Knee joint biomechanics and neuromuscular control during gait before and after total knee arthroplasty are sex-specific.

PubMed

Astephen Wilson, Janie L; Dunbar, Michael J; Hubley-Kozey, Cheryl L

2015-01-01

The future of total knee arthroplasty (TKA) surgery will involve planning that incorporates more patient-specific characteristics. Despite known biological, morphological, and functional differences between men and women, there has been little investigation into knee joint biomechanical and neuromuscular differences between men and women with osteoarthritis, and none that have examined sex-specific biomechanical and neuromuscular responses to TKA surgery. The objective of this study was to examine sex-associated differences in knee kinematics, kinetics and neuromuscular patterns during gait before and after TKA. Fifty-two patients with end-stage knee OA (28 women, 24 men) underwent gait and neuromuscular analysis within the week prior to and one year after surgery. A number of sex-specific differences were identified which suggest a different manifestation of end-stage knee OA between the sexes. Copyright © 2014 Elsevier Inc. All rights reserved.

Targeted metabolomic profiling in rat tissues reveals sex differences.

PubMed

Ruoppolo, Margherita; Caterino, Marianna; Albano, Lucia; Pecce, Rita; Di Girolamo, Maria Grazia; Crisci, Daniela; Costanzo, Michele; Milella, Luigi; Franconi, Flavia; Campesi, Ilaria

2018-03-16

Sex differences affect several diseases and are organ-and parameter-specific. In humans and animals, sex differences also influence the metabolism and homeostasis of amino acids and fatty acids, which are linked to the onset of diseases. Thus, the use of targeted metabolite profiles in tissues represents a powerful approach to examine the intermediary metabolism and evidence for any sex differences. To clarify the sex-specific activities of liver, heart and kidney tissues, we used targeted metabolomics, linear discriminant analysis (LDA), principal component analysis (PCA), cluster analysis and linear correlation models to evaluate sex and organ-specific differences in amino acids, free carnitine and acylcarnitine levels in male and female Sprague-Dawley rats. Several intra-sex differences affect tissues, indicating that metabolite profiles in rat hearts, livers and kidneys are organ-dependent. Amino acids and carnitine levels in rat hearts, livers and kidneys are affected by sex: male and female hearts show the greatest sexual dimorphism, both qualitatively and quantitatively. Finally, multivariate analysis confirmed the influence of sex on the metabolomics profiling. Our data demonstrate that the metabolomics approach together with a multivariate approach can capture the dynamics of physiological and pathological states, which are essential for explaining the basis of the sex differences observed in physiological and pathological conditions.

Cardiovascular biomarkers and sex: the case for women.

PubMed

Daniels, Lori B; Maisel, Alan S

2015-10-01

Measurement of biomarkers is a critical component of cardiovascular care. Women and men differ in their cardiac physiology and manifestations of cardiovascular disease. Although most cardiovascular biomarkers are used by clinicians without taking sex into account, sex-specific differences in biomarkers clearly exist. Baseline concentrations of many biomarkers (including cardiac troponin, natriuretic peptides, galectin-3, and soluble ST2) differ in men versus women, but these sex-specific differences do not generally translate into a need for differential sex-based cut-off points. Furthermore, most biomarkers are similarly diagnostic and prognostic, regardless of sex. Two potential exceptions are cardiac troponins measured by high-sensitivity assay, and proneurotensin. Troponin levels are lower in women than in men and, with the use of high-sensitivity assays, sex-specific cut-off points might improve the diagnosis of myocardial infarction. Proneurotensin is a novel biomarker that was found to be predictive of incident cardiovascular disease in women, but not men, and was also predictive of incident breast cancer. If confirmed, proneurotensin might be a unique biomarker of disease risk in women. With any biomarker, an understanding of sex-specific differences might improve its use and might also lead to an enhanced understanding of the physiological differences between the hearts of men and women.

Sex Hormones and Sex Chromosomes Cause Sex Differences in the Development of Cardiovascular Diseases.

PubMed

Arnold, Arthur P; Cassis, Lisa A; Eghbali, Mansoureh; Reue, Karen; Sandberg, Kathryn

2017-05-01

This review summarizes recent evidence concerning hormonal and sex chromosome effects in obesity, atherosclerosis, aneurysms, ischemia/reperfusion injury, and hypertension. Cardiovascular diseases occur and progress differently in the 2 sexes, because biological factors differing between the sexes have sex-specific protective and harmful effects. By comparing the 2 sexes directly, and breaking down sex into its component parts, one can discover sex-biasing protective mechanisms that might be targeted in the clinic. Gonadal hormones, especially estrogens and androgens, have long been found to account for some sex differences in cardiovascular diseases, and molecular mechanisms mediating these effects have recently been elucidated. More recently, the inherent sexual inequalities in effects of sex chromosome genes have also been implicated as contributors in animal models of cardiovascular diseases, especially a deleterious effect of the second X chromosome found in females but not in males. Hormonal and sex chromosome mechanisms interact in the sex-specific control of certain diseases, sometimes by opposing the action of the other. © 2017 American Heart Association, Inc.

Sex-specific evolution during the diversification of live-bearing fishes.

PubMed

Culumber, Zachary W; Tobler, Michael

2017-08-01

Natural selection is often assumed to drive parallel functional diversification of the sexes. But males and females exhibit fundamental differences in their biology, and it remains largely unknown how sex differences affect macroevolutionary patterns. On microevolutionary scales, we understand how natural and sexual selection interact to give rise to sex-specific evolution during phenotypic diversification and speciation. Here we show that ignoring sex-specific patterns of functional trait evolution misrepresents the macroevolutionary adaptive landscape and evolutionary rates for 112 species of live-bearing fishes (Poeciliidae). Males and females of the same species evolve in different adaptive landscapes. Major axes of female morphology were correlated with environmental variables but not reproductive investment, while male morphological variation was primarily associated with sexual selection. Despite the importance of both natural and sexual selection in shaping sex-specific phenotypic diversification, species diversification was overwhelmingly associated with ecological divergence. Hence, the inter-predictability of mechanisms of phenotypic and species diversification may be limited in many systems. These results underscore the importance of explicitly addressing sex-specific diversification in empirical and theoretical frameworks of evolutionary radiations to elucidate the roles of different sources of selection and constraint.

The influences of sex and posture on joint energetics during drop landings.

PubMed

Norcross, M F; Shultz, S J; Weinhold, P S; Lewek, M D; Padua, D A; Blackburn, J T

2015-04-01

Previous observations suggest that females utilize a more erect initial landing posture than males with sex differences in landing posture possibly related to sex-specific energy absorption (EA) strategies. However, sex-specific EA strategies have only been observed when accompanied by sex differences in initial landing posture. This study (a) investigated the potential existence of sex-specific EA strategies; and (b) determined the influences of sex and initial landing posture on the biomechanical determinants of EA. The landing biomechanics of 80 subjects were recorded during drop landings in Preferred, Flexed, and Erect conditions. No sex differences in joint EA were identified after controlling for initial landing posture. Males and females exhibited greater ankle EA during Erect vs Flexed landings with this increase driven by 12% greater ankle velocity, but no change in ankle extensor moment. No differences in hip and knee EA were observed between conditions. However, to achieve similar knee EA, subjects used 7% greater mean knee extensor moment but 9% less knee angular velocity during Flexed landings. The results suggest that sex-specific EA strategies do not exist, and that the magnitude of knee joint EA can be maintained by modulating the relative contributions of joint moment and angular velocity to EA. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sex Differences in Mental and Behavioral Traits.

ERIC Educational Resources Information Center

Garai, Josef E.; Scheinfeld, Amram

1968-01-01

This review of research conducted on sex differences attempts to answer the following questions: (1) Do the sexes differ in their basic capacities for specific types of mental performance and occupational achievement? (2) If such differences exist, to what extent are they genetically determined? (3) Are sex differences in abilities, interests, and…

Sex Differences in Task Distribution and Task Exposures among Danish House Painters: An Observational Study Combining Questionnaire Data with Biomechanical Measurements

PubMed Central

Heilskov-Hansen, Thomas; Wulff Svendsen, Susanne; Frølund Thomsen, Jane; Mikkelsen, Sigurd; Hansson, Gert-Åke

2014-01-01

Objectives Sex differences in occupational biomechanical exposures may be part of the explanation why musculoskeletal complaints and disorders tend to be more common among women than among men. We aimed to determine possible sex differences in task distribution and task-specific postures and movements of the upper extremities among Danish house painters, and to establish sex-specific task exposure matrices. Methods To obtain task distributions, we sent out a questionnaire to all members of the Painters' Union in Denmark (N = 9364), of whom 53% responded. Respondents reported their task distributions in a typical week. To obtain task exposures, postures and movements were measured in 25 male and 25 female house painters for one whole working day per person. We used goniometers on the wrists, and inclinometers on the forehead and the upper arms. Participants filled in a logbook allowing task-specific exposures to be identified. Percentiles and % time with non-neutral postures were used to characterise postures. Velocity, range of motion, repetitiveness, and variation were used as measures of movement. Cochran-Mantel-Haenszel statistics and unpaired double-sided t-tests with post-hoc Bonferroni correction were used to evaluate sex differences. Results Statistically significant (p<0.05) sex differences were revealed in task proportions, but the proportions differed by less than 4%. For task exposures, no statistically significant sex differences were found. Conclusions Only minor sex differences were found in task distribution and task exposures regarding postures and movements among Danish house painters. Sex-specific task exposure matrices were established. PMID:25365301

A General Theory of Sexual Differentiation

PubMed Central

Arnold, Arthur P.

2016-01-01

A general theory of mammalian sexual differentiation is proposed. All biological sex differences are the result of the inequality in effects of the sex chromosomes, which are the only factors that differ in XX vs. XY zygotes. This inequality leads to male-specific effects of the Y chromosome, including expression of the testis-determining gene Sry that causes differentiation of testes. Thus, Sry sets up lifelong sex differences in effects of gonadal hormones. Y genes also act outside of the gonads to cause male-specific effects. Differences in the number of X chromosomes between XX and XY cells causes sex differences in expression (1) of Xist, (2) of X genes that escape inactivation, and (2) of parentally imprinted X genes. Sex differences in phenotype are ultimately the result of multiple, independent sex-biasing factors, hormonal and sex chromosomal. These factors act in parallel and in combination to induce sex differences. They can also can offset each other to reduce sex differences. Other mechanisms, operating at the level of populations, cause groups of males to differ on average from groups of females. The theory has advantages for directing attention to inherent sex-biasing factors that operate in many tissues to cause sex differences, to cause sex-biased protection from disease, and to frame questions for further study. PMID:27870435

A general theory of sexual differentiation.

PubMed

Arnold, Arthur P

2017-01-02

A general theory of mammalian sexual differentiation is proposed. All biological sex differences are the result of the inequality in effects of the sex chromosomes, which are the only factors that differ in XX vs. XY zygotes. This inequality leads to male-specific effects of the Y chromosome, including expression of the testis-determining gene Sry that causes differentiation of testes. Thus, Sry sets up lifelong sex differences in effects of gonadal hormones. Y genes also act outside of the gonads to cause male-specific effects. Differences in the number of X chromosomes between XX and XY cells cause sex differences in expression (1) of Xist, (2) of X genes that escape inactivation, and (3) of parentally imprinted X genes. Sex differences in phenotype are ultimately the result of multiple, independent sex-biasing factors, hormonal and sex chromosomal. These factors act in parallel and in combination to induce sex differences. They also can offset each other to reduce sex differences. Other mechanisms, operating at the level of populations, cause groups of males to differ on average from groups of females. The theory frames questions for further study, and directs attention to inherent sex-biasing factors that operate in many tissues to cause sex differences, and to cause sex-biased protection from disease. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Deletion of Fmr1 results in sex-specific changes in behavior.

PubMed

Nolan, Suzanne O; Reynolds, Conner D; Smith, Gregory D; Holley, Andrew J; Escobar, Brianna; Chandler, Matthew A; Volquardsen, Megan; Jefferson, Taylor; Pandian, Ashvini; Smith, Tileena; Huebschman, Jessica; Lugo, Joaquin N

2017-10-01

In this study, we used a systemic Fmr1 knockout in order to investigate both genotype- and sex-specific differences across multiple measures of sociability, repetitive behaviors, activity levels, anxiety, and fear-related learning and memory. Fragile X syndrome is the most common monogenic cause of intellectual disability and autism. Few studies to date have examined sex differences in a mouse model of Fragile X syndrome, though clinical data support the idea of differences in both overall prevalence and phenotype between the sexes. Using wild-type and systemic homozygous Fmr1 knockout mice, we assessed a variety of behavioral paradigms in adult animals, including the open field test, elevated plus maze, nose-poke assay, accelerating rotarod, social partition task, three-chambered social task, and two different fear conditioning paradigms. Tests were ordered such that the most invasive tests were performed last in the sequence, and testing paradigms for similar behaviors were performed in separate cohorts to minimize testing effects. Our results indicate several sex-specific changes in Fmr1 knockout mice, including male-specific increases in activity levels, and female-specific increases in repetitive behaviors on both the nose-poke assay and motor coordination on the accelerating rotarod task. The results also indicated that Fmr1 deletion results in deficits in fear learning and memory across both sexes, and no changes in social behavior across two tasks. These findings highlight the importance of including female subjects in preclinical studies, as simply studying the impact of genetic mutations in males does not yield a complete picture of the phenotype. Further research should explore these marked phenotypic differences among the sexes. Moreover, given that treatment strategies are typically equivalent between the sexes, the results highlight a potential need for sex-specific therapeutics.

Sex Role Typing in the Preschool Years: An Overview.

ERIC Educational Resources Information Center

Vroegh, Karen; Handrich, Millicent

Sex role typing in the preschool child is the subject of this research report. Specific topics considered are sex differences, awareness of sex differences, sex role preferences, parent preferences, sex role identification, and family variables related to sex role typing. This summary of research studies in the field reports experimental and…

Anthropogenic impacts on Costa Rican bat parasitism are sex specific.

PubMed

Frank, Hannah K; Mendenhall, Chase D; Judson, Seth D; Daily, Gretchen C; Hadly, Elizabeth A

2016-07-01

While anthropogenic impacts on parasitism of wildlife are receiving growing attention, whether these impacts vary in a sex-specific manner remains little explored. Differences between the sexes in the effect of parasites, linked to anthropogenic activity, could lead to uneven sex ratios and higher population endangerment. We sampled 1108 individual bats in 18 different sites across an agricultural mosaic landscape in southern Costa Rica to investigate the relationships between anthropogenic impacts (deforestation and reductions in host species richness) and bat fly ectoparasitism of 35 species of Neotropical bats. Although female and male bat assemblages were similar across the deforestation gradient, bat fly assemblages tracked their hosts closely only on female bats. We found that in female hosts, parasite abundance per bat decreased with increasing bat species richness, while in male hosts, parasite abundance increased. We hypothesize the differences in the parasite-disturbance relationship are due to differences in roosting behavior between the sexes. We report a sex-specific parasite-disturbance relationship and argue that sex differences in anthropogenic impacts on wildlife parasitism could impact long-term population health and survival.

Sex linkage, sex-specific selection, and the role of recombination in the evolution of sexually dimorphic gene expression.

PubMed

Connallon, Tim; Clark, Andrew G

2010-12-01

Sex-biased genes--genes that are differentially expressed within males and females--are nonrandomly distributed across animal genomes, with sex chromosomes and autosomes often carrying markedly different concentrations of male- and female-biased genes. These linkage patterns are often gene- and lineage-dependent, differing between functional genetic categories and between species. Although sex-specific selection is often hypothesized to shape the evolution of sex-linked and autosomal gene content, population genetics theory has yet to account for many of the gene- and lineage-specific idiosyncrasies emerging from the empirical literature. With the goal of improving the connection between evolutionary theory and a rapidly growing body of genome-wide empirical studies, we extend previous population genetics theory of sex-specific selection by developing and analyzing a biologically informed model that incorporates sex linkage, pleiotropy, recombination, and epistasis, factors that are likely to vary between genes and between species. Our results demonstrate that sex-specific selection and sex-specific recombination rates can generate, and are compatible with, the gene- and species-specific linkage patterns reported in the genomics literature. The theory suggests that sexual selection may strongly influence the architectures of animal genomes, as well as the chromosomal distribution of fixed substitutions underlying sexually dimorphic traits. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

Sex-specific lifespan and its evolution in nematodes.

PubMed

Ancell, Henry; Pires-daSilva, Andre

2017-10-01

Differences between sexes of the same species in lifespan and aging rate are widespread. While the proximal and evolutionary causes of aging are well researched, the factors that contribute to sex differences in these traits have been less studied. The striking diversity of nematodes provides ample opportunity to study variation in sex-specific lifespan patterns associated with shifts in life history and mating strategy. Although the plasticity of these sex differences will make it challenging to generalize from invertebrate to vertebrate systems, studies in nematodes have enabled empirical evaluation of predictions regarding the evolution of lifespan. These studies have highlighted how natural and sexual selection can generate divergent patterns of lifespan if the sexes are subject to different rates or sources of mortality, or if trade-offs between complex traits and longevity are resolved differently in each sex. Here, we integrate evidence derived mainly from nematodes that addresses the molecular and evolutionary basis of sex-specific aging and lifespan. Ultimately, we hope to generate a clearer picture of current knowledge in this area, and also highlight the limitations of our understanding. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Category-specificity in sexual interest in gay men and lesbians.

PubMed

Rullo, Jordan E; Strassberg, Donald S; Israel, Esther

2010-08-01

The present study assessed the category-specificity of sexual interest of gay men and lesbians toward an understanding of the possible interaction of sex and sexual orientation that may exist in this phenomenon. Utilizing viewing time as a measure of sexual interest, we had participants (N = 99) rate the sexual appeal of sexually provocative pictures while the amount of time spent viewing each picture was inconspicuously measured. As hypothesized, same-sex oriented individuals demonstrated a category-specific pattern of sexual interest. That is, gay men and lesbians (1) viewed preferred sex pictures (i.e., of same sex) significantly longer than nonpreferred sex pictures (i.e., of opposite sex) and (2) rated preferred sex pictures as significantly more sexually appealing than nonpreferred sex pictures. Additionally, the difference in viewing times between preferred and nonpreferred sexual stimuli was not significantly different for gay men and lesbians, suggesting that lesbians are as category-specific as gay men. The implications of these findings are discussed.

Age and sex differences in oxytocin and vasopressin V1a receptor binding densities in the rat brain: focus on the social decision-making network.

PubMed

Smith, Caroline J W; Poehlmann, Max L; Li, Sara; Ratnaseelan, Aarane M; Bredewold, Remco; Veenema, Alexa H

2017-03-01

Oxytocin (OT) and vasopressin (AVP) regulate various social behaviors via activation of the OT receptor (OTR) and the AVP V1a receptor (V1aR) in the brain. Social behavior often differs across development and between the sexes, yet our understanding of age and sex differences in brain OTR and V1aR binding remains incomplete. Here, we provide an extensive analysis of OTR and V1aR binding density throughout the brain in juvenile and adult male and female rats, with a focus on regions within the social decision-making network. OTR and V1aR binding density were higher in juveniles than in adults in regions associated with reward and socio-spatial memory and higher in adults than in juveniles in key regions of the social decision-making network and in cortical regions. We discuss possible implications of these shifts in OTR and V1aR binding density for the age-specific regulation of social behavior. Furthermore, sex differences in OTR and V1aR binding density were less numerous than age differences. The direction of these sex differences was region-specific for OTR but consistently higher in females than in males for V1aR. Finally, almost all sex differences in OTR and V1aR binding density were already present in juveniles and occurred in regions with denser binding in adults compared to juveniles. Possible implications of these sex differences for the sex-specific regulation of behavior, as well potential underlying mechanisms, are discussed. Overall, these findings provide an important framework for testing age- and sex-specific roles of OTR and V1aR in the regulation of social behavior.

76 FR 78670 - Draft Guidance for Industry and Food and Drug Administration Staff; Evaluation of Sex Differences...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-19

...] Draft Guidance for Industry and Food and Drug Administration Staff; Evaluation of Sex Differences in... entitled ``Evaluation of Sex Differences in Medical Device Clinical Studies.'' This document provides guidance on the study and evaluation of sex differences in medical device clinical trials, with a specific...

The Genetics of Sex Differences in Brain and Behavior

PubMed Central

Ngun, Tuck C; Ghahramani, Negar; Sánchez, Francisco J.; Bocklandt, Sven; Vilain, Eric

2010-01-01

Biological differences between men and women contribute to many sex-specific illnesses and disorders. Historically, it was argued that such differences were largely, if not exclusively, due to gonadal hormone secretions. However, emerging research has shown that some differences are mediated by mechanisms other than the action of these hormone secretions and in particular by products of genes located on the X and Y chromosomes, which we refer to as direct genetic effects. This paper reviews the evidence for direct genetic effects in behavioral and brain sex differences. We highlight the `four core genotypes' model and sex differences in the midbrain dopaminergic system, specifically focusing on the role of Sry. We also discuss novel research being done on unique populations including people attracted to the same sex and people with a cross-gender identity. As science continues to advance our understanding of biological sex differences, a new field is emerging that is aimed at better addressing the needs of both sexes: gender-based biology and medicine. Ultimately, the study of the biological basis for sex differences will improve healthcare for both men and women. PMID:20951723

Segregation or aggregation? Sex-specific patterns in the seasonal occurrence of white sharks Carcharodon carcharias at the Neptune Islands, South Australia.

PubMed

Bruce, B; Bradford, R

2015-12-01

The seasonal patterns of occurrence of male and female white sharks Carcharodon carcharias at the Neptune Islands in South Australia were reviewed. Analyses of a 14 year data series indicate that females seasonally aggregate in late autumn and winter coinciding with the maximum in-water availability of lactating female long-nose fur seals and seal pups. During this period, observed male:female sex ratios were similar; whereas during late spring and summer, males continued to visit, but females were rarely recorded. There was no evidence for segregation by sex or size at the Neptunes, but the highly focused seasonal pattern of occurrence of females compared with the year-round records of males suggests that there are likely to be differences between the sexes in overall distribution and movement patterns across southern Australia. It is suggested that foraging strategies and prey selection differ between sexes in C. carcharias across the life-history stages represented and that sex-specific foraging strategies may play an important role in structuring movement patterns and the sex ratios observed at such aggregation sites. Differences between sexes in distribution, movement patterns and foraging strategies are likely to have implications for modelling the consequences of fisheries by-catch between regions or jurisdictions and other spatially or temporally discrete anthropogenic effects on C. carcharias populations. Such differences urge for caution when estimating the size of C. carcharias populations based on observations at pinniped colonies due to the likelihood of sex-specific differences in movements and patterns of residency. These differences also suggest a need to account for sex-specific movement patterns and distribution in population and movement models as well as under conservation actions. © 2015 The Fisheries Society of the British Isles.

Comparative Transcriptomics in East African Cichlids Reveals Sex- and Species-Specific Expression and New Candidates for Sex Differentiation in Fishes

PubMed Central

Böhne, Astrid; Sengstag, Thierry; Salzburger, Walter

2014-01-01

Males and females of the same species differ largely in gene expression, which accounts for most of the morphological and physiological differences and sex-specific phenotypes. Here, we analyzed sex-specific gene expression in the brain and the gonads of cichlid fishes from Lake Tanganyika belonging to four different lineages, so-called tribes (Eretmodini, Ectodini, Haplochromini, and Lamprologini), using the outgroup Nile tilapia (Oreochromis niloticus) as reference. The comparison between male and female brains revealed few differences between the sexes, consistent in all investigated species. The gonads, on the other hand, showed a large fraction of differentially expressed transcripts with the majority of them showing the same direction of expression in all four species. All here-studied cichlids, especially the three investigated mouth-breeding species, showed a trend toward more male- than female-biased transcripts. Transcripts, which were female-biased in expression in all four species, were overrepresented on linkage group (LG)1 in the reference genome and common male-biased transcripts showed accumulation on LG23, the presumable sex chromosomes of the Nile tilapia. Sex-specific transcripts contained candidate genes for sex determination and differentiation in fishes, especially members of the transforming growth factor-β-superfamily and the Wnt-pathway and also prominent members of the sox-, dm-domain-, and high mobility group-box families. We further confirmed our previous finding on species/lineage-specific gene expression shifts in the sex steroid pathway, including synthesizing enzymes as the aromatase cyp19a1 and estrogen and androgen receptors. PMID:25364805

Sex-specific movements in postfledging juvenile Ovenbirds (Seiurus aurocapilla)

Treesearch

Julianna M. A. Jenkins; Mikenzie Hart; Lori S. Eggert; John Faaborg

2017-01-01

Understanding sex-specific differences in behavior and survival is essential for informative population modeling and evolutionary biology in animal populations. Uneven sex ratios are common in many migrant passerine species; however, the underlying mechanisms remain unclear. We used molecular sex determination, nest monitoring, and radio telemetry of fledgling...

Sex differences in drug addiction and response to exercise intervention: from human to animal studies

PubMed Central

Zhou, Yuehui; Zhao, Min; Zhou, Chenglin; Li, Rena

2015-01-01

Accumulated research supports the idea that exercise could be an option of potential prevention and treatment for drug addiction. During the past few years, there has been increased interest in investigating of sex differences in exercise and drug addiction. This demonstrates that sex-specific exercise intervention strategies may be important for preventing and treating drug addiction in men and women. However, little is known about how and why sex differences are found when doing exercise-induced interventions for drug addiction. In this review, we included both animal and human that pulled subjects from a varied age demographic, as well as neurobiological mechanisms that may highlight the sex-related differences in these potential to assess the impact of sex-specific roles in drug addiction and exercise therapies. PMID:26182835

Sex differences in patterns of genital sexual arousal: measurement artifacts or true phenomena?

PubMed

Suschinsky, Kelly D; Lalumière, Martin L; Chivers, Meredith L

2009-08-01

Sex differences in patterns of sexual arousal have been reported recently. Men's genital arousal is typically more category-specific than women's, such that men experience their greatest genital arousal to stimuli depicting their preferred sex partners whereas women experience significant genital arousal to stimuli depicting both their preferred and non-preferred sex partners. In addition, men's genital and subjective sexual arousal patterns are more concordant than women's: The correlation between genital and subjective sexual arousal is much larger in men than in women. These sex differences could be due to low response-specificity in the measurement of genital arousal in women. The most commonly used measure of female sexual arousal, vaginal photoplethysmography, has not been fully validated and may not measure sexual arousal specifically. A total of 20 men and 20 women were presented with various sexual and non-sexual emotionally laden short film clips while their genital and subjective sexual arousal were measured. Results suggest that vaginal photoplethysmography is a measure of sexual arousal exclusively. Women's genital responses were highest during sexual stimuli and absent during all non-sexual stimuli. Sex differences in degree of category-specificity and concordance were replicated: Men's genital responses were more category-specific than women's and men's genital and subjective sexual arousal were more strongly correlated than women's. The results from the current study support the continued use of vaginal photoplethysmography in investigating sex differences in patterns of sexual arousal.

The neuroendocrine basis of sex differences in epilepsy.

PubMed

Reddy, Doodipala Samba

2017-01-01

Epilepsy affects people of all ages and both genders. Sex differences are well known in epilepsy. Seizure susceptibility and the incidence of epilepsy are generally higher in men than women. In addition, there are gender-specific epilepsies such as catamenial epilepsy, a neuroendocrine condition in which seizures are most often clustered around the perimenstrual or periovulatory period in adult women with epilepsy. Changes in seizure sensitivity are also evident at puberty, pregnancy, and menopause. Sex differences in seizure susceptibility and resistance to antiseizure drugs can be studied in experimental models. An improved understanding of the neuroendocrine basis of sex differences or resistance to protective drugs is essential to develop targeted therapies for sex-specific seizure conditions. This article provides a brief overview of the current status of sex differences in seizure susceptibility and the potential mechanisms underlying the gender differences in seizure sensitivity. Copyright © 2016. Published by Elsevier Inc.

The neuropsychology of sex offenders: a meta-analysis.

PubMed

Joyal, Christian C; Beaulieu-Plante, Jolyane; de Chantérac, Antoine

2014-04-01

Typically, neuropsychological studies of sex offenders have grouped together different types of individuals and different types of measures. This is why results have tended to be nonspecific and divergent across studies. Against this background, the authors undertook a review of the literature regarding the neuropsychology of sex offenders, taking into account subgroups based on criminological theories. They also conducted a meta-analysis of the data to demonstrate the cognitive heterogeneity of sex offenders statistically. Their main objective was to test the hypothesis to the effect that the neuropsychological deficits of sex offenders are not broad and generalized compared with specific subgroups of participants based on specific measures. In all, 23 neuropsychological studies reporting data on 1,756 participants were taken into consideration. As expected, a highly significant, broad, and heterogeneous overall effect size was found. Taking subgroups of participants and specific cognitive measures into account significantly improved homogeneity. Sex offenders against children tended to obtain lower scores than did sex offenders against adults on higher order executive functions, whereas sex offenders against adults tended to obtain results similar to those of non-sex offenders, with lower scores in verbal fluency and inhibition. However, it is concluded that neuropsychological data on sex offenders are still too scarce to confirm these trends or to test more precise hypotheses. For greater clinical relevance, future neuropsychological studies should consider specific subgroups of participants and measures to verify the presence of different cognitive profiles.

Sex and the development of Alzheimer’s disease

PubMed Central

Pike, Christian J.

2016-01-01

Men and women exhibit differences in the development and progression of Alzheimer’s disease (AD). The factors underlying the sex differences in AD are not well understood. This review emphasizes the contributions of sex steroid hormones to the relationship between sex and AD. In women, events that decrease lifetime exposure to estrogens are generally associated with increased AD risk, whereas estrogen-based hormone therapy administered near the time of menopause may reduce AD risk. In men, estrogens do not exhibit age-related reduction and are not significantly associated with AD risk. Rather, normal age-related depletions of testosterone in plasma and brain predict enhanced vulnerability to AD. Both estrogens and androgens exert numerous protective actions in the adult brain that increase neural functioning and resilience as well as specifically attenuate multiple aspects of AD-related neuropathology. Aging diminishes the activational effects of sex hormones in sex-specific manners, which is hypothesized to contribute to the relationship between aging and AD. Sex steroid hormones may also drive sex differences in AD through their organizational effects during developmental sexual differentiation of the brain. Specifically, sex hormone actions during early development may confer inherent vulnerability of the female brain to development of AD in advanced age. The combined effects of organizational and activational effects of sex steroids yield distinct sex differences in AD pathogenesis, a significant variable that must be more rigorously considered in future research. PMID:27870425

Sex differences in cognitive impairment and Alzheimer's disease.

PubMed

Li, Rena; Singh, Meharvan

2014-08-01

Studies have shown differences in specific cognitive ability domains and risk of Alzheimer's disease between the men and women at later age. However it is important to know that sex differences in cognitive function during adulthood may have their basis in both organizational effects, i.e., occurring as early as during the neuronal development period, as well as in activational effects, where the influence of the sex steroids influence brain function in adulthood. Further, the rate of cognitive decline with aging is also different between the sexes. Understanding the biology of sex differences in cognitive function will not only provide insight into Alzheimer's disease prevention, but also is integral to the development of personalized, gender-specific medicine. This review draws on epidemiological, translational, clinical, and basic science studies to assess the impact of sex differences in cognitive function from young to old, and examines the effects of sex hormone treatments on Alzheimer's disease in men and women. Copyright © 2014 Elsevier Inc. All rights reserved.

Sex Differences in Cognitive Impairment and Alzheimer’s Disease

PubMed Central

Li, Rena; Singh, Meharvan

2014-01-01

Studies have shown differences in specific cognitive ability domains and risk of Alzheimer’s disease between the men and women at later age. However it is important to know that sex differences in cognitive function during adulthood may have their basis in both organizational effects, i.e., occurring as early as during the neuronal development period, as well as in activational effects, where the influence of the sex steroids influence brain function in adulthood. Further, the rate of cognitive decline with aging is also different between the sexes. Understanding the biology of sex differences in cognitive function will not only provide insight into Alzheimer’s disease prevention, but also is integral to the development of personalized, gender-specific medicine. This review draws on epidemiological, translational, clinical, and basic science studies to assess the impact of sex differences in cognitive function from young to old, and examines the effects of sex hormone treatments on Alzheimer’s disease in men and women. PMID:24434111

Sex differences in lizard escape decisions vary with latitude, but not sexual dimorphism.

PubMed

Samia, Diogo S M; Møller, Anders Pape; Blumstein, Daniel T; Stankowich, Theodore; Cooper, William E

2015-04-22

Sexual selection is a powerful evolutionary mechanism that has shaped the physiology, behaviour and morphology of the sexes to the extent that it can reduce viability while promoting traits that enhance reproductive success. Predation is one of the underlying mechanisms accounting for viability costs of sexual displays. Therefore, we should expect that individuals of the two sexes adjust their anti-predator behaviour in response to changes in predation risk. We conducted a meta-analysis of 28 studies (42 species) of sex differences in risk-taking behaviour in lizards and tested whether these differences could be explained by sexual dichromatism, by sexual size dimorphism or by latitude. Latitude was the best predictor of the interspecific heterogeneity in sex-specific behaviour. Males did not change their escape behaviour with latitude, whereas females had increasingly reduced wariness at higher latitudes. We hypothesize that this sex difference in risk-taking behaviour is linked to sex-specific environmental constraints that more strongly affect the reproductive effort of females than males. This novel latitudinal effect on sex-specific anti-predator behaviour has important implications for responses to climate change and for the relative roles of natural and sexual selection in different species. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

A Novel Method for Assessing Sex-Specific and Genotype-Specific Response to Injury in Astrocyte Culture

PubMed Central

Liu, Mingyue; Oyarzabal, Esteban; Yang, Rui; Murphy, Stephanie J; Hurn, Patricia D.

2008-01-01

Female astrocytes sustain less cell death from oxygen-glucose deprivation (OGD) than male astrocytes. Arimidex, an aromatase inhibitor, abolishes these sex differences. To verify sex-dependent differences in P450 aromatase function in astrocyte cell death following OGD, we developed a novel method that uses sex-specific and genotype-specific single pup primary astrocyte cultures from wild-type (WT) and aromatase-knockout (ArKO) mice. After determining sex by external and internal examination as well as PCR and genotype by PCR amplification of tail cDNA, we established cultures from 1−3 day-old male and female, WT and ArKO mice pups and grew them to confluence in estrogen-free media. Cell death was measured by lactate dehydrogenase (LDH) assay. Our study shows that, while WT female astrocytes are more resistant to OGD than WT male cells, sex differences disappear in ArKO cells. Cell death is significantly increased in ArKO compared to WT in female astrocytes but not male cells. Therefore, P450 aromatase appears to be essential in endogenous neuroprotection in females, and this finding may have clinical implications. This innovative technique may also be applied to other in vitro studies of sex-related functional differences. PMID:18436308

Review of Research--Sex Differences in Intellectual Functioning: Myth or Reality.

ERIC Educational Resources Information Center

Glickman, Judith R.

Sex difference research has been plagued with a myriad of problems,. Specifically, intelligence testing, if dependent on measurement of spatial or verbal proficiency, may not be an accurate indicator of native ability. Similarly, infrequent replication of studies, studies that only include subjects of one sex yet imply sex differences, and poor…

Role of Microbiota in Sexually Dimorphic Immunity.

PubMed

Elderman, Marlies; de Vos, Paul; Faas, Marijke

2018-01-01

Sex differences in peripheral immune responses are well recognized. This is associated with sex differences in many immunological diseases. As the intestinal microbiota is known to influence the immune system, such sex differences in immune responses may be a consequence of sex-specific microbiota. Therefore, this mini-review discusses sex differences in intestinal microbiota and the possible role of microbiota in shaping sexually dimorphic immunity. Sex differences in microbiota composition are clearly found in mice studies and also in human studies. However, the lack of standardization in human studies may mask the sexual dimorphism in microbiota composition in human studies, since many factors such as age, genetic background, BMI, diet, and sex hormones appear to interfere with the sexual dimorphism in microbiota composition. Only a few mice studies found that differences in gut microbiota composition are causative for some aspects of sexually dimorphic immunity. Therefore, future studies should focus on a causal relationship between sexually dimorphic immunity and microbiota, considering the abovementioned interfering confounding factors. This would benefit the development of more sex-specific effective treatment options for immunological diseases.

Host Sexual Dimorphism and Parasite Adaptation

PubMed Central

Duneau, David; Ebert, Dieter

2012-01-01

In species with separate sexes, parasite prevalence and disease expression is often different between males and females. This effect has mainly been attributed to sex differences in host traits, such as immune response. Here, we make the case for how properties of the parasites themselves can also matter. Specifically, we suggest that differences between host sexes in many different traits, such as morphology and hormone levels, can impose selection on parasites. This selection can eventually lead to parasite adaptations specific to the host sex more commonly encountered, or to differential expression of parasite traits depending on which host sex they find themselves in. Parasites adapted to the sex of the host in this way can contribute to differences between males and females in disease prevalence and expression. Considering those possibilities can help shed light on host–parasite interactions, and impact epidemiological and medical science. PMID:22389630

Sex differences in drug addiction and response to exercise intervention: From human to animal studies.

PubMed

Zhou, Yuehui; Zhao, Min; Zhou, Chenglin; Li, Rena

2016-01-01

Accumulated research supports the idea that exercise could be an option of potential prevention and treatment for drug addiction. During the past few years, there has been increased interest in investigating of sex differences in exercise and drug addiction. This demonstrates that sex-specific exercise intervention strategies may be important for preventing and treating drug addiction in men and women. However, little is known about how and why sex differences are found when doing exercise-induced interventions for drug addiction. In this review, we included both animal and human that pulled subjects from a varied age demographic, as well as neurobiological mechanisms that may highlight the sex-related differences in these potential to assess the impact of sex-specific roles in drug addiction and exercise therapies. Copyright © 2015 Elsevier Inc. All rights reserved.

Increased fat deposition in injured skeletal muscle is regulated by sex-specific hormones

PubMed Central

McHale, Matthew J.; Sarwar, Zaheer U.; Cardenas, Damon P.; Porter, Laurel; Salinas, Anna S.; Michalek, Joel E.; McManus, Linda M.

2012-01-01

Sex differences in skeletal muscle regeneration are controversial; comparisons of regenerative events between sexes have not been rigorously defined in severe injury models. We comprehensively quantified inflammation and muscle regeneration between sexes and manipulated sex-specific hormones to determine effects on regeneration. Cardiotoxin injury was induced in intact, castrated and ovariectomized female and male mice; ovariectomized mice were replaced with low- or high-dose 17-β estradiol (E2) or progesterone (P4). Extent of injury was comparable between intact mice, but females were more efficient in removal of necrotic debris, despite similar tissue levels of inflammatory cells and chemokines. Myofiber size during regeneration was equivalent between intact mice and after castration or ovariectomy (OVX) but was decreased (P < 0.001) in ovariectomized mice with high-dose E2 replacement. Intermuscular adipocytes were absent in uninjured muscle, whereas adipocyte area was increased among regenerated myofibers in all groups. Interestingly, intermuscular fat was greater (P = 0.03) in intact females at day 14 compared with intact males. Furthermore, castration increased (P = 0.01) and OVX decreased adipocyte accumulation. After OVX, E2, but not P4, replacement decreased (P ≤ 0.03) fat accumulation. In conclusion, sex-dependent differences in regeneration consisted of more efficient removal of necrosis and increased fat deposition in females with similar injury, inflammation, and regenerated myofiber size; high-dose E2 decreased myofiber size and fat deposition. Adipocyte accumulation in regenerating muscle was influenced by sex-specific hormones. Recovery following muscle injury was different between males and females, and sex-specific hormones contributed to these differences, suggesting that sex-specific treatments could be beneficial after injury. PMID:22116509

Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia

PubMed Central

Zemp, Niklaus; Tavares, Raquel; Widmer, Alex

2015-01-01

Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia) displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism. PMID:26448481

Fungal Infection Induces Sex-Specific Transcriptional Changes and Alters Sexual Dimorphism in the Dioecious Plant Silene latifolia.

PubMed

Zemp, Niklaus; Tavares, Raquel; Widmer, Alex

2015-10-01

Sexual dimorphism, including differences in morphology, behavior and physiology between females and males, is widespread in animals and plants and is shaped by gene expression differences between the sexes. Such expression differences may also underlie sex-specific responses of hosts to pathogen infections, most notably when pathogens induce partial sex reversal in infected hosts. The genetic changes associated with sex-specific responses to pathogen infections on the one hand, and sexual dimorphism on the other hand, remain poorly understood. The dioecious White Campion (Silene latifolia) displays sexual dimorphism in floral traits and infection with the smut fungus Micobrotryum lychnidis-dioicae induces a partial sex reversal in females. We find strong sex-specific responses to pathogen infection and reduced sexual dimorphism in infected S. latifolia. This provides a direct link between pathogen-mediated changes in sex-biased gene expression and altered sexual dimorphism in the host. Expression changes following infection affected mainly genes with male-biased expression in healthy plants. In females, these genes were up-regulated, leading to a masculinization of the transcriptome. In contrast, infection in males was associated with down-regulation of these genes, leading to a demasculinization of the transcriptome. To a lesser extent, genes with female-biased expression in healthy plants were also affected in opposite directions in the two sexes. These genes were overall down-regulated in females and up-regulated in males, causing, respectively, a defeminization in infected females and a feminization of the transcriptome in infected males. Our results reveal strong sex-specific responses to pathogen infection in a dioecious plant and provide a link between pathogen-induced changes in sex-biased gene expression and sexual dimorphism.

Genetic and epigenetic factors underlying sex differences in the regulation of gene expression in the brain

PubMed Central

Ratnu, Vikram S.; Emami, Michael R.; Bredy, Timothy W.

2016-01-01

There are inherent biological differences between males and females that contribute to sex differences in brain function and to many sex-specific illnesses and disorders. Traditionally, it has been thought that such differences are largely due to hormonal regulation; however, there are also genetic and epigenetic effects caused by the inheritance and unequal dosage of genes located on the X- and Y-chromosomes. Here we discuss the evidence in favor of a genetic and epigenetic basis for sexually dimorphic behavior, as a consequence of underlying differences in the regulation of genes that drive brain function. A better understanding of sex-specific molecular processes in the brain will provide further insight for the development of novel therapeutic approaches for the treatment of neuropsychiatric disorders characterized by gender/sex differences. PMID:27870402

Differential sex-specific effects of oxygen toxicity in human umbilical vein endothelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yuhao; Lingappan, Krithika

Despite the well-established sex-specific differences in the incidence of bronchopulmonary dysplasia (BPD), the molecular mechanism(s) behind these are not completely understood. Pulmonary angiogenesis is critical for alveolarization and arrest in vascular development adversely affects lung development. Human neonatal umbilical vein endothelial cells (HUVECs) provide a robust in vitro model for the study of endothelial cell physiology and function. Male and Female HUVECs were exposed to room air (21% O{sub 2}, 5% CO{sub 2}) or hyperoxia (95% O{sub 2}, 5% CO{sub 2}) for up to 72 h. Cell viability, proliferation, H{sub 2}O{sub 2} production and angiogenesis were analyzed. Sex-specific differences in the expressionmore » of VEGFR2 and modulation of NF-kappa B pathway were measured. Male HUVECs have decreased survival, greater oxidative stress and impairment in angiogenesis compared to similarly exposed female cells. There is differential expression of VEGFR2 between male and female HUVECs and greater activation of the NF-kappa B pathway in female HUVECs under hyperoxic conditions. The results indicate that sex differences exist between male and female HUVECs in vitro after hyperoxia exposure. Since endothelial dysfunction has a major role in the pathogenesis of BPD, these differences could explain in part the mechanisms behind sex-specific differences in the incidence of this disease. - Highlights: • Cellular sex effects viability and oxidative stress in HUVECs exposed to hyperoxia. • Male HUVECs show greater impairment in angiogenesis compared to female cells. • Sex-specific modulation of VEGFR2 and the NF-kappaB pathway was noted.« less

Sex differences in prevalence and comorbidity of alcohol and drug use disorders: results from wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions.

PubMed

Goldstein, Risë B; Dawson, Deborah A; Chou, S Patricia; Grant, Bridget F

2012-11-01

The present study examined sex differences in lifetime Axis I and II psychiatric comorbidity of DSM-IV alcohol use disorders (AUDs) and drug use disorders (DUDs) among general population U.S. adults. Using data from Waves 1 and 2 of the National Epidemiologic Survey on Alcohol and Related Conditions, Wave 2 lifetime prevalences of each disorder comorbid with alcohol abuse, alcohol dependence, drug abuse, and drug dependence were compared between men and women. Sex-specific associations of alcohol, any drug, and cannabis- and cocaine-specific abuse and dependence with each comorbid disorder were examined using logistic regression, first with adjustment for sociodemographic variables and then with additional adjustment for all other psychiatric disorders. Prevalences of most comorbid disorders differed significantly by sex among respondents with each AUD and DUD. However, after adjustment for sociodemographic characteristics and additional co-occurring psychiatric diagnoses, there were few sex differences in unique comorbid associations of specific AUDs and DUDs with specific psychiatric disorders. Rates of psychiatric disorders comorbid with AUDs and DUDs indicate large burdens of morbidity in both sexes, highlighting the need for careful assessment and appropriate treatment of both substance use and mental health disorders. The unique comorbid associations with AUDs and DUDs identified in this study further indicate the need for prospective etiological research to characterize these associations, their underlying mechanisms, and the possible sex specificity of those mechanisms.

Sex Differences in Prevalence and Comorbidity of Alcohol and Drug Use Disorders: Results From Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions

PubMed Central

Goldstein, Risë B.; Dawson, Deborah A.; Chou, S. Patricia; Grant, Bridget F.

2012-01-01

Objective: The present study examined sex differences in lifetime Axis I and II psychiatric comorbidity of DSM-IV alcohol use disorders (AUDs) and drug use disorders (DUDs) among general population U.S. adults. Method: Using data from Waves 1 and 2 of the National Epidemiologic Survey on Alcohol and Related Conditions, Wave 2 lifetime prevalences of each disorder comorbid with alcohol abuse, alcohol dependence, drug abuse, and drug dependence were compared between men and women. Sex-specific associations of alcohol, any drug, and cannabis- and cocaine-specific abuse and dependence with each comorbid disorder were examined using logistic regression, first with adjustment for sociodemographic variables and then with additional adjustment for all other psychiatric disorders. Results: Prevalences of most comorbid disorders differed significantly by sex among respondents with each AUD and DUD. However, after adjustment for sociodemographic characteristics and additional co-occurring psychiatric diagnoses, there were few sex differences in unique comorbid associations of specific AUDs and DUDs with specific psychiatric disorders. Conclusions: Rates of psychiatric disorders comorbid with AUDs and DUDs indicate large burdens of morbidity in both sexes, highlighting the need for careful assessment and appropriate treatment of both substance use and mental health disorders. The unique comorbid associations with AUDs and DUDs identified in this study further indicate the need for prospective etiological research to characterize these associations, their underlying mechanisms, and the possible sex specificity of those mechanisms. PMID:23036212

Evaluation of the Physiological Challenges in Extreme Environments: Implications for Enhanced Training, Operational Performance and Sex-Specific Responses

DTIC Science & Technology

2016-10-01

Operational Performance and Sex -Specific Responses PRINCIPAL INVESTIGATOR: Brent C. Ruby CONTRACTING ORGANIZATION: The University of Montana System...Environments: Implications for Enhanced Training, Operational Performance and Sex -Specific Responses 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-2-0075...mitochondrial gene responses were not altered by altitude stress. Moreover, there were no differences across sex . While prior research has clearly

Is There a Sex Ratio Difference in the Familial Aggregation of Specific Language Impairment? A Meta-Analysis

ERIC Educational Resources Information Center

Whitehouse, Andrew J. O.

2010-01-01

Purpose: Specific language impairment (SLI) is known to aggregate in families. Debate exists on whether the male sex presents an additional risk for SLI. This meta-analysis examined whether there is a sex ratio difference in the risk for impairment among family members of an SLI proband and whether this is mediated by assessment method (direct…

Accounting for cell lineage and sex effects in the identification of cell-specific DNA methylation using a Bayesian model selection algorithm.

PubMed

White, Nicole; Benton, Miles; Kennedy, Daniel; Fox, Andrew; Griffiths, Lyn; Lea, Rodney; Mengersen, Kerrie

2017-01-01

Cell- and sex-specific differences in DNA methylation are major sources of epigenetic variation in whole blood. Heterogeneity attributable to cell type has motivated the identification of cell-specific methylation at the CpG level, however statistical methods for this purpose have been limited to pairwise comparisons between cell types or between the cell type of interest and whole blood. We developed a Bayesian model selection algorithm for the identification of cell-specific methylation profiles that incorporates knowledge of shared cell lineage and allows for the identification of differential methylation profiles in one or more cell types simultaneously. Under the proposed methodology, sex-specific differences in methylation by cell type are also assessed. Using publicly available, cell-sorted methylation data, we show that 51.3% of female CpG markers and 61.4% of male CpG markers identified were associated with differential methylation in more than one cell type. The impact of cell lineage on differential methylation was also highlighted. An evaluation of sex-specific differences revealed differences in CD56+NK methylation, within both single and multi- cell dependent methylation patterns. Our findings demonstrate the need to account for cell lineage in studies of differential methylation and associated sex effects.

Hunger-dependent and Sex-specific Antipredator Behaviour of Larvae of a Size-dimorphic Mosquito

PubMed Central

Wormington, Jillian; Juliano, Steven

2014-01-01

1. Modification of behaviors in the presence of predators or predation cues is widespread among animals. Costs of a behavioral change in the presence of predators or predation cues depend on fitness effects of lost feeding opportunities and, especially when organisms are sexually dimorphic in size or timing of maturation, these costs are expected to differ between the sexes. 2. Larval Aedes triseriatus (Say) (Diptera: Culicidae) were used to test the hypothesis that behavioral responses of the sexes to predation cues have been selected differently due to different energy demands. 3. Even in the absence of water-borne predation cues, hungry females (the larger sex) spent more time browsing than did males, indicating a difference in energy needs. 4. In the presence of predation cues, well-fed larvae of both sexes reduced their activity more than did hungry larvae, and males shifted away from high-risk behaviors to a greater degree than did females, providing the first evidence of sex-specific antipredator behavior in foraging mosquito larvae. 5. Because sexual size dimorphism is common across taxa, and energetic demands are likely correlated with size dimorphism, this research demonstrates the importance of investigating sex specific behavior and behavioral responses to enemies and cautions against generalizing results between sexes. PMID:25309025

Exploring mechanisms underlying sex-specific differences in mortality of Lake Michigan bloaters

USGS Publications Warehouse

Bunnell, D.B.; Madenjian, C.P.; Rogers, M.W.; Holuszko, J.D.; Begnoche, L.J.

