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1

Sex reassignment: Male to female to male  

Microsoft Academic Search

A male patient planned and achieved sex-reassignment surgery which subsequently proved to have been performed prematurely. Postoperatively, the patient experienced a sudden change of conviction and was confronted with the realization that he could not live as a woman. Threatened by suicide, he finally found a resolution to his dilemma by reverting to the male role. Similar mistakes in the

John Money; George Wolff

1973-01-01

2

No attitude, no standing around: the organization of social and sexual interaction at a gay male private sex party in New York city.  

PubMed

Following the onset of the AIDS epidemic, many jurisdictions have outlawed commercial sex-on-premise venues (bathhouses, adult theaters, sex clubs), greatly changing the culture of public or group sex. Today, in New York City (NYC), private sex parties are the main venues for group sex. Dozens of such events are held on a regular basis in the city, attracting sometimes a few hundred participants. Past research in group sex venues shows that different spaces allow for different kinds of sexual and social interaction. What are the norms of interaction of today's private sex parties? This article answers this question by using data collected ethnographically in one recurring gay male private sex party in NYC. The event was a small organization that brought all its participants together in one space at the same time, thus creating great physical intimacy and leading to convivial socialization and interpersonal bonding. This differs from the model of anonymous and impersonal sex that previous researchers have seen in public and commercial spaces. Private sex parties present risk for the transmission of HIV and other sexually-transmitted infections, but their organization and norms of interaction also present new avenues for prevention. Policy-makers should work to make these places safer rather than outlawing them. PMID:23979786

Meunier, Étienne

2014-05-01

3

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

E-print Network

. Bagg concludes, "the results so far indicate that gamma-ray irradiation is a physical agent adapted to the study of experimentally produced developmental arrests in mammalian embryos. " Hanson (1922) reported that male albino rats which were... of radiation on the CNS of gestational period of 1 thru 21 days. The doses used in this study were 100, 200 and 300r X-rays. He also states that, "in the rat and the mouse, whose gestations are about 3 weeks, the embryo as a whole is relatively insensitive...

Ricks, Robert Clinton

2012-06-07

4

Effect of protein malnutrition on sex organs of metanil yellow exposed male rats.  

PubMed

Oral administration of metanil yellow (MY) at 3.0% (w/w) dose level to adult male albino rats maintained on low protein (LP) diet for 30 days resulted in a greater decrease in absolute and relative weights of testes than in those rats maintained on a normal protein (NP) diet. A marked decrease in the activities of lactate dehydrogenase and hyaluronidase and content of lactic acid in LP + MY fed animals suggested that low protein diet enhanced the vulnerability of germ cells towards metanil yellow. The lack of significant changes in the cholesterol content of testis, the fructose content of the coagulating glands and the dorso-lateral prostate, the activities of alkaline phosphatase in the seminal vesicle, and acid phosphatase in ventral prostate of the MY treated animals suggested that their androgenic status were not affected. PMID:9861482

Singh, R L

1998-09-01

5

Effects of perinatal exposure to flutamide on sex hormones and androgen-dependent organs in F1 male rats.  

PubMed

Flutamide, which has antiandrogenic properties, was administered to pregnant rats, and effects on male offspring were examined. Crj: CD (SD) IGS (SPF) females were administered flutamide (0.15, 0.6, 2.5, 10.0, 100 mg/kg, p.o.) from gestation Day 14 to post parturition Day 3. The number of pups, body weights, clinical features, anogenital distance (AGD), nipple retention, testicular descent, and urogenital malformation in F1 males were examined. Hormone measurement, necropsy and histopathological examination were carried out at post-neonatal Day 4 (PND 4) and PND 60. Sperm analysis was also carried out at PND 60. Decrease in body weight was seen in the 100 mg/kg group and the AGD was decreased at 2.5 mg/kg and above. Retention of nipples, hypospadia, vaginal pouches, penis malformation, unilateral ectopic testis, and decrease of organ weights (prostate, seminal vesicles, levator ani muscle plus bulbocavernosus muscle, testis) were observed at 10 mg/kg and above. Testicular testosterone (T) was increased significantly with 100 mg/kg at PND 4 and tendencies for increase were observed in serum T, LH and FSH at 10 mg/kg and more at the same time point. In contrast, elevated levels of LH and FSH were seen with 100 mg/kg at PND 60. Histopathological examination revealed defects or hypoplastic changes of genital organs (> or = 10 mg/kg), squamous metaplasia (10 mg/kg) or mucification (100 mg/kg) of the urethral diverticulum epithelium and inflammation of genital organs (100 mg/kg). Though only undescended testes lacked spermatogenesis at 10 mg/kg, atrophic change of seminiferous tubules and azoospermia were observed in the 100 mg/kg group, despite testicular descent. Perinatal administration of flutamide affected F1 male rats at 2.5 mg/kg and above. In addition to urogenital malformation, 100 mg/kg flutamide caused high LH and FSH levels at PND 60. This study indicates that the most sensitive parameter is AGD, whereby reduction was observed at 2.5 mg/kg. A clear no-effect level (NOEL: 0.6 mg/kg) was obtained in this perinatal study of an antiandrogenic chemical. PMID:11915366

Miyata, Kaori; Yabushita, Setsuko; Sukata, Tokuo; Sano, Masashi; Yoshino, Hiroko; Nakanishi, Takumi; Okuno, Yasuyoshi; Matsuo, Masatoshi

2002-02-01

6

Sex Bias in Traditionally Male Occupational Programs.  

ERIC Educational Resources Information Center

To evaluate potential sources of female sex bias and sex stereotyping within traditionally male occupational programs at the College of DuPage, programs with low female enrollment were selected for study: air conditioning and refrigeration, architectural drafting, auto service, building construction, criminal justice, electronics, fire science,…

Bakshis, Robert; Godshalk, James

7

Sex steroid actions in male bone.  

PubMed

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-? 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

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

2014-12-01

8

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

PubMed Central

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

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

2013-01-01

9

Human male meiotic sex chromosome inactivation.  

PubMed

In mammalian male gametogenesis the sex chromosomes are distinctive in both gene activity and epigenetic strategy. At first meiotic prophase the heteromorphic X and Y chromosomes are placed in a separate chromatin domain called the XY body. In this process, X,Y chromatin becomes highly phosphorylated at S139 of H2AX leading to the repression of gonosomal genes, a process known as meiotic sex chromosome inactivation (MSCI), which has been studied best in mice. Post-meiotically this repression is largely maintained. Disturbance of MSCI in mice leads to harmful X,Y gene expression, eventuating in spermatocyte death and sperm heterogeneity. Sperm heterogeneity is a characteristic of the human male. For this reason we were interested in the efficiency of MSCI in human primary spermatocytes. We investigated MSCI in pachytene spermatocytes of seven probands: four infertile men and three fertile controls, using direct and indirect in situ methods. A considerable degree of variation in the degree of MSCI was detected, both between and within probands. Moreover, in post-meiotic stages this variation was observed as well, indicating survival of spermatocytes with incompletely inactivated sex chromosomes. Furthermore, we investigated the presence of H3K9me3 posttranslational modifications on the X and Y chromatin. Contrary to constitutive centromeric heterochromatin, this heterochromatin marker did not specifically accumulate on the XY body, with the exception of the heterochromatic part of the Y chromosome. This may reflect the lower degree of MSCI in man compared to mouse. These results point at relaxation of MSCI, which can be explained by genetic changes in sex chromosome composition during evolution and candidates as a mechanism behind human sperm heterogeneity. PMID:22355370

de Vries, Marieke; Vosters, Sanne; Merkx, Gerard; D'Hauwers, Kathleen; Wansink, Derick G; Ramos, Liliana; de Boer, Peter

2012-01-01

10

More Than a Sex Machine: Accomplishing Masculinity Among Chinese Male Sex Workers in the Hong Kong Sex Industry  

Microsoft Academic Search

Situated in the masculinity and deviance literature, this article examines a “deviant” masculinity, that of the male sex worker, and presents the ways men who engage in sex work cope with the job. Based on in-depth interviews of Chinese male sex workers (n = 18) in the Hong Kong sex industry, I argue that the stigma management techniques these men employ are

Travis S. K. Kong

2009-01-01

11

Understanding the New Context of the Male Sex Work Industry  

ERIC Educational Resources Information Center

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…

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

2005-01-01

12

Masculinity and Relationship Agreements among Male Same-Sex Couples  

Microsoft Academic Search

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

Christopher W. Wheldon; Elizabeth B. Pathak

2010-01-01

13

Male Sex Work: Exploring Regulation in England and Wales  

Microsoft Academic Search

Whilst sex-work policy in England and Wales claims gender-neutrality, local and national prostitution strategies primarily focus on female street-based sex workers. Men who sell sex are generally absent or inadequately considered in such policies, and measures to regulate commercial sex markets are rarely considered in terms of their impact on male working practice. Drawing on the Coordinated Prostitution Strategy for

M ary W howell

2010-01-01

14

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

Microsoft Academic Search

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

Roxana Torres; Hugh Drummond

1999-01-01

15

Effect of the ethanolic extract from Fagara tessmannii on testicular function, sex reproductive organs and hormone level in adult male rats.  

PubMed

The effect of ethanolic extract of Fagara tessmannii, wide medicinal plants used on reproductive function in South Cameroon, was investigated in male rats. Twenty male sexually experienced rats (four groups) were orally treated with vehicle, 0.01, 0.1, 1 g kg(-1) BW per day of F. tessmannii (equivalent to 16.67 g, 33.33 g, 50 g, 66.66 g kg(-1) dry raw material) for 14 days, the upper limit dose without any clinical sign of toxicity was 2 g kg(-1). Fagara tessmannii extract negatively affected weight of accessory organs and significantly affected body weight gain at dose 1 g kg(-1) (P < 0.05) in treated rats. The weight of epididymis and seminal vesicle significantly decreased at low doses (0.01 g kg(-1)) while the prostate weight decreased at all doses (P < 0.05). The transit of spermatozoa in cauda epididymidis significantly increased at lower dose of 0.01 g kg(-1) (P < 0.05). In addition, F. tessmannii extract affected neither daily sperm production (DSP) and DSP per g nor sperm count in vas deferens and epididymis. The length of stages IX-I of the seminiferous tubule and serum testosterone level increased dose-dependently following 14 days of treatment (P < 0.05). The results suggest that F. tessmannii, 14 days after treatment, may improve spermatogenesis, testosterone level and sperm transit in cauda epididymidis but negatively impair reproductive organ activities. PMID:21382068

Massoma Lembè, D; Gasco, M; Rubio, J; Yucra, S; Sock, E Ngo; Gonzales, G F

2011-04-01

16

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

PubMed

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

Torres, R; Drummond, H

1999-01-01

17

Sex or Food? Appetetive Learning of Sex Odors in a Male Moth  

NASA Astrophysics Data System (ADS)

Moths learn to associate a flower odor with a food reward after a few learning trials. Can a hungry, male moth learn to associate a sex attractant with food instead of with sex? We provided a hungry male with odors of single female sex pheromone components, of the full sex pheromone blend or of a flower odor component as cues in an appetitive learning assay. The male learned the single pheromone components just as well as the flower odor. Learning was, however, severely impaired when the full sex pheromone blend was used as conditioning stimulus. The "hard-wiring" between pheromone odor and sex thus seems to be restricted to those circumstances when the male moth experiences the full blend.

Hartlieb, Elke; Hansson, Bill S.; Anderson, Peter

18

Family Support Tied to Safer Sex for Young Gay Males  

MedlinePLUS

... Family Support Tied to Safer Sex for Young Gay Males: Study Closeness, open discussions with parents may ... October 15, 2014 Related MedlinePlus Pages Family Issues Gay, Lesbian, Bisexual and Transgender Health Teen Sexual Health ...

19

Group Work Practice with Transgendered Male to Female Sex Workers.  

ERIC Educational Resources Information Center

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,…

Klein, Rebecca

1999-01-01

20

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

PubMed Central

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

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

2014-01-01

21

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

PubMed

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

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

2014-01-01

22

Perceived male sex orientation and beliefs about rape  

Microsoft Academic Search

This paper examines the relationship between male sex role orientation and beliefs in rape myths. Five variables were controlled: religious belief (fundamentalist), academic interest (nonarts and arts), sister relationship, and maternal employment. Data were collected by means of a questionnaire mailed to 400 male college students randomly chosen from selected academic areas. Tests of correlation were used to analyze these

Alyce B. Bunting; Joy B. Reeves

1983-01-01

23

Distinguishing Characteristics Of Male And Female Child Sex Abusers  

Microsoft Academic Search

This study examines child sexual abuser stereotypes by exploring the relationships among gender, gender role identity, emotional need, and sexual need in adult relationships of child sexual abusers and nonabusers. The sample consists of 71 male and 58 female offenders, and 38 male and 52 female nonoffenders. Masculinity and femininity are measured by the Bem Sex Role Inventory, and emotional

Craig M. Allen; Henry L. Pothast

1994-01-01

24

Sexual systems and dwarf males in barnacles: integrating life history and sex allocation theories.  

PubMed

Barnacles, which are sedentary marine crustaceans, have diverse sexual systems that include simultaneous hermaphroditism, androdioecy (coexistence of hermaphrodites and males) and dioecy (females and males). In dioecious and androdioecious species, the males are very small and are thus called dwarf males. These sexual systems are defined by two factors: sex allocation of non-dwarf individuals and the presence or absence of dwarf males. We constructed an ESS model treating sex allocation and life history simultaneously to explain sexual systems in barnacles. We analyzed the evolutionarily stable size-dependent resource allocation strategy to male reproductive function, female reproductive function and growth in non-dwarf barnacles, and the ESS proportion of dwarf males, under conditions of varying mortality and food availability. Sex allocation in non-dwarf individuals (hermaphrodites or females) is affected by mate availability and the proportion of dwarf males. When hermaphrodites appear, all hermaphrodites become protandric simultaneous hermaphrodites. Furthermore, high mortality and poor resource availability favor dwarf males because of their early maturation and weakened sperm competition. In conclusion, we showed that combining sex allocation and life history theories is a useful way to understand various sexual systems in barnacles and perhaps in other organisms as well. PMID:23238283

Yamaguchi, Sachi; Yusa, Yoichi; Sawada, Kota; Takahashi, Satoshi

2013-03-01

25

A comparison of sex offenders against female and male minors.  

PubMed

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

Freund, K; Watson, R; Rienzo, D

1987-01-01

26

Tactics for male reproductive success in plants: contrasting insights of sex allocation theory and pollen presentation theory  

Microsoft Academic Search

Synopsis The basic tenet of sex allocation theory is that an organism's reproductive success, through either male or female function, can be represented as a sex-specific, monotonic, increasing function ofthe organism'sinvestment ofresources inthat function. The shapes of these curves determine what patterns of resource allocation can be evolutionarily stable. Although SA theory has stimulated creative thinking about plant sexual tactics,

James D. Thomson

2006-01-01

27

Socially-Responsive Gene Expression in Male Drosophila melanogaster Is Influenced by the Sex of the Interacting Partner  

PubMed Central

Behavior is influenced by an organism's genes and environment, including its interactions with same or opposite sex individuals. Drosophila melanogaster perform innate, yet socially modifiable, courtship behaviors that are sex specific and require rapid integration and response to multiple sensory cues. Furthermore, males must recognize and distinguish other males from female courtship objects. It is likely that perception, integration, and response to sex-specific cues is partially mediated by changes in gene expression. Reasoning that social interactions with members of either sex would impact gene expression, we compared expression profiles in heads of males that courted females, males that interacted with other males, or males that did not interact with another fly. Expression of 281 loci changes when males interact with females, whereas 505 changes occur in response to male–male interactions. Of these genes, 265 are responsive to encounters with either sex and 240 respond specifically to male–male interactions. Interestingly, 16 genes change expression only when a male courts a female, suggesting that these changes are a specific response to male–female courtship interactions. We supported our hypothesis that socially-responsive genes can function in behavior by showing that egghead (egh) expression, which increases during social interactions, is required for robust male-to-female courtship. We predict that analyzing additional socially-responsive genes will give us insight into genes and neural signaling pathways that influence reproductive and other behavioral interactions. PMID:20980240

Ellis, Lisa L.; Carney, Ginger E.

2011-01-01

28

Socially-responsive gene expression in male Drosophila melanogaster is influenced by the sex of the interacting partner.  

PubMed

Behavior is influenced by an organism's genes and environment, including its interactions with same or opposite sex individuals. Drosophila melanogaster perform innate, yet socially modifiable, courtship behaviors that are sex specific and require rapid integration and response to multiple sensory cues. Furthermore, males must recognize and distinguish other males from female courtship objects. It is likely that perception, integration, and response to sex-specific cues is partially mediated by changes in gene expression. Reasoning that social interactions with members of either sex would impact gene expression, we compared expression profiles in heads of males that courted females, males that interacted with other males, or males that did not interact with another fly. Expression of 281 loci changes when males interact with females, whereas 505 changes occur in response to male-male interactions. Of these genes, 265 are responsive to encounters with either sex and 240 respond specifically to male-male interactions. Interestingly, 16 genes change expression only when a male courts a female, suggesting that these changes are a specific response to male-female courtship interactions. We supported our hypothesis that socially-responsive genes can function in behavior by showing that egghead (egh) expression, which increases during social interactions, is required for robust male-to-female courtship. We predict that analyzing additional socially-responsive genes will give us insight into genes and neural signaling pathways that influence reproductive and other behavioral interactions. PMID:20980240

Ellis, Lisa L; Carney, Ginger E

2011-01-01

29

Male-to-Female Sex Reassignment Surgery in Transsexuals  

Microsoft Academic Search

The technique of male-to-female sex reassignment surgery in a sample of 500 patients is described in detail and illustrated by 27 figures. Appropriate technique and care results in a naturally looking vulva and a functioning vagina. The complication rate is low, and most complications can be overcome by adequate correctional interventions.

Christiane Spehr

2007-01-01

30

Male prostitutes and safe sex: Different settings, different risks  

Microsoft Academic Search

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

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

1994-01-01

31

MEANS OF DESIRE'S PRODUCTION: MALE SEX LABOR IN CUBA  

Microsoft Academic Search

Tourism has provided myriad spaces in which black Cuban subjects participate in self-making, yet within a field still constrained by historical structures of sexual and racial interpellation. This essay focuses on the local social cultural context of male sex labor in Havana, Cuba, from 1998 to 2003. It explores the subjective intentions of young Cuban men during the Special Period

Jafari Sinclaire Allen

2007-01-01

32

Economic Transition, Male Competition, and Sex Differences in Mortality  

Microsoft Academic Search

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

Daniel J. Kruger; Randolph M. Nesse

2007-01-01

33

Regulation of male sex determination: genital ridge formation and Sry activation in mice.  

PubMed

Sex determination is essential for the sexual reproduction to generate the next generation by the formation of functional male or female gametes. In mammals, primary sex determination is commenced by the presence or absence of the Y chromosome, which controls the fate of the gonadal primordium. The somatic precursor of gonads, the genital ridge is formed at the mid-gestation stage and gives rise to one of two organs, a testis or an ovary. The fate of the genital ridge, which is governed by the differentiation of somatic cells into Sertoli cells in the testes or granulosa cells in the ovaries, further determines the sex of an individual and their germ cells. Mutation studies in human patients with disorders of sex development and mouse models have revealed factors that are involved in mammalian sex determination. In most of mammals, a single genetic trigger, the Y-linked gene Sry (sex determination region on Y chromosome), regulates testicular differentiation. Despite identification of Sry in 1990, precise mechanisms underlying the sex determination of bipotential genital ridges are still largely unknown. Here, we review the recent progress that has provided new insights into the mechanisms underlying genital ridge formation as well as the regulation of Sry expression and its functions in male sex determination of mice. PMID:25139092

Tanaka, Satomi S; Nishinakamura, Ryuichi

2014-12-01

34

Introduction Sex is determined in many organisms by an X-chromosome  

E-print Network

6519 Introduction Sex is determined in many organisms by an X-chromosome counting mechanism that distinguishes one X chromosome from two (e.g. XO male/XX female in nematodes) or by the presence of a specific sex chromosome, such as the Y chromosome (e.g. XY male/XX female in mammals) (Meller and Kuroda, 2002

Meyer, Barbara

35

Male-biased reproduction and sex-ratio adjustment in muskrats  

Microsoft Academic Search

Sex ratios of a population and of litters were sampled in muskrats in Ontario, Canada. Sex ratios of litters sampled from nests were male biased (54% male). Until weaning, no differential costs of producing and rearing male and female young were identified that could account for this greater production of males. Following weaning, however, male-biased dispersal of juveniles from their

M. J. Caley; S. Boutin; R. A. Moses

1988-01-01

36

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

PubMed Central

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

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

2013-01-01

37

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

PubMed

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

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

2008-01-01

38

Patterns of abuse in male same-sex relationships.  

PubMed

Previous studies of abuse in male same-sex relationships have been limited by convenience samples and/or by incomplete assessments of partner abuse. We examined patterns of same-sex partner abuse in a random sample of 284 gay and bisexual men. Respondents reported on perpetration and receipt of physical, psychological, and sexual abuse over multiple time frames, as well as injuries resulting from abuse. Almost all respondents reported psychological abuse, more than one-third reported physical abuse, and 10% reported having engaged in unwanted sexual activity because of partner force or threats of force. More than half of recipients of partner violence reported sustaining injury. We found strong associations between different forms of abuse, and between severity of abuse receipt and perpetration. PMID:18958989

Bartholomew, Kim; Regan, Katherine V; White, Monica A; Oram, Doug

2008-01-01

39

Male rarity and putative sex-role reversal in Fijian damselflies (Odonata)  

Microsoft Academic Search

Behavioural sex-role reversal occurs when males and females exchange their standard roles in territorial defence or parental care. One circumstance under which sex-role reversal may occur is when males are a limiting resource, so that females have to compete for access to mates. Here we report on male rarity and male and female behaviour of species within the damselfly genus

Hans Van Gossum; Christopher D. Beatty; Sylvain Charlat; Hilda Waqa; Timothy Markwell; Jeffrey H. Skevington; Marika Tuiwawa; Thomas N. Sherratt

2007-01-01

40

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

Microsoft Academic Search

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

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

2004-01-01

41

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

PubMed

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

Parker, M Rockwell; Mason, Robert T

2012-03-01

42

Male breast cancer, age and sex chromosome aneuploidy  

PubMed Central

Background: In cultured, dividing transformed T lymphocytes and in dividing bone marrow cells from normal men and those with a haematological malignancy, sex chromosome aneuploidy has been found to increase in prevalence and degree with age. This has rarely been investigated in non-dividing uncultured blood samples. The loss and gain of the X chromosome in dividing transformed lymphocytes in women with age is much more frequent than that of the Y chromosome in males. However, paradoxically X chromosome aneuploidy is rarely seen in the dividing cells of bone marrow of females. Methods: In blood samples from 565 men with breast cancer and 54 control men from the England and Wales general population, 80 cell nuclei per sample were scored for presence of X and Y chromosomes using fluorescent centromeric probes. Results: Sex chromosome aneuploidy, largely Y chromosome loss, was present in 63% of cases and 57% of controls, with the prevalence and degree of aneuploidy increasingly sharply and highly significantly with age. At ages 65–80 years, 71% of cases and 85% of controls showed aneuploidy and 15% and 25%, respectively, had ?10% of cells aneuploid. Allowing for age, aneuploidy was less prevalent (P=0.03) in cases than controls. Conclusion: Sex chromosome aneuploidy in non-dividing nuclei of peripheral blood cells is frequent in adult men, the prevalence and degree increasing sharply with age. The possible relation of sex chromosome aneuploidy to breast cancer risk in men, and to cancer risk generally, needs further investigation, ideally in cohort studies. PMID:23299533

Jacobs, P A; Maloney, V; Cooke, R; Crolla, J A; Ashworth, A; Swerdlow, A J

2013-01-01

43

Researching Non-Governmental Strategies for Male Sex Workers' Empowerment in Northern Thailand  

Microsoft Academic Search

This paper reports the methodological insights derived from a research trip undertaken to study the existing non-governmental strategies for male sex workers? empowerment in Northern Thailand. My research was concerned with determining whether NGOs can effectively provide an alternative to the governmental programs, in order to meet the needs of Thai male sex workers. Although the topic of sex work

Simona-Gabriela Gavrila

2008-01-01

44

Psychological androgyny, sex-typing, and sex-role ideology as predictors of male-female interpersonal attraction  

Microsoft Academic Search

Two studies examined the degree of sex-typing or androgyny college students desired in their ideal dating partners\\/potential spouses. In Study I, 140 males and 95 females classified according to psychological sex type rated their ideal partners on the items of the Bem Sex Role Inventory (BSRI). Consistent with the general tenor of predictions, sex-typed subjects endorsed a greater discrepancy between

Jacob L. Orlofsky

1982-01-01

45

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

PubMed

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

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

1994-01-01

46

Male Sex Workers Who Sell Sex to Men Also Engage in Anal Intercourse with Women: Evidence from Mombasa, Kenya  

PubMed Central

Objective To investigate self-report of heterosexual anal intercourse among male sex workers who sell sex to men, and to identify the socio-demographic characteristics associated with practice of the behavior. Design Two cross-sectional surveys of male sex workers who sell sex to men in Mombasa, Kenya. Methods Male sex workers selling sex to men were invited to participate in surveys undertaken in 2006 and 2008. A structured questionnaire administered by trained interviewers was used to collect information on socio-demographic characteristics, sexual behaviors, HIV and STI knowledge, and health service usage. Data were analyzed through descriptive and inferential statistics. Bivariate logistic regression, after controlling for year of survey, was used to identify socio-demographic characteristics associated with heterosexual anal intercourse. Results From a sample of 867 male sex workers, 297 men had sex with a woman during the previous 30 days – of whom 45% did so with a female client and 86% with a non-paying female partner. Within these groups, 66% and 43% of male sex workers had anal intercourse with a female client and non-paying partner respectively. Factors associated with reporting recent heterosexual anal intercourse in bivariate logistic regression after controlling for year of survey participation were being Muslim, ever or currently married, living with wife only, living with a female partner only, living with more than one sexual partner, self-identifying as basha/king/bisexual, having one’s own children, and lower education. Conclusions We found unexpectedly high levels of self-reported anal sex with women by male sex workers, including selling sex to female clients as well as with their own partners. Further investigation among women in Mombasa is needed to understand heterosexual anal sex practices, and how HIV programming may respond. PMID:23300978

Mannava, Priya; Geibel, Scott; King'ola, Nzioki; Temmerman, Marleen; Luchters, Stanley

2013-01-01

47

A Psychosocial Study of Male-to-Female Transgendered and Male Hustler Sex Workers in São Paulo, Brazil  

Microsoft Academic Search

This study examined sociodemographic variables, personality characteristics, and alcohol and drug misuse among male sex workers\\u000a in the city of Santo André, São Paulo, Brazil. A total of 45 male-to-female transgender sex workers and 41 male hustlers were\\u000a evaluated in face-to-face interviews at their place of work from 2008 to 2010. A “snowball” sampling procedure was used to\\u000a access this

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

48

Sex differences in student dominance behavior in female and male professors' classrooms  

Microsoft Academic Search

Measures of verbal participation and interaction among graduate students provided a comparison of male and female dominance behavior in the classroom, and measures of the contextual effect of sex of professor provided further data on the interrelatedness of sex, status, and dominance behavior. Male students were found to exhibit significantly more aggressiveness (interruptive behavior) than female students in both male

Virginia R. Brooks

1982-01-01

49

Offspring sex ratio is unrelated to male attractiveness in dark-eyed juncos ( Junco hyemalis )  

Microsoft Academic Search

Sex allocation theory predicts that parents should bias investment toward the offspring sex that confers higher relative fitness on the parents. When variance in reproductive success is higher in males than females, and some males are more attractive to females than others, thereby achieving higher reproductive success, female parents mated to attractive males are expected to bias reproductive allocation toward

Jennifer L. Grindstaff; Alex C. Buerkle; Joseph M. Casto; Val Nolan Jr; Ellen D. Ketterson

2001-01-01

50

The influence of sex-role stereotypes on evaluations of male and female supervisory behavior  

Microsoft Academic Search

Examined the way sex-role stereotypes influence evaluations of male and female supervisory behavior. 134 male and 24 female undergraduates and 83 male and 15 female bank supervisors were asked to read 1 of 6 versions of a supervisory problem (with either a male or female supervisor and male, female, or mixed subordinates), and evaluate the effectiveness of 4 supervisory styles.

Benson Rosen; Thomas H. Jerdee

1973-01-01

51

RACE OF MALE SEX PARTNERS AND OCCURRENCE OF BACTERIAL VAGINOSIS  

PubMed Central

BACKGROUND Whether bacterial vaginosis (BV) is sexually transmitted is uncertain. Also it is unknown why BV is approximately twice as prevalent among African-American as among white women. An association of BV with a characteristic of the male sex partner, such as race, might support sexual transmission as well as account for the observed ethnic disparity in BV. METHODS 3620 non-pregnant women 15–44 years of age were followed quarterly for 1 year. At each visit, extensive questionnaire data and vaginal swabs for Gram’s staining were obtained. The outcome was transition from BV-negative to positive (Nugent’s score ?7) in an interval of 2 consecutive visits. RESULTS BV occurred in 12.8% of 906 sexually active intervals to white women- 24.8% of intervals when the woman reported an African-American partner and 10.7% when all partners were white. Among white women, there was a two-fold increased risk for BV incidence with an African-American, compared with a white partner (risk ratio (RR) 2.3, 95% confidence interval (CI) 1.6–3.4; adjusted RR 2.2, 95% CI 1.5–3.4), but differed according to condom use. In the presence of consistent condom use, the adjusted RR was 0.7 (0.3–2.4); it was 2.4 (1.0–6.2) in the presence of inconsistent use; and 2.7 (1.7–4.2) in the absence of condom use. African-American women could not be studied, as there were insufficient numbers who reported only white male sex partners. CONCLUSION The association of BV occurrence with partner’s race, and its blunting by condom use, suggests that BV may have a core group component and may be sexually transmitted. PMID:19959972

Klebanoff, Mark A.; Andrews, William W.; Zhang, Jun; Brotman, Rebecca M.; Nansel, Tonja R.; Yu, Kai-Fun; Schwebke, Jane R.

2009-01-01

52

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

Microsoft Academic Search

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

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

2007-01-01

53

Personality Characteristics of Male Clients of Female Commercial Sex Workers in Australia  

Microsoft Academic Search

The personality characteristics of male clients of female sex workers and their motivations for seeking the services of sex workers were examined. It was hypothesized that clients of sex workers would differ from nonclients in that they would adopt less feminine sex roles, exhibit lower social–sexual effectiveness, and show higher levels of sensation-seeking behavior. Sixty-six clients of sex workers and

Luke Xantidis; Marita P. McCabe

2000-01-01

54

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

E-print Network

Dancing in the DomeMales are lured byfood and sex into erotic contests and deadly brawls by Paul J. The males are not only looking for mates; they are also searching for food. Without a female's web in which

Watson, Paul J.

