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Sample records for adult male sex

  1. 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…

  2. Childhood Attachment and Adult Attachment in Incarcerated Adult Male Sex Offenders.

    ERIC Educational Resources Information Center

    Smallbone, Stephen W.; Dadds, Mark R.

    1998-01-01

    Forty-eight incarcerated sex offenders were compared with 16 property offenders and 16 nonoffenders on self-report measures of childhood maternal and paternal attachment and adult attachment. Results suggest that insecure childhood attachments may be related to offending behavior generally and that certain combinations of childhood attachment…

  3. 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

  4. Adolescent and young adult male sex offenders: understanding the role of recidivism.

    PubMed

    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 recidivistic offenders. It is imperative to focus on adolescents and young adults who sexually abuse because they represent a particularly important intervention point in preventing sexual abuse in comparison to older age groups and address the importance of differentiating among youths who sexually abuse, particularly between one-time offenders and recidivistic offenders. Implications for addressing these differences are discussed. PMID:23350537

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

    PubMed

    Kosztolányi, A; Barta, Z; Küpper, C; Székely, 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

  6. 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…

  7. The effects of adult sex ratio on mating competition in male and female guppies (Poecilia reticulata) in two wild populations.

    PubMed

    Chuard, Pierre J C; Brown, Grant E; Grant, James W A

    2016-08-01

    When competing for mates, males typically exhibit higher rates of intrasexual aggression and courtship than females. Operational sex ratio, represented here by adult sex ratio (ASR) as a proxy, is likely the best predictor of this competition, which typically increases between members of one sex as members of the opposite sex become rarer. Moreover, in populations subject to high predation, males often decrease mating competitive behaviour due to predation risk. We explored the combined effects of ASR and population of origin (low vs. high ambient predation risk) on mating competition in male and female wild-caught Trinidadian guppies. Both male and female aggression rates increased with ASR, but the increase for males was only significant in the low-predation population. In regard to male mating tactics, courtship propensity was unaffected by ASR, while the propensity to sneak increased at male-biased ASRs. Guppies from a high predation population had lower aggression rates than their low predation counterpart, but male courtship and sneaking attempts did not differ between populations. Surprisingly, females were just as aggressive as males when competing for mates. These results highlight the trade-offs between antipredator and agonistic behaviour, which may affect sexual selection pressures in wild populations. PMID:27208810

  8. A prospective analysis of juvenile male sex offenders: characteristics and recidivism rates as adults.

    PubMed

    Vandiver, Donna M

    2006-05-01

    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 who was arrested for sexual assault or indecency with a child. The majority of the victims are females with an average age of 8. Although only 13 are rearrested during the follow-up period for a sex offense, more than half of the sample is arrested at least once for a nonsexual offense. The results of a Cox regression indicate that victim age, offender age, and victim sex are significant predictors of recidivism during adulthood. PMID:16574639

  9. Reactions to First Postpubertal Male Same-Sex Sexual Experience in the Kinsey Sample: A Comparison of Minors With Peers, Minors With Adults, and Adults With Adults.

    PubMed

    Rind, Bruce; Welter, Max

    2016-10-01

    Rind and Welter (2014) examined first postpubertal coitus using the Kinsey sample, finding that reactions were just as positive, and no more negative, among minors with adults compared to minors with peers and adults with adults. In the present study, we examined first postpubertal male same-sex sexual experiences in the Kinsey same-sex sample (i.e., participants mostly with extensive postpubertal same-sex behavior), comparing reactions across the same age categories. These data were collected between 1938 and 1961 (M year: 1946). Minors under age 18 years with adults (M ages: 14.0 and 30.5, respectively) reacted positively (i.e., enjoyed the experience "much") often (70 %) and emotionally negatively (e.g., fear, disgust, shame, regret) infrequently (16 %). These rates were the same as adults with adults (M ages: 21.2 and 25.9, respectively): 68 and 16 %, respectively. Minors with peers (M ages: 13.3 and 13.8, respectively) reacted positively significantly more often (82 %) and negatively nominally less often (9 %). Minors with adults reacted positively to intercourse (oral, anal) just as often (69 %) as to outercourse (body contact, masturbation, femoral) (72 %) and reacted emotionally negatively significantly less often (9 vs. 25 %, respectively). For younger minors (≤14) with adults aged 5-19 years older, reactions were just as positive (83 %) as for minors with peers within 1 year of age (84 %) and no more emotionally negative (11 vs. 7 %, respectively). Results are discussed in relation to findings regarding first coitus in the Kinsey sample and to the cultural context particular to Kinsey's time. PMID:27178172

  10. Sex and age differences in hibernation patterns of common hamsters: adult females hibernate for shorter periods than males.

    PubMed

    Siutz, Carina; Franceschini, Claudia; Millesi, Eva

    2016-08-01

    In this study, we investigated the timing and duration of hibernation as well as body temperature patterns in free-ranging common hamsters (Cricetus cricetus) with regard to sex and age differences. Body temperature was recorded using subcutaneously implanted data loggers. The results demonstrate that although immergence and vernal emergence sequences of sex and age groups resembled those of most hibernators, particularly adult females delayed hibernation onset until up to early January. Thus, in contrast to other hibernators, female common hamsters hibernated for shorter periods than males and correspondingly spent less time in torpor. These sex differences were absent in juvenile hamsters. The period between the termination of hibernation and vernal emergence varied among individuals but did not differ between the sex and age groups. This period of preemergence euthermy was related to emergence body mass: individuals that terminated hibernation earlier in spring and had longer euthermic phases prior to emergence started the active season in a better condition. In addition, males with longer periods of preemergence euthermy had larger testes at emergence. In conclusion, females have to rely on sufficient food stores but may adjust the use of torpor in relation to the available external energy reserves, whereas males show a more pronounced energy-saving strategy by hibernating for longer periods. Nonetheless, food caches seem to be important for both males and females as indicated by the euthermic preemergence phase and the fact that some individuals, mainly yearlings, emerged with a higher body mass than shortly before immergence in autumn. PMID:27138337

  11. 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

  12. 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

  13. 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.

  14. 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…

  15. 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)

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

    PubMed Central

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

    2013-01-01

    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

  17. 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

  18. Effect of long-term ingestion of chromium compounds on aggression, sex behavior and fertility in adult male rat.

    PubMed

    Bataineh, H; al-Hamood, M H; Elbetieha, A; Bani Hani, I

    1997-08-01

    The effects of long-term ingestion of chromium chloride (trivalent compound) and potassium dichromate (hexavalent compound) was investigated on sexual behavior, aggressive behavior and fertility in male rats. Adult male rats were exposed to chromium chloride and potassium dichromate in drinking water at a concentration of 1000 ppm for 12 weeks. The exposure of male rats to chromium chloride and potassium dichromate reduced the number of mounts. The exposure of male rats to potassium dichromate increased the time to ejaculation. On the other hand, the exposure of male rats to chromium chloride and potassium dichromate increased the post ejaculatory interval. The number of animals ejaculating were reduced in chromium chloride and potassium dichromate exposed male rats. The exposure of male rats to chromium chloride and potassium dichromate decreased lateralizations, boxing bouts and fights with stud male. The exposure of male rats to chromium chloride and potassium dichromate had no effect on fertility. Testes, seminal vesicle and preputial gland weights were significantly reduced in chromium chloride- and potassium dichromate-exposed males. In conclusion, the long-term ingestion of chromium chloride and potassium dichromate would have adverse effects on sexual behavior and territorial aggression in adult male rat. PMID:9292274

  19. A Sex-Linked Gene Controlling the Onset of Sexual Maturity in Female and Male Platyfish (XIPHOPHORUS MACULATUS), Fecundity in Females and Adult Size in Males

    PubMed Central

    Kallman, Klaus D.; Borkoski, Valerie

    1978-01-01

    A sex-linked gene, P, controls the onset of sexual maturity in the platyfish, Xiphophorus maculatus. The activity of this gene is correlated with the age and size at which the gonadotropic zone of the adenohypophysis differentiates and becomes physiologically active. Immature fish of all genotypes grow at the same rate; however, as adults, males with "early" genotypes are significantly smaller than males of "late" genotypes, since growth rate declines strongly under the influence of androgenic hormone. Five alleles, P1... P5, have been identified from natural populations that under controlled conditions cause gonad maturation between eight and 73 weeks. P1P1 males become mature at eight weeks and 21 mm, P2P2 and P3P3 males between eleven and 13.5 weeks and 25 to 29 mm, and P4P4 males at 25 weeks and 37 mm. Since P5 is X-linked, no males homozygous for P5 could be produced. The difference between P2 and P3 is largely based upon their interaction with P5. P3P5 males mature at 17.5 weeks and 33.5 mm and P2P5 males at 28 weeks and 38 mm. The rate of transformation of the unmodified anal fin into a gonopodium, which is under androgenic control, is directly related to the age at initiation of sexual maturity, ranging from 3.2 weeks in P1P1 males to seven weeks in P2P 5 males. These differences may reflect different levels of circulating gonadotropic and androgenic hormones.—In two genotypes of females, initiation of vitellogenesis was closely correlated with size and this critical size was independent of age (e.g., 21 mm for P1P1 ). In a third genotype (P1P5) the minimum size for vitellogenesis decreased with increasing age, so that females would mature as early as eleven weeks, provided they had attained at least 29 mm, but at 25 weeks even females as small as 23 mm possessed ripe gonads. For P5P5 females, which become mature between 34 and 73 weeks of age, there is no correlation between size and initiation of vitellogenesis. In all four genotypes of females examined

  20. Serum sex hormone levels in different severity of male adult obstructive sleep apnea-hypopnea syndrome in East Asians.

    PubMed

    Dong, Jia-Qi; Chen, Xiong; Xiao, Ying; Zhang, Rui; Niu, Xun; Kong, Wei-Jia

    2015-08-01

    Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a serious health issue, which can impact the hormone secretion. The aim of this study is to analyze the relationship between serum sex hormone concentrations and different severity degree of OSAHS, and to evaluate the influence of OSAHS on sex hormone levels. We enrolled 116 subjects who were subjected to polysomnography (PSG). They were divided into three groups: control group (n=10) [apnea hypopnea index (AHI) <5/h], mild-moderate OSAHS group (n=15) (5≤AHI<30/h), and severe OSAHS group (n=91) (AHI≥30/h). The patients in OSAHS group were subdivided into obesity and non-obesity subgroups. The parameters such as AHI, body mass index (BMI), lowest oxygen saturation (LSaO2), and mean oxygen saturation (MSaO2) were recorded. Serum levels of testosterone, polactin, estradiol, follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined in the morning immediately after waking up. Mean levels of hormones were compared among groups. The correlation between hormone levels and sleep-breathing parameters was analyzed. No significant differences in serum sex hormone levels were found among control, mild-moderate OSAHS, and severe OSAHS groups (P>0.05). There was no correlation between AHI and sex hormone levels (P>0.05). Testosterone was significantly negatively correlated with BMI (P<0.05). These results suggested that BMI might have a direct effect on testosterone level, and it might be an important factor affecting testosterone level in male OSAHS patients, and there may be no correlation between severity of OSAHS and sex hormones levels. PMID:26223926

  1. Research directions in male sex work.

    PubMed

    Browne, J; Minichiello, V

    1996-01-01

    This paper provides a critical review of the literature relating to male sex work and outlines approaches to theorizing about and researching male sex work. The adequacy of these models to explain the male sex work industry is discussed. The literature reveals that earlier studies conceptualized male sex work as deviance and focused on the individual sex worker and his reasons for engaging in sex work. Although the research agenda has recently moved away from the individual sex worker towards the sex work industry, the focus of the investigation continues to be from a deviance rather than a work perspective. A number of aspects of male sex work have received little attention in the literature. These include the interpersonal dialogues and power relations that constitute the commercial sexual negotiation, the role of political and economic forces, and expressions of male sexuality within the practice of commercial sex. The paper suggests future research directions and argues that researchers need to draw on the strengths of the male sex work community in order to promote safe sex practices in commercial researchers need to draw on the strengths of the male sex work community in order to promote safe sex practices in commercial sexual settings. PMID:8905528

  2. Determining circadian response of adult male Acrobasis nuxvorella (Lepidoptera: Pyralidae) to synthetic sex attractant pheromone through time-segregated trapping with a new clockwork timing trap.

    PubMed

    Stevenson, Douglass E; Harris, Marvin K

    2009-12-01

    Mate finding is a key lifecycle event for the pecan nut casebearer, Acrobasis nuxvorella Neunzig, as it is for virtually all Lepidoptera, many of which rely on long-range, species-specific sex pheromones, regulated largely by circadian clocks. Adult male moths were trapped at discrete time intervals during the first two seasonal flights for 6 yr to determine times of peak activity associated with male response to pheromones. From 1997 to 2002, the Harris-Coble automated clockwork timing trap was used for hourly time-segregated sampling. Analysis of variance with linear contrasts determined that circadian response of A. nuxvorella males to pecan nut casebearer pheromone began at approximately 2100 hours, the first hour of total darkness, lasting for 6-7 h. It peaked from midnight to 0400 hours and ended at the onset of morning twilight, approximately 0500 hours. The hours of peak activity are hours of minimal bat predation. The study shows that pecan nut casebearer males become responsive to pheromone several hours before females start calling and remain responsive for at least 1 h after they stop. The extended response period conforms to studies of other polygamous Lepidoptera in which a selective advantage is conferred on early responding males in scramble competition for available females. PMID:20021765

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

    PubMed 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

  4. 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.

  5. Programming of Dopaminergic Neurons by Neonatal Sex Hormone Exposure: Effects on Dopamine Content and Tyrosine Hydroxylase Expression in Adult Male Rats

    PubMed Central

    Espinosa, Pedro; Silva, Roxana A.; Sanguinetti, Nicole K.; Venegas, Francisca C.; Riquelme, Raul; González, Luis F.; Cruz, Gonzalo; Renard, Georgina M.; Moya, Pablo R.; Sotomayor-Zárate, Ramón

    2016-01-01

    We sought to determine the long-term changes produced by neonatal sex hormone administration on the functioning of midbrain dopaminergic neurons in adult male rats. Sprague-Dawley rats were injected subcutaneously at postnatal day 1 and were assigned to the following experimental groups: TP (testosterone propionate of 1.0 mg/50 μL); DHT (dihydrotestosterone of 1.0 mg/50 μL); EV (estradiol valerate of 0.1 mg/50 μL); and control (sesame oil of 50 μL). At postnatal day 60, neurochemical studies were performed to determine dopamine content in substantia nigra-ventral tegmental area and dopamine release in nucleus accumbens. Molecular (mRNA expression of tyrosine hydroxylase) and cellular (tyrosine hydroxylase immunoreactivity) studies were also performed. We found increased dopamine content in substantia nigra-ventral tegmental area of TP and EV rats, in addition to increased dopamine release in nucleus accumbens. However, neonatal exposure to DHT, a nonaromatizable androgen, did not affect midbrain dopaminergic neurons. Correspondingly, compared to control rats, levels of tyrosine hydroxylase mRNA and protein were significantly increased in TP and EV rats but not in DHT rats, as determined by qPCR and immunohistochemistry, respectively. Our results suggest an estrogenic mechanism involving increased tyrosine hydroxylase expression, either by direct estrogenic action or by aromatization of testosterone to estradiol in substantia nigra-ventral tegmental area. PMID:26904299

  6. 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…

  7. Sex Differences in Facial Scanning: Similarities and Dissimilarities between Infants and Adults

    ERIC Educational Resources Information Center

    Rennels, Jennifer L.; Cummings, Andrew J.

    2013-01-01

    When face processing studies find sex differences, male infants appear better at face recognition than female infants, whereas female adults appear better at face recognition than male adults. Both female infants and adults, however, discriminate emotional expressions better than males. To investigate if sex and age differences in facial scanning…

  8. 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

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

    PubMed

    Le Galliard, Jean-François; Fitze, Patrick S; Ferrière, Régis; Clobert, Jean

    2005-12-13

    The adult sex ratio (ASR) is a key parameter of the demography of human and other animal populations, yet the causes of variation in ASR, how individuals respond to this variation, and how their response feeds back into population dynamics remain poorly understood. A prevalent hypothesis is that ASR is regulated by intrasexual competition, which would cause more mortality or emigration in the sex of increasing frequency. Our experimental manipulation of populations of the common lizard (Lacerta vivipara) shows the opposite effect. Male mortality and emigration are not higher under male-biased ASR. Rather, an excess of adult males begets aggression toward adult females, whose survival and fecundity drop, along with their emigration rate. The ensuing prediction that adult male skew should be amplified and total population size should decline is supported by long-term data. Numerical projections show that this amplifying effect causes a major risk of population extinction. In general, such an "evolutionary trap" toward extinction threatens populations in which there is a substantial mating cost for females, and environmental changes or management practices skew the ASR toward males. PMID:16322105

  10. The Effects of Sex-Labelling on Adult-Infant Interactions.

    ERIC Educational Resources Information Center

    Armstrong, Suzy; Karr-Kidwell, PJ

    The influence of sex-labelling on adult-infant interactions is explored in this study. It is hypothesized that, when introduced to a single infant identified as either male or female, adults will (1) offer more masculine sex-stereotyped toys to the infant perceived to be male; (2) offer more feminine sex-stereotyped toys to the infant perceived to…

  11. 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

  12. Sexual Assault of Adult Males.

    ERIC Educational Resources Information Center

    Stermac, Lana; And Others

    1996-01-01

    Examines the circumstances and characteristics of sexual assaults against adult males presenting to a crisis unit in a large metropolitan area. Most victims were young gay men, many of whom had physical or cognitive disabilities making them particularly vulnerable. Results suggest a need for increased awareness of acquaintance sexual assault in…

  13. Sex differences in adrenocortical structure and function. XVI. Stereological and karyometric studies on the cortex of the suprarenal gland of intact adult male and female Mongolian gerbils (Meriones unguiculatus).

    PubMed Central

    Malendowicz, L K

    1984-01-01

    The histological structure of intact adult male and female Mongolian gerbil (Meriones unguiculatus) suprarenal cortex has been described, and quantitative stereological and karyometric studies were performed. The weight of the gland relative to body weight was higher in female than in male gerbils, but the volume of the gland was similar in both sexes. The relative volume of the zona reticularis was higher in the female, while no sex difference was observed in the absolute volume of all suprarenal components (expressed in mm3). In all cortical zones, average cell volume was higher in the female; the nuclear volume of the zona glomerulosa and zona reticularis were also higher in the female. In the zona fasciculata, some large cells with large nuclei (greater than 210 micrometers 3) were observed. These are probably polyploid cells and have not been described in other species. The suprarenal cortex of the male gerbil contained more parenchymal cells than that of the female, the difference being dependent upon variation in the number of cells in the zona fasciculata and zona reticularis. Despite these structural differences, gland homogenates from male and female animals secreted similar amounts of cortisol and the plasma levels in the two sexes were the same. Images Fig. 1 PMID:6490533

  14. Sex differences in adrenocortical structure and function. XVI. Stereological and karyometric studies on the cortex of the suprarenal gland of intact adult male and female Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Malendowicz, L K

    1984-10-01

    The histological structure of intact adult male and female Mongolian gerbil (Meriones unguiculatus) suprarenal cortex has been described, and quantitative stereological and karyometric studies were performed. The weight of the gland relative to body weight was higher in female than in male gerbils, but the volume of the gland was similar in both sexes. The relative volume of the zona reticularis was higher in the female, while no sex difference was observed in the absolute volume of all suprarenal components (expressed in mm3). In all cortical zones, average cell volume was higher in the female; the nuclear volume of the zona glomerulosa and zona reticularis were also higher in the female. In the zona fasciculata, some large cells with large nuclei (greater than 210 micrometers 3) were observed. These are probably polyploid cells and have not been described in other species. The suprarenal cortex of the male gerbil contained more parenchymal cells than that of the female, the difference being dependent upon variation in the number of cells in the zona fasciculata and zona reticularis. Despite these structural differences, gland homogenates from male and female animals secreted similar amounts of cortisol and the plasma levels in the two sexes were the same. PMID:6490533

  15. Sex differences in DNA methylation and expression in zebrafish brain: a test of an extended 'male sex drive' hypothesis.

    PubMed

    Chatterjee, Aniruddha; Lagisz, Malgorzata; Rodger, Euan J; Zhen, Li; Stockwell, Peter A; Duncan, Elizabeth J; Horsfield, Julia A; Jeyakani, Justin; Mathavan, Sinnakaruppan; Ozaki, Yuichi; Nakagawa, Shinichi

    2016-09-30

    The sex drive hypothesis predicts that stronger selection on male traits has resulted in masculinization of the genome. Here we test whether such masculinizing effects can be detected at the level of the transcriptome and methylome in the adult zebrafish brain. Although methylation is globally similar, we identified 914 specific differentially methylated CpGs (DMCs) between males and females (435 were hypermethylated and 479 were hypomethylated in males compared to females). These DMCs were prevalent in gene body, intergenic regions and CpG island shores. We also discovered 15 distinct CpG clusters with striking sex-specific DNA methylation differences. In contrast, at transcriptome level, more female-biased genes than male-biased genes were expressed, giving little support for the male sex drive hypothesis. Our study provides genome-wide methylome and transcriptome assessment and sheds light on sex-specific epigenetic patterns and in zebrafish for the first time. PMID:27259666

  16. Sex role strain among kibbutz adolescents and adults: A developmental perspective.

    PubMed

    Snarey, J; Friedman, K; Blasi, J

    1986-06-01

    In spite of a commitment to equality, the kibbutz is a male-dominated society with highly differentiated sex roles. Has this gap between ideals and reality created sex role strain for kibbutz-born adolescents and adults? Previous kibbutz studies have suggested that sex role strain may be the most intense among adult kibbutz women. Based on Erik Erikson's developmental model, however, we hypothesized that adolescent females would experience significantly greater sex role strain than other kibbutz members, including adult women. Adolescent and adult males and females were tested using Loevinger's ego development test. The sex role items of the test were used to construct a new measure of sex role strain. The global index included the following submeasures: avoidance of sex role issues; expression of intellectual, emotional, or behavioral sex role conflict; and evaluative attitudes toward male roles and female roles. Significant cohort or sex differences were found on the global index and on all submeasures of sex role strain. The findings indicate that sex role strain is greatest among adolescent females, followed by adolescent males. Adult kibbutz women, however, are significantly more likely to focus their dissatisfaction in the area of actual role behavior rather than in terms of how they intellectually conceptualize kibbutz sex roles, as is the case for adolescents and adult males. PMID:24301699

  17. Identification of a sex pheromone from male yellow mealworm beetles, Tenebrio molitor.

    PubMed

    Bryning, Gareth P; Chambers, John; Wakefield, Maureen E

    2005-11-01

    The sex pheromone released by the adult female Tenebrio molitor, 4-methyl-1-nonanol, is well known. In addition, there is evidence that adult males release a pheromone that attracts females. The purpose of the present study was to isolate and identify male-released pheromone(s). Emissions from virgin adult males and females were collected on filter paper and extracted with pentane. Extracts were analyzed by gas chromatography-mass spectrometry. One male-specific compound was detected and identified as (Z)-3-dodecenyl acetate (Z3-12:Ac). In arena bioassays, E3-12:Ac was attractive to females only, at 1 and 10 microg doses. E3-12:Ac was also attractive to females at a 10-microg dose. The presence of both male and female pheromones, each attracting the opposite sex, may contribute to maintaining a high-density population of both sexes. PMID:16273437

  18. The genetic sex-determination system predicts adult sex ratios in tetrapods.

    PubMed

    Pipoly, Ivett; Bókony, Veronika; Kirkpatrick, Mark; Donald, Paul F; Székely, Tamás; Liker, András

    2015-11-01

    The adult sex ratio (ASR) has critical effects on behaviour, ecology and population dynamics, but the causes of variation in ASRs are unclear. Here we assess whether the type of genetic sex determination influences the ASR using data from 344 species in 117 families of tetrapods. We show that taxa with female heterogamety have a significantly more male-biased ASR (proportion of males: 0.55 ± 0.01 (mean ± s.e.m.)) than taxa with male heterogamety (0.43 ± 0.01). The genetic sex-determination system explains 24% of interspecific variation in ASRs in amphibians and 36% in reptiles. We consider several genetic factors that could contribute to this pattern, including meiotic drive and sex-linked deleterious mutations, but further work is needed to quantify their effects. Regardless of the mechanism, the effects of the genetic sex-determination system on the adult sex ratio are likely to have profound effects on the demography and social behaviour of tetrapods. PMID:26444239

  19. Effects of date palm pollen (Phoenix dactylifera L.) and Astragalus ovinus on sperm parameters and sex hormones in adult male rats

    PubMed Central

    Mehraban, Fouad; Jafari, Mehrzad; Akbartabar Toori, Mehdi; Sadeghi, Hossein; Joodi, Behzad; Mostafazade, Mostafa; Sadeghi, Heibatollah

    2014-01-01

    Background: Date Palm Pollen (DPP) and Astragalus genus are used in some countries for the treatment of infertility. Objective: This study was designed to investigate effects of DPP and Astragalus ovinus (A.Ovinus) on fertility in healthy adult male rats. Materials and Methods: Thirty-six rats were divided into six groups (n=6) including control and five treatment groups. DPP (120, 240 and 360 mg/kg) and A.ovinus (100, 500 mg/ kg) were orally given to the treatment groups. After thirty-five days, blood samples were taken to determine serum levels of FSH, LH, testosterone and estradiol. Weight of testis and epididymis, sperm count, sperm motility, seminiferous tubules diameter (STD), germinal cell layer thickness (GCLT), sertoli, leydig and spermatogonia cells were also evaluated. Results: DPP at the of 120 and 240 mg/kg doses significantly raised the ratio of testis or epididymis to body weight, sperm count, sperm motility , and estradiol level compared to the control group (p<0.05). LH and testosterone levels only noticeably increased at 120 mg/kg of DPP (p<0.01 and p<0.001 respectively). STD increased in the three applied doses (p=0.001). A. ovinus extract at the indicated doses produced a significant reduction in the ratio of testis or epididymis to body weight and sperm motility (p<0.05). Sperm count, spermatogonia, leydig cells and FSH level decreased at dose of 500 mg/kg. Furthermore, GCLT, spermatogonia cells, and serum estradiol level increased at 100 mg/kg dose of A. ovinus. Conclusion: Our findings indicate that DPP could improve fertility factors, while A.ovinus can exhibit deleterious effects on gonad and sperm parameters in rats. PMID:25469129

  20. 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...

  1. Understanding the New Context of the Male Sex Work Industry

    ERIC Educational Resources Information Center

    Scott, John; Minichiello, Victor; Marino, Rodrigo; Harvey, Glenn P.; Jamieson, Maggie; Browne, Jan

    2005-01-01

    The article reviews past and recent research on male sex work to offer a context to understand violence in the industry. It provides a critical review of research to show, first, the assumptions made about male sex workers and violence and, second, how such discourses have shaped thinking on the topic. The article presents a case study and…

  2. Children's and Adults' Recall of Sex-Stereotyped Toy Pictures: Effects of Presentation and Memory Task

    ERIC Educational Resources Information Center

    Cherney, Isabelle D.

    2005-01-01

    Gender schema theories predict a memory bias toward sex-congruent information. The present study examined how presentation of stimuli and encoding conditions influence gender schematic processing in children and adults. One hundred and sixty 5- to 13-year olds and adult males and females viewed 36 sex-stereotyped toy pictures that were presented…

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

    PubMed Central

    Córdoba-Aguilar, Alex; Munguía-Steyer, Roberto

    2013-01-01

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

  4. The adult well male examination.

    PubMed

    Heidelbaugh, Joel J; Tortorello, Michelle

    2012-05-15

    The adult well male examination should incorporate evidence-based guidance toward the promotion of optimal health and well-being, including screening tests shown to improve health outcomes. Nearly one-third of men report not having a primary care physician. The medical history should include substance use; risk factors for sexually transmitted infections; diet and exercise habits; and symptoms of depression. Physical examination should include blood pressure and body mass index screening. Men with sustained blood pressures greater than 135/80 mm Hg should be screened for diabetes mellitus. Lipid screening is warranted in all men 35 years and older, and in men 20 to 34 years of age who have cardiovascular risk factors. Ultrasound screening for abdominal aortic aneurysm should occur between 65 and 75 years of age in men who have ever smoked. There is insufficient evidence to recommend screening men for osteoporosis or skin cancer. The U.S. Preventive Services Task Force has provisionally recommended against prostate-specific antigen-based screening for prostate cancer because the harms of testing and overtreatment outweigh potential benefits. Screening for colorectal cancer should begin at 50 years of age in men of average risk and continue until at least 75 years of age. Screening should be performed by high-sensitivity fecal occult blood testing every year, flexible sigmoidoscopy every five years combined with [corrected] fecal occult blood testing every three years. [corrected]. The U.S. Preventive Services Task Force recommends against screening for testicular cancer and chronic obstructive pulmonary disease. Immunizations should be recommended according to guidelines from the Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention. PMID:22612046

  5. Sex-different response in growth traits to resource heterogeneity explains male-biased sex ratio

    NASA Astrophysics Data System (ADS)

    Matsushita, Michinari; Takao, Mikako; Makita, Akifumi

    2016-08-01

    In dioecious plants, differences in growth traits between sexes in a response to micro-environmental heterogeneity may affect sex ratio bias and spatial distributions. Here, we examined sex ratios, stem growth traits and spatial distribution patterns in the dioecious clonal shrub Aucuba japonica var. borealis, in stands with varying light intensities. We found that male stems were significantly more decumbent (lower height/length ratio) but female stems were upright (higher height/length ratio). Moreover, we found sex-different response in stem density (no. of stems per unit area) along a light intensity gradient; in males the stem density increased with increases in canopy openness, but not in females. The higher sensitivity of males in increasing stem density to light intensity correlated with male-biased sex ratio; fine-scale sex ratio was strongly male-biased as canopy openness increased. There were also differences between sexes in spatial distributions of stems. Spatial segregation of sexes and male patches occupying larger areas than female patches might result from vigorous growth of males under well-lit environments. In summary, females and males showed different growth responses to environmental variation, and this seemed to be one of possible causes for the sex-differential spatial distributions and locally biased sex ratios.

  6. Sex-biased survival predicts adult sex ratio variation in wild birds

    PubMed Central

    Székely, Tamás; Liker, András; Freckleton, Robert P.; Fichtel, Claudia; Kappeler, Peter M.

    2014-01-01

    Adult sex ratio (ASR) is a central concept in population demography and breeding system evolution, and has implications for population viability and biodiversity conservation. ASR exhibits immense interspecific variation in wild populations, although the causes of this variation have remained elusive. Using phylogenetic analyses of 187 avian species from 59 families, we show that neither hatching sex ratios nor fledging sex ratios correlate with ASR. However, sex-biased adult mortality is a significant predictor of ASR, and this relationship is robust to 100 alternative phylogenetic hypotheses, and potential ecological and life-history confounds. A significant component of adult mortality bias is sexual selection acting on males, whereas increased reproductive output predicts higher mortality in females. These results provide the most comprehensive insights into ASR variation to date, and suggest that ASR is an outcome of selective processes operating differentially on adult males and females. Therefore, revealing the causes of ASR variation in wild populations is essential for understanding breeding systems and population dynamics. PMID:24966308

  7. Sex-biased survival predicts adult sex ratio variation in wild birds.

    PubMed

    Székely, Tamás; Liker, András; Freckleton, Robert P; Fichtel, Claudia; Kappeler, Peter M

    2014-08-01

    Adult sex ratio (ASR) is a central concept in population demography and breeding system evolution, and has implications for population viability and biodiversity conservation. ASR exhibits immense interspecific variation in wild populations, although the causes of this variation have remained elusive. Using phylogenetic analyses of 187 avian species from 59 families, we show that neither hatching sex ratios nor fledging sex ratios correlate with ASR. However, sex-biased adult mortality is a significant predictor of ASR, and this relationship is robust to 100 alternative phylogenetic hypotheses, and potential ecological and life-history confounds. A significant component of adult mortality bias is sexual selection acting on males, whereas increased reproductive output predicts higher mortality in females. These results provide the most comprehensive insights into ASR variation to date, and suggest that ASR is an outcome of selective processes operating differentially on adult males and females. Therefore, revealing the causes of ASR variation in wild populations is essential for understanding breeding systems and population dynamics. PMID:24966308

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

    PubMed

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

    2015-08-01

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

  9. 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

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

    PubMed

    Torres, R; Drummond, H

    1999-01-01

    When the costs of rearing males and females differ progeny sex ratios are expected to be biased toward the less expensive sex. Blue-footed booby (Sula nebouxii) females are larger and roughly 32% heavier than males, thus presumably more costly to rear. We recorded hatching and fledging sex ratios in 1989, and fledging sex ratios during the next 5 years. In 1989, the sample of 751 chicks showed male bias at hatching (56%) and at fledging (57% at 90 days). Fledging sex ratios during the five subsequent reproductive seasons were at unity (1 year) or male-biased, varying from 56% to 70%. Male bias was greater during years when mean sea surface temperature was warmer and food was presumably in short supply. During two warm-water years (only) fledging sex ratio varied with hatching date. Proportions of male fledglings increased with date from 0.48 to 0.73 in 1994, and from 0.33 to 0.79 in 1995. Similar results were obtained when the analysis was repeated using only broods with no nestling mortality, suggesting that the overall increase in the proportion of males over the season was the result of sex ratio adjustments at hatching. The male-biased sex ratio, and the increased male bias during poor breeding conditions supports the idea that daughters may be more costly than sons, and that their relative cost increases in poor conditions. PMID:20135156

  11. 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.

  12. Group Work Practice with Transgendered Male to Female Sex Workers.

    ERIC Educational Resources Information Center

    Klein, Rebecca

    1999-01-01

    Examines group work with transgendered male-to-female adolescents who engage in sex work. Provides an overview of the role that sex work plays in the lives of some transgendered youth, using case examples, and offers guidance for those utilizing group work approaches with transgendered adolescents. Discusses homelessness and institutionalization,…

  13. Sex Differences in Adults' Motivation to Achieve

    ERIC Educational Resources Information Center

    van der Sluis, Sophie; Vinkhuyzen, Anna A. E.; Boomsma, Dorret I.; Posthuma, Danielle

    2010-01-01

    Achievement motivation is considered a prerequisite for success in academic as well as non-academic settings. We studied sex differences in academic and general achievement motivation in an adult sample of 338 men and 497 women (ages 18-70 years). Multi-group covariance and means structure analysis (MG-CMSA) for ordered categorical data was used…

  14. Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior.

    PubMed

    Meier, Madeline H; Slutske, Wendy S; Heath, Andrew C; Martin, Nicholas G

    2011-05-01

    Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior were examined in a large community sample of 6,383 adult male, female, and opposite-sex twins. Retrospective reports of childhood conduct disorder (prior to 18 years of age) were obtained when participants were approximately 30 years old, and lifetime reports of adult antisocial behavior (antisocial behavior after 17 years of age) were obtained 8 years later. Results revealed that either the genetic or the shared environmental factors influencing childhood conduct disorder differed for males and females (i.e., a qualitative sex difference), but by adulthood, these sex-specific influences on antisocial behavior were no longer apparent. Further, genetic and environmental influences accounted for proportionally the same amount of variance in antisocial behavior for males and females in childhood and adulthood (i.e., there were no quantitative sex differences). Additionally, the stability of antisocial behavior from childhood to adulthood was slightly greater for males than females. Though familial factors accounted for more of the stability of antisocial behavior for males than females, genetic factors accounted for the majority of the covariation between childhood conduct disorder and adult antisocial behavior for both sexes. The genetic influences on adult antisocial behavior overlapped completely with the genetic influences on childhood conduct disorder for both males and females. Implications for future twin and molecular genetic studies are discussed. PMID:21319923

  15. Hands as Sex Cues: Sensitivity Measures, Male Bias Measures, and Implications for Sex Perception Mechanisms

    PubMed Central

    Gaetano, Justin; van der Zwan, Rick; Blair, Duncan; Brooks, Anna

    2014-01-01

    Sex perceptions, or more particularly, sex discriminations and sex categorisations, are high-value social behaviours. They mediate almost all inter-personal interactions. The two experiments reported here had the aim of exploring some of the basic characteristics of the processes giving rise to sex perceptions. Experiment 1 confirmed that human hands can be used as a cue to an individual’s sex even when colour and texture cues are removed and presentations are brief. Experiment 1 also showed that when hands are sexually ambiguous observers tend to classify them as male more often than female. Experiment 2 showed that “male bias” arises not from sensitivity differences but from differences in response biases. Observers are conservative in their judgements of targets as female but liberal in their judgements of targets as male. These data, combined with earlier reports, suggest the existence of a sex-perception space that is cue-invariant. PMID:24603615

  16. Hands as sex cues: sensitivity measures, male bias measures, and implications for sex perception mechanisms.

    PubMed

    Gaetano, Justin; van der Zwan, Rick; Blair, Duncan; Brooks, Anna

    2014-01-01

    Sex perceptions, or more particularly, sex discriminations and sex categorisations, are high-value social behaviours. They mediate almost all inter-personal interactions. The two experiments reported here had the aim of exploring some of the basic characteristics of the processes giving rise to sex perceptions. Experiment 1 confirmed that human hands can be used as a cue to an individual's sex even when colour and texture cues are removed and presentations are brief. Experiment 1 also showed that when hands are sexually ambiguous observers tend to classify them as male more often than female. Experiment 2 showed that "male bias" arises not from sensitivity differences but from differences in response biases. Observers are conservative in their judgements of targets as female but liberal in their judgements of targets as male. These data, combined with earlier reports, suggest the existence of a sex-perception space that is cue-invariant. PMID:24603615

  17. Chinmo is sufficient to induce male fate in somatic cells of the adult Drosophila ovary.

    PubMed

    Ma, Qing; de Cuevas, Margaret; Matunis, Erika L

    2016-03-01

    Sexual identity is continuously maintained in specific differentiated cell types long after sex determination occurs during development. In the adult Drosophila testis, the putative transcription factor Chronologically inappropriate morphogenesis (Chinmo) acts with the canonical male sex determinant DoublesexM (Dsx(M)) to maintain the male identity of somatic cyst stem cells and their progeny. Here we find that ectopic expression of chinmo is sufficient to induce a male identity in adult ovarian somatic cells, but it acts through a Dsx(M)-independent mechanism. Conversely, the feminization of the testis somatic stem cell lineage caused by loss of chinmo is enhanced by expression of the canonical female sex determinant Dsx(F), indicating that chinmo acts in parallel with the canonical sex determination pathway to maintain the male identity of testis somatic cells. Consistent with this finding, ectopic expression of female sex determinants in the adult testis disrupts tissue morphology. The miRNA let-7 downregulates chinmo in many contexts, and ectopic expression of let-7 in the adult testis is sufficient to recapitulate the chinmo loss-of-function phenotype, but we find no apparent phenotypes upon removal of let-7 in the adult ovary or testis. Our finding that chinmo is necessary and sufficient to promote a male identity in adult gonadal somatic cells suggests that the sexual identity of somatic cells can be reprogrammed in the adult Drosophila ovary as well as in the testis. PMID:26811385

  18. Embryonic temperature and gonadal sex organize male-typical sexual and aggressive behavior in a lizard with temperature-dependent sex determination.

    PubMed

    Rhen, T; Crews, D

    1999-10-01

    Temperature during embryonic development determines gonadal sex in the leopard gecko, Eublepharis macularius. Moreover, both embryonic temperature and gonadal sex influence adult behavior. Yet it remains unclear whether the effects of embryonic temperature and gonadal sex on behavior are irreversibly organized during development. To address this question, we gonadectomized adult females and males generated from a temperature that produces mostly females (30 C) and a temperature that produces mostly males (32.5 C). Females and males from both temperatures were then treated with equivalent levels of various sex steroids. We found that both embryonic temperature and gonadal sex had persistent effects on the expression of male-typical sexual and aggressive behaviors. For example, adult females do not scent mark and display very little courtship and mounting behavior even when treated with levels of hormones (primarily androgens) that activate these behaviors in males. In contrast, species-typical aggressive displays were less sex specific and were activated by both dihydrotestosterone and testosterone (T) in males and by T in females. Nevertheless, the average duration of aggressive displays was significantly shorter in T-treated females than that in T-treated males. With regard to submissive behavior, androgens decreased flight behavior in males, but had no effect in females. Embryonic temperature had enduring effects on certain behaviors in males. For instance, males from a male-biased embryonic temperature scent-marked more than males from a female-biased embryonic temperature when treated with dihydrotestosterone or T. Conversely, and across hormone treatments, males from a female-biased embryonic temperature mounted more than males from a male-biased embryonic temperature. Finally, treatment with 17beta-estradiol decreased submissive behavior in males from a male-biased embryonic temperature compared with that in males from a female-biased embryonic temperature

  19. 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.

  20. Sex Differences in Seoul Virus Infection Are Not Related to Adult Sex Steroid Concentrations in Norway Rats

    PubMed Central

    Klein, Sabra L.; Bird, Brian H.; Glass, Gregory E.

    2000-01-01

    Field studies of hantavirus infection in rodents report that a higher percentage of infected individuals are males than females. To determine whether males were more susceptible to hantavirus infection than females, adult male and female Long Evans rats (Rattus norvegicus) were inoculated with doses of Seoul virus ranging from 10−4 to 106 PFU. The 50% infective doses (ID50) were not significantly different for male and female rats (100.05 and 100.8 PFU, respectively). To determine whether sex differences in response to infection were related to circulating sex steroid hormones, sex steroid concentrations were manipulated and antibody responses and virus shedding were assessed following inoculation with the ID90. Regardless of hormone treatment, males had higher anti-Seoul virus immunoglobulin G (IgG) and IgG2a (i.e., Th1) responses than females and IgG1 (i.e., Th2) responses similar to those of females. Males also shed virus in saliva and feces longer than females. Manipulation of sex steroids in adulthood did not alter immune responses or virus shedding, suggesting that sex steroids may organize adult responses to hantavirus earlier during ontogeny. PMID:10933735

  1. Same-Sex Behavior and Health Indicators of Sexually Experienced Filipino Young Adults

    PubMed Central

    Cheng, Chia-Hsin Emily; Perez, Tita Lorna; Cochran, Susan D.

    2015-01-01

    The Philippines is one of seven countries in which HIV incidence has recently increased—much of this increase has been among men who have sex with men. Despite this trend, knowledge on sexuality and same-sex behaviors in the Philippines is limited. This study examines same-sex behavior, sexual outcomes, substance use, and psychological distress among young adults participating in the 2005 Cebu Longitudinal Health and Nutrition Survey (CLHNS). We use gender-stratified, multivariate models to compare young adults who reported same-sex behaviors and those who did not. Among a cohort of 1,912 Filipino young adults (ages 20–22), 58.2% were sexually experienced and 15.1% of them reported same-sex sexual contacts or romantic relationships. Compared to females, more males reported same-sex sexual contact (19.4 vs. 2.3 %) or same-sex romantic relationships (9.2 vs. 4.1 %). Young adults reporting same-sex behavior had higher odds of smoking, drug use, perceived stress, and more sexual partners as compared to their peers. Males who reported same-sex behavior initiated sex earlier than those males who did not report same-sex behaviors. There were no significant differences in depressive distress. Earlier sexual initiation and higher levels of substance use among Filipino young adults engaging in same-sex behavior highlight the need to address unique health issues within this population. Mixed findings for depressive distress and perceived stress indicate that further investigation is needed to explore the potential impacts of same-sex status on mental health outcomes, particularly in lower- and middle-income countries such as the Philippines. PMID:25416159

  2. Same-Sex Behavior and Health Indicators of Sexually Experienced Filipino Young Adults.

    PubMed

    Cheng, Chia-Hsin Emily; Gipson, Jessica D; Perez, Tita Lorna; Cochran, Susan D

    2016-08-01

    The Philippines is one of seven countries in which HIV incidence has recently increased-much of this increase has been among men who have sex with men. Despite this trend, knowledge on sexuality and same-sex behaviors in the Philippines is limited. This study examines same-sex behavior, sexual outcomes, substance use, and psychological distress among young adults participating in the 2005 Cebu Longitudinal Health and Nutrition Survey (CLHNS). We use gender-stratified, multivariate models to compare young adults who reported same-sex behaviors and those who did not. Among a cohort of 1,912 Filipino young adults (ages 20-22), 58.2 % were sexually experienced and 15.1 % of them reported same-sex sexual contacts or romantic relationships. Compared to females, more males reported same-sex sexual contact (19.4 vs. 2.3 %) or same-sex romantic relationships (9.2 vs. 4.1 %). Young adults reporting same-sex behavior had higher odds of smoking, drug use, perceived stress, and more sexual partners as compared to their peers. Males who reported same-sex behavior initiated sex earlier than those males who did not report same-sex behaviors. There were no significant differences in depressive distress. Earlier sexual initiation and higher levels of substance use among Filipino young adults engaging in same-sex behavior highlight the need to address unique health issues within this population. Mixed findings for depressive distress and perceived stress indicate that further investigation is needed to explore the potential impacts of same-sex status on mental health outcomes, particularly in lower- and middle-income countries such as the Philippines. PMID:25416159

  3. Prevalence and Correlates of Sex Exchange Among a Nationally Representative Sample of Adolescents and Young Adults.

    PubMed

    Ulloa, Emilio; Salazar, Marissa; Monjaras, Lidia

    2016-07-01

    The present study examines prevalence and correlates of exchanging sex for drugs, money, food shelter, or other favors (sex exchange) among a nationally representative sample of youth and young adults. Adolescents and young adults (n = 11,620, 53% female, 47% male) from the National Longitudinal Study of Adolescent Health were used for the current sample. Participants completed in-home interviews at both waves. Results revealed that sex exchange was reported by 4.9% (n = 569) of the population in wave 2 or wave 3, and 4.6% (n = 26) of those who exchanged sex did so at both waves. More males reported exchanging sex than females (n = 332 versus n = 237). Respondents who reported child sexual abuse were more likely to exchange sex (95% CI 2.51-4.28, p < .05) than respondents who reported any other form of child abuse. Both males and females who engaged in sex exchange were at greater risk for sexually transmitted infections; however, the odds of ever exchanging sex were highest among males who ever had gonorrhea (OR = 6.2; 95% CI 3.75-10.3). Although sex exchange has been studied extensively among homeless and runaway youth, the current study reveals sex exchange also occurs in the general population. PMID:27266400

  4. A comparison of sex offenders against female and male minors.

    PubMed

    Freund, K; Watson, R; Rienzo, D

    1987-01-01

    Male sex offenders against minors were grouped according to age and sex of victims, and according to whether they had offended against one or more than one minor. Cases of incest or courtship disorder were not included in the study. Among offenders against female children, the number of one-case offenders was substantially larger than that of multicase offenders. The opposite was true of offenders against male children, and there was no significant difference between one-case and multicase offenders against female or male early adolescents. If these counts reflect corresponding prevalences within sex offenders against minors in a Western cultural setting, some inferences can be made from these comparisons. PMID:3694689

  5. Breeding Sex Ratios in Adult Leatherback Turtles (Dermochelys coriacea) May Compensate for Female-Biased Hatchling Sex Ratios

    PubMed Central

    Stewart, Kelly R.; Dutton, Peter H.

    2014-01-01

    For vertebrates with temperature-dependent sex determination, primary (or hatchling) sex ratios are often skewed, an issue of particular relevance to concerns over effects of climate change on populations. However, the ratio of breeding males to females, or the operational sex ratio (OSR), is important to understand because it has consequences for population demographics and determines the capacity of a species to persist. The OSR also affects mating behaviors and mate choice, depending on the more abundant sex. For sea turtles, hatchling and juvenile sex ratios are generally female-biased, and with warming nesting beach temperatures, there is concern that populations may become feminized. Our purpose was to evaluate the breeding sex ratio for leatherback turtles at a nesting beach in St. Croix, USVI. In 2010, we sampled nesting females and later sampled their hatchlings as they emerged from nests. Total genomic DNA was extracted and all individuals were genotyped using 6 polymorphic microsatellite markers. We genotyped 662 hatchlings from 58 females, matching 55 females conclusively to their nests. Of the 55, 42 females mated with one male each, 9 mated with 2 males each and 4 mated with at least 3 males each, for a multiple paternity rate of 23.6%. Using GERUD1.0, we reconstructed parental genotypes, identifying 47 different males and 46 females for an estimated breeding sex ratio of 1.02 males for every female. Thus we demonstrate that there are as many actively breeding males as females in this population. Concerns about female-biased adult sex ratios may be premature, and mate choice or competition may play more of a role in sea turtle reproduction than previously thought. We recommend monitoring breeding sex ratios in the future to allow the integration of this demographic parameter in population models. PMID:24505403

  6. 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

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

    PubMed

    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

  8. Myth Information and Bizarre Beliefs of Male Juvenile Sex Offenders.

    ERIC Educational Resources Information Center

    Lakey, Joyce F.