2012-01-01

Sex-specific differences in mortality rates have been observed among freshwater and marine fish taxa, and underlying mechanisms can include sex-specific differences in (1) age at maturity, (2) growth rate, or (3) activity or behavior during the spawning period. We used a long-term (1973–2009) Lake Michigan data set to evaluate whether there were sex-specific differences in catch per unit effort, mortality, age at maturity, and length at age in bloaters Coregonus hoyi. Because bloater population biomass varied 200-fold during the years analyzed, we divided the data into three periods: (1) 1973–1982 (low biomass), (2) 1983–1997 (high biomass), and (3) 1998–2009 (low biomass). Mortality was higher for males than for females in periods 2 and 3; the average instantaneous total mortality rate (Z) over these two periods was 0.71 for males and 0.57 for females. Length at age was slightly greater (2–6%) for females than for males in different age-classes (3–6 years) during each period. Age at maturity was earlier for males than for females in periods 1 and 2, but the mean difference was only 0.2–0.4 years. To test the hypothesis that somatic lipids declined more in males than in females during spawning (perhaps due to increased activity or reduced feeding), we estimated sex-specific percent somatic lipids for fish sampled in 2005–2006 and 2007–2008. During 2005–2006, somatic lipids declined from prespawning to postspawning for males but were unchanged for females. During 2007–2008, however, somatic lipids were unchanged for males, whereas they increased for females. We found that sex-specific differences in Z occurred in the Lake Michigan bloater population, but our hypotheses that sex-specific differences in maturity and growth could explain this pattern were generally unsupported. Our hypothesis that somatic lipids in males declined during spawning at a faster rate than in females will require additional research to clarify its importance.

Sex differences in impulsive action and impulsive choice.

PubMed

Weafer, Jessica; de Wit, Harriet

2014-11-01

Here, we review the evidence for sex differences in behavioral measures of impulsivity for both humans and laboratory animals. We focus on two specific components of impulsivity: impulsive action (i.e., difficulty inhibiting a prepotent response) and impulsive choice (i.e., difficulty delaying gratification). Sex differences appear to exist on these measures, but the direction and magnitude of the differences vary. In laboratory animals, impulsive action is typically greater in males than females, whereas impulsive choice is typically greater in females. In humans, women discount more steeply than men, but sex differences on measures of impulsive action depend on tasks and subject samples. We discuss implications of these findings as they relate to drug addiction. We also point out the major gaps in this research to date, including the lack of studies designed specifically to examine sex differences in behavioral impulsivity, and the lack of consideration of menstrual or estrous phase or sex hormone levels in the studies. © 2013.

Sex differences in impulsive action and impulsive choice

PubMed Central

Weafer, Jessica; de Wit, Harriet

2013-01-01

Here, we review the evidence for sex differences in behavioral measures of impulsivity for both humans and laboratory animals. We focus on two specific components of impulsivity: impulsive action (i.e., difficulty inhibiting a prepotent response) and impulsive choice (i.e., difficulty delaying gratification). Sex differences appear to exist on these measures, but the direction and magnitude of the differences vary. In laboratory animals, impulsive action is typically greater in males than females, whereas impulsive choice is typically greater in females. In humans, women discount more steeply than men, but sex differences on measures of impulsive action depend on tasks and subject samples. We discuss implications of these findings as they relate to drug addiction. We also point out the major gaps in this research to date, including the lack of studies designed specifically to examine sex differences in behavioral impulsivity, and the lack of consideration of menstrual or estrous phase or sex hormone levels in the studies. PMID:24286704

Sex-Biased Gene Expression and Sexual Conflict throughout Development

PubMed Central

Ingleby, Fiona C.; Flis, Ilona; Morrow, Edward H.

2015-01-01

Sex-biased gene expression is likely to account for most sexually dimorphic traits because males and females share much of their genome. When fitness optima differ between sexes for a shared trait, sexual dimorphism can allow each sex to express their optimum trait phenotype, and in this way, the evolution of sex-biased gene expression is one mechanism that could help to resolve intralocus sexual conflict. Genome-wide patterns of sex-biased gene expression have been identified in a number of studies, which we review here. However, very little is known about how sex-biased gene expression relates to sex-specific fitness and about how sex-biased gene expression and conflict vary throughout development or across different genotypes, populations, and environments. We discuss the importance of these neglected areas of research and use data from a small-scale experiment on sex-specific expression of genes throughout development to highlight potentially interesting avenues for future research. PMID:25376837

Sex differences in the psychopharmacological treatment of depression.

PubMed

Sramek, John J; Murphy, Michael F; Cutler, Neal R

2016-12-01

Although a number of studies have observed that females respond better to serotonergic antidepressants than males and that postmenopausal females have a diminished response to antidepressants compared with younger females, there are also studies that conflict with both of these findings, making any generalizations regarding sex differences difficult to make. Sex variance in antidepressant efficacy and pharmacokinetics profiles have been attributed to sex-based physiological differences, behavioral differences, related disorders, and sex-specific conditions, including pregnancy and menopause. This paper will review the history and current research on sex effects of antidepressant treatment.

Detection of Allelic Frequency Differences between the Sexes in Humans: A Signature of Sexually Antagonistic Selection.

PubMed

Lucotte, Elise A; Laurent, Romain; Heyer, Evelyne; Ségurel, Laure; Toupance, Bruno

2016-06-02

Sexually antagonistic (SA) selection, a form of selection that can occur when both sexes have different fitness optima for a trait, is a major force shaping the evolution of organisms. A seminal model developed by Rice (Rice WR. 1984. Sex chromosomes and the evolution of sexual dimorphism. Evolution 38:735-742.) predicts that the X chromosome should be a hotspot for the accumulation of loci under SA selection as compared with the autosomes. Here, we propose a methodological framework designed to detect a specific signature of SA selection on viability, differences in allelic frequencies between the sexes. Applying this method on genome-wide single nucleotide polymorphism (SNP) data in human populations where no sex-specific population stratification could be detected, we show that there are overall significantly more SNPs exhibiting differences in allelic frequencies between the sexes on the X chromosome as compared with autosomes, supporting the predictions of Rice's model. This pattern is consistent across populations and is robust to correction for potential biases such as differences in linkage disequilibrium, sample size, and genotyping errors between chromosomes. Although SA selection is not the only factor resulting in allelic frequency differences between the sexes, we further show that at least part of the identified X-linked loci is caused by such a sex-specific processes. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Sex-specific differences in the synaptonemal complex in the genus Oreochromis (Cichlidae).

PubMed

Campos-Ramos, Rafael; Harvey, Simon C; Penman, David J

2009-04-01

Total synaptonemal complex (SC) lengths were estimated from Oreochromis aureus Steindachner (which has a WZ/ZZ sex determination system), O. mossambicus Peters and O. niloticus L. (both of which have XX/XY sex determination systems). The total SC length in oocytes was greater than that in spermatocytes in all three species (194 +/- 30 microm and 134 +/- 13 microm, 187 +/- 22 microm and 127 +/- 17 microm, 193 +/- 37 microm and 144 +/- 19 microm, respectively). These sex-specific differences did not appear to be influenced by the type of sex determination system (the female/male total SC length ratio was 1.45 in O. aureus, 1.47 in O. mossambicus and 1.34 in O. niloticus) and do not correlate with the lack of any overall sex-specific length differences in the current Oreochromis linkage map. Although based on data from relatively few species, there appears to be no consistent relationship between sex-specific SC lengths and linkage map lengths in fish. Neomale (hormonally masculinized genetic female) O. aureus and O. mossambicus had total SC lengths of 138 +/- 13 microm and 146 +/- 13 microm respectively, more similar to normal males than to normal females. These findings agree with data from other vertebrate species that suggest that phenotypic sex, rather than genotype, determines traits such as total SC length, chiasmata position and recombination pattern, at least for the autosomes.

Sex, stressful life events, and adult onset depression and alcohol dependence: are men and women equally vulnerable?

PubMed

Slopen, Natalie; Williams, David R; Fitzmaurice, Garrett M; Gilman, Stephen E

2011-08-01

Higher rates of major depression (MD) among females, and of alcohol dependence (AD) among males, are among the most routinely reported findings in psychiatric epidemiology. One of the most often pursued explanations for sex differences in both disorders suggests that males and females have a differential vulnerability to stressors, which is manifested in sex-specific ways (MD for females, AD for males). However, existing evidence in support of this explanation is mixed. In the present study, we investigated sex differences in the association between stressful life events and MD and AD in a large national sample of adults in the United States (n = 32,744) using a prospective design. Logistic regression was used to estimate associations between stressful life events and both MD and AD; sex-specific effects of stress on MD and AD were evaluated by testing interaction terms between sex and stressors in the prediction of both outcomes. The number of stressful life events was predictive of first onset MD and AD. This was true for both males and females, and sex-by-stress interaction terms did not support the hypothesis that sex-specific responses to stressful life events lead to sex differences in first onset of MD and AD among adults. These results indicate the resistance of sex differences in MD and AD to simple explanations, and suggest the need for more nuanced models that incorporate both physiological and social aspects of vulnerability. Copyright © 2011 Elsevier Ltd. All rights reserved.

Dosage Compensation of the Sex Chromosomes

PubMed Central

Disteche, Christine M.

2013-01-01

Differentiated sex chromosomes evolved because of suppressed recombination once sex became genetically controlled. In XX/XY and ZZ/ZW systems, the heterogametic sex became partially aneuploid after degeneration of the Y or W. Often, aneuploidy causes abnormal levels of gene expression throughout the entire genome. Dosage compensation mechanisms evolved to restore balanced expression of the genome. These mechanisms include upregulation of the heterogametic chromosome as well as repression in the homogametic sex. Remarkably, strategies for dosage compensation differ between species. In organisms where more is known about molecular mechanisms of dosage compensation, specific protein complexes containing noncoding RNAs are targeted to the X chromosome. In addition, the dosage-regulated chromosome often occupies a specific nuclear compartment. Some genes escape dosage compensation, potentially resulting in sex-specific differences in gene expression. This review focuses on dosage compensation in mammals, with comparisons to fruit flies, nematodes, and birds. PMID:22974302

Sex-specific responses to climate change in plants alter population sex ratio and performance.

PubMed

Petry, William K; Soule, Judith D; Iler, Amy M; Chicas-Mosier, Ana; Inouye, David W; Miller, Tom E X; Mooney, Kailen A

2016-07-01

Males and females are ecologically distinct in many species, but whether responses to climate change are sex-specific is unknown. We document sex-specific responses to climate change in the plant Valeriana edulis (valerian) over four decades and across its 1800-meter elevation range. Increased elevation was associated with increased water availability and female frequency, likely owing to sex-specific water use efficiency and survival. Recent aridification caused male frequency to move upslope at 175 meters per decade, a rate of trait shift outpacing reported species' range shifts by an order of magnitude. This increase in male frequency reduced pollen limitation and increased seedset. Coupled with previous studies reporting sex-specific arthropod communities, these results underscore the importance of ecological differences between the sexes in mediating biological responses to climate change. Copyright © 2016, American Association for the Advancement of Science.

Genome-wide oxidative bisulfite sequencing identifies sex-specific methylation differences in the human placenta

PubMed Central

Johnson, Michelle D; Dopierala, Justyna

2018-01-01

ABSTRACT DNA methylation is an important regulator of gene function. Fetal sex is associated with the risk of several specific pregnancy complications related to placental function. However, the association between fetal sex and placental DNA methylation remains poorly understood. We carried out whole-genome oxidative bisulfite sequencing in the placentas of two healthy female and two healthy male pregnancies generating an average genome depth of coverage of 25x. Most highly ranked differentially methylated regions (DMRs) were located on the X chromosome but we identified a 225 kb sex-specific DMR in the body of the CUB and Sushi Multiple Domains 1 (CSMD1) gene on chromosome 8. The sex-specific differential methylation pattern observed in this region was validated in additional placentas using in-solution target capture. In a new RNA-seq data set from 64 female and 67 male placentas, CSMD1 mRNA was 1.8-fold higher in male than in female placentas (P value = 8.5 × 10−7, Mann-Whitney test). Exon-level quantification of CSMD1 mRNA from these 131 placentas suggested a likely placenta-specific CSMD1 isoform not detected in the 21 somatic tissues analyzed. We show that the gene body of an autosomal gene, CSMD1, is differentially methylated in a sex- and placental-specific manner, displaying sex-specific differences in placental transcript abundance. PMID:29376485

Cerebrovascular Hemodynamics in Women.

PubMed

Duque, Cristina; Feske, Steven K; Sorond, Farzaneh A

2017-12-01

Sex and gender, as biological and social factors, significantly influence health outcomes. Among the biological factors, sex differences in vascular physiology may be one specific mechanism contributing to the observed differences in clinical presentation, response to treatment, and clinical outcomes in several vascular disorders. This review focuses on the cerebrovascular bed and summarizes the existing literature on sex differences in cerebrovascular hemodynamics to highlight the knowledge deficit that exists in this domain. The available evidence is used to generate mechanistically plausible and testable hypotheses to underscore the unmet need in understanding sex-specific mechanisms as targets for more effective therapeutic and preventive strategies. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Sex differences in risk factors for cardiovascular disease: the PERU MIGRANT study.

PubMed

Bernabe-Ortiz, Antonio; Benziger, Catherine Pastorius; Gilman, Robert H; Smeeth, Liam; Miranda, J Jaime

2012-01-01

Although men and women have similar risk factors for cardiovascular disease, many social behaviors in developing countries differ by sex. Rural-to-urban migrants have different cardiovascular risk profiles than rural or urban dwellers. The objective of this study was to evaluate the sex differences with specific cardiovascular risk factors in rural-to-urban migrants. We used the rural-to-urban migrant group of the PERU MIGRANT cross-sectional study to investigate the sex differences in specific cardiovascular risk factors: obesity, hypertension, metabolic syndrome, as well as exposures of socioeconomic status, acculturation surrogates and behavioral characteristics. Logistic regression analysis was used to characterize strength of association between sex and our outcomes adjusting for potential confounders. The sample of migrants was 589 (mean age 46.5 years) and 52.4% were female. In the adjusted models, women were more likely to be obese (OR=5.97; 95%CI: 3.21-11) and have metabolic syndrome (OR=2.22; 95%CI: 1.39-3.55) than men, explaining the greatest variability for obesity and metabolic syndrome but not for hypertension. Our results suggest that interventions for CVD in Peru should be sex-specific and address the unique health needs of migrant populations living in urban shantytowns since the risk factors for obesity and metabolic syndrome differ between males and females.

Sex Differences in Trajectories of Offending among Puerto Rican Youth

ERIC Educational Resources Information Center

Jennings, Wesley G.; Maldonado-Molina, Mildred M.; Piquero, Alex R.; Odgers, Candice L.; Bird, Hector; Canino, Glorisa

2010-01-01

Although sex is one of the strongest correlates of crime, contentions remain regarding the necessity of sex-specific theories of crime. The current study examines delinquent trajectories across sex among Puerto Rican youth socialized in two different cultural contexts (Bronx, United States; and San Juan, Puerto Rico). Results indicate similar…

Neural sex modifies the function of a C. elegans sensory circuit.

PubMed

Lee, Kyunghwa; Portman, Douglas S

2007-11-06

Though sex differences in animal behavior are ubiquitous, their neural and genetic underpinnings remain poorly understood. In particular, the role of functional differences in the neural circuitry that is shared by both sexes has not been extensively investigated. We have addressed these issues with C. elegans olfaction, a simple innate behavior mediated by sexually isomorphic neurons. Though males respond to the same olfactory attractants as do hermaphrodites, we find that each sex has a characteristic repertoire of olfactory preferences. These are not secondary to other sex-specific behaviors and do not require signaling from the gonad. Sex-specific olfactory preferences are controlled by tra-1, the master regulator of C. elegans sexual differentiation. Moreover, the genetic masculinization of neurons in an otherwise wild-type hermaphrodite is sufficient to switch the sexual phenotype of olfactory preference behavior. These studies reveal novel and unexpected sex differences in a C. elegans sensory behavior that is exhibited by both sexes. Our results indicate that these differences are a function of the chromosomally determined sexual identity of shared neural circuitry.

Quantitative genetics and sex-specific selection on sexually dimorphic traits in bighorn sheep

PubMed Central

Poissant, Jocelyn; Wilson, Alastair J; Festa-Bianchet, Marco; Hogg, John T; Coltman, David W

2008-01-01

Sexual conflict at loci influencing traits shared between the sexes occurs when sex-specific selection pressures are antagonistic relative to the genetic correlation between the sexes. To assess whether there is sexual conflict over shared traits, we estimated heritability and intersexual genetic correlations for highly sexually dimorphic traits (horn volume and body mass) in a wild population of bighorn sheep (Ovis canadensis) and quantified sex-specific selection using estimates of longevity and lifetime reproductive success. Body mass and horn volume showed significant additive genetic variance in both sexes, and intersexual genetic correlations were 0.24±0.28 for horn volume and 0.63±0.30 for body mass. For horn volume, selection coefficients did not significantly differ from zero in either sex. For body weight, selection coefficients were positive in females but did not differ from zero in males. The absence of detectable sexually antagonistic selection suggests that currently there are no sexual conflicts at loci influencing horn volume and body mass. PMID:18211870

Sex and gender differences in therapy of type 2 diabetes.

PubMed

Kautzky-Willer, Alexandra; Harreiter, Jürgen

2017-09-01

Clinical guidelines for the management of type 2 diabetes recommend individual therapy considering age, duration of disease, presence of complication and risk of hypoglycaemia. However, at present, the patient's sex has no impact on clinical decisions. Yet, there is mounting data pointing at biological and psychosocial differences between men and women with great impact on progression of disease and complications. Moreover, choices and preferences of therapeutic strategies as well as adherence to lifestyle and pharmacological interventions differ in both sexes. In addition, drug therapy may have sex-specific side effects. Therefore, there is need of more research on biological differences and of evidence-based individualised targeted sex-sensitive therapeutic concepts. Clinical guidelines must consider relevant sex-differences. Development and implementation of sex-specific programs may help to improve adherence to therapy and to reduce progression of disease and development of complications. A more gender-sensitive clinical approach may improve quality of life and increase health and life expectancy in men and women with type 2 diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification of sex-specific urinary biomarkers for major depressive disorder by combined application of NMR- and GC-MS-based metabonomics.

PubMed

Zheng, P; Chen, J-J; Zhou, C-J; Zeng, L; Li, K-W; Sun, L; Liu, M-L; Zhu, D; Liang, Z-H; Xie, P

2016-11-15

Women are more vulnerable to major depressive disorder (MDD) than men. However, molecular biomarkers of sex differences are limited. Here we combined gas chromatography-mass spectrometry (GC-MS)- and nuclear magnetic resonance (NMR)-based metabonomics to investigate sex differences of urinary metabolite markers in MDD, and further explore their potential of diagnosing MDD. Consequently, the metabolite signatures of women and men MDD subjects were significantly different from of that in their respective healthy controls (HCs). Twenty seven women and 36 men related differentially expressed metabolites were identified in MDD. Fourteen metabolites were changed in both women and men MDD subjects. Significantly, the women-specific (m-Hydroxyphenylacetate, malonate, glycolate, hypoxanthine, isobutyrate and azelaic acid) and men-specific (tyrosine, N-acetyl-d-glucosamine, N-methylnicotinamide, indoxyl sulfate, citrate and succinate) marker panels were further identified, which could differentiate men and women MDD patients from their respective HCs with higher accuracy than previously reported sex-nonspecific marker panels. Our findings demonstrate that men and women MDD patients have distinct metabonomic signatures and sex-specific biomarkers have promising values in diagnosing MDD.

Does the silver moss Bryum argenteum exhibit sex-specific patterns in vegetative growth rate, asexual fitness or prezygotic reproductive investment?

PubMed

Horsley, Kimberly; Stark, Lloyd R; McLetchie, D Nicholas

2011-05-01

Expected life history trade-offs associated with sex differences in reproductive investment are often undetected in seed plants, with the difficulty arising from logistical issues of conducting controlled experiments. By controlling genotype, age and resource status of individuals, a bryophyte was assessed for sex-specific and location-specific patterns of vegetative, asexual and sexual growth/reproduction across a regional scale. Twelve genotypes (six male, six female) of the dioecious bryophyte Bryum argenteum were subcultured to remove environmental effects, regenerated asexually to replicate each genotype 16 times, and grown over a period of 92 d. Plants were assessed for growth rates, asexual and sexual reproductive traits, and allocation to above- and below-ground regenerative biomass. The degree of sexual versus asexual reproductive investment appears to be under genetic control, with three distinct ecotypes found in this study. Protonemal growth rate was positively correlated with asexual reproduction and sexual reproduction, whereas asexual reproduction was negatively correlated (appeared to trade-off) with vegetative growth (shoot production). No sex-specific trade-offs were detected. Female sex-expressing shoots were longer than males, but the sexes did not differ in growth traits, asexual traits, sexual induction times, or above- and below-ground biomass. Males, however, had much higher rates of inflorescence production than females, which translated into a significantly higher (24x) prezygotic investment for males relative to females. Evidence for three distinct ecotypes is presented for a bryophyte based on regeneration traits. Prior to zygote production, the sexes of this bryophyte did not differ in vegetative growth traits but significantly differed in reproductive investment, with the latter differences potentially implicated in the strongly biased female sex ratio. The disparity between males and females for prezygotic reproductive investment is the highest known for bryophytes.

Analysis of sex and gender-specific research reveals a common increase in publications and marked differences between disciplines

PubMed Central

2010-01-01

Background The incorporation of sex and gender-specific analysis in medical research is increasing due to pressure from public agencies, funding bodies, and the clinical and research community. However, generations of knowledge and publication trends in this discipline are currently spread over distinct specialties and are difficult to analyze comparatively. Methods Using a text-mining approach, we have analysed sex and gender aspects in research within nine clinical subspecialties - Cardiology, Pulmonology, Nephrology, Endocrinology, Gastroenterology, Haematology, Oncology, Rheumatology, Neurology - using six paradigmatic diseases in each one. Articles have been classified into five pre-determined research categories - Epidemiology, Pathophysiology, Clinical research, Management and Outcomes. Additional information has been collected on the type of study (human/animal) and the number of subjects included. Of the 8,836 articles initially retrieved, 3,466 (39%) included sex and gender-specific research and have been further analysed. Results Literature incorporating sex/gender analysis increased over time and displays a stronger trend if compared to overall publication increase. All disciplines, but cardiology (22%), demonstrated an underrepresentation of research about gender differences in management, which ranges from 3 to 14%. While the use of animal models for identification of sex differences in basic research varies greatly among disciplines, studies involving human subjects are frequently conducted in large cohorts with more than 1,000 patients (24% of all human studies). Conclusions Heterogeneity characterizes sex and gender-specific research. Although large cohorts are often analysed, sex and gender differences in clinical management are insufficiently investigated leading to potential inequalities in health provision and outcomes. PMID:21067576

Sex-specific mechanisms for responding to stress.

PubMed

Bangasser, Debra A; Wicks, Brittany

2017-01-02

Posttraumatic stress disorder and major depression share stress as an etiological contributor and are more common in women than in men. Traditionally, preclinical studies investigating the neurobiological underpinnings of stress vulnerability have used only male rodents; however, recent studies that include females are finding sex-specific mechanisms for responding to stress. This Mini-Review examines recent literature using a framework developed by McCarthy and colleagues (2012; J Neurosci 32:2241-2247) that highlights different types of sex differences. First, we detail how learned fear responses in rats are sexually dimorphic. Then, we contrast this finding with fear extinction, which is similar in males and females at the behavioral level but at the circuitry level is associated with sex-specific cellular changes and, thus, exemplifies a sex convergence. Next, sex differences in stress hormones are detailed. Finally, the effects of stress on learning, attention, and arousal are used to highlight the concept of a sex divergence in which the behavior of males and females is similar at baseline but diverges following stressor exposure. We argue that appreciating and investigating the diversity of sex differences in stress response systems will improve our understanding of vulnerability and resilience to stress-related psychiatric disorders and likely lead to the development of novel therapeutics for better treatment of these disorders in both men and women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The end of gonad-centric sex determination in mammals

PubMed Central

Arnold, Arthur P.

2011-01-01

The 20th century theory of mammalian sex determination states that the embryo is sexually indifferent until the differentiation of gonads, after which sex differences in phenotype are caused by differential effects of gonadal hormones. That theory is inadequate because some sex differences precede differentiation of the gonads and/or are determined by non-gonadal effects of the sexual inequality in number and type of sex chromosomes. A general theory of sex determination is proposed, which recognizes multiple parallel primary sex-determining pathways initiated by genes or factors encoded by the sex chromosomes. The separate sex-specific pathways interact to synergize with or antagonize each other, enhancing or reducing sex differences in phenotype. PMID:22078126

Sex Differences in Parenting Behaviors in Single-Mother and Single-Father Households

ERIC Educational Resources Information Center

Dufur, Mikaela J.; Howell, Nyssa C.; Downey, Douglas B.; Ainsworth, James W.; Lapray, Alice J.

2010-01-01

Research on family structure has led some to claim that sex-based parenting differences exist. But if such differences exist in single-parent families, the absence of a second parent rather than specific sex-typed parenting might explain them. We examine differences in mothering and fathering behavior in single-parent households, where number of…

Sex-specific microRNA expression networks in an acute mouse model of ozone-induced lung inflammation.

PubMed

Fuentes, Nathalie; Roy, Arpan; Mishra, Vikas; Cabello, Noe; Silveyra, Patricia

2018-05-08

Sex differences in the incidence and prognosis of respiratory diseases have been reported. Studies have shown that women are at increased risk of adverse health outcomes from air pollution than men, but sex-specific immune gene expression patterns and regulatory networks have not been well studied in the lung. MicroRNAs (miRNAs) are environmentally sensitive posttranscriptional regulators of gene expression that may mediate the damaging effects of inhaled pollutants in the lung, by altering the expression of innate immunity molecules. Male and female mice of the C57BL/6 background were exposed to 2 ppm of ozone or filtered air (control) for 3 h. Female mice were also exposed at different stages of the estrous cycle. Following exposure, lungs were harvested and total RNA was extracted. We used PCR arrays to study sex differences in the expression of 84 miRNAs predicted to target inflammatory and immune genes. We identified differentially expressed miRNA signatures in the lungs of male vs. female exposed to ozone. In silico pathway analyses identified sex-specific biological networks affected by exposure to ozone that ranged from direct predicted gene targeting to complex interactions with multiple intermediates. We also identified differences in miRNA expression and predicted regulatory networks in females exposed to ozone at different estrous cycle stages. Our results indicate that both sex and hormonal status can influence lung miRNA expression in response to ozone exposure, indicating that sex-specific miRNA regulation of inflammatory gene expression could mediate differential pollution-induced health outcomes in men and women.

A Transcriptome Derived Female-Specific Marker from the Invasive Western Mosquitofish (Gambusia affinis)

PubMed Central

Lamatsch, Dunja K.; Adolfsson, Sofia; Senior, Alistair M.; Christiansen, Guntram; Pichler, Maria; Ozaki, Yuichi; Smeds, Linnea; Schartl, Manfred; Nakagawa, Shinichi

2015-01-01

Sex-specific markers are a prerequisite for understanding reproductive biology, genetic factors involved in sex differences, mechanisms of sex determination, and ultimately the evolution of sex chromosomes. The Western mosquitofish, Gambusia affinis, may be considered a model species for sex-chromosome evolution, as it displays female heterogamety (ZW/ZZ), and is also ecologically interesting as a worldwide invasive species. Here, de novo RNA-sequencing on the gonads of sexually mature G. affinis was used to identify contigs that were highly transcribed in females but not in males (i.e., transcripts with ovary-specific expression). Subsequently, 129 primer pairs spanning 79 contigs were tested by PCR to identify sex-specific transcripts. Of those primer pairs, one female-specific DNA marker was identified, Sanger sequenced and subsequently validated in 115 fish. Sequence analyses revealed a high similarity between the identified sex-specific marker and the 3´ UTR of the aminomethyl transferase (amt) gene of the closely related platyfish (Xiphophorus maculatus). This is the first time that RNA-seq has been used to successfully characterize a sex-specific marker in a fish species in the absence of a genome map. Additionally, the identified sex-specific marker represents one of only a handful of such markers in fishes. PMID:25707007

Cross-sex genetic correlation does not extend to sexual size dimorphism in spiders

NASA Astrophysics Data System (ADS)

Turk, Eva; Kuntner, Matjaž; Kralj-Fišer, Simona

2018-02-01

Males and females are often subjected to different selection pressures for homologous traits, resulting in sex-specific optima. Because organismal attributes usually share their genetic architectures, sex-specific selection may lead to intralocus sexual conflict. Evolution of sexual dimorphism may resolve this conflict, depending on the degree of cross-sex genetic correlation ( r MF) and the strength of sex-specific selection. In theory, high r MF implies that sexes largely share the genetic base for a given trait and are consequently sexually monomorphic, while low r MF indicates a sex-specific genetic base and sexual dimorphism. Here, we broadly test this hypothesis on three spider species with varying degrees of female-biased sexual size dimorphism, Larinioides sclopetarius (sexual dimorphism index, SDI = 0.85), Nuctenea umbratica (SDI = 0.60), and Zygiella x-notata (SDI = 0.46). We assess r MF via same-sex and opposite-sex heritability estimates. We find moderate body mass heritability but no obvious patterns in sex-specific heritability. Against the prediction, the degree of sexual size dimorphism is unrelated to the relative strength of same-sex versus opposite-sex heritability. Our results do not support the hypothesis that sexual size dimorphism is negatively associated with r MF. We conclude that sex-specific genetic architecture may not be necessary for the evolution of a sexually dimorphic trait.

Sex-dependent genetic effects on immune responses to a parasitic nematode.

PubMed

Hayes, Kelly S; Hager, Reinmar; Grencis, Richard K

2014-03-14

Many disease aetiologies have sex specific effects, which have important implications for disease management. It is now becoming increasingly evident that such effects are the result of the differential expression of autosomal genes rather than sex-specific genes. Such sex-specific variation in the response to Trichuris muris, a murine parasitic nematode infection and model for the human parasitic nematode T. trichiura, has been well documented, however, the underlying genetic causes of these differences have been largely neglected. We used the BXD mouse set of recombinant inbred strains to identify sex-specific loci that contribute to immune phenotypes in T. muris infection. Response phenotypes to T. muris infection were found to be highly variable between different lines of BXD mice. A significant QTL on chromosome 5 (TM5) associated with IFN-γ production was found in male mice but not in female mice. This QTL was in the same location as a suggestive QTL for TNF-α and IL-6 production in male mice suggesting a common control of these pro-inflammatory cytokines. A second QTL was identified on chromosome 4 (TM4) affecting worm burden in both male and female cohorts. We have identified several genes as potential candidates for modifying responses to T. muris infection. We have used the largest mammalian genetic model system, the BXD mouse population, to identify candidate genes with sex-specific effects in immune responses to T. muris infection. Some of these genes may be differentially expressed in male and female mice leading to the difference in immune response between the sexes reported in previous studies. Our study further highlights the importance of considering sex as an important factor in investigations of immune response at the genome-wide level, in particular the bias that can be introduced when generalizing results obtained from only one sex or a mixed sex population. Rather, analyses of interaction effects between sex and genotype should be part of future studies.

Sex differences in the neural substrates of spatial working memory during adolescence are not mediated by endogenous testosterone

PubMed Central

Alarcón, Gabriela; Cservenka, Anita; Fair, Damien A.; Nagel, Bonnie J.

2014-01-01

Adolescence is a developmental period characterized by notable changes in behavior, physical attributes, and an increase in endogenous sex steroid hormones, which may impact cognitive functioning. Moreover, sex differences in brain structure are present, leading to differences in neural function and cognition. Here, we examine sex differences in performance and blood oxygen level-dependent (BOLD) activation in a sample of adolescents during a spatial working memory (SWM) task. We also examine whether endogenous testosterone levels mediate differential brain activity between the sexes. Adolescents between ages 10 and 16 completed a SWM functional magnetic resonance imaging (fMRI) task, and serum hormone levels were assessed within seven days of scanning. While there were no sex differences in task performance (accuracy and reaction time), differences in BOLD response between girls and boys emerged, with girls deactivating brain regions in the default mode network and boys showing increased response in SWM-related brain regions of the frontal cortex. These results suggest that adolescent boys and girls adopted distinct neural strategies, while maintaining spatial cognitive strategies that facilitated comparable cognitive performance of a SWM task. A nonparametric bootstrapping procedure revealed that testosterone did not mediate sex-specific brain activity, suggesting that sex differences in BOLD activation during SWM may be better explained by other factors, such as early organizational effects of sex steroids or environmental influences. Elucidating sex differences in neural function and the influence of gonadal hormones can serve as a basis of comparison for understanding sexually dimorphic neurodevelopment and inform sex-specific psychopathology that emerges in adolescence. PMID:25312831

Intermittent whole-body cold immersion induces similar thermal stress but different motor and cognitive responses between males and females.

PubMed

Solianik, Rima; Skurvydas, Albertas; Mickevičienė, Dalia; Brazaitis, Marius

2014-10-01

The main aim of this study was to compare the thermal responses and the responses of cognitive and motor functions to intermittent cold stress between males and females. The intermittent cold stress continued until rectal temperature (TRE) reached 35.5°C or for a maximum of 170 min. Thermal response and motor and cognitive performance were monitored. During intermittent cold stress, body temperature variables decreased in all subjects (P < 0.001) and did not differ between sexes. The presence of fast and slow cooling types for participants with similar effect on physiological variables were observed; thus the different rate coolers were grouped together and were attributed only sex specific responses. Overall, TRE cooling rate and cold strain index did not differ between sexes. Maximal voluntary contraction (MVC) decreased after intermittent cold exposure only in males (P < 0.001), whereas changes in muscle electromyography (EMG) activity did not differ between sexes. The effects of intermittent cold stress on electrically evoked muscle properties, spinal (H-reflex), and supraspinal (V-waves) reflexes did not differ between sexes. Intermittent cold-induced cognitive perturbation of attention and memory task performance was greater in males (P < 0.05). Contrary to our expectations, the results of the present study indicated that males and females experience similar thermal stress induced by intermittent whole-body cold immersion. Although no sex-specific differences were observed in muscle EMG activity, involuntary muscle properties, spinal and supraspinal reflexes, some of the sex differences observed (e.g., lower isometric MVC and greater cognitive perturbation in males) support the view of sex-specific physiological responses to core temperature decrease. Copyright © 2014 Elsevier Inc. All rights reserved.

Testosterone-mediated sex differences in the face shape during adolescence: subjective impressions and objective features.

PubMed

Marečková, Klára; Weinbrand, Zohar; Chakravarty, M Mallar; Lawrence, Claire; Aleong, Rosanne; Leonard, Gabriel; Perron, Michel; Pike, G Bruce; Richer, Louis; Veillette, Suzanne; Pausova, Zdenka; Paus, Tomáš

2011-11-01

Sex identification of a face is essential for social cognition. Still, perceptual cues indicating the sex of a face, and mechanisms underlying their development, remain poorly understood. Previously, our group described objective age- and sex-related differences in faces of healthy male and female adolescents (12-18 years of age), as derived from magnetic resonance images (MRIs) of the adolescents' heads. In this study, we presented these adolescent faces to 60 female raters to determine which facial features most reliably predicted subjective sex identification. Identification accuracy correlated highly with specific MRI-derived facial features (e.g. broader forehead, chin, jaw, and nose). Facial features that most reliably cued male identity were associated with plasma levels of testosterone (above and beyond age). Perceptible sex differences in face shape are thus associated with specific facial features whose emergence may be, in part, driven by testosterone. Copyright © 2011 Elsevier Inc. All rights reserved.

Sex differences in antiplatelet response in ischemic stroke.

PubMed

Meyer, Dawn M; Eastwood, Jo-Ann; Compton, Margaret P; Gylys, Karen; Zivin, Justin A; Ovbiagele, Bruce

2011-07-01

Sex differences exist in the occurrence, treatment and outcome of ischemic stroke. Compared with men, women have more stroke events and are less likely to fully recover from a stroke. Given the rapidly aging population, stroke incidence and mortality among women are projected to substantially rise by 2050. This has important public health consequences. Mitigating the burden of stroke among women will require a fundamental understanding of sex differences and sex-specific issues including cerebrovascular disease pathophysiology, treatment and outcome. An aspect of stroke treatment receiving increasing but insufficient attention involves possible interactions between estrogen levels, antiplatelet drugs and stroke outcome. Emerging evidence suggests that antiplatelet therapy may provide primary stroke protection but not primary myocardial infarction prevention in women, while the opposite may be true among men. Understanding sex-specific issues related to women who experience stroke is critical to clinicians who treat women with antiplatelet medications as part of a secondary stroke prevention regimen; however, the ideal antiplatelet medication, and dose, in women requires further research. In this article we present a conceptual framework for sex differences in antiplatelet treatment response in ischemic stroke, thrombus formation and the mediating role of estrogen, sex differences in antiplatelet treatment response in clinical trials, and sex differences in antiplatelet treatment use in ischemic stroke.

Sex differences in antiplatelet response in ischemic stroke

PubMed Central

Meyer, Dawn M; Eastwood, Jo-Ann; Compton, Margaret P; Gylys, Karen; Zivin, Justin A; Ovbiagele, Bruce

2011-01-01

Sex differences exist in the occurrence, treatment and outcome of ischemic stroke. Compared with men, women have more stroke events and are less likely to fully recover from a stroke. Given the rapidly aging population, stroke incidence and mortality among women are projected to substantially rise by 2050. This has important public health consequences. Mitigating the burden of stroke among women will require a fundamental understanding of sex differences and sex-specific issues including cerebrovascular disease pathophysiology, treatment and outcome. An aspect of stroke treatment receiving increasing but insufficient attention involves possible interactions between estrogen levels, antiplatelet drugs and stroke outcome. Emerging evidence suggests that antiplatelet therapy may provide primary stroke protection but not primary myocardial infarction prevention in women, while the opposite may be true among men. Understanding sex-specific issues related to women who experience stroke is critical to clinicians who treat women with antiplatelet medications as part of a secondary stroke prevention regimen; however, the ideal antiplatelet medication, and dose, in women requires further research. In this article we present a conceptual framework for sex differences in antiplatelet treatment response in ischemic stroke, thrombus formation and the mediating role of estrogen, sex differences in antiplatelet treatment response in clinical trials, and sex differences in antiplatelet treatment use in ischemic stroke. PMID:21790339

Mechanisms of Sex Differences in Fear and Posttraumatic Stress Disorder.

PubMed

Ramikie, Teniel Sonya; Ressler, Kerry J

2018-05-15

Following sexual maturity, females disproportionately have higher rates of posttraumatic stress disorder (PTSD) and experience greater symptom severity and chronicity as compared with males. This observation has led many to examine sex differences in PTSD risk factors. Though relatively few, these studies reveal that the root causes of PTSD sex differences are complex, and partly represent interactions between sex-specific nonbiological and biological risk factors, which differentially shape PTSD vulnerability. Moreover, these studies suggest that sex-specific PTSD vulnerability is partly regulated by sex differences in fear systems. Fear, which represents a highly conserved adaptive response to threatening environmental stimuli, becomes pathological in trauma- and stress-based psychiatric syndromes, such as PTSD. Over the last 30 years, considerable progress has been made in understanding normal and pathological molecular and behavioral fear processes in humans and animal models. Thus, fear mechanisms represent a tractable PTSD biomarker in the study of sex differences in fear. In this review, we discuss studies that examine nonbiological and biological sex differences that contribute to normal and pathological fear behaviors in humans and animal models. This, we hope, will shed greater light on the potential mechanisms that contribute to increased PTSD vulnerability in females. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Sex differences in oxidative stress resistance in relation to longevity in Drosophila melanogaster.

PubMed

Niveditha, S; Deepashree, S; Ramesh, S R; Shivanandappa, T

2017-10-01

Gender differences in lifespan and aging are known across species. Sex differences in longevity within a species can be useful to understand sex-specific aging. Drosophila melanogaster is a good model to study the problem of sex differences in longevity since females are longer lived than males. There is evidence that stress resistance influences longevity. The objective of this study was to investigate if there is a relationship between sex differences in longevity and oxidative stress resistance in D. melanogaster. We observed a progressive age-dependent decrease in the activity of SOD and catalase, major antioxidant enzymes involved in defense mechanisms against oxidative stress in parallel to the increased ROS levels over time. Longer-lived females showed lower ROS levels and higher antioxidant enzymes than males as a function of age. Using ethanol as a stressor, we have shown differential susceptibility of the sexes to ethanol wherein females exhibited higher resistance to ethanol-induced mortality and locomotor behavior compared to males. Our results show strong correlation between sex differences in oxidative stress resistance, antioxidant defenses and longevity. The study suggests that higher antioxidant defenses in females may confer resistance to oxidative stress, which could be a factor that influences sex-specific aging in D. melanogaster.

Reproduction reduces photosynthetic capacity in females of the subdioecious Honckenya peploides

NASA Astrophysics Data System (ADS)

Sánchez-Vilas, Julia; Retuerto, Rubén

2011-03-01

As a consequence of the different reproductive functions performed by the sexes, sexually dimorphic/polymorphic plants may exhibit gender-related variations in the energy and resources allocated to reproduction, and in the physiological processes that underlie these differences. This study investigated whether the sexes of the subdioecious plant Honckenya peploides differ in ecophysiological traits related to photosynthetic capacity and whether possible differences depend on reproductive status and on the plant's position (edge or centre) in the population. We registered in three sites in NW Spain, the sex and density of shoots of two segregated clumps of plants. These clumps represent an extreme case of sex-ratio variation across space, with separated single-sex clumps of plants. In two of these sites we measured photosynthetic efficiencies, chlorophyll content, and specific leaf areas. In females, reproduction reduced photochemical efficiency, chlorophyll content and increased the specific leaf area, which is a key leaf trait related to photosynthetic capacity. In males, no differences due to reproduction were detected. The position within the clump affected the specific leaf area of the shoots, with shoots growing at the edge having the lowest values, regardless of the sex. Finally, the effects of position in photosynthetic efficiency and chlorophyll content where highly variable among clumps. We conclude that the differential effects of reproduction on sexes may entail different costs that could be crucial in the outcome of interactions between them, contributing to their spatial segregation.

Maternal provision of non-sex-specific transformer messenger RNA in sex determination of the wasp Asobara tabida.

PubMed

Geuverink, E; Verhulst, E C; van Leussen, M; van de Zande, L; Beukeboom, L W

2018-02-01

In many insect species maternal provision of sex-specifically spliced messenger RNA (mRNA) of sex determination genes is an essential component of the sex determination mechanism. In haplodiploid Hymenoptera, maternal provision in combination with genomic imprinting has been shown for the parasitoid Nasonia vitripennis, known as maternal effect genomic imprinting sex determination (MEGISD). Here, we characterize the sex determination cascade of Asobara tabida, another hymenopteran parasitoid. We show the presence of the conserved sex determination genes doublesex (dsx), transformer (tra) and transformer-2 (tra2) orthologues in As. tabida. Of these, At-dsx and At-tra are sex-specifically spliced, indicating a conserved function in sex determination. At-tra and At-tra2 mRNA is maternally provided to embryos but, in contrast to most studied insects, As. tabida females transmit a non-sex-specific splice form of At-tra mRNA to the eggs. In this respect, As. tabida sex determination differs from the MEGISD mechanism. How the paternal genome can induce female development in the absence of maternal provision of sex-specifically spliced mRNA remains an open question. Our study reports a hitherto unknown variant of maternal effect sex determination and accentuates the diversity of insect sex determination mechanisms. © 2017 The Authors. Insect Molecular Biology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.

The influence of sex steroids on structural brain maturation in adolescence.

PubMed

Koolschijn, P Cédric M P; Peper, Jiska S; Crone, Eveline A

2014-01-01

Puberty reflects a period of hormonal changes, physical maturation and structural brain reorganization. However, little attention has been paid to what extent sex steroids and pituitary hormones are associated with the refinement of brain maturation across adolescent development. Here we used high-resolution structural MRI scans from 215 typically developing individuals between ages 8-25, to examine the association between cortical thickness, surface area and (sub)cortical brain volumes with luteinizing hormone, testosterone and estradiol, and pubertal stage based on self-reports. Our results indicate sex-specific differences in testosterone related influences on gray matter volumes of the anterior cingulate cortex after controlling for age effects. No significant associations between subcortical structures and sex hormones were found. Pubertal stage was not a stronger predictor than chronological age for brain anatomical differences. Our findings indicate that sex steroids are associated with cerebral gray matter morphology in a sex specific manner. These hormonal and morphological differences may explain in part differences in brain development between boys and girls.

Contribution of knee flexor and extensor strength on sex-specific energy absorption and torsional joint stiffness during drop jumping.

PubMed

Schmitz, Randy J; Shultz, Sandra J

2010-01-01

Lower extremity injury often occurs during abrupt deceleration when attempting to change the body's direction. Although sex-specific biomechanics have been implicated in the greater risk of acute knee injury in women than in men, it is unknown if sex differences in thigh strength affect sex-specific energy absorption and torsional joint stiffness patterns. To determine sex differences in energy absorption patterns and joint stiffnesses of the lower extremity during a drop jump and to determine if these sex differences were predicted by knee extensor and flexor strength. Cross-sectional study. Laboratory environment. Recreationally active, college-aged students (41 women: age  =  22.1 ± 2.9 years, height  =  1.63 ± 0.07 m, mass  =  59.3 ± 8.0 kg; 40 men: age  =  22.4 ± 2.8 years, height  =  1.77 ± 0.1 m, mass  =  80.9 ± 14.1 kg). Participants performed knee flexor and extensor maximal voluntary isometric contractions followed by double-leg drop-jump landings. Lower extremity joint energetics (J × N(-1) × m(-1)) and torsional joint stiffnesses (Nm × N(-1) × m(-1) × degrees(-1)) were calculated for the hip, knee, and ankle during the initial landing phase. Body weight was measured in newtons and height was measured in meters. Sex comparisons were made and sex-specific regressions determined if thigh muscle strength (Nm/kg) predicted sagittal-plane landing energetics and stiffnesses. Women absorbed 69% more knee energy and had 36% less hip torsional stiffness than men. In women, greater knee extensor strength predicted greater knee energy absorption (R(2)  =  0.11, P  =  .04), and greater knee flexor strength predicted greater hip torsional stiffness (R(2)  =  0.12, P  =  .03). Sex-specific biomechanics during the deceleration phase of a drop jump revealed that women used a strategy to attempt to decrease system stiffness. Additionally, only female strength values were predictive of landing energetics and stiffnesses. These findings collectively demonstrated that the task may have been more difficult for women, resulting in a different movement strategy among those with different levels of thigh strength to safely complete the task. Future researchers should look at other predictive factors of observed sex differences.

Molecular cloning and functional characterization of the sex-determination gene doublesex in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Coleoptera, Tenebrionidae)

PubMed Central

Gotoh, Hiroki; Ishiguro, Mai; Nishikawa, Hideto; Morita, Shinichi; Okada, Kensuke; Miyatake, Takahisa; Yaginuma, Toshinobu; Niimi, Teruyuki

2016-01-01

Various types of weapon traits found in insect order Coleoptera are known as outstanding examples of sexually selected exaggerated characters. It is known that the sex determination gene doublesex (dsx) plays a significant role in sex-specific expression of weapon traits in various beetles belonging to the superfamily Scarabaeoidea. Although sex-specific weapon traits have evolved independently in various Coleopteran groups, developmental mechanisms of sex-specific expression have not been studied outside of the Scarabaeoidea. In order to test the hypothesis that dsx-dependent sex-specific expression of weapon traits is a general mechanism among the Coleoptera, we have characterized the dsx in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Tenebrionidea, Tenebirionidae). By using molecular cloning, we identified five splicing variants of Gnatocerus cornutus dsx (Gcdsx), which are predicted to code four different isoforms. We found one male-specific variant (GcDsx-M), two female-specific variants (GcDsx-FL and GcDsx-FS) and two non-sex-specific variants (correspond to a single isoform, GcDsx-C). Knockdown of all Dsx isoforms resulted in intersex phenotype both in male and female. Also, knockdown of all female-specific isoforms transformed females to intersex phenotype, while did not affect male phenotype. Our results clearly illustrate the important function of Gcdsx in determining sex-specific trait expression in both sexes. PMID:27404087

Maternal Diets Trigger Sex-Specific Divergent Trajectories of Gene Expression and Epigenetic Systems in Mouse Placenta

PubMed Central

Gabory, Anne; Ferry, Laure; Fajardy, Isabelle; Jouneau, Luc; Gothié, Jean-David; Vigé, Alexandre; Fleur, Cécile; Mayeur, Sylvain; Gallou-Kabani, Catherine; Gross, Marie-Sylvie; Attig, Linda; Vambergue, Anne; Lesage, Jean; Reusens, Brigitte; Vieau, Didier; Remacle, Claude; Jais, Jean-Philippe; Junien, Claudine

2012-01-01

Males and females responses to gestational overnutrition set the stage for subsequent sex-specific differences in adult onset non communicable diseases. Placenta, as a widely recognized programming agent, contibutes to the underlying processes. According to our previous findings, a high-fat diet during gestation triggers sex-specific epigenetic alterations within CpG and throughout the genome, together with the deregulation of clusters of imprinted genes. We further investigated the impact of diet and sex on placental histology, transcriptomic and epigenetic signatures in mice. Both basal gene expression and response to maternal high-fat diet were sexually dimorphic in whole placentas. Numerous genes showed sexually dimorphic expression, but only 11 genes regardless of the diet. In line with the key role of genes belonging to the sex chromosomes, 3 of these genes were Y-specific and 3 were X-specific. Amongst all the genes that were differentially expressed under a high-fat diet, only 16 genes were consistently affected in both males and females. The differences were not only quantitative but remarkably qualitative. The biological functions and networks of genes dysregulated differed markedly between the sexes. Seven genes of the epigenetic machinery were dysregulated, due to effects of diet, sex or both, including the Y- and X-linked histone demethylase paralogues Kdm5c and Kdm5d, which could mark differently male and female epigenomes. The DNA methyltransferase cofactor Dnmt3l gene expression was affected, reminiscent of our previous observation of changes in global DNA methylation. Overall, this striking sexual dimorphism of programming trajectories impose a considerable revision of the current dietary interventions protocols. PMID:23144842

Between-sex differences in romantic jealousy: substance or spin? A qualitative analysis.