55

Male and female careers: Sex-role and occupational stereotypes among high school students  

Microsoft Academic Search

The present study combined two areas of research, occupational perceptions and sex-role stereotypes, in a 2 (Gender of Subject: male, female) × 2 (Gender of Character: male, Paul or David; female, Paula or Susan) × 2 (Gender of Occupation: male, doctor or lawyer; female, nurse or secretary) between-subjects factorial design. High school students rated male and female characters in traditional

Sylvia Lifschitz

1983-01-01

56

Cuticular lipids and odors induce sex-specific behaviors in the male cricket Gryllus bimaculatus  

Microsoft Academic Search

Male crickets display sex-specific (e.g., mating and agonistic) behaviors towards conspecific individuals. One of the key signals for these behaviors is the chemical substance on the cricket body surface. In the present study, we analyzed female and male cuticular substances in behavioral assays. Antennal contact stimulation using female forewings elicited a mating behavior in males, while that using male forewings

Masazumi Iwasaki; Chihiro Katagiri

2008-01-01

57

The Prevalence of Depression in Male Sex Addicts Residing in the United States  

Microsoft Academic Search

This study evaluated the prevalence of depression among male sex addicts against the general male population. This research utilized the high estimate of 12% for male depression in the general population as reported by the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 2000). This research had 418 participants, 220 of whom qualified as male sexual addicts residing

DOUGLAS WEISS

2004-01-01

58

Sex Chromosome-Specific Regulation in the Drosophila Male Germline But Little Evidence for Chromosomal  

E-print Network

Sex Chromosome-Specific Regulation in the Drosophila Male Germline But Little Evidence for Chromosomal Dosage Compensation or Meiotic Inactivation Colin D. Meiklejohn*, Emily L. Landeen, Jodi M. Cook, United States of America Abstract The evolution of heteromorphic sex chromosomes (e.g., XY in males or ZW

Dean, Matthew D.

59

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

ERIC Educational Resources Information Center

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…

Freeman, Naomi J.; Sandler, Jeffrey C.

2008-01-01

60

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

Microsoft Academic Search

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

Yasmina Katsulis; Alesha Durfee

2012-01-01

61

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

ERIC Educational Resources Information Center

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…

Vandiver, Donna M.

2006-01-01

62

A Prospective Analysis of Juvenile Male Sex OffendersCharacteristics and Recidivism Rates as Adults  

Microsoft Academic Search

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

Donna M. Vandiver

2006-01-01

63

Sex role orientations of male and female collegiate athletes from selected individual and team sports  

Microsoft Academic Search

The purpose of the present study was to determine whether the sex role orientations of male and female collegiate athletes were more similar in team sports than in individual sports. It was predicted that females in masculine-oriented team sports (basketball and volleyball) would exhibit sex role orientations more similar to those of their male counterparts than would females in individual

Craig A. Wrisberg; M. Vanessa Draper; John J. Everett

1988-01-01

64

ORIGINAL PAPER Do sex-changing male snails use mate choice to get a jump  

E-print Network

, it is a common and obvious trait for male choice; size preference has been observed in species from fish (Ptacek are protandrous sequential hermaphrodites, species that change sex from male to female as they grow. Protandrous sequential hermaphrodites are by the nature of their sex change sexually size dimorphic, with large

65

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

ERIC Educational Resources Information Center

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)

Yarber, William L.; Yee, Bernadette

1983-01-01

66

Preventing behavioural interactions with a male facilitates sex change in female bluebanded gobies, Lythrypnus dalli  

Microsoft Academic Search

Sex change in marine teleost fishes is commonly regulated by social factors. In species that exhibit protogynous sex change,\\u000a such as the bluebanded goby Lythrypnus dalli, the most dominant female typically initiates sex change when a male is removed from the social group. Females can use visual,\\u000a chemical or tactile cues to assess the presence or absence of a male.

Varenka Lorenzi; Ryan L. Earley; Matthew S. Grober

2006-01-01

67

Brood sex ratio and male UV ornamentation in blue tits ( Cyanistes caeruleus ): correlational evidence and an experimental test  

Microsoft Academic Search

Sex-allocation theory predicts that females paired to attractive males should bias the brood sex ratio towards male offspring,\\u000a as these would inherit the attractiveness of their father. We studied sex allocation based on male ornamentation in blue tits.\\u000a Brood sex ratios varied with male UV coloration in an age-dependent manner. For juvenile males, the proportion of sons increased\\u000a with increasing

Kaspar Delhey; Anne Peters; Arild Johnsen; Bart Kempenaers

2007-01-01

68

Fluorochemicals used in food packaging inhibit male sex hormone synthesis  

SciTech Connect

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

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

2013-01-01

69

MMPI Profiles of Males with Abnormal Sex Chromosome Complements  

ERIC Educational Resources Information Center

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

Rosen, M.; And Others

1971-01-01

70

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

PubMed Central

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

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

2013-01-01

71

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

PubMed

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

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

2013-01-01

72

The Social Organization of Commercial Sex Work in Moscow  

Microsoft Academic Search

Background: Increased poverty, unemployment, and migration place the Russian population at high risk for sexually transmitted infections (STIs). A qualitative study was undertaken to clarify the organization of sex work and describe the likely contributions of different types of sex work to disease transmission. Goal: The goal of the study was to describe the social-organiza- tional patterns of sex work

SEVGI O. ARAL; LILIA TIKHONOVA; EMMA SAFAROVA; KATHLEEN A. PARKER; ANNA SHAKARISHVILI; CAROLINE A. RYAN

73

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

E-print Network

20, 2005) The adult sex ratio (ASR) is a key parameter of the demography of human and other animal population extinction sexual coercion The adult sex ratio (ASR) is a central concept of population demography of understanding the popu- lation consequences of ASR variation has attracted much atten- tion from human

Alvarez, Nadir

74

Transactional sex risk and STI among HIV-infected female sex workers and HIV-infected male clients of FSWs in India  

Microsoft Academic Search

To describe sex risk behaviors of HIV-infected female sex workers (FSWs) and HIV-infected male clients of FSWs, to evaluate associations between risky transactional sex and number of unprotected transactional sex episodes, and to assess the association between unprotected transactional sex and self-reported sexually transmitted infection (STI). Adult HIV-infected FSWs (n=211) and HIV-infected male clients (n=205) were surveyed in Mumbai about

Anita Raj; N. Saggurti; Debbie M. Cheng; Anindita Dasgupta; Carly Bridden; Manojkumar Pradeshi; J. H. Samet

2011-01-01

75

Sex-reversed mice: XX and XO males  

Microsoft Academic Search

An autosomally inherited condition is described in the mouse which causes genetic females to develop as phenotypic males. XX males are phenotypically normal with the exception of small testes, which, in the adult, are devoid of germ cells. During late fetal and early postnatal development, male-type germ cells are present but progressively become lost, so that none is present by

B. M. Cattanach; C. E. Pollard; S. G. Hawkes

1971-01-01

76

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

PubMed

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

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

2013-01-01

77

The Profile and Treatment of Male Adolescent Sex Offenders.  

ERIC Educational Resources Information Center

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,…

Lakey, Joyce F.

1994-01-01

78

Loss of Sex-Specific Difference in Femoral Bone Parameters in Male Leptin Knockout Mice  

Microsoft Academic Search

Sex-dependent differences were identified in the femoral bone parameters of male and female ob\\/ob (leptin knockout) mice compared with their C57BL\\/6 wild-type background strain. Total fat, lean weight and body weight were\\u000a not different between adult male and female leptin knockout mice. However, leptin knockout males exhibited lower lean weights\\u000a than C57BL\\/6 males. Peripheral quantitative computerized tomographic measurements at the

Xiaoguang Wang; Charles H. Rundle; Jon E. Wergedal; Apurva K. Srivastava; Subburaman Mohan; K.-H. William Lau

2007-01-01

79

Causes of a male-biased operational sex ratio in the fiddler crab Uca crenulata  

Microsoft Academic Search

  \\u000a This research investigates the causes of a male-biased operational sex ratio in a population of the California fiddler crab, Uca crenulata. Mensurative studies revealed there were almost twice as many adult males as females, mating occurred across half of the\\u000a days within the breeding season, and females had much longer individual reproductive cycles than males. Therefore, many more\\u000a males

Catherine E. deRivera

2003-01-01

80

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

PubMed Central

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-?-farnesene and E-?-farnesene, both richer in females than males, might be putative female pheromones. PMID:18515819

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

2008-01-01

81

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

ERIC Educational Resources Information Center

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

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

2002-01-01

82

Change of the heterogametic sex from male to female in the frog.  

PubMed

Two different types of sex chromosomes, XX/XY and ZZ/ZW, exist in the Japanese frog Rana rugosa. They are separated in two local forms that share a common origin in hybridization between the other two forms (West Japan and Kanto) with male heterogametic sex determination and homomorphic sex chromosomes. In this study, to find out how the different types of sex chromosomes differentiated, particularly the evolutionary reason for the heterogametic sex change from male to female, we performed artificial crossings between the West Japan and Kanto forms and mitochondrial 12S rRNA gene sequence analysis. The crossing results showed male bias using mother frogs with West Japan cytoplasm and female bias using those with Kanto cytoplasm. The mitochondrial genes of ZZ/ZW and XX/XY forms, respectively, were similar in sequence to those of the West Japan and Kanto forms. These results suggest that in the primary ZZ/ZW form, the West Japan strain was maternal and thus male bias was caused by the introgression of the Kanto strain while in the primary XX/XY form and vice versa. We therefore hypothesize that sex ratio bias according to the maternal origin of the hybrid population was a trigger for the sex chromosome differentiation and the change of heterogametic sex. PMID:12807781

Ogata, M; Ohtani, H; Igarashi, T; Hasegawa, Y; Ichikawa, Y; Miura, I

2003-06-01

83

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

Microsoft Academic Search

We used radioimmunoassay (RIA) to measure monthly serum levels of unconjugated and conjugated sex steroids (testosterone T, androstenedione A, estradiol E2, and estrone E1) in 4 male and 4 female foals during their first year of life. Maximal production of sex steroids was detected from April to August with hormonal peaks, corresponding to the natural breeding season in adults. In

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

2002-01-01

84

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

E-print Network

; fishing; hermaphroditism; protandry; protogyny; shrimp. Correspondence Philip P. Molloy, DepartmentPredicting the effects of exploitation on male-first sex-changing fish P. P. Molloy1,2 , N. B:10.1111/j.1469-1795.2006.00065.x Abstract Sex change is widespread among tropical marine fishes, many

Reynolds, John D.

85

Short day lengths skew prenatal sex ratios toward males in Siberian hamsters.  

PubMed

For decades, researchers have documented significant skews in the production of male versus female offspring in many species. Because males and females are differentially susceptible to environmental challenges and also represent different fitness benefits, it may be beneficial to exert control over the offspring sex ratio when environmental conditions become challenging. Some of the most dramatic environmental challenges occur on a seasonal basis. Indeed, seasonal variation in offspring sex ratios has been documented in both mammalian and nonmammalian species. The seasonal environmental factor (or factors) that drives the skews in sex ratios is unknown; however, it is essential that such a cue be predictable and reliable and that it does not vary from year to year. We hypothesized that photoperiod, a stable cue of seasonal changes in temperature and resource availability, may underlie seasonal variation in offspring sex ratios of mammals. We predicted that short day lengths in particular, which signal impending winter conditions and related energetic demands, would stimulate an anticipatory skew in the offspring sex ratio. We used Siberian hamsters as models because they are phenotypically responsive to photoperiod but up to 60% of females continue to breed during the winter. The sexes of weanling hamsters conceived and raised in short, winter like day lengths were significantly skewed toward males. Furthermore, these skews occurred before birth; embryos collected from pregnant females maintained in short-day conditions were also significantly male biased. Thus, photoperiod functions as an effective seasonal cue, stimulating sex ratio skews toward males when day lengths are short. PMID:19938980

Navara, Kristen J; Workman, Joanna L; Oberdick, John; Nelson, Randy J

2010-01-01

86

Local resource competition and the evolution of male-biased sex ratios.  

PubMed

In many mammalian species, maturing males disperse from their natal groups, while females remain near their places of birth. If sources are limited locally, related females may be forced to compete with one another for access to resources, while mature males will compete primarily with unrelated individuals in non-natal groups. Clark (1978) suggested that under such circumstances the extent of competition among females could be reduced if females uniformly skewed the sex ratio of their offspring in favor of males. Skewed secondary sex ratios and investment patterns in galagos and red deer appear to be consistent with this hypothesis. Several authors have recently demonstrated that the evolution of skewed sex ratios may be influenced by population structure, and Wilson & Colwell (1981) have shown that male-biased sex ratios can evolve in structured haplodiploid populations. Here, I construct an intrademic group selection model to simulate the effects of density-dependent mortality upon diploid populations structured much as Clark describes: males disperse, females remain near their female relatives, and local resource competition limits the size of local groups. The results confirm that male-biased sex ratios can evolve in a diploid species, even when groups are large and the skew in sex ratio is substantial. PMID:6748687

Silk, J B

1984-05-21

87

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

PubMed

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

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

2005-11-01

88

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

Microsoft Academic Search

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

Karen Jacques; Paul J. Taylor

2008-01-01

89

Sexually dimorphic neurons in the ventromedial hypothalamus govern mating in both sexes and aggression in males  

PubMed Central

SUMMARY Sexual dimorphisms in the brain underlie behavioral sex differences, but the function of individual sexually dimorphic neuronal populations is poorly understood. Neuronal sexual dimorphisms typically represent quantitative differences in cell number, gene expression, or other features, and it is unknown if these dimorphisms control sex-typical behavior in one sex exclusively or in both sexes. The progesterone receptor (PR) controls female sexual behavior, and we find many sex differences in number, distribution, or projections of PR-expressing neurons in the adult mouse brain. We have ablated one such PR-expressing neuronal population located in the ventromedial hypothalamus (VMH) using a novel genetic strategy. Ablation of these neurons in females greatly diminishes sexual receptivity. Strikingly, the corresponding ablation in males reduces mating and aggression. Our findings reveal the functions of a molecularly-defined, sexually dimorphic neuronal population in the brain. Moreover we show that sexually dimorphic neurons can control distinct sex-typical behaviors in both sexes. PMID:23663785

Yang, Cindy F.; Chiang, Michael; Gray, Daniel C.; Prabhakaran, Mahalakshmi; Alvarado, Maricruz; Juntti, Scott A.; Unger, Elizabeth K.; Wells, James A.; Shah, Nirao M.

2013-01-01

90

Persistent organic pollutants and male reproductive health  

PubMed Central

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

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

2014-01-01

91

Sex hormones and male homosexuality in comparative perspective  

Microsoft Academic Search

Animal research has demonstrated the modifiability of sex-dimorphic mating behavior by hormone and brain manipulation, especially in subprimate mammals, and has led to radical attempts at treating human homosexuality by psychosurgery and to the suggestion of preventing homosexuality by prenatal hormone manipulation. This article reviews psychoendocrine studies of human homosexuality — the effects of hormone treatments on sexual orientation, the

Heino F. L. Meyer-Bahlburg

1977-01-01

92

One-Stage Sex Reassignment Surgery from Female to Male  

Microsoft Academic Search

In this paper we try to give a detailed description of the one-step sex reassignment surgery performed by Dr. Daverio and Dr. Krueger successfully more than 350 times. The surgery itself consists of several steps: the removal of the mammae, the uterus, the adnexes, the ovaries and the vagina, the prolongation of the urethra, the creation of a sensate neo-phallus

Michael Krueger; S. Ali Haschemi Yekani; Georg v. Hundt; Paul J. Daverio

2007-01-01

93

Same-Sex Rape of Male College Students  

Microsoft Academic Search

Rape of men by other men is a widely neglected yet increasingly recognized form of sexual assault. Information on same-sex rape involving men is frequently absent in campus rape education and prevention programming because the general public and popular culture have traditionally viewed rape in a context of violence against women. Available medical and psychological literature indicates the need for

Michael Scarce

1997-01-01

94

Motivational Counseling: Implications for Counseling Male Juvenile Sex Offenders  

ERIC Educational Resources Information Center

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…

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

2008-01-01

95

Male Psychosexual Development: Role of Sibling Sex and Ordinal Position  

ERIC Educational Resources Information Center

The present study was designed to investigate the hypothesis that in two-sibling families the presence of an older sister is related to the younger brother's subsequent sexual behavior, sexual interests, attitudes, and problems as measured by a self-report sex questionnaire. (Authors)

Kahn, Michael H.; And Others

1972-01-01

96

Effects Produced on Rats by Synthetic Androsteron (Male Sex Hormone)  

Microsoft Academic Search

AT the request of Prof. Ruzicka, I undertook the experimental investigation on male and female rats of the biological properties of androsteron and some of his other allied synthetic preparations. The following are the first results with androsteron.

V. Korenchevsky

1935-01-01

97

Sex Chromosome  

NSDL National Science Digital Library

A sex chromosome is one of the two chromosomes that specify an organism's genetic sex. Humans have two kinds of sex chromosomes, one called X and the other Y. Normal females possess two X chromosomes and normal males one X and one Y.

Darryl Leja (National Human Genome Research Institute REV)

2005-04-14

98

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

Microsoft Academic Search

This study sought to determine if there was a relationship between heterosexuals' attitudes toward lesbianism and male homosexuality and their affective orientation toward sexuality (erotophiliaerotophobia) and sex guilt. Subjects were 72 male and 57 female heterosexual college undergraduates. A self-report questionnaire was administered in a health education class and mailed to campus dormitories. The variables were measured by four scales:

William L. Yarber; Bernadette Yee

1983-01-01

99

Sex differences in scent-marking in sifaka: Mating conflict or male services?  

Microsoft Academic Search

Male and female interests can either be in conflict or serve as a basis for exchange. Communication is thus an important aspect of intersexual relationships. Verreaux's sifaka (Propithecus verreauxi verreauxi), like many prosimians, uses chemical signals as one form of communication. The goals of this study were to determine 1) if males and females exhibit sex differences in their scent-marking

Rebecca J. Lewis

2005-01-01

100

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

ERIC Educational Resources Information Center

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

Gutek, Barbara A.; Stevens, Denise A.

101

Offspring sex ratio allocation in the parasitic jaeger: selection for pale females and melanic males?  

Microsoft Academic Search

The maintenance of plumage color polymorphism in the parasitic jaeger (Stercorarius parasiticus) is still not well understood. Earlier studies indicated that selection may favor pale females and melanic males. If so, females would maximize their fitness, producing pale female and melanic male offspring. We therefore predicted that females might bias their offspring sex ratio toward daughters in pale pairs and

Kirstin Janssen; Kjell Einar Erikstad; Staffan Benschc

2005-01-01

102

Offspring sex ratio allocation in the parasitic jaeger: selection for pale females and melanic males?  

Microsoft Academic Search

The maintenance of plumage color polymorphism in the parasitic jaeger (Stercorarius parasiticus) is still not well understood. Earlier studies indicated that selection may favor pale females and melanic males. If so, females would maximize their fitness, producing pale female and melanic male offspring. We therefore predicted that females might bias their offspring sex ratio toward daughters in pale pairs and

Kirstin Janssen; Kjell Einar Erikstad; Staffan Bensch

2006-01-01

103

Transgenerational Epigenetic Imprinting of the Male Germline by Endocrine Disruptor Exposure during Gonadal Sex Determination  

Microsoft Academic Search

Embryonic exposure to the endocrine disruptor vinclozolin at the time of gonadal sex determination was previously found to promote transgenerational disease states. The actions of vinclozolin appear to be due to epigenetic alterations in the male germline that are transmitted to subsequent genera- tions. Analysis of the transgenerational epigenetic effects on the male germline (i.e. sperm) identified 25 candidate DNA

Hung-Shu Chang; Matthew D. Anway; Stephen S. Rekow; Michael K. Skinner

2006-01-01

104

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

PubMed Central

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

Bar-Johnson, Michael; Weiss, Petr

2014-01-01

105

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

Microsoft Academic Search

The HIV epidemic among men who have sex with men (MSM) in China is becoming very serious. Unprotected anal intercourse (UAI) among MSM during cross-boundary commercial sex spread HIV across geographic areas. This study interviewed 186 Chinese male sex workers (MSW) in Shenzhen, China, serving cross-boundary Hong Kong male clients; 49.5% had had UAI with their Hong Kong male clients

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

2011-01-01

106

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

Microsoft Academic Search

The HIV epidemic among men who have sex with men (MSM) in China is becoming very serious. Unprotected anal intercourse (UAI) among MSM during cross-boundary commercial sex spread HIV across geographic areas. This study interviewed 186 Chinese male sex workers (MSW) in Shenzhen, China, serving cross-boundary Hong Kong male clients; 49.5% had had UAI with their Hong Kong male clients

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

2012-01-01

107

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

PubMed Central

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

H.W. Biedermann, Peter

2010-01-01

108

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

PubMed

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

H W Biedermann, Peter

2010-01-01

109

Sex steroid hormones enhance immune function in male and female Siberian hamsters  

Microsoft Academic Search

Bilbo, Staci D., and Randy J. Nelson. Sex steroid hor-mones enhance immune function in male and female Sibe-rian hamsters. Am J Physiol Regulatory Integrative Comp Physiol 280: R207?R213, 2001.DImmune function is better in females than in males of many vertebrate species, and this dimorphism has been attributed to the presence of immuno-suppressive androgens in males. We investigated the in?u-ence of

STACI D. BILBO; RANDY J. NELSON

110

Male Sex Interspecies Divergence and Down Regulation of Expression of Spermatogenesis Genes in Drosophila Sterile Hybrids  

Microsoft Academic Search

Male sex genes have shown a pattern of rapid interspecies divergence at both the coding and gene expression level. A common\\u000a outcome from crosses between closely-related species is hybrid male sterility. Phenotypic and genetic studies in Drosophila sterile hybrid males have shown that spermatogenesis arrest is postmeiotic with few exceptions, and that most misregulated\\u000a genes are involved in late stages

Vignesh Sundararajan; Alberto Civetta

2011-01-01

111

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

Microsoft Academic Search

Male sex workers are a highly marginalised group in Hong Kong and it is increasingly so with an influx of them travelling from mainland China to work as “freelance” sex workers. This study aimed to measure important work environment variables that might affect the likelihood of condom use among male sex workers working in Hong Kong. A cross-sectional survey of

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

2012-01-01

112

Factors distinguishing homosexual males practicing risky and safer sex  

Microsoft Academic Search

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

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

1989-01-01

113

Gadd45g Is Essential for Primary Sex Determination, Male Fertility and Testis Development  

PubMed Central

In humans and most mammals, differentiation of the embryonic gonad into ovaries or testes is controlled by the Y-linked gene SRY. Here we show a role for the Gadd45g protein in this primary sex differentiation. We characterized mice deficient in Gadd45a, Gadd45b and Gadd45g, as well as double-knockout mice for Gadd45ab, Gadd45ag and Gadd45bg, and found a specific role for Gadd45g in male fertility and testis development. Gadd45g-deficient XY mice on a mixed 129/C57BL/6 background showed varying degrees of disorders of sexual development (DSD), ranging from male infertility to an intersex phenotype or complete gonadal dysgenesis (CGD). On a pure C57BL/6 (B6) background, all Gadd45g?/? XY mice were born as completely sex-reversed XY-females, whereas lack of Gadd45a and/or Gadd45b did not affect primary sex determination or testis development. Gadd45g expression was similar in female and male embryonic gonads, and peaked around the time of sex differentiation at 11.5 days post-coitum (dpc). The molecular cause of the sex reversal was the failure of Gadd45g?/? XY gonads to achieve the SRY expression threshold necessary for testes differentiation, resulting in ovary and Müllerian duct development. These results identify Gadd45g as a candidate gene for male infertility and 46,XY sex reversal in humans. PMID:23516551

Johnen, Heiko; González-Silva, Laura; Carramolino, Laura; Flores, Juana Maria; Torres, Miguel; Salvador, Jesús M.

2013-01-01

114

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

PubMed Central

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

Li, Qing; Li, Xiaoming; Stanton, Bonita

2010-01-01

115

Sex Reassignment Surgery in the Female-to-Male Transsexual  

PubMed Central

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

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

2011-01-01

116

SEX-ROLE SELF-CONCEPTS OF HOMOSEXUAL MEN AND THEIR ATTITUDES TOWARD BOTH WOMEN AND MALE HOMOSEXUALITY  

Microsoft Academic Search

A no clinical sample of 88 homosexual males responded to a questionnaire that assessed their sex-role self-concept and their attitudes toward both women and male homosexuality. Results indicated that in terms of socially valued masculine and feminine characteristics, the majority of homosexual males viewed themselves as predominantly androgynous. These respondents also favored equality between the sexes, reflecting posit vive attitudes

Gary J. McDonald; Robert J. Moore

1978-01-01

117

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

Microsoft Academic Search

Where both sexes invest substantially in o¡spring, 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 bene¢ts to be gained. We measured o¡spring quality from experimentally staged matings with preferred and non-preferred partners in a sex-role-reversed pipe¢sh, Syngnathus typhle L. Here, a

Maria Sandvik; Gunilla Rosenqvist; Anders Berglund

2000-01-01

118

Transactional sex risk and STI among HIV-infected female sex workers and HIV-infected male clients of FSWs in India.  

PubMed

To describe sex risk behaviors of HIV-infected female sex workers (FSWs) and HIV-infected male clients of FSWs, to evaluate associations between risky transactional sex and number of unprotected transactional sex episodes, and to assess the association between unprotected transactional sex and self-reported sexually transmitted infection (STI). Adult HIV-infected FSWs (n = 211) and HIV-infected male clients (n = 205) were surveyed in Mumbai about demographics, STI, and past 90-day and past year sex and substance use histories. Gender-stratified Poisson regression models were used to evaluate associations between four risky transactional sex behaviors (number of transactional sex partners; alcohol use before transactional sex; anal transactional sex; and transactional sex with a known HIV-infected partner) and number of unprotected transactional sex episodes; logistic regression was used to assess the association between unprotected transactional sex and self-reported STI. Twenty-nine percent of females and 7% of males reported any unprotected transactional sex episodes in the past 90 days. Thirty-nine percent of females and 12% of males reported past year STI. Among males, a greater number of transactional sex partners was associated with more unprotected transactional sex episodes (adjusted incidence rate ratio [IRR] = 8.2, 95% confidence interval [CI] = 1.8-38.4 highest vs. lowest tertile), and any unprotected transactional sex was associated with a higher odds of self-reported STI in the past year (adjusted odds ratio [AOR] = 5.6, 95% CI = 1.4-22.4). For women, risky transactional sex behaviors were not associated with condom non-use, and unprotected sex was negatively associated with STI (AOR = 0.4, 95% CI = 0.2-0.9). Reports of condom use during transactional sex were high for these samples. However, standard predictors of unprotected transactional sex (i.e., greater number of partners) and STI (i.e., unprotected sex) only held true for males. Further research is needed to guide an understanding of sex risk and STI among HIV-infected FSWs in India. PMID:21711167

Raj, Anita; Saggurti, N; Cheng, Debbie M; Dasgupta, Anindita; Bridden, Carly; Pradeshi, Manojkumar; Samet, J H

2011-11-01

119

XXXY sex chromosomes in males of the jumping spider genus Pellenes (Araneae: Salticidae)  

Microsoft Academic Search

Observations of male meiosis and female chromosome number indicate that eight species of Pellenes have the X1X2O male, X1X1X2X2 female sex chromosome system typical of salticids, four species have an X'1X'2X'3Y male, X'1X'1X'2X'3X'3X'3 female system, and one species has both X1X2O and X'1X'2X'3Y males. This is the first report of a Y chromosome in spiders. It is hypothesized that the

Wayne Paul Maddison; S IA

1982-01-01

120

HIV, syphilis infection, and sexual practices among transgenders, male sex workers, and other men who have sex with men in Jakarta, Indonesia  

Microsoft Academic Search

Objectives: To establish the prevalence of HIV, syphilis, and sexual risk behaviour among three groups of men who have sex with men in Jakarta, Indonesia, and to investigate sexual links between these men and broader heterosexual populations.Methods: Anonymous, cross sectional surveys among community recruited transgender and male sex workers and self recognised men who have sex with men (MSM) were

E Pisani; P Girault; M Gultom; N Sukartini; J Kumalawati; S Jazan; E Donegan

2004-01-01

121

Sex pheromone components of male Tirathaba mundella (Lepidoptera: Pyralidae)  

Microsoft Academic Search

Summary.   During peak calling activity by male oil palm bunch\\u000a moths, Tirathaba mundella Walker (Lepidoptera: Pyralidae), their\\u000a hairpencils, wings or entire body were extracted in hexane. Gas\\u000a chromatographic-electroantennographic detection (GC-EAD) analyses of\\u000a hair pencil extracts revealed four compounds that consistently elicited\\u000a responses from female antennae. The NMR spectrum of isolated compound 1,\\u000a and mass spectra and retention indices of compounds

Yorianta Sasaerila; Regine Gries; Gerhard Gries; Grigori Khaskin; Skip King; Stephen Takács

2003-01-01

122

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

PubMed Central

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

Sandvik, M; Rosenqvist, G; Berglund, A

2000-01-01

123

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

PubMed

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

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

2014-07-01

124

Aggressive females become aggressive males in a sex-changing reef fish.  

PubMed

Many animal populations display consistent individual differences in suites of correlated behaviours. While these so called 'animal personalities' can substantially influence the ecology and evolution of populations, little is known about cross-sex correlations of behaviour and thus the potential of personality to limit sex-specific behavioural adaptations. Here, we experimentally induced sex-change in the sequentially hermaphroditic reef fish Parapercis cylindrica and demonstrate the existence of tight cross-sex correlations for two behaviours with presumed different sex-specific optima. Individuals that were relatively more active and aggressive females were found to become relatively more active and aggressive males. By identifying personality as a potential genetic constraint on the resolution of intralocus sexual conflict over behaviour, our findings have important ecological and evolutionary implications for a wide range of species. PMID:22731810

Sprenger, Dennis; Dingemanse, Niels J; Dochtermann, Ned A; Theobald, Jennifer; Walker, Stefan P W

2012-09-01

125

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

PubMed Central

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 microhabitat use under a male-biased sex ratio. Consistent with surveys showing reduced detection probabilities for females, our research suggests that females avoid male encounters using edge and substrate habitat. Our work illustrates the integrated suite of impacts that sexual conflict can have on the structure and ecology of a population. PMID:22988835

2012-01-01

126

Organizing Effects of Sex Steroids on Brain Aromatase Activity in Quail  

PubMed Central

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

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

2011-01-01

127

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

PubMed

Bacterial endosymbionts that manipulate host reproduction are now known to be widespread in insects and other arthropods. Since they inhabit the cytoplasm and are maternally inherited, these microorganisms can enhance their fitness by biasing host sex ratio in favour of females. At its most extreme, sex ratio manipulation may be achieved by killing male embryos, as occurs in a number of insect species. Here, we provide evidence for the first case of male killing by a tetracycline-sensitive microbe in pseudoscorpions. Using a combination of inheritance studies, antibiotic treatment and molecular assays, we show that a new strain of Wolbachia is associated with extreme female bias in the pseudoscorpion, Cordylochernes scorpioides. In a highly female-biased line, sex ratio distortion was maternally inherited, and occurred in conjunction with a high rate of spontaneous abortion and low reproductive success. Antibiotic treatment cured females of the Wolbachia infection, restored offspring sex ratio to 1:1, and significantly enhanced female reproductive success. The discovery of apparent male-killing in C. scorpioides is of interest because pseudoscorpions are viviparous. Theory predicts that male killing should be favoured, if male death enhances the fitness of infected female siblings. In a live-bearing host, reallocation of maternal resources from dead male embryos to their sisters provides a direct, physiological mechanism through which fitness compensation could favour male killing by cellular endosymbionts. Our results suggest, however, that fitness compensation and the spread of male-killing endosymbionts may be undermined by a high rate of spontaneous abortion in infected females of this viviparous arthropod. PMID:15931253

Zeh, D W; Zeh, J A; Bonilla, M M

2005-07-01

128

Identification of DNA markers linked to the male sex in dioecious hemp (Cannabis sativa L.)  

