role. Articles were chosen for their usefulness to researchers, with emphasis on scientific and data-based research literature. All the annotations use a standard format including subjects, method, findings and comments. Articles

  20. Males on demand: the environmental-neuro-endocrine control of male sex determination in daphnids.

    PubMed

    LeBlanc, Gerald A; Medlock, Elizabeth K

    2015-11-01

    Branchiopod crustaceans (e.g., Daphnia sp.) and some other taxa utilize both asexual and sexual reproduction to maximize population sustainability. The decision to switch from asexual to sexual reproduction is triggered by environmental cues that foretell a potentially detrimental change in environmental conditions. This review describes the cascade of events beginning with environmental cues and ending with changes in gene expression that dictate male sex determination in daphnids, the initial event in the switch to sexual reproduction. Several environmental cues have been identified which, either in isolation or in combination, stimulate male sex determination. These cues are typically associated with change of season, exhaustion of resources or loss of habitat. Maternal daphnids receive and respond to these cues, we propose, through the secretion of neuropeptides, which suppress (hyperglycemic hormone-like neuropeptides, allatostatin) or stimulate (allatotropin) the male sex differentiation program. In response, maternal daphnids produce the male sex-determining hormone, methyl farnesoate. Methyl farnesoate binds to a protein MET that dimerizes with the protein SRC forming an active transcription factor. This complex then regulates the expression of genes, primarily doublesex (dsx), involved in programming the single-celled embryo to develop into a male. In the absence of methyl farnesoate programming, the embryo develops into a female. Epigenetic modifications of the genome as a possible mode of methyl farnesoate action and the utility of this model to decipher the role of epigenetics in sex differentiation in other species are discussed. PMID:26237283

  1. An inhibitory sex pheromone tastes bitter for Drosophila males.

    PubMed

    Lacaille, Fabien; Hiroi, Makoto; Twele, Robert; Inoshita, Tsuyoshi; Umemoto, Daisuke; Manire, Grard; Marion-Poll, Frdric; Ozaki, Mamiko; Francke, Wittko; Cobb, Matthew; Everaerts, Claude; Tanimura, Teiichi; Ferveur, Jean-Franois

    2007-01-01

    Sexual behavior requires animals to distinguish between the sexes and to respond appropriately to each of them. In Drosophila melanogaster, as in many insects, cuticular hydrocarbons are thought to be involved in sex recognition and in mating behavior, but there is no direct neuronal evidence of their pheromonal effect. Using behavioral and electrophysiological measures of responses to natural and synthetic compounds, we show that Z-7-tricosene, a Drosophila male cuticular hydrocarbon, acts as a sex pheromone and inhibits male-male courtship. These data provide the first direct demonstration that an insect cuticular hydrocarbon is detected as a sex pheromone. Intriguingly, we show that a particular type of gustatory neurons of the labial palps respond both to Z-7-tricosene and to bitter stimuli. Cross-adaptation between Z-7-tricosene and bitter stimuli further indicates that these two very different substances are processed by the same neural pathways. Furthermore, the two substances induced similar behavioral responses both in courtship and feeding tests. We conclude that the inhibitory pheromone tastes bitter to the fly. PMID:17710124

  2. 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.

  3. Converging Evidence of Ubiquitous Male Bias in Human Sex Perception

    PubMed Central

    Gaetano, Justin; van der Zwan, Rick; Oxner, Matthew; Hayward, William G.; Doring, Natalie; Blair, Duncan; Brooks, Anna

    2016-01-01

    Visually judging the sex of another can be achieved easily in most social encounters. When the signals that inform such judgements are weak (e.g. outdoors at night), observers tend to expect the presence of males–an expectation that may facilitate survival-critical decisions under uncertainty. The present aim was to examine whether this male bias depends on expertise. To that end, Caucasian and Asian observers targeted female and male hand images that were either the same or different to the observers’ race (i.e. long term experience was varied) while concurrently, the proportion of targets changed across presentation blocks (i.e. short term experience change). It was thus found that: (i) observers of own-race stimuli were more likely to report the presence of males and absence of females, however (ii) observers of other-race stimuli–while still tending to accept stimuli as male–were not prone to rejecting female cues. Finally, (iii) male-biased measures did not track the relative frequency of targets or lures, disputing the notion that male bias derives from prior expectation about the number of male exemplars in a set. Findings are discussed in concert with the pan-stimulus model of human sex perception. PMID:26859570

  4. Sex work in Mexico: vulnerability of male, travesti, transgender and transsexual sex workers.

    PubMed

    Infante, Cesar; Sosa-Rubi, Sandra G; Cuadra, Silvia Magali

    2009-02-01

    In Mexico, male sex workers (MSW) and travesti, transgender and transsexual (TTT) sex workers are among the groups most affected by HIV. They suffer from stigma and discrimination, yet are often absent from the design of programmes and HIV prevention campaigns. The objective of this study was to provide an account of the social context in which MSW and TTT sex workers live, by focusing on their sexual identities, sexual practices and vulnerability to HIV. Data collection took place in Mexico City and involved observational work together with 36 in-depth interviews. Findings reveal a differentiation of vulnerability by sub-group. In general, vulnerability is influenced by the social context, stigma related to homosexuality and sex work, as well as sex workers' access to scarce social capital and the lack of response in terms of social and health programmes. In order to diminish the vulnerability of MSW and TTT sex workers and reduce their risk of HIV infection, preventive measures are needed which take into account their specific health and social needs, promote meaningful participation and the encourage respect for human rights. PMID:19140056

  5. The social meanings behind male sex work: implications for sexual interactions.

    PubMed

    Browne, J; Minichiello, V

    1995-12-01

    This qualitative study explores the meanings of the commercial sexual encounter between male sex workers and their clients. The study highlights the various social meanings male sex workers attribute to having sex, their typologies of clients, the psychic contexts of male commercial sex, safer sex interactions, and how these issues inform sexual behaviour. The data shows that the meaning attached to the act of having sex is an important aspect of the way in which participants perceive their partners, conduct themselves during sexual encounters, and engage in safe sex practices. Clients are categorized by sex workers according to their perceptions of 'them', which include 'marrieds', 'easy trade', 'undesirables', 'sugar daddies' and 'heaven trade'. Different types of clients pose alternate levels of risk to the safe sex practices of sex workers. The sex worker's definition of commercial sex as work enables him to separate work and personal sex and define work sex as 'not real sex', in which safe sex practices symbolize both the degree of self that is shared and protective work equipment. It was also found that this sample of sex workers do not negotiate safe sex. Rather they use 'modes of interaction' which direct the encounter either towards safe sex, or they refuse to continue with the transaction. The interactive modes identified are 'natural', 'educative', 'challenge', 'other options' and 'walk-out'. These modes of interaction are effective strategies for ensuring safe sex, and can be used by the broader community to gain partner compliance in safe sex practices. PMID:7493152

  6. HIV behavioural risks and the role of work environment among Chinese male sex workers in Hong Kong.

    PubMed

    Wong, William C W; Leung, Phil W S; Li, C W

    2012-01-01

    Male sex workers are a highly marginalised group in Hong Kong and it is increasingly so with an influx of them travelling from mainland China to work as "freelance" sex workers. This study aimed to measure important work environment variables that might affect the likelihood of condom use among male sex workers working in Hong Kong. A cross-sectional survey of 161 participants recruited by snowball and convenience sampling methods through outreach workers of a local non-governmental organization was conducted in 2007-2008. Only 27.4%, 54.7% and 42.6% reported consistent condom use when engaging in oral, anal and vaginal sex, respectively. Logistic regression shows unsafe sex was nearly four times (OR=3.41; 95%CI 1.51-7.69) as common in institutionalised male sex workers as among their independent counterparts. Lack of condoms provided at workplaces was a major barrier in this socio-legal context and was strongly associated with condom non-use amongst institutionalised sex workers (OR= 10.86; 95%CI 2.94-40.17). The present study finds that when compared with independent Male sex workers (MSWs), institutionalised MSWs were older, less educated, earned a higher income but more likely to engage in unsafe sex with their clients and their partners. Public health physicians must work with law-enforcing authorities to provide clear guidelines to remove these HIV prevention barriers. PMID:22293067

  7. Sex and the unspoken in male street prostitution.

    PubMed

    Kaye, Kerwin

    2007-01-01

    Although the overwhelming majority of male prostitutes work through agencies or by placing their own ads, most studies of male prostitution focus upon young men who work on the street. Remarkably, these studies seldom identify the dynamics of poverty and street-level violence as important elements of their examination. Investigations of male sex work-few though they are-focus almost exclusively upon sexual aspects of "the life." Despite the importance of these networks in shaping the contours of street life, and often in enabling one's very survival, the primary research focus has remained on questions of sexual identity, sexual practices with clients, and sexual abuse as a causative factor. Meanwhile, studies that do examine the dynamics of male street life typically do not examine questions of prostitution or other issues related to sexuality. A dominant theme within this literature consists of specifying the social mores of the most aggressive and socially problematic participants within street society, particularly gang members and drug dealers. The dissimilar nature of these images relates directly to the political projects of the dominant culture, which, in a very general way, seeks to "rescue" (reintegrate) deviant white youth, while controlling and excluding deviant youth of color. The political aim of reintegrating runaways into middle-class trajectories has the effect of authorizing certain discourses regarding their behavior on the streets, while marginalizing or completely disallowing others. This article seeks to examine and challenge these trends of representation. PMID:18019069

  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. 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 (17β-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 17β-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 (17β-estradiol in this case) underlies expression of the male phenotype. PMID:22323194

  10. Effects of α-zearalanol on spermatogenesis and sex hormone levels of male mice

    PubMed Central

    Bo, Cunxiang; Zhao, Wei; Jia, Qiang; Yang, Zhifeng; Sai, Linlin; Zhang, Fang; Du, Zhongjun; Yu, Gongchang; Xie, Lin; Zhang, Zhenling

    2015-01-01

    Aims: To investigate the mechanisms of α-zearalanol (Zeranol)-induced male reproductive toxicity, the effects of Zeranol on spermatogenesis and sex hormone levels of male mice were studied. Methods: Forty healthy sexually mature male Kunming mice were randomly divided into four groups. The mice were mock-treated or treated with Zeranol 25, 50 or 100 mg/kg via oral gavage for 35 days. The epididymal sperms were counted and their morphology and motility were analyzed. The testicles were examined by light and electron microscopy. The levels of serum/testicular testosterone (T), serum follicle stimulating hormone (FSH) and serum luteinizing hormone (LH) were determined by radioimmunoassay. Results: Zeranol decreased the epididymal sperm count and sperm motility in a dose depend manner. While there were not significant differences in the sperm malformation rates between the Zeranol treated groups and the control group. Furthermore, Zeranol could decrease the weight and the organ coefficient of the seminal vesicles and the testicles and lead to significant pathological changes of the testicles. Zeranol could also decrease the levels of serum T, FSH, LH as well as the levels of testicular T of male mice. Conclusions: Zeranol induced reproductive toxicity in adult male mice. It could damage spermatogenesis via its direct effects on the testicles and interfere with sex hormone levels of male mice through its effects on the hypothalamic-pituitary-testicular axis. PMID:26884912

  11. Non-Mendelian segregation of sex chromosomes in heterospecific Drosophila males.

    PubMed

    Dermitzakis, E T; Masly, J P; Waldrip, H M; Clark, A G

    2000-02-01

    Interspecific hybrids and backcrossed organisms generally suffer from reduced viability and/or fertility. To identify and genetically map these defects, we introgressed regions of the Drosophila sechellia genome into the D. simulans genome. A female-biased sex ratio was observed in 24 of the 221 recombinant inbred lines, and subsequent tests attributed the skew to failure of Y-bearing sperm to fertilize the eggs. Apparently these introgressed lines fail to suppress a normally silent meiotic drive system. Using molecular markers we mapped two regions of the Drosophila genome that appear to exhibit differences between D. simulans and D. sechellia in their regulation of sex chromosome segregation distortion. The data indicate that the sex ratio phenotype results from an epistatic interaction between at least two factors. We discuss whether this observation is relevant to the meiotic drive theory of hybrid male sterility. PMID:10655222

  12. 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

  13. Sex and species recognition by wild male southern white rhinoceros using contact pant calls.

    PubMed

    Cinková, Ivana; Policht, Richard

    2016-03-01

    Recognition of information from acoustic signals is crucial in many animals, and individuals are under selection pressure to discriminate between the signals of conspecifics and heterospecifics or males and females. Here, we first report that rhinos use information encoded in their calls to assess conspecifics and individuals of closely related species. The southern (Ceratotherium simum) and critically endangered northern (C. cottoni) white rhinos are the most social out of all the rhinoceros species and use a contact call pant. We found that southern white rhino pant calls provide reliable information about the caller's sex, age class and social situation. Playback experiments on wild territorial southern white rhinoceros males revealed that they responded more strongly to the pant calls of conspecific females compared to the calls of other territorial males. This suggests that pant calls are more important form of communication between males and females than between territorial males. Territorial southern males also discriminated between female and territorial male calls of northern species and reacted more intensively to the calls of northern than southern males. This might be caused by a novelty effect since both species naturally live in allopatry. We conclude that white rhinos can directly benefit from assessing individuals at long distances using vocal cues especially because their eyesight is poor. Pant calls thus likely play a significant role in their social relationships and spatial organization. In addition, better understanding of vocal communication in white rhinos might be helpful in conservation management particularly because of their low reproduction in captivity. PMID:26577089

  14. Female-to-male sex reversal in mice caused by transgenic overexpression of Dmrt1.

    PubMed

    Zhao, Liang; Svingen, Terje; Ng, Ee Ting; Koopman, Peter

    2015-03-15

    Genes related to Dmrt1, which encodes a DNA-binding DM domain transcription factor, act as triggers for primary sex determination in a broad range of metazoan species. However, this role is fulfilled in mammals by Sry, a newly evolved gene on the Y chromosome, such that Dmrt1 has become dispensable for primary sex determination and instead maintains Sertoli cell phenotype in postnatal testes. Here, we report that enforced expression of Dmrt1 in XX mouse fetal gonads using a Wt1-BAC transgene system is sufficient to drive testicular differentiation and male secondary sex development. XX transgenic fetal gonads showed typical testicular size and vasculature. Key ovarian markers, including Wnt4 and Foxl2, were repressed. Sertoli cells expressing the hallmark testis-determining gene Sox9 were formed, although they did not assemble into normal testis cords. Other bipotential lineages differentiated into testicular cell types, including steroidogenic fetal Leydig cells and non-meiotic germ cells. As a consequence, male internal and external reproductive organs developed postnatally, with an absence of female reproductive tissues. These results reveal that Dmrt1 has retained its ability to act as the primary testis-determining trigger in mammals, even though this function is no longer normally required. Thus, Dmrt1 provides a common thread in the evolution of sex determination mechanisms in metazoans. PMID:25725066

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

    PubMed

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

    2007-12-01

    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

  16. Autosomal gsdf acts as a male sex initiator in the fish medaka.

    PubMed

    Zhang, Xi; Guan, Guijun; Li, Mingyou; Zhu, Feng; Liu, Qizhi; Naruse, Kiyoshi; Herpin, Amaury; Nagahama, Yoshitaka; Li, Jiale; Hong, Yunhan

    2016-01-01

    Sex is pivotal for reproduction, healthcare and evolution. In the fish medaka, the Y-chromosomal dmy (also dmrt1bY) serves the sex determiner, which activates dmrt1 for male sex maintenance. However, how dmy makes the male decision via initiating testicular differentiation has remained unknown. Here we report that autosomal gsdf serves a male sex initiator. Gene addition and deletion revealed that gsdf was necessary and sufficient for maleness via initiating testicular differentiation. We show that gsdf transcription is activated directly by dmy. These results establish the autosomal gsdf as the first male sex initiator. We propose that dmy determines maleness through activating gsdf and dmrt1 without its own participation in developmental processes of sex initiation and maintenance. gsdf may easily become a sex determiner or other autosomal genes can be recruited as new sex determiners to initiate gsdf expression. Our findings offer new insights into molecular mechanisms underlying sex development and evolution of sex-controlling genes in vertebrates. PMID:26813267

  17. Autosomal gsdf acts as a male sex initiator in the fish medaka

    PubMed Central

    Zhang, Xi; Guan, Guijun; Li, Mingyou; Zhu, Feng; Liu, Qizhi; Naruse, Kiyoshi; Herpin, Amaury; Nagahama, Yoshitaka; Li, Jiale; Hong, Yunhan

    2016-01-01

    Sex is pivotal for reproduction, healthcare and evolution. In the fish medaka, the Y-chromosomal dmy (also dmrt1bY) serves the sex determiner, which activates dmrt1 for male sex maintenance. However, how dmy makes the male decision via initiating testicular differentiation has remained unknown. Here we report that autosomal gsdf serves a male sex initiator. Gene addition and deletion revealed that gsdf was necessary and sufficient for maleness via initiating testicular differentiation. We show that gsdf transcription is activated directly by dmy. These results establish the autosomal gsdf as the first male sex initiator. We propose that dmy determines maleness through activating gsdf and dmrt1 without its own participation in developmental processes of sex initiation and maintenance. gsdf may easily become a sex determiner or other autosomal genes can be recruited as new sex determiners to initiate gsdf expression. Our findings offer new insights into molecular mechanisms underlying sex development and evolution of sex-controlling genes in vertebrates. PMID:26813267

  18. A Prospective Analysis of Juvenile Male Sex Offenders: Characteristics and Recidivism Rates as Adults

    ERIC Educational Resources Information Center

    Vandiver, Donna M.

    2006-01-01

    This research assesses the recidivism rates of a sample of 300 registered male sex offenders who were juveniles at the time of their initial arrest for a sex offense. This sample is followed for 3 to 6 years after they reached adulthood; recidivism rates are assessed during their adulthood only. The typical juvenile is a 15-year-old Caucasian male

  19. Sex-Role Identification of Normal Adolescent Males and Females as Related to School Achievement.

    ERIC Educational Resources Information Center

    Hock, Robert A.; Curry, John F.

    1983-01-01

    This study examines the sex-role perceptions that adolescents hold of fathers, mothers, ideal males, ideal females, and selves. Differences exist between male and female adolescents, and significant linkages exist between sex-role identification and academic achievement. (Author/BW)

  20. Heterosexuals' Attitudes toward Lesbianism and Male Homosexuality: Their Affective Orientation toward Sexuality and Sex Guilt.

    ERIC Educational Resources Information Center

    Yarber, William L.; Yee, Bernadette

    1983-01-01

    A study sought to determine if a relationship existed between heterosexual college students' attitudes toward lesbianism and male homosexuality and their feelings about their own sexuality, including sex guilt. High sex guilt proved to be related to negative attitudes toward homosexuals of both sexes. (Authors/PP)

  1. Male Clients of Male Sex Workers in China: An Ignored High-Risk Population

    PubMed Central

    Chen, Lei; Mahapatra, Tanmay; Fu, Gengfeng; Huang, Shujie; Zheng, Heping; Tucker, Joseph D.; Yang, Bin; Zhao, Jinkou; Detels, Roger

    2016-01-01

    Background: There is a high prevalence of HIV/syphilis among male sex workers, but no formal study has ever been conducted focusing on male clients of male sex workers (MCM). A detailed investigation was thus called for, to determine the burden and sociobehavioral determinants of HIV and syphilis among these MCM in China. Methods: As part of a multicenter cross-sectional study, using respondent-driven and snowball sampling, 2958 consenting adult men who have sex with men (MSM) were recruited, interviewed, and tested for HIV and syphilis between 2008 and 2009. The distributions of sociodemographic characteristics, risk behaviors, and HIV/syphilis prevalence were determined and compared between MCM and other MSM. Results: Among recruited MSM, 5.0% (n = 148) were MCM. HIV prevalences for MCM and other MSM were 7.4% and 7.7%, whereas 18.9% and 14.0% were positive for syphilis, respectively. Condomless anal intercourse (CAI) was reported by 59.5% of MCM and 48.2% of MSM. Multiple logistic regression revealed that compared with other MSM, MCM were more likely to have less education [for ≤elementary level, adjusted odds ratio (aOR) = 3.13, 95% confidence interval (95% CI): 1.42 to 6.90], higher income (for >500 US Dollars per month, aOR = 2.97, 95% CI: 1.53 to 5.77), more often found partners at parks/restrooms (aOR = 4.01, 95% CI: 2.34 to 6.85), reported CAI (aOR = 1.49, 95% CI: 1.05 to 2.10), reported a larger sexual network (for ≥10, aOR = 2.70, 95% CI: 1.44 to 5.07), and higher odds of syphilis (aOR = 1.54, 95% CI: 1.00 to 2.38). Conclusions: The greater frequency of risk behaviors and high prevalence of HIV and syphilis indicated that HIV/syphilis prevention programs in China need to pay special attention to MCM as a distinct subgroup, which was completely ignored until date. PMID:26871882

  2. 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

  3. Male-male contests for mates, sexual size dimorphism, and sex ratio in a natural population of a solitary parasitoid.

    PubMed

    Macedo, Margarete V; Monteiro, Ricardo F; Silveira, Mariana P; Mayhew, Peter J

    2013-11-01

    Understanding how different behavioural and life history traits interact is fundamental to developing ethological theory. Here we study the interaction of male-male competition for mates and sexual size dimorphism in a solitary wasp, with implications for sex allocation. In Hymenoptera, females are normally larger than males suggesting that males do not benefit as much as females from larger size. However, in our focal species, a solitary Eurytoma wasp, males compete for mates by pairwise contests at female emergence sites, suggesting that male size may strongly affect fitness. In contests observed in the field, larger males were more likely to win fights, and males fighting at female emergence sites were much larger than average males. Males showed higher variance in body size than females, such that all the smallest individuals were males, a majority of medium-to-large individuals were female, but the majority of largest individuals were male. Our data suggest that sexual size dimorphism in this species has been affected by intra-sexual selection for male size, which may have implications for sex allocation. PMID:23872503

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

    SciTech Connect

    Rosenmai, A.K.; Nielsen, F.K.; Pedersen, M.; Hadrup, N.; Trier, X.; Christensen, J.H.; Vinggaard, A.M.

    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 17β-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.

  5. 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)

  6. 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

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

    PubMed Central

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

    2013-01-01

    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 vs. 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

  8. 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

  9. '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

  10. “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

  11. 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

  12. 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)

  13. No Need to Discriminate? Reproductive Diploid Males in a Parasitoid with Complementary Sex Determination

    PubMed Central

    Elias, Jan; Mazzi, Dominique; Dorn, Silvia

    2009-01-01

    Diploid males in hymenopterans are generally either inviable or sterile, thus imposing a severe genetic load on populations. In species with the widespread single locus complementary sex determination (sl-CSD), sex depends on the genotype at one single locus with multiple alleles. Haploid (hemizygous) individuals are always males. Diploid individuals develop into females when heterozygous and into males when homozygous at the sex determining locus. Our comparison of the mating and reproductive success of haploid and diploid males revealed that diploid males of the braconid parasitoid Cotesia glomerata sire viable and fertile diploid daughters. Females mated to diploid males, however, produced fewer daughters than females mated to haploid males. Nevertheless, females did not discriminate against diploid males as mating partners. Diploid males initiated courtship display sooner than haploid males and were larger in body size. Although in most species so far examined diploid males were recognized as genetic dead ends, we present a second example of a species with sl-CSD and commonly occurring functionally reproductive diploid males. Our study suggests that functionally reproductive diploid males might not be as rare as hitherto assumed. We argue that the frequent occurrence of inbreeding in combination with imperfect behavioural adaptations towards its avoidance promote the evolution of diploid male fertility. PMID:19551142

  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. Prevalence and Behavioral Correlates of Depression and Anxiety Among Male Sex Workers in Vietnam

    PubMed Central

    Goldsamt, Lloyd A.; Clatts, Michael C.; Giang, Le Minh; Yu, Gary

    2015-01-01

    Objectives This study assessed depression and anxiety symptoms, and their association with high-risk sexual and drug behaviors, among male sex workers in three Vietnamese cities. Methods Male sex workers ages 16 to 35 completed an interview that included the CES-D to assess depressive symptoms and the BAI to assess anxiety symptoms, as well as questions assessing drug and sexual risk practices. Results A majority of participants reported depressive symptomatology although fewer report symptoms of anxiety. Risky sexual and drug use practices predicted both types of symptoms. Conclusions Mental distress is associated with drug and sexual risk among male sex workers. PMID:25984252

  16. The Weaker Sex? The Propensity for Male-Biased Piglet Mortality

    PubMed Central

    Baxter, Emma M.; Jarvis, Susan; Palarea-Albaladejo, Javier; Edwards, Sandra A.

    2012-01-01

    For the most part solutions to farm animal welfare issues, such as piglet mortality, are likely to lie within the scientific disciplines of environmental design and genetic selection, however understanding the ecological basis of some of the complex dynamics observed between parent and offspring could make a valuable contribution. One interesting, and often discussed, aspect of mortality is the propensity for it to be sex-biased. This study investigated whether known physiological and behavioural indicators of piglet survival differed between the sexes and whether life history strategies (often reported in wild or feral populations) relating to parental investment were being displayed in a domestic population of pigs. Sex ratio (proportion of males (males/males+females)) at birth was 0.54 and sex allocation (maternal investment measured as piglet birth weight/litter weight) was statistically significantly male-biased at 0.55 (t35?=?2.51 P?=?0.017), suggesting that sows invested more in sons than daughters during gestation. Despite this investment in birth weight, a known survival indicator, total pre-weaning male mortality was statistically significantly higher than female mortality (12% vs. 7% respectively z?=?2.06 P?=?0.040). Males tended to suffer from crushing by the sow more than females and statistically significantly more males died from disease-related causes. Although males were born on average heavier, with higher body mass index and ponderal index, these differences were not sustained. In addition male piglets showed impaired thermoregulation compared to females. These results suggest male-biased mortality exists despite greater initial maternal investment, and therefore reflects the greater susceptibility of this sex to causal mortality factors. Life history strategies are being displayed by a domestic population of pigs with sows in this study displaying a form of parental optimism by allocating greater resources at birth to males and providing an over-supply of this more vulnerable sex in expectation of sex-biased mortality. PMID:22272334

  17. The weaker sex? The propensity for male-biased piglet mortality.

    PubMed

    Baxter, Emma M; Jarvis, Susan; Palarea-Albaladejo, Javier; Edwards, Sandra A

    2012-01-01

    For the most part solutions to farm animal welfare issues, such as piglet mortality, are likely to lie within the scientific disciplines of environmental design and genetic selection, however understanding the ecological basis of some of the complex dynamics observed between parent and offspring could make a valuable contribution. One interesting, and often discussed, aspect of mortality is the propensity for it to be sex-biased. This study investigated whether known physiological and behavioural indicators of piglet survival differed between the sexes and whether life history strategies (often reported in wild or feral populations) relating to parental investment were being displayed in a domestic population of pigs. Sex ratio (proportion of males (males/males+females)) at birth was 0.54 and sex allocation (maternal investment measured as piglet birth weight/litter weight) was statistically significantly male-biased at 0.55 (t(35)?=?2.51 P?=?0.017), suggesting that sows invested more in sons than daughters during gestation. Despite this investment in birth weight, a known survival indicator, total pre-weaning male mortality was statistically significantly higher than female mortality (12% vs. 7% respectively z?=?2.06 P?=?0.040). Males tended to suffer from crushing by the sow more than females and statistically significantly more males died from disease-related causes. Although males were born on average heavier, with higher body mass index and ponderal index, these differences were not sustained. In addition male piglets showed impaired thermoregulation compared to females. These results suggest male-biased mortality exists despite greater initial maternal investment, and therefore reflects the greater susceptibility of this sex to causal mortality factors. Life history strategies are being displayed by a domestic population of pigs with sows in this study displaying a form of parental optimism by allocating greater resources at birth to males and providing an over-supply of this more vulnerable sex in expectation of sex-biased mortality. PMID:22272334

  18. Sexual hazards, life experiences and social circumstances among male sex workers in Nigeria.

    PubMed

    Okanlawon, Kehinde; Adebowale, Ayo Stephen; Titilayo, Ayotunde

    2013-01-01

    The sexual health and rights needs of male sex workers in Nigeria remain poorly understood and served. Men who sell sex are at high risk of discrimination and violation because of laws criminalising same-sex activity and sex work. This paper examines the experiences, social circumstances, vulnerabilities and sexual hazards experienced by male sex workers in Nigeria. In-depth interviews were used to explore the experiences of six male sex workers who were selected by means of convenience sampling from among those who came for counselling. Findings reveal that economic disadvantage drives some men to engage in sex work and risky sexual behaviour. Subsequently, sex work may put their lives and health at risk as a result of violation by the police and clients, including ritual murder. Men's extreme vulnerability points to the need for appropriate interventions to improve well-being. Sexual health and rights programmes must identify ways of making male sex workers less vulnerable to abuse, and devise strategies for protecting their health and human rights, while empowering them economically to reduce their dependency on often risky sexual behaviour for livelihoods. PMID:23252939

  19. Functional development of sex accessory organs of the male rat. Use of oestradiol benzoate to identify the neonatal period as critical for development of normal protein-synthetic and secretory capabilities.

    PubMed Central

    Higgins, S J; Brooks, D E; Fuller, F M; Jackson, P J; Smith, S E

    1981-01-01

    Functional development of the sex accessory tissues was studied in the male rat. Three potentially crucial developmental periods (neonatal, prepubertal and pubertal) were examined, and then the functional integrity of the accessory tissues was investigated in the adult, when the animals would have been expected to display normal function. Four accessory tissues (the seminal vesicles, ventral prostate and caput and cauda epididymides) were used because of their different embryological origins and responses to androgens in the adult. Synthesis and secretion of previously characterized tissue-specific androgen-dependent proteins were taken as indicators of normal function. Development was perturbed by using oestradiol benzoate, since this was known to affect gross development of the seminal vesicles and ventral prostate when given to neonatal rats. Treatment during the first 5 days after birth severely restricted development of the seminal vesicles and ventral prostate. Protein secreted by the former was only 1% of the normal amount, and in many cases several major secretory proteins were essentially missing. Prostatic protein secretion was less than 20% of normal, but all the major proteins were detectable. In both tissues overall protein synthesis per cell was quantitatively normal, but the proportion devoted to specific major secretory proteins was markedly depressed, i.e. the response is differential. In contrast, treatment during the prepubertal period was without noticeable effects. Development of the seminal vesicles and prostate was somewhat inhibited by treatment at puberty, but these changes were minor compared with those after neonatal exposure to oestradiol benzoate. No effects on epididymal protein synthesis or secretory proteins were observed, and epididymal weight and DNA content were only moderately decreased regardless of when oestradiol benzoate was administered during sexual maturation. Hence the neonatal period is not so critical for epididymal development. The substantial changes elicited by oestrogen treatment during neonatal life in seminal-vesicle and prostatic protein synthesis and secretion were compared with those evoked in sexually mature males by either oestrogen treatment or castration. Both these latter treatments resulted in a general decrease in seminal-vesicle protein synthesis and secretion, but the marked differential effects on major proteins after neonatal exposure were absent. Castration did, however, evoke a differential prostatic response, but this was not seen after oestrogen treatment of adults. Images Fig. 1. Fig. 2. PMID:7306031

  20. Discordant Sexual Identity in Some Genetic Males with Cloacal Exstrophy Assigned to Female Sex at Birth

    PubMed Central

    Gearhart, John P.

    2006-01-01

    BACKGROUND Cloacal exstrophy is a rare, complex defect of the entire pelvis and its contents that occurs during embryogenesis and is associated with severe phallic inadequacy or phallic absence in genetic males. For about 25 years, neonatal assignment to female sex has been advocated for affected males to overcome the issue of phallic inadequacy, but data on outcome remain sparse. METHODS We assessed all 16 genetic males in our cloacal-exstrophy clinic at the ages of 5 to 16 years. Fourteen underwent neonatal assignment to female sex socially, legally, and surgically; the parents of the remaining two refused to do so. Detailed questionnaires extensively evaluated the development of sexual role and identity, as defined by the subjects' persistent declarations of their sex. RESULTS Eight of the 14 subjects assigned to female sex declared themselves male during the course of this study, whereas the 2 raised as males remained male. Subjects could be grouped according to their stated sexual identity. Five subjects were living as females; three were living with unclear sexual identity, although two of the three had declared themselves male; and eight were living as males, six of whom had reassigned themselves to male sex. All 16 subjects had moderate-to-marked interests and attitudes that were considered typical of males. Follow-up ranged from 34 to 98 months. CONCLUSIONS Routine neonatal assignment of genetic males to female sex because of severe phallic inadequacy can result in unpredictable sexual identification. Clinical interventions in such children should be reexamined in the light of these findings. PMID:14736925

  1. Sex ratio and spatial distribution of male and female Antennaria dioica (Asteraceae) plants

    NASA Astrophysics Data System (ADS)

    Varga, Sandra; Kytöviita, Minna-Maarit

    2011-09-01

    Sex ratio, sex spatial distribution and sexual dimorphism in reproduction and arbuscular mycorrhizal colonisation were investigated in the dioecious clonal plant Antennaria dioica (Asteraceae). Plants were monitored for five consecutive years in six study plots in Oulanka, northern Finland. Sex ratio, spatial distribution of sexes, flowering frequency, number of floral shoots and the number and weight of inflorescences were recorded. In addition, intensity of mycorrhizal fungi in the roots was assessed. Both sexes flowered each year with a similar frequency, but the overall genet sex ratio was strongly female-biased. The bivariate Ripley's analysis of the sex distribution showed that within most plots sexes were randomly distributed except for one plot. Sexual dimorphism was expressed as larger floral and inflorescence production and heavier inflorescences in males. In addition, the roots of both sexes were colonised to a similar extent by arbuscular mycorrhizal fungi. The female sex-biased flowering ratios reported are not consistent among years and cannot be explained in terms of spatial segregation of the sexes or sex lability. The possible reasons for the female-biased sex ratio are discussed.

  2. Determinants of Safer Sex Patterns among Gay/Bisexual Male Adolescents.

    ERIC Educational Resources Information Center

    Rotherram-Borus, Mary Jane; And Others

    1995-01-01

    Examined cognitive-behavioral (health-belief, social cognitive, peer support), risk-taking, and stress/coping models as predictors of safer sex practices among 136 gay/bisexual males, ages 14-19. Components of the health-belief, self-efficacy theories, and emotional distress models corresponded with safer sex practices; peer support was not…

  3. HIV Risk and Social Networks Among Male-to-Female Transgender Sex Workers in Boston, Massachusetts

    PubMed Central

    Reisner, Sari L.; Mimiaga, Matthew J.; Bland, Sean; Mayer, Kenneth H.; Perkovich, Brandon; Safren, Steven A.

    2013-01-01

    Male-to-female transgender individuals who engage in sex work constitute a group at high risk for HIV infection in the United States. This mixed-methods formative study examined sexual risk among preoperative transgender male-to-female sex workers (N = 11) in Boston. More than one third of the participants were HIV-infected and reported a history of sexually transmitted diseases. Participants had a mean of 36 (SD = 72) transactional male sex partners in the past 12 months, and a majority reported at least one episode of unprotected anal sex. Qualitative themes included (a) sexual risk, (b) motivations for engaging in sex work, (c) consequences of sex work, (d) social networks (i.e., trans mothers, who played a pivotal role in initiation into sex work), and (e) potential intervention strategies. Results suggest that interventions with transgender male-to-female sex workers must be at multiple levels and address the psychosocial and environmental contexts in which sexual risk behavior occurs. PMID:19732696

  4. The Sicker Sex: Understanding Male Biases in Parasitic Infection, Resource Allocation and Fitness

    PubMed Central

    Crdoba-Aguilar, Alex; Mungua-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

  5. Women's motivations to have sex in casual and committed relationships with male and female partners.

    PubMed

    Armstrong, Heather L; Reissing, Elke D

    2015-05-01

    Women report a wide variety of reasons to have sex (e.g., Meston & Buss, 2010), and while it is reasonable to assume that those reasons may vary based on the context of the relationship, this assumption has not yet been tested. The purpose of this study was to explore how relationship type, sexual attraction, and the gender of one's partner interact and affect the sexual motivations of women. A total of 510 women (361 who reported exclusively other-sex attraction and 149 who reported same-sex/bisexual attraction) completed the YSEX? questionnaire. Participants rated their sexual motivations for casual sex and sex in a committed relationship with male and/or female partners, depending on reported sexual attraction. Results showed that relationship type affected reported motivation for sex: physical motivations were more strongly endorsed for casual sex, whereas emotional motivations were more strongly endorsed for sex in committed relationships. No significant differences in motivation were reported between women who reported same-sex attraction and those who did not. Women who reported bisexual attraction and identified as being lesbian, bisexual, or another sexual minority reported no significant differences in motivation for sex with male or female partners. The results of this study highlight the importance of relationship context when discussing sexual motivation and suggest a high degree of similarity in motivation for women, regardless of sexual orientation or gender of partner. PMID:25567073

  6. 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

  7. 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

  8. 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

  9. Male Adolescent Birth Control Behavior: The Importance of Developmental Factors and Sex Differences.

    ERIC Educational Resources Information Center

    Cohen, Donald D.; Rose, Ryda D.

    1984-01-01

    A survey of sex and birth control behavior of 51 male adolescents aged 15-17 was conducted using structured interviews. Based on research with teenage females, three social influences were examined for their possible impact on male birth control behavior. (Author/BW)

  10. An oral male courtship pheromone terminates the response of Nasonia vitripennis females to the male-produced sex attractant.

    PubMed

    Ruther, Joachim; Hammerl, Theresa

    2014-01-01

    Sex pheromones are crucial for mate finding in many animals. Long-range attraction, mate recognition, and the elicitation of sexual receptiveness during courtship are typically mediated by different compounds. It is widely unknown, however, how the different components of a species' pheromone system influence each other. Here, we demonstrated in the parasitoid wasp Nasonia vitripennis that females quickly cease to respond to the male sex attractant after they contact a male's oral secretion during courtship. We used this behavioral switch to monitor the fractionation of head extracts from male wasps for identification of the bioactive compounds as a blend of ethyl oleate, ethyl linoleate, and ethyl ?-linolenate. This is the first identification of a cephalic courtship pheromone in parasitic Hymenoptera. Plasticity in pheromone-mediated sexual behavior of female insects has hitherto been attributed to the transfer of bioactive proteinaceous molecules with the male ejaculate. The pheromone interaction reported here sheds new light on the sexual communication of insects by showing that the sex pheromone response of females can be terminated by males independent of sperm transfer. PMID:24369389

  11. 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 Becks Depression Inventory and Zungs 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

  12. 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. Yim, Hye K.; Jung, Young S.; Park, Jae H.; Kim, Sung Y.

    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.

  13. 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

  14. Female Choice or Male Sex Drive? The Advantages of Male Body Size during Mating in Drosophila Melanogaster

    PubMed Central

    Jagadeeshan, Santosh; Shah, Ushma; Chakrabarti, Debarti; Singh, Rama S.

    2015-01-01

    The mating success of larger male Drosophila melanogaster in the laboratory and the wild has been traditionally been explained by female choice, even though the reasons are generally hard to reconcile. Female choice can explain this success by virtue of females taking less time to mate with preferred males, but so can the more aggressive or persistent courtships efforts of large males. Since mating is a negotiation between the two sexes, the behaviors of both are likely to interact and influence mating outcomes. Using a series of assays, we explored these negotiations by testing for the relative influence of male behaviors and its effect on influencing female courtship arousal threshold, which is the time taken for females to accept copulation. Our results show that large males indeed have higher copulation success compared to smaller males. Competition between two males or an increasing number of males had no influence on female sexual arousal threshold;—females therefore may have a relatively fixed ‘arousal threshold’ that must be reached before they are ready to mate, and larger males appear to be able to manipulate this threshold sooner. On the other hand, the females’ physiological and behavioral state drastically influences mating; once females have crossed the courtship arousal threshold they take less time to mate and mate indiscriminately with large and small males. Mating quicker with larger males may be misconstrued to be due to female choice; our results suggest that the mating advantage of larger males may be more a result of heightened male activity and relatively less of female choice. Body size per se may not be a trait under selection by female choice, but size likely amplifies male activity and signal outputs in courtship, allowing them to influence female arousal threshold faster. PMID:26658421

  15. Japan's progressive sex: male homosexuality, national competition, and the cinema.

    PubMed

    Hall, J M

    2000-01-01

    This essay serves as a broad investigation of the origins of what came to be called the "gay boom" in 1990's Japanese cinema: a culmination of print media, television, and especially films which made the gay male not merely a visible (political) subject but also the site of displaced contestations of gendered (female) desire. The most visible transnational signifier of the "gay boom" was the 1992 film Okoge, a film which, in keeping with a Japanese trend which relocates the gay male as a safe displacement of female desire, posits the heterosexual female as the audience's point of identification in a film about the lives of gay Japanese men. Using this as a starting point, this essay seeks to explore how male homosexuality and gender construction operate within both Japanese nationalism and the transnational discourse of Japanese cinema's dissemination. PMID:11133140

  16. 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

  17. Pregnancy rate of Nelore females inseminated with male-sexed semen.

    PubMed

    Dominguez, José Henrique E; Costa, Deiler S; Centurion, Victor Jojot; Faria, Fabio José C

    2011-12-01

    Pregnancy rates of Nelore females inseminated with male-sexed semen and conventional semen from the same bulls were evaluated. The females included 433 heifers (2 years old) and 230 non-suckling cows, totaling 663 animals. Average body condition score was 3.5 (1-5 scale). Estrus was induced with prostaglandin F2α. The total pregnancy rate of females inseminated with male-sexed semen of bulls A, B and C was 38.8% (131/338) less (P<0.0001) than the total pregnancy rate observed for females inseminated with conventional semen from the same bulls (57.9% [188/325]). Pregnancy rates of non-suckling cows inseminated with male-sexed semen was 43.3% (49/113), which was similar (P≥0.05) to the values found for heifers inseminated with male-sexed semen from the same bulls (36.4% [82/225]). The pregnancy rate of females inseminated with male-sexed semen was less compared with females inseminated with conventional semen. In addition, there was no significant difference in the pregnancy rate of heifers versus non-suckling cows. PMID:22154476

  18. METHODS OF PROMOTING SAFER SEX BEHAVIORS UTILIZED BY MEN WHO HAVE SEX WITH MALE CASUAL SEX PARTNERS

    PubMed Central

    Serovich, Julianne M.; Craft, Shonda M.; McDowell, Tiffany L.; Grafsky, Erika L.; Andrist, David

    2009-01-01

    The purpose of this article is to report results of a qualitative investigation into the methods that HIV-positive men who have sex with men (MSM) use to initiate safer sex with casual sexual partners. In-depth, qualitative interviews were conducted with 57 HIV-positive adult MSM living in a large midwestern city. Using an inductive approach to data analysis, participants revealed a typology of safer sex strategies that can be placed into four primary categorizations: having a nonnegotiable sexual behavior policy, behaviorally controlling the interaction, being verbally direct, and being verbally indirect. Strategies varied by degree of explicitness and partner involvement. Men in this study often employed multiple strategies if their partner was not initially receptive to engaging in safer sex behaviors. The strategies described can be especially beneficial to those working in the area of HIV prevention. Providing MSM a variety of options to initiate safer sex may enhance current prevention efforts. PMID:19243227

  19. Dysregulation of male sex hormones in chronic hepatitis C patients.

    PubMed

    El-Serafi, A T; Osama, S; El-Zalat, H; El-Deen, I M

    2016-02-01

    Chronic hepatitis C (HCV) infection is a serious problem all over the world and has a special importance in Egypt, where the prevalence of infection is 14.7% of population. In males, HCV is associated with sexual dysfunction and changes in the semen parameters. This study aimed at estimation of a panel of the most important related hormones in the serum of patients and illustration of their correlation to the routine laboratory investigations. The four studied hormones showed alteration in the patients in comparison with the controls. While androstenedione, prolactin and testosterone were significantly increased in patients, dehydroepiandrosterone sulphate was decreased. These changes in the hormones were not related to the liver functions, pathological grade or even viral load. We hypothesised a model of how HCV can induce these hormonal changes and recommended to add these hormones to the follow-up panel of male patients with HCV. PMID:25912488

  20. 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

  1. Clover root exudate produces male-biased sex ratios and accelerates male metamorphic timing in wood frogs

    PubMed Central

    Lambert, Max R.

    2015-01-01

    In amphibians, abnormal metamorph sex ratios and sexual development have almost exclusively been considered in response to synthetic compounds like pesticides or pharmaceuticals. However, endocrine-active plant chemicals (i.e. phytoestrogens) are commonly found in agricultural and urban waterways hosting frog populations with deviant sexual development. Yet the effects of these compounds on amphibian development remain predominantly unexplored. Legumes, like clover, are common in agricultural fields and urban yards and exude phytoestrogen mixtures from their roots. These root exudates serve important ecological functions and may also be a source of phytoestrogens in waterways. I show that clover root exudate produces male-biased sex ratios and accelerates male metamorphosis relative to females in low and intermediate doses of root exudate. My results indicate that root exudates are a potential source of contaminants impacting vertebrate development and that humans may be cultivating sexual abnormalities in wildlife by actively managing certain plant species.