PubMed

Fussell, Nicola J; Stollery, Brian T

2012-03-29

An influential evolutionary account of romantic jealousy proposes that natural selection shaped a specific sexually-dimorphic psychological mechanism in response to relationship threat. However, this account has faced considerable theoretical and methodological criticism and it remains unclear whether putative sex differences in romantic jealousy actually exist and, if they do, whether they are consistent with its predictions. Given the multidimensional nature of romantic jealousy, the current study employed a qualitative design to examine these issues. We report the results of sixteen semi-structured interviews that were conducted with heterosexual men and women with the purpose of exploring the emotions, cognitions and behaviors that formed their subjective, lived experience in response to relationship threat. Interpretative phenomenological analysis revealed four super-ordinate themes ("threat appraisal", "emotional episodes", "sex-specific threat" and "forgive and forget") and unequivocal sex differences in romantic jealousy consistent with the evolutionary account. Self-esteem, particularly when conceptualized as an index of mate value, emerged as an important proximal mediator for both sexes. However, specific outcomes were dependent upon domains central to the individual's self concept that were primarily sex-specific. The findings are integrated within the context of existing self-esteem and evolutionary theory and future directions for romantic jealousy research are suggested.

Strategies and methods to study female-specific cardiovascular health and disease: a guide for clinical scientists.

PubMed

Ouyang, Pamela; Wenger, Nanette K; Taylor, Doris; Rich-Edwards, Janet W; Steiner, Meir; Shaw, Leslee J; Berga, Sarah L; Miller, Virginia M; Merz, Noel Bairey

2016-01-01

In 2001, the Institute of Medicine's (IOM) report, "Exploring the Biological Contributions to Human Health: Does Sex Matter?" advocated for better understanding of the differences in human diseases between the sexes, with translation of these differences into clinical practice. Sex differences are well documented in the prevalence of cardiovascular (CV) risk factors, the clinical manifestation and incidence of cardiovascular disease (CVD), and the impact of risk factors on outcomes. There are also physiologic and psychosocial factors unique to women that may affect CVD risk, such as issues related to reproduction. The Society for Women's Health Research (SWHR) CV Network compiled an inventory of sex-specific strategies and methods for the study of women and CV health and disease across the lifespan. References for methods and strategy details are provided to gather and evaluate this information. Some items comprise robust measures; others are in development. To address female-specific CV health and disease in population, physiology, and clinical trial research, data should be collected on reproductive history, psychosocial variables, and other factors that disproportionately affect CVD in women. Variables related to reproductive health include the following: age of menarche, menstrual cycle regularity, hormone levels, oral contraceptive use, pregnancy history/complications, polycystic ovary syndrome (PCOS) components, menopause age, and use and type of menopausal hormone therapy. Other factors that differentially affect women's CV risk include diabetes mellitus, autoimmune inflammatory disease, and autonomic vasomotor control. Sex differences in aging as well as psychosocial variables such as depression and stress should also be considered. Women are frequently not included/enrolled in mixed-sex CVD studies; when they are included, information on these variables is generally not collected. These omissions limit the ability to determine the role of sex-specific contributors to CV health and disease. Lack of sex-specific knowledge contributes to the CVD health disparities that women face. The purpose of this review is to encourage investigators to consider ways to increase the usefulness of physiological and psychosocial data obtained from clinical populations, in an effort to improve the understanding of sex differences in clinical CVD research and health-care delivery for women and men.

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

PubMed

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

2016-09-30

The sex drive hypothesis predicts that stronger selection on male traits has resulted in masculinization of the genome. Here we test whether such masculinizing effects can be detected at the level of the transcriptome and methylome in the adult zebrafish brain. Although methylation is globally similar, we identified 914 specific differentially methylated CpGs (DMCs) between males and females (435 were hypermethylated and 479 were hypomethylated in males compared to females). These DMCs were prevalent in gene body, intergenic regions and CpG island shores. We also discovered 15 distinct CpG clusters with striking sex-specific DNA methylation differences. In contrast, at transcriptome level, more female-biased genes than male-biased genes were expressed, giving little support for the male sex drive hypothesis. Our study provides genome-wide methylome and transcriptome assessment and sheds light on sex-specific epigenetic patterns and in zebrafish for the first time. Copyright © 2016 Elsevier B.V. All rights reserved.

Sex Differences in General Knowledge: Meta-Analysis and New Data on the Contribution of School-Related Moderators among High-School Students

PubMed Central

Tran, Ulrich S.; Hofer, Agnes A.; Voracek, Martin

2014-01-01

Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge. PMID:25347190

Sex differences in general knowledge: meta-analysis and new data on the contribution of school-related moderators among high-school students.

PubMed

Tran, Ulrich S; Hofer, Agnes A; Voracek, Martin

2014-01-01

Research from various countries consistently reported an advantage of boys over girls in general knowledge and was also suggestive of some overall trends regarding specific domains of general knowledge that were speculated to stem from biologically differentiated interests. However, results were heterogeneous and, as of yet, had not been evaluated meta-analytically. Moreover, previous research drew on overly homogeneous high-school or undergraduate samples whose representativeness appears problematic; mostly, likely moderators, such as school type, student age or parental education, were also not directly investigated or controlled for. We provide a meta-analytical aggregation of available results regarding sex differences in general knowledge and present new data, investigating the psychometric properties of the General Knowledge Test (GKT), on which previous research primarily relied, and explored sex differences in a large and heterogeneous Austrian high-school student sample (N = 1088). The aggregated sex effect in general knowledge was of medium size in previous research, but differences in specific domains were heterogeneous across countries and only modest at best. Large sex differences in our data could be explained to a large part by school-related moderators (school type, school, student age, parental education) and selection processes. Boys had a remaining advantage over girls that was only small in size and that was consistent with the magnitude of sex differences in general intelligence. Analysis of the GKT yielded no evidence of biologically differentiated interests, but of a specific interest in the humanities among girls. In conclusion, previous research likely overestimated sex differences in general knowledge.

Proximate Sources of Population Sex Imbalance in India

PubMed Central

OSTER, EMILY

2009-01-01

There is a population sex imbalance in India. Despite a consensus that this imbalance is due to excess female mortality, the specific source of this excess mortality remains poorly understood. I use microdata on child survival in India to analyze the proximate sources of the sex imbalance. I address two questions: when in life does the sex imbalance arise, and what health or nutritional investments are specifically responsible for its appearance? I present a new methodology that uses microdata on child survival. This methodology explicitly takes into account both the possibility of naturally occurring sex differences in survival and possible differences between investments in their importance for survival. Consistent with existing literature, I find significant excess female mortality in childhood, particularly between the ages of 1 and 5, and argue that the sex imbalance that exists by age 5 is large enough to explain virtually the entire imbalance in the population. Within this age group, sex differences in vaccinations explain between 20% and 30% of excess female mortality, malnutrition explains an additional 20%, and differences in treatment for illness play a smaller role. Together, these investments account for approximately 50% of the sex imbalance in mortality in India. PMID:21305396

Sex-specific modulation of juvenile social play by vasopressin.

PubMed

Veenema, Alexa H; Bredewold, Remco; De Vries, Geert J

2013-11-01

Social play activities among juveniles are thought to contribute to the development of social and emotional skills in humans and animals. Conversely, social play deficits are observed in developmental neuropsychiatric disorders. Importantly, many of these disorders show sex differences in incidence, course of the disease, and severity of symptoms. We hypothesized that sex differences in the neural systems controlling social behavior can contribute to these differences. We therefore studied the involvement of the sexually dimorphic vasopressin and oxytocin systems, which have been implicated in these disorders, in juvenile social play behavior. Single-housed 5-week-old juvenile male and female rats were exposed in their home cage to an age-and sex-matched novel conspecific for 10 min, and social play behaviors were recorded. We found no consistent sex differences in duration or elements of social play in vehicle-treated rats. However, intracerebroventricular injection of the specific vasopressin 1a receptor (V1aR) antagonist (CH2)5Tyr(Me(2))AVP significantly reduced social play behaviors in males while increasing them in females. Intracerebroventricular injection of the specific oxytocin receptor antagonist des-Gly-NH2,d(CH2)5[Tyr(Me)(2),Thr(4)]OVT did not alter social play in either sex. To locate the effects of V1aR blockade on social play, we targeted the lateral septum, a sexually dimorphic brain region showing denser vasopressin fibers in males than in females and an abundant expression of V1aR in both sexes. Surprisingly, blockade of V1aR in the lateral septum increased social play behaviors in males, but decreased them in females. These findings suggest sex- and brain region-specific roles for vasopressin in the regulation of social play behavior in juvenile rats. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sex-specific modulation of juvenile social play by vasopressin

PubMed Central

Veenema, Alexa H.; Bredewold, Remco; De Vries, Geert J.

2013-01-01

SUMMARY Social play activities among juveniles are thought to contribute to the development of social and emotional skills in humans and animals. Conversely, social play deficits are observed in developmental neuropsychiatric disorders. Importantly, many of these disorders show sex differences in incidence, course of the disease, and severity of symptoms. We hypothesized that sex differences in the neural systems controlling social behavior can contribute to these differences. We therefore studied the involvement of the sexually dimorphic vasopressin and oxytocin systems, which have been implicated in these disorders, in juvenile social play behavior. Single-housed 5-week-old juvenile male and female rats were exposed to an unknown age-and sex-matched conspecific for 10 min in their home cage and social play behaviors were recorded. We found no consistent sex differences in level or elements of social play in vehicle-treated rats. However, intracerebroventricular injection of the specific vasopressin 1a receptor (V1aR) antagonist (CH2)5Tyr(Me2) AVP significantly reduced social play behaviors in males, while increasing them in females. Intracerebroventricular injection of the specific oxytocin receptor antagonist des-Gly-NH2,d(CH2)5[Tyr(Me)2,Thr4]OVT did not alter social play in either sex. To locate the effects of V1aR blockade on social play, we targeted the lateral septum, a sexually dimorphic brain region showing denser vasopressin fibers in males than in females and abundant expression of V1aR in both sexes. Surprisingly, blockade of V1aR in the lateral septum increased social play behaviors in males, but decreased them in females. These findings suggest sex- and brain region-specific roles for vasopressin in the regulation of social play behavior in juvenile rats. PMID:23838102

Sex- and Tissue-specific Functions of Drosophila Doublesex Transcription Factor Target Genes

PubMed Central

Clough, Emily; Jimenez, Erin; Kim, Yoo-Ah; Whitworth, Cale; Neville, Megan C.; Hempel, Leonie; Pavlou, Hania J.; Chen, Zhen-Xia; Sturgill, David; Dale, Ryan; Smith, Harold E.; Przytycka, Teresa M.; Goodwin, Stephen F.; Van Doren, Mark; Oliver, Brian

2014-01-01

Primary sex determination “switches” evolve rapidly, but Doublesex (DSX) related transcription factors (DMRTs) act downstream of these switches to control sexual development in most animal species. Drosophila dsx encodes female- and male-specific isoforms (DSXF and DSXM), but little is known about how dsx controls sexual development, whether DSXF and DSXM bind different targets, or how DSX proteins direct different outcomes in diverse tissues. We undertook genome-wide analyses to identify DSX targets using in vivo occupancy, binding site prediction, and evolutionary conservation. We find that DSXF and DSXM bind thousands of the same targets in multiple tissues in both sexes, yet these targets have sex- and tissue-specific functions. Interestingly, DSX targets show considerable overlap with targets identified for mouse DMRT1. DSX targets include transcription factors and signaling pathway components providing for direct and indirect regulation of sex-biased expression. PMID:25535918

Methods of Suicide by Age: Sex and Race Differences among the Young and Old.

ERIC Educational Resources Information Center

McIntosh, John L.; Santos, John F.

1986-01-01

Annual official statistics for specific methods of suicide (firearms, hanging, poisons) by age for different sex and racial groups (Whites, Blacks, non-Whites excluding Black) were examined from 1960 to 1978. Comparisons among the age-sex-race groups, along with trends over time and differences in the methods employed, were noted. (Author/ABL)

National and state-specific health insurance disparities for adults in same-sex relationships.

PubMed

Gonzales, Gilbert; Blewett, Lynn A

2014-02-01

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

Age of Sexual Debut and Physical Dating Violence Victimization: Sex Differences among US High School Students

ERIC Educational Resources Information Center

Ihongbe, Timothy O.; Cha, Susan; Masho, Saba W.

2017-01-01

Background: Research has shown that early age of sexual debut is associated with physical dating violence (PDV), but sex-specific associations are sparse. We estimated the prevalence of PDV victimization in high school students who have initiated sexual intercourse and examined sex-specific association between age of sexual debut and PDV…

Avian sex, sex chromosomes, and dosage compensation in the age of genomics.

PubMed

Graves, Jennifer A Marshall

2014-04-01

Comparisons of the sex chromosome systems in birds and mammals are widening our view and deepening our understanding of vertebrate sex chromosome organization, function, and evolution. Birds have a very conserved ZW system of sex determination in which males have two copies of a large, gene-rich Z chromosome, and females have a single Z and a female-specific W chromosome. The avian ZW system is quite the reverse of the well-studied mammalian XY chromosome system, and evolved independently from different autosomal blocs. Despite the different gene content of mammal and bird sex chromosomes, there are many parallels. Genes on the bird Z and the mammal X have both undergone selection for male-advantage functions, and there has been amplification of male-advantage genes and accumulation of LINEs. The bird W and mammal Y have both undergone extensive degradation, but some birds retain early stages and some mammals terminal stages of the process, suggesting that the process is more advanced in mammals. Different sex-determining genes, DMRT1 and SRY, define the ZW and XY systems, but DMRT1 is involved in downstream events in mammals. Birds show strong cell autonomous specification of somatic sex differences in ZZ and ZW tissue, but there is growing evidence for direct X chromosome effects on sexual phenotype in mammals. Dosage compensation in birds appears to be phenotypically and molecularly quite different from X inactivation, being partial and gene-specific, but both systems use tools from the same molecular toolbox and there are some signs that galliform birds represent an early stage in the evolution of a coordinated system.

Confidence mediates the sex difference in mental rotation performance.

PubMed

Estes, Zachary; Felker, Sydney

2012-06-01

On tasks that require the mental rotation of 3-dimensional figures, males typically exhibit higher accuracy than females. Using the most common measure of mental rotation (i.e., the Mental Rotations Test), we investigated whether individual variability in confidence mediates this sex difference in mental rotation performance. In each of four experiments, the sex difference was reliably elicited and eliminated by controlling or manipulating participants' confidence. Specifically, confidence predicted performance within and between sexes (Experiment 1), rendering confidence irrelevant to the task reliably eliminated the sex difference in performance (Experiments 2 and 3), and manipulating confidence significantly affected performance (Experiment 4). Thus, confidence mediates the sex difference in mental rotation performance and hence the sex difference appears to be a difference of performance rather than ability. Results are discussed in relation to other potential mediators and mechanisms, such as gender roles, sex stereotypes, spatial experience, rotation strategies, working memory, and spatial attention.

Sex differences in the neural substrates of spatial working memory during adolescence are not mediated by endogenous testosterone.

PubMed

Alarcón, Gabriela; Cservenka, Anita; Fair, Damien A; Nagel, Bonnie J

2014-12-17

Adolescence is a developmental period characterized by notable changes in behavior, physical attributes, and an increase in endogenous sex steroid hormones, which may impact cognitive functioning. Moreover, sex differences in brain structure are present, leading to differences in neural function and cognition. Here, we examine sex differences in performance and blood oxygen level-dependent (BOLD) activation in a sample of adolescents during a spatial working memory (SWM) task. We also examine whether endogenous testosterone levels mediate differential brain activity between the sexes. Adolescents between ages 10 and 16 years completed a SWM functional magnetic resonance imaging (fMRI) task, and serum hormone levels were assessed within seven days of scanning. While there were no sex differences in task performance (accuracy and reaction time), differences in BOLD response between girls and boys emerged, with girls deactivating brain regions in the default mode network and boys showing increased response in SWM-related brain regions of the frontal cortex. These results suggest that adolescent boys and girls adopted distinct neural strategies, while maintaining spatial cognitive strategies that facilitated comparable cognitive performance of a SWM task. A nonparametric bootstrapping procedure revealed that testosterone did not mediate sex-specific brain activity, suggesting that sex differences in BOLD activation during SWM may be better explained by other factors, such as early organizational effects of sex steroids or environmental influences. Elucidating sex differences in neural function and the influence of gonadal hormones can serve as a basis of comparison for understanding sexually dimorphic neurodevelopment and inform sex-specific psychopathology that emerges in adolescence. Copyright © 2014 Elsevier B.V. All rights reserved.

Sex-biased transcriptome divergence along a latitudinal gradient.

PubMed

Allen, Scott L; Bonduriansky, Russell; Sgro, Carla M; Chenoweth, Stephen F

2017-03-01

Sex-dependent gene expression is likely an important genomic mechanism that allows sex-specific adaptation to environmental changes. Among Drosophila species, sex-biased genes display remarkably consistent evolutionary patterns; male-biased genes evolve faster than unbiased genes in both coding sequence and expression level, suggesting sex differences in selection through time. However, comparatively little is known of the evolutionary process shaping sex-biased expression within species. Latitudinal clines offer an opportunity to examine how changes in key ecological parameters also influence sex-specific selection and the evolution of sex-biased gene expression. We assayed male and female gene expression in Drosophila serrata along a latitudinal gradient in eastern Australia spanning most of its endemic distribution. Analysis of 11 631 genes across eight populations revealed strong sex differences in the frequency, mode and strength of divergence. Divergence was far stronger in males than females and while latitudinal clines were evident in both sexes, male divergence was often population specific, suggesting responses to localized selection pressures that do not covary predictably with latitude. While divergence was enriched for male-biased genes, there was no overrepresentation of X-linked genes in males. By contrast, X-linked divergence was elevated in females, especially for female-biased genes. Many genes that diverged in D. serrata have homologs also showing latitudinal divergence in Drosophila simulans and Drosophila melanogaster on other continents, likely indicating parallel adaptation in these distantly related species. Our results suggest that sex differences in selection play an important role in shaping the evolution of gene expression over macro- and micro-ecological spatial scales. © 2017 John Wiley & Sons Ltd.

Refined genetic maps reveal sexual dimorphism in human meiotic recombination at multiple scales

NASA Astrophysics Data System (ADS)

Bhérer, Claude; Campbell, Christopher L.; Auton, Adam

2017-04-01

In humans, males have lower recombination rates than females over the majority of the genome, but the opposite is usually true near the telomeres. These broad-scale differences have been known for decades, yet little is known about differences at the fine scale. By combining data sets, we have collected recombination events from over 100,000 meioses and have constructed sex-specific genetic maps at a previously unachievable resolution. Here we show that, although a substantial fraction of the genome shows some degree of sexually dimorphic recombination, the vast majority of hotspots are shared between the sexes, with only a small number of putative sex-specific hotspots. Wavelet analysis indicates that most of the differences can be attributed to the fine scale, and that variation in rate between the sexes can mostly be explained by differences in hotspot magnitude, rather than location. Nonetheless, known recombination-associated genomic features, such as THE1B repeat elements, show systematic differences between the sexes.

Sex-specific markers developed by next-generation sequencing confirmed an XX/XY sex determination system in bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix).

PubMed

Liu, Haiyang; Pang, Meixia; Yu, Xiaomu; Zhou, Ying; Tong, Jingou; Fu, Beide

2018-01-05

Sex-specific markers are powerful tools for identifying sex-determination system in various animals. Bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix) are two of the most important edible fish in Asia, which have a long juvenility period that can lasts for 4-5 years. In this study, we found one sex-specific marker by next-generation sequencing together with bioinformatics analysis in bighead carp. The male-specific markers were used to perform molecular sexing in the progenies of artificial gynogenetic diploids and found all progenies (n = 160) were females. Meanwhile, around 1 : 1 sex ratio was observed in a total of 579 juvenile offspring from three other families. To further extend the male-specific region, we performed genome walking and got a male-specific sequence of 8,661 bp. Five pairs of primers were designed and could be used to efficiently distinguish males from females in bighead carp and silver carp. The development of these male-specific markers and results of their molecular sexing in different populations provide strong evidence for a sex determination system of female homogametry or male heterogametry (XX/XY) in bighead carp and silver carp. To the best of our knowledge, this is the first report of effective sex-specific markers in these two large carp species. © The Author(s) 2018. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Sex differences in the acute in vivo effects of different human SP-A variants on the mouse alveolar macrophage proteome

PubMed Central

Phelps, David S.; Umstead, Todd M.; Floros, Joanna

2014-01-01

Surfactant protein A (SP-A) is involved in lung innate immunity. Humans have two SP-A genes, SFTPA1 and SFTPA2, each with several variants. We examined the in vivo effects of treatment with specific SP-A variants on the alveolar macrophage (AM) proteome from SP-A knockout (KO) mice. KO mice received either SP-A1, SP-A2, or both. AM were collected and their proteomes examined with 2D-DIGE. We identified 90 proteins and categorized them as related to actin/cytoskeleton, oxidative stress, protease balance/chaperones, regulation of inflammation, and regulatory/developmental processes. SP-A1 and SP-A2 had different effects on the AM proteome and these effects differed between sexes. In males more changes occurred in the oxidative stress, protease/chaperones, and inflammation groups with SP-A2 treatment than with SP-A1. In females most SP-A1-induced changes were in the actin/cytoskeletal and oxidative stress groups. We conclude that after acute SP-A1 and SP-A2 treatment, sex-specific differences were observed in the AM proteomes from KO mice, and that these sex differences differ in response to SP-A1 and SP-A2. Females are more responsive to SP-A1, whereas the gene-specific differences in males were minimal. These observations not only demonstrate the therapeutic potential of exogenous SP-A, but also illustrate sex- and gene-specific differences in the response to it. PMID:24954098

Prognostic Importance of Sex-Specific Cardiac Troponin T 99(th) Percentiles in Suspected Acute Coronary Syndrome.

PubMed

Eggers, Kai M; Jernberg, Tomas; Lindahl, Bertil

2016-08-01

Cardiac troponin levels differ between the sexes, with higher values commonly seen in men. The use of sex-specific troponin thresholds is, thus, subject of an ongoing debate. We assessed whether sex-specific cardiac troponin T (cTnT) 99(th) percentiles would improve risk prediction in patients admitted to Swedish coronary care units due to suspected acute coronary syndrome. In this retrospective register-based study (48,250 patients), we investigated the prediction of all-cause mortality and the composite of cardiovascular death or nonfatal myocardial infarction within 1 year using the single 99(th) cTnT percentile (>14 ng/L) or sex-specific cTnT 99(th) percentiles (>16/9 ng/L). A total of 1078 men (3.0%) with cTnT 15-16 ng/L and 1854 women (8.4%) with cTnT 10-14 ng/L would have been reclassified regarding their cTnT status by the means of sex-specific 99(th) percentiles. The prevalence of cardiovascular risk factors and crude event rates increased across higher cTnT strata in both men and women. Multivariable-adjusted Cox models, however, did not demonstrate better risk prediction by sex-specific 99(th) percentiles. Assessing cTnT as a continuous variable demonstrated an increase in multivariable-adjusted risk starting at levels around 10-12 ng/L in both men and women. We found no evidence supporting the use of sex-specific cTnT 99(th) percentiles in men and women admitted because of suspected acute coronary syndrome. This likely depends on sex-specific differences in disease mechanisms associated with small cTnT elevations. From a pragmatic perspective, a single cTnT cutoff slightly below 14 ng/L seems to be preferable as a threshold for medical decision-making. Copyright © 2016 Elsevier Inc. All rights reserved.

Sex Steroid Signaling: Implications for Lung Diseases

PubMed Central

Sathish, Venkatachalem; Martin, Yvette N.; Prakash, Y.S.

2015-01-01

There is increasing recognition that the sex hormones (estrogen, progesterone, and testosterone) have biological and pathophysiological actions in peripheral, non-reproductive organs, including the lung. Clinically, sex differences in the incidence, morbidity and mortality of lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, lung cancer and pulmonary hypertension have been noted, although intrinsic sex differences vs. the roles of sex steroids are still not well-understood. Accordingly, it becomes important to ask the following questions: 1) Which sex steroids are involved? 2) How do they affect different components of the lung under normal circumstances? 3) How does sex steroid signaling change in or contribute to lung disease, and in this regard, are sex steroids detrimental or beneficial? As our understanding of sex steroid signaling in the lung improves, it is important to consider whether such information can be used to develop new therapeutic strategies to target lung diseases, perhaps in both sexes or in a sex-specific manner. In this review, we focus on the basics of sex steroid signaling, and the current state of knowledge regarding how they influence structure and function of specific lung components across the life span and in the context of some important lung diseases. We then summarize the potential for sex steroids as useful biomarkers and therapeutic targets in these lung diseases as a basis for future translational research in the area of gender and individualized medicine. PMID:25595323

Sex differences in gut microbiota in patients with major depressive disorder.

PubMed

Chen, Jian-Jun; Zheng, Peng; Liu, Yi-Yun; Zhong, Xiao-Gang; Wang, Hai-Yang; Guo, Yu-Jie; Xie, Peng

2018-01-01

Our previous studies found that disturbances in gut microbiota might have a causative role in the onset of major depressive disorder (MDD). The aim of this study was to investigate whether there were sex differences in gut microbiota in patients with MDD. First-episode drug-naïve MDD patients and healthy controls were included. 16S rRNA gene sequences extracted from the fecal samples of the included subjects were analyzed. Principal-coordinate analysis and partial least squares-discriminant analysis were used to assess whether there were sex-specific gut microbiota. A random forest algorithm was used to identify the differential operational taxonomic units. Linear discriminant-analysis effect size was further used to identify the dominant sex-specific phylotypes responsible for the differences between MDD patients and healthy controls. In total, 57 and 74 differential operational taxonomic units responsible for separating female and male MDD patients from their healthy counterparts were identified. Compared with their healthy counterparts, increased Actinobacteria and decreased Bacteroidetes levels were found in female and male MDD patients, respectively. The most differentially abundant bacterial taxa in female and male MDD patients belonged to phyla Actinobacteria and Bacteroidia, respectively. Meanwhile, female and male MDD patients had different dominant phylotypes. These results demonstrated that there were sex differences in gut microbiota in patients with MDD. The suitability of Actinobacteria and Bacteroidia as the sex-specific biomarkers for diagnosing MDD should be further explored.

Sex-Differences, Handedness, and Lateralization in the Iowa Gambling Task

PubMed Central

Singh, Varsha

2016-01-01

In a widely used decision-making task, the Iowa Gambling Task (IGT), male performance is observed to be superior to that of females, and is attributed to right lateralization (i.e., right hemispheric dominance). It is as yet unknown whether sex-differences in affect and motor lateralization have implications for sex-specific lateralization in the IGT, and specifically, whether sex-difference in performance in the IGT changes with right-handedness or with affect lateralization (decision valence, and valence-directed motivation). The present study (N = 320; 160 males) examined the effects of right-handedness (right-handedness vs. non-right-handedness) as a measure of motor lateralization, decision valence (reward vs. punishment IGT), and valence-directedness of task motivation (valence-directed vs. non-directed instructions), as measures of affective lateralization on IGT decision making. Analyses of variance revealed that both male and female participants showed valence-induced inconsistencies in advantageous decision-making; however, right-handed females made more disadvantageous decisions in a reward IGT. These results suggest that IGT decision-making may be largely right-lateralized in right-handed males, and show that sex and lateralized differences (motor and affect) have implications for sex-differences in IGT decision-making. Implications of the results are discussed with reference to lateralization and sex-differences in cognition. PMID:27303316

Sex, Intelligence and Educational Achievement in a National Cohort of over 175,000 11-Year-Old Schoolchildren in England

ERIC Educational Resources Information Center

Calvin, Catherine M.; Fernandes, Cres; Smith, Pauline; Visscher, Peter M.; Deary, Ian J.

2010-01-01

General cognitive ability ("g") does not explain sex differences in academic test performance by the end of compulsory education. Instead, individual differences in specific reasoning abilities, after removing the effects of "g," may contribute to the observed gender gaps. Associations between general or specific cognitive…

Functional neuroimaging of sex differences in autobiographical memory recall in depression.

PubMed

Young, K D; Bodurka, J; Drevets, W C

2017-11-01

Females are more likely than males to develop major depressive disorder (MDD). The current study used fMRI to compare the neural correlates of autobiographical memory (AM) recall between males and females diagnosed with MDD. AM overgenerality is a persistent cognitive deficit in MDD, the magnitude of which is correlated with depressive severity only in females. Delineating the neurobiological correlates of this deficit may elucidate the nature of sex-differences in the diathesis for developing MDD. Participants included unmedicated males and females diagnosed with MDD (n = 20/group), and an age and sex matched healthy control group. AM recall in response to positive, negative, and neutral cue words was compared with a semantic memory task. The behavioral properties of AMs did not differ between MDD males and females. In contrast, main effects of sex on cerebral hemodynamic activity were observed in left dorsolateral prefrontal cortex and parahippocampal gyrus during recall of positive specific memories, and middle prefrontal cortex (mPFC), and precuneus during recall of negative specific memories. Moreover, main effects of diagnosis on regional hemodynamic activity were observed in left ventrolateral prefrontal cortex and mPFC during positive specific memory recall, and dorsal anterior cingulate cortex during negative specific memory recall. Sex × diagnosis interactions were evident in the dorsomedial prefrontal cortex, caudate, and precuneus during positive memory recall, and in the posterior cingulate cortex, insula, precuneus and thalamus during negative specific memory recall. The differential hemodynamic changes conceivably may reflect sex-specific cognitive strategies during recall of AMs irrespective of the phenomenological properties of those memories.

Sex-specific effects of cardiovascular risk factors on endothelium-dependent dilation and endothelin activity in middle-aged women and men.

PubMed

Brar, Vijaywant; Gill, Sartaj; Cardillo, Carmine; Tesauro, Manfredi; Panza, Julio A; Campia, Umberto

2015-01-01

Healthy middle-aged postmenopausal women have higher endothelium-dependent dilation and lower vasoconstrictor activity of endothelin-1 than men. Whether these sex-specific differences extend to patients with cardiovascular risk factors has not been investigated. The current study aimed to determine whether, in patients with cardiovascular risk factors, sex-specific differences exist in endothelium-dependent dilation and endothelin-1 activity. Forearm blood flow responses were measured by strain-gauge plethysmography during the intra-arterial infusion of acetylcholine, sodium nitroprusside, and the selective endothelin type A receptor blocker BQ-123 in 50 women and 64 men with cardiovascular risk factors. Acetylcholine and sodium nitroprusside induced a significant vasodilation in women and men alike (p < 0.01 for both). Also BQ-123 caused a significant vasodilation (p < 0.001) in both groups. The vasodilator response to acetylcholine was greater in women compared to men; however there were no differences in the response to sodium nitroprusside and BQ-123 (p = NS for both) between the two sex groups. Middle-aged women with cardiovascular risk factors have significantly higher endothelium-dependent dilation than middle-aged men; however, vascular endothelin 1 activity is similar in the two groups. These findings suggest that the presence of cardiovascular risk factors is associated with sex-specific effects on endothelium-dependent dilation but not on endothelin 1 activity. Further study is needed to confirm our findings and to characterize the mechanisms underlying this sex-specific regulation of endothelial function.

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

PubMed

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

2012-02-15

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

Sex-specific differences in hyperoxic lung injury in mice: Implications for acute and chronic lung disease in humans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lingappan, Krithika, E-mail: lingappa@bcm.edu; Jiang, Weiwu; Wang, Lihua

Sex-specific differences in pulmonary morbidity in humans are well documented. Hyperoxia contributes to lung injury in experimental animals and humans. The mechanisms responsible for sex differences in the susceptibility towards hyperoxic lung injury remain largely unknown. In this investigation, we tested the hypothesis that mice will display sex-specific differences in hyperoxic lung injury. Eight week-old male and female mice (C57BL/6J) were exposed to 72 h of hyperoxia (FiO{sub 2} > 0.95). After exposure to hyperoxia, lung injury, levels of 8-iso-prostaglandin F{sub 2} alpha (8-iso-PGF 2α) (LC–MS/MS), apoptosis (TUNEL) and inflammatory markers (suspension bead array) were determined. Cytochrome P450 (CYP)1A expressionmore » in the lung was assessed using immunohistochemistry and western blotting. After exposure to hyperoxia, males showed greater lung injury, neutrophil infiltration and apoptosis, compared to air-breathing controls than females. Pulmonary 8-iso-PGF 2α levels were higher in males than females after hyperoxia exposure. Sexually dimorphic increases in levels of IL-6 (F > M) and VEGF (M > F) in the lungs were also observed. CYP1A1 expression in the lung was higher in female mice compared to males under hyperoxic conditions. Overall, our results support the hypothesis that male mice are more susceptible than females to hyperoxic lung injury and that differences in inflammatory and oxidative stress markers contribute to these sex-specific dimorphic effects. In conclusion, this paper describes the establishment of an animal model that shows sex differences in hyperoxic lung injury in a temporal manner and thus has important implications for lung diseases mediated by hyperoxia in humans. - Highlights: • Male mice were more susceptible to hyperoxic lung injury than females. • Sex differences in inflammatory markers were observed. • CYP1A expression was higher in females after hyperoxia exposure.« less

Sex Differences in the Association between Foetal Growth and Child Attention at Age Four: Specific Vulnerability of Girls

ERIC Educational Resources Information Center

Murray, Elizabeth; Matijasevich, Alicia; Santos, Iná S.; Barros, Aluísio J. D.; Anselmi, Luciana; Barros, Fernando C.; Stein, Alan

2015-01-01

Background: Recent evidence suggests that impaired foetal growth may provide an early indication of increased risk of child attention problems. However, despite both foetal growth and child attention problems differing by sex, few studies have examined sex differences in this association. Furthermore, no studies have been conducted in low- and…

Sex Differences in Magical Ideation: A Community-Based Twin Study

PubMed Central

Karcher, Nicole R.; Slutske, Wendy S.; Kerns, John G.; Piasecki, Thomas M.; Martin, Nicholas G.

2014-01-01

Two questions regarding sex differences in magical ideation were investigated in this study: (1) whether there are mean level sex differences on the Magical Ideation Scale (MIS), and (2) whether there are quantitative and/or qualitative sex differences in the genetic contributions to variation on this scale. These questions were evaluated using data obtained from a large community sample of adult Australian twins (N=4,355) that included opposite-sex pairs. Participants completed a modified 15-item version of the MIS within a larger assessment battery. Women reported both higher means and variability on the MIS than men; this was also observed within families (in opposite-sex twin pairs). Biometric modeling indicated that the proportion of variation in MIS scores due to genetic influences (indicating quantitative sex differences) and the specific latent genetic contributions to this variation (indicating qualitative sex differences) were the same in men and women. These findings clarify the nature of sex differences in magical ideation and point to avenues for future research. PMID:24364500

Clinical epidemiology of Alzheimer's disease: assessing sex and gender differences.

PubMed

Mielke, Michelle M; Vemuri, Prashanthi; Rocca, Walter A

2014-01-01

With the aging of the population, the burden of Alzheimer's disease (AD) is rapidly expanding. More than 5 million people in the US alone are affected with AD and this number is expected to triple by 2050. While men may have a higher risk of mild cognitive impairment (MCI), an intermediate stage between normal aging and dementia, women are disproportionally affected with AD. One explanation is that men may die of competing causes of death earlier in life, so that only the most resilient men may survive to older ages. However, many other factors should also be considered to explain the sex differences. In this review, we discuss the differences observed in men versus women in the incidence and prevalence of MCI and AD, in the structure and function of the brain, and in the sex-specific and gender-specific risk and protective factors for AD. In medical research, sex refers to biological differences such as chromosomal differences (eg, XX versus XY chromosomes), gonadal differences, or hormonal differences. In contrast, gender refers to psychosocial and cultural differences between men and women (eg, access to education and occupation). Both factors play an important role in the development and progression of diseases, including AD. Understanding both sex- and gender-specific risk and protective factors for AD is critical for developing individualized interventions for the prevention and treatment of AD.

Clinical epidemiology of Alzheimer’s disease: assessing sex and gender differences

PubMed Central

Mielke, Michelle M; Vemuri, Prashanthi; Rocca, Walter A

2014-01-01

With the aging of the population, the burden of Alzheimer’s disease (AD) is rapidly expanding. More than 5 million people in the US alone are affected with AD and this number is expected to triple by 2050. While men may have a higher risk of mild cognitive impairment (MCI), an intermediate stage between normal aging and dementia, women are disproportionally affected with AD. One explanation is that men may die of competing causes of death earlier in life, so that only the most resilient men may survive to older ages. However, many other factors should also be considered to explain the sex differences. In this review, we discuss the differences observed in men versus women in the incidence and prevalence of MCI and AD, in the structure and function of the brain, and in the sex-specific and gender-specific risk and protective factors for AD. In medical research, sex refers to biological differences such as chromosomal differences (eg, XX versus XY chromosomes), gonadal differences, or hormonal differences. In contrast, gender refers to psychosocial and cultural differences between men and women (eg, access to education and occupation). Both factors play an important role in the development and progression of diseases, including AD. Understanding both sex- and gender-specific risk and protective factors for AD is critical for developing individualized interventions for the prevention and treatment of AD. PMID:24470773

Selective sex differences in declarative memory.

PubMed

Maitland, Scott B; Herlitz, Agneta; Nyberg, Lars; Bäckman, Lars; Nilsson, Lars-Göran

2004-10-01

Sex invariance of a six-factor, higher order model of declarative memory (two second-order factors: episodic and semantic memory; and four first-order factors: recall, recognition, fluency, and knowledge) was established for 1,796 participants (35-85 years). Metric invariance of first- and second-order factor loadings across sex was demonstrated. At the second-order level, a female advantage was observed for both episodic and semantic memory. At the first-order level, sex differences in episodic memory were apparent for both recall and recognition, whereas the differences in semantic memory were driven by a female superiority in fluency. Additional tests of sex differences in three age groups (35-50, 55-65, and 70-85 years of age) indicated that the female superiority in declarative memory diminished with advancing age. The factor-specific sex differences are discussed in relation to sex differences in hippocampal function.

Recent Sex Chromosome Divergence despite Ancient Dioecy in the Willow Salix viminalis

PubMed Central

Pucholt, Pascal; Wright, Alison E.; Conze, Lei Liu; Mank, Judith E.; Berlin, Sofia

2017-01-01

Abstract Sex chromosomes can evolve when recombination is halted between a pair of chromosomes, and this can lead to degeneration of the sex-limited chromosome. In the early stages of differentiation sex chromosomes are homomorphic, and even though homomorphic sex chromosomes are very common throughout animals and plants, we know little about the evolutionary forces shaping these types of sex chromosomes. We used DNA- and RNA-Seq data from females and males to explore the sex chromosomes in the female heterogametic willow, Salix viminalis, a species with ancient dioecy but with homomorphic sex chromosomes. We detected no major sex differences in read coverage in the sex determination (SD) region, indicating that the W region has not significantly degenerated. However, single nucleotide polymorphism densities in the SD region are higher in females compared with males, indicating very recent recombination suppression, followed by the accumulation of sex-specific single nucleotide polymorphisms. Interestingly, we identified two female-specific scaffolds that likely represent W-chromosome-specific sequence. We show that genes located in the SD region display a mild excess of male-biased expression in sex-specific tissue, and we use allele-specific gene expression analysis to show that this is the result of masculinization of expression on the Z chromosome rather than degeneration of female-expression on the W chromosome. Together, our results demonstrate that insertion of small DNA fragments and accumulation of sex-biased gene expression can occur before the detectable decay of the sex-limited chromosome. PMID:28453634

Does the silver moss Bryum argenteum exhibit sex-specific patterns in vegetative growth rate, asexual fitness or prezygotic reproductive investment?

PubMed Central

Horsley, Kimberly; Stark, Lloyd R.; McLetchie, D. Nicholas

2011-01-01

Background and Aims Expected life history trade-offs associated with sex differences in reproductive investment are often undetected in seed plants, with the difficulty arising from logistical issues of conducting controlled experiments. By controlling genotype, age and resource status of individuals, a bryophyte was assessed for sex-specific and location-specific patterns of vegetative, asexual and sexual growth/reproduction across a regional scale. Methods Twelve genotypes (six male, six female) of the dioecious bryophyte Bryum argenteum were subcultured to remove environmental effects, regenerated asexually to replicate each genotype 16 times, and grown over a period of 92 d. Plants were assessed for growth rates, asexual and sexual reproductive traits, and allocation to above- and below-ground regenerative biomass. Key Results The degree of sexual versus asexual reproductive investment appears to be under genetic control, with three distinct ecotypes found in this study. Protonemal growth rate was positively correlated with asexual reproduction and sexual reproduction, whereas asexual reproduction was negatively correlated (appeared to trade-off) with vegetative growth (shoot production). No sex-specific trade-offs were detected. Female sex-expressing shoots were longer than males, but the sexes did not differ in growth traits, asexual traits, sexual induction times, or above- and below-ground biomass. Males, however, had much higher rates of inflorescence production than females, which translated into a significantly higher (24x) prezygotic investment for males relative to females. Conclusions Evidence for three distinct ecotypes is presented for a bryophyte based on regeneration traits. Prior to zygote production, the sexes of this bryophyte did not differ in vegetative growth traits but significantly differed in reproductive investment, with the latter differences potentially implicated in the strongly biased female sex ratio. The disparity between males and females for prezygotic reproductive investment is the highest known for bryophytes. PMID:21320878

Sexually antagonistic selection on genetic variation underlying both male and female same-sex sexual behavior.

PubMed

Berger, David; You, Tao; Minano, Maravillas R; Grieshop, Karl; Lind, Martin I; Arnqvist, Göran; Maklakov, Alexei A

2016-05-13

Intralocus sexual conflict, arising from selection for different alleles at the same locus in males and females, imposes a constraint on sex-specific adaptation. Intralocus sexual conflict can be alleviated by the evolution of sex-limited genetic architectures and phenotypic expression, but pleiotropic constraints may hinder this process. Here, we explored putative intralocus sexual conflict and genetic (co)variance in a poorly understood behavior with near male-limited expression. Same-sex sexual behaviors (SSBs) generally do not conform to classic evolutionary models of adaptation but are common in male animals and have been hypothesized to result from perception errors and selection for high male mating rates. However, perspectives incorporating sex-specific selection on genes shared by males and females to explain the expression and evolution of SSBs have largely been neglected. We performed two parallel sex-limited artificial selection experiments on SSB in male and female seed beetles, followed by sex-specific assays of locomotor activity and male sex recognition (two traits hypothesized to be functionally related to SSB) and adult reproductive success (allowing us to assess fitness consequences of genetic variance in SSB and its correlated components). Our experiments reveal both shared and sex-limited genetic variance for SSB. Strikingly, genetically correlated responses in locomotor activity and male sex-recognition were associated with sexually antagonistic fitness effects, but these effects differed qualitatively between male and female selection lines, implicating intralocus sexual conflict at both male- and female-specific genetic components underlying SSB. Our study provides experimental support for the hypothesis that widespread pleiotropy generates pervasive intralocus sexual conflict governing the expression of SSBs, suggesting that SSB in one sex can occur due to the expression of genes that carry benefits in the other sex.

Legal recognition of same-sex couples and family formation.

PubMed

Trandafir, Mircea

2015-02-01

It has long been debated how legalizing same-sex marriage would affect (different-sex) family formation. In this article, I use data on OECD member countries for the period 1980-2009 to examine the effects of the legal recognition of same-sex couples (through marriage or an alternative institution) on different-sex marriage, divorce, and extramarital births. Estimates from difference-in-difference models indicate that the introduction of same-sex marriage or of alternative institutions has no negative effects on family formation. These findings are robust to a multitude of specification checks, including the construction of counterfactuals using the synthetic control method. In addition, the country-by-country case studies provide evidence of homogeneity of the estimated effects.

Sex-Specific Arrival Times on the Breeding Grounds: Hybridizing Migratory Skuas Provide Empirical Support for the Role of Sex Ratios.

PubMed

Lisovski, Simeon; Fröhlich, Anne; von Tersch, Matthew; Klaassen, Marcel; Peter, Hans-Ulrich; Ritz, Markus S

2016-04-01

In migratory animals, protandry (earlier arrival of males on the breeding grounds) prevails over protogyny (females preceding males). In theory, sex differences in timing of arrival should be driven by the operational sex ratio, shifting toward protogyny in female-biased populations. However, empirical support for this hypothesis is, to date, lacking. To test this hypothesis, we analyzed arrival data from three populations of the long-distance migratory south polar skua (Catharacta maccormicki). These populations differed in their operational sex ratio caused by the unidirectional hybridization of male south polar skuas with female brown skuas (Catharacta antarctica lonnbergi). We found that arrival times were protandrous in allopatry, shifting toward protogyny in female-biased populations when breeding in sympatry. This unique observation is consistent with theoretical predictions that sex-specific arrival times should be influenced by sex ratio and that protogyny should be observed in populations with female-biased operational sex ratio.

Host Responses to the Pathogen Mycobacterium avium subsp. paratuberculosis and Beneficial Microbes Exhibit Host Sex Specificity

PubMed Central

McMahon, K. Wyatt; Chang, David; Brashears, Mindy M.

2014-01-01

Differences between microbial pathogenesis in male and female hosts are well characterized in disease conditions connected to sexual transmission. However, limited biological insight is available on variances attributed to sex specificity in host-microbe interactions, and it is most often a minimized variable outside these transmission events. In this work, we studied two gut microbes—a pathogen, Mycobacterium avium subsp. paratuberculosis, and a probiotic, Lactobacillus animalis NP-51—and the interaction between each agent and the male and female gastrointestinal systems. This trial was conducted in BALB/c mice (n = 5 per experimental group and per sex at a given time point), with analysis at four time points over 180 days. Host responses to M. avium subsp. paratuberculosis and L. animalis were sensitive to sex. Cytokines that were significantly different (P ≤ 0.05) between the sexes included interleukin-1α/β (IL-1α/β), IL-17, IL-6, IL-10, IL-12, and gamma interferon (IFN-γ) and were dependent on experimental conditions. However, granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), and IL-13/23 showed no sex specificity. A metabolomics study indicated a 0.5- to 2.0-fold (log2 scale) increase in short-chain fatty acids (butyrate and acetate) in males and greater increases in o-phosphocholine or histidine from female colon tissues; variances distinct to each sex were observed with age or long-term probiotic consumption. Two genera, Staphylococcus and Roseburia, were consistently overrepresented in females compared to males; other species were specific to one sex but fluctuated depending on experimental conditions. The differences observed suggest that male and female gut tissues and microbiota respond to newly introduced microorganisms differently and that gut-associated microorganisms with host immune system responses and metabolic activity are supported by biology distinct to the host sex. PMID:24814797

Sex and strain dependent differences in mucosal immunology and microbiota composition in mice.

PubMed

Elderman, Marlies; Hugenholtz, Floor; Belzer, Clara; Boekschoten, Mark; van Beek, Adriaan; de Haan, Bart; Savelkoul, Huub; de Vos, Paul; Faas, Marijke

2018-06-18

A dysbiosis in the intestinal microbiome plays a role in the pathogenesis of several immunological diseases. These diseases often show a sex bias, suggesting sex differences in immune responses and in the intestinal microbiome. We hypothesized that sex differences in immune responses are associated with sex differences in microbiota composition. Fecal microbiota composition (MITchip), mRNA expression in intestinal tissue (microarray), and immune cell populations in mesenteric lymph nodes (MLNs) were studied in male and female mice of two mouse strains (C57B1/6OlaHsd and Balb/cOlaHsd). Transcriptomics and microbiota data were combined to identify bacterial species which may potentially be related to sex-specific differences in intestinal immune related genes. We found clear sex differences in intestinal microbiota species, diversity, and richness in healthy mice. However, the nature of the sex effects appeared to be determined by the mouse strain as different bacterial species were enriched in males and females of the two strains. For example, Lactobacillus plantarum and Bacteroides distasonis were enriched in B6 females as compared to B6 males, while Bifidobacterium was enriched BALB/c females as compared to BALB/c males. The strain-dependent sex effects were also observed in the expression of immunological genes in the colon. We found that the abundance of various bacteria (e.g., Clostridium leptum et rel.) which were enriched in B6 females positively correlated with the expression of several genes (e.g., Il-2rb, Ccr3, and Cd80) which could be related to immunological functions, such as inflammatory responses and migration of leukocytes. The abundance of several bacteria (e.g., Faecalibacterium prausnitzii et rel. and Coprobacillus et rel.- Clostridium ramosum et rel.) which were enriched in BALB/c males positively correlated to the expression of several genes (e.g., Apoe, Il-1b, and Stat4) related to several immunological functions, such as proliferation and quantity of lymphocytes. The net result was the same, since both mouse strains showed similar sex induced differences in immune cell populations in the MLNs. Our data suggests a correlation between microbiota and intestinal immune populations in a sex and strain-specific way. These findings may contribute to the development of more sex and genetic specific treatments for intestinal-related disorders.

Sex Differences in the Effects of Unilateral Brain Damage on Intelligence

NASA Astrophysics Data System (ADS)

Inglis, James; Lawson, J. S.

1981-05-01

A sexual dimorphism in the functional asymmetry of the damaged human brain is reflected in a test-specific laterality effect in male but not in female patients. This sex difference explains some contradictions concerning the effects of unilateral brain damage on intelligence in studies in which the influence of sex was overlooked.

Sex-Specific Response Strategies in Mental Rotation

ERIC Educational Resources Information Center

Hirnstein, Marco; Bayer, Ulrike; Hausmann, Markus

2009-01-01

The present study investigated whether the marked sex difference in the original mental rotation test (MRT) is simply a result of sex differences in response strategies. Thirty-four participants (17 males, 17 females) completed the revised Vandenberg and Kuse MRT [Peters, M., Laeng, B., Latham, K., Jackson, M., Zaiyouna, R., & Richardson, C.…

Sex-related differences in stress tolerance in dioecious plants: a critical appraisal in a physiological context.