Microsoft Academic Search

A 400-bp RAPD marker generated by a primer of random decamer sequence has been found associated with the male sex phenotype\\u000a in 14 dioecious cultivars and accessions of hemp (Cannabis sativa L.). The primer OPA8 generates a set of bands, most of which polymorphic among all the individual plants tested, and 1 of\\u000a which, named OPA8400, present in all male

G. Mandolino; A. Carboni; S. Forapani; V. Faeti; P. Ranalli

1999-01-01

129

HIV Prevention Needs Among Street-Based Male Sex Workers in Providence, Rhode Island.  

PubMed

We examined data derived from a needs assessment of the personal and social characteristics and HIV risk behavior of street-based male sex workers, in Providence, Rhode Island, who engage in transactional sexual intercourse with other men. Substance use, injected drugs, needle sharing, and psychosocial distress were highly prevalent among the sample. History of physical, sexual, and emotional abuse was associated with increased risk of condomless anal sexual intercourse with paying male clients. PMID:25211761

Landers, Stewart; Closson, Elizabeth F; Oldenburg, Catherine E; Holcomb, Richard; Spurlock, Shannon; Mimiaga, Matthew J

2014-11-01

130

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

Microsoft Academic Search

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

A Ziersch; J Gaffney; D R Tomlinson

2000-01-01

131

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

Microsoft Academic Search

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

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

2000-01-01

132

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

ERIC Educational Resources Information Center

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…

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

2011-01-01

133

Surgical treatment of locally advanced anal cancer after male-to-female sex reassignment surgery  

Microsoft Academic Search

We present a case of a transsexual patient who under- went a partial pelvectomy and genital reconstruction for anal cancer after chemoradiation. This is the first case in literature reporting on the occurrence of anal cancer after male-to-female sex reassignment surgery. We describe the surgical approach presenting our technique to avoid postoperative complications and preserve the sexual reassignment.

Marco Caricato; Fabio Ausania; Giovanni Francesco Marangi; Ilaria Cipollone; Gerardo Flammia; Paolo Persichetti; Lucio Trodella; Roberto Coppola

2009-01-01

134

Homosexual and bisexual identity in sex-reassigned female-to-male transsexuals  

Microsoft Academic Search

Descriptions of female-to-male transsexuals who are sexually attracted to men are rare. This is a report on nine of them. Their awareness of gender dysphoria preceded their awareness of their attraction to men. Their wish to undergo sex reassignment as a means of resolving their gender dysphoria superseded any concerns about their sexual orientation or sexual adaptation after surgery. Several

Eli Coleman; Walter O. Bockting; Louis Gooren

1993-01-01

135

Factors Associated with Satisfaction or Regret Following Male-to-Female Sex Reassignment Surgery  

Microsoft Academic Search

This study examined factors associated with satisfaction or regret following sex reassignment surgery (SRS) in 232 male-to-female transsexuals operated on between 1994 and 2000 by one surgeon using a consistent technique. Participants, all of whom were at least 1-year postoperative, completed a written questionnaire concerning their experiences and attitudes. Participants reported overwhelmingly that they were happy with their SRS results

Anne A. Lawrence

2003-01-01

136

Male Use of Female Sex Work in India: A Nationally Representative Behavioural Survey  

Microsoft Academic Search

Heterosexual transmission of HIV in India is driven by the male use of female sex workers (FSW), but few studies have examined the factors associated with using FSW. This nationally representative study examined the prevalence and correlates of FSW use among 31,040 men aged 15–49 years in India in 2006. Nationally, about 4% of men used FSW in the previous

Michelle F. Gaffey; Srinivasan Venkatesh; Neeraj Dhingra; Ajay Khera; Rajesh Kumar; Paul Arora; Nico Nagelkerke; Prabhat Jha

2011-01-01

137

Efficacy of Nonpsychopharmacological Treatment for Male Sex Offenders: A Review of the Literature.  

ERIC Educational Resources Information Center

Sexual offenses have a serious impact on individuals and society at large. Most victims know the offender; few victims report the offense; not all reports result in arrests; not all arrests result in conviction; and not all convictions result in incarceration. This paper reviews the literature related to psychotherapeutic treatment of male sex…

Moorhead, Douglas A.

138

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

ERIC Educational Resources Information Center

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…

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

2013-01-01

139

Short Day Lengths Skew Prenatal Sex Ratios Toward Males in Siberian Hamsters  

E-print Network

000 Short Day Lengths Skew Prenatal Sex Ratios Toward Males in Siberian Hamsters * Corresponding. Navara1, * Joanna L. Workman2 John Oberdick3,4 Randy J. Nelson2,3 1 Department of Poultry Science, 203 Poultry Science Building, University of Georgia, Athens, Georgia 30602; 2 Department of Psychology, Ohio

Navara, Kristen

140

HIV risk profile of male street youth involved in survival sex  

Microsoft Academic Search

Objectives: To compare HIV risk factors of male street youth involved in survival sex with those of their never involved peers and to describe the sexual activities of the involved youths.Methods: From 2001 to 2003, street youth aged 14–23 years were recruited from street youth agencies in Montreal, Canada. Information was collected on sociodemographic characteristics, substance use, and sexual behaviours.

N Haley; E Roy; P Leclerc; J-F Boudreau; J-F Boivin

2004-01-01

141

Issues in the assessment and treatment of male sex offenders with mild learning disabilities  

Microsoft Academic Search

The psychological assessment and treatment of male sex offenders has been of increasing interest in recent years, and a substantial literature, primarily cognitive-behavioural in orientation, now exists. However, there is little information about the application of this literature to men with mild learning disabilities (previously known as mild ‘mental handicap’), who have impaired intellectual and social functioning and are at

Isabel C. H. Clare

1993-01-01

142

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

ERIC Educational Resources Information Center

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

Adams, Carol; Sherer, Mark

143

An exploration of elevated HIV and STI risk among male sex workers from India  

PubMed Central

Background Men who have sex with men (MSM) who also report transactional sex (male sex workers or MSWs) are known to be at higher risk for HIV and sexually transmitted infections (STIs). The study aimed to profile socio-demographic characteristics and risk factors associated with high HIV prevalence among MSWs. Methods A cross-sectional study was conducted in 2008–9 among 483 high-risk MSM who attended STI clinics at Mumbai and Hyderabad, two large cities in India. Results About 70% of the MSM reported transactional sex. As compared to other MSM, MSWs had more male partners (8.9 versus 2.5, p?sex (96% versus 72%, p?sex work (increased by 8% for every additional year). Conclusion The study showed that MSWs are at high risk for HIV acquisition/transmission, which highlights the need for intensified interventions for personalized risk-reduction counselling and STI screening. Newer biomedical interventions such as pre-exposure prophylaxis and treatment as prevention could also be considered. PMID:24209579

2013-01-01

144

Differential sex allocation in sand lizards: bright males induce daughter production in a species with heteromorphic sex chromosomes.  

PubMed

In sand lizards (Lacerta agilis), males with more and brighter nuptial coloration also have more DNA fragments visualized in restriction fragment length polymorphism analysis of their major histocompatibility complex class I loci (and, hence, are probably more heterozygous at these loci). Such males produce more viable offspring, with a particularly strong viability effect on daughters. This suggests that females should adjust both their reproductive investment and offspring sex ratio in relation to male coloration (i.e. differential allocation). Our results show that experimental manipulation of partner coloration in the wild results in significantly higher maternal effort and a 10% higher proportion of daughters than sons. This supports the hypothesis that females increase their maternal energetic expenditure and adjust their offspring sex ratio in response to high-quality partners. However, it also suggests that this has probably evolved through natural selection for increased offspring viability (primarily through production of daughters), rather than through increased mate attraction (e.g. sexy sons). PMID:17148211

Olsson, Mats; Wapstra, Erik; Uller, Tobias

2005-09-22

145

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

PubMed Central

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

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

2012-01-01

146

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

PubMed Central

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

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

2003-01-01

147

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

PubMed

A survey of sex and birth control behavior of 51 male adolescents aged 15-17 was conducted utilizing a structured interview protocol. The sample was drawn from 3 community agencies. The respondents resided in a major northeastern metropolitan part of Pennsylvania. The purpose of the study was to describe male adolescent birth control behavior incorporating developmental issues, and to interpret the findings in light of what is known about female birth control behavior. Based on research with teenage females, 3 social influences were examined for their possible impact on male birth control behavior. An interview schedule was undertaken to form the basis of the demographic items, the description of the social network, history of sex and birth control behavior, pregnancy history and communication about sex and birth control. A questionnaire, designed to measure the influence of significant others on females' birth control behavior, formed the basis of the items concerning the expectations of others about contraceptive behavior. Thirdly, questions on perceived power relations with girlfriends were used to determin the influence of teenage females' self-perceptions of power in dyadic relationships on their own contraceptive usage. A new operational definition of male effective birth control usage involving the effectiveness of the method and the consistency of its usage was developed. Findings similar to those obtained in the research on females suggest that adolescent sexual partners may be the only direct social influence on adolescents' birth control usage. Results indicating differences from research with females suggest that in general: male birth control behavior is primarily self-oriented, males are more likely to be effective contraceptors with casual partners than with girlfriends, males are more likely to communicate about sex and birth control with similar age peers than with family members and/or other adults, and that teen males view sex and birth control decisions as female decisions. Only 35.3% of the males showed a full understanding of how pregnancy occurs. For coitally active subjects, the more the topic of communication was specifically sexual in content, the more likely it was for the subject to speak to similar-aged people and friends than to adults. PMID:12339898

Cohen, D D; Rose, R D

1984-06-01

148

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

Microsoft Academic Search

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

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

2006-01-01

149

Handedness, Functional Cerebral Hemispheric Lateralization, and Cognition in Male-to-Female Transsexuals Receiving Cross-Sex Hormone Treatment  

Microsoft Academic Search

This study examined the impact of sex hormones on functional cerebral hemispheric lateralization and cognition in a group of male-to-female transsexuals receiving cross-sex hormone therapy compared to eugonadal men with a male gender identity. Cerebral lateralization was measured with a handedness questionnaire and a visual-split-field paradigm and cognitive tests sensitive to sex hormone exposure (identical pictures, 3-D mental rotation, building

Amy B. Wisniewski; Mary T. Prendeville; Adrian S. Dobs

2005-01-01

150

Sex chromosome polymorphism and heterogametic males revealed by two cloned DNA probes in the ZW\\/ZZ fish Leporinus elongatus  

Microsoft Academic Search

In order to study the divergence of teleost sex chromosomes, subtractive cloning was carried out between genomic DNA of males and females of the rainbow trout (XX\\/XY) and of Leporinus elongatus (ZW\\/ZZ). Inserts cloned in a plasmid vector were individually tested on Southern blots of DNA of males and females for sex specificity. No sex-specific insert was obtained from trout,

Ichiro Nakayama; Fausto Foresti; Rita Tewari; Manfred Schartl; Daniel Chourrout

1994-01-01

151

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

PubMed

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

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

2002-04-01

152

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

PubMed Central

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

2014-01-01

153

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

PubMed

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

Campbell, D R

1998-09-01

154

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

Microsoft Academic Search

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

Grit A. Glawe; Tom J. de Jong

2005-01-01

155

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

Microsoft Academic Search

Unprotected heterosexual transactional sex plays a central role in the spread of HIV in India. Given alcohol’s association\\u000a with risky sex in other populations and alcohol’s role in HIV disease progression, we investigated patterns of alcohol use\\u000a in HIV-infected female sex workers (FSWs) and HIV-infected male clients of FSWs in Mumbai. Analyses identified factors associated\\u000a with heavy alcohol use and

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

2010-01-01

156

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

PubMed Central

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

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

2013-01-01

157

Think Leader, Think Male and Female: Sex vs. Seating Arrangement as Leadership Cues  

Microsoft Academic Search

This investigation challenged the long-accepted male-oriented ideology of “think male, think leader” by using social and gender\\u000a identity theoretical frameworks to examine same-gender biases and the situational leadership cue of the end-of-the-table position.\\u000a In an experiment consisting of 241 undergraduates enrolled in a large southwestern university in the U.S. (105 men, 135 women,\\u000a and 1 sex unreported), participants viewed diagrams

Danielle Jackson; Erika Engstrom; Tara Emmers-Sommer

2007-01-01

158

Sex Differences in Adults’ Relative Visual Interest in Female and Male Faces, Toys, and Play Styles  

Microsoft Academic Search

An individual’s reproductive potential appears to influence response to attractive faces of the opposite sex. Otherwise, relatively\\u000a little is known about the characteristics of the adult observer that may influence his or her affective evaluation of male\\u000a and female faces. An untested hypothesis (based on the proposed role of attractive faces in mate selection) is that most women\\u000a would show

Gerianne M. Alexander; Nora Charles

2009-01-01

159

Sexuality Before and After Male-to-Female Sex Reassignment Surgery  

Microsoft Academic Search

The sexual behaviors and attitudes of male-to-female (MtF) transsexuals have not been investigated systematically. This study presents information about sexuality before and after sex reassignment surgery (SRS), as reported by 232 MtF patients of one surgeon. Data were collected using self-administered questionnaires. The mean age of participants at time of SRS was 44 years (range, 18–70 years). Before SRS, 54%

Anne A. Lawrence

2005-01-01

160

Violence and HIV Sexual Risk Behaviors Among Female Sex Partners of Male Drug Users  

Microsoft Academic Search

Objective: Violence and HIV are emerging as interconnected public health hazards among drug users and their families. The purposes of this study are to (1) determine the prevalence of sexual and physical abuse of non-drug-using female sex partners of male drug users, and (2) ascertain the association between such violence and HIV-related risk behaviors. Methods: From 11\\/93 to 11\\/95, 208

Haiou He; H. Virginia McCoy; Sally J. Stevens; Michael J. Stark

1998-01-01

161

Patient-Reported Complications and Functional Outcomes of Male-to-Female Sex Reassignment Surgery  

Microsoft Academic Search

This study examined preoperative preparations, complications, and physical and functional outcomes of male-to-female sex reassignment\\u000a surgery (SRS), based on reports by 232 patients, all of whom underwent penile-inversion vaginoplasty and sensate clitoroplasty,\\u000a performed by one surgeon using a consistent technique. Nearly all patients discontinued hormone therapy before SRS and most\\u000a reported that doing so created no difficulties. Preoperative electrolysis to

Anne A. Lawrence

2006-01-01

162

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

E-print Network

- rone; testosterone; synapse; memory It is well accepted that males and females can behave differentlySex Differences and Opposite Effects of Stress on Dendritic Spine Density in the Male Versus Female of intermittent tailshocks, spine density was enhanced in the male hippocampus but reduced in the female

Shors, Tracey J.

163

A sex-determining region on the Y chromosome controls the sex-reversal ratio in interspecific hybrids between Oryzias curvinotus females and Oryzias latipes males.  

PubMed

Oryzias latipes and Oryzias curvinotus are closely related medaka species that have the common sex-determining gene, DMY, on their homologous Y chromosomes. We previously reported that sex-reversed XY females were produced in hybrids between O. curvinotus females and O. latipes males (Hd-rR inbred strain). In this study we used HNI inbred strain males of O. latipes for mating with O. curvinotus females, and found that all the XY hybrids developed as males. To map the factor responsible for this strain-specific XY sex reversal, O. curvinotus females were mated with two Y-congenic strains (HNI.Y(Hd-rR) and Hd-rR.Y(HNI)) and a recombinant congenic strain (Hd-rR.Y(HNI)rr). HNI.Y(Hd-rR) produced sex-reversed females in the XY hybrids, whereas no sex-reversed females were obtained in the XY hybrids from Hd-rR.Y(HNI) and Hd-rR.Y(HNI)rr, demonstrating that a small region on the Y chromosome, which includes DMY, is responsible for the XY sex reversal. Sex-reversed hybrids were only produced in the presence of the Y-chromosomal region derived from the Hd-rR strain, suggesting that missense or regulatory mutations specific to the Hd-rR Y-chromosomal region induce the sex reversal. PMID:19756038

Kato, M; Takehana, Y; Sakaizumi, M; Hamaguchi, S

2010-02-01

164

Rapid communication Male reproductive organs of Apis dorsata  

E-print Network

Rapid communication Male reproductive organs of Apis dorsata G Koeniger M Mardan F Ruttner 1 — Based on an examination of a large number of everted copulatory organs of Apis dor- sata drones. The result is of significance for classification within the genus Apis. Apis dorsata / Apis laboriosa

Paris-Sud XI, Université de

165

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

PubMed

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

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

2008-06-01

166

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

PubMed

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

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

2013-01-01

167

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

PubMed

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

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

2009-12-23

168

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

PubMed Central

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

Nava, Saul S.; Conway, Mirela; Martins, Emilia P.

2009-01-01

169

High-Resolution Sex-Specific Linkage Maps of the Mouse Reveal Polarized Distribution of Crossovers in Male Germline  

PubMed Central

Since the publication of the first comprehensive linkage map for the laboratory mouse, the architecture of recombination as a basic biological process has become amenable to investigation in mammalian model organisms. Here we take advantage of high-density genotyping and the unique pedigree structure of the incipient Collaborative Cross to investigate the roles of sex and genetic background in mammalian recombination. Our results confirm the observation that map length is longer when measured through female meiosis than through male meiosis, but we find that this difference is modified by genotype at loci on both the X chromosome and the autosomes. In addition, we report a striking concentration of crossovers in the distal ends of autosomes in male meiosis that is absent in female meiosis. The presence of this pattern in both single- and double-recombinant chromosomes, combined with the absence of a corresponding asymmetry in the distribution of double-strand breaks, indicates a regulated sequence of events specific to male meiosis that is anchored by chromosome ends. This pattern is consistent with the timing of chromosome pairing and evolutionary constraints on male recombination. Finally, we identify large regions of reduced crossover frequency that together encompass 5% of the genome. Many of these “cold regions” are enriched for segmental duplications, suggesting an inverse local correlation between recombination rate and mutation rate for large copy number variants. PMID:24578350

Liu, Eric Yi; Morgan, Andrew P.; Chesler, Elissa J.; Wang, Wei; Churchill, Gary A.; Pardo-Manuel de Villena, Fernando

2014-01-01

170

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

PubMed

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

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

2012-11-01

171

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

PubMed Central

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

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

2013-01-01

172

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

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

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

173

Drug-using male clients of female sex workers who report being paid for sex: HIV/STI, demographic and drug use correlates  

PubMed Central

Background Research has focused on male clients of female sex workers (FSWs) and their risk for HIV/STIs. Yet, it is unclear whether the commercial sex behaviors of these men are limited to paying for sex, or whether they may also be paid for sex themselves. Methods We analyzed interview data and HIV/STI test results from 170 drug-using male clients of FSWs in Tijuana, Mexico, to determine the extent to which these men report being paid for sex and the association with positive HIV/STI results. Results Over one-quarter of men reported having been paid for sex in the past four months. In a multivariate logistic regression model, reporting having been paid for sex was significantly associated with testing positive for any HIV/STI (Adjusted Odds Ratio [AdjOR] 3.53, 95% C.I. 1.33–9.35), being bisexual (AdjOR 15.59, 95% C.I. 4.81–50.53), injection drug use in the past four months (AdjOR 2.65, 95% C.I. 1.16–6.03), and cocaine use in the past four months (AdjOR 2.93, 95% C.I. 1.22–7.01). Conclusions Findings suggest that drug-using male clients of FSWs may be characterized by unique risk profiles that require tailored HIV prevention interventions. PMID:23863514

Wagner, Karla D.; Pitpitan, Eileen V.; Chavarin, Claudia V.; Magis-Rodriguez, Carlos; Patterson, Thomas L.

2013-01-01

174

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

PubMed Central

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

Zuniga, Mario; Zunt, Joseph; Mejia, Carolina; Montano, Silvia; Sanchez, Jorge L.

2011-01-01

175

Self Ratings of Dependency\\/Addiction Regarding Drugs, Sex, Love, and Food: Male and Female College Students  

Microsoft Academic Search

To what degree do addictions to drugs, sex, love, and food correlate with each other? Are there meaningful sex differences in the addictions? To study this, 9,313 college students (3,083 males, 6,230 females) rated 13 items on 0–100 scales for their dependency\\/addiction to the things represented by the items. Results indicated that males reported significantly more addictions than females, but

RUSSELL EISENMAN; M. L. DANTZKER; LEE ELLIS

2004-01-01

176

Value of magnetic resonance imaging in the evaluation of sex-reassignment surgery in male-to-female transsexuals  

Microsoft Academic Search

Background: We investigated the value of magnetic resonance imaging (MRI) in the evaluation of sex-reassignment surgery in male-to-female transsexual patients. Methods: Ten male-to-female transsexual patients who underwent sex-reassignment surgery with inversion of combined penile and scrotal skin flaps for vaginoplasty were examined after surgery with MRI. Turbo spin-echo T2-weighted and spin-echo T1-weighted images were obtained in sagittal, coronal, and axial

M. Cova; E. Mosconi; G. Liguori; S. Bucci; C. Trombetta; E. Belgrano; R. Pozzi-Mucelli

2003-01-01

177

Sex Ratios of Black Crappies Harvested during Spring Fisheries on Two Minnesota Lakes: Are Males in the Majority?  

Microsoft Academic Search

Sex-selective fishing mortality can alter the demographics and life history patterns of fish populations, yet the extent of this mortality is rarely investigated in harvest-oriented recreational fisheries. Potential differences in habitat use between sexes and nest-guarding behavior suggest that male black crappies Pomoxis nigromaculatus could dominate angler harvest during spring fisheries. We examined the potential for male-dominated harvest in spring

Daniel A. Isermann; Douglas W. Schultz; Andrew J. Carlson

2010-01-01

178

Effects of sex steroids on aromatase mRNA expression in the male and female quail brain  

PubMed Central

Castrated male quail display intense male-typical copulatory behavior in response to exogenous testosterone but ovariectomized females do not. The behavior of males is largely mediated by the central aromatization of testosterone into estradiol. The lack of behavioral response in females could result from a lower rate of aromatization. This is probably not the case because although the enzymatic sex difference is clearly present in gonadally intact sexually mature birds, it is not reliably found in gonadectomized birds treated with testosterone, in which the behavioral sex difference is always observed. We previously discovered that the higher aromatase activity in sexually mature males as compared to females is not associated with major differences in aromatase mRNA density. A reverse sex difference (females > males) was even detected in the bed nucleus of the stria terminalis. We analyzed here by in situ hybridization histochemistry the density of aromatase mRNA in gonadectomized male and female quail that were or were not exposed to a steroid profile typical of their sex. Testosterone and ovarian steroids (presumably estradiol) increased aromatase mRNA concentration in males and females respectively but mRNA density was similar in both sexes. A reverse sex difference in aromatase mRNA density (females >males) was detected in the bed nucleus of subjects exposed to sex steroids. Together these data suggest that although the induction of aromatase activity by testosterone corresponds to an increased transcription of the enzyme, the sex difference in enzymatic activity results largely from post-transcriptional controls that remain to be identified. PMID:20951703

Voigt, Cornelia; Ball, Gregory F.; Balthazart, Jacques

2010-01-01

179

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

E-print Network

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

Hofmann, Hans A.

180

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

PubMed

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

Krulewitz, J E; Nash, J E

1980-01-01

181

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

PubMed

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

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

2014-01-01

182

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

PubMed Central

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.

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

2014-01-01

183

Epidemiology of male same-sex behaviour and associated sexual health indicators in low- and middle-income countries: 2003-2007 estimates  

Microsoft Academic Search

Objectives: To conduct a systematic review of published and unpublished data from research and public health information systems on the prevalence of male-to-male sex in the total male population; as well as among men who have sex with men (MSM), data on prevalence of heterosexual activity and heterosexual unions; prevalence of condom use with male and female partners; and prevalence

K Konda; E R Segura; R Lyerla; Carlos F Caceres

2010-01-01

184

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

PubMed Central

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

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

2012-01-01

185

Rapid modulation of gene expression profiles in the telencephalon of male goldfish following exposure to waterborne sex pheromones.  

PubMed

Sex pheromones rapidly affect endocrine physiology and behaviour, but little is known about their effects on gene expression in the neural tissues that mediate olfactory processing. In this study, we exposed male goldfish for 6h to waterborne 17,20?P (4.3 nM) and PGF2? (3 nM), the main pre-ovulatory and post-ovulatory pheromones, respectively. Both treatments elevated milt volume (P=0.001). Microarray analysis of male telencephalon following PGF2? treatment identified 71 unique transcripts that were differentially expressed (q<5%; 67 up, 4 down). Functional annotation of these regulated genes indicates that PGF2? pheromone exposure affects diverse biological processes including nervous system functions, energy metabolism, cholesterol/lipoprotein transport, translational regulation, transcription and chromatin remodelling, protein processing, cytoskeletal organization, and signalling. By using real-time RT-PCR, we further validated three candidate genes, ependymin-II, calmodulin-A and aldolase C, which exhibited 3-5-fold increase in expression following PGF2? exposure. Expression levels of some other genes that are thought to be important for reproduction were also determined using real-time RT-PCR. Expression of sGnRH was increased by PGF2?, but not 17,20?P, whereas cGnRH expression was increased by 17,20?P but not PGF2?. In contrast, both pheromones increase the expression of glutamate (GluR2a, NR2A) and ?-aminobutyric acid (GABAA ?2) receptor subunit mRNAs. Milt release and rapid modulation of neuronal transcription are part of the response of males to female sex pheromones. PMID:23800560

Lado, Wudu E; Zhang, Dapeng; Mennigen, Jan A; Zamora, Jacob M; Popesku, Jason T; Trudeau, Vance L

2013-10-01

186

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

ERIC Educational Resources Information Center

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…

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

2012-01-01

187

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

ERIC Educational Resources Information Center

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)

Edwards, Carla; Hendrix, Rebecca

2001-01-01

188

Sex Differentials in Unemployment Rates in Male-dominated Occupations and Industries during Periods of Economic Downturn.  

ERIC Educational Resources Information Center

A study examined the ways in which cyclical changes in the business cycle affect unemployment rates by sex in male-dominated occupations and industries. Using data from the monthly reports on employment and earnings issued by the U.S. Bureau of Labor Statistics (1969-1982), the report examined employment rates in selected male-dominated and…

Monk-Turner, Elizabeth

189

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

PubMed

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

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

2014-05-01

190

Nucleus Paragigantocellularis Afferents in Male and Female Rats: Organization, Gonadal Steroid Sensitivity, and Activation During Sexual Behavior  

PubMed Central

The central regulation of genital reflexes is poorly understood. The brainstem nucleus paragigantocellularis (nPGi) of rats is a well-established source of tonic inhibition of genital reflexes. However the organization, gonadal steroid sensitivity, and activity of nPGi afferents during sex have not been fully characterized in male and female rats. To delineate the anatomical and physiological organization of nPGi afferents, the retrograde tracer Fluorogold (FG) was injected into the nPGi of sexually experienced male and female rats. Animals engaged in sexual behavior one hour before sacrifice. Cells containing FG, estrogen receptor alpha (ER?), androgen receptor (AR), and the immediate-early gene product Fos were identified immunocytochemically. Retrograde labeling from the nPGi was prominent in the bed nucleus of the stria terminalis, paraventricular nucleus, posterior hypothalamus, precommissural nucleus, deep mesencephalic nucleus, and periaqueductal gray (PAG) of both sexes. Sex differences were observed in the caudal medial preoptic area (MPO), with significantly more FG+ cells observed in males and in the PAG and inferior colliculus where significantly more FG+ cells were observed in females. The majority of regions that contained FG+ cells also contained ER? or AR, indicating sensitivity to gonadal steroids. The proportions of FG+ cells that co-localized with sex-induced Fos was high in the PVN of both sexes, high in the MPO of males, but low in the PAG of both sexes despite the large number of PAG-nPGi output neurons and Fos+ cells in both sexes. The characterization of these afferents will lead to a further understanding of the neural regulation of genital reflexes. PMID:18393295

Normandin, Joseph J.; Murphy, Anne Z.

2010-01-01

191

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

PubMed Central

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

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

2013-01-01

192

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

PubMed

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

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

2014-07-01

193

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

PubMed Central

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

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

2013-01-01

194

Differential effects of cross-sex hormonal treatment on plasma asymmetric dimethylarginine (ADMA) in healthy male-to-female and female-to-male transsexuals  

Microsoft Academic Search

ObjectiveSex hormone administration affects plasma levels of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA). We investigated the effects of cross-sex hormone treatment (CHT) on plasma ADMA concentration in an open-label study in 40 male-to-female (M–F) and 14 female-to-male (F–M) transsexuals.Methods: M–F received (1) cyproterone acetate (CA) 50mg bid (n=10), (2) CA 50mg bid+ethinyl estradiol (EE) 50?g bid (n=15),

Mathijs C. Bunck; Erik J. Giltay; Michaela Diamant; Louis J. Gooren; Tom Teerlink

2009-01-01

195

MDC1 directs chromosome-wide silencing of the sex chromosomes in male germ cells  

PubMed Central

Chromosome-wide inactivation is an epigenetic signature of sex chromosomes. The mechanism by which the chromosome-wide domain is recognized and gene silencing is induced remains unclear. Here we identify an essential mechanism underlying the recognition of the chromosome-wide domain in the male germline. We show that mediator of DNA damage checkpoint 1 (MDC1), a binding partner of phosphorylated histone H2AX (?H2AX), defines the chromosome-wide domain, initiates meiotic sex chromosome inactivation (MSCI), and leads to XY body formation. Importantly, MSCI consists of two genetically separable steps. The first step is the MDC1-independent recognition of the unsynapsed axis by DNA damage response (DDR) factors such as ataxia telangiectasia and Rad3-related (ATR), TOPBP1, and ?H2AX. The second step is the MDC1-dependent chromosome-wide spreading of DDR factors to the entire chromatin. Furthermore, we demonstrate that, in somatic cells, MDC1-dependent amplification of the ?H2AX signal occurs following replicative stress and is associated with transcriptional silencing. We propose that a common DDR pathway underlies both MSCI and the response of somatic cells to replicative stress. These results establish that the DDR pathway centered on MDC1 triggers epigenetic silencing of sex chromosomes in germ cells. PMID:21536735

Ichijima, Yosuke; Ichijima, Misako; Lou, Zhenkun; Nussenzweig, Andre; Camerini-Otero, R. Daniel; Chen, Junjie; Andreassen, Paul R.; Namekawa, Satoshi H.