  2. Clover root exudate produces male-biased sex ratios and accelerates male metamorphic timing in wood frogs.

    PubMed

    Lambert, Max R

    2015-12-01

    In amphibians, abnormal metamorph sex ratios and sexual development have almost exclusively been considered in response to synthetic compounds like pesticides or pharmaceuticals. However, endocrine-active plant chemicals (i.e. phytoestrogens) are commonly found in agricultural and urban waterways hosting frog populations with deviant sexual development. Yet the effects of these compounds on amphibian development remain predominantly unexplored. Legumes, like clover, are common in agricultural fields and urban yards and exude phytoestrogen mixtures from their roots. These root exudates serve important ecological functions and may also be a source of phytoestrogens in waterways. I show that clover root exudate produces male-biased sex ratios and accelerates male metamorphosis relative to females in low and intermediate doses of root exudate. My results indicate that root exudates are a potential source of contaminants impacting vertebrate development and that humans may be cultivating sexual abnormalities in wildlife by actively managing certain plant species. PMID:27019728

  3. Greater memory impairment in dementing females than males relative to sex-matched healthy controls.

    PubMed

    Gale, Shawn D; Baxter, Leslie; Thompson, Juliann

    2016-06-01

    Previously we demonstrated sex differences in episodic memory in healthy elderly and suggested that normative data be separated by sex. The present study extended the exploration of sex differences on memory measures into two clinical populations, mild cognitive impairment (MCI) and Alzheimer's disease (AD). Seventy-six subjects with MCI and 101 subjects with AD diagnosed by a multidisciplinary team were included. These two groups were also compared to a group of 177 healthy elderly control participants. Sex differences on the Rey Auditory Verbal Learning Test (RAVLT; total and delayed recall) raw scores and Brief Visuospatial Memory Test-Revised (BVMT-R) were demonstrated within the healthy but not the MCI or AD groups. Calculating z scores by sex for both dementing groups based on the healthy controls suggested a larger performance gap between healthy and dementing women than between healthy and dementing men. MCI females were on average 0.48 standard deviations lower for total verbal learning compared to healthy female controls than were MCI males when compared to healthy male controls. For verbal delayed recall the gap was even larger (SD = 1.09). Similarly, on the BVMT-R, a measure of visual memory, the difference was 0.60 standard deviations for total visual learning and 0.99 standard deviations for delayed recall. This same sex difference, with females showing greater impairment compared to the controls group than did the males, was also present within the AD group. The greater memory impairment in dementing females rather than males when compared to sex-matched healthy controls was unlikely to be due to more severe illness since females performed equivalently to males on the Clinical Dementia Rating Scale, Mini-Mental Status Examination, and Dementia Rating Scale, and were also similar for age, education, and apolipoprotein status. The present study suggested relatively greater memory impairment in females with MCI or AD than in controls. PMID:26735615

  4. Low concentrations of dihydrotestosterone induce female-to-male sex reversal in the frog Pelophylax nigromaculatus.

    PubMed

    Xu, Wei; Li, Yuan-Yuan; Lou, Qin-Qin; Chen, Xiao-Ran; Qin, Zhan-Fen; Wie, Wu-Ji

    2015-10-01

    Previous studies have demonstrated that some amphibian species can be sex-reversed by high concentrations of androgens. Little attention has focused on the effects of androgenic endocrine-disrupting chemicals (EDCs) on amphibians. The present study aimed to investigate the effects of lower concentrations of the androgenic EDC 5?-dihydrotestosterone (DHT) on gonadal differentiation and development in Pelophylax nigromaculatus, a true frog distributed widely in East Asia. Tadpoles at Gosner stage 24/25 were exposed to nominal concentrations of 40 ng/L, 400 ng/L, and 4000 ng/L DHT to complete metamorphosis. In all DHT treatment groups, males and ambiguous sexes were identified based on gonadal morphology, whereas no females were found; thus, all treatment groups exhibited male-skewed ratios compared with the control group. Gonadal histological examination revealed that ambiguous sexes displayed overall testicular structure with certain ovarian characteristics, demonstrating that DHT-induced sex-ambiguous gonads were incomplete ovary-to-testis reversals (IOTTRs). The expression levels of some ovary-biased genes in the IOTTRs were significantly higher than in the control testes but lower than in the control ovaries. These results show that low concentrations of DHT induced complete or incomplete female-to-male sex reversal in P. nigromaculatus, and incomplete sex reversal retained certain ovarian characteristics not only at gonadal morphological and histological levels but also at the molecular level. They present study highlights potential risks of DHT and other androgenic EDCs for P. nigromaculatus. PMID:26226837

  5. 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

  6. 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

  7. Comparative study of the reproductive characteristics of XY male and hormonally sex-reversed XX male Eurasian perch, Perca fluviatilis.

    PubMed

    Rougeot, Carole; Nicayenzi, Flix; Mandiki, S N M; Rurangwa, Eugne; Kestemont, Patrick; Mlard, Charles

    2004-09-01

    In order to compare the reproductive capacity of XY male versus XX male (neomales) Eurasian perch (Perca fluviatilis), we determined the sperm quality (sperm concentration and motility) and reproductive characteristics such as gonadosomatic index (GSI), fertilization rate and sex steroid levels (testosterone, T; 17beta-estradiol, E2 and 11-ketotestosterone, 11KT) during the reproductive season. Median GSI was not significantly different between XY males (7.9%) and XX males (7.5%). Fertilization rates ranged between 30.0 and 98.0%. Sperm concentration ranged between 27.9 x 10(9) and 42.0 x 10(9) spermatozoa ml(-1). Median level of T, 11KT and E2 levels increased in the middle of the reproductive season (2136.0, 2409.0 and 3252.0 pg ml(-1), respectively) and decreased at the end (1657.0, 2006.6 and 431.0 pg ml(-1), respectively). Sperm motility was assessed by CASA and expressed by the curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), percentage of motile sperm (% MOT) and motile concentration (MOC). Overall, there were not any significant differences between XY and XX males. In conclusion, no differences of reproductive capacities were observed between XY males and XX males suggesting that the last can be crossed with females to improve the productivity of Eurasian perch by producing all-female stock. PMID:15251230

  8. A cause for concern: male couples' sexual agreements and their use of substances with sex.

    PubMed

    Mitchell, Jason W; Boyd, Carol; McCabe, Sean; Stephenson, Rob

    2014-07-01

    Substance use is strongly associated with HIV risk among gay men. Many gay couples establish sexual agreements. However, little is known about gay couples' use of substances with sex, and whether substance use is associated with couples' agreements. The present study assessed whether gay couples' use of substances with sex was associated with their establishment of, type of, and adherence to, a sexual agreement. Dyadic data from 275 HIV-negative US gay couples were collected online in a nation-wide, cross-sectional study, and analyzed at the couple-level. Findings revealed that couples with an established agreement, and a recently broken agreement, were more likely to have used amyl nitrates and marijuana with sex within their relationship. This same trend was also noted, but for alcohol use with sex outside of couples' relationships. Further research is urgently needed to examine the fluidity of HIV-negative gay male couples' sexual agreements and substance use with sex. PMID:24584415

  9. The trap of sex in social insects: from the female to the male perspective.

    PubMed

    Beani, Laura; Dessì-Fulgheri, Francesco; Cappa, Federico; Toth, Amy

    2014-10-01

    The phenotype of male Hymenoptera and the peculiar role of males has been neglected and greatly understudied, given the spectacular cooperative behavior of female social insects. In social insects there has been considerable progress in understanding the molecular mechanisms behind haplodiploid sex determination but, beyond that, very little is known concerning the neural, endocrine, and genetic correlates of sexual selection in males. An opportunity is being missed: the male phenotype in Hymenoptera is a natural experiment to compare the drives of natural versus sexual selection. In contrast to females, males do not work, they usually display far from the nest to gain mates, compete among rivals in nuptial flights or for a symbolic territory at leks, and engage in direct or ritualized conflicts. By comparing the available data on male paper wasps with studies on other social Hymenoptera, we summarize what we currently know about the physical, hormonal, neural and behavioral traits in a model system appropriate to examine current paradigms on sexual selection. Here we review male behavior in social Hymenoptera beyond sex stereotypes: the subtle role of "drones" in the colony, the lack of armaments and ornaments, the explosive mating crowds, the "endurance" race, the cognitive bases of the "choosy" male and his immune defense. Social insect males are not just simple-minded mating machines, they are shaped, constrained and perhaps trapped by sexual selection. PMID:25280909

  10. Male gonadal function in coeliac disease: 2. Sex hormones.

    PubMed Central

    Farthing, M J; Rees, L H; Edwards, C R; Dawson, A M

    1983-01-01

    Hypogonadism, infertility, and sexual dysfunction occur in some men with coeliac disease. We have measured plasma testosterone, dihydrotestosterone, sex-hormone binding globulin, oestradiol, and serum luteinising hormone in 41 men with coeliac disease and have related these findings to jejunal morphology, fertility, semen quality, and sexual function. To determine the specificity of these observations in coeliacs we also studied 19 nutritionally-matched men with Crohn's disease, and men with chronic ill-health due to rheumatoid arthritis and Hodgkin's disease. The most striking endocrine findings in untreated coeliacs were increased plasma testosterone and free testosterone index, reduced dihydrotestosterone (testosterone's potent peripheral metabolite), and raised serum luteinising hormone, a pattern of abnormalities indicative of androgen resistance. As jejunal morphology improved hormone levels appeared to return to normal. This specific combination of abnormalities was not present in any of the disease control groups and, to our knowledge, androgen resistance has not been described previously in any other non-endocrine disorder. Plasma oestradiol concentration was modestly raised in 10% of coeliacs and 11% of patients with Crohn's disease. Unlike plasma androgens and serum luteinising hormone in coeliacs, plasma oestradiol was not clearly related to jejunal morphology. Androgen resistance and associated hypothalamic-pituitary dysfunction appear to be relatively specific to coeliac disease and cannot be explained merely in terms of malnutrition or chronic ill-health. In addition, our findings suggest that this endocrine disturbance may be related to sexual dysfunction in coeliac disease but its relationship to disordered spermatogenesis in this condition has not been clearly established. PMID:6682819

  11. Male-Sex-Ratio Trait in Drosophila Pseudoobscura: Frequency of Autosomal Aneuploid Sperm

    PubMed Central

    Cobbs, G.; Jewell, L.; Gordon, L.

    1991-01-01

    Males with the SR X chromosome show the ``sex-ratio'' (sr) phenotype in which they produce almost entirely daughters. The few sons (about 1%) are invariably sterile X/O males and result entirely from nullo-XY sperm. The ``male-sex-ratio'' (msr) phenotype is a modified form of sr in which SR/Y males produce a higher frequency of sterile X/O sons. The msr trait is due to the presence of the SR X-chromosome in males which are also homozygous for one or more autosomes from the L116 strain. Here the frequency of nullo-3 and diplo-3 sperm from msr males was measured by crossing to a compound-3 strain and found to be 13.8% and 3.2%, respectively, of the total viable sperm. The sr males produced very low levels of nullo-3 sperm at a frequency not different from control X/Y males and a slightly elevated frequency of diplo-3 sperm over X/Y males. The msr males were found to have only 12% the fecundity of sr males and in matings to cause a high frequency of brown inviable eggs. These results indicate that high rates of autosomal aneuploidy are not restricted to chromosome 3 but also occur for chromosomes 2, 4 and 5. The overall frequency of autosomal aneuploid sperm is estimated to be approximately 50%. Microscopic studies of meiosis in testes from msr males indicates meiotic nondisjunction and meiotic chromosome loss are responsible for the msr phenotype. Last, microscopic studies of sperm cysts from msr males reveal high levels of spermiogenic failure. PMID:2004709

  12. Strategies for recruiting steady male partners of female sex workers for HIV research

    PubMed Central

    Fleming, Paul J.; Barrington, Clare; Perez, Martha; Donastorg, Yeycy; Kerrigan, Deanna

    2014-01-01

    Steady male partners of female sex workers (FSW) are a key population for HIV prevention, but researchers face challenges finding and recruiting this population. We conducted forty in-depth interviews with FSW and steady male partners of FSW in Santo Domingo, Dominican Republic about how to engage steady male partners in HIV research. Participants cautioned that male partners might be unwilling to participate because of discomfort disclosing intimate information and cultural norms of masculinity. They recommended inviting male partners to research offices, instead of venue-based recruitment, because it was more private and trust-promoting. Most participants suggested that FSW could refer their partners or men could refer their friends who have FSW partners. Participants emphasized that referrals could break down trust-related barriers that prevent male partners from participating. Establishing an environment of respect and trust in the research setting can aid referral processes as individuals who participate communicate their positive experiences to their networks. PMID:25192901

  13. Strategies for recruiting steady male partners of female sex workers for HIV research.

    PubMed

    Fleming, Paul J; Barrington, Clare; Perez, Martha; Donastorg, Yeycy; Kerrigan, Deanna

    2015-02-01

    Steady male partners of female sex workers (FSW) are a key population for HIV prevention, but researchers face challenges finding and recruiting this population. We conducted 40 in-depth interviews with FSW and steady male partners of FSW in Santo Domingo, Dominican Republic about how to engage steady male partners in HIV research. Participants cautioned that male partners might be unwilling to participate because of discomfort disclosing intimate information and cultural norms of masculinity. They recommended inviting male partners to research offices, instead of venue-based recruitment, because it was more private and trust-promoting. Most participants suggested that FSW could refer their partners or men could refer their friends who have FSW partners. Participants emphasized that referrals could break down trust-related barriers that prevent male partners from participating. Establishing an environment of respect and trust in the research setting can aid referral processes as individuals who participate communicate their positive experiences to their networks. PMID:25192901

  14. 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

  15. Male Sex Workers: Practices, Contexts, and Vulnerabilities for HIV acquisition and transmission

    PubMed Central

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

    2015-01-01

    Summary Male sex workers (MSW) who sell/exchange sex for money or goods comprise an extremely diverse population across and within countries worldwide. Information characterizing their practices, contexts where they live, and their needs is very limited, as these men are generally included as subsets of larger studies focused on gay men and other men who have sex with men (MSM) or even female sex workers. MSW, regardless of their sexual orientation, mostly offer sex to men, and rarely identify as sex workers, using local or international terms instead. There is growing evidence of a sustained or increasing burden of HIV among some MSW in the context of the slowing global HIV pandemic. There are several synergistic facilitator spotentiating HIV acquisition and transmission among MSW, including biological, behavioural, and structural determinants. The criminalization and intersectional stigmas of same-sex practices, commercial sex, and HIV all increase HIV and STI risk for MSW and decrease their likelihood of accessing essential services. These contexts, taken together with complex sexual networks among MSW, define them 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. PMID:25059939

  16. The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size

    PubMed Central

    Rideout, Elizabeth J.; Narsaiya, Marcus S.; Grewal, Savraj S.

    2015-01-01

    Almost all animals show sex differences in body size. For example, in Drosophila, females are larger than males. Although Drosophila is widely used as a model to study growth, the mechanisms underlying this male-female difference in size remain unclear. Here, we describe a novel role for the sex determination gene transformer (tra) in promoting female body growth. Normally, Tra is expressed only in females. We find that loss of Tra in female larvae decreases body size, while ectopic Tra expression in males increases body size. Although we find that Tra exerts autonomous effects on cell size, we also discovered that Tra expression in the fat body augments female body size in a non cell-autonomous manner. These effects of Tra do not require its only known targets doublesex and fruitless. Instead, Tra expression in the female fat body promotes growth by stimulating the secretion of insulin-like peptides from insulin producing cells in the brain. Our data suggest a model of sex-specific growth in which body size is regulated by a previously unrecognized branch of the sex determination pathway, and identify Tra as a novel link between sex and the conserved insulin signaling pathway. PMID:26710087

  17. The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size.

    PubMed

    Rideout, Elizabeth J; Narsaiya, Marcus S; Grewal, Savraj S

    2015-12-01

    Almost all animals show sex differences in body size. For example, in Drosophila, females are larger than males. Although Drosophila is widely used as a model to study growth, the mechanisms underlying this male-female difference in size remain unclear. Here, we describe a novel role for the sex determination gene transformer (tra) in promoting female body growth. Normally, Tra is expressed only in females. We find that loss of Tra in female larvae decreases body size, while ectopic Tra expression in males increases body size. Although we find that Tra exerts autonomous effects on cell size, we also discovered that Tra expression in the fat body augments female body size in a non cell-autonomous manner. These effects of Tra do not require its only known targets doublesex and fruitless. Instead, Tra expression in the female fat body promotes growth by stimulating the secretion of insulin-like peptides from insulin producing cells in the brain. Our data suggest a model of sex-specific growth in which body size is regulated by a previously unrecognized branch of the sex determination pathway, and identify Tra as a novel link between sex and the conserved insulin signaling pathway. PMID:26710087

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

    NASA Astrophysics Data System (ADS)

    Szász, Eszter; Garamszegi, László Zsolt; Hegyi, Gergely; Szöllősi, 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.

  19. Male-specific suppression of hepatic microsomal UDP-glucuronosyl transferase activities toward sex hormones in the adult male rat administered bisphenol A.

    PubMed Central

    Shibata, Noriaki; Matsumoto, Junya; Nakada, Ken; Yuasa, Akira; Yokota, Hiroshi

    2002-01-01

    Various adverse effects of endocrine disruptors on the reproductive organs of male animals have been reported. We found that UDP-glucuronosyltransferase (UGT) activities towards bisphenol A, testosterone and oestradiol were significantly decreased in liver microsomes prepared from adult male Wistar rats administered with the endocrine disruptor bisphenol A (1 mg/2 days for 2 or 4 weeks). However, suppression of the transferase activities was not observed in female rats, even after bisphenol A treatment for 4 weeks. Diethylstilbestrol, which is well known as an endocrine disruptor, had the same effects, but p -cumylphenol had no effect on UGT activities towards sex hormones. Co-administration of an anti-oestrogen, tamoxifen, inhibited the suppression of the transferase activities by bisphenol A. Western blotting analysis showed that the amount of UGT2B1, an isoform of UGT which glucuronidates bisphenol A, was decreased in the rat liver microsomes by the treatment. Northern blotting analysis also indicated that UGT2B1 mRNA in the liver was decreased by bisphenol A treatment. The suppression of UGT activities, UGT2B1 protein and UGT2B1 mRNA expression did not occur in female rats. The results indicate that bisphenol A treatment reduces the mRNA expression of UGT2B1 and other UGT isoforms that mediate the glucuronidation of sex hormones in adult male rats, and this suggests that the endocrine balance may be disrupted by suppression of glucuronidation. PMID:12230427

  20. 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

  1. 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...

  2. Male Sex Roles and Epithets for Ethnic Women in American Slang.

    ERIC Educational Resources Information Center

    Allen, Irving Lewis

    1984-01-01

    Research shows that derogatory names used for women of ethnic outgroups (1) are aimed disproportionately at women of racial minorities; (2) stereotype physical differences between ethnic groups; (3) make derogatory sexual allusions, often using food and animal metaphors; and (4) display the strains of traditional male sex roles in ethnic and

  3. Identification of a Sex Attractant Pheromone for Male Winterform Pear Psylla, Cacopsylla pyricola

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pear psylla, Cacopsylla pyricola (Frster) (Hemiptera: Psyllidae), a major economic pest of pears, have been shown to use a female-produced sex attractant pheromone. We compared the chemical profiles obtained from cuticular extracts of diapausing and post-diapause winterform males and females, with...

  4. 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

  5. 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...

  6. Differences of Personality, Defensiveness, and Compliance between Admitting and Denying Male Sex Offenders.

    ERIC Educational Resources Information Center

    Birgisson, Gunnar Hrafn

    1996-01-01

    Assessed predicted psychological differences between denying (n=30) and admitting (n=72) male sex offenders within the framework of Eysenck's theory on the personality of criminals. The Eysenck Personality Questionnaire (EPQ) and Gudjonsson's Compliance Questionnaire (CQ) were administered to consenting participants who were probationers in…

  7. A novel approach to sexing bovine blastocysts using male-specific gene expression.

    PubMed

    Hamilton, C K; Combe, A; Caudle, J; Ashkar, F A; Macaulay, A D; Blondin, P; King, W A

    2012-05-01

    When examining gene expression profiles for the purposes of assessing embryo quality, it is imperative that sex be considered, because many embryonic transcripts have sex-related expression patterns. The objective of this study was to systematically examine eight Y chromosome linked genes (DDX3Y, EIF1AY, HSFY, SRY, TSPY, USP9Y, ZFY, and ZRSR2Y) to characterize their expression in bovine blastocysts and to examine the usefulness of this expression for the purpose of RNA-based embryo sexing. In order to examine the expression of these genes, pools of blastocysts (groups of 10 and 20) as well as single embryos (N = 50) were analyzed with reverse transcriptase polymerase chain reaction (RT-PCR) and reverse transcriptase quantitative PCR (RT-qPCR). Of the 50 single embryos, 32 were concurrently sexed with DNA-based methods. Transcripts of DDX3Y, EIF1AY, TSPY, USP9Y, ZFY and ZRSR2Y were detected in the pooled and single blastocysts, but no transcripts were detected for HSFY or SRY. After performing DNA-based sexing experiments, we concluded that this expression was restricted to the male embryos. The consistency of the expression varied according to the gene as well as the specific primer set. Three genes were expressed in the full set of male embryos, DDX3Y, USP9Y, and ZRSR2Y and therefore represent good candidates for RNA-based sexing methods. PMID:22341705

  8. 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

  9. 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

  10. 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

  11. 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

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

    PubMed Central

    Padilla, Mark; Castellanos, Daniel; Guilamo-Ramos, Vincent; Reyes, Armando Matiz; Snchez 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 mens sexual risk disclosure, and potentially elevated their own and their female partners vulnerability to HIV infection. Based on the studys 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

  13. Stigma in Male Depression and Suicide: A Canadian Sex Comparison Study.

    PubMed

    Oliffe, John L; Ogrodniczuk, John S; Gordon, Susan J; Creighton, Genevieve; Kelly, Mary T; Black, Nick; Mackenzie, Corey

    2016-04-01

    Stigma in men's depression and suicide can restrict help-seeking, reduce treatment compliance and deter individuals from confiding in friends and family. In this article we report sex comparison findings from a national survey of English-speaking adult Canadians about stigmatized beliefs concerning male depression and suicide. Among respondents without direct experience of depression or suicide (n = 541) more than a third endorsed the view that men with depression are unpredictable. Overall, a greater proportion of males endorsed stigmatizing views about male depression compared to female respondents. A greater proportion of female respondents endorsed items indicating that men who suicide are disconnected, lost and lonely. Male and female respondents with direct personal experience of depression or suicide (n = 360) strongly endorsed stigmatizing attitudes toward themselves and a greater proportion of male respondents indicated that they would be embarrassed about seeking help for depression. PMID:26733336

  14. Androgens regulate sex differences in signaling but are not associated with male variation in morphology in the weakly electric fish Parapteronotus hasemani.

    PubMed

    Petzold, Jacquelyn M; Smith, G Troy

    2016-02-01

    Sexually dimorphic signaling is widespread among animals and can act as an honest indicator of mate quality. Additionally, differences in signaling and morphology within a sex can be associated with different strategies for acquiring mates. Weakly electric fish communicate via self-generated electrical fields that transmit information about sex, reproductive state, and social status. The weakly electric knifefish Parapteronotus hasemani exhibits sexual dimorphism in body size as well as substantial within-male variation in body size and jaw length. We asked whether P. hasemani exhibits hormonally mediated sexual dimorphism in electrocommunication behavior. We also asked whether males with short versus long jaws differed significantly from each other in morphology, behavior, hormone levels, or reproductive maturity. Males produced longer chirps than females, but other signal parameters (electric organ discharge frequency; chirp rate and frequency modulation) were sexually monomorphic. Pharmacologically blocking androgen receptors in males reduced chirp duration, suggesting that this sexually dimorphic trait is regulated at least in part by the activational effects of androgens. Males sorted into two distinct morphological categories but did not differ in circulating 11-ketotestosterone or testosterone. Short-jawed males and long-jawed males also did not differ in any aspects of signaling. Thus, chirping and high levels of 11-ketotestosterone were reliably associated with reproductively active males but do not necessarily indicate male type or quality. This contrasts with other alternative male morph systems in which males that differ in morphology also differ in androgen profiles and signaling behavior. PMID:26518663

  15. Electrophysiological and behavioral responses of Diaphania glauculalis males to female sex pheromone.

    PubMed

    Ma, Tao; Liu, Zhi Tao; Zhang, Yuan Yuan; Sun, Zhao Hui; Li, Yi Zhen; Wen, Xiu Jun; Chen, Xiao Yang

    2015-10-01

    The aim of this study is to identify the pheromone active component of female moths, Diaphania glauculalis, an important pest of Anthocephalus chinensis in China. The sex pheromone was extracted from sex pheromone gland extracts of virgin female moth of D. glauculalis using n-hexane, and the pheromone gland extracts of females were analyzed using coupled gas chromatography-electroantennogram detection (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). The sex pheromone active components were based on the comparison the retention time and mass spectrum, with suitable synthetic compounds. (E)-11-hexadecenal (E11-16:Ald) and (E,E)-10,12-hexadecadienal (E10E12-16:Ald) were identified as the major sex pheromone components in the females. Their biological activities were evaluated in a series of electroantennogram (EAG) experiments and four-arm olfactometer assays using synthetic compounds. D. glauculalis males could be attracted by any single component, but a mixture of the E11-16:Ald and E10E12-16:Ald in a ratio of 5:5 elicited a substantial response, demonstrating that the binary blend is essential in male attraction. We therefore conclude that the aldehyde compounds, a mixture of E11-16:Ald and E10E12-16:Ald, comprise the sex pheromone components of D. glauculalis, which might be applied for insect field trapping. PMID:26002369

  16. Hombre Seguro (Safe Men): a sexual risk reduction intervention for male clients of female sex workers

    PubMed Central

    2014-01-01

    Background Male clients of female sex workers (FSWs) are at risk of HIV and other sexually transmitted infections (STIs). We conducted a two-arm randomized controlled trial to test the efficacy of a sexual risk reduction intervention for male clients of FSWs in Tijuana, Mexico. Methods/Design Male clients of FSWs who were at least 18, were HIV-negative at baseline, and reported recent unprotected sex with FSWs were randomized to the Hombre Seguro sexual risk reduction intervention, or a time-attention didactic control condition. Each condition lasted approximately one hour. Participants underwent interviewer-administered surveys and testing for HIV and other STIs at baseline, and at 4, 8, and 12 month follow-ups. Combined HIV/STI incidence and unprotected vaginal and anal sex acts with FSWs were the primary outcomes. Discussion A total of 400 participants were randomized to one of the two conditions. Analyses indicated that randomization was successful; there were no significant differences between the participants in the two conditions at baseline. Average follow-up was 84% across both conditions. This is the first study to test the efficacy of a sexual risk reduction intervention for male clients of FSWs using the rigor of a randomized controlled trial. Trial registration NCT01280838, Date of registration: January 19, 2011. PMID:24885949

  17. Experience-independent sex differences in newborn macaques: Females are more social than males.

    PubMed

    Simpson, Elizabeth A; Nicolini, Ylenia; Shetler, Melissa; Suomi, Stephen J; Ferrari, Pier F; Paukner, Annika

    2016-01-01

    Human females exhibit greater social interest and skills relative to males, appearing in infancy, suggesting biological roots; however, male and female infants may be treated differently, potentially causing or amplifying sex differences. Here, we tested whether sex differences in social motivation emerge in infant monkeys (n?=?48) reared in a controlled postnatal environment. Compared to males, females at 2-3 weeks looked more at conspecifics' faces (d?=?0.65), especially the eyes (d?=?1.09), and at 4-5 weeks exhibited more affiliative behaviors (d?=?0.64), including gesturing, looking, and proximity to familiar and unfamiliar human caretakers. In sum, converging evidence from humans and monkeys suggests that female infants are more social than males in the first weeks of life, and that such differences may arise independent of postnatal experience. Individual differences in social interest have wide-ranging developmental consequences, impacting infants' social interaction quality and opportunities for learning. Understanding the evolution of sex differences and their developmental emergence is necessary to best support infants with varying levels of sociality. PMID:26794858

  18. Experience-independent sex differences in newborn macaques: Females are more social than males

    PubMed Central

    Simpson, Elizabeth A.; Nicolini, Ylenia; Shetler, Melissa; Suomi, Stephen J.; Ferrari, Pier F.; Paukner, Annika

    2016-01-01

    Human females exhibit greater social interest and skills relative to males, appearing in infancy, suggesting biological roots; however, male and female infants may be treated differently, potentially causing or amplifying sex differences. Here, we tested whether sex differences in social motivation emerge in infant monkeys (n = 48) reared in a controlled postnatal environment. Compared to males, females at 2–3 weeks looked more at conspecifics’ faces (d = 0.65), especially the eyes (d = 1.09), and at 4–5 weeks exhibited more affiliative behaviors (d = 0.64), including gesturing, looking, and proximity to familiar and unfamiliar human caretakers. In sum, converging evidence from humans and monkeys suggests that female infants are more social than males in the first weeks of life, and that such differences may arise independent of postnatal experience. Individual differences in social interest have wide-ranging developmental consequences, impacting infants’ social interaction quality and opportunities for learning. Understanding the evolution of sex differences and their developmental emergence is necessary to best support infants with varying levels of sociality. PMID:26794858

  19. Risk factors for HIV and syphilis infection among male sex workers who have sex with men: a cross-sectional study in Hangzhou, China, 2011

    PubMed Central

    Luo, Yan; Zhu, Chunyan; Chen, Shuchang; Geng, Qingshan; Fu, Rong; Li, Xiting; Xu, Ke; Cheng, Jie; Ding, Jianming

    2015-01-01

    Objective To investigate the prevalence and risk factors of HIV and syphilis infection among men who have sex with men (MSM) in male sex workers (MSW). Design Cross-sectional survey. Setting Hangzhou, China. Participants 259 MSW in MSM were recruited by respondent-driven sampling from May 2011 to December 2011.The inclusion criteria were: (1) age ≥18 years; (2) engaging in sex with men in the previous year and (3) willing to cooperate in the implementation of the study. Outcome measures HIV-related knowledge, high-risk behaviour and condom use. Results Among these MSW in MSM, 23.2% were infected with HIV and/or syphilis, 8.9% were infected only with HIV, 12.7% only with syphilis and 1.5% with HIV/syphilis co-infection; 96.6% sold sex to males, 8.9% bought sex from males and 15.4% sold sex to females; 49.0% had non-commercial sex behaviours with males and 24.3% with females. The rate of condom use while having commercial sex with clients was 86.9% and 53.3% (selling anal and oral sex to males, respectively), 95.5% (buying sex from males) and 77.5% (selling sex to females), respectively. Regarding their non-commercial sex behaviour, the rate of condom use was 77.2% (with males) and 49.2% (with females), respectively. Multivariate analysis showed that age >30 years (OR 1.055; 95% CIs 1.015 to 1.095) and having ≥10 non-commercial male sex partners (OR, 1.573; 95% CI 1.018 to 2.452) were significantly associated with HIV/syphilis infection, while heterosexuality (OR, 0.238; 95% CI 0.066 to 0.855) was significantly associated with a low HIV/syphilis infection rate. Conclusions The MSW in MSM population in Hangzhou has a high prevalence of HIV/syphilis infection, poor perceived risks of HIV and more engagement in unsafe sex with its clients and partners, in addition to a low rate of condom use. These risk factors may account for their relatively high infection rate of HIV/syphilis. PMID:25922096

  20. An Exploratory Study of HIV Risk Behaviors and Testing among Male Sex Workers in Beirut, Lebanon.

    PubMed

    Aunon, Frances M; Wagner, Glenn J; Maher, Rabih; Khouri, Danielle; Kaplan, Rachel L; Mokhbat, Jacques

    2015-01-01

    Male sex workers (MSW) are a particularly high-risk subset of men who have sex with men in Lebanon and report higher numbers of sex partners and lower rates of condom use. The purpose was to explore the factors influencing sexual risk behaviors and HIV testing among MSW. Qualitative interviews were conducted with 16 MSW living in Beirut and working in bathhouses (hammam) or as escorts; content analysis identified emergent themes. Escorts reported more consistent condom use with clients and HIV testing than hammam MSW, with influential factors including HIV risk knowledge and perceived risk susceptibility, job security, and internalized stigma and related feelings of self-worth and fatalism regarding health and HIV risk. In contrast, both groups of MSW typically opted not to condoms with nonclient sex partners, in an effort to differentiate sex for work versus pleasure. The uptake of HIV testing was limited by concerns about the confidentiality of the test results and fear of repercussions of a positive test result for their health and employment. The respondents described an insular existence within the sex work culture, in part to limit exposure to stigma, which has implications for access to support as well as the influence of peer norms regarding sexual risk behavior and health seeking behaviors such as HIV testing. Further research is needed to tailor prevention and HIV testing efforts to reflect the distinct sexual health "cultures" that distinguish these two populations of MSW in Lebanon. PMID:25950906

  1. An exploratory study of HIV risk behaviours and testing among male sex workers in Beirut, Lebanon

    PubMed Central

    Aunon, Frances M.; Wagner, Glenn J.; Maher, Rabih; Khouri, Danielle; Kaplan, Rachel L.; Mokhbat, Jacques

    2015-01-01

    Male sex workers (MSW) are a particularly high-risk subset of men who have sex with men in Lebanon and report higher numbers of sex partners and lower rates of condom use. The purpose was to explore the factors influencing sexual risk behaviors and HIV testing among MSW. Qualitative interviews were conducted with 16 MSW living in Beirut and working in bathhouses (hammam) or as escorts; content analysis identified emergent themes. Escorts reported more consistent condom use with clients and HIV testing than hammam MSW, with influential factors including HIV risk knowledge and perceived risk susceptibility, job security, and internalized stigma and related feelings of self-worth and fatalism regarding health and HIV risk. In contrast, both groups of MSW typically opted not to condoms with nonclient sex partners, in an effort to differentiate sex for work versus pleasure. The uptake of HIV testing was limited by concerns about the confidentiality of the test results and fear of repercussions of a positive test result for their health and employment. The respondents described an insular existence within the sex work culture, in part to limit exposure to stigma, which has implications for access to support as well as the influence of peer norms regarding sexual risk behavior and health seeking behaviors such as HIV testing. Further research is needed to tailor prevention and HIV testing efforts to reflect the distinct sexual health “cultures” that distinguish these two populations of MSW in Lebanon. PMID:25950906

  2. Psychosocial factors in association with condom use during commercial sex among migrant male sex workers living in Shenzhen, mainland China who serve cross-border Hong Kong male clients.

    PubMed

    Lau, Joseph T F; Cai, Wen-De; Tsui, Hi Yi; Chen, Lin; Cheng, Jin-Quan

    2009-10-01

    Male sex workers serving Hong Kong male clients in Shenzhen were surveyed (n = 199); 98.9% had been in Shenzhen for < or =3 years; 83.4% served local male clients; 82.8% had no family members/relatives in Shenzhen; 58.3% depended exclusively on sex work; 73% were bothered by one's sex work; and 81.7% found financial support unavailable when needed. About 29.1% had had unprotected anal intercourse (UAI) with Hong Kong male clients in the last month. UAI behavior was associated with exposure to HIV prevention services (OR = 0.08) and poor social support, being bothered by the sex work, substance use, and type of sex work venue (OR = 2.92-5.96). PMID:19690951

  3. Cisgender male and transgender female sex workers in South Africa: gender variant identities and narratives of exclusion.

    PubMed

    Samudzi, Zoe; Mannell, Jenevieve

    2016-01-01

    Sex workers are often perceived as possessing 'deviant' identities, contributing to their exclusion from health services. The literature on sex worker identities in relation to health has focused primarily on cisgender female sex workers as the 'carriers of disease', obscuring the experiences of cisgender male and transgender sex workers and the complexities their gender identities bring to understandings of stigma and exclusion. To address this gap, this study draws on 21 interviews with cisgender male and transgender female sex workers receiving services from the Sex Workers Education and Advocacy Taskforce in Cape Town, South Africa. Our findings suggest that the social identities imposed upon sex workers contribute to their exclusion from public, private, discursive and geographic spaces. While many transgender female sex workers described their identities using positive and empowered language, cisgender male sex workers frequently expressed shame and internalised stigma related to identities, which could be described as 'less than masculine'. While many of those interviewed felt empowered by positive identities as transgender women, sex workers and sex worker-advocates, disempowerment and vulnerability were also linked to inappropriately masculinised and feminised identities. Understanding the links between gender identities and social exclusion is crucial to creating effective health interventions for both cisgender men and transgender women in sex work. PMID:26242843

  4. 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 receptorα, 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

  5. Sex differences in orbitofrontal connectivity in male and female veterans with TBI.

    PubMed

    McGlade, Erin; Rogowska, Jadwiga; Yurgelun-Todd, Deborah

    2015-09-01

    More female soldiers are nowserving in combat theaters than at any other time. However, little is known about possible sex differences underlying the neuropathology and manifestation of one of modern war's signature injuries, traumatic brain injury (TBI). The paucity of information regarding sex differences in TBI is particularly evident when examining changes in executive function and emotion regulation associated with post concussive events. The current study objective was to observe whether patterns of orbitofrontal (OFC) functional connectivity would differ between female veterans with TBI and their male counterparts. The study further sought to determine whether OFC connectivity might be differentially associated with clinical measures of aggression and hostility. Seventeen female veterans and 24 male veterans, age 18 to 25, who met criteria for TBI completed resting state magnetic resonance imaging (MRI) and clinical assessment measures. Imaging data were analyzed using left and right seed regions of the OFC, and regression analyses were conducted to observe the relationship between resting state connectivity and self-reported aggression. Females and males in this study differed in OFC connectivity, with females demonstrating greater connectivity between left and right OFC and parietal and occipital regions and males demonstrating greater connectivity between left and right OFC and frontal and temporal regions. Significant associations between resting state connectivity and clinical measures were found only in male veterans. These findings suggest that TBI may interact with sex-specific patterns of brain connectivity in male and female veterans and exert divergent effects on clinical profiles of aggression post-injury. PMID:25864195

  6. 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

  7. Male territoriality and 'sex confusion' in recently adapted lizards at White Sands.

    PubMed

    Robertson, J M; Rosenblum, E B

    2010-09-01

    The evolution of intersexual interactions, like mate choice, during ecological speciation has received widespread attention. However, changes in intrasexual interactions, like male territoriality, during ecological divergence are largely unexamined. We conducted field experiments with adaptively diverged populations of the eastern fence lizard (Sceloporus undulatus) to determine whether territorial males behaved differently towards ecologically similar vs. dissimilar intruders. We performed trials with light-coloured males from White Sands, New Mexico and dark-coloured males from the surrounding desert. We found that intruders from White Sands elicited more aggression than intruders from dark-soil habitat. We also documented a case of 'sex confusion' where white-sand males courted dark-soil intruders. We found population differences in signalling patch size that can explain both aggression bias and sex misidentification. We argue that direct selection (for population recognition or optimal signal transmission) and indirect selection (by-products of ecological adaptation) should influence both intersexual and intrasexual interactions during ecological speciation. PMID:20695966

  8. Agency-Based Male Sex Work: A Descriptive Focus on Physical, Personal, and Social Space

    PubMed Central

    Smith, Michael D.; Grov, Christian; Seal, David W.

    2009-01-01

    Thirty male sex workers (MSWs) from a single agency participated in a qualitative interview about social and occupational aspects of their lives. MSWs established physical (defined areas where clients were not invited) and psychological (limitations of relationship with clients, other escorts, and the agency manager) boundaries to construct personal and professional space regarding sex work. Physical and psychological boundaries often were blended (e.g., bringing friends/family to the agency, utilizing the agency as a drop-in community center). The agency further mitigated negative aspects of sex work by providing job training, social support, stigma management, and dual-use space. Actors co-created a context wherein business could be conducted while meeting MSWs' psychosocial needs. PMID:19779572

  9. Awareness of Human Papillomavirus Vaccine Among Adolescent African American Males Who Have Sex with Males: a Pilot Study.

    PubMed

    Onyeabor, Onyekachi S; Martin, Nicolle; Orish, Verner N; Sanyaolu, Adekunle O; Iriemenam, Nnaemeka C

    2015-09-01

    African American adolescent males who have sex with males (MSMs) have a high prevalence of sexually transmitted diseases (STDs) that has been directly linked to lack of access to primary care providers and reluctance to disclose their sexuality. The human papillomavirus (HPV) is the most common STD with more than 40 different serotypes and can lead to anal/genital warts as well as oral and genital cancers. The HPV vaccine if taken prior to an adolescent becoming sexually active serves a prophylactic function. The HPV vaccine is approved by the Food and Drug Administration (FDA) for girls and boys; however, HPV vaccination rates among adolescents within different minority and underserved communities have been disappointing even though these groups are disproportionately infected with the HPV virus and certain male-specific cancers. Little is known about the uptake of the vaccine among African American MSMs and thus the aim of this study. This qualitative study is based on the health belief model and assessed participants' level of awareness of HPV, the HPV vaccine, and HPV-related illnesses among 24 African American male adolescents between 16 and 18 years old who self identify as MSMs. As part of a larger study, two focus groups were conducted for African American MSMs. Participants failed to understand their potential risk for HPV given the higher rates of STD infection experienced by MSMs. They expressed very little knowledge of the HPV vaccine and are also not aware of the complications of HPV virus infection. However, they were very eager to know more about the virus and the vaccine. This study demonstrates the need for the development of health communication intervention and more research targeting African American MSMs and also the need for policy change towards making the HPV vaccine routine for males especially adolescents at no cost. PMID:26863459

  10. Associations of lead and cadmium with sex hormones in adult males.

    PubMed

    Kresovich, Jacob K; Argos, Maria; Turyk, Mary E

    2015-10-01

    Heavy metal exposures are ubiquitous in the environment and their relation to sex hormones is not well understood. This paper investigates the associations between selected heavy metals (lead and cadmium) and sex hormones (testosterone, free testosterone, estradiol, free estradiol) as well as other major molecules in the steroid biosynthesis pathway (androstanedione glucuronide and sex-hormone binding globulin (SHBG)). Blood lead and cadmium were selected as biomarkers of exposure, and tested for associations in males using National Health and Nutritional Examination Survey (NHANES) data from 1999-2004. After adjustment for age, race, body mass index, smoking status, diabetes and alcohol intake, blood lead was positively associated with testosterone and SHBG while blood cadmium was positively associated with SHBG. After controlling for additional heavy metal exposure, the associations between lead and testosterone as well as cadmium and SHBG remained significant. Furthermore, the association between blood lead and testosterone was modified by smoking status (P for interaction=0.011), diabetes (P for interaction=0.021) and blood cadmium (P for interaction=0.029). The association between blood cadmium and SHBG levels was modified by blood lead (P for interaction=0.004). This study is the most comprehensive investigation to date regarding the association between heavy metals and sex hormones in males. PMID:26093239

  11. 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

  12. 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

  13. Preventing HIV Transmission Among Partners of HIV-Positive Male Sex Workers in Mexico City: A Modeling Study.

    PubMed

    Monteiro, João Filipe G; Marshall, Brandon D L; Escudero, Daniel; Sosa-Rubí, Sandra G; González, Andrea; Flanigan, Timothy; Operario, Don; Mayer, Kenneth H; Lurie, Mark N; Galárraga, Omar

    2015-09-01

    Mexico has a concentrated HIV epidemic, with male sex workers constituting a key affected population. We estimated annual HIV cumulative incidence among male sex workers' partners, and then compared incidence under three hypothetical intervention scenarios: improving condom use; and scaling up HIV treatment as prevention, considering current viral suppression rates (CVS, 60.7 %) or full viral suppression among those treated (FVS, 100 %). Clinical and behavioral data to inform model parameterization were derived from a sample (n = 79) of male sex workers recruited from street locations and Clínica Condesa, an HIV clinic in Mexico City. We estimated annual HIV incidence among male sex workers' partners to be 8.0 % (95 % CI: 7.3-8.7). Simulation models demonstrated that increasing condom use by 10 %, and scaling up HIV treatment initiation by 50 % (from baseline values) would decrease the male sex workers-attributable annual incidence to 5.2, 4.4 % (CVS) and 3.2 % (FVS), respectively. Scaling up the number of male sex workers on ART and implementing interventions to ensure adherence is urgently required to decrease HIV incidence among male sex workers' partners in Mexico City. PMID:25307025

  14. Persistence of an extreme male-biased adult sex ratio in a natural population of polyandrous bird.

    PubMed

    Kosztolnyi, A; Barta, Z; Kpper, C; Szkely, T

    2011-08-01

    In a number of insects, fishes and birds, the conventional sex roles are reversed: males are the main care provider, whereas females focus on matings. The reversal of typical sex roles is an evolutionary puzzle, because it challenges the foundations of sex roles, sexual selection and parental investment theory. Recent theoretical models predict that biased parental care may be a response to biased adult sex ratios (ASRs). However, estimating ASR is challenging in natural populations, because males and females often have different detectabilities. Here, we use demographic modelling with field data from 2101 individuals, including 579 molecularly sexed offspring, to provide evidence that ASR is strongly male biased in a polyandrous bird with male-biased care. The model predicts 6.1 times more adult males than females (ASR=0.860, proportion of males) in the Kentish plover Charadrius alexandrinus. The extreme male bias is consistent between years and concordant with experimental results showing strongly biased mating opportunity towards females. Based on these results, we conjecture that parental sex-role reversal may occur in populations that exhibit extreme male-biased ASR. PMID:21749544

  15. The costs of risky male behaviour: sex differences in seasonal survival in a small sexually monomorphic primate

    PubMed Central

    Kraus, Cornelia; Eberle, Manfred; Kappeler, Peter M

    2008-01-01

    Male excess mortality is widespread among mammals and frequently interpreted as a cost of sexually selected traits that enhance male reproductive success. Sex differences in the propensity to engage in risky behaviours are often invoked to explain the sex gap in survival. Here, we aim to isolate and quantify the survival consequences of two potentially risky male behavioural strategies in a small sexually monomorphic primate, the grey mouse lemur Microcebus murinus: (i) most females hibernate during a large part of the austral winter, whereas most males remain active and (ii) during the brief annual mating season males roam widely in search of receptive females. Using a 10-year capturemarkrecapture dataset from a population of M. murinus in Kirindy Forest, western Madagascar, we statistically modelled sex-specific seasonal survival probabilities. Surprisingly, we did not find any evidence for direct survival benefits of hibernationwinter survival did not differ between males and females. By contrast, during the breeding season males survived less well than females (sex gap: 16%). Consistent with the risky male behaviour hypothesis, the period for lowered male survival was restricted to the short mating season. Thus, sex differences in survival in a promiscuous mammal can be substantial even in the absence of sexual dimorphism. PMID:18426751

  16. The costs of risky male behaviour: sex differences in seasonal survival in a small sexually monomorphic primate.

    PubMed

    Kraus, Cornelia; Eberle, Manfred; Kappeler, Peter M

    2008-07-22

    Male excess mortality is widespread among mammals and frequently interpreted as a cost of sexually selected traits that enhance male reproductive success. Sex differences in the propensity to engage in risky behaviours are often invoked to explain the sex gap in survival. Here, we aim to isolate and quantify the survival consequences of two potentially risky male behavioural strategies in a small sexually monomorphic primate, the grey mouse lemur Microcebus murinus: (i) most females hibernate during a large part of the austral winter, whereas most males remain active and (ii) during the brief annual mating season males roam widely in search of receptive females. Using a 10-year capture-mark-recapture dataset from a population of M. murinus in Kirindy Forest, western Madagascar, we statistically modelled sex-specific seasonal survival probabilities. Surprisingly, we did not find any evidence for direct survival benefits of hibernation-winter survival did not differ between males and females. By contrast, during the breeding season males survived less well than females (sex gap: 16%). Consistent with the 'risky male behaviour' hypothesis, the period for lowered male survival was restricted to the short mating season. Thus, sex differences in survival in a promiscuous mammal can be substantial even in the absence of sexual dimorphism. PMID:18426751

  17. 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

  18. Primary Sex Determination in Drosophila melanogaster Does Not Rely on the Male-Specific Lethal Complex.

    PubMed

    Erickson, James W

    2016-02-01

    It has been proposed that the Male Specific Lethal (MSL) complex is active in Drosophila melanogaster embryos of both sexes prior to the maternal-to-zygotic transition. Elevated gene expression from the two X chromosomes of female embryos is proposed to facilitate the stable establishment of Sex-lethal (Sxl) expression, which determines sex and represses further activity of the MSL complex, leaving it active only in males. Important supporting data included female-lethal genetic interactions between the seven msl genes and either Sxl or scute and sisterlessA, two of the X-signal elements (XSE) that regulate early Sxl expression. Here I report contrary findings that there are no female-lethal genetic interactions between the msl genes and Sxl or its XSE regulators. Fly stocks containing the msl3(1) allele were found to exhibit a maternal-effect interaction with Sxl, scute, and sisterlessA mutations, but genetic complementation experiments showed that msl3 is neither necessary nor sufficient for the female-lethal interactions, which appear to be due to an unidentified maternal regulator of Sxl. Published data cited as evidence for an early function of the MSL complex in females, including a maternal effect of msl2, have been reevaluated and found not to support a maternal, or other effect, of the MSL complex in sex determination. These findings suggest that the MSL complex is not involved in primary sex determination or in X chromosome dosage compensation prior to the maternal-to-zygotic transition. PMID:26614741

  19. Male-biased sex ratios of fish embryos near a pulp mill: temporary recovery after a short-term shutdown.

    PubMed Central

    Larsson, D G Joakim; Frlin, Lars

    2002-01-01

    In a previous study we showed that broods from the viviparous eelpout Zoarces viviparus were significantly male biased in 1998 in the vicinity of a large kraft pulp mill on the Swedish Baltic coast. One suggested hypothesis was that masculinizing compounds in the effluent were affecting gonadal differentiation of the embryos, resulting in skewed sex ratios. In this article, we present further evidence for a causal relationship between the exposure to the effluent and the male-biased sex ratios. Analyses of historical samples showed that the eelpout produced male-biased broods close to the mill in 1997 in addition to 1998. During 1999, the mill was shut down for 17 days, coinciding with the period when the gonads of the eelpout embryos differentiate. Subsequently, in the fall of 1999, the sex ratios were no longer male biased; however, the following year (2000), a significant male bias reappeared. Investigations at 13 sites for up to 4 years showed a relatively stable sex ratio around 50/50, with the exceptions by the mill and with few observations of deviating ratios at other sites. Several reports document endocrine disturbances in fish near pulp and paper mills, including the expression of male secondary sex characters in female fish. The repeatedly identified male bias at the investigated mill, the normalization after mill shutdown, and the reappearance the following year indicate that pulp mill effluents also can affect sex ratios of nearby fish. PMID:12153752

  20. First evidence of sex chromosome pre-reduction in male meiosis in the Miridae bugs (Heteroptera).

    PubMed

    Grozeva, Snejana; Nokkala, Seppo; Simov, Nikolay

    2006-01-01

    The karyotype and male meiosis of Macrolophus costalis Fieber (Insecta, Heteroptera, Miridae) were studied using C-banding, AgNOR-banding and DNA sequence specific fluorochrome staining. The chromosome formula of the species is 2n = 28(24+X1X2X3Y). Male meiotic prophase is characterized by a prominent condensation stage. At this stage, two sex chromosomes, "X" and Y are positively heteropycnotic and always appeared together, while in autosomal bivalents homologous chromosomes were aligned side by side along their entire length, that is, meiosis is achiasmatic. At metaphase I, "X" and Y form a pseudobivalent and orient to the opposite poles. At early anaphase I, the "X" chromosome disintegrates into three separate small chromosomes, X1, X2, and X3. Hence both the autosomes and sex chromosomes segregate reductionally in the first anaphase, and separate equationally in the second anaphase. This is the first evidence of sex chromosome pre-reduction in the family Miridae. Data on C-heterochromatin distribution and its composition in the chromosomes of this species are discussed. PMID:17044253

  1. Sex differences in kin bias at maturation: Male rhesus macaques prefer paternal kin prior to natal dispersal.

    PubMed

    Widdig, Anja; Langos, Doreen; Kulik, Lars

    2016-01-01

    Dispersal and mating patterns are known to affect the availability of both maternal and paternal kin within social groups, with important effects on the evolution of sociality. It is generally assumed that the philopatric sex forms stronger social bonds than the dispersing sex, possibly as a result of reduced kin availability for the dispersing sex after departure. However, few primate studies have directly compared whether sex differences in association patterns, particular with kin, are already present prior to dispersal when kin availability should be the same for both sexes. Here, we compared affiliative and aggressive interactions in a female philopatric species, the rhesus macaque (Macaca mulatta), to test whether sex differences in kin bias already occur around the age of maturation, when both sexes still live together with kin in their natal group. Our data confirmed that kin availability was the same for both sexes prior to male dispersal. Similar kin availability was partially reflected by comparable association patterns, as both females and males preferentially interacted with maternal kin. However, females had stronger affiliative bonds with maternal kin than males of the same age, indicating that kin associations not only depended upon kin availability, but were also sex-specific. Similarly, males were significantly more likely to affiliate with paternal kin than non-kin, as compared to females, suggesting that males discriminated paternal kin from non-kin earlier in life than females. Males might have a stronger need than females to affiliate with paternal kin due to a reduced integration in the matrilineal family prior to dispersal and the high availability of paternally related age-peers, with whom males could potentially migrate. Females, in contrast, form stronger affiliations with maternal kin, which may enhance their offspring's survival. More comparative studies are needed to understand the impact of different dispersal regimes on patterns of kin associations. Am. J. Primatol. 78:78-91, 2016. 2016 Wiley Periodicals, Inc. PMID:25810077

  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. 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 MDC1ATM 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

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

    PubMed

    Nureña, César R; Zúñiga, Mario; Zunt, Joseph; Mejía, Carolina; Montano, Silvia; Sánchez, Jorge L

    2011-11-01

    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 sociocultural 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

  5. Sex chromosome pre-reduction in male meiosis of Lethocerus patruelis (Stl, 1854) (Heteroptera, Belostomatidae) with some notes on the distributionofthe 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 thebreeding and nymphal development of this species in Bulgaria is provided. PMID:24039515

  6. Where have all the females gone? Male biased sex-ratio in Arctodiaptomus alpinus (Imhof, 1885) in alpine lakes

    NASA Astrophysics Data System (ADS)

    Žibrat, U.; Brancelj, A.