PubMed

Juvany, Marta; Munné-Bosch, Sergi

2015-10-01

Sex-related differences in reproductive effort can lead to differences in vegetative growth and stress tolerance. However, do all dioecious plants show sex-related differences in stress tolerance? To what extent can the environmental context and modularity mask sex-related differences in stress tolerance? Finally, to what extent can physiological measurements help us understand secondary sexual dimorphism? This opinion paper aims to answer these three basic questions with special emphasis on developments in research in this area over the last decade. Compelling evidence indicates that dimorphic species do not always show differences in stress tolerance between sexes; and when sex-related differences do occur, they seem to be highly species-specific, with greater stress tolerance in females than males in some species, and the opposite in others. The causes of such sex-related species-specific differences are still poorly understood, and more physiological studies and diversity of plant species that allow comparative analyses are needed. Furthermore, studies performed thus far demonstrate that the expression of dioecy can lead to sex-related differences in physiological traits-from leaf gas exchange to gene expression-but the biological significance of modularity and sectoriality governing such differences has been poorly investigated. Future studies that consider the importance of modularity and sectoriality are essential for unravelling the mechanisms underlying stress adaptation in male and female plants growing in their natural habitat. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Sex-Specific Biology of the Human Malaria Parasite Revealed from the Proteomes of Mature Male and Female Gametocytes.

PubMed

Miao, Jun; Chen, Zhao; Wang, Zenglei; Shrestha, Sony; Li, Xiaolian; Li, Runze; Cui, Liwang

2017-04-01

The gametocytes of the malaria parasites are obligate for perpetuating the parasite's life cycle through mosquitoes, but the sex-specific biology of gametocytes is poorly understood. We generated a transgenic line in the human malaria parasite Plasmodium falciparum , which allowed us to accurately separate male and female gametocytes by flow cytometry. In-depth analysis of the proteomes by liquid chromatography-tandem mass spectrometry identified 1244 and 1387 proteins in mature male and female gametocytes, respectively. GFP-tagging of nine selected proteins confirmed their sex-partitions to be agreeable with the results from the proteomic analysis. The sex-specific proteomes showed significant differences that are consistent with the divergent functions of the two sexes. Although the male-specific proteome (119 proteins) is enriched in proteins associated with the flagella and genome replication, the female-specific proteome (262 proteins) is more abundant in proteins involved in metabolism, translation and organellar functions. Compared with the Plasmodium berghei sex-specific proteomes, this study revealed both extensive conservation and considerable divergence between these two species, which reflect the disparities between the two species in proteins involved in cytoskeleton, lipid metabolism and protein degradation. Comparison with three sex-specific proteomes allowed us to obtain high-confidence lists of 73 and 89 core male- and female-specific/biased proteins conserved in Plasmodium The identification of sex-specific/biased proteomes in Plasmodium lays a solid foundation for understanding the molecular mechanisms underlying the unique sex-specific biology in this early-branching eukaryote. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Sex-Specific Biology of the Human Malaria Parasite Revealed from the Proteomes of Mature Male and Female Gametocytes *

PubMed Central

Miao, Jun; Chen, Zhao; Wang, Zenglei; Shrestha, Sony; Li, Xiaolian; Li, Runze; Cui, Liwang

2017-01-01

The gametocytes of the malaria parasites are obligate for perpetuating the parasite's life cycle through mosquitoes, but the sex-specific biology of gametocytes is poorly understood. We generated a transgenic line in the human malaria parasite Plasmodium falciparum, which allowed us to accurately separate male and female gametocytes by flow cytometry. In-depth analysis of the proteomes by liquid chromatography-tandem mass spectrometry identified 1244 and 1387 proteins in mature male and female gametocytes, respectively. GFP-tagging of nine selected proteins confirmed their sex-partitions to be agreeable with the results from the proteomic analysis. The sex-specific proteomes showed significant differences that are consistent with the divergent functions of the two sexes. Although the male-specific proteome (119 proteins) is enriched in proteins associated with the flagella and genome replication, the female-specific proteome (262 proteins) is more abundant in proteins involved in metabolism, translation and organellar functions. Compared with the Plasmodium berghei sex-specific proteomes, this study revealed both extensive conservation and considerable divergence between these two species, which reflect the disparities between the two species in proteins involved in cytoskeleton, lipid metabolism and protein degradation. Comparison with three sex-specific proteomes allowed us to obtain high-confidence lists of 73 and 89 core male- and female-specific/biased proteins conserved in Plasmodium. The identification of sex-specific/biased proteomes in Plasmodium lays a solid foundation for understanding the molecular mechanisms underlying the unique sex-specific biology in this early-branching eukaryote. PMID:28126901

Sexual Aspects of Multilateral Relations

ERIC Educational Resources Information Center

Constantine, Joan M.; Constantine, Larry L.

1971-01-01

This study involved a variety of data gathering techniques focusing on almost every aspect of multilateral marriages. Specific topics covered included sex as motivation, group sex, sleeping arrangements, cohesion, sexual problems, jealousy, roles and sex differences. (Author/CG)

Production and Perception of Sex Differences in Vocalizations of Wied’s Black-Tufted-Ear Marmosets (Callithrix kuhlii)

PubMed Central

Smith, Adam S.; Birnie, Andrew K.; Lane, Kent R.; French, Jeffrey A.

2010-01-01

Males and females from many species produce distinct acoustic variations of functionally identical call types. Social behavior may be primed by sex-specific variation in acoustic features of calls. We present a series of acoustic analyses and playback experiments as methods for investigating this subject. Acoustic parameters of phee calls produced by Wied’s black-tufted-ear marmosets (Callithrix kuhlii) were analyzed for sex differences. Discriminant function analyses showed that calls contained sufficient acoustic variation to predict the sex of the caller. Several frequency variables differed significantly between the sexes. Natural and synthesized calls were presented to male–female pairs. Calls elicited differential behavioral responses based on the sex of the caller. Marmosets became significantly more vigilant following the playback of male phee calls (both natural and synthetic) than following female phee calls. In a second playback experiment, synthesized calls were modified by independently manipulating three parameters that were known to differ between the sexes (low-, peak-, and end-frequency). When end-frequency-modified calls were presented, responsiveness was differentiable by sex of caller but did not differ from responses to natural calls. This suggests that marmosets did not use end-frequency to determine the sex of the caller. Manipulation of peak-and low-frequency parameters eliminated the discrete behavioral responses to male and female calls. Together, these parameters may be important features that encode for the sex-specific signal. Recognition of sex by acoustic cues seems to be a multivariate process that depends on the congruency of acoustic features. PMID:19090554

Sex differences in stress responses: a critical role for corticotropin-releasing factor.

PubMed

Bangasser, Debra A; Wiersielis, Kimberly R

2018-03-01

Rates of post-traumatic stress disorder, panic disorder, and major depression are higher in women than in men. Another shared feature of these disorders is that dysregulation of the stress neuropeptide, corticotropin-releasing factor (CRF), is thought to contribute to their pathophysiology. Therefore, sex differences in responses to CRF could contribute to this sex bias in disease prevalence. Here, we review emerging data from non-human animal models that reveal extensive sex differences in CRF functions ranging from its presynaptic regulation to its postsynaptic efficacy. Specifically, detailed are sex differences in the regulation of CRF-containing neurons and the amount of CRF that they produce. We also describe sex differences in CRF receptor expression, distribution, trafficking, and signaling. Finally, we highlight sex differences in the processes that mitigate the effects of CRF. In most cases, the identified sex differences can lead to increased stress sensitivity in females. Thus, the relevance of these differences for the increased risk of depression and anxiety disorders in women compared to men is also discussed.

Contribution of Knee Flexor and Extensor Strength on Sex-Specific Energy Absorption and Torsional Joint Stiffness During Drop Jumping

PubMed Central

Schmitz, Randy J.; Shultz, Sandra J.

2010-01-01

Abstract Context: Lower extremity injury often occurs during abrupt deceleration when attempting to change the body's direction. Although sex-specific biomechanics have been implicated in the greater risk of acute knee injury in women than in men, it is unknown if sex differences in thigh strength affect sex-specific energy absorption and torsional joint stiffness patterns. Objective: To determine sex differences in energy absorption patterns and joint stiffnesses of the lower extremity during a drop jump and to determine if these sex differences were predicted by knee extensor and flexor strength. Design: Cross-sectional study. Setting: Laboratory environment. Patients or Other Participants: Recreationally active, college-aged students (41 women: age  =  22.1 ± 2.9 years, height  =  1.63 ± 0.07 m, mass  =  59.3 ± 8.0 kg; 40 men: age  =  22.4 ± 2.8 years, height  =  1.77 ± 0.1 m, mass  =  80.9 ± 14.1 kg). Intervention(s): Participants performed knee flexor and extensor maximal voluntary isometric contractions followed by double-leg drop-jump landings. Main Outcome Measure(s): Lower extremity joint energetics (J × N−1 × m−1) and torsional joint stiffnesses (Nm × N−1 × m−1 × degrees−1) were calculated for the hip, knee, and ankle during the initial landing phase. Body weight was measured in newtons and height was measured in meters. Sex comparisons were made and sex-specific regressions determined if thigh muscle strength (Nm/kg) predicted sagittal-plane landing energetics and stiffnesses. Results: Women absorbed 69% more knee energy and had 36% less hip torsional stiffness than men. In women, greater knee extensor strength predicted greater knee energy absorption (R2  =  0.11, P  =  .04), and greater knee flexor strength predicted greater hip torsional stiffness (R2  =  0.12, P  =  .03). Conclusions: Sex-specific biomechanics during the deceleration phase of a drop jump revealed that women used a strategy to attempt to decrease system stiffness. Additionally, only female strength values were predictive of landing energetics and stiffnesses. These findings collectively demonstrated that the task may have been more difficult for women, resulting in a different movement strategy among those with different levels of thigh strength to safely complete the task. Future researchers should look at other predictive factors of observed sex differences. PMID:20831388

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

PubMed Central

Blewett, Lynn A.

2014-01-01

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

How Is Gender Integrated in the Curricula of Dutch Medical Schools? A Quick-Scan on Gender Issues as an Instrument for Change

ERIC Educational Resources Information Center

Verdonk, Petra; Mans, Linda J. L.; Lagro-Janssen, Toine L. M.

2006-01-01

Medical education has not taken on board the growing awareness of sex and gender differences. A nation-wide project to incorporate sex and gender in medical education aims to establish longitudinal gender and sex specific curricula in all Dutch medical schools that move beyond sex and gender differences in reproduction. A baseline assessment was…

A novel application of multi-event modeling to estimate class segregation in a highly migratory oceanic vertebrate.

PubMed

Chapple, T K; Chambert, T; Kanive, P E; Jorgensen, S J; Rotella, J J; Anderson, S D; Carlisle, A B; Block, B A

2016-12-01

Spatial segregation of animals by class (i.e., maturity or sex) within a population due to differential rates of temporary emigration (TE) from study sites can be an important life history feature to consider in population assessment and management. However, such rates are poorly known; new quantitative approaches to address these knowledge gaps are needed. We present a novel application of multi-event models that takes advantage of two sources of detections to differentiate temporary emigration from apparent absence to quantify class segregation within a study population of double-marked (photo-identified and tagged with coded acoustic transmitters) white sharks (Carcharodon carcharias) in central California. We use this model to test if sex-specific patterns in TE result in disparate apparent capture probabilities (p o ) between male and female white sharks, which can affect the observed sex ratio. The best-supported model showed a contrasting pattern of Pr(TE) from coastal aggregation sites between sexes (for males Pr[TE] = 0.015 [95% CI = 0.00, 0.31] and Pr[TE]= 0.57 [0.40, 0.72] for females), but not maturity classes. Additionally, by accounting for Pr(TE) and imperfect detection, we were able to estimate class-specific values of true capture probability (p * ) for tagged and untagged sharks. The best-supported model identified differences between maturity classes but no difference between sexes or tagging impacts (tagged mature sharks p *  = 0.55 (0.46-0.63) and sub-adult sharks p*   = 0.36 (0.25, 0.50); and untagged mature sharks p *  = 0.50 (0.39-0.61) and sub-adults p *  = 0.18 (0.10, 0.31). Estimated sex-based differences in p o were linked to sex-specific differences in Pr(TE) but not in p * ; once the Pr(TE) is accounted for, the p * between sexes was not different. These results indicate that the observed sex ratio is not a consequence of unequal detectability and sex-specific values of Pr(TE) are important drivers of the observed male-dominated sex ratio. Our modeling approach reveals complex class-specific patterns in Pr(TE) and p * in a mark-recapture data set, and highlights challenges for the population modeling and conservation of white sharks in central California. The model we develop here can be used to estimate rates of temporary emigration and class segregation when two detection methods are used. © 2016 by the Ecological Society of America.

Human knee joint anatomy revisited: morphometry in the light of sex-specific total knee arthroplasty.

PubMed

Dargel, Jens; Michael, Joern W P; Feiser, Janna; Ivo, Roland; Koebke, Juergen

2011-04-01

This study investigates differences in the anatomy of male and female knee joints to contribute to the current debate on sex-specific total knee implants. Morphometric data were obtained from 60 human cadaver knees, and sex differences were calculated. All data were corrected for height, and male and female specimens presenting with an identical length of the femur were analyzed as matched pairs. Male linear knee joint dimensions were significantly larger when compared with females. When corrected for differences in height, medial-lateral dimensions of male knees were significantly larger than female; however, matched paired analysis did not prove these differences to be consistent. Although implant design should focus interindividual variations in knee joint anatomy, our data do not support the concept of a female-specific implant design. Copyright © 2011 Elsevier Inc. All rights reserved.

Editorial: Let's talk about sex - the gender binary revisited.

PubMed

Oldehinkel, Albertine J

2017-08-01

Sex refers to biological differences and gender to socioculturally delineated masculine and feminine roles. Sex or gender are included as a covariate or effect modifier in the majority of child psychology and psychiatry studies, and differences found between boys and girls have inspired many researchers to postulate underlying mechanisms. Empirical tests of whether including these proposed explanatory variables actually reduces the variance explained by gender are lagging behind somewhat. That is a pity, because a lot can be gained from a greater focus on the active agents of specific gender differences. As opposed to biological sex as such, some of the processes explaining why a specific outcome shows gender differences may be changeable and so possible prevention targets. Moreover, while the sex binary may be reasonable adequate as a classification variable, the gender binary is far from perfect. Gender is a multidimensional, partly context-dependent factor, and the dichotomy generally used in research does not do justice to the diversity existing within boys and girls. © 2017 Association for Child and Adolescent Mental Health.

Sex Differences in the Effect of Puberty on Hippocampal Morphology

PubMed Central

Satterthwaite, Theodore D.; Vandekar, Simon; Wolf, Daniel H.; Ruparel, Kosha; Roalf, David R.; Jackson, Chad; Elliott, Mark A.; Bilker, Warren B.; Calkins, Monica E.; Prabhakaran, Karthik; Davatzikos, Christos; Hakonarson, Hakon; Gur, Raquel E.; Gur, Ruben C.

2014-01-01

Objective Puberty is the defining process of adolescence, and is accompanied by divergent trajectories of behavior and cognition for males and females. Here we examine whether sex differences exist in the effect of puberty on the morphology of the hippocampus and amygdala. Method T1-weighted structural neuroimaging was performed in a sample of 524 pre- or postpubertal adolescents ages 10–22. Hippocampal and amygdala volume and shape were quantified using FSL’s FIRST procedure and scaled by intracranial volume. The effects on regional volume of age, sex, puberty, and their interactions were examined using linear regression. Postpubertal sex differences were examined using a vertex analysis. Results Prepubertal males and females had similar hippocampal volumes, whereas postpubertal females had significantly larger bilateral hippocampi, resulting in a significant puberty-by-sex interaction even when controlling for age and age-by-sex. This effect was regionally specific and was not apparent in the amygdala. Vertex analysis revealed that postpubertal differences were most prominent in the lateral aspect of the hippocampus bilaterally, corresponding to the CA1 subfield. Conclusions These results establish that there are regionally specific sex differences in the effect of puberty on the hippocampus. These findings are relevant for the understanding of psychiatric disorders that have both hippocampal dysfunction and prominent gender disparities during adolescence. PMID:24565361

Effects of Two Conventional Insecticides on Male-Specific Sex Pheromone Discrimination and Mate Choice in Trichogramma chilonis (Hymenoptera: Trichogrammatidae).

PubMed

Wang, Desen; Lü, Lihua; He, Yurong

2017-04-01

Trichogramma chilonis Ishii is an important natural enemy of many lepidopterous pests on vegetables and field crops. The effects of two conventional insecticides on male-specific sex pheromone discrimination and mate choice in T. chilonis was evaluated in the laboratory. Beta-cypermethrin LC20 exposure induced decreases in male conspecific sex pheromone discrimination and mating rate in T. chilonis, and these decreases were not due to the lower locomotor activity of the surviving T. chilonis males. Spinosad LC20 exposure caused a significant decrease in male locomotor activity of T. chilonis, but did not affect male-specific sex pheromone discrimination (conspecific sex pheromone discrimination or virgin sex pheromone discrimination) or mating rate. However, there was no significant difference in specific sex pheromone discrimination, mate choice, and locomotor activity between control males and males exposed to the low concentration (LC1) of insecticide (beta-cypermethrin or spinosad). In conclusion, beta-cypermethrin LC20 exposure was harmful to male-specific sex pheromone discrimination and mate choice in T. chilonis. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sex Differences in Human and Animal Toxicology.

PubMed

Gochfeld, Michael

2017-01-01

Sex, the states of being female or male, potentially interacts with all xenobiotic exposures, both inadvertent and deliberate, and influences their toxicokinetics (TK), toxicodynamics, and outcomes. Sex differences occur in behavior, exposure, anatomy, physiology, biochemistry, and genetics, accounting for female-male differences in responses to environmental chemicals, diet, and pharmaceuticals, including adverse drug reactions (ADRs). Often viewed as an annoying confounder, researchers have studied only one sex, adjusted for sex, or ignored it. Occupational epidemiology, the basis for understanding many toxic effects in humans, usually excluded women. Likewise, Food and Drug Administration rules excluded women of childbearing age from drug studies for many years. Aside from sex-specific organs, sex differences and sex × age interactions occur for a wide range of disease states as well as hormone-influenced conditions and drug distribution. Women have more ADRs than men; the classic sex hormone paradigm (gonadectomy and replacement) reveals significant interaction of sex and TK including absorption, distribution, metabolisms, and elimination. Studies should be designed to detect sex differences, describe the mechanisms, and interpret these in a broad social, clinical, and evolutionary context with phenomena that do not differ. Sex matters, but how much of a difference is needed to matter remains challenging.

Sex Differences in Human and Animal Toxicology: Toxicokinetics

PubMed Central

Gochfeld, Michael

2016-01-01

Sex, the states of being female or male, potentially interacts with all xenobiotic exposures, both inadvertent and deliberate, and influences their toxicokinetics, toxicodynamics, and outcomes. Sex differences occur in behavior, exposure, anatomy, physiology, biochemistry, and genetics, accounting for female-male differences in responses to environmental chemicals, diet, and pharmaceuticals, including adverse drug reactions. Often viewed as an annoying confounder, researchers have studied only one sex, adjusted for sex, or ignored it. Occupational epidemiology, the basis for understanding many toxic effects in humans, usually excluded women. Likewise FDA rules excluded women of child-bearing age from drug studies for many years. Aside from sex-specific organs, sex differences and sex × age interactions occur for a wide range of disease states as well as hormone-influenced conditions and drug distribution. Women have more adverse drug reactions than men, The Classic Sex Hormone Paradigm (gonadectomy and replacement) reveals significant interaction of sex and toxicokinetics including absorption, distribution, metabolisms and elimination. Studies should be designed to detect sex differences, describe the mechanisms, and interpret these in a broad social, clinical and evolutionary context with phenomena that do not differ. Sex matters, but how much of a difference is needed to matter remains challenging. PMID:27895264

Sex work and the construction of intimacies: meanings and work pragmatics in rural Malawi.

PubMed

Tavory, Iddo; Poulin, Michelle

2012-05-01

This article focuses on Malawian sex workers' understandings of exchange and intimacy, showing how multiple historically emergent categories and specific work pragmatics produce specific patterns of relational meanings. As we show, sex workers make sense of their relationships with clients through two categories. The first is sex work; the second is the chibwenzi , an intimate premarital relational category that emerged from pre-colonial transformations in courtship practices. These categories, in turn, are also shaped differently in different work settings. We use narratives from in-depth interviews with 45 sex workers and bar managers in southern Malawi to describe how the everyday pragmatics of two forms of sex work-performed by "bargirls" and "freelancers"-foster distinct understandings of relationships between them and men they have sex with. Bargirls, who work and live in bars, blurred the boundaries between "regulars" and chibwenzi; freelancers, who are not tethered to a specific work environment, often subverted the meanings of the chibwenzi , presenting these relationships as both intimate and emotionally distant. Through this comparison, we thus refine an approach to the study of the intimacy-exchange nexus, and use it to capture the complexities of gender relations in post-colonial Malawi.

Gender Schema, Gender Constancy, and Sex-Stereotype Knowledge: The Roles of Cognitive Factors in Sex-Stereotype Attributions.

ERIC Educational Resources Information Center

Levy, Gary D.; Carter, D. Bruce

The present study investigated relationships between cognitive components of children's sex-role development and the bases of their attributions of sex-stereotypes to a particular gender. Specifically, it was predicted that the number of sex-stereotypes children correctly attributed would be significantly related to gender differences between the…

Individual diet has sex-dependent effects on vertebrate gut microbiota

PubMed Central

Bolnick, Daniel I.; Snowberg, Lisa K.; Hirsch, Philipp E.; Lauber, Christian L.; Org, Elin; Parks, Brian; Lusis, Aldons J.; Knight, Rob; Caporaso, J. Gregory; Svanbäck, Richard

2014-01-01

Vertebrates harbour diverse communities of symbiotic gut microbes. Host diet is known to alter microbiota composition, implying that dietary treatments might alleviate diseases arising from altered microbial composition (‘dysbiosis’). However, it remains unclear whether diet effects are general or depend on host genotype. Here we show that gut microbiota composition depends on interactions between host diet and sex within populations of wild and laboratory fish, laboratory mice and humans. Within each of two natural fish populations (threespine stickleback and Eurasian perch), among-individual diet variation is correlated with individual differences in gut microbiota. However, these diet–microbiota associations are sex dependent. We document similar sex-specific diet–microbiota correlations in humans. Experimental diet manipulations in laboratory stickleback and mice confirmed that diet affects microbiota differently in males versus females. The prevalence of such genotype by environment (sex by diet) interactions implies that therapies to treat dysbiosis might have sex-specific effects. PMID:25072318

Individual diet has sex-dependent effects on vertebrate gut microbiota.

PubMed

Bolnick, Daniel I; Snowberg, Lisa K; Hirsch, Philipp E; Lauber, Christian L; Org, Elin; Parks, Brian; Lusis, Aldons J; Knight, Rob; Caporaso, J Gregory; Svanbäck, Richard

2014-07-29

Vertebrates harbour diverse communities of symbiotic gut microbes. Host diet is known to alter microbiota composition, implying that dietary treatments might alleviate diseases arising from altered microbial composition ('dysbiosis'). However, it remains unclear whether diet effects are general or depend on host genotype. Here we show that gut microbiota composition depends on interactions between host diet and sex within populations of wild and laboratory fish, laboratory mice and humans. Within each of two natural fish populations (threespine stickleback and Eurasian perch), among-individual diet variation is correlated with individual differences in gut microbiota. However, these diet-microbiota associations are sex dependent. We document similar sex-specific diet-microbiota correlations in humans. Experimental diet manipulations in laboratory stickleback and mice confirmed that diet affects microbiota differently in males versus females. The prevalence of such genotype by environment (sex by diet) interactions implies that therapies to treat dysbiosis might have sex-specific effects.

Sex Differences in Response to Visual Sexual Stimuli: A Review

PubMed Central

Rupp, Heather A.; Wallen, Kim

2009-01-01

This article reviews what is currently known about how men and women respond to the presentation of visual sexual stimuli. While the assumption that men respond more to visual sexual stimuli is generally empirically supported, previous reports of sex differences are confounded by the variable content of the stimuli presented and measurement techniques. We propose that the cognitive processing stage of responding to sexual stimuli is the first stage in which sex differences occur. The divergence between men and women is proposed to occur at this time, reflected in differences in neural activation, and contribute to previously reported sex differences in downstream peripheral physiological responses and subjective reports of sexual arousal. Additionally, this review discusses factors that may contribute to the variability in sex differences observed in response to visual sexual stimuli. Factors include participant variables, such as hormonal state and socialized sexual attitudes, as well as variables specific to the content presented in the stimuli. Based on the literature reviewed, we conclude that content characteristics may differentially produce higher levels of sexual arousal in men and women. Specifically, men appear more influenced by the sex of the actors depicted in the stimuli while women’s response may differ with the context presented. Sexual motivation, perceived gender role expectations, and sexual attitudes are possible influences. These differences are of practical importance to future research on sexual arousal that aims to use experimental stimuli comparably appealing to men and women and also for general understanding of cognitive sex differences. PMID:17668311

Sex differences and hormonal effects on gut microbiota composition in mice.

PubMed

Org, Elin; Mehrabian, Margarete; Parks, Brian W; Shipkova, Petia; Liu, Xiaoqin; Drake, Thomas A; Lusis, Aldons J

2016-07-03

We previously reported quantitation of gut microbiota in a panel of 89 different inbred strains of mice, and we now examine the question of sex differences in microbiota composition. When the total population of 689 mice was examined together, several taxa exhibited significant differences in abundance between sexes but a larger number of differences were observed at the single strain level, suggesting that sex differences can be obscured by host genetics and environmental factors. We also examined a subset of mice on chow and high fat diets and observed sex-by-diet interactions. We further investigated the sex differences using gonadectomized and hormone treated mice from 3 different inbred strains. Principal coordinate analysis with unweighted UniFrac distances revealed very clear effects of gonadectomy and hormone replacement on microbiota composition in all 3 strains. Moreover, bile acid analyses showed gender-specific differences as well as effects of gonodectomy, providing one possible mechanism mediating sex differences in microbiota composition.

Risk of Sex-Specific Cancers in Opposite-Sex and Same-Sex Twins in Denmark and Sweden

PubMed Central

Ahrenfeldt, Linda J.; Skytthe, Axel; Möller, Sören; Czene, Kamila; Adami, Hans-Olov; Mucci, Lorelei A.; Kaprio, Jaakko; Petersen, Inge; Christensen, Kaare; Lindahl-Jacobsen, Rune

2016-01-01

Background Increasing evidence shows that some cancers originate in utero. It is hypothesized that elevated exposure to some steroid hormones might increase cancer risk and that hormone transfer between twin fetuses could result in different prenatal exposure to testosterone. Methods This large-scale prospective twin study compared opposite-sex (OS) and same-sex (SS) twins to test the impact of intrauterine exposures on cancer risk. On the basis of the Danish and Swedish twin and cancer registries, we calculated incidence rate ratios for OS and SS twins, whereas standardized incidence ratios (SIR) with 95% confidence intervals (CI) were calculated for OS/SS twins compared with the general population. Results Atotal of 18,001 cancers were identified during 1943–2009. No significant differences were observed between OS and SS twins, neither for the sex-specific cancers nor for cancer at all sites. All-cause cancer was slightly reduced for OS and SS twins compared with the general population, significant for OS males (SIR, 0.95; 95% CI, 0.92–0.98) and for SS males and females (SIR, 0.97; 95% CI, 0.94–0.99). Conclusions Our data suggest that having a male co-twin—which may entail higher exposure to prenatal testosterone—does not increase the risk of sex-specific cancers in OS females. Furthermore, the study supports that twinning per se is not a risk factor of cancer. Impact Findings are reassuring, as they fail to provide evidence for the hypothesis that endocrine or other difference in the in utero milieu affects the risk of sex-specific cancers. PMID:26282631

Sex-Dependent Effects of Developmental Lead Exposure on the Brain.

PubMed

Singh, Garima; Singh, Vikrant; Sobolewski, Marissa; Cory-Slechta, Deborah A; Schneider, Jay S

2018-01-01

The role of sex as an effect modifier of developmental lead (Pb) exposure has until recently received little attention. Lead exposure in early life can affect brain development with persisting influences on cognitive and behavioral functioning, as well as, elevated risks for developing a variety of diseases and disorders in later life. Although both sexes are affected by Pb exposure, the incidence, manifestation, and severity of outcomes appears to differ in males and females. Results from epidemiologic and animal studies indicate significant effect modification by sex, however, the results are not consistent across studies. Unfortunately, only a limited number of human epidemiological studies have included both sexes in independent outcome analyses limiting our ability to draw definitive conclusions regarding sex-differentiated outcomes. Additionally, due to various methodological differences across studies, there is still not a good mechanistic understanding of the molecular effects of lead on the brain and the factors that influence differential responses to Pb based on sex. In this review, focused on prenatal and postnatal Pb exposures in humans and animal models, we discuss current literature supporting sex differences in outcomes in response to Pb exposure and explore some of the ideas regarding potential molecular mechanisms that may contribute to sex-related differences in outcomes from developmental Pb exposure. The sex-dependent variability in outcomes from developmental Pb exposure may arise from a combination of complex factors, including, but not limited to, intrinsic sex-specific molecular/genetic mechanisms and external risk factors including sex-specific responses to environmental stressors which may act through shared epigenetic pathways to influence the genome and behavioral output.

Sex-Dependent Effects of Developmental Lead Exposure on the Brain

PubMed Central

Singh, Garima; Singh, Vikrant; Sobolewski, Marissa; Cory-Slechta, Deborah A.; Schneider, Jay S.

2018-01-01

The role of sex as an effect modifier of developmental lead (Pb) exposure has until recently received little attention. Lead exposure in early life can affect brain development with persisting influences on cognitive and behavioral functioning, as well as, elevated risks for developing a variety of diseases and disorders in later life. Although both sexes are affected by Pb exposure, the incidence, manifestation, and severity of outcomes appears to differ in males and females. Results from epidemiologic and animal studies indicate significant effect modification by sex, however, the results are not consistent across studies. Unfortunately, only a limited number of human epidemiological studies have included both sexes in independent outcome analyses limiting our ability to draw definitive conclusions regarding sex-differentiated outcomes. Additionally, due to various methodological differences across studies, there is still not a good mechanistic understanding of the molecular effects of lead on the brain and the factors that influence differential responses to Pb based on sex. In this review, focused on prenatal and postnatal Pb exposures in humans and animal models, we discuss current literature supporting sex differences in outcomes in response to Pb exposure and explore some of the ideas regarding potential molecular mechanisms that may contribute to sex-related differences in outcomes from developmental Pb exposure. The sex-dependent variability in outcomes from developmental Pb exposure may arise from a combination of complex factors, including, but not limited to, intrinsic sex-specific molecular/genetic mechanisms and external risk factors including sex-specific responses to environmental stressors which may act through shared epigenetic pathways to influence the genome and behavioral output. PMID:29662502

X chromosome dosage and presence of SRY shape sex-specific differences in DNA methylation at an autosomal region in human cells.

PubMed

Ho, Bianca; Greenlaw, Keelin; Al Tuwaijri, Abeer; Moussette, Sanny; Martínez, Francisco; Giorgio, Elisa; Brusco, Alfredo; Ferrero, Giovanni Battista; Linhares, Natália D; Valadares, Eugênia R; Svartman, Marta; Kalscheuer, Vera M; Rodríguez Criado, Germán; Laprise, Catherine; Greenwood, Celia M T; Naumova, Anna K

2018-02-20

Sexual dimorphism in DNA methylation levels is a recurrent epigenetic feature in different human cell types and has been implicated in predisposition to disease, such as psychiatric and autoimmune disorders. To elucidate the genetic origins of sex-specific DNA methylation, we examined DNA methylation levels in fibroblast cell lines and blood cells from individuals with different combinations of sex chromosome complements and sex phenotypes focusing on a single autosomal region--the differentially methylated region (DMR) in the promoter of the zona pellucida binding protein 2 (ZPBP2) as a reporter. Our data show that the presence of the sex determining region Y (SRY) was associated with lower methylation levels, whereas higher X chromosome dosage in the absence of SRY led to an increase in DNA methylation levels at the ZPBP2 DMR. We mapped the X-linked modifier of DNA methylation to the long arm of chromosome X (Xq13-q21) and tested the impact of mutations in the ATRX and RLIM genes, located in this region, on methylation levels. Neither ATRX nor RLIM mutations influenced ZPBP2 methylation in female carriers. We conclude that sex-specific methylation differences at the autosomal locus result from interaction between a Y-linked factor SRY and at least one X-linked factor that acts in a dose-dependent manner.

Sex steroid signaling: implications for lung diseases.

PubMed

Sathish, Venkatachalem; Martin, Yvette N; Prakash, Y S

2015-06-01

There is increasing recognition that sex hormones (estrogen, progesterone, and testosterone) have biological and pathophysiological actions in peripheral, non-reproductive organs, including the lung. Clinically, sex differences in the incidence, morbidity and mortality of lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, lung cancer and pulmonary hypertension have been noted, although intrinsic sex differences vs. the roles of sex steroids are still not well-understood. Accordingly, it becomes important to ask the following questions: 1) Which sex steroids are involved? 2) How do they affect different components of the lung under normal circumstances? 3) How does sex steroid signaling change in or contribute to lung disease, and in this regard, are sex steroids detrimental or beneficial? As our understanding of sex steroid signaling in the lung improves, it is important to consider whether such information can be used to develop new therapeutic strategies to target lung diseases, perhaps in both sexes or in a sex-specific manner. In this review, we focus on the basics of sex steroid signaling, and the current state of knowledge regarding how they influence structure and function of specific lung components across the life span and in the context of some important lung diseases. We then summarize the potential for sex steroids as useful biomarkers and therapeutic targets in these lung diseases as a basis for future translational research in the area of gender and individualized medicine. Copyright © 2015 Elsevier Inc. All rights reserved.

What was the ancestral sex-determining mechanism in amniote vertebrates?

PubMed

Johnson Pokorná, Martina; Kratochvíl, Lukáš

2016-02-01

Amniote vertebrates, the group consisting of mammals and reptiles including birds, possess various mechanisms of sex determination. Under environmental sex determination (ESD), the sex of individuals depends on the environmental conditions occurring during their development and therefore there are no sexual differences present in their genotypes. Alternatively, through the mode of genotypic sex determination (GSD), sex is determined by a sex-specific genotype, i.e. by the combination of sex chromosomes at various stages of differentiation at conception. As well as influencing sex determination, sex-specific parts of genomes may, and often do, develop specific reproductive or ecological roles in their bearers. Accordingly, an individual with a mismatch between phenotypic (gonadal) and genotypic sex, for example an individual sex-reversed by environmental effects, should have a lower fitness due to the lack of specialized, sex-specific parts of their genome. In this case, evolutionary transitions from GSD to ESD should be less likely than transitions in the opposite direction. This prediction contrasts with the view that GSD was the ancestral sex-determining mechanism for amniote vertebrates. Ancestral GSD would require several transitions from GSD to ESD associated with an independent dedifferentiation of sex chromosomes, at least in the ancestors of crocodiles, turtles, and lepidosaurs (tuataras and squamate reptiles). In this review, we argue that the alternative theory postulating ESD as ancestral in amniotes is more parsimonious and is largely concordant with the theoretical expectations and current knowledge of the phylogenetic distribution and homology of sex-determining mechanisms. © 2014 Cambridge Philosophical Society.

The hypothalamic–pituitary–adrenal axis and sex hormones in chronic stress and obesity: pathophysiological and clinical aspects

PubMed Central

Pasquali, Renato

2012-01-01

Obesity, particularly the abdominal phenotype, has been ascribed to an individual maladaptation to chronic environmental stress exposure mediated by a dysregulation of related neuroendocrine axes. Alterations in the control and action of the hypothalamic–pituitary–adrenal axis play a major role in this context, with the participation of the sympathetic nervous system. The ability to adapt to chronic stress may differ according to sex, with specific pathophysiological events leading to the development of stress-related chronic diseases. This seems to be influenced by the regulatory effects of sex hormones, particularly androgens. Stress may also disrupt the control of feeding, with some differences according to sex. Finally, the amount of experimental data in both animals and humans may help to shed more light on specific phenotypes of obesity, strictly related to the chronic exposure to stress. This challenge may potentially imply a different pathophysiological perspective and, possibly, a specific treatment. PMID:22612409

Sex-specific morphological and physiological differences in the moss Ceratodon purpureus (Dicranales).

PubMed

Slate, Mandy L; Rosenstiel, Todd N; Eppley, Sarah M

2017-11-10

Dioecy and sexual dimorphism occur in many terrestrial plant species but are especially widespread among the bryophytes. Despite the prevalence of dioecy in non-vascular plants, surprisingly little is known about how fine-scale sex-specific cell and leaf morphological traits are correlated with sex-specific physiology and population sex ratios. Such data are critical to understanding the inter-relationship between sex-specific morphological and physiological characters and how their relationship influences population structure. In this study, these data types were assessed to determine how they vary across three populations within one moss species and whether fine-scale morphological traits scale up to physiological and sex ratio characteristics. Twenty cell-, leaf- and canopy-level traits and two photochemical measurements were compared between sexes and populations of the dioecious moss Ceratodon purpureus . Field population-expressed sex ratios were obtained for the same populations. Male and female plants differed in cell, leaf and photochemical measures. These sexual dimorphisms were female biased, with females having larger and thicker leaves and greater values for chlorophyll fluorescence-based, leaf photochemistry measurements than males. Female traits were also more variable than male traits. Interestingly, field population sex ratios were significantly male biased in two study populations and female biased in the third study population. The results demonstrate that the larger morphology and the greater physiological output of female C. purpureus gametophytes compared with males occurs across populations and is likely to have significant effects on resource allocation and biotic interactions. However, this high level of dimorphism does not explain population sex ratio variation in the three study populations tested. This research lays the groundwork for future studies on how differential sex-specific variation in cell and leaf traits influences bryophyte plant fitness. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Recent Sex Chromosome Divergence despite Ancient Dioecy in the Willow Salix viminalis.

PubMed

Pucholt, Pascal; Wright, Alison E; Conze, Lei Liu; Mank, Judith E; Berlin, Sofia

2017-08-01

Sex chromosomes can evolve when recombination is halted between a pair of chromosomes, and this can lead to degeneration of the sex-limited chromosome. In the early stages of differentiation sex chromosomes are homomorphic, and even though homomorphic sex chromosomes are very common throughout animals and plants, we know little about the evolutionary forces shaping these types of sex chromosomes. We used DNA- and RNA-Seq data from females and males to explore the sex chromosomes in the female heterogametic willow, Salix viminalis, a species with ancient dioecy but with homomorphic sex chromosomes. We detected no major sex differences in read coverage in the sex determination (SD) region, indicating that the W region has not significantly degenerated. However, single nucleotide polymorphism densities in the SD region are higher in females compared with males, indicating very recent recombination suppression, followed by the accumulation of sex-specific single nucleotide polymorphisms. Interestingly, we identified two female-specific scaffolds that likely represent W-chromosome-specific sequence. We show that genes located in the SD region display a mild excess of male-biased expression in sex-specific tissue, and we use allele-specific gene expression analysis to show that this is the result of masculinization of expression on the Z chromosome rather than degeneration of female-expression on the W chromosome. Together, our results demonstrate that insertion of small DNA fragments and accumulation of sex-biased gene expression can occur before the detectable decay of the sex-limited chromosome. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

The neural basis of sex differences in sexual behavior: A quantitative meta-analysis

PubMed Central

Poeppl, Timm B.; Langguth, Berthold; Rupprecht, Rainer; Safron, Adam; Bzdok, Danilo; Laird, Angela R.; Eickhoff, Simon B.

2016-01-01

Sexuality as to its etymology presupposes the duality of sexes. Using quantitative neuroimaging meta-analyses, we demonstrate robust sex differences in the neural processing of sexual stimuli in thalamus, hypothalamus, and basal ganglia. In a narrative review, we show how these relate to the well-established sex differences on the behavioral level. More specifically, we describe the neural bases of known poor agreement between self-reported and genital measures of female sexual arousal, of previously proposed male proneness to affective sexual conditioning, as well as hints of unconscious activation of bonding mechanisms during sexual stimulation in women. In summary, our meta-analytic review demonstrates that neurofunctional sex differences during sexual stimulation can account for well-established sex differences in sexual behavior. PMID:27742561

Sex differences in the association between infant markers and later autistic traits.

PubMed

Bedford, Rachael; Jones, Emily J H; Johnson, Mark H; Pickles, Andrew; Charman, Tony; Gliga, Teodora

2016-01-01

Although it is well established that the prevalence of autism spectrum disorder (ASD) is higher in males than females, there is relatively little understanding of the underlying mechanisms and their developmental time course. Sex-specific protective or risk factors have often been invoked to explain these differences, but such factors are yet to be identified. We take a developmental approach, using a prospective sample of 104 infants at high and low familial risk for ASD, to characterise sex differences in infant markers known to predict emerging autism symptoms. We examine three markers previously shown to be associated with later autistic social-communication symptoms: the Autism Observation Scale for Infants (AOSI) total score, attention disengagement speed and gaze following behaviour. Our aim was to test whether sex differences were already present in these markers at 1 year of age, which would suggest sex-specific mechanisms of risk or protection. While no sex differences were found in any of the three markers investigated, we found sex differences in their relationship to 3-year autism traits; all three markers significantly predicted later autism traits only in the boys. Previously identified 'early autism markers' were associated with later autism symptoms only in boys. This suggests that there may be additional moderating risk or protective factors which remain to be identified. Our findings have important implications for prospective studies in terms of directly testing for the moderating effect of sex on emerging autistic traits.

The neural basis of sex differences in sexual behavior: A quantitative meta-analysis.

PubMed

Poeppl, Timm B; Langguth, Berthold; Rupprecht, Rainer; Safron, Adam; Bzdok, Danilo; Laird, Angela R; Eickhoff, Simon B

2016-10-01

Sexuality as to its etymology presupposes the duality of sexes. Using quantitative neuroimaging meta-analyses, we demonstrate robust sex differences in the neural processing of sexual stimuli in thalamus, hypothalamus, and basal ganglia. In a narrative review, we show how these relate to the well-established sex differences on the behavioral level. More specifically, we describe the neural bases of known poor agreement between self-reported and genital measures of female sexual arousal, of previously proposed male proneness to affective sexual conditioning, as well as hints of unconscious activation of bonding mechanisms during sexual stimulation in women. In summary, our meta-analytic review demonstrates that neurofunctional sex differences during sexual stimulation can account for well-established sex differences in sexual behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

Sex moderates the effects of positive and negative affect on clinical pain in patients with knee osteoarthritis.

PubMed

Speed, Traci J; Richards, Jessica M; Finan, Patrick H; Smith, Michael T

2017-07-01

Sex differences in clinical pain severity and response to experimental pain are commonly reported, with women generally showing greater vulnerability. Affect, including state (a single rating) and stable (average daily ratings over two weeks) positive affect and negative affect has also been found to impact pain sensitivity and severity, and research suggests that affect may modulate pain differentially as a function of sex. The current study aimed to examine sex as a moderator of the relationships between affect and pain-related outcomes among participants with knee osteoarthritis (KOA). One hundred and seventy-nine participants (59 men) with KOA completed electronic diaries assessing clinical pain, positive affect, and negative affect. A subset of participants (n=120) underwent quantitative sensory testing, from which a single index of central sensitization to pain was derived. We used multiple regression models to test for the interactive effects of sex and affect (positive versus negative and stable versus state) on pain-related outcomes. We used mixed effects models to test for the moderating effects of sex on the relationships between state affect and pain over time. Sex differences in affect and pain were identified, with men reporting significantly higher stable positive affect and lower central sensitization to pain indexed by quantitative sensory testing, as well as marginally lower KOA-specific clinical pain compared to women. Moreover, there was an interaction between stable positive affect and sex on KOA-specific clinical pain and average daily non-specific pain ratings. Post hoc analyses revealed that men showed trends towards an inverse relationship between stable positive affect and pain outcomes, while women showed no relationship between positive affect and pain. There was also a significant interaction between sex and stable negative affect and sex on KOA-specific pain such that men showed a significantly stronger positive relationship between stable negative affect and KOA-specific pain than women. Sex did not interact with state affect on pain outcomes. Findings suggest that men may be particularly sensitive to the effects of stable positive affect and negative affect on clinical pain. Future work with larger samples is needed in order to identify potential mechanisms driving the sex-specific effects of affect on pain. The current study provides novel data that suggesting that the association of positive affect, negative affect, and pain are different in men versus women with KOA. Further understanding of the difference in affective expression between men and women may lead to the development of novel therapeutic interventions and help to identify additional modifiable factors in the prevention and management of pain. Copyright © 2017 Scandinavian Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Sex differences in health care consumption in Sweden: A register-based cross-sectional study.

PubMed

Osika Friberg, Ingrid; Krantz, Gunilla; Määttä, Sylvia; Järbrink, Krister

2016-05-01

Generally, health care consumption, especially primary care, is greater among women than men. The extent to which this sex difference is explained by reproduction and sex-specific morbidity is unclear. We examined age- and sex-specific health care service utilization and costs in the western region of Sweden. Data were retrieved from a regional health care database of information on total health care consumption in the population. Use of health care resources was divided into the following diagnosis categories: health care associated with reproduction; health care received for sex-specific morbidity; and health care provided for all other conditions. Total per capita cost for health care was 20% higher for women than for men. When adjusted for reproduction and sex-specific morbidity, the cost-difference decreased to 8%. The remaining cost-difference could be explained by women's substantially higher costs for mental and behavioral disorders and diseases of the musculoskeletal system. Women were more likely to receive more accessible, less expensive primary care, while men were more likely to receive specialist inpatient care. The substantially greater use of reproduction-associated care among women, which largely occurs within primary care, might make it easier to also seek health care for other reasons. Efforts to eliminate barriers that prevent men from investing in their health and seeking primary care could reduce future morbidity and costs for specialist care. More studies and appropriate actions are needed to determine why women are overrepresented in mental, behavioral and musculoskeletal disorders. © 2015 the Nordic Societies of Public Health.

Sex-specific mouse liver gene expression: genome-wide analysis of developmental changes from pre-pubertal period to young adulthood

PubMed Central

2012-01-01

Background Early liver development and the transcriptional transitions during hepatogenesis are well characterized. However, gene expression changes during the late postnatal/pre-pubertal to young adulthood period are less well understood, especially with regards to sex-specific gene expression. Methods Microarray analysis of male and female mouse liver was carried out at 3, 4, and 8 wk of age to elucidate developmental changes in gene expression from the late postnatal/pre-pubertal period to young adulthood. Results A large number of sex-biased and sex-independent genes showed significant changes during this developmental period. Notably, sex-independent genes involved in cell cycle, chromosome condensation, and DNA replication were down regulated from 3 wk to 8 wk, while genes associated with metal ion binding, ion transport and kinase activity were up regulated. A majority of genes showing sex differential expression in adult liver did not display sex differences prior to puberty, at which time extensive changes in sex-specific gene expression were seen, primarily in males. Thus, in male liver, 76% of male-specific genes were up regulated and 47% of female-specific genes were down regulated from 3 to 8 wk of age, whereas in female liver 67% of sex-specific genes showed no significant change in expression. In both sexes, genes up regulated from 3 to 8 wk were significantly enriched (p < E-76) in the set of genes positively regulated by the liver transcription factor HNF4α, as determined in a liver-specific HNF4α knockout mouse model, while genes down regulated during this developmental period showed significant enrichment (p < E-65) for negative regulation by HNF4α. Significant enrichment of the developmentally regulated genes in the set of genes subject to positive and negative regulation by pituitary hormone was also observed. Five sex-specific transcriptional regulators showed sex-specific expression at 4 wk (male-specific Ihh; female-specific Cdx4, Cux2, Tox, and Trim24) and may contribute to the developmental changes that lead to global acquisition of liver sex-specificity by 8 wk of age. Conclusions Overall, the observed changes in gene expression during postnatal liver development reflect the deceleration of liver growth and the induction of specialized liver functions, with widespread changes in sex-specific gene expression primarily occurring in male liver. PMID:22475005

Sex-linked inheritance of host-plant specialization in a polyphagous butterfly

PubMed Central

Janz, N.

1998-01-01

I investigated the genetic background of intraspecific variation in oviposition specificity in the generalist butterfly Polygonia c-album. Using reciprocal crosses between two populations that differ in their degree of specialization, I show that specificity is strongly sex-linked. This indicates that genes determining this difference are located primarily on the paternally inherited X-chromosome. The results suggest that intraspecific differences in specificity are caused by the same genetic mechanisms that have been shown to determine interspecific differences in host-plant ranking in other butterflies. Accordingly, the common assumption that specialization and ranking are determined by fundamentally different mechanisms was not supported.

Sex Differences in Moral Reasoning: Response to Walker's (1984) Conclusion That There Are None.

ERIC Educational Resources Information Center

Baumrind, Diana

1986-01-01

Takes issue with Lawrence Walker's literature review on developmental and individual differences in moral reasoning which found no consistent evidence for sex differences in moral development. Argues instead that the source and specific nature of these differences have yet to be established. (HOD)

Variations in body morphology explain sex differences in thermoeffector function during compensable heat stress.

PubMed

Notley, Sean R; Park, Joonhee; Tagami, Kyoko; Ohnishi, Norikazu; Taylor, Nigel A S

2017-05-01

What is the central question of this study? Can sex-related differences in cutaneous vascular and sudomotor responses be explained primarily by variations in the ratio between body surface area and mass during compensable exercise that elicits equivalent heat-loss requirements and mean body temperature changes across participants? What is the main finding and its importance? Mass-specific surface area was a significant determinant of vasomotor and sudomotor responses in men and women, explaining 10-48% of the individual thermoeffector variance. Nonetheless, after accounting for changes in mean body temperature and morphological differences, sex explained only 5% of that inter-individual variability. It was concluded that sex differences in thermoeffector function are morphologically dependent, but not sex dependent. Sex is sometimes thought to be an independent modulator of cutaneous vasomotor and sudomotor function during heat exposure. Nevertheless, it was hypothesized that, when assessed during compensable exercise that evoked equal heat-loss requirements across participants, sex differences in those thermoeffectors would be explained by variations in the ratio between body surface area and mass (specific surface area). To evaluate that possibility, vasomotor and sudomotor functions were assessed in 60 individuals (36 men and 24 women) with widely varying (overlapping) specific surface areas (range, 232.3-292.7 and 241.2-303.1 cm 2  kg -1 , respectively). Subjects completed two trials in compensable conditions (28°C, 36% relative humidity) involving rest (20 min) and steady-state cycling (45 min) at fixed, area-specific metabolic heat-production rates (light, ∼135 W m -2 ; moderate, ∼200 W m -2 ). Equivalent heat-loss requirements and mean body temperature changes were evoked across participants. Forearm blood flow and vascular conductance were positively related to specific surface area during light work in men (r = 0.67 and r = 0.66, respectively; both P < 0.05) and during both exercise intensities in women (light, r = 0.57 and r = 0.69; and moderate, r = 0.64 and r = 0.68; all P < 0.05). Whole-body and local sweat rates were negatively related to that ratio (correlation coefficient range, -0.33 to -0.62; all P < 0.05) during both work rates in men and women. Those relationships accounted for 10-48% of inter-individual thermoeffector variance (P < 0.05). Furthermore, after accounting for morphological differences, sex explained no more than 5% of that variability (P < 0.05). It was concluded that, when assessed during compensable exercise, sex differences in thermoeffector function were largely determined morphologically, rather than being sex dependent. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.