2011-01-01

196

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

PubMed Central

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

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

197

Male-biased brood sex ratio depresses average phenotypic quality of barn swallow nestlings under experimentally harsh conditions.  

PubMed

Sex allocation strategies are believed to evolve in response to variation in fitness costs and benefits arising from the production of either sex and can be influenced by the differential susceptibility of sons and daughters to environmental conditions. We tested the effects of manipulating brood size and the sex ratio of the nestmates and the effect of sex on the phenotypic quality of individual barn swallow (Hirundo rustica) nestlings. Brood enlargement, which results in harsh rearing conditions, negatively affected the morphology and immunity of the nestlings. However, the negative consequences of brood enlargement were more marked among male than female offspring. In enlarged but not reduced broods, high proportions of male nestmates resulted in lowered individual body mass, body condition and feather growth. Thus, the consequences of a harsh environment on individual nestlings differed between the sexes and depended on the sex ratio among the other nestlings in the brood. The evolution of sex allocation strategies may therefore depend on the sex of individual nestlings but also on an interaction between environment and progeny sex ratio. PMID:18270745

Saino, Nicola; de Ayala, Rosa Mary; Martinelli, Roberta; Boncoraglio, Giuseppe

2008-05-01

198

Major component in male sex pheromone of cereal pestEurygaster integriceps puton (Heteroptera: Scutelleridae) identified as a homosesquiterpenoid.  

PubMed

A homosesquiterpenoid, (4Z,4'E)-4-(1',5'-dimethyl-4'-heptenylidene)-1-methylcyclohexene, has been identified as a major component of the scent emitted by calling males ofEurygaster integriceps. Minor components of the scent included vanillin. TheE. integriceps male homosesquiterpenoid is an addition to the list of sesquiterpenoids identified as components of male attractant sex pheromones in pentatomoid Heteroptera. PMID:24241843

Staddon, B W; Abdollahi, A; Parry, J; Rossiter, M; Knight, D W

1994-10-01

199

Structural vulnerability and access to medical care among migrant street-based male sex workers in Germany.  

PubMed

This article discusses health concerns of migrant street-based male sex workers (SMSW) in Germany, a population that remains underexplored by health and social scientists. It is based on five months of ethnographic research in 2011/2012, including 46 semi-structured interviews with physicians, social workers, health department staff, and SMSW from Romania and Bulgaria. This is supplemented with annual reports by organizations providing assistance to this population in eight cities. The article contributes, first, an analysis of the increase in migrant SMSW as a response to economic opportunities (freedom of movement across European Union borders) and constraints (transitional measures restricting access to the labor market). It seeks to move beyond the myopic association between sex work and HIV to contextualize health risks as resultant of macro-level processes associated with migration. Second, the article contributes a summary of primary health concerns for this population. Especially troubling is their lack of access to regular medical services, reflecting a socio-legal position that often resembles that of unauthorized migrants rather than European Union citizens. PMID:23455375

Castañeda, Heide

2013-05-01

200

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

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…

Dwyer, R. Gregg; Boyd, Mary S.

2009-01-01

201

Organized Aerobic Exercise and Depression in Male County Jail Inmates  

Microsoft Academic Search

Depression in inmates of correctional facilities is well-docu mented. However, the efficacy of any specific, non-pharmacologic intervention for depression in this population was not located in the literature. This study examined the influence of an exercise program on depression in male county jail inmates. Twenty-five subjects from one jail received three hours of organized aerobic exercise weekly for 12 weeks;

M. Kay Libbus; Joseph A. Genovese; Melissa J. Poole

1994-01-01

202

Organized Aerobic Exercise and Depression in Male County Jail Inmates  

Microsoft Academic Search

Depression in inmates of correctional facilities is well-documented. However, the efficacy of any specific, non-pharmacologic intervention for depression in this population was not located in the literature. This study examined the influence of an exercise program on depression in male county jail inmates. Twenty-five subjects from one jail received three hours of organized aerobic exercise weekly for 12 weeks; 20

M. Kay Libbus; Joseph A. Genovese; Melissa J. Poole

1994-01-01

203

Organized Aerobic Exercise and Depression in Male County Jail Inmates  

Microsoft Academic Search

Depression in inmates of correctional facilities is well-documented. However, the efficacy of any specific, non-pharmacologic intervention for depression in this population was not located in the literature. This study examined the influence of an exercise program on depression in male county jail inmates. Twenty-five subjects from one jail received three hours of organized aerobic exercise weekly for 12 weeks; 20

Joseph A. Genovese; M. Kay Libbus; Melissa J. Poole

1995-01-01

204

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

PubMed Central

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

Rekers, George A.; Lovaas, O. Ivar

1974-01-01

205

[Effect of the hereditary characteristics of male blue foxes Alopex lagopus L. on the sex ratio of their offspring].  

PubMed

Family analysis of a commercial population of the blue fox (the Pushkinskoe Breeding Fur Farm, Moscow oblast) with respect to secondary sex ratio has been performed. The offspring of each individual male or female involved in crossing between 1984 and 1988 was analyzed. The study of all families formed by every male and every female has made it possible to determine a group of "outstanding" fathers (23 out of 287 males), whose offspring was predominantly male (62.1% of the offspring were males, versus 53.9% in the total population). The results of subsequent detailed study on the pedigrees of male blue foxes in whose offspring the sex ratio significantly deviates from 1:1 indicate that this character is transmitted from fathers to sons without the deterioration of other commercially valuable characters. It is presumed that the significant deviation of sex ratio from 1:1 in the offspring of some male blue foxes is determined by genetic factors. PMID:15865299

Beketov, S V; Kashtanov, S N

2005-03-01

206

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

PubMed

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

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

2002-05-01

207

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

NASA Astrophysics Data System (ADS)

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.

Aisenberg, Anita; Baruffaldi, Luciana; González, Macarena

2010-01-01

208

Ultrastructural cytochemistry of the sex pheromone glands of Lutzomyia cruzi male sand flies (Diptera: Psychodidae: Phlebotominae).  

PubMed

The sex pheromone glands of Lutzomyia cruzi male sand flies (Diptera: Psychodidae) were analyzed by cytochemical techniques. In adult males, the epithelium at the fourth abdominal tergite is modified into a glandular epithelium, with large columnar gland cells located side by side. The gland cell cytoplasm contains a large number of mitochondria and peroxisomes, the latter with positive (electron-dense) reaction for catalase, a typical peroxisomal enzyme marker. The gland cell cytoplasm also contains a central vacuolated area, with a large number of electron-lucent vacuoles, not limited by a unit membrane. In well-preserved preparations such vacuoles present a homogenous and slightly electron-dense content, typical of lipid droplets. Indeed, incubation of the tergites with imidazole-buffered osmium tetroxide (to detect lipids) resulted in positive reaction in these vacuoles, as well as in between the microvilli of the gland cells. Use of the osmium-potassium iodide (Os-KI) technique allowed to demonstrate the presence of several endoplasmic reticulum (ER) profiles, as expected in secretory cells. Our data suggest that ER, lipid droplets and peroxisomes are involved in the sand fly pheromone biosynthesis. PMID:18089046

Spiegel, Carolina N; Brazil, Reginaldo P; Soares, Maurilio J

2004-10-01

209

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

PubMed

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

McQuate, Grant T

2014-01-01

210

Reproductive success of male bank voles ( Clethrionomys glareolus ): the effect of operational sex ratio and body size  

Microsoft Academic Search

The operational sex ratio (OSR) may influence the intensity of competition for mates and mate choice and is therefore thought\\u000a to be a major factor predicting the intensity and direction of sexual selection. We studied the opportunity for sexual selection,\\u000a i.e., the variance in male reproductive success and the direction and intensity of sexual selection on male body mass in

Ines Klemme; Hannu Ylönen; Jana A. Eccard

2007-01-01

211

Genome-wide analysis of chromatin states reveals distinct mechanisms of sex-dependent gene regulation in male and female mouse liver.  

PubMed

Chromatin state maps were developed to elucidate sex differences in chromatin structure and their impact on sex-differential chromatin accessibility and sex-biased gene expression in mouse liver. Genes in active, inactive, and poised chromatin states exhibited differential responsiveness to ligand-activated nuclear receptors and distinct enrichments for functional gene categories. Sex-biased genes were clustered by chromatin environments and mapped to DNase-hypersensitive sites (DHS) classified by sex bias in chromatin accessibility and enhancer modifications. Results were integrated with genome-wide binding data for five transcription factors implicated in growth hormone-regulated, sex-biased liver gene expression, leading to the following findings. (i) Sex-biased DHS, but not sex-biased genes, are frequently characterized by sex-differential chromatin states, indicating distal regulation. (ii) Trimethylation of histone H3 at K27 (H3K27me3) is a major sex-biased repressive mark at highly female-biased but not at highly male-biased genes. (iii) FOXA factors are associated with sex-dependent chromatin opening at male-biased but not female-biased regulatory sites. (iv) Sex-biased STAT5 binding is enriched at sex-biased DHS marked as active enhancers and preferentially targets sex-biased genes with sex-differences in local chromatin marks. (v) The male-biased repressor BCL6 preferentially targets female-biased genes and regulatory sites in a sex-independent chromatin state. (vi) CUX2, a female-specific repressor of male-biased genes, also activates strongly female-biased genes, in association with loss of H3K27me3 marks. Chromatin states are thus a major determinant of sex-biased chromatin accessibility and gene expression, with FOXA pioneer factors proposed to confer sex-dependent chromatin opening and STAT5, but not BCL6, regulating sex-biased genes by binding to sites in a sex-biased chromatin state. PMID:23836885

Sugathan, Aarathi; Waxman, David J

2013-09-01

212

Facultative sex ratio adjustment in response to male tarsus length in the Varied Tit Parus varius  

Microsoft Academic Search

During the last decade, evidence from a number of studies has suggested systematic devi- ations from a 1 : 1 primary sex ratio in birds, in spite of the fact that birds have chromosomal sex determination systems; the mechanism of sex allocation is not fully understood. How- ever, it still remains uncertain whether adaptive manipulations of primary sex ratio occur,

Noriyuki Yamaguchi; Katsura K. Kawano; Kazuhiro Eguchi; Tetsukazu Yahara

2004-01-01

213

Peer norms and consistent condom use with female sex workers among male clients in Sichuan province, China  

PubMed Central

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

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

2010-01-01

214

Regret after Sex Reassignment Surgery in a Male-to-Female Transsexual: A Long-Term Follow-Up  

Microsoft Academic Search

This case report describes a four-decade presentation of a non-homosexual gender dysphoric male patient. The case material was collected from two main sources. One of the authors had weekly therapy sessions with the patient over a period of 2 years almost 15 years after sex reassignment surgery. Information was also gained from the patient's medical records covering the period from

Stig-Eric Olsson; Anders Möller

2006-01-01

215

Plasma sex steroid profiles and the seasonal reproductive cycle in male and female winter flounder, Pleuronectes americanus  

Microsoft Academic Search

The pattern of seasonal gonadal development and variations in plasma sex steroids were investigated in adult male and female winter flounder, Pleuronectes americanus (Walbaum), from Conception Bay Newfoundland beginning August 1987 to December 1988. The winter flounder reproductive cycle can be divided into five consecutive phases of relative reproductive activity including: (1) rapid gonadal recrudescence in the fall (August–December); (2)

S. A. Harmin; L. W. Crim; M. D. Wiegand

1995-01-01

216

Perception of self and others in male sex offenders against children: Schema content and its relation to criminal sexual behaviour  

Microsoft Academic Search

Thirty-four civilly committed male sex offenders against children (SOs) chose from a list of traits to describe self, mother, father, best friend, past lover, victim and therapist. Cluster analysis (INDCLAS) uncovered five patterns (i.e. schemas) in Sos’ social perception data: “sexual lover” (past lover described as sexual, arousing, etc. as well as anxious, lonely and worried), “benevolent parent” (mother and

Warren A. Reich; Uri Amit; Harold I. Siegel

2009-01-01

217

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

ERIC Educational Resources Information Center

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…

Ecuyer-Dab, Isabelle; Robert, Michele

2004-01-01

218

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

PubMed Central

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

Goldenberg, Tamar; Clarke, Donato; Stephenson, Rob

2014-01-01

219

Mating System of the European Hornet Vespa crabro : Male Seeking Strategies and Evidence for the Involvement of a Sex Pheromone  

Microsoft Academic Search

We describe details of the mate finding strategy of drones of the European hornet, Vespa crabro, and present evidence for the involvement of sex pheromones. Tests were carried out with free flying drones in natural habitats. Males patrolled the nest site itself, as well as nearby nonresource-based sites, without showing territorial behavior. Patrolling was restricted to sunny spots in the

S. Spiewok; E. Schmolz; J. Ruther

2006-01-01

220

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

Microsoft Academic Search

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

S. SIVARADJAM

221

Sex pheromone and plant-associated odour processing in antennal lobe interneurons of male Spodoptera littoralis (Lepidoptera: Noctuidae)  

Microsoft Academic Search

Antennal lobe interneurons of male Spodoptera littoralis (Boisd.) were investigated by using intracellular recording and staining techniques. Physiological and morphological characteristics of local interneurons and projection neurons responding to sex pheromone and plant-associated volatiles are described. The interneurons identified were divided into three groups, depending on their physiological response characteristics. Both types of interneurons, local interneurons and projection neurons, were

S. Anton; B. S. Hansson

1995-01-01

222

Male orientation to trail sex pheromones in parasitoid wasps: does the spatial distribution of virgin females matter?  

Microsoft Academic Search

We studied male locomotory response to trails and patches of sex pheromone (left respectively by free-ranging females and females constrained to stay on a small area) in the two parasitoids Aphelinus asychis (Hymenoptera: Aphelinidae) and Trichogramma brassicae (Hymenoptera: Trichogrammatidae). Under the hypothesis that the spatial distribution of virgin females differs between these species (scattered among host plants in A. asychis,

Xavier Fauvergue; Pierre Fouillet; Antonio L. M. Mesquita; Michel Boulétreau

1998-01-01

223

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

ERIC Educational Resources Information Center

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…

Regan, Rotrease; Morisky, Donald E.

2013-01-01

224

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

PubMed Central

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

Owens, Ian P F

2002-01-01

225

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

PubMed Central

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

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

2013-01-01

226

Psychological Androgyny, Sex-Typing, and Sex-Role Ideology as Predictors of Male-Female Interpersonal Attraction.  

ERIC Educational Resources Information Center

Studies on college students' ideal dating partners found that: (1) excluding masculine typed females, masculine, feminine, or androgynous subjects desired trait complementarity; and (2) traditional males preferred feminine types, egalitarian males preferred androgynous or feminine types equally, and traditional and egalitarian females preferred…

Orlofsky, Jacob L.

1982-01-01

227

The effects of bisphenol A on sex hormone levels of F0 female rats and F1 male rats during weaning period  

Microsoft Academic Search

The effects of bisphenol A (BPA) were examined on sex hormones of F1 generation male rats during weaning period. Female rats were exposed to BPA from day 0 after pregnancy to the weaning period at doses of 50, 100, or 200 mg kg. The sex hormone levels of F1 generation male rats were determined. This study shows that F0 generation

Bo Lü; Ping Zhan

2010-01-01

228

Plasma sex hormone concentrations during the reproductive cycle in the male lizard, Podarcis s. sicula.  

PubMed

Progesterone, 17-hydroxyprogesterone, androstenedione, 5 alpha-dihydrotestosterone, dehydroepiandrosterone, testosterone and oestradiol concentrations in the plasma were measured by simultaneous radioimmunoassay in males of the lizard Podarcis s. sicula. Hormonal determinations were performed at monthly intervals from January to December (except for August). Testosterone and androstenedione reached peak values of 174.8 ng/ml and 21.4 ng/ml in the mating season (spring) and then testosterone fell abruptly to 5.9 ng/ml in June remaining at this level during hibernation when dehydroepiandrosterone (DHA) reached a maximal level of 28.5 +/- 9.3 ng/ml. Castration resulted in a marked decrease of testosterone, androstenedione, dihydrotestosterone and DHA values, with DHA being significantly lowered only during the winter season. In castrated animals, however, testosterone and androstenedione persisted conspicuously in the plasma during the breeding period, suggesting that adrenal sex steroid output may change during the annual reproductive cycle. In intact animals, progesterone and oestradiol exhibited peak values during the refractory period after the mating season. We suggest a probable role of oestradiol in the induction of the refractory period in this lizard. PMID:2147447

Andò, S; Panno, M L; Ciarcia, G; Imbrogno, E; Buffone, M; Beraldi, E; Sisci, D; Angelini, F; Botte, V

1990-11-01

229

Venue-based affiliation networks and HIV risk-taking behavior among male sex workers  

PubMed Central

Background This study examined venue-based networks constituted by affiliation with gay bars and street intersections where male sex workers (MSWs) congregate to find their sexual/drug-sharing partners, and network influence on risky sexual behavior (e.g., unprotected anal intercourse [UAI]) and HIV infection. Methods Data collected during 2003–2004 in Houston, Texas, consists of 208 MSWs affiliated with 15 gay bars and 51 street intersections. Two-mode network analysis was conducted to examine structural characteristics in affiliation networks, as well as venue-based network influence on UAI and HIV infection. Results Centralized affiliation patterns were found where only a few venues were popular among MSWs and these were highly inter-dependent. Distinctive structural patterns of venue-based clustering were associated with UAI and infection. Individuals who shared venue affiliation with MSWs who engage in UAI were less likely to have UAI themselves. This suggests a downhill effect, i.e., individuals compensate for their risk of infection by adjusting their own risk-taking behavior, based on their perceptions of their venue affiliates. Conclusions Venue-based HIV/AIDs interventions could be tailored to specific venues so as to target specific clusters that are more likely to engage in risky sexual behavior. PMID:23677019

Fujimoto, Kayo; Williams, Mark L.; Ross, Michael W.

2013-01-01

230

Opposite sex-linked behaviors and homosexual feelings in the predominantly heterosexual male majority  

Microsoft Academic Search

Whether homosexual feelings are distributed categorically or dimensionally remains controversial. In an earlier series of studies, medical students anonymously reported a dimensional distribution of homosexual feelings, the ratio of homosexual to heterosexual feelings in men correlating with opposite sex-linked behaviors in childhood and adolescence, and, in both sexes, with current degree of opposite sex identity. Prevalence of homosexual feelings was

Nathaniel McConaghy; Neil Buhrich; Derrick Silove

1994-01-01

231

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

Microsoft Academic Search

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

Jackie Gilfoyle; Jonathan Wilson; Br Own

1992-01-01

232

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

PubMed

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

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

2014-09-15

233

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

Microsoft Academic Search

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

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

2003-01-01

234

Evidence for suppressant effects of testosterone on sex-typical ethanol intake in male Sprague-Dawley rats.  

PubMed

Previous studies have shown that adult female rats consume more ethanol than adult males. Castration of male rats has been found to increase their ethanol intake and preference to levels significantly elevated above their sham-gonadectomized counterparts and similar to levels observed in females. The purpose of the present experiment was to examine whether testosterone replacement in castrated adult male rats would be sufficient to restore the relatively low levels of ethanol drinking characteristic of intact adult male rats. Males were either gonadectomized and implanted with a testosterone propionate pellet (RPL), gonadectomized and implanted with a placebo pellet (GX), sham-gonadectomized and implanted with a placebo pellet (SH), or were left non-manipulated (NM). Voluntary ethanol intake was measured using a 2h limited-access drinking paradigm, with access to two bottles: one containing water, and the other a sweetened ethanol solution. Hormone replacement was sufficient to return ethanol intake and preference of castrates to levels comparable to both SH and NM control males. Ethanol preference of RPL males was also significantly suppressed compared to GX males by the end of the measurement period, whereas these group comparisons did not reach statistical significance for g/kg ethanol intake. These data suggest that testosterone serves to suppress ethanol preference in male rats, and may contribute to the sex differences in ethanol preference and consumption commonly reported in adult rats. PMID:21726585

Vetter-O'Hagen, Courtney S; Sanders, Kristen W; Spear, Linda P

2011-10-31

235

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

PubMed

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

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

2013-08-01

236

Sex-dependent antipsychotic capacity of 17?-estradiol in the latent inhibition model: a typical antipsychotic drug in both sexes, atypical antipsychotic drug in males.  

PubMed

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

Arad, Michal; Weiner, Ina

2010-10-01

237

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

PubMed Central

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

Chinnathambi, Vijayakumar; Yallampalli, Chandrasekhar; Sathishkumar, Kunju

2013-01-01

238

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

PubMed

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

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

2012-02-01

239

Sex Bias in the Representation of Male and Female Characters in Children's Picture Books  

Microsoft Academic Search

Through content analysis, significant differences were found in the representation of male and female characters in a sample of children's picture books published in the years 1976 through 1987. Male characters outnumbered female characters, were given the majority of central character roles, and were more likely to be the recipients of help. In addition, male characters helped other male characters

Scott M. McDonald

1989-01-01

240

Sex Differences in Student Dominance Behavior in Female and Male Professors' Classrooms.  

ERIC Educational Resources Information Center

Male graduate students exhibited significantly more aggressiveness (interruptive behavior) than female students in both male and female professors' classes, although more male aggressiveness occurred in female professors' classes. Male students were more verbally assertive in female professors' classes only. Among students, aggressiveness was…

Brooks, Virginia R.

1982-01-01

241

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

Microsoft Academic Search

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

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

2010-01-01

242

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

PubMed Central

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

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

2011-01-01

243

Religiosity and determinants of safe sex in Iranian non-medical male students.  

PubMed

This study evaluates the safe sex determinants in college students. In the qualitative section, premarital sex, sex with steady girlfriend and religion's impact were highlighted. In the quantitative part, the relations between the religiosity score and past sexual activity, attitude, norms, and self-efficacy with regard to sexual abstinence were investigated. Students who had a higher religious score were significantly more likely to have high self-efficacy in refusing sex, and their attitudes supported their abstinence. Additionally, these students were more likely never to have had a sexual relationship. Findings suggest that greater religious involvement is a protective factor in high-risk sexual behavior. PMID:19229622

Shirazi, Kambiz Karimzadeh; Morowatisharifabad, Mohammad Ali

2009-03-01

244

Serotonin Enhances Central Olfactory Neuron Responses to Female Sex Pheromone in the Male Sphinx Moth Manduca sexta  

Microsoft Academic Search

In the brain of the sphinx moth Manduca sexta, sex-pheromonal information is processed in a prominent male-specific area of the antennal lobe called the macroglomerular complex (MGC). Whole-cell patch-clamp recordings from identified projection (output) neurons in the MGC have shown that serotonin (5-hydroxytryptamine (5-HT)) increases both the excitability of MGC projection neurons and their responses to stimulation with pheromone. At

Peter Kloppenburg; Donald Ferns; Alison R. Mercer

1999-01-01

245

A prospective study on sexual function and mood in female-to-male transsexuals during testosterone administration and after sex reassignment surgery.  

PubMed

Testosterone administration in female-to-male transsexual subjects aims to develop and maintain the characteristics of the desired sex. Very little data exists on its effects on sexuality of female-to-male transsexuals. The aim of this study was to evaluate sexual function and mood of female-to-male transsexuals from their first visit, throughout testosterone administration and after sex reassignment surgery. Participants were 50 female-to-male transsexual subjects who completed questionnaires assessing sexual parameters and mood. The authors measured reproductive hormones and hematological parameters. The results suggest a positive effect of testosterone treatment on sexual function and mood in female-to-male transsexual subjects. PMID:23470169

Costantino, Antonietta; Cerpolini, Silvia; Alvisi, Stefania; Morselli, Paolo Giovanni; Venturoli, Stefano; Meriggiola, Maria Cristina

2013-01-01

246

Understanding the diversity of male clients of sex workers in China and the implications for HIV prevention programmes.  

PubMed

Male clients of sex workers have been overlooked in China's HIV prevention efforts. This study aims to examine men's practices and attitudes toward extramarital sexual relationships, motivations for visiting female sex workers (FSWs), perceptions of sexually transmitted infection (STI)/HIV risk and risk prevention strategies used. One hundred and eighty-six clients of FSWs with varying socio-economic statuses were interviewed in different sex work settings. Men described no conflict between their role as a client and a responsible family provider. They described social pressure from peers and business partners to visit FSWs, sexual pleasure and companionship as motivators to seek commercial sex. While some men reported no risks associated with visiting FSWs, others identified risks such as being arrested by the police, robbed by gangs and threatening the health of their families by contracting a STI. This study underscores the diversity of FSW clients and the need to understand the beliefs and behaviours of different client types to develop appropriate HIV prevention programmes. It also demonstrates the feasibility of recruiting different types of male clients, a hard-to-reach population for Chinese HIV prevention efforts. PMID:22313090

Huang, Yingying; Maman, Suzanne; Pan, Suiming

2012-01-01

247

Reproductive biology of two dominant prairie grasses (Andropogon gerardii and Sorghastrum nutans, Poaceae): male-biased sex allocation in wind-pollinated plants?  

PubMed

It has been proposed that some wind-pollinated plants have the necessary conditions for an optimal sex allocation that is male biased, though there are few data that address this prediction. We determined that two prairie grass species (Andropogon gerardii and Sorghastrum nutans) had reproductive characteristics that theoretically would result in a male-biased allocation: both species were self-incompatible and neither species had increased seed set after supplemental hand pollination. The relative allocation to pollen and seed production was measured in terms of biomass, energy, nitrogen, phosphorus, potassium, magnesium, and calcium. Sex allocation in A. gerardii was significantly male biased (from 60 to 89% male) when measured in currencies of biomass, energy, potassium, and calcium; there was no significant bias in the sex allocation (from 49 to 57% male) when measured in currencies of nitrogen, phosphorus, and magnesium. Sex allocation in S. nutans was significantly male biased (from 69 to 81% male) for all currencies except phosphorus (61% male). This is the first evidence for male-biased sex allocation in any plant or animal hermaphrodite. Though the necessary conditions may be uncommon, male-biased allocation may be found in other species with similar reproductive biology. PMID:21684961

McKone, M; Lund, C; O'Brien, J

1998-06-01

248

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

PubMed

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

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

2013-10-23

249

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

PubMed Central

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

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

2013-01-01

250

Identification of sex pheromone components of darksided cutworm, Euxoa messoria , and modification of sex attractant blend for adult males  

Microsoft Academic Search

Eleven “pheromone-like” compounds were identified in excised abdomen tip extracts of calling adult females of darksided cutworm,Euxoa messoria (Harris). The essential pheromone components were (Z)-7- and (Z)-11-hexadecenyl acetates in a ratio of 1:40, which agreed with an attractant blend developed empirically by field testing the attractancies of synthetic blends. The pheromone component, (Z)-11-hexadecenol, improved the attraction of darksided cutworm males

D. L. Struble; J. R. Byers

1987-01-01

251

AIDS/other STIs prevention in China: the effect of sex worker migration and the organization of the sex industry.  

PubMed

HIV/AIDS prevention projects that pay special attention to the socio-cultural context of a community have been implemented in a number of Asian and African countries recently. Such projects integrate scientific approaches, such as condom promotion, with cultural approaches that focus on regional social norms. This paper explores effective intervention strategies in the context of sex workers' mobility patterns, and the sex industry's internal organization in China. It argues that a social network based on quasi-familial relations and regional ties recruits young women into the business, helps them move vertically as well as horizontally within the business, and facilitates the smooth operation of the business. A sound understanding of the specific characteristics of sex work in China, therefore, is instrumental in formulating effective intervention tactics. PMID:23514622

Zhuang, Kongshao; McQuaide, Shiling

2013-04-01

252

Identification of sex pheromone components of darksided cutworm,Euxoa messoria, and modification of sex attractant blend for adult males.  

PubMed

Eleven "pheromone-like" compounds were identified in excised abdomen tip extracts of calling adult females of darksided cutworm,Euxoa messoria (Harris). The essential pheromone components were (Z)-7- and (Z)-11-hexadecenyl acetates in a ratio of 1?40, which agreed with an attractant blend developed empirically by field testing the attractancies of synthetic blends. The pheromone component, (Z)-11-hexadecenol, improved the attraction of darksided cutworm males whereas the components (Z)-9-tetradecenyl acetate and (Z)-7-dodecenyl acetate inhibited their attraction. The other "pheromone-like" compounds identified in the female extracts had no obvious effect on the attraction of darksided cutworm males. Three compounds that functioned as parapheromones when substituted for (Z)-7-hexadecenyl acetate in the two-component blend were (Z)-7-pentadecenyl, (Z)-7-tetradecenyl, and (Z)-7-tridecenyl acetates. (Z)-11-hexadecenal was not detected in the female extracts, but it had a synergistic effect on the attraction of darksided cutworm moths and inhibited the attraction of male moths of a nontarget species,Helotropha reniformis (Grote). As a trap bait for monitoring purposes, we recommend a four-component blend of (Z)-7-hexadecenyl acetate, (Z)-11-hexadecenyl acetate, (Z)-11-hexadecenol, and (Z)-11-hexadecenal at 12.5, 500, 1, and 10 ?g/red rubber septum dispenser containing 5 ?g of antioxidant 2,6-tert-butyl-4-methyl phenol. This blend is effective under field conditions for at least six weeks. PMID:24302142

Struble, D L; Byers, J R

1987-05-01

253

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

E-print Network

Neonatal testosterone partially organizes sex differences in stress-induced emotionality in mice Testosterone Unpredictable chronic mild stress Sex difference Development Major depressive disorder (MDD-established technique used in the field of sexual differentiation (neonatal injection with testosterone) to masculinize

Sibille, Etienne

254

Street Life and Drug Risk Behaviors Associated with Exchanging Sex Among Male Street Children in Lahore, Pakistan  

PubMed Central

Background Throughout the developing world, children living on urban streets is a byproduct of economic deprivation. In Lahore, Pakistan, there are an estimated 5,000–7,000 street children. Purpose The study examined HIV risk behaviors and factors associated with exchanging sex among male street children in Lahore, Pakistan. Methods The survey was conducted from August 2003 to March 2004 among 565 registrants, ages 5–19, of Project Smile, a program that aimed to enhance the lives of street children in Lahore. We analyzed the frequency of and correlates of recent (past three months) sex exchange for money, drugs, or goods. Multivariate log-binomial regression was used to evaluate the independent effect of covariates on exchange sex. Results Approximately 40% of participants reported having exchanged sex during the past three months. In multivariate analysis, the factors associated with exchanging sex were living on the street for longer than 48 months (Prevalence Ratio [PR]=1.36, 95% Confidence Interval [CI]: 0.99–1.85), reporting ever having used drugs (PR=1.87, 1.10–3.16), cutting one’s self (PR=1.66, 95% CI: 1.26–2.19), and having heard of HIV/AIDS (PR=1.36, 95% CI: 1.03–1.80) after adjusting for demographic and street life variables. Conclusions We found high rates of sex exchange among a sample of street children in Lahore, Pakistan. The finding that children who have heard about HIV/AIDS are more likely to exchange sex suggests that children at HIV risk talk about HIV, but accuracy of their conversations is unclear. Street children in Pakistan are in great need of HIV education and safe alternatives for generating income. PMID:19237107

Towe, Vivian L.; Hasan, Salman ul; Zafar, S. Tariq; Sherman, Susan G.