    2009-04-01

    In populations with both males and females sex-ratio is one of the driving forces of population dynamics. It influences fecundity, inbreeding and social interactions. Sex-ratio is affected by several biotic and abiotic factors, either by selective killing of one sex or by inducing migrations. In alpine lakes of Triglav National Park, Slovenia, an extremely male biased sex-ratio in Arctodiaptomus alpinus (Imhof, 1885) was regularly observed since 1992. We analysed population dynamics and sex-ratio of A. alpinus in three alpine lakes (Jezero v Ledvicah, Rjavo jezero and Zgornje Kriško jezero) from Triglav National Park in Slovenia. In addition to seasonal dynamics we also researched long-term changes in sex-ratio (in a period of 11 years from autumn samples) as a result of increased air-temperature, and zooplankton diurnal vertical migrations. Adults of both sexes were found to appear at the same time in the water collumn with males prevailing throughout the season. A similar trend was found in copepodites CV. The percent of adult females began increasing in late summer, when there were no more copepodites and recrutation from copepodites CV to adults stopped, while male mortality increased. All cohorts of A. alpinus were found to perform diurnal vertical migrations. Both adult and CV females remained close to the bottom during the day and migrated vertically during the night. Results of the long-term study show no changes in sex-ratio in autumn.

  7. Sex differences in the genetic architecture of lifespan in a seed beetle: extreme inbreeding extends male lifespan

    PubMed Central

    Bilde, Trine; Maklakov, Alexei A; Meisner, Katrine; la Guardia, Lucia; Friberg, Urban

    2009-01-01

    Background Sex differences in lifespan are ubiquitous throughout the animal kingdom but the causes underlying this phenomenon remain poorly understood. Several explanations based on asymmetrical inheritance patterns (sex chromosomes or mitochondrial DNA) have been proposed, but these ideas have rarely been tested experimentally. Alternatively, sexual dimorphism in lifespan could result from sex-specific selection, caused by fundamental differences in how males and females optimize their fitness by allocating resources into current and future reproduction. Results Here we used sex-specific responses to inbreeding to study the genetic architecture of lifespan and mortality rates in Callosobruchus maculatus, a seed beetle that shows sexual dimorphism in lifespan. Two independent assays revealed opposing sex-specific responses to inbreeding. The combined data set showed that inbred males live longer than outbred males, while females show the opposite pattern. Both sexes suffered reduced fitness measured as lifetime reproductive success as a result of inbreeding. Conclusion No model based on asymmetrical inheritance can explain increased male lifespan in response to inbreeding. Our results are however compatible with models based on sex-specific selection on reproductive strategies. We therefore suggest that sex-specific differences in lifespan in this species primarily result from sexually divergent selection. PMID:19200350

  8. A new male sex-pheromone and novel cuticular cues for chemical communication in Drosophila

    PubMed Central

    Dreisewerd, Klaus; Luftmann, Heinrich; Mthing, Johannes; Pohlentz, Gottfried; Kravitz, Edward A.

    2009-01-01

    Summary Background In many insect species, cuticular hydrocarbons serve as pheromones that can mediate complex social behaviors. In Drosophila melanogaster, several hydrocarbons including the male sex pheromone 11-cis-vaccenyl acetate (cVA) and female-specific 7,11-dienes influence courtship behavior and can function as cues for short-term memory associated with the mating experience. Behavioral and physiological studies suggest that other unidentified chemical communication cues are likely to exist. To more fully characterize the hydrocarbon profile of the D. melanogaster cuticle, we applied direct ultraviolet laser desorption/ionization orthogonal time-of-flight mass spectrometry (UV-LDI-o-TOF MS) and analyzed the surface of intact fruit flies at a spatial resolution of approximately 200 ?m. Results We report the chemical and spatial characterization of 28 species of cuticular hydrocarbons, including a new major class of oxygen-containing compounds. Using UV-LDI MS, pheromones previously shown to be expressed exclusively by one sex, e.g. cVA, 7,11-heptacosadiene, and 7,11-nonacosadiene, appear to be found on both male and female flies. In males, cVA co-localizes at the tip of the ejaculatory bulb with a second acetylated hydrocarbon named CH503. We describe the chemical structure of CH503 as 3-O-acetyl-1,3-dihydroxy-octacosa-11,19-diene and show one behavioral role for this compound as a long-lived inhibitor of male courtship. Like cVA, CH503 is transferred from males to females during mating. Unlike cVA, CH503 remains on the surface of females for at least 10 days. Conclusions Oxygenated hydrocarbons comprise one major previously undescribed class of compounds on the Drosophila cuticular surface. In addition to cVA, a newly-discovered long chain acetate, CH503, serves as a mediator of courtship-related chemical communication. PMID:19615904

  9. Unreported Male Sex Partners Among Men with Newly Diagnosed HIV Infection - North Carolina, 2011-2013.

    PubMed

    Wu, Hsiu; Hightow-Weidman, Lisa B; Gay, Cynthia L; Zhang, Xinjian; Beagle, Steve; Hall, Laura; Jackson, Tonyka; Marmorino, Jenni; Do, Ann N; Peters, Philip J

    2015-09-25

    Human immunodeficiency virus (HIV) prevention interventions, such as preexposure prophylaxis (PrEP), are often targeted to men who have sex with men (MSM) who self-report high-risk behaviors. Data from a prospective study evaluating methods to detect acute HIV infection among a primarily young (aged <25 years) and black or African American (African American) population from North Carolina were analyzed. In the study, participants were asked about risk behaviors during pretest counseling (at the time of testing) and then during a partner services interview (at HIV diagnosis). Participants whose disclosure of sexual risk behaviors during pretest counseling was different from their disclosure of sexual risk behaviors during their partner services interview were identified, and factors associated with these discordant responses were examined. Among 113 HIV-infected men, 26 (23.0%) did not disclose male sex partners at pretest counseling, but subsequently did disclose this information during their partner services interview. When compared with men who disclosed having male partners at pretest counseling, these 26 MSM who did not disclose male partners during pretest counseling were found to have a similar number of male partners during contact tracing, but were more likely to have a female partner (30.8% versus 6.9%). In addition, the proportions of MSM found to have at least one HIV-infected partner were similar for both groups (MSM who disclosed having male partners during pretest counseling and those who did not). To better customize HIV prevention interventions for MSM, HIV prevention programs might consider using novel strategies to accurately assess risk in this population. PMID:26401589

  10. Identification and Synthesis of the Male-produced Sex Pheromone of the Stink Bug, Pellaea stictica.

    PubMed

    Fvaro, Carla F; Millar, Jocelyn G; Zarbin, Paulo H G

    2015-09-01

    Stink bugs are major pests of a wide variety of agricultural crops worldwide. The species Pellaea stictica is a Neotropical stink bug found in several South American countries. Chromatographic analyses of volatiles released by adults of this species showed that males produce a sex-specific compound, and bioassays with a Y-tube olfactometer showed that the compound was attractive only to females, confirming that it is a sex pheromone. Gas chromatography coupled to mass spectrometry and Fourier transform infrared analyses of the natural compound and several derivatives suggested that the structure was an alcohol with a saturated carbon chain and several methyl branches. After synthesis of two proposed structures, the pheromone of P. stictica was identified as a novel compound, 2,4,8,13-tetramethyltetradecan-1-ol. Laboratory bioassays showed that the synthesized mixture of stereoisomers of 2,4,8,13-tetramethyltetradecan-1-ol was as attractive to P. stictica females as the natural pheromone. PMID:26318441

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

    PubMed Central

    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

  12. 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.

  13. The fatty acid elongase Bond is essential for Drosophila sex pheromone synthesis and male fertility

    PubMed Central

    Ng, Wan Chin; Chin, Jacqueline S. R.; Tan, Kah Junn; Yew, Joanne Y.

    2015-01-01

    Insects use a spectacular variety of chemical signals to guide their social behaviours. How such chemical diversity arises is a long-standing problem in evolutionary biology. Here we describe the contribution of the fatty acid elongase Bond to both pheromone diversity and male fertility in Drosophila. Genetic manipulation and mass spectrometry analysis reveal that the loss of bond eliminates the male sex pheromone (3R,11Z,19Z)-3-acetoxy-11,19-octacosadien-1-ol (CH503). Unexpectedly, silencing bond expression severely suppresses male fertility and the fertility of conspecific rivals. These deficits are rescued on ectopic expression of bond in the male reproductive system. A comparative analysis across six Drosophila species shows that the gain of a novel transcription initiation site is correlated with bond expression in the ejaculatory bulb, a primary site of male pheromone production. Taken together, these results indicate that modification of cis-regulatory elements and subsequent changes in gene expression pattern is one mechanism by which pheromone diversity arises. PMID:26369287

  14. 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.

  15. Influence of sex and age on morphological organ damage after hemorrhagic shock.

    PubMed

    Mees, Soeren Torge; Gwinner, Maike; Marx, Kerstin; Faendrich, Fred; Schroeder, Joerg; Haier, Joerg; Kahlke, Volker

    2008-06-01

    Immune function after hemorrhagic shock (shock) and subsequent sepsis is proofed to be sex- and age-related, showing an enhanced immune function and better survival of young females and a deteriorating immune response in advanced age. However, it remains unclear if the observed sex- and age-related effects observed on the immune function mirror the histomorphological changes of the affected organs. To scrutinize a possible association, male and female CBA/J mice (young, 2-3 months; aged 18-19 months) were subjected to shock (35 + 5 mmHg for 90 min and fluid resuscitation) or sham operation. At 48 h after shock, histological specimen at definite sites were harvested (lung, small bowel, liver, and kidney) and immediately stored in 10% formalin. After paraffin embedding, hematoxylin-eosin stain and immunohistochemical stains (vascular cell adhesion molecule 1 [VCAM-1], cluster of differentiation 44 [CD44], signal transducers and activators of transcription 3 [STAT-3]) were performed. In both sexes, aged animals developed significantly increased (P < 0.05) tissue damage in all analyzed organs compared with young mice. Sex differences were noticed in the lungs of young mice, showing a significantly (P < 0.05) lower organ damage score in female animals. Sex-related differences were found for VCAM-1 and cluster of differentiation 44 expression, whereas age-related changes were observed for STAT-3. These results demonstrate that the severity of tissue damage caused by hemorrhagic shock is influenced by sex- and age-related effects. Variances in the VCAM-1 and STAT-3 expression suggest that improved immune function in female and young subjects may be responsible for less shock-induced tissue damage. PMID:17998889

  16. The impact of sex hormone concentrations on decision-making in females and males

    PubMed Central

    Derntl, Birgit; Pintzinger, Nina; Kryspin-Exner, Ilse; Schöpf, Veronika

    2014-01-01

    Human decision-making has been frequently studied and sex differences have been reported. Interestingly, previous results of hormone concentration on decision-making are somewhat inconsistent, regarding the impact of menstrual cycle phase in women or the influence of testosterone concentration on decision-making in women and men. However, the influence of the female sex hormone concentration (estradiol, progesterone) and the impact of oral contraceptive intake have rarely been examined and data regarding the effect of daytime variations of male testosterone are lacking. Moreover if personality factors such as sensation seeking, impulsivity, and anxiety influence decision-making, sex-specific effects, act as modulators is unclear. In the present study 71 women and 45 men were enrolled. All participants performed an evaluated decision-making task measuring risk-taking behavior on the basis of contingencies (Haegler et al., 2010), which can be carried out several times without a learning effect. Saliva samples were collected to obtain estradiol, progesterone, and testosterone levels. Additionally, all participants completed questionnaires measuring various personality factors. Data analysis revealed no sex differences in decision-making and no significant impact of testosterone concentration on behavioral performance in women or men. However, a significant negative correlation between progesterone concentration of women in the luteal phase and their performance in the risk-averse condition was obtained. Interestingly, a significant correlation between trait anxiety and decision-making occurred in females and males. Despite similar risky decision-making of women and men and no influence of testosterone concentration, menstrual cycle phase showed an effect on risk taking in women. In contrary to other studies, our findings provide rather subtle evidence for hormonal influences in decision-making, which may be primarily explained by task factors. PMID:25414632

  17. Sex discrimination: how do we tell the difference between male and female faces?

    PubMed

    Bruce, V; Burton, A M; Hanna, E; Healey, P; Mason, O; Coombes, A; Fright, R; Linney, A

    1993-01-01

    People are remarkably accurate (approaching ceiling) at deciding whether faces are male or female, even when cues from hair style, makeup, and facial hair are minimised. Experiments designed to explore the perceptual basis of our ability to categorise the sex of faces are reported. Subjects were considerably less accurate when asked to judge the sex of three-dimensional (3-D) representations of faces obtained by laser-scanning, compared with a condition where photographs were taken with hair concealed and eyes closed. This suggests that cues from features such as eyebrows, and skin texture, play an important role in decision-making. Performance with the laser-scanned heads remained quite high with 3/4-view faces, where the 3-D shape of the face should be easiest to see, suggesting that the 3-D structure of the face is a further source of information contributing to the classification of its sex. Performance at judging the sex from photographs (with hair concealed) was disrupted if the photographs were inverted, which implies that the superficial cues contributing to the decision are not processed in a purely 'local' way. Performance was also disrupted if the faces were shown in photographic negatives, which is consistent with the use of 3-D information, since negation probably operates by disrupting the computation of shape from shading. In 3-D, the 'average' male face differs from the 'average' female face by having a more protuberant nose/brow and more prominent chin/jaw. The effects of manipulating the shapes of the noses and chins of the laser-scanned heads were assessed and significant effects of such manipulations on the apparent masculinity or femininity of the heads were revealed. It appears that our ability to make this most basic of facial categorisations may be multiply determined by a combination of 2-D, 3-D, and textural cues and their interrelationships. PMID:8474840

  18. 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

  19. 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, Jrgen

    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

  20. Burden of HIV and Syphilis: A Comparative Evaluation between Male Sex Workers and Non-Sex-Worker Men Who Have Sex with Men in Urban China

    PubMed Central

    Tang, Weiming; Mahapatra, Tanmay; Liu, Fengying; Fu, Gengfeng; Yang, Bin; Tucker, Joseph D.; Zhao, Jinkou; Detels, Roger

    2015-01-01

    Background The increasing burden of sexually transmitted infections (STIs) including HIV and syphilis among male sex workers (MSWs) is a major global concern. The aim of our study was to evaluate the difference between MSWs and non-commercial MSMs in China. Methods During 2008-09, in a cross-sectional study, 2618 adult MSM were recruited through respondent-driven and snowball sampling from seven cities of China. Information regarding socio-demographics, risk behaviors, HIV-related knowledge and STI-related symptoms were collected and participants were tested for HIV and syphilis. Results Among 2618 participating MSM, 9.97% sold sex to males. HIV prevalence was 7.45% (6.13% among MSWs and 7.59% among non-MSW MSM) and syphilis prevalence was 14.32% (10.73% for MSWs and 14.72% for non-MSW MSM). Compared to non-MSW MSM, MSWs were more likely to be younger (adjusted odds ratio: aOR = 0.91, 95% confidence interval: 95%CI=0.88-0.93), never married (aOR = 4.38, 95% CI = 2.38-6.80), less educated, heterosexual (aOR = 13.04, 95% CI = 6.08-27.95), less knowledgeable regarding HIV (aOR = 0.70, 95% CI=0.51-0.96), experiencing symptoms of STI (aOR = 2.16, 95% CI = 1.47-3.19), engaging in condomless vaginal intercourse (aOR = 2.16, 95% CI = 1.47-3.19) and less likely to engage in condomless anal intercourse (aOR = 0.62, 95% CI = 0.46-0.85). Conclusions High HIV and syphilis prevalence warranted urgent intervention targeting MSWs as a separate sentinel group for efficient surveillance owing to their different distribution from non-MSW MSM. Although male sex workers and non-commercial homosexuals have similar rates of HIV and syphilis, MSWs have different characteristics which should be considered in designing intervention programs targeting them. PMID:25961721

  1. Evolutionary Consequences of Male Driven Sexual Selection and Sex-Biased Fitness Modifications in Drosophila melanogaster and Members of the simulans Clade

    PubMed Central

    Jagadeeshan, Santosh; Haerty, Wilfried; Moglinicka, Monika; Ahuja, Abha; De Vito, Scot; Singh, Rama S.

    2015-01-01

    Males have evolved a variety of behavioral, morphological, and physiological traits to manipulate their mates in order to maximize their chances of success. These traits are bound to influence how females respond to male behaviors and influence the nature of sexual selection/conflict. A common consequence of aggressive male mating strategies in Drosophila melanogaster is the reduction of female lifespan. Our study shows that this is common across members of the simulans clade. Reduced life expectancy of females implies that female contribution to a population is less than that of males per generation. Fitness differences between the sexes in every generation will invariably affect overall population fitness. How natural selection responds to the female deaths and thereby the unequal fitness of the sexes has rarely been addressed. We shed light on this issue and provide evidence, which suggests that additional gains of fitness by males due to their longevity and continued mating may provide one explanation as to why the loss of female fitness may be invisible (effectively neutral) to natural selection. Male driven sexual selection and additional, transgenerational gains of male fitness can be an important force of evolutionary change and need to be tested with other organisms. PMID:26421208

  2. Self-Organization in the Battle of the Sexes

    NASA Astrophysics Data System (ADS)

    Alonso-Sanz, Ramón

    This paper presents a spatial version of the iterated battle of the sexes game in which every one individual plays with his nearest partners and imitates the optimal strategy of his nearest mate neighbors. 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.

  3. MULTIPLE-MATING OF MALE AND FEMALE CODLING MOTH (LEPIDOPTERA: TORTRICIDAE) IN APPLE ORCHARDS TREATED WITH SEX PHEROMONE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies were conducted with codling moth, Cydia pomonella (L.), to evaluate the mating status of male and female moths in apple, Malus domestica (Borkhausen), orchards treated with and without sex pheromone dispensers. Laboratory studies first examined the effect of multiple mating of male and femal...

  4. Traumagenic Dynamics in Adult Women Survivors of Childhood Sexual Abuse vs. Adolescent Male Sex Offenders with Similar Histories.

    ERIC Educational Resources Information Center

    Edwards, Carla; Hendrix, Rebecca

    2001-01-01

    Female childhood sexual abuse survivors and adolescent male sexual offenders with a history of childhood sexual abuse were assessed using the Trauma-Related Beliefs Questionnaire. Results suggested that male sex offenders hold high levels of traumagenic beliefs common in females, especially related to trust and betrayal. (Author)

  5. Social Deficits in Male Children and Adolescents with Sex Chromosome Aneuploidy: A Comparison of XXY, XYY, and XXYY Syndromes

    ERIC Educational Resources Information Center

    Cordeiro, Lisa; Tartaglia, Nicole; Roeltgen, David; Ross, Judith

    2012-01-01

    We compare social skills in three groups of males with sex chromosome aneuploidies (SCAs) using the Social Responsiveness Scale (SRS). Participants included males with XXY (N = 102, M = 10.08 years), XYY (N = 40, M = 9.93 years), and XXYY (N = 32, M = 11.57 years). XXY had lower (better) SRS scores compared to XYY and XXYY. Scores were not

  6. The Size Advantage Model of Sex Allocation in the Protandrous Sex-Changer Crepidula fornicata: Role of the Mating System, Sperm Storage, and Male Mobility.

    PubMed

    Broquet, Thomas; Barranger, Audrey; Billard, Emmanuelle; Bestin, Anastasia; Berger, Rémy; Honnaert, Gaelle; Viard, Frédérique

    2015-09-01

    Sequential hermaphroditism is adaptive when the reproductive value of an individual varies with size or age, and this relationship differs between males and females. In this case, theory shows that the lifetime reproductive output of an individual is increased by changing sex (a hypothesis referred to as the size-advantage model). Sex-linked differences in size-fitness curves can stem from differential costs of reproduction, the mating system, and differences in growth and mortality between sexes. Detailed empirical data is required to disentangle the relative roles of each of these factors within the theory. Quantitative data are also needed to explore the role of sperm storage, which has not yet been considered with sequential hermaphrodites. Using experimental rearing and paternity assignment, we report relationships between size and reproductive success of Crepidula fornicata, a protandrous (male-first) gastropod. Male reproductive success increased with size due to the polygamous system and stacking behavior of the species, but females nonetheless had greater reproductive success than males of the same size, in agreement with the size-advantage theory. Sperm storage appeared to be a critical determinant of success for both sexes, and modeling the effect of sperm storage showed that it could potentially accelerate sex change in protandrous species. PMID:26655357

  7. 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; Kubička, 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

  8. 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

  9. Identification and validation of a new male sex-specific ISSR marker in pointed gourd (Trichosanthes dioica Roxb.).

    PubMed

    Adhikari, Sinchan; Saha, Soumen; Bandyopadhyay, Tapas Kumar; Ghosh, Parthadeb

    2014-01-01

    The aim of the present study was to develop a genetic sex marker for the pointed gourd (Trichosanthes dioica Roxb.) to allow gender determination at any stage in the life cycle. Screening of genomic DNA with intersimple sequence repeat (ISSR) primers was used to discover sex-specific touch-down polymerase chain reaction (Td-PCR) amplification products. Using pooled DNA from male and female genotypes and 42 ISSR primers, a putative male specific marker (~550 bp) was identified. DNA marker specific to male is an indication of existence of nonepigenetic factors involved in gender development in pointed gourd. The ISSR technique has proved to be a reliable technique in gender determination of pointed gourd genotypes at the seedling phenophase. The sex marker developed here could also be used as a starting material towards sequence characterization of sex linked genes for better understanding the developmental as well as evolutionary pathways in sexual dimorphism. PMID:25538949

  10. 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

  11. Identification and Validation of a New Male Sex-Specific ISSR Marker in Pointed Gourd (Trichosanthes dioica Roxb.)

    PubMed Central

    Adhikari, Sinchan; Saha, Soumen; Bandyopadhyay, Tapas Kumar

    2014-01-01

    The aim of the present study was to develop a genetic sex marker for the pointed gourd (Trichosanthes dioica Roxb.) to allow gender determination at any stage in the life cycle. Screening of genomic DNA with intersimple sequence repeat (ISSR) primers was used to discover sex-specific touch-down polymerase chain reaction (Td-PCR) amplification products. Using pooled DNA from male and female genotypes and 42 ISSR primers, a putative male specific marker (~550 bp) was identified. DNA marker specific to male is an indication of existence of nonepigenetic factors involved in gender development in pointed gourd. The ISSR technique has proved to be a reliable technique in gender determination of pointed gourd genotypes at the seedling phenophase. The sex marker developed here could also be used as a starting material towards sequence characterization of sex linked genes for better understanding the developmental as well as evolutionary pathways in sexual dimorphism. PMID:25538949

  12. Prenatal sex hormones, digit ratio, and face shape in adult males

    PubMed Central

    Weinberg, S. M.; Parsons, T. E.; Raffensperger, Z. D.; Marazita, M. L.

    2014-01-01

    Objectives Several reports have demonstrated a relationship between second to fourth digit ratio (2D:4D) and facial shape, suggesting that prenatal sex hormones play a role in the development of the craniofacial complex. Using 3D surface imaging and geometric morphometrics, we test the hypothesis that decreased digit ratio (indicative of increased prenatal androgen exposure) is associated with a more masculine facial phenotype. Methods 3D facial surface images and digit measures were collected on a sample of 151 adult males. Facial landmarks collected from the images were aligned by Procrustes superimposition and the resulting shape coordinates regressed on 2D:4D. Variations in facial shape related to 2D:4D were visualized with deformable surface warps. Results A significant statistical relationship was observed between facial shape variation and 2D:4D (p = 0.0084). Lower 2D:4D ratio in adult males was associated with increased facial width relative to height, increased mandibular prognathism, greater nasal projection, and increased upper and lower lip projection. Conclusions A statistical relationship between 2D:4D and facial shape in adult males was observed. Faces tended to look more masculine as 2D:4D decreased, suggesting a biologically plausible link between prenatal androgen exposure and the development of male facial characteristics. PMID:25257381

  13. Meiotic Sex Chromosome Inactivation Is Disrupted in Sterile Hybrid Male House Mice

    PubMed Central

    Campbell, Polly; Good, Jeffrey M.; Nachman, Michael W.

    2013-01-01

    In male mammals, the X and Y chromosomes are transcriptionally silenced in primary spermatocytes by meiotic sex chromosome inactivation (MSCI) and remain repressed for the duration of spermatogenesis. Here, we test the longstanding hypothesis that disrupted MSCI might contribute to the preferential sterility of heterogametic hybrid males. We studied a cross between wild-derived inbred strains of Mus musculus musculus and M. m. domesticus in which sterility is asymmetric: F1 males with a M. m. musculus mother are sterile or nearly so while F1 males with a M. m. domesticus mother are normal. In previous work, we discovered widespread overexpression of X-linked genes in the testes of sterile but not fertile F1 males. Here, we ask whether this overexpression is specifically a result of disrupted MSCI. To do this, we isolated cells from different stages of spermatogenesis and measured the expression of several genes using quantitative PCR. We found that X overexpression in sterile F1 primary spermatocytes is coincident with the onset of MSCI and persists in postmeiotic spermatids. Using a series of recombinant X genotypes, we then asked whether X overexpression in hybrids is controlled by cis-acting loci across the X chromosome. We found that it is not. Instead, one large interval in the proximal portion of the M. m. musculus X chromosome is associated with both overexpression and the severity of sterility phenotypes in hybrids. These results demonstrate a strong association between X-linked hybrid male sterility and disruption of MSCI and suggest that trans-acting loci on the X are important for the transcriptional regulation of the X chromosome during spermatogenesis. PMID:23307891

  14. 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

  15. Collateral consequences: implications of male incarceration rates, imbalanced sex ratios and partner availability for heterosexual Black women.

    PubMed

    Dauria, Emily F; Oakley, Lisa; Arriola, Kimberly Jacob; Elifson, Kirk; Wingood, Gina; Cooper, Hannah L F

    2015-01-01

    While studies have found correlations between rates of incarceration and sexually transmitted infections (STIs), few studies have explored the mechanisms linking these phenomena. This qualitative study examines how male incarceration rates and sex ratios influence perceived partner availability and sexual partnerships for heterosexual Black women. Semi-structured interviews were conducted with 33 Black women living in two US neighbourhoods, one with a high male incarceration rate and an imbalanced sex ratio (referred to as 'Allentown') and one with a low male incarceration rate and an equitable sex ratio (referred to as 'Blackrock'). Data were analysed using grounded theory. In Allentown, male incarceration reduced the number of available men, and participants largely viewed men available for partnerships as being of an undesirable quality. The number and desirability of men impacted on the nature of partnerships such that they were shorter, focused on sexual activity and may be with higher-risk sexual partners (e.g. transactional sex partners). In Blackrock, marriage rates contributed to the shortage of desirable male partners. By highlighting the role that the quantity and quality of male partners has on shaping sexual partnerships, this study advances current understandings of how incarceration and sex ratios shape HIV- and STI-related risk. PMID:26056724

  16. 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

  17. Expression analysis of sex-determining pathway genes during development in male and female Atlantic salmon (Salmo salar).

    PubMed

    Lubieniecki, Krzysztof P; Botwright, Natasha A; Taylor, Richard S; Evans, Brad S; Cook, Mathew T; Davidson, William S

    2015-12-01

    We studied the expression of 28 genes that are involved in vertebrate sex-determination or sex-differentiation pathways, in male and female Atlantic salmon (Salmo salar) in 11 stages of development from fertilization to after first feeding. Gene expression was measured in half-sibs that shared the same dam. The sire of family 1 was a sex-reversed female (i.e., genetically female but phenotypically male), and so the progeny of this family are all female. The sire of family 2 was a true male, and so the offspring were 50% male and 50% female. Gene expression levels were compared among three groups: 20 female offspring of the cross between a regular female and the sex-reversed female (family 1, first group), ?10 females from the cross between a regular female and a regular male (family 2, second group) and ?10 males from this same family (family 2, third group). Statistically significant differences in expression levels between males and the two groups of females were observed for two genes, gsdf and amh/mis, in the last four developmental stages examined. SdY, the sex-determining gene in rainbow trout, appeared to be expressed in males from 58 days postfertilization (dpf). Starting at 83 dpf, ovarian aromatase, cyp19a, expression appeared to be greater in both groups of females compared with males, but this difference was not statistically significant. The time course of expression suggests that sdY may be involved in the upregulation of gsdf and amh/mis and the subsequent repression of cyp19a in males via the effect of amh/mis. PMID:26330486

  18. The balancing act: exploring stigma, economic need and disclosure among male sex workers in Ho Chi Minh City, Vietnam.

    PubMed

    Closson, Elizabeth F; Colby, Donn J; Nguyen, Thi; Cohen, Samuel S; Biello, Katie; Mimiaga, Matthew J

    2015-01-01

    In Vietnam, there is an emerging HIV epidemic among men who have sex with men (MSM). Male sex workers engage in high-risk sexual behaviours that make them particularly vulnerable to HIV infection. In 2010, 23 MSM in Ho Chi Minh City (HCMC) who recently received payment for sex with another man completed in-depth qualitative interviews exploring motivations for sex work, patterns of sex work disclosure and experiences of social stigma. Interviews were recorded, transcribed and translated into English and analysed using a qualitative descriptive approach. Low wages, unstable employment and family remittances were motivating factors for MSM in HCMC to sell sex. Participants described experiences of enacted and felt social stigma related to their involvement in sex work. In response, they utilised stigma management techniques aimed at concealment of involvement in sex work. Such strategies restricted sexual communication with non-paying sex partners and potentially limited their ability to seek social support from family and friends. Departing from decontextualized depictions of sex work disclosure, our findings describe how decisions to reveal involvement in sex work are shaped by social and structural factors such as social stigma, techniques to minimise exposure to stigma, economic imperatives and familial responsibilities. PMID:25555192

  19. 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

  20. Male Sex is Associated with a Reduced Alveolar Epithelial Sodium Transport

    PubMed Central

    Kaltofen, Till; Haase, Melanie; Thome, Ulrich H.; Laube, Mandy

    2015-01-01

    Respiratory distress syndrome (RDS) is the most frequent pulmonary complication in preterm infants. RDS incidence differs between genders, which has been called the male disadvantage. Besides maturation of the surfactant system, Na+ transport driven alveolar fluid clearance is crucial for the prevention of RDS. Na+ transport is mediated by the epithelial Na+ channel (ENaC) and the Na,K-ATPase, therefore potential differences in their expression or activity possibly contribute to the gender imbalance observed in RDS. Fetal distal lung epithelial (FDLE) cells of rat fetuses were separated by sex and analyzed regarding expression and activity of the Na+ transporters. Ussing chamber experiments showed a higher baseline short-circuit current (ISC) and amiloride-sensitive ΔISC in FDLE cells of female origin. In addition, maximal amiloride-sensitive ΔISC and maximal ouabain-sensitive ΔISC of female cells were higher when measured in the presence of a permeabilized basolateral or apical membrane, respectively. The number of FDLE cells per fetus recoverable during cell isolation was also significantly higher in females. In addition, lung wet-to-dry weight ratio was lower in fetal and newborn female pups. Female derived FDLE cells had higher mRNA levels of the ENaC- and Na,K-ATPase subunits. Furthermore, estrogen (ER) and progesterone receptor (PR) mRNA levels were higher in female cells, which might render female cells more responsive, while concentrations of placenta-derived sex steroids do not differ between both genders during fetal life. Inhibition of ER-β abolished the sex differences in Na+ transport and female cells were more responsive to estradiol stimulation. In conclusion, a higher alveolar Na+ transport, possibly attributable to a higher expression of hormone receptors in female FDLE cells, provides an explanation for the well known sex-related difference in RDS occurrence and outcome. PMID:26291531

  1. Sex pheromone ofEupoecilia ambiguella female: Analysis and male response to ternary blend.

    PubMed

    Arn, H; Rauscher, S; Buser, H R; Guerin, P M

    1986-06-01

    Sex gland extracts and washes ofEupoecilia ambiguella contain 10-20 ng/female of the primary sex pheromone componentZ-9-dodecenyl acetate (Z9-12?Ac), accompanied by a number of related compounds. These areE-9-dodecenyl acetate (E9-12?Ac),Z-9-dodecen-1-ol (Z9-12?OH), saturated acetates of 12, 16, 18, and 20 carbons, and traces of a doubly unsaturated acetate, tentatively identified as a 9,11-dodecadienyl acetate. Octadecyl acetate predominates among the pheromone-related components, making up 1-2, occasionally 20-30 times the amount ofZ9-12?Ac. The same compounds were also found in field-collected females and in effluvia.Z-9-Undecenyl acetate, which is a male attractant on its own, was also found in a sample of female effluvia. A hierarchy is observed in the ethological function of the pheromone components.Z9-12?Ac is an attractant forE. ambiguella males. Dodecyl acetate (12?Ac) is not attractive on its own but augments male catch when added to the main attractant. Addition of 18?Ac augments attraction only when bothZ9-12?Ac and 12?Ac are present. Windtunnel tests demonstrate that 18?Ac also raises the disorientation threshold, as previously shown for 12?Ac. Other compounds, with the possible exception of additional saturated acetates, had either no effect on trap catch or, in the case ofE9-12?Ac,Z9-12?OH, andE-9,11-dodecadienyl acetate, were inhibitory above a certain level. A blend of roughly equal parts ofZ9-12?Ac, 12?Ac, and 18?Ac provides the best attractant blend forE. ambiguella known to date. PMID:24307121

  2. Defensive compounds and male-produced sex pheromone of the stink bug, Agroecus griseus.

    PubMed

    Fvaro, Carla F; Santos, Tatiana B; Zarbin, Paulo H G

    2012-09-01

    Agroecus griseus is a serious corn pest in Brazil. Contents of the dorsal abdominal glands (DAGs) in nymphs, and the metathoracic gland (MTG) in adults of this species were characterized and quantified. Compounds found were similar to those of other Pentatomidae species and included aliphatic hydrocarbons, aldehydes, oxo-alkenals, and esters. However, two compounds were found in the MTG that have not been described previously for this family. Mass spectrometry, infrared spectroscopy, and gas chromatographic analysis using coinjection with authentic standards confirmed the identities of the compounds as enantiopure (S)-2-methylbutyl acetate and 3-methyl-2-butenyl acetate. The five nymphal instars showed significantly different ratios of components, mainly between those of the first and later instars. No significant differences were detected in MTG contents between sexes. Gas chromatography (GC) analysis of aeration extracts of males and females showed the presence of a compound released exclusively by males. Gas chromatography - electroantennographic detection (GC-EAD) assays indicated that the male-specific compound is bioactive in females, suggesting the presence of an attractant pheromone. The mass spectrum and infrared data for this compound matched with methyl 2,6,10-trimethyltridecanoate, a sex pheromone component previously detected in the stink bugs, Euschistus heros and E. obscurus. The synthetic standard coeluted with the natural pheromone on two different GC stationary phases, confirming the proposed structure. Y-tube olfactometer assays showed that the synthetic standard was strongly attractive to females, and GC-EAD tests produced responses with antennae from females similar to those of the natural pheromone. PMID:22914958

  3. 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

  4. MicroRNAs Influence Reproductive Responses by Females to Male Sex Peptide in Drosophila melanogaster

    PubMed Central

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

    2014-01-01

    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

  5. Sex-Biased Gene Expression on the Avian Z Chromosome: Highly Expressed Genes Show Higher Male-Biased Expression

    PubMed Central

    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: 0.891.01). 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

  6. 1-Tridecenemale-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.

  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. Behavioral treatment of deviant sex-role behaviors in a male child1

    PubMed Central

    Rekers, George A.; Lovaas, O. Ivar

    1974-01-01

    This study demonstrated reinforcement control over pronounced feminine behaviors in a male child who had been psychologically evaluated as manifesting childhood cross-gender identity. The clinical history of the subject paralleled the retrospective reports of adult transsexuals, including (a) cross-gender clothing preferences, (b) actual or imaginal use of cosmetic articles, (c) feminine behavior mannerisms, (d) aversion to masculine activities, coupled with preference for girl playmates and feminine activities, (e) preference for female role, (f) feminine voice inflection and predominantly feminine content in speech, and (g) verbal statements about the desire or preference to be a girl. The subject was treated sequentially in the clinic and home environments by his mother, trained to be his therapist. The mother was taught to reinforce masculine behaviors and to extinguish feminine behaviors, by using social reinforcement in the clinic and a token reinforcement procedure in the home. During this treatment, his feminine behaviors sharply decreased and masculine behavior increased. The treatment effects were found to be largely response-specific and stimulus-specific; consequently, it was necessary to strengthen more than one masculine behavior and weaken several feminine behaviors, in both clinic and home settings. A multiple-baseline intrasubject design was used to ensure both replication and identification of relevant treatment variables. Follow-up data three years after the treatment began suggests that the boy's sex-typed behaviors have become normalized. This study suggests a preliminary step toward correcting pathological sex-role development in boys, which may provide a basis for the primary prevention of adult transsexualism or similar adult sex-role deviation. PMID:4436165

  9. The embodiment of tourism among bisexually-behaving Dominican male sex workers.

    PubMed

    Padilla, Mark B

    2008-10-01

    While theories of "structure" and social inequality have increasingly informed global health efforts for HIV prevention--with growing recognition of the linkages between large-scale political and economic factors in the distribution and impact of the HIV/AIDS epidemic--there is still little theorization of precisely how structural factors shape the very bodies and sexualities of specific populations and groups. In order to extend the theoretical understanding of these macro-micro linkages, this article examines how the growth of the tourism industry in the Dominican Republic has produced sexual practices and identities that reflect both the influence of large-scale structural processes and the resistant responses of local individuals. Drawing on social science theories of political economy, embodiment, and authenticity, I argue that an understanding of patterns of sexuality and HIV risk in the region requires analysis of how political-economic transformations related to tourism intersect with the individual experiences and practices of sexuality on the ground. The analysis draws on long-term ethnographic research with bisexually behaving male sex workers in two cities in the Dominican Republic, including participant observation, in-depth interviews, focus groups, and surveys. By examining the global and local values placed on these men's bodies and the ways sex workers use their bodies to broker tourists' pleasure, we may better understand how the large-scale structures of the tourism industry are linked to the specific meanings and practices of sexuality. PMID:18506615

  10. Influence of salazosulphapyridine and 5-aminosalicylic acid on seminal qualities and male sex hormones.

    PubMed

    Zelissen, P M; van Hattum, J; Poen, H; Scholten, P; Gerritse, R; te Velde, E R

    1988-11-01

    Seminal abnormalities are a common side effect of salazosulphapyridine (SASP) treatment. We evaluated semen qualities and sex hormone concentrations in 11 patients with inflammatory bowel disease (IBD) during SASP treatment and 4 months after replacing SASP with an oral slow-release preparation of 5-aminosalicylic acid (5-ASA). Significant improvement in sperm count (p less than 0.01), morphology (p less than 0.02), and motility (p less than 0.02) could be observed during 5-ASA therapy, in comparison with SASP treatment. Three pregnancies occurred during the study period. The serum concentrations of gonadotrophins, prolactin, and sex hormone-binding globulin were normal in all patients and not significantly different in the two treatment periods. The mean total testosterone concentration decreased significantly (p less than 0.02) after 5-ASA substitution, together with serum albumin (p less than 0.005), although all values remained within normal limits. The apparent free testosterone concentration was not significantly different in the two treatment periods. It is concluded that a significant improvement in semen quality can be obtained in male patients with IBD after replacing SASP with 5-ASA. PMID:2907823

  11. Estimating the number of male sex workers with the capture-recapture technique in Nigeria.

    PubMed

    Adebajo, Sylvia B; Eluwa, George I; Tocco, Jack U; Ahonsi, Babatunde A; Abiodun, Lolade Y; Anene, Oliver A; Akpona, Dennis O; Karlyn, Andrew S; Kellerman, Scott

    2013-12-01

    Estimating the size of populations most affected by HIV such as men who have sex with men (MSM) though crucial for structuring responses to the epidemic presents significant challenges, especially in a developing society. Using capture-recapture methodology, the size of MSM-SW in Nigeria was estimated in three major cities (Lagos, Kano and Port Harcourt) between July and December 2009. Following interviews with key informants, locations and times when MSM-SW were available to male clients were mapped and designated as "hotspots". Counts were conducted on two consecutive weekends. Population estimates were computed using a standardized Lincoln formula. Fifty-six hotspots were identified in Kano, 38 in Lagos and 42 in Port Harcourt. On a given weekend night, Port Harcourt had the largest estimated population of MSM sex workers, 723 (95% CI: 594-892) followed by Lagos state with 620 (95%CI: 517-724) and Kano state with 353 (95%CI: 332-373). This study documents a large population of MSM-SW in 3 Nigerian cities where higher HIV prevalence among MSM compared to the general population has been documented. Research and programming are needed to better understand and address the health vulnerabilities that MSM-SW and their clients face. PMID:24689319

  12. MPK-1 ERK controls membrane organization in C. elegans oogenesis via a sex determination module

    PubMed Central

    Arur, Swathi; Ohmachi, Mitsue; Berkseth, Matt; Nayak, Sudhir; Hansen, David; Zarkower, David; Schedl, Tim

    2011-01-01

    Tissues that generate specialized cell-types in a production line must coordinate developmental mechanisms with physiological demand, although how this occurs is largely unknown. In the C. elegans hermaphrodite, the developmental sex-determination cascade specifies gamete sex in the distal germline, while physiological sperm signaling activates MPK-1/ERK in the proximal germline to control plasma membrane biogenesis/organization during oogenesis. We discovered repeated utilization of a self-contained negative regulatory module, consisting of NOS-3 translational repressor, FEM-CUL-2 (E3 ubiquitin ligase) and TRA-1 (Gli transcriptional repressor), which acts both in sex-determination and in physiological demand control of oogenesis, coordinating these processes. In the distal germline, where MPK-1 is not activated, TRA-1 represses the male fate as NOS-3 functions in translational repression leading to inactivation of the FEM-CUL-2 ubiquitin ligase. In the proximal germline, sperm-dependent physiological MPK-1 activation results in phosphorylation-based inactivation of NOS-3, FEM-CUL-2 mediated degradation of TRA-1 and the promotion of membrane organization during oogenesis. PMID:21571224

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

    PubMed

    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

  14. 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

  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; Gonzlez, 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. Male mate choice relies on major histocompatibility complex class I in a sex-role-reversed pipefish.