    1992-01-01

    Describes mythical beliefs, thinking errors, and faulty attitudes collected from a group of 67 male juvenile sex offenders. Addresses four major thinking errors: pretentiousness, uniqueness, failure to assume responsibility, and distorted values. Notes that therapists need this information to develop effective treatment strategies for replacing…

  9. Black Male Masculinity and Same-Sex Friendships.

    ERIC Educational Resources Information Center

    Harris, Shanette M.

    1992-01-01

    Examines how African-American alternative masculine behaviors are expressed within same-sex peer groups and friendships. It is proposed that African-American males have adopted an alternative style of masculinity to cope with social and interpersonal pressures, even though it can sometimes be dysfunctional and associated with negative…

  10. 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…

  11. Mercury elimination rates for adult northern pike Esox lucius: evidence for a sex effect

    USGS Publications Warehouse

    Madenjian, Charles P.; Blanchfield, Paul J.; Hrenchuk, Lee E.; Van Walleghem, Jillian L. A.

    2014-01-01

    We examined the effect of sex on mercury elimination in fish by monitoring isotope-enriched mercury concentrations in the muscle tissue of three adult female and three adult male northern pike Esox lucius, which had accumulated the isotope-enriched mercury via a whole-lake manipulation and were subsequently moved to a clean lake. Mercury elimination rates for female and male northern pike were estimated to be 0.00034 and 0.00073 day−1, respectively. Thus, males were capable of eliminating mercury at more than double the rate than that of females. To the best of our knowledge, our study represents the first documentation of mercury elimination rates varying between the sexes of fish. This sex difference in elimination rates should be taken into account when comparing mercury accumulation between the sexes of fish from the same population. Further, our findings should eventually lead to an improved understanding of mechanisms responsible for mercury elimination in vertebrates.

  12. Twentieth century surge of excess adult male mortality

    PubMed Central

    Beltrán-Sánchez, Hiram; Finch, Caleb E.; Crimmins, Eileen M.

    2015-01-01

    Using historical data from 1,763 birth cohorts from 1800 to 1935 in 13 developed countries, we show that what is now seen as normal—a large excess of female life expectancy in adulthood—is a demographic phenomenon that emerged among people born in the late 1800s. We show that excess adult male mortality is clearly rooted in specific age groups, 50–70, and that the sex asymmetry emerged in cohorts born after 1880 when male:female mortality ratios increased by as much as 50% from a baseline of about 1.1. Heart disease is the main condition associated with increased excess male mortality for those born after 1900. We further show that smoking-attributable deaths account for about 30% of excess male mortality at ages 50–70 for cohorts born in 1900–1935. However, after accounting for smoking, substantial excess male mortality at ages 50–70 remained, particularly from cardiovascular disease. The greater male vulnerability to cardiovascular conditions emerged with the reduction in infectious mortality and changes in health-related behaviors. PMID:26150507

  13. 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

  14. Sex hormones and adult hippocampal neurogenesis: Regulation, implications, and potential mechanisms.

    PubMed

    Mahmoud, Rand; Wainwright, Steven R; Galea, Liisa A M

    2016-04-01

    Neurogenesis within the adult hippocampus is modulated by endogenous and exogenous factors. Here, we review the role of sex hormones in the regulation of adult hippocampal neurogenesis in males and females. The review is framed around the potential functional implications of sex hormone regulation of adult hippocampal neurogenesis, with a focus on cognitive function and mood regulation, which may be related to sex differences in incidence and severity of dementia and depression. We present findings from preclinical studies of endogenous fluctuations in sex hormones relating to reproductive function and ageing, and from studies of exogenous hormone manipulations. In addition, we discuss the modulating roles of sex, age, and reproductive history on the relationship between sex hormones and neurogenesis. Because sex hormones have diverse targets in the central nervous system, we overview potential mechanisms through which sex hormones may influence hippocampal neurogenesis. Lastly, we advocate for a more systematic consideration of sex and sex hormones in studying the functional implications of adult hippocampal neurogenesis. PMID:26988999

  15. [Electrophysiological and behavioral responses of male Apamea apameoides (Draudt) (Lepidoptera: Noctuidae) to sex pheromone components].

    PubMed

    Zhang, Ai-Liang; Zhou, Zhang-Ting; Zhang, Ya-Bo; Zhou, Zhi-Feng; Shen, Zhi-Lian; Wang, Hao-Jie; Shu, Jin-Ping

    2014-10-01

    The sex pheromone gland extracts collected from calling females of Apamea apameoides (Lepidoptera: Noctuidae) were analyzed with GC-MS, the electrophysiological and behavioral responses of the male adults to serial dilutions of sex pheromone components and their synthetic blends were investigated with Y-tube olfactometer in laboratory and in bamboo forest field. The results indicated that (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol were the functional components in the sex pheromone gland extracts. Electroantennogram (EAG) recordings showed that sex pheromone gland extracts, (Z)-11-hexadecenyl acetate, (Z)-11-hexadecen-1-ol and the mixture of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol all could elicit strong EAG responses, and the average EAG values increased with the increasing concentration of the sex pheromone. The blends of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol at the ratio of 57:43 elicited a higher EAG value than each singular component did. The results of behavioral assay by Y-tube olfactometer accorded with those of EAG responses on the whole, and the mixture of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol at the ratio of 57:43 was more attractive than each component alone. In field tests with silicone rubber as pheromone dispensers (concentration = 10(4) ng · uL(-1)), the average number of male adults captured per trap by the mixture was (48.5 ± 6.7). PMID:25796914

  16. Masculinity and relationship agreements among male same-sex couples.

    PubMed

    Wheldon, Christopher W; Pathak, Elizabeth B

    2010-09-01

    Extradyadic sex is a significant source of risk for sexually transmitted infections (STIs) among men in same-sex relationships. Nonmonogamous sexual agreements are common among male same-sex couples and may serve as effective targets for risk reduction interventions; however, there is a dearth of research reporting on the social and cultural determinants of explicit nonmonogamous agreements. In this study, it was hypothesized that attitudes toward dominant cultural standards of masculinity (i.e., normative masculinity) would be associated with the types of sexual agreements negotiated among gay male couples. An Internet-based survey was used to collect data from 931 men for this analysis. Results indicated that men who reported high endorsement of normative masculinity were more likely to be in nonmonogamous relationships. Furthermore, high endorsement of normative masculinity was predictive of relationship agreements characterized as the most sexually permissive. These findings indicate that rather than simply predicting nonmonogamy in gay male couples, attitudes toward masculinity may be indirectly related to increased risk of STIs by influencing the types of sexual agreements negotiated. This is the first empirical study to emphasize the role of masculinity as an explanatory factor of same-sex relationship agreements. PMID:19626535

  17. High Fetal Estrogen Concentrations: Correlation with Increased Adult Sexual Activity and Decreased Aggression in Male Mice

    NASA Astrophysics Data System (ADS)

    Vom Saal, Frederick S.; Grant, William M.; McMullen, Carol W.; Laves, Kurt S.

    1983-06-01

    In the house mouse (Mus musculus), fetuses may develop in utero next to siblings of the same or opposite sex. The amniotic fluid of the female fetuses contains higher concentrations of estradiol than that of male fetuses. Male fetuses that developed in utero between female fetuses had higher concentrations of estradiol in their amniotic fluid than males that were located between other male fetusesw during intrauterine development. They were also more sexually active as adults, less aggressive, and had smaller seminal vesicles than males that had developed between other male fetuses in utero. These findings raise the possibility that during fetal life circulating estrogens may interact with circulating androgens both in regulating the development of sex differences between males and females and in producing variation in phenotype among males and among females.

  18. 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

  19. 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

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

    PubMed

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

    2004-11-01

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

  1. Transgenerational sex determination: the embryonic environment experienced by a male affects offspring sex ratio

    PubMed Central

    Warner, Daniel A.; Uller, Tobias; Shine, Richard

    2013-01-01

    Conditions experienced during embryonic development can have lasting effects, even carrying across generations. Most evidence for transgenerational effects comes from studies of female mammals, with much less known about egg-laying organisms or paternally-mediated effects. Here we show that offspring sex can be affected by the incubation temperature its father experiences years earlier. We incubated eggs of an Australian lizard with temperature-dependent sex determination under three thermal regimes; some eggs were given an aromatase inhibitor to produce sons at temperatures that usually produce only daughters. Offspring were raised to maturity and freely interbred within field enclosures. After incubating eggs of the subsequent generation and assigning parentage, we found that the developmental temperature experienced by a male significantly influences the sex of his future progeny. This transgenerational effect on sex ratio may reflect an epigenetic influence on paternally-inherited DNA. Clearly, sex determination in reptiles is far more complex than is currently envisaged. PMID:24048344

  2. Orthodontic treatment need in Asian adult males.

    PubMed

    Soh, Jen; Sandham, Andrew

    2004-12-01

    Orthodontic treatment in adults has gained social and professional acceptance in recent years. An assessment of orthodontic treatment need helps to identify individuals who will benefit from treatment and safeguard their interest. The purpose of this study was to assess the objective and subjective levels of orthodontic treatment need in a sample of orthodontically untreated adult Asian males. A sample of male army recruits (n = 339, age 17-22 years, Chinese = 258, Malay = 60, Indian = 21) with no history of orthodontic treatment or craniofacial anomalies participated in the study on a voluntary basis with informed consent. Impressions for study models were taken. Objective treatment need was assessed based on study model analysis using the Index of Orthodontic Treatment Need (IOTN). Questionnaires were used to assess subjective treatment need based on subjective esthetic component (EC) ratings. Fifty percentage of the sample had a definite need for orthodontic treatment (dental health component [DHC] grades 4 and 5), whereas 29.2% had a moderate need for treatment (DHC grades 3). The occlusal trait most commonly identified was dental crossbite. Malay males had the highest percentage with a definite need for treatment for both dental health and esthetic reasons in comparison with Chinese and Indian males. However, there was no difference in the level of treatment need among the ethnic groups (P > .05). No correlation between objective and subjective EC scores was found (P > .05). A high level of investigator-identified treatment need was not supported by a similar level of subject awareness among the adult sample. PMID:15673139

  3. Sex Suffers for Younger Adults After Heart Attack

    MedlinePlus

    ... 160722.html Sex Suffers for Younger Adults After Heart Attack Lack of interest a complaint of many women ... WEDNESDAY, Aug. 31, 2016 (HealthDay News) -- After a heart attack, many younger adults experience sexual difficulties -- and women ...

  4. 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…

  5. Patient-specific FDG dosimetry for adult males, adult females, and very low birth weight infants

    NASA Astrophysics Data System (ADS)

    Niven, Erin

    Fluorodeoxyglucose is the most commonly used radiopharmaceutical in Positron Emission Tomography, with applications in neurology, cardiology, and oncology. Despite its routine use worldwide, the radiation absorbed dose estimates from FDG have been based primarily on data obtained from two dogs studied in 1977 and 11 adults (most likely males) studied in 1982. In addition, the dose estimates calculated for FDG have been centered on the adult male, with little or no mention of variations in the dose estimates due to sex, age, height, weight, nationality, diet, or pathological condition. Through an extensive investigation into the Medical Internal Radiation Dose schema for calculating absorbed doses, I have developed a simple patient-specific equation; this equation incorporates the parameters necessary for alterations to the mathematical values of the human model to produce an estimate more representative of the individual under consideration. I have used this method to determine the range of absorbed doses to FDG from the collection of a large quantity of biological data obtained in adult males, adult females, and very low birth weight infants. Therefore, a more accurate quantification of the dose to humans from FDG has been completed. My results show that per unit administered activity, the absorbed dose from FDG is higher for infants compared to adults, and the dose for adult women is higher than for adult men. Given an injected activity of approximately 3.7 MBq kg-1, the doses for adult men, adult women, and full-term newborns would be on the order of 5.5, 7.1, and 2.8 mSv, respectively. These absorbed doses are comparable to the doses received from other nuclear medicine procedures.

  6. Sex-role orientation and work adaptation of male nurses.

    PubMed

    Krausz, M; Kedem, P; Tal, Z; Amir, Y

    1992-10-01

    Three competing hypotheses regarding the influence of sex-role orientation on work-stress (pressure and strain at work) and work-attraction (work centrality and satisfaction) adaptation of 154 male nurses were contrasted. The findings reveal that even in a female-dominated profession, masculine-type male nurses were, on the whole, the best adapted type while the feminine-type male nurses were the least. The androgynous-type nurses, though ranking high in pressure and strain stemming from their work, nevertheless ranked highest in work satisfaction. In contrast, the undifferentiated were not stressed nor pressured at work, but they did not enjoy their work. These analyses were repeated for 54 female nurses. Among the female nurses no significant differences were found between the four sex role orientations, indicating that the differences found among the male nurses stemmed from the special situation in which a male nurse finds himself. It is suggested that change in the nature of the nursing profession into more "masculine" tasks also may partially explain the results. PMID:1529123

  7. Multiple risks among male and transgender sex workers in Pakistan.

    PubMed

    Collumbien, Martine; Chow, Jaime; Qureshi, Ayaz Ahmed; Rabbani, Aliya; Hawkes, Sarah

    2008-01-01

    Using data from a qualitative study and a subsequent quantitative survey among 918 male and transgender sex workers (MTSW), we explore the context of multiple risks they face. We show that over one-fifth of MTSW have sex with IDU clients. Combined with high levels of risk behavior and very low levels of risk reduction and knowledge, the extent of sexual networking with men who inject drugs contributes further to the sex workers' health risks. Our findings suggest that isolated interventions with single-risk groups are unlikely to be sufficient to control the spread of the epidemic in Pakistan. We highlight the need for integrated approaches to risk reduction programs among MTSW and IDUs. PMID:19856740

  8. Estimation of sex from the upper limb measurements of Sudanese adults.

    PubMed

    Ahmed, Altayeb Abdalla

    2013-11-01

    Sex estimation is the first biological attribute needed for personal identification from mutilated and amputated limbs or body parts in medical-legal autopsies. Populations have different sizes and proportions that affect the anthropometric assessment of sex. Relatively few published works assess the accuracy of sex estimation from soft tissue measurements of upper limb parts, except for the hand and its components, but these studies involve a limited range of global populations. The current study aimed to assess the degree of sexual dimorphism in upper limb measurements and the accuracy of using these measurements for sex estimation in a contemporary adult Sudanese population. The upper arm length, ulnar length, wrist breadth, hand length, and hand breadth of 240 right-handed Sudanese subjects (120 males and 120 females) aged between 25 and 30 years were measured by international anthropometric standards. Demarking points, sexual dimorphism indices and discriminant functions were developed from 200 subjects (100 males and 100 females) who composed the study group. All variables were sexually dimorphic. The ulnar length, wrist breadth and hand breadth significantly contributed to sex estimation. Forearm dimensions showed a higher accuracy for sex estimation than hand dimensions. Cross-validated sex classification accuracy ranged between 78.5% and 89.5%. The reliability of these standards was assessed in a test sample of 20 males and 20 females, and the results showed accuracy between 77.5% and 90%. This study provides new forensic standards for sex estimation from upper limb measurements of Sudanese adults. PMID:24237816

  9. The scent of inbreeding: a male sex pheromone betrays inbred males

    PubMed Central

    van Bergen, Erik; Brakefield, Paul M.; Heuskin, Stéphanie; Zwaan, Bas J.; Nieberding, Caroline M.

    2013-01-01

    Inbreeding depression results from mating among genetically related individuals and impairs reproductive success. The decrease in male mating success is usually attributed to an impact on multiple fitness-related traits that reduce the general condition of inbred males. Here, we find that the production of the male sex pheromone is reduced significantly by inbreeding in the butterfly Bicyclus anynana. Other traits indicative of the general condition, including flight performance, are also negatively affected in male butterflies by inbreeding. Yet, we unambiguously show that only the production of male pheromones affects mating success. Thus, this pheromone signal informs females about the inbreeding status of their mating partners. We also identify the specific chemical component (hexadecanal) probably responsible for the decrease in male mating success. Our results advocate giving increased attention to olfactory communication as a major causal factor of mate-choice decisions and sexual selection. PMID:23466986

  10. Erectile Dysfunction in the Older Adult Male.

    PubMed

    Mola, Joanna R

    2015-01-01

    Erectile dysfunction (ED) in the older adult male is a significant problem affecting more than 75% of men over 70 years of age in the United States. Older men have an increased likelihood of developing ED due to chronic disease, comorbid conditions, and age-related changes. Research has demonstrated that while the prevalence and severity of ED increases with age, sexual desire often remains unchanged. This article discusses the clinical picture of ED, including relevant pathophysiology, clinical presentation, and evaluation and treatment options. PMID:26197627

  11. Male-biased sex ratio does not promote increased sperm competitiveness in the seed beetle, Callosobruchus maculatus

    PubMed Central

    McNamara, Kathryn B.; Robinson, Stephen P.; Rosa, Márta E.; Sloan, Nadia S.; van Lieshout, Emile; Simmons, Leigh W.

    2016-01-01

    Sperm competition risk and intensity can select for adaptations that increase male fertilisation success. Evolutionary responses are examined typically by generating increased strength of sexual selection via direct manipulation of female mating rates (by enforcing monandry or polyandry) or by alteration of adult sex ratios. Despite being a model species for sexual selection research, the effect of sexual selection intensity via adult sex-ratio manipulation on male investment strategies has not been investigated in the seed beetle, Callosobruchus maculatus. We imposed 32 generations of experimental evolution on 10 populations of beetles by manipulating adult sex ratio. Contrary to predictions, males evolving in male-biased populations did not increase their testes and accessory gland size. This absence of divergence in ejaculate investment was also reflected in the fact that males from male-biased populations were not more successful in either preventing females from remating, or in competing directly for fertilisations. These populations already demonstrate divergence in mating behaviour and immunity, suggesting sufficient generations have passed to allow divergence in physiological and behavioural traits. We propose several explanations for the absence of divergence in sperm competitiveness among our populations and the pitfalls of using sex ratio manipulation to assess evolutionary responses to sexual selection intensity. PMID:27306351

  12. Male-biased sex ratio does not promote increased sperm competitiveness in the seed beetle, Callosobruchus maculatus.

    PubMed

    McNamara, Kathryn B; Robinson, Stephen P; Rosa, Márta E; Sloan, Nadia S; van Lieshout, Emile; Simmons, Leigh W

    2016-01-01

    Sperm competition risk and intensity can select for adaptations that increase male fertilisation success. Evolutionary responses are examined typically by generating increased strength of sexual selection via direct manipulation of female mating rates (by enforcing monandry or polyandry) or by alteration of adult sex ratios. Despite being a model species for sexual selection research, the effect of sexual selection intensity via adult sex-ratio manipulation on male investment strategies has not been investigated in the seed beetle, Callosobruchus maculatus. We imposed 32 generations of experimental evolution on 10 populations of beetles by manipulating adult sex ratio. Contrary to predictions, males evolving in male-biased populations did not increase their testes and accessory gland size. This absence of divergence in ejaculate investment was also reflected in the fact that males from male-biased populations were not more successful in either preventing females from remating, or in competing directly for fertilisations. These populations already demonstrate divergence in mating behaviour and immunity, suggesting sufficient generations have passed to allow divergence in physiological and behavioural traits. We propose several explanations for the absence of divergence in sperm competitiveness among our populations and the pitfalls of using sex ratio manipulation to assess evolutionary responses to sexual selection intensity. PMID:27306351

  13. 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 (17

  14. 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

  15. 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

  16. Sex behaviour of male Japanese tourists in Bangkok, Thailand.

    PubMed

    Yokota, Fumihiko

    2006-01-01

    This paper explores why Japanese men engage in potentially risky commercial sexual behaviours while on holiday in Thailand. Semi-structured, in-depth interviews were conducted with 30 heterosexual male Japanese tourists, aged 19-36, who paid for sex with Thai women. Study participants were recruited at guesthouses in Bangkok. Analysis revealed eight main factors that encourage participation in commercial sex: a sense of freedom and anonymity during "time-out" spent travelling in a foreign country; a sense that there are permissive norms governing commercial sex in Thailand; the perceived sexual desirability of Thai women, a sense of economic and racial superiority relative to Thai women; a sense of loneliness or feeling in need of companionship; peer influence; the widespread availability of inexpensive sexual services in Thailand; and sexual desire or need. Findings indicate that Japanese male sexual conduct reflects individual drives while on holiday, in the context of interactions among Japanese peers, shaped by Thailand's socio-cultural environment. PMID:16641061

  17. Estimation of sex from the lower limb measurements of Sudanese adults.

    PubMed

    Ahmed, Altayeb Abdalla

    2013-06-10

    The sex estimation from mutilated and amputated limbs or body parts is one of the most vital steps in person identification in medical-legal autopsies. Sex estimation from lower limb anthropometric measurements has demonstrated a high degree of expected accuracy in a limited range of the global population. The aims of this study were to assess the degree of the sexual dimorphism in lower limb measurements and the accuracy of utilization of these measurements for estimation of sex in a contemporary adult Sudanese population. The tibial length, bimalleolar breadth, foot length, and foot breadth of 240 right-handed Sudanese Arab subjects (120 males and 120 females) aged between 25 and 30 years were measured following international anthropometric standards. Demarking points, sexual dimorphism indices and discriminant functions were developed from 200 subjects (100 males and 100 females) who comprised the study group. All variables were sexually dimorphic. The bimalleolar breadth and foot breadth significantly contributed to sex estimation. Leg dimensions showed a higher accuracy for sex estimation than foot dimensions. Cross-validated sex classification accuracy ranged between 78% and 89.5%. The reliability of these standards was assessed in a test sample of 20 males and 20 females, and the results showed accuracy between 75% and 90%. This study provides new forensic standards for sex estimation from lower limb measurements of Sudanese adults. PMID:23642728

  18. Sex-Ratio and Gender Differences in Depression in an Unselected Adult Population.

    ERIC Educational Resources Information Center

    Baumgart, E. P.; Oliver, J. M.

    1981-01-01

    Neither sex-ratio nor gender differences in depression were found in adult sample, similar to pattern found among university students. No demographic variable was correlated significantly with depression. Suggests results may be due to the elimination of face-to-face interviews, which expose males to greater negative repercussions for exhibiting…

  19. Sex education and rehabilitation with schizophrenic male outpatients.

    PubMed

    Lukoff, D; Gioia-Hasick, D; Sullivan, G; Golden, J S; Nuechterlein, K H

    1986-01-01

    Research indicates that schizophrenic patients lack intimate relationships and show a high rate of sexual dysfunction. Despite increasing awareness of the rights of handicapped persons to sexual expression, the treatment of schizophrenic patients rarely addresses their sexuality. A sex education program for recent-onset male schizophrenic patients attending an outpatient clinic was developed in response to several incidents involving patients' inappropriate sexual behaviors. To enhance our understanding of the current sexual functioning and needs of these patients, sex histories were taken. Almost all of the 16 patients interviewed were sexually active, with autoerotic activity predominating. Sixty-three percent of the patients reported orgasmic and/or erectile dysfunctions. Other studies have linked sexual dysfunction to the side effects of antipsychotic medications. The objectives of the sex education program were: to provide information; to clarify values; to overcome sexual dysfunction; and to enhance intimacy skills. The authors used role playing, modeling, group exercises, and explicit sex therapy audiovisual material to improve patients' intimacy skills. Patients participated actively and used the group to explore sexual issues. No exacerbations of symptoms were observed among patients participating in the program. PMID:3027886

  20. Hormone Disruption by PBDEs in Adult Male Sport Fish Consumers

    PubMed Central

    Turyk, Mary E.; Persky, Victoria W.; Imm, Pamela; Knobeloch, Lynda; Chatterton, Robert; Anderson, Henry A.

    2008-01-01

    Background Persistent pollutants, such as polychlorinated biphenyls (PCBs), affect endocrine function. Human exposure to polybrominated diphenyl ethers (PBDEs), which are similar in structure to PCBs, has increased recently, but health effects have not been well studied. Objectives Our goal in this study was to determine whether PBDE body burdens are related to thyroid and steroid hormone levels, thyroid antibodies, and thyroid disease in a cohort of frequent and infrequent adult male sport fish consumers. Methods We tested serum from 405 adult males for PBDE congeners, PCB congeners, testosterone, sex-hormone–binding globulin (SHBG), SHBG-bound testosterone, thyroglobulin antibodies, and the thyroid hormones thyroxine (T4), triiodothyronine (T3), thyroid-stimulating hormone (TSH), and T4-binding globulin (TBG). We collected data on demographics, fish consumption, medical diseases, and medication use. Results The median sum of PBDEs was 38 ng/g lipid. In 308 men without thyroid disease or diabetes, PBDEs were positively related to measures of T4 and reverse T3 and inversely related to total T3 and TSH. PBDEs were positively related to the percentage of T4 bound to albumin, and inversely related to the percentage of T4 bound to TBG. Associations of BDE congeners with hormones varied. BDE-47 was positively associated with testosterone levels. Participants with PBDEs over the 95th percentile were more likely to have thyroglobulin antibodies, although high PBDE exposure was not associated with thyroid disease. PBDE effects were independent of PCB exposure and sport fish consumption. Conclusions PBDE exposure, at levels comparable with those of the general U.S. population, was associated with increased thyroglobulin antibodies and increased T4 in adult males. PMID:19079713

  1. Television viewing and obesity in adult males.

    PubMed Central

    Tucker, L A; Friedman, G M

    1989-01-01

    We estimated the extent to which time spent watching television is associated with obesity and super-obesity among 6,138 employed adult males. After adjustment for age, smoking status, length of work week, measured physical fitness, and reported weekly hours of exercise, people who viewed TV more than three hours/day were twice as likely to be obese as those who viewed less than 1 hour/day. Those who viewed for 1 to 2 hours daily had a relative risk of 1.60 (1.21, 2.11). Physical fitness consistently confounded the associations between TV viewing and obesity/super-obesity, but the other control variables did not do so. PMID:2929820

  2. Childhood Predictors of Young Adult Male Crime.

    PubMed

    Ou, Suh-Ruu; Reynolds, Arthur J

    2010-08-01

    The study sample was drawn from the Chicago Longitudinal Study (CLS), an ongoing investigation of a panel of low-income minority children (93% Black) growing up in high-poverty neighborhoods in Chicago. The study sample included 733 males who were active by age 26. Adult criminal records were collected through administrative records and supplemented with self-reports. Outcome measures included incarceration, conviction, and felony conviction by age 26. Probit regression was used to analyze the data. Findings indicated that common childhood predictors were AFDC participation by child's age 3, negative home environment, maltreatment experience, trouble making behavior, and number of school moves. Unique predictors were mother unemployed by child's age 3 for incarceration or jail, four or more children in household by child's age 3 for felony conviction, and mother did not complete high school by child's age 3 and social competence for both incarceration or jail and felony conviction. Implications on crime prevention were discussed. PMID:20657803

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

    PubMed Central

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

    2013-01-01

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

  4. Testosterone and Adult Male Bone: Actions Independent of 5α-Reductase and Aromatase.

    PubMed

    Yarrow, Joshua F; Wronski, Thomas J; Borst, Stephen E

    2015-10-01

    Androgens and estrogens influence skeletal development and maintenance in males. However, the relative contributions of the circulating sex steroid hormones that originate from testicular/adrenal secretion versus those produced locally in bone via intracrine action require further elucidation. Our novel hypothesis is that testosterone exerts direct protective effects on the adult male skeleton independently of the actions of 5α-reductase or aromatase. PMID:26196865

  5. A case of sex reversal syndrome with sex-determining region (XX male).

    PubMed

    Yamamoto, M; Yokoi, K; Katsuno, S; Hibi, H; Miyake, K

    1995-12-01

    We examined a 32-year-old man with a 4-year history of infertility. The man's sex life, male hair pattern, and penis were normal, and he had no history of erection problems. Left and right testicular volumes were 2 ml and 3 ml, respectively. Semen analysis showed no sperm. The endocrine panel revealed increased serum luteinizing hormone and follicle-stimulating hormone levels, and a normal serum testosterone level. A testicular biopsy demonstrated that both Leydig cell and Sertoli cell hyperplasia were present, and that no germ cells were found in the tubules. A chromosome analysis done on the peripheral blood lymphocytes revealed a karyotype of 46, XX. We identified the sex-determining region, Y, by polymerase chain reaction using Y-specific probes in this patient. The diagnosis was XX male. PMID:8725494

  6. 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

  7. The Sex Attractant Pheromone of Male Brown Rats: Identification and Field Experiment.

    PubMed

    Takács, Stephen; Gries, Regine; Zhai, Huimin; Gries, Gerhard

    2016-05-10

    Trapping brown rats is challenging because they avoid newly placed traps in their habitat. Herein, we report the identification of the sex pheromone produced by male brown rats and its effect on trap captures of wild female brown rats. Collecting urine- and feces-soiled bedding material of laboratory-kept rats and comparing the soiled-bedding odorants of juvenile and adult males, as well as of adult males and females, we found nine compounds that were specific to, or most prevalent in, the odor profiles of sexually mature adult males. When we added a synthetic blend of six of these compounds (2-heptanone, 4-heptanone, 3-ethyl-2-heptanone, 2-octanone, 2-nonanone, 4-nonanone) to one of two paired food-baited trap boxes, these boxes attracted significantly more laboratory-strain female rats in laboratory experiments, and captured ten times more wild female rats in a field experiment than the corresponding control boxes. Our data show that the pheromone facilitates captures of wild female brown rats. PMID:27060700

  8. Changes in American Adults' Reported Same-Sex Sexual Experiences and Attitudes, 1973-2014.

    PubMed

    Twenge, Jean M; Sherman, Ryne A; Wells, Brooke E

    2016-10-01

    We examined change over time in the reported prevalence of men having sex with men and women having sex with women and acceptance of those behaviors in the nationally representative General Social Survey of U.S. adults (n's = 28,161-33,728, ages 18-96 years), 1972-2014. The number of U.S. adults who had at least one same-sex partner since age 18 doubled between the early 1990s and early 2010s (from 3.6 to 8.7 % for women and from 4.5 to 8.2 % for men). Bisexual behavior (having sex with both male and female partners) increased from 3.1 to 7.7 %, accounting for much of the rise, with little consistent change in those having sex exclusively with same-sex partners. The increase in same-sex partners was larger for women than for men, consistent with erotic plasticity theory. Attitudes toward same-sex sexual behavior also became substantially more accepting, d = .75, between the early 1970s and early 2010s. By 2014, 49 % of American adults believed that same-sex sexual activity was "not wrong at all," up from 11 % in 1973 and 13 % in 1990. Controlling for acceptance reduced, but did not eliminate, the increase in same-sex behavior over time. Mixed effects (hierarchical linear modeling) analyses separating age, time period, and cohort showed that the trends were primarily due to time period. Increases in same-sex sexual behavior were largest in the South and Midwest and among Whites, were mostly absent among Blacks, and were smaller among the religious. Overall, same-sex sexual behavior has become both more common (or at least more commonly reported) and more accepted. PMID:27251639

  9. Divorce and infidelity are associated with skewed adult sex ratios in birds.

    PubMed

    Liker, András; Freckleton, Robert P; Székely, Tamás

    2014-04-14

    Adult sex ratio (ASR) is a fundamental concept in population demography, and recent theory suggests that ASR plays a central role in social behavior, mating systems, and parental care. Unbalanced ASRs are predicted to influence pair-bond and mating behavior, since the rarer sex in the population has more potential partners to mate with than the more common sex. Here we use phylogenetic comparative analyses to test whether ASR is related to three major aspects of mating behavior: divorce, social polygamy, and pair-bond infidelity. ASR is strongly correlated with long-term pair bonds, since the divorce rate is higher in species with a female-biased sex ratio, indicating that mate change by pair members and/or breaking of pair bonds by unmated individuals is more frequent when females outnumber males. Short-term pair bonds are also associated with unbalanced ASRs: males are more commonly polygamous when females outnumber males, and conversely, females are more polygamous when males outnumber females. Furthermore, infidelity increases with male-biased ASR in socially monogamous birds, suggesting that male coercion and/or female willingness to cheat the partner are facilitated by male-biased ASR. Our results provide the first comprehensive support for the proposition that ASR influences multiple aspects of pair-bond and mating behavior in wild populations. PMID:24656831

  10. Environmental factors influencing adult sex ratio in Poecilia reticulata: laboratory experiments.

    PubMed

    McKellar, A E; Hendry, A P

    2011-10-01

    The potential causes of adult sex ratio variation in guppies Poecilia reticulata were tested in laboratory experiments that evaluated the mortality rates of male and female P. reticulata exposed to potential predators (Hart's rivulus Rivulus hartii and freshwater prawns Macrobrachium crenulatum) and to different resource levels. Poecilia reticulata mortality increased in the presence of R. hartii and M. crenulatum, and low resource levels had an effect on mortality only in the presence of M. crenulatum. Rivulus hartii preyed more often on male than on female P. reticulata, and this sex-biased predation was not simply the result of males being smaller than females. In contrast, no sex-biased mortality was attributable to M. crenulatum or low resource levels. PMID:21967582

  11. A psychosocial study of male-to-female transgendered and male hustler sex workers in São Paulo, Brazil.

    PubMed

    Prado Cortez, Fernanda Cestaro; Boer, Douglas Pieter; Baltieri, Danilo Antonio

    2011-12-01

    This study examined sociodemographic variables, personality characteristics, and alcohol and drug misuse among male sex workers in the city of Santo André, São Paulo, Brazil. A total of 45 male-to-female transgender sex workers and 41 male hustlers were evaluated in face-to-face interviews at their place of work from 2008 to 2010. A "snowball" sampling procedure was used to access this hard-to-reach population. Male-to-female transgender sex workers reported fewer conventional job opportunities, fewer school problems, and higher harm avoidance and depression levels than male hustlers. Also, transgender sex workers reported earning more money through sex work and more frequently living in hostels with peers than their counterparts. As biological male sex workers are a heterogeneous population, attempts to classify them into distinctive groups should be further carried out as a way to better understand and identify their behavior, design effective health interventions, and consequently minimize the likelihood of unintended adverse outcomes. Our study showed that gender performance can be an important variable to be considered by researchers and policy makers when working with sex workers and developing HIV/AIDS prevention and public health programs, given that transgender and male sex workers not only display distinctive behavior and physical appearance but also reveal differences on specific psychological measures, such as personality traits and depression levels. We recommend that counselors working with this population strike a balance between facilitating self-disclosure and establishing more evidence-based directive interventions. PMID:21667231

  12. Sex Differences in the Longitudinal Prediction of Adult Personality.

    ERIC Educational Resources Information Center

    Sutton-Smith, B.; Rosenberg, B. G.

    This paper deals with two sets of data-one that fails to find any long-term sex differences in adults, and another which seems to find such differences. The Berkeley Guidance Study offers longitudinal data in which no variables differentiate between the two sexes at all age levels. From these results, the authors conclude that the normal course of…

  13. Sex chromosome recombination failure, apoptosis, and fertility in male mice.

    PubMed

    Faisal, Imrul; Kauppi, Liisa

    2016-06-01

    Lack of crossing-over in meiosis can trigger an apoptotic response at metaphase I by the spindle assembly checkpoint (SAC). In contrast to females, segregation of sex chromosomes in males poses a particular challenge as recombination and chiasma formation is restricted to the pseudoautosomal region, the small region of homology between X and Y chromosomes. Existing data indicate that low levels of crossover failure in male meiosis can be tolerated without compromising fertility, while high levels of X-Y dissociation (in ≥70 % of cells) result in widespread apoptosis and subsequent infertility, demonstrated earlier, e.g., in Spo11β-only mice. Here, we explore the threshold of X-Y recombination failure frequency that is compatible with fertility. We show that in Spo11β-only(mb) mice with a mixed genetic background, in contrast to Spo11β-only mice with a C57BL/6 background, X-Y pairing fails in ~50 % of cells but this still allows for sperm production without any overt impact on fertility. We also review data on apoptosis and fertility from other achiasmate mouse models and propose that the incidence of homolog dissociation that can be tolerated in vivo without compromising male fertility lies between 50 and 70 %. PMID:26440410

  14. Male prostitutes and safe sex: different settings, different risks.

    PubMed

    de Graaf, R; Vanwesenbeeck, I; van Zessen, G; Straver, C J; Visser, J H

    1994-01-01

    Twenty-seven male prostitutes were interviewed extensively about their work and considerations relating to safe sex with clients. Important differences were found between street prostitutes and those working at home. Street-workers were more likely to be using hard drugs, to have a heterosexual preference, to have no other occupation, to have more clients, but less steady ones, and to have a more negative working attitude. Sexual techniques most often practised were manual and oral contact; however, most prostitutes also practised either insertive or receptive anal intercourse. Homosexual male prostitutes reported more receptive anal intercourse than did their heterosexual male colleagues; but no such differences were found in insertive anal intercourse. Prostitutes were most likely to have had anal intercourse with steady clients, with clients whom they trusted regarding condom use, or with clients they felt sexually attracted to; and also when in dire need of drugs. Of those who had practised anal intercourse in the previous year, a minority had not consistently used condoms. The same factors that encourage anal intercourse also appear conducive to unprotected intercourse. PMID:7948084

  15. Anatomic autoandrophilia in an adult male.

    PubMed

    Lawrence, Anne A

    2009-12-01

    Some men are sexually aroused by impersonating the individuals to whom they are sexually attracted, or by permanently changing their bodies to become facsimiles of such individuals. Blanchard (J Sex Marital Ther 17:235-251, 1991) suggested that these paraphilic sexual interests, along with fetishism, represented erotic target location errors, i.e., developmental errors in locating erotic targets in the environment. Because the desire to impersonate or become a facsimile of the kind of person to whom one is attracted can have significant implications for identity, Freund and Blanchard (Br J Psychiatry 162:558-563, 1993) coined the term erotic target identity inversion to describe this type of erotic target location error. The best-known examples of erotic target identity inversions occur in men who are sexually attracted to women and who are also sexually aroused by the idea of impersonating or becoming women; these paraphilic interests manifest as transvestic fetishism and as one type of male-to-female transsexualism. Analogous erotic target identity inversions have been described in men who are sexually attracted to children and to female amputees. In theory, erotic target identity inversions should also occur in men who are sexually attracted to men. There have been no unambiguous descriptions, however, of men who are sexually attracted to men and also sexually aroused by the idea of changing their bodies to become more sexually attractive men. This report describes such a man, whose paraphilic interest would appropriately be called anatomic autoandrophilia. The demonstration that anatomic autoandrophilia exists in men is consistent with the theory that erotic target location errors constitute an independent paraphilic dimension. PMID:19093196

  16. Endogenous brain erythropoietin is a potent sex-specific respiratory stimulant in adult and newborn mice.

    PubMed

    Ballot, Orlane; Joseph, Vincent; Soliz, Jorge

    2015-06-01

    We tested the hypothesis that endogenous brain Epo is a respiratory stimulant. Adult (3 mo) and newborn (10 days) male and female mice received an intracisternal (cisterna magna) injection of soluble Epo receptor (sEpoR; competes with EpoR to bind Epo; 50 μg/ml) or vehicle (0.1% BSA in PBS). Twenty-four hours after injection, we used whole body plethysmography to record minute ventilation (V̇e) tidal volume (VT), respiratory frequency (fR), O2 consumption (V̇o2), and CO2 production (V̇co2) under normoxia and progressive exposure to hypoxia (12-10-6% O2; 10 min each). In adult male and female mice sEpoR decreased normoxic V̇e (-25%), due to a decrease of VT in males and fR in females. Moreover, sEpoR injection decreased the ventilatory response to 12% O2, assessed as V̇e/V̇o2 or V̇e/V̇co2, in male but not in female mice. In newborn male and female mice sEpoR decreased V̇e (-37% in males, -59% in females) and VT (-38% in males, -47% in females) in normoxia and fR in females. During hypoxia, sEpoR decreased V̇e/V̇o2 and V̇e/V̇co2 in mice of both sexes. Upon extreme hypoxia (6% O2), the newborn mice treated with sEpoR showed respiratory depression, signs of asphyxia (gasping) and a high mortality rate in males and females. We concluded that endogenous brain Epo is a potent respiratory stimulant under normoxia and hypoxia in adult and newborn mice. Because sex-specific effects are different in newborn male and female, sex steroids secreted at different ages mice appear to modulate the effects of Epo on respiratory regulation in normoxia and in response to hypoxia. PMID:25792712

  17. Sex Education for Deaf-Blind Youths and Adults.

    ERIC Educational Resources Information Center

    Ingraham, Cynthia L.; Vernon, McCay; Clemente, Brenda; Olney, Linda

    2000-01-01

    This article describes a model sex education program developed for youths and adults who are deafblind by the Helen Keller National Center for Deaf-Blind Youths and Adults. In addition, it also discusses major related issues and presents general recommendations and a resource for further information. (Contains 11 references.) (Author/CR)

  18. OXIDATIVE STRESS CONTRIBUTES TO SEX DIFFERENCES IN BLOOD PRESSURE IN ADULT GROWTH RESTRICTED OFFSPRING

    PubMed Central

    Ojeda, Norma B.; Hennington, Bettye Sue; Williamson, Danielle T.; Hill, Melanie L.; Betson, Nicole E.E.; Sartori-Valinotti, Julio C.; Reckelhoff, Jane F.; Royals, Thomas P.; Alexander, Barbara T.

    2013-01-01

    Numerous experimental studies suggest that oxidative stress contributes to the pathophysiology of hypertension and importantly, that oxidative stress plays a more definitive role in mediating hypertension in males than in females. Intrauterine growth-restriction induced by reduced uterine perfusion initiated at day 14 of gestation in the rat programs hypertension in adult male growth-restricted offspring; yet, female growth-restricted offspring are normotensive. The mechanisms mediating sex differences in blood pressure in adult growth-restricted offspring are not clear. Thus, this study tested the hypothesis that sex specific differences in renal oxidative stress contribute to the regulation of blood pressure in adult growth-restricted offspring. A significant increase in blood pressure measured by telemetry in male growth-restricted offspring (P<0.05) was associated with a marked increase in renal markers of oxidative stress (P<0.05). Chronic treatment with the antioxidant tempol had no effect on blood pressure in male control offspring, but it normalized blood pressure (P<0.05) and renal markers of oxidative stress (P<0.05) in male growth-restricted relative to male control. Renal markers of oxidative stress were not elevated in female growth-restricted offspring; however, renal activity of the antioxidant catalase was significantly elevated relative to female control (P<0.05). Chronic treatment with tempol did not significantly alter oxidative stress or blood pressure measured by telemetry in female offspring. Thus, these data suggest that sex differences in renal oxidative stress and antioxidant activity are present in adult growth-restricted offspring, and that oxidative stress may play a more important role in modulating blood pressure in male, but not female growth-restricted offspring. PMID:22585945

  19. Sex differences in spatial navigation and perception in human adolescents and emerging adults

    PubMed Central

    Sneider, Jennifer Tropp; Hamilton, Derek A.; Cohen-Gilbert, Julia E.; Crowley, David J.; Rosso, Isabelle M.; Silveri, Marisa M.

    2014-01-01

    Males typically outperform females on spatial tasks, beginning early in life and continuing into adulthood. This study aimed to characterize age and sex differences in human spatial ability using a virtual Water Maze Task (vWMT), which is based on the classic Morris water maze spatial navigation task used in rodents. Performance on the vWMT and on a task assessing visuospatial perception, Mental Rotations Test (MRT), was examined in 33 adolescents and 39 emerging adults. For the vWMT, significant effects of age and sex were observed for path length in the target region (narrower spatial sampling), and heading error, with emerging adults performing better than adolescents, and an overall male advantage. For the MRT, males scored higher than females, but only in emerging adulthood. Overall, sex differences in visuospatial perception (MRT) emerge differently from those observed on a classic navigation task, with age and sex-specific superior vWMT performance likely related to the use of more efficient strategies. Importantly, these results extend the developmental timeline of spatial ability characterization to include adolescent males and females performing a virtual version of the classic vWMT. PMID:25464337

  20. Sex differences in spatial navigation and perception in human adolescents and emerging adults.

    PubMed

    Sneider, Jennifer T; Hamilton, Derek A; Cohen-Gilbert, Julia E; Crowley, David J; Rosso, Isabelle M; Silveri, Marisa M

    2015-02-01

    Males typically outperform females on spatial tasks, beginning early in life and continuing into adulthood. This study aimed to characterize age and sex differences in human spatial ability using a virtual Water Maze Task (vWMT), which is based on the classic Morris water maze spatial navigation task used in rodents. Performance on the vWMT and on a task assessing visuospatial perception, Mental Rotations Test (MRT), was examined in 33 adolescents and 39 emerging adults. For the vWMT, significant effects of age and sex were observed for path length in the target region (narrower spatial sampling), and heading error, with emerging adults performing better than adolescents, and an overall male advantage. For the MRT, males scored higher than females, but only in emerging adulthood. Overall, sex differences in visuospatial perception (MRT) emerge differently from those observed on a classic navigation task, with age and sex-specific superior vWMT performance likely related to the use of more efficient strategies. Importantly, these results extend the developmental timeline of spatial ability characterization to include adolescent males and females performing a virtual version of the classic vWMT. PMID:25464337

  1. Prevalence and Correlates of Non-Disclosure of HIV Serostatus to Sex partners among HIV-Infected Female Sex Workers and HIV-infected Male Clients of Female Sex Workers in India

    PubMed Central

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

    2013-01-01

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

  2. Recognition and Sex Categorization of Adults' and Children's Faces: Examining Performance in the Absence of Sex-Stereotyped Cues.

    ERIC Educational Resources Information Center

    Wild, Heather A.; Barett, Susan E.; Spence, Melanie J.; O'Toole, Alice J.; Cheng, Yi D.; Brooke, Jessica

    2000-01-01

    Investigated 7-year-olds', 9-year-olds', and adults' ability to classify children's and adults' faces by sex using only biological based internal facial structure. Found that participants categorized adult faces by sex at accuracy levels varying from just above chance (7-year-olds) to nearly perfect (adults). All groups were less accurate for…

  3. Sex and laterality differences in medial amygdala neurons and astrocytes of adult mice.

    PubMed

    Pfau, Daniel R; Hobbs, Nicholas J; Breedlove, S Marc; Jordan, Cynthia L

    2016-08-15

    The posterodorsal aspect of the medial amygdala (MePD) in rats is sexually dimorphic, being larger and containing more and larger neurons in males than in females. It is also highly lateralized, with the right MePD larger than the left in both sexes, but with the smaller left MePD actually containing more and larger neurons than the larger right. Astrocytes are also strikingly sexually differentiated, with male-biased numbers and lateralized favoring the right in the rat MePD. However, comparable information is scant for mice where genetic tools offer greater experimental power. Hence, we examined the MePD from adult male and female C57Bl/6(J) mice. We now report that the MePD is larger in males than in females, with the MePD in males containing more astrocytes and neurons than in females. However, we did not find sex differences in astrocyte complexity or overall glial number nor effects of laterality in either measure. While the mouse MePD is generally less lateralized than in rats, we did find that the sex difference in astrocyte number is only on the right because of a significant lateralization in females, with significantly fewer astrocytes on the right than the left but only in females. A sex difference in neuronal soma size favoring males was also evident, but only on the left. Sex differences in the number of neurons and astrocytes common to both rodent species may represent core morphological features that critically underlie the expression of sex-specific behaviors that depend on the MePD. J. Comp. Neurol. 524:2492-2502, 2016. © 2016 Wiley Periodicals, Inc. PMID:26780286

  4. 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

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

    ERIC Educational Resources Information Center

    Freeman, Naomi J.; Sandler, Jeffrey C.

    2008-01-01

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

  6. 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)

  7. 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…

  8. An Investigation of Sex-Related Slang Vocabulary and Sex-Role Orientation Among Male and Female University Students

    ERIC Educational Resources Information Center

    Kutner, Nancy G.; Brogan, Donna

    1974-01-01

    Undergraduate males, undergraduate females, and graduate student nurses (female) were asked to list all the slang expressions they knew for 17 sex-related stimulus words. Males listed a significantly larger total number of slang expressions than either female group. (Author)

  9. 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 3β-hydroxysteroid dehydrogenase (3β-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

  10. Does the timing of attainment of maturity influence sexual size dimorphism and adult sex ratio in turtles?

    USGS Publications Warehouse

    Lovich, Jeffrey E.; Gibbons, J. Whitfield; Agha, Mickey

    2014-01-01

    The attainment of sexual maturity has been shown to affect measures of sexual size dimorphism (SSD) and adult sex ratios in several groups of vertebrates. Using data for turtles, we tested the model that sex ratios are expected to be male-biased when females are larger than males and female-biased when males are larger than females because of the relationship of each with the attainment of maturity. Our model is based on the premise that the earlier-maturing sex remains smaller, on average throughout life, and predominates numerically unless the sexes are strongly affected by differential mortality, differential emigration, and immigration, or biased primary sex ratios. Based on data for 24 species in seven families, SSD and sex ratios were significantly negatively correlated for most analyses, even after the effect of phylogenetic bias was removed. The analyses provide support for the model that SSD and adult sex ratios are correlated in turtles as a result of simultaneous correlation of each with sexual differences in attainment of maturity (bimaturism). Environmental sex determination provides a possible mechanism for the phenomenon in turtles and some other organisms.