2009-01-01

255

Sex differences in response to nonconspecific advertisement calls: receiver permissiveness in male and female tungara frogs  

E-print Network

aggressive calls in response to two other heterospecific/ancestral calls. The responses of males wereGregor & Dabelsteen 1996; Searcy & Now- icki 2000; Gerhardt & Huber 2002). For example, male crickets, frogs and birds

Ryan, Michael J.

256

Function of the male-gamete-specific fusion protein HAP2 in a seven-sexed ciliate.  

PubMed

HAP2, a male-gamete-specific protein conserved across vast evolutionary distances, has garnered considerable attention as a potential membrane fusogen required for fertilization in taxa ranging from protozoa and green algae to flowering plants and invertebrate animals [1-6]. However, its presence in Tetrahymena thermophila, a ciliated protozoan with seven sexes or mating types that bypasses the production of male gametes, raises interesting questions regarding the evolutionary origins of gamete-specific functions in sexually dimorphic species. Here we show that HAP2 is expressed in all seven mating types of T. thermophila and that fertility is only blocked when the gene is deleted from both cells of a mating pair. HAP2 deletion strains of complementary mating types can recognize one another and form pairs; however, pair stability is compromised and membrane pore formation at the nuclear exchange junction is blocked. The absence of pore formation is consistent with previous studies suggesting a role for HAP2 in gamete fusion in other systems. We propose a model in which each of the several hundred membrane pores established at the conjugation junction of mating Tetrahymena represents the equivalent of a male/female interface, and that pore formation is driven on both sides of the junction by the presence of HAP2. Such a model supports the idea that many of the disparate functions of sperm and egg were shared by the "isogametes" of early eukaryotes and became partitioned to either male or female sex cells later in evolution. PMID:25155508

Cole, Eric S; Cassidy-Hanley, Donna; Fricke Pinello, Jennifer; Zeng, Hong; Hsueh, Marion; Kolbin, Daniel; Ozzello, Courtney; Giddings, Thomas; Winey, Mark; Clark, Theodore G

2014-09-22

257

Sex Differences in Processing Speed: Developmental Effects in Males and Females  

ERIC Educational Resources Information Center

The purpose of this study was to compare the cognitive abilities and selected achievement performance of females and males across the lifespan on standardization samples of broad cognitive abilities in 1987 participants (1102 females, 885 males) from the WJ III, 4253 participants (2014 males, 2239 females) from the WJ-R, and 4225 participants…

Camarata, Stephen; Woodcock, Richard

2006-01-01

258

Increased reproductive effort results in male-biased offspring sex ratio: an experimental study in a species with reversed sexual size dimorphism.  

PubMed Central

Adaptive sex-ratio theory predicts that parents should overproduce the more beneficial offspring sex. Based on a recent experimental study of lesser black-backed gulls, we tested this hypothesis with the great skua, Catharacta skua, a bird species closely related to gulls but where females are the larger sex. When in poor body condition, the gulls overproduced daughters, the smaller and more viable sex under those circumstances. To discriminate between a mandatory physiological overproduction of female (i.e. non-male) eggs versus the overproduction of the smaller and presumably more viable sex, we conducted an egg-removal experiment with the great skua. Since the males are smaller, larger size and being male are separated. Through egg removal we induced females to increase egg production effort. Eggs were sexed using a DNA-based technique. Manipulated pairs produced a significant male bias at the end of the extended laying sequence, while the sex ratio in the control group did not differ from unity. Our results present an example of facultative sex-ratio manipulation and support the hypothesis that in sexually dimorphic birds parents overproduce the smaller sex under adverse conditions. PMID:11600083

Kalmbach, E.; Nager, R. G.; Griffiths, R.; Furness, R. W.

2001-01-01

259

Prevalence of HIV, Herpes Simplex Virus-2, and Syphilis in male sex partners of pregnant women in Peru  

PubMed Central

Background: Sexually active heterosexual men may represent an important risk factor for HIV infection and STI transmission to their female partners and unborn children, though little is known about the prevalence of STIs in this population. We sought to determine the prevalence of HIV, herpes simplex virus type 2 (HSV-2), and syphilis infection and associated risk behaviors among male sex partners of pregnant women in Peru. Methods: Survey and seroprevalence data were collected from 1,835 male partners of pregnant women in four cities in Peru. Serum was tested for antibodies to HIV, HSV-2, and syphilis. Results: Among the 1,835 male participants, HIV prevalence was 0.8% (95% CI = 0.5–1.4%), HSV-2 16.0% (95% CI = 14.3–17.8%), and syphilis 1.6% (95% CI = 1.0–2.2%). Additionally, 11.0% reported a lifetime history of intercourse with men, and 37.1% with female sex workers. Unprotected intercourse with men during the previous year was reported by 0.9% and with female sex workers by 1.2%. Conclusion: Pregnant women's sex partners reported lifetime sexual contact with core risk groups, had an elevated prevalence of HSV-2, and demonstrated the potential to spread HIV and other STIs to their partners. Though the prevalence of HIV in the population was not significantly higher than observed in other samples of heterosexuals in Peru, the risk of HIV transmission to their female partners may be exacerbated by their increased prevalence of HSV-2 infection. Further study of heterosexual populations is necessary to fully understand the epidemiology of HIV/STIs in Latin America. PMID:18284696

Clark, Jesse L; Konda, Kelika A; Munayco, Cesar V; Pun, Monica; Lescano, Andres G; Leon, Segundo R; Pajuelo, Jose; Suarez-Ognio, Luis; Klausner, Jeffrey D; Coates, Thomas J; Caceres, Carlos F

2008-01-01

260

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

PubMed Central

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 significantly different between XYY and XXYY. In all groups, there were significantly more with SRS scores in the severe range compared to the SRS normative sample. All groups scored lowest (better) on Social Motivation. Relationships between SRS scores and demographic and clinical variables were examined. Results describe the social skills in males with SCA, and suggest that an additional Y chromosome may contribute to increased risk of autistic behaviors. PMID:22502852

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

2012-01-01

261

Social deficits in male children and adolescents with sex chromosome aneuploidy: a comparison of XXY, XYY, and XXYY syndromes.  

PubMed

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 significantly different between XYY and XXYY. In all groups, there were significantly more with SRS scores in the severe range compared to the SRS normative sample. All groups scored lowest (better) on Social Motivation. Relationships between SRS scores and demographic and clinical variables were examined. Results describe the social skills in males with SCA, and suggest that an additional Y chromosome may contribute to increased risk of autistic behaviors. PMID:22502852

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

2012-01-01

262

Sex-role reversed nuptial feeding reduces male kleptoparasitism of females in Zeus bugs (Heteroptera; Veliidae).  

PubMed

Males of a variety of taxa occasionally steal food secured by their mates. In some spiders and insects, males rely entirely on this form of intraspecific kleptoparasitism for their subsistence. However, this male strategy may be costly for females and a variety of different female counteradaptations have been proposed. In Zeus bugs (Phoreticovelia spp.), males ride on the back of their mates for extended periods and females produce a gland secretion that males feed on. By experimentally occluding the dorsal glands in females and varying food availability, we show that nuptial feeding by females reduces the extent to which the males kleptoparasitize their mates. We suggest that females have, at least in part, evolved this unique form of nuptial feeding as a counteradaptation to reduce the rate of kleptoparasitism by males. PMID:17148270

Arnqvist, Göran; Jones, Therésa M; Elgar, Mark A

2006-12-22

263

Sex-role reversed nuptial feeding reduces male kleptoparasitism of females in Zeus bugs (Heteroptera; Veliidae)  

PubMed Central

Males of a variety of taxa occasionally steal food secured by their mates. In some spiders and insects, males rely entirely on this form of intraspecific kleptoparasitism for their subsistence. However, this male strategy may be costly for females and a variety of different female counteradaptations have been proposed. In Zeus bugs (Phoreticovelia spp.), males ride on the back of their mates for extended periods and females produce a gland secretion that males feed on. By experimentally occluding the dorsal glands in females and varying food availability, we show that nuptial feeding by females reduces the extent to which the males kleptoparasitize their mates. We suggest that females have, at least in part, evolved this unique form of nuptial feeding as a counteradaptation to reduce the rate of kleptoparasitism by males. PMID:17148270

Arnqvist, Goran; Jones, Theresa M; Elgar, Mark A

2006-01-01

264

Childhood Attachment and Adult Attachment in Incarcerated Adult Male Sex Offenders  

Microsoft Academic Search

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. The combined sex-offender groups reported significantly less secure maternal, paternal, and adult attachment than did the nonoffenders and significantly less secure maternal attachment than did the property offenders. Intrafamilial child molesters were found to have

STEPHEN W. SMALLBONE; MARK R. DADDS

1998-01-01

265

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

PubMed

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

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

2012-03-01

266

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

PubMed Central

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

Harumoto, Toshiyuki; Anbutsu, Hisashi; Fukatsu, Takema

2014-01-01

267

Sex, stress and social status: patterns in fecal testosterone and glucocorticoid metabolites in male Ethiopian wolves.  

PubMed

Ethiopian wolves, Canis simensis, live in large multi-male family packs, where males are philopatric and do not disperse. Within a pack, mating and breeding is largely monopolized by the dominant male and female, although extra-pack copulations are common, and subordinate males may sire pups in neighboring packs. Regardless of paternity, all males in a pack help rear the pups. We non-invasively studied patterns in fecal testosterone and glucocorticoid metabolite concentrations using radioimmunoassays of fecal samples collected from nine wild male Ethiopian wolves between August 2007 and February 2008. We tested the predictions of the Challenge Hypothesis, namely that fecal testosterone metabolite concentrations would be higher during the annual mating season, which is the portion of the reproductive cycle when mating and increased aggression typically occur, and lower when there were pups in the pack for which to care. Contrary to the predictions of the Challenge Hypothesis, we did not detect patterns in fecal testosterone metabolite concentrations associated with reproductive stage during our study period. Similarly, we found no patterns associated with reproductive stage in male fecal glucocorticoid metabolite concentrations. Dominant males had higher average fecal testosterone and glucocorticoid metabolite concentrations than did subordinates, which may be related to higher rates of aggression and mate guarding in dominant males of group-living canids, a pattern also reported in African wild dogs, Lycaon pictus. PMID:22841807

van Kesteren, Freya; Sillero-Zubiri, Claudio; Millar, Robert; Argaw, Kifle; Macdonald, David W; Paris, Monique

2012-10-01

268

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

ERIC Educational Resources Information Center

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

O'Neill, Lisa

2011-01-01

269

Sexually Transmitted Infections among Heterosexual Male Clients of Female Sex Workers in China: A Systematic Review and Meta-Analysis  

PubMed Central

Background Female sex workers have been the target of numerous sexually transmitted infection (STI) prevention strategies in China, but their male clients have attracted considerably less public health attention and resources. We sought to systematically assess the prevalence of HIV, syphilis, gonorrhea, and chlamydia among heterosexual male clients of female sex workers in China. Methods/Principal Findings Original research manuscripts were identified by searching Chinese and English language databases, and 37 studies analyzing 26,552 male clients were included in the review. Client STI prevalence across studies was heterogeneous. Pooled prevalence estimates and 95% confidence intervals were 0.68% (0.36–1.28%) for HIV, 2.91% (2.17–3.89%) for syphilis, 2.16% (1.46–3.17%) for gonorrhea, and 8.01% (4.94–12.72%) for chlamydia. Conclusions/Significance The pooled prevalence estimates of HIV, syphilis, gonorrhea, and chlamydia among clients in this review exceed the prevalences previously reported among population-representative samples and low-risk groups in China. However, heterogeneity across studies and sampling limitations prevent definitive conclusions about how the prevalence of STIs in this population compares to the general population. These findings suggest a need for greater attention to clients’ sexual risk and disease prevalence in China’s STI research agenda in order to inform effective prevention policies. PMID:23951153

McLaughlin, Megan M.; Chow, Eric P. F.; Wang, Cheng; Yang, Li-Gang; Yang, Bin; Huang, Jennifer Z.; Wang, Yanjie; Zhang, Lei; Tucker, Joseph D.

2013-01-01

270

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

PubMed

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

Chan, K L; Mok, C C

2013-11-01

271

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

PubMed Central

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

2012-01-01

272

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

PubMed Central

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

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

2013-01-01

273

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

PubMed

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

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

2013-10-01

274

Aust. J. Zool., 1984, 32, 721-42 Changes in the Male Reproductive Organs of the  

E-print Network

of the gross reproductive anatomy of the male dugong, even the exact location of the testes (Harrison 1969.Accordingly,thispaper alsoincludesdetailsof the gross anatomy and histology of the male reproductive organs. #12;H. Marsh, G. E. Heinsohn Anatomy, University of Queensland, St Lucia, Qld 4067. Abstract The anatomy and histology of the male

Marsh, Helene

275

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

Microsoft Academic Search

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

DeAnn K. Gauthier; Nancy K. Chaudoir

2004-01-01

276

Ablatio penis: Normal male infant sex-reassigned as a girl  

Microsoft Academic Search

Forty-five cases of genetic males were assigned and habilitated as females, 43 because of a congenitally defective penis (micropenis with or without hypospadias), and two because of infantile ablatio penis. One of the latter has an identical twin brother as a control. Now 9 years old, she has differentiated a female gender identity in marked contrast to the male gender

John Money

1975-01-01

277

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

ERIC Educational Resources Information Center

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

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

2013-01-01

278

Effects of Visual Exposure to the Opposite Sex: Cognitive Aspects of Mate Attraction in Human Males  

Microsoft Academic Search

This research is an investigation into the cognitive aspects of mate attraction in human males. Two experiments demonstrate that visual exposure to women (in person or within photo- graphs) can prime large changes in the attitudes, mood states, and personality trait descriptions of male participants. These changes, furthermore, are such that participants show greater conformity to female mate preferences as

James R. Roney

2003-01-01

279

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

PubMed

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

Miller, R L

1995-01-01

280

The Association between the Levels of Serum Ferritin and Sex Hormones in a Large Scale of Chinese Male Population  

PubMed Central

Background The ferritin is an important participant of iron-storage but its regulation and related factors were not well defined. The present objective was to explore the potential association between serum ferritin levels and sex hormones. Methods 1999 Chinese men in the Fangchenggang Area Male Health and Examination Survey (FAMHES) were recruited in this cross-sectional study. Levels of serum ferritin, total testosterone (free testosterone was calculated from the total one), estradiol and sex hormone-binding protein were detected in venous blood samples. The effects of age, BMI, smoking as well as alcohol consumption were analyzed on ferritin levels, respectively, and then the Pearson’s correlation analysis was used to evaluate the association between ferritin levels and sex hormones adjusting for the above factors. Results The age, BMI and alcohol consumption significantly affected serum ferritin levels, but there was no significant difference between smokers and nonsmokers. Ferritin levels were significantly and negatively associated with total testosterone (R?=??0.205, P< 0.001), sex hormone-binding protein (R?=??0.161, P<0.001) and free testosterone (R?=??0.097, P<0.001). After age and alcohol consumption were adjusted, the above associations were still significant (R?=??0.200, ?0.181 and ?0.083, respectively, all P<0.001). However, there was only borderline negative association between ferritin levels and estradiol (adjusted R?=??0.039, P?=?0.083). Conclusion The large scale of epidemic results showed the significantly negative associations between serum ferritin levels and sex hormones, which may provide more clues to explore the potential regulation and biological mechanism of ferritin. PMID:24146788

Zhang, Haiying; Gao, Yong; Tan, Aihua; Zhang, Shijun; Xiao, Qiang; Zhang, Bing; Huang, Lulu; Ye, Bingbing; Qin, Xue; Wu, Chunlei; Lu, Zheng; Zhang, Youjie; Liao, Ming; Yang, Xiaobo; Mo, Zengnan

2013-01-01

281

A Trivers-Willard Effect in Contemporary Humans: Male-Biased Sex Ratios among Billionaires  

PubMed Central

Background Natural selection should favour the ability of mothers to adjust the sex ratio of offspring in relation to the offspring's potential reproductive success. In polygynous species, mothers in good condition would be advantaged by giving birth to more sons. While studies on mammals in general provide support for the hypothesis, studies on humans provide particularly inconsistent results, possibly because the assumptions of the model do not apply. Methodology/Principal Findings Here, we take a subset of humans in very good condition: the Forbe's billionaire list. First, we test if the assumptions of the model apply, and show that mothers leave more grandchildren through their sons than through their daughters. We then show that billionaires have 60% sons, which is significantly different from the general population, consistent with our hypothesis. However, women who themselves are billionaires have fewer sons than women having children with billionaires, suggesting that maternal testosterone does not explain the observed variation. Furthermore, paternal masculinity as indexed by achievement, could not explain the variation, since there was no variation in sex ratio between self-made or inherited billionaires. Conclusions/Significance Humans in the highest economic bracket leave more grandchildren through sons than through daughters. Therefore, adaptive variation in sex ratios is expected, and human mothers in the highest economic bracket do give birth to more sons, suggesting similar sex ratio manipulation as seen in other mammals. PMID:19142225

Cameron, Elissa Z.; Dalerum, Fredrik

2009-01-01

282

A Trivers-Willard Effect in Contemporary Humans: Male-Biased Sex Ratios among Billionaires  

Microsoft Academic Search

BackgroundNatural selection should favour the ability of mothers to adjust the sex ratio of offspring in relation to the offspring's potential reproductive success. In polygynous species, mothers in good condition would be advantaged by giving birth to more sons. While studies on mammals in general provide support for the hypothesis, studies on humans provide particularly inconsistent results, possibly because the

Elissa Z. Cameron; Fredrik Dalerum; David Reby

2009-01-01

283

Male and female morbidity in general practice: The nature of sex differences  

Microsoft Academic Search

Outcomes from large scale health surveys suggest women's morbidity and medical care utilization to be higher than men's. Survey findings have often been questioned on methodological grounds, a main criticism being the subjective nature of the data on which the alleged sex differences are based. Moreover, health differences vary with the type of illness (behavior) that is assessed. Instead of

Cecile M. T. Gijsbers van Wijk; Annemarie M. Kolk; Wil J. H. M. van Den Bosch

1992-01-01

284

Minority Stress in Same-Sex Male Relationships: When Does It Impact Relationship Satisfaction?  

Microsoft Academic Search

The minority stress model (Meyer, 2003) has been proposed to explain higher rates of psychopathology in lesbian, gay, and bisexual individuals. However, studies of minority stress have rarely taken into account the interface between minority stress and same-sex relationship processes. In the current study, 142 gay men in romantic relationships completed an online survey assessing minority stress constructs, relationship features,

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

2011-01-01

285

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

ERIC Educational Resources Information Center

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…

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

2006-01-01

286

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

NASA Astrophysics Data System (ADS)

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

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

2001-09-01

287

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

PubMed

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

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

2005-10-01

288

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

PubMed Central

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

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

2013-01-01

289

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

PubMed

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

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

2014-12-01

290

Sex, Lies, and Video Games: The Portrayal of Male and Female Characters on Video Game Covers  

Microsoft Academic Search

Two hundred twenty-five console video game covers obtained from online retail sites were examined for portrayals of men and\\u000a women. We hypothesized that males would be portrayed more often, but that females would be portrayed in a more hyper-sexualized\\u000a manner. Male characters were almost four times more frequently portrayed than female characters and were given significantly\\u000a more game relevant action.

Melinda C. R. Burgess; Steven Paul Stermer; Stephen R. Burgess

2007-01-01

291

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

PubMed

Because consistent condom use is an effective strategy in the prevention of sexually transmitted infections and HIV transmission, it is important to examine social cognitive influences of consistent condom use not only among female sex workers (FSWs) but also among their male clients, for whom less is known. Because little is known about how HIV knowledge and condom attitudes affect condom use among male clients of FSWs in the Philippines, the main objective was to determine what characteristics (age, education, HIV knowledge, marital status) as well as attributes taken from protection motivation theory (perceived vulnerability, perceived severity, response efficacy) are significantly associated with consistent condom use among male clients of FSWs. Logistic regression analyses showed that the odds of using condoms consistently with an FSW are 13% higher for those with more years of education (adjusted odds ratio [AOR] = 1.13; 95% confidence interval [CI] = 1.03, 1.23), higher versus lower perception of severity of HIV/AIDS (AOR = 1.97; 95% CI = 1.04, 3.73), and had a higher score for response efficacy of condoms (AOR = 1.14; 95% CI = 1.03, 1.27). Future HIV/AIDS prevention interventions that address condom use among male clients should promote educational attainment and focus on awareness of the enduring negative health consequences of acquiring HIV/AIDS, as well as cultivate positive attitudes toward the efficacy of condom use, using creative social marketing strategies. PMID:22773598

Regan, Rotrease; Morisky, Donald E

2013-04-01

292

[Pattern of plasma sex steroid hormone levels during the breeding season of male and female skink: Eumeces chinensis].  

PubMed

Changes in gonadal activity and plasma sex steroid hormone levels in male and female Eumece chinensis during the breeding season were described. The results showed that: The vitellogensis of follicles of female Eumeces chinensis needed the stimulation of 17beta-estradiol (E2). As ovary masses reached peak values between late April and mid-May, E2 levels rose to the top value by late March, and then sharply declined but went up again before preovulation; The physiological functions of plasma progesterone (P) consisted in its oviductal egg retention, embryo development, and eggshell formation. P levels fluctuated near the basic value between mid-March and late April. In mid-May, with the onset of ovulation, plasma P levels rose rapidly, reached peak value by late May and declined sharply after ovulation. Plasma E2 levels declined as plasma P levels rose, showing an inverse relationship between them; In males, plasma Testosterone (T) levels were closely correlated with the maintenance of spermatogenesis activities, male and male combat, sexual display, and mating. Plasma T levels tended to rise after the termination of hibernation, and reached peak value by mid-April. After mid-May, with the testis aggressing, plasma T levels gradually went down and reached bottom value by late June. PMID:15789762

Hu, Jian Rao; Du, Ji Zeng; Ji, Xiang

2004-12-01

293

Sex-specific survival rates of adult roseate terns: are males paying a higher reproductive cost than females?  

USGS Publications Warehouse

A long-term mark-recapture/resighting program has been carried out on the Roseate Terns (Sterna dougallii) nesting at Falkner Island, Connecticut, USA from the late 1980s through the mid 2000s, and from 1995-1998 an intensive collaborative study of food-provisioning of chicks by their parents also was conducted on many of the banded individuals at this site. Adult female Roseate Terns have significantly higher 'local survival' rates than do males. While both sexes feed their young, males usually have higher prey delivery rates than do females and do most feeding of the (oldest if more than one) chick just before it fledges. Males usually depart at the same time as the (oldest) fledgling, while successful females parents may linger at the colony site for up to two weeks. The lower 'local survival' rate of males probably does not represent lower colony-site fidelity, but instead may reflect the price they pay for doing more 'child care,' especially if fledglings are still dependant on them for food during post breeding dispersal and (at least early) migration.

Spendelow, J.A.; Shealer, D.A.; Hatfield, J.S.; Nichols, J.D.; Nisbet, I.C.T.

2005-01-01

294

Effect of sex and dietary organic zinc on growth performance, carcass traits, tissue mineral content, and blood parameters of broiler chickens.  

PubMed

Zinc (Zn) is an essential mineral for animal development and function. A study was carried out to evaluate the effect of sex and dietary organic zinc (OZ) on growth performance, carcass traits, tissue mineral content, and blood parameters of broiler chickens. A total of 240 1-day-old male and 240 female broiler chicks (Cobb × Cobb) were assigned to two dietary levels of OZ (2 × 2 factorial) with six replicates per treatment (20 birds/replicate pen). The OZ supplementation levels were 0 and 25 ppm. Results showed that OZ supplementation did not affect the growth performance of male and female broilers, but the males showed significantly better (P < 0.05) growth performance than females did. Similarly, OZ supplementation did not affect the thickness of both the back and thigh skin of male and female broilers; however, males had thicker skin than females. Dietary OZ supplementation did not affect collagen contents in the skin and meat samples. Male broilers had higher skin collagen contents than females, but no sex difference was found in meat collagen contents. OZ supplementation did not affect the shear force values of skin and meat samples. Male broilers had higher shear force values of back skin than females, but not in the meat samples. Dietary OZ supplementation increased (P < 0.05) the thigh meat Zn content in both sexes. The plasma Ca content was significantly (P < 0.05) increased by dietary OZ supplementation; however, other blood parameters were not affected by dietary OZ supplementation. Males had higher plasma glucose and cholesterol content than females. It is concluded that dietary OZ supplementation at the level of 25 ppm does not affect the growth performance and skin quality of broiler chickens but increases the Zn content in thigh meat and Ca content in plasma of broiler chickens. Male broilers had better growth performance and skin quality than females. PMID:22167309

Salim, H M; Lee, H R; Jo, C; Lee, S K; Lee, Bong Duk

2012-06-01

295

Male reproductive patterns in nonhibernating bats  

Microsoft Academic Search

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

P. H. Krutzsch

296

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

PubMed Central

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

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

2003-01-01

297

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

NSDL National Science Digital Library

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

2008-10-06

298

Contextual influences on safer sex negotiation among female sex workers (FSWs) in Hong Kong: the role of non-governmental organizations (NGOs), FSWs' managers, and clients  

Microsoft Academic Search

Despite social-cognitive interventions to increase safer sex awareness, condom use among female sex workers (FSWs) continued to be inconsistent. To account for the possible influences of contextual factors that may hinder or promote FSWs' safer sex negotiation and condom use, the present study examined the effects of non-governmental organizations (NGOs), FSWs' managers, and clients on FSWs' negotiation efficacy and condom-use

Shannon S. Y. Cheng; Winnie W. S. Mak

2010-01-01

299

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

PubMed Central

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

Valentova, Jaroslava Varella; Stulp, Gert; Trebicky, Vit; Havlicek, Jan

2014-01-01

300

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

PubMed

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

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

2014-07-01

301

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

PubMed

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

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

2008-03-01

302

Analysis of Male Pheromones That Accelerate Female Reproductive Organ Development  

PubMed Central

Male odors can influence a female's reproductive physiology. In the mouse, the odor of male urine results in an early onset of female puberty. Several volatile and protein pheromones have previously been reported to each account for this bioactivity. Here we bioassay inbred BALB/cJ females to study pheromone-accelerated uterine growth, a developmental hallmark of puberty. We evaluate the response of wild-type and mutant mice lacking a specialized sensory transduction channel, TrpC2, and find TrpC2 function to be necessary for pheromone-mediated uterine growth. We analyze the relative effectiveness of pheromones previously identified to accelerate puberty through direct bioassay and find none to significantly accelerate uterine growth in BALB/cJ females. Complementary to this analysis, we have devised a strategy of partial purification of the uterine growth bioactivity from male urine and applied it to purify bioactivity from three different laboratory strains. The biochemical characteristics of the active fraction of all three strains are inconsistent with that of previously known pheromones. When directly analyzed, we are unable to detect previously known pheromones in urine fractions that generate uterine growth. Our analysis indicates that pheromones emitted by males to advance female puberty remain to be identified. PMID:21347429

Flanagan, Kelly A.; Webb, William; Stowers, Lisa

2011-01-01

303

The role of female and male sex hormones in the healing process of preexisting lingual and gastric ulcerations.  

PubMed

Studies in different animal species and in humans have suggested that sex hormones influence gastric acid secretion and contribute to the integrity of the oral and gastroduodenal mucosa but the effect of male and female sex hormones on the healing of the preexisting ulcers in the oral cavity and stomach have not been studied. We compared the effects of major male hormone, testosterone, and female hormone, progesterone, on the healing of lingual and gastric ulcers induced by acetic acid technique in male rats with intact or removed testicles (testectomy) and female rats with intact or removed ovaries (ovariectomy). The gastric acid secretion was determined in rats with gastric ulcers equipped with chronic gastric fistula (GF). Rats were sacrificed at day 7 upon ulcer induction; the ulcer area was measured by planimetry and the lingual and gastric blood flow (GBF) was determined by H(2)-gas clearance method and venous blood was collected for determination of plasma gastrin and plasma proinflammatory cytokine interleukin (IL)-1 beta levels. Gastric acid output from GF rats was significantly reduced while plasma gastrin was significantly enhanced in testectomized animals as compared to those in intact control rats and these effects were reversed by supplementation of testectomized animals with testosterone. The area of lingual and gastric ulcers in placebo-control rats decreased significantly at day 7 and this effect was significantly accelerated by testectomy or ovariectomy. In contrast, testosterone significantly delayed ulcer healing while producing a significant fall in the gastric blood flow and lingual blood flow determined at the margin of these ulcers. Treatment with progesterone significantly accelerated ulcer healing and increased the gastric and lingual blood flow at margin of these ulcers. Testosterone applied alone or supplemented in testectomized animals produced the significant increment in plasma IL-1 beta levels as compared to the respective levels of this cytokine in placebo-control animals. We conclude that: 1) major male (testosterone) and female (progesterone) sex hormones exhibit opposite effect on healing of preexisting ulcers in the oral cavity and stomach because testosterone markedly delayed while progesterone significantly accelerated this healing; 2) testosterone-induced delay in ulcer healing involves the fall in the gastric microcirculation at the margin of lingual and gastric ulcers and the excessive production and release of proinflammatory cytokine IL-1 beta; and 3) testectomy improves the gastric ulcer healing due to inhibition of gastric acid secretion and the rise in plasma gastrin, which exerts gastroprotective, trophic and ulcer healing action on the gastric mucosa. PMID:15608364

Machowska, A; Szlachcic, A; Pawlik, M; Brzozowski, T; Konturek, S J; Pawlik, W W

2004-07-01

304

Studies on the Sex-Specific Lethals of DROSOPHILA MELANOGASTER. V. Sex Transformation Caused by Interactions between a Female-Specific Lethal, Sxlf#1, and the Male-Specific Lethals mle(3)132, msl-227, and mle  

PubMed Central

Interactions between a female-specific lethal mutant, Sxlf#1, and each of three male-specific lethal mutants, mle(3)132, msl-227 and mle, of Drosophila melanogaster were observed to produce morphological changes in various sexually dimorphic external characters. Chromosomal females heterozygous for Sxlf#1 and homozygous for any one of the male-specific lethals (and to a lesser degree heterozygous for male-specific lethals) sometimes had sex combs, male-type tergites, male-type sternites, male-type anal plates or male-type external genitalia. Penetrance was not high and expression was often incomplete; single individuals never had all the sexually dimorphic structures transformed. When mothers were homozygous for male-specific lethals, higher proportions of female progeny were affected than when mothers were heterozygous, suggesting a maternal effect. PMID:6818105

Uenoyama, T.; Fukunaga, A.; Ioshi, K.