Extremely preterm birth affects boys more and socio-economic and neonatal variables pose sex-specific risks.

PubMed

Månsson, Johanna; Fellman, Vineta; Stjernqvist, Karin

2015-05-01

The early identification of at-risk extremely preterm (EPT) children could improve long-term outcomes. This study sought to investigate sex differences in developmental outcomes and to identify sex-specific predictors at two and a half years of age. We assessed 217 boys and 181 girls born before 27-week gestation using the Bayley Scales of Infant and Toddler Development, third edition (Bayley-III), as a part of the Extremely Preterm Infants in Sweden Study. Sex-specific differences were calculated. Socio-economic, birth and neonatal factors were calculated separately for boys and girls using regression models. Girls scored significantly higher than boys on all Bayley-III indices. In both sexes, brain injury, long-term ventilator treatment and foreign-born mothers predicted lower scores. Receiving breast milk by hospital discharge predicted higher scores. Severe retinopathy of prematurity was the strongest predictor of cognitive and language deficits in boys. High parental education predicted higher cognitive and language scores in girls, whereas severe bronchopulmonary dysplasia was the strongest predictor of motor deficits. Extreme prematurity seems to affect boys more than girls. Socio-economic and neonatal factors confer similar risks or protections on both sexes, but some variables pose sex-specific risks. An awareness of risk factors may provide the basis for treatment and follow-up guidelines. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Sex Differences and Sex Steroids in Lung Health and Disease

PubMed Central

Townsend, Elizabeth A.; Miller, Virginia M.

2012-01-01

Sex differences in the biology of different organ systems and the influence of sex hormones in modulating health and disease are increasingly relevant in clinical and research areas. Although work has focused on sex differences and sex hormones in cardiovascular, musculoskeletal, and neuronal systems, there is now increasing clinical evidence for sex differences in incidence, morbidity, and mortality of lung diseases including allergic diseases (such as asthma), chronic obstructive pulmonary disease, pulmonary fibrosis, lung cancer, as well as pulmonary hypertension. Whether such differences are inherent and/or whether sex steroids play a role in modulating these differences is currently under investigation. The purpose of this review is to define sex differences in lung structure/function under normal and specific disease states, with exploration of whether and how sex hormone signaling mechanisms may explain these clinical observations. Focusing on adult age groups, the review addresses the following: 1) inherent sex differences in lung anatomy and physiology; 2) the importance of certain time points in life such as puberty, pregnancy, menopause, and aging; 3) expression and signaling of sex steroid receptors under normal vs. disease states; 4) potential interplay between different sex steroids; 5) the question of whether sex steroids are beneficial or detrimental to the lung; and 6) the potential use of sex steroid signaling as biomarkers and therapeutic avenues in lung diseases. The importance of focusing on sex differences and sex steroids in the lung lies in the increasing incidence of lung diseases in women and the need to address lung diseases across the life span. PMID:22240244

Acute Stress Modulates Feedback Processing in Men and Women: Differential Effects on the Feedback-Related Negativity and Theta and Beta Power

PubMed Central

Banis, Stella; Geerligs, Linda; Lorist, Monicque M.

2014-01-01

Sex-specific prevalence rates in mental and physical disorders may be partly explained by sex differences in physiological stress responses. Neural networks that might be involved are those underlying feedback processing. Aim of the present EEG study was to investigate whether acute stress alters feedback processing, and whether stress effects differ between men and women. Male and female participants performed a gambling task, in a control and a stress condition. Stress was induced by exposing participants to a noise stressor. Brain activity was analyzed using both event-related potential and time-frequency analyses, measuring the feedback-related negativity (FRN) and feedback-related changes in theta and beta oscillatory power, respectively. While the FRN and feedback-related theta power were similarly affected by stress induction in both sexes, feedback-related beta power depended on the combination of stress induction condition and sex. FRN amplitude and theta power increases were smaller in the stress relative to the control condition in both sexes, demonstrating that acute noise stress impairs performance monitoring irrespective of sex. However, in the stress but not in the control condition, early lower beta-band power increases were larger for men than women, indicating that stress effects on feedback processing are partly sex-dependent. Our findings suggest that sex-specific effects on feedback processing may comprise a factor underlying sex-specific stress responses. PMID:24755943

Poorer right ventricular systolic function and exercise capacity in women after repair of tetralogy of fallot: a sex comparison of standard deviation scores based on sex-specific reference values in healthy control subjects.

PubMed

Sarikouch, Samir; Boethig, Dietmar; Peters, Brigitte; Kropf, Siegfried; Dubowy, Karl-Otto; Lange, Peter; Kuehne, Titus; Haverich, Axel; Beerbaum, Philipp

2013-11-01

In repaired congenital heart disease, there is increasing evidence of sex differences in cardiac remodeling, but there is a lack of comparable data for specific congenital heart defects such as in repaired tetralogy of Fallot. In a prospective multicenter study, a cohort of 272 contemporary patients (158 men; mean age, 14.3±3.3 years [range, 8-20 years]) with repaired tetralogy of Fallot underwent cardiac magnetic resonance for ventricular function and metabolic exercise testing. All data were transformed to standard deviation scores according to the Lambda-Mu-Sigma method by relating individual values to their respective 50th percentile (standard deviation score, 0) in sex-specific healthy control subjects. No sex differences were observed in age at repair, type of repair conducted, or overall hemodynamic results. Relative to sex-specific controls, repaired tetralogy of Fallot in women had larger right ventricular end-systolic volumes (standard deviation scores: women, 4.35; men, 3.25; P=0.001), lower right ventricular ejection fraction (women, -2.83; men, -2.12; P=0.011), lower right ventricular muscle mass (women, 1.58; men 2.45; P=0.001), poorer peak oxygen uptake (women, -1.65; men, -1.14; P<0.001), higher VE/VCO2 (ventilation per unit of carbon dioxide production) slopes (women, 0.88; men 0.58; P=0.012), and reduced peak heart rate (women, -2.16; men -1.74; P=0.017). Left ventricular parameters did not differ between sexes. Relative to their respective sex-specific healthy control subjects, derived standard deviation scores in repaired tetralogy of Fallot suggest that women perform poorer than men in terms of right ventricular systolic function as tested by cardiac magnetic resonance and exercise capacity. This effect cannot be explained by selection bias. Further outcome data are required from longitudinal cohort studies.

Conservation of Sex-Linked Markers among Conspecific Populations of a Viviparous Skink, Niveoscincus ocellatus, Exhibiting Genetic and Temperature-Dependent Sex Determination

PubMed Central

Burridge, Christopher P; Ezaz, Tariq; Wapstra, Erik

2018-01-01

Abstract Sex determination systems are exceptionally diverse and have undergone multiple and independent evolutionary transitions among species, particularly reptiles. However, the mechanisms underlying these transitions have not been established. Here, we tested for differences in sex-linked markers in the only known reptile that is polymorphic for sex determination system, the spotted snow skink, Niveoscincus ocellatus, to quantify the genomic differences that have accompanied this transition. In a highland population, sex is determined genetically, whereas in a lowland population, offspring sex ratio is influenced by temperature. We found a similar number of sex-linked loci in each population, including shared loci, with genotypes consistent with male heterogamety (XY). However, population-specific linkage disequilibrium suggests greater differentiation of sex chromosomes in the highland population. Our results suggest that transitions between sex determination systems can be facilitated by subtle genetic differences. PMID:29659810

Effects of biological sex on the pathophysiology of the heart

PubMed Central

Fazal, Loubina; Azibani, Feriel; Vodovar, Nicolas; Cohen Solal, Alain; Delcayre, Claude; Samuel, Jane-Lise

2014-01-01

Cardiovascular diseases are the leading causes of death in men and women in industrialized countries. While the effects of biological sex on cardiovascular pathophysiology have long been known, the sex-specific mechanisms mediating these processes have been further elucidated over recent years. This review aims at analysing the sex-based differences in cardiac structure and function in adult mammals, and the sex-based differences in the main molecular mechanisms involved in the response of the heart to pathological situations. It emerged from this review that the sex-based difference is a variable that should be dealt with, not only in basic science or clinical research, but also with regards to therapeutic approaches. PMID:23763376

Sex Differences in the Neural Correlates of Specific and General Autobiographical Memory

PubMed Central

Compère, Laurie; Sperduti, Marco; Gallarda, Thierry; Anssens, Adèle; Lion, Stéphanie; Delhommeau, Marion; Martinelli, Pénélope; Devauchelle, Anne-Dominique; Oppenheim, Catherine; Piolino, Pascale

2016-01-01

Autobiographical memory (AM) underlies the formation and temporal continuity over time of personal identity. The few studies on sex-related differences in AM suggest that men and women adopt different cognitive or emotional strategies when retrieving AMs. However, none of the previous works has taken into account the distinction between episodic autobiographical memory (EAM), consisting in the retrieval of specific events by means of mental time travel, and semantic autobiographical memory (SAM), which stores general personal events. Thus, it remains unclear whether differences in these strategies depend on the nature of the memory content to be retrieved. In the present study we employed functional MRI to examine brain activity underlying potential sex differences in EAM and SAM retrieval focusing on the differences in strategies related to the emotional aspects of memories while controlling for basic cognitive strategies. On the behavioral level, there was no significant sex difference in memory performances or subjective feature ratings of either type of AM. Activations common to men and women during AM retrieval were observed in a typical bilateral network comprising medial and lateral temporal regions, precuneus, occipital cortex as well as prefrontal cortex. Contrast analyses revealed that there was no difference between men and women in the EAM condition. In the SAM condition, women showed an increased activity, compared to men, in the dorsal anterior cingulate cortex, inferior parietal and precentral gyrus. Overall, these findings suggest that differential neural activations reflect sex-specific strategies related to emotional aspects of AMs, particularly regarding SAM. We propose that this pattern of activation during SAM retrieval reflects the cognitive cost linked to emotion regulation strategies recruited by women compared to men. These sex-related differences have interesting implications for understanding psychiatric disorders with differential sex prevalence and in which one of key features is overgenerality in AM. PMID:27378884

Space use by Forster's Terns breeding in South San Francisco Bay

USGS Publications Warehouse

Bluso-Demers, J.; Colwell, M.A.; Takekawa, John Y.; Ackerman, Joshua T.

2008-01-01

Parental care behaviors often differ in dimorphic seabirds, leading to sex-specific differences in foraging behaviors. However, few studies have examined sex-specific foraging behaviors in monomorphic seabirds. Using radio-telemetry, we studied Forster's Terns (Sterna forsteri) - a monomorphic and socially monogamous seabird - breeding in the South San Francisco Bay, California. Space use did not differ between males and females. Instead, space use varied by breeding stage and colony affiliation. Forster's Terns were located farthest from the nest during pre-breeding and post-breeding time periods, and closest to the nest during incubation and chick-rearing. Home-range size and core-use areas decreased as the breeding season progressed and were most concentrated in the post-breeding stage. The results of this and other studies indicate that tems, unlike other monomorphic seabirds studied, do not exhibit sex-specific differences in space use.

Sex-specific hip osteoarthritis-associated gait abnormalities: Alterations in dynamic hip abductor function differ in men and women.

PubMed

Foucher, Kharma C

2017-10-01

Hip osteoarthritis results in abnormal gait mechanics, but it is not known whether abnormalities are the same in men and women. The hypothesis tested was that gait abnormalities are different in men and women with hip osteoarthritis vs. sex-specific asymptomatic groups. 150 subjects with mild through severe radiographic hip osteoarthritis and 159 asymptomatic subjects were identified from an Institutional Review Board-approved motion analysis data repository. Sagittal plane hip range of motion and peak external moments about the hip, in all three planes, averaged from normal speed walking trials, were compared for men and women, with and without hip osteoarthritis using analysis of variance. There were significant sex by group interactions for the external peak hip adduction and external rotation moments (P=0.009-0.045). Although asymptomatic women had peak adduction and external rotation moments that were respectively 12% higher and 23% lower than asymptomatic men (P=0.026-0.037), these variables did not differ between men and women with hip osteoarthritis (P≥0.684). The osteoarthritis vs. asymptomatic group difference in the peak hip adduction moment was 45% larger in women than in men. The osteoarthritis vs. asymptomatic group difference in the peak hip external rotation moment was 55% larger for men than for women (P<0.001). Sex did not influence the association between radiographic severity and gait variables. Normal sex differences in gait were not seen in hip osteoarthritis. Sex-specific adaptations may reflect different aspects of hip abductor function. Men and women with hip osteoarthritis may require different interventions to improve function. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Influence of Age and Sex on Genetic Associations with Adult Body Size and Shape: A Large-Scale Genome-Wide Interaction Study.

PubMed

Winkler, Thomas W; Justice, Anne E; Graff, Mariaelisa; Barata, Llilda; Feitosa, Mary F; Chu, Su; Czajkowski, Jacek; Esko, Tõnu; Fall, Tove; Kilpeläinen, Tuomas O; Lu, Yingchang; Mägi, Reedik; Mihailov, Evelin; Pers, Tune H; Rüeger, Sina; Teumer, Alexander; Ehret, Georg B; Ferreira, Teresa; Heard-Costa, Nancy L; Karjalainen, Juha; Lagou, Vasiliki; Mahajan, Anubha; Neinast, Michael D; Prokopenko, Inga; Simino, Jeannette; Teslovich, Tanya M; Jansen, Rick; Westra, Harm-Jan; White, Charles C; Absher, Devin; Ahluwalia, Tarunveer S; Ahmad, Shafqat; Albrecht, Eva; Alves, Alexessander Couto; Bragg-Gresham, Jennifer L; de Craen, Anton J M; Bis, Joshua C; Bonnefond, Amélie; Boucher, Gabrielle; Cadby, Gemma; Cheng, Yu-Ching; Chiang, Charleston W K; Delgado, Graciela; Demirkan, Ayse; Dueker, Nicole; Eklund, Niina; Eiriksdottir, Gudny; Eriksson, Joel; Feenstra, Bjarke; Fischer, Krista; Frau, Francesca; Galesloot, Tessel E; Geller, Frank; Goel, Anuj; Gorski, Mathias; Grammer, Tanja B; Gustafsson, Stefan; Haitjema, Saskia; Hottenga, Jouke-Jan; Huffman, Jennifer E; Jackson, Anne U; Jacobs, Kevin B; Johansson, Åsa; Kaakinen, Marika; Kleber, Marcus E; Lahti, Jari; Mateo Leach, Irene; Lehne, Benjamin; Liu, Youfang; Lo, Ken Sin; Lorentzon, Mattias; Luan, Jian'an; Madden, Pamela A F; Mangino, Massimo; McKnight, Barbara; Medina-Gomez, Carolina; Monda, Keri L; Montasser, May E; Müller, Gabriele; Müller-Nurasyid, Martina; Nolte, Ilja M; Panoutsopoulou, Kalliope; Pascoe, Laura; Paternoster, Lavinia; Rayner, Nigel W; Renström, Frida; Rizzi, Federica; Rose, Lynda M; Ryan, Kathy A; Salo, Perttu; Sanna, Serena; Scharnagl, Hubert; Shi, Jianxin; Smith, Albert Vernon; Southam, Lorraine; Stančáková, Alena; Steinthorsdottir, Valgerdur; Strawbridge, Rona J; Sung, Yun Ju; Tachmazidou, Ioanna; Tanaka, Toshiko; Thorleifsson, Gudmar; Trompet, Stella; Pervjakova, Natalia; Tyrer, Jonathan P; Vandenput, Liesbeth; van der Laan, Sander W; van der Velde, Nathalie; van Setten, Jessica; van Vliet-Ostaptchouk, Jana V; Verweij, Niek; Vlachopoulou, Efthymia; Waite, Lindsay L; Wang, Sophie R; Wang, Zhaoming; Wild, Sarah H; Willenborg, Christina; Wilson, James F; Wong, Andrew; Yang, Jian; Yengo, Loïc; Yerges-Armstrong, Laura M; Yu, Lei; Zhang, Weihua; Zhao, Jing Hua; Andersson, Ehm A; Bakker, Stephan J L; Baldassarre, Damiano; Banasik, Karina; Barcella, Matteo; Barlassina, Cristina; Bellis, Claire; Benaglio, Paola; Blangero, John; Blüher, Matthias; Bonnet, Fabrice; Bonnycastle, Lori L; Boyd, Heather A; Bruinenberg, Marcel; Buchman, Aron S; Campbell, Harry; Chen, Yii-Der Ida; Chines, Peter S; Claudi-Boehm, Simone; Cole, John; Collins, Francis S; de Geus, Eco J C; de Groot, Lisette C P G M; Dimitriou, Maria; Duan, Jubao; Enroth, Stefan; Eury, Elodie; Farmaki, Aliki-Eleni; Forouhi, Nita G; Friedrich, Nele; Gejman, Pablo V; Gigante, Bruna; Glorioso, Nicola; Go, Alan S; Gottesman, Omri; Gräßler, Jürgen; Grallert, Harald; Grarup, Niels; Gu, Yu-Mei; Broer, Linda; Ham, Annelies C; Hansen, Torben; Harris, Tamara B; Hartman, Catharina A; Hassinen, Maija; Hastie, Nicholas; Hattersley, Andrew T; Heath, Andrew C; Henders, Anjali K; Hernandez, Dena; Hillege, Hans; Holmen, Oddgeir; Hovingh, Kees G; Hui, Jennie; Husemoen, Lise L; Hutri-Kähönen, Nina; Hysi, Pirro G; Illig, Thomas; De Jager, Philip L; Jalilzadeh, Shapour; Jørgensen, Torben; Jukema, J Wouter; Juonala, Markus; Kanoni, Stavroula; Karaleftheri, Maria; Khaw, Kay Tee; Kinnunen, Leena; Kittner, Steven J; Koenig, Wolfgang; Kolcic, Ivana; Kovacs, Peter; Krarup, Nikolaj T; Kratzer, Wolfgang; Krüger, Janine; Kuh, Diana; Kumari, Meena; Kyriakou, Theodosios; Langenberg, Claudia; Lannfelt, Lars; Lanzani, Chiara; Lotay, Vaneet; Launer, Lenore J; Leander, Karin; Lindström, Jaana; Linneberg, Allan; Liu, Yan-Ping; Lobbens, Stéphane; Luben, Robert; Lyssenko, Valeriya; Männistö, Satu; Magnusson, Patrik K; McArdle, Wendy L; Menni, Cristina; Merger, Sigrun; Milani, Lili; Montgomery, Grant W; Morris, Andrew P; Narisu, Narisu; Nelis, Mari; Ong, Ken K; Palotie, Aarno; Pérusse, Louis; Pichler, Irene; Pilia, Maria G; Pouta, Anneli; Rheinberger, Myriam; Ribel-Madsen, Rasmus; Richards, Marcus; Rice, Kenneth M; Rice, Treva K; Rivolta, Carlo; Salomaa, Veikko; Sanders, Alan R; Sarzynski, Mark A; Scholtens, Salome; Scott, Robert A; Scott, William R; Sebert, Sylvain; Sengupta, Sebanti; Sennblad, Bengt; Seufferlein, Thomas; Silveira, Angela; Slagboom, P Eline; Smit, Jan H; Sparsø, Thomas H; Stirrups, Kathleen; Stolk, Ronald P; Stringham, Heather M; Swertz, Morris A; Swift, Amy J; Syvänen, Ann-Christine; Tan, Sian-Tsung; Thorand, Barbara; Tönjes, Anke; Tremblay, Angelo; Tsafantakis, Emmanouil; van der Most, Peter J; Völker, Uwe; Vohl, Marie-Claude; Vonk, Judith M; Waldenberger, Melanie; Walker, Ryan W; Wennauer, Roman; Widén, Elisabeth; Willemsen, Gonneke; Wilsgaard, Tom; Wright, Alan F; Zillikens, M Carola; van Dijk, Suzanne C; van Schoor, Natasja M; Asselbergs, Folkert W; de Bakker, Paul I W; Beckmann, Jacques S; Beilby, John; Bennett, David A; Bergman, Richard N; Bergmann, Sven; Böger, Carsten A; Boehm, Bernhard O; Boerwinkle, Eric; Boomsma, Dorret I; Bornstein, Stefan R; Bottinger, Erwin P; Bouchard, Claude; Chambers, John C; Chanock, Stephen J; Chasman, Daniel I; Cucca, Francesco; Cusi, Daniele; Dedoussis, George; Erdmann, Jeanette; Eriksson, Johan G; Evans, Denis A; de Faire, Ulf; Farrall, Martin; Ferrucci, Luigi; Ford, Ian; Franke, Lude; Franks, Paul W; Froguel, Philippe; Gansevoort, Ron T; Gieger, Christian; Grönberg, Henrik; Gudnason, Vilmundur; Gyllensten, Ulf; Hall, Per; Hamsten, Anders; van der Harst, Pim; Hayward, Caroline; Heliövaara, Markku; Hengstenberg, Christian; Hicks, Andrew A; Hingorani, Aroon; Hofman, Albert; Hu, Frank; Huikuri, Heikki V; Hveem, Kristian; James, Alan L; Jordan, Joanne M; Jula, Antti; Kähönen, Mika; Kajantie, Eero; Kathiresan, Sekar; Kiemeney, Lambertus A L M; Kivimaki, Mika; Knekt, Paul B; Koistinen, Heikki A; Kooner, Jaspal S; Koskinen, Seppo; Kuusisto, Johanna; Maerz, Winfried; Martin, Nicholas G; Laakso, Markku; Lakka, Timo A; Lehtimäki, Terho; Lettre, Guillaume; Levinson, Douglas F; Lind, Lars; Lokki, Marja-Liisa; Mäntyselkä, Pekka; Melbye, Mads; Metspalu, Andres; Mitchell, Braxton D; Moll, Frans L; Murray, Jeffrey C; Musk, Arthur W; Nieminen, Markku S; Njølstad, Inger; Ohlsson, Claes; Oldehinkel, Albertine J; Oostra, Ben A; Palmer, Lyle J; Pankow, James S; Pasterkamp, Gerard; Pedersen, Nancy L; Pedersen, Oluf; Penninx, Brenda W; Perola, Markus; Peters, Annette; Polašek, Ozren; Pramstaller, Peter P; Psaty, Bruce M; Qi, Lu; Quertermous, Thomas; Raitakari, Olli T; Rankinen, Tuomo; Rauramaa, Rainer; Ridker, Paul M; Rioux, John D; Rivadeneira, Fernando; Rotter, Jerome I; Rudan, Igor; den Ruijter, Hester M; Saltevo, Juha; Sattar, Naveed; Schunkert, Heribert; Schwarz, Peter E H; Shuldiner, Alan R; Sinisalo, Juha; Snieder, Harold; Sørensen, Thorkild I A; Spector, Tim D; Staessen, Jan A; Stefania, Bandinelli; Thorsteinsdottir, Unnur; Stumvoll, Michael; Tardif, Jean-Claude; Tremoli, Elena; Tuomilehto, Jaakko; Uitterlinden, André G; Uusitupa, Matti; Verbeek, André L M; Vermeulen, Sita H; Viikari, Jorma S; Vitart, Veronique; Völzke, Henry; Vollenweider, Peter; Waeber, Gérard; Walker, Mark; Wallaschofski, Henri; Wareham, Nicholas J; Watkins, Hugh; Zeggini, Eleftheria; Chakravarti, Aravinda; Clegg, Deborah J; Cupples, L Adrienne; Gordon-Larsen, Penny; Jaquish, Cashell E; Rao, D C; Abecasis, Goncalo R; Assimes, Themistocles L; Barroso, Inês; Berndt, Sonja I; Boehnke, Michael; Deloukas, Panos; Fox, Caroline S; Groop, Leif C; Hunter, David J; Ingelsson, Erik; Kaplan, Robert C; McCarthy, Mark I; Mohlke, Karen L; O'Connell, Jeffrey R; Schlessinger, David; Strachan, David P; Stefansson, Kari; van Duijn, Cornelia M; Hirschhorn, Joel N; Lindgren, Cecilia M; Heid, Iris M; North, Kari E; Borecki, Ingrid B; Kutalik, Zoltán; Loos, Ruth J F

2015-10-01

Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially between men and women. To systematically screen for age- and/or sex-specific effects of genetic variants on BMI and WHRadjBMI, we performed meta-analyses of 114 studies (up to 320,485 individuals of European descent) with genome-wide chip and/or Metabochip data by the Genetic Investigation of Anthropometric Traits (GIANT) Consortium. Each study tested the association of up to ~2.8M SNPs with BMI and WHRadjBMI in four strata (men ≤50y, men >50y, women ≤50y, women >50y) and summary statistics were combined in stratum-specific meta-analyses. We then screened for variants that showed age-specific effects (G x AGE), sex-specific effects (G x SEX) or age-specific effects that differed between men and women (G x AGE x SEX). For BMI, we identified 15 loci (11 previously established for main effects, four novel) that showed significant (FDR<5%) age-specific effects, of which 11 had larger effects in younger (<50y) than in older adults (≥50y). No sex-dependent effects were identified for BMI. For WHRadjBMI, we identified 44 loci (27 previously established for main effects, 17 novel) with sex-specific effects, of which 28 showed larger effects in women than in men, five showed larger effects in men than in women, and 11 showed opposite effects between sexes. No age-dependent effects were identified for WHRadjBMI. This is the first genome-wide interaction meta-analysis to report convincing evidence of age-dependent genetic effects on BMI. In addition, we confirm the sex-specificity of genetic effects on WHRadjBMI. These results may provide further insights into the biology that underlies weight change with age or the sexually dimorphism of body shape.

The Influence of Age and Sex on Genetic Associations with Adult Body Size and Shape: A Large-Scale Genome-Wide Interaction Study

PubMed Central

Feitosa, Mary F.; Chu, Su; Czajkowski, Jacek; Esko, Tõnu; Fall, Tove; Kilpeläinen, Tuomas O.; Lu, Yingchang; Mägi, Reedik; Mihailov, Evelin; Pers, Tune H.; Rüeger, Sina; Teumer, Alexander; Ehret, Georg B.; Ferreira, Teresa; Heard-Costa, Nancy L.; Karjalainen, Juha; Lagou, Vasiliki; Mahajan, Anubha; Neinast, Michael D.; Prokopenko, Inga; Simino, Jeannette; Teslovich, Tanya M.; Jansen, Rick; Westra, Harm-Jan; White, Charles C.; Absher, Devin; Ahluwalia, Tarunveer S.; Ahmad, Shafqat; Albrecht, Eva; Alves, Alexessander Couto; Bragg-Gresham, Jennifer L.; de Craen, Anton J. M.; Bis, Joshua C.; Bonnefond, Amélie; Boucher, Gabrielle; Cadby, Gemma; Cheng, Yu-Ching; Chiang, Charleston W. K.; Delgado, Graciela; Demirkan, Ayse; Dueker, Nicole; Eklund, Niina; Eiriksdottir, Gudny; Eriksson, Joel; Feenstra, Bjarke; Fischer, Krista; Frau, Francesca; Galesloot, Tessel E.; Geller, Frank; Goel, Anuj; Gorski, Mathias; Grammer, Tanja B.; Gustafsson, Stefan; Haitjema, Saskia; Hottenga, Jouke-Jan; Huffman, Jennifer E.; Jackson, Anne U.; Jacobs, Kevin B.; Johansson, Åsa; Kaakinen, Marika; Kleber, Marcus E.; Lahti, Jari; Leach, Irene Mateo; Lehne, Benjamin; Liu, Youfang; Lo, Ken Sin; Lorentzon, Mattias; Luan, Jian'an; Madden, Pamela A. F.; Mangino, Massimo; McKnight, Barbara; Medina-Gomez, Carolina; Monda, Keri L.; Montasser, May E.; Müller, Gabriele; Müller-Nurasyid, Martina; Nolte, Ilja M.; Panoutsopoulou, Kalliope; Pascoe, Laura; Paternoster, Lavinia; Rayner, Nigel W.; Renström, Frida; Rizzi, Federica; Rose, Lynda M.; Ryan, Kathy A.; Salo, Perttu; Sanna, Serena; Scharnagl, Hubert; Shi, Jianxin; Smith, Albert Vernon; Southam, Lorraine; Stančáková, Alena; Steinthorsdottir, Valgerdur; Strawbridge, Rona J.; Sung, Yun Ju; Tachmazidou, Ioanna; Tanaka, Toshiko; Thorleifsson, Gudmar; Trompet, Stella; Pervjakova, Natalia; Tyrer, Jonathan P.; Vandenput, Liesbeth; van der Laan, Sander W; van der Velde, Nathalie; van Setten, Jessica; van Vliet-Ostaptchouk, Jana V.; Verweij, Niek; Vlachopoulou, Efthymia; Waite, Lindsay L.; Wang, Sophie R.; Wang, Zhaoming; Wild, Sarah H.; Willenborg, Christina; Wilson, James F.; Wong, Andrew; Yang, Jian; Yengo, Loïc; Yerges-Armstrong, Laura M.; Yu, Lei; Zhang, Weihua; Zhao, Jing Hua; Andersson, Ehm A.; Bakker, Stephan J. L.; Baldassarre, Damiano; Banasik, Karina; Barcella, Matteo; Barlassina, Cristina; Bellis, Claire; Benaglio, Paola; Blangero, John; Blüher, Matthias; Bonnet, Fabrice; Bonnycastle, Lori L.; Boyd, Heather A.; Bruinenberg, Marcel; Buchman, Aron S; Campbell, Harry; Chen, Yii-Der Ida; Chines, Peter S.; Claudi-Boehm, Simone; Cole, John; Collins, Francis S.; de Geus, Eco J. C.; de Groot, Lisette C. P. G. M.; Dimitriou, Maria; Duan, Jubao; Enroth, Stefan; Eury, Elodie; Farmaki, Aliki-Eleni; Forouhi, Nita G.; Friedrich, Nele; Gejman, Pablo V.; Gigante, Bruna; Glorioso, Nicola; Go, Alan S.; Gottesman, Omri; Gräßler, Jürgen; Grallert, Harald; Grarup, Niels; Gu, Yu-Mei; Broer, Linda; Ham, Annelies C.; Hansen, Torben; Harris, Tamara B.; Hartman, Catharina A.; Hassinen, Maija; Hastie, Nicholas; Hattersley, Andrew T.; Heath, Andrew C.; Henders, Anjali K.; Hernandez, Dena; Hillege, Hans; Holmen, Oddgeir; Hovingh, Kees G; Hui, Jennie; Husemoen, Lise L.; Hutri-Kähönen, Nina; Hysi, Pirro G.; Illig, Thomas; De Jager, Philip L.; Jalilzadeh, Shapour; Jørgensen, Torben; Jukema, J. Wouter; Juonala, Markus; Kanoni, Stavroula; Karaleftheri, Maria; Khaw, Kay Tee; Kinnunen, Leena; Kittner, Steven J.; Koenig, Wolfgang; Kolcic, Ivana; Kovacs, Peter; Krarup, Nikolaj T.; Kratzer, Wolfgang; Krüger, Janine; Kuh, Diana; Kumari, Meena; Kyriakou, Theodosios; Langenberg, Claudia; Lannfelt, Lars; Lanzani, Chiara; Lotay, Vaneet; Launer, Lenore J.; Leander, Karin; Lindström, Jaana; Linneberg, Allan; Liu, Yan-Ping; Lobbens, Stéphane; Luben, Robert; Lyssenko, Valeriya; Männistö, Satu; Magnusson, Patrik K.; McArdle, Wendy L.; Menni, Cristina; Merger, Sigrun; Milani, Lili; Montgomery, Grant W.; Morris, Andrew P.; Narisu, Narisu; Nelis, Mari; Ong, Ken K.; Palotie, Aarno; Pérusse, Louis; Pichler, Irene; Pilia, Maria G.; Pouta, Anneli; Rheinberger, Myriam; Ribel-Madsen, Rasmus; Richards, Marcus; Rice, Kenneth M.; Rice, Treva K.; Rivolta, Carlo; Salomaa, Veikko; Sanders, Alan R.; Sarzynski, Mark A.; Scholtens, Salome; Scott, Robert A.; Scott, William R.; Sebert, Sylvain; Sengupta, Sebanti; Sennblad, Bengt; Seufferlein, Thomas; Silveira, Angela; Slagboom, P. Eline; Smit, Jan H.; Sparsø, Thomas H.; Stirrups, Kathleen; Stolk, Ronald P.; Stringham, Heather M.; Swertz, Morris A; Swift, Amy J.; Syvänen, Ann-Christine; Tan, Sian-Tsung; Thorand, Barbara; Tönjes, Anke; Tremblay, Angelo; Tsafantakis, Emmanouil; van der Most, Peter J.; Völker, Uwe; Vohl, Marie-Claude; Vonk, Judith M.; Waldenberger, Melanie; Walker, Ryan W.; Wennauer, Roman; Widén, Elisabeth; Willemsen, Gonneke; Wilsgaard, Tom; Wright, Alan F.; Zillikens, M. Carola; van Dijk, Suzanne C.; van Schoor, Natasja M.; Asselbergs, Folkert W.; de Bakker, Paul I. W.; Beckmann, Jacques S.; Beilby, John; Bennett, David A.; Bergman, Richard N.; Bergmann, Sven; Böger, Carsten A.; Boehm, Bernhard O.; Boerwinkle, Eric; Boomsma, Dorret I.; Bornstein, Stefan R.; Bottinger, Erwin P.; Bouchard, Claude; Chambers, John C.; Chanock, Stephen J.; Chasman, Daniel I.; Cucca, Francesco; Cusi, Daniele; Dedoussis, George; Erdmann, Jeanette; Eriksson, Johan G.; Evans, Denis A.; de Faire, Ulf; Farrall, Martin; Ferrucci, Luigi; Ford, Ian; Franke, Lude; Franks, Paul W.; Froguel, Philippe; Gansevoort, Ron T.; Gieger, Christian; Grönberg, Henrik; Gudnason, Vilmundur; Gyllensten, Ulf; Hall, Per; Hamsten, Anders; van der Harst, Pim; Hayward, Caroline; Heliövaara, Markku; Hengstenberg, Christian; Hicks, Andrew A; Hingorani, Aroon; Hofman, Albert; Hu, Frank; Huikuri, Heikki V.; Hveem, Kristian; James, Alan L.; Jordan, Joanne M.; Jula, Antti; Kähönen, Mika; Kajantie, Eero; Kathiresan, Sekar; Kiemeney, Lambertus A. L. M.; Kivimaki, Mika; Knekt, Paul B.; Koistinen, Heikki A.; Kooner, Jaspal S.; Koskinen, Seppo; Kuusisto, Johanna; Maerz, Winfried; Martin, Nicholas G; Laakso, Markku; Lakka, Timo A.; Lehtimäki, Terho; Lettre, Guillaume; Levinson, Douglas F.; Lind, Lars; Lokki, Marja-Liisa; Mäntyselkä, Pekka; Melbye, Mads; Metspalu, Andres; Mitchell, Braxton D.; Moll, Frans L.; Murray, Jeffrey C.; Musk, Arthur W.; Nieminen, Markku S.; Njølstad, Inger; Ohlsson, Claes; Oldehinkel, Albertine J.; Oostra, Ben A.; Palmer, Lyle J; Pankow, James S.; Pasterkamp, Gerard; Pedersen, Nancy L.; Pedersen, Oluf; Penninx, Brenda W.; Perola, Markus; Peters, Annette; Polašek, Ozren; Pramstaller, Peter P.; Psaty, Bruce M.; Qi, Lu; Quertermous, Thomas; Raitakari, Olli T.; Rankinen, Tuomo; Rauramaa, Rainer; Ridker, Paul M.; Rioux, John D.; Rivadeneira, Fernando; Rotter, Jerome I.; Rudan, Igor; den Ruijter, Hester M.; Saltevo, Juha; Sattar, Naveed; Schunkert, Heribert; Schwarz, Peter E. H.; Shuldiner, Alan R.; Sinisalo, Juha; Snieder, Harold; Sørensen, Thorkild I. A.; Spector, Tim D.; Staessen, Jan A.; Stefania, Bandinelli; Thorsteinsdottir, Unnur; Stumvoll, Michael; Tardif, Jean-Claude; Tremoli, Elena; Tuomilehto, Jaakko; Uitterlinden, André G.; Uusitupa, Matti; Verbeek, André L. M.; Vermeulen, Sita H.; Viikari, Jorma S.; Vitart, Veronique; Völzke, Henry; Vollenweider, Peter; Waeber, Gérard; Walker, Mark; Wallaschofski, Henri; Wareham, Nicholas J.; Watkins, Hugh; Zeggini, Eleftheria; Chakravarti, Aravinda; Clegg, Deborah J.; Cupples, L. Adrienne; Gordon-Larsen, Penny; Jaquish, Cashell E.; Rao, D. C.; Abecasis, Goncalo R.; Assimes, Themistocles L.; Barroso, Inês; Berndt, Sonja I.; Boehnke, Michael; Deloukas, Panos; Fox, Caroline S.; Groop, Leif C.; Hunter, David J.; Ingelsson, Erik; Kaplan, Robert C.; McCarthy, Mark I.; Mohlke, Karen L.; O'Connell, Jeffrey R.; Schlessinger, David; Strachan, David P.; Stefansson, Kari; van Duijn, Cornelia M.; Hirschhorn, Joel N.; Lindgren, Cecilia M.; Heid, Iris M.; North, Kari E.; Borecki, Ingrid B.; Kutalik, Zoltán; Loos, Ruth J. F.

2015-01-01

Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially between men and women. To systematically screen for age- and/or sex-specific effects of genetic variants on BMI and WHRadjBMI, we performed meta-analyses of 114 studies (up to 320,485 individuals of European descent) with genome-wide chip and/or Metabochip data by the Genetic Investigation of Anthropometric Traits (GIANT) Consortium. Each study tested the association of up to ~2.8M SNPs with BMI and WHRadjBMI in four strata (men ≤50y, men >50y, women ≤50y, women >50y) and summary statistics were combined in stratum-specific meta-analyses. We then screened for variants that showed age-specific effects (G x AGE), sex-specific effects (G x SEX) or age-specific effects that differed between men and women (G x AGE x SEX). For BMI, we identified 15 loci (11 previously established for main effects, four novel) that showed significant (FDR<5%) age-specific effects, of which 11 had larger effects in younger (<50y) than in older adults (≥50y). No sex-dependent effects were identified for BMI. For WHRadjBMI, we identified 44 loci (27 previously established for main effects, 17 novel) with sex-specific effects, of which 28 showed larger effects in women than in men, five showed larger effects in men than in women, and 11 showed opposite effects between sexes. No age-dependent effects were identified for WHRadjBMI. This is the first genome-wide interaction meta-analysis to report convincing evidence of age-dependent genetic effects on BMI. In addition, we confirm the sex-specificity of genetic effects on WHRadjBMI. These results may provide further insights into the biology that underlies weight change with age or the sexually dimorphism of body shape. PMID:26426971

Assessment of sex specific endocrine disrupting effects in the prenatal and pre-pubertal rodent brain.

PubMed

Rebuli, Meghan E; Patisaul, Heather B

2016-06-01

Brain sex differences are found in nearly every region of the brain and fundamental to sexually dimorphic behaviors as well as disorders of the brain and behavior. These differences are organized during gestation and early adolescence and detectable prior to puberty. Endocrine disrupting compounds (EDCs) interfere with hormone action and are thus prenatal exposure is hypothesized to disrupt the formation of sex differences, and contribute to the increased prevalence of pediatric neuropsychiatric disorders that present with a sex bias. Available evidence for the ability of EDCs to impact the emergence of brain sex differences in the rodent brain was reviewed here, with a focus on effects detected at or before puberty. The peer-reviewed literature was searched using PubMed, and all relevant papers published by January 31, 2015 were incorporated. Endpoints of interest included molecular cellular and neuroanatomical effects. Studies on behavioral endpoints were not included because numerous reviews of that literature are available. The hypothalamus was found to be particularly affected by estrogenic EDCs in a sex, time, and exposure dependent manner. The hippocampus also appears vulnerable to endocrine disruption by BPA and PCBs although there is little evidence from the pre-pubertal literature to make any conclusions about sex-specific effects. Gestational EDC exposure can alter fetal neurogenesis and gene expression throughout the brain including the cortex and cerebellum. The available literature primarily focuses on a few, well characterized EDCs, but little data is available for emerging contaminants. The developmental EDC exposure literature demonstrates evidence of altered neurodevelopment as early as fetal life, with sex specific effects observed throughout the brain even before puberty. Copyright © 2015 Elsevier Ltd. All rights reserved.

Gestational dietary protein is associated with sex specific decrease in blood flow, fetal heart growth and post-natal blood pressure of progeny.

PubMed

Hernandez-Medrano, Juan H; Copping, Katrina J; Hoare, Andrew; Wapanaar, Wendela; Grivell, Rosalie; Kuchel, Tim; Miguel-Pacheco, Giuliana; McMillen, I Caroline; Rodgers, Raymond J; Perry, Viv E A

2015-01-01

The incidence of adverse pregnancy outcomes is higher in pregnancies where the fetus is male. Sex specific differences in feto-placental perfusion indices identified by Doppler assessment have recently been associated with placental insufficiency and fetal growth restriction. This study aims to investigate sex specific differences in placental perfusion and to correlate these changes with fetal growth. It represents the largest comprehensive study under field conditions of uterine hemodynamics in a monotocous species, with a similar long gestation period to the human. Primiparous 14 mo heifers in Australia (n=360) and UK (n=180) were either individually or group fed, respectively, diets with differing protein content (18, 14, 10 or 7% crude protein (CP)) from 60 d prior to 98 days post conception (dpc). Fetuses and placentae were excised at 98 dpc (n = 48). Fetal development an median uterine artery blood flow were assessed monthly from 36 dpc until term using B-mode and Doppler ultrasonography. MUA blood flow to the male feto-placental unit increased in early pregnancy associated with increased fetal growth. Protein restriction before and shortly after conception (-60 d up to 23 dpc) increased MUA diameter and indices of velocity during late pregnancy, reduced fetal heart weight in the female fetus and increased heart rate at birth, but decreased systolic blood pressure at six months of age. Sex specific differences both in feto-placental Doppler perfusion indices and response of these indices to dietary perturbations were observed. Further, maternal diet affected development of fetal cardiovascular system associated with altered fetal haemodynamics in utero, with such effects having a sex bias. The results from this study provide further insight into the gender specific circulatory differences present in the fetal period and developing cardiovascular system.

Biological Sex Differences in Depression: A Systematic Review.

PubMed

Labaka, Ainitze; Goñi-Balentziaga, Olatz; Lebeña, Andrea; Pérez-Tejada, Joana

2018-07-01

Depression is the leading cause of disability worldwide, and its prevalence is 2 times higher in women than in men. There is, however, a lack of data on sex-specific pathophysiology of this disorder. The purpose of this systematic review is to identify the biological sex differences found in major depressive disorder (MDD) in studies published in the last 10 years. We conducted a literature search using the Medline, PsycInfo, PubMed, and Web of Science databases, selecting English-language studies that included physiological measures compared by sex in addition to MDD. We identified 20 relevant studies, which consisted primarily of mixed methodology and samples. The reported physiological measures comprised a variety of serum biomarkers, gene mRNA expression, and brain activity. Findings suggest different biological patterns in those with MDD depending on sex. Specifically, women presented higher levels of inflammatory, neurotrophic, and serotonergic markers and a stronger correlation between levels of some inflammatory and neurotrophic factors and the severity of symptoms. This review provides information about possible different biological patterns for women and men with depressive disorder and may have important implications for treatment. Future research should include homogeneous samples; make comparisons based on sex, control sex hormone fluctuations and pharmacological treatment; and use consistent criteria for evaluating psychobiological changes in MDD.

Sex-specific habitat suitability models for Panthera tigris in Chitwan National Park, Nepal

NASA Astrophysics Data System (ADS)

Battle, Curtis Scott

Although research on wildlife species across taxa has shown that males and females differentially select habitat, sex-specific models of habitat suitability for endangered species are uncommon. Here, we developed such models for Bengal Tigers (Panthera tigris) based on camera trap data collected from 20 January to 22 March, 2010, within Chitwan National Park, Nepal, and its buffer zone. We compared these to a sex-indiscriminate habitat suitability model in order to identify information that is lost when occurrence data for both sexes are included in the same model, as well as to assess the benefits of a sex-specific approach to habitat suitability modelling. Our sex-specific models allowed us to produce more informative and detailed habitat suitability maps, highlighting key differences in the distribution of suitable habitats for males and females, preferences in vegetation structure, and habitat use near human settlements. In the context of global tiger conservation, such information is essential to fulfilling established conservation goals and population recovery targets.

The origin and evolution of vertebrate sex chromosomes and dosage compensation

PubMed Central

Livernois, A M; Graves, J A M; Waters, P D

2012-01-01

In mammals, birds, snakes and many lizards and fish, sex is determined genetically (either male XY heterogamy or female ZW heterogamy), whereas in alligators, and in many reptiles and turtles, the temperature at which eggs are incubated determines sex. Evidently, different sex-determining systems (and sex chromosome pairs) have evolved independently in different vertebrate lineages. Homology shared by Xs and Ys (and Zs and Ws) within species demonstrates that differentiated sex chromosomes were once homologous, and that the sex-specific non-recombining Y (or W) was progressively degraded. Consequently, genes are left in single copy in the heterogametic sex, which results in an imbalance of the dosage of genes on the sex chromosomes between the sexes, and also relative to the autosomes. Dosage compensation has evolved in diverse species to compensate for these dose differences, with the stringency of compensation apparently differing greatly between lineages, perhaps reflecting the concentration of genes on the original autosome pair that required dosage compensation. We discuss the organization and evolution of amniote sex chromosomes, and hypothesize that dosage insensitivity might predispose an autosome to evolving function as a sex chromosome. PMID:22086077

Parent-Endorsed Sex Differences in Toddlers with and without ASD: Utilizing the M-CHAT

ERIC Educational Resources Information Center

Øien, Roald A.; Hart, Logan; Schjølberg, Synnve; Wall, Carla A.; Kim, Elizabeth S.; Nordahl-Hansen, Anders; Eisemann, Martin R.; Chawarska, Katarzyna; Volkmar, Fred R.; Shic, Frederick

2017-01-01

Sex differences in typical development can provide context for understanding ASD. Baron-Cohen ("Trends Cogn Sci" 6(6):248-254, 2002) suggested ASD could be considered an extreme expression of normal male, compared to female, phenotypic profiles. In this paper, sex-specific M-CHAT scores from N = 53,728 18-month-old toddlers, including n…

Sex-related alterations of gut microbiota composition in the BTBR mouse model of autism spectrum disorder.

PubMed

Coretti, Lorena; Cristiano, Claudia; Florio, Ermanno; Scala, Giovanni; Lama, Adriano; Keller, Simona; Cuomo, Mariella; Russo, Roberto; Pero, Raffaela; Paciello, Orlando; Mattace Raso, Giuseppina; Meli, Rosaria; Cocozza, Sergio; Calignano, Antonio; Chiariotti, Lorenzo; Lembo, Francesca

2017-03-28

Alterations of microbiota-gut-brain axis have been invoked in the pathogenesis of autism spectrum disorders (ASD). Mouse models could represent an excellent tool to understand how gut dysbiosis and related alterations may contribute to autistic phenotype. In this study we paralleled gut microbiota (GM) profiles, behavioral characteristics, intestinal integrity and immunological features of colon tissues in BTBR T + tf/J (BTBR) inbred mice, a well established animal model of ASD. Sex differences, up to date poorly investigated in animal models, were specifically addressed. Results showed that BTBR mice of both sexes presented a marked intestinal dysbiosis, alterations of behavior, gut permeability and immunological state with respect to prosocial C57BL/6j (C57) strain. Noticeably, sex-related differences were clearly detected. We identified Bacteroides, Parabacteroides, Sutterella, Dehalobacterium and Oscillospira genera as key drivers of sex-specific gut microbiota profiles associated with selected pathological traits. Taken together, our findings indicate that alteration of GM in BTBR mice shows relevant sex-associated differences and supports the use of BTBR mouse model to dissect autism associated microbiota-gut-brain axis alteration.