  11. Influence of host fruit and conspecifics on the release of the sex pheromone By Toxotrypana curvicauda males (Diptera: Tephritidae).

    PubMed

    Robledo, Norma; Arzuffi, René

    2012-04-01

    The release of tephritid sex pheromones depends significantly on the age of the male, the social context (presence of conspecifics) and chemical context (host volatiles). In this study, the influence of host fruit and conspecific (males and females) on the emission of the pheromonal compound 2-methyl-6-vinylpyrazine (2,6 mvp) by Toxotrypana curvicauda (Gerstaecker) males was investigated under laboratory conditions. Males were divided into one control group (nonexposed to treatment) and five experimental groups were placed 1 hr before volatile collection with: 1) host fruit (unripe papaya), 2) two females, 3) two males, 4) host fruit plus two females, and 5) host fruit plus two males. The volatiles were sampled by means of solid phase microextraction and analyzed with gas chromatography-mass spectrometry, with a focus on 2,6 mvp. Males emitted volatiles from the first day after adult emergence. The maximum peak and the temporal pattern of 2,6 mvp release were modified by the presence of host fruit and conspecific males or females. On day 5, males in the presence of fruit maintained a constant release of 2,6 mvp while the presence of conspecific caused a decrease of pheromone release. The release of 2,6 mvp was increased significantly in males exposed to both types of stimuli simultaneously. The stimuli (fruit and conspecifics) modified the release of 2,6 mvp, however the effect depended on male age. PMID:22507013

  12. 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

    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.

  13. Sexual Behaviors and AIDS Concerns among Young Adult Heterosexual Males.

    ERIC Educational Resources Information Center

    Pomerantz, Sherry C.; Vergare, Michael J.

    As the human immunodeficiency virus spreads beyond homosexuals and intravenous drug users into the heterosexual community, there is heightened interest in the sexual behavior of sexually active young adults. There is little information on young adult black males, who may be at increased risk, since blacks in this country are contracting Acquired…

  14. Sex Differences in the Manifestation of ADHD in Emerging Adults

    ERIC Educational Resources Information Center

    Fedele, David A.; Lefler, Elizabeth K.; Hartung, Cynthia M.; Canu, Will H.

    2012-01-01

    Objective: Given the mixed literature in the area, the aim of the current study was to determine whether sex differences exist in inattention, hyperactivity, and impairment in college adults with ADHD. Method: Individuals from three universities were recruited for the study. Participants with (n = 164) and without ADHD (n = 710) completed on-line…

  15. Student Sex: More or Less Risky than Other Young Adults?

    ERIC Educational Resources Information Center

    Burke, Lorraine; Nic Gabhainn, Saoirse; Young, Honor

    2015-01-01

    Sexually active young adults are at an increased risk of acquiring sexually transmitted infections (STIs) or experiencing an unplanned pregnancy. Sexual behaviours such as inconsistent condom use, multiple partners and casual sex are known risk factors for negative sexual health outcomes. Sexually active higher education students are classified as…

  16. Sex chromosomes and male ornaments: a comparative evaluation in ray-finned fishes

    PubMed Central

    Mank, Judith E; Hall, David W; Kirkpatrick, Mark; Avise, John C

    2005-01-01

    Theory predicts that the mechanism of genetic sex determination can substantially influence the evolution of sexually selected traits. For example, female heterogamety (ZZ/ZW) can favour the evolution of extreme male traits under Fisher's runaway model of sexual selection. We empirically test whether the genetic system of sex determination has played a role in the evolution of exaggerated male ornaments in actinopterygiian fishes, a clade in which both female-heterogametic and male-heterogametic systems of sex determination have evolved multiple times. Using comparative methods both uncorrected and corrected for phylogenetic non-independence, we detected no significant correlation between sex-chromosome systems and sexually selected traits in males. Results suggest that sex-determination mechanism is at best a relatively minor factor affecting the outcomes of sexual selection in ray-finned fishes. PMID:16555792

  17. Double-strand break repair on sex chromosomes: challenges during male meiotic prophase

    PubMed Central

    Lu, Lin-Yu; Yu, Xiaochun

    2015-01-01

    During meiotic prophase, DNA double-strand break (DSB) repair-mediated homologous recombination (HR) occurs for exchange of genetic information between homologous chromosomes. Unlike autosomes or female sex chromosomes, human male sex chromosomes X and Y share little homology. Although DSBs are generated throughout male sex chromosomes, homologous recombination does not occur for most regions and DSB repair process is significantly prolonged. As a result, male sex chromosomes are coated with many DNA damage response proteins and form a unique chromatin structure known as the XY body. Interestingly, associated with the prolonged DSB repair, transcription is repressed in the XY body but not in autosomes, a phenomenon known as meiotic sex chromosome inactivation (MSCI), which is critical for male meiosis. Here using mice as model organisms, we briefly summarize recent progress on DSB repair in meiotic prophase and focus on the mechanism and function of DNA damage response in the XY body. PMID:25565522

  18. 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

  19. 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

  20. Acute effects of sex-specific sex hormones on heat shock proteins in fast muscle of male and female rats.

    PubMed

    Romani, William A; Russ, David W

    2013-10-01

    Heat shock protein (HSP) expression and sex hormone levels have been shown to influence several aspects of skeletal muscle physiology (e.g., hypertrophy, resistance to oxidative stress), suggesting that sex hormone levels can effect HSP expression. This study evaluated the effects of differing levels of sex-specific sex hormones (i.e., testosterone in males and estrogen in females) on the expression of 4: HSP70, HSC70, HSP25, and αB-crystallin in the quadriceps muscles of male and female rats. Animals were assigned to 1 of 3 groups (n = 5 M and F/group). The first group (Ctl) consisted of typically cage-housed animals that served as controls. The second group (H) was gonadectomized and received either testosterone (males) or estradiol (females) via injection for 12 consecutive days. The third group (Gx) was gonadectomized and injected as above, but with vehicle only, rather than hormones. Significant sex by condition interactions (P < 0.05 by two-way MANOVA) were found for all 4 proteins studied, except for HSP70, which exhibited a significant effect of condition only. The expression of all HSPs was greater (1.9-2.5-fold) in males vs. females in the Ctl group, except for HSP70, which was no different. Generally, gonadectomy appeared to have greater effects in males than females, but administration of the exogenous sex hormones tended to produce more robust relative changes in females than males. There were no differences in myosin composition in any of the groups, suggesting that changes in fiber type were not a factor in the differential protein expression. These data may have implications for sex-related differences in muscular responses to exercise, disuse, and injury. PMID:23821238

  1. “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

  2. Stable isotope evidence of meat eating and hunting specialization in adult male chimpanzees

    PubMed Central

    Fahy, Geraldine E.; Richards, Michael; Riedel, Julia; Hublin, Jean-Jacques; Boesch, Christophe

    2013-01-01

    Observations of hunting and meat eating in our closest living relatives, chimpanzees (Pan troglodytes), suggest that among primates, regular inclusion of meat in the diet is not a characteristic unique to Homo. Wild chimpanzees are known to consume vertebrate meat, but its actual dietary contribution is, depending on the study population, often either unknown or minimal. Constraints on continual direct observation throughout the entire hunting season mean that behavioral observations are limited in their ability to accurately quantify meat consumption. Here we present direct stable isotope evidence supporting behavioral observations of frequent meat eating among wild adult male chimpanzees (Pan troglodytes verus) in Taï National Park, Côte d’Ivoire. Meat eating among some of the male chimpanzees is significant enough to result in a marked isotope signal detectable on a short-term basis in their hair keratin and long-term in their bone collagen. Although both adult males and females and juveniles derive their dietary protein largely from daily fruit and seasonal nut consumption, our data indicate that some adult males also derive a large amount of dietary protein from hunted meat. Our results reinforce behavioral observations of male-dominated hunting and meat eating in adult Taï chimpanzees, suggesting that sex differences in food acquisition and consumption may have persisted throughout hominin evolution, rather than being a recent development in the human lineage. PMID:23530185

  3. 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

  4. Androgen action during male sex differentiation includes suppression of cranial suspensory ligament development.

    PubMed

    Emmen, J M; McLuskey, A; Grootegoed, J A; Brinkmann, A O

    1998-05-01

    The cranial suspensory ligament is located on the border of the cranial (mesonephric) mesentery in adult female mammals, which runs between the cranial pole of the internal genitalia and the dorsal abdominal wall. Absence of the cranial suspensory ligament in male mammals depends upon exposure of its primordium to fetal testicular androgens and is a prerequisite for testis descent. Female rats were exposed to 5alpha-dihydrotestosterone propionate at different stages of genital development, and cranial suspensory ligament development was studied in neonatal and in adult animals. Androgens suppressed cranial suspensory ligament development when exposure started during the early stages of genital development, until day 19 postconception (pc). Androgen receptor expression was immunohistochemically detected in the cranial mesentery of both sexes from day 16 pc onwards. A decrease of androgen receptor expression in female fetuses from day 18 pc onwards coincided with the appearance of a differentiated cranial suspensory ligament, as evidenced by the expression of two cell differentiation markers: alpha-smooth muscle (alpha-SM) actin and desmin. alpha-SM actin was located on the outer border of the cranial mesentery of both sexes at day 17 pc, and expression increased only in female fetuses. On day 19 pc, desmin expression was also detectable in the a-SM actin-positive cells. Proliferation and apoptosis indices of cells in the cranial mesentery, as analysed by 5'-bromodeoxyuridine incorporation and by detection of DNA strand breaks (TUNEL method) respectively, did not show any difference between the sexes, neither on day 17 nor on day 18 pc. Since primordial cells of the cranial suspensory ligament highly express the androgen receptor during the period of gestation when androgens can suppress cranial suspensory development, altered morphogenesis of these cells may be a direct consequence of androgen action. PMID:9647559

  5. 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

  6. 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

  7. 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

  8. 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)

  9. 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

  10. Sexual Abuse History among Adult Sex Offenders and Non-Sex Offenders: A Meta-Analysis

    ERIC Educational Resources Information Center

    Jespersen, Ashley F.; Lalumiere, Martin L.; Seto, Michael C.

    2009-01-01

    Objective: The sexually abused-sexual abuser hypothesis states there is a specific relationship between sexual abuse history and sexual offending, such that individuals who experience sexual abuse are significantly more likely to later engage in sexual offenses. Therefore, samples of adult sex offenders should contain a disproportionate number of…

  11. 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

  12. Neuropsychological Sex Differences Associated with Age of Initiated Use Among Young Adult Cannabis Users

    PubMed Central

    Crane, Natania A.; Schuster, Randi Melissa; Mermelstein, Robin J.; Gonzalez, Raul

    2015-01-01

    Introduction Earlier initiation of cannabis use is associated with poorer neuropsychological functioning across several domains. Given well-documented sex differences in neuromaturation during adolescence, initiation of cannabis use during this time may affect neuropsychological functioning differently for males and females. Method In the current study, we examined sex differences in the relationship between age of initiated cannabis use and neuropsychological performance after controlling for amount of lifetime cannabis use in 44 male and 25 female young adult cannabis users. Results We found that an earlier age of initiated use was related to poorer episodic memory, especially immediate recall, in females, but not in males. On the other hand, we found that, surprisingly, an earlier age of initiated use was associated with better decision-making overall. However, exploratory analyses found sex-specific factors associated with decision-making and age of initiated use, specifically that ADHD symptoms in females may drive the relationship between an earlier age of initiated use and better decision-making. Further, an earlier age of initiated use was associated with less education, a lower IQ, and fewer years of mother’s education for females, but more lifetime cannabis use for males. Conclusions Taken together, our findings suggest there are sex-differences in the associations between age of initiated cannabis use and neuropsychological functioning. The current study provides preliminary evidence that males and females may have different neuropsychological vulnerabilities that place them at risk for initiating cannabis use and continued cannabis use, highlighting the importance of examining the impact of cannabis on neuropsychological functioning separately for males and females. PMID:25832823

  13. 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

  14. Sex recognition and mate choice by male western toads, Bufo boreas.

    PubMed

    Marco; Kiesecker; Chivers; Blaustein

    1998-06-01

    In field-based choice experiments, we examined sex recognition and mate choice in male western toads, Bufo boreas. When given a simultaneous choice between a male and a female of equal size, males did not discriminate between the sexes and attempted to amplex a male or a female with equal frequency. When a test male clasped a stimulus male, the stimulus male uttered a release call that caused the test male to release the stimulus male. Male-male amplexus never lasted more than 3 s, but male-female amplexus was tenacious and prolonged. Furthermore, males discriminated between gravid females that differed in body size, choosing larger gravid females over smaller ones, but they did not discriminate between gravid females or non-gravid females of equal size. In choice tests that excluded chemical cues, males jumped more frequently towards large females than small ones. Given that females are significantly larger than males, selecting larger individuals as potential mates increases the probability that males amplex with a female. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour. PMID:9642006

  15. The female mid-life sex change applicant: a comparison with younger female transsexuals and older male sex change applicants.

    PubMed

    Roback, H B; Lothstein, L M

    1986-10-01

    This paper reports on a survey approach to the study of the aging (40 years of age and older) female requesting sex reassignment surgery (SRS). A profile of 13 cases presenting at a cross-section of gender identity clinics in North America is presented. The mid-life SRS applicant is also compared on selected characteristics with a younger female transsexual group and with the aging male sex change applicant. Findings suggest that the mid-life female SRS applicant is closely akin to the aging, conflicted homosexual, whereas the mid-life male SRS applicant appears more closely associated with the aging transvestite. PMID:3789904

  16. Dedifferentiated liposarcoma of the adult male breast

    PubMed Central

    Raj, Sean D.; Rogers, Samuel; del Junco, Gerard W.; Sepulveda, Karla

    2015-01-01

    A 66-year-old male presented with a right breast mass, enlarging insidiously over a one-year period after trauma to the site. After the findings were attributed to glandular injury and hematoma, the patient eventually underwent mammographic and ultrasonographic evaluation that demonstrated masses in the breast and the axilla. A subsequent ultrasound-guided biopsy of the breast mass yielded a diagnosis of fibromatosis. However, the imaging features were suggestive of malignancy. Surgical resection was performed and revealed dedifferentiated liposarcoma—a neoplasm with components of well- and poorly differentiated liposarcoma as well as nonlipomatous sarcoma. This tumor type is primarily described in the retroperitoneum and limbs and is especially rare in the breast. We report an unusual case of multifocal primary dedifferentiated liposarcoma involving the breast in a man. PMID:27186240

  17. Sex- and Gonad-Affecting Scent Compounds and 3 Male Pheromones in the Rat

    PubMed Central

    Sun, Lixing; Zhang, Jin-Hua; Feng, Zhi-Yong

    2008-01-01

    This study was aimed at identifying sex pheromones of the rat (Rattus norvegicus). We characterized the volatiles and semivolatiles of rat preputial gland and voided urine by using gas chromatography–mass spectrometry (GC–MS) and quantified them by their GC areas (abundances) and percentage of GC areas (relative abundances). Although all the compounds other than 4-heptanone and phenol detected were shared by males and females, the quantities for some of these sex-common compounds exhibited sexual dimorphism and decreased with gonadectomy. Thus, these compounds might be sex pheromones. Among them, squalene from preputial glands and 2-heptanone and 4-ethyl phenol from urine were 3 major compounds. They were richer in males and could be suppressed by castration. Adding any of the 3 compounds (at a concentration higher than its physiological level in male urine) to castrated male urine (CMU) increased the attractiveness of CMU to sex-naive females. Adding the 3 together (at the levels in normal male urine) to CMU significantly increased the attractiveness of CMU to females. However, such combination did not fully restore females' preference for urine from intact males, suggesting that some other trace compounds such as 4-heptanone and phenol might also play some roles in sex attractiveness. Thus, squalene, 2-heptanone, and 4-ethyl phenol were indeed male pheromone molecules in rats. Our study also indicates that E,E-β-farnesene and E-α-farnesene, both richer in females than males, might be putative female pheromones. PMID:18515819

  18. Sex- and gonad-affecting scent compounds and 3 male pheromones in the rat.

    PubMed

    Zhang, Jian-Xu; Sun, Lixing; Zhang, Jin-Hua; Feng, Zhi-Yong

    2008-09-01

    This study was aimed at identifying sex pheromones of the rat (Rattus norvegicus). We characterized the volatiles and semivolatiles of rat preputial gland and voided urine by using gas chromatography-mass spectrometry (GC-MS) and quantified them by their GC areas (abundances) and percentage of GC areas (relative abundances). Although all the compounds other than 4-heptanone and phenol detected were shared by males and females, the quantities for some of these sex-common compounds exhibited sexual dimorphism and decreased with gonadectomy. Thus, these compounds might be sex pheromones. Among them, squalene from preputial glands and 2-heptanone and 4-ethyl phenol from urine were 3 major compounds. They were richer in males and could be suppressed by castration. Adding any of the 3 compounds (at a concentration higher than its physiological level in male urine) to castrated male urine (CMU) increased the attractiveness of CMU to sex-naive females. Adding the 3 together (at the levels in normal male urine) to CMU significantly increased the attractiveness of CMU to females. However, such combination did not fully restore females' preference for urine from intact males, suggesting that some other trace compounds such as 4-heptanone and phenol might also play some roles in sex attractiveness. Thus, squalene, 2-heptanone, and 4-ethyl phenol were indeed male pheromone molecules in rats. Our study also indicates that E,E-beta-farnesene and E-alpha-farnesene, both richer in females than males, might be putative female pheromones. PMID:18515819

  19. Core groups and the transmission of HIV: learning from male sex workers.

    PubMed

    Parker, Melissa

    2006-01-01

    A growing and substantial body of research suggests that female sex workers play a disproportionately large role in the transmission of HIV in many parts of the world, and they are often referred to as core groups by epidemiologists, mathematical modellers, clinicians and policymakers. Male sex workers, by contrast, have received little attention and it is not known whether it is helpful to conceptualize them as a core group. This paper draws upon ethnographic research documenting social and sexual networks in London and looks at the position of five male sex workers within a network comprising 193 men and seven women (as well as 1378 anonymous sexual contacts and 780 commercial contacts). In so doing, it suggests that there is no evidence to show that male sex workers are more or less likely to acquire or transmit HIV in the course of commercial sex compared with other types of sexual relationships. In addition, men engaging in non-commercial sex all reported having unprotected sex in a variety of contexts and relationships and there is no evidence to suggest that men who are not sex workers play less of a role in the transmission of HIV. In short, these data suggest that it would be inappropriate to conceptualize male sex workers as a core group. This is not to suggest that public policy should continue to overlook male sex workers. New and inventive approaches are required to reach out to a vulnerable but diverse group of men, selling sex for a variety of reasons; even if these men are no more vulnerable to acquiring and/or transmitting HIV than other men and women that form part of their network. PMID:16321168

  20. 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.

  1. 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

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

    PubMed

    Katsulis, Yasmina; Durfee, Alesha

    2012-01-01

    We investigated prevalence and correlates of sexual risk behaviours among male and female sex workers in Tijuana, Mexico, the busiest border crossing area on the US - Mexico border, analysing survey data from a purposive, cross-sectional sample of male and female sex workers who worked in a range of indoor and outdoor settings. Logistic regression was used to determine factors that were associated with sexual risk-taking, defined as failing to use a condom with last client. In bivariate regression models, gender, work setting (e.g., indoor vs. outdoor), poverty, engaging in survival sex, marital status and perceived drug addiction were correlated with sexual risk. When controlling for work location, housing insecurity, poverty, survival sex, marital status and perceived drug addiction, male sex workers were still 10 times more likely than female sex workers (FSW) to engage in sex without a condom during their last encounter with a client. And, although FSW were significantly more likely than males to have used a condom with a client, they were significantly less likely than males to have used a condom with their regular partner. Future research should further examine how gender shapes sexual risk activities in both commercial and non-commercial relationships. PMID:22304493

  3. Queering Sex Education: Young Adult Literature with LGBT Content as Complementary Sources of Sex and Sexuality Education

    ERIC Educational Resources Information Center

    Bittner, Robert

    2012-01-01

    This article explores the nature of young adult texts as complementary sources of informal queer sex and sexuality education, along with a close reading of a sample of this young adult (YA) literature. LGBT teens are often left out of discussions in sex education classrooms in the United States because of discriminatory curricula, ignorance on the…

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

    PubMed Central

    2012-01-01

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

  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. Differences in Gay Male Couples' Use of Drugs and Alcohol With Sex by Relationship HIV Status.

    PubMed

    Mitchell, Jason W

    2016-07-01

    Prior studies with men who have sex with men have documented a strong association between substance use with sex and risk for acquisition of HIV. However, few studies have been conducted about gay male couples' use of substances with sex, despite the fact that between one third and two thirds of men who have sex with men acquire HIV from their relationship partners. The present study sought to (1) describe whether one or both partners in the male couple uses substances with sex-by substance type-within and/or outside of their relationship, and (2) assess whether differences exist in those who use substances with sex within and outside the relationship by the couples' HIV status. Dyadic data for this analysis were collected in the United States from a nation-wide cross-sectional Internet study about male couples' relationships and behaviors. Couple-level descriptive and comparative analyses were employed with 361 male couples. Except for alcohol, most couples did not use substances with sex. Of those who did, rates of who used it with sex and substance type within the relationship varied; most couples only had one partner who used substances with sex outside the relationship. Significantly higher proportions of concordantly HIV-negative and HIV-positive couples had both partners who used substances (all types) with sex within their relationship over discordant couples. Most couples had one partner who used outside the relationship; only marijuana and erectile dysfunction medication use with sex significantly differed by couples' HIV status. Findings indicate the need to conduct additional research for prevention development. PMID:25424504

  7. Sex differences in the timing of identification among children and adults with autism spectrum disorders.

    PubMed

    Begeer, Sander; Mandell, David; Wijnker-Holmes, Bernadette; Venderbosch, Stance; Rem, Dorien; Stekelenburg, Fred; Koot, Hans M

    2013-05-01

    To examine differences by sex in the timing of identification of individuals with autism spectrum disorders (ASD), survey data were collected in the Netherlands from 2,275 males and females with autistic disorder, Asperger's syndrome and PDD-NOS. Among participants < 18 years of age, females with Asperger's syndrome were identified later than males. Among participants ≥ 18 years of age, females with autistic disorder were identified later than males. In more recent years, girls with Asperger's syndrome are diagnosed later than boys, confirming earlier findings. In adults, the delayed timing of diagnosis in females with autistic disorder may be related to changing practices in diagnosis over time. Strategies for changing clinician behaviour to improve recognition of ASD in females are needed. PMID:23001766

  8. Sex Differences in Adult Cognitive Deficits after Adolescent Nicotine Exposure in Rats

    PubMed Central

    Pickens, Laura R. G.; Rowan, James D.; Bevins, Rick A.; Fountain, Stephen B.

    2013-01-01

    This study was designed to determine whether deficits in adult serial pattern learning caused by adolescent nicotine exposure persist as impairments in asymptotic performance, whether adolescent nicotine exposure differentially retards learning about pattern elements that are inconsistent with “perfect” pattern structure, and whether there are sex differences in rats’ response to adolescent nicotine exposure as assessed by a serial multiple choice task. The current study replicated the results of our initial report (Fountain, Rowan, Kelley, Willey, & Nolley, 2008) using this task by showing that adolescent nicotine exposure (1.0 mg/kg/day nicotine for 35 days) produced a specific cognitive impairment in male rats that persisted into adulthood at least a month after adolescent nicotine exposure ended. In addition, sex differences were observed even in controls, with additional evidence that adolescent nicotine exposure significantly impaired learning relative to same-sex controls for chunk boundary elements in males and for violation elements in females. All nicotine-induced impairments were overcome by additional training so that groups did not differ at asymptote. An examination of the types of errors rats made indicated that adolescent nicotine exposure slowed learning without affecting rats’ cognitive strategy in the task. This data pattern suggests that exposure to nicotine in adolescence may have impaired different aspects of adult stimulus-response discrimination learning processes in males and females, but left abstract rule learning processes relatively spared in both sexes. These effects converge with other findings in the field and reinforce the concern that adolescent nicotine exposure poses an important threat to cognitive capacity in adulthood. PMID:23673345

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

    ERIC Educational Resources Information Center

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

    2008-01-01

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

  10. The Profile and Treatment of Male Adolescent Sex Offenders.

    ERIC Educational Resources Information Center

    Lakey, Joyce F.

    1994-01-01

    Outlines characteristics of sex offenders, including family and school histories, sexual attitudes, social skills and relationships, delinquent behaviors, psychiatric diagnoses, and cognitive distortions based on mythical beliefs. Treatment requires correction of thinking errors and promotion of accountability, empathy, education, morality,…

  11. Sex workers’ non-commercial male partners who inject drugs report higher risk sexual behaviors

    PubMed Central

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

    2014-01-01

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

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

    ERIC Educational Resources Information Center

    Martino, Wayne; Frank, Blye

    2006-01-01

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

  13. PERSONALITY AND SUCCESS PROFILES CHARACTERISTIC OF YOUNG ADULT MALE RETARDATES.

    ERIC Educational Resources Information Center

    PECK, JOHN R.; AND OTHERS

    MAJOR SUCCESS-FAILURE SYNDROMES WERE STUDIED FROM DATA OBTAINED IN A PREVIOUS STUDY (COOPERATIVE RESEARCH PROJECT NO. 1533) ON 100 MENTALLY RETARDED, YOUNG MALE ADULTS. STRUCTURED INTERVIEWS HAD BEEN CONDUCTED WITH THE SUBJECTS, THEIR PARENTS, AND THEIR SUPERVISORS. FACTOR ANALYSIS HAD DEVELOPED 21 BASIC PREDICTORS OF SUCCESS AND 17 AFTER-TRAINING…

  14. Outpatient Treatment of Primary Anorexia Nervosa in Adult Males.

    ERIC Educational Resources Information Center

    Ziesat, Harold A., Jr.; Ferguson, James M.

    1984-01-01

    Describes three cases of adult-onset primary anorexia nervosa in males. For each case, the history and diagnostic patterns are considered, followed by a discussion of the course of outpatient treatment. The therapy was multimodal and included elements of behavioral contingency management, cognitive therapy, and dynamic psychotherapy. (JAC)

  15. Prevalence of Childhood Physical Abuse in Adult Male Veteran Alcoholics.

    ERIC Educational Resources Information Center

    Schaefer, Melodie R.; And Others

    1988-01-01

    The study of 100 adult male alcoholics found that about one-third reported they had been physically abused as children. Abused alcoholics reported having more severe psychological symptoms and distress than nonabused counterparts, though they did not differ in the onset, severity, or treatment history for alcohol dependency. (Author/DB)

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

    PubMed Central

    Bar-Johnson, Michael; Weiss, Petr

    2014-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  18. Perinatal Lead Exposure Alters Gut Microbiota Composition and Results in Sex-specific Bodyweight Increases in Adult Mice.

    PubMed

    Wu, Jianfeng; Wen, Xiaoquan William; Faulk, Christopher; Boehnke, Kevin; Zhang, Huapeng; Dolinoy, Dana C; Xi, Chuanwu

    2016-06-01

    Heavy metal pollution is a principle source of environmental contamination. Epidemiological and animal data suggest that early life lead (Pb) exposure results in critical effects on epigenetic gene regulation and child and adult weight trajectories. Using a mouse model of human-relevant exposure, we investigated the effects of perinatal Pb exposure on gut microbiota in adult mice, and the link between gut microbiota and bodyweight changes. Following Pb exposure during gestation and lactation via maternal drinking water, bodyweight in A(vy) strain wild-type non-agouti (a/a) offspring was tracked through adulthood. Gut microbiota of adult mice were characterized by deep DNA sequencing of bacterial 16S ribosomal RNA genes. Data analyses were stratified by sex and adjusted for litter effects. A Bayesian variable selection algorithm was used to analyze associations between bacterial operational taxonomic units and offspring adult bodyweight. Perinatal Pb exposure was associated with increased adult bodyweight in male (P < .05) but not in female offspring (P = .24). Cultivable aerobes decreased and anaerobes increased in Pb-exposed offspring (P < .005 and P < .05, respectively). Proportions of the 2 predominant phyla (Bacteroidetes and Firmicutes) shifted inversely with Pb exposure, and whole bacterial compositions were significantly different (analysis of molecular variance, P < .05) by Pb exposure without sex bias. In males, changes in gut microbiota were highly associated with adult bodyweight (P = .028; effect size = 2.59). Thus, perinatal Pb exposure results in altered adult gut microbiota regardless of sex, and these changes are highly correlated with increased bodyweight in males. Adult gut microbiota can be shaped by early exposures and may contribute to disease risks in a sex-specific manner. PMID:26962054

  19. 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 α-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

  20. Phf7 controls male sex determination in the Drosophila germline

    PubMed Central

    Yang, Shu Yuan; Baxter, Ellen M.; Van Doren, Mark

    2013-01-01

    Summary Establishment of germline sexual identity is critical for production of male and female germline stem cells, and sperm vs. eggs. Here we identify PHD Finger Protein 7 (PHF7) as an important factor for male germline sexual identity in Drosophila. PHF7 exhibits male-specific expression in early germ cells, germline stem cells and spermatogonia. It is required for germline stem cell maintenance and gametogenesis in males, whereas ectopic expression in female germ cells ablates the germline. Strikingly, expression of PHF7 promotes spermatogenesis in XX germ cells when they are present in a male soma. PHF7 homologs are also specifically expressed in the mammalian testis, and human PHF7 rescues Drosophila Phf7 mutants. PHF7 associates with chromatin and both the human and fly proteins bind histone H3 N-terminal tails with a preference for dimethyl lysine 4 (H3K4me2). We propose that PHF7 acts as a conserved epigenetic “reader” that activates the male germline sexual program. PMID:22595675

  1. A further cost for the sicker sex? Evidence for male-biased parasite-induced vulnerability to predation.

    PubMed

    Stephenson, Jessica F; Kinsella, Cormac; Cable, Joanne; van Oosterhout, Cock

    2016-04-01

    Males are typically the sicker sex. Data from multiple taxa indicate that they are more likely to be infected with parasites, and are less "tolerant," or less able to mitigate the fitness costs of a given infection, than females. One cost of infection for many animals is an increased probability of being captured by a predator. A clear, hitherto untested, prediction is therefore that this parasite-induced vulnerability to predation is more pronounced among males than females. We tested this prediction in the sexually size dimorphic guppy, Poecilia reticulata, in which females are typically larger than males. We either sham or experimentally infected guppies with Gyrodactylus turnbulli, elicited their escape response using an established protocol and measured the distance they covered during 60 ms. To discriminate between the effects of body size and those of other inherent sex differences, we size-matched fish across treatment groups. Infection with G. turnbulli reduced the distance covered during the escape response of small adults by 20.1%, whereas that of large fish was unaffected. This result implies that parasite-induced vulnerability to predation is male-biased in the wild: although there was no difference in escape response between our experimentally size-matched groups of males and females, males are significantly smaller across natural guppy populations. These results are consistent with Bateman's principle for immunity: Natural selection for larger body sizes and longevity in females seems to have resulted in the evolution of increased infection tolerance. We discuss the potential implications of sex- and size-biased parasite-induced vulnerability to predation for the evolutionary ecology of this host-parasite interaction in natural communities. PMID:27066240

  2. Human male sex determination and sexual differentiation: pathways, molecular interactions and genetic disorders.

    PubMed

    Kucinskas, Laimutis; Just, Walter

    2005-01-01

    The complex mechanisms are responsible for male sex determination and differentiation. The steps of formation of the testes are dependent on a series of Y-linked, X-linked and autosomal genes actions and interactions. After formation of testes the gonads secrete hormones, which are essential for the formation of the male genitalia. Hormones are transcription regulators, which function by specific receptors. Ambiguous genitalia are result of disruption of genetic interaction. This review describes the mechanisms, which lead to differentiation of male sex and ways by which the determination and differentiation may be interrupted by naturally occurring mutations, causing different syndromes and diseases. PMID:16160410

  3. Patterns of Dating Violence Perpetration and Victimization in U.S. Young Adult Males and Females.

    PubMed

    Spencer, Rachael A; Renner, Lynette M; Clark, Cari Jo

    2016-09-01

    Dating violence (DV) is frequently reported by young adults in intimate relationships in the United States, but little is known about patterns of DV perpetration and victimization. In this study, we examined sexual and physical violence perpetration and victimization reported by young adults to determine how the violence patterns differ by sex and race/ethnicity. Data from non-Hispanic White, non-Hispanic Black, and Hispanic participants in Wave 3 of the National Longitudinal Study of Adolescent to Adult Health were analyzed. DV was assessed using responses to four questions focused on perpetration and four questions focused on victimization. The information on DV was taken from the most violent relationship reported by participants prior to Wave 3. Latent class analysis was first conducted separately by sex, adjusting for age, race/ethnicity, and financial stress, then by race/ethnicity, adjusting for age and financial stress. Relative model fit was established by comparing Bayesian Information Criteria (BIC), adjusted BIC, entropy, interpretability of latent classes, and certainty of latent class assignment for covariate-adjusted models. The results indicate that patterns of violence differed by sex and for females, by race/ethnicity. A three-class model was the best fit for males. For females, separate four-class models were parsimonious for White, Black, and Hispanic females. Financial stress was a significant predictor of violence classification for males and females and age predicted membership in White and Black female models. Variations in DV patterns by sex and race/ethnicity suggest the need for a more nuanced understanding of differences in DV. PMID:25846756

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

    PubMed

    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

  5. Sex- and Subtype-Related Differences in the Comorbidity of Adult ADHDs.

    PubMed

    Groß-Lesch, Silke; Dempfle, Astrid; Reichert, Susanne; Jans, Thomas; Geissler, Julia; Kittel-Schneider, Sarah; Nguyen, Thuy Trang; Reif, Andreas; Lesch, Klaus-Peter; Jacob, Christian Peter

    2013-11-01

    Objective: Comorbidity in adult ADHD (aADHD) has been investigated in a large number of studies using varying research approaches with divergent results. In contrast, there is limited information about sex- or subtype-related differences from studies with small sample size. Method: A large sample of 910 individuals (458 males, 452 females) affected with aADHD was recruited at a tertiary referral center. All probands underwent a four-step procedure for diagnosing aADHD, including the Structured Clinical Interview of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) Axis I disorders to assess comorbidity. This study will provide additional information regarding the co-morbidity of Axis I disorders in the currently largest clinical referral sample. However, the main objective of this study is to gain information about sex- or subtype-related differences. Results: Affected females show higher rates of mood (61% vs. 49%), anxiety (32% vs. 22%), and eating disorders (16% vs. 1%) than affected males, while substance use disorders were more frequent in affected males (45% vs. 29%), which mirrors sex differences in prevalence in the general population. There were hardly any relevant differences in comorbidities between subtypes, with the exception of the inattentive subtype having an especially low prevalence of panic disorder. Comorbidity in general and substance use disorders in particular, but not sex or subtype, were highly predictive of lower psychosocial status. Conclusion: Sex-related differences in the comorbidity of aADHD are more pronounced than subtype-related differences. (J. of Att. Dis. XXXX; XX(X) XX-XX). PMID:24196345

  6. Observations on sex ratio and behavior of males in Xyleborinus saxesenii Ratzeburg (Scolytinae, Coleoptera)

    PubMed Central

    H.W. Biedermann, Peter

    2010-01-01

    Abstract Strongly female-biased sex ratios are typical for the fungalfeeding haplodiploid Xyleborini (Scolytinae, Coleoptera), and are a result of inbreeding and local mate competition (LMC). These ambrosia beetles are hardly ever found outside of trees, and thus male frequency and behavior have not been addressed in any empirical studies to date. In fact, for most species the males remain undescribed. Data on sex ratios and male behavior could, however, provide important insights into the Xyleborini’s mating system and the evolution of inbreeding and LMC in general. In this study, I used in vitro rearing methods to obtain the first observational data on sex ratio, male production, male and female dispersal, and mating behavior in a xyleborine ambrosia beetle. Females of Xyleborinus saxesenii Ratzeburg produced between 0 and 3 sons per brood, and the absence of males was relatively independent of the number of daughters to be fertilized and the maternal brood sex ratio. Both conformed to a strict LMC strategy with a relatively precise and constant number of males. If males were present they eclosed just before the first females dispersed, and stayed in the gallery until all female offspring had matured. They constantly wandered through the gallery system, presumably in search of unfertilized females, and attempted to mate with larvae, other males, and females of all ages. Copulations, however, only occurred with immature females. From galleries with males, nearly all females dispersed fertilized. Only a few left the natal gallery without being fertilized, and subsequently went on to produce large and solely male broods. If broods were male-less, dispersing females always failed to found new galleries. PMID:21594184

  7. 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

  8. Age- and sex-related changes in vibrotactile sensitivity of hand and face in neurotypical adults.

    PubMed

    Venkatesan, Lalit; Barlow, Steven M; Kieweg, Douglas

    2015-01-01

    Sensory perception decreases with age, and is altered as a function of sex. Very little is known about the age- and sex-related changes in vibrotactile detection thresholds (VDTs) of the face relative to the glabrous hand. This study utilized a single-interval up/down (SIUD) adaptive procedure to estimate the VDT for mechanical stimuli presented at 5, 10, 50, 150, 250, and 300 Hz at two sites on the face, including the right non-glabrous surface of the oral angle and the right lower lip vermilion; and on the hand on the glabrous surface of the distal phalanx of the right dominant index finger. Eighteen right-handed healthy younger adults and 18 right-handed healthy older adults participated in this study. VDTs were significantly different between the three stimulus sites (p < 0.0001), and dependent on stimulus frequency (p < 0.0001) and the sex of the participants (p < 0.005). VDTs were significantly higher for older adults when compared to younger adults for the finger stimulation condition (p < 0.05). There were significant differences (p < 0.05) in cheek and lower lip VDTs between male and female subjects. Difference in the VDTs between the three stimulation sites is presumed to reflect the unique typing and distribution of mechanoreceptors in the face and hand. Age-related differences in finger skin sensitivity are likely due to changes in the physical structure of skin, changes in the number and morphology of the mechanoreceptors, differences in the functional use of the hand, and its central representation. Sex-related differences in the VDTs may be due to the differences in tissue conformation and thickness, mechanoreceptor densities, skin hydration, or temperature characteristics. PMID:25248543

  9. Effect of Withania somnifera (L.) Dunal on Sex Hormone and Gonadotropin Levels in Addicted Male Rats

    PubMed Central

    Rahmati, Batool; Ghosian Moghaddam, Mohammad Hassan; Khalili, Mohsen; Enayati, Ehsan; Maleki, Maryam; Rezaeei, Saeedeh

    2016-01-01

    Background Opioid consumption has been widely increasing across the globe; how- ever, it can cause adverse effects on the body. Morphine, an opioid, can reduce sex hor- mones and fertility. Withania somnifera (WS) is a traditional herb used to improve sexual activities. This study strives to investigate the effect of WS on sex hormones and gonado- tropins in addicted male rats. Materials and Methods In this experimental study, forty-eight male National Maritime Research Institute (NMRI) rats were randomly divided into four groups: i. Control group, ii. WS-treated control group, iii. Addicted group, and iv. WS-treated addicted group. Wa- ter-soluble morphine was given to rats for 21 days to induce addiction, concurrently the treated groups (2 and 4) also received WS plant-mixed pelleted food (6.25%). At the end of the treatment, the sex hormone and gonadotropin levels of the rats’ sera were deter- mined in all the groups. Results Except for follicle-stimulating hormone (FSH), morphine reduced most of the gonadotropin and sex hormone levels. Whereas WS caused a considerable increase in the hormones in the treated addicted group, there was only a slight increase in the treated control group. Conclusion WS increased sex hormones and gonadotropins-especially testosterone, es- trogen, and luteinizing hormone-in the addicted male rats and even increased the proges- terone level, a stimulant of most sex hormones in addicted male rats. PMID:27441058

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

    PubMed Central

    Li, Qing; Li, Xiaoming; Stanton, Bonita

    2010-01-01

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

  11. Sex recognition and mate choice by male Bufo gargarizans in central China.

    PubMed

    Yu, Tong Lei; Sharma, Manmohan D

    2012-06-01

    Mate choice is important for successful reproduction, and consequently species have evolved various ways to choose potential high-quality mates. Anuran mate choice and underlying processes have been the subject of several recent investigations, however we are far from a complete understanding of mate choice in this system. In the present study, when given a simultaneous choice between a male and a female of identical size, males did not discriminate between the sexes, and attempted to clasp a male or a female with equal frequency. Test males only released the stimulus toad when a release call was emitted by the stimulus male. When two males with distinct size differences were provided with a male, the male chose the larger one. Moreover, males discriminated between gravid females that differed in body size, choosing larger gravid females over smaller ones. These results suggest that male Bufo gargarizans can discriminate between the sexes, probably based on male release calls, and prefer to mate with larger individual using visual cues. PMID:22639803

  12. The systemizing quotient: an investigation of adults with Asperger syndrome or high-functioning autism, and normal sex differences.

    PubMed Central

    Baron-Cohen, Simon; Richler, Jennifer; Bisarya, Dheraj; Gurunathan, Nhishanth; Wheelwright, Sally

    2003-01-01

    Systemizing is the drive to analyse systems or construct systems. A recent model of psychological sex differences suggests that this is a major dimension in which the sexes differ, with males being more drawn to systemize than females. Currently, there are no self-report measures to assess this important dimension. A second major dimension of sex differences is empathizing (the drive to identify mental states and respond to these with an appropriate emotion). Previous studies find females score higher on empathy measures. We report a new self-report questionnaire, the Systemizing Quotient (SQ), for use with adults of normal intelligence. It contains 40 systemizing items and 20 control items. On each systemizing item, a person can score 2, 1 or 0, so the SQ has a maximum score of 80 and a minimum of zero. In Study 1, we measured the SQ of n = 278 adults (114 males, 164 females) from a general population, to test for predicted sex differences (male superiority) in systemizing. All subjects were also given the Empathy Quotient (EQ) to test if previous reports of female superiority would be replicated. In Study 2 we employed the SQ and the EQ with n = 47 adults (33 males, 14 females) with Asperger syndrome (AS) or high-functioning autism (HFA), who are predicted to be either normal or superior at systemizing, but impaired at empathizing. Their scores were compared with n = 47 matched adults from the general population in Study 1. In Study 1, as predicted, normal adult males scored significantly higher than females on the SQ and significantly lower on the EQ. In Study 2, again as predicted, adults with AS/HFA scored significantly higher on the SQ than matched controls, and significantly lower on the EQ than matched controls. The SQ reveals both a sex difference in systemizing in the general population and an unusually strong drive to systemize in AS/HFA. These results are discussed in relation to two linked theories: the 'empathizing-systemizing' (E-S) theory of sex

  13. 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

  14. Sex, but not Apolipoprotein E Polymorphism, Differences in Spatial Performance in Young Adults.

    PubMed

    Yasen, Alia L; Raber, Jacob; Miller, Jeremy K; Piper, Brian J

    2015-11-01

    The purpose of this study was to examine how sex and apolipoprotein E (APOE) genotype contribute to individual differences in spatial learning and memory. The associations of APOE genotype with neurocognitive function have been well studied among the elderly but less is known at earlier ages. Young adults (n = 169, 88 females) completed three neurocognitive tasks: mental rotation, spatial span, and Memory Island, a spatial navigation test. Males outperformed females on all three tasks: finding the hidden targets more quickly on Memory Island (Cohen's d = 0.62) and obtaining higher scores on mental rotation (d = 0.54) and spatial span (d = 0.37). In contrast, no significant effects of APOE were observed. The identified sex differences elaborate upon past literature documenting sexually dimorphic performance on specific neurobehavioral tasks. PMID:25750133

  15. 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.

  16. 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

  17. 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

  18. Identification of a sex attractant pheromone for male winterform pear psylla, Cacopsylla pyricola.

    PubMed

    Guédot, Christelle; Millar, Jocelyn G; Horton, David R; Landolt, Peter J

    2009-12-01

    Pear psylla, Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae), a major economic pest of pears, uses a female-produced sex attractant pheromone. We compared the chemical profiles obtained from cuticular extracts of diapausing and post-diapause winterform males and females to isolate and identify the pheromone. Post-diapause females produced significantly more of the cuticular hydrocarbon, 13-methylheptacosane, than post-diapause males and diapausing females. In olfactometer assays, conspecific males were attracted to synthetic racemic 13-methylheptacosane, whereas females were not, indicating that the behavioral response to this chemical is sex-specific. Furthermore, 13-methylheptacosane was as attractive to males as a cuticular extract of females, suggesting that this chemical was largely responsible for the female attractiveness. A field study showed that males but not females were attracted to 13-methylheptacosane, confirming the olfactometer results. This study provides evidence that 13-methylheptacosane is a sex attractant pheromone for C. pyricola winterform males. This is the first identification of a sex pheromone in the Psylloidea. Our results open the path to developing monitoring tools and possibly new strategies for integrated pest management of this insect. PMID:20063206

  19. Innate immunity is not related to the sex of adult Tree Swallows during the nestling period

    USGS Publications Warehouse

    Houdek, Bradley J.; Lombardo, Michael P.; Thorpe, Patrick A.; Hahn, D. Caldwell

    2011-01-01

    Evolutionary theory predicts that exposure to more diverse pathogens will result in the evolution of a more robust immune response. We predicted that during the breeding season the innate immune function of female Tree Swallows (Tachycineta bicolor) should be more effective than that of males because (1) the transmission of sexually transmitted microbes during copulation puts females at greater risk because ejaculates move from males to females, (2) females copulate with multiple males, exposing them to the potentially pathogenic microbes in semen, and (3) females spend more time in the nest than do males so may be more exposed to nest microbes and ectoparasites that can be vectors of bacterial and viral pathogens. In addition, elevated testosterone in males may suppress immune function. We tested our prediction during the 2009 breeding season with microbicidal assays in vitro to assess the ability of the innate immune system to kill Escherichia coli. The sexes did not differ in the ability of their whole blood to kill E. coli. We also found no significant relationships between the ability of whole blood to kill E. coli and the reproductive performance or the physical condition of males or females. These results indicate that during the nestling period there are no sexual differences in this component of the innate immune system. In addition, they suggest that there is little association between this component of innate immunity and the reproductive performance and physical condition during the nestling period of adult Tree Swallows.

  20. Innate immunity is not related to the sex of adult Tree Swallows during the nestling period

    USGS Publications Warehouse

    Houdek, B.J.; Lombardo, M.P.; Thorpe, P.A.; Hahn, D.C.

    2011-01-01

    Evolutionary theory predicts that exposure to more diverse pathogens will result in the evolution of a more robust immune response. We predicted that during the breeding season the innate immune function of female Tree Swallows (Tachycineta bicolor) should be more effective than that of males because (1) the transmission of sexually transmitted microbes during copulation puts females at greater risk because ejaculates move from males to females, (2) females copulate with multiple males, exposing them to the potentially pathogenic microbes in semen, and (3) females spend more time in the nest than do males so may be more exposed to nest microbes and ectoparasites that can be vectors of bacterial and viral pathogens. In addition, elevated testosterone in males may suppress immune function. We tested our prediction during the 2009 breeding season with microbicidal assays in vitro to assess the ability of the innate immune system to kill Escherichia coli. The sexes did not differ in the ability of their whole blood to kill E. coli. We also found no significant relationships between the ability of whole blood to kill E. coli and the reproductive performance or the physical condition of males or females. These results indicate that during the nestling period there are no sexual differences in this component of the innate immune system. In addition, they suggest that there is little association between this component of innate immunity and the reproductive performance and physical condition during the nestling period of adult Tree Swallows. ?? The Cooper Ornithological Society 2011.