    PubMed

    Roth, O; Sundin, J; Berglund, A; Rosenqvist, G; Wegner, K M

    2014-05-01

    Mate choice for compatible genes is often based on genes of the major histocompatibility complex (MHC). Although MHC-based mate choice is commonly observed in female choice, male mate choice remains elusive. In particular, if males have intense paternal care and are thus the choosing sex, male choice for females with dissimilar MHC can be expected. Here, we investigated whether male mate choice relies on MHC class I genes in the sex-role reversed pipefish Syngnathus typhle. In a mate choice experiment, we determined the relative importance of visual and olfactory cues by manipulating visibility and olfaction. We found that pipefish males chose females that maximize sequence-based amino acid distance between MHC class I genotypes in the offspring when olfactory cues were present. Under visual cues, large females were chosen, but in the absence of visual cues, the choice pattern was reversed. The use of sex-role reversed species thus revealed that sexual selection can lead to the evolution of male mate choice for MHC class I genes. PMID:24725009

  17. Hazardous Drinking and HIV-risk-related Behaviour among Male Clients of Female Sex Workers in Tijuana, Mexico

    PubMed Central

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

    2015-01-01

    Background and Objectives Male clients of female sex workers (FSWs) are at high risk for HIV. Whereas the HIV risks of alcohol use are well understood, less is known about hazardous alcohol use among male clients of FSWs, particularly in Mexico. We sought to identify risk factors for hazardous alcohol use and test associations between hazardous alcohol use and HIV risk behaviour among male clients in Tijuana. Method Male clients of FSWs in Tijuana (n = 400) completed a quantitative interview in 2008. The AUDIT was used to characterize hazardous alcohol use. Multivariate logistic regression was used to determine independent associations of demographic and HIV risk variables with hazardous alcohol use (vs. non-hazardous). Results Forty percent of our sample met criteria for hazardous alcohol use. Variables independently associated with hazardous drinking were reporting any sexually transmitted infection (STI), having sex with a FSW while under the influence of alcohol, being younger than 36 years of age, living in Tijuana, and ever having been jailed. Hazardous drinkers were less likely ever to have been deported or to have shared injection drugs. Discussion and Conclusions Hazardous alcohol use is associated with HIV risk, including engaging in sex with FSWs while intoxicated and having an STI among male clients of FSWs in Tijuana. Scientific Significance We systematically described patterns and correlates of hazardous alcohol use among male clients of FSWs in Tijuana, Mexico. The results suggest that HIV/STI risk reduction interventions must target hazardous alcohol users, and be tailored to address alcohol use. PMID:25066863

  18. Prenatal exposure to dexamethasone disturbs sex-determining gene expression and fetal testosterone production in male embryos.

    PubMed

    Yun, Hyo Jung; Lee, Ji-Yeon; Kim, Myoung Hee

    2016-02-26

    Prenatal stress is known to cause intrauterine fetal growth retardation, and is also associated with various long-term effects in the form of metabolic and neurodevelopmental diseases in adults. Many of the diseases associated with prenatal stress exhibit a sex bias. Perturbations and vulnerability to prenatal stress are often more profound in males, but the mechanisms responsible for this relationship are not clear. We have previously shown that administration of the synthetic glucocorticoid, dexamethasone (Dex), at embryonic days 7.5, 8.5, and 9.5, induces embryonic growth restriction in a sex-dependent manner in a mouse model. Here we examined the effect of prenatal exposure to Dex on gonadal development. During male gonadal development, sex-determining genes, such as Sry, Sox9, and other downstream genes, were found to be dysregulated in response to prenatal Dex, whereas the genes for the ovarian pathway were affected to a lesser degree in females. In addition, fetal testosterone concentrations were decreased by prenatal exposure to Dex, in parallel with reduced numbers of 3?-hydroxysteroid dehydrogenase (3?-HSD)-positive cells in the embryonic testis. These results show that prenatal exposure to Dex differentially influences male versus female on the gene expression and hormone production during sex determination. We believe these studies provide valuable insights into possible mechanisms responsible for sex-specific responses to prenatal stress. PMID:26827828

  19. 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; Stlting, 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

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

    SciTech Connect

    Vikram, A.; Tripathi, D.N.; Ramarao, P.; Jena, G.B.

    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.

  1. Have Sex Differences in Spatial Ability Evolved from Male Competition for Mating and Female Concern for Survival?

    ERIC Educational Resources Information Center

    Ecuyer-Dab, Isabelle; Robert, Michele

    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…

  2. A Case Study of the Academic Achievement of African American Males in Single-Sex Classrooms in Rural South Carolina

    ERIC Educational Resources Information Center

    Pannell, Lynette Martin

    2013-01-01

    The purpose of this study was to investigate the differences of Measures of Academic Progress (MAP) scores between fourth-grade African American male students who were enrolled in single-sex classrooms and their counterparts who were enrolled in coeducational classrooms. The research provided descriptive data concerning one Title I school in rural

  3. “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

  4. A Case Study of the Academic Achievement of African American Males in Single-Sex Classrooms in Rural South Carolina

    ERIC Educational Resources Information Center

    Pannell, Lynette Martin

    2013-01-01

    The purpose of this study was to investigate the differences of Measures of Academic Progress (MAP) scores between fourth-grade African American male students who were enrolled in single-sex classrooms and their counterparts who were enrolled in coeducational classrooms. The research provided descriptive data concerning one Title I school in rural…

  5. 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

  6. Have Sex Differences in Spatial Ability Evolved from Male Competition for Mating and Female Concern for Survival?

    ERIC Educational Resources Information Center

    Ecuyer-Dab, Isabelle; Robert, Michele

    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

  7. 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…

  8. Male-only care and classical polyandry in birds: phylogeny, ecology and sex differences in remating opportunities.

    PubMed Central

    Owens, Ian P F

    2002-01-01

    It has been argued recently that the combination of male-only parental care and classical polyandry in birds is the most interesting and yet the least understood of all avian breeding systems. Despite a huge number of hypotheses, careful comparative analyses have repeatedly failed to identify consistent ecological differences between species showing male-only care and closely related species showing other patterns of care. This has led to the suggestion that such analyses fail because the crucial differences are between ancient lineages rather than between closely related species. Here, therefore, I use comparisons between families to test three well-known hypotheses: that male-only care is associated with: (i) a low rate of fecundity; (ii) large egg size relative to female size; or (iii) female-biased opportunities for remating. Families showing male-only care do not differ from families showing female-only care with respect to rate of fecundity or relative egg size. There is, however, a significant difference between these two groups of families with respect to an index of remating opportunities, nesting density. Families showing female-only care nest at high density, while those showing male-only care nest at very low density. This is one of the first times a consistent ecological correlate has been identified for male-only care in birds. It suggests that female-only care arises (or persists) in families where remating opportunities are abundant for both sexes, whereas male-only care arises (or persists) in families where remating opportunities are rare for both sexes and particularly scarce for males. This in turn suggests that sex differences in remating opportunities are the key ecological factor in determining male-only care and classical polyandry in birds. PMID:11958697

  9. 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 Central

    Grov, Christian; Rendina, H. Jonathon; Ventuneac, Ana; Parsons, Jeffrey T.

    2014-01-01

    N=147 MSM completed time-line follow-back interviews about the venues where they met their male partners (n=1,180 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 to meeting a partner at a gay bar/club (AOR=.44), online (AOR=.42), bathhouse (AOR=.35), or via “other” venues (AOR=.35), all p < .01. These findings highlight the need to develop innovative HIV/STI prevention initiatives for men who attend sex parties. PMID:25226209

  10. 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

  11. Wolbachia is not all about sex: male-feminizing Wolbachia alters the leafhopper Zyginidia pullula transcriptome in a mainly sex-independent manner

    PubMed Central

    Asgharian, Hosseinali; Chang, Peter L.; Mazzoglio, Peter J.; Negri, Ilaria

    2014-01-01

    Wolbachia causes the feminization of chromosomally male embryos in several species of crustaceans and insects, including the leafhopper Zyginidia pullula. In contrast to the relatively well-established ecological aspects of male feminization (e.g., sex ratio distortion and its consequences), the underlying molecular mechanisms remain understudied and unclear. We embarked on an exploratory study to investigate the extent and nature of Wolbachia's effect on gene expression pattern in Z. pullula. We sequenced whole transcriptomes from Wolbachia-infected and uninfected adults. 18147 loci were assembled de novo, including homologs of several Drosophila sex determination genes. A number of transcripts were flagged as candidate Wolbachia sequences. Despite the resemblance of Wolbachia-infected chromosomal males to uninfected and infected chromosomal females in terms of sexual morphology and behavior, principal component analysis revealed that gene expression patterns did not follow these sexual phenotype categories. The principal components generated by differentially expressed genes specified a strong sex-independent Wolbachia effect, followed by a weaker Wolbachia-sexual karyotype interaction effect. Approaches to further examine the molecular mechanism of Wolbachia-host interactions have been suggested based on the presented findings. PMID:25225494

  12. 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; GrandMaison, 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

  13. Changing seasonality and phenological responses of free-living male arctic ground squirrels: the importance of sex

    PubMed Central

    Sheriff, Michael J.; Richter, Melanie M.; Buck, C. Loren; Barnes, Brian M.

    2013-01-01

    Many studies have addressed the effects of climate change on species as a whole; however, few have examined the possibility of sex-specific differences. To understand better the impact that changing patterns of snow-cover have on an important resident Arctic mammal, we investigated the long-term (13 years) phenology of hibernating male arctic ground squirrels living at two nearby sites in northern Alaska that experience significantly different snow-cover regimes. Previously, we demonstrated that snow-cover influences the timing of phenological events in females. Our results here suggest that the end of heterothermy in males is influenced by soil temperature and an endogenous circannual clock, but timing of male emergence from hibernation is influenced by the timing of female emergence. Males at both sites, Atigun and Toolik, end heterothermy on the same date in spring, but remain in their burrows while undergoing reproductive maturation. However, at Atigun, where snowmelt and female emergence occur relatively early, males emerge 8 days earlier than those at Toolik, maintaining a 12-day period between male and female emergence found at each site, but reducing the pre-emergence euthermic period that is critical for reproductive maturation. This sensitivity in timing of male emergence to female emergence will need to be matched by phase shifts in the circannual clock and responsiveness to environmental factors that time the end of heterothermy, if synchrony in reproductive readiness between the sexes is to be preserved in a rapidly changing climate. PMID:23836786

  14. Sex hormone receptors in the hypothalamus and their role in sexual differentiation of the male rat brain

    SciTech Connect

    Shishkina, I.V.; Babichev, V.N.; Ozol', L.Yu.

    1986-09-01

    In this investigation, changes in the level of receptors for sex hormones in the hypothalamus and cerebral cortex of male rats were studied on the first through fifth days of postnatal life, and the results obtained were compared with the levels of luteinizing hormone and sex hormones in the peripheral blood in order to discover any correlation between these parameters. 2,4,6,7,-/sup 3/H-estradiol-17..beta.. and 1,2,6,7-/sup 3/H-testosterone were used as labeled hormones. The values of the association constant and concentration of specific binding sites for estradiol and testosterone in hypothalamus and cerebral cortex of male rats during neonatal development is shown. It is found that in male rats on the first day after birth, receptors for estradiol and testosterone are present and they enable the action both of the testicular hormone and that of estradiol to be realized.

  15. Molecular Identification of XY Sex-Reversed Female and YY Male Channel Catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production of channel catfish leads U.S. aquaculture, and monosex culture may provide higher production efficiencies. Determination of phenotypic sex is labor intensive and not practical for large scale culture. Catfish have an X-Y sex determination system with monomorphic sex chromosomes. Hormonal...

  16. Sex differences in liver toxicity-do female and male human primary hepatocytes react differently to toxicants in vitro?

    PubMed

    Mennecozzi, Milena; Landesmann, Brigitte; Palosaari, Taina; Harris, Georgina; Whelan, Maurice

    2015-01-01

    There is increasing amount of evidence for sex variation in drug efficiency and toxicity profiles. Women are more susceptible than men to acute liver injury from xenobiotics. In general, this is attributed to sex differences at a physiological level as well as differences in pharmacokinetics and pharmacodynamics, but neither of these can give a sufficient explanation for the diverse responses to xenobiotics. Existing data are mainly based on animal models and limited data exist on in vitro sex differences relevant to humans. To date, male and female human hepatocytes have not yet been compared in terms of their responses to hepatotoxic drugs. We investigated whether sex-specific differences in acute hepatotoxicity can be observed in vitro by comparing hepatotoxic drug effects in male and female primary human hepatocytes. Significant sex-related differences were found for certain parameters and individual drugs, showing an overall higher sensitivity of female primary hepatocytes to hepatotoxicants. Moreover, our work demonstrated that high content screening is feasible with pooled primary human hepatocytes in suspension. PMID:25849576

  17. Sex Differences in Liver Toxicity—Do Female and Male Human Primary Hepatocytes React Differently to Toxicants In Vitro?

    PubMed Central

    Mennecozzi, Milena; Landesmann, Brigitte; Palosaari, Taina; Harris, Georgina; Whelan, Maurice

    2015-01-01

    There is increasing amount of evidence for sex variation in drug efficiency and toxicity profiles. Women are more susceptible than men to acute liver injury from xenobiotics. In general, this is attributed to sex differences at a physiological level as well as differences in pharmacokinetics and pharmacodynamics, but neither of these can give a sufficient explanation for the diverse responses to xenobiotics. Existing data are mainly based on animal models and limited data exist on in vitro sex differences relevant to humans. To date, male and female human hepatocytes have not yet been compared in terms of their responses to hepatotoxic drugs. We investigated whether sex-specific differences in acute hepatotoxicity can be observed in vitro by comparing hepatotoxic drug effects in male and female primary human hepatocytes. Significant sex-related differences were found for certain parameters and individual drugs, showing an overall higher sensitivity of female primary hepatocytes to hepatotoxicants. Moreover, our work demonstrated that high content screening is feasible with pooled primary human hepatocytes in suspension. PMID:25849576

  18. Neonatal testosterone partially organizes sex differences in stress-induced emotionality in mice

    PubMed Central

    Seney, Marianne L.; Walsh, Christopher; Stolakis, Ryan; Sibille, Etienne

    2012-01-01

    Major depressive disorder (MDD) is a debilitating disorder of altered mood regulation. Despite well established sex differences in MDD prevalence, the mechanism underlying the increased female vulnerability remains unknown. Although evidence suggests an influence of adult circulating hormone levels on mood (i.e. activational effects of hormones), MDD prevalence is consistently higher in women across life stages (and therefore hormonal states), suggesting that additional underlying structural or biological differences place women at higher risk. Studies in human subjects and in rodent models suggest a developmental origin for mood disorders, and interestingly, a developmental process also establishes sex differences in the brain. Hence, based on these parallel developmental trajectories, we hypothesized that a proportion of the female higher vulnerability to MDD may originate from the differential organization of mood regulatory neural networks early in life (i.e. organizational effects of hormones). To test this hypothesis in a rodent system, we took advantage of a well-established technique used in the field of sexual differentiation (neonatal injection with testosterone) to masculinize sexually dimorphic brain regions in female mice. We then investigated adult behavioral consequences relating to emotionality by comparing neonatal testosterone-treated females to normal males and females. Under baseline/trait conditions, neonatal testosterone treatment of female mice did not influence adult emotionality, but masculinized adult locomotor activity, as revealed by the activational actions of hormones. Conversely, the increased vulnerability of female mice to develop high emotionality following unpredictable chronic mild stress (UCMS) was partially masculinized by neonatal testosterone exposure, with no effect on post-UCMS locomotion. The elevated female UCMS-induced vulnerability did not differ between adult hormone treated groups. These results demonstrate that sex differences in adult emotionality in mice are partially caused by the organizational effects of sex hormones during development, hence supporting a developmental hypothesis of the human adult female prevalence of MDD. PMID:22394611

  19. Prevalence of Same-Sex Sexual Behavior and Associated Characteristics among Low-Income Urban Males in Peru

    PubMed Central

    Clark, Jesse L.; Caceres, Carlos F.; Lescano, Andres G.; Konda, Kelika A.; Leon, Segundo R.; Jones, Franca R.; Kegeles, Susan M.; Klausner, Jeffrey D.; Coates, Thomas J.

    2007-01-01

    Background Peru has a concentrated HIV epidemic in which men who have sex with men are particularly vulnerable. We describe the lifetime prevalence of same-sex sexual contact and associated risk behaviors of men in Peru's general population, regardless of their sexual identity. Methods and Results A probability sample of males from low-income households in three Peruvian cities completed an epidemiologic survey addressing their sexual risk behavior, including sex with other men. Serum was tested for HSV-2, HIV, and syphilis. Urine was tested for chlamydia and gonorrhea. A total of 2,271 18–30 year old men and women were contacted, of whom 1,645 (72.4%) agreed to participate in the study. Among the sexually experienced men surveyed, 15.2% (85/558, 95% CI: 12.2%–18.2%) reported a history of sex with other men. Men ever reporting sex with men (MESM) had a lower educational level, had greater numbers of sex partners, and were more likely to engage in risk behaviors including unprotected sex with casual partners, paying for or providing compensated sex, and using illegal drugs. MESM were also more likely to have had previous STI symptoms or a prior STI diagnosis, and had a greater prevalence of HSV-2 seropositivity. Conclusions Many low-income Peruvian men have engaged in same-sex sexual contact and maintain greater behavioral and biological risk factors for HIV/STI transmission than non-MESM. Improved surveillance strategies for HIV and STIs among MESM are necessary to better understand the epidemiology of HIV in Latin America and to prevent its further spread. PMID:17712426

  20. Sex-Dependent Antipsychotic Capacity of 17β-Estradiol in the Latent Inhibition Model: A Typical Antipsychotic Drug in Both Sexes, Atypical Antipsychotic Drug in Males

    PubMed Central

    Arad, Michal; Weiner, Ina

    2010-01-01

    The estrogen hypothesis of schizophrenia suggests that estrogen is a natural neuroprotector in women and that exogenous estrogen may have antipsychotic potential, but results of clinical studies have been inconsistent. We have recently shown using the latent inhibition (LI) model of schizophrenia that 17β-estradiol exerts antipsychotic activity in ovariectomized (OVX) rats. The present study sought to extend the characterization of the antipsychotic action of 17β-estradiol (10, 50 and 150 μg/kg) by testing its capacity to reverse amphetamine- and MK-801-induced LI aberrations in gonadally intact female and male rats. No-drug controls of both sexes showed LI, ie, reduced efficacy of a previously non-reinforced stimulus to gain behavioral control when paired with reinforcement, if conditioned with two but not five tone-shock pairings. In both sexes, amphetamine (1 mg/kg) and MK-801 (50 μg/kg) produced disruption (under weak conditioning) and persistence (under strong conditioning) of LI, modeling positive and negative/cognitive symptoms, respectively. 17β-estradiol at 50 and 150 μg/kg potentiated LI under strong conditioning and reversed amphetamine-induced LI disruption in both males and females, mimicking the action of typical and atypical antipsychotic drugs (APDs) in the LI model. 17β-estradiol also reversed MK-induced persistent LI, an effect mimicking atypical APDs and NMDA receptor enhancers, but this effect was observed in males and OVX females but not in intact females. These findings indicate that in the LI model, 17β-estradiol exerts a clear-cut antipsychotic activity in both sexes and, remarkably, is more efficacious in males and OVX females where it also exerts activity considered predictive of anti-negative/cognitive symptoms. PMID:20613719

  1. Prenatal Testosterone Induces Sex-Specific Dysfunction in Endothelium-Dependent Relaxation Pathways in Adult Male and Female Rats1

    PubMed Central

    Chinnathambi, Vijayakumar; Yallampalli, Chandrasekhar; Sathishkumar, Kunju

    2013-01-01

    ABSTRACT Prenatal testosterone (T) exposure impacts postnatal cardiovascular function, leading to increases in blood pressure with associated decreased endothelium-dependent vascular relaxation in adult females. Endothelial function in males is not known. Furthermore, which of the endothelial pathways contributes to endothelial dysfunction and if there exists sex differences are not known. The objective of this study was to characterize the relative contribution of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF) to the impaired endothelium-dependent vasodilation in prenatal T-exposed adult males and females. Offspring of pregnant rats treated with T propionate or its vehicle were examined. Telemetric blood pressure levels and endothelium-dependent vascular reactivity were assessed with wire myography. Levels of nitric oxide synthase (NOS3) and Kcnn3 and Kcnn4 channel expression were examined in mesenteric arteries. Mean arterial pressure was significantly higher in T males and females than in controls. Endothelium-dependent acetylcholine relaxation was significantly lower in both T males and females. EDHF-mediated relaxation was specifically blunted in T males (Emax = 48.64% 3.73%) compared to that in control males (Emax = 81.71% 3.18%); however, NO-mediated relaxation was specifically impaired in T females (Emax = 36.01% 4.29%) compared with that in control females (Emax = 54.56% 6.37%). Relaxation to sodium nitroprusside and levcromakalim were unaffected with T-treatment. NOS3 protein was decreased in T females but not in T males. Kcnn3 expression was decreased in both T males and females compared to controls. These findings suggest that prenatal T leads to an increase in blood pressure in the adult offspring, associated with blunting of endothelial cell-associated relaxation and that the effects are sex-specific: EDHF-related in males and NO-related in females. PMID:23966325

  2. Sensilla on different organs of female and male Telenomus dendrolimusi Chu (Hymenoptera: Scelionidae).

    PubMed

    Zhang, Sufang; Zhang, Zhen; Kong, Xiangbo; Wang, Hongbin; Luo, Jitong; Yang, Zhongwu

    2015-11-01

    Telenomus dendrolimusi Chu is a dominant egg parasitoid of Dendrolimus, which is the most serious conifer defoliator in China. However, the host locating mechanism of T. dendrolimusi is unclear. To take better advantage of this kind of parasitoid, it is necessary to clarify the basic knowledge of the organization of the wasp's sensory system. In this study, the external morphologies of the sensilla on the entire female and male T. dendrolimusi body were described using scanning electron microscopy. Antennae shape and sensilla types were sexually dimorphic. Ten segments and nine types of sensilla were found on the female antenna, including basiconic sensillum (BS), chaeticum sensillum (ChS), trichoid sensillum type 1 (TS1), trichoid sensillum type 2 (TS2), trichoid curvata sensillum (TCS), sickle-shaped sensillum (SSS), multiporous gustatory sensillum (MGS), campaniform sensillum (CS), and styloconica sensillum (STS). The distribution of the sensilla was directional on female antenna. The male antenna consisted of 12 segments, and 1-3 segments were similar to those of the female. Five types of sensilla were found on male antenna, including BS, ChS, TS1, TCS, and STS. The mouthparts, thoracic legs, eyes, mesonotum, and wings were all covered with longitudinally fluted TSs without hole. A tympana structure appeared on the thoracic legs. Special crevice-shaped structures were found on the abdomens of both T. dendrolimusi sexes. Possible sensilla functions are discussed according to their morphology. These results provide a solid basis for further researches about the parasitic mechanisms of T. dendrolimusi. PMID:26499312

  3. Identification of pheromone-like compounds in male reproductive organs of the oriental locust Locusta migratoria.

    PubMed

    Ban, Liping; Napolitano, Elio; Serra, Andrea; Zhou, Xianhong; Iovinella, Immacolata; Pelosi, Paolo

    2013-08-01

    Despite the great economical interest of locusts in agriculture, knowledge on their chemoreception systems is still poor. Phenylacetonitrile is recognised as a pheromone of the desert locust Schistocerca gregaria, triggering gregarization, promoting aggregation and inhibiting courtship. However, in the other major locust species, Locusta migratoria, pheromones have not been reported. We have identified the two isomers of naphthylpropionitrile from the male reproductive organs of L. migratoria. Chemical synthesis has confirmed the identity of the two compounds. Both isomers show significant affinity to CSP91, a protein reported in the testis, but not to three other proteins of the same family (CSP180, CSP540 and CSP884) expressed in female accessory glands. The striking similarity of these compounds with phenylacetonitrile and the unusual nature of such chemicals strongly suggest that naphthylpropionitrile could be pheromones for L. migratoria, while their site of expression and binding activity indicate a role in communication between sexes. PMID:23867828

  4. Sex pheromone blend discrimination by male moths fromE andZ strains of European corn borer.

    PubMed

    Glover, T J; Tang, X H; Roelofs, W L

    1987-01-01

    Sex pheromone behavioral responses were analyzed in a flight tunnel with European corn borer,Ostrinia nubilalis (Hbner), males from three distinct populations. Males from a bivoltine and a univoltine biotype using a 97.8?2.2 blend (Z strains) of (Z)- and (E)-11-tetradecenyl acetate were assayed with treatments containing 0, 0.5, 1, and 3% of theE isomer. Males from neither population oriented in the plume to the 100%Z treatment, but bivoltine males oriented and flew to the source to the other three treatments, whereas univoltine males oriented and flew to the source only to the 1 % and 3 %E treatments. Males from a bivoltine biotype using a 1?99 blend ofZ/E isomers (E strain) were assayed with sources containing 0, 0.5, 1, and 3% of theZ isomer. Males did not orient to the 0%Z source, but oriented and flew to the source to the other three treatments. In addition to using opposite geometric isomers for the main pheromone component, the bivoltineE strain differed from the bivoltineZ strain by producing and responding better to 1 % of the minor component and by storing 3 times more pheromone in the female glands. Contrary to previous reports, the blend of two pheromone components is significantly better than the main component alone in eliciting oriented flight and close-range behavior with males from all three populations of European corn borer. PMID:24301366

  5. 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 ...

  6. The association between substance use and intimate partner violence within Black male same-sex relationships.

    PubMed

    Wu, Elwin; El-Bassel, Nabila; McVinney, L Donald; Hess, Leona; Fopeano, Mark V; Hwang, Hyesung G; Charania, Mahnaz; Mansergh, Gordon

    2015-03-01

    Compared with the extant research on heterosexual intimate partner violence (IPV)-including the knowledge base on alcohol and illicit drug use as predictors of such IPV-there is a paucity of studies on IPV among men who have sex with men (MSM), especially Black MSM. This study investigates the prevalence of experiencing and perpetrating IPV among a sample of Black MSM couples and examines whether heavy drinking and/or illicit substance use is associated with IPV. We conducted a secondary analysis on a data set from 74 individuals (constituting 37 Black MSM couples) screened for inclusion in a couple-based HIV prevention pilot study targeting methamphetamine-involved couples. More than one third (n= 28, 38%) reported IPV at some point with the current partner: 24 both experiencing and perpetrating, 2 experiencing only, and 2 perpetrating only. IPV in the past 30 days was reported by 21 (28%) of the participants: 18 both experiencing and perpetrating, 1 experiencing only, and 2 perpetrating only. Heavy drinking and methamphetamine use each was associated significantly with experiencing and perpetrating IPV throughout the relationship as well as in the past 30 days. Rock/crack cocaine use was significantly associated with any history of experiencing and perpetrating IPV. Altogether, IPV rates in this sample of Black MSM couples equal or exceed those observed among women victimized by male partners as well as the general population of MSM. This exploratory study points to a critical need for further efforts to understand and address IPV among Black MSM. Similar to heterosexual IPV, results point to alcohol and illicit drug use treatment as important avenues to improve the health and social well-being of Black MSM. PMID:24919997

  7. Sex Determination in Bees. II. Additivity of Maleness Genes in APIS MELLIFERA

    PubMed Central

    Chaud-Netto, Jos

    1975-01-01

    Twenty-two randomly taken morphological characters were used in order to estimate the Mahalanobis generalized distance between diploid males, diploid workers, haploid males and triploid workers. It was found that adult diploid males are metamales and triploid females are slightly masculinized. These facts indicate that the maleness genes are slightly additive. PMID:1132678

  8. Psychosexual and social-cognitive correlates of sexual risk behavior among male clients of female sex workers in Tijuana, Mexico

    PubMed Central

    Semple, Shirley J.; Strathdee, Steffanie A.; Gallardo Cruz, Manuel; Robertson, Angela; Goldenberg, Shira; Patterson, Thomas L.

    2011-01-01

    Male clients of female sex workers (FSWs) may act as a bridge to the general population contributing to the spread of HIV and other sexually transmitted infections in the United States and Mexico. This study used cross-sectional data to identify psychosexual and social cognitive factors associated with sexual risk behavior in a bi-national sample of 300 male clients of FSWs recruited in Tijuana, Mexico from June to October, 2008. In a multiple regression analysis, the number of unprotected vaginal sex acts with FSWs was associated with higher sexual compulsivity scores, lower self-efficacy for condom use, greater use of illicit drugs, and more financial need. Behavioral interventions are urgently needed to assist clients of FSWs in reducing high-risk behaviors in an effort to prevent the spread of HIV/STIs in this high-risk population and their sexual partners. PMID:21154035

  9. HIV and associated risk factors among male clients of female sex workers in a Chinese border region

    PubMed Central

    Reilly, Kathleen H.; Wang, Junjie; Zhu, Zhibin; Li, Shuanghe; Yang, Tinghua; Ding, Guowei; Qian, Han-Zhu; Kissinger, Patricia; Wang, Ning

    2012-01-01

    Background Male clients of female sex workers (FSWs) serve as a potential bridge of HIV to the general population. Little is known about the characteristics and risk factors for HIV infection among male clients patronizing FSWs in Hekou County, Yunnan Province in southern China bordering with Vietnam. Methods Male clients were recruited through outreach of study staff, referrals by Vietnamese FSWs, their bosses, and snowball sampling. Each participant completed a questionnaire survey and donated a blood specimen to test for HIV, herpes simplex virus type 2 (HSV-2), and syphilis. Logistic regression models were fitted to identify factors associated with HIV infection. Results Among 306 participants, 28 (9.2%) were HIV positive, 81 (26.5%) were HSV-2 positive, and none were infected with syphilis. Approximately half (n=149, 49.2%) reported always using condoms with sex workers in the past year; 36 (11.8%) reported a history of injection drug use (IDU). Compared to HIV negative men, HIV positive men were more likely to have a history of IDU (64.3% vs. 6.5%) and be co-infected with HSV-2 (50.0% vs. 24.1%). Conclusions IDU was the most salient risk factor for HIV infection in this study, which suggests that male clients may acquire HIV from routes other than commercial sex, but the significance of HSV-2 infection indicates that sexual transmission is also of concern. HIV prevention intervention programs for this often ignored and hard-to-reach risk group should be two-pronged, addressing both drug use and commercial sex. PMID:23007705

  10. Factors Contributing to the Enrollment of Males in Program Areas Not Traditional for Their Sex at the Secondary Vocational Education Level in Ohio.

    ERIC Educational Resources Information Center

    Knight, James A.; And Others

    This research was conducted to identify factors contributing to the enrollment of male high school students in Ohio in program areas nontraditional for their sex. Using the 1980 Executive Student Follow-up Report, 28 vocational education programs not traditional for males in Ohio (less than 20 percent male enrollment) were identified, and the top

  11. Male biased sex ratio in the Mediterranean fruit fly Ceratitis capitata, an example of Y-chromosome meiotic drive.

    PubMed

    Shahjahan, R M; Rendon, P A; Cook, L M; Wood, R J

    2006-06-01

    A case of Y-chromosome meiotic drive is reported in the Mediterranean fruit fly Ceratitis capitata. It arose in an irradiated male and results in excess of males. Male excess is inherited strictly from father to son. A Y-linked factor MP (male producer) is proposed. Higher drive can be selected, but distortion declines rapidly in the absence of selection. Hybrid males from crosses between driving males and nondriving females also show drive but to a reduced extent, suggesting the action of suppressors. Sex ratio distortion is independent of postzygotic mortality, and is not associated with an obvious chromosome arrangement. Spermiogenesis in driving males is characterised by abnormalities in sperm tails and reduced numbers in some sperm cysts, whereas neighbouring cysts of the same MP testis are essentially wild type. The average number of missing sperms plus deformed sperms approximates to the average depression in female recovery among the progenies of siblings, suggesting that most of the missing or abnormal sperms would have given rise to females, that is, they would have been X-bearing. To explain the heterogeneity between neighbouring cysts, a theory is proposed that links it to variation in X-chromosome sensitivity to MP, arising by random suppression of the genetic basis of sensitivity during the six mitotic divisions in the origin of the cyst from its stem cell before meiosis. PMID:16598189

  12. How the Male Body Works Sexually

    MedlinePLUS

    ... shows the male sex organs. The role of testosterone Testosterone is the main male hormone. It causes the ... to develop, and promotes erections and sexual behavior. Testosterone also causes secondary sexual characteristics at puberty, such ...

  13. Male only progeny in Anastrepha suspensa by RNAi-induced sex reversion of chromosomal females

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Tephritidae sex determination is established by orthologs to the Drosophila melanogaster transformer and transformer-2 genes. In contrast, primary signals for sex determination are different in these species corresponding to the number of X chromosomes (XSE) in Drosophilidae species and to the pr...

  14. The Effects of Sex and Gender Role Orientation on Mentorship in Male-Dominated Occupations.

    ERIC Educational Resources Information Center

    Scandura, Terri A.; Ragins, Belle Rose

    1993-01-01

    Responses from 608 certified public accountants who had mentors showed that biological sex was not related to mentoring, but gender role orientation was. Those with androgynous sex role orientation reported more mentoring functions than did those with masculine or feminine orientations. (SK)

  15. Epigenetics and sex-specific fitness: an experimental test using male-limited evolution in Drosophila melanogaster.

    PubMed

    Abbott, Jessica K; Innocenti, Paolo; Chippindale, Adam K; Morrow, Edward H

    2013-01-01

    When males and females have different fitness optima for the same trait but share loci, intralocus sexual conflict is likely to occur. Epigenetic mechanisms such as genomic imprinting (in which expression is altered according to parent-of-origin) and sex-specific maternal effects have been suggested as ways by which this conflict can be resolved. However these ideas have not yet been empirically tested. We designed an experimental evolution protocol in Drosophila melanogaster that enabled us to look for epigenetic effects on the X-chromosome-a hotspot for sexually antagonistic loci. We used special compound-X females to enforce father-to-son transmission of the X-chromosome for many generations, and compared fitness and gene expression levels between Control males, males with a Control X-chromosome that had undergone one generation of father-son transmission, and males with an X-chromosome that had undergone many generations of father-son transmission. Fitness differences were dramatic, with experimentally-evolved males approximately 20% greater than controls, and with males inheriting a non-evolved X from their father about 20% lower than controls. These data are consistent with both strong intralocus sexual conflict and misimprinting of the X-chromosome under paternal inheritance. However, expression differences suggested that reduced fitness under paternal X inheritance was largely due to deleterious maternal effects. Our data confirm the sexually-antagonistic nature of Drosophila's X-chromosome and suggest that the response to male-limited X-chromosome evolution entails compensatory evolution for maternal effects, and perhaps modification of other epigenetic effects via coevolution of the sex chromosomes. PMID:23922998

  16. Severe impairment of male reproductive organ development in a low SMN expressing mouse model of spinal muscular atrophy.

    PubMed

    Ottesen, Eric W; Howell, Matthew D; Singh, Natalia N; Seo, Joonbae; Whitley, Elizabeth M; Singh, Ravindra N

    2016-01-01

    Spinal muscular atrophy (SMA) is caused by low levels of survival motor neuron (SMN), a multifunctional protein essential for higher eukaryotes. While SMN is one of the most scrutinized proteins associated with neurodegeneration, its gender-specific role in vertebrates remains unknown. We utilized a mild SMA model (C/C model) to examine the impact of low SMN on growth and development of mammalian sex organs. We show impaired testis development, degenerated seminiferous tubules, reduced sperm count and low fertility in C/C males, but no overt sex organ phenotype in C/C females. Underscoring an increased requirement for SMN expression, wild type testis showed extremely high levels of SMN protein compared to other tissues. Our results revealed severe perturbations in pathways critical to C/C male reproductive organ development and function, including steroid biosynthesis, apoptosis, and spermatogenesis. Consistent with enhanced apoptosis in seminiferous tubules of C/C testes, we recorded a drastic increase in cells with DNA fragmentation. SMN was expressed at high levels in adult C/C testis due to an adult-specific splicing switch, but could not compensate for low levels during early testicular development. Our findings uncover novel hallmarks of SMA disease progression and link SMN to general male infertility. PMID:26830971

  17. Severe impairment of male reproductive organ development in a low SMN expressing mouse model of spinal muscular atrophy

    PubMed Central

    Ottesen, Eric W.; Howell, Matthew D.; Singh, Natalia N.; Seo, Joonbae; Whitley, Elizabeth M.; Singh, Ravindra N.

    2016-01-01

    Spinal muscular atrophy (SMA) is caused by low levels of survival motor neuron (SMN), a multifunctional protein essential for higher eukaryotes. While SMN is one of the most scrutinized proteins associated with neurodegeneration, its gender-specific role in vertebrates remains unknown. We utilized a mild SMA model (C/C model) to examine the impact of low SMN on growth and development of mammalian sex organs. We show impaired testis development, degenerated seminiferous tubules, reduced sperm count and low fertility in C/C males, but no overt sex organ phenotype in C/C females. Underscoring an increased requirement for SMN expression, wild type testis showed extremely high levels of SMN protein compared to other tissues. Our results revealed severe perturbations in pathways critical to C/C male reproductive organ development and function, including steroid biosynthesis, apoptosis, and spermatogenesis. Consistent with enhanced apoptosis in seminiferous tubules of C/C testes, we recorded a drastic increase in cells with DNA fragmentation. SMN was expressed at high levels in adult C/C testis due to an adult-specific splicing switch, but could not compensate for low levels during early testicular development. Our findings uncover novel hallmarks of SMA disease progression and link SMN to general male infertility. PMID:26830971

  18. Argyrophilic nucleolar organizing region associated protein synthesis in hair root cells of humans at different developmental stages and sex.

    PubMed

    Eroz, R; Yilmaz, S; Cucer, N

    2013-07-01

    Argyrophilic nucleolar organizing region (AgNORs) associated proteins are important for cell proliferation and various diseases. We investigated AgNOR protein synthesis in hair root cells of males and females at different ages using two-dimensional image analysis. Experiments were performed on 58 healthy male and 24 healthy female volunteers in three groups according to age and sex. Hair root cells obtained from hair follicles were stained with silver. Total AgNOR number/total nuclear number (TAN/TNN) and total AgNOR area/nuclear area (TAA/NA) for each nucleus were analyzed. The only significant difference was observed in TAA/NA values for males and females from 6 to 12 years old. We suggest that the difference is due to high NOR activity caused by increased growth hormone production in hair root cells. PMID:23480229

  19. Transgression and the Situated Body: Gender, Sex, and the Gay Male Teacher.

    ERIC Educational Resources Information Center

    Rofes, Eric

    This paper begins by examining representations of gay male school teachers in discourses produced by gay men, illustrating the ways gay men represent themselves in public discourse. The literature is reviewed for answers to questions about the role of the gay male teacher in education and the responsibility of the gay male teacher to gay…

  20. 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, Gran; 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

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

    PubMed Central

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

    2015-01-01

    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

  2. Variations in cerebral organization as a function of handedness, hand posture in writing, and sex.

    PubMed

    Levy, J; Reid, M

    1978-06-01

    During the past century, it has become increasingly apparent that there is a great deal of variation in the direction and degree of cerebral lateralization, a plurality of people having language and related functions strongly specialized to the left hemisphere and visuospatial functions strongly specialized to the right, with substantial minorities manifesting various deviations from this pattern. In particular, in 35%-50% of sinistrals and 1%-10% of dextrals, the right hemisphere is specialized for linguistic skills, and in some unknown fraction of the two handedness groups, verbal and/or spatial abilities are, to varying extents, bilateralized. Levy (1973) suggested that the hand posture adopted during writing might be an index of the lateral relationship between the dominant writing hand and the language hemisphere, a normal posture indicating contralateral language specialization, and an inverted posture indicating ipsilateral language specialization. In the present investigation, two tachistoscopic tests of cerebral lateralization, one measuring spatial functions and one measuring verbal function, were administered to 73 subjects classified by handedness, hand posture during writing, and sex. Among both dextral and sinistral subjects with a normal writing posture, language and spatial functions were specialized to the contralateral and ipsilateral hemispheres, respectively, and lateral differentiation of the brain was strong. The reverse was seen in subjects having an inverted writing posture. In all groups, females were less laterally differentiated than males. In 70 out of 73 subjects, the direction of cerebral laterization was accurately predicted by handedness and hand posture. The 3 subjects (2 females and 1 male) who failed to manifest the predicted relations were all left-handers having an inverted hand posture . In this group, lateral differentiation was so weak that the reliability of the tachistoscopic tests was reduced, and we attribute these three predictive failures to this cause. Thus, almost all of the variation in the lateral organization of the brain was accounted for by handedness, hand posture, and sex. PMID:670905

  3. 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, Gnter 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

  4. A male-killing Wolbachia carries a feminizing factor and is associated with degradation of the sex-determining system of its host.

    PubMed

    Sugimoto, Takafumi N; Ishikawa, Yukio

    2012-06-23

    Endosymbiotic bacteria of the genus Wolbachia induce diverse reproductive alterations in their insect hosts. Wolbachia (wSca) infecting the moth Ostrinia scapulalis causes unusual male killing, in which males (genotype: ZZ) selectively die during embryonic and larval development, whereas females (genotype: ZW), in turn, selectively die when cured of infection. To gain insight into the interaction between wSca and the host, we analysed phenotypic and genetic sexes of the embryos and larvae of normal, wSca-infected, and infected-and-cured O. scapulalis by diagnosing the sex-specifically spliced transcripts of Osdsx-a homologue of the sex-determining gene doublesex-and sex chromatin in interphase nuclei, respectively. It was observed that the female-type Osdsx was expressed in the infected male (ZZ) progenies destined to die, whereas the male-type Osdsx was expressed in the cured female (ZW) progenies destined to die. These findings suggest that (i) wSca, a male killer, carries a genetic factor that feminizes the male host, (ii) the sex-determining system of the host is degraded, and (iii) a mismatch between the genetic and phenotypic sexes underlies the sex-specific death. PMID:22219393

  5. Role of sex hormones in hypercapnia-induced activation of the locus coeruleus in female and male rats.

    PubMed

    de Carvalho, D; Marques, D A; Bernuci, M P; Leite, C M; Araújo-Lopes, R; Anselmo-Franci, J; Bícego, K C; Szawka, R E; Gargaglioni, L H

    2016-01-28

    The locus coeruleus (LC) has been suggested as a CO2 chemoreceptor site in mammals. Most of the studies involving the role of the LC in hypercapnic ventilatory responses have been performed in males. Since ovarian steroids modulate the activity of LC neurons and females have a different respiratory response to CO2 than males, we evaluated the activity of LC noradrenergic neurons during normocapnia and hypercapnia in female and male rats with distinct sex hormone levels. Ovariectomized (OVX), estradiol (E2)-treated ovariectomized (OVX+E2) and female rats on the diestrous day of the estrous cycle were evaluated. Concurrently, males were investigated as gonad-intact, orchidectomized (ORX), testosterone (T)-treated ORX (ORX+T), and E2-treated ORX (ORX+E2). Activation of LC neurons was determined by double-label immunohistochemistry to c-Fos and tyrosine hydroxylase (TH). Hypercapnia induced by 7% CO2 increased the number of c-Fos/TH-immunoreactive (ir) neurons in the LC of all groups when compared to air exposure. Hypercapnia-induced c-Fos expression did not differ between diestrous females and intact male rats. In the OVX+E2 group, there was attenuation in the c-Fos expression during normocapnia compared with OVX rats, but CO2 responsiveness was not altered. Moreover, in ORX rats, neither T nor E2 treatments changed c-Fos expression in LC noradrenergic neurons. Thus, in female rats, E2 reduces activation of LC noradrenergic neurons, whereas in males, sex hormones do not influence the LC activity. PMID:26601772

  6. Role of the male specific lethal (msl) genes in modifying the effects of sex chromosomal dosage in Drosophila.

    PubMed Central

    Bhadra, U; Pal-Bhadra, M; Birchler, J A

    1999-01-01

    Immunostaining of chromosomes shows that the male-specific lethal (MSL) proteins are associated with all female chromosomes at a low level but are sequestered to the X chromosome in males. Histone-4 Lys-16 acetylation follows a similar pattern in normal males and females, being higher on the X and lower on the autosomes in males than in females. However, the staining pattern of acetylation and the mof gene product, a putative histone acetylase, in msl mutant males returns to a uniform genome-wide distribution as found in females. Gene expression on the autosomes correlates with the level of histone-4 acetylation. With minor exceptions, the expression levels of X-linked genes are maintained with either an increase or decrease of acetylation, suggesting that the MSL complex renders gene activity unresponsive to H4Lys16 acetylation. Evidence was also found for the presence of nucleation sites for association of the MSL proteins with the X chromosome rather than individual gene binding sequences. We suggest that sequestration of the MSL proteins occurs in males to nullify on the autosomes and maintain on the X, an inverse effect produced by negatively acting dosage-dependent regulatory genes as a consequence of the evolution of the X/Y sex chromosomal system. PMID:10224258

  7. Tricks of the trade: sexual health behaviors, the context of HIV risk, and potential prevention intervention strategies for male sex workers.