1982-01-01

305

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

PubMed Central

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

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

2013-01-01

306

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

PubMed Central

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

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

2010-01-01

307

Autoradiographic localization of sex steroid hormones in the lymphatic organs of baboons  

Microsoft Academic Search

The localization of radiolabeled estradiol and dihydrotestosterone was examined in the lymphatic organs of both male and female baboons. A total of 12 baboons were divided into two groups, each containing three males and three females. Each animal in one group, both males and females, was injected intravenously with 1 µg\\/kg body weight of 3H-estradiol while those in the second

Frank J. Weaker; Peter J. Sheridan

1983-01-01

308

Sex pheromones of rice moth,Corcyra cephalonica Stainton : I. Identification of male pheromone.  

PubMed

Behavioral observations of the rice moth (Corcyra cephalonica, Pyralidae, Galleriinae) in the laboratory have shown that a male wing-gland pheromone induces attraction of female moths. This pheromone was identified as a blend of (E,E) and (Z,E)-farnesal. Wing-gland extracts or synthetic compounds were shown to be attractive to females by inducing walking. PMID:24302327

Zagatti, P; Kunesch, G; Ramiandrasoa, F; Malosse, C; Hall, D R; Lester, R; Nesbitt, B F

1987-07-01

309

The Gendered Stereotype of the ?Good Manager? Sex Role Expectations towards Male and Female Managers  

Microsoft Academic Search

In the past 30 years, U.S. and international studies have shown that societal expectations of the ?good manager? are closely related to the male stereotype. However, it is not clear, whether this stereotype is the same for men and women alike in managerial positions. The results of a German study with 625 students and 376 professionals participating between 1997 and

Markus Gmuer

2006-01-01

310

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

ERIC Educational Resources Information Center

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

Goldman, Sylvie

2013-01-01

311

Males' and females' conversational behavior in cross-sex dyads: From gender differences to gender similarities  

Microsoft Academic Search

We investigated gender differences in conversational behavior in an experimental setting. Twenty men and 20 women were randomly paired in 20 dyads and were asked to discuss a given topic. We examined the transcripts through a varied range of behavioral variables. First we analyzed the sequential ordering of utterances in order to establish the way male and female speakers take

Agnesa Pillon; Catherine Degauquier; François Duquesne

1992-01-01

312

The Stigmatized Woman: The Professional Woman in a Male Sex-Typed Career.  

ERIC Educational Resources Information Center

Applies Erving Goffman's stigma theory to impressions of 25 women in educational administration careers. Analyzes data from an earlier study to show how women administrators, confronted with male leadership norms, deviate, acquire stigma, and become marginal. Concludes with suggestions for change, citing 32 references. (MLH)

Marshall, Catherine

1985-01-01

313

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

PubMed Central

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

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

2009-01-01

314

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

USGS Publications Warehouse

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

Donham, R. S.

1979-01-01

315

Male reproductive organs are at risk from environmental hazards.  

PubMed

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

Bonde, Jens Peter

2010-03-01

316

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

USGS Publications Warehouse

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

Mech, L.D.

1980-01-01

317

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

PubMed

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

Gow, Elizabeth A; Wiebe, Karen L

2014-05-01

318

Left hemisphere and male sex dominance of cerebral hemiatrophy (Dyke–Davidoff–Masson Syndrome)  

Microsoft Academic Search

Although radiological findings of cerebral hemiatrophy (Dyke–Davidoff–Masson Syndrome) are well known, there is no systematic study about the gender and the affected side in this syndrome. Brain images in 26 patients (mean aged 11) with cerebral hemiatrophy were retrospectively reviewed. Nineteen patients (73.5%) were male and seven patients (26.5%) were female. Left hemisphere involvement was seen in 18 patients (69.2%)

Özkan Ünal; Temel Tombul; Bayram Ç?rak; Ömer Anlar; Lütfi ?ncesu; Mustafa Kayan

2004-01-01

319

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

PubMed

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

Quero, C; Camps, F; Guerrero, A

1995-12-01

320

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

PubMed

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

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

2009-09-01

321

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

NASA Astrophysics Data System (ADS)

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

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

2012-03-01

322

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

E-print Network

; Parzefall et al., 1980; Guillaume, 2002). For instance, in the cave salamander Proteus anguinus, a slowly.g. ampullary organs in cave cat shes (Weber, 1995) or cave am- phibians (Proteus: Istenic & Bulog, 1984

Schlupp, Ingo

323

Quantitative variation in ecological and hormonal variables correlates with spatial organization of pronghorn ( Antilocapra americana ) males  

Microsoft Academic Search

Whereas variation in pronghorn (Antilocapra americana) spatial organization is well documented, underlying ecological or physiological explanations are not well understood. This\\u000a study quantitatively describes spacing systems of pronghorn males and correlates of their spatial organization. I collected\\u000a behavioral data from two populations in South Dakota (Wind Cave) and Montana (Bar Diamond) to determine if males differed\\u000a in space use, response

C. R. Maher

2000-01-01

324

Cold acclimation in Peromyscus: individual variation and sex effects in maximum and daily metabolism, organ mass and body composition.  

PubMed

We studied metabolic and organ mass responses to thermal acclimation (7 weeks at 5 degrees C or 23 degrees C) in deer mice, Peromyscus maniculatus. Cold acclimation resulted in significantly higher maximal oxygen consumption in thermogenesis (V(O(2)max)) and daily mean oxygen consumption (V(O(2)mean)), an increase in the mass of most visceral organs, a lower absolute body fat and a marginally significant increase in hematocrit. The mass of digestive organs and body fat content differed significantly between sexes. Acclimation effects on fat content were more pronounced in females. Variation in heart and lung mass was positively correlated with V(O(2)max) and V(O(2)mean), while body fat content was negatively correlated with both traits. Nonetheless, a large fraction of the metabolic difference between cold- and warm-acclimated groups remained unexplained. Associations between traits at lower levels of biological organization measured here and whole-organism energetics remained consistent across acclimation temperatures, except for the correlation between kidney mass and V(O(2)mean), which was positive and significant in cold acclimation and negligible following warm acclimation. We conclude that: (1) V(O(2)max) and V(O(2)mean) share a common physiological basis that remains overall the same across acclimation regimes; (2) changes in these traits are associated primarily with changes in heart mass; and (3) male and female deer mice respond differently to thermal acclimation, possibly due to differences in reproductive allocation. PMID:19684213

Rezende, Enrico L; Hammond, Kimberly A; Chappell, Mark A

2009-09-01

325

Does it Matter How You Ask? Question Wording and Males' Reporting of Contraceptive Use at Last Sex1  

PubMed Central

This paper reports results from a unique experiment conducted in the 2002 National Survey of Family Growth (NSFG) to gauge the effect of question format on men’s reports of contraceptive use at last sexual intercourse. Respondents received separate questions about their own and their partners’ contraceptive use or one combined question about either partner’s contraceptive use. We examine whether receiving separate questions, as opposed to one combined question, is related to higher reports of using any contraceptive method, specific methods, female methods in addition to male methods, and the number of methods reported. We find that reports of any contraceptive use at last sex and use of the most common methods, condoms and the pill, were stable across question formats. However, we find significantly higher reports of withdrawal, combining male and female methods, and multiple method use among men who received the separate-question format. We also find that characteristics of the sexual experience in question condition the effect of question format on men’s reports. PMID:23017915

Yarger, Jennifer; Abma, Joyce

2012-01-01

326

Organization of Needs in Male and Female Drug and Alcohol Users  

ERIC Educational Resources Information Center

The Personality Research Form (PRF) was administered to 1,095 college students. Students were divided into groups of nonusers of drugs and alcohol and users of a variety of drug combinations. Results suggest organization of motivational tendencies is the same for both sexes and for different types of substance users. (Author)

Huba, George J.; And Others

1977-01-01

327

Reproductive Biology of Two Dominant Prairie Grasses (Andropogon gerardii and Sorghastrum nutans, Poaceae): Male-Biased Sex Allocation in Wind-Pollinated Plants?  

Microsoft Academic Search

It has been proposed that some wind-pollinated plants have the necessary conditions for an optimal sex allocation that is male biased, though there are few data that address this prediction. We determined that two prairie grass species ( Andropogon gerardii and Sorghastrum nutans) had reproductive characteristics that theoretically would result in a male-biased allocation: both species were self-incompatible and neither

Mark J. McKone; Christopher P. Lund; Joshua M. O'Brien

1998-01-01

328

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

PubMed Central

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

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

1997-01-01

329

Structure of Vomeronasal Organ (Jacobson organ) in Male Camelus Domesticus Var. dromedaris persica.  

PubMed

The vomeronasal organ (VNO) is a tubular structure in the roof of nasal cavity. The important role of this organ is olfaction of sexual odour. In this study, position, anatomical structure and histology of VNO in Iranian camels (camelus domesticus var. dromedaris persica) were determined. Fourteen healthy male camel heads were collected from an industrial slaughterhouse in Tehran, Iran, for anatomical and histological studies (seven each). The length of VNO and width of dental pad and the number and width of palatine crests were measured. For anatomical studies, the mandible was removed, and maxilla and nasal cavity was cut longitudinally and transversely. For histological studies, the mandible was removed, and first 0.5 cm of initial part of VNO was cut. Then, nasal cavity was cut in some segments with 2 cm thickness. The width of VNO was 3.85 ± 0.31 cm and 1.57 ± 0.18 cm in front and distal parts, respectively. The length of VNO was 15.61 ± 0.59 cm. In histological examinations, VNO was surrounded by J-shape hyaline cartilage. The lining epithelium of lateral wall of VNO was originated from respiratory epithelium, while it had an olfactory epithelium origin in the medial wall. Lamina propria and tunica submucosa were a cavernous connective tissue with seromucous gland with abundant of serous secretory units. The lumen of VNO opens into nasal cavity. The presence of olfactory epithelium found in our study indicates an important role for VNO in pheromone perception and beginning of sexual behaviour. PMID:24611976

Karimi, H; Mansoori Ale Hashem, R; Ardalani, G; Sadrkhanloo, R; Hayatgheibi, H

2014-12-01

330

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

PubMed Central

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

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

2014-01-01

331

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

PubMed Central

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

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

2014-01-01

332

Sex, contraception and childbearing among high-risk youth: do different factors influence males and females?  

PubMed

The correlates of high-risk adolescent sexual behaviors were investigated through use of data from the 1979-92 waves of the US National Longitudinal Survey of Youth and the linked 1994 young adult data file on their children. The sample was comprised of 959 youth, most of whom were 14-18 years old at the time of the 1994 survey, who were the oldest child of the original female respondents. The analysis of risk behaviors was restricted to the 483 youth known to be sexually active. Compared to their non-sexually-active counterparts, sexually active youth had lower family incomes, mothers with lower educational attainment, and mothers who themselves became sexually active at a young age (mean, 15.5 years). Sexual activity at an early age was further associated with substance abuse, a view of oneself as a risk taker, and a history of running away from home. Early age at first coitus, nonuse of contraception, and adolescent childbearing were significantly linked with depression, feeling like a failure, and little sense of control over one's life in female respondents. In contrast, sexually active teen males reported low levels of depression and felt in control of their lives. After parenthood, tentative evidence of maturity emerged for both genders. Young mothers reduced their alcohol consumption and spent less time with peers who drank; young fathers exhibited lower levels of willingness to take risks, higher depression, and greater involvement in socially productive activities. PMID:9711453

Kowaleski-Jones, L; Mott, F L

1998-01-01

333

Testosterone regulation of sex steroid-related mRNAs and dopamine-related mRNAs in adolescent male rat substantia nigra  

PubMed Central

Background Increased risk of schizophrenia in adolescent males indicates that a link between the development of dopamine-related psychopathology and testosterone-driven brain changes may exist. However, contradictions as to whether testosterone increases or decreases dopamine neurotransmission are found and most studies address this in adult animals. Testosterone-dependent actions in neurons are direct via activation of androgen receptors (AR) or indirect by conversion to 17?-estradiol and activation of estrogen receptors (ER). How midbrain dopamine neurons respond to sex steroids depends on the presence of sex steroid receptor(s) and the level of steroid conversion enzymes (aromatase and 5?-reductase). We investigated whether gonadectomy and sex steroid replacement could influence dopamine levels by changing tyrosine hydroxylase (TH) protein and mRNA and/or dopamine breakdown enzyme mRNA levels [catechol-O-methyl transferase (COMT) and monoamine oxygenase (MAO) A and B] in the adolescent male rat substantia nigra. We hypothesized that adolescent testosterone would regulate sex steroid signaling through regulation of ER and AR mRNAs and through modulation of aromatase and 5?-reductase mRNA levels. Results We find ER? and AR in midbrain dopamine neurons in adolescent male rats, indicating that dopamine neurons are poised to respond to circulating sex steroids. We report that androgens (T and DHT) increase TH protein and increase COMT, MAOA and MAOB mRNAs in the adolescent male rat substantia nigra. We report that all three sex steroids increase AR mRNA. Differential action on ER pathways, with ER? mRNA down-regulation and ER? mRNA up-regulation by testosterone was found. 5? reductase-1 mRNA was increased by AR activation, and aromatase mRNA was decreased by gonadectomy. Conclusions We conclude that increased testosterone at adolescence can shift the balance of sex steroid signaling to favor androgenic responses through promoting conversion of T to DHT and increasing AR mRNA. Further, testosterone may increase local dopamine synthesis and metabolism, thereby changing dopamine regulation within the substantia nigra. We show that testosterone action through both AR and ERs modulates synthesis of sex steroid receptor by altering AR and ER mRNA levels in normal adolescent male substantia nigra. Increased sex steroids in the brain at adolescence may alter substantia nigra dopamine pathways, increasing vulnerability for the development of psychopathology. PMID:22867132

2012-01-01

334

A Content-Analysis of Selected Picture Books Examining the Portrayal of Sex-Roles and Representation of Males and Females.  

ERIC Educational Resources Information Center

This study examines the portrayal of sex-roles and the representation of males and females in selected preschool level picture books. The analyses include 125 picture books representing the work of 100 authors, randomly selected from a collection of approximately 1,000 picture books available in the children's department of the Mishawaka, Indiana…

La Dow, Stephanie

335

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

ERIC Educational Resources Information Center

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

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

2005-01-01

336

Sex steroids deficiency impairs glucose transporter 4 expression and its translocation through defective Akt phosphorylation in target tissues of adult male rat  

Microsoft Academic Search

There is a substantial body of evidence suggesting that altered level of sex steroids in male is associated with insulin resistance and type 2 diabetes mellitus. However, the mechanism of this effect is not apparent. Our recent study indicated that testosterone deprivation decreases insulin receptor expression and glucose oxidation in insulin target tissues. The present study was designed to assess

Thirupathi Muthusamy; Palaniappan Murugesan; Karundevi Balasubramanian

2009-01-01

337

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

PubMed Central

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

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

2000-01-01

338

The role of male-male relationships in partner violence treatment groups: the effects of improving same sex relationships on attachment  

E-print Network

with partner abusers, due to the unique environment that is created where males interact with and establish relationships with other males. This male-male socialization may have potential positive effects on the course and outcome of therapy. This study sought...

Barnes, Ashley D.

2009-05-15

339

Sex, dependency, and helping  

Microsoft Academic Search

Examined whether the difference in the helping behavior of males and females is due to the sex of the person giving help or the sex of the person receiving it. In an experiment with 52 male and 52 female undergraduates, dependency, sex of potential helper, and sex of dependent person were all varied factorially. An interaction of dependency and sex

Charles L. Gruder; Thomas D. Cook

1971-01-01

340

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

PubMed

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

Weiss, Bernard

2011-10-01

341

Variation in sex allocation and male-female trade-offs in six populations of Collinsia parviflora (Scrophulariaceae s.l.).  

PubMed

Assumed trade-offs between male and female functions in hermaphroditic flowers have been difficult to demonstrate. Collinsia parviflora (Scrophulariaceae) is a winter annual that exhibits significant among-population variation in corolla size in British Columbia, Canada. We asked whether reduction in secondary male allocation (i.e., the attractive corolla), a preliminary indicator of mating system, was matched by a reduction in primary male allocation (i.e., pollen production), and whether there were allocation trade-offs between male and female function both within and among six study populations. Larger-flowered populations allocated more to male function (androecium and corolla biomass), and because populations did not vary in female biomass allocation (gynoecium and calyx), population differences were not due to simple allometric scaling. Populations also differed in per-flower gamete production (pollen and ovules). We found male-female trade-offs within populations between androecium and gynoecium mass and between corolla and calyx mass. Among populations, there was a marginal trade-off between pollen and ovule production and a significant within-male trade-off between pollen grain size and number. Trade-offs between the sexes were primarily apparent when we controlled for flower size in the analysis. Variation among populations in sex allocation may reflect different optima related to the mating system. PMID:21653477

Parachnowitsch, Amy L; Elle, Elizabeth

2004-08-01

342

Sex-Role Stereotyping and Male-Female Character Distribution in Popular, Prestigious, and Sex-Role Defining Children's Literature from 1959 to 1972.  

ERIC Educational Resources Information Center

This dissertation explored the extent and kind of sex-role stereotyping in popular, prestigious, and sex-role defining children's picture books printed between 1959 and 1972. The sample consisted of two categories of popular children's picture books, best-selling golden books and "New York Times" children's best-sellers, one category of Caldecott…

Fraad, Harriet

343

Sex Differences in Lopinavir (LPV) and Ritonavir (RTV) Pharmacokinetics (PKs) Among HIV-infected Females and Males  

PubMed Central

Objectives We compared the pharmacokinetics of lopinavir (LPV) and ritonavir (RTV) between female and males. Methods This two-step, multicenter, pharmacokinetic study enrolled HIV-infected adults on lopinavir/ritonavir (LPV/r) capsules (400/100mg BID) plus 1 or more NRTIs. All subjects underwent 12 hour pharmacokinetic sampling. The PK sampling was repeated in subjects receiving the LPV/r tablet formulation. Results Step 1 enrolled 37 women and 40 men; step 2 included 42 subjects from step 1 plus 35 new participants (39 women and 38 men). LPV pharmacokinetics in females and males were not significantly different with either formulation. Females had significantly higher median RTV AUC0–12h with both the soft gel capsule and tablet formulations (SGC:5395 vs. 4119 ng*hr/ml, p=0.026; tablet 5310 vs. 3941 ng*hr/ml, p=0.012), higher median Cmax (SGC:802 vs. 635 ng/mL, p=0.032; tablet: 773 vs. 570 ng/ml, p=0.006)) and lower median CL/F (SGC:18.54 vs. 24.31 L/hour, p=0.026; tablet: 18.83 vs. 25.37 L/hour, p=0.012). RTV CL/F was slower in females after weight adjustment with both formulations. Conclusion The pharmacokinetics of LPV in the SGC and tablet formulations are comparable in HIV infected subjects. Females had higher RTV AUC0–12h and lower CL/F with both formulations. The mechanism of the sex difference in RTV CL/F warrants elucidation. PMID:21233301

Umeh, OC; Currier, JS; Park, JG; Cramer, Y; Hermes, AE; Fletcher, CV

2012-01-01

344

Expression and function of the Drosophila melanogaster ADH in male Ceratitis capitata adults: a potential strategy for medfly genetic sexing based on gene-transfer technology.  

PubMed

The aim of development of a Mediterranean fruit fly Ceratitis capitata genetic sexing strain derives from the large scale SIT programmes being carried out to control this pest. Toward this direction, we present here the male-specific expression of the Drosophila melanogaster alcohol dehydrogenase (ADH) in medfly transgenic adults generated by Minos-mediated germ line transformation. This expression pattern is obtained by using a promoter fragment of the male-specific gene MSSP-alpha2 of the medfly. We show that the heterologous enzyme is functional in the medfly oxidizing both ethanol and 2-propanol. Although leading to an approximately twofold increase of total ADH activity in male compared to female transgenic adults, these expression levels are not enough for performing genetic sexing when high doses of environmental alcohol are applied. This could be achieved either by further enhancement of the transgene expression or by generating an Adh- line to host the Minos insertions. PMID:11437916

Christophides, G K; Savakis, C; Mintzas, A C; Komitopoulou, K

2001-06-01

345

Cognitive effects of variations in pubertal timing: is puberty a period of brain organization for human sex-typed cognition?  

PubMed

There is considerable interest in the organizational effects of pubertal sex hormones on human sex-related characteristics. Recent evidence from rodents suggests that there is a decreasing window of sensitivity to sex hormones throughout adolescence. If adolescence also represents a period of brain organization in human beings, then the timing of exposure to sex-typical hormones at puberty should have long-term effects on sex-typed characteristics: individuals with early timing should be more sex-typed than individuals with late timing. We tested this hypothesis in 320 young adults by relating their pubertal timing (retrospective comparison to peers) to cognitive abilities that show sex differences. Results provide partial support for the hypothesis. For men, pubertal timing was inversely related to scores on a test of three-dimensional mental rotations. Effects do not appear to be due to duration of hormone exposure (time since puberty), but other potential influences need further study. PMID:23603479

Beltz, Adriene M; Berenbaum, Sheri A

2013-05-01

346

Do Male and Female Cowbirds See Their World Differently? Implications for Sex Differences in the Sensory System of an Avian Brood Parasite  

PubMed Central

Background Male and female avian brood parasites are subject to different selection pressures: males compete for mates but do not provide parental care or territories and only females locate hosts to lay eggs. This sex difference may affect brain architecture in some avian brood parasites, but relatively little is known about their sensory systems and behaviors used to obtain sensory information. Our goal was to study the visual resolution and visual information gathering behavior (i.e., scanning) of brown-headed cowbirds. Methodology/Principal Findings We measured the density of single cone photoreceptors, associated with chromatic vision, and double cone photoreceptors, associated with motion detection and achromatic vision. We also measured head movement rates, as indicators of visual information gathering behavior, when exposed to an object. We found that females had significantly lower density of single and double cones than males around the fovea and in the periphery of the retina. Additionally, females had significantly higher head-movement rates than males. Conclusions Overall, we suggest that female cowbirds have lower chromatic and achromatic visual resolution than males (without sex differences in visual contrast perception). Females might compensate for the lower visual resolution by gazing alternatively with both foveae in quicker succession than males, increasing their head movement rates. However, other physiological factors may have influenced the behavioral differences observed. Our results bring up relevant questions about the sensory basis of sex differences in behavior. One possibility is that female and male cowbirds differentially allocate costly sensory resources, as a recent study found that females actually have greater auditory resolution than males. PMID:23544049

Fernandez-Juricic, Esteban; Ojeda, Agustin; Deisher, Marcella; Burry, Brianna; Baumhardt, Patrice; Stark, Amy; Elmore, Amanda G.; Ensminger, Amanda L.

2013-01-01

347

Radiological evaluation by magnetic resonance of the 'new anatomy' of transsexual patients undergoing male to female sex reassignment surgery.  

PubMed

Magnetic resonance (MR) is the best way to assess the new anatomy of the pelvis after male to female (MtF) sex reassignment surgery. The aim of the study was to evaluate the radiological appearance of the small pelvis after MtF surgery and to compare it with the normal women's anatomy. Fifteen patients who underwent MtF surgery were subjected to pelvic MR at least 6 months after surgery. The anthropometric parameters of the small pelvis were measured and compared with those of ten healthy women (control group). Our personal technique (creation of the mons Veneris under the pubic skin) was performed in all patients. In patients who underwent MtF surgery, the mean neovaginal depth was slightly superior than in women (P=0.009). The length of the inferior pelvic aperture and of the inlet of pelvis was higher in the control group (P<0.005). The inclination between the axis of the neovagina and the inferior pelvis aperture, the thickness of the mons Veneris and the thickness of the rectovaginal septum were comparable between the two study groups. MR consents a detailed assessment of the new pelvic anatomy after MtF surgery. The anthropometric parameters measured in our patients were comparable with those of women. PMID:22673584

Brunocilla, E; Soli, M; Franceschelli, A; Schiavina, R; Borghesi, M; Gentile, G; Pultrone, C V; Martorana, G; Orrei, M G; Colombo, F

2012-09-01

348

Personal or relational? Examining sexual health in the context of HIV serodiscordant same-sex male couples  

PubMed Central

Couples’ ability to adopt a “we” orientation has been associated with optimal health outcomes. This study examined how personal and relational motivations are uniquely associated with unprotected anal intercourse (UAI), protected anal intercourse (PAI), and the absence of sexual activity within HIV-serodiscordant same-sex male couples. HIV-positive men and their HIV-negative partners (n = 116 couples, 232 men) completed questionnaires and HIV-positive men had blood drawn for viral load. Results of a multinomial logistic regression illustrated that sexual satisfaction was positively associated with PAI among HIV-negative partners and negatively associated with PAI among HIV-positive partners. Endorsing a “we” orientation was positively associated with PAI among HIV-positive partners. Findings suggest that HIV-positive partners who espouse a “we” orientation may be willing to forgo their personal interests to protect their HIV-negative partners from HIV transmission. Couples-based interventions are warranted to help strengthen relationship dynamics to enhance the sexual health of serodiscordant couples. PMID:23636681

Gamarel, K.E.; Starks, T.J; Dilworth, S.E.; Neilands, T.B.; Taylor, J.M.; Johnson, M.O.

2014-01-01

349

Personal or relational? Examining sexual health in the context of HIV serodiscordant same-sex male couples.  

PubMed

Couples' ability to adopt a "we" orientation has been associated with optimal health outcomes. This study examined how personal and relational motivations are uniquely associated with unprotected anal intercourse (UAI), protected anal intercourse (PAI), and the absence of sexual activity within HIV-serodiscordant same-sex male couples. HIV-positive men and their HIV-negative partners (N = 116 couples, 232 men) completed questionnaires and HIV-positive men had blood drawn for viral load. Results of a multinomial logistic regression illustrated that sexual satisfaction was positively associated with PAI among HIV-negative partners and negatively associated with PAI among HIV-positive partners. Endorsing a "we" orientation was positively associated with PAI among HIV-positive partners. Findings suggest that HIV-positive partners who espouse a "we" orientation may be willing to forgo their personal interests to protect their HIV-negative partners from HIV transmission. Couples-based interventions are warranted to help strengthen relationship dynamics to enhance the sexual health of serodiscordant couples. PMID:23636681

Gamarel, Kristi E; Starks, T J; Dilworth, S E; Neilands, T B; Taylor, J M; Johnson, M O

2014-01-01

350

The Earliest Case of Extreme Sexual Display with Exaggerated Male Organs by Two Middle Jurassic Mecopterans  

PubMed Central

Background Many extant male animals exhibit exaggerated body parts for display, defense or offence in sexual selection, such as male birds of paradise showing off colorful and elegant feathers and male moose and reindeers bearing large structured antlers. For insects, male rhinoceros and stag beetles have huge horn-like structure for fighting and competition and some male Leptopanorpa scorpionflies have very long abdominal terminal segments for sexual display and competition. Fossil records of insects having exaggerated body parts for sexual display are fairly rare. One example is two male holcorpids with elongate abdominal segments from sixth (A6) to eighth (A8) and enlarged male genitalia from Eocene, suggesting evolution of these characters occurred fairly late. Principal Findings We document two mecopterans with exaggerated male body parts from the late Middle Jurassic Jiulongshan Formation in northeastern China. Both have extremely extended abdominal segments from A6 to A8 and enlarged genitalia, which might have been used for sexual display and, to less extent, for fighting with other males in the competition for mates. Although Fortiholcorpa paradoxa gen. et sp. nov. and Miriholcorpa forcipata gen. et sp. nov. seem to have affinities with Holcorpidae, we deem both as Family Incertae sedis mainly due to significant differences in branching pattern of Media (M) veins and relative length of A8 for F. paradoxa, and indiscernible preservation of 5-branched M veins in hind wing for M. forcipata. Conclusions/Significance These two new taxa have extended the records of exaggerated male body parts of mecopterans for sexual display and/or selection from the Early Eocene to the late Middle Jurassic. The similar character present in some Leptopanorpa of Panorpidae suggests that the sexual display and/or sexual selection due to extremely elongated male abdominal and sexual organs outweigh the negative impact of bulky body and poor mobility in the evolutionary process. PMID:23977031

Wang, Qi; Shih, Chungkun; Ren, Dong

2013-01-01

351

Estrogen receptor-alpha distribution in male rodents is associated with social organization.  

PubMed

It has been hypothesized that site-specific reduction of estrogen receptor-alpha (ERalpha) is associated with the expression of male prosocial behaviors. Specifically, highly social males are predicted to express significantly lower levels of ERalpha than females and less social males in brain regions associated with prosocial behavior including the bed nucleus of the stria terminalis (BST) and the medial amygdala (MeA). This hypothesis was tested by comparing ERalpha immunoreactivity (IR) in three species of microtines, the polygynous montane (Microtus montanus) and meadow (M. pennsylvanicus) voles and the monogamous pine vole (M. pinetorum), and two species of cricetines that differ in the extent of social pair-bond formation, Siberian (Phodopus sungorus) and Djungarian (P. campbelli) hamsters. As predicted, ERalpha-IR was sexually dimorphic in the BST and MeA of the highly social species, with females expressing more ERalpha-IR cells than males. Male and female montane voles did not differ. Male and female meadow voles differed in the ventromedial hypothalamus, with females expressing more ERalpha-IR cells. Male pine voles expressed lower levels of ERalpha-IR in the MeA than male montane and meadow voles and in the BST relative to montane males. Male Djungarian hamsters, which show higher levels of parental care, had fewer ERalpha-IR cells in the BST than male Siberian hamsters. Results indicate that the distribution of ERalpha differs relative to the continuum of species-typical affiliative behavior and supports the hypothesis that ERalpha has a significant role in regulating species-specific social organization. PMID:16374794

Cushing, Bruce S; Wynne-Edwards, Katherine E

2006-02-01

352

Sex Workers, Fem Queens, and Cross-Dressers: Differential Marginalizations and HIV Vulnerabilities Among Three Ethnocultural Male-to-Female Transgender Communities in New York City  

PubMed Central

This article describes 3 distinct ethnocultural male-to-female transgender communities in New York City: the low-income African American/Black1 and Latina(o) House Ball community; low-income, often undocumented immigrant Asian sex workers; and middle-class White cross-dressers. These communities are highly socially isolated from each other and are more connected to their ethnocultural contexts than to an abstract and shared transgender identity. Whereas previous research either has viewed male-to-female transgender people as one monolithic group or has separated them into abstract racial categories unconnected to their communities and lifestyles, this article positions them within specific social networks, cultures, neighborhoods, and lifestyles. With regard to HIV vulnerabilities, violence, and rape, House Ball community members seemed to engage in the riskiest form of survival sex work, whereas Asian sex workers seemed to engage in moderate-risk survival sex work. White cross-dressers seemed to engage in very low-risk recreational sex work.2 PMID:19079558

Hwahng, Sel Julian; Nuttbrock, Larry

2008-01-01

353

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

PubMed Central

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

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

2011-01-01

354

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

E-print Network

Effects of steroid sex hormones on chick embryo gonads in organ culture, with special reference to hormonal control of gonadal sex differentiation J. JORDANOV Pavlina ANGELOVA lnstitute of Morpho, cultured in media containing no hormones, was close to that of gonads of equivalent age in ovo

Paris-Sud XI, Université de

355

Climate influences fledgling sex ratio and sex-specific dispersal in a seabird.  