Sex differences in rhesus monkey toy preferences parallel those of children

PubMed Central

Hassett, Janice M.; Siebert, Erin R.; Wallen, Kim

2008-01-01

Socialization processes, parents, or peers encouraging play with gender specific toys are thought to be the primary force shaping sex differences in toy preference. A contrast in view is that toy preferences reflect biologically determined preferences for specific activities facilitated by specific toys. Sex differences in juvenile activities, such as rough and tumble play, peer preferences, and infant interest, share similarities in humans and monkeys. Thus if activity preferences shape toy preferences, male and female monkeys may show toy preferences similar to those seen in boys and girls. We compared the interactions of 34 rhesus monkeys, living within a 135 monkey troop, with human wheeled toys and plush toys. Male monkeys, like boys, showed consistent and strong preferences for wheeled toys, while female monkeys, like girls, showed greater variability in preferences. Thus, the magnitude of preference for wheeled over plush toys differed significantly between males and females. The similarities to human findings demonstrate that such preferences can develop without explicit gendered socialization. We offer the hypothesis that toy preferences reflect hormonally influenced behavioral and cognitive biases which are sculpted by social processes into the sex differences seen in monkeys and humans. PMID:18452921

Sex-specific early survival drives adult sex ratio bias in snowy plovers and impacts mating system and population growth

PubMed Central

Küpper, Clemens; Miller, Tom E. X.; Cruz-López, Medardo; Maher, Kathryn H.; dos Remedios, Natalie; Stoffel, Martin A.; Hoffman, Joseph I.; Krüger, Oliver; Székely, Tamás

2017-01-01

Adult sex ratio (ASR) is a central concept in population biology and a key factor in sexual selection, but why do most demographic models ignore sex biases? Vital rates often vary between the sexes and across life history, but their relative contributions to ASR variation remain poorly understood—an essential step to evaluate sex ratio theories in the wild and inform conservation. Here, we combine structured two-sex population models with individual-based mark–recapture data from an intensively monitored polygamous population of snowy plovers. We show that a strongly male-biased ASR (0.63) is primarily driven by sex-specific survival of juveniles rather than adults or dependent offspring. This finding provides empirical support for theories of unbiased sex allocation when sex differences in survival arise after the period of parental investment. Importantly, a conventional model ignoring sex biases significantly overestimated population viability. We suggest that sex-specific population models are essential to understand the population dynamics of sexual organisms: reproduction and population growth are most sensitive to perturbations in survival of the limiting sex. Overall, our study suggests that sex-biased early survival may contribute toward mating system evolution and population persistence, with implications for both sexual selection theory and biodiversity conservation. PMID:28634289

Sex-specific predictors of inpatient rehabilitation outcomes after traumatic brain injury

PubMed Central

Chan, Vincy; Mollayeva, Tatyana; Ottenbacher, Kenneth J.; Colantonio, Angela

2016-01-01

Objective To identify sex-specific predictors of inpatient rehabilitation outcomes among patients with a traumatic brain injury (TBI) from a population based perspective. Design Retrospective cohort study Setting Ontario, Canada Participants Patients in inpatient rehabilitation for a TBI within one year of acute care discharge between 2008/09 and 2011/12 (N=1,730, 70% male, 30% female). Interventions None Main Outcome Measures Inpatient rehabilitation length of stay, total Functional Independence Measure (FIM™) score, and motor and cognitive FIM™ ratings at discharge. Results Sex, as a covariate in multivariable linear regression models, was not a significant predictor of rehabilitation outcomes. While many of the predictors examined were similar across males and females, sex-specific multivariable models identified some predictors of rehabilitation outcome that are specific for males and females; mechanism of injury (p<.0001) was a significant predictor of functional outcome only among females while comorbidities (p<.0001) was a significant predictor for males only. Conclusions Predictors of outcomes after inpatient rehabilitation differed by sex, providing evidence for a sex-specific approach in planning and resource allocation for inpatient rehabilitation services for patients with TBI. PMID:26836952

Sex-Specific Predictors of Inpatient Rehabilitation Outcomes After Traumatic Brain Injury.

PubMed

Chan, Vincy; Mollayeva, Tatyana; Ottenbacher, Kenneth J; Colantonio, Angela

2016-05-01

To identify sex-specific predictors of inpatient rehabilitation outcomes among patients with a traumatic brain injury (TBI) from a population-based perspective. Retrospective cohort study. Inpatient rehabilitation. Patients in inpatient rehabilitation for a TBI within 1 year of acute care discharge between 2008/2009 and 2011/2012 (N=1730, 70% men, 30% women). None. Inpatient rehabilitation length of stay, total FIM score, and motor and cognitive FIM ratings at discharge. Sex, as a covariate in multivariable linear regression models, was not a significant predictor of rehabilitation outcomes. Although many of the predictors examined were similar across men and women, sex-specific multivariable models identified some predictors of rehabilitation outcome that are specific for men and women; mechanism of injury (P<.0001) was a significant predictor of functional outcome only among women, whereas comorbidities (P<.0001) was a significant predictor for men only. Predictors of outcomes after inpatient rehabilitation differed by sex, providing evidence for a sex-specific approach in planning and resource allocation for inpatient rehabilitation services for patients with TBI. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Evidence for sex-specific selection in brain: a case study of the nine-spined stickleback.

PubMed

Herczeg, G; Välimäki, K; Gonda, A; Merilä, J

2014-08-01

Theory predicts that the sex making greater investments into reproductive behaviours demands higher cognitive ability, and as a consequence, larger brains or brain parts. Further, the resulting sexual dimorphism can differ between populations adapted to different environments, or among individuals developing under different environmental conditions. In the nine-spine stickleback (Pungitius pungitius), males perform nest building, courtship, territory defence and parental care, whereas females perform mate choice and produce eggs. Also, predation-adapted marine and competition-adapted pond populations have diverged in a series of ecologically relevant traits, including the level of phenotypic plasticity. Here, we studied sexual dimorphism in brain size and architecture in nine-spined stickleback from marine and pond populations reared in a factorial experiment with predation and food treatments in a common garden experiment. Males had relatively larger brains, larger telencephala, cerebella and hypothalami (6-16% divergence) than females, irrespective of habitat. Females tended to have larger bulbi olfactorii than males (13%) in the high food treatment, whereas no such difference was found in the low food treatment. The strong sexual dimorphism in brain architecture implies that the different reproductive allocation strategies (behaviour vs. egg production) select for different investments into the costly brains between males and females. The lack of habitat dependence in brain sexual dimorphism suggests that the sex-specific selection forces on brains differ only negligibly between habitats. Although significance of the observed sex-specific brain plasticity in the size of bulbus olfactorius remains unclear, it demonstrates the potential for sex-specific neural plasticity. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Systematic, genome-wide, sex-specific linkage of cardiovascular traits in French Canadians.

PubMed

Seda, Ondrej; Tremblay, Johanne; Gaudet, Daniel; Brunelle, Pierre-Luc; Gurau, Alexandru; Merlo, Ettore; Pilote, Louise; Orlov, Sergei N; Boulva, Francis; Petrovich, Milan; Kotchen, Theodore A; Cowley, Allen W; Hamet, Pavel

2008-04-01

The sexual dimorphism of cardiovascular traits, as well as susceptibility to a variety of related diseases, has long been recognized, yet their sex-specific genomic determinants are largely unknown. We systematically assessed the sex-specific heritability and linkage of 539 hemodynamic, metabolic, anthropometric, and humoral traits in 120 French-Canadian families from the Saguenay-Lac-St-Jean region of Quebec, Canada. We performed multipoint linkage analysis using microsatellite markers followed by peak-wide linkage scan based on Affymetrix Human Mapping 50K Array Xba240 single nucleotide polymorphism genotypes in 3 settings, including the entire sample and then separately in men and women. Nearly one half of the traits were age and sex independent, one quarter were both age and sex dependent, and one eighth were exclusively age or sex dependent. Sex-specific phenotypes are most frequent in heart rate and blood pressure categories, whereas sex- and age-independent determinants are predominant among humoral and biochemical parameters. Twenty sex-specific loci passing multiple testing criteria were corroborated by 2-point single nucleotide polymorphism linkage. Several resting systolic blood pressure measurements showed significant genotype-by-sex interaction, eg, male-specific locus at chromosome 12 (male-female logarithm of odds difference: 4.16; interaction P=0.0002), which was undetectable in the entire population, even after adjustment for sex. Detailed interrogation of this locus revealed a 220-kb block overlapping parts of TAO-kinase 3 and SUDS3 genes. In summary, a large number of complex cardiovascular traits display significant sexual dimorphism, for which we have demonstrated genomic determinants at the haplotype level. Many of these would have been missed in a traditional, sex-adjusted setting.

Invited review: sex ratio and rheumatic disease.

PubMed

Lockshin, M D

2001-11-01

Human illnesses affect men and women differently. In some cases (diseases of sex organs, diseases resulting from X or Y chromosome mutations), reasons for sex discrepancy are obvious, but in other cases no reason is apparent. Explanations for sex discrepancy of illness occur at different biological levels: molecular (e.g., imprinting, X-inactivation), cellular (sex-specific receptor activity), organ (endocrine influences), whole organism (size, age), and environmental-behavioral, including intrauterine influences. Autoimmunity represents a prototypical class of illness that has high female-to-male (F/M) ratios. Although the F/M ratios in autoimmune diseases are usually attributed to the influence of estrogenic hormones, evidence demonstrates that the attributed ratios are imprecise and that definitions and classifications of autoimmune diseases vary, rendering at least part of the counting imprecise. In addition, many studies on sex discrepancy of human disease fail to distinguish between disease incidence and disease severity. In April 2001, the Institute of Medicine of the National Academy of Sciences published Exploring the Biological Contributions to Human Health: Does Sex Matter? (Wizemann T and Pardue M-L, editors). This minireview summarizes the section of that report that concerns autoimmune and infectious disease. Some thyroid, rheumatic, and hepatic autoimmune diseases have high F/M ratios, whereas others have low. Those that have high ratios occur primarily in young adulthood. Gonadal hormones, if they play a role, likely do so through a threshold or permissive mechanism. Examples of sex differences that could be caused by environmental exposure, X inactivation, imprinting, X or Y chromosome genetic modulators, and intrauterine influences are presented as alternate, theoretical, and largely unexplored explanations for sex differences of incidence. The epidemiology of autoimmune diseases (young, female) suggests that an explanation for sex discrepancy of these illnesses lies in differential exposure, vulnerable periods, or thresholds. Biologists have an opportunity to inform medical scientists about sex differences that explain different attack rates in specific diseases, and physicians offer biologists experiments of nature to test theories of sex.

Sex-specific genetic variance and the evolution of sexual dimorphism: a systematic review of cross-sex genetic correlations.

PubMed

Poissant, Jocelyn; Wilson, Alastair J; Coltman, David W

2010-01-01

The independent evolution of the sexes may often be constrained if male and female homologous traits share a similar genetic architecture. Thus, cross-sex genetic covariance is assumed to play a key role in the evolution of sexual dimorphism (SD) with consequent impacts on sexual selection, population dynamics, and speciation processes. We compiled cross-sex genetic correlations (r(MF)) estimates from 114 sources to assess the extent to which the evolution of SD is typically constrained and test several specific hypotheses. First, we tested if r(MF) differed among trait types and especially between fitness components and other traits. We also tested the theoretical prediction of a negative relationship between r(MF) and SD based on the expectation that increases in SD should be facilitated by sex-specific genetic variance. We show that r(MF) is usually large and positive but that it is typically smaller for fitness components. This demonstrates that the evolution of SD is typically genetically constrained and that sex-specific selection coefficients may often be opposite in sign due to sub-optimal levels of SD. Most importantly, we confirm that sex-specific genetic variance is an important contributor to the evolution of SD by validating the prediction of a negative correlation between r(MF) and SD.

Does the volatile hydrocarbon profile differ between the sexes: a case study on five aphidophagous ladybirds.

PubMed

Pattanayak, Rojalin; Mishra, Geetanjali; Omkar; Chanotiya, Chandan Singh; Rout, Prasant Kumar; Mohanty, Chandra Sekhar

2014-11-01

Insect hydrocarbons (HCs) primarily serve as a waterproofing cuticular layer and function extensively in chemical communication by facilitating species, sex, and colony recognition. In this study, headspace solid-phase microextraction is employed for investigating the sex-specific volatile HC profile of five ladybirds collected from Lucknow, India namely, Coccinella septempunctata (L.), Coccinella transversalis (Fabr.), Menochilus sexmaculatus (Fabr.), Propylea dissecta (Mulsant), and Anegleis cardoni (Weise) for the first time. Major compounds reported in C. septempunctata, C. transversalis, and A. cardoni are methyl-branched saturated HCs, whereas in M. sexmaculatus, and P. dissecta, they are unsaturated HCs. Other than A. cardoni, both the sexes of the other four ladybirds had similar compounds at highest peak but with statistically significant differences. However, in A. cardoni, which is a beetle with a narrow niche, the major compound in both male and female was different. The difference in volatile HC profile of the sexes of the five ladybirds indicates that gender-specific differences primarily exist due to quantitative differences in chemicals with only very few chemicals being unique to a gender. This variation in semiochemicals might have a role in behavioral or ecological aspects of the studied ladybirds. © 2014 Wiley Periodicals, Inc.

Report on the conference on 'Men, women, and medicine: a new view of the biology of sex/gender differences and aging' held in Berlin, 24-26th February 2006.

PubMed

Kampf, Antje

2006-10-26

The first world wide symposium on the topic of gender-specific medicine provided the latest research on differences in sex and/or gender in medicine and medical care. The presentations ranged beyond the topic of reproduction to encompass the entire human organism. This report critically reviews three issues that emerged during the Conference: gender mainstreaming, the concept of sex/gender differences and the issue of men's health. It suggests that the interdisciplinary concept of gender-specific medicine has to be mirrored by the integration of social and cultural studies into medical research and practice.

Influence of sex and stress exposure across the lifespan on endophenotypes of depression: focus on behavior, glucocorticoids, and hippocampus

PubMed Central

Gobinath, Aarthi R.; Mahmoud, Rand; Galea, Liisa A.M.

2015-01-01

Sex differences exist in vulnerability, symptoms, and treatment of many neuropsychiatric disorders. In this review, we discuss both preclinical and clinical research that investigates how sex influences depression endophenotypes at the behavioral, neuroendocrine, and neural levels across the lifespan. Chronic exposure to stress is a risk factor for depression and we discuss how stress during the prenatal, postnatal, and adolescent periods differentially affects males and females depending on the method of stress and metric examined. Given that the integrity of the hippocampus is compromised in depression, we specifically focus on sex differences in how hippocampal plasticity is affected by stress and depression across the lifespan. In addition, we examine how female physiology predisposes depression in adulthood, specifically in postpartum and perimenopausal periods. Finally, we discuss the underrepresentation of women in both preclinical and clinical research and how this limits our understanding of sex differences in vulnerability, presentation, and treatment of depression. PMID:25610363

Sex Differences in Drug-Related Stress-System Changes: Implications for Treatment in Substance-Abusing Women

PubMed Central

Fox, Helen C.; Sinha, Rajita

2009-01-01

Extensive research indicates that chronic substance abuse disrupts stress and reward systems of the brain. Gender variation within these stress-system alterations, including the impact of sex hormones on these changes, may influence sex-specific differences in both the development of, and recovery from, dependency. As such, gender variations in stress-system function may also provide a viable explanation for why women are markedly more vulnerable than men to the negative consequences of drug use. This article therefore initially reviews studies that have examined gender differences in emotional and biophysiological changes to the stress and reward system following the acute administration of drugs, including cocaine, alcohol, and nicotine. The article then reviews studies that have examined gender differences in response to various types of stress in both healthy and drug-abusing populations. Studies examining the impact of sex hormones on these gender-related responses are also reported. The implications of these sex-specific variations in stress and reward system function are discussed in terms of both comorbid psychopathology and treatment outcome. PMID:19373619

The Vanderbilt Expertise Test Reveals Domain-General and Domain-Specific Sex Effects in Object Recognition

PubMed Central

McGugin, Rankin W.; Richler, Jennifer J.; Herzmann, Grit; Speegle, Magen; Gauthier, Isabel

2012-01-01

Individual differences in face recognition are often contrasted with differences in object recognition using a single object category. Likewise, individual differences in perceptual expertise for a given object domain have typically been measured relative to only a single category baseline. In Experiment 1, we present a new test of object recognition, the Vanderbilt Expertise Test (VET), which is comparable in methods to the Cambridge Face Memory Task (CFMT) but uses eight different object categories. Principal component analysis reveals that the underlying structure of the VET can be largely explained by two independent factors, which demonstrate good reliability and capture interesting sex differences inherent in the VET structure. In Experiment 2, we show how the VET can be used to separate domain-specific from domain-general contributions to a standard measure of perceptual expertise. While domain-specific contributions are found for car matching for both men and women and for plane matching in men, women in this sample appear to use more domain-general strategies to match planes. In Experiment 3, we use the VET to demonstrate that holistic processing of faces predicts face recognition independently of general object recognition ability, which has a sex-specific contribution to face recognition. Overall, the results suggest that the VET is a reliable and valid measure of object recognition abilities and can measure both domain-general skills and domain-specific expertise, which were both found to depend on the sex of observers. PMID:22877929

Sex work and the construction of intimacies: meanings and work pragmatics in rural Malawi

PubMed Central

Tavory, Iddo; Poulin, Michelle

2017-01-01

This article focuses on Malawian sex workers’ understandings of exchange and intimacy, showing how multiple historically emergent categories and specific work pragmatics produce specific patterns of relational meanings. As we show, sex workers make sense of their relationships with clients through two categories. The first is sex work; the second is the chibwenzi, an intimate premarital relational category that emerged from pre-colonial transformations in courtship practices. These categories, in turn, are also shaped differently in different work settings. We use narratives from in-depth interviews with 45 sex workers and bar managers in southern Malawi to describe how the everyday pragmatics of two forms of sex work—performed by “bargirls” and “freelancers”—foster distinct understandings of relationships between them and men they have sex with. Bargirls, who work and live in bars, blurred the boundaries between “regulars” and chibwenzi; freelancers, who are not tethered to a specific work environment, often subverted the meanings of the chibwenzi, presenting these relationships as both intimate and emotionally distant. Through this comparison, we thus refine an approach to the study of the intimacy-exchange nexus, and use it to capture the complexities of gender relations in post-colonial Malawi. PMID:28936026

Sex Differences in Psychiatric Disease: A Focus on the Glutamate System

PubMed Central

Wickens, Megan M.; Bangasser, Debra A.; Briand, Lisa A.

2018-01-01

Alterations in glutamate, the primary excitatory neurotransmitter in the brain, are implicated in several psychiatric diseases. Many of these psychiatric diseases display epidemiological sex differences, with either males or females exhibiting different symptoms or disease prevalence. However, little work has considered the interaction of disrupted glutamatergic transmission and sex on disease states. This review describes the clinical and preclinical evidence for these sex differences with a focus on two conditions that are more prevalent in women: Alzheimer's disease and major depressive disorder, and three conditions that are more prevalent in men: schizophrenia, autism spectrum disorder, and attention deficit hyperactivity disorder. These studies reveal sex differences at multiple levels in the glutamate system including metabolic markers, receptor levels, genetic interactions, and therapeutic responses to glutamatergic drugs. Our survey of the current literature revealed a considerable need for more evaluations of sex differences in future studies examining the role of the glutamate system in psychiatric disease. Gaining a more thorough understanding of how sex differences in the glutamate system contribute to psychiatric disease could provide novel avenues for the development of sex-specific pharmacotherapies.

Sex/Gender Differences and Autism: Setting the Scene for Future Research

PubMed Central

Lai, Meng-Chuan; Lombardo, Michael V.; Auyeung, Bonnie; Chakrabarti, Bhismadev; Baron-Cohen, Simon

2015-01-01

Objective The relationship between sex/gender differences and autism has attracted a variety of research ranging from clinical and neurobiological to etiological, stimulated by the male bias in autism prevalence. Findings are complex and do not always relate to each other in a straightforward manner. Distinct but interlinked questions on the relationship between sex/gender differences and autism remain underaddressed. To better understand the implications from existing research and to help design future studies, we propose a 4-level conceptual framework to clarify the embedded themes. Method We searched PubMed for publications before September 2014 using search terms “‘sex OR gender OR females’ AND autism.” A total of 1,906 articles were screened for relevance, along with publications identified via additional literature reviews, resulting in 329 articles that were reviewed. Results Level 1, “Nosological and diagnostic challenges,” concerns the question, “How should autism be defined and diagnosed in males and females?” Level 2, “Sex/gender-independent and sex/gender-dependent characteristics,” addresses the question, “What are the similarities and differences between males and females with autism?” Level 3, “General models of etiology: liability and threshold,” asks the question, “How is the liability for developing autism linked to sex/gender?” Level 4, “Specific etiological–developmental mechanisms,” focuses on the question, “What etiological–developmental mechanisms of autism are implicated by sex/gender and/or sexual/gender differentiation?” Conclusions Using this conceptual framework, findings can be more clearly summarized, and the implications of the links between findings from different levels can become clearer. Based on this 4-level framework, we suggest future research directions, methodology, and specific topics in sex/gender differences and autism. PMID:25524786

Effects of biological sex on the pathophysiology of the heart.

PubMed

Fazal, Loubina; Azibani, Feriel; Vodovar, Nicolas; Cohen Solal, Alain; Delcayre, Claude; Samuel, Jane-Lise

2014-02-01

Cardiovascular diseases are the leading causes of death in men and women in industrialized countries. While the effects of biological sex on cardiovascular pathophysiology have long been known, the sex-specific mechanisms mediating these processes have been further elucidated over recent years. This review aims at analysing the sex-based differences in cardiac structure and function in adult mammals, and the sex-based differences in the main molecular mechanisms involved in the response of the heart to pathological situations. It emerged from this review that the sex-based difference is a variable that should be dealt with, not only in basic science or clinical research, but also with regards to therapeutic approaches. © 2013 The British Pharmacological Society.

Intra- Versus Intersex Aggression: Testing Theories of Sex Differences Using Aggression Networks.

PubMed

Wölfer, Ralf; Hewstone, Miles

2015-08-01

Two theories offer competing explanations of sex differences in aggressive behavior: sexual-selection theory and social-role theory. While each theory has specific strengths and limitations depending on the victim's sex, research hardly differentiates between intrasex and intersex aggression. In the present study, 11,307 students (mean age = 14.96 years; 50% girls, 50% boys) from 597 school classes provided social-network data (aggression and friendship networks) as well as physical (body mass index) and psychosocial (gender and masculinity norms) information. Aggression networks were used to disentangle intra- and intersex aggression, whereas their class-aggregated sex differences were analyzed using contextual predictors derived from sexual-selection and social-role theories. As expected, results revealed that sexual-selection theory predicted male-biased sex differences in intrasex aggression, whereas social-role theory predicted male-biased sex differences in intersex aggression. Findings suggest the value of explaining sex differences separately for intra- and intersex aggression with a dual-theory framework covering both evolutionary and normative components. © The Author(s) 2015.

Sex Differences in Trauma-Related Psychopathology: a Critical Review of Neuroimaging Literature (2014-2017).

PubMed

Helpman, Liat; Zhu, Xi; Suarez-Jimenez, Benjamin; Lazarov, Amit; Monk, Catherine; Neria, Yuval

2017-11-08

Sex differences in the epidemiology and clinical presentation of trauma-related psychopathology have long been documented. Multiple underlying mechanisms have been examined, both psychosocial and biological. Among the most promising biological mechanisms are neural substrates of trauma-related psychopathology that have been uncovered in recent years. Neuroimaging studies of sex-related heterogeneity published over the past 3 years (2014-2017) demonstrate an interaction between sex and type, timing, and load of trauma exposure. These studies suggest that, for males, early trauma exposure may involve a loss of gray matter in the limbic system, including the prefrontal cortex (PFC), amygdala, and hippocampus, and an over-activity and increased connectivity of salience hubs, and particularly dorsal anterior cingulate cortex (dACC). For females, however, early trauma exposure may involve overactive and possibly an enlarged amygdala, as well as decreased connectivity of salience hubs such as the dACC. Underlying mechanisms may include interaction with several endocrine systems and result in differential neural response to naturally occurring and added endocrine ligands, as well as sex-specific genetic and epigenetic risk and resilience factors. This complex interaction between multiple biological systems may be associated with sex-specific behavioral patterns, in turn associated with trauma-related psychopathology. While substantial number of published studies present preliminary evidence for neural mechanisms of sex-specific posttraumatic responses, there is a paucity of research directly designed to examine sex as a biological factor in trauma-related psychopathology. Specific foci for future studies aiming to bridge current gaps in the literature are discussed.

University Student Beliefs about Sex: Men vs. Women

ERIC Educational Resources Information Center

Knox, David; Zusman, Marty; McNeely, Andrea

2008-01-01

Analysis of survey data from 326 undergraduates at a large southeastern university revealed significant differences between men and women in their sexual beliefs. Specifically, men were more likely to think that oral sex is not sex; that cybersex is not cheating, that men can't tell if a woman is faking orgasm and that sex frequency drops in…

Sex differences and stress across the lifespan

PubMed Central

Bale, Tracy L; Epperson, C Neill

2015-01-01

Sex differences in stress responses can be found at all stages of life and are related to both the organizational and activational effects of gonadal hormones and to genes on the sex chromosomes. As stress dysregulation is the most common feature across neuropsychiatric diseases, sex differences in how these pathways develop and mature may predict sex-specific periods of vulnerability to disruption and increased disease risk or resilience across the lifespan. The aging brain is also at risk to the effects of stress, where the rapid decline of gonadal hormones in women combined with cellular aging processes promote sex biases in stress dysregulation. In this Review, we discuss potential underlying mechanisms driving sex differences in stress responses and their relevance to disease. Although stress is involved in a much broader range of diseases than neuropsychiatric ones, we highlight here this area and its examples across the lifespan. PMID:26404716

Sex differences and stress across the lifespan.

PubMed

Bale, Tracy L; Epperson, C Neill

2015-10-01

Sex differences in stress responses can be found at all stages of life and are related to both the organizational and activational effects of gonadal hormones and to genes on the sex chromosomes. As stress dysregulation is the most common feature across neuropsychiatric diseases, sex differences in how these pathways develop and mature may predict sex-specific periods of vulnerability to disruption and increased disease risk or resilience across the lifespan. The aging brain is also at risk to the effects of stress, where the rapid decline of gonadal hormones in women combined with cellular aging processes promote sex biases in stress dysregulation. In this Review, we discuss potential underlying mechanisms driving sex differences in stress responses and their relevance to disease. Although stress is involved in a much broader range of diseases than neuropsychiatric ones, we highlight here this area and its examples across the lifespan.

Sex-Specific Differences in Agonistic Behaviour, Sound Production and Auditory Sensitivity in the Callichthyid Armoured Catfish Megalechis thoracata

PubMed Central

Hadjiaghai, Oliwia; Ladich, Friedrich

2015-01-01

Background Data on sex-specific differences in sound production, acoustic behaviour and hearing abilities in fishes are rare. Representatives of numerous catfish families are known to produce sounds in agonistic contexts (intraspecific aggression and interspecific disturbance situations) using their pectoral fins. The present study investigates differences in agonistic behaviour, sound production and hearing abilities in males and females of a callichthyid catfish. Methodology/Principal Findings Eight males and nine females of the armoured catfish Megalechis thoracata were investigated. Agonistic behaviour displayed during male-male and female-female dyadic contests and sounds emitted were recorded, sound characteristics analysed and hearing thresholds measured using the auditory evoked potential (AEP) recording technique. Male pectoral spines were on average 1.7-fold longer than those of same-sized females. Visual and acoustic threat displays differed between sexes. Males produced low-frequency harmonic barks at longer distances and thumps at close distances, whereas females emitted broad-band pulsed crackles when close to each other. Female aggressive sounds were significantly shorter than those of males (167 ms versus 219 to 240 ms) and of higher dominant frequency (562 Hz versus 132 to 403 Hz). Sound duration and sound level were positively correlated with body and pectoral spine length, but dominant frequency was inversely correlated only to spine length. Both sexes showed a similar U-shaped hearing curve with lowest thresholds between 0.2 and 1 kHz and a drop in sensitivity above 1 kHz. The main energies of sounds were located at the most sensitive frequencies. Conclusions/Significance Current data demonstrate that both male and female M. thoracata produce aggressive sounds, but the behavioural contexts and sound characteristics differ between sexes. Sexes do not differ in hearing, but it remains to be clarified if this is a general pattern among fish. This is the first study to describe sex-specific differences in agonistic behaviour in fishes. PMID:25775458

Sex-specific divergence for adaptations to dehydration stress in Drosophila kikkawai.

PubMed

Parkash, Ravi; Ranga, Poonam

2013-09-01

Several studies on diverse Drosophila species have reported higher desiccation resistance of females, but the physiological basis of such sex-specific differences has received less attention. We tested whether sex-specific differences in cuticular traits (melanic females and non-melanic males) of Drosophila kikkawai correspond with divergence in their water balance mechanisms. Our results are interesting in several respects. First, positive clinal variation in desiccation resistance was correlated with cuticular melanisation in females but with changes in cuticular lipid mass in males, despite a lack of differences between the sexes for the rate of water loss. Second, a comparative analysis of water budget showed that females of the northern population stored more body water as well as hemolymph content and exhibited greater dehydration tolerance than flies from the southern tropics. In contrast, we found no geographical variation in the males for water content and dehydration tolerance. Third, an ~10-fold increase in the rate of water loss after organic solvent treatment of male D. kikkawai suggested a role of cuticular lipids in cuticular transpiration, but had no effect in the females. Fourth, geographical differences in the storage of carbohydrate content (metabolic fuel) were observed in females but not in males. Interestingly, in females, the rate of utilization of carbohydrates did not vary geographically, but males from drier localities showed a 50% reduction compared with wetter localities. Thus, body melanisation, increased body water, hemolymph, carbohydrate content and greater dehydration tolerance confer greater desiccation resistance in females, but a reduced rate of water loss is the only possible mechanism to cope with drought stress in males. Finally, acclimated females showed a significant increase in drought resistance associated with higher trehalose content as well as dehydration tolerance, while males showed no acclimation response. Thus, sex-specific differences in desiccation resistance of D. kikkawai are associated with divergence in some water balance strategies, despite a lack of differences in the rate of water loss between the two sexes.

Gender differences in brain structure and resting-state functional connectivity related to narcissistic personality.

PubMed

Yang, Wenjing; Cun, Lingli; Du, Xue; Yang, Junyi; Wang, Yanqiu; Wei, Dongtao; Zhang, Qinglin; Qiu, Jiang

2015-06-25

Although cognitive and personality studies have observed gender differences in narcissism, the neural bases of these differences remain unknown. The current study combined the voxel-based morphometry and resting state functional connectivity (rsFC) analyses to explore the sex-specific neural basis of narcissistic personality. The VBM results showed that the relationship between narcissistic personality and regional gray matter volume (rGMV) differed between sexes. Narcissistic scores had a significant positive correlation with the rGMV of the right SPL in females, but not in males. Further analyses were conducted to investigate the sex-specific relationship between rsFC and narcissism, using right SPL/frontal eye fields (FEF) as the seed regions (key nodes of the dorsal attention network, DAN). Interestingly, decreased anticorrelations between the right SPL/FEF and areas of the precuneus and middle frontal gyrus (key nodes of the the default mode network, DMN) were associated with higher narcissistic personality scores in males, whereas females showed the opposite tendency. The findings indicate that gender differences in narcissism may be associated with differences in the intrinsic and dynamic interplay between the internally-directed DMN and the externally-directed TPN. Morphometry and functional connectivity analyses can enhance our understanding of the neural basis of sex-specific narcissism.

Forethought in Youth with Attention Deficit/Hyperactivity Disorder: An fMRI Study of Sex-Specific Differences.

PubMed

Poissant, H; Rapin, L; Chenail, S; Mendrek, A

2016-01-01

Objective. The majority of studies investigating neurocognitive processing in attention deficit/hyperactivity disorder (ADHD) have been conducted on male participants. Few studies evaluated females or examined sex differences. Among various cognitive anomalies in ADHD, deficit in forethought seems particularly important as children with ADHD often fail to adequately use previous information in order to prepare for responses. The main goal of this study was to assess sex-specific differences in behavioral and neural correlates of forethought in youth with ADHD. Methods. 21 typically developing (TD) youth and 23 youth with ADHD were asked to judge whether two pictures told a congruent or incongruent story. Reaction time, performance accuracy, and cerebral activations were recorded during functional magnetic resonance imaging (fMRI). Results. Significant sex-specific differences in cerebral activations appeared, despite equivalent performance. Relative to the boys TD participants, boys with ADHD had extensive bilateral frontal and parietal hypoactivations, while girls with ADHD demonstrated more scattered hypoactivations in the right cerebral regions. Conclusion. Present results revealed that youth with ADHD exhibit reduced cerebral activations during forethought. Nevertheless, the pattern of deficits differed between boys and girls, suggesting the use of a different neurocognitive strategy. This emphasizes the importance of including both genders in the investigations of ADHD.

Gender differences in brain structure and resting-state functional connectivity related to narcissistic personality

PubMed Central

Yang, Wenjing; Cun, Lingli; Du, Xue; Yang, Junyi; Wang, Yanqiu; Wei, Dongtao; Zhang, Qinglin; Qiu, Jiang

2015-01-01

Although cognitive and personality studies have observed gender differences in narcissism, the neural bases of these differences remain unknown. The current study combined the voxel-based morphometry and resting state functional connectivity (rsFC) analyses to explore the sex-specific neural basis of narcissistic personality. The VBM results showed that the relationship between narcissistic personality and regional gray matter volume (rGMV) differed between sexes. Narcissistic scores had a significant positive correlation with the rGMV of the right SPL in females, but not in males. Further analyses were conducted to investigate the sex-specific relationship between rsFC and narcissism, using right SPL/frontal eye fields (FEF) as the seed regions (key nodes of the dorsal attention network, DAN). Interestingly, decreased anticorrelations between the right SPL/FEF and areas of the precuneus and middle frontal gyrus (key nodes of the the default mode network, DMN) were associated with higher narcissistic personality scores in males, whereas females showed the opposite tendency. The findings indicate that gender differences in narcissism may be associated with differences in the intrinsic and dynamic interplay between the internally-directed DMN and the externally-directed TPN. Morphometry and functional connectivity analyses can enhance our understanding of the neural basis of sex-specific narcissism. PMID:26109334

Sex differences in prenatal epigenetic programming of stress pathways.

PubMed

Bale, Tracy L

2011-07-01

Maternal stress experience is associated with neurodevelopmental disorders including schizophrenia and autism. Recent studies have examined mechanisms by which changes in the maternal milieu may be transmitted to the developing embryo and potentially translated into programming of the epigenome. Animal models of prenatal stress have identified important sex- and temporal-specific effects on offspring stress responsivity. As dysregulation of stress pathways is a common feature in most neuropsychiatric diseases, molecular and epigenetic analyses at the maternal-embryo interface, especially in the placenta, may provide unique insight into identifying much-needed predictive biomarkers. In addition, as most neurodevelopmental disorders present with a sex bias, examination of sex differences in the inheritance of phenotypic outcomes may pinpoint gene targets and specific windows of vulnerability in neurodevelopment, which have been disrupted. This review discusses the association and possible contributing mechanisms of prenatal stress in programming offspring stress pathway dysregulation and the importance of sex.

Sex and gender in psychoneuroimmunology research: Past, present and future

PubMed Central

Darnall, Beth D.; Suarez, Edward C.

2009-01-01

To date, research suggests that sex and gender impact pathways central to the foci of psychoneuroimmunology (PNI). This review provides a historical perspective on the evolution of sex and gender in psychoneuroimmunology research. Gender and sexually dimorphic pathways may have synergistic effects on health differences in men and women. We provide an overview of the literature of sex and gender differences in brain structure and function, sex steroids, gender role identification, hypothalamic-pituitary-adrenal axis function, genetics, immunology and cytokine response. Specific examples shed light on the importance of attending to sex and gender methodology in PNI research and recommendations are provided. PMID:19272440

Sex and gender in psychoneuroimmunology research: past, present and future.

PubMed

Darnall, Beth D; Suarez, Edward C

2009-07-01

To date, research suggests that sex and gender impact pathways central to the foci of psychoneuroimmunology (PNI). This review provides a historical perspective on the evolution of sex and gender in psychoneuroimmunology research. Gender and sexually dimorphic pathways may have synergistic effects on health differences in men and women. We provide an overview of the literature of sex and gender differences in brain structure and function, sex steroids, gender role identification, hypothalamic-pituitary-adrenal axis function, genetics, immunology and cytokine response. Specific examples shed light on the importance of attending to sex and gender methodology in PNI research and recommendations are provided.

Development of a PubMed Based Search Tool for Identifying Sex and Gender Specific Health Literature.

PubMed

Song, Michael M; Simonsen, Cheryl K; Wilson, Joanna D; Jenkins, Marjorie R

2016-02-01

An effective literature search strategy is critical to achieving the aims of Sex and Gender Specific Health (SGSH): to understand sex and gender differences through research and to effectively incorporate the new knowledge into the clinical decision making process to benefit both male and female patients. The goal of this project was to develop and validate an SGSH literature search tool that is readily and freely available to clinical researchers and practitioners. PubMed, a freely available search engine for the Medline database, was selected as the platform to build the SGSH literature search tool. Combinations of Medical Subject Heading terms, text words, and title words were evaluated for optimal specificity and sensitivity. The search tool was then validated against reference bases compiled for two disease states, diabetes and stroke. Key sex and gender terms and limits were bundled to create a search tool to facilitate PubMed SGSH literature searches. During validation, the search tool retrieved 50 of 94 (53.2%) stroke and 62 of 95 (65.3%) diabetes reference articles selected for validation. A general keyword search of stroke or diabetes combined with sex difference retrieved 33 of 94 (35.1%) stroke and 22 of 95 (23.2%) diabetes reference base articles, with lower sensitivity and specificity for SGSH content. The Texas Tech University Health Sciences Center SGSH PubMed Search Tool provides higher sensitivity and specificity to sex and gender specific health literature. The tool will facilitate research, clinical decision-making, and guideline development relevant to SGSH.

Development of a PubMed Based Search Tool for Identifying Sex and Gender Specific Health Literature

PubMed Central

Song, Michael M.; Simonsen, Cheryl K.; Wilson, Joanna D.

2016-01-01

Abstract Background: An effective literature search strategy is critical to achieving the aims of Sex and Gender Specific Health (SGSH): to understand sex and gender differences through research and to effectively incorporate the new knowledge into the clinical decision making process to benefit both male and female patients. The goal of this project was to develop and validate an SGSH literature search tool that is readily and freely available to clinical researchers and practitioners. Methods: PubMed, a freely available search engine for the Medline database, was selected as the platform to build the SGSH literature search tool. Combinations of Medical Subject Heading terms, text words, and title words were evaluated for optimal specificity and sensitivity. The search tool was then validated against reference bases compiled for two disease states, diabetes and stroke. Results: Key sex and gender terms and limits were bundled to create a search tool to facilitate PubMed SGSH literature searches. During validation, the search tool retrieved 50 of 94 (53.2%) stroke and 62 of 95 (65.3%) diabetes reference articles selected for validation. A general keyword search of stroke or diabetes combined with sex difference retrieved 33 of 94 (35.1%) stroke and 22 of 95 (23.2%) diabetes reference base articles, with lower sensitivity and specificity for SGSH content. Conclusions: The Texas Tech University Health Sciences Center SGSH PubMed Search Tool provides higher sensitivity and specificity to sex and gender specific health literature. The tool will facilitate research, clinical decision-making, and guideline development relevant to SGSH. PMID:26555409

Region-specific associations between sex, social status, and oxytocin receptor density in the brains of eusocial rodents.

PubMed

Mooney, S J; Coen, C W; Holmes, M M; Beery, A K

2015-09-10

Naturally occurring variations in neuropeptide receptor distributions in the brain contribute to numerous mammalian social behaviors. In naked mole-rats, which live in large social groups and exhibit remarkable reproductive skew, colony-related social behaviors vary with reproductive status. Here we examined whether variation in social status is associated with variations in the location and/or density of oxytocin binding in this species. Autoradiography was performed to assess forebrain oxytocin receptor (OTR) densities in breeding and non-breeding naked mole-rats of both sexes. Overall, males exhibited higher OTR binding in the medial amygdala in comparison to females. While there were no main effects of reproductive status in any region, a sex difference in OTR binding in the nucleus accumbens was mediated by status. Specifically, breeding males tended to have more OTR binding than breeding females in the nucleus accumbens, while no sex difference was observed in subordinates. These effects suggest that oxytocin may act in a sex- and region-specific way that corresponds to reproductive status and associated social behaviors. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Sociodemographic and Psychiatric Diagnostic Predictors of 3-Year Incidence of DSM-IV Substance Use Disorders among Men and Women in the National Epidemiologic Survey on Alcohol and Related Conditions

PubMed Central

Goldstein, Risë B.; Smith, Sharon M.; Dawson, Deborah A.; Grant, Bridget F.

2016-01-01

Incidence rates of alcohol and drug use disorders (AUDs and DUDs) are consistently higher in men than women, but information on whether sociodemographic and psychiatric diagnostic predictors of AUD and DUD incidence differ by sex is limited. Using data from Waves 1 and 2 of the National Epidemiologic Survey on Alcohol and Related Conditions, sex-specific 3-year incidence rates of AUDs and DUDs among United States adults were compared by sociodemographic variables and baseline psychiatric disorders. Sex-specific logistic regression models estimated odds ratios for prediction of incident AUDs and DUDs, adjusting for potentially confounding baseline sociodemographic and diagnostic variables. Few statistically significant sex differences in predictive relationships were identified and those observed were generally modest. Prospective research is needed to identify predictors of incident DSM-5 AUDs and DUDs and their underlying mechanisms, including whether there is sex specificity by developmental phase, in the role of additional comorbidity in etiology and course, and in outcomes of prevention and treatment. PMID:26727008

Gender Differences in Empathic Sadness towards Persons of the Same- versus Other-sex during Adolescence.

PubMed

Stuijfzand, Suzannah; De Wied, Minet; Kempes, Maaike; Van de Graaff, Jolien; Branje, Susan; Meeus, Wim

Although gender differences in affective empathy are well established, evidence of gender differences in the development of affective empathy is inconsistent. Consideration of same-sex versus other-sex affective empathy may assist in elucidating these inconsistencies. Gender differences were investigated in the experience of empathic sadness towards same- versus other-sex targets. The relationships were studied cross-sectionally ( N  = 730) and longitudinally ( N  = 318) with Dutch adolescents using the empathic sadness scale of the Index of Empathy for Children and Adolescents (IECA; Bryant 1982). In both studies, female adolescents reported more empathic sadness than did male adolescents. Female targets also received more affective empathy than did male targets, and, more importantly, gender differences were observed in same-sex versus other-sex affective empathy. Specifically, in both studies male adolescents reported less empathic sadness towards same-sex than towards other-sex targets. In contrast, female adolescents reported more empathic sadness towards same-sex than towards other-sex targets in the cross-sectional study, and equal levels of empathic sadness towards both types of targets in the longitudinal study. Findings highlight the importance of considering same-sex versus other-sex affective empathy. Gender differences in same-sex and other-sex affective empathy have implications for assisting adolescents in social conflict resolution and interventions for bullying and aggressive behaviour in adolescence using empathy training.

Sex differences in the developing brain as a source of inherent risk.

PubMed

McCarthy, Margaret M

2016-12-01

Brain development diverges in males and females in response to androgen production by the fetal testis. This sexual differentiation of the brain occurs during a sensitive window and induces enduring neuroanatomical and physiological changes that profoundly impact behavior. What we know about the contribution of sex chromosomes is still emerging, highlighting the need to integrate multiple factors into understanding sex differences, including the importance of context. The cellular mechanisms are best modeled in rodents and have provided both unifying principles and surprising specifics. Markedly distinct signaling pathways direct differentiation in specific brain regions, resulting in mosaicism of relative maleness, femaleness, and sameness through-out the brain, while canalization both exaggerates and constrains sex differences. Non-neuronal cells and inflammatory mediators are found in greater number and at higher levels in parts of male brains. This higher baseline of inflammation is speculated to increase male vulnerability to developmental neuropsychiatric disorders that are triggered by inflammation.

Gaming for Safer Sex: Young German and Turkish People Report No Specific Culture-Related Preferences Toward Educational Games Promoting Safer Sex.

PubMed

Brüll, Phil; Ruiter, Robert A C; Wiers, Reinout W; Kok, Gerjo

2016-12-01

Comprehensive sex education programs specifically designed for adolescents and young adults that take into account gender norms and cultural background have shown promise as a means of countering the high sexually transmitted infection rate in young people. Recently, digital gaming interventions delivered on computers or mobile devices have emerged as another way to promote safer sex behavior in a young population. Tailoring these computer-based interventions to their target population has been recognized to increase positive behavior outcomes. In this qualitative study, we investigated whether young female and male adults from two different cultural backgrounds (all living in Germany) would have different preferences and needs in relation to an educational game promoting safer sex. We conducted four semistructured focus group interviews comprising open-ended questions with male and female participants who had either a German or a Turkish background. In total, 20 individuals, aged between 18 and 22 years, from two socially diverse and ethnically mixed vocational schools in Germany participated. Independent of cultural background and gender, participants preferred a real-world design with a first-person visual perspective over a fantasy-like third-person perspective. Furthermore, they preferred highly customizable avatars. All participants mentioned the importance of including an alcohol-intoxicated avatar and most participants wanted there to be additional information available about various safer sex approaches and about the use of different barrier protection methods. Males and females reported similar preferences for the design of an educational game promoting safer sex, with the only difference being exactly how the topic of having sexual intercourse should be addressed in the game. Males preferred a direct approach, whereas females had a preference for treating this subject more sympathetically. Educational games offer anonymity and can provide young people across different cultural backgrounds with gender-tailored opportunities to experiment with specific safer sex precautions in a nonthreatening virtual environment, free from unwanted parental control and peer monitoring.

Sex-specific phenotypes of hyperthyroidism and hypothyroidism in aged mice.

PubMed

Rakov, Helena; Engels, Kathrin; Hönes, Georg Sebastian; Brix, Klaudia; Köhrle, Josef; Moeller, Lars Christian; Zwanziger, Denise; Führer, Dagmar

2017-12-22

Sex and age play a role in the prevalence of thyroid dysfunction (TD), but their interrelationship for manifestation of hyper- and hypothyroidism is still not well understood. Using a murine model, we asked whether sex impacts the phenotypes of hyper- and hypothyroidism at two life stages. Hyper- and hypothyroidism were induced by i.p. T4 or MMI/ClO 4 -/LoI treatment over 7 weeks in 12- and 20-months-old female and male C57BL/6N mice. Control animals underwent PBS treatment (n = 7-11 animals/sex/treatment). Animals were investigated for impact of sex on body weight, food and water intake, body temperature, heart rate, behaviour (locomotor activity, motor coordination and strength) and serum thyroid hormone (TH) status. Distinct sex impact was found in eu- and hyperthyroid mice, while phenotypic traits of hypothyroidism were similar in male and female mice. No sex difference was found in TH status of euthyroid mice; however, T4 treatment resulted in twofold higher TT4, FT4 and FT3 serum concentrations in adult and old females compared to male animals. Hyperthyroid females consistently showed higher locomotor activity and better coordination but more impairment of muscle function by TH excess at adult age. Importantly and in contrast to male mice, adult and old hyperthyroid female mice showed increased body weight. Higher body temperature in female mice was confirmed in all age groups. No sex impact was found on heart rate irrespective of TH status in adult and old mice. By comparison of male and female mice with TD at two life stages, we found that sex modulates TH action in an organ- and function-specific manner. Sex differences were more pronounced under hyperthyroid conditions. Importantly, sex-specific differences in features of TD in adult and old mice were not conclusively explained by serum TH status in mice.

The effect of parasites on sex differences in selection.

PubMed

Sharp, N P; Vincent, C M

2015-04-01

The life history strategies of males and females are often divergent, creating the potential for sex differences in selection. Deleterious mutations may be subject to stronger selection in males, owing to sexual selection, which can improve the mean fitness of females and reduce mutation load in sexual populations. However, sex differences in selection might also maintain sexually antagonistic genetic variation, creating a sexual conflict load. The overall impact of separate sexes on fitness is unclear, but the net effect is likely to be positive when there is a large sex difference in selection against deleterious mutations. Parasites can also have sex-specific effects on fitness, and there is evidence that parasites can intensify the fitness consequences of deleterious mutations. Using lines that accumulated mutations for over 60 generations, we studied the effect of the pathogenic bacterium Pseudomonas aeruginosa on sex differences in selection in the fruit fly Drosophila melanogaster. Pseudomonas infection increased the sex difference in selection, but may also have weakened the intersexual correlation for fitness. Our results suggest that parasites may increase the benefits of sexual selection.

Sex-specific Linkage Scans in Opioid Dependence

PubMed Central

Yang, Bao-Zhu; Han, Shizhong; Kranzler, Henry R.; Palmer, Abraham A.; Gelernter, Joel

2017-01-01

Sex influences risk for opioid dependence (OD). We hypothesized that sex might interact with genetic loci that influence the risk for OD. Therefore we performed an analysis to identify sex-specific genomic susceptibility regions for OD using linkage. Over 6000 single nucleotide polymorphism (SNP) markers were genotyped for 1758 African- and European-American (AA and EA) individuals from 739 families, ascertained via affected sib-pairs with OD and/or cocaine dependence. Autosomewide non-parametric linkage scans, stratified by sex and population, were performed. We identified one significant linkage region, segregating with OD in EA men, at 71.1 cM on chromosome 4 (LOD=3.29; point-wise p=0.00005; empirical autosome-wide p=0.042), which significantly differed from the linkage signal at the same location in EA women (empirical p=0.002). Three suggestive linkage signals were identified at 181.3 cM on chromosome 7 (LOD=2.18), 104 cM on chromosome 11 (LOD=1.85), and 60.9 cM on chromosome 16 (LOD=1.93) in EA women. In AA men, four suggestive linkage signals were detected at 201.1 cM on chromosome 3 (LOD=2.32), 152.9 cM on chromosome 6 (LOD=1.86), 16.8 cM on chromosome 7 (LOD=1.95), and 36.1 cM on chromosome 17 (LOD=1.99). The significant region, mapping to 4q12-4q13.1, harbors several OD candidate genes with interconnected functionality, including VEGFR, CLOCK, PDCL2, NMU, NRSF, and IGFBP7. In conclusion, these results provide an evidence for the existence of sex-specific and population-specific differences in OD. Furthermore, these results provide positional information that will facilitate the use of targeted next-generation sequencing to search for genes that contribute to sex-specific differences in OD. PMID:27762075

Sex-specific linkage scans in opioid dependence.