    PubMed

    Reisner, Sari L; Mimiaga, Matthew J; Mayer, Kenneth H; Tinsley, Jake P; Safren, Steven A

    2008-01-01

    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. Participants reported an average of 46 male sex partners in the prior 12 months; 31% of participants were HIV-infected. Male sex workers frequently used substances during sex and had elevated levels of psychological distress. Qualitative findings suggest that trauma-informed mental health and substance abuse treatment, ready access to HIV/STI testing and treatment and condoms/informational materials, support groups to address isolation/loneliness, skill-building for risk reduction with sex partners, and paid incentives as add-ons to effective behavior change interventions may be valuable intervention components. Targeting consumers of paid/exchanged sex may assist with changing community norms regarding the practice of transactional sex. Multipronged interventions to decrease sexual risk taking among male sex workers would also benefit from addressing the unique socioeconomic and legal needs of this population. PMID:19928046

  8. A Reasoned Action Model of Male Client Involvement in Commercial Sex Work in Kibera, A Large Informal Settlement in Nairobi, Kenya

    PubMed Central

    Roth, Eric Abella; Ngugi, Elizabeth; Benoit, Cecilia; Jansson, Mikael; Hallgrimsdottir, Helga

    2015-01-01

    Male clients of female sex workers (FSWs) are epidemiologically important because they can form bridge groups linking high- and low-risk subpopulations. However, because male clients are hard to locate, they are not frequently studied. Recent research emphasizes searching for high-risk behavior groups in locales where new sexual partnerships form and the threat of HIV transmission is high. Sub-Saharan Africa public drinking venues satisfy these criteria. Accordingly, this study developed and implemented a rapid assessment methodology to survey men in bars throughout the large informal settlement of Kibera, Nairobi, Kenya, with the goal of delineating cultural and economic rationales associated with male participation in commercial sex. The study sample consisted of 220 male patrons of 110 bars located throughout Kiberas 11 communities. Logistic regression analysis incorporating a modified Reasoned Action Model indicated that a social norm condoning commercial sex among male peers and the cultural belief that men should practice sex before marriage support commercial sex involvement. Conversely, lacking money to drink and/or pay for sexual services were barriers to male commercial sex involvement. Results are interpreted in light of possible harm reduction programs focusing on FSWs male clients. PMID:26778847

  9. An Analysis of State Guidelines for Sex Education Instruction in Public Schools and a Review of Exemplary Sex Education Programs for Teenagers Offered by Nonschool Organizations.

    ERIC Educational Resources Information Center

    Kirby, Douglas; Scales, Peter

    1981-01-01

    Two articles studying state guidelines for sex education show that states in general weakly support sex education, and strongly support local autonomy and parent involvement. Guidelines do not show many regional differences. Also reviews exemplary sex education programs offered by nonschool organizations. (JAC)

  10. It's all about sex: male-female differences in lung development and disease

    PubMed Central

    Carey, Michelle A.; Card, Jeffrey W.; Voltz, James W.; Arbes, Samuel J.; Germolec, Dori R.; Korach, Kenneth S.; Zeldin, Darryl C.

    2008-01-01

    Accumulating evidence suggests that gender impacts the incidence, susceptibility and severity of several lung diseases. Gender also influences lung development and physiology. Data from both human and animal studies suggests that sex hormones may contribute to disease pathogenesis or serve as protective factors, depending on the disease involved. In this review, the influence of gender and sex hormones on lung development and pathology will be discussed, with specific emphasis on pulmonary fibrosis, asthma and cancer. PMID:17764971

  11. 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

  12. 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

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

    PubMed

    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 anti sociality.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 anti sociality. Nevertheless, in convicted sexual offenders anti sociality, sexual preoccupation (like hypersexuality), and pedophilic interest are important predictors of sexual reoffending against prepubescent children.Therefore, 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 [corrected]. PMID:26147099

  14. 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.

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

    PubMed

    Cunha, F S; Domenice, S; Cmara, V L; Sircili, M H P; Gooren, L J G; Mendona, 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-administration 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

  16. 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…

  17. 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

  18. Sex differences in brain organization: implications for human communication.

    PubMed

    Hanske-Petitpierre, V; Chen, A C

    1985-12-01

    This article reviews current knowledge in two major research domains: sex differences in neuropsychophysiology, and in human communication. An attempt was made to integrate knowledge from several areas of brain research with human communication and to clarify how such a cooperative effort may be beneficial to both fields of study. By combining findings from the area of brain research, a communication paradigm was developed which contends that brain-related sex differences may reside largely in the area of communication of emotion. PMID:3912348

  19. Development of systemic lupus erythematosus in a male-to-female transsexual: the role of sex hormones revisited.

    PubMed

    Chan, K L; Mok, C C

    2013-11-01

    Systemic lupus erythematosus (SLE) predominantly affects women of childbearing age. The infrequency of SLE in men and disease onset in prepubertal or postmenopausal women suggests a role of estrogen in the predisposition to the disease. Patients with hypergonadotrophic hypogonadism are prone to the development of SLE, and the use of exogenous estrogens in women increases the relative risk of SLE onset and disease flares. These observations provide indirect evidence for an opposite role of estrogens and androgens in the pathogenesis of SLE. We report on a male-to-female transsexual who developed SLE 20 years after sex-reassignment surgery and prolonged estrogen therapy. The role of sex hormones in SLE is revisited. PMID:23897544

  20. 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,

  1. Birth Order and Sibling Sex Ratio in Homosexual Male Adolescents and Probably Prehomosexual Feminine Boys.

    ERIC Educational Resources Information Center

    Blanchard, Ray; And Others

    1995-01-01

    Examined the hypothesis that male homosexuals have a greater than average proportion of male siblings and a later than average birth order, by comparing a group of prehomosexual boys (individuals exhibiting cross-gender behaviors) and homosexual adolescents with a control group. Both predicted results were confirmed. (MDM)

  2. 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 Central

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

    2013-01-01

    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 four 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

  3. Same-sex cohabitation under the effects of quinpirole induces a conditioned socio-sexual partner preference in males, but not in female rats.

    PubMed

    Triana-Del Rio, Rodrigo; Montero-Domnguez, Felix; Cibrian-Llanderal, Tamara; Tecamachaltzi-Silvaran, Miriam B; Garcia, Luis I; Manzo, Jorge; Hernandez, Mara Elena; Coria-Avila, Genaro A

    2011-10-01

    The effects of the dopamine D2-type receptor agonist quinpirole (QNP) were examined on the development of conditioned same-sex partner preference induced by cohabitation in rats. In Experiment 1, males received either saline or QNP (1.25mg/kg) and cohabited during three trials with almond-scented stimulus males that were sexually nave. In Experiment 2, males received six trials, and in Experiment 3 received three trials with sexually expert stimulus males. During a final drug-free preference test, males chose between the familiar or a novel male partner. In Experiments 1, 2 and 3 only QNP-treated males displayed a social preference for the familiar male, observed with more time spent together. In Experiment 3 males also displayed a sexual preference observed with more non-contact erections when were exposed to their male partner. In Experiment 4 we tested the effects on OVX, E+P primed females that received 1 systemic injection of either saline or QNP during three conditioning trials. In Experiment 5, females received 2 injections 12-h apart during each trial. Results indicated that both saline and QNP-treated females failed to develop partner preference. These data demonstrate that enhanced D2-type receptor activity during cohabitation facilitates the development of conditioned same-sex partner preference in males, but not in female rats. We discuss the implications for same-sex partner preferences. PMID:21704064

  4. 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

  5. The Effect of Resistant Soybean on Male and Female Development and Adult Sex Ratios of Heterodera glycines.

    PubMed

    Colgrove, A L; Niblack, T L

    2005-06-01

    To determine whether currently used sources of resistance (soybean Plant Introductions [PI] 548402, 88788, 90763, 437654, 209332, 89772, and 548316) influence sex ratios in H. glycines, four inbred lines of the nematode characterized by zero or high numbers of females on resistant soybean were used to observe the number of adult males produced. Nematodes were allowed to infect soybean roots for 5 days in pasteurized sand. Infected plants were washed and transferred to hydroponic culture tubes. Males were collected every 2 to 3 days up to 30 days after infestation (DAI), and females were collected at 30 DAI. Resistance that suppressed adult females also altered adult male numbers. On PI 548402, 90763, and 437654, male numbers were low and close to zero, whereas on PI 88788, male numbers were higher (alpha = 0.05). In a separate experiment, the same PIs were infected by an inbred line that tested as an HG Type 0 (i.e., the numbers of females that developed on each PI were less than 10% of the number that developed on the standard susceptible soybean cultivar Lee). In this experiment, male numbers were similar to female numbers on PI 548402, 90763, 437654, and 89772, whereas male numbers on PI 88788, 209332, and 548316 were higher than those of females (alpha = 0.05). In all experiments, the total number of adults that developed to maturity relative to the number of second-stage juveniles that initially penetrated the root was less on resistant than on susceptible soybean (P

  6. No evidence for increased extinction proneness with decreasing effective population size in a parasitoid with complementary sex determination and fertile diploid males

    PubMed Central

    2010-01-01

    Background In species with single locus complementary sex determination (sl-CSD), the sex of individuals depends on their genotype at one single locus with multiple alleles. Haploid individuals are always males. Diploid individuals are females when heterozygous, but males when homozygous at the sex-determining locus. Diploid males are typically unviable or effectively sterile, hence imposing a genetic load on populations. Diploid males are produced from matings of partners that share an allele at the sex-determining locus. The lower the allelic diversity at the sex-determining locus, the more diploid males are produced, ultimately impairing the growth of populations and jeopardizing their persistence. The gregarious endoparasitoid wasp Cotesia glomerata is one of only two known species with sl-CSD and fertile diploid males. Results By manipulating the relatedness of the founders, we established replicated experimental populations of the parasitoid C. glomerata differing in their genetic effective size, and thus in allelic richness at the sex-determining locus and in the expected magnitude of diploid male production. Our long-term survey of population welfare and persistence did not provide evidence for increased proneness to population extinction with decreasing initial genetic effective population size. Most recorded surrogates of fitness nevertheless decayed over time and most experimental populations eventually went extinct, suggesting that the negative effects of inbreeding outweighed any premium from the fertility of diploid males. Conclusions The fertility of diploid males may have evolved as an adaptation prompted by the risk of extinction looming over small isolated populations of species with sl-CSD. However, fertility of diploid males does not negate the costs imposed by their production, and although it may temporarily stave off extinction, it is not sufficient to eradicate the negative effects of inbreeding. PMID:21110868

  7. Frequency of Sexual Activity With Most Recent Male Partner Among Young, Internet-Using Men Who Have Sex With Men in the United States

    PubMed Central

    WALL, KRISTIN M.; STEPHENSON, ROBERT; SULLIVAN, PATRICK S.

    2015-01-01

    Sex frequency, defined here as the number of oral or anal sex acts with the most recent partner in the past year, is a potential driver of risk for sexually transmitted infections. However, few data on sex frequency have been reported for men who have sex with men (MSM). Data from an Internet survey of MSM were used to describe sex frequency with most recent main and casual male partners and to estimate factors associated with higher sex frequency. Among 5,193 MSM, higher sex frequency was associated with younger age, shorter relationship duration, and reporting a main (vs. casual) partner; and lower sex frequency with male partners was associated with heterosexual or bisexual (vs. homosexual) identity or Black race (vs. non-Hispanic White). Secondary analyses of estimates of sex frequency from 2 publicly available nationally representative datasets comprised of primarily heterosexual survey respondents (the 2008 General Social Survey and the 1992 National Health and Social Life Survey) were performed. Sex frequency among MSM respondents was similar to that reported by heterosexuals. PMID:24059971

  8. 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.)

  9. 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

  10. Male sex pheromones and the phylogeographic structure of the Lutzomyia longipalpis species complex (Diptera: Psychodidae) from Brazil and Venezuela.

    PubMed

    Watts, Phillip C; Hamilton, J Gordon C; Ward, Richard D; Noyes, Harry A; Souza, Nataly A; Kemp, Stephen J; Feliciangeli, M Dora; Brazil, Reginaldo; Maingon, Rhayza D C

    2005-10-01

    Lutzomyia longipalpis, a sibling complex, is the main vector of Leishmania chagasi/infantum. Discriminating between siblings is important as they may differ in vectorial capacity. Lutzomyia longipalpis populations display distinct male sex pheromone chemotypes. We investigated the phylogeographic pattern of variation at microsatellite loci from 11 populations from Brazil and Venezuela related to their male pheromone. Temporal genetic differentiation was mostly not significant at the same site. Spatial genetic differentiation was, however, strong, although there was only a weak relationship between genetic differentiation and the geographic distance separating the samples (r2 < 0.10); geographic separation explained a much greater (54-97%) percentage of the genetic differences among populations when samples with the same pheromone type were analyzed separately. A cluster analysis showed five groups: Lu. cruzi (Brazil) and Lu. pseudolongipalpis (Venezuela) as separate species, two (mostly 9-methyl-germacrene-B) Venezuelan and Brazilian groups, and a very distinct cluster of Brazilian cembrene populations. PMID:16222018

  11. Annual changes in plasma levels of cortisol and sex steroid hormones in male rainbow trout, Oncorhynchus mykiss

    NASA Astrophysics Data System (ADS)

    Hou, Ya-Yi; Han, Xiao-Dong; Suzuki, Yuzuru

    2001-09-01

    The profiles of cortisol, testosterone, 11-ketotestosterone and 17α, 20β-dihydroxy-4-pregnene-3-one in male rainbow trout reared under constant water temperature and natural photoperiod were determined by radioimmunoassay. Gonads of male rainbow trout reached maturity when the fish were two years old. Changes in the plasma levels of both sex steroid hormones and cortisol were closely related to the GSI. Plasma levels of testosterone, 11-ketotestosterone and 17α; 20β-dihydroxy 4-pregnene-3-one showed a clear peak in the annual breeding season, when the GSI reached their maxima. Plasma cortisol levels also showed clearly seasonal changes in both two- and three-year-old fish. The results suggest that the elevated plasma levels of cortisol may not just be due to stresses during the breeding season but have certain physiological functions in the reproduction of rainbow trout.

  12. Opposite-sex housing reactivates the declining GnRH system in aged transgenic male mice with FGF signaling deficiency

    PubMed Central

    Chung, Wilson C. J.; Hayes, Tyrone B.; Tsai, Pei-San

    2012-01-01

    The continued presence of gonadotropin-releasing hormone (GnRH) neurons is required for a healthy reproductive lifespan, but factors that maintain postnatal GnRH neurons have not been identified. To begin to understand these factors, we investigated whether 1) fibroblast growth factor (FGF) signaling and 2) interactions with the opposite sex are involved in the maintenance of the postnatal GnRH system. A transgenic mouse model (dnFGFR mouse) with the targeted expression of a dominant-negative FGF receptor (dnFGFR) in GnRH neurons was used to examine the consequence of FGF signaling deficiency on postnatal GnRH neurons. Male dnFGFR mice suffered a significant loss of postnatal GnRH neurons within the first 100 days of life. Interestingly, this loss was reversed after cohabitation with female, but not male, mice for 300550 days. Along with a rescue in GnRH neuron numbers, opposite-sex housing in dnFGFR males also increased hypothalamic GnRH peptide levels, promoted a more mature GnRH neuronal morphology, facilitated litter production, and enhanced testicular morphology. Last, mice hypomorphic for FGFR3 exhibited a similar pattern of postnatal GnRH neuronal loss as dnFGFR males, suggesting FGF signaling acts, in part, through FGFR3 to enhance the maintenance of the postnatal GnRH system. In summary, we have shown that FGF signaling is required for the continued presence of postnatal GnRH neurons. However, this requirement is not absolute, since sexual interactions can compensate for defects in FGFR signaling, thereby rescuing the declining GnRH system. This suggests the postnatal GnRH system is highly plastic and capable of responding to environmental stimuli throughout adult life. PMID:23047985

  13. The male-produced sex pheromone of the true bug, Phthia picta, is an unusual hydrocarbon.

    PubMed

    Soldi, Rafael A; Rodrigues, Mauro A C M; Aldrich, Jeffrey R; Zarbin, Paulo H G

    2012-07-01

    Phthia picta is part of a complex of true bugs (Heteroptera) in Brazil that attack tomatoes, being particularly damaging because nymphs and adults feed on both leaves and fruit. Gas chromatography (GC) of aeration extracts of adult males vs. females revealed the presence of a male-specific compound. GC-electroantennographic detector experiments indicated that the antennae of females are highly sensitive to this male-specific compound. GC-mass spectrometry and GC-FTIR analyses suggested a methyl branched hydrocarbon structure for this compound. After synthesis of three different proposed structures, the natural product was indentified as 5,9,17-trimethylhenicosane, which was strongly attractive to females in Y-tube olfactometer bioassays. Analysis of dissected body parts of adults revealed that the pheromone is produced in the lateral accessory glands of the metathoracic scent gland of males only. PMID:22723201

  14. Expression patterns of sex-determination genes in single male and female embryos of two Bactrocera fruit fly species during early development.

    PubMed

    Morrow, J L; Riegler, M; Frommer, M; Shearman, D C A

    2014-12-01

    In tephritids, the sex-determination pathway follows the sex-specific splicing of transformer (tra) mRNA, and the cooperation of tra and transformer-2 (tra-2) to effect the sex-specific splicing of doublesex (dsx), the genetic double-switch responsible for male or female somatic development. The Dominant Male Determiner (M) is the primary signal that controls this pathway. M, as yet uncharacterized, is Y-chromosome linked, expressed in the zygote and directly or indirectly diminishes active TRA protein in male embryos. Here we first demonstrated the high conservation of tra, tra-2 and dsx in two Australian tephritids, Bactrocera tryoni and Bactrocera jarvisi. We then used quantitative reverse transcription PCR on single, sexed embryos to examine expression of the key sex-determination genes during early embryogenesis. Individual embryos were sexed using molecular markers located on the B.?jarvisi?Y-chromosome that was also introgressed into a B.?tryoni line. In B.?jarvisi, sex-specific expression of tra transcripts occurred between 3 to 6?h after egg laying, and the dsx isoform was established by 7?h. These milestones were delayed in B.?tryoni lines. The results provide a time frame for transcriptomic analyses to identify M and its direct targets, plus information on genes that may be targeted for the development of male-only lines for pest management. PMID:25116961

  15. Synchronous firing of antennal-lobe projection neurons encodes the behaviorally effective ratio of sex-pheromone components in male Manduca sexta

    PubMed Central

    Martin, Joshua P.; Lei, Hong; Riffell, Jeffrey A.; Hildebrand, John G.

    2013-01-01

    Olfactory stimuli that are essential to an animal's survival and reproduction are often complex mixtures of volatile organic compounds in characteristic proportions. Here, we investigated how these proportions are encoded in the primary olfactory processing center, the antennal lobe (AL), of male Manduca sexta moths. Two key components of the female's sex pheromone, present in an approximately 2:1 ratio, are processed in each of two neighboring glomeruli in the macroglomerular complex (MGC) of males of this species. In wind-tunnel flight experiments, males exhibited behavioral selectivity for ratios approximating the ratio released by conspecific females. The ratio between components was poorly represented, however, in the firing-rate output of uniglomerular MGC projection neurons (PNs). PN firing rate was mostly insensitive to the ratio between components, and individual PNs did not exhibit a preference for a particular ratio. Recording simultaneously from pairs of PNs in the same glomerulus, we found that the natural ratio between components elicited the most synchronous spikes, and altering the proportion of either component decreased the proportion of synchronous spikes. The degree of synchronous firing between PNs in the same glomerulus thus selectively encodes the natural ratio that most effectively evokes the natural behavioral response to pheromone. PMID:24002682

  16. Inactivation or non-reactivation: what accounts better for the silence of sex chromosomes during mammalian male meiosis?

    PubMed

    Page, Jess; de la Fuente, Roberto; Manterola, Marcia; Parra, Mara Teresa; Viera, Alberto; Berros, Soledad; Fernndez-Donoso, Ral; Rufas, Julio S

    2012-06-01

    During the first meiotic prophase in male mammals, sex chromosomes undergo a program of transcriptional silencing called meiotic sex chromosome inactivation (MSCI). MSCI is triggered by accumulation of proteins like BRCA1, ATR, and ?H2AX on unsynapsed chromosomes, followed by local changes on the sex chromatin, including histone modifications, incorporation of specific histone variants, non-histone proteins, and RNAs. It is generally thought that MSCI represents the transition of unsynapsed chromatin from a transcriptionally active state to a repressed state. However, transcription is generally low in the whole nucleus during the early stages of the first meiotic prophase, when markers of MSCI first appear, and is then reactivated globally during pachytene. Thus, an alternative possibility is that MSCI represents the targeted maintenance and/or reinforcement of a prior repressed state, i.e., a failure to reactivate. Here, we present an analysis of the temporal and spatial appearance of transcriptional and MSCI markers, as well as chromatin modifications related to transcriptional regulation. We show that levels of RNA pol II and histone H3 acetylated at lysine 9 (H3K9ac) are low during leptotene, zygotene, and early pachytene, but increase strongly in mid-pachytene, indicating that reactivation occurs with some delay after synapsis. However, while transcription markers appear abundantly on the autosomes at mid-pachytene, they are not directed to the sex chromosomes. Interestingly, we found that chromatin modifications related to transcriptional silencing and/or MSCI, namely, histone H3 trimethylated at lysine 9 (H3K9me3), histone H3 monomethylated at lysine 4 (H3K4me1), ?H2AX, SUMO1, and XMR, appear on the sex chromosomes before autosomes become reactivated. These results suggest that the onset of MSCI during late zygotene and early pachytene may prevent sex chromosome reactivation during mid-pachytene instead of promoting inactivation de novo. Additionally, we found temporal differences between the X and Y chromosomes in the recruitment of DNA repair and MSCI markers, indicating a differential regulation of these processes. We propose that many of the meiotic defects attributed to failure to silence sex chromosomes could be interpreted as a more general process of transcriptional misregulation that occurs under certain pathological circumstances in zygotene and early pachytene. PMID:22366883

  17. Perceptions about HIV and condoms and consistent condom use among male clients of commercial sex workers in the Philippines.

    PubMed

    Regan, Rotrease; Morisky, Donald E

    2013-04-01

    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 knowledge and condom attitudes affect condom use among male clients of FSWs in the Philippines, the main objective was to determine what characteristics (age, education, HIV knowledge, marital status) as well as attributes taken from protection motivation theory (perceived vulnerability, perceived severity, response efficacy) are significantly associated with consistent condom use among male clients of FSWs. Logistic regression analyses showed that the odds of using condoms consistently with an FSW are 13% higher for those with more years of education (adjusted odds ratio [AOR] = 1.13; 95% confidence interval [CI] = 1.03, 1.23), higher versus lower perception of severity of HIV/AIDS (AOR = 1.97; 95% CI = 1.04, 3.73), and had a higher score for response efficacy of condoms (AOR = 1.14; 95% CI = 1.03, 1.27). Future HIV/AIDS prevention interventions that address condom use among male clients should promote educational attainment and focus on awareness of the enduring negative health consequences of acquiring HIV/AIDS, as well as cultivate positive attitudes toward the efficacy of condom use, using creative social marketing strategies. PMID:22773598

  18. Isolation of a Female-Emitted Sex Pheromone Component of the Fungus Gnat, Lycoriella ingenua, Attractive to Males.

    PubMed

    Andreadis, Stefanos S; Cloonan, Kevin R; Myrick, Andrew J; Chen, Haibin; Baker, Thomas C

    2015-12-01

    Lycoriella ingenua Dufour (Diptera: Sciaridae) is acknowledged as the major pest species of the white button mushroom, Agaricus bisporus, throughout the world. Components of the female-produced sex pheromone of this species were identified previously as C15-C18 n-alkanes, with the major component n-heptadecane, and shown to be attractive to L. mali. However, a subsequent report could not repeat this work. We reinvestigated the sex pheromone of this species by confirming that virgin females were attractive to males in a Y-tube bioassay and by collection of extracts from virgin females. Extracts were analyzed by gas chromatography coupled to electroantennographic detection, and by the less widely-used technique of gas chromatography coupled to a behavioral bioassay to detect compounds causing wing-fanning and copulatory abdomen curling in males. A single, behaviorally-active pheromone component was isolated and characterized by gas chromatography coupled to mass spectrometry. This component was definitively not n-heptadecane or any of the other C15-C19 n-alkanes reported previously, but is proposed to be a sesquiterpene alcohol having analytical characteristics that closely matched those of reference germacradienols. PMID:26585193

  19. Factors associated with treatment acceptance and compliance among incarcerated male sex offenders.

    PubMed

    Clegg, Carl; Fremouw, William; Horacek, Thomas; Cole, Angel; Schwartz, Rebecca

    2011-09-01

    The files of sex offenders who had been offered treatment at a medium-security state prison were divided into three groups: treatment refusal (n = 59), treatment noncompliance (n = 61), and treatment compliance (n = 36). Demographic, offense-related, clinical, and psychological assessment data were collected. Significant differences were found between groups on years to parole eligibility; plea; relation to victim; childhood sexual victimization; and Minnesota Multiphasic Personality Inventory-2 Variable Response Inconsistency (VRIN), Lie (L), and Masculinity-Femininity (Mf) scale scores. Logistic regression analyses revealed that significant predictors of treatment refusal include increased time until parole eligibility and lower VRIN and Mf scores (vs. noncompliant) as well as no history of childhood sexual victimization and higher L scores (vs. compliant). Having entered a not-guilty plea was the only significant predictor of noncompliance among those who initially accepted treatment. These findings are discussed in relation to previous studies of sex offender treatment compliance and directions for future research. PMID:20622252

  20. Is the rate of insertion and deletion mutation male biased?: Molecular evolutionary analysis of avian and primate sex chromosome sequences.

    PubMed Central

    Sundstrm, Hannah; Webster, Matthew T; Ellegren, Hans

    2003-01-01

    The rate of mutation for nucleotide substitution is generally higher among males than among females, likely owing to the larger number of DNA replications in spermatogenesis than in oogenesis. For insertion and deletion (indel) mutations, data from a few human genetic disease loci indicate that the two sexes may mutate at similar rates, possibly because such mutations arise in connection with meiotic crossing over. To address origin- and sex-specific rates of indel mutation we have conducted the first large-scale molecular evolutionary analysis of indels in noncoding DNA sequences from sex chromosomes. The rates are similar on the X and Y chromosomes of primates but about twice as high on the avian Z chromosome as on the W chromosome. The fact that indels are not uncommon on the nonrecombining Y and W chromosomes excludes meiotic crossing over as the main cause of indel mutation. On the other hand, the similar rates on X and Y indicate that the number of DNA replications (higher for Y than for X) is also not the main factor. Our observations are therefore consistent with a role of both DNA replication and recombination in the generation of short insertion and deletion mutations. A significant excess of deletion compared to insertion events is observed on the avian W chromosome, consistent with gradual DNA loss on a nonrecombining chromosome. PMID:12750337

  1. Administration of estradiol benzoate before insemination could skew secondary sex ratio toward males in Holstein dairy cows.

    PubMed

    Emadi, S R; Rezaei, A; Bolourchi, M; Hovareshti, P; Akbarinejad, V

    2014-07-01

    The present study was conducted to investigate the effect of estradiol benzoate administration before insemination on secondary sex ratio (proportion of male calves at birth) in Holstein dairy cows. Cows (n = 1,647) were randomly assigned to 2 experimental groups by parity over a 1-yr period. Cows in the control group (n = 827; 232 primiparous and 595 multiparous cows) received 2 administrations of PGF2? (500?g) 14d apart, started at 30 to 35d postpartum. Twelve d after the second PGF2? injection, cows received GnRH (100?g), followed by administration of PGF2? 7d later. Cows in the treatment group (n = 820; 238 primiparous and 582 multiparous cows) received the same hormonal administrations as the cows in the control group. Additionally, cows in the treatment group received estradiol benzoate (1mg) 1 d after the third PGF2? injection. Estrus detection by visual observation was started 1 d after the third PGF2? injection and after estradiol administration in the control (for 6d) and treatment (for 36h) groups, respectively. Artificial insemination was carried out 12h after observation of standing estrus. Exposure of cows to heat stress at conception was determined based on temperature-humidity index. Estrus detection rate was lower in primiparous than in multiparous cows (P < 0.05), but conception rate was higher in primiparous vs multiparous cows (P < 0.05). Estradiol administration improved estrus detection rate and fertility (P < 0.05); moreover, it increased secondary sex ratio (adjusted odds ratio: 1.645; P = 0.017). Exposure to heat stress diminished heat detection rate and fertility (P < 0.05), and altered secondary sex ratio toward males (adjusted odds ratio: 2.863; P = 0.012). In conclusion, the present study revealed that estradiol administration before insemination could improve fertility and increase the probability of calves being male in Holstein dairy cows. Moreover, the results showed that cows exposed to heat stress around conception had diminished fertility and increased secondary sex ratio. PMID:24906936

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

    PubMed

    Valentova, Jaroslava Varella; Stulp, Gert; T?ebick, Vt; Havl?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

  3. 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

  4. Preferred and Actual Relative Height among Homosexual Male Partners Vary with Preferred Dominance and Sex Role

    PubMed Central

    Valentova, Jaroslava Varella; Stulp, Gert; T?ebick, Vt; Havl?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 participants 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

  5. 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

  6. 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

  7. Structural composition of myocardial infarction scar in middle-aged male and female rats: does sex matter?

    PubMed

    Bogatyryov, Yevgen; Tomanek, Robert J; Dedkov, Eduard I

    2013-11-01

    The present study was designed to determine whether the structural composition of the scar in middle-aged post-myocardial infraction (MI) rats is affected by the biological sex of the animals. A large MI was induced in 12-month-old male (M-MI) and female (F-MI) Sprague-Dawley rats by ligation of the left coronary artery. Four weeks after the MI, rats with transmural infarctions, greater than 50% of the left ventricular (LV) free wall, were evaluated. The extent of LV remodeling and fractional volumes of fibrillar collagen (FC), myofibroblasts, vascular smooth muscle (SM) cells, and surviving cardiac myocytes (CM) in the scars were compared between the two sexes. The left ventricle of post-MI male and female rats underwent a similar degree of remodeling as evidenced by the analogous scar thinning ratio (0.46 0.02 vs. 0.42 0.05) and infarct expansion index (1.06 0.07 vs. 1.12 0.08), respectively. Most important, the contents of major structural components of the scar revealed no evident difference between M-MI and F-MI rats (interstitial FC, 80.74 2.08 vs. 82.57 4.53; myofibroblasts, 9.59 1.68 vs.9.56 1.15; vascular SM cells, 2.27 0.51 vs. 3.38 0.47; and surviving CM, 3.26 0.39 vs. 3.05 0.38, respectively). Our data are the first to demonstrate that biological sex does not influence the structural composition of a mature scar in middle-aged post-MI rats. PMID:23867842

  8. Assisting gay men to maintain safer sex: an evaluation of an AIDS service organization's safer sex maintenance program.

    PubMed

    Miller, R L

    1995-01-01

    As the second decade of the AIDS crisis unfolds, increasing concern has been raised that the widespread adoption of condom use that occurred among gay men in the 1980s is not being maintained. Most interventions to promote condom use among gay men are delivered by community-based organizations via programs that are virtually undocumented; little is known about their effectiveness, or the processes by which they may work. This study describes safer sex practices among self-identified gay men following their participation in an intervention developed and implemented by a community-based organization. The intervention was designed to enhance men's attitudes, beliefs, and self-efficacy expectations to maintain safer sex. Among 150 men with complete data at both assessments, self-reported condom use was low. Men reported using condoms more consistently for anal sexual behavior than oral sexual behavior, but there were men who reported consistent unprotected anal sexual intercourse. The intervention had little impact on patterns of behavior over time, although desired changes in attitudes, beliefs, and self-efficacy expectations were evidenced following the intervention. The results suggest the importance of assisting community-based organizations to document program models. Findings also suggest that community-based organizations can develop interventions to successfully enhance factors that theoretically support maintenance of safer sexual behaviors. PMID:8664098

  9. 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

  10. Heterogeneity of characteristics, structure, and dynamics of male and hijra sex workers in selected cities of Pakistan

    PubMed Central

    Thompson, Laura H; Salim, Momina; Baloch, Chaker Riaz; Musa, Nighat; Reza, Tahira; Dar, Nosheen; Arian, Shahzad; Blanchard, James F; Emmanuel, Faran

    2013-01-01

    Background We sought to describe the characteristics and operational dynamics of male sex workers (MSW) and hijra sex workers (HSWs) in 11 cities across Pakistan in 2011. Methods We report descriptive statistics of self-reported sexual behaviour data from cross-sectional mapping and biological and behavioural surveys conducted among 1431 MSWs and 1415 HSWs in four cities across Pakistan in 2011. Results While Karachi had the largest numbers of MSWs and HSWs, Quetta had the largest relative population sizes, with 3.6?MSWs per 1000 male adults and 3.3?HSWs per 1000 male adults. There was considerable variability in the proportion of HSWs who operate through deras, ranging from 2.2% in Peshawar to 62.7% in Karachi. The number of HSWs per guru varies by city, from 1.5 in Quetta to 16.5?HSWs per guru in Karachi. Among HSWs, the use of mobile phones for solicitation ranged from 37.6% in Quetta to 83% in Peshawar and among MSWs the use of mobile phones ranged from 27% in Karachi to 52% in Quetta. In Quetta, a large proportion of HSWs (41%) find clients through gurus. Client volume tended to be higher among HSWs and among both MSWs and HSWs in Quetta and Peshawar. Condom use with clients was most consistent in Quetta, with 31% of MSWs and 41% of HSWs reporting always using condoms with clients. Peshawar had the greatest proportion reporting never using condoms. Conclusions There is considerable geographic heterogeneity in the characteristics and operational dynamics of MSWs and HSWs across Pakistan. PMID:23605854

  11. The Effects of Single-Sex Mathematics Classrooms on African American Males in the Ninth Grade

    ERIC Educational Resources Information Center

    Faulkner-Simmons, Denise

    2012-01-01

    Research indicated that educators must consider socio-ecological accommodations because not all students learn in cooperative groups. Students must be taught how to discover the process of learning and to apply knowledge to real life situations. Gurian and Ballew (2003) identified differences in the male and female brain and the differences in how

  12. The Effects of Single-Sex Mathematics Classrooms on African American Males in the Ninth Grade

    ERIC Educational Resources Information Center

    Faulkner-Simmons, Denise

    2012-01-01

    Research indicated that educators must consider socio-ecological accommodations because not all students learn in cooperative groups. Students must be taught how to discover the process of learning and to apply knowledge to real life situations. Gurian and Ballew (2003) identified differences in the male and female brain and the differences in how…

  13. Behavior Treatment of Deviant Sex-Role Behaviors in a Male Child.

    ERIC Educational Resources Information Center

    Rekers, George A.; And Others

    This study demonstrated reinforcement control over pronounced feminine behaviors in a male child who had been psychologically evaluated as manifesting "childhood cross-gender identity." Reinforcement control over cross-gender behavior was demonstrated by identifying some behavioral treatment conditions under which feminine behaviors could be

  14. Reactions of Male Raters to Interviewee Self-Presentation Style and Sex: Extensions of Previous Research.

    ERIC Educational Resources Information Center

    Dipboye, Robert L.; Wiley, Jack W.

    1978-01-01

    In an earlier experiment, college recruiters evaluated a videotape of an interviewee who was either male or female, and who displayed either a moderately aggressive or passive self-presentation. In the present paper, two studies are presented which replicate and extend the findings of the original experiment. (Author)

  15. Opinion: Sex, Gender and the Diagnosis of Autism--A Biosocial View of the Male Preponderance

    ERIC Educational Resources Information Center

    Goldman, Sylvie

    2013-01-01

    Autism Spectrum Disorders (ASD) are behaviorally defined neurodevelopmental disorders. The best known yet less understood characteristic of autism is its unexplained male preponderance. Using a biosocial perspective, the goal of this article is to draw attention to the role of gender-based socialization practices and behavioral expectations during

  16. Opinion: Sex, Gender and the Diagnosis of Autism--A Biosocial View of the Male Preponderance

    ERIC Educational Resources Information Center

    Goldman, Sylvie

    2013-01-01

    Autism Spectrum Disorders (ASD) are behaviorally defined neurodevelopmental disorders. The best known yet less understood characteristic of autism is its unexplained male preponderance. Using a biosocial perspective, the goal of this article is to draw attention to the role of gender-based socialization practices and behavioral expectations during…

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

    PubMed

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

    2013-09-17

    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. 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

  19. 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.

  20. A Tandem Duplicate of Anti-Mllerian Hormone with a Missense SNP on the Y Chromosome Is Essential for Male Sex Determination in Nile Tilapia, Oreochromis niloticus.

    PubMed

    Li, Minghui; Sun, Yunlv; Zhao, Jiue; Shi, Hongjuan; Zeng, Sheng; Ye, Kai; Jiang, Dongneng; Zhou, Linyan; Sun, Lina; Tao, Wenjing; Nagahama, Yoshitaka; Kocher, Thomas D; Wang, Deshou

    2015-11-01

    Variation in the TGF-? signaling pathway is emerging as an important mechanism by which gonadal sex determination is controlled in teleosts. Here we show that amhy, a Y-specific duplicate of the anti-Mllerian hormone (amh) gene, induces male sex determination in Nile tilapia. amhy is a tandem duplicate located immediately downstream of amh?-y on the Y chromosome. The coding sequence of amhy was identical to the X-linked amh (amh) except a missense SNP (C/T) which changes an amino acid (Ser/Leu92) in the N-terminal region. amhy lacks 5608 bp of promoter sequence that is found in the X-linked amh homolog. The amh?-y contains several insertions and deletions in the promoter region, and even a 5 bp insertion in exonVI that results in a premature stop codon and thus a truncated protein product lacking the TGF-? binding domain. Both amhy and amh?-y expression is restricted to XY gonads from 5 days after hatching (dah) onwards. CRISPR/Cas9 knockout of amhy in XY fish resulted in male to female sex reversal, while mutation of amh?-y alone could not. In contrast, overexpression of Amhy in XX fish, using a fosmid transgene that carries the amhy/amh?-y haplotype or a vector containing amhy ORF under the control of CMV promoter, resulted in female to male sex reversal, while overexpression of Amh?-y alone in XX fish could not. Knockout of the anti-Mllerian hormone receptor type II (amhrII) in XY fish also resulted in 100% complete male to female sex reversal. Taken together, these results strongly suggest that the duplicated amhy with a missense SNP is the candidate sex determining gene and amhy/amhrII signal is essential for male sex determination in Nile tilapia. These findings highlight the conserved roles of TGF-? signaling pathway in fish sex determination. PMID:26588702

  1. Conditioned same-sex partner preference in male rats is facilitated by oxytocin and dopamine: effect on sexually dimorphic brain nuclei.

    PubMed

    Triana-Del Rio, Rodrigo; Tecamachaltzi-Silvarn, Miriam B; Daz-Estrada, Victor X; Herrera-Covarrubias, Deissy; Corona-Morales, Aleph A; Pfaus, James G; Coria-Avila, Genaro A

    2015-04-15

    Conditioned same-sex partner preference can develop in male rats that undergo cohabitation under the effects of quinpirole (QNP, D2 agonist). Herein, we assessed the development of conditioned same-sex social/sexual preference in males that received either nothing, saline, QNP, oxytocin (OT), or QNP+OT during cohabitation with another male (+) or single-caged (-). This resulted in the following groups: (1) Intact-, (2) Saline+, (3) QNP-, (4) OT-, (5) QNP+, (6) OT+ and (7) QNP/OT+. Cohabitation occurred during 24h in a clean cage with a male partner that bore almond scent on the back as conditioned stimulus. This was repeated every 4 days for a total of three trials. Social and sexual preference were assessed four days after the last conditioning trial in a drug-free test in which experimental males chose between the scented familiar male and a novel sexually receptive female. Results showed that males from groups Intact-, Saline+, QNP- and OT- displayed a clear preference for the female (opposite-sex), whereas groups QNP+, OT+ and QNP/OT+ displayed socio/sexual preference for the male partner (same-sex). In Experiment 2, the brains were processed for Nissl dye and the area size of two sexually dimorphic nuclei (SDN-POA and SON) was compared between groups. Males from groups OT-, OT+ and QNP/OT+ expressed a smaller SDN-POA and groups QNP+ and QNP/OT+ expressed a larger SON. Accordingly, conditioned same-sex social/sexual partner preference can develop during cohabitation under enhanced D2 or OT activity but such preference does not depend on the area size of those sexually dimorphic nuclei. PMID:25601575

  2. 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

  3. Developmental alterations of the C. elegans male anal depressor morphology and function require sex-specific cell autonomous and cell non-autonomous interactions.

    PubMed

    Chen, Xin; Ren Garca, L

    2015-02-01

    We studied the Caenorhabditis elegans anal depressor development in larval males and hermaphrodites to address how a differentiated cell sex-specifically changes its morphology prior to adulthood. In both sexes, the larval anal depressor muscle is used for defecation behavior. However in the adult males, the muscle's sarcomere is reorganized to facilitate copulation. To address when the changes occur in the anal depressor, we used YFP:actin to monitor, and mutant analysis, laser-ablation and transgenic feminization to perturb the cell's morphological dynamics. In L1 and L2 stage larva, the muscle of both sexes has similar sarcomere morphology, but the hermaphrodite sex-determination system promotes more growth. The male anal depressor begins to change in the L3 stage, first by retracting its muscle arm from the neurons of the defecation circuit. Then the muscle's ventral region develops a slit that demarcates an anterior and posterior domain. This demarcation is not dependent on the anal depressor's intrinsic genetic sex, but is influenced by extrinsic interactions with the developing male sex muscles. However, subsequent changes are dependent on the cell's sex. In the L4 stage, the anterior domain first disassembles the dorsal-ventral sarcomere region and develops filopodia that elongates anteriorly towards the spicule muscles. Later, the posterior domain dissembles the remnants of its sarcomere, but still retains a vestigial attachment to the ventral body wall. Finally, the anterior domain attaches to the sex muscles, and then reassembles an anterior-posteriorly oriented sarcomere. Our work identifies key steps in the dimorphic re-sculpting of the anal depressor that are regulated by genetic sex and by cell-cell signaling. PMID:25498482

  4. 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

  5. Factors Influencing Male Plutella xylostella (Lepidoptera: Plutellidae) Capture Rates in Sex Pheromone-Baited Traps on Canola in Western Canada.

    PubMed

    Miluch, C E; Dosdall, L M; Evenden, M L

    2014-12-01

    Optimization of male moth trapping rates in sex pheromone-baited traps plays a key role in managing Plutella xylostella (L.). We investigated various ways to increase the attractiveness of pheromone-baited traps to P. xylostella in canola agroecosystems in AB, Canada. Factors tested included pheromone blend and dose, addition of a green leaf volatile to the pheromone at different times during the season, lure type, trap color, and height. The industry standard dose of 100 ?g of pheromone (four-component blend) per lure (ConTech Enterprises Inc., Delta, British Columbia [BC], Canada) captured the most moths in the two lure types tested. Traps baited with pheromone released from gray rubber septa captured more males than those baited with red rubber septa. Traps baited with lures in which Z11-16: Ac is the main component attracted significantly more moths than those in which Z11-16: Ald is the main component. The addition of the green leaf volatile, (Z)-3-hexenyl acetate, to pheromone at a range of doses, did not increase moth capture at any point during the canola growing season. Unpainted white traps captured significantly more male moths than pheromone-baited traps that were painted yellow. Trap height had no significant effect on moth capture. Recommendations for monitoring P. xylostella in canola agroecosystems of western Canada include using a pheromone blend with Z11-16: Ac as the main component released from gray rubber septa at a dose of 100 ?g. PMID:26470071

  6. Battle of the sex steroids in the male skeleton: and the winner is.

    PubMed

    Weber, Thomas J

    2016-03-01

    Male osteoporosis is a multifactorial disease, although it is often in part related to hypogonadism. While testosterone replacement therapy has been shown to improve bone mineral density, studies have also linked bone loss and higher fracture risk in men to low estrogen levels. In this issue of the JCI, Finkelstein and colleagues report the results of a clinical study in a cohort of healthy adult men aimed at further discerning the specific roles of androgen and estrogen deficiency in bone loss. The results of their study support previous findings that estrogen deficiency has a dramatic effect on bone homeostasis in men. Future studies to corroborate and expand on these findings have potential to influence the clinical management of male osteoporosis. PMID:26901810

  7. 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

  8. 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 g and higher. The activity was dose-dependent, being optimum at 1 g 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

  9. Male reproductive organs are at risk from environmental hazards.

    PubMed

    Bonde, Jens Peter

    2010-03-01

    Male reproductive disorders that are of interest from an environmental point of view include sexual dysfunction, infertility, cryptorchidism, hypospadias and testicular cancer. Several reports suggest declining sperm counts and increase of these reproductive disorders in some areas during some time periods past 50 years. Except for testicular cancer this evidence is circumstantial and needs cautious interpretation. However, the male germ line is one of the most sensitive tissues to the damaging effects of ionizing radiation, radiant heat and a number of known toxicants. So far occupational hazards are the best documented risk factors for impaired male reproductive function and include physical exposures (radiant heat, ionizing radiation, high frequency electromagnetic radiation), chemical exposures (some solvents as carbon disulfide and ethylene glycol ethers, some pesticides as dibromochloropropane, ethylendibromide and DDT/DDE, some heavy metals as inorganic lead and mercury) and work processes such as metal welding. Improved working conditions in affluent countries have dramatically decreased known hazardous workplace exposures, but millions of workers in less affluent countries are at risk from reproductive toxicants. New data show that environmental low-level exposure to biopersistent pollutants in the diet may pose a risk to people in all parts of the world. For other toxicants the evidence is only suggestive and further evaluation is needed before conclusions can be drawn. Whether compounds as phthalates, bisphenol A and boron that are present in a large number of industrial and consumer products entails a risk remains to be established. The same applies to psychosocial stressors and use of mobile phones. Finally, there are data indicating a particular vulnerability of the fetal testis to toxicants-for instance maternal tobacco smoking. Time has come where male reproductive toxicity should be addressed form entirely new angles including exposures very early in life. PMID:19966832

  10. Female sex pheromone and male behavioral responses of the bombycid moth Trilocha varians: comparison with those of the domesticated silkmoth Bombyx mori

    NASA Astrophysics Data System (ADS)

    Daimon, Takaaki; Fujii, Takeshi; Yago, Masaya; Hsu, Yu-Feng; Nakajima, Yumiko; Fujii, Tsuguru; Katsuma, Susumu; Ishikawa, Yukio; Shimada, Toru

    2012-03-01

    Analysis of female sex pheromone components and subsequent field trap experiments demonstrated that the bombycid moth Trilocha varians uses a mixture of ( E, Z)-10,12-hexadecadienal (bombykal) and ( E,Z)-10,12-hexadecadienyl acetate (bombykyl acetate) as a sex pheromone. Both of these components are derivatives of ( E,Z)-10,12-hexadecadienol (bombykol), the sex pheromone of the domesticated silkmoth Bombyx mori. This finding prompted us to compare the antennal and behavioral responses of T. varians and B. mori to bombykol, bombykal, and bombykyl acetate in detail. The antennae of T. varians males responded to bombykal and bombykyl acetate but not to bombykol, and males were attracted only when lures contained both bombykal and bombykyl acetate. In contrast, the antennae of B. mori males responded to all the three components. Behavioral analysis showed that B. mori males responded to neither bombykal nor bombykyl acetate. Meanwhile, the wing fluttering response of B. mori males to bombykol was strongly inhibited by bombykal and bombykyl acetate, thereby indicating that bombykal and bombykyl acetate act as behavioral antagonists for B. mori males. T. varians would serve as a reference species for B. mori in future investigations into the molecular mechanisms underlying the evolution of sex pheromone communication systems in bombycid moths.