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

    PubMed Central

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

    2011-01-01

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

  2. Sex-specific attentional deficits in adult vitamin D deficient BALB/c mice.

    PubMed

    Groves, Natalie J; Burne, Thomas H J

    2016-04-01

    Epidemiological studies have shown an association between vitamin D deficiency and cognitive impairment. However, there is a paucity of preclinical data showing that vitamin D deficiency is a causal factor for impaired cognitive processing. The aim of this study was to assess two cognitive tasks, the 5 choice-serial reaction task and the 5 choice-continuous performance task in adult vitamin D (AVD) deficient BALB/c mice. Ten-week old male and female BALB/c mice were fed a control or vitamin D deficient diet for 10 weeks prior to, and during behavioural testing. We found sex-dependent impairments in attentional processing and showed that male AVD-deficient mice were less accurate, took longer to respond when making a correct choice and were more likely to make an omission, without a change in the motivation to collect reward. By contrast, female AVD-deficient mice had a reduced latency to collect reward, but no changes on any other measures compared to controls. Therefore, we have shown that in otherwise healthy adult mice, vitamin D deficiency led to mild cognitive impairment in male but not female mice and therefore this model will be useful for future investigations into unravelling the mechanism by which vitamin D affects the adult brain and cognitive function. PMID:26836278

  3. 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. PMID:27019728

  4. 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

  5. The role of non-coding RNAs in male sex determination and differentiation.

    PubMed

    Rastetter, Raphael H; Smith, Craig A; Wilhelm, Dagmar

    2015-09-01

    A complex network of gene regulation and interaction drives male sex determination and differentiation. While many important protein-coding genes that are necessary for proper male development have been identified, many disorders in human sex development are still unexplained at the molecular level. This suggests that key factors and regulatory mechanisms are still unknown. In recent years, extensive data have shown that different classes of non-coding RNAs (ncRNAs) play a role in almost all developmental and physiological pathways. Here we review what is known about their role in male sex determination and differentiation not only in mammals, but also other species. While for some processes a key role for ncRNA has been identified, we are still far from having a complete picture. PMID:25995439

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

    PubMed

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

    2016-01-01

    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

  7. Effect of estrogen receptor-subtype-specific ligands on fertility in adult male rats.

    PubMed

    Dumasia, Kushaan; Kumar, Anita; Kadam, Leena; Balasinor, N H

    2015-06-01

    Maintenance of normal male fertility relies on the process of spermatogenesis which is under complex endocrine control by mechanisms involving gonadotropin and steroid hormones. Although testosterone is the primary sex steroid in males, estrogen is locally produced in the testis and plays a very crucial role in male fertility. This is evident from presence of both the estrogen receptors alpha (ERα) and beta (ERβ) in the testis and their absence, as in the case of knockout mice models, leads to sterility. The present study was undertaken to understand individual roles of the two ERs in spermatogenesis and their direct contribution towards the maintenance of male fertility using receptor-subtype-specific ligands. Administration of ERα and β agonists to adult male rats for 60 days results in a significant decrease in fertility, mainly due to an increase in pre- and post-implantation loss and a concomitant decrease in litter size and sperm counts. Our results indicate that ERα is mainly involved in negative feedback regulation of gonadotropin hormones, whereas both ERs are involved in regulation of prolactin and testosterone production. Histological examinations of the testis reveal that ERβ could be involved in the process of spermiation since many failed spermatids were observed in stages IX-XI following ERβ agonist treatment. Our results indicate that overactivation of estrogen signaling through either of its receptors can have detrimental effects on the fertility parameters and that the two ERs have both overlapping and distinct roles in maintenance of male fertility. PMID:25869617

  8. Possible Secondary Population-Level Effects of Selective Harvest of Adult Male Muskoxen

    PubMed Central

    Schmidt, Joshua H.; Gorn, Tony S.

    2013-01-01

    Selective harvest regimes are often focused on males resulting in skewed sex-ratios, and for many ungulate species this strategy is sustainable. However, muskoxen (Ovibos moschatus) are very social and mature bulls (≥4 years old), particularly prime-age bulls (6–10 years old), play important roles in predator defense and recruitment. A year-round social structure incorporating large males into mixed-sex groups could make this species more susceptible to the effects of selective harvest if population composition and sex-ratios influence overall survival and reproductive success. Using detailed data collected on the muskox population occupying the Seward Peninsula, Alaska during 2002–2012, we formulated the hypothesis that the selective harvest of mature bulls may be related to documented changes in population composition and growth rates in this species. In addition, we reviewed existing published information from two other populations in Alaska, the Cape Thompson and Northeastern populations, to compare population growth rates among the three areas under differential harvest rates relative to our hypothesis. We found that on the Seward Peninsula, mature bull:adult cow ratios declined 4–12%/year and short-yearling:adult cow ratios (i.e., recruitment) declined 8–9%/year in the most heavily harvested areas. Growth rates in all 3 populations decreased disproportionately after increases in the number of bulls harvested, and calf:cow ratios declined in the Northeastern population as harvest increased. While lack of appropriate data prevented us from excluding other potential causes such as density dependent effects and changes in predator densities, our results did align with our hypothesis, suggesting that in the interest of conservation, harvest of mature males should be restricted until causal factors can be more definitively identified. If confirmed by additional research, our findings would have important implications for harvest management and

  9. 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

  10. Male and female mate choice affects offspring quality in a sex-role-reversed pipefish.

    PubMed

    Sandvik, M; Rosenqvist, G; Berglund, A

    2000-11-01

    Where both sexes invest substantially in offspring, both females and males should discriminate between potential partners when choosing mates. The degree of choosiness should relate to the costs of choice and to the potential benefits to be gained. We measured offspring quality from experimentally staged matings with preferred and non-preferred partners in a sex-role-reversed pipefish, Syngnathus typhle L. Here, a substantial male investment in offspring results in a lower potential reproductive rate in males than in females, and access to males limits female reproductive success rather than vice versa. Thus, males are choosier than females and females compete more intensely over mates than do males. Broods from preferred matings were superior at escaping predation, when either males or females were allowed to choose a partner. However, only 'choosing' females benefited in terms of faster-growing offspring. Our results have important implications for mate-choice research: here we show that even the more competitive and less choosy sex may contribute significantly to sexual selection through mate choice. PMID:11413626

  11. 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

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

    PubMed Central

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

    2015-01-01

    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

  13. The Jak-STAT target Chinmo prevents sex transformation of adult stem cells in the Drosophila testis niche

    PubMed Central

    Ma, Qing; Wawersik, Matthew; Matunis, Erika L.

    2014-01-01

    Local signals maintain adult stem cells in many tissues. Whether the sexual identity of adult stem cells must also be maintained was not known. In the adult Drosophila testis niche, local Jak-STAT signaling promotes somatic cyst stem cell (CySC) renewal through several effectors, including the putative transcription factor Chronologically inappropriate morphogenesis (Chinmo). Here, we find that Chinmo also prevents feminization of CySCs. Chinmo promotes expression of the canonical male sex determination factor DoublesexM (DsxM) within CySCs and their progeny, and ectopic expression of DsxM in the CySC lineage partially rescues the chinmo sex transformation phenotype, placing Chinmo upstream of DsxM. The Dsx homologue DMRT1 prevents the male-to female conversion of differentiated somatic cells in the adult mammalian testis, but its regulation is not well understood. Our work indicates that sex maintenance occurs in adult somatic stem cells, and that this highly conserved process is governed by effectors of niche signals. PMID:25453558

  14. Sex-differential placentation immunological interactions between male conceptus and gravida during normal pregnancy.

    PubMed

    Vernier, M C

    1975-01-01

    7,773 placentae of newborns were analyzed in order to test a hypothesis of specific immunological concepto-maternal interactions due to maleness and occurring during normal pregnancy. An association between placental weight of newborn male and the sex of conceptuses of previous pregnancies was found which supports the hypothesis. No such an association was found for female newborn. The confirmation of these results could open new avenues in the study of sex-differential survival of the conceptus throughout gestation. PMID:1148342

  15. Juvenile Hormone Is Required in Adult Males for Drosophila Courtship

    PubMed Central

    Wijesekera, Thilini P.; Saurabh, Sumit; Dauwalder, Brigitte

    2016-01-01

    Juvenile Hormone (JH) has a prominent role in the regulation of insect development. Much less is known about its roles in adults, although functions in reproductive maturation have been described. In adult females, JH has been shown to regulate egg maturation and mating. To examine a role for JH in male reproductive behavior we created males with reduced levels of Juvenile Hormone Acid O-Methyl Transferase (JHAMT) and tested them for courtship. JHAMT regulates the last step of JH biosynthesis in the Corpora Allata (CA), the organ of JH synthesis. Males with reduced levels of JHAMT showed a reduction in courtship that could be rescued by application of Methoprene, a JH analog, shortly before the courtship assays were performed. In agreement with this, reducing JHAMT conditionally in mature flies led to courtship defects that were rescuable by Methoprene. The same result was also observed when the CA were conditionally ablated by the expression of a cellular toxin. Our findings demonstrate that JH plays an important physiological role in the regulation of male mating behavior. PMID:27003411

  16. Behavioral and physiological female responses to male sex ratio bias in a pond-breeding amphibian

    PubMed Central

    2012-01-01

    Introduction The phenomenon of sexual conflict has been well documented, and in populations with biased operational sex ratios the consequences for the rarer sex can be severe. Females are typically a limited resource and males often evolve aggressive mating behaviors, which can improve individual fitness for the male while negatively impacting female condition and fitness. In response, females can adjust their behavior to minimize exposure to aggressive mating tactics or minimize the costs of mating harassment. While male-male competition is common in amphibian mating systems, little is known about the consequences or responses of females. The red-spotted newt (Notophthalmus viridescens) is a common pond-breeding amphibian with a complex, well-studied mating system where males aggressively court females. Breeding populations across much of its range have male-biased sex ratios and we predicted that female newts would have behavioral mechanisms to mitigate mating pressure from males. We conducted four experiments examining the costs and behavioral responses of female N. viridescens exposed to a male-biased environment. Results In field enclosures, we found that female newts exposed to a male-biased environment during the five-month breeding season ended with lower body condition compared to those in a female-biased environment. Shorter-term exposure to a male-biased environment for five weeks caused a decrease in circulating total leukocyte and lymphocyte abundance in blood, which suggests females experienced physiological stress. In behavioral experiments, we found that females were more agitated in the presence of male chemical cues and females in a male-biased environment spent more time in refuge than those in a female-biased environment. Conclusions Our results indicate that male-biased conditions can incur costs to females of decreased condition and potentially increased risk of infection. However, we found that females can also alter their behavior and

  17. Mating system and sex ratios of a pollinating fig wasp with dispersing males.

    PubMed Central

    Greeff, Jaco M

    2002-01-01

    Recent studies have used sex ratios to quantify the mating systems of organisms, the argument behind it being that more female-biased sex ratios are an indication of higher local mate competition, which goes hand-in-hand with higher levels of inbreeding. Although qualitative tests of the effects of mating systems on sex ratios abound, there is a dearth of studies that quantify both the mating system and the sex ratio. I use a colour dimorphism with a simple Mendelian inheritance to quantify the mating system of an unusual fig-pollinating wasp in which males disperse to obtain matings on non-natal mating patches. In qualitative agreement with initial expectations, the sex ratios of single foundresses are found to be higher than those of regular species. However, by quantifying the mating system, it is shown that the initial expectation is incorrect and this species' sex ratio is a poor predictor of its mating system (it underestimates the frequency of sib-mating). The species has a very high variance in sex ratio suggesting that excess males can simply avoid local mate competition (and hence a lowered fitness to their mother) by dispersing to other patches. PMID:12495498

  18. Effects of In Utero Exposure to Bisphenol A or Diethylstilbestrol on the Adult Male Reproductive System

    PubMed Central

    LaRocca, Jessica; Boyajian, Alanna; Brown, Caitlin; Smith, Stuart Duncan; Hixon, Mary

    2011-01-01

    The objective of this study was to determine if in utero exposure to Bisphenol A (BPA) induced reproductive tract abnormalities in the adult male testis. Using the C57/Bl6 mouse, we examined sex-organ weights, anogenital distance (AGD), and testis histopathology in adult males exposed in utero via oral gavage to sesame oil, 50 μg/kg BPA, 1,000 μg/kg BPA, or 2 μg/kg diethylstilbestrol (DES) as a positive control from gestational days 10–16. No changes in sperm production or germ cell apoptosis were observed in adult testes following exposure to either chemical. Adult mRNA levels of genes associated with sexual maturation and differentiation, GATA4 and ID2, were significantly lower only in DES-exposed testes. In summary, the data indicate no gross alterations in spermatogenesis following in utero exposure to BPA or DES. At the molecular level, in utero exposure to DES, but not BPA, leads to decreased mRNA expression of genes associated with Sertoli cell differentiation. PMID:21922642

  19. 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

  20. Adult romantic relationships as contexts of human development: a multimethod comparison of same-sex couples with opposite-sex dating, engaged, and married dyads.

    PubMed

    Roisman, Glenn I; Clausell, Eric; Holland, Ashley; Fortuna, Keren; Elieff, Chryle

    2008-01-01

    This article presents a multimethod, multi-informant comparison of community samples of committed gay male (n=30) and lesbian (n=30) couples with both committed (n=50 young engaged and n=40 older married) and noncommitted (n=109 exclusively dating) heterosexual pairs. Specifically, in this study the quality of same- and opposite-sex relationships was examined at multiple levels of analysis via self-reports and partner reports, laboratory observations, and measures of physiological reactivity during dyadic interactions. Additionally, individuals in same-sex, engaged, and marital relationships were compared with one another on adult attachment security as assessed through the coherence of participants' narratives about their childhood experiences. Results indicated that individuals in committed same-sex relationships were generally not distinguishable from their committed heterosexual counterparts, with one exception--lesbians were especially effective at working together harmoniously in laboratory observations. PMID:18194008

  1. Sex differences in cognitive trajectories in clinically normal older adults.

    PubMed

    McCarrey, Anna C; An, Yang; Kitner-Triolo, Melissa H; Ferrucci, Luigi; Resnick, Susan M

    2016-03-01

    Age effects on cognitive functioning are well-documented, but effects of sex on trajectories of cognitive aging are less clear. We examined cognitive ability across a variety of measures for 1,065 to 2,127 participants (mean baseline age 64.1 to 69.7 years) from the Baltimore Longitudinal Study of Aging who were repeatedly tested over a mean follow-up interval of 3.0 to 9.0 years with a mean of 2.3 to 4.4 assessments. Memory and other cognitive tests were administered at each visit, assessing mental status, verbal learning and memory, figural memory, language, attention, perceptuomotor speed and integration, executive function, and visuospatial ability. Importantly, participants free from cognitive impairment at all time points were used in the analyses. Results showed that for all tests, higher age at baseline was significantly associated with lower scores, and performance declined over time. In addition, advancing age was associated with accelerated longitudinal declines in performance (trend for mental status). After adjusting for age, education, and race, sex differences were observed across most tests of specific cognitive abilities examined. At baseline, males outperformed females on the 2 tasks of visuospatial ability, and females outperformed males in most other tests of cognition. Sex differences in cognitive change over time indicated steeper rates of decline for men on measures of mental status, perceptuomotor speed and integration, and visuospatial ability, but no measures on which women showed significantly steeper declines. Our results highlight greater resilience to age-related cognitive decline in older women compared with men. PMID:26796792

  2. BISPHENOL A EXPOSURE DURING EARLY DEVELOPMENT INDUCES SEX-SPECIFIC CHANGES IN ADULT ZEBRAFISH SOCIAL INTERACTIONS

    PubMed Central

    Weber, Daniel N.; Hoffmann, Raymond G.; Hoke, Elizabeth S.; Tanguay, Robert L.

    2014-01-01

    Developmental bisphenol A (BPA) exposure is associated with adverse behavioral effects, although underlying modes of action remain unclear. Because BPA is a suspected xenoestrogen, the objective was to identify sex-based changes in adult zebrafish social behavior developmentally exposed to BPA (0.0, 0.1 or 1 μM) or one of two control compounds (0.1μM 17β-estradiol [E2], and 0.1 μM GSK4716, a synthetic estrogen-related receptor γ ligand). A test chamber was divided lengthwise so each arena held one fish unable to detect the presence of the other fish. A mirror was inserted at one end of each arena; baseline activity levels were determined without mirror. Arenas were divided into 3, computer-generated zones to represent different distances from mirror image. Circadian rhythm patterns were evaluated at 1–3 (= AM) and 5–8 (= PM) hr postprandial. Adult zebrafish were placed into arenas and monitored by digital camera for 5 min. Total distance traveled, % time spent at mirror image, and number of attacks on mirror image were quantified. E2, GSK4716, and all BPA treatments dampened male activity and altered male circadian activity patterns; there was no marked effect on female activity. BPA induced non-monotonic effects (response curve changes direction within range of concentrations examined) on male % time at mirror only in AM. All treatments produced increased % time at the mirror during PM. Male attacks on the mirror were reduced by BPA exposure only during AM. There were sex-specific effects of developmental BPA on social interactions and time-of-day of observation affected results. PMID:25424546

  3. Differential Effects of Sex Pheromone Compounds on Adult Female Sea Lamprey (Petromyzon marinus) Locomotor Patterns.

    PubMed

    Walaszczyk, Erin J; Goheen, Benjamin B; Steibel, Juan Pedro; Li, Weiming

    2016-06-01

    Synchronization of male and female locomotor activity plays a critical role in ensuring reproductive success, especially in semelparous species. The goal of this study was to elucidate the effects of individual chemical signals, or pheromones, on the locomotor activity in the sea lamprey (Petromyzon marinus). In their native habitat, adult preovulated females (POF) and ovulated females (OF) are exposed to sex pheromone compounds that are released from spermiated males and attract females to nests during their migration and spawning periods. In this study, locomotor activity of individual POF and OF was measured hourly in controlled laboratory conditions using an automated video-tracking system. Differences in the activity between a baseline day (no treatment exposure) and a treatment day (sex pheromone compound or control exposure) were examined for daytime and nighttime periods. Results showed that different pheromone compound treatments affected both POF and OF sea lamprey (p < 0.05) but in different ways. Spermiated male washings (SMW) and one of its main components, 7α,12α,24-trihydroxy-5α-cholan-3-one 24 sulfate (3kPZS), decreased activity of POF during the nighttime. SMW also reduced activity in POF during the daytime. In contrast, SMW increased activity of OF during the daytime, and an additional compound found in SMW, petromyzonol sulfate (PZS), decreased the activity during the nighttime. In addition, we examined factors that allowed us to infer the overall locomotor patterns. SMW increased the maximum hourly activity during the daytime, decreased the maximum hourly activity during the nighttime, and reduced the percentage of nocturnal activity in OF. Our findings suggest that adult females have evolved to respond to different male compounds in regards to their locomotor activity before and after final maturation. This is a rare example of how species-wide chemosensory stimuli can affect not only the amounts of activity but also the overall locomotor

  4. Early life stress induces renal dysfunction in adult male rats but not female rats

    PubMed Central

    Loria, Analia S.; Yamamoto, Tatsuo; Pollock, Jennifer S.

    2013-01-01

    Maternal separation (MatSep) is a model of behavioral stress during early life. We reported that MatSep exacerbates ANG II-induced hypertension in adult male rats. The aims of this study were to determine whether exposure to MatSep in female rats sensitizes blood pressure to ANG II infusion similar to male MatSep rats and to elucidate renal mechanisms involved in the response in MatSep rats. Wistar Kyoto (WKY) pups were exposed to MatSep 3 h/day from days 2 to 14, while control rats remained with their mothers. ANG II-induced mean arterial pressure (MAP; telemetry) was enhanced in female MatSep rats compared with control female rats but delayed compared with male MatSep rats. Creatinine clearance (Ccr) was reduced in male MatSep rats compared with control rats at baseline and after ANG II infusion. ANG II infusion significantly increased T cells in the renal cortex and greater histological damage in the interstitial arteries of male MatSep rats compared with control male rats. Plasma testosterone was greater and estradiol was lower in male MatSep rats compared with control rats with ANG II infusion. ANG II infusion failed to increase blood pressure in orchidectomized male MatSep and control rats. Female MatSep and control rats had similar Ccr, histological renal analysis, and sex hormones at baseline and after ANG II infusion. These data indicate that during ANG II-induced hypertension, MatSep sensitizes the renal phenotype in male but not female rats. PMID:23174859

  5. Treatment of changes on male sex organs with CO2 and Nd:YAG laser

    NASA Astrophysics Data System (ADS)

    Wozniak, Jakub; Rzymski, Pawel; Opala, Tomasz; Wilczak, Maciej; Sajdak, Stefan

    2003-10-01

    The aim of our study was to evaluate treatment of changes on male sex organs with CO2 and Nd:YAG lasers. Material consisted of 34 male patients of Diagnostic and Observational Department of Gynecologic and Obstetrical University Hospital in Poznan, Poland treated between 1998 and 2002. Results of treatment with both lasers were similar when comparing therapeutic effect and side effects. No complication was noticed and the observed differences were not statistically significant.

  6. Operational sex ratio and density do not affect directional selection on male sexual ornaments and behavior.

    PubMed

    Head, Megan L; Lindholm, Anna K; Brooks, Robert

    2008-01-01

    Demographic parameters including operational sex ratio (OSR) and population density may influence the opportunity for, and strength of sexual selection. Traditionally, male-biased OSRs and high population densities have been thought to increase the opportunity for sexual selection on male sexual traits due to increased male competition for mates. Recent experimental evidence, however, suggests that male-biased OSRs might reduce the opportunity for sexual selection due to increased sexual coercion experienced by females. How OSR, density, and any resultant changes in the opportunity for sexual selection actually affect selection on male sexual traits is unclear. In this study, we independently manipulated OSR and density in the guppy (Poecilia reticulata) without altering the number of males present. We recorded male and female behavior and used DNA microsatellite data to assign paternity to offspring and estimate male reproductive success. We then used linear selection analyses to examine the effects of OSR and density on directional sexual selection on male behavioral and morphological traits. We found that females were pursued more by males in male-biased treatments, despite no change in individual male behavior. There were no differences in sexual behavior experienced by females or performed by males in relation to density. Neither OSR nor density significantly altered the opportunity for sexual selection. Also, Although there was significant multivariate linear selection operating on males, neither OSR nor density altered the pattern of sexual selection on male traits. Our results suggest that differences in either OSR or density (independent of the number of males present) are unlikely to alter directional evolutionary change in male sexual traits. PMID:18067568

  7. "Aging males" symptoms and general health of adult males: a cross-sectional study.

    PubMed

    Yuen, John W; Ng, Chi-Fai; Chiu, Peter Ka Fung; Teoh, Jeremy Yuen Chun; Yee, C H

    2016-06-01

    A cross-sectional study was conducted to explore the prevalence and severity of health-related complaints perceived by adult males of Hong Kong by using the Hong Kong Traditional Chinese versions of the Aging males' symptoms (AMS) scale and the 5-dimensional and 3-level European Quality of life (EQ-5D-3L) questionnaire. A total of 825 adult males aged 40 years or above were surveyed, and observed that 80% of the population was living with little-to-mild levels of aging symptoms with mean total scores ranged between 26.02 ± 7.91 and 32.99 ± 7.91 in different age groups. Such symptoms were correlated with age, especially for the somato-vegetative and sexual symptoms. The most severe AMS symptoms were observed in the oldest age group at 70 years or above, with 76%, 34% and 70% living with moderate-to-severe levels of somato-vegetative, psychological and sexual symptoms, respectively. The result was highly correlated with the EQ-5D-3L questionnaire. Secondly, the Hong Kong Aging males' symptoms (AMS) scale was shown to have good reliability with test-retest coefficient at 0.79 (ranged 0.66-0.87) and Cronbach's alpha coefficient at 0.88 (ranged 0.70-0.84). In summary, the population of Hong Kong male adults was commonly living with little-to-mild levels of aging symptoms, whereas their severity was correlated with age. PMID:27068128

  8. A sex-specific transcription factor controls male identity in a simultaneous hermaphrodite.

    PubMed

    Chong, Tracy; Collins, James J; Brubacher, John L; Zarkower, David; Newmark, Phillip A

    2013-01-01

    Evolutionary transitions between hermaphroditic and dioecious reproductive states are found in many groups of animals. To understand such transitions, it is important to characterize diverse modes of sex determination utilized by metazoans. Currently, little is known about how simultaneous hermaphrodites specify and maintain male and female organs in a single individual. Here we show that a sex-specific gene, Smed-dmd-1 encoding a predicted doublesex/male-abnormal-3 (DM) domain transcription factor, is required for specification of male germ cells in a simultaneous hermaphrodite, the planarian Schmidtea mediterranea. dmd-1 has a male-specific role in the maintenance and regeneration of the testes and male accessory reproductive organs. In addition, a homologue of dmd-1 exhibits male-specific expression in Schistosoma mansoni, a derived, dioecious flatworm. These results demonstrate conservation of the role of DM domain genes in sexual development in lophotrochozoans and suggest one means by which modulation of sex-specific pathways can drive the transition from hermaphroditism to dioecy. PMID:23652002

  9. 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

  10. 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

  11. TBBPA chronic exposure produces sex-specific neurobehavioral and social interaction changes in adult zebrafish.

    PubMed

    Chen, Jiangfei; Tanguay, Robert L; Simonich, Michael; Nie, Shangfei; Zhao, Yuxin; Li, Lelin; Bai, Chenglian; Dong, Qiaoxiang; Huang, Changjiang; Lin, Kuangfei

    2016-01-01

    The toxicity of tetrabromobisphenol A (TBBPA) has been extensively studied because of its high production volume. TBBPA is toxic to aquatic fish based on acute high concentration exposure tests, and few studies have assessed the behavioral effects of low concentration chronic TBBPA exposures in aquatic organisms. The present study defined the developmental and neurobehavioral effects associated with exposure of zebrafish to 0, 5 and 50nM TBBPA during 1-120days post-fertilization (dpf) following by detoxification for four months before the behaviors assessment. These low concentration TBBPA exposures were not associated with malformations and did not alter sex ratio, but resulted in reduced zebrafish body weight and length. Adult behavioral assays indicated that TBBPA exposed males had significantly higher average swim speeds and spent significantly more time in high speed darting mode and less time in medium cruising mode compared to control males. In an adult photomotor response assay, TBBPA exposure was associated with hyperactivity in male fish. Female zebrafish responses in these assays followed a similar trend, but the magnitude of TBBPA effects was generally smaller than in males. Social interaction evaluated using a mirror attack test showed that 50nM TBBPA exposed males had heightened aggression. Females exposed to 50nM TBBPA spent more time in the vicinity of the mirror, but did not show increased aggression toward the mirror compared to unexposed control fish. Overall, the hyperactivity and social behavior deficits ascribed here to chronic TBBPA exposure was most profound in males. Our findings indicate that TBBPA can cause developmental and neurobehavioral deficits, and may pose significant health risk to humans. PMID:27221227

  12. 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

  13. 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

  14. 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

  15. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pear psylla, Cacopsylla pyricola (Förster) (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...

  17. Sex hormones, sexual activity and plasma anticonvulsant levels in male epileptics.

    PubMed Central

    Toone, B K; Wheeler, M; Nanjee, M; Fenwick, P; Grant, R

    1983-01-01

    Testosterone, LH, FSH, PRL, and sex hormone binding globulin (SHBG) were measured in 72 male epileptic patients on chronic anticonvulsant drug regimes. Sexual activity was estimated and plasma anticonvulsants measured. Total testosterone (TT), LH, FSH, PRL, and SHBG were increased; free testosterone (FT) was decreased. Sexual activity appeared diminished particularly in relation to reduced FT. PMID:6413659

  18. 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…

  19. Assisted reproduction in a cohort of same-sex male couples and single men.

    PubMed

    Grover, Stephanie A; Shmorgun, Ziva; Moskovtsev, Sergey I; Baratz, Ari; Librach, Clifford L

    2013-08-01

    To date, there is limited published data on same-sex male couples and single men using assisted reproduction treatment to build their families. The objective of this retrospective study was to better understand treatment considerations and outcomes for this population when using assisted reproduction treatment. A total of 37 same-sex male couples and eight single men (seven homosexual and one heterosexual) who attended the CReATe Fertility Centre for assisted reproduction services were studied. There was a 21-fold increase in the number of same-sex male couples and single men undergoing assisted reproduction treatment since 2003. The mean age was 46years (24-58). Twenty-eight couples (76%) chose to use spermatozoa from both partners to fertilize their donated oocytes. Most men (32 same-sex male couples and seven single men; 87%) obtained oocytes from an anonymous donor, whereas five couples and one single man (13%) had a known donor. Anonymous donors who were open to be contacted by the child after the age of 18 were selected by 67% of patients. Of all 25 deliveries, eight (32%) were sets of twins. All of the twins were half genetic siblings. PMID:23768615

  20. 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…

  1. 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

  2. Testosterone influences spatial strategy preferences among adult male rats

    PubMed Central

    Spritzer, Mark D.; Fox, Elliott C.; Larsen, Gregory D.; Batson, Christopher G.; Wagner, Benjamin A.; Maher, Jack

    2013-01-01

    Males outperform females on some spatial tasks, and this may be partially due to the effects of sex steroids on spatial strategy preferences. Previous work with rodents indicates that low estradiol levels bias females toward a striatum-dependent response strategy, whereas high estradiol levels bias them toward a hippocampus-dependent place strategy. We tested whether testosterone influenced the strategy preferences in male rats. All subjects were castrated and assigned to one of three daily injection doses of testosterone (0.125, 0.250, or 0.500 mg/rat) or a control group that received daily injections of the drug vehicle. Three different maze protocols were used to determine rats’ strategy preferences. A low dose of testosterone (0.125 mg) biased males toward a motor-response strategy on a T-maze task. In a water maze task in which the platform itself could be used intermittently as a visual cue, a low testosterone dose (0.125 mg) caused a significant increase in the use of a cued-response strategy relative to control males. Results from this second experiment also indicated that males receiving a high dose of testosterone (0.500 mg) were biased toward a place strategy. A third experiment indicated that testosterone dose did not have a strong influence on the ability of rats to use a nearby visual cue (floating ball) in the water maze. For this experiment, all groups seemed to use a combination of place and cued-response strategies. Overall, the results indicate that the effects of testosterone on spatial strategy preference are dose dependent and task dependent. PMID:23597827

  3. Adverse Childhood Experiences in the Lives of Male Sex Offenders: Implications for Trauma-Informed Care.

    PubMed

    Levenson, Jill S; Willis, Gwenda M; Prescott, David S

    2016-06-01

    This study explored the prevalence of childhood trauma in a sample of male sexual offenders (N = 679) using the Adverse Childhood Experience (ACE) scale. Compared with males in the general population, sex offenders had more than 3 times the odds of child sexual abuse (CSA), nearly twice the odds of physical abuse, 13 times the odds of verbal abuse, and more than 4 times the odds of emotional neglect and coming from a broken home. Less than 16% endorsed zero ACEs and nearly half endorsed four or more. Multiple maltreatments often co-occurred with other types of household dysfunction, suggesting that many sex offenders were raised within a disordered social environment. Higher ACE scores were associated with higher risk scores. By enhancing our understanding of the frequency and correlates of early adverse experiences, we can better devise trauma-informed interventions that respond to the clinical needs of sex offender clients. PMID:24872347

  4. Dietary glucose regulates yeast consumption in adult Drosophila males.

    PubMed

    Lebreton, Sébastien; Witzgall, Peter; Olsson, Marie; Becher, Paul G

    2014-01-01

    The adjustment of feeding behavior in response to hunger and satiety contributes to homeostatic regulation in animals. The fruit fly Drosophila melanogaster feeds on yeasts growing on overripe fruit, providing nutrients required for adult survival, reproduction and larval growth. Here, we present data on how the nutritional value of food affects subsequent yeast consumption in Drosophila adult males. After a period of starvation, flies showed intensive yeast consumption. In comparison, flies stopped feeding after having access to a nutritive cornmeal diet. Interestingly, dietary glucose was equally efficient as the complex cornmeal diet. In contrast, flies fed with sucralose, a non-metabolizable sweetener, behaved as if they were starved. The adipokinetic hormone and insulin-like peptides regulate metabolic processes in insects. We did not find any effect of the adipokinetic hormone pathway on this modulation. Instead, the insulin pathway was involved in these changes. Flies lacking the insulin receptor (InR) did not respond to nutrient deprivation by increasing yeast consumption. Together these results show the importance of insulin in the regulation of yeast consumption in response to starvation in adult D. melanogaster males. PMID:25566097

  5. Dietary glucose regulates yeast consumption in adult Drosophila males

    PubMed Central

    Lebreton, Sébastien; Witzgall, Peter; Olsson, Marie; Becher, Paul G.

    2014-01-01

    The adjustment of feeding behavior in response to hunger and satiety contributes to homeostatic regulation in animals. The fruit fly Drosophila melanogaster feeds on yeasts growing on overripe fruit, providing nutrients required for adult survival, reproduction and larval growth. Here, we present data on how the nutritional value of food affects subsequent yeast consumption in Drosophila adult males. After a period of starvation, flies showed intensive yeast consumption. In comparison, flies stopped feeding after having access to a nutritive cornmeal diet. Interestingly, dietary glucose was equally efficient as the complex cornmeal diet. In contrast, flies fed with sucralose, a non-metabolizable sweetener, behaved as if they were starved. The adipokinetic hormone and insulin-like peptides regulate metabolic processes in insects. We did not find any effect of the adipokinetic hormone pathway on this modulation. Instead, the insulin pathway was involved in these changes. Flies lacking the insulin receptor (InR) did not respond to nutrient deprivation by increasing yeast consumption. Together these results show the importance of insulin in the regulation of yeast consumption in response to starvation in adult D. melanogaster males. PMID:25566097

  6. Prevalence of childhood physical abuse in adult male veteran alcoholics.

    PubMed

    Schaefer, M R; Sobieraj, K; Hollyfield, R L

    1988-01-01

    Although past research has identified psychological and behavioral consequences for adults who were abused as children, few studies have examined the incidence and consequences of childhood physical abuse among adult alcoholics. The purpose of this study was to assess the prevalence of a childhood history of physical abuse in adult male alcoholics and to determine what differences may exist in the psychological profile and patterns of alcohol abuse in abused and nonabused alcoholics. The study sample was comprised of 100 male alcoholic inpatients from the alcoholism treatment unit at a metropolitan Veterans Administration hospital. Subjects were administered a self-report devised by the authors to assess a history of childhood physical abuse, the Michigan Alcoholism Screening Test (MAST), the Severity of Alcohol Dependence Questionnaire (SADQ), and the Symptom Checklist-90-Revised (SCL-90-R). Findings indicated that approximately one-third of the alcoholics were physically abused as children. Abused alcoholics reported having more severe psychological symptoms and distress than their nonabused counterparts, although they did not differ on the onset, severity, or treatment history for alcohol dependency. PMID:3260808

  7. 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

  8. Dietary and sex-specific factors regulate hypothalamic neurogenesis in young adult mice

    PubMed Central

    Lee, Daniel A.; Yoo, Sooyeon; Pak, Thomas; Salvatierra, Juan; Velarde, Esteban; Aja, Susan; Blackshaw, Seth

    2014-01-01

    The hypothalamus is the central regulator of a broad range of homeostatic and instinctive physiological processes, such as the sleep-wake cycle, food intake, and sexually dimorphic behaviors. These behaviors can be modified by various environmental and physiological cues, although the molecular and cellular mechanisms that mediate these effects remain poorly understood. Recently, it has become clear that both the juvenile and adult hypothalamus exhibit ongoing neurogenesis, which serve to modify homeostatic neural circuitry. In this report, we share new findings on the contributions of sex-specific and dietary factors to regulating neurogenesis in the hypothalamic mediobasal hypothalamus, a recently identified neurogenic niche. We report that high fat diet (HFD) selectively activates neurogenesis in the median eminence (ME) of young adult female but not male mice, and that focal irradiation of the ME in HFD-fed mice reduces weight gain in females but not males. These results suggest that some physiological effects of high fat diet are mediated by the stimulation of ME neurogenesis in a sexually dimorphic manner. We discuss these results in the context of recent advances in understanding the cellular and molecular mechanisms that regulate neurogenesis in postnatal and adult hypothalamus. PMID:24982613

  9. Prenatal cocaine exposure increases heart susceptibility to ischaemia–reperfusion injury in adult male but not female rats

    PubMed Central

    Bae, Soochan; Gilbert, Raymond D; Ducsay, Charles A; Zhang, Lubo

    2005-01-01

    The present study tested the hypothesis that prenatal cocaine exposure differentially regulates heart susceptibility to ischaemia–reperfusion (I/R) injury in adult offspring male and female rats. Pregnant rats were administered intraperitoneally either saline or cocaine (15 mg kg−1) twice daily from day 15 to day 21 of gestational age. There were no differences in maternal weight gain and birth weight between the two groups. Hearts were isolated from 2-month-old male and female offspring and were subjected to I/R (25 min/60 min) in a Langendorff preparation. Preischaemic values of left ventricular (LV) function were the same between the saline control and cocaine-treated hearts for both male and female rats. Prenatal cocaine exposure significantly increased I/R-induced myocardial apoptosis and infarct size, and significantly attenuated the postischaemic recovery of LV function in adult male offspring. In contrast, cocaine did not affect I/R-induced injury and postischaemic recovery of LV function in the female hearts. There was a significant decrease in PKCɛ and phospho-PKCɛ levels in LV in the male, but not female, offspring exposed to cocaine before birth. These results suggest that prenatal cocaine exposure causes a sex-specific increase in heart susceptibility to I/R injury in adult male offspring, and the decreased PKCɛ gene expression in the male heart may play an important role. PMID:15677681

  10. Demographic response of black bears at Cold Lake, Alberta, to the removal of adult males

    USGS Publications Warehouse

    Sargeant, G.A.; Ruff, R.L.

    2001-01-01

    Previous reports described an increase in population density following the removal of 23 adult male black bears (Ursus americanus) from a 218-km2 study area near Cold Lake, Alberta (the CLSA). This finding plays a central role in continuing debates over population regulation in bears, but has recently been criticized because density estimates were based on assumptions that were not met. Moreover, subsequent discussion has been predicated on conjecture that human exploitation had minimal influence on population dynamics. Our reanalysis supports previous descriptions of trends in bear density at Cold Lake. However, survival records revealed heavier exploitation than previously suspected. An underlying assumption of previous interpretationsCthat the Cold Lake bear population was naturally regulated near carrying capacityCno longer seems reasonable. Adult males deterred bears in other sex-age groups from using the CLSA; however, we found no evidence that birth or death rates were affected. The observed increase in local density should not be construed as a density-dependent response. Abrupt changes in local density might not have occurred if males had been removed from a larger area encompassing the CLSA

  11. Stigma, social inequality, and HIV risk disclosure among Dominican male sex workers☆

    PubMed Central

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

    2010-01-01

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

  12. Synergistic Disruption of External Male Sex Organ Development by a Mixture of Four Antiandrogens

    PubMed Central

    Christiansen, Sofie; Scholze, Martin; Dalgaard, Majken; Vinggaard, Anne Marie; Axelstad, Marta; Kortenkamp, Andreas; Hass, Ulla

    2009-01-01

    Background By disrupting the action of androgens during gestation, certain chemicals present in food, consumer products, and the environment can induce irreversible demasculinization and malformations of sex organs among male offspring. However, the consequences of simultaneous exposure to such chemicals are not well described, especially when they exert their actions by differing molecular mechanisms. Objectives To fill this gap, we investigated the effects of mixtures of a widely used plasticizer, di(2-ethylhexyl) phthalate (DEHP); two fungicides present in food, vinclozolin and prochloraz; and a pharmaceutical, finasteride, on landmarks of male sexual development in the rat, including changes in anogenital distance (AGD), retained nipples, sex organ weights, and malformations of genitalia. These chemicals were chosen because they disrupt androgen action with differing mechanisms of action. Results Strikingly, the effect of combined exposure to the selected chemicals on malformations of external sex organs was synergistic, and the observed responses were greater than would be predicted from the toxicities of the individual chemicals. In relation to other hallmarks of disrupted male sexual development, including changes in AGD, retained nipples, and sex organ weights, the combined effects were dose additive. When the four chemicals were combined at doses equal to no observed adverse effect levels estimated for nipple retention, significant reductions in AGD were observed in male offspring. Conclusions Because unhindered androgen action is essential for human male development in fetal life, these findings are highly relevant to human risk assessment. Evaluations that ignore the possibility of combination effects may lead to considerable underestimations of risks associated with exposures to chemicals that disrupt male sexual differentiation. PMID:20049201

  13. Cognitive Distortions and Blame Attribution in Sex Offenders against Adults and Children.

    ERIC Educational Resources Information Center

    Blumenthal, Stephen; Gudjonsson, Gisli; Burns, Jan

    1999-01-01

    This study compared sex offenders against children and adults on measures of cognitive distortions relating to sex with children and rape and a measure of blame attribution. Child sexual offenders endorsed more cognitive distortions relating to sex with children and reported more guilt-feeling attributions. (Author/DB)

  14. 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

  15. Sex Differences and Effects of Prenatal Exposure to Excess Testosterone on Ventral Tegmental Area Dopamine Neurons in Adult Sheep

    PubMed Central

    Brown, Erinna C. Z.; Steadman, Casey J.; Lee, Theresa M.; Padmanabhan, Vasantha; Lehman, Michael N.; Coolen, Lique M.

    2015-01-01

    Prenatal testosterone (T) excess in sheep results in a wide array of reproductive neuroendocrine deficits and alterations in motivated behavior. The ventral tegmental area (VTA) plays a critical role in reward and motivated behaviors and is hypothesized to be targeted by prenatal T. Here we report a sex difference in the number VTA dopamine cells in the adult sheep with higher numbers of tyrosine hydroxylase (TH)-immunoreactive cells in males than females. Moreover, prenatal exposure to excess T during either gestational days 30–90 or 60–90 resulted in increased numbers of VTA TH- immunoreactive cells in adult ewes compared to control females. Stereological analysis confirmed significantly greater numbers of neurons in the VTA of males and prenatal T-treated ewes, which was primarily accounted for by greater numbers of TH-immunoreactive cells. In addition, immunoreactivity for TH in the cells was denser in males and prenatal T-treated females, suggesting that sex differences and prenatal exposure to excess T affects both numbers of cells expressing TH as well as the protein levels with dopamine cells. Sex differences were also noted in numbers of TH-immunoreactive cells in the substantia nigra, with more cells in males than females. However, prenatal exposure to excess T did not affect numbers of TH-immunoreactive cells in the substantia nigra, suggesting that this sex difference is organized independently from prenatal actions of T. Together, these results demonstrate sex differences in the sheep VTA dopamine system which are mimicked by prenatal treatment with excess T. PMID:25784297

  16. A Review of "Older, Wiser, Sexually Smarter: 30 Sex Ed Lessons for Adults Only"

    ERIC Educational Resources Information Center

    Garrity, Joan Mogul

    2010-01-01

    While virtually all sex ed curricula are designed to be used with children, teens and young adults, "Older, Wiser, Sexually Smarter: 30 Sex Ed Lessons for Adults Only" ([C] 2009, Planned Parenthood of Greater Northern New Jersey) offers lessons to help participants fully embrace the possibility of sexual pleasure and intimacy from mid-life through…

  17. 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

  18. Antenatal glucocorticoid treatment alters Na+ uptake in renal proximal tubule cells from adult offspring in a sex-specific manner

    PubMed Central

    Su, Yixin; Bi, Jianli; Figueroa, Jorge; Chappell, Mark; Rose, James C.

    2015-01-01

    We have shown a sex-specific effect of fetal programming on Na+ excretion in adult sheep. The site of this effect in the kidney is unknown. Therefore, we tested the hypothesis that renal proximal tubule cells (RPTCs) from adult male sheep exposed to betamethasone (Beta) before birth have greater Na+ uptake than do RPTCs from vehicle-exposed male sheep and that RPTCs from female sheep similarly exposed are not influenced by antenatal Beta. In isolated RPTCs from 1- to 1.5-yr-old male and female sheep, we measured Na+ uptake under basal conditions and after stimulation with ANG II. To gain insight into the mechanisms involved, we also measured nitric oxide (NO) levels, ANG II receptor mRNA levels, and expression of Na+/H+ exchanger 3. Basal Na+ uptake increased more in cells from Beta-exposed male sheep than in cells from vehicle-exposed male sheep (400% vs. 300%, P < 0.00001). ANG II-stimulated Na+ uptake was also greater in cells from Beta-exposed males. Beta exposure did not increase Na+ uptake by RPTCs from female sheep. NO production was suppressed more by ANG II in RPTCs from Beta-exposed males than in RPTCs from either vehicle-exposed male or female sheep. Our data suggest that one site of the sex-specific effect of Beta-induced fetal programming in the kidney is the RPTC and that the enhanced Na+ uptake induced by antenatal Beta in male RPTCs may be related to the suppression of NO in these cells. PMID:25834069

  19. Photometric facial analysis of the Igbo Nigerian adult male

    PubMed Central

    Ukoha, Ukoha Ukoha; Udemezue, Onochie Okwudili; Oranusi, Chidi Kingsley; Asomugha, Azuoma Lasbrey; Dimkpa, Uchechukwu; Nzeukwu, Lynda Chinenye

    2012-01-01

    Background: A carefully performed facial analysis can serve as a strong foundation for successful facial reconstructive and plastic surgeries, rhinoplasty or orthodontics. Aim: The purpose of this study is to determine the facial features and qualities of the Igbo Nigerian adult male using photometry. Materials and Methods: One hundred and twenty subjects aged between 18 and 28 years were studied at the Anambra State University, Uli, Nigeria. The frontal and right lateral view photographs of their faces were taken and traced out on tracing papers. On these, two vertical distances, nasion to subnasal and subnasale to menton, and four angles, nasofrontal (NF), nasofacial, nasomental (NM) and mentocervical, were measured. Results: The result showed that the Igbo Nigerian adult male had a middle face that was shorter than the lower one (41.76% vs.58.24%), a moderate glabella (NF=133.97°), a projected nose (NM=38.68°) and a less prominent chin (NM=125.87°). Conclusion: This study is very important in medical practice as it can be used to compare the pre- and post-operative results of plastic surgery and other related surgeries of the face. PMID:23661886

  20. Past experiences of adults with disorders of sex development.

    PubMed

    Audí, Laura

    2014-01-01

    When a human being born with any disorder/difference of sex development (DSD) reaches adulthood, the experience lived may be quite varied, depending partly on the age at diagnosis, the underlying cause, physical and health involvement, family circle, health system care received, societal culture and psychological ability to face the process, etc. As affected persons may suffer not only from diverse types of physical differences, but also difficulties in adapting their lives to the most common social mores, international consensus has long advocated a pluridisciplinary care involving different medical specialities. Although healthcare systems have progressively improved, the physical and psychological experiences of these adults may often have been stressful or traumatic, partly due to the 'rarity or low frequency' of their condition, and also to the fact that the person's sexual life is involved. The creation of support groups by affected individuals and their activities have proved extremely rewarding by improving individual well-being and pushing healthcare systems towards higher standards. In this chapter, we present the work of a patient support group in Spain (objectives, activities and opinions) and reflect present views and past experiences of a number of its adult members. PMID:25247651

  1. 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

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

    PubMed

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

    2014-11-18

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

  3. 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

  4. 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

  5. Substance Use among Male Sex Workers in Vietnam: Prevalence, Onset, and Interactions with Sexual Risk

    PubMed Central

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

    2014-01-01

    Background HIV research in Vietnam has focused primarily on its large heroin injector population. Data on men who have sex with men [MSM], particularly the large and growing population of men who exchange sex for money or other material rewards, male sex workers [MSWs], is very limited. Methods Data derive from a cross-sectional study of MSW, age 16-35, recruited using community sampling methods in three cities in 2010-2011, including Hanoi, Ho Chi Minh City [HCMC], and Nha Trang City (n=710). Assessments included demographic characteristics, substance use, sexual risk, and use of health services. A series of “event” questions were used to assess the influence of alcohol and drugs on sexual risk. Results Both tobacco and alcohol are initiated at a young age and most participants currently use both substances overall across all three cities. While alcohol and tobacco use precede the initiation of sex work, stimulant and opiate use are initiated following the initiation of sex work. There was substantial overlap between substance use and sexual risk, and this overlap was strongest in sexual events involving male and female elective partners rather than sex work clients. Conclusion Although rates of HIV infection in this group are low, this may be an artifact of the young age of the sample. High rates of drug use, including alcohol, tobacco and illicit drugs, coupled with high rates of ulcerative STIs such as HPV, suggest the potential for rapid amplification of STI/HIV risk among MSW and their complex sex partnering networks. PMID:25488636

  6. 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

  7. 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

  8. HIV and STI Prevalence and Risk Factors Among Male Sex Workers and Other Men Who Have Sex With Men in Nairobi, Kenya

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2015-01-01

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

  10. 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

  11. 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

  12. Characteristics of sex partners and sexual partnership correlates of inconsistent condom use among male injection drug users in India.