PubMed

Yang, Bao-Zhu; Han, Shizhong; Kranzler, Henry R; Palmer, Abraham A; Gelernter, Joel

2017-04-01

Sex influences risk for opioid dependence (OD). We hypothesized that sex might interact with genetic loci that influence the risk for OD. Therefore we performed an analysis to identify sex-specific genomic susceptibility regions for OD using linkage. Over 6,000 single nucleotide polymorphism (SNP) markers were genotyped for 1,758 African- and European-American (AA and EA) individuals from 739 families, ascertained via affected sib-pairs with OD and/or cocaine dependence. Autosomewide non-parametric linkage scans, stratified by sex and population, were performed. We identified one significant linkage region, segregating with OD in EA men, at 71.1 cM on chromosome 4 (LOD = 3.29; point-wise P = 0.00005; empirical autosome-wide P = 0.042), which significantly differed from the linkage signal at the same location in EA women (empirical P = 0.002). Three suggestive linkage signals were identified at 181.3 cM on chromosome 7 (LOD = 2.18), 104 cM on chromosome 11 (LOD = 1.85), and 60.9 cM on chromosome 16 (LOD = 1.93) in EA women. In AA men, four suggestive linkage signals were detected at 201.1 cM on chromosome 3 (LOD = 2.32), 152.9 cM on chromosome 6 (LOD = 1.86), 16.8 cM on chromosome 7 (LOD = 1.95), and 36.1 cM on chromosome 17 (LOD = 1.99). The significant region, mapping to 4q12-4q13.1, harbors several OD candidate genes with interconnected functionality, including VEGFR, CLOCK, PDCL2, NMU, NRSF, and IGFBP7. In conclusion, these results provide an evidence for the existence of sex-specific and population-specific differences in OD. Furthermore, these results provide positional information that will facilitate the use of targeted next-generation sequencing to search for genes that contribute to sex-specific differences in OD. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Hepatic Long Intergenic Noncoding RNAs: High Promoter Conservation and Dynamic, Sex-Dependent Transcriptional Regulation by Growth Hormone

PubMed Central

Melia, Tisha; Hao, Pengying; Yilmaz, Feyza

2015-01-01

Long intergenic noncoding RNAs (lincRNAs) are increasingly recognized as key chromatin regulators, yet few studies have characterized lincRNAs in a single tissue under diverse conditions. Here, we analyzed 45 mouse liver RNA sequencing (RNA-Seq) data sets collected under diverse conditions to systematically characterize 4,961 liver lincRNAs, 59% of them novel, with regard to gene structures, species conservation, chromatin accessibility, transcription factor binding, and epigenetic states. To investigate the potential for functionality, we focused on the responses of the liver lincRNAs to growth hormone stimulation, which imparts clinically relevant sex differences to hepatic metabolism and liver disease susceptibility. Sex-biased expression characterized 247 liver lincRNAs, with many being nuclear RNA enriched and regulated by growth hormone. The sex-biased lincRNA genes are enriched for nearby and correspondingly sex-biased accessible chromatin regions, as well as sex-biased binding sites for growth hormone-regulated transcriptional activators (STAT5, hepatocyte nuclear factor 6 [HNF6], FOXA1, and FOXA2) and transcriptional repressors (CUX2 and BCL6). Repression of female-specific lincRNAs in male liver, but not that of male-specific lincRNAs in female liver, was associated with enrichment of H3K27me3-associated inactive states and poised (bivalent) enhancer states. Strikingly, we found that liver-specific lincRNA gene promoters are more highly species conserved and have a significantly higher frequency of proximal binding by liver transcription factors than liver-specific protein-coding gene promoters. Orthologs for many liver lincRNAs were identified in one or more supraprimates, including two rat lincRNAs showing the same growth hormone-regulated, sex-biased expression as their mouse counterparts. This integrative analysis of liver lincRNA chromatin states, transcription factor occupancy, and growth hormone regulation provides novel insights into the expression of sex-specific lincRNAs and their potential for regulation of sex differences in liver physiology and disease. PMID:26459762

Sex-specific modulation of juvenile social play behavior by vasopressin and oxytocin depends on social context

PubMed Central

Bredewold, Remco; Smith, Caroline J. W.; Dumais, Kelly M.; Veenema, Alexa H.

2014-01-01

We recently demonstrated that vasopressin (AVP) in the lateral septum modulates social play behavior differently in male and female juvenile rats. However, the extent to which different social contexts (i.e., exposure to an unfamiliar play partner in different environments) affect the regulation of social play remains largely unknown. Given that AVP and the closely related neuropeptide oxytocin (OXT) modulate social behavior as well as anxiety-like behavior, we hypothesized that these neuropeptides may regulate social play behavior differently in novel (novel cage) as opposed to familiar (home cage) social environments. Administration of the specific AVP V1a receptor (V1aR) antagonist (CH2)5Tyr(Me2)AVP into the lateral septum enhanced home cage social play behavior in males but reduced it in females, confirming our previous findings. These effects were context-specific because V1aR blockade did not alter novel cage social play behavior in either sex. Furthermore, social play in females was reduced by AVP in the novel cage and by OXT in the home cage. Additionally, females administered the specific OXT receptor antagonist desGly-NH2,d(CH2)5−[Tyr(Me)2,Thr4]OVT showed less social play in the novel as compared to the home cage. AVP enhanced anxiety-related behavior in males (tested on the elevated plus-maze), but failed to do so in females, suggesting that exogenous AVP alters social play and anxiety-related behavior via distinct and sex-specific mechanisms. Moreover, none of the other drug treatments that altered social play had an effect on anxiety, suggesting that these drug-induced behavioral alterations are relatively specific to social behavior. Overall, we showed that AVP and OXT systems in the lateral septum modulate social play in juvenile rats in neuropeptide-, sex- and social context-specific ways. These findings underscore the importance of considering not only sex, but also social context, in how AVP and OXT modulate social behavior. PMID:24982623

Sexual dimorphism in mammalian autosomal gene regulation is determined not only by Sry but by sex chromosome complement as well.

PubMed

Wijchers, Patrick J; Yandim, Cihangir; Panousopoulou, Eleni; Ahmad, Mushfika; Harker, Nicky; Saveliev, Alexander; Burgoyne, Paul S; Festenstein, Richard

2010-09-14

Differences between males and females are normally attributed to developmental and hormonal differences between the sexes. Here, we demonstrate differences between males and females in gene silencing using a heterochromatin-sensitive reporter gene. Using "sex-reversal" mouse models with varying sex chromosome complements, we found that this differential gene silencing was determined by X chromosome complement, rather than sex. Genome-wide transcription profiling showed that the expression of hundreds of autosomal genes was also sensitive to sex chromosome complement. These genome-wide analyses also uncovered a role for Sry in modulating autosomal gene expression in a sex chromosome complement-specific manner. The identification of this additional layer in the establishment of sexual dimorphisms has implications for understanding sexual dimorphisms in physiology and disease. Copyright © 2010 Elsevier Inc. All rights reserved.

Life-History and Spatial Determinants of Somatic Growth Dynamics in Komodo Dragon Populations

PubMed Central

Laver, Rebecca J.; Purwandana, Deni; Ariefiandy, Achmad; Imansyah, Jeri; Forsyth, David; Ciofi, Claudio; Jessop, Tim S.

2012-01-01

Somatic growth patterns represent a major component of organismal fitness and may vary among sexes and populations due to genetic and environmental processes leading to profound differences in life-history and demography. This study considered the ontogenic, sex-specific and spatial dynamics of somatic growth patterns in ten populations of the world’s largest lizard the Komodo dragon (Varanus komodoensis). The growth of 400 individual Komodo dragons was measured in a capture-mark-recapture study at ten sites on four islands in eastern Indonesia, from 2002 to 2010. Generalized Additive Mixed Models (GAMMs) and information-theoretic methods were used to examine how growth rates varied with size, age and sex, and across and within islands in relation to site-specific prey availability, lizard population density and inbreeding coefficients. Growth trajectories differed significantly with size and between sexes, indicating different energy allocation tactics and overall costs associated with reproduction. This leads to disparities in maximum body sizes and longevity. Spatial variation in growth was strongly supported by a curvilinear density-dependent growth model with highest growth rates occurring at intermediate population densities. Sex-specific trade-offs in growth underpin key differences in Komodo dragon life-history including evidence for high costs of reproduction in females. Further, inverse density-dependent growth may have profound effects on individual and population level processes that influence the demography of this species. PMID:23028983

Cryptic sexual dimorphism in spatial memory and hippocampal oxytocin receptors in prairie voles (Microtus ochrogaster).

PubMed

Rice, Marissa A; Hobbs, Lauren E; Wallace, Kelly J; Ophir, Alexander G

2017-09-01

Sex differences are well documented and are conventionally associated with intense sex-specific selection. For example, spatial memory is frequently better in males, presumably due to males' tendency to navigate large spaces to find mates. Alternatively, monogamy (in which sex-specific selection is relatively relaxed) should diminish or eliminate differences in spatial ability and the mechanisms associated with this behavior. Nevertheless, phenotypic differences between monogamous males and females persist, sometimes cryptically. We hypothesize that sex-specific cognitive demands are present in monogamous species that will influence neural and behavioral phenotypes. The effects of these demands should be observable in spatial learning performance and neural structures associated with spatial learning and memory. We analyzed spatial memory performance, hippocampal volume and cell density, and hippocampal oxytocin receptor (OTR) expression in the socially monogamous prairie vole. Compared to females, males performed better in a spatial memory and spatial learning test. Although we found no sex difference in hippocampal volume or cell density, male OTR density was significantly lower than females, suggesting that performance may be regulated by sub-cellular mechanisms within the hippocampus that are less obvious than classic neuroanatomical features. Our results suggest an expanded role for oxytocin beyond facilitating social interactions, which may function in part to integrate social and spatial information. Copyright © 2017 Elsevier Inc. All rights reserved.

Sex Differences in Device Therapy for Heart Failure: Utilization, Outcomes, and Adverse Events

PubMed Central

Herz, Naomi D.; Engeda, Joseph; Zusterzeel, Robbert; Sanders, William E.; O'Callaghan, Kathryn M.; Strauss, David G.; Jacobs, Samantha B.; Selzman, Kimberly A.; Piña, Ileana L.

2015-01-01

Abstract Background: Multiple studies of heart failure patients demonstrated significant improvement in exercise capacity, quality of life, cardiac left ventricular function, and survival from cardiac resynchronization therapy (CRT), but the underenrollment of women in these studies is notable. Etiological and pathophysiological differences may result in different outcomes in response to this treatment by sex. The observed disproportionate representation of women suggests that many women with heart failure either do not meet current clinical criteria to receive CRT in trials or are not properly recruited and maintained in these studies. Methods: We performed a systematic literature review through May 2014 of clinical trials and registries of CRT use that stratified outcomes by sex or reported percent women included. One-hundred eighty-three studies contained sex-specific information. Results: Ninety percent of the studies evaluated included ≤35% women. Fifty-six articles included effectiveness data that reported response with regard to specific outcome parameters. When compared with men, women exhibited more dramatic improvement in specific parameters. In the studies reporting hazard ratios for hospitalization or death, women generally had greater benefit from CRT. Conclusions: Our review confirms women are markedly underrepresented in CRT trials, and when a CRT device is implanted, women have a therapeutic response that is equivalent to or better than in men, while there is no difference in adverse events reported by sex. PMID:25793483

Sex and age differences in physical performance: A comparison of Army basic training and operational populations.

PubMed

Dada, Esther O; Anderson, Morgan K; Grier, Tyson; Alemany, Joseph A; Jones, Bruce H

2017-11-01

To determine the age- and sex-specific differences of physical fitness performances and Body Mass Index (BMI) in basic training and the operational Army. Cross-sectional Study. This secondary analysis utilizes retrospective surveys of U.S. Army Soldiers in Basic Combat Training (BCT) and operational units to compare physical performances between men and women as measured by the Army Physical Readiness Test (APFT). An ANOVA was used to compare mean differences in APFT results and BMI within sex-specific populations. A post hoc Tukey test identified specific mean differences. Adjusting for age, an ANCOVA was used to compare sex and occupation (infantry and non-infantry) differences in APFT results. Surveyed populations consisted of 2216 BCT Soldiers (1573 men and 643 women) and 5515 Operational Soldiers (4987 men and 528 women). Male and female operational Soldiers had greater muscular performance (79%-125% higher APFT push-ups, 66%-85% higher APFT sit-ups) and cardiorespiratory performance (22%-24% faster APFT 2-mile run times) than BCT Soldiers. Male BCT and operational Soldiers outperform their female counterparts on tests of muscular and cardiorespiratory endurance. Sex differences in physical performances attenuated among female Soldiers in operational units compared to BCT. Among male operational Soldiers, infantry Soldiers exhibited greater cardiorespiratory and muscular performance than non-infantry Soldiers. Higher BMI was associated with higher age groups, except for female BCT Soldiers. Gaps in cardiorespiratory and muscular performances between men and women should be addressed through targeted physical training programs that aim to minimize physiological differences. Published by Elsevier Ltd.

Differing Mechanisms Underlie Sexual Size-Dimorphism in Two Populations of a Sex-Changing Fish

PubMed Central

McCormick, Mark I.; Ryen, Christopher A.; Munday, Philip L.; Walker, Stefan P. W.

2010-01-01

Variability in the density of groups within a patchy environment lead to differences in interaction rates, growth dynamics and social organization. In protogynous hermaphrodites there are hypothesised trade-offs among sex-specific growth, reproductive output and mortality. When differences in density lead to changes to social organization the link between growth and the timing of sex-change is predicted to change. The present study explores this prediction by comparing the social organisation and sex-specific growth of two populations of a protogynous tropical wrasse, Halichoeres miniatus, which differ in density. At a low density population a strict harem structure was found, where males maintained a tight monopoly of access and spawning rights to females. In contrast, at a high density population a loosely organised system prevailed, where females could move throughout multiple male territories. Otolith microstructure revealed the species to be annual and deposit an otolith check associated with sex-change. Growth trajectories suggested that individuals that later became males in both populations underwent a growth acceleration at sex-change. Moreover, in the high density population, individuals that later became males were those individuals that had the largest otolith size at hatching and consistently deposited larger increments throughout early larval, juvenile and female life. This study demonstrates that previous growth history and growth rate changes associated with sex change can be responsible for the sexual dimorphism typically found in sex-changing species, and that the relative importance of these may be socially constrained. PMID:20485547

Effects of Sex Steroids in the Human Brain.

PubMed

Nguyen, Tuong-Vi; Ducharme, Simon; Karama, Sherif

2017-11-01

Sex steroids are thought to play a critical developmental role in shaping both cortical and subcortical structures in the human brain. Periods of profound changes in sex steroids invariably coincide with the onset of sex differences in mental health vulnerability, highlighting the importance of sex steroids in determining sexual differentiation of the brain. Yet, most of the evidence for the central effects of sex steroids relies on non-human studies, as several challenges have limited our understanding of these effects in humans: the lack of systematic assessment of the human sex steroid metabolome, the different developmental trajectories of specific sex steroids, the impact of genetic variation and epigenetic changes, and the plethora of interactions between sex steroids, sex chromosomes, neurotransmitters, and other hormonal systems. Here we review how multimodal strategies may be employed to bridge the gap between the basic and clinical understanding of sex steroid-related changes in the human brain.

Sex-Divergent Clinical Outcomes and Precision Medicine: An Important New Role for Institutional Review Boards and Research Ethics Committees.

PubMed

Segarra, Ignacio; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L

2017-01-01

The efforts toward individualized medicine have constantly increased in an attempt to improve treatment options. These efforts have led to the development of small molecules which target specific molecular pathways involved in cancer progression. We have reviewed preclinical studies of sunitinib that incorporate sex as a covariate to explore possible sex-based differences in pharmacokinetics and drug-drug interactions (DDI) to attempt a relationship with published clinical outputs. We observed that covariate sex is lacking in most clinical outcome reports and suggest a series of ethic-based proposals to improve research activities and identify relevant different sex outcomes. We propose a deeper integration of preclinical, clinical, and translational research addressing statistical and clinical significance jointly; to embed specific sex-divergent endpoints to evaluate possible gender differences objectively during all stages of research; to pay greater attention to sex-divergent outcomes in polypharmacy scenarios, DDI and bioequivalence studies; the clear reporting of preclinical and clinical findings regarding sex-divergent outcomes; as well as to encourage the active role of scientists and the pharmaceutical industry to foster a new scientific culture through their research programs, practice, and participation in editorial boards and Institutional Ethics Review Boards (IRBs) and Research Ethics Committees (RECs). We establish the IRB/REC as the centerpiece for the implementation of these proposals. We suggest the expansion of its competence to follow up clinical trials to ensure that sex differences are addressed and recognized; to engage in data monitoring committees to improve clinical research cooperation and ethically address those potential clinical outcome differences between male and female patients to analyze their social and clinical implications in research and healthcare policies.

Sex-Divergent Clinical Outcomes and Precision Medicine: An Important New Role for Institutional Review Boards and Research Ethics Committees

PubMed Central

Segarra, Ignacio; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L.

2017-01-01

The efforts toward individualized medicine have constantly increased in an attempt to improve treatment options. These efforts have led to the development of small molecules which target specific molecular pathways involved in cancer progression. We have reviewed preclinical studies of sunitinib that incorporate sex as a covariate to explore possible sex-based differences in pharmacokinetics and drug–drug interactions (DDI) to attempt a relationship with published clinical outputs. We observed that covariate sex is lacking in most clinical outcome reports and suggest a series of ethic-based proposals to improve research activities and identify relevant different sex outcomes. We propose a deeper integration of preclinical, clinical, and translational research addressing statistical and clinical significance jointly; to embed specific sex-divergent endpoints to evaluate possible gender differences objectively during all stages of research; to pay greater attention to sex-divergent outcomes in polypharmacy scenarios, DDI and bioequivalence studies; the clear reporting of preclinical and clinical findings regarding sex-divergent outcomes; as well as to encourage the active role of scientists and the pharmaceutical industry to foster a new scientific culture through their research programs, practice, and participation in editorial boards and Institutional Ethics Review Boards (IRBs) and Research Ethics Committees (RECs). We establish the IRB/REC as the centerpiece for the implementation of these proposals. We suggest the expansion of its competence to follow up clinical trials to ensure that sex differences are addressed and recognized; to engage in data monitoring committees to improve clinical research cooperation and ethically address those potential clinical outcome differences between male and female patients to analyze their social and clinical implications in research and healthcare policies. PMID:28785221

Sex differences in the effect of puberty on hippocampal morphology.

PubMed

Satterthwaite, Theodore D; Vandekar, Simon; Wolf, Daniel H; Ruparel, Kosha; Roalf, David R; Jackson, Chad; Elliott, Mark A; Bilker, Warren B; Calkins, Monica E; Prabhakaran, Karthik; Davatzikos, Christos; Hakonarson, Hakon; Gur, Raquel E; Gur, Ruben C

2014-03-01

Puberty is the defining process of adolescence, and is accompanied by divergent trajectories of behavior and cognition for males and females. Here we examine whether sex differences exist in the effect of puberty on the morphology of the hippocampus and amygdala. T1-weighted structural neuroimaging was performed in a sample of 524 pre- or postpubertal individuals ages 10 to 22 years. Hippocampal and amygdala volume and shape were quantified using the Functional Magnetic Resonance Imaging of the Brain (FMRIB) Software Library (FSL) FIRST procedure and scaled by intracranial volume. The effects on regional volume of age, sex, puberty, and their interactions were examined using linear regression. Postpubertal sex differences were examined using a vertex analysis. Prepubertal males and females had similar hippocampal volumes, whereas postpubertal females had significantly larger bilateral hippocampi, resulting in a significant puberty-by-sex interaction even when controlling for age and age-by-sex. This effect was regionally specific and was not apparent in the amygdala. Vertex analysis revealed that postpubertal differences were most prominent in the lateral aspect of the hippocampus bilaterally, corresponding to the CA1 subfield. These results establish that there are regionally specific sex differences in the effect of puberty on the hippocampus. These findings are relevant for the understanding of psychiatric disorders that have both hippocampal dysfunction and prominent gender disparities during adolescence. Copyright © 2014 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Sex-specific inhibition and stimulation of worker-reproductive transition in a termite.

PubMed

Sun, Qian; Haynes, Kenneth F; Hampton, Jordan D; Zhou, Xuguo

2017-09-06

In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.

Sex-specific inhibition and stimulation of worker-reproductive transition in a termite

NASA Astrophysics Data System (ADS)

Sun, Qian; Haynes, Kenneth F.; Hampton, Jordan D.; Zhou, Xuguo

2017-10-01

In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.

Sex-related alterations of gut microbiota composition in the BTBR mouse model of autism spectrum disorder

PubMed Central

Coretti, Lorena; Cristiano, Claudia; Florio, Ermanno; Scala, Giovanni; Lama, Adriano; Keller, Simona; Cuomo, Mariella; Russo, Roberto; Pero, Raffaela; Paciello, Orlando; Mattace Raso, Giuseppina; Meli, Rosaria; Cocozza, Sergio; Calignano, Antonio; Chiariotti, Lorenzo; Lembo, Francesca

2017-01-01

Alterations of microbiota-gut-brain axis have been invoked in the pathogenesis of autism spectrum disorders (ASD). Mouse models could represent an excellent tool to understand how gut dysbiosis and related alterations may contribute to autistic phenotype. In this study we paralleled gut microbiota (GM) profiles, behavioral characteristics, intestinal integrity and immunological features of colon tissues in BTBR T + tf/J (BTBR) inbred mice, a well established animal model of ASD. Sex differences, up to date poorly investigated in animal models, were specifically addressed. Results showed that BTBR mice of both sexes presented a marked intestinal dysbiosis, alterations of behavior, gut permeability and immunological state with respect to prosocial C57BL/6j (C57) strain. Noticeably, sex-related differences were clearly detected. We identified Bacteroides, Parabacteroides, Sutterella, Dehalobacterium and Oscillospira genera as key drivers of sex-specific gut microbiota profiles associated with selected pathological traits. Taken together, our findings indicate that alteration of GM in BTBR mice shows relevant sex-associated differences and supports the use of BTBR mouse model to dissect autism associated microbiota-gut-brain axis alteration. PMID:28349974

Sex-Role Ideology and the Aspirations of High School Girls

ERIC Educational Resources Information Center

Gaskell, Jane

1977-01-01

Variables specifically related to sex-role definitions in our society must be considered in accounting for the generally lower aspirations of women since after controlling the variables of social class and academic achievement, sex continues to make a difference in the aspiration levels of high school girls. (MJB)

Sex Role Orientation Across the Adult Life Span.

ERIC Educational Resources Information Center

Zaks, Peggy M.; And Others

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

Species- and sex-specific connectivity effects of habitat fragmentation in a suite of woodland birds.

PubMed

Amos, Nevil; Harrisson, Katherine A; Radford, James Q; White, Matt; Newell, Graeme; Mac Nally, Ralph; Sunnucks, Paul; Pavlova, Alexandra

2014-06-01

Loss of functional connectivity following habitat loss and fragmentation could drive species declines. A comprehensive understanding of fragmentation effects on functional connectivity of an ecological assemblage requires investigation of multiple species with different mobilities, at different spatial scales, for each sex, and in different landscapes. Based on published data on mobility and ecological responses to fragmentation of 10 woodland-dependent birds, and using simulation studies, we predicted that (1) fragmentation would impede dispersal and gene flow of eight "decliners" (species that disappear from suitable patches when landscape-level tree cover falls below species-specific thresholds), but not of two "tolerant" species (whose occurrence in suitable habitat patches is independent of landscape tree cover); and that fragmentation effects would be stronger (2) in the least mobile species, (3) in the more philopatric sex, and (4) in the more fragmented region. We tested these predictions by evaluating spatially explicit isolation-by-landscape-resistance models of gene flow in fragmented landscapes across a 50 x 170 km study area in central Victoria, Australia, using individual and population genetic distances. To account for sex-biased dispersal and potential scale- and configuration-specific effects, we fitted models specific to sex and geographic zones. As predicted, four of the least mobile decliners showed evidence of reduced genetic connectivity. The responses were strongly sex specific, but in opposite directions in the two most sedentary species. Both tolerant species and (unexpectedly) four of the more mobile decliners showed no reduction in gene flow. This is unlikely to be due to time lags because more mobile species develop genetic signatures of fragmentation faster than do less mobile ones. Weaker genetic effects were observed in the geographic zone with more aggregated vegetation, consistent with gene flow being unimpeded by landscape structure. Our results indicate that for all but the most sedentary species in our system, the movement of the more dispersive sex (females in most cases) maintains overall genetic connectivity across fragmented landscapes in the study area, despite some small-scale effects on the more philopatric sex for some species. Nevertheless, to improve population viability for the less mobile bird species, structural landscape connectivity must be increased.

Distinctive roles of age, sex, and genetics in shaping transcriptional variation of human immune responses to microbial challenges.

PubMed

Piasecka, Barbara; Duffy, Darragh; Urrutia, Alejandra; Quach, Hélène; Patin, Etienne; Posseme, Céline; Bergstedt, Jacob; Charbit, Bruno; Rouilly, Vincent; MacPherson, Cameron R; Hasan, Milena; Albaud, Benoit; Gentien, David; Fellay, Jacques; Albert, Matthew L; Quintana-Murci, Lluis

2018-01-16

The contribution of host genetic and nongenetic factors to immunological differences in humans remains largely undefined. Here, we generated bacterial-, fungal-, and viral-induced immune transcriptional profiles in an age- and sex-balanced cohort of 1,000 healthy individuals and searched for the determinants of immune response variation. We found that age and sex affected the transcriptional response of most immune-related genes, with age effects being more stimulus-specific relative to sex effects, which were largely shared across conditions. Although specific cell populations mediated the effects of age and sex on gene expression, including CD8 + T cells for age and CD4 + T cells and monocytes for sex, we detected a direct effect of these intrinsic factors for the majority of immune genes. The mapping of expression quantitative trait loci (eQTLs) revealed that genetic factors had a stronger effect on immune gene regulation than age and sex, yet they affected a smaller number of genes. Importantly, we identified numerous genetic variants that manifested their regulatory effects exclusively on immune stimulation, including a Candida albicans -specific master regulator at the CR1 locus. These response eQTLs were enriched in disease-associated variants, particularly for autoimmune and inflammatory disorders, indicating that differences in disease risk may result from regulatory variants exerting their effects only in the presence of immune stress. Together, this study quantifies the respective effects of age, sex, genetics, and cellular heterogeneity on the interindividual variability of immune responses and constitutes a valuable resource for further exploration in the context of different infection risks or disease outcomes. Copyright © 2018 the Author(s). Published by PNAS.

Stroke and myocardial infarction: a comparative systematic evaluation of gender-specific analysis, funding and authorship patterns in cardiovascular research.

PubMed

Oertelt-Prigione, Sabine; Wiedmann, Silke; Endres, Matthias; Nolte, Christian H; Regitz-Zagrosek, Vera; Heuschmann, Peter

2011-01-01

Major gender differences exist in cardiovascular diseases and lead to different outcomes in women and men. However, attention and incorporation of sex-/gender-specific research might vary among disciplines. We therefore conducted a systematic review comparing publication characteristics and trends between stroke and myocardial infarction (MI) with respect to sex- and gender-related aspects. A systematic literature search was performed in PubMed to identify gender-/sex-related articles published for stroke and MI between 1977 and 2008. A specifically designed text mining program was used, and all literature was rated by two independent investigators. Publications were classified according to type of research performed, publication year, funding, geographical location, and gender of first and last authors. 962 articles were retrieved and limited to 405 (42%) gender-relevant publications; 131 on stroke and 274 on MI. Type of performed research differed, especially in disease management, which received little attention (17%) in stroke, while representing the major focus in MI (40%). In both areas, clinical presentation received little attention (3 and 5%). Although publications progressively increased in both fields, an 8- to 10-year time gap emerged for stroke compared to MI. Last authors in both areas were predominantly men, but female last authorship is increasing more significantly over time in the field of stroke. Research on sex and gender differences in MI and stroke is largely underfunded, particularly by the EU. The data demonstrate how sex-/gender-specific research differs between specialties, most likely due to the diverse interest, funding opportunities and authorship distributions identified. Copyright © 2011 S. Karger AG, Basel.

Comprehensive Characterization of Molecular Differences in Cancer between Male and Female Patients

PubMed Central

Yuan, Yuan; Liu, Lingxiang; Chen, Hu; Wang, Yumeng; Xu, Yanxun; Mao, Huzhang; Li, Jun; Mills, Gordon B.; Shu, Yongqian; Li, Liang; Liang, Han

2016-01-01

Summary An individual’s sex has been long recognized as a key factor affecting cancer incidence, prognosis and treatment responses. However, the molecular basis for sex disparities in cancer remains poorly understood. We performed a comprehensive analysis of molecular differences between male and female patients in 13 cancer types of The Cancer Genome Atlas and revealed two sex-effect groups associated with distinct incidence and mortality profiles. One group contains a small number of sex-affected genes, whereas the other shows much more extensive sex-biased molecular signatures. Importantly, 53% of clinically actionable genes (60/114) show sex-biased signatures. Our study provides a systematic molecular-level understanding of sex effects in diverse cancers and suggests a pressing need to develop sex-specific therapeutic strategies in certain cancer types. PMID:27165743

Differences in the thermal physiology of adult Yarrow's spiny lizards (Sceloporus jarrovii) in relation to sex and body size.

PubMed

Beal, Martin S; Lattanzio, Matthew S; Miles, Donald B

2014-11-01

Sexual size dimorphism (SSD) is often assumed to reflect the phenotypic consequences of differential selection operating on each sex. Species that exhibit SSD may also show intersexual differences in other traits, including field-active body temperatures, preferred temperatures, and locomotor performance. For these traits, differences may be correlated with differences in body size or reflect sex-specific trait optima. Male and female Yarrow's spiny lizards, Sceloporus jarrovii, in a population in southeastern Arizona exhibit a difference in body temperature that is unrelated to variation in body size. The observed sexual variation in body temperature may reflect divergence in thermal physiology between the sexes. To test this hypothesis, we measured the preferred body temperatures of male and female lizards when recently fed and fasted. We also estimated the thermal sensitivity of stamina at seven body temperatures. Variation in these traits provided an opportunity to determine whether body size or sex-specific variation unrelated to size shaped their thermal physiology. Female lizards, but not males, preferred a lower body temperature when fasted, and this pattern was unrelated to body size. Larger individuals exhibited greater stamina, but we detected no significant effect of sex on the shape or height of the thermal performance curves. The thermal preference of males and females in a thermal gradient exceeded the optimal temperature for performance in both sexes. Our findings suggest that differences in thermal physiology are both sex- and size-based and that peak performance at low body temperatures may be adaptive given the reproductive cycles of this viviparous species. We consider the implications of our findings for the persistence of S. jarrovii and other montane ectotherms in the face of climate warming.

Differences in the thermal physiology of adult Yarrow's spiny lizards (Sceloporus jarrovii) in relation to sex and body size

PubMed Central

Beal, Martin S; Lattanzio, Matthew S; Miles, Donald B

2014-01-01

Sexual size dimorphism (SSD) is often assumed to reflect the phenotypic consequences of differential selection operating on each sex. Species that exhibit SSD may also show intersexual differences in other traits, including field-active body temperatures, preferred temperatures, and locomotor performance. For these traits, differences may be correlated with differences in body size or reflect sex-specific trait optima. Male and female Yarrow's spiny lizards, Sceloporus jarrovii, in a population in southeastern Arizona exhibit a difference in body temperature that is unrelated to variation in body size. The observed sexual variation in body temperature may reflect divergence in thermal physiology between the sexes. To test this hypothesis, we measured the preferred body temperatures of male and female lizards when recently fed and fasted. We also estimated the thermal sensitivity of stamina at seven body temperatures. Variation in these traits provided an opportunity to determine whether body size or sex-specific variation unrelated to size shaped their thermal physiology. Female lizards, but not males, preferred a lower body temperature when fasted, and this pattern was unrelated to body size. Larger individuals exhibited greater stamina, but we detected no significant effect of sex on the shape or height of the thermal performance curves. The thermal preference of males and females in a thermal gradient exceeded the optimal temperature for performance in both sexes. Our findings suggest that differences in thermal physiology are both sex- and size-based and that peak performance at low body temperatures may be adaptive given the reproductive cycles of this viviparous species. We consider the implications of our findings for the persistence of S. jarrovii and other montane ectotherms in the face of climate warming. PMID:25540684

Evolving doublesex expression correlates with the origin and diversification of male sexual ornaments in the Drosophila immigrans species group.

PubMed

Rice, Gavin; Barmina, Olga; Hu, Kevin; Kopp, Artyom

2018-03-01

Male ornaments and other sex-specific traits present some of the most dramatic examples of evolutionary innovations. Comparative studies of similar but independently evolved traits are particularly important for identifying repeated patterns in the evolution of these traits. Male-specific modifications of the front legs have evolved repeatedly in Drosophilidae and other Diptera. The best understood of these novel structures is the sex comb of Drosophila melanogaster and its close relatives. Here, we examine the evolution of another male foreleg modification, the sex brush, found in the distantly related Drosophila immigrans species group. Similar to the sex comb, we find that the origin of the sex brush correlates with novel, spatially restricted expression of the doublesex (dsx) transcription factor, the primary effector of the Drosophila sex determination pathway. The diversity of Dsx expression patterns in the immigrans species group closely reflects the differences in the presence, position, and size of the sex brush. Together with previous work on sex comb evolution, these observations suggest that tissue-specific activation of dsx expression may be a common mechanism responsible for the evolution of sexual dimorphism and particularly for the origin of novel male-specific ornaments. © 2018 Wiley Periodicals, Inc.

Sex disparities in cancer incidence in Jiashan County, China, 1995-2014.

PubMed

Jiang, Xiyi; Cai, Shaofang; Hu, Yunqing; Ye, Ding; Li, Qilong; Chen, Kun; Jin, Mingjuan

2017-10-01

To describe the sex-specific incidence rates and the male-to-female incidence-rate ratios (IRRs) of different cancer types, and to explore the corresponding sex disparities in an area of Eastern China. We used data from the Cancer Registry in Jiashan County, and calculated the sex-specific age-standardized (2010 China standard population) incidence rates and the male-to-female IRRs for different cancer types during the period 1995-2014. The age-standardized incidence rates of all cancers for the whole period 1995-2014 were 151.48 per 100,000 person-years for males and 83.75 per 100,000 person-years for females, and the corresponding male-to-female IRR was 1.81 (95% confidence interval: 1.77-1.85). Specifically, males presented higher incidences in most types of cancer with the exceptions of cancers of connective and other soft tissues, gallbladder (including extrahepatic bile ducts), and thyroid gland. In addition, the age-specific incidences of the ten most common cancers in males were higher than those in females in most age groups. Our results reveal a male predominance in incidence for a majority of cancers in Jiashan County, Eastern China. Possible explanations for these sex disparities in cancer incidence may include lifestyle factors, particularly smoking. Copyright © 2017. Published by Elsevier Ltd.

Sex-specific effects of protein and carbohydrate intake on reproduction but not lifespan in Drosophila melanogaster

PubMed Central

Jensen, Kim; McClure, Colin; Priest, Nicholas K; Hunt, John

2015-01-01

Modest dietary restriction extends lifespan (LS) in a diverse range of taxa and typically has a larger effect in females than males. Traditionally, this has been attributed to a stronger trade-off between LS and reproduction in females than in males that is mediated by the intake of calories. Recent studies, however, suggest that it is the intake of specific nutrients that extends LS and mediates this trade-off. Here, we used the geometric framework (GF) to examine the sex-specific effects of protein (P) and carbohydrate (C) intake on LS and reproduction in Drosophila melanogaster. We found that LS was maximized at a high intake of C and a low intake of P in both sexes, whereas nutrient intake had divergent effects on reproduction. Male offspring production rate and LS were maximized at the same intake of nutrients, whereas female egg production rate was maximized at a high intake of diets with a P:C ratio of 1:2. This resulted in larger differences in nutrient-dependent optima for LS and reproduction in females than in males, as well as an optimal intake of nutrients for lifetime reproduction that differed between the sexes. Under dietary choice, the sexes followed similar feeding trajectories regulated around a P:C ratio of 1:4. Consequently, neither sex reached their nutritional optimum for lifetime reproduction, suggesting intralocus sexual conflict over nutrient optimization. Our study shows clear sex differences in the nutritional requirements of reproduction in D. melanogaster and joins the growing list of studies challenging the role of caloric restriction in extending LS. PMID:25808180

Functional Specificity and Sex Differences in the Neural Circuits Supporting the Inhibition of Automatic Imitation.

PubMed

Darda, Kohinoor M; Butler, Emily E; Ramsey, Richard

2018-06-01

Humans show an involuntary tendency to copy other people's actions. Although automatic imitation builds rapport and affiliation between individuals, we do not copy actions indiscriminately. Instead, copying behaviors are guided by a selection mechanism, which inhibits some actions and prioritizes others. To date, the neural underpinnings of the inhibition of automatic imitation and differences between the sexes in imitation control are not well understood. Previous studies involved small sample sizes and low statistical power, which produced mixed findings regarding the involvement of domain-general and domain-specific neural architectures. Here, we used data from Experiment 1 ( N = 28) to perform a power analysis to determine the sample size required for Experiment 2 ( N = 50; 80% power). Using independent functional localizers and an analysis pipeline that bolsters sensitivity, during imitation control we show clear engagement of the multiple-demand network (domain-general), but no sensitivity in the theory-of-mind network (domain-specific). Weaker effects were observed with regard to sex differences, suggesting that there are more similarities than differences between the sexes in terms of the neural systems engaged during imitation control. In summary, neurocognitive models of imitation require revision to reflect that the inhibition of imitation relies to a greater extent on a domain-general selection system rather than a domain-specific system that supports social cognition.

Female cats, but not males, adjust responsiveness to arousal in the voice of kittens.

PubMed

Konerding, Wiebke S; Zimmermann, Elke; Bleich, Eva; Hedrich, Hans-Jürgen; Scheumann, Marina

2016-08-12

The infant cry is the most important communicative tool to elicit adaptive parental behaviour. Sex-specific adaptation, linked to parental investment, may have evolutionary shaped the responsiveness to changes in the voice of the infant cries. The emotional content of infant cries may trigger distinctive responsiveness either based on their general arousing properties, being part of a general affect encoding rule, or based on affective perception, linked to parental investment, differing between species. To address this question, we performed playback experiments using infant isolation calls in a species without paternal care, the domestic cat. We used kitten calls recorded in isolation contexts inducing either Low arousal (i.e., isolation only) or High arousal (i.e., additional handling), leading to respective differences in escape response of the kittens. We predicted that only females respond differently to playbacks of Low versus High arousal kitten isolation calls, based on sex-differences in parental investment. Findings showed sex-specific responsiveness of adult cats listening to kitten isolation calls of different arousal conditions, with only females responding faster towards calls of the High versus the Low arousal condition. Breeding experience of females did not affect the result. Furthermore, female responsiveness correlated with acoustic parameters related to spectral characteristics of the fundamental frequency (F0): Females responded faster to kitten calls with lower F0 at call onset, lower minimum F0 and a steeper slope of the F0. Our study revealed sex-specific differences in the responsiveness to kitten isolation calls of different arousal conditions independent of female breeding experience. The findings indicated that features of F0 are important to convey the arousal state of an infant. Taken together, the results suggest that differences in parental investment evolutionary shaped responsiveness (auditory sensitivity/ motivation) to infant calls in a sex-specific manner in the domestic cat.

Gender differences in chemical carcinogenesis in National Toxicology Program two-year bioassays

PubMed Central

Kadekar, Sandeep; Peddada, Shyamal; Silins, Ilona; French, John E; Högberg, Johan; Stenius, Ulla

2016-01-01

Differences in cancer incidences between men and women are often explained by either differences in environmental exposures or by influences of sex hormones. However, there are few studies on intrinsic gender differences in susceptibility to chemical carcinogens. We have analyzed the National Toxicology Program (NTP) database for sex differences in rat responses to chemical carcinogens. We find that the odds that male rat bioassays were assigned a higher level of evidence than female rat bioassays was 1.69 (p<0.001). Of 278 carcinogenic chemicals in the database, 201 (72%) exhibited statistical gender differences (p = 0.05) in at least one non-reproductive organ. 130 of these 201 chemicals induced gender-specific tumors in male rats and 59 in female rats. 68 chemicals induced tumors in males but no tumors in females. Less than one third, i.e. 19 chemicals, induced tumors in females but not males. Male-specific tumors included pancreatic tumor and skin tumor, and female-specific tumors included lung tumors. For some tumor types these differences in gender susceptibility can be associated with literature data on sex hormone receptor expression. In conclusion, gender-specific tumors were common. The male dominance is in line with human data and the male susceptibility to carcinogens should be further studied. PMID:22585941

Sex-stratified genome-wide association studies including 270,000 individuals show sexual dimorphism in genetic loci for anthropometric traits.

PubMed

Randall, Joshua C; Winkler, Thomas W; Kutalik, Zoltán; Berndt, Sonja I; Jackson, Anne U; Monda, Keri L; Kilpeläinen, Tuomas O; Esko, Tõnu; Mägi, Reedik; Li, Shengxu; Workalemahu, Tsegaselassie; Feitosa, Mary F; Croteau-Chonka, Damien C; Day, Felix R; Fall, Tove; Ferreira, Teresa; Gustafsson, Stefan; Locke, Adam E; Mathieson, Iain; Scherag, Andre; Vedantam, Sailaja; Wood, Andrew R; Liang, Liming; Steinthorsdottir, Valgerdur; Thorleifsson, Gudmar; Dermitzakis, Emmanouil T; Dimas, Antigone S; Karpe, Fredrik; Min, Josine L; Nicholson, George; Clegg, Deborah J; Person, Thomas; Krohn, Jon P; Bauer, Sabrina; Buechler, Christa; Eisinger, Kristina; Bonnefond, Amélie; Froguel, Philippe; Hottenga, Jouke-Jan; Prokopenko, Inga; Waite, Lindsay L; Harris, Tamara B; Smith, Albert Vernon; Shuldiner, Alan R; McArdle, Wendy L; Caulfield, Mark J; Munroe, Patricia B; Grönberg, Henrik; Chen, Yii-Der Ida; Li, Guo; Beckmann, Jacques S; Johnson, Toby; Thorsteinsdottir, Unnur; Teder-Laving, Maris; Khaw, Kay-Tee; Wareham, Nicholas J; Zhao, Jing Hua; Amin, Najaf; Oostra, Ben A; Kraja, Aldi T; Province, Michael A; Cupples, L Adrienne; Heard-Costa, Nancy L; Kaprio, Jaakko; Ripatti, Samuli; Surakka, Ida; Collins, Francis S; Saramies, Jouko; Tuomilehto, Jaakko; Jula, Antti; Salomaa, Veikko; Erdmann, Jeanette; Hengstenberg, Christian; Loley, Christina; Schunkert, Heribert; Lamina, Claudia; Wichmann, H Erich; Albrecht, Eva; Gieger, Christian; Hicks, Andrew A; Johansson, Asa; Pramstaller, Peter P; Kathiresan, Sekar; Speliotes, Elizabeth K; Penninx, Brenda; Hartikainen, Anna-Liisa; Jarvelin, Marjo-Riitta; Gyllensten, Ulf; Boomsma, Dorret I; Campbell, Harry; Wilson, James F; Chanock, Stephen J; Farrall, Martin; Goel, Anuj; Medina-Gomez, Carolina; Rivadeneira, Fernando; Estrada, Karol; Uitterlinden, André G; Hofman, Albert; Zillikens, M Carola; den Heijer, Martin; Kiemeney, Lambertus A; Maschio, Andrea; Hall, Per; Tyrer, Jonathan; Teumer, Alexander; Völzke, Henry; Kovacs, Peter; Tönjes, Anke; Mangino, Massimo; Spector, Tim D; Hayward, Caroline; Rudan, Igor; Hall, Alistair S; Samani, Nilesh J; Attwood, Antony Paul; Sambrook, Jennifer G; Hung, Joseph; Palmer, Lyle J; Lokki, Marja-Liisa; Sinisalo, Juha; Boucher, Gabrielle; Huikuri, Heikki; Lorentzon, Mattias; Ohlsson, Claes; Eklund, Niina; Eriksson, Johan G; Barlassina, Cristina; Rivolta, Carlo; Nolte, Ilja M; Snieder, Harold; Van der Klauw, Melanie M; Van Vliet-Ostaptchouk, Jana V; Gejman, Pablo V; Shi, Jianxin; Jacobs, Kevin B; Wang, Zhaoming; Bakker, Stephan J L; Mateo Leach, Irene; Navis, Gerjan; van der Harst, Pim; Martin, Nicholas G; Medland, Sarah E; Montgomery, Grant W; Yang, Jian; Chasman, Daniel I; Ridker, Paul M; Rose, Lynda M; Lehtimäki, Terho; Raitakari, Olli; Absher, Devin; Iribarren, Carlos; Basart, Hanneke; Hovingh, Kees G; Hyppönen, Elina; Power, Chris; Anderson, Denise; Beilby, John P; Hui, Jennie; Jolley, Jennifer; Sager, Hendrik; Bornstein, Stefan R; Schwarz, Peter E H; Kristiansson, Kati; Perola, Markus; Lindström, Jaana; Swift, Amy J; Uusitupa, Matti; Atalay, Mustafa; Lakka, Timo A; Rauramaa, Rainer; Bolton, Jennifer L; Fowkes, Gerry; Fraser, Ross M; Price, Jackie F; Fischer, Krista; Krjutå Kov, Kaarel; Metspalu, Andres; Mihailov, Evelin; Langenberg, Claudia; Luan, Jian'an; Ong, Ken K; Chines, Peter S; Keinanen-Kiukaanniemi, Sirkka M; Saaristo, Timo E; Edkins, Sarah; Franks, Paul W; Hallmans, Göran; Shungin, Dmitry; Morris, Andrew David; Palmer, Colin N A; Erbel, Raimund; Moebus, Susanne; Nöthen, Markus M; Pechlivanis, Sonali; Hveem, Kristian; Narisu, Narisu; Hamsten, Anders; Humphries, Steve E; Strawbridge, Rona J; Tremoli, Elena; Grallert, Harald; Thorand, Barbara; Illig, Thomas; Koenig, Wolfgang; Müller-Nurasyid, Martina; Peters, Annette; Boehm, Bernhard O; Kleber, Marcus E; März, Winfried; Winkelmann, Bernhard R; Kuusisto, Johanna; Laakso, Markku; Arveiler, Dominique; Cesana, Giancarlo; Kuulasmaa, Kari; Virtamo, Jarmo; Yarnell, John W G; Kuh, Diana; Wong, Andrew; Lind, Lars; de Faire, Ulf; Gigante, Bruna; Magnusson, Patrik K E; Pedersen, Nancy L; Dedoussis, George; Dimitriou, Maria; Kolovou, Genovefa; Kanoni, Stavroula; Stirrups, Kathleen; Bonnycastle, Lori L; Njølstad, Inger; Wilsgaard, Tom; Ganna, Andrea; Rehnberg, Emil; Hingorani, Aroon; Kivimaki, Mika; Kumari, Meena; Assimes, Themistocles L; Barroso, Inês; Boehnke, Michael; Borecki, Ingrid B; Deloukas, Panos; Fox, Caroline S; Frayling, Timothy; Groop, Leif C; Haritunians, Talin; Hunter, David; Ingelsson, Erik; Kaplan, Robert; Mohlke, Karen L; O'Connell, Jeffrey R; Schlessinger, David; Strachan, David P; Stefansson, Kari; van Duijn, Cornelia M; Abecasis, Gonçalo R; McCarthy, Mark I; Hirschhorn, Joel N; Qi, Lu; Loos, Ruth J F; Lindgren, Cecilia M; North, Kari E; Heid, Iris M

2013-06-01

Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723 individuals) and took forward 348 SNPs into follow-up (additional 137,052 individuals) in a total of 94 studies. Seven loci displayed significant sex-difference (FDR<5%), including four previously established (near GRB14/COBLL1, LYPLAL1/SLC30A10, VEGFA, ADAMTS9) and three novel anthropometric trait loci (near MAP3K1, HSD17B4, PPARG), all of which were genome-wide significant in women (P<5×10(-8)), but not in men. Sex-differences were apparent only for waist phenotypes, not for height, weight, BMI, or hip circumference. Moreover, we found no evidence for genetic effects with opposite directions in men versus women. The PPARG locus is of specific interest due to its role in diabetes genetics and therapy. Our results demonstrate the value of sex-specific GWAS to unravel the sexually dimorphic genetic underpinning of complex traits.