  11. Epigenetics and sex differences in the brain: A genome-wide comparison of histone-3 lysine-4 trimethylation (H3K4me3) in male and female mice.

    PubMed

    Shen, Erica Y; Ahern, Todd H; Cheung, Iris; Straubhaar, Juerg; Dincer, Aslihan; Houston, Isaac; de Vries, Geert J; Akbarian, Schahram; Forger, Nancy G

    2015-06-01

    Many neurological and psychiatric disorders exhibit gender disparities, and sex differences in the brain likely explain some of these effects. Recent work in rodents points to a role for epigenetics in the development or maintenance of neural sex differences, although genome-wide studies have so far been lacking. Here we review the existing literature on epigenetics and brain sexual differentiation and present preliminary analyses on the genome-wide distribution of histone-3 lysine-4 trimethylation in a sexually dimorphic brain region in male and female mice. H3K4me3 is a histone mark primarily organized as 'peaks' surrounding the transcription start site of active genes. We microdissected the bed nucleus of the stria terminalis and preoptic area (BNST/POA) in adult male and female mice and used ChIP-Seq to compare the distribution of H3K4me3 throughout the genome. We found 248 genes and loci with a significant sex difference in H3K4me3. Of these, the majority (71%) had larger H3K4me3 peaks in females. Comparisons with existing databases indicate that genes and loci with increased H3K4me3 in females are associated with synaptic function and with expression atlases from related brain areas. Based on RT-PCR, only a minority of genes with a sex difference in H3K4me3 has detectable sex differences in expression at baseline conditions. Together with previous findings, our data suggest that there may be sex biases in the use of epigenetic marks. Such biases could underlie sex differences in vulnerabilities to drugs or diseases that disrupt specific epigenetic processes. PMID:25131640

  12. Minority stress in same-sex male relationships: when does it impact relationship satisfaction?

    PubMed

    Kamen, Charles; Burns, Michelle; Beach, Steven R H

    2011-01-01

    The minority stress model (Meyer, 2003) has been proposed to explain higher rates of psychopathology in lesbian, gay, and bisexual individuals. However, studies of minority stress have rarely taken into account the interface between minority stress and same-sex relationship processes. In the current study, 142 gay men in romantic relationships completed an online survey assessing minority stress constructs, relationship features, and relationship satisfaction. Minority stress was not directly related to relationship satisfaction, while commitment, trust, and support from one's partner were related to relationship satisfaction. Significant moderation effects emerged between discrimination and trust and between internalized heterosexism and commitment, indicating that trust was related to satisfaction for those who had experienced frequent discrimination, while commitment was related to satisfaction for those low in internalized heterosexism. PMID:22029562

  13. 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

  14. 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.

  15. 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

  16. Toxic responses to deltamethrin (DM) low doses on gonads, sex hormones and lipoperoxidation in male rats following subcutaneous treatments.

    PubMed

    Issam, Chargui; Samir, Haouem; Zohra, Haouas; Monia, Zaouali; Hassen, Ben Cheikh

    2009-12-01

    Deltamethrin (DM) is a alpha- cyano pyrethroid insecticide used extensively in pest control. Although initially thought to be least toxic, a number of recent reports showed its toxicity in mammalian and non-mammalian laboratory and wildlife animal species. The present study, carried out in male rats, is a contribution to explore some mechanisms underlying DM toxicity. The aim of the present research was to investigate the effect of different subcutaneous treatments with DM (2 ppm for 30 days, 20 ppm for 45 days and 200 ppm for 60 days) on testes histopathology, sex hormones and oxidative stress from male rats. Our study mentioned an hypospermatogenesis within the testes accompanied by some apoptotic figures in particular cell fragments into the seminiferous tubules (ST)' lumen. The results obtained show that follicule-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone can be differently influenced in rats. In fact, findings of the present investigation mention a significant decrease (p < or = 0.05) of FSH, LH and testosterone at the highest DM dose. Whereas a significant reduction of FSH was noticed after 45 days of treatment. The assessment of oxidative stress by malondialdehyde (MDA) measurements in plasma revealed a significant increase of this parameter after 30 days, 45 days or 60 days. In conclusion the study shows that subcutaneous DM treatment produces an arrest of spermatogenesis, a significant disharmony in sex hormones and MDA levels in rats that is related to dose, length of treatment and to the lipid peroxidation which may be one of the molecular mechanisms involved in DM-induced gonads toxicity. PMID:19952501

  17. Can Male Circumcision Have an Impact on the HIV Epidemic in Men Who Have Sex with Men?

    PubMed Central

    Goodreau, Steven M.; Carnegie, Nicole B.; Vittinghoff, Eric; Lama, Javier R.; Fuchs, Jonathan D.; Sanchez, Jorge; Buchbinder, Susan P.

    2014-01-01

    Background Three trials have demonstrated the prophylactic effect of male circumcision (MC) for HIV acquisition among heterosexuals, and MC interventions are underway throughout sub-Saharan Africa. Similar efforts for men who have sex with men (MSM) are stymied by the potential for circumcised MSM to acquire HIV easily through receptive sex and transmit easily through insertive sex. Existing work suggests that MC for MSM should reach its maximum potential in settings where sexual role segregation is historically high and relatively stable across the lifecourse; HIV incidence among MSM is high; reported willingness for prophylactic circumcision is high; and pre-existing circumcision rates are low. We aim to identify the likely public health impact that MC interventions among MSM would have in one setting that fulfills these conditions—Peru—as a theoretical upper bound for their effectiveness among MSM generally. Methods and Findings We use a dynamic, stochastic sexual network model based in exponential-family random graph modeling and parameterized from multiple behavioral surveys of Peruvian MSM. We consider three enrollment criteria (insertive during 100%, >80% or >60% of UAI) and two levels of uptake (25% and 50% of eligible men); we explore sexual role proportions from two studies and different frequencies of switching among role categories. Each scenario is simulated 10 times. We estimate that efficiency could reach one case averted per 6 circumcisions. However, the population-level impact of an optimistic MSM-MC intervention in this setting would likely be at most ∼5–10% incidence and prevalence reductions over 25 years. Conclusions Roll-out of MC for MSM in Peru would not result in a substantial reduction in new HIV infections, despite characteristics in this population that could maximize such effects. Additional studies are needed to confirm these results for other MSM populations, and providers may consider the individual health benefits of offering MC to their MSM patients. PMID:25076493

  18. 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

    2014-07-01

    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

  19. Annual changes in serum sex steroids in male and female black (Ursus americanus) and polar (Ursus maritimus) bears.

    PubMed

    Palmer, S S; Nelson, R A; Ramsay, M A; Stirling, I; Bahr, J M

    1988-06-01

    The adaptation of black and polar bears to their environments is proportional to the severity of climate and food restriction. Both black and polar bears mate during the spring, despite differences in their recent metabolic state. Reproductive activity in black bears follows 4 mo of torpor, whereas reproduction in polar bears occurs prior to torpor. The goals of this study were to measure the annual changes in serum sex steroids in male and female black and polar bears, and to determine if changes in serum levels of these steroids were associated with metabolic condition or photoperiod. Serum testosterone (T) concentrations were elevated during spring in black and polar bears. Moreover, this increase in serum T in polar bears during spring was correlated with age and testis size. Serum progesterone (P4) concentrations increased in pregnant polar bears in fall coincident with the time of expected implantation. No increases in serum P4 were observed in nonpregnant black and polar bears. Serum estradiol (E2) was elevated in nonpregnant and pregnant polar bears 2 mo prior to the time of expected implantation. We found that serum sex steroids measured in black and polar bears change independent of torpor. Therefore, our results suggest that photoperiod may be a more important regulator of serum steroid levels and reproduction than metabolic condition. PMID:3408772

  20. Female Sex Workers, Male Circumcision and HIV: A Qualitative Study of Their Understanding, Experience, and HIV Risk in Zambia

    PubMed Central

    Abbott, Sharon A.; Haberland, Nicole A.; Mulenga, Drosin M.; Hewett, Paul C.

    2013-01-01

    Several sub-Saharan African countries, including Zambia, have initiated national voluntary medical male circumcision (MC) programs to reduce HIV incidence. In-depth interviews were conducted with twenty female sex workers (FSWs) in Lusaka to examine their understanding of MC and experiences with circumcised clients. Knowledge of MC was derived primarily through informal sources, with very few FSWs reporting exposure to MC educational campaigns. MC was not widely believed to be protective against HIV, however it was viewed by some as protective against STIs. Three FSWs reported having sex with recently circumcised clients, and most reported that men often used their MC status to try to convince FSWs to forego condoms. Findings suggest that FSWs, already at high risk for HIV infection, may face additional pressure toward higher risk behavior as a result of MC. As MC services are expanded, programs should support FSWs' efforts to protect themselves by providing information about what MC can - and cannot - offer for HIV/STI infection prevention. PMID:23349745

  1. Testicular disorder of sex development in four cats with a male karyotype (38,XY; SRY-positive).

    PubMed

    Nowacka-Woszuk, Joanna; Szczerbal, Izabela; Salamon, Sylwia; Kociucka, Beata; Jackowiak, Hanna; Prozorowska, Ewelina; Slaska, Brygida; Rozanska, Dorota; Orzelski, Maciej; Ochota, Malgorzata; Dzimira, Stanislaw; Lipiec, Magdalena; Nizanski, Wojciech; Switonski, Marek

    2014-12-10

    The molecular background of disorders of sex development (DSD) in cats is poorly recognized. In this study we present cytogenetic, molecular and histological analyses of four cats subjected for the analysis due to ambiguous external genitalia. Three cases, with rudimentary penises and an abnormal position of the urethral orifice, represented different types of hypospadias. The fourth case had a normal penis, a blind vulva and spermatogenetically active testes. Histological studies showed structures typical of testes, but spermatogenic activity was observed in two cats only. All the cats had a normal male chromosome complement (38,XY) and the Y-chromosome linked genes (SRY and ZFY) were also detected. Fluorescent in situ hybridization (FISH), with the use of the feline BAC probe harboring the SRY gene, excluded the possibility of chromosome translocation of the Y chromosome fragment carrying the SRY gene onto another chromosome. Sequencing of four candidate genes (SRY--sex determining region Y; AR--androgen receptor; SRD5A2--steroid-5-alfa reductase 2 and MAMLD1--mastermind-like domain containing (1) revealed one SNP in the SRY gene, one common polymorphism in exon 1 of the AR gene (tandem repeat of a tri-nucleotide motif--CAG), six polymorphisms (5 SNPs and 1 indel) in the SRD5A2 gene and one SNP in the MAMLD1 gene. Molecular studies of the candidate genes showed no association with the identified polymorphisms, thus molecular background of the studied DSD phenotypes remains unknown. PMID:25455261

  2. 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

  3. "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

  4. Genetic Control of Male Germ Unit Organization in Arabidopsis1

    PubMed Central

    Lalanne, Eric; Twell, David

    2002-01-01

    In flowering plants, the vegetative nucleus and the two sperm cells are proposed to form a functional assemblage, the male germ unit (MGU). Here, we describe the developmental pathway of MGU assembly in Arabidopsis and report two classes of mutations that affect the integrity and/or the positioning of the MGU in the mature pollen grain. In germ unit malformed (gum) mutants, the vegetative nucleus is positioned adjacent to the pollen grain wall, separate from the two sperm cells, whereas in MGU displaced (mud) mutants, the intact MGU is displaced to the pollen grain wall. mud and gum mutants correspond to male-specific gametophytic mutations that also reduce pollen fitness. Genetic mapping showed that the gum1 and gum2 mutations are genetically linked, possibly allelic, whereas the mud1 and mud2 mutations correspond to two unlinked loci mapping on different chromosomes. The hierarchical relationship between mud and gum mutations was investigated by phenotypic analysis of double mutants. gum1 appeared to act earlier than mud1 and mud2, affecting initial MGU assembly and its stability during pollen maturation. In contrast, mud1 and mud2 mutations appear to act only on MGU positioning during final maturation. From in planta analyses of pollen germination in mud and gum mutants, we conclude that the initial proximity and positioning of MGU components is not required for their entrance into the pollen tube, but the efficiency of MGU translocation is reduced. PMID:12068125

  5. A formal theory for male-preferring stopping rules of childbearing: sex differences in birth order and in the number of siblings.

    PubMed

    Yamaguchi, K

    1989-08-01

    Through mathematical deductions, this article shows certain macro-demographic consequences of individually employed male-preferring stopping rules in childbearing. It is shown that male-preferring stopping rules generate differences between boys and girls in birth order and in the number of siblings. Two situations are considered regarding the latent probability of having a boy: population homogeneity and population heterogeneity. The sex difference in the number of siblings exists even under population homogeneity, and the difference remains constant when each couple employs a distinct alternative rule. On the other hand, the sex difference in the birth order exists only under population heterogeneity. Substantive implications of these findings are discussed. PMID:2792480

  6. (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

  7. Evidence of female sex pheromones and characterization of the cuticular lipids of unfed, adult male versus female blacklegged ticks, Ixodes scapularis.

    PubMed

    Carr, Ann L; Sonenshine, Daniel E; Strider, John B; Roe, R Michael

    2016-04-01

    Copulation in Ixodes scapularis involves physical contact between the male and female (on or off the host), male mounting of the female, insertion/maintenance of the male chelicerae in the female genital pore (initiates spermatophore production), and the transfer of the spermatophore by the male into the female genital pore. Bioassays determined that male mounting behavior/chelicerae insertion required direct contact with the female likely requiring non-volatile chemical cues with no evidence of a female volatile sex pheromone to attract males. Unfed virgin adult females and replete mated adult females elicited the highest rates of male chelicerae insertion with part fed virgin adult females exhibiting a much lower response. Whole body surface hexane extracts of unfed virgin adult females and males, separately analyzed by GC-MS, identified a number of novel tick surface associated compounds: fatty alcohols (1-hexadecanol and 1-heptanol), a fatty amide (erucylamid), aromatic hydrocarbons, a short chain alkene (1-heptene), and a carboxylic acid ester (5β-androstane). These compounds are discussed in terms of their potential role in female-male communication. The two most abundant fatty acid esters found were butyl palmitate and butyl stearate present in ratios that were sex specific. Only 6 n-saturated hydrocarbons were identified in I. scapularis ranging from 10 to 18 carbons. PMID:26864785

  8. The effects of mesterolone, a male sex hormone in depressed patients (a double blind controlled study).

    PubMed

    Itil, T M; Michael, S T; Shapiro, D M; Itil, K Z

    1984-06-01

    Based on computer EEG (CEEG) profiles, in high doses, antidepressant properties of mesterolone, a synthetic androgen, were predicted. In a double-blind placebo controlled study, the clinical effects of 300-450 mg daily mesterolone were investigated in 52 relatively young (age range 26-53 years, mean 42.7 years) male depressed outpatients. During 6 weeks of mesterolone treatment, there was a significant improvement of depressive symptomatology. However, since an improvement was also established during the placebo treatment, no statistically appreciable difference in the therapeutic effects of mesterolone was established compared to placebo. Mesterolone treatment significantly decreased both plasma testosterone and protein bound testosterone levels. Patients with high testosterone levels prior to treatment seem to have had more benefit from mesterolone treatment than patients with low testosterone levels. The degree of improvement weakly correlated to the decrease of testosterone levels during mesterolone treatment. PMID:6431212

  9. Sex Pheromones of C. elegans Males Prime the Female Reproductive System and Ameliorate the Effects of Heat Stress.

    PubMed

    Aprison, Erin Z; Ruvinsky, Ilya

    2015-12-01

    Pheromones are secreted molecules that mediate animal communications. These olfactory signals can have substantial effects on physiology and likely play important roles in organismal survival in natural habitats. Here we show that a blend of two ascaroside pheromones produced by C. elegans males primes the female reproductive system in part by improving sperm guidance toward oocytes. Worms have different physiological responses to different ratios of the same two molecules, revealing an efficient mechanism for increasing coding potential of a limited repertoire of molecular signals. The endogenous function of the male sex pheromones has an important side benefit. It substantially ameliorates the detrimental effects of prolonged heat stress on hermaphrodite reproduction because it increases the effectiveness with which surviving gametes are used following stress. Hermaphroditic species are expected to lose female-specific traits in the course of evolution. Our results suggest that some of these traits could have serendipitous utility due to their ability to counter the effects of stress. We propose that this is a general mechanism by which some mating-related functions could be retained in hermaphroditic species, despite their expected decay. PMID:26645097

  10. Sex Pheromones of C. elegans Males Prime the Female Reproductive System and Ameliorate the Effects of Heat Stress

    PubMed Central

    Aprison, Erin Z.; Ruvinsky, Ilya

    2015-01-01

    Pheromones are secreted molecules that mediate animal communications. These olfactory signals can have substantial effects on physiology and likely play important roles in organismal survival in natural habitats. Here we show that a blend of two ascaroside pheromones produced by C. elegans males primes the female reproductive system in part by improving sperm guidance toward oocytes. Worms have different physiological responses to different ratios of the same two molecules, revealing an efficient mechanism for increasing coding potential of a limited repertoire of molecular signals. The endogenous function of the male sex pheromones has an important side benefit. It substantially ameliorates the detrimental effects of prolonged heat stress on hermaphrodite reproduction because it increases the effectiveness with which surviving gametes are used following stress. Hermaphroditic species are expected to lose female-specific traits in the course of evolution. Our results suggest that some of these traits could have serendipitous utility due to their ability to counter the effects of stress. We propose that this is a general mechanism by which some mating-related functions could be retained in hermaphroditic species, despite their expected decay. PMID:26645097

  11. Prenatal letrozole produces a subpopulation of male rats with same-sex preference and arousal as well as female sexual behavior.

    PubMed

    Olvera-Hernndez, Sandra; Chavira, Roberto; Fernndez-Guasti, Alonso

    2015-02-01

    Disruption of the sexual differentiation process during critical periods in male rodents produces changes in partner preference and sexual behavior. In this study we used prenatal (gestation days 10-22) letrozole (0.31 and 0.56 ?g/kg) to inhibit aromatase and alter normal sexual differentiation of males. These animals and control rats (injected with vehicle) were used when adults to study: a) sexual preference (where the experimental male could choose to interact with a receptive female or a sexually experienced male); b) masculine and feminine sexual behaviors (tested in cylindrical arenas); c) non-contact erections when exposed to a female or a male and, d) serum sex steroids and gonadotropin levels. The results showed that 30% of the males treated with letrozole (0.56 ?g/kg) had same-sex preference, 33% displayed lordosis and 63% showed non-contact erections in the presence of a sexually experienced male. However, 44% of these males also exhibited complete masculine sexual behavior towards receptive females. None of the control males displayed lordosis when mounted by another male and very few (12%) showed non-contact erections when exposed to a sexually experienced male. Similar low percentages were found in those males prenatally treated with the low letrozole dose (0.31 ?g/kg). No difference was found in the serum levels of testosterone, estradiol, LH and FSH between control and letrozole-treated males regardless of their sexual preference. These results indicate that prenatal selective inhibition of aromatization produces feminization of sexual partner preference, arousal and sexual behavior but does not affect masculine sexual behavior. PMID:25462593

  12. First Record of the Scarab Beetle, Phyllophaga lissopyge from South America, with Descriptions of Adult Seasonal Activity and Male Response to Sex Attractants

    PubMed Central

    Morales-Rodriguez, Anuar; Peck, Daniel C.; Robbins, Paul S.

    2011-01-01

    Phyllophaga lissopyge (Bates) (Coleoptera: Scarabaeidae: Melolonthinae) is reported for the first time from South America. Male sex pheromone response is described for P. lissopyge and two other co-occurring Phyllophaga species. Adults of P. lissopyge and P. menetriesi (Blanchard) flew to traps baited with methyl 2-(methylthio) benzoate whereas adults of P. obsoleta (Blanchard) flew irregularly to four different pheromone compounds. Adult seasonal activity is described from males captures in Rionegro, Antioquia, Colombia. PMID:21529153

  13. 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.

  14. 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

  15. The reported sex and surgery satisfactions of 28 postoperative male-to-female transsexual patients.

    PubMed

    Rehman, J; Lazer, S; Benet, A E; Schaefer, L C; Melman, A

    1999-02-01

    From 1980 to July 1997 sixty-one male-to-female gender transformation surgeries were performed at our university center by one author (A.M.). Data were collected from patients who had surgery up to 1994 (n = 47) to obtain a minimum follow-up of 3 years; 28 patients were contacted. A mail questionnaire was supplemented by personal interviews with 11 patients and telephone interviews with remaining patients to obtain and clarify additional information. Physical and functional results of surgery were judged to be good, with few patients requiring additional corrective surgery. General satisfaction was expressed over the quality of cosmetic (normal appearing genitalia) and functional (ability to perceive orgasm) results. Follow-up showed satisfied who believed they had normal appearing genitalia and the ability to experience orgasm. Most patients were able to return to their jobs and live a more satisfactory social and personal life. One significant outcome was the importance of proper preparation of patients for surgery and especially the need for additional postoperative psychotherapy. None of the patients regretted having had surgery. However, some were, to a degree, disappointed because of difficulties experienced postoperatively in adjusting satisfactorily as women both in their relationships with men and in living their lives generally as women. Findings of this study make a strong case for making a change in the Harry Benjamin Standards of Care to include a period of postoperative psychotherapy. PMID:10097806

  16. The Structure, Stability and Pheromone Binding of the Male Mouse Protein Sex Pheromone Darcin

    PubMed Central

    Phelan, Marie M.; McLean, Lynn; Armstrong, Stuart D.; Hurst, Jane L.; Beynon, Robert J.; Lian, Lu-Yun

    2014-01-01

    Mouse urine contains highly polymorphic major urinary proteins that have multiple functions in scent communication through their abilities to bind, transport and release hydrophobic volatile pheromones. The mouse genome encodes for about 20 of these proteins and are classified, based on amino acid sequence similarity and tissue expression patterns, as either central or peripheral major urinary proteins. Darcin is a male specific peripheral major urinary protein and is distinctive in its role in inherent female attraction. A comparison of the structure and biophysical properties of darcin with MUP11, which belongs to the central class, highlights similarity in the overall structure between the two proteins. The thermodynamic stability, however, differs between the two proteins, with darcin being much more stable. Furthermore, the affinity of a small pheromone mimetic is higher for darcin, although darcin is more discriminatory, being unable to bind bulkier ligands. These attributes are due to the hydrophobic ligand binding cavity of darcin being smaller, caused by the presence of larger amino acid side chains. Thus, the physical and chemical characteristics of the binding cavity, together with its extreme stability, are consistent with darcin being able to exert its function after release into the environment. PMID:25279835

  17. Cypermetherin toxic effects on spermatogenesis and male mouse reproductive organs.

    PubMed

    Dahamna, S; Bencheikh, F; Harzallah, D; Boussahel, S; Belgeit, A; Merghem, M; Bouriche, H

    2010-01-01

    Cypermetherin has been implicated in the development of a variety of reproductive disorders in humans and infertility in wild life, where it increases the death rate of the offspring and induces aggressiveness (Elbetieha et al., 2001). Studies in workers exposed to handling of agro pesticides indicate that they have defects in their reproduction capabilities characterized by infertility and/or a decrease in the fertilizing potential, fetal death. In this study, mice weighing 30-35 g were used, separated in 3 groups, (1) control (2) vehicle (oil) and (3) experimental (Cypermetherin and oil). The animals were gavaged by 1/5, 1/20 LD50 for 2 and 4 weeks respectively, and with 1/5 LD50 for 12 weeks, then sacrificed. Epididymal spermatozoa were evaluated with respect to quantity, motility and morphology. The histology of testis and epididymis was also studied. Sperm count decreased by around 20% in treated animals compared with control. Teratology observations showed a clear modification of sperm morphology, especially the flagella. Testicular and epididymal morphology was also impaired. It is concluded that Cypermetherin may cause morphological and functional alteration of the male reproductive tract. PMID:21542485

  18. Early postnatal estrogen organizes sex differences in the extinction of a CRF running response.

    PubMed

    Sánchez-Santed, F; Calés, J M; Enriquez, P; Guillamón, A

    1993-01-01

    In the present study the organizational effects of sex steroids on the sexually dimorphic extinction of a continuously food-rewarded running response were investigated. Gonadally intact female rats neonatally treated from day 1 to day 8 of the postnatal life with estradiol benzoate (EB), dihydrotestosterone (DHT) or vehicle, and males treated in the same period with the antiandrogen ciproterone acetate (AC), the estrogen antagonist tamoxifen (TX) or vehicle were studied in adulthood during the acquisition and extinction phases of the response in a short and narrow runway. No difference in performance between groups was obtained in the response acquisition. However, during extinction control males extinguished faster than control females. DHT treatment to females and neonatal CA administration to males had no effect on the expression of sexual dimorphism. Conversely, TX administration to the males increased male's resistance to extinction at the levels shown by control or DHT females, whereas the females treated with EB exhibited similar extinction rates to those observed in nonhormonal treated or CA males. This finding suggests that the organizational effect of testosterone on the sexually dimorphic behavior studied in the present report are mediated by testosterone conversion to estradiol throughout the aromatization pathway in the brain. PMID:8457912

  19. 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

  20. Trends in Infectious Diseases and the Male to Female Ratio: Possible Clues to Changes in Behavior among Men Who Have Sex with Men

    ERIC Educational Resources Information Center

    Beltrami, John F.; Shouse, R. Luke; Blake, Paul A.

    2005-01-01

    Men who have sex with men (MSM) are a priority population for HIV care and prevention programs. This report describes HIV and other sexually transmitted disease (STD) trends among MSM in metropolitan Atlanta by analyzing nine databases. We describe the use of the male-to-female (M:F) ratio, a surrogate marker for MSM in databases without

  1. Hetero- and isosexual pseudoprecocity associated with testicular sex-cord tumors in an 8 year-old male.

    PubMed

    Diamond, F B; Root, A W; Hoover, D L; Monteforte, H

    1996-01-01

    Enlargement of the right breast, axillary hair, and acceleration of linear growth rate were first noted at 8 years of age in an otherwise healthy male with no known exposure to exogenous hormones. At 9.5 years of age the right subareolar mass was excised; histologic examination revealed fibrous breast tissue. Subsequently pubic hair appeared. At 10.7 years of age, the patient complained of right inguinal pain after a minor injury. Examination revealed a tall (height age 12.7 years), mature, muscular boy with enlarged (R: 5 x 3 x 2 cm; L: 3 x 2 x 3 cm) firm, irregular testes, Tanner stage II pubic hair, and modest axillary hair. No perioral pigmentation was present. Testicular ultrasonography revealed multilobular echogenic foci with calcifications. Bone age was 13 years, the LH and FSH secretory responses to GnRH were minimal (LH: < 0.038-->0.28 mIU/ml; FSH: < 0.063-->0.11 mIU/ml), and basal serum testosterone (< 10 ng/dl) and estradiol (< 10 pg/ml) values were undetectable. Following administration of human chorionic gonadotropin (hCG), the serum testosterone concentration increased to 275 ng/dl, while estradiol remained unmeasurable. Spermatic vein concentrations of testosterone were undetectable in the basal state and increased after hCG administration. After bilateral orchiectomy, pathologic examination revealed multifocal tumors composed of brightly eosinophilic, large polygonal cells arranged in nests, cords, and clusters within dense connective tissue or mucinous stroma with lamellar calcifications of varying sizes. These pathologic findings were compatible with a large cell calcifying Sertoli cell (sex-cord)tumor of the testes. Testosterone, estradiol, immunoreactive and bioactive aromatase activity were not detectable in the tumor. Thus, both heterosexual (gynecomastia) and isosexual (increased musculature, pubic and axillary hair) precocious puberty may occur in boys with testicular sex-cord tumors. PMID:8887151

  2. Permanent and functional male-to-female sex reversal in d-rR strain medaka (Oryzias latipes) following egg microinjection of o,p'-DDT.

    PubMed Central

    Edmunds, J S; McCarthy, R A; Ramsdell, J S

    2000-01-01

    Complete sex reversal of fish is accomplished routinely in aquaculture practices by exposing fish to exogenous sex steroids during gonadal differentiation. A variety of environmental chemicals are also active at sex steroid receptors and theoretically possess the potential to alter normal sexual differentiation in fish. However, in controlled environmental chemical exposures to date, only partial alterations of fish sexual phenotype have been observed. Here we report complete, permanent, and functional male-to-female sex reversal in the Japanese medaka (Oryzias latipes, d-rR strain) after a onetime embryonic exposure to the xenoestrogen o, p'-DDT. d-rR strain medaka are strict gonochorists that possesses both sex-linked pigmentation, which distinguishes genotypic sex, and sexually dimorphic external secondary sexual characteristics, which distinguish phenotypic sex. We directly microinjected the xenoestrogen o, p'-DDT into the egg yolks of medaka at fertilization to parallel the maternal transfer of lipophilic contaminants to the embryo. At 10 weeks of age, microinjected medaka were examined for mortality and sex reversal. A calculated embryonic dose of 511 +/- 22 ng/egg o, p'-DDT (mean +/- standard error) resulted in 50% mortality. An embryonic exposure of 227 +/- 22 ng/egg o, p'-DDT resulted in 86% (6 of 7) sex reversal of genetic males to a female phenotype (XY females). XY females were distinguished by sex-linked male pigmentation accompanying female secondary sexual characteristics. Histologic examination of the gonads confirmed active ovaries in 100% of the XY females. In 10-day breeding trials in which XY females were paired with normal XY males, 50% of the XY females produced fertilized embryos; this represents a comparable breeding success rate to normal XX females. Fertilized eggs produced from XY females hatched to viable larvae. These results clearly indicate that a weakly estrogenic pesticide, o, p'-DDT, when presented during the critical period of gonadal development, can profoundly alter sexual differentiation. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:10706527

  3. Examining the Sociocultural Context of HIV-related Risk Behaviors Among Kathoey (Male-to-female Transgender Women) Sex Workers in Bangkok, Thailand.

    PubMed

    Nemoto, Tooru; Cruz, Taylor; Iwamoto, Mariko; Trocki, Karen; Perngparn, Usaneya; Areesantichai, Chitlada; Suzuki, Sachiko; Roberts, Colin

    2016-01-01

    Kathoey (male-to-female transgender) sex workers (KSW) in Thailand are at high risk for sexually transmitted infections; however, few qualitative studies have been conducted to understand the sociocultural context of engaging in HIV risk behaviors. A total of 24 participants were purposively sampled in Bangkok based on KSW work venues and substance use. Results revealed the importance of participants' understanding of the self in relation to establishing economic independence through sex work, which could then be used to re-establish support from family, who often have not accepted a son's gender transition. Participants linked being kathoey to a belief in fate but did not view engagement in sex work in the same way. Different sex work venues exposed KSW to different risky situations. HIV prevention programs for kathoey must address the importance of economic security and its relation to social support and gender transition within a cultural- and work-environment-specific framework. PMID:26856798

  4. 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

  5. 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

  6. 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

    2015-01-01

    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 0.5C 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 0.5C 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

  7. Sex determination in cattle based on simultaneous amplification of a new male-specific DNA sequence and an autosomal locus using the same primers.

    PubMed

    Weikard, R; Kühn, C; Brunner, R M; Roschlau, D; Pitra, C; Laurent, P; Schwerin, M

    2001-09-01

    A PCR-based method for sex determination of bovine DNA samples and embryo biopsies is presented. Using only one primer pair both the male-specific sequence FBNY (127 bp) and a sex-independent control PCR-fragment, the microsatellite marker FBN17 (136-140 bp) are generated in the same PCR reaction. Synteny mapping assigned the male-specific sequence to bovine chromosome Y (BTA Y), whereas FBN17 was mapped to bovine chromosome 2. Localisation of FBNY on BTA Y was confirmed by fluorescence in hybridisation of two BAC clones containing the male-specific sequence. There was no amplification of the male-specific target sequence FBNY in sheep, pig, goat, mice, man, and several wild species of the tribe Bovini. The bovine male-specific fragment was detected in dilutions containing as little as 10 pg genomic DNA and in blastomeres from embryo biopsies. The PCR assay presented here does require neither restriction endonuclease digestion of the PCR product nor additional nested PCR steps. Owing to the advantage of parallel amplification of the autosomal locus FBN17 no additional control fragment is necessary to detect PCR failure. The results of sex determination in embryo biopsies using FBNY were in agreement with the outcome from a reference assay used in commercial breeding programs. PMID:11550263

  8. Condom Use with Female Sex Workers among Male Clients in Sichuan Province, China: The Role of Interpersonal and Venue-Level Factors

    PubMed Central

    Latkin, Carl; Luan, Rongsheng; Nelson, Kenrad

    2010-01-01

    Commercial sex work has re-emerged as a widespread industry since China started economic reforms in the 1980s. This study examined the role of interpersonal and venue-level factors in commercial sex male clients' (CSMCs) condom use with female sex workers (FSWs) in China. Given the heterogeneity of commercial sex industry in China, this study also aimed to explore how these factors function differently by social ranks of commercial sex work frequented by CSMCs. A cross-sectional survey was conducted with 601 CSMCs in Sichuan province, China. Human immunodeficiency virus (HIV) prevalence in this sample was 1.7%. In addition to the individual characteristics, interpersonal factor was measured by the frequency of FSWs taking the initiative in condom use and providing condoms. Venue-level factor was assessed by the frequency of the managers of commercial sex venues communicating condom use policies and the frequency of condom availability in commercial sex venues. The primary behavioral outcome was consistent condom use with FSWs. Multivariate logistic regression models revealed that consistent condom use with FSWs was significantly associated with interpersonal (adjusted odds ratio (AOR), 1.62; 95% confidence interval (CI), 1.38, 1.90) and venue-level factors (AOR, 1.98; 95% CI, 1.40, 2.80). Moreover, the associations between interpersonal and venue-level factors and consistent condom use were moderated by social ranks of commercial sex work frequented by the male clients. The present study findings underscore the need for comprehensive HIV prevention approaches that integrate individual, interpersonal, and venue-level factors to reduce HIV risk behaviors among CSMCs in China. PMID:20143269

  9. 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

  10. A Tandem Duplicate of Anti-Müllerian Hormone with a Missense SNP on the Y Chromosome Is Essential for Male Sex Determination in Nile Tilapia, Oreochromis niloticus

    PubMed Central

    Li, Minghui; Sun, Yunlv; Zhao, Jiue; Shi, Hongjuan; Zeng, Sheng; Ye, Kai; Jiang, Dongneng; Zhou, Linyan; Sun, Lina; Tao, Wenjing; Nagahama, Yoshitaka; Kocher, Thomas D.; Wang, Deshou

    2015-01-01

    Variation in the TGF-β signaling pathway is emerging as an important mechanism by which gonadal sex determination is controlled in teleosts. Here we show that amhy, a Y-specific duplicate of the anti-Müllerian hormone (amh) gene, induces male sex determination in Nile tilapia. amhy is a tandem duplicate located immediately downstream of amhΔ-y on the Y chromosome. The coding sequence of amhy was identical to the X-linked amh (amh) except a missense SNP (C/T) which changes an amino acid (Ser/Leu92) in the N-terminal region. amhy lacks 5608 bp of promoter sequence that is found in the X-linked amh homolog. The amhΔ-y contains several insertions and deletions in the promoter region, and even a 5 bp insertion in exonVI that results in a premature stop codon and thus a truncated protein product lacking the TGF-β binding domain. Both amhy and amhΔ-y expression is restricted to XY gonads from 5 days after hatching (dah) onwards. CRISPR/Cas9 knockout of amhy in XY fish resulted in male to female sex reversal, while mutation of amhΔ-y alone could not. In contrast, overexpression of Amhy in XX fish, using a fosmid transgene that carries the amhy/amhΔ-y haplotype or a vector containing amhy ORF under the control of CMV promoter, resulted in female to male sex reversal, while overexpression of AmhΔ-y alone in XX fish could not. Knockout of the anti-Müllerian hormone receptor type II (amhrII) in XY fish also resulted in 100% complete male to female sex reversal. Taken together, these results strongly suggest that the duplicated amhy with a missense SNP is the candidate sex determining gene and amhy/amhrII signal is essential for male sex determination in Nile tilapia. These findings highlight the conserved roles of TGF-β signaling pathway in fish sex determination. PMID:26588702

  11. HIV, Hepatitis C, and Other Sexually Transmitted Infections Among Male Sex Workers in Ho Chi Minh City, Vietnam.

    PubMed

    Colby, Donn J; Oldenburg, Catherine E; Nguyen, Thi; Closson, Elizabeth F; Biello, Katie B; Mayer, Kenneth H; Mimiaga, Matthew J

    2016-04-01

    There is little data on the burden of HIV and other infections that affect male sex workers (MSW) in Vietnam. We conducted behavioral and biological sexual health surveys with 300 MSW in Ho Chi Minh City. Generalized estimating equation models were built to assess factors associated with HIV, hepatitis C, and other sexually transmitted infections (STI). Of 300 MSW, 19 (6.3 %) were diagnosed seropositive for HIV, 11 (3.7 %) had hepatitis C, and 26 (8.7 %) had at least one prevalent STI. In a multivariable model, opiate use was significantly associated with HIV infection (aOR 6.46, 95 % CI 1.28-32.7) and hepatitis C (aOR = 19.6, 95 % CI 2.35-163.6). Alcohol dependency was associated with increased odds of hepatitis C (aOR = 4.79, 95 % CI 1.02-22.5) and decreased odds of other STI (aOR = 0.30, 95 % CI 0.10-0.97). These findings suggest that MSW in Vietnam would benefit from regular HIV and STI testing, as well as linkage to care and substance use rehabilitation services. PMID:26563761

  12. Same sex, no sex, and unaware sex in neurotoxicology.

    PubMed

    Weiss, Bernard

    2011-10-01

    Males and females of virtually all species differ in how they respond to their environment. Because such differences exist in almost all biological realms, including disease patterns and therapeutic outcomes, they have evoked calls by various bodies to incorporate their assessment in research. Neurobehavioral indices pose special questions because, unlike outwardly visible markers, they are described by complex functional outcomes or subtle alterations in brain structure. These divergent responses arise because they are inscribed in the genome itself and then by endocrine mechanisms that govern sexual differentiation of the brain during development and operate throughout life. Other organ systems that exhibit sex differences include the liver, an important consideration for neurotoxicology because it may process many toxic chemicals differentially in males and females. Despite the scope and pervasiveness of sex differences, however, they are disregarded by much of neurotoxicology research. Males predominate in behavioral experiments, few such experiments study both sexes, some investigators fail to even describe the sex of their subjects, and in vitro studies tend to wholly ignore sex, even for model systems aimed at neurological disorders that display marked sex differences. The public is acutely aware of sex differences in behavior, as attested by its appetite for books on the topic. It closely follows debates about the proportion of women in professions that feature science and mathematics. Neurotoxicology, especially in the domain of laboratory research, will be hindered in its ability to translate its findings into human health measures if it assigns sex differences to a minor role. It must also be sensitive to how such debates are framed. Often, the differences evoking the most discussion are subtle in scope. They do not lend themselves to the typical analyses conducted by experimenters; that is, reliance on mean differences and null hypothesis testing. PMID:20875453

  13. Attraction of spathius agrili yang (Hymenoptera: eulophidae) to male-produced "aggregation-sex pheromone:" differences between the sexes and mating status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male and female Spathius agrili Yang were tested for attraction to the synthetic male pheromone. Lures consisting of a 3-component pheromone blend were placed in the center of a white filter paper target used to activate upwind flight in the wind tunnel. When virgin males and females were tested for...

  14. Male and Female--The Mutually Disadvantaged: The School Psychologist's Role in Expanding Options for Both Sexes

    ERIC Educational Resources Information Center

    Engin, Ann; And Others

    1973-01-01

    Discusses the sexism inherent in the socialization of boys and girls by reviewing some of the research on sex differences in intellectual functioning, stereotypic sex roles, and sexism in the schools. Suggests ways in which school psychologists can help effect the liberation of both sexes. (SF)

  15. 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

  16. 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

    Hwahng, Sel Julian; Nuttbrock, Larry

    2007-12-01

    This article describes 3 distinct ethnocultural male-to-female transgender communities in New York City: the low-income African American/Black 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. PMID:19079558

  17. Experimental reduction of intromittent organ length reduces male reproductive success in a bug.

    PubMed

    Dougherty, Liam R; Rahman, Imran A; Burdfield-Steel, Emily R; Greenway, E V Ginny; Shuker, David M

    2015-06-01

    It is now clear in many species that male and female genital evolution has been shaped by sexual selection. However, it has historically been difficult to confirm correlations between morphology and fitness, as genital traits are complex and manipulation tends to impair function significantly. In this study, we investigate the functional morphology of the elongate male intromittent organ (or processus) of the seed bug Lygaeus simulans, in two ways. We first use micro-computed tomography (micro-CT) and flash-freezing to reconstruct in high resolution the interaction between the male intromittent organ and the female internal reproductive anatomy during mating. We successfully trace the path of the male processus inside the female reproductive tract. We then confirm that male processus length influences sperm transfer by experimental ablation and show that males with shortened processi have significantly reduced post-copulatory reproductive success. Importantly, male insemination function is not affected by this manipulation per se. We thus present rare, direct experimental evidence that an internal genital trait functions to increase reproductive success and show that, with appropriate staining, micro-CT is an excellent tool for investigating the functional morphology of insect genitalia during copulation. PMID:25972470

  18. The histone demethylase Dmel\\Kdm4A controls genes required for life span and male-specific sex determination in Drosophila.

    PubMed

    Lorbeck, Meridith T; Singh, Neetu; Zervos, Ashley; Dhatta, Madhusmita; Lapchenko, Maria; Yang, Chen; Elefant, Felice

    2010-01-15

    Histone methylation plays an important role in regulating chromatin-mediated gene control and epigenetic-based memory systems that direct cell fate. Enzymes termed histone demethylases directly remove the methyl marks from histones, thus contributing to a dynamically regulated histone methylated genome; however, the biological functions of these newly identified enzymes remain unclear. The JMJD2A-D family belongs to the JmjC domain-containing family of histone demethylases (JHDMs). Here, we report the cloning and functional characterization of the Drosophila HDM gene Dmel\\Kdm4A that is a homolog of the human JMJD2 family. We show that homologs for three human JHDM families, JHDM1, JHDM2, and JMJD2, are present in Drosophila and that each is expressed during the Drosophila lifecycle. Disruption of Dmel\\Kdm4A results in a reduction of the male life span and a male-specific wing extension/twitching phenotype that occurs in response to other males and is reminiscent of an inter-male courtship phenotype involving the courtship song. Remarkably, certain genes associated with each of these phenotypes are significantly downregulated in response to Dmel\\Kdm4A loss, most notably the longevity associated Hsp22 gene and the male sex-determination fruitless gene. Our results have implications for the role of the epigenetic regulator Dmel\\Kdm4A in the control of genes involved in life span and male-specific sex determination in the fly. PMID:19786080

  19. 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

  20. 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

  1. Social influences on physical activity in Anglo- and Vietnamese-Australian adolescent males in a single sex school.

    PubMed

    Wilson, Andrew N; Dollman, James

    2007-06-01

    Understanding factors that influence physical activity levels of adolescents can assist the design of more effective interventions. Social support is a consistent correlate of youth physical activity but few studies have examined this in different cultural settings. Male adolescents (n=180, age=13.58+/-0.97 years) from a metropolitan single sex private school participated in this study. Habitual physical activity was estimated using the 3-day physical activity recall (3dPAR), and aspects of social support to be physically active using a specifically designed questionnaire. Comparisons were made between Anglo-Australians (n=118), whose parents were both born in Australia, and Vietnamese-Australians (n=62), whose parents were both born in Vietnam. There was a trend towards higher physical activity among Anglo-Australians, particularly on weekends. Anglo-Australians reported significantly more parental and peer support across most items pertaining to these constructs. Among the whole sample, social support variables explained 5-12% of the total explained variance in physical activity, with items pertaining to father and best friend support emerging as the strongest and most consistent predictors in multiple regression models. Among Anglo-Australians, the prediction models were relatively weak, explaining 0-9% of the total explained variance in physical activity. Prediction models for physical activity among Vietnamese-Australians were much stronger, explaining 11-32% of the total explained variance, with father's support variables contributing consistently to these models. The strong paternal influence on physical activity among Vietnamese-Australians needs to be confirmed in more diverse population groups, but results from this study suggest that interventions promoting physical activity among adolescent boys need to take into account cultural background as a moderator of widely reported social influences. PMID:16844412

  2. 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-Ccile; Siaussat, David; Debernard, Stphane; 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

  3. Peri-pubertal administration of 3-nitro-1,2,4-triazol-5-one (NTO) affects reproductive organ development in male but not female Sprague Dawley rats.