    PubMed

    Tun, Waimar; Bhattacharya, Aruna; Apicella, Louis; Shasikumar Singh, Yumnam; Lewis, Dean

    2014-07-01

    Previous studies have established the risky behaviors of IDUs in India, and that IDUs are sexually active; however, there is a need to better understand the nature of sexual partnerships of IDUs. A total of 783 (Delhi) and 766 (Imphal) male IDUs were recruited into the study through respondent-driven sampling. We examined characteristics of sex partners of male IDUs and individual and sexual partnership characteristics associated with unprotected sex in Delhi and Imphal. While 16.8% of sexual partnerships in Delhi were male-to-male, there were almost no male-to-male partnerships in Imphal. The majority of partners of male IDUs in Delhi (82.5%) and Imphal (92.3%) do not inject drugs, with the exception of male partners of male IDUs in Delhi. Commercial partners (females: 58.3%; males: 71.3%) were the most common type of sex partners of male IDUs in Delhi, while regular partners (65.2%) were the most common type of sex partners in Imphal. In Delhi, characteristics of sex partners significantly associated with unprotected sex were being male/transgender (AOR 2.2; 95% CI: 1.2-4.0), being a regular (AOR 5.1; 95% CI: 2.8-9.4) or non-regular partner (AOR 2.7; 95% CI: 1.7- 4.5), and sharing needles/syringes with the index IDU (AOR 2.8; 95% CI: 1.4-5.3). In Imphal, partner characteristics associated with unprotected sex were being a regular (AOR 10.1; 95% CI: 41-25.1) or non-regular partner (AOR 3.4; 95% CI: 1.5-7.6), and living outside of town or state (AOR 3.3; 95% CI: 1.2-9.6). Enhanced understanding of disassortative sexual mixing and context of unprotected sex within sexual partnerships may enhance sexual risk reduction interventions for IDUs. PMID:25427360

  13. Risk factors for adult male criminality in Colombia.

    PubMed

    Klevens, Joanne; Roca, Juanita; Restrepo, Ofelia; Martinez, Adriana

    2001-01-01

    OBJECTIVES: This study sought to establish, in Colombia, the importance of factors alleged to be causes or correlates of adult criminality according to the published literature from other countries. METHODS: A comparison was made of arrested male offenders from ages 18 to 30 (n = 223) and similar community controls (n = 222) selected from five cities in Colombia as to their family background, exposure to abuse, family stressors, perceived care and history of childhood disruptive behaviour problems. RESULTS: Compared with neighbourhood controls from similar social classes, offenders were significantly more likely to report having had parents with less education, a mother under the age of 18 or over the age of 35 at time of birth, family members involved in crime, experiencing extreme economic deprivation, parental absence, family conflict, severe punishments, physical abuse, and maternal unavailability, rejection and lack of supervision. Prevalence of childhood disruptive behaviour problems was similar among offenders and controls. These findings appear to be independent of economic status, family size or type, birth order, or primary caregiver. Although the independent contribution of most of these factors is small, once all others have been controlled for, their cumulative effect is strong. CONCLUSIONS: The findings obtained in this Latin American setting do not support the generalized view that adult antisocial behaviour is necessarily preceded by a history of childhood behaviour problems. However, they do add evidence for the importance of family factors in the risk for adult criminality. PMID:12048531

  14. 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

  15. Insights into the preservation of the homomorphic sex-determining chromosome of Aedes aegypti from the discovery of a male-biased gene tightly linked to the M-locus.

    PubMed

    Hall, Andrew Brantley; Timoshevskiy, Vladimir A; Sharakhova, Maria V; Jiang, Xiaofang; Basu, Sanjay; Anderson, Michelle A E; Hu, Wanqi; Sharakhov, Igor V; Adelman, Zach N; Tu, Zhijian

    2014-01-01

    The preservation of a homomorphic sex-determining chromosome in some organisms without transformation into a heteromorphic sex chromosome is a long-standing enigma in evolutionary biology. A dominant sex-determining locus (or M-locus) in an undifferentiated homomorphic chromosome confers the male phenotype in the yellow fever mosquito Aedes aegypti. Genetic evidence suggests that the M-locus is in a nonrecombining region. However, the molecular nature of the M-locus has not been characterized. Using a recently developed approach based on Illumina sequencing of male and female genomic DNA, we identified a novel gene, myo-sex, that is present almost exclusively in the male genome but can sporadically be found in the female genome due to recombination. For simplicity, we define sequences that are primarily found in the male genome as male-biased. Fluorescence in situ hybridization (FISH) on A. aegypti chromosomes demonstrated that the myo-sex probe localized to region 1q21, the established location of the M-locus. Myo-sex is a duplicated myosin heavy chain gene that is highly expressed in the pupa and adult male. Myo-sex shares 83% nucleotide identity and 97% amino acid identity with its closest autosomal paralog, consistent with ancient duplication followed by strong purifying selection. Compared with males, myo-sex is expressed at very low levels in the females that acquired it, indicating that myo-sex may be sexually antagonistic. This study establishes a framework to discover male-biased sequences within a homomorphic sex-determining chromosome and offers new insights into the evolutionary forces that have impeded the expansion of the nonrecombining M-locus in A. aegypti. PMID:24398378

  16. Insights into the Preservation of the Homomorphic Sex-Determining Chromosome of Aedes aegypti from the Discovery of a Male-Biased Gene Tightly Linked to the M-Locus

    PubMed Central

    Hall, Andrew Brantley; Timoshevskiy, Vladimir A.; Sharakhova, Maria V.; Jiang, Xiaofang; Basu, Sanjay; Anderson, Michelle A.E.; Hu, Wanqi; Sharakhov, Igor V.; Adelman, Zach N.; Tu, Zhijian

    2014-01-01

    The preservation of a homomorphic sex-determining chromosome in some organisms without transformation into a heteromorphic sex chromosome is a long-standing enigma in evolutionary biology. A dominant sex-determining locus (or M-locus) in an undifferentiated homomorphic chromosome confers the male phenotype in the yellow fever mosquito Aedes aegypti. Genetic evidence suggests that the M-locus is in a nonrecombining region. However, the molecular nature of the M-locus has not been characterized. Using a recently developed approach based on Illumina sequencing of male and female genomic DNA, we identified a novel gene, myo-sex, that is present almost exclusively in the male genome but can sporadically be found in the female genome due to recombination. For simplicity, we define sequences that are primarily found in the male genome as male-biased. Fluorescence in situ hybridization (FISH) on A. aegypti chromosomes demonstrated that the myo-sex probe localized to region 1q21, the established location of the M-locus. Myo-sex is a duplicated myosin heavy chain gene that is highly expressed in the pupa and adult male. Myo-sex shares 83% nucleotide identity and 97% amino acid identity with its closest autosomal paralog, consistent with ancient duplication followed by strong purifying selection. Compared with males, myo-sex is expressed at very low levels in the females that acquired it, indicating that myo-sex may be sexually antagonistic. This study establishes a framework to discover male-biased sequences within a homomorphic sex-determining chromosome and offers new insights into the evolutionary forces that have impeded the expansion of the nonrecombining M-locus in A. aegypti. PMID:24398378

  17. Adult female hamsters avoid interspecific mating after exposure to heterospecific males

    PubMed Central

    delBarco-Trillo, Javier; McPhee, M. E.; Johnston, Robert E.

    2010-01-01

    When females mate with a heterospecific male, they do not usually produce viable offspring. Thus, there is a selective pressure for females to avoid interspecific mating. In many species, females innately avoid heterospecific males; females can also imprint on their parents to avoid later sexual interactions with heterospecific males. However, it was previously unknown whether adult females can learn to discriminate against heterospecific males. We tested the hypothesis that adult females previously unable to avoid interspecific mating learn to avoid such mating after being exposed to heterospecific males. Syrian hamster (Mesocricetus auratus) females not previously exposed to Turkish hamster (Mesocricetus brandti) males can discriminate between odors of conspecific and heterospecific males, but they mate with either type of male. However, when we exposed adult females to both a conspecific male and a heterospecific male through wire-mesh barriers for 8 days, and then paired them sequentially with the two males, females were more receptive to conspecific males and more aggressive to heterospecific males. When females were paired with the heterospecific male first and the conspecific male second, no female was receptive and all were aggressive to heterospecific males. When females were paired with the conspecific male first, only 43% of females were then aggressive toward the heterospecific male. That is, interactions with conspecific males may decrease a female’s ability to properly avoid heterospecific males. Our study clearly shows for the first time that females can learn during adulthood to avoid interspecific mating just by being exposed to stimuli from heterospecific males. PMID:20676390

  18. Quantitative Trait Locus Analysis of Mating Behavior and Male Sex Pheromones in Nasonia Wasps.

    PubMed

    Diao, Wenwen; Mousset, Mathilde; Horsburgh, Gavin J; Vermeulen, Cornelis J; Johannes, Frank; van de Zande, Louis; Ritchie, Michael G; Schmitt, Thomas; Beukeboom, Leo W

    2016-01-01

    A major focus in speciation genetics is to identify the chromosomal regions and genes that reduce hybridization and gene flow. We investigated the genetic architecture of mating behavior in the parasitoid wasp species pair Nasonia giraulti and Nasonia oneida that exhibit strong prezygotic isolation. Behavioral analysis showed that N. oneida females had consistently higher latency times, and broke off the mating sequence more often in the mounting stage when confronted with N. giraulti males compared with males of their own species. N. oneida males produce a lower quantity of the long-range male sex pheromone (4R,5S)-5-hydroxy-4-decanolide (RS-HDL). Crosses between the two species yielded hybrid males with various pheromone quantities, and these males were used in mating trials with females of either species to measure female mate discrimination rates. A quantitative trait locus (QTL) analysis involving 475 recombinant hybrid males (F2), 2148 reciprocally backcrossed females (F3), and a linkage map of 52 equally spaced neutral single nucleotide polymorphism (SNP) markers plus SNPs in 40 candidate mating behavior genes revealed four QTL for male pheromone amount, depending on partner species. Our results demonstrate that the RS-HDL pheromone plays a role in the mating system of N. giraulti and N. oneida, but also that additional communication cues are involved in mate choice. No QTL were found for female mate discrimination, which points at a polygenic architecture of female choice with strong environmental influences. PMID:27172207

  19. 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

  20. Quantitative Trait Locus Analysis of Mating Behavior and Male Sex Pheromones in Nasonia Wasps

    PubMed Central

    Diao, Wenwen; Mousset, Mathilde; Horsburgh, Gavin J.; Vermeulen, Cornelis J.; Johannes, Frank; van de Zande, Louis; Ritchie, Michael G.; Schmitt, Thomas; Beukeboom, Leo W.

    2016-01-01

    A major focus in speciation genetics is to identify the chromosomal regions and genes that reduce hybridization and gene flow. We investigated the genetic architecture of mating behavior in the parasitoid wasp species pair Nasonia giraulti and Nasonia oneida that exhibit strong prezygotic isolation. Behavioral analysis showed that N. oneida females had consistently higher latency times, and broke off the mating sequence more often in the mounting stage when confronted with N. giraulti males compared with males of their own species. N. oneida males produce a lower quantity of the long-range male sex pheromone (4R,5S)-5-hydroxy-4-decanolide (RS-HDL). Crosses between the two species yielded hybrid males with various pheromone quantities, and these males were used in mating trials with females of either species to measure female mate discrimination rates. A quantitative trait locus (QTL) analysis involving 475 recombinant hybrid males (F2), 2148 reciprocally backcrossed females (F3), and a linkage map of 52 equally spaced neutral single nucleotide polymorphism (SNP) markers plus SNPs in 40 candidate mating behavior genes revealed four QTL for male pheromone amount, depending on partner species. Our results demonstrate that the RS-HDL pheromone plays a role in the mating system of N. giraulti and N. oneida, but also that additional communication cues are involved in mate choice. No QTL were found for female mate discrimination, which points at a polygenic architecture of female choice with strong environmental influences. PMID:27172207

  1. 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 now serving 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

  2. Acetylcholinesterase activity in the sexually dimorphic area of the gerbil brain: sex differences and influences of adult gonadal steroids.

    PubMed

    Commins, D; Yahr, P

    1984-03-20

    The morphology of the medial preoptic area-anterior hypothalamus (MPOA-AH) of gerbils is sexually dimorphic and influenced by adult gonadal hormones. This research shows that the distribution of (MPOA-AH) cells that synthesize acetylcholinesterase (AChE) and the activity of AChE within the MPOA-AH are also sexually dimorphic and hormone sensitive. Adult male and female gerbils were gonadectomized, gonadectomized and implanted subcutaneously with testosterone (T), or sham operated 4-8 weeks before sacrifice. Coronal sections through the sexually dimorphic area (SDA) of the MPOA-AH were stained for AChE. Planimeter measurements of camera lucida drawings showed that the total volume of the SDA is similar in the two sexes, but the proportion of the SDA that stains darkly and/or stands out clearly from the surround (dark volume) is larger in males. Optical density readings also indicated that AChE staining is darker in the male SDA. Gonadectomy decreases staining intensity in both sexes and reduces total SDA volume. Dark volume decreases more than 50%. Testosterone treatment reverses all effects of gonadectomy, although hormonal influences are smaller in females than in males. There were no sex differences or hormonal influences on AChE staining lateral to the SDA. The pars compacta of the male SDA was essentially devoid of AChE, indicating that this cell group is distinct from the rest of the SDA. It also shrinks after castration unless the males receive T. Histochemical changes in the SDA may be related to hormonal control of scent marking, a form of communication in this species. PMID:6715576

  3. Sex steroid and prolactin profiles in male American black bears (Ursus americanus) during denning.

    PubMed

    Tsubota, T; Garshelis, D L; Nelson, R A; Bahr, J M

    1999-01-01

    Serum sex steroid and prolactin profiles were examined in the male American black bear, Ursus americanus during denning. Sera collected in December and the following March from 8 denning male black bears in Minnesota, U.S.A. were assayed for testosterone, estradiol-17 beta and prolactin. Eight bears were confirmed to be the denning mode based on a serum urea to creatinine ratio less than 10. Serum testosterone concentrations tended to increase from December to the subsequent March whereas serum estradiol-17 beta concentrations tended to decrease during this period. There were few changes in serum prolactin concentrations between December and March. These findings suggest that spermatogenesis and testicular steroidogenesis initiated during denning may be influenced by changes in serum sex steroid concentrations in the American black bear. PMID:10027172

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

    PubMed Central

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

    2015-01-01

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

  5. 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

  6. Race and Sex Differences in Small-Molecule Metabolites and Metabolic Hormones in Overweight and Obese Adults

    PubMed Central

    Patel, Mahesh J.; Batch, Bryan C.; Svetkey, Laura P.; Bain, James R.; Turer, Christy Boling; Haynes, Carol; Muehlbauer, Michael J.; Stevens, Robert D.; Newgard, Christopher B.

    2013-01-01

    Abstract In overweight/obese individuals, cardiometabolic risk factors differ by race and sex categories. Small-molecule metabolites and metabolic hormone levels might also differ across these categories and contribute to risk factor heterogeneity. To explore this possibility, we performed a cross-sectional analysis of fasting plasma levels of 69 small-molecule metabolites and 13 metabolic hormones in 500 overweight/obese adults who participated in the Weight Loss Maintenance trial. Principal-components analysis (PCA) was used for reduction of metabolite data. Race and sex-stratified comparisons of metabolite factors and metabolic hormones were performed. African Americans represented 37.4% of the study participants, and females 63.0%. Of thirteen metabolite factors identified, three differed by race and sex: levels of factor 3 (branched-chain amino acids and related metabolites, p<0.0001), factor 6 (long-chain acylcarnitines, p<0.01), and factor 2 (medium-chain dicarboxylated acylcarnitines, p<0.0001) were higher in males vs. females; factor 6 levels were higher in Caucasians vs. African Americans (p<0.0001). Significant differences were also observed in hormones regulating body weight homeostasis. Among overweight/obese adults, there are significant race and sex differences in small-molecule metabolites and metabolic hormones; these differences may contribute to risk factor heterogeneity across race and sex subgroups and should be considered in future investigations with circulating metabolites and metabolic hormones. PMID:24117402

  7. Sex difference and postnatal change of maternal behavioral patterns in juvenile male and female rats.

    PubMed

    Shima, Satoshi; Urano, Aya; Korányi, Lajos; Yamanouchi, Korehito

    2005-06-01

    Juvenile rats are known to show certain elements of maternal behavior. In this experiment, to investigate sex difference and postnatal change of retrieving and pup-cleaning (licking) behaviors in juvenile rats, these behaviors were recorded using new observation method at 20, 30 and 45 days of age in female and male Wistar rats. At 20 days of age, maternal behavior was observed in a common plastic observation cage (test A) and then test B was performed. In the test B, observation was carried out using a cage with a wooden box that was open on one side, helping the juveniles to establish a nest. As the results of day 20, most rats in all groups showed licking behavior in both the test A and B. The incidence of retrieving behavior increased from the test A to the test B with the box in both sexes, especially in males (p<0.01). The box is thought to play a facilitative role in induction of retrieving. Moreover, the incidence in males was higher than that in females in the test B (p<0.001). At 30 and 45 days of age, only a test B with box was performed. The incidences of licking and retrieving behaviors at 30 days of age were decreased significantly compared to those at 20 days of age in both sexes(p<0.001). Further decrease from 30 days to 45 days was observed. These results suggest that in juvenile rat, incidence of retrieving behavior in males is higher than that in females but there is no sex difference in incidence of licking behavior. Potency to show these behaviors decreases acutely before puberty in rats. PMID:15988166

  8. 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

  9. Relationship dynamics and sexual risk behaviour of male partners of female sex workers in Kampala, Uganda.

    PubMed

    Mbonye, Martin; Siu, Godfrey E; Kiwanuka, Thadeus; Seeley, Janet

    2016-07-01

    Regular male partners of female sex workers (FSWs) represent an important population to reach with HIV-prevention interventions. This paper discusses the relationship dynamics and HIV/sexually transmitted infection risk behaviour of men involved with self-identified FSWs in Kampala. Between 2011 and 2014 we conducted repeat in-depth interviews with 42 male partners of FSWs attending a clinic for women at high risk of HIV-infection in Kampala. Men publicly struggled with the stigma of dating women who are considered to be engaged in a shamed profession, but privately saw meaning in these relationships. In coping with the stigma, some described the work of their partners in terms that distanced them from sex work, while others struggled to have the control that "being a man" demanded since they could not monitor all movements of their partners. Dealing with HIV disclosure was hard and seeking support was difficult for some of the men, leading to missed opportunities and guilt. Despite challenges, relationships with sex workers offered men some benefits such as access to much needed care and treatment. A few men also admitted to being motivated by material and financial benefits from sex workers who they perceived as being rich and this was one factor that helped them sustain the relationships. These findings offer insights into the complex relationship dynamics within high risk sexual partnerships. However, the findings suggest that effective interventions that are couple centred can be established to promote better health. PMID:27399044

  10. A method for estimating fall adult sex ratios from production and survival data

    USGS Publications Warehouse

    Wight, H.M.; Heath, R.G.; Geis, A.D.

    1965-01-01

    This paper presents a method of utilizing data relating to the production and survival of a bird population to estimate a basic fall adult sex ratio. This basic adult sex ratio is an average value derived from average production and survival rates. It is an estimate of the average sex ratio about which the fall adult ratios will fluctuate according to annual variations in production and survival. The basic fall adult sex ratio has been calculated as an asymptotic value which is the limit of an infinite series wherein average population characteristics are used as constants. Graphs are provided that allow the determination of basic sex ratios from production and survival data of a population. Where the respective asymptote has been determined, it may be possible to estimate various production and survival rates by use of variations of the formula for estimating the asymptote.

  11. Sexual history disclosure polygraph outcomes: do juvenile and adult sex offenders differ?

    PubMed

    Jensen, Todd M; Shafer, Kevin; Roby, C Y; Roby, Jini L

    2015-03-01

    Despite the empirical and theoretical chasm between the opponents and proponents of polygraphy, its use is prominent among sex offender agencies in the United States. However, current research on polygraph examination outcomes among juvenile sex offenders, along with potential differences from their adult counterparts, is scarce and outdated. In the present study, we assess the difference between juvenile and adult sex offenders in terms of the propensity for passing a sexual history disclosure polygraph examination. A sample of 324 sex offenders (86 juveniles and 238 adults) who engaged in a sexual history disclosure polygraph examination as part of their treatment in an Intermountain West sex offender treatment agency was used for the analysis. Results from preliminary and logistic regression analyses indicate that juvenile and adult offenders do not significantly differ in the likelihood of passing a sexual history disclosure polygraph examination. Implications and limitations are discussed. PMID:25049032

  12. 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

  13. 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

  14. Resistance circuit training reduced inflammatory cytokines in a cohort of male adults with Down syndrome

    PubMed Central

    Rosety-Rodriguez, Manuel; Camacho, Alejandra; Rosety, Ignacio; Fornieles, Gabriel; Rosety, Miguel A.; Diaz, Antonio J.; Rosety, Manuel; Ordonez, Francisco J.

    2013-01-01

    Background It is widely accepted that muscle strength plays a key role on functional tasks of daily living and employability in individuals with Down syndrome (DS). Recent studies have also reported resistance training may improve chronic inflammation in other clinical situations. This is the first study conducted to determine the effect of resistance circuit training on low-grade systemic inflammation in adults with DS. Material/Methods A total of 40 young male adults with DS were recruited for the trial through different community support groups for people with intellectual disabilities and their families. They had medical approval for physical activity participation. Twenty-four were randomly assigned to perform resistance circuit training with 6 stations, 3 days per week for 12 weeks. Exercise intensity was based on function of the 8RM assessments. The control group included 16 age-, sex-, and BMI-matched adults with Down syndrome. Plasma levels of leptin, adiponectin, and TNF-α were assessed by commercial ELISA kits. C-reactive protein (CRP) was assessed by nephelometry. Body composition was also determined, measuring fat-free mass percentage and waist circumference (WC). This protocol was approved by our Institutional Ethics Committee. Results Plasma levels of leptin, TNF-α, and IL-6 were significantly decreased after the completion of the training program, as were fat-free mass and WC. No sports-related injuries or withdrawals from the program were reported during the entire study period. No changes were observed in the control group. Conclusions Resistance circuit training improved low-grade systemic inflammation in male sedentary adults with DS. PMID:24196521

  15. National and State-Specific Health Insurance Disparities for Adults in Same-Sex Relationships

    PubMed Central

    Blewett, Lynn A.

    2014-01-01

    Objectives. We examined national and state-specific disparities in health insurance coverage, specifically employer-sponsored insurance (ESI) coverage, for adults in same-sex relationships. Methods. We used data from the American Community Survey to identify adults (aged 25–64 years) in same-sex relationships (n = 31 947), married opposite-sex relationships (n = 3 060 711), and unmarried opposite-sex relationships (n = 259 147). We estimated multinomial logistic regression models and state-specific relative differences in ESI coverage with predictive margins. Results. Men and women in same-sex relationships were less likely to have ESI than were their married counterparts in opposite-sex relationships. We found ESI disparities among adults in same-sex relationships in every region, but we found the largest ESI gaps for men in the South and for women in the Midwest. ESI disparities were narrower in states that had extended legal same-sex marriage, civil unions, and broad domestic partnerships. Conclusions. Men and women in same-sex relationships experience disparities in health insurance coverage across the country, but residing in a state that recognizes legal same-sex marriage, civil unions, or broad domestic partnerships may improve access to ESI for same-sex spouses and domestic partners. PMID:24328616

  16. Male Prison Inmates With Gender Dysphoria: When Is Sex Reassignment Surgery Appropriate?

    PubMed

    Osborne, Cynthia S; Lawrence, Anne A

    2016-10-01

    Gender dysphoria (GD), a feeling of persistent discomfort with one's biologic sex or assigned gender, is estimated to be more prevalent in male prison inmates than in nonincarcerated males; there may be 3000-4000 male inmates with GD in prisons in the United States. An increasing number of U.S. prison systems now offer gender dysphoric inmates diagnostic evaluation, psychotherapy, cross-sex hormone therapy, and opportunities, albeit limited, to enact their preferred gender role. Sex reassignment surgery (SRS), however, has not been offered to inmates except in response to litigation. In the first case of its kind, the California Department of Corrections and Rehabilitation recently agreed to provide SRS to an inmate and developed policy guidelines for its future provision. In other recent cases, U.S. courts have ruled that male inmates with GD are entitled to SRS when it is medically necessary. Although these decisions may facilitate the provision of SRS to inmates in the future, many U.S. prison systems will probably remain reluctant to offer SRS unless legally compelled to do so. In this review, we address the medical necessity of SRS for male inmates with GD. We also discuss eligibility criteria and the practical considerations involved in providing SRS to inmates. We conclude by offering recommendations for physicians, mental health professionals, and prison administrators, designed to facilitate provision of SRS to inmates with GD in a manner that provides humane treatment, maximizes the likelihood of successful outcomes, minimizes risk of regret, and generates data that can help inform future decisions. PMID:26979819

  17. On the Borders of Sexuality Research: Young People Who Have Sex with Both Males and Females

    ERIC Educational Resources Information Center

    Pallotta-Chiarolli, Maria

    2006-01-01

    As D'Augelli and Grossman point out, there is an underrepresentation in LGB research of "youth who have had sexual experiences with both males and females." Most of the information on bisexuality has been obtained from studies with adult samples, and it is "unclear to what extent a separate bisexual cultural identity is consolidated during…

  18. The Satellite Cell in Male and Female, Developing and Adult Mouse Muscle: Distinct Stem Cells for Growth and Regeneration

    PubMed Central

    Neal, Alice; Boldrin, Luisa; Morgan, Jennifer Elizabeth

    2012-01-01

    Satellite cells are myogenic cells found between the basal lamina and the sarcolemma of the muscle fibre. Satellite cells are the source of new myofibres; as such, satellite cell transplantation holds promise as a treatment for muscular dystrophies. We have investigated age and sex differences between mouse satellite cells in vitro and assessed the importance of these factors as mediators of donor cell engraftment in an in vivo model of satellite cell transplantation. We found that satellite cell numbers are increased in growing compared to adult and in male compared to female adult mice. We saw no difference in the expression of the myogenic regulatory factors between male and female mice, but distinct profiles were observed according to developmental stage. We show that, in contrast to adult mice, the majority of satellite cells from two week old mice are proliferating to facilitate myofibre growth; however a small proportion of these cells are quiescent and not contributing to this growth programme. Despite observed changes in satellite cell populations, there is no difference in engraftment efficiency either between satellite cells derived from adult or pre-weaned donor mice, male or female donor cells, or between male and female host muscle environments. We suggest there exist two distinct satellite cell populations: one for muscle growth and maintenance and one for muscle regeneration. PMID:22662253

  19. Connectivity differences between adult male and female patients with attention deficit hyperactivity disorder according to resting-state functional MRI

    PubMed Central

    Park, Bo-yong; Park, Hyunjin

    2016-01-01

    Attention deficit hyperactivity disorder (ADHD) is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have explored the differences. The purpose of this study was to quantify differences between adult male and female patients with ADHD based on neuroimaging and connectivity analysis. Resting-state functional magnetic resonance imaging scans were obtained and preprocessed in 82 patients. Group-wise differences between male and female patients were quantified using degree centrality for different brain regions. The medial-, middle-, and inferior-frontal gyrus, superior parietal lobule, precuneus, supramarginal gyrus, superior- and middle-temporal gyrus, middle occipital gyrus, and cuneus were identified as regions with significant group-wise differences. The identified regions were correlated with clinical scores reflecting depression and anxiety and significant correlations were found. Adult ADHD patients exhibit different levels of depression and anxiety depending on sex, and our study provides insight into how changes in brain circuitry might differentially impact male and female ADHD patients. PMID:26981099

  20. Sex-specific differences in risk factors for sarcopenia amongst community-dwelling older adults.

    PubMed

    Tay, L; Ding, Y Y; Leung, B P; Ismail, N H; Yeo, A; Yew, S; Tay, K S; Tan, C H; Chong, M S

    2015-12-01

    With considerable variation including potential sex-specific differential rate of skeletal muscle loss, identifying modifiable factors for sarcopenia will be pivotal to guide targeted interventions. This study seeks to identify clinical and biological correlates of sarcopenia in community-dwelling older adults, with emphasis on the role of anabolic and catabolic stimuli, and special reference to gender specificity. In this cross-sectional study involving 200 community-dwelling and functionally independent older adults aged ≥50 years, sarcopenia was defined using the Asian Working Group for Sarcopenia criteria. Comorbidities, cognitive and functional performance, physical activity and nutritional status were routinely assessed. Biochemical parameters included haematological indices, lipid panel, vitamin D level, anabolic hormones [insulin-like growth factor-1 (IGF-1), free testosterone (males only)] and catabolic markers [inflammatory markers (interleukin-6, C-reactive protein) and myostatin]. Multiple logistic regression was performed to identify independent predictors for sarcopenia. Age was associated with sarcopenia in both genders. Malnutrition conferred significantly higher odds for sarcopenia in women (OR = 5.71, 95% CI 1.13-28.84.44, p = 0.035) while higher but acceptable range serum triglyceride was protective in men (OR = 0.05, 95% CI 0.00-0.52, p = 0.012). Higher serum myostatin independently associated with higher odds for sarcopenia in men (OR = 1.11, 95% CI 1.00-1.24, p = 0.041). Serum IGF-1 was significantly lower amongst female sarcopenic subjects, with demonstrable trend for protective effect against sarcopenia in multiple regression models, such that each 1 ng/ml increase in IGF-1 was associated with 1% decline in odds of sarcopenia in women (p = 0.095). Our findings support differential pathophysiological mechanisms for sarcopenia that, if corroborated, may have clinical utility in guiding sex-specific targeted

  1. Sox9 and Sox8 protect the adult testis from male-to-female genetic reprogramming and complete degeneration

    PubMed Central

    Barrionuevo, Francisco J; Hurtado, Alicia; Kim, Gwang-Jin; Real, Francisca M; Bakkali, Mohammed; Kopp, Janel L; Sander, Maike; Scherer, Gerd; Burgos, Miguel; Jiménez, Rafael

    2016-01-01

    The new concept of mammalian sex maintenance establishes that particular key genes must remain active in the differentiated gonads to avoid genetic sex reprogramming, as described in adult ovaries after Foxl2 ablation. Dmrt1 plays a similar role in postnatal testes, but the mechanism of adult testis maintenance remains mostly unknown. Sox9 and Sox8 are required for postnatal male fertility, but their role in the adult testis has not been investigated. Here we show that after ablation of Sox9 in Sertoli cells of adult, fertile Sox8-/- mice, testis-to-ovary genetic reprogramming occurs and Sertoli cells transdifferentiate into granulosa-like cells. The process of testis regression culminates in complete degeneration of the seminiferous tubules, which become acellular, empty spaces among the extant Leydig cells. DMRT1 protein only remains in non-mutant cells, showing that SOX9/8 maintain Dmrt1 expression in the adult testis. Also, Sox9/8 warrant testis integrity by controlling the expression of structural proteins and protecting Sertoli cells from early apoptosis. Concluding, this study shows that, in addition to its crucial role in testis development, Sox9, together with Sox8 and coordinately with Dmrt1, also controls adult testis maintenance. DOI: http://dx.doi.org/10.7554/eLife.15635.001 PMID:27328324

  2. Sox9 and Sox8 protect the adult testis from male-to-female genetic reprogramming and complete degeneration.

    PubMed

    Barrionuevo, Francisco J; Hurtado, Alicia; Kim, Gwang-Jin; Real, Francisca M; Bakkali, Mohammed; Kopp, Janel L; Sander, Maike; Scherer, Gerd; Burgos, Miguel; Jiménez, Rafael

    2016-01-01

    The new concept of mammalian sex maintenance establishes that particular key genes must remain active in the differentiated gonads to avoid genetic sex reprogramming, as described in adult ovaries after Foxl2 ablation. Dmrt1 plays a similar role in postnatal testes, but the mechanism of adult testis maintenance remains mostly unknown. Sox9 and Sox8 are required for postnatal male fertility, but their role in the adult testis has not been investigated. Here we show that after ablation of Sox9 in Sertoli cells of adult, fertile Sox8(-/-) mice, testis-to-ovary genetic reprogramming occurs and Sertoli cells transdifferentiate into granulosa-like cells. The process of testis regression culminates in complete degeneration of the seminiferous tubules, which become acellular, empty spaces among the extant Leydig cells. DMRT1 protein only remains in non-mutant cells, showing that SOX9/8 maintain Dmrt1 expression in the adult testis. Also, Sox9/8 warrant testis integrity by controlling the expression of structural proteins and protecting Sertoli cells from early apoptosis. Concluding, this study shows that, in addition to its crucial role in testis development, Sox9, together with Sox8 and coordinately with Dmrt1, also controls adult testis maintenance. PMID:27328324

  3. Learning About Sex: The Contemporary Guide for Young Adults.

    ERIC Educational Resources Information Center

    Kelly, Gary F.

    This book provides information about sex to help readers, particularly teenagers, clarify their needs and values relating to sex--to understand sex, to deal with their own sexuality constructively and responsibly, and to deal with the sexuality of others in ways that are considerate and helpful. It is designed for either classroom or individual…

  4. Resting-State Brain Activity in Adult Males Who Stutter

    PubMed Central

    Zhu, Chaozhe; Wang, Liang; Yan, Qian; Lin, Chunlan; Yu, Chunshui

    2012-01-01

    Although developmental stuttering has been extensively studied with structural and task-based functional magnetic resonance imaging (fMRI), few studies have focused on resting-state brain activity in this disorder. We investigated resting-state brain activity of stuttering subjects by analyzing the amplitude of low-frequency fluctuation (ALFF), region of interest (ROI)-based functional connectivity (FC) and independent component analysis (ICA)-based FC. Forty-four adult males with developmental stuttering and 46 age-matched fluent male controls were scanned using resting-state fMRI. ALFF, ROI-based FCs and ICA-based FCs were compared between male stuttering subjects and fluent controls in a voxel-wise manner. Compared with fluent controls, stuttering subjects showed increased ALFF in left brain areas related to speech motor and auditory functions and bilateral prefrontal cortices related to cognitive control. However, stuttering subjects showed decreased ALFF in the left posterior language reception area and bilateral non-speech motor areas. ROI-based FC analysis revealed decreased FC between the posterior language area involved in the perception and decoding of sensory information and anterior brain area involved in the initiation of speech motor function, as well as increased FC within anterior or posterior speech- and language-associated areas and between the prefrontal areas and default-mode network (DMN) in stuttering subjects. ICA showed that stuttering subjects had decreased FC in the DMN and increased FC in the sensorimotor network. Our findings support the concept that stuttering subjects have deficits in multiple functional systems (motor, language, auditory and DMN) and in the connections between them. PMID:22276215

  5. Mating-induced differential coding of plant odour and sex pheromone in a male moth.

    PubMed

    Barrozo, Romina B; Jarriault, David; Deisig, Nina; Gemeno, Cesar; Monsempes, Christelle; Lucas, Philippe; Gadenne, Christophe; Anton, Sylvia

    2011-05-01

    Innate behaviours in animals can be influenced by several factors, such as the environment, experience, or physiological status. This behavioural plasticity originates from changes in the underlying neuronal substrate. A well-described form of plasticity is induced by mating. In both vertebrates and invertebrates, males experience a post-ejaculatory refractory period, during which they avoid new females. In the male moth Agrotis ipsilon, mating induces a transient inhibition of responses to the female-produced sex pheromone. To understand the neural bases of this inhibition and its possible odour specificity, we carried out a detailed analysis of the response characteristics of the different neuron types from the periphery to the central level. We examined the response patterns of pheromone-sensitive and plant volatile-sensitive neurons in virgin and mated male moths. By using intracellular recordings, we showed that mating changes the response characteristics of pheromone-sensitive antennal lobe (AL) neurons, and thus decreases their sensitivity to sex pheromone. Individual olfactory receptor neuron (ORN) recordings and calcium imaging experiments indicated that pheromone sensory input remains constant. On the other hand, calcium responses to non-pheromonal odours (plant volatiles) increased after mating, as reflected by increased firing frequencies of plant-sensitive AL neurons, although ORN responses to heptanal remained unchanged. We suggest that differential processing of pheromone and plant odours allows mated males to transiently block their central pheromone detection system, and increase non-pheromonal odour detection in order to efficiently locate food sources. PMID:21488987

  6. Genetic manipulation of sex ratio for the large-scale breeding of YY super-male and XY all-male yellow catfish (Pelteobagrus fulvidraco (Richardson)).

    PubMed

    Liu, Hanqin; Guan, Bo; Xu, Jiang; Hou, Changchun; Tian, Hua; Chen, Hongxi

    2013-06-01

    Yellow catfish has become one of the most important freshwater aquaculture species in China. The mono-sex male yellow catfish has important application value in aquaculture because the male grows generally faster than the sibling females under the same conditions. This study has screened YY super-male and YY physiological female yellow catfish by sex reversal, gynogenesis, and progeny testing, which can help to achieve the large-scale production of YY super-male and XY all-male. From 2008 to 2010, about 123,000 YY super-male were produced, and about 81 million XY all-male fry were produced with 100% male rate by random sampling. Therefore, these results indicate that YY super-male and YY physiological female yellow catfish can be viable and fertile. We conclude that the mono-sex breeding technique by YY super-male yellow catfish is stable and reliable, which has great potential for application in yellow catfish aquaculture. PMID:23053056

  7. 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

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

    PubMed Central

    Larsson, D G Joakim; Förlin, 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

  9. Early Life Manipulations of the Nonapeptide System Alter Pair Maintenance Behaviors and Neural Activity in Adult Male Zebra Finches

    PubMed Central

    Baran, Nicole M.; Tomaszycki, Michelle L.; Adkins-Regan, Elizabeth

    2016-01-01

    Adult zebra finches (T. guttata) form socially monogamous pair bonds characterized by proximity, vocal communication, and contact behaviors. In this experiment, we tested whether manipulations of the nonapeptide hormone arginine vasotocin (AVT, avian homolog of vasopressin) and the V1a receptor (V1aR) early in life altered species-typical pairing behavior in adult zebra finches of both sexes. Although there was no effect of treatment on the tendency to pair in either sex, males in different treatments exhibited profoundly different profiles of pair maintenance behavior. Following a brief separation, AVT-treated males were highly affiliative with their female partner but sang very little compared to Controls. In contrast, males treated with a V1aR antagonist sang significantly less than Controls, but did not differ in affiliation. These effects on behavior in males were also reflected in changes in the expression of V1aR and immediate early gene activity in three brain regions known to be involved in pairing behavior in birds: the medial amygdala, medial bed nucleus of the stria terminalis, and the lateral septum. AVT males had higher V1aR expression in the medial amygdala than both Control and antagonist-treated males and immediate early gene activity of V1aR neurons in the medial amygdala was positively correlated with affiliation. Antagonist treated males showed decreased activity in the medial amygdala. In addition, there was a negative correlation between the activity of V1aR cells in the medial bed nucleus of the stria terminalis and singing. Treatment also affected the expression of V1aR and activity in the lateral septum, but this was not correlated with any behaviors measured. These results provide evidence that AVT and V1aR play developmental roles in specific pair maintenance behaviors and the neural substrate underlying these behaviors in a bird. PMID:27065824

  10. Early Life Manipulations of the Nonapeptide System Alter Pair Maintenance Behaviors and Neural Activity in Adult Male Zebra Finches.

    PubMed

    Baran, Nicole M; Tomaszycki, Michelle L; Adkins-Regan, Elizabeth

    2016-01-01

    Adult zebra finches (T. guttata) form socially monogamous pair bonds characterized by proximity, vocal communication, and contact behaviors. In this experiment, we tested whether manipulations of the nonapeptide hormone arginine vasotocin (AVT, avian homolog of vasopressin) and the V1a receptor (V1aR) early in life altered species-typical pairing behavior in adult zebra finches of both sexes. Although there was no effect of treatment on the tendency to pair in either sex, males in different treatments exhibited profoundly different profiles of pair maintenance behavior. Following a brief separation, AVT-treated males were highly affiliative with their female partner but sang very little compared to Controls. In contrast, males treated with a V1aR antagonist sang significantly less than Controls, but did not differ in affiliation. These effects on behavior in males were also reflected in changes in the expression of V1aR and immediate early gene activity in three brain regions known to be involved in pairing behavior in birds: the medial amygdala, medial bed nucleus of the stria terminalis, and the lateral septum. AVT males had higher V1aR expression in the medial amygdala than both Control and antagonist-treated males and immediate early gene activity of V1aR neurons in the medial amygdala was positively correlated with affiliation. Antagonist treated males showed decreased activity in the medial amygdala. In addition, there was a negative correlation between the activity of V1aR cells in the medial bed nucleus of the stria terminalis and singing. Treatment also affected the expression of V1aR and activity in the lateral septum, but this was not correlated with any behaviors measured. These results provide evidence that AVT and V1aR play developmental roles in specific pair maintenance behaviors and the neural substrate underlying these behaviors in a bird. PMID:27065824

  11. Differences in Relationship Characteristics Between HIV-Negative Male Couples Who Used and Did Not Use Substances with Sex.

    PubMed

    Mitchell, Jason W

    2016-03-01

    Although substance use is linked to HIV seroconversion, little is known about male couples substance use with sex. The present study sought to: describe whether neither, one, or both partners in the couple used a particular substance with sex within or outside their relationship; assess, by substance type used with sex, whether relationship factors differed between these groups of couples. Dyadic data from 83 behaviorally non-monogamous HIV-negative male couples were used with multinomial regression models. Those who used with sex within the relationship varied by substance type; outside the relationship, most only had one partner who used with sex. Couples with one or both partners who used substances with sex within or outside the relationship were more likely to have higher commitment to their relationship yet less likely to trust their main partner; mixed results were found regarding communication. Further research is warranted toward the need for preventive intervention development. PMID:26223222

  12. Sexually explicit media on the internet: a content analysis of sexual behaviors, risk, and media characteristics in gay male adult videos.

    PubMed

    Downing, Martin J; Schrimshaw, Eric W; Antebi, Nadav; Siegel, Karolynn

    2014-05-01

    Recent research suggests that viewing sexually explicit media (SEM), i.e., adult videos, may influence sexual risk taking among men who have sex with men. Despite this evidence, very little is known about the content of gay male SEM on the Internet, including the prevalence of sexual risk behaviors and their relation to video- and performer-characteristics, viewing frequency, and favorability. The current study content analyzed 302 sexually explicit videos featuring male same-sex performers that were posted to five highly trafficked adult-oriented websites. Findings revealed that gay male SEM on the Internet features a variety of conventional and nonconventional sexual behaviors. There was a substantial prevalence of unprotected anal intercourse (UAI) (34 %) and was virtually the same as the prevalence of anal sex with a condom (36 %). The presence of UAI was not associated with video length, amateur production, number of video views, favorability, or website source. However, the presence of other potentially high-risk behaviors (e.g., ejaculation in the mouth, and ejaculation on/in/rubbed into the anus) was associated with longer videos, more views, and group sex videos (three or more performers). The findings of high levels of sexual risk behavior and the fact that there was virtually no difference in the prevalence of anal sex with and without a condom in gay male SEM have important implications for HIV prevention efforts, future research on the role of SEM on sexual risk taking, and public health policy. PMID:23733156

  13. Sexually Explicit Media on the Internet: A Content Analysis of Sexual Behaviors, Risk, and Media Characteristics in Gay Male Adult Videos

    PubMed Central

    Downing, Martin J.; Schrimshaw, Eric W.; Antebi, Nadav; Siegel, Karolynn

    2013-01-01

    Recent research suggests that viewing sexually explicit media (SEM), i.e., adult videos, may influence sexual risk taking among men who have sex with men (MSM). Despite this evidence, very little is known about the content of gay male SEM on the Internet, including the prevalence of sexual risk behaviors and their relation to video- and performer-characteristics, viewing frequency, and favorability. The current study content analyzed 302 sexually explicit videos featuring male same-sex performers that were posted to five highly trafficked adult-oriented websites. Findings revealed that gay male SEM on the Internet features a variety of conventional and nonconventional sexual behaviors. There was a substantial prevalence of unprotected anal intercourse (UAI) (34%) and was virtually the same as the prevalence of anal sex with a condom (36%). The presence of UAI was not associated with video length, amateur production, number of video views, favorability, or website source. However, the presence of other potentially high-risk behaviors (e.g., ejaculation in the mouth, and ejaculation on/in/rubbed into the anus) was associated with longer videos, more views, and group sex videos (three or more performers). The findings of high levels of sexual risk behavior and the fact that there was virtually no difference in the prevalence of anal sex with and without a condom in gay male SEM have important implications for HIV prevention efforts, future research on the role of SEM on sexual risk taking, and public health policy. PMID:23733156

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

    PubMed Central

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

    2013-01-01

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

  15. Fine structure and meiotic behaviour of the male multiple sex chromosomes in the genus Alouatta.

    PubMed

    Solari, A J; Rahn, M I

    2005-01-01

    The meiotic cytology and fine structure of the sex multiples in males from two species of the genus Alouatta are presented and compared with descriptions from other species of this genus. As shown in pachytene by synaptonemal complex analysis and in metaphase I by spreading, there is a quadrivalent in male meiosis in A. caraya, which is formed by an X(1)X(2)Y(1)Y(2) complex, while in A. palliata there is a trivalent formed by an X(1)X(2)Y(1) complex. Chromosome painting with human probes shows that A. caraya sex multiples share the same components as those of A. seniculus sara and A. seniculus arctoidea. However, as shown here for A. palliata and by others in A. fusca, there are differences among the multiples of some species. It is shown that in this genus there are several varieties of sex multiples that share some features, and that the origin of these multiples is most probably a primitive development in the genus Alouatta. PMID:15545739

  16. Occupational HIV Transmission Among Male Adult Film Performers - Multiple States, 2014.

    PubMed

    Wilken, Jason A; Ried, Christopher; Rickett, Pristeen; Arno, Janet N; Mendez, Yesenia; Harrison, Robert J; Wohlfeiler, Dan; Bauer, Heidi M; Joyce, M Patricia; Switzer, William M; Heneine, Walid; Shankar, Anupama; Mark, Karen E

    2016-02-12

    In 2014, the California Department of Public Health was notified by a local health department of a diagnosis of acute human immunodeficiency virus (HIV) infection* and rectal gonorrhea in a male adult film industry performer, aged 25 years (patient A). Patient A had a 6-day history of rash, fever, and sore throat suggestive of acute retroviral syndrome at the time of examination. He was informed of his positive HIV and gonorrhea test results 6 days after his examination. Patient A had a negative HIV-1 RNA qualitative nucleic acid amplification test (NAAT)(†) 10 days before symptom onset. This investigation found that during the 22 days between the negative NAAT and being informed of his positive HIV test results, two different production companies directed patient A to have condomless sex with a total of 12 male performers. Patient A also provided contact information for five male non-work-related sexual partners during the month before and after his symptom onset. Patient A had additional partners during this time period for which no locating information was provided. Neither patient A nor any of his interviewed sexual partners reported taking HIV preexposure prophylaxis (PrEP). Contact tracing and phylogenetic analysis of HIV sequences amplified from pretreatment plasma revealed that a non-work-related partner likely infected patient A, and that patient A likely subsequently infected both a coworker during the second film production and a non-work-related partner during the interval between his negative test and receipt of his positive HIV results. Adult film performers and production companies, medical providers, and all persons at risk for HIV should be aware that testing alone is not sufficient to prevent HIV transmission. Condom use provides additional protection from HIV and sexually transmitted infections (STIs). Performers and all persons at risk for HIV infection in their professional and personal lives should discuss the use of PrEP with their medical

  17. 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

  18. 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

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

    PubMed Central

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

    2015-01-01

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

  20. 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

  1. The bed nucleus of the stria terminalis has developmental and adult forms in mice, with the male bias in the developmental form being dependent on testicular AMH.