PubMed

Climate influences the dynamics of natural populations by direct effects over habitat quality but also modulating the phenotypic responses of organisms' life-history traits. These responses may be different in males and females, particularly in dimorphic species, due to sex-specific requirements or constraints. Here, in a coastal seabird, the European shag (Phalacrocorax aristotelis), we studied the influence of climate (North Atlantic Oscillation, NAO; Sea Surface Temperature, SST) on two sex-related population parameters: fledgling sex ratio and sex-specific dispersal. We found that fledgling sex ratio was female skewed in NAO-positive years and male skewed in NAO-negative years. Accordingly, females dispersed a longer distance in NAO-positive years when females were overproduced, and on the contrary, males dispersed more in NAO-negative years. Overall, our findings provide rare evidence on vertebrates with genetic sex determination that climate conditions may govern population dynamics by affecting sex-specific density and dispersal. PMID:23951144

Barros, Alvaro; Alvarez, David; Velando, Alberto

2013-01-01

356

Effects of perinatal loratadine exposure on male rat reproductive organ development.  

PubMed

Normal pre- and postnatal male reproductive development and function is dependent upon testicular androgen production and is sensitive to antiandrogenic perturbations. It was of interest to determine if the H(1) histamine antagonist loratadine had the potential to alter androgen-mediated reproductive development in the rat, a sensitive species for detecting antiandrogenic effects. Loratadine was administered orally by gavage to pregnant Sprague-Dawley rats at doses of 4, 12 or 24 mg/kg from gestation day 7 to postnatal day 4, encompassing the period of androgen-dependent male reproductive development. Vehicle control rats received 0.4% aqueous methylcellulose. Dams were allowed to deliver naturally and rear their offspring until postnatal day 21. On postnatal day 21 male offspring were retained for further evaluation of androgen-dependent endpoints and the female offspring were euthanized and their sex confirmed internally. Males were necropsied from postnatal day 72 to 85. Dams administered 24 mg/kg of loratadine exhibited a transient 45% decrement in maternal body weight gain at the initiation of dosing (gestation days 7-9). Mean pup body weight on postnatal days 1 and 4 were approximately 4% lower than controls. No other effects on offspring growth were observed. Anogenital distance on postnatal day 1 was unaffected by loratadine exposure. Loratadine exposure did not induce the retention of nipples in male rats, affect preputial separation, or induce external malformations, including hypospadias. Seminal vesicle and prostate weights were not decreased by loratadine exposure. These data clearly demonstrate that systemic loratadine exposure, in multiples up to 26 times clinical exposure levels, does not exhibit in vivo antiandrogen activity, as evidenced by the absence of alterations or malformations in androgen-dependent reproductive tissues in male rats exposed to loratadine during the critical period of androgen-dependent development. PMID:14613821

McIntyre, Barry S; Vancutsem, Paul M; Treinen, Kimberley A; Morrissey, Richard E

2003-01-01

357

Ontogeny and morphology of the bulbus, part of the male reproductive organ in Apis mellifera carnica  

E-print Network

Ontogeny and morphology of the bulbus, part of the male reproductive organ in Apis mellifera 2011 Abstract ­ The bulbus is a part of the unique functional penis (endophallus) in the genus Apis and was studied in Apis mellifera drones. The bulbus consists of a thin cuticular membrane, covered by four

358

Student Organizations as Venues for Black Identity Expression and Development among African American Male Student Leaders  

ERIC Educational Resources Information Center

Ways in which membership in student organizations, both predominantly Black and mainstream, provide space for Black identity expression and development were explored in this study. Based on individual interviews conducted with African American male student leaders at six predominantly White universities, findings reveal a nexus between Black…

Harper, Shaun R.; Quaye, Stephen John

2007-01-01

359

Co-occurrence of antisocial behavior and substance use: testing for sex differences in the impact of older male friends, low parental knowledge and friends' delinquency.  

PubMed

Delinquency and substance use (SU) are commonly comorbid during adolescence. In the present study we investigate this co-morbidity with 3 main objectives: 1. Evaluate reciprocal relationships between delinquency/SU across early adolescence. 2. Assess the impact of older male friends, low parental knowledge and friends' delinquency on subsequent development and inter-relationships of delinquency and SU. 3. Evaluate sex differences in these relationships. We applied cross-lagged structural equation models to the analysis of a longitudinal sample (n=3699). Findings demonstrated: (1) At ages 13-14 delinquency predicted SU more so than vice versa but effects became equal between ages 14 and 15. (2) Low parental knowledge and friends' delinquency predicted delinquency and SU. Older male friends predicted ASB. (3) Sex differences were present. For example, in the absence of antisocial friends low parent knowledge at age 12 indirectly predicted increased age 15 SU for girls more than boys. PMID:24636685

McAdams, Tom A; Salekin, Randall T; Marti, C Nathan; Lester, Whiney S; Barker, Edward D

2014-04-01

360

Predictors of HIV Disclosure Among Untested, HIV-Negative and HIV-Positive Australian Men Who had Anal Intercourse with Their Most Recent Casual Male Sex Partner  

Microsoft Academic Search

We analysed HIV disclosure between Australian men who have sex with men (MSM) who reported anal intercourse with their last\\u000a casual male partner. Of 804 MSM included in the analysis, 413 reported HIV disclosure and 391 reported no disclosure. After\\u000a identifying bivariate associations with HIV disclosure, we developed three models of HIV disclosure (one for untested, one\\u000a for HIV-negative and

M. Holt; P. Rawstorne; H. Worth; M. Bittman; J. Wilkinson; S. Kippax

2011-01-01

361

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

Microsoft Academic Search

BackgroundAudio 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 FindingsWe 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

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

2009-01-01

362

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

Microsoft Academic Search

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,

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

2009-01-01

363

Prevalence and correlates of HIV and sexually transmitted infections among female sex workers and their non-commercial male partners in two Mexico-USA border cities.  

PubMed

Female sex workers (FSWs) acquire HIV and other sexually transmitted infections (STIs) through unprotected sex with commercial and non-commercial (intimate) male partners. Little research has focused on FSWs' intimate relationships, within which condom use is rare. We sought to determine the prevalence and correlates of HIV/STIs within FSWs' intimate relationships in Northern Mexico. From 2010 to 2011, we conducted a cross-sectional survey of FSWs and their non-commercial male partners in Tijuana and Ciudad Juárez, Mexico. Eligible FSWs and their verified male partners were aged ?18 years; FSWs reported lifetime use of heroin, cocaine, crack, or methamphetamine and recently exchanged sex (past month). Participants completed baseline questionnaires and testing for HIV, chlamydia, gonorrhea, and syphilis. We determined the prevalence and correlates of individuals' HIV/STI positivity using bivariate probit regression. Among 212 couples (n?=?424), prevalence of HIV was 2.6 % (n?=?11). Forty-two (9.9 %) tested positive for any HIV/STIs, which was more prevalent among women than men (12.7 % vs. 7.1 %, p?sex work clients were less likely to test positive for HIV/STIs than those without regular clients. Similarly, male partners of FSWs who had regular clients were 9 % less likely to have HIV/STIs. Higher sexual decision-making power was protective against HIV/STIs for women. Men who recently used methamphetamine or reported perpetrating any conflict within steady relationships were more likely to test positive for HIV/STIs. Within FSWs' intimate relationships in two Mexican-US border cities, nearly one in ten partners tested positive for HIV/STIs. Couple-based prevention interventions should recognize how intimate relationship factors and social contexts influence HIV/STI vulnerability. PMID:24488651

Robertson, Angela M; Syvertsen, Jennifer L; Ulibarri, Monica D; Rangel, M Gudelia; Martinez, Gustavo; Strathdee, Steffanie A

2014-08-01

364

Recalled Sexual Experiences in Childhood with Older Partners: A Study of Brazilian Men Who Have Sex with Men and Male-to-Female Transgender Persons  

Microsoft Academic Search

This study assessed the prevalence of recalled childhood sexual experiences with an older partner among men who have sex with\\u000a men (MSM) and\\/or male-to-female transgender persons recruited in Campinas, Brazil. It also analyzed associations between such\\u000a recalled experiences and sexual risk behavior in adulthood. Participants recruited using respondent driven sampling completed\\u000a a self-administered, computer-based questionnaire, and underwent HIV testing. For

Alex Carballo-Diéguez; Ivan Balan; Curtis Dolezal; Maeve B. Mello

365

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

PubMed Central

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

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

2014-01-01

366

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

PubMed

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

Ashman, Tia-Lynn; Penet, Laurent

2007-05-01

367

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

ERIC Educational Resources Information Center

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

Young, Phillip; Young, Karen Holsey

2010-01-01

368

The role of sexual imprinting for sex recognition in zebra finches: a difference between males and females  

Microsoft Academic Search

In sexually dimorphic birds, morphological characteristics are assumed to play an important role in conspecific sex recognition. In spite of the limited evidence, most studies done so far support this assumption. Less attention has been given to the question of how adult birds may have acquired the ability to discriminate between the sexes. This study investigates the relationship between the

Dave R. Vos

1995-01-01

369

Prevalence and factors of sexual problems in Chinese males and females having sex with the same-sex partner in Hong Kong: a population-based study  

Microsoft Academic Search

A cross-sectional, anonymous telephone survey was conducted to examine sexual problem (SP) among sexually active, Chinese homosexual adults in Hong Kong. Of the homosexual respondents, 49.1% of males and 75.6% of females reported at least one SP, of whom 36.0 and 65.7% of the males and females, respectively, felt very bothered by the SP. The prevalence of SP ranged from

J T F Lau; J H Kim; H-Y Tsui; JTF Lau

2006-01-01

370

Female sex pheromone blends and male response of the legume pod borer, Maruca vitrata (Lepidoptera: Crambidae), in two populations of mainland China.  

PubMed

The legume pod borer, Maruca vitrata (Lepidoptera: Crambidae; syn. M. testulalis), is a serious pantropical insect pest of grain legumes. Comparative studies of M. vitrata female sex pheromone components in two different geographic populations in China, Wuhan and Huazhou, confirmed that (E,E)-10,12-hexadecadienal (E10,E12-16:Ald) and (E)-10-hexadecenal (E10-16:Ald) were present in variable ratios in all pheromone gland extracts of both populations. (E,E)-10,12-hexadecadienol (E10,E12-16:OH) was always detected in minor amounts using polar DB-WAX columns, but was never detected using medium-polar DB-17 columns for the two populations. E10-16:OH was not found in any of the M. vitrata sex pheromone gland extracts. The average ratios of E10-16:Ald, E10,E12-16:Ald, and E10,E12-16:OH in the pheromone gland extracts of populations from Wuhan and Huazhou were 79.5:100:12.1 and 10.3:100:0.7, respectively. Electrophysiological testing suggested that E10,E12-16:Ald elicited the highest male electroantennography (EAG) response, followed by E10,E12-16:OH and E10-16:Ald. Field-trapping tests with single synthetic sex pheromone lures showed that E10,E12-16:OH alone could not attract males, whereas E10,E12-16:Ald or E10-16:Ald alone attracted few males. Wuhan and Huazhou males were most attracted by lures containing E10-16:Ald + E10,E12-16:Ald + E10,E12-16:OH in doses of (80 + 100 + 10) microg and (10 + 100 + 10) microg, respectively, per vial. Males could discriminate between the blends that were most attractive to their own geographic population and those that were most attractive to the reference population. Our findings suggest that geographic variation exists in the sex pheromone system of M. vitrata in China. The results are discussed with regard to the mechanisms underlying the sex pheromone variation. PMID:24459775

Lu, Peng-Fei; Qiao, Hai-Li; Luo, You-Qing

2013-01-01

371

Organ growth functions in maturing male Sprague-Dawley rats based on a collective database.  

PubMed

Ten different organ weights (liver, spleen, kidneys, heart, lungs, brain, adrenals, testes, epididymes, and seminal vesicles) of male Sprague-Dawley (S-D) rats of different ages (1-280 d) were extracted based on a thorough literature survey database. A generalized Michaelis-Menten (GMM) model, used to fit organ weights versus age in a previous study (Schoeffner et al., 1999) based on a limited data, was used to find the best fit model for the present expanded data compilation. The GMM model has the functional form: Wt = (Wt(o).K(gamma) + Wt(max).Age(gamma))/(K(gamma) + Age(gamma)) where Wt is organ/tissue weight at a specified age, Wt(o) and Wt(max) are weight at birth and maximal growth, respectively, and K and gamma are constants. Organ weights were significantly correlated with their respective ages for all organs and tissues. GMM-derived organ growth and percent body weight (%BW) fractions of different tissues were plotted against animal age and compared with experimental values as well as previously published models. The GMM-based organ growth and %BW fraction profiles were in general agreement with our empirical data as well as with previous studies. The present model was compared with the GMM model developed previously for six organs--liver, spleen, kidneys, heart, lungs, and brain--based on a limited data, and no significant difference was noticed between the two sets of predictions. It was concluded that the GMM models presented herein for different male S-D rats organs (liver, spleen, kidneys, heart, lungs, brain, adrenals, testes, epididymes, and seminal vesicles) are capable of predicting organ weights and %BW ratios accurately at different ages. PMID:17497417

Mirfazaelian, Ahmad; Fisher, Jeffrey W

2007-06-01

372

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

PubMed Central

Background Female sex workers (FSWs) may benefit from pre-exposure prophylaxis (PrEP) including microbicides for HIV prevention. Since adherence is a key factor in PrEP efficacy, we explored microbicide acceptability and potential barriers to use within FSWs’ intimate relationships in Tijuana and Ciudad Juárez, Mexico, where HIV prevalence is increasing. Methods FSWs and their verified intimate (non-commercial) male partners completed quantitative and qualitative interviews from 2010–2012. Our complementary mixed methods design followed an iterative process to assess microbicide acceptability, explore related relationship dynamics, and identify factors associated with concern about male partners’ anger regarding microbicide use. Results Among 185 couples (n=370 individuals), interest in microbicides was high. In qualitative interviews with 28 couples, most participants were enthusiastic about microbicides for sex work contexts but some explained that microbicides could imply mistrust/infidelity within their intimate relationships. In the overall sample, nearly 1 in 6 participants (16%) worried that male partners would become angry about microbicides, which was associated with higher self-esteem among FSWs and lower self-esteem and past year conflict causing injury within relationships among men. Conclusions HIV prevention interventions should consider intimate relationship dynamics posing potential barriers to PrEP acceptability and adherence, involve male partners, and promote risk communication skills. PMID:23398385

Robertson, Angela M.; Syvertsen, Jennifer L.; Martinez, Gustavo; Rangel, M. Gudelia; Palinkas, Lawrence A.; Stockman, Jamila K.; Ulibarri, Monica D.; Strathdee, Steffanie A.

2013-01-01

373

Learning to Discriminate the Sex of Conspecifics in Male Japanese Quail (Coturnix coturnix japonica ): Tests of Biological Constraints  

Microsoft Academic Search

Male Japanese quail learn to approach and remain near female, but not male, quail if they are allowed to copulate with female quail and receive noncopulatory exposures to males. The generality of the mechanisms involved in this type of discrimination learning was investigated in the present study. In Experiment 1, Ss learned to spend more time near initially unfamiliar blonde

Susan Nash; Michael Domjan

1991-01-01

374

Sex-Specific Differences in Hemodialysis Prevalence and Practices and the Male-to-Female Mortality Rate: The Dialysis Outcomes and Practice Patterns Study (DOPPS)  

PubMed Central

Background A comprehensive analysis of sex-specific differences in the characteristics, treatment, and outcomes of individuals with end-stage renal disease undergoing dialysis might reveal treatment inequalities and targets to improve sex-specific patient care. Here we describe hemodialysis prevalence and patient characteristics by sex, compare the adult male-to-female mortality rate with data from the general population, and evaluate sex interactions with mortality. Methods and Findings We assessed the Human Mortality Database and 206,374 patients receiving hemodialysis from 12 countries (Australia, Belgium, Canada, France, Germany, Italy, Japan, New Zealand, Spain, Sweden, the UK, and the US) participating in the international, prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) between June 1996 and March 2012. Among 35,964 sampled DOPPS patients with full data collection, we studied patient characteristics (descriptively) and mortality (via Cox regression) by sex. In all age groups, more men than women were on hemodialysis (59% versus 41% overall), with large differences observed between countries. The average estimated glomerular filtration rate at hemodialysis initiation was higher in men than women. The male-to-female mortality rate ratio in the general population varied from 1.5 to 2.6 for age groups <75 y, but in hemodialysis patients was close to one. Compared to women, men were younger (mean?=?61.9±standard deviation 14.6 versus 63.1±14.5 y), were less frequently obese, were more frequently married and recipients of a kidney transplant, more frequently had coronary artery disease, and were less frequently depressed. Interaction analyses showed that the mortality risk associated with several comorbidities and hemodialysis catheter use was lower for men (hazard ratio [HR]?=?1.11) than women (HR?=?1.33, interaction p<0.001). This study is limited by its inability to establish causality for the observed sex-specific differences and does not provide information about patients not treated with dialysis or dying prior to a planned start of dialysis. Conclusions Women's survival advantage was markedly diminished in hemodialysis patients. The finding that fewer women than men were being treated with dialysis for end-stage renal disease merits detailed further study, as the large discrepancies in sex-specific hemodialysis prevalence by country and age group are likely explained by factors beyond biology. Modifiable variables, such as catheter use, showing significant sex interactions suggest interventional targeting. Please see later in the article for the Editors' Summary PMID:25350533

Hecking, Manfred; Bieber, Brian A.; Ethier, Jean; Kautzky-Willer, Alexandra; Sunder-Plassmann, Gere; Saemann, Marcus D.; Ramirez, Sylvia P. B.; Gillespie, Brenda W.; Pisoni, Ronald L.; Robinson, Bruce M.; Port, Friedrich K.

2014-01-01

375

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

PubMed Central

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

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

376

Consistent condom use with regular, paying, and casual male partners and associated factors among men who have sex with men in Tamil Nadu, India: findings from an assessment of a large-scale HIV prevention program  

PubMed Central

Background Men who have sex with men (MSM) are a marginalized population at high risk for HIV infection. Promoting consistent condom use (CCU) during anal sex is a key risk reduction strategy for HIV prevention among MSM. To inform effective HIV prevention interventions, we examined the factors associated with CCU among MSM with their regular, paying, and casual partners, as well as with all three types of partners combined. Methods Data for this analysis were from a large-scale bio-behavioural survey conducted during 2009–2010 in Tamil Nadu, India. MSM aged 18 years or older were recruited for the survey using time-location cluster sampling at cruising sites in four districts of Tamil Nadu. Binary logistic regression analyses were conducted to assess the association of CCU with selected socio-demographic characteristics and other contextual factors. Results Among 1618 MSM interviewed, CCU during anal sex with regular, paying, and a casual male partner was 45.3%, 50.8% and 57.9%, respectively. CCU with all three types of partners combined was 52.6%. Characteristics associated with increased odds for CCU with MSM having all three types of partners combined were frequent receptive anal sex acts with regular partners (adjusted odds ratio [AOR] 2.17, 95% confidence interval [CI] 1.01-4.65), fewer number of casual partners (AOR 3.41, 95% CI 1.50-7.73) and membership in a community-based organization (CBO) for MSM (AOR 3.54, 95% CI 1.62-7.74). CCU with regular partners was associated with membership in a CBO (AOR 1.96, 95% CI 1.23-3.11), whereas CCU with paying, and casual male partners was associated with perceived higher risk of acquiring HIV (AOR 1.92, 95% CI 1.22-3.01) and exposure to any HIV prevention intervention (AOR 3.62, 95% CI 1.31-10.0), respectively. Being aged 26 years or older, being in debt, and alcohol use were factors associated with inconsistent condom use across partner types. Conclusion HIV interventions among MSM need to promote CCU with all types (regular, paying, and causal) of male partners, and need to reach MSM across all age groups. In addition to enhancing interventions that focus on individual level risk reduction, it is important to undertake structural interventions that promote social acceptance of same-sex sexuality and address contextual barriers to condom use such as alcohol use. PMID:24020613

2013-01-01

377

Genetic identification of two sibling species of Lutzomyia longipalpis (Diptera: Psychodidae) that produce distinct male sex pheromones in Sobral, Ceará State, Brazil.  

PubMed

Lutzomyia longipalpis, the main sandfly vector for New World visceral leishmaniasis is a complex of an as yet undefined number of sibling species. At present, there is no consensus on the status (single species vs. species complex) of Brazilian populations. We applied five microsatellite loci to test the hypothesis that L. longipalpis occurs as two sympatric cryptic species in Sobral, Ceará State, Brazil as predicted by male sex pheromone chemotypes described previously for field specimens from this site [S-9-methyl-germacrene-B (9MGB) and a cembrene compound]. Abdominal spot morphology corresponds with pheromone type at this locality (9MGB in '1 spot' males and cembrene in '2 spot' males). Genotype data from 190 wild-caught L. longipalpis specimens collected in October 1999 and April 2001 were used to estimate genetic differentiation between the two sex pheromone populations and sampling dates. No significant (P > 0.05) genetic differences were found between the 1999 and 2001 9MGB samples (theta = 0.018; RST = -0.005), and genetic differentiation was low between the cembrene collections (theta = 0.037, P < 0.05; RST = -0.043, P > 0.05). By contrast, highly divergent allelic frequencies (largely at two microsatellite loci) corresponded to significant (P > 0.05) genetic differentiation (theta = 0.221; RST = 0.215) for all comparisons between samples with different pheromones. When pheromone samples were pooled across sample date, genetic differentiation was high (theta = 0.229; P < 0.001; Nem = 0.84). The allele frequency distribution at each of the five microsatellite loci was similar for males and females from the two collection years. Two of these loci showed highly divergent allele frequencies in the two sex pheromone populations. This was reflected in the highly significant genetic differentiation obtained from the male genotypes, between populations producing different pheromones (theta = 0.229-0.268; P < 0.0001 for the 2001 and theta = 0.254-0.558; P < 0.0001 for the 1999 collections, respectively). Similar results were obtained when the females, assigned to a pheromone type, were included in the analysis. Both a Bayesian analysis of the data set and a population assignment test provided strong evidence for two distinct populations corresponding to pheromone type. Given its genotype, the probability of assigning a 9MGB male to the original 9MGB population was 100% once the two years' collections were pooled. For cembrene-producing '2 spot' males this probability although still high, was lower than for 9MGB males, at 86%. This microsatellite data together with previously reported reproductive isolation between the two Sobral populations confirm that premating barriers are important in speciation of L. longipalpis. PMID:12803639

Maingon, R D C; Ward, R D; Hamilton, J G C; Noyes, H A; Souza, N; Kemp, S J; Watts, P C

2003-07-01

378

Sex-specific parental care strategies via nestling age: females pay more attention to nestling demands than males do in the horned lark, Eremophila alpestris.  

PubMed

In many species, nestling demands vary continuously during early development and both parents have different parental care strategies at each nestling age. Sexual conflict arises when each parent expects its partner investing more in parental care. It is largely unknown how the two parents respond to the dynamics of nestling demands and resolve the sexual conflict during nestling period, especially on Qinghai-Tibetan Plateau. To address this question, we monitored parental care behaviors of horned larks (Eremophila alpestris) using video-recording systems. We found that male horned larks invested less in parental care, but had a larger body size than females, which is consistent with the parental investment hypothesis. Only the female brooded nestlings, but both parents contributed to feeding efforts. Feeding rates of males and females were negatively correlated, indicating that they used evolutionarily stable strategies. Strategies of parental care via nestling age were sex-specific. Females continuously adjusted care behaviors to follow the dynamics of nestling demands as nestling age increased, such as decreasing brood attentiveness and increasing feeding rate. By contrast, male feeding rate showed no significant correlation with nestling age, but increased with the synchrony feeding rate. We suggest the synchrony feeding behavior may act as a control measure for females to promote and assess the males' contribution. We consider low mating opportunities drive males to act as assistants for females, and correspondingly cause males to pay less attention to nestling demands than females. PMID:24882094

Liu, Chang-Jing; Du, Bo; Liu, Nai-Fa; Bao, Shi-Jie; Zhang, Shengxiang

2014-06-01

379

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

PubMed Central

In fiddler crabs both males and females defend territories that are essential for survival. Given pronounced sexual dimorphism in weaponry, how do weaponless females defend their territory from well-armed males? Using observational data and two simple experiments, we test whether male Uca annulipes protect their female neighbours from conspecific intruders. We show that males defend their female neighbours against male but not female intruders. We also show that females sometimes mate with their immediate neighbours. Male defence of female neighbours appears to represent both pre-copulatory mate-guarding and a territorial coalition. Males who ensure that their neighbour remains female could benefit through increased opportunity for future reproductive success and lower boundary maintenance costs. PMID:19889695

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

2010-01-01

380

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

E-print Network

Sex-Specific Genetic Structure and Social Organization in Central Asia: Insights from a Multi show that in patrilineal herder groups of Central Asia, in contrast to bilineal agriculturalists and Social Organization in Central Asia: Insights from a Multi-Locus Study. PLoS Genet 4(9): e1000200. doi:10

Paris-Sud XI, Université de

381

Sex differences, effects of male presence and coordination of nest visits in prairie voles (Microtus ochrogaster) during the immediate postnatal period  

USGS Publications Warehouse

Little is known about sex differences in parental behavior of biparental mammals and if mates in such species coordinate care of young. We studied parental care displayed by prairie voles (Microtus ochrogaster) under seminatural laboratory conditions during the first 3 d of life of their offspring. Through direct observations and videotaping, we monitored members of male-female pairs to determine if sex differences in early parental behavior exist and if mothers and fathers coordinate visits to the nest. To assess the impact of fathers on survival of pups and behavior of mothers, we also examined parental care displayed by single females toward their young. Male and female members of breeding pairs differed dramatically in degree of parental care. Females spent more time in the nest with young and licked them more frequently than did males. Additionally, females maintained the nest more frequently than did males, whereas they maintained runways less frequently. Although coordination of visits to the nest was not perfect between members of pairs, pups of pairs were left alone for less time than were pups of single females. Parental behavior displayed by paired and single females did not differ, nor did survival of their young to day 3 or 15. We suggest that provision of ample space and cover to vole parents rearing young in captivity promotes expression of sex differences in parental behavior, but that even seminatural conditions are not sufficient to yield benefits of father presence to survival of young. Under more challenging conditions, such as cold temperatures or presence of predators, benefits of father presence might emerge.

Mcguire, B.; Parker, E.; Bemis, W.E.

2007-01-01

382

A CUL-2 ubiquitin ligase containing three FEM proteins degrades TRA-1 to regulate C. elegans sex determination  

E-print Network

The nematode C. elegans has two sexes: male and hermaphrodite. The hermaphrodite has a female somatic body plan specialization in 40% of male cells and 30% of hermaphrodite cells (Sulston and Horvitz, 1977). Most tissues and organs differ between males and hermaphrodites, and therefore the sex determination pathway has

McQueen, Heather

383

Higher-order genome organization in platypus and chicken sperm and repositioning of sex chromosomes during mammalian evolution  

Microsoft Academic Search

In mammals, chromosomes occupy defined positions in sperm, whereas previous work in chicken showed random chromosome distribution.\\u000a Monotremes (platypus and echidnas) are the most basal group of living mammals. They have elongated sperm like chicken and\\u000a a complex sex chromosome system with homology to chicken sex chromosomes. We used platypus and chicken genomic clones to investigate\\u000a genome organization in sperm.