    PubMed

    Lent, Emily May; Crouse, Lee C B; Wallace, Shannon M; Carroll, Erica E

    2015-11-01

    Nitrotriazolone (3-nitro-1,2,4-triazol-5-one; NTO) is an insensitive munition that has demonstrated effects on reproductive organs in adult male rats. NTO was administered to male (0, 250, and 500milligrams per kilogram per day (mg/kg-day)) and female (0, 500, and 1000mg/kg-day) Sprague-Dawley rats (15/sex/group) via oral gavage from weaning through post-natal day 53/54 and 42/43, respectively. Age and body mass at vaginal opening (VO) and preputial separation (PPS), as well as all measures of estrous cyclicity were not affected by treatment with NTO. Males treated with NTO exhibited reductions in testis mass associated with tubular degeneration/atrophy. Less pronounced reductions in accessory sex organ masses were also observed in the 500mg/kg-day group. Treatment with NTO did not affect thyroid hormone or testosterone levels. These findings suggest that NTO is not acting as an estrogen or thyroid active compound, but may indicate effects on steroidogenesis and/or direct testicular toxicity. PMID:25962730

  4. The chastity of amoebae: re-evaluating evidence for sex in amoeboid organisms

    PubMed Central

    Lahr, Daniel J. G.; Parfrey, Laura Wegener; Mitchell, Edward A. D.; Katz, Laura A.; Lara, Enrique

    2011-01-01

    Amoebae are generally assumed to be asexual. We argue that this view is a relict of early classification schemes that lumped all amoebae together inside the ‘lower’ protozoa, separated from the ‘higher’ plants, animals and fungi. This artificial classification allowed microbial eukaryotes, including amoebae, to be dismissed as primitive, and implied that the biological rules and theories developed for macro-organisms need not apply to microbes. Eukaryotic diversity is made up of 70+ lineages, most of which are microbial. Plants, animals and fungi are nested among these microbial lineages. Thus, theories on the prevalence and maintenance of sex developed for macro-organisms should in fact apply to microbial eukaryotes, though the theories may need to be refined and generalized (e.g. to account for the variation in sexual strategies and prevalence of facultative sex in natural populations of many microbial eukaryotes). We use a revised phylogenetic framework to assess evidence for sex in several amoeboid lineages that are traditionally considered asexual, and we interpret this evidence in light of theories on the evolution of sex developed for macro-organisms. We emphasize that the limited data available for many lineages coupled with natural variation in microbial life cycles overestimate the extent of asexuality. Mapping sexuality onto the eukaryotic tree of life demonstrates that the majority of amoeboid lineages are, contrary to popular belief, anciently sexual, and that most asexual groups have probably arisen recently and independently. Additionally, several unusual genomic traits are prevalent in amoeboid lineages, including cyclic polyploidy, which may serve as alternative mechanisms to minimize the deleterious effects of asexuality. PMID:21429931

  5. 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

  6. 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 < 0.05). FSWs with regular 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

  7. The disproportionate burden of HIV and STIs among male sex workers in Mexico City and the rationale for economic incentives to reduce risks

    PubMed Central

    Galárraga, Omar; Sosa-Rubí, Sandra G; González, Andrea; Badial-Hernández, Florentino; Conde-Glez, Carlos J; Juárez-Figueroa, Luis; Bautista-Arredondo, Sergio; Kuo, Caroline; Operario, Don; Mayer, Kenneth H

    2014-01-01

    Introduction The objective of this article is to present the rationale and baseline results for a randomized controlled pilot trial using economic incentives to reduce HIV and sexually transmitted infection (STI) risk among male sex workers (MSWs) in Mexico City. Methods Participants (n=267) were tested and treated for STIs (chlamydia, gonorrhoea, syphilis and HIV) and viral hepatitis (hepatitis B and C), received HIV and STI prevention education and were randomized into four groups: (1) control, (2) medium conditional incentive ($50/six months), (3) high conditional incentive ($75/six months) and (4) unconditional incentive ($50/six months). In the conditional arms, incentives were contingent upon testing free of new curable STIs (chlamydia, gonorrhoea and syphilis) at follow-up assessments. Results Participants’ mean age was 25 years; 8% were homeless or lived in a shelter, 16% were unemployed and 21% lived in Mexico City less than 5 years. At baseline, 38% were living with HIV, and 32% tested positive for viral hepatitis or at least one STI (other than HIV). Participants had a mean of five male clients in the previous week; 18% reported condomless sex with their last client. For 37%, sex work was their main occupation and was conducted mainly on the streets (51%) or in bars/discotheques (24%) and hotels (24%). The average price for a sex transaction was $25 with a 35% higher payment for condomless sex. Conclusions The findings suggest that economic incentives are a relevant approach for HIV prevention among MSWs, given the market-based inducements for unprotected sex. This type of targeted intervention seems to be justified and should continue to be explored in the context of combination prevention efforts. PMID:25399543

  8. Debe cuidarse en la calle: Normative influences on condom use among the steady male partners of female sex workers in the Dominican Republic

    PubMed Central

    Barrington, Clare; Kerrigan, Deanna

    2014-01-01

    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 eleven steady male partners of female sex workers; participants completed 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

  9. Weight and season affects androstenone and skatole occurrence in entire male pigs in organic pig production.

    PubMed

    Thomsen, R; Edwards, S A; Jensen, B B; Rousing, T; Srensen, J T

    2015-09-01

    To investigate the extent to which the level of androstenone and skatole decreases with a decrease in live weight and/or age at slaughter of entire male pigs produced under organic standards, 1174 entire male pigs were raised in parallel in five organic herds, distributed across four batches in summer and winter. The median androstenone level was high for organic entire male pigs (1.9 g/g), but varied greatly both within and between herds. Median skatole level was 0.05 g/g, also with a wide range both within and between herds. Decreasing live weight over the range of 110 15.6 kg s.d. was found to decrease androstenone as well as skatole concentration, however, with different patterns of association. Age did not have significant direct effect on either androstenone or skatole levels. Androstenone levels were higher during winter than summer (P<0.0001), but no difference in skatole was found between seasons. The study concludes that decreasing live weight at slaughter could be an applicable management tool to reduce risk of boar taint and the level of tainted carcasses for a future production of entire male pigs within the organic pig production system, although further studies are needed as great variation in boar taint was found also for low weight animals. PMID:25990807

  10. Direct and indirect effects of a sex-biased antagonist on male and female fertility: consequences for reproductive trait evolution in a gender-dimorphic plant.

    PubMed

    Ashman, Tia-Lynn; Penet, Laurent

    2007-05-01

    Gender-dimorphic plants are often subject to sex-differential enemy attack, but whether and how this contributes to trait evolution is unknown. To address this gap, we documented the spatiotemporal prevalence of sex-biased weevil damage in a gynodioecious strawberry. We then conducted path analysis to evaluate the direct and indirect pathways for weevils to affect female and male fertility and to mediate selection in two experimental gardens. Direct effects of weevils significantly reduced fertility and mediated selection on reproductive traits, even in the nonpreferred sex (females). Weevils significantly reduced floral display size in hermaphrodites in both gardens, and this translated into a substantial negative indirect effect on male fertility in the garden where the pathway to fertility via display was stronger. Thus, indirect effects of weevils can contribute to selection in hermaphrodites, which gain the majority of their fitness via male function. Our results also indicate that weevils often play a larger role than pollinators in shaping reproductive phenotype and thus raise the intriguing possibility that antagonists may be drivers of sexual dimorphism. Finally, our results support the view that mutualists, antagonists, and the abiotic environment should be considered when attempting to understand reproductive trait evolution in gender-dimorphic species. PMID:17427131

  11. Sex-linked recessive

    MedlinePLUS

    Inheritance - sex-linked recessive; Genetics - sex-linked recessive; X-linked recessive ... X-linked recessive diseases usually occur in males. Males have only one X chromosome. A single recessive ...

  12. Perceptions of Female and Male Superintendents for a Middle School Principalship as Moderated by Sex and National Origin of Applicants

    ERIC Educational Resources Information Center

    Young, Phillip; Young, Karen Holsey

    2010-01-01

    A 2 x 2 x 2 factorial design involving sex of superintendents, sex of applicants, and national origin of applicants (Hispanic vs. non-Hispanic) is used to assess screening decisions for a middle school principalship. Screening decisions are analyzed from a sequential model to capture selection as a process. Results indicate that biases surface…

  13. Perceptions of Female and Male Superintendents for a Middle School Principalship as Moderated by Sex and National Origin of Applicants

    ERIC Educational Resources Information Center

    Young, Phillip; Young, Karen Holsey

    2010-01-01

    A 2 x 2 x 2 factorial design involving sex of superintendents, sex of applicants, and national origin of applicants (Hispanic vs. non-Hispanic) is used to assess screening decisions for a middle school principalship. Screening decisions are analyzed from a sequential model to capture selection as a process. Results indicate that biases surface

  14. Sex Roles Inside the Corporation. A Summary of Findings from Mgmt. 689: "Special Topics in Careers & Sex Roles in the Organization".

    ERIC Educational Resources Information Center

    Greenfeld, Sue

    Advanced graduate students enrolled in a management course conducted thirty-four structured interviews at a major multi-million-dollar Houston-based oil company. Approximately fifty open-ended questions were asked the respondents over topics related to sex roles in the organization, including employee interactions, secretarial roles, work-related

  15. Expression profile of doublesex/male abnormal-3-related transcription factor-1 during gonadal sex change in the protogynous wrasse, Halichoeres trimaculatus.

    PubMed

    Nozu, Ryo; Horiguchi, Ryo; Kobayashi, Yasuhisa; Nakamura, Masaru

    2015-11-01

    Sex change in fish involves a dramatic transformation of gonadal tissue and a switch in gametogenesis. Doublesex/male abnormal-3-related transcription factor-1 (DMRT1), encoded by the DMRT1 gene, is involved in testicular differentiation in a wide range of vertebrates as well as in sexual differentiation and gonadal sex change. In the present study, we investigated changes in the expression of dmrt1 during artificial gonadal sex change in the three-spot wrasse, Halichoeres trimaculatus, by real-time quantitative PCR and immunolocalization, using an anti-wrasse-Dmrt1 antibody that we prepared. We found that dmrt1 expression was predominantly observed in the testes, and that Dmrt1 was expressed in Sertoli cells of testes and a few granulosa cells surrounding vitellogenic oocytes of the ovary. Additionally, the upregulation of dmrt1 expression was consistent with an increase in spermatogenic cyst quantity rather than proliferation of presumptive spermatogonia, suggesting that dmrt1 is involved in the progression of spermatogenesis during sex change. Changes in the localization of Dmrt1 during gonadal sex change further implied that Sertoli cells originate from somatic cells adjacent to gonial germ cells during testicular formation in the three-spot wrasse. Mol. Reprod. Dev. 82: 859-866, 2015. 2015 Wiley Periodicals, Inc. PMID:26202688

  16. Non-defendable resources affect peafowl lek organization: a male removal experiment.

    PubMed

    Loyau, Adeline; Jalme, Michel Saint; Sorci, Gabriele

    2007-01-10

    A lekking mating system is typically thought to be non-resource based with male providing nothing to females but genes. However, males are thought to clump their display sites on areas where they are more likely to encounter females, which may depend on non-defendable resource location. We tested this hypothesis on a feral population of peacocks. In agreement, we found that, within the lek, display site proximity to food resources had an effect on female visitation rate and male mating success. The attractiveness of display sites to male intruders was explained by the distance to the feeding place and by the female visitation rate. We randomly removed 29 territorial males from their display sites. Display sites that were more attractive to male intruders before removal remained highly attractive after removal and display sites closer to the feeding area attracted the attention of intruders significantly more after removal. Similarly, display sites that were more visited by females before removal remained more visited after removal, suggesting again that the likelihood of encountering females is determined by the display site location. Overall, these results are in agreement with non-defendable resources affecting lek spatial organization in the peafowl. PMID:17074448

  17. 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

  18. Where did all the Aleut men go? Aleut male attrition and related patterns in Aleutian historical demography and social organization.

    PubMed

    Reedy-Maschner, Katherine

    2010-12-01

    Historical, economic, and political influences on Aleut demography and social organization are considered in relation to an apparent deficit of Aleut males in the early 20th century. Ethnohistoric records detail persistent waves of explorers, fur hunters, missionaries, bureaucrats, and foreign fishermen coming to the Aleutian region for economic exploitation, with some making it their home. The first major wave consisted of Russian and Siberian crews in pursuit of sea otters and fur seals. These entrepreneurs moved Aleut men to hunting grounds and replaced a large portion of them in the villages. The second wave consisted of Scandinavian and other European immigrants who followed cod, halibut, and herring fisheries and who married into eastern Aleut villages. These movements resulted in two genealogical deficits of Aleut men with concomitant shifts in social organization and economic emphases that contribute to the modern diversity of Aleut society. Aleut evacuation during World War II exacerbated these sex imbalances in the villages of the western Aleutian and Pribilof islands. PMID:21417885

  19. Acceptability of vaginal microbicides among female sex workers and their intimate male partners in two Mexico-US border cities: a mixed methods analysis.

    PubMed

    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

    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 Jurez, Mexico, where HIV prevalence is increasing. FSWs and their verified intimate (non-commercial) male partners completed quantitative and qualitative interviews from 2010 to 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. 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 one in six 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 conflicts causing injury within relationships among men. 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

  20. 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

  1. 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

  2. Spermatogenesis, epididymis morphology and plasma sex steroid secretion in the male lizard Podarcis sicula exposed to diuron.

    PubMed

    Cardone, Anna; Comitato, Raffaella; Angelini, Francesco

    2008-10-01

    The present study investigates the effects of diuron, a substituted urea-based herbicide, in the male lizard Podarcis sicula utilizing quantitative and qualitative morphological features of the reproductive system and endocrinological analysis. Besides the control group, lizards were divided into three groups ([a-c]) (n=6/group) and placed for 3 weeks in terraria on polluted soil substrate sprayed with 3.75 L/ha of herbicide Toterbane 50F (50% diuron). Each terrarium was supplemented either with drinking water contaminated by herbicide (i.e. 1.08 microg/mL of diuron; group [a]), or with food contaminated by herbicide (i.e. 5.4 mg of diuron; group [b]), or with drinking water and food contaminated as described above (group [c]). None of the animals exposed to the contaminant showed any signs of general toxicity or death during the course of the experiments. Severe testicular effects are evidenced in all herbicide-treated groups, although, such effects are of a greater magnitude in lizards exposed to contaminated water (groups [a] and [c]). The main degenerative changes observed include: (1) a significant decrease in the mean gonadosomatic index of 55% in group [a] (P<0.001), 21% in group [b] (P<0.01) and 34% in group [c] (P<0.001) compared with control group; (2) a significant shrinking (P<0.001) of seminiferous tubule diameter (more than 60% of the control) in groups [a] and [c], and about 18% in group [b] (P<0.01); (3) a significant decrease in the crude numbers of spermatogonia of 92% in group [a] (P<0.001), 27% in group [b] (P<0.01) and 62% in group [c] (P<0.001) compared with control group. A complete loss of meiotic and mature germ cells in groups [a] and [c], and a reduction of primary spermatocytes, secondary spermatocytes and spermatids (more than 27% of the control) and a decrease of spermatozoa (more than 90% of the control) in group [b]; and (4) an hypertrophy of interstitial connective tissue which contains numerous lymphocytes, neutrophils and monocytes. The decrease and/or loss of germ cells seems to be related to an induction of inflammation (necrosis) rather than to apoptotic processes. Indeed, this hypothesis is supported by a TUNEL-assay, which failed to reveal any apoptotic cells either in the seminiferous epithelium or in the interstitial space in the testis of all exposed groups. Also the epididymis appears affected by diuron exposure. In particular, in experimental groups [a] and [c] it is regressed with abundant connective tissue and low epithelial cells without secretory granules, whereas in group [b] it appears partially regressed, with some secretory granules still present. At the same time, an impairment of the plasma sex-hormone levels is observed in treated lizards, as evidenced by RIA analysis. Testosterone values significantly decreased by 43% in group [a] (P<0.001), 34% in group [b] (P<0.01) and 52% in group [c] compared with control group. Instead, 17beta-estradiol plasma content is undetectable in all diuron-exposed lizards. Taken together, the results presented here indicate that diuron exposure resulted in direct male reproductive toxicity and reveal that this lizard is suitable as a laboratory reptile species for toxicological investigations. PMID:18760409

  3. 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.

    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.

  4. Organ doses for reference adult male and female undergoing computed tomography estimated by Monte Carlo simulations

    PubMed Central

    Lee, Choonsik; Kim, Kwang Pyo; Long, Daniel; Fisher, Ryan; Tien, Chris; Simon, Steven L.; Bouville, Andre; Bolch, Wesley E.

    2011-01-01

    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 phantoms Methods: 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. PMID:21520832

  5. Safe sex: male-female coalitions and pre-copulatory mate-guarding in a fiddler crab.

    PubMed

    Milner, Richard N C; Jennions, Michael D; Backwell, Patricia R Y

    2010-04-23

    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

  6. 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.

  7. A four year study of vasectomy on plasma levels of pituitary and sex hormones in normal males in Sri Lanka.

    PubMed

    Piyasena, R D; Weerasekera, D A; Reginald, G J; Wikramanayake, T W

    1982-03-01

    Blood levels of pituitary gonadotropins, prolactin, testosterone, and estrogens were measured at regular intervals in Sri Lankan males of proven fertility for a period of 4 years after vasectomy. All assays were done by standard radioimmunoassay procedures using materials supplied by the World Health Organization, Geneva, under their Special Program of Research, Development, and Research Training in Human Reproduction (Matched Assay Reagent Program), which also provides for internal and external quality control of results. No significant alteration from basal values of any of the hormonal levels measured was observed over the 4-year period. The results may increase confidence in vasectomy as a means of contraception. The effects of vasectomy on the plasma levels of the abovementioned hormones were investigated over a 4-year period from February 1975. Blood samples were obtained prior to surgery and at regular intervals thereafter for 4 years so that each subject served as his own control. Serum was stored deep frozen and the relevant hormonal measurements made in batches by radioimmunoassay techniques with suitable precautions for both internal and external quality control. PMID:7151239

  8. Male or female, we will create them: the ethics of sex selection for non-medical reasons.

    PubMed

    Heyd, David

    2003-01-01

    The article examines the arguments for and against the practice of sex selection for non-medical reasons (e.g. parental preferences, family balancing, religious reasons) in light of the new technology of Preimplantation Genetic Diagnosis (PGD). It distinguishes between arguments about the risks to the future child, the mother and society, on the one hand, and the inherent wrongness of the practice as an illegitimate interference in the natural course of reproduction, on the other. The article tries to show that at least in the well defined context of sex selection by PGD, when IVF was performed for independent medical reasons, there is no danger to either the child or the mother and hence that the practice should be permitted. Furthermore, the alleged dangers to society are demonstrated to be mostly illusory. On the one hand, the demographic danger is usually overstated and lacks historical support. On the other hand, the feminist claim that sex selection is necessarily discriminatory is found to be both theoretically and empirically groundless. The article's conclusion is that despite widespread intuitive objection to the practice of sex selection, it can be justified in terms of parental autonomy and falls within the value of family planning. This liberal view does not, however, imply that having a child of the desired sex is the parents' right, nor does it apply to sex selection in later phases of gestation (abortions and obviously, infanticide). PMID:16206460

  9. Sex and Sex-Role Identification: An Important Distinction for Organizational Research.

    ERIC Educational Resources Information Center

    Powell, Gary N.; Butterfield, R. Anthony

    Studies which have investigated males' and females' attitudes and behavior in organizations have yielded apparently contradictory results. In some studies, individuals have followed traditional sex-role stereotypes; in others, they have not. A proposed explanation for these inconsistencies is that sex-role identification is a more important…

  10. 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

  11. Alteration of serum sex hormonal profile in male gasoline filling station workers in respect to their polymorphism of glutathione S-transferase M1.

    PubMed

    Saadat, Mostafa; Bahaoddini, Samaneh; Saadat, Iraj

    2013-03-01

    Alterations in offspring sex ratio at birth and level of serum testosterone in filling-station workers have been reported. To determine the association of glutathione S-transferase M1 (GSTM1) polymorphism with serum levels of total testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) of male filling-station workers, the present study was carried out on 114 gasoline workers and 100 age- and sex-matched controls with no occupational exposure to gasoline. We have found no significant difference between the workers and controls for levels of sex hormones in the presence of active GSTM1 genotype. Among subjects with the GSTM1 null genotype, there was significant difference between exposed and unexposed subjects for the concentration of testosterone (t=4.37, df=97, P<0.001). To investigate whether one null genotype could be compensated by an active genotype for the other isoenzyme, the mean concentrations of sex hormones was compared between the exposed and control groups with respect to their combinations of the GSTM1 and GSTT1 genotypes. The exposed group having either "null GSTM1/positive GSTT1" (t=2.76, df=72, P=0.007) or "null GSTM1/null GSTT1" (t=4.91, df=23, P<0.001) combinations had a lower testosterone compared with the controls. It seems that GSTM1 polymorphism has more effect on serum testosterone compared to the GSTT1 polymorphism, in exposed workers. PMID:23357602

  12. Prevalence and Predictors of Self-Reported Consistent Condom Usage among Male Clients of Female Sex Workers in Tamil Nadu, India.

    PubMed

    Rastogi, Saumya; Charles, Bimal; Sam, Asirvatham Edwin

    2014-01-01

    Clients of female sex workers (FSWs) possess a high potential of transmitting HIV and other sexually transmitted infections from high risk FSWs to the general population. Promotion of safer sex practices among the clients is essential to limit the spread of HIV/AIDS epidemic. The aim of this study is to estimate the prevalence of consistent condom use (CCU) among clients of FSWs and to assess the factors associated with CCU in Tamil Nadu. 146 male respondents were recruited from the hotspots who reportedly had sex with FSWs in exchange for cash at least once in the past one month. Data were analyzed using bivariate and multivariate methods. Overall, 48.6 and 0.8 percent clients consistently used condoms in the past 12 months with FSWs and regular partners, respectively. Logistic regression showed that factors such as education, peers' use of condoms, and alcohol consumption significantly influenced clients' CCU with FSWs. Strategies for safe sex-behaviour are needed among clients of FSWs in order to limit the spread of HIV/AIDS epidemic in the general population. The role of peer-educators in experience sharing and awareness generation must also be emphasized. PMID:26316978

  13. Just getting by: A cross-sectional study of male sex workers as a most-at-risk population for HIV/STIs among men who have sex with men in Peru

    PubMed Central

    Bayer, Angela M.; Garvich, Mijail; Daz, David A.; Snchez, Hugo; Garca, Patricia J.; Coates, Thomas J.

    2014-01-01

    Objectives To describe the socio-demographic and sex work characteristics, recent sexual practices, HIV risk perception and testing history, and HIV and syphilis prevalences of Cercado (downtown) and non-Cercado (close urban) male sex workers (MSWs) in Lima, Peru. Methods Eighty-nine MSWs completed a self-administered survey and participated in HIV and syphilis testing. Results Cercado MSWs had significantly lower median weekly earnings than non-Cercado MSWs (US $43 versus $72, p=0.04). Most non-Cercado MSWs (81%) reported only insertive anal intercourse with male/transgender partners, while Cercado MSWs primarily reported only insertive (52%) or both insertive and receptive (45%) anal intercourse (p=0.03). Consistent condom use was low with insertive and receptive anal intercourse in both sub-groups. Among MSWs with recent female partners, condom use with the last partner was lower among Cercado versus non-Cercado MSWs for vaginal sex (37% versus 65%, p=0.04) and anal sex (27% versus 80%, p=0.01). More Cercado than non-Cercado MSWs (57% versus 42%) perceived high HIV risk (p=0.05) and Cercado MSWs had a much higher prevalence than non-Cercado MSWs of HIV [23% versus 4% (p = 0.04)] and syphilis [22% versus 0% (p = 0.02)] infections. Conclusion MSWs in Lima are diverse and Cercado MSWs are just getting by, engaging in more risk behaviors, and more likely to have HIV/STIs. Future research should identify, describe and HIV/STI test broader groups of MSWs and their client and non-client partners. Prevention efforts should provide HIV/STI risk reduction education for MSWs and related sub-groups who are currently not targeted such as female partners. PMID:24391061

  14. 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.

  15. Men Who Report Recent Male and Female Sex Partners in Cape Town, South Africa: An Understudied and Underserved Population

    PubMed Central

    Eaton, Lisa A.; Pitpitan, Eileen V.; Kalichman, Seth C.; Sikkema, Kathleen J.; Skinner, Donald; Watt, Melissa H.; Pieterse, Desiree

    2013-01-01

    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 four 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

  16. Sex difference in whole-body androgen content in rats on fetal days 18 and 19 without evidence that androgen passes from males to females.

    PubMed

    Baum, M J; Woutersen, P J; Slob, A K

    1991-05-01

    The whole-body content of androgen (testosterone + 5 alpha-dihydrotestosterone) was significantly higher on Fetal Days 18 and 19 in male than in female rats; androgen content was equivalent in the two sexes at other fetal ages, including Days 16, 17, 20, and 21, and prior to parturition on Fetal Day 22. These results partially corroborate previous data of Weisz and Ward (Endocrinology 1980; 106:306-316), who measured testosterone in pooled plasma from rat fetuses and suggest that androgens contribute to masculine brain sexual differentiation only briefly during fetal life. No significant differences in whole-body androgen content were observed among groups of females situated in utero between 0, 1, or 2 males on each side (contiguous male model) or among groups of females with 0, 1, or 2 or more males located caudally (on the cervical side) in the same uterine horn, regardless of whether combined data from Fetal Days 17-22 or only Fetal Days 18 and 19 were considered. These results provide no evidence that androgens from males reach female fetuses in the same uterine horn. PMID:1868134

  17. Medfly (Diptera: Tephritidae) genetic sexing: large-scale field comparison of males-only and bisexual sterile fly releases in Guatemala.

    PubMed

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

    2004-10-01

    The effect of releases of bisexual (males and female) and unisexual (male only) sterilized medflies was compared in three large field evaluations over a 3-yr period (1995-1997) 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 were mass-reared, sterilized by irradiation as pupae, shipped to a field center, and released by air as young adults over 2 km by 2 km core areas in the centers of separate 6 km by 6 km test plots. Strain performance was monitored weekly by trapping sterile and wild male adults in core and buffer areas and by collecting eggs from coffee berries to determine induced sterility. Results indicated a several-fold advantage for the males-only strain as measured by the level of induced sterility, especially at the very high release ratios of 100:1 recorded in 1997. During that final test year, sterile-fly release rates were increased to provide high sterile:wild (S:W) fly ratios in the field, and egg sterility reached levels in excess of 70% in plots were the male-only strain was used. However, in the plots where the bisexual strain was released, induced sterility only reached 12% despite S:W ratios above 1,000:1. PMID:15568342

  18. 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)

  19. Morphology of the external genitalia of the adult male and female mice as an endpoint of sex differentiation.

    PubMed

    Weiss, Dana A; Rodriguez, Esequiel; Cunha, Tristan; Menshenina, Julia; Barcellos, Dale; Chan, Lok Yun; Risbridger, Gail; Baskin, Laurence; Cunha, Gerald

    2012-05-01

    Adult external genitalia (ExG) are the endpoints of normal sex differentiation. Detailed morphometric analysis and comparison of adult mouse ExG has revealed 10 homologous features distinguishing the penis and clitoris that define masculine vs. feminine sex differentiation. These features have enabled the construction of a simple metric to evaluate various intersex conditions in mutant or hormonally manipulated mice. This review focuses on the morphology of the adult mouse penis and clitoris through detailed analysis of histologic sections, scanning electron microscopy, and three-dimensional reconstruction. We also present previous results from evaluation of "non-traditional" mammals, such as the spotted hyena and wallaby to demonstrate the complex process of sex differentiation that involves not only androgen-dependent processes, but also estrogen-dependent and hormone-independent mechanisms. PMID:21893161

  20. 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 (20092010), 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 1860?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

  1. Sex Differences in Somatotrope Dependency on Leptin Receptors in Young Mice: Ablation of LEPR Causes Severe Growth Hormone Deficiency and Abdominal Obesity in Males.

    PubMed

    Allensworth-James, Melody L; Odle, Angela; Haney, Anessa; Childs, Gwen

    2015-09-01

    Leptin receptor (LEPR) signaling controls appetite and energy expenditure. Somatotrope-specific deletion of the LEPRb signaling isoform causes GH deficiency and obesity. The present study selectively ablated Lepr exon 1 in somatotropes, which removes the signal peptide, causing the loss of all isoforms of LEPR. Excision of Lepr exon 1 was restricted to the pituitary, and mutant somatotropes failed to respond to leptin. Young (2-3 mo) males showed a severe 84% reduction in serum GH levels and more than 60% reduction in immunolabeled GH cells compared with 41%-42% reductions in GH and GH cells in mutant females. Mutant males (35 d) and females (45 d) weighed less than controls and males had lower lean body mass. Image analysis of adipose tissue by magnetic resonance imaging showed that young males had a 2-fold increase in abdominal fat mass and increased adipose tissue density. Young females had only an overall increase in adipose tissue. Both males and females showed lower energy expenditure and higher respiratory quotient, indicating preferential carbohydrate burning. Young mutant males slept less and were more restless during the dark phase, whereas the opposite was true of females. The effects of a Cre-bearing sire on his non-Cre-recombinase bearing progeny are seen by increased respiratory quotient and reduced litter sizes. These studies elucidate clear sex differences in the extent to which somatotropes are dependent on all isoforms of LEPR. These results, which were not seen with the ablation of Lepr exon 17, highlight the severe consequences of ablation of LEPR in male somatotropes. PMID:26168341

  2. Meeting the Needs of Male Caregivers by Increasing Access to Accountable Care Organizations.

    PubMed

    Schwartz, Abby J; McInnis-Dittrich, Kathleen

    2015-01-01

    As the population of male caregivers continues to grow over time, they have become more visible to the service system. However, as the vast majority of supports serve female caregivers, it is important to bring men "inside" of the service system. Following a review of the male caregiver experience, this commentary discusses how Accountable Care Organizations (ACOs), a provision of the Patient Protection and Affordable Care Act of 2010, is one way that men can be brought into and access the service system. Although male caregivers are the focus of this paper, the recommendations suggested are useful for professionals working with all caregivers regardless of gender. Discussion includes a rationale as to why ACOs are a unique service that are currently being developed that provides a window of opportunity for health professionals to meet caregiver needs in new ways. This would include the evaluation of and addressing male caregiver psychosocial and support needs at the time of addressing care receivers' medical needs. PMID:26207698

  3. Exploration of functional health, mental well-being and cross-sex hormone use in a sample of Thai male-to-female transgendered persons (kathoeys).

    PubMed

    Gooren, Louis J; Sungkaew, Tanapong; Giltay, Erik J

    2013-03-01

    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 (9.76.1 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

  4. 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 (9.76.1 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

  5. Early male partnership patterns, social support, and sexual risk behavior among young men who have sex with men

    PubMed Central

    Glick, Sara Nelson; Golden, Matthew R.

    2014-01-01

    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 1630) into a one-year cohort study with serial online retrospective surveys and HIV/STI testing. The first 3 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

  6. Are Apparent Sex Differences in Mean IQ Scores Created in Part by Sample Restriction and Increased Male Variance?

    ERIC Educational Resources Information Center

    Dykiert, Dominika; Gale, Catharine R.; Deary, Ian J.

    2009-01-01

    This study investigated the possibility that apparent sex differences in IQ are at least partly created by the degree of sample restriction from the baseline population. We used a nationally representative sample, the 1970 British Cohort Study. Sample sizes varied from 6518 to 11,389 between data-collection sweeps. Principal components analysis of

  7. The Effects of the Determinants of Women's Movement Into and Out of Male-dominated Occupations on Occupational Sex Segregation.

    ERIC Educational Resources Information Center

    Sheridan, Jennifer T.

    Although occupational sex segregation has decreased over the last 25 years, it is still a major social concern primarily because of the role it plays in perpetuating the gender wage gap. This paper uses data from the Wisconsin Longitudinal Study, a study that followed a random sample of 10,317 high school graduates, to assess the determinants of

  8. Localization of /sup 3/H-estradiol in the reproductive organs of male and female baboons

    SciTech Connect

    Weaker, F.J.; Sheridan, P.J.

    1982-05-01

    The uptake and retention of radiolabeled estradiol by both the male and female reproductive organs were examined in the baboon. Two male and two female baboons were injected intracardially with 1 microgram/kg body weight of /sup 3/H-estradiol and two animals, one male and one female, were injected with both labeled and 100 micrograms/kg body weight of unlabeled estradiol. One and a half hours after the injections, the animals were sacrificed and the uterus, cervix, vagina, oviduct, seminal vesicles, and prostate gland were removed and processed for autoradiography. The stratified squamous epithelia of the cervix and vagina demonstrated a light uptake of the label in the germinative, but not in the superficial cell layers. The columnar cells lining the oviduct and uterine glands were labeled, whereas the luminal epithelium of the uterus and the glandular epithelia of the seminal vesicles and prostate gland did not sequester the tritiated steroid. The interstitial cells of all the organs studied demonstrated a moderate to heavy uptake of the radioactivity, whereas the smooth muscle cells were lightly labeled except in the vagina, in which these cells displayed a moderate number of silver grains.

  9. Evolutionary biology: sex change and relative body size in animals.

    PubMed

    Buston, Peter M; Munday, Philip L; Warner, Robert R

    2004-04-01

    Organisms that change sex during their lifetime use a variety of strategies--they may be female first, male first or even repetitive sex changers. Natural selection should favour those individuals that change sex at a time when it increases their reproductive value. Allsop and West claim that the relative timing of sex change is invariant across all animals, with individuals changing sex at 72% of their maximum body size, and infer that natural selection for sex change must therefore be fundamentally similar across animals. Here we explain why we believe that Allsop and West's claims are not supported by their analysis or by their empirical data. PMID:15074315

  10. Effect of faecal soiling on skatole and androstenone occurrence in organic entire male pigs.

    PubMed

    Thomsen, R; Edwards, S A; Jensen, B B; Rousing, T; Srensen, J T

    2015-09-01

    Production of entire male pigs could be a future strategy for organic pig production. However, production of entire males leads to increased risk of carcasses with elevated boar taint levels. It is hypothesized that skatole levels in pig meat are affected by faecal soiling and that organic housing facilities can increase the risk of pigs being heavily soiled. Therefore, the overall aim of this study was to investigate if increased pig and pen soiling increases skatole concentration in entire male pigs. In five herds, 1174 organic entire male pigs were reared in four batches across two seasons, summer and winter. Measurements of pig and pen soiling, as well as fat skatole and androstenone concentration and human nose sensory tests of fat odour, were performed. Skatole and androstenone concentrations varied greatly within and between herds with a 10% and 90% percentile for the overall population of 0.02 and 2.25 g/g for skatole and 0.53 and 4.84 g/g for androstenone. Human nose positive tests averaged 18.3% with great variation between herds and seasons. Pen soiling had significant effects on pig soiling. Moreover, outdoor pen soiling significantly affected skatole concentration in interactions with herd and season (P<0.001 and P=0.003) and affected human nose positive risk in interaction with herd (P=0.005). Soiling on indoor pen areas did not affect skatole levels and no effect on androstenone was found for any pen area. Soiling of pigs affected both skatole and androstenone levels, with the size of the head and abdomen body areas covered in manure showing significant positive effects on skatole concentration. No effect of density of the manure layer was found on either boar taint measure. Herd significantly affected both skatole and androstenone in fat as well as the human nose positive risk. The human nose test revealed no effect from pig soiling. A large variation in the different boar taint measures was found for both high and low scores of pen and pig soiling, and only a small difference in skatole and androstenone concentrations between the high and low soiling categories was found. Therefore, while increasing the hygiene management could be a strategy for reducing boar taint in production of organic entire male pigs, it should be emphasized that other factors would also need to be considered. PMID:25990887

  11. Condition dependence of male and female reproductive success: insights from a simultaneous hermaphrodite.

    PubMed

    Janicke, Tim; Chapuis, Elodie

    2016-02-01

    Sexually selected traits are predicted to show condition dependence by capturing the genetic quality of its bearer. In separate-sexed organisms, this will ultimately translate into condition dependence of reproductive success of the sex that experiences sexual selection, which is typically the male. Such condition dependence of reproductive success is predicted to be higher in males than females under conditions promoting intense sexual selection. For simultaneous hermaphrodites, however, sex allocation theory predicts that individuals in poor condition channel relatively more resources into the male sex function at the expense of the female function. Thus, male reproductive success is expected to be less condition dependent than female reproductive success. We subjected individuals of the simultaneously hermaphroditic snail Physa acuta to two feeding treatments to test for condition dependence of male and female reproductive success under varying levels of male-male competition. Condition dependence was found for female, but not for male, reproductive success, meaning that selection on condition is relatively stronger through the female sex function. This effect was consistent over both male-male competition treatments. Decomposition of male and female reproductive performance revealed that individuals in poor condition copulated more in their male role, indicating an increased male allocation to mate acquisition. These findings suggest that sex-specific condition dependence of reproductive success is at least partially driven by condition-dependent sex allocation. We discuss the implications of condition-dependent sex allocation for the evolution of sexually selected traits in simultaneous hermaphrodites. PMID:26865970

  12. Bisphenol A alters autonomic tone and extracellular matrix structure and induces sex-specific effects on cardiovascular function in male and female CD-1 mice.

    PubMed

    Belcher, Scott M; Gear, Robin B; Kendig, Eric L

    2015-03-01

    The aim of this study was to determine whether bisphenol A (BPA) has adverse effects on cardiovascular functions in CD-1 mice and define sex-specific modes of BPA action in the heart. Dams and analyzed progeny were maintained on a defined diet containing BPA (0.03, 0.3, 3, 30, or 300 ppm) that resulted in BPA exposures from 4-5 to approximately 5000 μg/kg · d or a diet containing 17α-ethinyl estradiol (EE; ∼0.02, 0.2, and 0.15 μg/kg · d) as an oral bioavailable estrogen control. Assessment of electrocardiogram parameters using noninvasive methods found that ventricular functions in both male and female mice were not altered by either BPA or EE. However, exposure-related changes in the rates of ventricular contraction, suggestive of a shift in sympathovagal balance of heart rate control toward increased parasympathetic activity, were detected in males. Decreased systolic blood pressure was observed in males exposed to BPA above 5 μg/kg · d and in females from the highest BPA exposure group. Morphometric histological measures revealed sexually dimorphic changes in the composition of the cardiac collagen extracellular matrix, increases in fibrosis, and evidence of modest exposure-related remodeling. Experiments using the α-selective adrenergic agonist phenylephrine found that BPA enhanced reflex bradycardia in females, but not males, revealed that BPA and EE exposure sex specifically altered the sympathetic regulation of the baroreflex circuits. Increased sensitivity to the cardiotoxic effects of the β-adrenergic agonist isoproterenol was observed in BPA- and EE-exposed females. This effect was not observed in males, in which BPA or EE exposures were protective of isoproterenol-induced ischemic damage and hypertrophy. The results of RNA sequence analysis identified significant sex-specific changes in gene expression in response to BPA that were consistent with the observed exposure-related phenotypic changes in the collagenous and noncollagenous extracellular matrix, cardiac remodeling, altered autonomic responses, changes in ion channel and transporter functions, and altered glycolytic and lipid metabolism. PMID:25594700

  13. Bisphenol A Alters Autonomic Tone and Extracellular Matrix Structure and Induces Sex-Specific Effects on Cardiovascular Function in Male and Female CD-1 Mice

    PubMed Central

    Gear, Robin B.; Kendig, Eric L.

    2015-01-01

    The aim of this study was to determine whether bisphenol A (BPA) has adverse effects on cardiovascular functions in CD-1 mice and define sex-specific modes of BPA action in the heart. Dams and analyzed progeny were maintained on a defined diet containing BPA (0.03, 0.3, 3, 30, or 300 ppm) that resulted in BPA exposures from 4–5 to approximately 5000 μg/kg · d or a diet containing 17α-ethinyl estradiol (EE; ∼0.02, 0.2, and 0.15 μg/kg · d) as an oral bioavailable estrogen control. Assessment of electrocardiogram parameters using noninvasive methods found that ventricular functions in both male and female mice were not altered by either BPA or EE. However, exposure-related changes in the rates of ventricular contraction, suggestive of a shift in sympathovagal balance of heart rate control toward increased parasympathetic activity, were detected in males. Decreased systolic blood pressure was observed in males exposed to BPA above 5 μg/kg · d and in females from the highest BPA exposure group. Morphometric histological measures revealed sexually dimorphic changes in the composition of the cardiac collagen extracellular matrix, increases in fibrosis, and evidence of modest exposure-related remodeling. Experiments using the α-selective adrenergic agonist phenylephrine found that BPA enhanced reflex bradycardia in females, but not males, revealed that BPA and EE exposure sex specifically altered the sympathetic regulation of the baroreflex circuits. Increased sensitivity to the cardiotoxic effects of the β-adrenergic agonist isoproterenol was observed in BPA- and EE-exposed females. This effect was not observed in males, in which BPA or EE exposures were protective of isoproterenol-induced ischemic damage and hypertrophy. The results of RNA sequence analysis identified significant sex-specific changes in gene expression in response to BPA that were consistent with the observed exposure-related phenotypic changes in the collagenous and noncollagenous extracellular matrix, cardiac remodeling, altered autonomic responses, changes in ion channel and transporter functions, and altered glycolytic and lipid metabolism. PMID:25594700

  14. Male sex, height, weight, and body mass index can increase external pressure to calf region using knee-crutch-type leg holder system in lithotomy position

    PubMed Central

    Mizuno, Ju; Takahashi, Toru

    2016-01-01

    Background Well-leg compartment syndrome (WLCS) is one of the catastrophic complications related to prolonged surgical procedures performed in the lithotomy position, using a knee-crutch-type leg holder (KCLH) system, to support the popliteal fossae and calf regions. Obesity has been implicated as a risk factor in the lithotomy position-related WLCS during surgery. In the present study, we investigated the relationship between the external pressure (EP) applied to the calf region using a KCLH system in the lithotomy position and selected physical characteristics. Methods Twenty-one young, healthy volunteers (21.4±0.5 years of age, eleven males and ten females) participated in this study. The KCLH system used was Knee Crutch®. We assessed four types of EPs applied to the calf region: box pressure, peak box pressure, contact pressure, and peak contact pressure, using pressure-distribution measurement system (BIG-MAT®). Relationships between these four EPs to the calf regions of both lower legs and a series of physical characteristics (sex, height, weight, and body mass index [BMI]) were analyzed. Results All four EPs applied to the bilateral calf regions were higher in males than in females. For all subjects, significant positive correlations were observed between all four EPs and height, weight, and BMI. Conclusion EP applied to the calf region is higher in males than in females when the subject is supported by a KCLH system in the lithotomy position. In addition, EP increases with the increase in height, weight, and BMI. Therefore, male sex, height, weight, and BMI may contribute to the risk of inducing WLCS. PMID:26955278

  15. The sex pheromones of mealy plum (Hyalopterus pruni) and leaf-curl plum (Brachycaudus helichrysi) aphids: identification and field trapping of male and gynoparous aphids in prune orchards.

    PubMed

    Symmes, Emily J; Dewhirst, Sarah Y; Birkett, Michael A; Campbell, Colin A M; Chamberlain, Keith; Pickett, John A; Zalom, Frank G

    2012-05-01

    Mealy plum, Hyalopterus pruni, and leaf-curl plum, Brachycaudus helichrysi, aphids are the primary arthropod pests in orchards that produce dried plums (i.e., prunes). The sexual stage of their respective lifecycles occurs on prune trees in the fall, during which time males respond to sex pheromones produced by oviparous females. Air-entrainment collections confirmed that oviparous H. pruni and B. helichrysi emitted combinations of (4aS, 7S, 7aR)-nepetalactone and (1R, 4aS, 7S, 7aR)-nepetalactol. The responses of H. pruni and B. helichrysi to these compounds in ratios of 1:0, 0:1, 1:1, 2.6:1, 3.4:1, 5:1, 7:1, and 0:0 (no-pheromone control) using water traps were determined in field experiments conducted in prune orchards during the fall. The greatest number of male H. pruni was caught in traps releasing a 1:1 ratio of (4aS, 7S, 7aR)-nepetalactone and (1R, 4aS, 7S, 7aR)-nepetalactol, while male B. helichrysi were caught in similar numbers in traps releasing any of the two-component ratios tested. There was no evidence that any of the pheromone treatments influenced trap catches of gynoparae of either species. Results suggest that addition of sex pheromone lures increases trap catches of male H. pruni and B. helichrysi, and that this approach may improve monitoring and management of these pests in prune orchards. Knowledge gained from this study contributes to the understanding of the ecology of insect pests in prune orchards. PMID:22549554

  16. Drosophila male-specific lethal 2 protein controls sex-specific expression of the roX genes.

    PubMed Central

    Rattner, Barbara P; Meller, Victoria H

    2004-01-01

    The MSL complex of Drosophila upregulates transcription of the male X chromosome, equalizing male and female X-linked gene expression. Five male-specific lethal proteins and at least one of the two noncoding roX RNAs are essential for this process. The roX RNAs are required for the localization of MSL complexes to the X chromosome. Although the mechanisms directing targeting remain speculative, the ratio of MSL protein to roX RNA influences localization of the complex. We examine the transcriptional regulation of the roX genes and show that MSL2 controls male-specific roX expression in the absence of any other MSL protein. We propose that this mechanism maintains a stable MSL/roX ratio that is favorable for localization of the complex to the X chromosome. PMID:15126401

  17. The male sex pheromone darcin stimulates hippocampal neurogenesis and cell proliferation in the subventricular zone in female mice.

    PubMed

    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. 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

  19. Aphrodisiac Use Associated with HIV Infection in Elderly Male Clients of Low-Cost Commercial Sex Venues in Guangxi, China: A Matched Case-Control Study

    PubMed Central

    Li, Guojian; Shen, Zhiyong; Zhang, Hongman; Lan, Guanghua; Feng, Xue; Lin, Rui; Abdullah, Abu S.; Wu, Zunyou; Shi, Cynthia X.

    2014-01-01

    Background Rising HIV infection rates have been observed among elderly people in Guangxi, China. Inexpensive aphrodisiacs are available for purchase in suburban and rural areas. This study aims to investigate the association between aphrodisiac use and increased HIV risk for middle-aged and elderly men in Guangxi. Methods A matched case-control study of aphrodisiac use-associated HIV infection was performed among male subjects over 50 years old who were clients of low-cost commercial sex venues in Guangxi. The cases were defined as clients who were HIV-positive and two controls were selected for each case. The cases and the controls were matched on the visited sex venue, age (3 years), number of years of purchasing sex (3 years), and educational attainment. Subjects were interviewed and tested for HIV. Paired t-test or McNemar Chi-squared test were used to compare the characteristics between the cases and controls. A stepwise conditional logistic regression was used to identify risk factors associated with HIV infection. Findings This study enrolled 103 cases and 206 controls. Aphrodisiac use (P?=?0.02, odds ratio (OR)?=?1.81, 95% CI?=?1.083.04), never using condom during commercial sex encounter (P?=?0.03, odds ratio (OR)?=?1.82, 95% CI?=?1.083.07), and lacking a stable partner (P?=?0.03, odds ratio (OR)?=?1.76, 95% CI?=?1.052.98) were found to be risk factors for HIV infection among the study groups. For subjects reporting aphrodisiac use, the frequency of purchasing sex was positively correlated with the frequency of aphrodisiac use (r?=?0.3; p?=?0.02). Conclusions Aphrodisiac use was significantly associated with increased HIV infection risk in men over 50 years old who purchased commercial sex in the suburban and rural areas of Guangxi. Further research and interventions should address the links between aphrodisiac use, commercial sex work, condom use, and increased HIV transmission. PMID:25286369

  20. Expression of three gonadotropin subunits and gonadotropin receptor mRNA during male-to-female sex change in the cinnamon clownfish, Amphiprion melanopus.