    PubMed

    Wittmann, Walter; McLennan, Ian S

    2013-09-01

    Canonically, the sexual dimorphism in the brain develops perinatally, with adult sexuality emerging due to the activating effects of pubescent sexual hormones. This concept does not readily explain why children have a gender identity and exhibit sex-stereotypic behaviours. These phenomena could be explained if some aspects of the sexual brain networks have childhood forms, which are transformed at puberty to generate adult sexuality. The bed nucleus of stria terminalis (BNST) is a dimorphic nucleus that is sex-reversed in transsexuals but not homosexuals. We report here that the principal nucleus of the BNST (BNSTp) of mice has developmental and adult forms that are differentially regulated. In 20-day-old prepubescent mice, the male bias in the principal nucleus of the BNST (BNSTp) was moderate (360 ± 6 vs 288 ± 12 calbindin(+ve) neurons, p < 0.0001), and absent in mice that lacked a gonadal hormone, AMH. After 20 days, the number of BNSTp neurons increased in the male mice by 25% (p < 0.0001) and decreased in female mice by 15% (p = 0.0012), independent of AMH. Adult male AMH-deficient mice had a normal preference for sniffing female pheromones (soiled bedding), but exhibited a relative disinterest in both male and female pheromones. This suggests that male mice require AMH to undergo normal social development. The reported observations provide a rationale for examining AMH levels in children with gender identity disorders and disorders of socialization that involve a male bias. PMID:24012942

  2. 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

  3. Effects of sex role attitudes and similarity on men's rejection of male homosexuals.

    PubMed

    Krulewitz, J E; Nash, J E

    1980-01-01

    The present study investigated reactions to homosexuals as a function of perceived attitude similarity and subjects' sex role attitudes. Male subjects, preselected on the basis of their profeminist, moderate, or antifeminist scores on the Attitude Toward Feminism Scale were assigned at random to one of the four experimental conditions. Using a standard attraction paradigm design, subjects rated a bogus "partner," who was represented as either homosexual or heterosexual and as having attitudes either similar or dissimilar to theirs. Consistent with predictions, similar partners were liked more than dissimilar partners, and heterosexual partners were liked more than homosexuals. Homosexuals were seen as more dissimilar to the subjects in all conditions. Further, liberals were more accepting of homosexuals and dissimilar partners than were traditionals. The results are discussed in terms of the relationship between sex role attitudes and tolerance of dissimilarity. PMID:7373510

  4. 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.

  5. 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

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

    PubMed

    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

  7. 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

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

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2012-01-01

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

  10. GENERAL STRAIN THEORY, PERSISTENCE, AND DESISTANCE AMONG YOUNG ADULT MALES

    PubMed Central

    Eitle, David

    2010-01-01

    Purpose Despite the surge in scholarly activity investigating the criminal career, relatively less attention has been devoted to the issue of criminal desistance versus persistence (until recently). The present study contributed to our understanding of this process by exploring the suitability of General Strain Theory (GST) for predicting changes in criminal activity across time. Methods Data from a longitudinal study of males in South Florida are examined using robust regression analyses. Results The core GST relationship, that changes in strain should predict changes in criminal activity, was supported, even after controlling for important adult social roles such as marriage, labor force participation, and education. While no support for the proposition that changes in self-esteem and social support moderate the strain-criminal desistance association was evinced, evidence was found that angry disposition, a measure of negative emotionality, moderated the association between change in chronic stressors and change in criminal activity. Conclusions While exploratory in nature, these findings demonstrate the utility of employing GST principles in studies of criminal desistance. PMID:21499526

  11. Position of the mandibular foramen in adult male Tanzania mandibles.

    PubMed

    Russa, Afadhali D; Fabian, Flora M

    2014-01-01

    Failure of the inferior alveolar nerve block anesthesia is common in various dental operations. Anatomical variations of the location of the inferior alveolar nerve as it enters the mandibular foramen have been implicated as a main cause of these anesthesia failures. The aim of this work was to determine the location of the mandibular foramen in relation to the occlusal plane at the level of mandibular first molar and second premolar--often used as landmarks during the blocking procedure--and to different landmarks on the ramus of the mandible. The study was performed using mandibles from adult black male Tanzanians aged 30-45 years. Measurements were accomplished using two-digit electronic Vernier calipers. The distances were determined from the center of the mandibular foramen to the different reference points. The mandibular foramen was above the occlusal plane at the M1 and PM2 reference points in all the mandibles studied. It was also located about 20 mm and 12 mm from the anterior and posterior borders of the ramus respectively. There was no significant difference between the left and right side in any of the measurements. These results indicate that during anesthetic or other clinical procedures, the clinician can precisely determine the position of neurovascular bundle of the inferior alveolar nerve above the occlusal plane. PMID:26749676

  12. Loud calls of adult male red howling monkeys (Alouatta seniculus).

    PubMed

    Schön Ybarra, M A

    1986-01-01

    Loud calls of adult male red howlers (Alouatta seniculus) inhabiting a deciduous and semideciduous open woodland site in Venezuela were recorded opportunistically and categorized by ear and sonographically as barks and roars. Five to six different bark syllables were identified as occurring singly or in sequences of doublets and triplets. In barks, spectral energy was concentrated in bands at 350-400 Hz, 900-1,100 Hz, 1,800-2,200 Hz and 3,000-3,500 Hz, but not all higher bands were present in each syllable. Roars appeared sonographically like prolonged barks composed of a pulsated preface, a long legato climax and a brief, fractionated and at times pulsated coda; each part varied internally to the ear and in acoustic structure. All loud calls were of the noisy type (nonharmonic energy over a broad frequency range). Acoustic characteristics of the calls are interpreted in terms of the subserving vocal tract anatomy. I compare loud calls of red howlers with those of mantled (A. palliata) and black (A. caraya) howlers. PMID:3609972

  13. Does sex (female versus male) influence the impact of class attendance on examination performance?

    PubMed

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

    2011-12-01

    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 examining the impact of attendance on course grades that challenge the conventional wisdom. To address these issues, we determined the effect of class attendance on examination scores for female and male students enrolled in our undergraduate exercise physiology class of 51 students (20 female students and 31 male students). The experiment was designed not to interfere with the normal conduct of the course. Attendance was recorded in each class, and, although regular attendance was encouraged, it was not required and did not factor into the final grades. The final grade reflected the average days of attendance for female students only. Specifically, female students earning a grade above the class average attended 89 ± 4% of the classes; however, female students earning a grade below the class average attended only 64 ± 6% of the classes. In sharp contrast, there was no difference in the number of classes attended for male students earning grades above or below the class average (84 ± 3% vs. 79 ± 5%). Accordingly, some male students were absent frequently but scored above the class average, whereas other male students attended many classes but scored below the class average. Thus, the influence of regular attendance on examination performance is more important for female students than male students. PMID:22139780

  14. Sex Role Orientation Across the Adult Life Span.

    ERIC Educational Resources Information Center

    Zaks, Peggy M.; And Others

    It was hypothesized that four different "life lines" would affect sex role orientations, specifically intimacy, parenting, grandparenting, and work. Subjects were 74 men and 43 women, white, upper middle class with a mean education level of 14 years. Each participant completed a demographic questionnaire, the Bem Sex Role Inventory, a Life Events…

  15. [Mutagenic effect of human adenovirus type I on the somatic and sex cells of male mice].

    PubMed

    Podol'skaia, S V

    1986-01-01

    Human adenovirus 1 was studied for its effect on the chromosomal apparatus both in bone marrow cells and male sex cells of mice. Chromosome aberrations were most early detected in spermatocytes of the 1st order mice infected with human adenovirus 1. In bone marrow cells of mice the highest level of chromosome aberrations was observed 30, 60, 90 days after the inoculation, which corresponds to a more frequent detection of the adenoviral antigen. The UV-irradiated-virus caused chromosome aberrations in the later periods after the inoculation which might be induced by the virus reactivation in a cell. PMID:3705168

  16. The Child's Expectations of Differences in Adult Male and Female Interactions.

    ERIC Educational Resources Information Center

    Fagot, Beverly I.

    1984-01-01

    Two-year-olds and four-year-olds were placed with male and female adults in a play situation where the children were forced to control the choice of toys and mode of interaction. The four-year-olds elicited different types of play behaviors from male and female adults; the younger children did not. (Author/KH)

  17. Personality Profiles of Adult Males Sexually Molested by Their Maternal Caregivers: Preliminary Findings.

    ERIC Educational Resources Information Center

    Roys, Deloris T.; Timms, Robert J.

    1995-01-01

    Examined two groups of adult males who had been sexually abused as children by female maternal caregivers: those in treatment at a clinic specializing in sexual abuse survivor work, and those in treatment at a clinic specializing in sexual offender work. These groups show greater psychological disruption than adult males who as children had not…

  18. Adult male mice conceived by in vitro fertilization exhibit increased glucocorticoid receptor expression in fat tissue.

    PubMed

    Simbulan, R K; Liu, X; Feuer, S K; Maltepe, E; Donjacour, A; Rinaudo, P

    2016-02-01

    Prenatal development is highly plastic and readily influenced by the environment. Adverse conditions have been shown to alter organ development and predispose offspring to chronic diseases, including diabetes and hypertension. Notably, it appears that the changes in glucocorticoid hormones or glucocorticoid receptor (GR) levels in peripheral tissues could play a role in the development of chronic diseases. We have previously demonstrated that in vitro fertilization (IVF) and preimplantation embryo culture is associated with growth alterations and glucose intolerance in mice. However, it is unknown if GR signaling is affected in adult IVF offspring. Here we show that GR expression is increased in inbred (C57Bl6/J) and outbred (CF-1× B6D2F1/J) blastocysts following in vitro culture and elevated levels are also present in the adipose tissue of adult male mice. Importantly, genes involved in lipolysis and triglyceride synthesis and responsive to GR were also increased in adipose tissue, indicating that increased GR activates downstream gene pathways. The promoter region of GR, previously reported to be epigenetically modified by perinatal manipulation, showed no changes in DNA methylation status. Our findings demonstrate that IVF results in a long-term change in GR gene expression in a sex- and tissue-specific manner. These changes in adipose tissues may well contribute to the metabolic phenotype in mice conceived by IVF. PMID:26511158

  19. Differential Interactions of Sex Pheromone and Plant Odour in the Olfactory Pathway of a Male Moth

    PubMed Central

    Deisig, Nina; Kropf, Jan; Vitecek, Simon; Pevergne, Delphine; Rouyar, Angela; Sandoz, Jean-Christophe; Lucas, Philippe; Gadenne, Christophe

    2012-01-01

    Most animals rely on olfaction to find sexual partners, food or a habitat. The olfactory system faces the challenge of extracting meaningful information from a noisy odorous environment. In most moth species, males respond to sex pheromone emitted by females in an environment with abundant plant volatiles. Plant odours could either facilitate the localization of females (females calling on host plants), mask the female pheromone or they could be neutral without any effect on the pheromone. Here we studied how mixtures of a behaviourally-attractive floral odour, heptanal, and the sex pheromone are encoded at different levels of the olfactory pathway in males of the noctuid moth Agrotis ipsilon. In addition, we asked how interactions between the two odorants change as a function of the males' mating status. We investigated mixture detection in both the pheromone-specific and in the general odorant pathway. We used a) recordings from individual sensilla to study responses of olfactory receptor neurons, b) in vivo calcium imaging with a bath-applied dye to characterize the global input response in the primary olfactory centre, the antennal lobe and c) intracellular recordings of antennal lobe output neurons, projection neurons, in virgin and newly-mated males. Our results show that heptanal reduces pheromone sensitivity at the peripheral and central olfactory level independently of the mating status. Contrarily, heptanal-responding olfactory receptor neurons are not influenced by pheromone in a mixture, although some post-mating modulation occurs at the input of the sexually isomorphic ordinary glomeruli, where general odours are processed within the antennal lobe. The results are discussed in the context of mate localization. PMID:22427979

  20. 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…

  1. 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

  2. Correlates of self-efficacy for condom use among male clients of female sex workers in Tijuana, Mexico.

    PubMed

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

    2014-05-01

    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 4 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

  3. 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

  4. 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

  5. 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

  6. Sex and condom use in a large jail unit for men who have sex with men (MSM) and male-to-female transgenders.

    PubMed

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

    2010-08-01

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

  7. Psychopathic traits are associated with reduced attention to the eyes of emotional faces among adult male non-offenders

    PubMed Central

    Gillespie, Steven M.; Rotshtein, Pia; Wells, Laura J.; Beech, Anthony R.; Mitchell, Ian J.

    2015-01-01

    Psychopathic traits are linked with impairments in emotional facial expression recognition. These impairments may, in part, reflect reduced attention to the eyes of emotional faces. Although reduced attention to the eyes has been noted among children with conduct problems and callous-unemotional traits, similar findings are yet to be found in relation to psychopathic traits among adult male participants. Here we investigated the relationship of primary (selfish, uncaring) and secondary (impulsive, antisocial) psychopathic traits with attention to the eyes among adult male non-offenders during an emotion recognition task. We measured the number of fixations, and overall dwell time, on the eyes, and the mouth of male and female faces showing the six basic emotions at varying levels of intensity. We found no relationship of primary or secondary psychopathic traits with recognition accuracy. However, primary psychopathic traits were associated with a reduced number of fixations, and lower overall dwell time, on the eyes relative to the mouth across expressions, intensity, and sex. Furthermore, the relationship of primary psychopathic traits with attention to the eyes of angry and fearful faces was influenced by the sex and intensity of the expression. We also showed that a greater number of fixations on the eyes, relative to the mouth, were associated with increased accuracy for angry and fearful expression recognition. These results are the first to show effects of psychopathic traits on attention to the eyes of emotional faces in an adult male sample, and may support amygdala based accounts of psychopathy. These findings may also have methodological implications for clinical studies of emotion recognition. PMID:26500524

  8. Psychopathic traits are associated with reduced attention to the eyes of emotional faces among adult male non-offenders.

    PubMed

    Gillespie, Steven M; Rotshtein, Pia; Wells, Laura J; Beech, Anthony R; Mitchell, Ian J

    2015-01-01

    Psychopathic traits are linked with impairments in emotional facial expression recognition. These impairments may, in part, reflect reduced attention to the eyes of emotional faces. Although reduced attention to the eyes has been noted among children with conduct problems and callous-unemotional traits, similar findings are yet to be found in relation to psychopathic traits among adult male participants. Here we investigated the relationship of primary (selfish, uncaring) and secondary (impulsive, antisocial) psychopathic traits with attention to the eyes among adult male non-offenders during an emotion recognition task. We measured the number of fixations, and overall dwell time, on the eyes, and the mouth of male and female faces showing the six basic emotions at varying levels of intensity. We found no relationship of primary or secondary psychopathic traits with recognition accuracy. However, primary psychopathic traits were associated with a reduced number of fixations, and lower overall dwell time, on the eyes relative to the mouth across expressions, intensity, and sex. Furthermore, the relationship of primary psychopathic traits with attention to the eyes of angry and fearful faces was influenced by the sex and intensity of the expression. We also showed that a greater number of fixations on the eyes, relative to the mouth, were associated with increased accuracy for angry and fearful expression recognition. These results are the first to show effects of psychopathic traits on attention to the eyes of emotional faces in an adult male sample, and may support amygdala based accounts of psychopathy. These findings may also have methodological implications for clinical studies of emotion recognition. PMID:26500524

  9. The Effect of Sex Labels on Adults' Knowledge of Infant Development.

    ERIC Educational Resources Information Center

    Paludi, Michele, A.; Gullo, Dominic F.

    1987-01-01

    Adults indicated on questionnaires the age at which they believed infants were first able to perform various developmental skills. Some questionnaires asked about "boys," some about "girls," and some about "babies." Contrary to previous findings, sex labels did not affect adults' rating of behaviors. (Author/LHW)

  10. Poverty, Rape, Adult/Teen Sex: Why "Pregnancy Prevention" Programs Don't Work.

    ERIC Educational Resources Information Center

    Males, Mike

    1994-01-01

    Stephen Caldas assumes that modern "teenage" sex and pregnancy are deviant, isolatable behaviors. However, teenage and adult sexual behaviors are so intertwined at the personal and societal levels that there is no distinct teenage phenomenon amenable to school intervention. Attempting to preach values contradicting the values adults practice is…

  11. Adults' Complicity in Limiting Students' Understanding of Sex, Gender and Sexuality at School

    ERIC Educational Resources Information Center

    Mayo, J. B., Jr.

    2016-01-01

    This article is a commentary on the seven papers in this special issue of "Sex Education." A compelling theme interwoven throughout all the articles in subtle and explicit ways is the role that adults play in the lives of students, particularly in the ways in which adults impact how students enact and respond to the multiple…

  12. Antiretroviral Therapy as a Factor Protective against Anal Dysplasia in HIV-Infected Males Who Have Sex with Males

    PubMed Central

    Hidalgo-Tenorio, Carmen; Rivero-Rodriguez, Mar; Gil-Anguita, Concepción; Lopez De Hierro, Mercedes; Palma, Pablo; Ramírez-Taboada, Jessica; Esquivias, Javier; López-Ruz, Miguel Angel; Javier-Martínez, Rosario; Pasquau-Liaño, Juan

    2014-01-01

    Objectives Chronic infection with oncogenic HPV genotype is associated with the development of anal dysplasia. Antiretroviral therapy (ART) has been shown to decrease the incidence of cervical carcinoma in women with HIV. We sought to: 1) describe the prevalence and grade of anal dysplasia and HPV infection in our study subjects; 2) analyze the grade of correlation between anal cytology, PCR of high-risk HPV, and histology; 3) identify the factors associated with the appearance of ≥AIN2 lesions. Design Cross-sectional, prospective study. Methods A cohort of HIV-positive males (n = 140, mean age  = 37 years) who have sex with males (MSM) had epidemiological, clinical and analytical data collected. Anal mucosa samples were taken for cytology, HPV PCR genotyping, and anoscopy for histological analysis. Results Within the cohort, 77.1% were being treated with ART, 8.5% anoscopy findings were AIN2, and 11.4% carcinoma in situ; 74.2% had high-risk (HR), 59.7% low-risk (LR) HPV genotypes and 46.8% had both. The combination of cytology with PCR identifying HR-HPV better predicts the histology findings than either of these factors alone. Logistic regression highlighted ART as a protective factor against ≥AIN2 lesions (OR: 0.214; 95%CI: 0.054–0.84). Anal/genital condylomas (OR: 4.26; 95%CI: 1.27–14.3), and HPV68 genotype (OR: 10.6; 95%CI: 1.23–91.47) were identified as risk factors. Conclusions In our cohort, ART has a protective effect against dysplastic anal lesions. Anal/genital warts and HPV68 genotype are predictors of ≥AIN2 lesions. Introducing PCR HPV genotype evaluation improves screening success over that of cytology alone. PMID:24676139

  13. X-ray sterilization of the An. arabiensis genetic sexing strain 'ANO IPCL1' at pupal and adult stages.

    PubMed

    Ndo, C; Yamada, H; Damiens, D D; N'do, S; Seballos, G; Gilles, J R L

    2014-03-01

    With a view to area wide integrated pest management programs with a sterile insect technique (SIT) component against the malaria vector Anopheles arabiensis, the effects of X-ray exposure of males of the genetic sexing strain (GSS) of An. arabiensis, "ANO IPCL1" have been tested. The suitability of X-ray was assessed in comparison to gamma-ray for mosquito sterilization in operational settings where the acquisition of gamma ray irradiators may be problematic. Pupae and adult males were sterilized using X-ray irradiation at 5 increasing doses and effects were observed in terms of fecundity and fertility. Irradiated pupae and adults were further observed for effects on longevity. The adult stage appeared to be more sensitive to radiation exposure than the pupal stage, with a residual fertility of 1% in adults irradiated at 75Gy and 0% at 105Gy, compared to 8%at 75Gy and 4% at 105Gy in adults irradiated at the pupal stage. All treatment groups except those irradiated at 60Gy were statistically different from the control groups in terms of adult longevity post treatment, however overall survival was not highly compromised in the 75Gy treatment group which showed 96% of induced sterility. To ensure the fine balance between the induced sterility and the fitness of the insect produced is achieved, irradiation of adults at this dose may be a good compromise for the SIT as applied for this species, especially in specific cases such as sterilization after female elimination by spiking blood meals. Investigation into the combined effects of blood spiking and irradiation at the adult stage and additional competitiveness studies both in laboratory and field cages will provide more insight into the radiation dose and mosquito stage to be used in the frame of future SIT programs targeting this important malaria vector. PMID:24361725

  14. Beyond Sex Education: How Adults Relate to Children's Sensuality.

    ERIC Educational Resources Information Center

    Fogel, Alan

    Current cultural attitudes toward children's sexuality resemble attitudes toward adults' sexuality; there is an emphasis on purely genital and orgasmic pleasure. Adults and children need warmth, physical contact, and a sense of belonging for which genital stimulation may be unnecessary or inappropriate. Children's sexual advances to adults, as…

  15. The Role of Clitoral Anatomy in Female to Male Sex Reassignment Surgery

    PubMed Central

    2014-01-01

    Introduction. Controversies on clitoral anatomy and its role in female sexual function still make clitoral reconstructive surgery very challenging. We evaluated the role of clitoral anatomic features in female to male sex reassignment surgery. Material and Methods. The study included 97 female transsexuals, aged from 18 to 41 years, who underwent single stage metoidioplasty between March 2008 and January 2013. The operative technique involved vaginectomy, the release of clitoral ligaments and urethral plate, urethroplasty by combining buccal mucosa graft and genital flaps, and scrotoplasty with insertion of testicle prostheses. Postoperative questionnaire was used to evaluate aesthetic, functional, and sexual outcome. Results. The mean followup was 30 months. The mean length of the neophallus was 7 cm, compared to mean preoperative length of the hypertrophied clitoris of 3.3 cm. Complications occurred in 27.84% of all patients, related mostly to urethroplasty. Voiding while standing was achieved in all cases. None of the patients had problems in sexual arousal, masturbation, or orgasms. Conclusion. Accurate knowledge of the clitoral anatomy, physiology, and neurovascular supply is crucial for a successful outcome of female to male sex reassignment surgery. Our approach appears to ensure overall satisfaction and high quality of sexual life. PMID:24982953

  16. The epidemiology of HIV and syphilis among male commercial sex workers in northern Thailand.

    PubMed

    Kunawararak, P; Beyrer, C; Natpratan, C; Feng, W; Celentano, D D; de Boer, M; Nelson, K E; Khamboonruang, C

    1995-05-01

    The first confirmed case of human immunodeficiency virus (HIV) infection in Thailand was that of a Thai male commercial sex worker (CSW) in 1985. Since that time, this disease has manifested itself among injecting drug users, female sex workers, and in the general heterosexual and homosexual population. This paper reports the findings of a 5-year Thai study in which 1172 male CSWs were studied at least once. The purpose of the study was to identify the prevalence, incidence, and risk behaviors of CSWs regarding HIV and syphilis. The HIV prevalence increased from 1.4% in 1989 to 20.1% by 1993. Overall, the HIV prevalence for the 5-year period was statistically significant at 16.6%. Syphilis for this same period was 7.6% HIV infections were confirmed using enzyme-linked immunosorbent assay (ELISA). Multivariate analysis was calculated using multiple logistic regression. All CSWs in this study were provided with HIV pre-test counseling, were subjected to HIV and syphilis serology, were given condoms, and were provided with a referral for post-test counseling. Of the 1172 men seen, 219 (18.6%) were seen more than once. 27 cases of HIV infection were confirmed in the latter group (12.3%). Heterosexual men were found to be at lower risk of contracting an HIV infection than homosexual men. PMID:7639978

  17. Gentamicin Induced Nephrotoxicity: The Role of Sex Hormones in Gonadectomized Male and Female Rats

    PubMed Central

    Eshraghi-Jazi, Fatemeh; Talebi, Ardeshir; Moslemi, Fatemeh

    2016-01-01

    Background. Gentamicin (GM) induced nephrotoxicity may be sex hormones related. The effects of sex hormones on GM induced nephrotoxicity in gonadectomized rats were investigated. Methods. Ovariectomized rats received 0.25, 0.5, or 1 mg/kg/week of estradiol (ES) alone or accompanied with 10 mg/kg/week of progesterone (Pro) for two weeks followed by GM (100 mg/kg/day) for 9 days. Castrated rats were also treated with 10, 50, or 100 mg/kg/week of testosterone (TS) for two weeks and then received GM. In addition, a single castrated group received 0.25 mg/kg/week of ES plus GM. Results. GM increased the serum levels of blood urea nitrogen (BUN) and creatinine (Cr) and kidney tissue damage score (KTDS) (P < 0.05). TS had no effect on the serum levels of BUN and Cr and KTDS, while low dose of ES intensified these parameters in male (P < 0.05). ES (0.5 mg/kg) without Pro ameliorated KTDS in female (P < 0.05) while ES (1 mg/kg) with or without Pro exacerbated the BUN values and Cr values, KTDS, and body weight loss (P < 0.05). Conclusion. ES (0.5 mg/kg) without Pro ameliorated kidney damage induced by GM in female while neither TS nor ES had beneficial effect on nephrotoxicity induced by GM in male, although ES aggravated it. PMID:27213082

  18. 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

  19. Markers of sexually transmitted diseases in seminal fluid of male clients of female sex workers.

    PubMed Central

    Worm, A M; Lauritzen, E; Jensen, I P; Jensen, J S; Christiansen, C B

    1997-01-01

    OBJECTIVES: To screen for certain STD markers in a group of male clients of female sex workers. METHOD: Condoms with seminal fluid were collected at 10 "massage parlours" in Copenhagen. The seminal fluid samples were examined for HIV antibodies, markers of hepatitis B virus (HBV), Chlamydia trachomatis, and Mycoplasma genitalium. RESULTS: All samples (n = 332) were negative for HIV antibodies. Out of 327 samples examined for HBV markers 32 (9.8%) were positive for HBV core antibodies, one of which was also positive for HBV antigen. C trachomatis could be demonstrated in six out of 122 (4.9%) samples and M genitalium in one out of 122 samples. CONCLUSIONS: The finding of a C trachomatis prevalence of 4.9% is considerable higher than expected in men with a presumed age of 35-55 years. The demonstration of a prevalence of HBV markers of 9.8% indicates that these clients have an increased risk of HBV infection, a finding that further consolidates the recommendation of HBV vaccination of sex workers. As shown in this study, STD transmission in commercial sex may also have the client as the source. PMID:9389951

  20. High Adult Sex Ratios and Risky Sexual Behaviors: A Systematic Review

    PubMed Central

    Bien, Cedric H.; Cai, Yong; Emch, Michael E.; Parish, William; Tucker, Joseph D.

    2013-01-01

    Background Thirty-four countries worldwide have abnormally high sex ratios (>102 men per 100 women), resulting in over 100 million missing women. Widespread sex selective abortion, neglect of young girls leading to premature mortality, and gendered migration have contributed to these persistent and increasing distortions. Abnormally high adult sex ratios in communities may drive sexually transmitted disease (STD) spread where women are missing and men cannot find stable partners. We systematically reviewed evidence on the association between high community sex ratios and individual sexual behaviors. Methods and Findings Seven databases (PubMed, Web of Science, Embase, Scopus, The Cochrane Database of Systematic Reviews, Sociological Abstracts, and PopLINE) were searched without restrictions on time or location. We followed PRISMA guidelines and evaluated quality according to STROBE criteria. 1093 citations were identified and six studies describing 57,054 individuals were included for review. All six studies showed an association between high community sex ratios and individual sexual risk behaviors. In high sex ratio communities, women were more likely to have multiple sex partners and men were more likely to delay first sexual intercourse and purchase sex. Only two studies included STD outcomes. Conclusions High community sex ratios were associated with increased individual sexual risk behavior among both men and women. However, none of the studies examined unprotected sex or appropriately adjusted for gendered migration. Further studies are needed to understand the effect of community sex ratios on sexual health and to inform comprehensive STD control interventions. PMID:23967223

  1. Sex-specific patterns and deregulation of endocrine pathways in the gene expression profiles of Bangladeshi adults exposed to arsenic contaminated drinking water

    SciTech Connect

    Muñoz, Alexandra; Chervona, Yana; Hall, Megan; Kluz, Thomas; Gamble, Mary V.; Costa, Max

    2015-05-01

    Arsenic contamination of drinking water occurs globally and is associated with numerous diseases including skin, lung and bladder cancers, and cardiovascular disease. Recent research indicates that arsenic may be an endocrine disruptor. This study was conducted to evaluate the nature of gene expression changes among males and females exposed to arsenic contaminated water in Bangladesh at high and low doses. Twenty-nine (55% male) Bangladeshi adults with water arsenic exposure ranging from 50 to 1000 μg/L were selected from the Folic Acid Creatinine Trial. RNA was extracted from peripheral blood mononuclear cells for gene expression profiling using Affymetrix 1.0 ST arrays. Differentially expressed genes were assessed between high and low exposure groups for males and females separately and findings were validated using quantitative real-time PCR. There were 534 and 645 differentially expressed genes (p < 0.05) in the peripheral blood mononuclear cells of males and females, respectively, when high and low water arsenic exposure groups were compared. Only 43 genes overlapped between the two sexes, with 29 changing in opposite directions. Despite the difference in gene sets both males and females exhibited common biological changes including deregulation of 17β-hydroxysteroid dehydrogenase enzymes, deregulation of genes downstream of Sp1 (specificity protein 1) transcription factor, and prediction of estrogen receptor alpha as a key hub in cardiovascular networks. Arsenic-exposed adults exhibit sex-specific gene expression profiles that implicate involvement of the endocrine system. Due to arsenic's possible role as an endocrine disruptor, exposure thresholds for arsenic may require different parameters for males and females. - Highlights: • Males and females exhibit unique gene expression changes in response to arsenic. • Only 23 genes are common among the differentially expressed genes for the sexes. • Male and female gene lists exhibit common biological

  2. 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

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

    PubMed Central

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

    2014-01-01

    In Vietnam, there is an emerging HIV epidemic among men who have sex with men (MSM). Male sex workers (MSWs) 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 utilized 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 minimize exposure to stigma, economic imperatives and familial responsibilities. PMID:25555192

  4. Effects of psychostimulants on social interaction in adult male rats.

    PubMed

    Šlamberová, Romana; Mikulecká, Anna; Macúchová, Eva; Hrebíčková, Ivana; Ševčíková, Mária; Nohejlová, Kateryna; Pometlová, Marie

    2015-12-01

    Psychostimulants are known to have a huge impact on different forms of social behaviour. The aim of the present study was to compare the effects of three different psychostimulants [amphetamine, cocaine and 3,4 methylenedimethoxyamphetamine (MDMA)] on social interaction (SI) in adult male rats. The SI test was performed in a familiar arena and under low-stress environmental conditions. Experimental animals received amphetamine (0.5, 1.0, 1.5 mg/kg), cocaine (0.5, 1.0, 1.5, 2.5, 5.0, 10.0 mg/kg) or MDMA (2.5, 5.0, 10 mg/kg) and control animals received saline (1 ml/kg) 45 min before the SI test. Time spent in SI (individual patterns of social behaviour) and nonsocial activities (locomotion and rearing) were video recorded and then analysed offline, with the following results: (a) all doses of amphetamine decreased SI. Specifically, all doses of amphetamine decreased mutual sniffing, and the higher doses also decreased allo-grooming and following behaviours. (b) The higher doses of cocaine decreased SI, especially mutual sniffing, allo-grooming and climbing over. Cocaine at the dose of 5.0 mg/kg increased genital investigation compared with lower doses. (c) All doses of MDMA decreased mutual sniffing and climbing over; the two higher doses decreased allo-grooming behaviour, and only the highest dose decreased following. The two higher doses of amphetamine and all the doses of MDMA increased locomotion and rearing; cocaine did not affect locomotion, but increased rearing at higher doses. In conclusion, the results confirm the well-known finding that psychostimulants suppress SI, but also show novel differences in the effects of psychostimulants on specific patterns of SI. PMID:26061354

  5. Spectrographic analysis of the ultrasonic vocalisations of adult male and female BALB/c mice

    NASA Astrophysics Data System (ADS)

    Gourbal, Benjamin E. F.; Barthelemy, Mathieu; Petit, Gilles; Gabrion, Claude

    In this study, a spectrographic analysis was designed to improve the description of the shape, the modulations, the rate, length and frequencies of BALB/c mouse calls in different behavioural situations. Male and female calls emitted during investigation of cages with clean bedding, soiled with male or female bedding, and during same-sex encounters, were recorded and described. BALB/c male mice uttered different types of vocalisations both when investigating counterpart odour cues and when interacting with same-sex counterparts. BALB/c female mice vocalised solely during same-sex counterpart encounters and it appeared that calls were uttered mainly by the resident females. Male and female mice present a complex array of calls, which seem to be linked to particular behavioural situations. Further studies using this technology may help to improve our understanding of the role of vocal communication in natural rodent populations.

  6. 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

  7. Sex role identity in young adults: its parental antecedents and relation to ego development.

    PubMed

    Costos, D

    1986-03-01

    This study, inspired by Block's (1973) work, was designed to enable one to examine how ego development and socialization experience interact in relation to sex role identity. Sex role identity was measured via the Bem Sex Role Inventory, and socialization practices were measured via the Block Child-Rearing Practices Report. Both measures were scaled so as to yield scores on agency, communion, and androgyny. Ego development was assessed via Loevinger's Sentence Completion Test of Ego Development. The sample consisted of 120 young adult men and women, married and single. Analyses revealed that the predictive power of the variables differed by sex. Ego development was predictive of sex role identity in men but not women, whereas socialization practices were predictive of sex role identity in women but not men. The results were seen as supporting Chodorow's (1974) position regarding the differing socialization experiences of men and women. PMID:3701594

  8. 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

  9. Organizational influence of the postnatal testosterone surge on the circadian rhythm of core body temperature of adult male rats.

    PubMed

    Zuloaga, Damian G; McGivern, Robert F; Handa, Robert J

    2009-05-01

    The suprachiasmatic nucleus (SCN) of the hypothalamus coordinates physiological and behavioral circadian rhythms such as activity, body temperature, and hormone secretion. Circadian rhythms coordinated by the SCN often show sex differences arising from both organizational and activational effects of gonadal hormones. In males, little is known about the organizational role of testosterone on the circadian regulation of core body temperature (CBT) in adulthood. To explore this, we castrated or sham-operated male rats on the day of birth, and at 4 months of age, implanted them with transmitters that measured CBT rhythms under a 12:12 light/dark cycle. This study revealed a significantly earlier rise in CBT during the light phase in neonatally castrated males. Subsequently, we found that treating neonatally castrated males with testosterone propionate (TP) in adulthood did not reverse the effect of neonatal castration, thus indicating an organizational role for testosterone. In contrast, a single injection of TP at the time of neonatal surgery, to mimic the postnatal surge of testosterone, coupled with TP treatment in adulthood, normalized the circadian rise in CBT. In a final study we examined CBT circadian rhythms in intact adult male and female rats and detected no differences in the rise of CBT during the light phase, although there was a greater overall elevation in female CBT. Together, results of these studies reveal an early organizational role of testosterone in males on the timing of the circadian rise of CBT, a difference that does not appear to reflect "defeminization". PMID:19272357

  10. Prevalence and associated factors of condomless receptive anal intercourse with male clients among transgender women sex workers in Shenyang, China

    PubMed Central

    Cai, Yong; Wang, Zixin; Lau, Joseph TF; Li, Jinghua; Ma, Tiecheng; Liu, Yan

    2016-01-01

    Introduction Globally, transgender women sex workers have a high prevalence of HIV and condomless receptive anal intercourse with male clients (CRAIMC). We investigated the prevalence of CRAIMC and factors associated with CRAIMC among transgender women sex workers in China. Methods In 2014, we anonymously interviewed 220 transgender women sex workers face to face in Shenyang, China. Those who self-reported as HIV negative or as having unknown HIV serostatus were invited to take up free, anonymous HIV rapid testing (n=183); 90 did so. Using CRAIMC in the last month as the dependent variable, three types of associated factors were investigated, in addition to background factors: feminizing medical interventions, sex work and perceptions related to condom use. Univariate and multiple logistic regression models were fitted. Results Of the participants, 16.8% self-reported as HIV positive and 9.1% were detected to be HIV positive through free HIV testing; 26.8% had had CRAIMC in the last month, 45.5% had performed sex work in other Chinese cities (last year), and 23.2% had had condomless anal intercourse with men who were non-clients. In the adjusted analysis, significant factors associated with CRAIMC (last month) included the following: 1) any feminizing medical intervention performed (adjusted odds ratio, AOR: 2.22); 2) sex-work-related factors, including recruitment of male clients most often at hotels (AOR: 5.02) and charge per episode of transactional sex (201 to 400 RMB, AOR: 0.27; reference group: ≤100 RMB); and 3) perceptions related to condom use, including perceived transgender identity's impact on condomless sex such as wearing feminine attire, concern about exposing their status as a transgender woman to male clients (AOR: 1.20) and perceived self-efficacy of consistent condom use with male clients (AOR: 0.56). Perceived self-efficacy of consistent condom use with male clients fully mediated the association between perceived transgender identity's impact

  11. Baseline sacroiliac joint magnetic resonance imaging abnormalities and male sex predict the development of radiographic sacroiliitis.

    PubMed

    Akar, Servet; Isik, Sibel; Birlik, Bilge; Solmaz, Dilek; Sari, Ismail; Onen, Fatos; Akkoc, Nurullah

    2013-10-01

    We evaluated the relationship between the baseline sacroiliac joint (SIJ) magnetic resonance imaging (MRI) findings and the development of radiographic sacroiliitis and tested their prognostic significance in cases of ankylosing spondylitis. Patients who had undergone an SIJ MRI at the rheumatology department were identified. Individuals for whom pelvic X-rays were available after at least 1 year of MRI were included in the analysis. All radiographs and MRI examinations were scored by two independent readers. Medical records of the patients were reviewed to obtain potentially relevant demographic and clinical data. We identified 1,069 SIJ MRIs, and 328 fulfilled our inclusion criteria. Reliability analysis revealed moderate to good inter- and intra-observer agreement. On presentation data, 14 cases were excluded because they had unequivocal radiographic sacroiliitis at baseline. After a mean of 34.8 months of follow-up, 24 patients developed radiographic sacroiliitis. The presence of active sacroiliitis (odds ratio (OR) 15.1) and structural lesions on MRI (OR 8.3), male sex (OR 4.7), fulfillment of Calin's inflammatory back pain criteria (P = 0.001), and total MRI activity score (P < 0.001) were found to be related to the development of radiographic sacroiliitis. By regression modeling, the presence of both active inflammatory and structural damage lesions on MRI and male sex were found to be predictive factors for the development of radiographic sacroiliitis. Our present results suggest that the occurrence of both active inflammatory and structural lesions in SIJs revealed by MRI is a significant risk factor for radiographic sacroiliitis, especially in male patients with early inflammatory back pain. PMID:23765093

  12. Transfer of cattle embryos produced with sex-sorted semen results in impaired pregnancy rate and increased male calf mortality.

    PubMed

    Mikkola, M; Andersson, M; Taponen, J

    2015-10-15

    This study investigated the pregnancy rate and calf mortality after transfer of embryos produced using sex-sorted semen. Data for 12,438 embryo transfers performed on dairy farms were analyzed. Of these, 10,697 embryos were produced using conventional semen (CONV embryos) and 1741 using sex-sorted semen from 97 bulls (SEX embryos), predominantly of Ayrshire and Holstein breeds. Of the CONV embryos, 27.4% were transferred fresh, whereas of the SEX embryos, 55.7% were fresh. Recipient attributes (breed, parity, number of previous breeding attempts, and interval from calving to transfer) were comparable for both embryo types, heifers representing 57.8% of recipients in the CONV group and 54.8% in the SEX group. Recipients that were not artificially inseminated or did not undergo a new embryo transfer after the initial embryo transfer and had registered calving in fewer than 290 days after the transfer were considered pregnant. Pregnancy rate for recipients receiving CONV embryos was 44.1%, and for those receiving SEX embryos, it was 38.8%. The odds ratio for pregnancy in recipients receiving CONV embryos was 1.34 compared with SEX embryos (P < 0.001). The proportion of female calves was 49.6% and 92.3% in CONV and SEX groups, respectively. Overall, calf mortality was comparable in both groups. Mortality was similar in CONV and SEX groups (6.6% and 7.7%, respectively) for female calves. For male calves, mortality was 9.2% in the CONV group but significantly higher, 16.0% (P < 0.05), in the SEX group. This study showed that transfer of embryos produced with sex-sorted semen decreased the pregnancy rate by about 12% compared with embryos produced using conventional semen. Mortality of male calves born from SEX embryos was higher than for those born from CONV embryos. PMID:26174034

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

    PubMed

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

    2009-01-01

    Demographic factors such as operational sex ratio (OSR) and local population density (LPD) are temporally and spatially dynamic in the natural environment but the influence of these variables on male mating success and the mechanisms behind it are still poorly understood and highly controversial. Here, we manipulated the OSR and LPD of a seed bug, Nysius huttoni, and carried out a series of mating trials to test how these variables affected male mating success. The two demographic factors had no significant interactions, suggesting that they affect male mating success independently in N. huttoni. In this species male mating success was significantly higher in both male- and female-biased OSR than in even OSR. It is suggested that, in male-biased OSR, the increased intensity of competition and interference does not result in lower male mating success; rather, males may make more effort in courting and females may have more chance to encounter better males, resulting in higher male mating success. In female-biased OSR, females may become less choosy and less likely to reject male mating attempt, leading to the higher male mating success. Lower male mating success in N. huttoni in high LPD may be due to increased interference between males and/or delayed female receptiveness for mating. OSR had a stronger effect on male mating success than LPD in N. huttoni, suggesting that OSR and LPD affect mating success in different ways and intensities. PMID:18839127

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

    NASA Astrophysics Data System (ADS)

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

    2009-01-01

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

  15. Unique sex chromosome systems in Ellobius: How do male XX chromosomes recombine and undergo pachytene chromatin inactivation?

    PubMed Central

    Matveevsky, Sergey; Bakloushinskaya, Irina; Kolomiets, Oxana

    2016-01-01

    Most mammalian species have heteromorphic sex chromosomes in males, except for a few enigmatic groups such as the mole voles Ellobius, which do not have the Y chromosome and Sry gene. The Ellobius (XX ♀♂) system of sex chromosomes has no analogues among other animals. The structure and meiotic behaviour of the two X chromosomes were investigated for males of the sibling species Ellobius talpinus and Ellobius tancrei. Their sex chromosomes, despite their identical G-structure, demonstrate short synaptic fragments and crossover-associated MLH1 foci in both telomeric regions only. The chromatin undergoes modifications in the meiotic sex chromosomes. SUMO-1 marks a small nucleolus-like body of the meiotic XX. ATR and ubiH2A are localized in the asynaptic area and the histone γH2AFX covers the entire XX bivalent. The distribution of some markers of chromatin inactivation differentiates sex chromosomes of mole voles from those of other mammals. Sex chromosomes of both studied species have identical recombination and meiotic inactivation patterns. In Ellobius, similar chromosome morphology masks the functional heteromorphism of the male sex chromosomes, which can be seen at meiosis. PMID:27425629

  16. Adolescent exposure to cocaine, amphetamine, and methylphenidate cross-sensitizes adults to methamphetamine with drug- and sex-specific effects.

    PubMed

    Shanks, Ryan A; Ross, Jordan M; Doyle, Hillary H; Helton, Amanda K; Picou, Brittany N; Schulz, Jordyn; Tavares, Chris; Bryant, Sarah; Dawson, Bryan L; Lloyd, Steven A

    2015-03-15

    The increasing availability, over-prescription, and misuse and abuse of ADHD psychostimulant medications in adolescent populations necessitates studies investigating the long-term effects of these drugs persisting into adulthood. Male and female C57Bl/6J mice were exposed to amphetamine (AMPH) (1.0 and 10 mg/kg), methylphenidate (MPD) (1.0 and 10 mg/kg), or cocaine (COC) (5.0 mg/kg) from postnatal day 22 to 31, which represents an early adolescent period. After an extended period of drug abstinence, adult mice were challenged with a subacute methamphetamine (METH) dose (0.5 mg/kg), to test the long-term effects of adolescent drug exposures on behavioral cross-sensitization using an open field chamber. There were no sex- or dose-specific effects on motor activity in adolescent, saline-treated controls. However, AMPH, MPD, and COC adolescent exposures induced cross-sensitization to a subacute METH dose in adulthood, which is a hallmark of addiction and a marker of long-lasting plastic changes in the brain. Of additional clinical importance, AMPH-exposed male mice demonstrated increased cross-sensitization to METH in contrast to the female-specific response observed in MPD-treated animals. There were no sex-specific effects after adolescent COC exposures. This study demonstrates differential drug, dose, and sex-specific alterations induced by early adolescent psychostimulant exposure, which leads to behavioral alterations that persist into adulthood. PMID:25496784

  17. Sex differences in autism: a resting-state fMRI investigation of functional brain connectivity in males and females.

    PubMed

    Alaerts, Kaat; Swinnen, Stephan P; Wenderoth, Nicole

    2016-06-01

    Autism spectrum disorders (ASD) are far more prevalent in males than in females. Little is known however about the differential neural expression of ASD in males and females. We used a resting-state fMRI-dataset comprising 42 males/42 females with ASD and 75 male/75 female typical-controls to examine whether autism-related alterations in intrinsic functional connectivity are similar or different in males and females, and particularly whether alterations reflect 'neural masculinization', as predicted by the Extreme Male Brain theory. Males and females showed a differential neural expression of ASD, characterized by highly consistent patterns of hypo-connectivity in males with ASD (compared to typical males), and hyper-connectivity in females with ASD (compared to typical females). Interestingly, patterns of hyper-connectivity in females with ASD reflected a shift towards the (high) connectivity levels seen in typical males (neural masculinization), whereas patterns of hypo-connectivity observed in males with ASD reflected a shift towards the (low) typical feminine connectivity patterns (neural feminization). Our data support the notion that ASD is a disorder of sexual differentiation rather than a disorder characterized by masculinization in both genders. Future work is needed to identify underlying factors such as sex hormonal alterations that drive these sex-specific neural expressions of ASD. PMID:26989195

  18. 1-Tridecene—male-produced sex pheromone of the tenebrionid beetle Parastizopus transgariepinus

    NASA Astrophysics Data System (ADS)

    Geiselhardt, Sven; Ockenfels, Peter; Peschke, Klaus

    2008-03-01

    Males of the genus Parastizopus (Coleoptera: Tenebrionidae) exhibit a special pheromone-emitting behaviour. They do a headstand, expose the aedeagus and remain in this posture for a few seconds. The pheromone emitted by P. transgariepinus was collected by solid-phase micro-extraction (100 μm 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 μg/male, respectively. Chemo-orientation experiments using a servosphere showed that 1 μg of 1-tridecene was attractive to females but not to males.