Enkhjargal Tsend-Ayush; Natasha Dodge; Julia Mohr; Aaron Casey; Heinz Himmelbauer; Colin L. Kremitzki; Kyriena Schatzkamer; Tina Graves; Wesley C. Warren; Frank Grützner

2009-01-01

384

Study on The Reproductive Organs and Fertility of The Male Mice following Administration of Metronidazole  

PubMed Central

Background: Metronidazole (MTZ) is commonly used as an antibacterial and antiprotozoal drug. Various doses of MTZ have been reported to inhibit spermatogenic activity and sperm indices. Materials and Methods: In this experimental study, dose-dependent effects of MTZ on the structural and functional integrity of the testis and accessory reproductive organs have been investigated. Adult male mice of Swiss strain were administered orally with MTZ at the doses of 250 mg/kgBW/day and 500 mg/kgBW/day for 28 consecutive days to study the changes in the testis, epididymis, seminal vesicle, sperm indices and fertility. Reversal effects of the drug were also studied on the same mice, 42 days after cessation of the treatment. Results: Therapeutic dose of MTZ (250 mg/kgBW/day) neither altered the weights of the testis, epididymis and seminal vesicle nor their histoarchitecture and sperm indices. The drug at the high dose (500 mg/kg BW/day) caused significant reductions in the weights of the testis and epididymis. Histoarchitecture of the testis and epididymis at the high dose revealed marked regressive changes while that of seminal vesicle remained unaffected. Significant reductions were noticed in the motility, viability and count of epididymal spermatozoa while the concentrations of epididymal sialic acid and seminal vesicular fructose remained unaltered after the treatment. No significant changes were noticed in the mating ability as well as in the level of serum testosterone in the treated mice. Fertility of the male mice treated with high dose of MTZ declined markedly leading to an increase in pre- and postimplantation loss while a significant decrease was noticed in the number of live blastocysts in females impregnated with such males. MTZinduced changes in the male reproductive organs and fertility were reinstated 42 days after cessation of the treatment. Conclusion: High dose of MTZ induced reversible deleterious effects on the male reproduction and fertility. PMID:24520490

Kumari, Mrinalini; Singh, Poonam

2013-01-01

385

Synergistic Effect of Fadrozole and Insulin-Like Growth Factor-I on Female-To-Male Sex Reversal and Body Weight of Broiler Chicks  

PubMed Central

The aim of this study was to investigate the effects of Fadrozole hydrochloride and recombinant human insulin-like growth factor I (rhIGF-I) on female-to-male sex reversal, hatching traits, and body weight of broiler chickens. On the third day of incubation, fertile eggs were randomly assigned to five experimental groups comprising (i) Fadrozole (0.1 mg/egg), (ii) rhIGF-I (100 ng/egg), (iii) Fadrozole (0.1 mg/egg) + rhIGF-I (100 ng/egg), (iv) vehicle injection (10 mM acetic acid and 0.1% BSA), and (v) non-injected eggs. Eggs in the rhIGF-I-injected groups showed the mode of hatching time at the 480th hour of incubation, 12 hours earlier compared to the other groups, with no statistically significant difference in mortality and hatchability. On Day 1 and 42 of production, 90% of genetically female chicks were masculinized using Fadrozole treatment, while 100% female-to-male phenotypic sex reversal was observed in the Fadrozole+rhIGF-I group. Fadrozole equalized the body weight of both genders, although rhIGF-I was effective on the body weight of male chicks only. Interestingly, combined rhIGF-I and Fadrozole could increase the body weight in both sexes compared to the individual injections (P<0.05). These findings revealed that (i) IGF-I-treated chicken embryos were shown to be an effective option for overcoming the very long chicken deprivation period, (ii) the simultaneous treatment with Fadrozole and IGF-I could maximize the female-to-male sex reversal chance, (iii) the increase in the body weight of masculinized chickens via Fadrozole could be equal to their genetically male counterparts, and (iv) the IGF-I effectiveness, specifically along with the application of aromatase inhibitors in female chicks, indicates that estrogen synthesis could be a stumbling block for the IGF-I action mechanism in female embryos. PMID:25075864

Mohammadrezaei, Mohammad; Toghyani, Majid; Gheisari, Abbasali; Toghyani, Mehdi; Eghbalsaied, Shahin

2014-01-01

386

All-male hybrid ( Cherax albidus× Cherax rotundus) yabbies grow faster than mixed-sex ( C. albidus× C. albidus) yabbies  

Microsoft Academic Search

This study shows that the use of the all-male progeny produced from hybridising the female freshwater crayfish, Cherax rotundus, and the male, Cherax albidus, offers considerable potential for eliminating the growth-suppressing uncontrolled reproduction that occurs in commercial ponds prior to harvest; a major limiting factor in commercial yabby (C. albidus) farming in Australia. Juveniles of all-male progeny of hybrid crosses

Craig S Lawrence

2004-01-01

387

Response of males to female sex pheromone in the orange wheat blossom midge, Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae)  

Microsoft Academic Search

Males of the orange wheat blossom midge,Sitodiplosis mosellana (Géhin), were attracted by female but not by male extract in a Y-tube bioassay. In laboratory mating experiments, females exhibited typical calling behavior under all conditions tested. At 19‡C in the dark, males exhibited a high frequency of wing vibration (a courtship behavior) and mating attempts, and 68% of females were mated.

Kenneth A. Pivnick

1993-01-01

388

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

PubMed

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

Saadat, Mostafa; Bahaoddini, Samaneh; Saadat, Iraj

2013-03-01

389

Effect of single-sex or mixed rearing and live weight on performance, technological meat quality and sexual maturity in entire male and female pigs fed raw potato starch  

Microsoft Academic Search

The aim of our study was to investigate the effect of rearing system (mixed or single-sex) on performance and carcass quality of entire male and female pigs slaughtered at around 90 or 115 kg live weight. We also studied the combined effect of live weight and dietary supplement of raw potato starch (RPS) on technological meat quality for both sexes,

H. Kristina Andersson; Kjell Andersson; Galia Zamaratskaia; Lotta rydhmer; Gang Chen; Kerstin Lundström

2005-01-01

390

Male Sex Workers in Moscow, Russia: A Pilot Study of Demographics, Substance Use Patterns, and Prevalence of HIV-1 and Sexually Transmitted Infections  

PubMed Central

Background To explore demographic characteristics, substance use patters, and estimate the prevalence of sexually transmitted infections (STI) and high-risk behaviors among male sex workers (MSW) in Moscow and to assess the feasibility of prospective cohort recruitment and retention among this population. Methods Longitudinal study of 50 men with 6 month follow up period. Participants were recruited through venue based and snowball sampling. Results HIV prevalence at baseline was 16% and 1 male seroconverted during the follow up period. 24 % were diagnosed with at least one STI: 12% had syphilis; 8% had HPV;, and 4% had HSV-2. Three (6%) of the study participants had evidence of previous HCV exposure at baseline. Conclusions This was the first study to evaluate baseline demographics, substance use patterns, and prevalence of infectious disease among MSW in Moscow. Identification, and recruitment of this population appears to be feasible, but retention rates were poor with higher retention significantly associated with older men. While the sample size in the current study was small, the results also suggested that this is a population at considerable high risk for HIV. Male sex workers in Moscow may be an important at risk population in the Russian HIV epidemic and further research is urgently required to address their needs and explore prevention strategies. PMID:20390488

Baral, Stefan; Kizub, Darya; Masenior, Nicole Franck; Peryskina, Alena; Stachowiak, Julie; Stibich, Mark; Moguilny, Vladimir; Beyrer, Chris

2014-01-01

391

Chemical composition of scent-gland secretions in an old world monkey (Mandrillus sphinx): influence of sex, male status, and individual identity.  

PubMed

Primates are traditionally considered to be microsmatic, with decreased reliance on olfactory senses in comparison to other sensory modalities such as vision. This is particularly the case for Old World monkeys and apes (catarrhines). However, various lines of evidence suggest that chemical communication may be important in these species, including the presence of a sternal scent-gland in the mandrill. We investigated the volatile components of mandrill odor using gas chromatography-mass spectrometry. We identified a total of 97 volatile components in 88 swabs of the sternal gland secretion and 95 samples of sternal gland hair saturated with scent-gland secretion collected from 27 males and 18 females. We compared odor profiles with features of the signaler using principle components and discriminant function analyses and found that volatile profiles convey both variable (age, dominance rank in males) and fixed (sex, possibly individual identity) information about the signaler. The combination of an odor profile that signals sex, age, and rank with increased motivation to scent-mark and increased production of secretion in high-ranking males leads to a potent signal of the presence of a dominant, adult male with high testosterone levels. This may be particularly relevant in the dense Central African rain forest which mandrills inhabit. By contrast, we were unable to differentiate between either female cycle stage or female rank based on odor profiles, which accords with behavioral studies suggesting that odor signals are not as important in female mandrills as they are in males. The similarity of our findings to those for other mammals and in primates that are more distantly related to humans suggests a broader role for odor in primate communication than is currently recognized. PMID:20089603

Setchell, Joanna M; Vaglio, Stefano; Moggi-Cecchi, Jacopo; Boscaro, Francesca; Calamai, Luca; Knapp, Leslie A

2010-03-01

392

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

PubMed Central

The HIV/AIDS epidemic in South Africa has largely focused on the needs of heterosexual men and women. However, little is known about the sexual risk histories of men who have sex with both men and women (MSMW). Furthermore, we know very little about the psychosocial health needs or of the possibility of a syndemic (numerous interrelated epidemics) among MSMW. We surveyed 1,203 men attending drinking establishments in a township located in Cape Town, South Africa. We compared the behaviors and experiences of MSMW to men reporting only having sex with women (MSW). Twelve percent of the sample reported having sex with both men and women in the past four months. MSMW were twice as likely as MSW to report being HIV positive (10.5% vs. 4.6%). MSW were more likely to be married than MSMW but reported similar numbers of female sex partners. MSMW were more likely to report a history of childhood sexual abuse, recent experienced and perpetrated physical and sexual partner violence, both receiving and giving sex for money, drugs, or shelter, and a recent STI. These factors were found to be interrelated among MSW but not MSMW. Although MSMW demonstrate considerable risk taking and report higher rates of HIV infection than MSW, their needs are largely unmet and underemphasized. Findings suggest the need to better understand factors contributing to sexual risk taking among MSMW. HIV prevention interventions should consider psychosocial health problems unique to MSMW residing in South African townships. PMID:23519592

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

2013-01-01

393

Sex in the dark: determinants and consequences of mixed male mating tactics in Microcebus murinus , a small solitary nocturnal primate  

Microsoft Academic Search

In mammals with solitary females, the potential for males to monopolize matings is relatively low, and scramble competition polygyny is presumed to be the predominant mating system. However, combinations of male traits and mating tactics within this type of polygyny have been described. The main aim of our study was to identify the relative importance of, and interactions among, potential

Manfred Eberle; Peter M. Kappeler

2004-01-01

394

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

PubMed

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

Binnington, Matthew J; Wania, Frank

2014-06-01

395

Inconsistent condom use by male clients during anal intercourse with occasional and regular female sex workers (FSWs): survey findings from southern states of India  

PubMed Central

Objectives Self-reported anal intercourse by female sex workers (FSWs) documented in recent studies from India range between 11.9% and 22%. However, comparable data on anal intercourse and condom use from male clients of FSWs is lacking. Using data from a bio-behavioural survey (2009–2010), we examined prevalence of anal intercourse, male clients’ self-reported inconsistent condom use during anal intercourse with FSWs, and correlates of this behaviour in India's high HIV prevalence southern states (Andhra Pradesh, Maharashtra and Tamil Nadu combined). Methods Using two-stage time location cluster sampling, we recruited 4803 clients of FSWs, ages 18–60?years, who had purchased sex from an FSW in the past month. After obtaining informed consent, respondents were interviewed and tested for HIV and sexually transmitted infections (syphilis, gonorrhoea and chlamydia). Logistic regression analysis was used to identify the factors associated with inconsistent condom use during anal intercourse (in the past 6?months) with FSWs. Results Overall, 12.3% clients reported anal intercourse in the past 6?months, of whom 48.4% used condoms inconsistently. Clients of FSWs who were ages 26?years or older (AOR 2.68, p=0.032); employed as manual labourers (AOR 2.43, p=0.013); consumed alcohol (AOR 2.63, p=0.001); reported five or more sex acts with FSWs in the past month (AOR 2.53, p=0.031); and perceived themselves to be at higher risk for HIV (AOR 4.82, p=0.001) were more likely to inconsistently use condoms during anal intercourse. Conclusions The results suggest that sex workers and their clients commonly practice anal intercourse, but a relatively high proportion of clients do not consistently use condoms, leading to a greater risk of acquiring HIV and its further transmission to other male and female sexual partners. Given the multidirectional risk, safer sex communication on heterosexual anal intercourse must be incorporated into HIV prevention programmes. PMID:25410604

Ramanathan, Shreena; Nagarajan, Karikalan; Ramakrishnan, Lakshmi; Mainkar, Mandar K; Goswami, Prabuddhagopal; Yadav, Diwakar; Sen, Shrabanti; George, Bitra; Rachakulla, Harikumar; Subramanian, Thilakavathi; Paranjape, Ramesh S

2014-01-01

396

Sex differences in a mouse model of multiple sclerosis: neuropathic pain behavior in females but not males and protection from neurological deficits during proestrus  

PubMed Central

Background Multiple sclerosis (MS), a demyelinating disease of the central nervous system, is one of the most prevalent neurological disorders in the industrialized world. This disease afflicts more than two million people worldwide, over two thirds of which are women. MS is typically diagnosed between the ages of 20–40 and can produce debilitating neurological impairments including muscle spasticity, muscle paralysis, and chronic pain. Despite the large sex disparity in MS prevalence, clinical and basic research investigations of how sex and estrous cycle impact development, duration, and severity of neurological impairments and pain symptoms are limited. To help address these questions, we evaluated behavioral signs of sensory and motor functions in one of the most widely characterized animal models of MS, the experimental autoimmune encephalomyelitis (EAE) model. Methods C57BL/6 male and female mice received flank injection of complete Freund’s adjuvant (CFA) or CFA plus myelin oligodendrocyte glycoprotein 35-55 (MOG35-55) to induce EAE. Experiment 1 evaluated sex differences of EAE-induced neurological motor deficits and neuropathic pain-like behavior over 3 weeks, while experiment 2 evaluated the effect of estrous phase in female mice on the same behavioral measures for 3 months. EAE-induced neurological motor deficits including gait analysis and forelimb grip strength were assessed. Neuropathic pain-like behaviors evaluated included sensitivity to mechanical, cold, and heat stimulations. Estrous cycle was determined daily via vaginal lavage. Results MOG35-55-induced EAE produced neurological impairments (i.e., motor dysfunction) including mild paralysis and decreases in grip strength in both females and males. MOG35-55 produced behavioral signs of neuropathic pain—mechanical and cold hypersensitivity—in females, but not males. MOG35-55 did not change cutaneous heat sensitivity in either sex. Administration of CFA or CFA?+?MOG35-55 prolonged the time spent in diestrus for 2 weeks, after which normal cycling returned. MOG35-55 produced fewer neurological motor deficits when mice were in proestrus relative to non-proestrus phases. Conclusions We conclude that female mice are superior to males for the study of neuropathic pain-like behaviors associated with MOG35-55-induced EAE. Further, proestrus may be protective against EAE-induced neurological deficits, thus necessitating further investigation into the impact that estrous cycle exerts on MS symptoms. PMID:24581045

2014-01-01

397

Synthesis of syn-4,6-dimethyldodecanal, the male sex pheromone and trail-following pheromone of two species of the termite Zootermopsis.  

PubMed

Recently, we reported that syn-4,6-dimethyldodecanal is the male sex pheromone and the trail-following pheromone of the Termopsidae Zootermopsis nevadensis and Zootermopsis angusticollis. In this article, we describe the syntheses of the mixture of the four stereoisomers of 4,6-dimethyldodecanal using a synthetic pathway where the key step is a Wittig reaction between methyl 4-methyl-5-oxo-pentanoate and 1-methylheptyl-triphenylphosphonium iodide, and of (±)-syn-4,6-dimethyldodecanal starting from 3,5-dimethyl-2-cyclohexen-1-one. Direct GC-MS comparison of these synthetic samples with the natural pheromone allowed its unambiguous identification. PMID:21391118

Ghostin, J; Bordereau, C; Braekman, J C

2011-03-01

398

Sex workers, fem queens, and cross-dressers: Differential marginalizations and HIV vulnerabilities among three ethnocultural male-to-female transgender communities in New York City  

Microsoft Academic Search

This article describes 3 distinct ethnocultural male-to-female transgender communities in New York City: the low-income African\\u000a American\\/Black1 and Latina(o) House Ball community; low-income, often undocumented immigrant Asian sex workers; and middle-class White cross-dressers.\\u000a These communities are highly socially isolated from each other and are more connected to their ethnocultural contexts than\\u000a to an abstract and shared transgender identity. Whereas previous

Sel Julian Hwahng; Larry Nuttbrock

2007-01-01

399

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

ERIC Educational Resources Information Center

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

Sheridan, Jennifer T.

400

Sexual Abuse Histories of Adolescent Male Sex Offenders: Differences on the Basis of the Age and Gender of Their Victims  

Microsoft Academic Search

Childhood sexual abuse has often been implicated in the etiology of adolescent sex offending behavior. Victimization rates in the literature vary according to whether data are collected prior (22%) or subsequent (52%) to treatment. Previous research suggests that the incidence of sexual abuse varies as a function of victim age and gender. Sexual abuse histories were collected from 87 adolescent

James R. Worling

1995-01-01

401

Condition dependence and the nature of genetic variation for male sex comb bristle number in Drosophila melanogaster  

E-print Network

in Drosophila melanogaster Abha Ahuja · Scott De Vito · Rama S. Singh Received: 5 August 2010 / Accepted: 23 was manipulated in a set of ten Drosophila melanogaster full- sib families. We confirmed heightened condition. Keywords Condition dependence Á Drosophila melanogaster Á Sex comb Á Condition Á Genetic variation

Alwes, Frederike

402

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

PubMed

Few data exist on the early sexual behavior patterns of contemporary young men who have sex with men (YMSM), the social context of these patterns, and which of these factors influence risk for HIV and other sexually transmitted infections (STI). We enrolled 94 YMSM (age 16-30) into a 1-year cohort study with serial online retrospective surveys and HIV/STI testing. The first three partnerships of YMSM were characterized by relatively high rates of unprotected anal sex and a rapidly expanding sexual repertoire, but also increasing rates of HIV status disclosure. During follow-up, 17 % of YMSM reported any nonconcordant unprotected anal intercourse (NCUAI) and 15 % were newly diagnosed with HIV/STI. Sex education in high school and current maternal support were protective against HIV/STI, while isolation from family and friends was associated with recent NCUAI. Social support-including from parents, peers, and school-based sex education-may help mitigate HIV/STI risk in this population. PMID:24356869

Glick, Sara Nelson; Golden, Matthew R

2014-08-01

403

Female brown-headed cowbirds', Molothrus ater, organization and behaviour reflects male social dynamics  

Microsoft Academic Search

In four large aviaries, we studied social assortment and reproductive behaviour of female brown-headed cowbirds housed with males differing in age class and in corresponding levels of intrasexual interaction. Juvenile and adult females resided with either (1) adult males, (2) juvenile males, (3) adult and juvenile males, or (4) no males. We observed social behaviour of males and females from

Meredith J. West; David J. White; Andrew P. King

2002-01-01

404

Tactics for male reproductive success in plants: contrasting insights of sex allocation theory and pollen presentation theory  

E-print Network

expression in plants, followed by an account of some 25 recent comparative work. Hermaphroditism is more with the fact that hermaphrodites achieve fitness through potentially conflicting male and female functions

Thomson, James D.

405

Circuits attenuating seizures under well-fed and food-deprived conditions in C. elegans male sex muscles  

E-print Network

. Specifically, I focused on the step wherein the male inserts his copulatory spicules into the hermaphrodite vulva, as vulva penetration is required for successful sperm transfer. This step must be tightly regulated; if the spicules protract too soon...

Leboeuf, Brigitte L.

2010-07-14

406

Structure and development of the internal male reproductive organs in the dragonfly Tramea virginia (Rambur).  

PubMed

The internal male reproductive organs of Tramea virginia consist of a pair of testes, a pair of vasa deferentia (which in adult modify distally into seminal vesicles), a median sperm sac and a short ejaculatory duct. The development of the genital tract occurs in the ultimate nymph. Each testicular lobule contains the gametes showing collectively only a single stage of spermatogenesis. The process of spermatogenesis is vigorous in the ultimate nymph and, therefore, the newly emerged imago contains active spermatozoa in its testicular lobules. Spermatophores are not observed in the genital tract of the adults. PMID:8286796

Andrew, R J; Tembhare, D B

1993-01-01

407

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

PubMed Central

Background Rising HIV infection rates have been observed among elderly people in Guangxi, China. Inexpensive aphrodisiacs are available for purchase in suburban and rural areas. This study aims to investigate the association between aphrodisiac use and increased HIV risk for middle-aged and elderly men in Guangxi. Methods A matched case-control study of aphrodisiac use-associated HIV infection was performed among male subjects over 50 years old who were clients of low-cost commercial sex venues in Guangxi. The cases were defined as clients who were HIV-positive and two controls were selected for each case. The cases and the controls were matched on the visited sex venue, age (±3 years), number of years of purchasing sex (±3 years), and educational attainment. Subjects were interviewed and tested for HIV. Paired t-test or McNemar Chi-squared test were used to compare the characteristics between the cases and controls. A stepwise conditional logistic regression was used to identify risk factors associated with HIV infection. Findings This study enrolled 103 cases and 206 controls. Aphrodisiac use (P?=?0.02, odds ratio (OR)?=?1.81, 95% CI?=?1.08–3.04), never using condom during commercial sex encounter (P?=?0.03, odds ratio (OR)?=?1.82, 95% CI?=?1.08–3.07), and lacking a stable partner (P?=?0.03, odds ratio (OR)?=?1.76, 95% CI?=?1.05–2.98) were found to be risk factors for HIV infection among the study groups. For subjects reporting aphrodisiac use, the frequency of purchasing sex was positively correlated with the frequency of aphrodisiac use (r?=?0.3; p?=?0.02). Conclusions Aphrodisiac use was significantly associated with increased HIV infection risk in men over 50 years old who purchased commercial sex in the suburban and rural areas of Guangxi. Further research and interventions should address the links between aphrodisiac use, commercial sex work, condom use, and increased HIV transmission. PMID:25286369

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

2014-01-01

408

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

PubMed

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

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

2010-08-01

409

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

ERIC Educational Resources Information Center

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

Lewis, Michael

410

Antenna-predominant and male-biased CSP19 of Sesamia inferens is able to bind the female sex pheromones and host plant volatiles.  

PubMed

Insect chemosensory proteins (CSPs) are proposed to capture and transport hydrophobic chemicals across the sensillum lymph to olfactory receptors (ORs), but this has not been clarified in moths. In this study, we built on our previously reported segment sequence work and cloned the full length CSP19 gene (SinfCSP19) from the antennae of Sesamia inferens by using rapid amplification of cDNA ends. Quantitative real time-PCR (qPCR) assays indicated that the gene was expressed in a unique profile, i.e. predominant in antennae and significantly higher in male than in female. To explore the function, recombinant SinfCSP19 was expressed in Escherichia coli cells and purified by Ni-ion affinity chromatography. Binding affinities of the recombinant SinfCSP19 with 39 plant volatiles, 3 sex pheromone components and 10 pheromone analogs were measured using fluorescent competitive binding assays. The results showed that 6 plant volatiles displayed high binding affinities to SinfCSP19 (Ki = 2.12-8.75 ?M), and more interesting, the 3 sex pheromone components and analogs showed even higher binding to SinfCSP19 (Ki = 0.49-1.78 ?M). Those results suggest that SinfCSP19 plays a role in reception of female sex pheromones of S. inferens and host plant volatiles. PMID:24361960

Zhang, Ya-Nan; Ye, Zhan-Feng; Yang, Ke; Dong, Shuang-Lin

2014-02-25

411

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

SciTech Connect

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

Mohandas, T.K.; Passage, M.B.; Yen, P.H.; Speed, R.M.; Chandley, A.C.; Shapiro, L.J. (Univ. of California, San Francisco, CA (United States))

1992-09-01

412

Effects of medroxyprogesterone acetate on subjective arousal, arousal to erotic stimulation, and nocturnal penile tumescence in male sex offenders  

Microsoft Academic Search

Three chronic pedophiliac sex offenders were treated individually with medroxyprogesterone acetate (MPA) over a minumum of 3 months. Genital and subjective response to erotic stimulation, nocturnal penile tumescence, self-reporting of sexual urges, and testosterone levels were recorded repeatedly throughout the study. A single-subject reversal design was used and medication was administered through a double-blind procedure. The results showed that self-report

John P. Wincze; Sudhir Bansal; Mark Malamud

1986-01-01

413

Cortisol Levels and Corticosteroid Administration Fail to Predict Mortality in Critical Illness The Confounding Effects of Organ Dysfunction and Sex  

Microsoft Academic Search

Background: Corticosteroid supplementation based on plasma cortisol measurement was reported to decrease mortality in vasopressor-dependent critical illness. Hypothesis: Random levels or maximal increments of plasma cortisol measured after short adrenal stimulation may predict mortality independent of concurrent organ dysfunction or sex, and corticosteroid supplementation may decrease mortality in vasopressor-dependent criti- cal illness. Design: An observational descriptive study. Patients: Critically ill

Bhavesh Patel; Joel Larson; Richard Helmers

2005-01-01

414

Caste and sex specific olfactory glomerular organization and brain architecture in two sympatric ant species Camponotus sericeus and Camponotus compressus  

E-print Network

Caste and sex specific olfactory glomerular organization and brain architecture in two sympatric Accepted 8 June 2009 Keywords: Ants Antennal lobes Glomeruli Morphological castes a b s t r a c t We use the architecture of the antennal lobes in different castes of two ant species ­ Camponotus seri- ceus

415

Can Sex Differences in Science Be Tied to the Long Reach of Prenatal Hormones? Brain Organization Theory, Digit Ratio (2D/4D), and Sex Differences in Preferences and Cognition  

PubMed Central

Brain organization theory posits a cascade of physiological and behavioral changes initiated and shaped by prenatal hormones. Recently, this theory has been associated with outcomes including gendered toy preference, 2D/4D digit ratio, personality characteristics, sexual orientation, and cognitive profile (spatial, verbal, and mathematical abilities). We examine the evidence for this claim, focusing on 2D/4D and its putative role as a biomarker for organizational features that influence cognitive abilities/interests predisposing males toward mathematically and spatially intensive careers. Although massive support exists for early brain organization theory overall, there are myriad inconsistencies, alternative explanations, and outright contradictions that must be addressed while still taking the entire theory into account. Like a fractal within the larger theory, the 2D/4D hypothesis mirrors this overall support on a smaller scale while likewise suffering from inconsistencies (positive, negative, and sex-dependent correlations), alternative explanations (2D/4D related to spatial preferences rather than abilities per se), and contradictions (feminine 2D/4D in men associated with higher spatial ability). Using the debate over brain organization theory as the theoretical stage, we focus on 2D/4D evidence as an increasingly important player on this stage, a demonstrative case in point of the evidential complexities of the broader debate, and an increasingly important topic in its own right. PMID:22164187

Valla, Jeffrey; Ceci, Stephen J.

2011-01-01

416

High prevalence of HIV and sexually transmitted infections among male sex workers in Abidjan, Côte d'Ivoire: need for services tailored to their needs  

PubMed Central

Objectives To assess condom use and prevalence of sexually transmitted infections (STI) and HIV among male sex workers (MSW) in Abidjan, Côte d'Ivoire. Methods A cross-sectional survey was conducted between October 2007 and January 2008 among MSW attending a sex worker clinic in Abidjan. A short questionnaire was administered in a face-to-face interview, and the participants were asked to provide a urine sample for STI testing and to self-collect transudate of the gingival mucosa for anonymous HIV testing, using a rapid test. A rectal swab for STI testing was taken by a physician. Molecular amplification assays were performed for the detection of Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis. Results 96 MSW participated in the survey, their median age was 27?years and the median duration of sex work was 5?years. Consistent condom use with clients during the last working day was 86.0%, and consistent condom use with the regular partner during the last week was 81.6%. HIV infection was detected in 50.0% of the participants. The prevalence of N gonorrhoeae was 12.8%, chlamydia infection was present in 3.2% and T vaginalis in 2.1% of the study participants. Conclusions HIV and STI rates found in this study confirm the high risk and vulnerability status of MSW in Côte d'Ivoire. There is a definite need for studies exploring risk and risk perceptions among MSW in more depth and for services tailored to their needs, including developing and validating simple algorithms for the diagnosis of STI in MSW and men who have sex with men. PMID:22328644

Semde, Gisèle; Sika, Lazare; Crucitti, Tania; Ettiegne Traore, Virginie; Buve, Anne; Laga, Marie

2012-01-01

417

Influence of temperature stimulation during the last 4 days of incubation on secondary sex ratio and later performance in male and female broiler chicks.  

PubMed

1. In 6 incubation trials a total of 9883 eggs (Ross 308) were incubated from d 1 to 17 under normal incubation conditions (37.2-37.4 degrees C) and then sorted into three hatch incubators (control: 37.2-37.4 degrees C; chronic warm incubation: 38.2-38.4 degrees C, 24 h daily; short-term warm stimulation: 38.2-38.4 degrees C, 2 h daily) in incubation trials 1 and 2 or two hatch incubators (control and short-term warm stimulation) in trials 3-6. 2. The one-day-old chicks were selected by sex and chick quality was analysed in random samples using the Pasgar score. A total of 120 male and 120 female one-day-old chickens from each incubator were used for a 35-d fattening period. 3. Neither chronic nor short-term increase in incubation temperature had a negative effect on hatchability and chick quality. Short-term warm stimulation improved hatchability by more than 1.5% and was associated with a significantly higher proportion of hatched male chicks. 4. In the subsequent broiler growth trial, the mean daily weight gain of the short-term warm stimulated male broiler chicks was significant higher than for the control group, which results in a body weight increase of 2.9%. 5. Feed conversion (feed:gain ratio) of the short-term warm stimulated male and female broilers was significantly lower than in the males and females of the control and chronic warm incubated groups. 6. In conclusion, an incubation temperature profile which includes short-term temperature variation can be important in improving poultry performance (European patent pending since March 2008). PMID:19904643

Tzschentke, B; Halle, I

2009-09-01

418

Higher-order genome organization in platypus and chicken sperm and repositioning of sex chromosomes during mammalian evolution.  

PubMed

In mammals, chromosomes occupy defined positions in sperm, whereas previous work in chicken showed random chromosome distribution. Monotremes (platypus and echidnas) are the most basal group of living mammals. They have elongated sperm like chicken and a complex sex chromosome system with homology to chicken sex chromosomes. We used platypus and chicken genomic clones to investigate genome organization in sperm. In chicken sperm, about half of the chromosomes investigated are organized non-randomly, whereas in platypus chromosome organization in sperm is almost entirely non-random. The use of genomic clones allowed us to determine chromosome orientation and chromatin compaction in sperm. We found that in both species chromosomes maintain orientation of chromosomes in sperm independent of random or non-random positioning along the sperm nucleus. The distance of loci correlated with the total length of sperm nuclei, suggesting that chromatin extension depends on sperm elongation. In platypus, most sex chromosomes cluster in the posterior region of the sperm nucleus, presumably the result of postmeiotic association of sex chromosomes. Chicken and platypus autosomes sharing homology with the human X chromosome located centrally in both species suggesting that this is the ancestral position. This suggests that in some therian mammals a more anterior position of the X chromosome has evolved independently. PMID:18726609

Tsend-Ayush, Enkhjargal; Dodge, Natasha; Mohr, Julia; Casey, Aaron; Himmelbauer, Heinz; Kremitzki, Colin L; Schatzkamer, Kyriena; Graves, Tina; Warren, Wesley C; Grützner, Frank

2009-02-01

419

[Modulating effects of androgens on development adaptive-compensatory processes in organism of experimental animals-males].  

PubMed

The purpose of research is the definition of androgens role and myocardial androgen receptors and sex steroids in males under metabolic and hormonal "stress" induced by the experimental diabetes. Research was carried out on 60 rats-males, mass 180,0-200,0 g. The diabetes reproduced by single injection of alloxan (200mg/kg). Androgen receptors were revealed by the radiometric and radioautography methods. The content of glucose, immunoreactive insulin, testosteron, estradiol, corticosteron and somatotropin were defined in animals blood plasma. On the early terms of alloxan diabetes estradiol concentration increase against a background of testosteron decrease which causes the "feminization" of the sexual hormonal balance. On the other side the increase of androgen receptors expression by cardiomyocytes causes the intensification of myocardium tissue physiologic ability to androgens perception positively influencing on the metabolism. Consequently, androgens provoke stimulating effect on the myocard metabolism in males at