    PubMed

    An, Kwang Wook; Lee, Jehee; Choi, Cheol Young

    2010-08-01

    To quantify the sex-change progression from male to female in the cinnamon clownfish, Amphiprion melanopus, we divided gonadal development into three stages (I, mature male; II, male at 90 days after removal of the female; and III, mature female), and the expression of GTH subunits and GTH receptors during each of these stages was investigated. The mRNA of the three GTH subunits and their receptors increased with progression from male to female. To understand the effect of gonadotropin-releasing hormone (GnRH) on this progression, we examined expression of genes encoding the GTH subunit mRNA in the pituitary and the GTH-receptor mRNA in the gonads in addition to investigating changes in plasma E(2) levels after GnRH analogue (GnRHa) injection. GnRHa treatment increased mRNA expression levels of these genes, as well as plasma E(2) levels, indicating that GnRH plays an important regulatory role in the brain-pituitary-gonad axis of immature cinnamon clownfish. PMID:20348005

  1. Seasonal changes in the testes and accessory reproductive organs and seasonal and circadian changes in plasma testosterone concentrations in the male grey squirrel (Sciurus carolinensis).

    PubMed

    Webley, G E; Pope, G S; Johnson, E

    1985-07-01

    A 27-month study of cycles of regression and recrudescence of testis function in adult, grey squirrels in a natural environment in southern England has shown concomitant variation in mean testes weights, mean plasma testosterone concentrations, and mean weights of accessory sex organs, this variation being closely associated with months of the year. Testis regression occurred in the period June to August, the exact timing differing among individuals. In 1979-1980 the testes of all squirrels then remained regressed for 7 months, whereas in the autumn of 1980 testes were regressed in most squirrels for 4 months. There was also evidence of testis regression in some individuals in March 1979 and March 1981. Males born and housed in a small woodland enclosure in 1979-1980 and well fed with grain did not experience the long period of regressed testes. Plasma testosterone concentrations measured hourly over 24 hr in squirrels with large, active testes varied from 0.4 to 20 nmol/l, both within and between individuals, the higher concentrations being observed between midday and midnight. The range in the age of males at puberty, based on fusion of the epiphyses of the wrist, was 1.0 to 1.25 year. Juvenile males housed in a woodland enclosure together with adult males and females remained prepubertal up to 2 years of age. PMID:4018551

  2. Clarifying relationships between persistent organic pollutant concentrations and age in wildlife biomonitoring: individuals, cross-sections, and the roles of lifespan and sex.

    PubMed

    Binnington, Matthew J; Wania, Frank

    2014-06-01

    Relationships between persistent organic pollutant (POP) levels and age in wildlife biomonitoring are often interpreted as changes in contaminant burden as organisms age. However, cross-sectional body burden-age trends (CBATs) obtained from biomonitoring studies, which sample individuals of different ages at the same time, should not be confused with longitudinal body burden-age trends (LBATs) obtained by sampling the same individuals repeatedly through time. To clarify how CBATs and LBATs for wildlife species deviate from each other, and describe any impact of lifespan and sex, we used mechanistic bioaccumulation models to estimate historic longitudinal exposures of polar cod, ringed seals, beluga whales, and bowhead whales to polychlorinated biphenyl congener 153. Cross-sectional body burden-age trends were then produced by sampling resultant LBATs of successive birth cohorts at specific time points. As found previously for humans, the year of sampling relative to the year of peak environmental contamination was a critical parameter in determining male CBAT shapes. However, a similar cohort effect was not apparent for reproductive females because efficient POP loss through lactation prevented their lipids from retaining a memory of past exposure levels. Thus, lactation loss was not only responsible for the large differences between the CBATs of males and females of the same species, but also the lack of female CBAT variability through time. Cross-sectional body burden-age trend shapes varied little between species by lifespan, as long as equivalent age scales were used. However, lifespan relative to the timescale of environmental contaminant level changes did determine the extent to which CBATs resembled LBATs for males. We suggest that accounting for birth cohort and sex effects is essential when interpreting age trends in POP biomonitoring studies of long-lived species. PMID:24619475

  3. A sex difference in the predisposition for physical competition: males play sports much more than females even in the contemporary U.S.

    PubMed

    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

  4. 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

  5. The olfactory system, not the terminal nerve, functions as the primary chemosensory pathway mediating responses to sex pheromones in male goldfish.

    PubMed

    Fujita, I; Sorensen, P W; Stacey, N E; Hara, T J

    1991-01-01

    Studies of the neural mechanisms underlying responsiveness to sex pheromones in male goldfish suggest that, contrary to a currently popular hypothesis, the olfactory system (cranial nerve 1), and not the terminal nerve (cranial nerve 0), mediates chemosensory responses to pheromones. When the olfactory epithelium of male goldfish was exposed to two identified sex pheromones, 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one and a mixture of prostaglandin F2 alpha and its metabolite 15-keto-prostaglandin F2 alpha, the spontaneous activity of olfactory neurons located in the medical portion of the olfactory bulb changed, while activity of terminal nerve cell bodies did not. A variety of other synthetic and natural odors also failed to alter the activity of terminal nerve cell bodies as did visual, magnetic, thermal, and auditory cues. Terminal nerve activity was, however, inhibited by tactile stimulation, suggesting that this system may have a modulatory role associated with the physical interactions that characterize goldfish spawning behavior. PMID:1662555

  6. 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

  7. 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.; Fechner, P.Y.

    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.

  8. Role of the pseudoautosomal region in sex-chromosome pairing during male meiosis: Meiotic studies in a man with a deletion of distal Xp

    SciTech Connect

    Mohandas, T.K.; Passage, M.B.; Yen, P.H.; Speed, R.M.; Chandley, A.C.; Shapiro, L.J. )

    1992-09-01

    Meiotic studies were undertaken in a 24-year-old male patient with short stature, chondrodysplasia punctata, ichthyosis, steroid sulfatase deficiency, and mild mental retardation with an inherited cytologically visible deletion of distal Xp. Molecular investigations showed that the pseudoautosomal region as well as the steroid sulfatase gene were deleted, but telomeric sequences were present at the pter on the deleted X chromosome. A complete failure of sex-chromosome pairing was observed in the primary spermatocytes of the patient. Telomeric approaches between the sex chromosomes were made at zygotene in some cells, but XY synaptonemal complex was formed. The sex chromosomes were present as univalents at metaphase I, and germ-cell development was arrested between metaphase I and metaphase II in the vast majority of cells, consistent with the azoospermia observed in the patient. The failure of XY pairing in this individual indicates that the pseudoautosomal sequences play an important role in initiating XY pairing and formation of synaptonemal complex at meiosis. 36 refs., 6 figs.

  9. AGO4 regulates entry into meiosis and influences silencing of sex chromosomes in the male mouse germ line

    PubMed Central

    Modzelewski, Andrew J.; Holmes, Rebecca J.; Hilz, Stephanie; Grimson, Andrew; Cohen, Paula E.

    2012-01-01

    Summary The four mammalian Argonaute family members are thought to share redundant functions in the microRNA pathway, yet only AGO2 possesses the catalytic “slicer” function required for RNA interference. Whether AGO1, AGO3, or AGO4 possess specialized functions remains unclear. Here we show that AGO4 localizes to spermatocyte nuclei during meiotic prophase I, specifically at sites of asynapsis and the transcriptionally silenced XY sub-domain, the sex body. We generated Ago4 knockout mice and show that Ago4−/− spermatogonia initiate meiosis early, resulting from premature induction of retinoic acid-response genes. During prophase I, the sex body assembles incorrectly in Ago4−/− mice, leading to disrupted meiotic sex chromosome inactivation (MSCI). This is associated with a dramatic loss of microRNAs, >20% of which arise from the X chromosome. Thus, AGO4 regulates meiotic entry and MSCI in mammalian germ cells, implicating small RNA pathways in these processes. PMID:22863743

  10. Sex differences in the brain: a whole body perspective.

    PubMed

    de Vries, Geert J; Forger, Nancy G

    2015-01-01

    Most writing on sexual differentiation of the mammalian brain (including our own) considers just two organs: the gonads and the brain. This perspective, which leaves out all other body parts, misleads us in several ways. First, there is accumulating evidence that all organs are sexually differentiated, and that sex differences in peripheral organs affect the brain. We demonstrate this by reviewing examples involving sex differences in muscles, adipose tissue, the liver, immune system, gut, kidneys, bladder, and placenta that affect the nervous system and behavior. The second consequence of ignoring other organs when considering neural sex differences is that we are likely to miss the fact that some brain sex differences develop to compensate for differences in the internal environment (i.e., because male and female brains operate in different bodies, sex differences are required to make output/function more similar in the two sexes). We also consider evidence that sex differences in sensory systems cause male and female brains to perceive different information about the world; the two sexes are also perceived by the world differently and therefore exposed to differences in experience via treatment by others. Although the topic of sex differences in the brain is often seen as much more emotionally charged than studies of sex differences in other organs, the dichotomy is largely false. By putting the brain firmly back in the body, sex differences in the brain are predictable and can be more completely understood. PMID:26279833

  11. Anopheles arabiensis egg treatment with dieldrin for sex separation leaves residues in male adult mosquitoes that can bioaccumulate in goldfish (Carassius auratus auratus)

    PubMed Central

    Yamada, Hanano; Jandric, Zora; Chhem-Kieth, Sorivan; Vreysen, Marc JB; Rathor, Mohammad N; Gilles, Jeremie RL; Cannavan, Andrew

    2013-01-01

    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

  12. Sex Stereotypic Behavior in Infants: An Analysis of Social-Interpersonal Relationships.

    ERIC Educational Resources Information Center

    Lewis, Michael

    This paper discusses the processes that are at work which produce some of the differences between male and female human beings. The sex of the child is an important attribute of the organism's identity. Before birth, parents express preferences for the sex of the unborn child and start providing names as a function of the sex of the child. Studies

  13. Sex Isn't that Simple: Culture and Context in HIV Prevention Interventions for Gay and Bisexual Male Adolescents

    ERIC Educational Resources Information Center

    Harper, Gary W.

    2007-01-01

    Gay and bisexual male adolescents and young adults in the United States have been disproportionately impacted by the HIV pandemic. Despite the steadily increasing rise in their HIV infection rates, there has not been a commensurate increase in HIV prevention programs targeted to the unique social and sexual lives of these youths. Programs that

  14. 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…

  15. Male-produced sex pheromone of the carrion beetles, Oxelytrum discicolle and its attraction to food sources.

    PubMed

    Fockink, Douglas H; Mise, Kleber M; Zarbin, Paulo H G

    2013-08-01

    Carrion beetles are part of the great diversity of insects collected on cadavers. In Brazil, beetles of the genus Oxelytrum have great forensic importance in post mortem interval (PMI) estimation. We investigated the system of chemical communication in the attraction of these necrophagous beetles. Gas chromatographic analysis (GC) of female and male aeration extracts revealed the presence of two male-specific compounds, produced in a ratio of 94:6. Bioassays showed that the combination of male produced volatiles and the odor of a food source (carcass volatiles) were attractive to females. Mass and infrared spectral analyses of the male-specific compounds suggested that they were both unsaturated hydrocarbons. Several micro-derivatizations were carried out with the natural products, and the target structures were identified as (Z)-1,8-heptadecadiene (major) and 1-heptadecene (minor). The structure of the minor component was assigned by co-injection with a commercial standard. A seven-step synthesis was developed to synthesize (Z)-1,8-heptadiene, which co-eluted with the major natural product on three different GC stationary phases. Y-tube olfactometer assays showed that the mixture of synthetic standards in the naturally occurring proportion was slightly attractive to females. The results contribute both to the understanding of the chemical ecology of O. discicolle and to its potential to improve the accuracy of PMI estimation. PMID:23918548

  16. Sex Isn't that Simple: Culture and Context in HIV Prevention Interventions for Gay and Bisexual Male Adolescents

    ERIC Educational Resources Information Center

    Harper, Gary W.

    2007-01-01

    Gay and bisexual male adolescents and young adults in the United States have been disproportionately impacted by the HIV pandemic. Despite the steadily increasing rise in their HIV infection rates, there has not been a commensurate increase in HIV prevention programs targeted to the unique social and sexual lives of these youths. Programs that…

  17. FANCB is essential in the male germline and regulates H3K9 methylation on the sex chromosomes during meiosis.

    PubMed

    Kato, Yasuko; Alavattam, Kris G; Sin, Ho-Su; Meetei, Amom Ruhikanta; Pang, Qishen; Andreassen, Paul R; Namekawa, Satoshi H

    2015-09-15

    Fanconi anemia (FA) is a recessive X-linked and autosomal genetic disease associated with bone marrow failure and increased cancer, as well as severe germline defects such as hypogonadism and germ cell depletion. Although deficiencies in FA factors are commonly associated with germ cell defects, it remains unknown whether the FA pathway is involved in unique epigenetic events in germ cells. In this study, we generated Fancb mutant mice, the first mouse model of X-linked FA, and identified a novel function of the FA pathway in epigenetic regulation during mammalian gametogenesis. Fancb mutant mice were infertile and exhibited primordial germ cell (PGC) defects during embryogenesis. Further, Fancb mutation resulted in the reduction of undifferentiated spermatogonia in spermatogenesis, suggesting that FANCB regulates the maintenance of undifferentiated spermatogonia. Additionally, based on functional studies, we dissected the pathway in which FANCB functions during meiosis. The localization of FANCB on sex chromosomes is dependent on MDC1, a binding partner of H2AX phosphorylated at serine 139 (?H2AX), which initiates chromosome-wide silencing. Also, FANCB is required for FANCD2 localization during meiosis, suggesting that the role of FANCB in the activation of the FA pathway is common to both meiosis and somatic DNA damage responses. H3K9me2, a silent epigenetic mark, was decreased on sex chromosomes, whereas H3K9me3 was increased on sex chromosomes in Fancb mutant spermatocytes. Taken together, these results indicate that FANCB functions at critical stages of germ cell development and reveal a novel function of the FA pathway in the regulation of H3K9 methylation in the germline. PMID:26123487

  18. Male sexuality and Alfred Kinsey's 0-6 scale: toward "a sound understanding of the realities of sex".

    PubMed

    Drucker, Donna J

    2010-01-01

    Using a 0-6 scale, Alfred Kinsey demonstrated that the complexity of human sexuality could best be represented on a continuum rather than as a binary. Kinsey developed the scale from models created by his predecessors in human sex research. A primary intention of the scale was to eradicate sexual identity categories altogether in order to eliminate sexual identity-based persecutions and to promote equal rights. As proponents and opponents of homosexual rights both depended on constructions of sexual identity to advance their agendas, Kinsey's ideal was never realized. The scale nonetheless continues to challenge postmodern associations of identity and sexuality. PMID:20924926

  19. Surface models of the male urogenital organs built from the Visible Korean using popular software

    PubMed Central

    Shin, Dong Sun; Park, Jin Seo; Shin, Byeong-Seok

    2011-01-01

    Unlike volume models, surface models, which are empty three-dimensional images, have a small file size, so they can be displayed, rotated, and modified in real time. Thus, surface models of male urogenital organs can be effectively applied to an interactive computer simulation and contribute to the clinical practice of urologists. To create high-quality surface models, the urogenital organs and other neighboring structures were outlined in 464 sectioned images of the Visible Korean male using Adobe Photoshop; the outlines were interpolated on Discreet Combustion; then an almost automatic volume reconstruction followed by surface reconstruction was performed on 3D-DOCTOR. The surface models were refined and assembled in their proper positions on Maya, and a surface model was coated with actual surface texture acquired from the volume model of the structure on specially programmed software. In total, 95 surface models were prepared, particularly complete models of the urinary and genital tracts. These surface models will be distributed to encourage other investigators to develop various kinds of medical training simulations. Increasingly automated surface reconstruction technology using commercial software will enable other researchers to produce their own surface models more effectively. PMID:21829759

  20. Surface models of the male urogenital organs built from the Visible Korean using popular software.

    PubMed

    Shin, Dong Sun; Park, Jin Seo; Shin, Byeong-Seok; Chung, Min Suk

    2011-06-01

    Unlike volume models, surface models, which are empty three-dimensional images, have a small file size, so they can be displayed, rotated, and modified in real time. Thus, surface models of male urogenital organs can be effectively applied to an interactive computer simulation and contribute to the clinical practice of urologists. To create high-quality surface models, the urogenital organs and other neighboring structures were outlined in 464 sectioned images of the Visible Korean male using Adobe Photoshop; the outlines were interpolated on Discreet Combustion; then an almost automatic volume reconstruction followed by surface reconstruction was performed on 3D-DOCTOR. The surface models were refined and assembled in their proper positions on Maya, and a surface model was coated with actual surface texture acquired from the volume model of the structure on specially programmed software. In total, 95 surface models were prepared, particularly complete models of the urinary and genital tracts. These surface models will be distributed to encourage other investigators to develop various kinds of medical training simulations. Increasingly automated surface reconstruction technology using commercial software will enable other researchers to produce their own surface models more effectively. PMID:21829759

  1. Whole adult organism transcriptional profiling of acute metal exposures in male Zebrafish

    PubMed Central

    2014-01-01

    Background A convergence of technological breakthroughs in the past decade has facilitated the development of rapid screening tools for biomarkers of toxicant exposure and effect. Platforms using the whole adult organism to evaluate the genome-wide response to toxicants are especially attractive. Recent work demonstrates the feasibility of this approach in vertebrates using the experimentally robust zebrafish model. In the present study, we evaluated gene expression changes in whole adult male zebrafish following an acute 24 hr high dose exposure to three metals with known human health risks. Male adult zebrafish were exposed to nickel chloride, cobalt chloride or sodium dichromate concentrations corresponding to their respective 96 hr LC20, LC40 and LC60. Histopathology was performed on a subset of metal-exposed zebrafish to phenotypically anchor transcriptional changes associated with each metal. Results Comparative analysis identified subsets of differentially expressed transcripts both overlapping and unique to each metal. Application of gene ontology (GO) and transcription factor (TF) enrichment algorithms revealed a number of key biological processes perturbed by metal poisonings and the master transcriptional regulators mediating gene expression changes. Metal poisoning differentially activated biological processes associated with ribosome biogenesis, proteosomal degradation, and p53 signaling cascades, while repressing oxygen-generating pathways associated with amino acid and lipid metabolism. Despite appreciable effects on gene regulation, nickel poisoning did not induce any morphological alterations in male zebrafish organs and tissues. Histopathological effects of cobalt remained confined to the olfactory system, while chromium targeted the gills, pharynx, and intestinal mucosa. A number of enriched transcription factors mediated the observed gene response to metal poisoning, including known targets such as p53, HIF1α, and the myc oncogene, and novel regulatory factors such as XBP1, GATA6 and HNF3β. Conclusions This work uses an experimentally innovative approach to capture global responses to metal poisoning and provides mechanistic insights into metal toxicity. PMID:24612858

  2. Age- and sex-related differences of organic anion-transporting polypeptide gene expression in livers of rats

    SciTech Connect

    Hou, Wei-Yu; Xu, Shang-Fu; Zhu, Qiong-Ni; Lu, Yuan-Fu; Cheng, Xing-Guo; Liu, Jie

    2014-10-15

    Organic anion-transporting polypeptides (Oatps) play important roles in transporting endogenous substances and xenobiotics into the liver and are implicated in drug-drug interactions. Many factors could influence their expression and result in alterations in drug disposition, efficacy and toxicity. This study was aimed to examine the development-, aging-, and sex-dependent Oatps expression in livers of rats. The livers from SD rats during development (− 2, 1, 7, 14, 21, 28, 35, and 60 d) and aging (60, 180, 540 and/or 800 d) were collected and total RNAs were extracted, purified, and subjected to real-time PCR analysis. Total proteins were extracted for western-blot analysis. Results showed that Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 were all hardly detectable in fetal rat livers, low at birth, rapidly increased after weaning (21 d), and reached the peak at 60 d. The Oatps remained stable during the age between 60–180 d, and decreased at elderly (540 and/or 800 d). After birth, Oatp1a1, Oatp1a4, and Oatp1b2 were all highly expressed in liver, in contrast, Oatp1a5 expression was low. Oatp expressions are male-predominant in rat livers. In the livers of aged rats, the Oatp expression decreased and shared a consistent ontogeny pattern at the mRNA and protein level. In conclusion, this study showed that in rat liver, Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 gene expressions are influenced by age and gender, which could provide a basis of individual variation in drug transport, metabolism and toxicity in children, elderly and women. - Highlights: • Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 expression in livers of rats. • Ontogenic changes of Oatps at − 2, 1, 7, 14, 21, 28, 35, and 60 days. • Age-related changes of Oatps at 60, 180, 540, and 800 days. • Sex-difference of Oatps at the both mRNA and protein levels.

  3. Effects of age, sex, and persistent organic pollutants on DNA methylation in children

    PubMed Central

    Huen, Karen; Yousefi, Paul; Bradman, Asa; Yan, Liying; Harley, Kim G.; Kogut, Katherine; Eskenazi, Brenda; Holland, Nina

    2015-01-01

    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 9-year old children (n=358). POPs were measured in maternal serum during late pregnancy. Levels of DNA methylation were lower in 9-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

  4. 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

  5. Sex allocation predicts mating rate in a simultaneous hermaphrodite

    PubMed Central

    Janicke, Tim; Schrer, Lukas

    2009-01-01

    Sexual selection theory for separate-sexed animals predicts that the sexes differ in the benefit they can obtain from multiple mating. Conventional sex roles assume that the relationship between the number of mates and the fitness of an individual is steeper in males compared with females. Under these conditions, males are expected to be more eager to mate, whereas females are expected to be choosier. Here we hypothesize that the sex allocation, i.e. the reproductive investment devoted to the male versus female function, can be an important predictor of the mating strategy in simultaneous hermaphrodites. We argue that within-species variation in sex allocation can cause differences in the proportional fitness gain derived through each sex function. Individuals should therefore adjust their mating strategy in a way that is more beneficial to the sex function that is relatively more pronounced. To test this, we experimentally manipulated the sex allocation in a simultaneously hermaphroditic flatworm and investigated whether this affects the mating behaviour. The results demonstrate that individuals with a more male-biased sex allocation (i.e. relatively large testes and small ovaries) are more eager to mate compared with individuals with a more female-biased sex allocation (i.e. relatively small testes and large ovaries). We argue that this pattern is comparable to conventional gender roles in separate-sexed organisms. PMID:19740883

  6. Use of a deslorelin implant for influencing sex hormones and male behaviour in a stallion - Case report.

    PubMed

    Schnert, Susanne; Reher, Martina; Gruber, Achim D; Carstanjen, Bianca

    2012-12-01

    This case report describes the use of a subcutaneously applied 4.7-mg deslorelin acetate implant in a three-year-old Arabian crossbred stallion showing unwanted strong male behaviour. Following deslorelin acetate implantation the stallion showed a short transitional increase in male behaviour. A 'gelding-like' behaviour was noted 15 days (D15) after treatment. The horse was surgically castrated at the owners request at D52 after treatment. Serum testosterone, oestradiol-17? and oestrone sulphate values decreased after deslorelin acetate implantation, but serum LH and FSH levels remained unchanged. Histopathological analysis of both testes and sperm analysis revealed a reduced spermatogenesis at D52. The testicular volume decreased after treatment. The use of a subcutaneously applied deslorelin acetate implant might be a promising tool to change the behaviour of aggressive stallions. PMID:23160033

  7. 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

    2016-03-01

    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

  8. The protein synthesis inhibitor anisomycin reduces sex behavior during a critical period after testosterone treatment in male Syrian hamsters.

    PubMed

    Piekarski, David J; Seto, Tiffany; Zucker, Irving

    2012-01-18

    Testosterone (T) is critical for maintaining male sexual behavior (MSB) in rodents, in part by altering protein synthesis in a well-defined neural circuit. The specific timing of protein synthesis essential for expression of MSB has never been investigated. We administered the protein synthesis inhibitor anisomycin (Ani) to castrated male Syrian hamsters treated sc with 100 μg T in an aqueous vehicle once weekly; this T regimen maintains MSB while elevating circulating T concentrations for only a few hours after each injection. Hamsters were injected s.c. with the vehicle or 12.5 mg Ani at one of several times relative to T administration; MSB was assessed once per week, 6 days after the previous T injection, for 5 weeks. Anisomycin administered 6-12 h after T injection significantly reduced the expression of sexual behavior, whereas Ani treatment between 3 h before and 3 h after T injection did not impair MSB. This experiment is the first to assess the specific timing of protein synthesis relative to a T pulse that is required for the expression of MSB. The demarcation of a critical interval for T-induced protein synthesis necessary for maintenance of MSB should facilitate specification of the genomic, proteomic, and biochemical cascades that subserve actions of T on male copulation. PMID:21896280

  9. Specificity of female and male sex hormones on excitatory and inhibitory phases of formalin-induced nociceptive responses.

    PubMed

    Gaumond, Isabelle; Arsenault, Pierre; Marchand, Serge

    2005-08-01

    Several factors have been proposed to account for the differences observed between men and women in pain perception. One of these is female and male gonadal hormones. In order to verify this assumption, a hormone replacement (pellets inserted subcutaneously) of (1) 17beta-estradiol, (2) progesterone, (3) 17beta-estradiol + progesterone or (4) testosterone have been performed in gonadectomized female and male Sprague-Dawley rats. Twenty-one days after the hormonal replacement, a formalin test was performed. The nociceptive responses were divided in three distinct phases: acute (phase I), inhibitory (interphase) and tonic (phase II). After analysis, we observed that testosterone has a hypoalgesic effect on phases I and II of the formalin test. At the opposite, female hormones act only on the interphase: the combination of 17beta-estradiol and progesterone in gonadectomized rats reestablishes the weaker nociceptive pain reduction during the interphase as it is observed in the intact female. These effects were not gender specific since they had the same action in female and male. Our results permit to believe that testosterone plays a protective role in pain perception. Moreover, the female hormones act mainly on pain inhibition mechanisms (interphase), suggesting that the prevalence of certain chronic pain conditions in women could be related to a deficit of these pain inhibitory mechanisms rather than an increased nociceptive activity. PMID:16005855

  10. Cues to sex- and stress-hormones in the human male face: functions of glucocorticoids in the immunocompetence handicap hypothesis.

    PubMed

    Moore, F R; Al Dujaili, E A S; Cornwell, R E; Smith, M J Law; Lawson, J F; Sharp, M; Perrett, D I

    2011-08-01

    The stress-linked version of the immunocompetence handicap hypothesis has been proposed to account for inconsistencies in relationships between testosterone and immune response. The model has received some support from studies demonstrating roles of stress hormones in relationships between testosterone, immune function and secondary sexual ornamentation. Such work, however, has relied on artificial elevation of testosterone so may not reflect relationships in natural populations. We created human male facial stimuli on the basis of naturally co-occurring levels of salivary testosterone and the stress hormone cortisol. In Study 1 we tested female preferences for male faces with cues to combinations of the hormones across the menstrual cycle, and in Study 2 we tested perceptions of health and dominance in a novel set of facial stimuli. Females preferred cues to low cortisol, a preference that was strongest during the fertile phase of the menstrual cycle. The effects of cortisol on attractiveness and perceived health and dominance were contingent upon level of testosterone: the effects of the stress hormone were reduced when testosterone was high. We propose explanations for our results, including low cortisol as a cue to a heritable component of health, attractiveness as a predictor of low social-evaluative threat (and, therefore, low baseline cortisol) and testosterone as a proxy of male ability to cope efficiently with stressors. PMID:21672543

  11. 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. PMID:26064173

  12. 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

  13. [Modulating effects of androgens on development adaptive-compensatory processes in organism of experimental animals-males].

    PubMed

    Didebulidze, N A; Sumbadze, Ts M; Melikadze, E B; Gvidani, S A; Kakabadze, M Sh

    2010-09-01

    The purpose of research is the definition of androgens role and myocardial androgen receptors and sex steroids in males under metabolic and hormonal "stress" induced by the experimental diabetes. Research was carried out on 60 rats-males, mass 180,0-200,0 g. The diabetes reproduced by single injection of alloxan (200mg/kg). Androgen receptors were revealed by the radiometric and radioautography methods. The content of glucose, immunoreactive insulin, testosteron, estradiol, corticosteron and somatotropin were defined in animals blood plasma. On the early terms of alloxan diabetes estradiol concentration increase against a background of testosteron decrease which causes the "feminization" of the sexual hormonal balance. On the other side the increase of androgen receptors expression by cardiomyocytes causes the intensification of myocardium tissue physiologic ability to androgens perception positively influencing on the metabolism. Consequently, androgens provoke stimulating effect on the myocard metabolism in males at early stages of the experimental diabetes. PMID:20972279

  14. 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

  15. Sex differences in the vomeronasal system.

    PubMed

    Guillamón, A; Segovia, S

    1997-01-01

    In the early eighties we found sex differences in the vomeronasal organ (VNO) and hypothesized that the vomeronasal system (VNS), a complex neural network involved in the control of reproductive behavior, might be sexually dimorphic. At that time sex differences had already been described for some structures that receive VNO input, such as the medial amygdala, the medial preoptic area, the ventromedial hypothalamic nucleus, and the ventral region of the premammillary nucleus. Since then, we have shown sex differences in the accessory olfactory bulb (AOB), the bed nucleus of the accessory olfactory tract (BAOT), and the bed nucleus of the stria terminalis (BST). When new VNS connections were found, all of them ended in nuclei that present sex differences. In general, sex differences in the olfactory system show two morphological patterns: one in which males present greater morphological measures than females, and just the opposite. To explain the morphometric measures of males in the latter, it has been hypothesized that androgens serve as inhibitors. Our work on the involvement of the GABA(A) receptor in the development of AOB and maternal behavior sex differences also suggests that neonatal changes in neuronal membrane permeability to the ion Cl- differences. This might be the first animal model to help us to understand the situation in which human genetic and gonadal sex do not agree with brain and behavioral sex. Finally, we stress that sex differences in the VNS constitute a neurofunctional model for understanding sex differences in reproductive behaviors. PMID:9370202

  16. Chronic high-dose creatine has opposing effects on depression-related gene expression and behavior in intact and sex hormone-treated gonadectomized male and female rats

    PubMed Central

    Allen, Patricia J.; DeBold, Joseph F.; Rios, Maribel; Kanarek, Robin B.

    2015-01-01

    Creatine is an antioxidant, neuromodulator and key regulator of energy metabolism shown to improve depressive symptoms in humans and animals, especially in females. To better understand the pharmacological effects of creatine, we examined its influence on depression-related hippocampal gene expression and behaviors in the presence and absence of sex steroids. Sham-operated and gonadectomized male and female rats were fed chow alone or chow blended with either 2% or 4% w/w creatine monohydrate for five weeks before forced swim, open field, and wire suspension tests, or seven weeks total. Before supplementation, males were chronically implanted with an empty or a testosterone-filled (T) capsule (10-mm surface release), and females were administered progesterone (P, 250 μg), estradiol benzoate (EB, 2.5 μg), EB+P, or sesame oil vehicle weekly. Relative to non-supplemented shams, all hippocampal plasticity-related mRNAs measured, including brain-derived neurotrophic factor (BDNF), tyrosine kinase B, doublecortin, calretinin, and calbindin, were downregulated in sham males given 4% creatine, and BDNF, doublecortin, and calbindin mRNAs were downregulated in sham females given 4% creatine. In contrast, combined 4% creatine + T in castrates prevented downregulation of BDNF, doublecortin, and calretinin mRNAs. Similarly, combined 4% creatine + EB+P in ovariectomized females attenuated downregulation of BDNF and calbindin mRNA levels. Moderate antidepressant and anxiolytic-like behaviors were observed in EB+P-treated ovariectomized females fed creatine, with similar trends in T-treated castrates fed creatine. Altogether, these data show that chronic, high-dose creatine has opposing effects on neuroplasticity-related genes and depressive behavior in intact and gonadectomized male and female rats. The dose and schedule of creatine used negatively impacted hippocampal neuronal integrity in otherwise healthy brains, possibly through negative compensatory changes in energy metabolism, whereas combined creatine and sex steroids acted in a neuroprotective manner in gonadectomized rats, potentially by reducing metabolic complications associated with castration or ovariectomy. PMID:25560941

  17. Chronic high-dose creatine has opposing effects on depression-related gene expression and behavior in intact and sex hormone-treated gonadectomized male and female rats.

    PubMed

    Allen, Patricia J; DeBold, Joseph F; Rios, Maribel; Kanarek, Robin B

    2015-03-01

    Creatine is an antioxidant, neuromodulator and key regulator of energy metabolism shown to improve depressive symptoms in humans and animals, especially in females. To better understand the pharmacological effects of creatine, we examined its influence on depression-related hippocampal gene expression and behaviors in the presence and absence of sex steroids. Sham-operated and gonadectomized male and female rats were fed chow alone or chow blended with either 2% or 4% w/w creatine monohydrate for five weeks before forced swim, open field, and wire suspension tests, or seven weeks total. Before supplementation, males were chronically implanted with an empty or a testosterone-filled (T) capsule (10-mm surface release), and females were administered progesterone (P, 250 ?g), estradiol benzoate (EB, 2.5 ?g), EB+P, or sesame oil vehicle weekly. Relative to non-supplemented shams, all hippocampal plasticity-related mRNAs measured, including brain-derived neurotrophic factor (BDNF), tyrosine kinase B, doublecortin, calretinin, and calbindin, were downregulated in sham males given 4% creatine, and BDNF, doublecortin, and calbindin mRNAs were downregulated in sham females given 4% creatine. In contrast, combined 4% creatine+T in castrates prevented downregulation of BDNF, doublecortin, and calretinin mRNAs. Similarly, combined 4% creatine+EB+P in ovariectomized females attenuated downregulation of BDNF and calbindin mRNA levels. Moderate antidepressant and anxiolytic-like behaviors were observed in EB+P-treated ovariectomized females fed creatine, with similar trends in T-treated castrates fed creatine. Altogether, these data show that chronic, high-dose creatine has opposing effects on neuroplasticity-related genes and depressive behavior in intact and gonadectomized male and female rats. The dose and schedule of creatine used negatively impacted hippocampal neuronal integrity in otherwise healthy brains, possibly through negative compensatory changes in energy metabolism, whereas combined creatine and sex steroids acted in a neuroprotective manner in gonadectomized rats, potentially by reducing metabolic complications associated with castration or ovariectomy. PMID:25560941

  18. Isolation and characterization of sex chromosome rearrangements generating male muscle dystrophy and female abnormal oogenesis in the silkworm, Bombyx mori.

    PubMed

    Fujii, T; Yokoyama, T; Ninagi, O; Kakehashi, K; Obara, Y; Nenoi, M; Ishikawa, T; Mita, K; Shimada, T; Abe, H

    2007-07-01

    In deletion-mapping of W-specific RAPD (W-RAPD) markers and putative female determinant gene (Fem), we used X-ray irradiation to break the translocation-carrying W chromosome (W( Ze )). We succeeded in obtaining a fragment of the W( Ze ) chromosome designated as Ze (W), having 3 of 12 W-RAPD markers (W-Bonsai, W-Yukemuri-S, W-Yukemuri-L). Inheritance of the Ze (W) fragment by males indicates that it does not include the Fem gene. On the basis of these results, we determined the relative positions of W-Yukemuri-S and W-Yukemuri-L, and we narrowed down the region where Fem gene is located. In addition to the Ze (W) fragment, the Z chromosome was also broken into a large fragment (Z(1)) having the +( sch ) (1-21.5) and a small fragment (Z(2)) having the +( od ) (1-49.6). Moreover, a new chromosomal fragment (Ze (W)Z(2)) was generated by a fusion event between the Ze (W) and the Z(2) fragments. We analyzed the genetic behavior of the Z(1) fragment and the Ze (W)Z(2) fragment during male (Z/Z(1) Ze (W)Z(2)) and female (Z(1) Ze (W)Z(2)/W) meiosis using phenotypic markers. It was observed that the Z(1) fragment and the Z or the W chromosomes separate without fail. On the other hand, non-disjunction between the Ze (W)Z(2) fragment and the Z chromosome and also between the Ze (W)Z(2) fragment and the W chromosome occurred. Furthermore, the females (2A: Z/Ze (W)Z(2)/W) and males (2A: Z/Z(1)) resulting from non-disjunction between the Ze (W)Z(2) fragment and the W chromosome had phenotypic defects: namely, females exhibited abnormal oogenesis and males were flapless due to abnormal indirect flight muscle structure. These results suggest that Z(2) region of the Z chromosome contains dose-sensitive gene(s), which are involved in oogenesis and indirect flight muscle development. PMID:17031495

  19. STI/HIV test result disclosure between female sex workers and their primary, noncommercial male partners in two Mexico-U.S. border cities

    PubMed Central

    Pines, Heather A.; Patterson, Thomas L.; Rangel, Gudelia; Martinez, Gustavo; Robertson, Angela M.; Ulibarri, Monica D.; Syvertsen, Jennifer L.; Martin, Natasha K.; Strathdee, Steffanie A.

    2015-01-01

    Objectives Disclosure of STI/HIV results to sexual partners in Mexico is left to the individual as public health guidelines do not mandate disclosure. To assess the feasibility of couples-based STI/HIV testing with facilitated disclosure as a risk reduction strategy within female sex workers (FSWs) primary partnerships, we examined current STI/HIV test result disclosure patterns between FSWs and their primary, non-commercial male partners in Tijuana and Ciudad Jurez, two Mexico-U.S. border cities. Methods In a cohort study (20102013), 330 participants (178 FSWs and 152 primary male partners) were followed for 24 months. At semi-annual visits, participants were tested for STIs/HIV and reported on their disclosure of test results from the prior visit. Multilevel logistic regression for dyadic data was used to identify individual- and partnership-level predictors of cumulative STI/HIV test result disclosure within couples during follow-up (disclosed all results vs. did not disclose ?1 result). Results Eighty-seven percent of participants reported disclosing all STI/HIV test results to their primary partners. Non-disclosure of ?1 STI/HIV test result was more common among participants who reported an STI/HIV diagnosis as part of the study (adjusted odds ratio [AOR]=3.54, 95% confidence interval [CI]: 1.1810.60), those in longer-duration partnerships (AOR=1.11 per year, 95% CI: 1.011.21), and those who used drugs before/during sex within partnerships (AOR=3.71, 95% CI: 1.1611.86). Non-disclosure was less common among participants who injected drugs (AOR=0.27, 95% CI: 0.090.80). Conclusions STI/HIV test result disclosure was highly prevalent within FSWs primary partnerships, suggesting couples-based STI/HIV testing with facilitated disclosure may be feasible for these and potentially other socially-marginalized couples. PMID:25298381

  20. Health, trust, or "just understood": explicit and implicit condom decision-making processes among black, white, and interracial same-sex male couples.

    PubMed

    Campbell, Chadwick K; Gmez, Anu Manchikanti; Dworkin, Shari; Wilson, Patrick A; Grisham, Kirk K; McReynolds, Jaih; Vielehr, Peter; Hoff, Colleen

    2014-05-01

    Among gay and bisexual men, primary partners are a leading source of HIV infection. Trust, intimacy, and advancements in HIV treatment may impact same-sex male (SSM) couples' decisions to engage in unprotected anal intercourse (UAI). This qualitative study explored how Black, White and interracial couples discussed, and made decisions regarding condoms. Qualitative interviews were conducted with 48 SSM couples in the New York and San Francisco metropolitan areas. Stratified purposive sampling was used to include Black (n = 16), White (n = 17), and interracial (Black-White) (n = 15) couples. Twenty-six couples were concordant HIV-negative and 22 were HIV-discordant. Interviews were recorded, transcribed, coded, and analyzed using a grounded theory approach. Some couples described explicit processes, which involved active discussion, while others described implicit processes, where condom-use decisions occurred without any explicit discussion. These processes also differed by race and HIV status. Black couples tended to report condom-use as "just understood." White, HIV-discordant couples decided not to use condoms, with some identifying the HIV-positive partner's suppressed viral load and high CD4 count as deciding factors. After an unplanned episode of UAI, White, HIV-negative couples tended to discontinue condom use while Black HIV-negative couples decided to revert to using condoms. HIV prevention efforts focused on same-sex, male couples must consider the explicit/implicit nature of condom decision-making processes. Understanding differences in these processes and considering relationship dynamics, across race and HIV status, can promote the development of innovative couple-level, HIV prevention interventions. PMID:23912774

  1. Application of the capture-recapture method for estimating number of mobile male sex workers in a port city of Bangladesh.

    PubMed

    Khan, Sharful Islam; Bhuiya, Abbas; Uddin, A S

    2004-03-01

    Male sex workers (MSWs) and sex trades are not new in Bangladesh. Current HIV interventions for MSWs need to be expanded in the major cities, but the number of MSWs needs to be scientifically estimated. Although two-sample capture-recapture surveys are suitable for closed populations, this method was here applied to indirectly estimate the number of mobile MSWs in a conservative social setting, a port city of Bangladesh. Use of the method resulted in an estimation of 248 MSWs (95% confidence interval, 246-250) who picked up clients only at open and known contact venues. This estimate does not, however, reflect the total number as MSWs who worked in unknown hidden venues and could not be reached. Experience suggests that the two-sample capture-recapture method is a simple technique for reliably estimating an unrecognized population. The limitation of this method can be minimized by shortening the time gap between surveys, creating an enabling environment to encounter harassment of MSWs, and offering safety to peer-staff. PMID:15190808

  2. [Multi-month dynamics of the functional condition of organism of normal male northeners of Russia].

    PubMed

    Solonin, Iu G; Markov, A L; Boĭko, E R

    2012-01-01

    In conjunction with the Mars-500 project, 17 male residents (25-46 y.o.) of the North of Russia (62 degrees 40'N) were examined monthly using hard- and software EKOSAN-2007. In the period of June, 2010 through to November, 2011 they visited a standard laboratory to go through comprehensive anthropophysiometric, psychophysiological and physiological investigations at rest and combined with exercise, standing and cold tests aimed at tracking the seasonal responses of the body functional parameters. The larger part of group-average psychomotor, breathing and circulation measurements as well as heart rate variability did not exhibit statistically significant differences between months or seasons. Reliable seasonal variations were documented in the life index, body and cutaneous temperature, myocardium index and regulatory systems activity. A correlation between environmental and some body functional parameters was established. In the course of the multi-month monitoring there were periods when essentially healthy people were diagnosed as prenosologic and even premorbid. Some findings in the functioning of male northerner's organism are clearly attributable to living in the high-altitude area. PMID:23457967

  3. Safe sex versus safe love? Relationship context and condom use among male adolescents in the favelas of Recife, Brazil.

    PubMed

    Juarez, Fatima; Martn, Teresa Castro

    2006-02-01

    This study examined the influence of the relationship context where adolescent sexual activity takes place on contraceptive decisions. The data were collected in a specially designed survey carried out in May 2000 on 1,438 adolescent males aged 13-19 residing in favelas (urban slum areas) of Recife, Brazil. A logistic regression analysis of condom use at last sexual intercourse and a multinomial logit analysis of contraceptive method choice were performed for 678 sexually active adolescents. Educational attainment, degree of knowledge of HIV transmission and prevention, and condom use at first sexual intercourse were found to be significantly associated with current condom use. Regarding the relationship context, the analysis revealed that adolescent males in steady relationships were less likely to use condoms, less likely to regard themselves at risk of HIV infection, and more concerned about pregnancy prevention than adolescents in casual relationships. Differentials in condom use by type of relationship, however, did not result from a higher rejection of contraception by steady partners but from their higher likelihood to rely on other contraceptive methods. Results suggest that prevention campaigns need to take into account the intimate context where adolescents assess potential health risks, and to address the divergent symbolic meanings condoms may have in different types of relationships. If an increase of condom use among stable sexual partners is pursued, public health campaigns might need to romanticize condom use as a sign of love and trust and place more emphasis on the benefits of dual protection. PMID:16502151

  4. 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.

  5. 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

  6. Social network and other correlates of HIV testing: findings from male sex workers and other MSM in Shanghai, China.

    PubMed

    Huang, Z Jennifer; He, Na; Nehl, Eric J; Zheng, Tony; Smith, Brian D; Zhang, Jin; McNabb, Sarah; Wong, Frank Y

    2012-05-01

    Although the Chinese government provides free-of-charge voluntary HIV counseling and testing, HIV testing rates among men who have sex with men (MSM) are reported to be extremely low. This study examines the association of structural and psychosocial factors and social network characteristics with HIV testing behaviors among "money boys" and general MSM in Shanghai. Overall, 28.5% of "money boys" and 50.5% of general MSM had never tested for HIV despite high rates of reported HIV risk behaviors. Factors associated with not testing for HIV included: not knowing of a testing site, limited HIV knowledge, low perceived HIV risk, concern about HIV testing confidentiality, being a closeted gay, not using the Internet, and having a small social network or network with few members who had tested for HIV. Future efforts to promote HIV testing should focus on outreach to general MSM, confidentiality protection, decreasing the stigma of homosexuality, and encouraging peer education and support through the Internet and social networks. PMID:22223298

  7. Male homosexual identities, relationships, and practices among young men who have sex with men in Vietnam: implications for HIV prevention.

    PubMed

    Ngo, Duc Anh; Ross, Michael W; Phan, Ha; Ratliff, Eric A; Trinh, Thang; Sherburne, Lisa

    2009-06-01

    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

  8. 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

  9. Exceptional Use of Sex Pheromones by Parasitoids of the Genus Cotesia: Males Are Strongly Attracted to Virgin Females, but Are No Longer Attracted to or Even Repelled by Mated Females

    PubMed Central

    Xu, Hao; Veyrat, Nathalie; Degen, Thomas; Turlings, Ted C. J.

    2014-01-01

    Sex pheromones have rarely been studied in parasitoids, and it remains largely unknown how male and female parasitoids locate each other. We investigated possible attraction (and repellency) between the sexes of two braconid wasps belonging to the same genus, the gregarious parasitoid, Cotesia glomerata (L.), and the solitary parasitoid, Cotesia marginiventris (Cresson). Males of both species were strongly attracted to conspecific virgin females. Interestingly, in C. glomerata, the males were repelled by mated females, as well as by males of their own species. This repellency of mated females was only evident hours after mating, implying a change in pheromone composition. Males of C. marginiventris were also no longer attracted, but not repelled, by mated females. Females of both species showed no attraction to the odors of conspecific individuals, male or female, and C. glomerata females even appeared to be repelled by mated males. Moreover, the pheromones were found to be highly specific, as males were not attracted by females of the other species. Males of Cotesia glomerata even avoided the pheromones of female Cotesia marginiventris, indicating the recognition of non-conspecific pheromones. We discuss these unique responses in the context of optimal mate finding strategies in parasitoids. PMID:26462821

  10. 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