  19. Sex disparity in childhood and young adult acute myeloid leukemia (AML) survival: Evidence from US population data.

    PubMed

    Hossain, Md Jobayer; Xie, Li

    2015-12-01

    Sex variation has been persistently investigated in studies concerning acute myeloid leukemia (AML) survival outcomes but has not been fully explored among pediatric and young adult AML patients. We detected sex difference in the survival of AML patients diagnosed at ages 0-24 years and explored distinct effects of sex across subgroups of age at diagnosis, race-ethnicity and AML subtypes utilizing the United States Surveillance Epidemiology and End Results (SEER) population based dataset of 4865 patients diagnosed with AML between 1973 and 2012. Kaplan-Meier survival function, propensity scores and stratified Cox proportional hazards regression were used for data analyses. After controlling for other prognostic factors, females showed a significant survival advantage over their male counterparts, adjusted hazard ratio (aHR, 95% confidence interval (CI): 1.09, 1.00-1.18). Compared to females, male patients had substantially increased risk of mortality in the following subgroups of: ages 20-24 years at diagnosis (aHR1.30), Caucasian (1.14), acute promyelocytic leukemia (APL) (1.35), acute erythroid leukemia (AEL) (1.39), AML with inv(16)(p13.1q22) (2.57), AML with minimum differentiation (1.47); and had substantially decreased aHR in AML t(9;11)(p22;q23) (0.57) and AML with maturation (0.82). Overall, females demonstrated increased survival over males and this disparity was considerably large in patients ages 20-24 years at diagnosis, Caucasians, and in AML subtypes of AML inv(16), APL and AEL. In contrast, males with AML t(9;11)(p22;q23), AML with maturation and age at diagnosis of 10-14 years showed survival benefit. Further investigations are needed to detect the biological processes influencing the mechanisms of these interactions. PMID:26520618

  20. Sex-specific effects of bisphenol-A on memory and synaptic structural modification in hippocampus of adult mice.

    PubMed

    Xu, Xiaohong; Liu, Xingyi; Zhang, Qin; Zhang, Guangxia; Lu, Yingjun; Ruan, Qin; Dong, Fangni; Yang, Yanling

    2013-05-01

    Humans are routinely exposed to low levels of bisphenol A (BPA), a synthetic xenoestrogen widely used in the production of polycarbonate plastics. The effects of long-term exposure to BPA on memory and modification of synaptic structure in hippocampus of adult mice were investigated in the present study. The adult mice were exposed to BPA (0.4, 4, and 40 mg/kg/day) or arachis oil for 12 weeks. In open field test, BPA at 0.4, 4, or 40 mg/kg/day increased the frequency of rearing and time in the central area of the males, while BPA at 0.4 mg/kg/day reduced the frequency of rearing in the females. Exposure to BPA (0.4 or 40 mg/kg/day) extended the average escape pathlength to the hidden platform in Morris water maze task and shortened the step-down latency 24 h after footshock of the males, but no changes were found in the females for these measures. Meanwhile, BPA induced a reduced numeric synaptic density and a negative effect on the structural parameters of synaptic interface, including an enlarged synaptic cleft and the reduced length of active zone and PSD thickness, in the hippocampus of the male mice. Western blot analyses further indicated that BPA down-regulated expressions of synaptic proteins (synapsin I and PSD-95) and synaptic NMDA receptor subunit NR1 and AMPA receptor subunit GluR1 in the hippocampus of the males. These results suggest that long-term exposure to low levels of BPA in adulthood sex-specifically impaired spatial and passive avoidance memory of mice. These effects may be associated with the higher susceptibility of the hippocampal synaptic plasticity processes, such as remodeling of spinal synapses and the expressions of synaptic proteins (e.g. synapsin I and PSD-95) and NMDA and AMPA receptors, to BPA in the adult male mice. PMID:23523742

  1. Arterial Compliance and Autonomic Functions in Adult Male Smokers

    PubMed Central

    Saxena, Yogesh; Gupta, Rani

    2016-01-01

    Introduction Smoking is known to augment sympathetic activity and may lead to increased arterial stiffness. Several studies have reported association of increased sympathetic activity and arterial stiffness to cardiovascular risks among smokers. Pulse Wave Velocity (PWV) of peripheral arteries, instead of aorta can be used as a non-invasive indicator of arterial stiffness. Aim To measure non-invasively, the autonomic functions and peripheral arterial stiffness in smokers, and to find out whether the aforementioned factors are modified by the level of physical activity in these smokers. Materials and Methods This cross-sectional analytical study was conducted in the Department of Physiology, HIMS, Dehradun, over a period of 12 months (2013-2014) on 100 adult males (20-40 years); 50 smokers and 50 non-smokers. The parameters analysed include relevant anthropometric and cardiovascular parameters, Pulse Wave Velocity (PWV), sustained Hand Grip Test (HGT) and Heart Rate Variability (HRV) domains. Data interpretation and analysis was carried out using SPSS 17.0. Comparison of the above mentioned parameters amongst groups was done with unpaired t-test. The relationship of pack-years & physical activity with vascular functions was assessed by Pearson’s correlation. Interaction of various grades of smoking and physical activity with Cardiovascular System (CVS) parameters was assessed by one-way ANOVA. Results Smokers had higher values of PWV (5.7±0.5m/s) as compared to non-smokers (4.8±0.4m/s) (p<0.001). ΔDBP during HGT was lower (7±3.18mmHg) among smokers as compared to non-smokers (19.4±3.5mmHg) (p<0.001). Smoking (pack-years) was positively related to PWV (r= .03) but showed a weak negative relationship with change in Diastolic Blood Pressure (ΔDBP) (r= -0.084, p=0.56) showing that, more the frequency of smoking, the more was arterial stiffening and the lesser was the sympathetic response to the HGT. The smokers had significantly higher sympathetic activity; Low

  2. Counseling Adult Sex Offenders: Unique Challenges and Treatment Paradigms.

    ERIC Educational Resources Information Center

    Priest, Ronnie; Smith, Annalee

    1992-01-01

    Reviews current definitions and research literature related to characteristics of adults who sexually victimize children. Presents discussion of pedophilia as a sexual deviation. Examines treatment issues that may confront counselors engaged in treating adults who sexually victimize children and discusses implications for practitioners. (Author/NB)

  3. Risky Sex Behavior and Substance Use among Young Adults.

    ERIC Educational Resources Information Center

    Staton, Michele; Leukefeld, Carl; Logan, T. K.; Zimmerman, Rick; Lynam, Donald; Milich, Richard; Martin, Catherine; McClanahan, Karen; Clayton, Richard

    1999-01-01

    Examines the relationship between substance use during adolescence and HIV risk behavior among young adults ages 19 to 21 with and without a college education. Results indicate that increased use of alcohol and marijuana at younger ages is related to riskier sexual activity as well as increased use of alcohol and marijuana as young adults.…

  4. 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

  5. Stress-induced oxytocin release and oxytocin cell number and size in prepubertal and adult male and female rats.

    PubMed

    Minhas, Sumeet; Liu, Clarissa; Galdamez, Josselyn; So, Veronica M; Romeo, Russell D

    2016-08-01

    Studies indicate that adolescent exposure to stress is a potent environmental factor that contributes to psychological and physiological disorders, though the mechanisms that mediate these dysfunctions are not well understood. Periadolescent animals display greater stress-induced hypothalamic-pituitary-adrenal (HPA) axis responses than adults, which may contribute to these vulnerabilities. In addition to the HPA axis, the hypothalamo-neurohypophyseal tract (HNT) is also activated in response to stress. In adults, stress activates this system resulting in secretion of oxytocin from neurons in the supraoptic (SON) and paraventricular (PVN) nuclei. However, it is currently unknown whether a similar or different response occurs in prepubertal animals. Given the influence of these hormones on a variety of emotional behaviors and physiological systems known to change as an animal transitions into adulthood, we investigated stress-induced HPA and HNT hormonal responses before and after stress, as well as the number and size of oxytocin-containing cells in the SON and PVN of prepubertal (30d) and adult (70d) male and female rats. Though we found the well-established protracted adrenocorticotropic hormone and corticosterone response in prepubertal males and females, only adult males and prepubertal females showed a significant stress-induced increase in plasma oxytocin levels. Moreover, though we found no pubertal changes in the number of oxytocin cells, we did find a pubertal-related increase in oxytocin somal size in both the SON and PVN of males and females. Taken together, these data indicate that neuroendocrine systems can show different patterns of stress reactivity before and after adolescent development and that these responses can be further modified by sex. Given the impact of these hormones on a variety of systems, it will be imperative to further explore these changes in hormonal stress reactivity and their role in adolescent health. PMID:26972154

  6. In Peru, reporting male sex partners imparts significant risk of incident HIV/STI infection: all men engaging in same-sex behavior need prevention services

    PubMed Central

    Konda, Kelika A.; Lescano, Andres G.; Celentano, David D.; Hall, Eric; Montano, Silvia M.; Kochel, Tadeusz J.; Coates, Thomas J.; Cáceres, Carlos F.

    2013-01-01

    Background Detailed information on the sexual behavior of bisexual, non-gay identified men and the relationship between same-sex behavior and HIV/STI incidence are limited. This study provides information on the sexual behavior with male partners of non-gay identified men in urban, coastal Peru and the relationship of this behavior with HIV/STI incidence. Methods We analyzed data from 2146 non-gay identified men with a baseline and then two years of annual follow-up, including detailed information on sexual behavior with up to 5 sex partners, to determine characteristics associated with bisexual behavior. Discrete time proportional hazards models were used to determine the effect of self-reported sex with men on subsequent HIV/STI incidence. Results Over the three study visits, sex with a man was reported by 18.9% of men, 90% of whom also reported sex with a female partner. At baseline, reported bisexual behavior was associated with other sexual risk behaviors such as exchanging sex for money and increased risk of HIV, HSV-2, and gonorrhea. The number of study visits in which recent sex with men was reported was positively correlated with risk of other sexual risk behaviors and incident HIV, HSV-2, and gonorrhea. Recent sex with a man was associated with increased HIV/STI incidence, HR 1.79 (95% CI 1.19 – 2.70), after adjusting for socio-demographics and other sexual risk behaviors. Conclusions Given the prevalence of recent sex with men and the relationship of this behavior with HIV/STI incidence, interventions with non-gay identified men who have sex with men and their partners are warranted. PMID:23965772

  7. Sex Differences in Responsiveness to Babies among Mature Adults.

    ERIC Educational Resources Information Center

    Feldman, S. Shirley; Nash, Sharon Churnin

    1979-01-01

    Interest in babies was assessed in 30 parents of adolescents, 28 parents whose grown children were no longer living at home, and 26 grandparents of an infant. Measures included responsivity to an unfamiliar baby in a waiting room situation, interest in pictures of babies, and a sex-role self-concept inventory. (JMB)

  8. Family Experiences of Young Adult Sex Offender Registration

    ERIC Educational Resources Information Center

    Comartin, Erin B.; Kernsmith, Poco D.; Miles, Bart W.

    2010-01-01

    Since 1994, policies have been instituted throughout the United States that require sex offenders to register their personal information with law enforcement officials (Jacob Wetterling Crimes against Children and Sexually Violent Offender Registration Program, 1994). With the passage of additional laws, this information is now available to the…

  9. Changes in HIV Seroprevalence and Related Behaviors Among Male Injection Drug Users Who Do and Do Not Have Sex With Men: New York City, 1990–1999

    PubMed Central

    Maslow, Carey B.; Friedman, Samuel R.; Perlis, Theresa E.; Rockwell, Russell; Des Jarlais, Don C.

    2002-01-01

    Objectives. This study examined HIV prevalence and risk behaviors among male injection drug users (IDUs) who have sex with men and among other male IDUs. Methods. Male IDUs were interviewed and tested for HIV at a detoxification clinic during 1990 to 1994 and 1995 to 1999. Analyses compared male IDUs who do and do not have sex with men within and between periods. Results. Initially, HIV seroprevalence and risk behaviors were higher among IDUs who have sex with men. Seroprevalence (initially 60.5% vs 48.3%) declined approximately 15% in both groups, remaining higher among those who have sex with men. Generally, injection prevalence, but not sexual risk behaviors, declined. Conclusions. Male IDUs who have sex with men are more likely to engage in higher-risk behaviors and to be HIV infected. Improved intervention approaches for male IDUs who have sex with men are needed. (Am J Public Health. 2002;92:382–384) PMID:11867315

  10. Sex Chromosome-wide Transcriptional Suppression and Compensatory Cis-Regulatory Evolution Mediate Gene Expression in the Drosophila Male Germline.

    PubMed

    Landeen, Emily L; Muirhead, Christina A; Wright, Lori; Meiklejohn, Colin D; Presgraves, Daven C

    2016-07-01

    The evolution of heteromorphic sex chromosomes has repeatedly resulted in the evolution of sex chromosome-specific forms of regulation, including sex chromosome dosage compensation in the soma and meiotic sex chromosome inactivation in the germline. In the male germline of Drosophila melanogaster, a novel but poorly understood form of sex chromosome-specific transcriptional regulation occurs that is distinct from canonical sex chromosome dosage compensation or meiotic inactivation. Previous work shows that expression of reporter genes driven by testis-specific promoters is considerably lower-approximately 3-fold or more-for transgenes inserted into X chromosome versus autosome locations. Here we characterize this transcriptional suppression of X-linked genes in the male germline and its evolutionary consequences. Using transgenes and transpositions, we show that most endogenous X-linked genes, not just testis-specific ones, are transcriptionally suppressed several-fold specifically in the Drosophila male germline. In wild-type testes, this sex chromosome-wide transcriptional suppression is generally undetectable, being effectively compensated by the gene-by-gene evolutionary recruitment of strong promoters on the X chromosome. We identify and experimentally validate a promoter element sequence motif that is enriched upstream of the transcription start sites of hundreds of testis-expressed genes; evolutionarily conserved across species; associated with strong gene expression levels in testes; and overrepresented on the X chromosome. These findings show that the expression of X-linked genes in the Drosophila testes reflects a balance between chromosome-wide epigenetic transcriptional suppression and long-term compensatory adaptation by sex-linked genes. Our results have broad implications for the evolution of gene expression in the Drosophila male germline and for genome evolution. PMID:27404402

  11. Sex Chromosome-wide Transcriptional Suppression and Compensatory Cis-Regulatory Evolution Mediate Gene Expression in the Drosophila Male Germline

    PubMed Central

    Landeen, Emily L.; Muirhead, Christina A.; Meiklejohn, Colin D.; Presgraves, Daven C.

    2016-01-01

    The evolution of heteromorphic sex chromosomes has repeatedly resulted in the evolution of sex chromosome-specific forms of regulation, including sex chromosome dosage compensation in the soma and meiotic sex chromosome inactivation in the germline. In the male germline of Drosophila melanogaster, a novel but poorly understood form of sex chromosome-specific transcriptional regulation occurs that is distinct from canonical sex chromosome dosage compensation or meiotic inactivation. Previous work shows that expression of reporter genes driven by testis-specific promoters is considerably lower—approximately 3-fold or more—for transgenes inserted into X chromosome versus autosome locations. Here we characterize this transcriptional suppression of X-linked genes in the male germline and its evolutionary consequences. Using transgenes and transpositions, we show that most endogenous X-linked genes, not just testis-specific ones, are transcriptionally suppressed several-fold specifically in the Drosophila male germline. In wild-type testes, this sex chromosome-wide transcriptional suppression is generally undetectable, being effectively compensated by the gene-by-gene evolutionary recruitment of strong promoters on the X chromosome. We identify and experimentally validate a promoter element sequence motif that is enriched upstream of the transcription start sites of hundreds of testis-expressed genes; evolutionarily conserved across species; associated with strong gene expression levels in testes; and overrepresented on the X chromosome. These findings show that the expression of X-linked genes in the Drosophila testes reflects a balance between chromosome-wide epigenetic transcriptional suppression and long-term compensatory adaptation by sex-linked genes. Our results have broad implications for the evolution of gene expression in the Drosophila male germline and for genome evolution. PMID:27404402

  12. Sexual practices, partner concurrency and high rates of sexually transmissible infections among male sex workers in three cities in Vietnam

    PubMed Central

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

    2015-01-01

    Background This paper examines sexual practices, partner concurrency and sexually transmissible infections (STI)/HIV infection among male sex workers (MSWs) in Vietnam. Methods Six hundred and fifty-four MSWs, aged 16–35 years, were recruited in Hanoi, Nha Trang and Ho Chi Minh City between 2009 and 2011. Survey measures included demographic characteristics, drug use, types of sexual partners and sexual practices. Subjects were screened for STIs, including HIV. Results MSWs in Ho Chi Minh City (33%) were more likely than those from the other two sites to be current users of one or more types of illegal drugs (P < 0.001). MSWs with both male and female elective partners (compared with other partnership types) were more likely to have anal sex with male client partners (P < 0.001), elective male partners (P = 0.045) and elective female partners (P = 0.025). At last sex with a male client partner, only 30% used a condom during anal intercourse. At last sex with an elective female partner, only 31% used a condom during vaginal sex and only 3% during anal sex. Although rates of HIV are low (4%), other STIs are high, including chlamydia (17%), gonorrhoea (29%) and human papillomavirus (33%). Most (57.3%) have never been tested for HIV and only 17% have ever disclosed to a healthcare provider that they have sex with men. Conclusions Complex patterns of sexual concurrency, coupled with high rates of STIs, signal the urgent need for health services interventions among MSWs, both to improve individual health outcomes and to reduce secondary STI/HIV transmission among sexual partner networks. PMID:25622225

  13. Assigning sex and reproductive stage to adult Lake Sturgeon using ultrasonography and common morphological measurements

    USGS Publications Warehouse

    Chiotti, Justin A.; Boase, James C.; Hondorp, Darryl W.; Briggs, Andrew S.

    2016-01-01

    Sex determination of fish species is difficult to assess when sexual dimorphism and gametes are not apparent. For threatened and endangered fish species, noninvasive techniques are needed when determining sex to minimize stress and the potential for mortality. We evaluated the use of a portable ultrasound unit to determine sex of Lake Sturgeon Acipenser fulvescens in the field. Ultrasound images were collected from 9 yellow-egg (F2, F3), 32 black-egg (F4, F5), and 107 fully developed male (M2) Lake Sturgeon. Two readers accurately assigned sex to 88–96% of fish, but accuracy varied in relation to maturity stage. Black-egg females and fully developed males were correctly identified for 89–100% of the fish sampled, while these two readers identified yellow-egg females only 33% and 67% of the time. Time spent collecting images ranged between 2 and 3 min once the user was comfortable with operating procedures. Discriminant analysis revealed the total length : girth ratio was a strong predictor of sex and maturity, correctly classifying 81% of black-egg females and 97% of the fully developed males. However, yellow-egg females were incorrectly classified on all occasions. This study shows the utility of using ultrasonography and a total length : girth ratio for sex determination of Lake Sturgeon in later reproductive stages around the spawning season.

  14. The sun, moon, wind, and biological imperative-shaping contrasting wintertime migration and foraging strategies of adult male and female northern fur seals (Callorhinus ursinus).

    PubMed

    Sterling, Jeremy T; Springer, Alan M; Iverson, Sara J; Johnson, Shawn P; Pelland, Noel A; Johnson, Devin S; Lea, Mary-Anne; Bond, Nicholas A

    2014-01-01

    Adult male and female northern fur seals (Callorhinus ursinus) are sexually segregated in different regions of the North Pacific Ocean and Bering Sea during their winter migration. Explanations for this involve interplay between physiology, predator-prey dynamics, and ecosystem characteristics, however possible mechanisms lack empirical support. To investigate factors influencing the winter ecology of both sexes, we deployed five satellite-linked conductivity, temperature, and depth data loggers on adult males, and six satellite-linked depth data loggers and four satellite transmitters on adult females from St. Paul Island (Bering Sea, Alaska, USA) in October 2009. Males and females migrated to different regions of the North Pacific Ocean: males wintered in the Bering Sea and northern North Pacific Ocean, while females migrated to the Gulf of Alaska and California Current. Horizontal and vertical movement behaviors of both sexes were influenced by wind speed, season, light (sun and moon), and the ecosystem they occupied, although the expression of the behaviors differed between sexes. Male dive depths were aligned with the depth of the mixed layer during daylight periods and we suspect this was the case for females upon their arrival to the California Current. We suggest that females, because of their smaller size and physiological limitations, must avoid severe winters typical of the northern North Pacific Ocean and Bering Sea and migrate long distances to areas of more benign environmental conditions and where prey is shallower and more accessible. In contrast, males can better tolerate often extreme winter ocean conditions and exploit prey at depth because of their greater size and physiological capabilities. We believe these contrasting winter behaviors 1) are a consequence of evolutionary selection for large size in males, important to the acquisition and defense of territories against rivals during the breeding season, and 2) ease environmental

  15. The Sun, Moon, Wind, and Biological Imperative–Shaping Contrasting Wintertime Migration and Foraging Strategies of Adult Male and Female Northern Fur Seals (Callorhinus ursinus)

    PubMed Central

    Sterling, Jeremy T; Springer, Alan M.; Iverson, Sara J.; Johnson, Shawn P.; Pelland, Noel A.; Johnson, Devin S.; Lea, Mary-Anne; Bond, Nicholas A.

    2014-01-01

    Adult male and female northern fur seals (Callorhinus ursinus) are sexually segregated in different regions of the North Pacific Ocean and Bering Sea during their winter migration. Explanations for this involve interplay between physiology, predator-prey dynamics, and ecosystem characteristics, however possible mechanisms lack empirical support. To investigate factors influencing the winter ecology of both sexes, we deployed five satellite-linked conductivity, temperature, and depth data loggers on adult males, and six satellite-linked depth data loggers and four satellite transmitters on adult females from St. Paul Island (Bering Sea, Alaska, USA) in October 2009. Males and females migrated to different regions of the North Pacific Ocean: males wintered in the Bering Sea and northern North Pacific Ocean, while females migrated to the Gulf of Alaska and California Current. Horizontal and vertical movement behaviors of both sexes were influenced by wind speed, season, light (sun and moon), and the ecosystem they occupied, although the expression of the behaviors differed between sexes. Male dive depths were aligned with the depth of the mixed layer during daylight periods and we suspect this was the case for females upon their arrival to the California Current. We suggest that females, because of their smaller size and physiological limitations, must avoid severe winters typical of the northern North Pacific Ocean and Bering Sea and migrate long distances to areas of more benign environmental conditions and where prey is shallower and more accessible. In contrast, males can better tolerate often extreme winter ocean conditions and exploit prey at depth because of their greater size and physiological capabilities. We believe these contrasting winter behaviors 1) are a consequence of evolutionary selection for large size in males, important to the acquisition and defense of territories against rivals during the breeding season, and 2) ease environmental

  16. Do prenatally methamphetamine-exposed adult male rats display general predisposition to drug abuse in the conditioned place preference test?

    PubMed

    Šlamberová, R; Pometlová, M; Schutová, B; Hrubá, L; Macúchová, E; Nová, E; Rokyta, R

    2012-01-01

    Drug abuse of pregnant women is a growing problem. The effect of prenatal drug exposure may have devastating effect on development of the offsprings that may be long-term or even permanent. One of the most common drug abused by pregnant women is methamphetamine (MA), which is also the most frequently abused illicit drug in the Czech Republic. Our previous studies demonstrated that prenatal MA exposure alters behavior, cognition, pain and seizures in adult rats in sex-specific manner. Our most recent studies demonstrate that prenatal MA exposure makes adult rats more sensitive to acute injection of the same or related drugs than their controls. The aim of the present study was to examine the effect of prenatal MA exposure on drug-seeking behavior of adult male rats tested in the Conditioned place preference (CPP). Adult male rats were divided to: prenatally MA-exposed (5 mg/kg daily for the entire prenatal period), prenatally saline-exposed (1 ml/kg of physiological saline) and controls (without maternal injections). The following drugs were used in the CPP test in adulthood: MA (5 mg/kg), amphetamine (5 mg/kg), cocaine (5 and 10 mg/kg), morphine (5 mg/kg), MDMA (5 mg/kg) and THC (2 mg/kg). Our data demonstrated that prenatally MA-exposed rats displayed higher amphetamine-seeking behavior than both controls. MA as well as morphine induced drug-seeking behavior of adult male rats, however this effect did not differ based on the prenatal MA exposure. In contrast, prenatal MA exposure induced rather tolerance to cocaine than sensitization after the conditioning in the CPP. MDMA and THC did not induce significant effects. Even though the present data did not fully confirmed our hypotheses, future studies are planned to test the drug-seeking behavior also in self-administration test. PMID:23130898

  17. Sex pheromone-induced chemolocation in the male American cockroach,Periplaneta americana.

    PubMed

    Hawkins, W A; Gorton, R E

    1982-01-01

    Males of the American cockroach,Periplaneta americana, have evolved an efficient search strategy enabling them to locate a source of sex pheromone in the absence of directional information derived from wind. Since these animals are able to utilize chemotaxis to orient almost directly to the source from 45-50 cm away, it is only necessary that they maximize their chances of getting within that range once they perceive the pheromone. They accomplish this by: (1) increasing their overall levels of activity and (2) initiating local search. In this way, they are able to cover a rather large area in a short period of time, i.e., before the source female changes location. If their paths take them to within 45 cm of the source, they are able to locate it soon thereafter. It is probable that very similar strategies are utilized by many other nonflying insects to locate sources of airborne odors. PMID:24414597

  18. 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

  19. Polymorphism, recombination, and mutations in HIV type 1 gag-infecting Peruvian male sex workers.

    PubMed

    Yabar, Carlos Augusto; Salvatierra, Javier; Quijano, Eberth

    2008-11-01

    HIV genetic diversity in female sex workers (FSW) has been previously described in Peru; however this information is not yet available for male sex workers (MSW). Therefore, purified peripheral blood mononuclear cell DNA from 147 HIV-infected subjects identified as MSW and FSW was used to amplify a 460-bp fragment corresponding to the p24-p7 region of the gag gene. The PCR product was digested with restriction enzymes to identify genetic polymorphism. Later, a random group of samples (n = 19) was sequenced to perform phylogenetic analysis, intragenic recombination analysis, and deleterious mutations leading to a nonfunctional protein in conservative regions of the Gag protein. RFLP analysis revealed 11 genetic variants for AluI and five for MspI. A group of nonsex workers (NSW) used for comparison showed different RFLP genetic variant distributions. Of interest, nine cases of mixed genetic variants were observed for MSW, one case for FSW, and none for NSW. Phylogenetic analysis revealed that all HIV-1 species were subtype B. Intragenic recombination analysis showed a B/C recombination case from an FSW (boostrap = 1000; p value < 0.05). Of interest, deleterious mutations were observed in three cases of conservative D2 zinc domains for Gag 3/19 and one case of the high homology region (1/19). This study shows that gag of HIV circulating from MSW has high genetic polymorphism involving deleterious mutations in conserved domains from the p24-p7 gag region. PMID:19000025

  20. Love, Trust, and HIV Risk Among Female Sex Workers and Their Intimate Male Partners

    PubMed Central

    Bazzi, Angela Robertson; Martinez, Gustavo; Rangel, M. Gudelia; Ulibarri, Monica D.; Fergus, Kirkpatrick B.; Amaro, Hortensia; Strathdee, Steffanie A.

    2015-01-01

    Objectives. We examined correlates of love and trust among female sex workers and their noncommercial male partners along the Mexico–US border. Methods. From 2011 to 2012, 322 partners in Tijuana and Ciudad Juárez, Mexico, completed assessments of love and trust. Cross-sectional dyadic regression analyses identified associations of relationship characteristics and HIV risk behaviors with love and trust. Results. Within 161 couples, love and trust scores were moderately high (median 70/95 and 29/40 points, respectively) and correlated with relationship satisfaction. In regression analyses of HIV risk factors, men and women who used methamphetamine reported lower love scores, whereas women who used heroin reported slightly higher love. In an alternate model, men with concurrent sexual partners had lower love scores. For both partners, relationship conflict was associated with lower trust. Conclusions. Love and trust are associated with relationship quality, sexual risk, and drug use patterns that shape intimate partners’ HIV risk. HIV interventions should consider the emotional quality of sex workers’ intimate relationships. PMID:26066947

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

    PubMed

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

    2012-10-01

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

  2. The attractivity of the female sex pheromone ofPeriplaneta americana and its components for conspecific males and males ofPeriplaneta australasiae in the field.

    PubMed

    Waldow, U; Sass, H

    1984-07-01

    The attractivity of virgin female odors of the American cockroach was examined in field experiments. Crude extracts of the female odor, the isolated sex pheromone fractions, periplanone-A and periplanone-B, and other compounds obtained during the isolation served as stimulants. An extract of male odors, obtained by identical collection methods, was used as a control. Males ofPeriplaneta americana were attracted by the crude extract and periplanone-B; males of the sympatric species,P. Australasiae, by periplanone-A. Experiments in which these components were presented subsequently and as mixtures indicate that, under certain conditions, periplanone-A may also function as an attracting substance forP. americana males and that periplanone-B and possibly some other components act as an inhibitor for males ofP. australasiae. PMID:24318844

  3. Chronic neonatal nicotine exposure increases excitation in the young adult rat hippocampus in a sex-dependent manner.

    PubMed

    Damborsky, Joanne C; Griffith, William H; Winzer-Serhan, Ursula H

    2012-01-01

    Smoking during pregnancy exposes the fetus to nicotine, resulting in nicotine-stimulated neurotransmitter release. Recent evidence suggests that the hippocampus develops differently in males and females with delayed maturation in males. We show that chronic nicotine exposure during the first postnatal week has sex-specific long-term effects. Neonatal rat pups were chronically treated with nicotine (6mg/kg/day) (CNN) from postnatal day 1 to 7 or milk only (Controls), and hippocampal slices were prepared from Control- and CNN-treated young adults. Field excitatory postsynaptic potentials (fEPSPs) or population spikes (PSs) were recorded from the CA1 hippocampus following CA1 s. radiatum stimulation. Input/Output curves constructed from fEPSP data indicated that CNN-males, but not females, had significantly increased excitatory responses compared to Controls (p<0.05, n=10 Con, n=11 CNN). Long-term potentiation (LTP) was not significantly changed by CNN. In the presence of bicuculline, which blocks inhibitory GABA(A) receptors, an epileptiform burst consisting of a series of PSs was evoked. The amplitude of the first PS was significantly larger in CNN-males and females compared to Controls (males: p<0.01, n=8 Con, n=8 CNN; females: p<0.05, n=9 Con, n=7 CNN). Only CNN-males also had significantly larger second PSs (p<0.05, n=8 con, n=8 CNN). Epileptiform activity evoked by zero Mg(2+) incubation did not differ in amplitude or duration of bursts in CNN-males or females compared to Controls. These data indicate that neonatal nicotine exposure has long lasting effects and results in increased excitation within the CA1 hippocampus in adulthood, with males showing increased sensitivity to nicotine's effects. PMID:22119395

  4. 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

  5. Posttraumatic stress disorder and substance use disorder comorbidity in homeless adults: Prevalence, correlates, and sex differences.

    PubMed

    Torchalla, Iris; Strehlau, Verena; Li, Kathy; Aube Linden, Isabelle; Noel, Francois; Krausz, Michael

    2014-06-01

    Substance use disorders (SUDs) are highly prevalent in homeless populations, and rates are typically greater among males. Posttraumatic stress disorder (PTSD) is a common co-occurring condition among individuals with SUDs; however, little attention has been directed to examining this comorbidity in homeless populations. Although some studies indicate considerable sex differences among individuals with PTSD, it has also been suggested that sex differences in PTSD rates diminish in populations with severe SUDs. This cross-sectional study investigated SUD-PTSD comorbidity and its associations with indicators of psychosocial functioning in a sample of 500 homeless individuals from Canada. Sex-related patterns of SUD, PTSD, and their comorbidity were also examined. Males and females had similar SUD prevalence rates, but the rates of PTSD and PTSD-SUD comorbidity were higher in females. PTSD and sex were found to have significant main effects on suicidality, psychological distress, somatic symptoms, and incarceration among individuals with SUD. Sex also moderated the association of PTSD with suicide risk and psychological distress. Our results contradict assumptions that sex differences in PTSD rates attenuate in samples with severe SUDs. Organizations providing SUD treatment for homeless people should address PTSD as an integrated part of their services. SUD and integrated treatment programs may benefit from sex-specific components. PMID:23915373

  6. Determination of sex from an autopsy sample of adult hyoid bones.

    PubMed

    Mukhopadhyay, Partha Pratim

    2012-07-01

    Determination of sex is the first and crucial step in the process of identifying human remains in forensic casework. Sex determination from skeletal remains is well studied and an extensively documented subject. The hyoid bone, however, has drawn less attention in studies of this nature. The present study was designed to derive a model for the determination of sex from the adult hyoid in a sample of the Indian Bengali population using discriminant function analysis on 50 adult bones (38 men and 12 women). The following discriminant function was obtained: DF = 0.103W + 0.118AP + 0.130CR + 0.483AW + 0.117DR - 20.64. Overall, 90% of the cases could be correctly classified into the two sexes by means of five predictors (overall width, length of the greater cornu, anteroposterior length, width of the body of hyoid and the distance between the lesser cornua) in the model. Cross-validated results showed correct classification in 90% of the cases. The results of this preliminary study show that these variables contribute to discrimination between the two sexes in the study population. Sexing of the adult human hyoid bone is thus possible with reasonable accuracy using the discriminant function on a sample obtained from the same population. PMID:22427484

  7. The Black Male Urban Barbershop as a Sex-Role Socialization Setting.

    ERIC Educational Resources Information Center

    Franklin, Clyde W., II

    1985-01-01

    Participant observation found that the barbershop studies perpetuated sex-role stereotypes, encouraged sexist attitudes toward women and, in general, was a sex-role socialization setting that promoted sex-role inequality. (GC)

  8. The Reentry Adult College Student: An Exploration of the Black Male Experience

    ERIC Educational Resources Information Center

    Rosser-Mims, Dionne; Palmer, Glenn A.; Harroff, Pamela

    2014-01-01

    This chapter shares findings from a qualitative study on reentry adult Black males' postsecondary education experiences and identifies strategies to help this population matriculate through college and graduate.

  9. GONADAL STEROIDS REGULATED THE EXPRESSION OF GLIAL FIBRILLARY ACIDIC PROTEIN IN THE ADULT MALE RAT HIPPOCAMPUS

    EPA Science Inventory

    This study demonstrates that gonadal steroids (estradiol, testosterone, dihydrotestosterone) can inhibit the expression of glial fibrillary acidic protein and it MRNA in the adult male rat brain. esticular hormones may influence the activity of astrocytes in the intact and lesion...

  10. Sex-determining mechanism in Buergeria buergeri (Anura, Rhacophoridae). III. Does the ZZW triploid frog become female or male?

    PubMed

    Ohta, S; Sumida, M; Nishioka, M

    1999-02-15

    Both triploids and gynogenetic diploids (GDs) were produced to clarify the relationship between the sex-chromosome constitution and the expression of sex in the common bell-ring frog, Buergeria buergeri. The sex differentiation of triploids in B. buergeri is quite remarkable. Triploid frogs consisted of three sex genotypes, ZZZ, ZWW and ZZW. All ZZZ triploids were males, and all ZWW triploids were females. It is very interesting that half of the ZZW triploids became female, and the other half became male. The GD frogs consisted of two sex genotypes, ZW and ZZ, which did not differ from the controls in sex differentiation. Since the ratios of ZZ and ZW eggs were significantly different among female parents, it is assumed that most (approximately 80-90%) of the eggs made pre-reductional division in some females and post-reductional division in others during meiosis. It seems that ZW eggs were produced by the occurrence of recombination between the centromere and the sex-determining genes in B. buergeri. It was also found that the number of Z chromosomes in each cell of these triploids and GDs agreed with that of the nucleoli in each cell. PMID:9933938

  11. Differences in Movement Pattern and Detectability between Males and Females Influence How Common Sampling Methods Estimate Sex Ratio

    PubMed Central

    Rodrigues, João Fabrício Mota; Coelho, Marco Túlio Pacheco

    2016-01-01

    Sampling the biodiversity is an essential step for conservation, and understanding the efficiency of sampling methods allows us to estimate the quality of our biodiversity data. Sex ratio is an important population characteristic, but until now, no study has evaluated how efficient are the sampling methods commonly used in biodiversity surveys in estimating the sex ratio of populations. We used a virtual ecologist approach to investigate whether active and passive capture methods are able to accurately sample a population’s sex ratio and whether differences in movement pattern and detectability between males and females produce biased estimates of sex-ratios when using these methods. Our simulation allowed the recognition of individuals, similar to mark-recapture studies. We found that differences in both movement patterns and detectability between males and females produce biased estimates of sex ratios. However, increasing the sampling effort or the number of sampling days improves the ability of passive or active capture methods to properly sample sex ratio. Thus, prior knowledge regarding movement patterns and detectability for species is important information to guide field studies aiming to understand sex ratio related patterns. PMID:27441554

  12. Experimentally induced hyperthyroidism influences oxidant and antioxidant status and impairs male gonadal functions in adult rats.

    PubMed

    Asker, M E; Hassan, W A; El-Kashlan, A M

    2015-08-01

    The objective of the present experiment was to study the effect of hyperthyroidism on male gonadal functions and oxidant/antioxidant biomarkers in testis of adult rats. Induction of hyperthyroidism by L-thyroxine (L-T4, 300 μg kg(-1) body weight) treatment once daily for 3 or 8 weeks caused a decrease in body weight gain as well as in absolute genital sex organs weight. The epididymal sperm counts and their motility were significantly decreased in a time-dependent manner following L-T4 treatment. Significant decline in serum levels of luteinising hormone, follicle stimulating hormone and testosterone along with significant increase in serum estradiol level was observed in hyperthyroid rats compared with euthyroid ones. Significant increase in malondialdehyde and nitric oxide concentration associated with significant decrease in superoxide dismutase and catalase activity was also noticed following hyperthyroidism induction. Both reduced glutathione content and glutathione peroxidase activity were increased in hyperthyroid rats compared with control rats. Marked histopathological alterations were observed in testicular section of hyperthyroid rats. These results provide evidence that hypermetabolic state induced by excess level of thyroid hormones may be a causative factor for the impairment of testicular physiology as a consequence of oxidative stress. PMID:25220112

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

    NASA Astrophysics Data System (ADS)

    Aisenberg, Anita; Baruffaldi, Luciana; González, Macarena

    2010-01-01

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

  14. Transitional Urology for Male Adolescents: What Adult Urologists Should Know.

    PubMed

    Suson, Kristina D

    2016-10-01

    In recent years, there has been increasing interest in transitional urology, or how to best prepare patients with major congenital urologic diseases, such as bladder exstrophy and neuropathic bladder, to manage their own health care with adult urologists. However, common pediatric urologic conditions may be encountered by the adult urologist with more regularity. This review focuses on three relatively common conditions which may be identified in childhood, the consequences from which a patient may seek help from an adult urologist: cryptorchidism, varicocele, and Klinefelter syndrome. PMID:27517862

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

    PubMed

    McQuate, Grant T

    2014-01-01

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

  16. Sex dimorphism of the brain in male-to-female transsexuals.

    PubMed

    Savic, Ivanka; Arver, Stefan

    2011-11-01

    Gender dysphoria is suggested to be a consequence of sex atypical cerebral differentiation. We tested this hypothesis in a magnetic resonance study of voxel-based morphometry and structural volumetry in 48 heterosexual men (HeM) and women (HeW) and 24 gynephillic male to female transsexuals (MtF-TR). Specific interest was paid to gray matter (GM) and white matter (WM) fraction, hemispheric asymmetry, and volumes of the hippocampus, thalamus, caudate, and putamen. Like HeM, MtF-TR displayed larger GM volumes than HeW in the cerebellum and lingual gyrus and smaller GM and WM volumes in the precentral gyrus. Both male groups had smaller hippocampal volumes than HeW. As in HeM, but not HeW, the right cerebral hemisphere and thalamus volume was in MtF-TR lager than the left. None of these measures differed between HeM and MtF-TR. MtF-TR displayed also singular features and differed from both control groups by having reduced thalamus and putamen volumes and elevated GM volumes in the right insular and inferior frontal cortex and an area covering the right angular gyrus.The present data do not support the notion that brains of MtF-TR are feminized. The observed changes in MtF-TR bring attention to the networks inferred in processing of body perception. PMID:21467211

  17. Green Light Synergistally Enhances Male Sweetpotato Weevil Response to Sex Pheromone

    PubMed Central

    McQuate, Grant T.

    2014-01-01

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

  18. Peri-pubertal exposure to testicular hormones organizes response to novel environments and social behaviour in adult male rats

    PubMed Central

    Brown, Gillian R.; Kulbarsh, Kyle D.; Spencer, Karen A.; Duval, Camille

    2015-01-01

    Previous research has shown that exposure to testicular hormones during the peri-pubertal period of life has long-term, organizational effects on adult sexual behaviour and underlying neural mechanisms in laboratory rodents. However, the organizational effects of peri-pubertal testicular hormones on other aspects of behaviour and brain function are less well understood. Here, we investigated the effects of manipulating peri-pubertal testicular hormone exposure on later behavioural responses to novel environments and on hormone receptors in various brain regions that are involved in response to novelty. Male rodents generally spend less time in the exposed areas of novel environments than females, and this sex difference emerges during the peri-pubertal period. Male Lister-hooded rats (Rattus norvegicus) were castrated either before puberty or after puberty, then tested in three novel environments (elevated plus-maze, light–dark box, open field) and in an object/social novelty task in adulthood. Androgen receptor (AR), oestrogen receptor (ER1) and corticotropin-releasing factor receptor (CRF-R2) mRNA expression were quantified in the hypothalamus, hippocampus and medial amygdala. The results showed that pre-pubertally castrated males spent more time in the exposed areas of the elevated-plus maze and light–dark box than post-pubertally castrated males, and also confirmed that peri-pubertal hormone exposure influences later response to an opposite-sex conspecific. Hormone receptor gene expression levels did not differ between pre-pubertally and post-pubertally castrated males in any of the brain regions examined. This study therefore demonstrates that testicular hormone exposure during the peri-pubertal period masculinizes later response to novel environments, although the neural mechanisms remain to be fully elucidated. PMID:26159287

  19. Is Audio Computer-Assisted Self-Interview (ACASI) Useful in Risk Behaviour Assessment of Female and Male Sex Workers, Mombasa, Kenya?

    PubMed Central

    van der Elst, Elisabeth M.; Okuku, Haile Selassie; Nakamya, Phellister; Muhaari, Allan; Davies, Alun; McClelland, R. Scott; Price, Matthew A.; Smith, Adrian D.; Graham, Susan M.; Sanders, Eduard J.

    2009-01-01

    Background Audio computer-assisted self-interview (ACASI) may elicit more frequent reporting of socially sensitive behaviours than face-to-face (FtF)-interview. However, no study compared responses to both methods in female and male sex workers (FSW; MSW) in Africa. Methodology/Principal Findings We sequentially enrolled adults recruited for an HIV-1 intervention trial into a comparative study of ACASI and FtF-interview, in a clinic near Mombasa, Kenya. Feasibility and acceptability of ACASI, and a comparative analysis of enrolment responses between ACASI and FtF on an identical risk assessment questionnaire were evaluated. In total, 139 women and 259 men, 81% of eligible cohort participants, completed both interviews. ACASI captured a higher median number of regular (2 vs. 1, p<0.001, both genders) and casual partners in the last week (3 vs. 2, p = 0.04 in women; 2 vs. 1, p<0.001 in men). Group sex (21.6 vs. 13.5%, p<0.001, in men), intravenous drug use (IDU; 10.8 vs. 2.3%, p<0.001 in men; 4.4 vs. 0%, p = 0.03 in women), and rape (8.9 vs. 3.9%, p = 0.002, in men) were reported more frequently in ACASI. A surprisingly high number of women reported in ACASI that they had paid for sex (49.3 vs. 5.8%, p<0.001). Behaviours for recruitment (i.e. anal sex, sex work, sex between males) were reported less frequently in ACASI. The majority of women (79.2%) and men (69.7%) felt that answers given in ACASI were more honest. Volunteers who were not able to take ACASI (84 men, and 37 women) mostly lacked reading skills. Conclusions/Significance About 1 in 5 cohort participants was not able to complete ACASI, mostly for lack of reading skills. Participants who completed ACASI were more likely to report IDU, rape, group sex, and payment for sex by women than when asked in FtF interview. ACASI appears to be a useful tool for high risk behaviour assessments in the African context. PMID:19412535

  20. A Comparison of the Abuse Experiences of Male and Female Adults Molested as Children.

    ERIC Educational Resources Information Center

    Kendall-Tackett, Kathleen A.; Simon, Arthur F.

    To determine whether the molestation experiences of boys and girls differ, this study analyzed data from 365 adults (40 male and 325 female) molested as children, and compared findings for males and females on the identity of the perpetrator, age at onset and end of molestation, duration of molestation, type of sexual acts, and whether the…

  1. Rett Syndrome Symptomatology of Institutionalized Adults with Mental Retardation: Comparison of Males and Females.

    ERIC Educational Resources Information Center

    Burd, Larry; And Others

    1991-01-01

    The study of 297 institutionalized adults with mental retardation found no symptom of Rett syndrome occurred more frequently in males than in females and no single cluster of symptoms appeared to differentiate males from females. Only females were found to meet the necessary criteria for diagnosis of Rett syndrome. (Author/DB)

  2. 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

  3. Reversing song behavior phenotype: testosterone driven induction of singing and measures of song quality in adult male and female canaries (Serinus canaria)

    PubMed Central

    Madison, Farrah N.; Rouse, Melvin L.; Balthazart, Jacques; Ball, Gregory F

    2014-01-01

    In songbirds, such as canaries (Serinus canaria), the song control circuit has been shown to undergo a remarkable change in morphology in response to exogenous testosterone (T). It is also well established that HVC, a telencephalic nucleus involved in song production, is significantly larger in males than in females. T regulates seasonal changes in HVC volume in males and exposure to exogenous T in adult females increases HVC volume and singing activity such that their song becomes more male-like in frequency and structure. However, whether there are sex differences in the ability of T to modulate changes in the song system and song behavior has not been investigated in canaries. In this study, we compared the effects of increasing doses of T on singing and song control nuclei volumes in adult male and female American Singer canaries exposed to identical environmental conditions. Males were castrated and all birds were placed on short days (8L:16D) for 8 weeks. Males and females were implanted either with a 2, 6 or 12 mm long Silastic™ implant filled with crystalline T or an empty 12 mm implant as control. Birds were then housed individually in sound attenuated chambers. Brains were collected from six birds from each group after 1 week or 3 weeks of treatment. Testosterone was not equally effective in increasing singing activity in both males and females. Changes in song quality and occurrence rate took place after a shorter latency in males than in females however, females did undergo marked changes in a number of measures of song behavior if given sufficient time. Males responded with an increase in HVC volume at all three doses. In females, T-induced changes in HVC volume only had limited amplitude and these volumes never reached male-typical levels a suggesting that there are sex differences in the neural substrate that responds to T. PMID:25260250

  4. Correlates of Unprotected Sex Among Adult Heterosexual Men Living with HIV

    PubMed Central

    Richardson, Jean L.; Espinoza, Lilia; Stoyanoff, Sue

    2006-01-01

    The correlates of unprotected sex among a sample of heterosexual men living with HIV (n = 121) were examined to determine whether patient characteristics can be used as a basis for tailoring safer sex counseling in the clinic setting. Potential correlates of self-reported unprotected oral sex (fellatio) and vaginal sex included participant demographics (e.g., age, ethnicity), disease status (CD4 counts, viral load, years since diagnosis), safer sex beliefs (e.g., condom attitudes), substance use, psychological characteristics (depressive symptoms, dispositional optimism and pessimism), and sex partner characteristics (main/casual partner, HIV status of partner, and duration of relationship). A series of logistic regression analyses were used to determine significant relationships. Correlates of reported levels of prior 3-month unprotected fellatio (24%) and vaginal (21%) sex were not associated with the type of relationship (main or casual) or perceived HIV serostatus of the partner (positive, negative, or unknown). Unprotected fellatio was positively associated with age and CD4 count and inversely associated with optimism and positive condom attitudes (all p's < 0.05). Unprotected vaginal sex was positively associated with duration of relationship and inversely associated with positive condom attitudes. Prevention efforts among sexually active adult heterosexual men living with HIV may benefit from focusing on improving attitudes towards condom use regardless of partner relationship status. PMID:16736114

  5. Sex-dependent nutritional programming: fish oil intake during early pregnancy in rats reduces age-dependent insulin resistance in male, but not female, offspring.

    PubMed

    Sardinha, Fatima L C; Fernandes, Flavia S; Tavares do Carmo, Maria G; Herrera, Emilio

    2013-02-15

    Prenatal and early postnatal nutritional status may predispose offspring to impaired glucose tolerance and changes in insulin sensitivity in adult life. The long-term consequences of changes in maternal dietary fatty acid composition were determined in rats. From day 1 until day 12 of pregnancy, rats were given isocaloric diets containing 9% nonvitamin fat based on soybean, olive, fish (FO), linseed, or palm oil. Thereafter, they were maintained on the standard diet; offspring were studied at different ages. Body weight at 4, 8, and 12 mo and lumbar adipose tissue and liver weights at 12 mo did not differ between females on the different diets, whereas in males the corresponding values were all lower in the offspring from the FO group compared with the other dietary groups. Plasma glucose concentrations (both basal and after an oral glucose load) did not change with sex or dietary group, but plasma insulin concentrations were lower in females than in males and, in males, were lowest in the FO group. Similar relations were found with both the homeostasis model assessment of insulin resistance and insulin sensitivity index. In conclusion, the intake of more n-3 fatty acids (FO diet) during early pregnancy reduced both fat accretion and age-related decline in insulin sensitivity in male offspring but not in females. It is proposed that the lower adiposity caused by the increased n-3 fatty acids during the intrauterine life was responsible of the lower insulin resistance in male offspring. PMID:23255588

  6. Sex Differences in the Timing of Identification among Children and Adults with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Begeer, Sander; Mandell, David; Wijnker-Holmes, Bernadette; Venderbosch, Stance; Rem, Dorien; Stekelenburg, Fred; Koot, Hans M.

    2013-01-01

    To examine differences by sex in the timing of identification of individuals with autism spectrum disorders (ASD), survey data were collected in the Netherlands from 2,275 males and females with autistic disorder, Asperger's syndrome and PDD-NOS. Among participants less than 18 years of age, females with Asperger's syndrome were identified later…

  7. Peer norms and consistent condom use with female sex workers among male clients in Sichuan province, China.

    PubMed

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

    2010-08-01

    Despite their crucial role in HIV infection and transmission, commercial sex male clients (CSMCs) are rarely studied. The purpose of this study was to examine the relationship between peer norms and consistent condom use with female sex workers (FSWs) among CSMCs in Sichuan province, China. Male clients with peers who had paid for sex (n = 562) were recruited by local health workers through snowball sampling. Measures of peer norms included 1) descriptive norms which were evaluated by perceptions of peer's condom attitudes and behaviors with FSWs; 2) injunctive norms which were assessed by the perceived peer approval of using condoms with FSWs; and 3) communication of HIV-related topics with peers. The outcome was consistent condom use with FSWs. Results of multivariate logistic regression models revealed that consistent condom use with FSWs was significantly more likely among male clients who perceived more pro-condom descriptive and injunctive norms among their peer groups. In addition, the pattern of commercial sex visits moderated the relations between peer norms and consistent condom use with FSWs. More peer approval of condom use and more HIV-related communication were significantly associated with consistent condom use among clients who visited FSWs with friends but not among those who visited FSWs alone. The findings suggest that social activities surrounding commercial sex visits may provide an entry point for HIV prevention intervention with men who patronize FSWs and that such efforts should tap into existing dynamics of social interaction to promote pro-condom norms. PMID:20541859

  8. The effects of prepubertal gonadectomy and binge-like ethanol exposure during adolescence on ethanol drinking in adult male and female rats

    PubMed Central

    Sherrill, Luke K.; Koss, Wendy A.; Foreman, Emily S.; Gulley, Joshua M.

    2010-01-01

    The pubertal surge in gonadal hormones that occurs during adolescence may impact the long-term effects of early alcohol exposure and sex differences in drinking behavior in adulthood. We investigated this hypothesis by performing sham or gonadectomy surgeries in Long Evans rats around postnatal day (P) 20. From P35–45, males and females were given saline or 3.0 g/kg ethanol using a binge-like model of exposure (8 injections total). As adults (P100), they were trained to self-administer ethanol via a sucrose-fading procedure and then given access to different unsweetened concentrations (5–20% w/v) for 5 days/concentration. We found that during adolescence, ethanol-induced intoxication was similar in males and females that underwent sham surgery. In gonadectomized males and females, however, the level of intoxication was greater following the last injection compared to the first. During adulthood, females drank more sucrose per body weight than males and binge-like exposure to ethanol reduced sucrose consumption in both sexes. These effects were not seen in gonadectomized rats. Ethanol consumption was higher in saline-exposed females compared to males, with gonadectomy reversing this sex difference by increasing consumption in males and decreasing it in females. Exposure to ethanol during adolescence augmented ethanol consumption in both sexes, but this effect was statistically significant only in gonadectomized females. Together, these results support a role for gonadal hormones during puberty in the short- and long-term effects of ethanol on behavior and in the development of sex differences in consummatory behavior during adulthood. PMID:20816899

  9. The effects of pre-pubertal gonadectomy and binge-like ethanol exposure during adolescence on ethanol drinking in adult male and female rats.

    PubMed

    Sherrill, Luke K; Koss, Wendy A; Foreman, Emily S; Gulley, Joshua M

    2011-01-20

    The pubertal surge in gonadal hormones that occurs during adolescence may impact the long-term effects of early alcohol exposure and sex differences in drinking behavior in adulthood. We investigated this hypothesis by performing sham or gonadectomy surgeries in Long-Evans rats around post-natal day (P) 20. From P35-45, males and females were given saline or 3.0 g/kg ethanol using a binge-like model of exposure (8 injections total). As adults (P100), they were trained to self-administer ethanol via a sucrose-fading procedure and then given access to different unsweetened concentrations (5-20%, w/v) for 5 days/concentration. We found that during adolescence, ethanol-induced intoxication was similar in males and females that underwent sham surgery. In gonadectomized males and females, however, the level of intoxication was greater following the last injection compared to the first. During adulthood, females drank more sucrose per body weight than males and binge-like exposure to ethanol reduced sucrose consumption in both sexes. These effects were not seen in gonadectomized rats. Ethanol consumption was higher in saline-exposed females compared to males, with gonadectomy reversing this sex difference by increasing consumption in males and decreasing it in females. Exposure to ethanol during adolescence augmented ethanol consumption in both sexes, but this effect was statistically significant only in gonadectomized females. Together, these results support a role for gonadal hormones during puberty in the short- and long-term effects of ethanol on behavior and in the development of sex differences in consummatory behavior during adulthood. PMID:20816899

  10. Sexing Adult Pale-Winged Starlings Using Morphometric and Discriminant Function Analysis

    PubMed Central

    Henry, Laurence; Biquand, Véronique; Craig, Adrian J. F. K.; Hausberger, Martine

    2015-01-01

    Accurate sexing of birds is vital for behavioral studies but can be a real problem in the field, especially for monomorphic species. Our goal here was to characterize the morphology of male and female monomorphic pale-winged starlings (Onychognathus nabouroup), a South African sturnid whose plumage is sexually monomorphic. Morphological measurements of genetically sexed animals indicated that males were statistically larger than females for five measurements: Mass, tail length, tarsus length and wing length. By using a Discriminant Function Analysis based on the measurements taken by one ringer, we were able to predict correctly the sex of 81.10% of the birds of data collected in the field and 77.9% of museum skins independently of year of capture and ringer. The model developed here should be useful for further field studies of this species. PMID:26367269

  11. Sexing Adult Pale-Winged Starlings Using Morphometric and Discriminant Function Analysis.

    PubMed

    Henry, Laurence; Biquand, Véronique; Craig, Adrian J F K; Hausberger, Martine

    2015-01-01

    Accurate sexing of birds is vital for behavioral studies but can be a real problem in the field, especially for monomorphic species. Our goal here was to characterize the morphology of male and female monomorphic pale-winged starlings (Onychognathus nabouroup), a South African sturnid whose plumage is sexually monomorphic. Morphological measurements of genetically sexed animals indicated that males were statistically larger than females for five measurements: Mass, tail length, tarsus length and wing length. By using a Discriminant Function Analysis based on the measurements taken by one ringer, we were able to predict correctly the sex of 81.10% of the birds of data collected in the field and 77.9% of museum skins independently of year of capture and ringer. The model developed here should be useful for further field studies of this species. PMID:26367269

  12. Sex Ratio and Body Mass of Adult Herbivorous Beetles Depend on Time of Occurrence and Light Conditions

    PubMed Central

    Łukowski, Adrian; Mąderek, Ewa; Giertych, Marian J.; Karolewski, Piotr

    2015-01-01

    Body mass and sex ratio (F/M) of folivorous insects are easily measured parameters that are commonly used to assess the effect of food quality, living conditions, and preferences on the selection of favourable sites for offspring. A study was conducted on the polyphagous beetle, Gonioctena quinquepunctata (a pest of the native Prunus padus and alien P. serotina) and on the monophagous beetle, Altica brevicollis coryletorum (a pest of Corylus avellana). Both species have a similar life cycle with emergence of current-year adults in summer, and reproduction of 1-year-old insects in spring. A. brevicollis coryletorum feeds primarily on sunlit shrubs, while G. quinquepunctata prefers shaded leaves. The present study assessed the effect of time of occurrence (insect age) on body mass in both sexes and on the sex ratio F/M, taking into account the influence of light conditions associated with their favoured food source (sunlit vs. shaded leaves). We hypothesized that a change in body mass in current-year insects would be determined by the amount of consumed food, while the sex ratio would be stable, when in 1-year-old insects females would die shortly after oviposition, while males would be active for a prolonged time. Results confirmed the hypothesis that changes in mass of current-year beetles was determined by the amount of food intake. We also found that in spring, unfertilized females coexist with fertilized ones and that the latter females live for some time after oviposition; resulting in fluctuations of the mean mass for females. In both species, 1-year-old beetles were heavier than current-year. The preference of A. brevicollis coryletorum for sunlit leaves results in a higher body weight than in G. quinquepunctata in both seasons. The data are consistent and indicate seasonal fluctuations in body mass and changes in the sex ratio in 1-year-old beetles, due to the entrance into their reproductive period. PMID:26657564

  13. Sex Ratio and Body Mass of Adult Herbivorous Beetles Depend on Time of Occurrence and Light Conditions.

    PubMed

    Łukowski, Adrian; Mąderek, Ewa; Giertych, Marian J; Karolewski, Piotr

    2015-01-01

    Body mass and sex ratio (F/M) of folivorous insects are easily measured parameters that are commonly used to assess the effect of food quality, living conditions, and preferences on the selection of favourable sites for offspring. A study was conducted on the polyphagous beetle, Gonioctenaquinquepunctata (a pest of the native Prunus padus and alien P. serotina) and on the monophagous beetle, Alticabrevicollis coryletorum (a pest of Corylus avellana). Both species have a similar life cycle with emergence of current-year adults in summer, and reproduction of 1-year-old insects in spring. A. brevicollis coryletorum feeds primarily on sunlit shrubs, while G. quinquepunctata prefers shaded leaves. The present study assessed the effect of time of occurrence(insect age) on body mass in both sexes and on the sex ratio F/M, taking into account the influence of light conditions associated with their favoured food source (sunlit vs. shaded leaves). We hypothesized that a change in body mass in current-year insects would be determined by the amount of consumed food, while the sex ratio would be stable, when in 1-year-old insects females would die shortly after oviposition, while males would be active for a prolonged time. Results confirmed the hypothesis that changes in mass of current-year beetles was determined by the amount of food intake. We also found that in spring, unfertilized females coexist with fertilized ones and that the latter females live for some time after oviposition; resulting in fluctuations of the mean mass for females. In both species, 1-year-old beetles were heavier than current-year. The preference of A. brevicollis coryletorum for sunlit leaves results in a higher body weight than in G. quinquepunctata in both seasons. The data are consistent and indicate seasonal fluctuations in body mass and changes in the sex ratio in 1-year-old beetles, due to the entrance into their reproductive period. PMID:26657564

  14. 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…

  15. EAG and behavioral responses of Helicoverpa armigera males to volatiles from poplar leaves and their combinations with sex pheromone.

    PubMed

    Deng, Jian-Yu; Huang, Yong-Ping; Wei, Hong-Yi; Du, Jia-Wei

    2004-12-01

    Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Helicoverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate, linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These results suggested that some volatiles should modify sex pheromone caused behavior and that some of them could possibly be used as a tool for disrupting mating or for enhancing the effect of synthetic sex pheromone in the field. PMID:15547967

  16. 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…

  17. 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…

  18. Disparities in Health and Disability Among Older Adults in Same-Sex Cohabiting Relationships

    PubMed Central

    Gonzales, Gilbert; Henning-Smith, Carrie

    2014-01-01

    Objectives The present study compared indicators of impaired health and disability between older adults in same-sex cohabiting relationships and their peers in opposite-sex cohabiting relationships. Methods Data were obtained on men (n=698) and women (n=630) aged 50 years and older and in self-reported same-sex relationships from the National Health Interview Survey. Multiple regression analyses were conducted to estimate differences in physical health, mental health and disability status. Results Compared to their peers in married opposite-sex relationships, older men in same-sex relationships exhibited greater odds of psychological distress, and older women in same-sex relationships experienced elevated odds of poor/fair health, needing help with ADLs and IADLs, functional limitations, and psychological distress. Discussion This study adds to the limited information on health and disability among older lesbian, gay and bisexual adults. As this population grows, gerontologists must develop a better understanding of the unique issues and challenges facing them and their families. PMID:25253727

  19. Frequency and inheritance of non-male producing clones in Daphnia magna: evolution towards sex specialization in a cyclical parthenogen?

    PubMed

    Galimov, Y; Walser, B; Haag, C R

    2011-07-01

    In Daphnia (Cladocera, Crustacea), parthenogenetic reproduction alternates with sexual reproduction. Individuals of both sexes that belong to the same parthenogenetic line are genetically identical, and their sex is determined by the environment. Previously, non-male producing (NMP) genotypes have been described in species of the Daphnia pulex group. Such genotypes can only persist through phases of sexual reproduction if they co-occur with normal (MP) genotypes that produce both males and females, and thus the breeding system polymorphism is similar to gynodioecy (coexistence of females with hermaphrodites), which is well known in plants. Here we show that the same breeding system polymorphism also occurs in Daphnia magna, a species that has diverged from D. pulex more than 100 MY ago. Depending on the population, between 0% and 40% of D. magna females do not produce males when experimentally exposed to a concentration of the putative sex hormone methyl farnesoate that normally leads to male-only clutches. Natural broods of these NMP females never contained males, contrasting with high proportions of male offspring in MP females from the same populations. The results from a series of crossing experiments suggest that NMP is determined by a dominant allele at a single nuclear locus (or a several closely linked loci): NMP × MP crosses always yielded 50% NMP and 50% MP offspring, whereas MP × MP crosses always yielded 100% MP offspring. Based on cytochrome c oxidase subunit I-sequences, we found that NMP genotypes from different populations belong to three highly divergent mitochondrial lineages, potentially representing three independent evolutionary origins of NMP in D. magna. Thus, the evolution of NMP genotypes in cyclical parthenogens may be more common than previously thought. Moreover, MP genotypes that coexist with NMP genotypes may have responded to the presence of the latter by partially specializing on male production. Hence, these populations of D

  20. 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

  1. Interacting Factors Associated with Adult Male Drowning in New Zealand

    PubMed Central

    Croft, James L.; Button, Chris

    2015-01-01

    Objectives i) to identify factors that contribute to the global trend of the higher incidence of male drowning relative to females, and; ii) to explore relationships between such factors from mortality data in New Zealand. Methods Drownings from 1983 to 2012 were examined for: Age, Ethnicity, Site, Activity, Buoyancy and Alcohol. Conditional frequency tables presented as mosaic plots were used to assess the interactions of these factors. Results Alcohol was involved in a high proportion of Accidental Immersion drownings (61%) and was highest for males aged 20-24 years. When alcohol was involved there were proportionally more incidences where a life jacket was Available But Not Worn and less incidences where a life jacket was Worn. Many 30-39 year old males drowned during underwater activities (e.g., snorkeling, diving). Older men (aged +55 years old) had a high incidence of drowning while boating. Different ethnicities were over-represented in different age groups (Asian men aged 25-29, and European men aged 65-74) and when involved in different activities. Conclusions Numerous interacting factors are responsible for male drownings. In New Zealand, drowning locations and activities differ by age and ethnicity which require targeted intervention strategies. PMID:26083689

  2. The Individual with Intellectual Disabilities and Sex Education: Perspectives of Involved Adults.

    ERIC Educational Resources Information Center

    Brown, Randel D.

    This study examined the perceptions of involved adults concerning sex education for individuals with intellectual disabilities. Participants were 40 individuals who provided direct care or instruction to individuals with intellectual disabilities or who had administrative responsibility for them. They completed a 36-item Q-sort that examined their…

  3. Race-Sex Differences in Job Quality Returns Attributed to Education among Young Rural Adults.

    ERIC Educational Resources Information Center

    Eggers, Judi L.; Dunkelberger, John E.

    Using the general hypothesis that job quality returns to education are positive for all employment indicators among race and sex groupings, a sample of young adults originally from southern rural areas and small towns was queried concerning the status ranking of their current occupation, income earned, supervisory responsibility, and extent of…

  4. Sex Role Strain Among Kibbutz Adolescents and Adults: A Developmental Perspective.

    ERIC Educational Resources Information Center

    Snarey, John; And Others

    1986-01-01

    It was hypothesized that adolescent females experience greater sex role strain than other kibbutz members. Loevinger's ego development test was administered to 40 kibbutz members. The findings supported the hypothesis and showed that adult women are significantly more likely to focus their dissatisfaction in the area of actual role behavior. (JAZ)

  5. Adult Development and Life Satisfaction Functions of Sex, Marital Status and Age.

    ERIC Educational Resources Information Center

    Coles, Claire; McCall, Fran

    Quality of life in adulthood (ages 27-47) was investigated; age, marital status and sex were considered the primary variables. Attention was given to the consideration of the current crises-oriented theory of adult development. The interrelationship of the variables was of principle interest in assessing life satisfaction and personality…

  6. Untreated ADHD in Adults: Are There Sex Differences in Symptoms, Comorbidity, and Impairment?

    ERIC Educational Resources Information Center

    Rasmussen, Kirsten; Levander, Sten

    2009-01-01

    Objective: To analyze sex differences among adult, never-treated patients referred for central stimulant treatment of ADHD. Method: Data for 600 consecutive patients from northern Norway referred for evaluation by an expert team during 7 years were analyzed. General background information, diagnostic and social history, and symptom profiles were…

  7. Peri-conceptional obesogenic exposure induces sex-specific programming of disease susceptibilities in adult mouse offspring.

    PubMed

    Dahlhoff, M; Pfister, S; Blutke, A; Rozman, J; Klingenspor, M; Deutsch, M J; Rathkolb, B; Fink, B; Gimpfl, M; Hrabě de Angelis, M; Roscher, A A; Wolf, E; Ensenauer, R

    2014-02-01

    Vulnerability of the fetus upon maternal obesity can potentially occur during all developmental phases. We aimed at elaborating longer-term health outcomes of fetal overnutrition during the earliest stages of development. We utilized Naval Medical Research Institute (NMRI) mice to induce pre-conceptional and gestational obesity and followed offspring outcomes in the absence of any postnatal obesogenic influences. Male adult offspring developed overweight, insulin resistance, hyperleptinemia, hyperuricemia and hepatic steatosis; all these features were not observed in females. Instead, they showed impaired fasting glucose and a reduced fat mass and adipocyte size. Influences of the interaction of maternal diet∗sex concerned offspring genes involved in fatty liver disease, lipid droplet size regulation and fat mass expansion. These data suggest that a peri-conceptional obesogenic exposure is sufficient to shape offspring gene expression patterns and health outcomes in a sex- and organ-specific manner, indicating varying developmental vulnerabilities between sexes towards metabolic disease in response to maternal overnutrition. PMID:24275555

  8. Risk of Intimate Partner Violence among Young Adult Males with Childhood ADHD

    PubMed Central

    Wymbs, Brian T.; Molina, Brooke S. G.; Pelham, William E.; Cheong, JeeWon; Gnagy, Elizabeth M.; Belendiuk, Katherine A.; Walther, Christine A. P.; Babinski, Dara E.; Waschbusch, Daniel A.

    2010-01-01

    Objective Research has clearly documented the social dysfunction of youth with attention-deficit hyperactivity disorder (ADHD). However, little is known about the interpersonal relationships of adults diagnosed with ADHD in childhood, including rates of intimate partner violence (IPV). Method Using data from the Pittsburgh ADHD Longitudinal Study, analyses compared the level of IPV (verbal aggression, violence) reported by young adult (18-25 year-old) males with childhood ADHD (n=125) to reports by demographically-similar males without ADHD histories (n=88). Results Males with childhood ADHD, especially those with conduct problems persisting from childhood, were more likely to be verbally aggressive and violent with romantic partners than males without histories of ADHD or conduct problems. Conclusion Research is needed to replicate these findings, to explore potential mechanisms, and to develop effective interventions for romantic relationship discord among young adults with ADHD histories, especially those with persistent conduct problems. PMID:22044962

  9. Opioid Receptor-Dependent Sex Differences in Synaptic Plasticity in the Hippocampal Mossy Fiber Pathway of the Adult Rat

    PubMed Central

    Harte-Hargrove, Lauren C.; Varga-Wesson, Ada; Duffy, Aine M.; Milner, Teresa A.

    2015-01-01

    The mossy fiber (MF) pathway is critical to hippocampal function and influenced by gonadal hormones. Physiological data are limited, so we asked whether basal transmission and long-term potentiation (LTP) differed in slices of adult male and female rats. The results showed small sex differences in basal transmission but striking sex differences in opioid receptor sensitivity and LTP. When slices were made from females on proestrous morning, when serum levels of 17β-estradiol peak, the nonspecific opioid receptor antagonist naloxone (1 μm) enhanced MF transmission but there was no effect in males, suggesting preferential opioid receptor-dependent inhibition in females when 17β-estradiol levels are elevated. The μ-opioid receptor (MOR) antagonist Cys2,Tyr3,Orn5,Pen7-amide (CTOP; 300 nm) had a similar effect but the δ-opioid receptor (DOR) antagonist naltrindole (NTI; 1 μm) did not, implicating MORs in female MF transmission. The GABAB receptor antagonist saclofen (200 μm) occluded effects of CTOP but the GABAA receptor antagonist bicuculline (10 μm) did not. For LTP, a low-frequency (LF) protocol was used because higher frequencies elicited hyperexcitability in females. Proestrous females exhibited LF-LTP but males did not, suggesting a lower threshold for synaptic plasticity when 17β-estradiol is elevated. NTI blocked LF-LTP in proestrous females, but CTOP did not. Electron microscopy revealed more DOR-labeled spines of pyramidal cells in proestrous females than males. Therefore, we suggest that increased postsynaptic DORs mediate LF-LTP in proestrous females. The results show strong MOR regulation of MF transmission only in females and identify a novel DOR-dependent form of MF LTP specific to proestrus. PMID:25632146

  10. Comprehensive Transcriptome Analysis of Sex-Biased Expressed Genes Reveals Discrete Biological and Physiological Features of Male and Female Schistosoma japonicum

    PubMed Central

    Piao, Xianyu; Hou, Nan; Gobert, Geoffrey N.; McManus, Donald P.; Chen, Qijun

    2016-01-01

    Schistosomiasis is a chronic and debilitating disease caused by blood flukes (digenetic trematodes) of the genus Schistosoma. Schistosomes are sexually dimorphic and exhibit dramatic morphological changes during a complex lifecycle which requires subtle gene regulatory mechanisms to fulfil these complex biological processes. In the current study, a 41,982 features custom DNA microarray, which represents the most comprehensive probe coverage for any schistosome transcriptome study, was designed based on public domain and local databases to explore differential gene expression in S. japonicum. We found that approximately 1/10 of the total annotated genes in the S. japonicum genome are differentially expressed between adult males and females. In general, genes associated with the cytoskeleton, and motor and neuronal activities were readily expressed in male adult worms, whereas genes involved in amino acid metabolism, nucleotide biosynthesis, gluconeogenesis, glycosylation, cell cycle processes, DNA synthesis and genome fidelity and stability were enriched in females. Further, miRNAs target sites within these gene sets were predicted, which provides a scenario whereby the miRNAs potentially regulate these sex-biased expressed genes. The study significantly expands the expressional and regulatory characteristics of gender-biased expressed genes in schistosomes with high accuracy. The data provide a better appreciation of the biological and physiological features of male and female schistosome parasites, which may lead to novel vaccine targets and the development of new therapeutic interventions. PMID:27128440

  11. Comprehensive Transcriptome Analysis of Sex-Biased Expressed Genes Reveals Discrete Biological and Physiological Features of Male and Female Schistosoma japonicum.

    PubMed

    Cai, Pengfei; Liu, Shuai; Piao, Xianyu; Hou, Nan; Gobert, Geoffrey N; McManus, Donald P; Chen, Qijun

    2016-04-01

    Schistosomiasis is a chronic and debilitating disease caused by blood flukes (digenetic trematodes) of the genus Schistosoma. Schistosomes are sexually dimorphic and exhibit dramatic morphological changes during a complex lifecycle which requires subtle gene regulatory mechanisms to fulfil these complex biological processes. In the current study, a 41,982 features custom DNA microarray, which represents the most comprehensive probe coverage for any schistosome transcriptome study, was designed based on public domain and local databases to explore differential gene expression in S. japonicum. We found that approximately 1/10 of the total annotated genes in the S. japonicum genome are differentially expressed between adult males and females. In general, genes associated with the cytoskeleton, and motor and neuronal activities were readily expressed in male adult worms, whereas genes involved in amino acid metabolism, nucleotide biosynthesis, gluconeogenesis, glycosylation, cell cycle processes, DNA synthesis and genome fidelity and stability were enriched in females. Further, miRNAs target sites within these gene sets were predicted, which provides a scenario whereby the miRNAs potentially regulate these sex-biased expressed genes. The study significantly expands the expressional and regulatory characteristics of gender-biased expressed genes in schistosomes with high accuracy. The data provide a better appreciation of the biological and physiological features of male and female schistosome parasites, which may lead to novel vaccine targets and the development of new therapeutic interventions. PMID:27128440

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

    2015-01-01

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

  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. [Importance of adult protein ingestion on the mating success of Ceratitis capitata Wiedemann males (Diptera: Tephritidae)].

    PubMed

    Silva Neto, Alberto M da; Dias, Vanessa S; Joachim-Bravo, Iara S

    2010-01-01

    The importance of the protein ingestion during the adult stage on the mating success of males of Ceratitis capitata Wiedemann was evaluated in experiments of laboratory and field cage. In laboratory, the effects of protein ingestion during the first four or 12 days of the male adult life was assessed by the following parameters: mating success (capacity of being chosen by the female) and the number of males that give out pheromonal signals. Some experiments of mating success had been carried through with males in different ratios. In these tests, the number of males which had ingested protein (an unique male) was remained constant and the number of males fed without protein was gradually increased from 1:1 to 1:5. In the field cages, the mating success experiments were done using a 1:1 ratio. The results showed that the protein ingestion in the first four days of life did not influence any of the analyzed parameters. When the period of ingestion of protein was extended to 12 days, protein-fed males fed produced more pheromonal signals and had a higher mating success when at a 1:1 ratio in laboratory and field cage assays. In laboratory, females randomly chose males in any other tested ratio (1:2, 1:3, 1:4 and 1:5), indicating that the female may lose the perception to identify the male who ingested protein in the first 12 days. PMID:20498961

  15. 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.

  16. Kin recognition and cannibalistic behaviours by adult male fathead minnows ( Pimephales promelas)

    NASA Astrophysics Data System (ADS)

    Green, Warren W.; Mirza, Reehan S.; Pyle, Greg G.

    2008-03-01

    Parental care is an energetically demanding activity that ensures genes are efficiently passed from one generation to the next. According to evolutionary theory, the greatest energetic investment should be directed towards offspring that are most closely related to the parent. Male fathead minnows, Pimephales promelas, provide this parental investment to developing embryos but not newly hatched larvae. Therefore, selection should favour recognition of embryonic kin to ensure energetic expenditure is optimally invested. In this study, adult male fathead minnows were tested using behavioural assays, with egg cannibalism as an endpoint, to determine whether adult males could discriminate between related and unrelated embryos. Egg cannibalism was highest when adult male fathead minnows were presented with unrelated eggs and lowest when presented with eggs fertilized by the test subject (related eggs). The degree of cannibalism was also a function of breeding status. Unrelated males in breeding condition showed an intermediate response between the low cannibalism demonstrated by related males and the high cannibalism demonstrated by unrelated males in a nonbreeding condition. These results suggest that although male fathead minnows can discriminate between unrelated and related embryos, at least some component of parental investment is a simple function of breeding status.

  17. Haploinsufficiency of SF-1 Causes Female to Male Sex Reversal in Nile Tilapia, Oreochromis niloticus.

    PubMed

    Xie, Qing-Ping; He, Xue; Sui, Yi-Ning; Chen, Li-Li; Sun, Li-Na; Wang, De-Shou

    2016-06-01

    Steroidogenic factor-1 (Sf-1) (officially designated nuclear receptor subfamily 5 group A member 1 [NR5A1]) is a master regulator of steroidogenesis and reproduction in mammals. However, its function remains unclear in nonmammalian vertebrates. In the present study, we used immunohistochemistry to detect expression of Sf-1 in the steroidogenic cells, the interstitial, granulosa, and theca cells of the ovary, and the Leydig cells of the testis, in Nile tilapia. Clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (Cas9) cleavage of sf-1 resulted in a high mutation rate in the F0 generation and a phenotype of gonadal dysgenesis and reduced steroidogenic cells in XX and XY fish. Sf-1 deficiency also resulted in decreased cytochrome P450, family 19, subfamily A, polypeptide 1a, forkhead box L2 expression, and serum estradiol-17β in XX fish. In XY fish, Sf-1 deficiency increased cytochrome P450, family 19, subfamily A, polypeptide 1a and forkhead box L2 expression but decreased cytochrome P450, family 11, subfamily B, polypeptide 2 expression and serum 11-ketotestosterone levels. 17α-methyltestosterone treatment successfully rescued the gonadal phenotype of Sf-1-deficient XY fish, as demonstrated by normal spermatogenesis and production of F1 mutants. In contrast, estradiol-17β treatment only partially rescued the gonadal phenotype of Sf-1-deficient XX fish, as demonstrated by the appearance of phase II oocytes. Furthermore, both sf-1(+/-) F1 XX and XY mutants developed as fertile males, although spermatogenesis was delayed and efferent duct formation was disordered. Our data suggest that Sf-1 is a major regulator of steroidogenesis and reproduction in fish, as it is in mammals. Sf-1 deficiency resulted in gonadal dysgenesis and feminization of XY gonads. However, unlike in mammals, Sf-1 deficiency also resulted in female to male sex reversal in 8.1% of F0 and 92.1% of sf-1(+/-) F1 in XX fish. PMID:27046435

  18. Effect of dietary protein levels on sex hormones in growing male rats kept under constant darkness.

    PubMed

    Hanai, Miho; Esashi, Takatoshi

    2012-01-01

    The purpose of this experiment was to clarify the effects of dietary protein levels on the gonadal development and sex hormones in male rats kept under constant darkness as a model of disturbed daily rhythm. Four-week-old male rats (Fischer 344 strain) were kept under constant darkness or normal lighting (12-h light/dark cycle). Two kinds of experimental diet were prepared, one with low dietary protein levels (9% casein) and one with normal levels (18% casein). Harper mineral mixture and Panvitan were used as mineral and vitamin sources, respectively. After 4 weeks, gonadal weight, serum testosterone, and other hormone contents were evaluated. The gonadal weight in the constant darkness groups (D-groups) was lower than that in the normal lighting groups (N-groups). Although the low-protein diet in the D-groups significantly reduced gonadal weight, the normal-protein diet mitigated the reduction of gonadal weight in rats kept under constant darkness. Serum testosterone and androstenedione concentrations were lower in D-group rats fed the low-protein diet. There were no effects of lighting condition or protein levels on serum luteinizing hormone (LH), follicle- stimulating hormone (FSH), or progesterone concentrations. These results indicate that the suppression of gonadal development in D-group rats fed the low-protein diet was caused by low testosterone, which we attribute to the inhibition of synthesized androstenedione, a precursor of testosterone. The present study showed that constant darkness and the low- protein diet inhibited the synthetic pathway from progesterone to androstenedione. PMID:23095819

  19. The Impact of Sex of Psychological Examiner on Sexually Abused Girls' Preference for and Anticipated Comfort with Male versus Female Counselors.

    ERIC Educational Resources Information Center

    Fowler, William E.; And Others

    1992-01-01

    As part of a psychological evaluation, 35 sexually abused girls were asked to indicate their preference for a male or female counselor. Girls evaluated by male examiners were less likely to have a clear preference for a female counselor. The sex of the examiner was related to participants' anticipated comfort with a counselor of a particular sex.…

  20. Adolescent Sex Offenders' Rankings of Therapeutic Factors Using the Yalom Card Sort

    ERIC Educational Resources Information Center

    Sribney, Christine L.; Reddon, John R.

    2008-01-01

    Following 11-98 weeks of inpatient residential treatment, 69 male adolescent sex offenders completed the 60-item, 12-factor Yalom Card Sort. The rank orders were compared to adult sex offenders and a psychiatric adult outpatient group. Relative to adult psychiatric outpatients, the adolescent sex offenders had rated Instillation of Hope three…

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

    PubMed

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

    2001-10-01

    This paper describes the sociodemographic and work characteristics, prevalence of HIV infection and associated risk behaviours among male sex workers (MSWs) in Madrid (Spain). Using an anonymous semi-structured questionnaire, educators attached to a mobile unit under a street-based prostitution programme surveyed 84 MSWs from several Madrid areas. Of the total surveyed: 35% were immigrants, mean age was 23 years, mean period in prostitution was four years; 21% had no primary education; 16% had injected drugs at some time; 11% reported private sexual relationships exclusively with women; 89% always used condoms in anal practices with clients; and 41% were in sexual relationships with their partners. Only 11% had ever used fortified condoms. In the preceding month, 37% had experienced condom failure, 82% without having used any lubricant. In all, 67% reported having undergone HIV testing, with a higher percentage of positive results among injecting (60%) versus non-injecting drug users (17%). Immigrants had a lower level of education, made less use of condoms, had more condom failures and, in their private lives, a greater proportion reported sexual relationships exclusively with women. In Spain, MSWs should be included in HIV prevention programmes, which ought to be specifically adapted to immigrants. Priority should be given to reducing the condom failure rate in anal intercourse, by improving access to fortified condoms. PMID:11571014

  2. The association between church attendance and psychological health in Northern Ireland: a national representative survey among adults allowing for sex differences and denominational difference.

    PubMed

    Lewis, Christopher Alan; Shevlin, Mark; Francis, Leslie J; Quigley, Catherine F

    2011-12-01

    This study extends previous research concerning the association between religion and psychological health in six ways: (1) by focusing clearly on religious attendance (church attendance); (2) by employing a robust measure of psychological distress (GHQ-12); (3) by studying a highly religious culture (Northern Ireland); (4) by taking sex differences into account (male or female); (5) by taking denominational differences into account (Catholic or Protestant); (6) and by obtaining a national representative sample (N = 4,281 adults aged 16 and above). Results from a 2 (sex) by 2 (denomination) ANCOVA demonstrated that Catholics recorded significantly lower levels of psychological health compared to Protestants, and that females showed significantly lower levels of psychological health compared to males. In addition, females reported higher frequency of religious service attendance than males, and Catholics reported higher attendance rates than Protestants. A significant positive association was found between frequency of religious attendance and GHQ-12 scores, and this association was moderated by sex and denomination. In conclusion, the results suggest that there may be sex and denominational differences in further understanding the relationship between frequency of religious attendance and psychological health. PMID:20108121

  3. Stress and serial adult metamorphosis: multiple roles for the stress axis in socially regulated sex change

    PubMed Central

    Solomon-Lane, Tessa K.; Crespi, Erica J.; Grober, Matthew S.

    2013-01-01

    Socially regulated sex change in teleost fishes is a striking example of social status information regulating biological function in the service of reproductive success. The establishment of social dominance in sex changing species is translated into a cascade of changes in behavior, physiology, neuroendocrine function, and morphology that transforms a female into a male, or vice versa. The hypothalamic-pituitary-interrenal axis (HPI, homologous to HP-adrenal axis in mammals and birds) has been hypothesized to play a mechanistic role linking status to sex change. The HPA/I axis responds to environmental stressors by integrating relevant external and internal cues and coordinating biological responses including changes in behavior, energetics, physiology, and morphology (i.e., metamorphosis). Through actions of both corticotropin-releasing factor and glucocorticoids, the HPA/I axis has been implicated in processes central to sex change, including the regulation of agonistic behavior, social status, energetic investment, and life history transitions. In this paper, we review the hypothesized roles of the HPA/I axis in the regulation of sex change and how those hypotheses have been tested to date. We include original data on sex change in the bluebanded goby (Lythyrpnus dalli), a highly social fish capable of bidirectional sex change. We then propose a model for HPA/I involvement in sex change and discuss how these ideas might be tested in the future. Understanding the regulation of sex change has the potential to elucidate evolutionarily conserved mechanisms responsible for translating pertinent information about the environment into coordinated biological changes along multiple body axes. PMID:24265604

  4. Sex-Role Development and Parental Expectations among Disturbed Adolescent Males

    ERIC Educational Resources Information Center

    Small, Arnold; And Others

    1975-01-01

    This study was designed to examine the sex-linked personality traits of adolescents referred to out-patient clinics for a variety of psychological problems, the sex-linked personality traits of their parents, and the sex-linked personality characteristics that the parents of these adolescents would ideally like for their sons. (Author/RK)

  5. 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...

  6. Estradiol differentially affects auditory recognition and learning according to photoperiodic state in the adult male songbird, European starling (Sturnus vulgaris)

    PubMed Central

    Knudsen, Daniel P.; Krause, Jesse S.; Wingfield, John C.; Gentner, Timothy Q.

    2013-01-01

    Changes in hormones can affect many types of learning in vertebrates. Adults experience fluctuations in a multitude of hormones over a temporal scale, from local, rapid action to more long-term, seasonal changes. Endocrine changes during development can affect behavioral outcomes in adulthood, but how learning is affected in adults by hormone fluctuations experienced during adulthood is less understood. Previous reports have implicated the sex steroid hormone estradiol (E2) in both male and female vertebrate cognitive functioning. Here, we examined the effects of E2 on auditory recognition and learning in male European starlings (Sturnus vulgaris). European starlings are photoperiodic, seasonally breeding songbirds that undergo different periods of reproductive activity according to annual changes in day length. We simulated these reproductive periods, specifically 1. photosensitivity, 2. photostimulation, and 3. photorefractoriness in captive birds by altering day length. During each period, we manipulated circulating E2 and examined multiple measures of learning. To manipulate circulating E2, we used subcutaneous implants containing either 17-β E2 and/or fadrozole (FAD), a highly specific aromatase inhibitor that suppresses E2 production in the body and the brain, and measured the latency for birds to learn and respond to short, male conspecific song segments (motifs). We report that photostimulated birds given E2 had higher response rates and responded with better accuracy than those given saline controls or FAD. Conversely, photosensitive, animals treated with E2 responded with less accuracy than those given FAD. These results demonstrate how circulating E2 and photoperiod can interact to shape auditory recognition and learning in adults, driving it in opposite directions in different states. PMID:24058881

  7. Risky business: Is there an association between casual sex and mental health among emerging adults?

    PubMed

    Bersamin, Melina M; Zamboanga, Byron L; Schwartz, Seth J; Donnellan, M Brent; Hudson, Monika; Weisskirch, Robert S; Kim, Su Yeong; Agocha, V Bede; Whitbourne, Susan Krauss; Caraway, S Jean

    2014-01-01

    A multiethnic sample of single, heterosexual, emerging-adult college students (N = 3,907) ages 18 to 25, from 30 institutions across the United States, participated in a study about identity, culture, psychological well-being, and risky behaviors. Given ongoing debates about the connection between casual sex and psychological adjustment, in the current study we assessed the cross-sectional association of participation in casual sex with psychological well-being and distress. A greater proportion of men (18.6%) compared to women (7.4%) reported having had casual sex in the month prior to assessment. Structural equation modeling indicated that casual sex was negatively associated with well-being (ß = .20, p < .001) and positively associated with psychological distress (ß = .16, p < .001). Gender did not moderate these associations. For emerging-adult college students, engaging in casual sex may elevate risk for negative psychological outcomes. PMID:23742031

  8. Sexing adult black-legged kittiwakes by DNA behavior, and morphology

    USGS Publications Warehouse

    Jodice, P.G.R.; Lanctot, Richard B.; Gill, V.A.; Roby, D.D.; Hatch, Shyla A.

    2000-01-01

    We sexed adult Black-legged Kittiwakes (Rissa tridactyla) using DNA-based genetic techniques, behavior and morphology and compared results from these techniques. Genetic and morphology data were collected on 605 breeding kittiwakes and sex-specific behaviors were recorded for a sub-sample of 285 of these individuals. We compared sex classification based on both genetic and behavioral techniques for this sub-sample to assess the accuracy of the genetic technique. DNA-based techniques correctly sexed 97.2% and sex-specific behaviors, 96.5% of this sub-sample. We used the corrected genetic classifications from this sub-sample and the genetic classifications for the remaining birds, under the assumption they were correct, to develop predictive morphometric discriminant function models for all 605 birds. These models accurately predicted the sex of 73-96% of individuals examined, depending on the sample of birds used and the characters included. The most accurate single measurement for determining sex was length of head plus bill, which correctly classified 88% of individuals tested. When both members of a pair were measured, classification levels improved and approached the accuracy of both behavioral observations and genetic analyses. Morphometric techniques were only slightly less accurate than genetic techniques but were easier to implement in the field and less costly. Behavioral observations, while highly accurate, required that birds be easily observable during the breeding season and that birds be identifiable. As such, sex-specific behaviors may best be applied as a confirmation of sex for previously marked birds. All three techniques thus have the potential to be highly accurate, and the selection of one or more will depend on the circumstances of any particular field study. Received 2 February 2000, accepted 1 April 2000.

  9. 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

  10. Anatomically discrete sex differences and enhancement by testosterone of cell proliferation in the telencephalic ventricle zone of the adult canary brain

    PubMed Central

    Barker, Jennifer M.; Ball, Gregory F.; Balthazart, Jacques

    2013-01-01

    Previous work in songbirds has suggested that testosterone increases neuronal recruitment and survival in HVC but does not affect neuronal proliferation in the ventricular zone and that males and females have similar rates of proliferation except at discrete locations. Many of these conclusions are however based on limited data or were inferred indirectly. Here we specifically tested the effects of testosterone on cellular proliferation in the ventricular zone of both male and female adult canaries. We implanted adult birds of both sexes with testosterone or empty implants for one week and injected them with BrdU. One day later, we collected their brains and quantified BrdU-positive cells in the ventricular zone (VZ) at different rostro-caudal levels of the brain, ranging from the level where the song nucleus Area X occurs through the caudal extent of HVC. Proliferation in the dorsal part of the VZ was low and unaffected by sex or testosterone treatment. In the ventral part of the VZ, females had more proliferating cells than males, but only at rostral levels, near Area X. Also in the ventral part of the VZ, testosterone increased proliferation in birds of both sexes, but only in the mid- to caudal-VZ, caudal to the level of Area X, around the septum and HVC. We thus demonstrate here that there is both an effect of testosterone and possibly a more subtle effect of sex on cellular proliferation in the adult songbird brain, and that these effects are specific to different levels of the brain. PMID:24211440

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

    PubMed

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

    1995-07-01

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

  12. Triggering the decision to undergo medical male circumcision: a qualitative study of adult men in Botswana.

    PubMed

    Wirth, Kathleen E; Semo, Bazghina-Werq; Ntsuape, Conrad; Ramabu, Nankie M; Otlhomile, Boyce; Plank, Rebeca M; Barnhart, Scott; Ledikwe, Jenny H

    2016-08-01

    In 2007, the World Health Organization endorsed voluntary medical male circumcision (VMMC) as part of comprehensive HIV-prevention strategies. A major challenge facing VMMC programs in sub-Saharan Africa remains demand creation; there is urgent need for data on key elements needed to trigger the decision among eligible men to seek VMMC. Using qualitative methods, we sought to better understand the circumcision decision-making process in Botswana related to VMMC. From July to November 2013, we conducted 27 focus group discussions in four purposively selected communities in Botswana with men (stratified by circumcision status and age), women (stratified by age) and community leaders. All discussions were facilitated by a trained same-sex interviewer, audio recorded, transcribed and translated to English, and analyzed for key themes using an inductive content analytic approach. Improved hygiene was frequently cited as a major benefit of circumcision and many participants believed that cleanliness was directly responsible for the protective effect of VMMC on HIV infection. While protection against HIV was frequently noted as a benefit of VMMC, the data indicate that increased sexual pleasure and perceived attractiveness, not fear of HIV infection, was an underlying reason why men sought VMMC. Data from this qualitative study suggest that more immediate benefits of VMMC, such as improved hygiene and sexual pleasure, play a larger role in the circumcision decision compared with protection from potential HIV infection. These findings have immediate implications for targeted demand creation and mobilization activities for increasing uptake of VMMC among adult men in Botswana. PMID:26754167

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

    PubMed Central

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

    2007-01-01

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

  14. Prevalent and Incident HIV Diagnoses among Entamoeba histolytica-Infected Adult Males: A Changing Epidemiology Associated with Sexual Transmission — Taiwan, 2006–2013

    PubMed Central

    Lo, Yi-Chun; Ji, Dar-Der; Hung, Chien-Ching

    2014-01-01

    Background Sexually transmitted Entamoeba histolytica infection (EHI) has been increasingly recognized among men who have sex with men (MSM). We used the National Disease Surveillance Systems (NDSS) to identify prevalent and incident HIV diagnoses among adults with EHI and to determine the associated factors. Methodology The NDSS collect demographic, clinical, and behavioral characteristics of case patients through physician reports and public health interviews. EHI was confirmed by polymerase-chain-reaction assays, histopathology, or serology with documented liver abscess. We linked NDSS databases to identify prevalent and incident HIV diagnoses among noninstitutionalized Taiwanese adults with confirmed EHI during 2006–2013. Cox proportional-hazards analysis was used to determine associated factors. Principal findings Of noninstitutionalized adults with EHI, we identified prevalent HIV diagnosis in 210 (40%) of 524 males and one (1.7%) of 59 females, and incident HIV diagnosis in 71 (23%) of 314 males. MSM accounted for 183 (87%) and 64 (90%) of prevalent and incident HIV diagnoses in males, respectively. From 2006–2009 to 2010–2013, the prevalence of HIV diagnosis increased from 32% to 45% (P = 0.001) while the incidence of HIV diagnosis increased from 5.4 to 11.3 per 100 person-years (P = 0.001) among males with EHI. Incident HIV diagnosis was independently associated with a younger age, residing in metropolitan areas, hospitalization, previous syphilis, and engagement in oral, anal, or oral–anal sex before illness onset. Conclusions/significance Prevalent and incident HIV diagnoses were increasingly identified among adult males in Taiwan, preferentially affecting younger urban MSM. Surveillance and risk-reduction interventions are recommended against the interplay of HIV epidemic and sexually transmitted EHI. PMID:25299178

  15. Pornography consumption, cocaine use, and casual sex among U.S. adults.

    PubMed

    Wright, Paul J

    2012-08-01

    This study utilized nationally representative longitudinal survey data from the 2006-2008 General Social Survey (GSS) to explore the interplay between U.S. adults' self-reported past pornography consumption, past cocaine use, and recent participation in casual sex. Participants in the longitudinal component of the 2006-2008 GSS were 867 women and 669 men (N = 1,536) ranging in age from 18 to at least 89 years (M = 45.46; SD = 16.91). Hierarchical logistic regression analysis was employed to analyze the data. After controlling for past casual sex and demographic covariates, the interaction of past pornography consumption and past cocaine use on recent casual sex was significant. Past cocaine users were more likely than non-cocaine users to have had recent casual sex (OR = 4.56), but past pornography consumption was unrelated to recent casual sex for past cocaine users (OR= 0.20). Conversely, past pornography consumption was associated with an increase in the odds of recent casual sex for non-cocaine users (OR = 2.74). PMID:23045873

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

    PubMed Central

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

    2013-01-01

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

  17. Effects of perinatal bisphenol A exposure during early development on radial arm maze behavior in adult male and female rats

    PubMed Central

    Sadowski, Renee N.; Park, Pul; Neese, Steven L.; Ferguson, Duncan C.; Schantz, Susan L.; Juraska, Janice M.

    2014-01-01

    Previous work has shown that exposure to bisphenol A (BPA) can affect anxiety behavior. However, no studies have examined whether administration of this endocrine disruptor during the perinatal period has the potential to induce alterations in cognitive behavior in both adult males and females as assessed in an appetitive task. The goal of the current study was to determine whether exposure to different doses of BPA during early development alters performance on the 17-arm radial maze in adulthood in Long-Evans rats. Oral administration of corn oil (vehicle), 4 μg/kg, 40 μg/kg, or 400 μg/kg BPA to the dams occurred daily throughout pregnancy, and the pups received direct oral administration of BPA between postnatal days 1-9. Blood was collected from offspring at weaning age to determine levels of several hormones (thyroxine, thyroid stimulating hormone, follicle stimulating hormone, luteinizing hormone). One male and one female from each litter were evaluated on the 17-arm radial maze, a working/reference memory task, in adulthood. Results indicated that after exposure to BPA at both 4 and 400 μg/kg/day, rats of both sexes had decreased levels of FSH at weaning. There were no significant effects of BPA on performance on the radial arm maze in males or females. In conclusion, exposure to BPA during early development had modest effects on circulating hormones but did not affect a spatial learning and memory task. PMID:24440629

  18. 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 (Hübner), 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

  19. Sex differences in adult Wistar rats in the voluntary consumption of ethanol after pre-exposure to ethanol-induced flavor avoidance learning.

    PubMed

    de la Torre, M Lourdes; Escarabajal, M Dolores; Agüero, Ángeles

    2015-10-01

    Vulnerability to ethanol abuse may be a function of the balance between the opposing (aversive and rewarding) motivational effects of the drug. The study of these effects is particularly important for understanding alcohol addiction. Research in this field seems to point out that ethanol effects are determined by a set of internal factors (sex, ethanol intake history, etc.), as well as by environmental conditions surrounding the individual (i.e., stress) and, of course, the interactions between all these factors. This work explores sex differences in sensitivity to aversive effects of ethanol using the procedure of flavor avoidance learning (FAL), as well as the effect of this learning experience on subsequent voluntary ethanol consumption, in adult rats. The results obtained indicated a slight sex based difference in the amount of FAL acquired in that females acquisition was weaker (experiment 1), and a differing influence of previous experience with the aversive effects of ethanol on the voluntary consumption of the drug for each sex (experiment 2). In particular, it was observed that female ethanol-naive rats showed a higher intake level and preference for ethanol than both ethanol-experienced female rats and ethanol-naive male rats. In contrast, the ethanol-experienced male rats showed a greater consumption of and preference for ethanol than ethanol-naive