Sex-stratified Genome-wide Association Studies Including 270,000 Individuals Show Sexual Dimorphism in Genetic Loci for Anthropometric Traits

PubMed Central

Jackson, Anne U.; Monda, Keri L.; Kilpeläinen, Tuomas O.; Esko, Tõnu; Mägi, Reedik; Li, Shengxu; Workalemahu, Tsegaselassie; Feitosa, Mary F.; Croteau-Chonka, Damien C.; Day, Felix R.; Fall, Tove; Ferreira, Teresa; Gustafsson, Stefan; Locke, Adam E.; Mathieson, Iain; Scherag, Andre; Vedantam, Sailaja; Wood, Andrew R.; Liang, Liming; Steinthorsdottir, Valgerdur; Thorleifsson, Gudmar; Dermitzakis, Emmanouil T.; Dimas, Antigone S.; Karpe, Fredrik; Min, Josine L.; Nicholson, George; Clegg, Deborah J.; Person, Thomas; Krohn, Jon P.; Bauer, Sabrina; Buechler, Christa; Eisinger, Kristina; Bonnefond, Amélie; Froguel, Philippe; Hottenga, Jouke-Jan; Prokopenko, Inga; Waite, Lindsay L.; Harris, Tamara B.; Smith, Albert Vernon; Shuldiner, Alan R.; McArdle, Wendy L.; Caulfield, Mark J.; Munroe, Patricia B.; Grönberg, Henrik; Chen, Yii-Der Ida; Li, Guo; Beckmann, Jacques S.; Johnson, Toby; Thorsteinsdottir, Unnur; Teder-Laving, Maris; Khaw, Kay-Tee; Wareham, Nicholas J.; Zhao, Jing Hua; Amin, Najaf; Oostra, Ben A.; Kraja, Aldi T.; Province, Michael A.; Cupples, L. Adrienne; Heard-Costa, Nancy L.; Kaprio, Jaakko; Ripatti, Samuli; Surakka, Ida; Collins, Francis S.; Saramies, Jouko; Tuomilehto, Jaakko; Jula, Antti; Salomaa, Veikko; Erdmann, Jeanette; Hengstenberg, Christian; Loley, Christina; Schunkert, Heribert; Lamina, Claudia; Wichmann, H. Erich; Albrecht, Eva; Gieger, Christian; Hicks, Andrew A.; Johansson, Åsa; Pramstaller, Peter P.; Kathiresan, Sekar; Speliotes, Elizabeth K.; Penninx, Brenda; Hartikainen, Anna-Liisa; Jarvelin, Marjo-Riitta; Gyllensten, Ulf; Boomsma, Dorret I.; Campbell, Harry; Wilson, James F.; Chanock, Stephen J.; Farrall, Martin; Goel, Anuj; Medina-Gomez, Carolina; Rivadeneira, Fernando; Estrada, Karol; Uitterlinden, André G.; Hofman, Albert; Zillikens, M. Carola; den Heijer, Martin; Kiemeney, Lambertus A.; Maschio, Andrea; Hall, Per; Tyrer, Jonathan; Teumer, Alexander; Völzke, Henry; Kovacs, Peter; Tönjes, Anke; Mangino, Massimo; Spector, Tim D.; Hayward, Caroline; Rudan, Igor; Hall, Alistair S.; Samani, Nilesh J.; Attwood, Antony Paul; Sambrook, Jennifer G.; Hung, Joseph; Palmer, Lyle J.; Lokki, Marja-Liisa; Sinisalo, Juha; Boucher, Gabrielle; Huikuri, Heikki; Lorentzon, Mattias; Ohlsson, Claes; Eklund, Niina; Eriksson, Johan G.; Barlassina, Cristina; Rivolta, Carlo; Nolte, Ilja M.; Snieder, Harold; Van der Klauw, Melanie M.; Van Vliet-Ostaptchouk, Jana V.; Gejman, Pablo V.; Shi, Jianxin; Jacobs, Kevin B.; Wang, Zhaoming; Bakker, Stephan J. L.; Mateo Leach, Irene; Navis, Gerjan; van der Harst, Pim; Martin, Nicholas G.; Medland, Sarah E.; Montgomery, Grant W.; Yang, Jian; Chasman, Daniel I.; Ridker, Paul M.; Rose, Lynda M.; Lehtimäki, Terho; Raitakari, Olli; Absher, Devin; Iribarren, Carlos; Basart, Hanneke; Hovingh, Kees G.; Hyppönen, Elina; Power, Chris; Anderson, Denise; Beilby, John P.; Hui, Jennie; Jolley, Jennifer; Sager, Hendrik; Bornstein, Stefan R.; Schwarz, Peter E. H.; Kristiansson, Kati; Perola, Markus; Lindström, Jaana; Swift, Amy J.; Uusitupa, Matti; Atalay, Mustafa; Lakka, Timo A.; Rauramaa, Rainer; Bolton, Jennifer L.; Fowkes, Gerry; Fraser, Ross M.; Price, Jackie F.; Fischer, Krista; KrjutÅ¡kov, Kaarel; Metspalu, Andres; Mihailov, Evelin; Langenberg, Claudia; Luan, Jian'an; Ong, Ken K.; Chines, Peter S.; Keinanen-Kiukaanniemi, Sirkka M.; Saaristo, Timo E.; Edkins, Sarah; Franks, Paul W.; Hallmans, Göran; Shungin, Dmitry; Morris, Andrew David; Palmer, Colin N. A.; Erbel, Raimund; Moebus, Susanne; Nöthen, Markus M.; Pechlivanis, Sonali; Hveem, Kristian; Narisu, Narisu; Hamsten, Anders; Humphries, Steve E.; Strawbridge, Rona J.; Tremoli, Elena; Grallert, Harald; Thorand, Barbara; Illig, Thomas; Koenig, Wolfgang; Müller-Nurasyid, Martina; Peters, Annette; Boehm, Bernhard O.; Kleber, Marcus E.; März, Winfried; Winkelmann, Bernhard R.; Kuusisto, Johanna; Laakso, Markku; Arveiler, Dominique; Cesana, Giancarlo; Kuulasmaa, Kari; Virtamo, Jarmo; Yarnell, John W. G.; Kuh, Diana; Wong, Andrew; Lind, Lars; de Faire, Ulf; Gigante, Bruna; Magnusson, Patrik K. E.; Pedersen, Nancy L.; Dedoussis, George; Dimitriou, Maria; Kolovou, Genovefa; Kanoni, Stavroula; Stirrups, Kathleen; Bonnycastle, Lori L.; Njølstad, Inger; Wilsgaard, Tom; Ganna, Andrea; Rehnberg, Emil; Hingorani, Aroon; Kivimaki, Mika; Kumari, Meena; Assimes, Themistocles L.; Barroso, Inês; Boehnke, Michael; Borecki, Ingrid B.; Deloukas, Panos; Fox, Caroline S.; Frayling, Timothy; Groop, Leif C.; Haritunians, Talin; Hunter, David; Ingelsson, Erik; Kaplan, Robert; Mohlke, Karen L.; O'Connell, Jeffrey R.; Schlessinger, David; Strachan, David P.; Stefansson, Kari; van Duijn, Cornelia M.; Abecasis, Gonçalo R.; McCarthy, Mark I.; Hirschhorn, Joel N.; Qi, Lu; Loos, Ruth J. F.; Lindgren, Cecilia M.; North, Kari E.; Heid, Iris M.

2013-01-01

Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723 individuals) and took forward 348 SNPs into follow-up (additional 137,052 individuals) in a total of 94 studies. Seven loci displayed significant sex-difference (FDR<5%), including four previously established (near GRB14/COBLL1, LYPLAL1/SLC30A10, VEGFA, ADAMTS9) and three novel anthropometric trait loci (near MAP3K1, HSD17B4, PPARG), all of which were genome-wide significant in women (P<5×10−8), but not in men. Sex-differences were apparent only for waist phenotypes, not for height, weight, BMI, or hip circumference. Moreover, we found no evidence for genetic effects with opposite directions in men versus women. The PPARG locus is of specific interest due to its role in diabetes genetics and therapy. Our results demonstrate the value of sex-specific GWAS to unravel the sexually dimorphic genetic underpinning of complex traits. PMID:23754948

Genetic and epigenetic architecture of sex-biased expression in the jewel wasps Nasonia vitripennis and giraulti

PubMed Central

Wang, Xu; Werren, John H.; Clark, Andrew G.

2015-01-01

There is extraordinary diversity in sexual dimorphism (SD) among animals, but little is known about its epigenetic basis. To study the epigenetic architecture of SD in a haplodiploid system, we performed RNA-seq and whole-genome bisulfite sequencing of adult females and males from two closely related parasitoid wasps, Nasonia vitripennis and Nasonia giraulti. More than 75% of expressed genes displayed significantly sex-biased expression. As a consequence, expression profiles are more similar between species within each sex than between sexes within each species. Furthermore, extremely male- and female-biased genes are enriched for totally different functional categories: male-biased genes for key enzymes in sex-pheromone synthesis and female-biased genes for genes involved in epigenetic regulation of gene expression. Remarkably, just 70 highly expressed, extremely male-biased genes account for 10% of all transcripts in adult males. Unlike expression profiles, DNA methylomes are highly similar between sexes within species, with no consistent sex differences in methylation found. Therefore, methylation changes cannot explain the extensive level of sex-biased gene expression observed. Female-biased genes have smaller sequence divergence between species, higher conservation to other hymenopterans, and a broader expression range across development. Overall, female-biased genes have been recruited from genes with more conserved and broadly expressing “house-keeping” functions, whereas male-biased genes are more recently evolved and are predominately testis specific. In summary, Nasonia accomplish a striking degree of sex-biased expression without sex chromosomes or epigenetic differences in methylation. We propose that methylation provides a general signal for constitutive gene expression, whereas other sex-specific signals cause sex-biased gene expression. PMID:26100871

Sex Differences in Reported Pain Across 11,000 Patients Captured in Electronic Medical Records

PubMed Central

Ruau, David; Liu, Linda Y.; Clark, J. David; Angst, Martin S.; Butte, Atul J.

2011-01-01

Clinically recorded pain scores are abundant in patient health records but are rarely used in research. The use of this information could help improve clinical outcomes. For example, a recent report by the Institute of Medicine stated that ineffective use of clinical information contributes to under-treatment of patient subpopulations — especially women. This study used diagnosis-associated pain scores from a large hospital database to document sex differences in reported pain. We used de-identified electronic medical records from Stanford Hospital and Clinics for more than 72,000 patients. Each record contained at least one disease-associated pain score. We found over 160,000 pain scores in more than 250 primary diagnoses, and analyzed differences in disease-specific pain reported by men and women. After filtering for diagnoses with minimum encounter numbers, we found diagnosis-specific sex differences in reported pain. The most significant differences occurred in patients with disorders of the musculoskeletal, circulatory, respiratory and digestive systems, followed by infectious diseases, and injury and poisoning. We also discovered sex-specific differences in pain intensity in previously unreported diseases, including disorders of the cervical region, and acute sinusitis (p = 0.01, 0.017, respectively). Pain scores were collected during hospital encounters. No information about the use of pre-encounter over-the-counter medications was available. To our knowledge, this is the largest data-driven study documenting sex differences of disease-associated pain. It highlights the utility of EMR data to corroborate and expand on results of smaller clinical studies. Our findings emphasize the need for future research examining the mechanisms underlying differences in pain. PMID:22245360

Sex differences in disease-specific health status measures in patients with symptomatic peripheral artery disease: Data from the PORTRAIT study.

PubMed

Roumia, Mazen; Aronow, Herbert D; Soukas, Peter; Gosch, Kensey; Smolderen, Kim G; Spertus, John A; Abbott, J Dawn

2017-04-01

Peripheral artery disease (PAD) is associated with poor health status (symptoms, functioning, quality of life (QOL)). Whether sex differences exist in PAD-specific health status is unknown. In patients presenting to a specialty clinic with new-onset or recent exacerbation of PAD, we examined sex differences as assessed by the Peripheral Artery Questionnaire (PAQ). The Patient-centered Outcomes Related to TReatment Practices in Peripheral Arterial Disease: Investigating Trajectories (PORTRAIT) study is a multicenter, international prospective study of patients with new or worsening PAD symptoms. Baseline characteristics and mean PAQ scores were compared among women ( n=481) and men ( n=793) before they underwent treatment. The independent association of sex with health status was assessed with multivariable linear regression. As compared with men, women were less often Caucasian, married and employed, and more often lacking health insurance, living alone (36.2% vs 23.6%, p<0.001), had depression and avoided care due to cost (17.0% vs 12.3%, p=0.018). Women and men were of a similar age and education level, and had similar ankle-brachial index (ABI) values (0.7 ± 0.2 in both groups, p=0.052). Female sex was independently associated with lower PAQ scores on all domains (physical functioning adjusted mean difference of -8.40, p<0.001; social functioning adjusted mean difference of -6.8, p<0.001; QOL adjusted mean difference of -6.7, p<0.001), although no differences were observed in treatment satisfaction (adjusted mean difference -0.20, p=0.904). Despite similar ABIs, women presenting with symptoms of PAD had poorer PAD-specific functioning as compared with men, impacting all major health status domains, independent of socio-economic and clinical characteristics.

Sex-specific genetic architecture of human fatness in Chinese: the SAPPHIRe Study.

PubMed

Chiu, Y-F; Chuang, L-M; Kao, H-Y; Shih, K-C; Lin, M-W; Lee, W-J; Quertermous, T; Curb, J D; Chen, I; Rodriguez, B L; Hsiung, C A

2010-11-01

To dissect the genetic architecture of sexual dimorphism in obesity-related traits, we evaluated the sex-genotype interaction, sex-specific heritability and genome-wide linkages for seven measurements related to obesity. A total of 1,365 non-diabetic Chinese subjects from the family study of the Stanford Asia-Pacific Program of Hypertension and Insulin Resistance were used to search for quantitative trait loci (QTLs) responsible for the obesity-related traits. Pleiotropy and co-incidence effects from the QTLs were also examined using the bivariate linkage approach. We found that sex-specific differences in heritability and the genotype-sex interaction effects were substantially significant for most of these traits. Several QTLs with strong linkage evidence were identified after incorporating genotype by sex (G × S) interactions into the linkage mapping, including one QTL for hip circumference [maximum LOD score (MLS) = 4.22, empirical p = 0.000033] and two QTLs: for BMI on chromosome 12q with MLS 3.37 (empirical p = 0.0043) and 3.10 (empirical p = 0.0054). Sex-specific analyses demonstrated that these linkage signals all resulted from females rather than males. Most of these QTLs for obesity-related traits replicated the findings in other ethnic groups. Bivariate linkage analyses showed several obesity traits were influenced by a common set of QTLs. All regions with linkage signals were observed in one gender, but not in the whole sample, suggesting the genetic architecture of obesity-related traits does differ by gender. These findings are useful for further identification of the liability genes for these phenotypes through candidate genes or genome-wide association analysis.

The impact of sex as a biological variable in the search for novel antidepressants.

PubMed

Williams, Alexia V; Trainor, Brian C

2018-05-31

A roadblock to successful treatment for anxiety and depression is the high proportion of individuals that do not respond to existing treatments. Different underlying neurobiological mechanisms may drive similar symptoms, so a more personalized approach to treatment could be more successful. There is increasing evidence that sex is an important biological variable modulating efficacy of antidepressants and anxiolytics. We review evidence for sex-specific effects of traditional monoamine based antidepressants and newer pharmaceuticals targeting kappa opioid receptors (KOR), oxytocin receptors (OTR), and N-methyl-D-aspartate receptors (ketamine). In some cases, similar behavioral effects are observed in both sexes while in other cases strong sex-specific effects are observed. Most intriguing are cases such as ketamine which has similar behavioral effects in males and females, perhaps through sex-specific neurobiological mechanisms. These results show how essential it is to include both males and females in both clinical and preclinical evaluations of novel antidepressants and anxiolytics. Copyright © 2018 Elsevier Inc. All rights reserved.

Sex-specific reaction norms to intraspecific larval competition in the mosquito Aedes aegypti.

PubMed

Bedhomme, S; Agnew, P; Sidobre, C; Michalakis, Y

2003-07-01

As the relationship between a given life-history trait and fitness is not necessarily the same for the two sexes, an 'intersexual ontogenetic conflict' may arise. We analysed the phenotypic reaction to intraspecific larval competition of the mosquito, Aedes aegypti, asking: (i) Do both sexes pay the cost of competition with the same life-history traits and are they equal competitors? (ii) Is there a specific cost of competition beyond sharing food resources? We found that competition incurs a specific cost that was expressed differently by the two sexes. Indeed, each sex maintained the more important life-history trait(s) for their fitness (developmental time for males and body weight and size for females) at the expense of other traits, thus minimizing the effects of competition on their fitness. The competition exerted by females was estimated as being more intense, probably linked with the greater importance of body size for their fitness.

Heavy Episodic Drinking and Alcohol-Related Consequences: Sex-Specific Differences in Parental Influences among Ninth-Grade Students

ERIC Educational Resources Information Center

Doumas, Diana M.; Hausheer, Robin; Esp, Susan

2015-01-01

Parents impact adolescent substance abuse, but sex-specific influences are not well-understood. This study examined parental influences on adolescent drinking behavior in a sample of ninth-grade students (N = 473). Hierarchical regression analyses indicated parental monitoring, disapproval of teen alcohol use, and quality of parent-teen general…

Activation patterns of vasopressinergic and oxytocinergic brain regions following social play exposure in juvenile male and female rats.

PubMed

Reppucci, C J; Gergely, C K; Veenema, A H

2018-02-09

Social play is a highly rewarding and motivated behavior predominately displayed by juveniles and expressed by nearly all mammalian species. Prior work suggested that the vasopressin (AVP) and oxytocin (OT) systems can regulate the expression of social play in sex-specific ways. Here we investigated whether there are sex differences in the recruitment of vasopressinergic and oxytocinergic brain regions following social play exposure in juvenile rats. Single-housed rats were allowed to play, in their home cage, with an age- and sex-matched unfamiliar conspecific for 10 min, or received similar handling but no partner. Double-labeled fluorescent immunohistochemistry for Fos and either AVP or OT was completed in adjacent series of tissue to determine recruitment of AVP- and OT-immunoreactive neurons in response to social play. Exposure to social play did not increase recruitment of AVP or OT neurons in the supraoptic (SO) or paraventricular (PVH) hypothalamic nuclei of either sex compared to the no-play control condition. Interestingly, there was a robust sex difference in SO recruitment, irrespective of social play condition, with males exhibiting twice the recruitment of SO-AVP and SO-OT neurons compared to females. Lastly, exposure to social play increased recruitment of the posterior bed nuclei of the stria terminalis (pBST) and the posterodorsal medial amygdalar nucleus (MEApd) compared to the no-play control condition, and this effect was most pronounced in females. Our findings revealed sex differences in the recruitment of brain regions (i) independent of play condition (i.e., SO) possibly representing a sex difference in the baseline levels of AVP and OT signaling required for typical functioning and (ii) specific to play condition (i.e., pBST, MEApd). In sum, this study provides further evidence that the neural substrates underlying social play behavior are sex-specific. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Digital transcriptome analysis of putative sex-determination genes in papaya (Carica papaya).

PubMed

Urasaki, Naoya; Tarora, Kazuhiko; Shudo, Ayano; Ueno, Hiroki; Tamaki, Moritoshi; Miyagi, Norimichi; Adaniya, Shinichi; Matsumura, Hideo

2012-01-01

Papaya (Carica papaya) is a trioecious plant species that has male, female and hermaphrodite flowers on different plants. The primitive sex chromosomes genetically determine the sex of the papaya. Although draft sequences of the papaya genome are already available, the genes for sex determination have not been identified, likely due to the complicated structure of its sex-chromosome sequences. To identify the candidate genes for sex determination, we conducted a transcriptome analysis of flower samples from male, female and hermaphrodite plants using high-throughput SuperSAGE for digital gene expression analysis. Among the short sequence tags obtained from the transcripts, 312 unique tags were specifically mapped to the primitive sex chromosome (X or Y(h)) sequences. An annotation analysis revealed that retroelements are the most abundant sequences observed in the genes corresponding to these tags. The majority of tags on the sex chromosomes were located on the X chromosome, and only 30 tags were commonly mapped to both the X and Y(h) chromosome, implying a loss of many genes on the Y(h) chromosome. Nevertheless, candidate Y(h) chromosome-specific female determination genes, including a MADS-box gene, were identified. Information on these sex chromosome-specific expressed genes will help elucidating sex determination in the papaya.

Digital Transcriptome Analysis of Putative Sex-Determination Genes in Papaya (Carica papaya)

PubMed Central

Urasaki, Naoya; Tarora, Kazuhiko; Shudo, Ayano; Ueno, Hiroki; Tamaki, Moritoshi; Miyagi, Norimichi; Adaniya, Shinichi; Matsumura, Hideo

2012-01-01

Papaya (Carica papaya) is a trioecious plant species that has male, female and hermaphrodite flowers on different plants. The primitive sex chromosomes genetically determine the sex of the papaya. Although draft sequences of the papaya genome are already available, the genes for sex determination have not been identified, likely due to the complicated structure of its sex-chromosome sequences. To identify the candidate genes for sex determination, we conducted a transcriptome analysis of flower samples from male, female and hermaphrodite plants using high-throughput SuperSAGE for digital gene expression analysis. Among the short sequence tags obtained from the transcripts, 312 unique tags were specifically mapped to the primitive sex chromosome (X or Yh) sequences. An annotation analysis revealed that retroelements are the most abundant sequences observed in the genes corresponding to these tags. The majority of tags on the sex chromosomes were located on the X chromosome, and only 30 tags were commonly mapped to both the X and Yh chromosome, implying a loss of many genes on the Yh chromosome. Nevertheless, candidate Yh chromosome-specific female determination genes, including a MADS-box gene, were identified. Information on these sex chromosome-specific expressed genes will help elucidating sex determination in the papaya. PMID:22815863

Sex differences in brain activation to emotional stimuli: a meta-analysis of neuroimaging studies.

PubMed

Stevens, Jennifer S; Hamann, Stephan

2012-06-01

Substantial sex differences in emotional responses and perception have been reported in previous psychological and psychophysiological studies. For example, women have been found to respond more strongly to negative emotional stimuli, a sex difference that has been linked to an increased risk of depression and anxiety disorders. The extent to which such sex differences are reflected in corresponding differences in regional brain activation remains a largely unresolved issue, however, in part because relatively few neuroimaging studies have addressed this issue. Here, by conducting a quantitative meta-analysis of neuroimaging studies, we were able to substantially increase statistical power to detect sex differences relative to prior studies, by combining emotion studies which explicitly examined sex differences with the much larger number of studies that examined only women or men. We used an activation likelihood estimation approach to characterize sex differences in the likelihood of regional brain activation elicited by emotional stimuli relative to non-emotional stimuli. We examined sex differences separately for negative and positive emotions, in addition to examining all emotions combined. Sex differences varied markedly between negative and positive emotion studies. The majority of sex differences favoring women were observed for negative emotion, whereas the majority of the sex differences favoring men were observed for positive emotion. This valence-specificity was particularly evident for the amygdala. For negative emotion, women exhibited greater activation than men in the left amygdala, as well as in other regions including the left thalamus, hypothalamus, mammillary bodies, left caudate, and medial prefrontal cortex. In contrast, for positive emotion, men exhibited greater activation than women in the left amygdala, as well as greater activation in other regions including the bilateral inferior frontal gyrus and right fusiform gyrus. These meta-analysis findings indicate that the amygdala, a key region for emotion processing, exhibits valence-dependent sex differences in activation to emotional stimuli. The greater left amygdala response to negative emotion for women accords with previous reports that women respond more strongly to negative emotional stimuli, as well as with hypothesized links between increased neurobiological reactivity to negative emotion and increased prevalence of depression and anxiety disorders in women. The finding of greater left amygdala activation for positive emotional stimuli in men suggests that greater amygdala responses reported previously for men for specific types of positive stimuli may also extend to positive stimuli more generally. In summary, this study extends efforts to characterize sex differences in brain activation during emotion processing by providing the largest and most comprehensive quantitative meta-analysis to date, and for the first time examining sex differences as a function of positive vs. negative emotional valence. The current findings highlight the importance of considering sex as a potential factor modulating emotional processing and its underlying neural mechanisms, and more broadly, the need to consider individual differences in understanding the neurobiology of emotion. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

Hecking, Manfred; Bieber, Brian A.; Ethier, Jean; Kautzky-Willer, Alexandra; Sunder-Plassmann, Gere; Säemann, Marcus D.; Ramirez, Sylvia P. B.; Gillespie, Brenda W.; Pisoni, Ronald L.; Robinson, Bruce M.; Port, Friedrich K.

2014-01-01

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

A specific sexual orientation-related difference in navigation strategy.

PubMed

Rahman, Qazi; Andersson, Davinia; Govier, Ernest

2005-02-01

During spatial navigation, women typically navigate an environment using a landmark strategy, whereas men typically use an orientation strategy. To examine the as yet unknown effects of sexual orientation on these normative sex differences, this study required 80 healthy heterosexual and homosexual adult men and women to provide directions from experimental maps for 4 routes. The frequency and type of strategy used by each participant were computed. Expected sex differences were demonstrated, and a robust cross-sex shift was shown by homosexual men in using landmarks. This remained after controlling for differences in mental rotation, directional sense, and general intelligence. The findings may limit the number of putative neurodevelopmental pathways responsible for sex differences in navigation strategy utility. Copyright 2005 APA.

Gestational Dietary Protein Is Associated with Sex Specific Decrease in Blood Flow, Fetal Heart Growth and Post-Natal Blood Pressure of Progeny

PubMed Central

2015-01-01

Study Overview The incidence of adverse pregnancy outcomes is higher in pregnancies where the fetus is male. Sex specific differences in feto-placental perfusion indices identified by Doppler assessment have recently been associated with placental insufficiency and fetal growth restriction. This study aims to investigate sex specific differences in placental perfusion and to correlate these changes with fetal growth. It represents the largest comprehensive study under field conditions of uterine hemodynamics in a monotocous species, with a similar long gestation period to the human. Primiparous 14mo heifers in Australia (n=360) and UK (n=180) were either individually or group fed, respectively, diets with differing protein content (18, 14, 10 or 7% crude protein (CP)) from 60d prior to 98 days post conception (dpc). Fetuses and placentae were excised at 98dpc (n = 48). Fetal development an median uterine artery blood flow were assessed monthly from 36dpc until term using B-mode and Doppler ultrasonography. MUA blood flow to the male feto-placental unit increased in early pregnancy associated with increased fetal growth. Protein restriction before and shortly after conception (-60d up to 23dpc) increased MUA diameter and indices of velocity during late pregnancy, reduced fetal heart weight in the female fetus and increased heart rate at birth, but decreased systolic blood pressure at six months of age. Conclusion and Significance Sex specific differences both in feto-placental Doppler perfusion indices and response of these indices to dietary perturbations were observed. Further, maternal diet affected development of fetal cardiovascular system associated with altered fetal haemodynamics in utero, with such effects having a sex bias. The results from this study provide further insight into the gender specific circulatory differences present in the fetal period and developing cardiovascular system. PMID:25915506

Early sex differences are not autism-specific: A Baby Siblings Research Consortium (BSRC) study.

PubMed

Messinger, Daniel S; Young, Gregory S; Webb, Sara Jane; Ozonoff, Sally; Bryson, Susan E; Carter, Alice; Carver, Leslie; Charman, Tony; Chawarska, Katarzyna; Curtin, Suzanne; Dobkins, Karen; Hertz-Picciotto, Irva; Hutman, Ted; Iverson, Jana M; Landa, Rebecca; Nelson, Charles A; Stone, Wendy L; Tager-Flusberg, Helen; Zwaigenbaum, Lonnie

2015-01-01

The increased male prevalence of autism spectrum disorder (ASD) may be mirrored by the early emergence of sex differences in ASD symptoms and cognitive functioning. The female protective effect hypothesis posits that ASD recurrence and symptoms will be higher among relatives of female probands. This study examined sex differences and sex of proband differences in ASD outcome and in the development of ASD symptoms and cognitive functioning among the high-risk younger siblings of ASD probands and low-risk children. Prior to 18 months of age, 1824 infants (1241 high-risk siblings, 583 low-risk) from 15 sites were recruited. Hierarchical generalized linear model (HGLM) analyses of younger sibling and proband sex differences in ASD recurrence among high-risk siblings were followed by HGLM analyses of sex differences and group differences (high-risk ASD, high-risk non-ASD, and low-risk) on the Mullen Scales of Early Learning (MSEL) subscales (Expressive and Receptive Language, Fine Motor, and Visual Reception) at 18, 24, and 36 months and Autism Diagnostic Observation Schedule (ADOS) domain scores (social affect (SA) and restricted and repetitive behaviors (RRB)) at 24 and 36 months. Of 1241 high-risk siblings, 252 had ASD outcomes. Male recurrence was 26.7 % and female recurrence 10.3 %, with a 3.18 odds ratio. The HR-ASD group had lower MSEL subscale scores and higher RRB and SA scores than the HR non-ASD group, which had lower MSEL subscale scores and higher RRB scores than the LR group. Regardless of group, males obtained lower MSEL subscale scores, and higher ADOS RRB scores, than females. There were, however, no significant interactions between sex and group on either the MSEL or ADOS. Proband sex did not affect ASD outcome, MSEL subscale, or ADOS domain scores. A 3.2:1 male:female odds ratio emerged among a large sample of prospectively followed high-risk siblings. Sex differences in cognitive performance and repetitive behaviors were apparent not only in high-risk children with ASD, but also in high-risk children without ASD and in low-risk children. Sex differences in young children with ASD do not appear to be ASD-specific but instead reflect typically occurring sex differences seen in children without ASD. Results did not support a female protective effect hypothesis.

Developmental trajectories of paediatric headache - sex-specific analyses and predictors.

PubMed

Isensee, Corinna; Fernandez Castelao, Carolin; Kröner-Herwig, Birgit

2016-01-01

Headache is the most common pain disorder in children and adolescents and is associated with diverse dysfunctions and psychological symptoms. Several studies evidenced sex-specific differences in headache frequency. Until now no study exists that examined sex-specific patterns of change in paediatric headache across time and included pain-related somatic and (socio-)psychological predictors. Latent Class Growth Analysis (LCGA) was used in order to identify different trajectory classes of headache across four annual time points in a population-based sample (n = 3 227; mean age 11.34 years; 51.2 % girls). In multinomial logistic regression analyses the influence of several predictors on the class membership was examined. For girls, a four-class model was identified as the best fitting model. While the majority of girls reported no (30.5 %) or moderate headache frequencies (32.5 %) across time, one class with a high level of headache days (20.8 %) and a class with an increasing headache frequency across time (16.2 %) were identified. For boys a two class model with a 'no headache class' (48.6 %) and 'moderate headache class' (51.4 %) showed the best model fit. Regarding logistic regression analyses, migraine and parental headache proved to be stable predictors across sexes. Depression/anxiety was a significant predictor for all pain classes in girls. Life events, dysfunctional stress coping and school burden were also able to differentiate at least between some classes in both sexes. The identified trajectories reflect sex-specific differences in paediatric headache, as seen in the number and type of classes extracted. The documented risk factors can deliver ideas for preventive actions and considerations for treatment programmes.

Age-related sex differences in body condition and telomere dynamics of red-sided garter snakes

PubMed Central

Rollings, Nicky; Uhrig, Emily J.; Krohmer, Randolph W.; Waye, Heather L.; Mason, Robert T.; Olsson, Mats; Whittington, Camilla M.

2017-01-01

Life-history strategies vary dramatically between the sexes, which may drive divergence in sex-specific senescence and mortality rates. Telomeres are tandem nucleotide repeats that protect the ends of chromosomes from erosion during cell division. Telomeres have been implicated in senescence and mortality because they tend to shorten with stress, growth and age. We investigated age-specific telomere length in female and male red-sided garter snakes, Thamnophis sirtalis parietalis. We hypothesized that age-specific telomere length would differ between males and females given their divergent reproductive strategies. Male garter snakes emerge from hibernation with high levels of corticosterone, which facilitates energy mobilization to fuel mate-searching, courtship and mating behaviours during a two to four week aphagous breeding period at the den site. Conversely, females remain at the dens for only about 4 days and seem to invest more energy in growth and cellular maintenance, as they usually reproduce biennially. As male investment in reproduction involves a yearly bout of physiologically stressful activities, while females prioritize self-maintenance, we predicted male snakes would experience more age-specific telomere loss than females. We investigated this prediction using skeletochronology to determine the ages of individuals and qPCR to determine telomere length in a cross-sectional study. For both sexes, telomere length was positively related to body condition. Telomere length decreased with age in male garter snakes, but remained stable in female snakes. There was no correlation between telomere length and growth in either sex, suggesting that our results are a consequence of divergent selection on life histories of males and females. Different selection on the sexes may be the physiological consequence of the sexual dimorphism and mating system dynamics displayed by this species. PMID:28381620

Age-related sex differences in body condition and telomere dynamics of red-sided garter snakes.

PubMed

Rollings, Nicky; Uhrig, Emily J; Krohmer, Randolph W; Waye, Heather L; Mason, Robert T; Olsson, Mats; Whittington, Camilla M; Friesen, Christopher R

2017-04-12

Life-history strategies vary dramatically between the sexes, which may drive divergence in sex-specific senescence and mortality rates. Telomeres are tandem nucleotide repeats that protect the ends of chromosomes from erosion during cell division. Telomeres have been implicated in senescence and mortality because they tend to shorten with stress, growth and age. We investigated age-specific telomere length in female and male red-sided garter snakes, Thamnophis sirtalis parietalis We hypothesized that age-specific telomere length would differ between males and females given their divergent reproductive strategies. Male garter snakes emerge from hibernation with high levels of corticosterone, which facilitates energy mobilization to fuel mate-searching, courtship and mating behaviours during a two to four week aphagous breeding period at the den site. Conversely, females remain at the dens for only about 4 days and seem to invest more energy in growth and cellular maintenance, as they usually reproduce biennially. As male investment in reproduction involves a yearly bout of physiologically stressful activities, while females prioritize self-maintenance, we predicted male snakes would experience more age-specific telomere loss than females. We investigated this prediction using skeletochronology to determine the ages of individuals and qPCR to determine telomere length in a cross-sectional study. For both sexes, telomere length was positively related to body condition. Telomere length decreased with age in male garter snakes, but remained stable in female snakes. There was no correlation between telomere length and growth in either sex, suggesting that our results are a consequence of divergent selection on life histories of males and females. Different selection on the sexes may be the physiological consequence of the sexual dimorphism and mating system dynamics displayed by this species. © 2017 The Author(s).

The sex of specific neurons controls female body growth in Drosophila.

PubMed

Sawala, Annick; Gould, Alex P

2017-10-01

Sexual dimorphisms in body size are widespread throughout the animal kingdom but their underlying mechanisms are not well characterized. Most models for how sex chromosome genes specify size dimorphism have emphasized the importance of gonadal hormones and cell-autonomous influences in mammals versus strictly cell-autonomous mechanisms in Drosophila melanogaster. Here, we use tissue-specific genetics to investigate how sexual size dimorphism (SSD) is established in Drosophila. We find that the larger body size characteristic of Drosophila females is established very early in larval development via an increase in the growth rate per unit of body mass. We demonstrate that the female sex determination gene, Sex-lethal (Sxl), functions in central nervous system (CNS) neurons as part of a relay that specifies the early sex-specific growth trajectories of larval but not imaginal tissues. Neuronal Sxl acts additively in 2 neuronal subpopulations, one of which corresponds to 7 median neurosecretory cells: the insulin-producing cells (IPCs). Surprisingly, however, male-female differences in the production of insulin-like peptides (Ilps) from the IPCs do not appear to be involved in establishing SSD in early larvae, although they may play a later role. These findings support a relay model in which Sxl in neurons and Sxl in local tissues act together to specify the female-specific growth of the larval body. They also reveal that, even though the sex determination pathways in Drosophila and mammals are different, they both modulate body growth via a combination of tissue-autonomous and nonautonomous inputs.

The sex of specific neurons controls female body growth in Drosophila

PubMed Central

Sawala, Annick

2017-01-01

Sexual dimorphisms in body size are widespread throughout the animal kingdom but their underlying mechanisms are not well characterized. Most models for how sex chromosome genes specify size dimorphism have emphasized the importance of gonadal hormones and cell-autonomous influences in mammals versus strictly cell-autonomous mechanisms in Drosophila melanogaster. Here, we use tissue-specific genetics to investigate how sexual size dimorphism (SSD) is established in Drosophila. We find that the larger body size characteristic of Drosophila females is established very early in larval development via an increase in the growth rate per unit of body mass. We demonstrate that the female sex determination gene, Sex-lethal (Sxl), functions in central nervous system (CNS) neurons as part of a relay that specifies the early sex-specific growth trajectories of larval but not imaginal tissues. Neuronal Sxl acts additively in 2 neuronal subpopulations, one of which corresponds to 7 median neurosecretory cells: the insulin-producing cells (IPCs). Surprisingly, however, male-female differences in the production of insulin-like peptides (Ilps) from the IPCs do not appear to be involved in establishing SSD in early larvae, although they may play a later role. These findings support a relay model in which Sxl in neurons and Sxl in local tissues act together to specify the female-specific growth of the larval body. They also reveal that, even though the sex determination pathways in Drosophila and mammals are different, they both modulate body growth via a combination of tissue-autonomous and nonautonomous inputs. PMID:28976974

Doublesex and mab-3 related transcription factor 1 (DMRT1) is a sex-specific genetic determinant of childhood-onset asthma and is expressed in testis and macrophages.

PubMed

Schieck, Maximilian; Schouten, Jan P; Michel, Sven; Suttner, Kathrin; Toncheva, Antoaneta A; Gaertner, Vincent D; Illig, Thomas; Lipinski, Simone; Franke, Andre; Klintschar, Michael; Kalayci, Omer; Sahiner, Umit M; Birben, Esra; Melén, Erik; Pershagen, Göran; Freidin, Maxim B; Ogorodova, Ludmila M; Granell, Raquel; Henderson, John; Brunekreef, Bert; Smit, Henriëtte A; Vogelberg, Christian; von Berg, Andrea; Bufe, Albrecht; Heinzmann, Andrea; Laub, Otto; Rietschel, Ernst; Simma, Burkhard; Genuneit, Jon; Jonigk, Danny; Postma, Dirkje S; Koppelman, Gerard H; Vonk, Judith M; Timens, Wim; Boezen, H Marike; Kabesch, Michael

2016-08-01

Asthma is a disease affecting more boys than girls in childhood and more women than men in adulthood. The mechanisms behind these sex-specific differences are not yet understood. We analyzed whether and how genetic factors contribute to sex-specific predisposition to childhood-onset asthma. Interactions between sex and polymorphisms on childhood asthma risk were evaluated in the Multicentre Asthma Genetics in Childhood Study (MAGICS)/Phase II International Study of Asthma and Allergies in Childhood (ISAAC II) population on a genome-wide level, and findings were validated in independent populations. Genetic fine mapping of sex-specific asthma association signals was performed, and putatively causal polymorphisms were characterized in vitro by using electrophoretic mobility shift and luciferase activity assays. Gene and protein expression of the identified gene doublesex and mab-3 related transcription factor 1 (DMRT1) were measured in different human tissues by using quantitative real-time PCR and immunohistochemistry. Polymorphisms in the testis-associated gene DMRT1 displayed interactions with sex on asthma status in a population of primarily clinically defined asthmatic children and nonasthmatic control subjects (lowest P = 5.21 × 10(-6)). Replication of this interaction was successful in 2 childhood populations clinically assessed for asthma but showed heterogeneous results in other population-based samples. Polymorphism rs3812523 located in the putative DMRT1 promoter was associated with allele-specific changes in transcription factor binding and promoter activity in vitro. DMRT1 expression was observed not only in the testis but also in lung macrophages. DMRT1 might influence sex-specific patterns of childhood asthma, and its expression in testis tissue and lung macrophages suggests a potential involvement in hormone or immune cell regulation. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. All rights reserved.

A simple PCR-based marker to determine sex in aspen.

PubMed

Pakull, B; Kersten, B; Lüneburg, J; Fladung, M

2015-01-01

The genus Populus features a genetically controlled sex determination system, located on chromosome 19. However, different Populus species vary in the position of the sex-linked region on the respective chromosome and the apparent heterogametic sex, and the precise mechanism of sex determination in Populus is still unknown. Using next generation sequencing of pooled samples of male and female aspens, we identified the aspen homologue of the P. trichocarpa gene Potri.019G047300 ('TOZ19') to be male-specific. While in P. tremuloides, the complete gene is missing in the genome of female plants, a short fragment of the 3'-part of the gene is still present in P. tremula females. The male-specific presence and transcription of TOZ19 was further verified using PCR in various different aspen individuals and RT-PCR expression analysis. TOZ19 is potentially involved in early steps of flower development, and represents an interesting candidate gene for involvement in sex determination in aspen. Regardless of its role as candidate gene, TOZ19 represents an ideal marker for determination of the sex of non-flowering aspen individuals or seedlings. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

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

PubMed

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

2015-07-01

The Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes have been intensively studied because they represent major transcription factors in the pathways governing sex determination and differentiation. These genes have been identified in animal groups ranging from cnidarians to mammals, and some of the genes functionally studied. Here, we propose to analyze (i) the presence/absence of various Dmrt gene groups in the different taxa across the animal kingdom; (ii) the relative expression levels of the Dmrt genes in each sex; (iii) the specific spatial (by organ) and temporal (by developmental stage) variations in gene expression. This review considers non-mammalian animals at all levels of study (i.e. no particular importance is given to animal models), and using all types of sexual strategy (hermaphroditic or gonochoric) and means of sex determination (i.e. genetic or environmental). To conclude this global comparison, we offer an analysis of the DM domains conserved among the different DMRT proteins, and propose a general sex-specific pattern for each member of the Dmrt gene family. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Sex determination in insects: a binary decision based on alternative splicing.

PubMed

Salz, Helen K

2011-08-01

The gene regulatory networks that control sex determination vary between species. Despite these differences, comparative studies in insects have found that alternative splicing is reiteratively used in evolution to control expression of the key sex-determining genes. Sex determination is best understood in Drosophila where activation of the RNA binding protein-encoding gene Sex-lethal is the central female-determining event. Sex-lethal serves as a genetic switch because once activated it controls its own expression by a positive feedback splicing mechanism. Sex fate choice in is also maintained by self-sustaining positive feedback splicing mechanisms in other dipteran and hymenopteran insects, although different RNA binding protein-encoding genes function as the binary switch. Studies exploring the mechanisms of sex-specific splicing have revealed the extent to which sex determination is integrated with other developmental regulatory networks. Copyright © 2011 Elsevier Ltd. All rights reserved.

Sex-specific genetic effects in physical activity: results from a quantitative genetic analysis.

PubMed

Diego, Vincent P; de Chaves, Raquel Nichele; Blangero, John; de Souza, Michele Caroline; Santos, Daniel; Gomes, Thayse Natacha; dos Santos, Fernanda Karina; Garganta, Rui; Katzmarzyk, Peter T; Maia, José A R

2015-08-01

The objective of this study is to present a model to estimate sex-specific genetic effects on physical activity (PA) levels and sedentary behaviour (SB) using three generation families. The sample consisted of 100 families covering three generations from Portugal. PA and SB were assessed via the International Physical Activity Questionnaire short form (IPAQ-SF). Sex-specific effects were assessed by genotype-by-sex interaction (GSI) models and sex-specific heritabilities. GSI effects and heterogeneity were tested in the residual environmental variance. SPSS 17 and SOLAR v. 4.1 were used in all computations. The genetic component for PA and SB domains varied from low to moderate (11% to 46%), when analyzing both genders combined. We found GSI effects for vigorous PA (p = 0.02) and time spent watching television (WT) (p < 0.001) that showed significantly higher additive genetic variance estimates in males. The heterogeneity in the residual environmental variance was significant for moderate PA (p = 0.02), vigorous PA (p = 0.006) and total PA (p = 0.001). Sex-specific heritability estimates were significantly higher in males only for WT, with a male-to-female difference in heritability of 42.5 (95% confidence interval: 6.4, 70.4). Low to moderate genetic effects on PA and SB traits were found. Results from the GSI model show that there are sex-specific effects in two phenotypes, VPA and WT with a stronger genetic influence in males.

The different role of sex hormones on female cardiovascular physiology and function: not only oestrogens.

PubMed

Salerni, Sara; Di Francescomarino, Samanta; Cadeddu, Christian; Acquistapace, Flavio; Maffei, Silvia; Gallina, Sabina

2015-06-01

Human response to different physiologic stimuli and cardiovascular (CV) adaptation to various pathologies seem to be gender specific. Sex-steroid hormones have been postulated as the major contributors towards these sex-related differences. This review will discuss current evidence on gender differences in CV function and remodelling, and will present the different role of the principal sex-steroid hormones on female heart. Starting from a review of sex hormones synthesis, receptors and CV signalling, we will summarize the current knowledge concerning the role of sex hormones on the regulation of our daily activities throughout the life, via the modulation of autonomic nervous system, excitation-contraction coupling pathway and ion channels activity. Many unresolved questions remain even if oestrogen effects on myocardial remodelling and function have been extensively studied. So this work will focus attention also on the controversial and complex relationship existing between androgens, progesterone and female heart. © 2015 Stichting European Society for Clinical Investigation Journal Foundation.

Sex differences in the developing brain as a source of inherent risk

PubMed Central

McCarthy, Margaret M.

2016-01-01

Brain development diverges in males and females in response to androgen production by the fetal testis. This sexual differentiation of the brain occurs during a sensitive window and induces enduring neuroanatomical and physiological changes that profoundly impact behavior. What we know about the contribution of sex chromosomes is still emerging, highlighting the need to integrate multiple factors into understanding sex differences, including the importance of context. The cellular mechanisms are best modeled in rodents and have provided both unifying principles and surprising specifics. Markedly distinct signaling pathways direct differentiation in specific brain regions, resulting in mosaicism of relative maleness, femaleness, and sameness through-out the brain, while canalization both exaggerates and constrains sex differences. Non-neuronal cells and inflammatory mediators are found in greater number and at higher levels in parts of male brains. This higher baseline of inflammation is speculated to increase male vulnerability to developmental neuropsychiatric disorders that are triggered by inflammation. PMID:28179808

Sex differences in a shoaling-boldness behavioral syndrome, but no link with aggression.

PubMed

Way, Gregory P; Kiesel, Alexis L; Ruhl, Nathan; Snekser, Jennifer L; McRobert, Scott P

2015-04-01

A behavioral syndrome is observed in a population when specific behaviors overlap at the individual level in different contexts. Here, we explore boldness and aggression personality spectra, the repeatability of shoaling, and possible associated correlations between the behaviors in a population of lab-reared zebrafish (Danio rerio). Our findings describe a sex-specific boldness-shoaling behavioral syndrome, as a link between boldness and shoaling behaviors is detected. The results indicate that bold males are likely to have a stronger shoaling propensity than shy males for unfamiliar conspecifics. Conversely, bold females are more likely to shoal than shy females, but only when presented with heterospecific individuals. Additionally, aggression does not correlate with boldness or shoaling propensity for either sex. A positive relationship between boldness and shoaling that differs by sex is contrary to most of the present literature, but could help to explain population dynamics and may also have evolutionary implications. Copyright © 2015 Elsevier B.V. All rights reserved.

Role of sex in the treatment and clinical outcomes of pediatric patients with inflammatory bowel disease.

PubMed

Lee, Grace J; Kappelman, Michael D; Boyle, Brendan; Colletti, Richard B; King, Eileen; Pratt, Jesse M; Crandall, Wallace V

2012-12-01

To examine sex differences in medical therapy and clinical outcomes in pediatric patients with inflammatory bowel disease (IBD). We performed a cross-sectional analysis of children with Crohn disease (CD) and ulcerative colitis (UC) using data from the ImproveCareNow Network collected between May 2007 and May 2010. Clinical remission, disease severity, body mass index (BMI) z scores, normal height velocity, and medication use were analyzed by sex and age. One thousand four hundred nine patients were included (993 had CD and 416 had UC). No significant sex differences were found in disease severity, BMI, height velocity, or use of medications. Further analysis of combination therapy with infliximab + 6-mercaptopurine/azathioprine and infliximab + methotrexate also did not reveal any differences. No sex differences were found after mediation use was stratified by age (those younger than 13 years and those 13 years old or older). In this sample of CD and UC pediatric patients, no significant sex differences were found in disease severity, BMI, height velocity, or medication use. Our data do not support the use of sex as a major factor in patient risk stratification for children with IBD. In addition, despite concerns for sex-specific complications of some medications, our analysis did not suggest any sex differences in medication use.

Families, resources, and adult health: where do sexual minorities fit?

PubMed

Denney, Justin T; Gorman, Bridget K; Barrera, Cristina B

2013-03-01

Extensive research documents the relevance of families and socioeconomic resources to health. This article extends that research to sexual minorities, using 12 years of the National Health Interview Survey (N = 460,459) to examine self-evaluations of health among male and female adults living in same-sex and different-sex relationships. Adjusting for socioeconomic status eliminates differences between same- and different-sex cohabitors so that they have similarly higher odds of poor health relative to married persons. Results by gender reveal that the cohabitation disadvantage for health is more pronounced for different-sex cohabiting women than for men, but little difference exists between same-sex cohabiting men and women. Finally, the presence of children in the home is more protective for women's than men's health, but those protections are specific to married women. In all, the results elucidate the importance of relationship type, gender, and the presence of children when evaluating health.

Multivariate selection and intersexual genetic constraints in a wild bird population.

PubMed

Poissant, J; Morrissey, M B; Gosler, A G; Slate, J; Sheldon, B C

2016-10-01

When selection differs between the sexes for traits that are genetically correlated between the sexes, there is potential for the effect of selection in one sex to be altered by indirect selection in the other sex, a situation commonly referred to as intralocus sexual conflict (ISC). While potentially common, ISC has rarely been studied in wild populations. Here, we studied ISC over a set of morphological traits (wing length, tarsus length, bill depth and bill length) in a wild population of great tits (Parus major) from Wytham Woods, UK. Specifically, we quantified the microevolutionary impacts of ISC by combining intra- and intersex additive genetic (co)variances and sex-specific selection estimates in a multivariate framework. Large genetic correlations between homologous male and female traits combined with evidence for sex-specific multivariate survival selection suggested that ISC could play an appreciable role in the evolution of this population. Together, multivariate sex-specific selection and additive genetic (co)variance for the traits considered accounted for additive genetic variance in fitness that was uncorrelated between the sexes (cross-sex genetic correlation = -0.003, 95% CI = -0.83, 0.83). Gender load, defined as the reduction in a population's rate of adaptation due to sex-specific effects, was estimated at 50% (95% CI = 13%, 86%). This study provides novel insights into the evolution of sexual dimorphism in wild populations and illustrates how quantitative genetics and selection analyses can be combined in a multivariate framework to quantify the microevolutionary impacts of ISC. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

Multiculturalism and inconsistency in the perception of sex education in Australian society.

PubMed

Almahbobi, Ghanim

2012-01-01

A group of individuals who share common beliefs form a culture in which they communicate their values and attributes about certain aspects of society. Sex education remains one of the early teachings that humans experience irrespective of the race or level of development of a given society. However, different cultures perceive sex education differently due to differences in attitudes and beliefs, leading to significant diversity in the management of sex education among different societies across the globe. Many studies have found that in a traditional society with a homogeneous culture, the foremost reason for the different approaches to sex education is related to traditional values, in addition to other factors such as religion and political belief. In order to improve sex education, and consequently, sexual health in a modern multicultural society such as Australia, it becomes imperative to identify the inconsistency in beliefs about sex education among individuals with different cultural backgrounds in the Australian population. In this report, the author highlights similarities and differences in the methods employed by certain cultures of the Australian population. The report considers the different cultural environments of specific societies, the prevalence of sex education in these societies and how culture influences the prevalence. The concluding thoughts reflect on the success of the education programs in Australia, based on the idea that resolving the problems of sex education needs support from a number of bodies within Australian society.

Sex differences in depressive, anxious behaviors and hippocampal transcript levels in a genetic rat model.

PubMed

Mehta, N S; Wang, L; Redei, E E

2013-10-01

Major depressive disorder (MDD) is a common, debilitating illness with high prevalence of comorbid anxiety. The incidence of depression and of comorbid anxiety is much higher in women than in men. These gender biases appear after puberty and their etiology is mostly unknown. Selective breeding of the Wistar Kyoto (WKY) rat strain, an accepted model of adult and adolescent depression, resulted in two fully inbred substrains. Adult WKY more immobile (WMI) rats of both sexes consistently show increased depression-like behavior in the forced swim test when compared with the control WKY less immobile (WLI) strain. In contrast, here we show that while adult female WMIs and WLIs both display high anxiety-like behaviors, only WLI males, but not WMI males, show this behavior. Moreover, the behavioral profile of WMI males is consistent from early adolescence to adulthood, but the high depression- and anxiety-like behaviors of the female WMIs appear only in adulthood. These sex-specific behavioral patterns are paralleled by marked sex differences in hippocampal gene expression differences established by genome-wide transcriptional analyses of 13th generation WMIs and WLIs. Moreover, sex- and age-specific differences in transcript levels of selected genes are present in the hippocampus of the current, fully inbred WMIs and WLIs. Thus, the contribution of specific genes and/or the influence of the gonadal hormonal environment to depression- and anxiety-like behaviors may differ between male and female WMIs, resulting in their distinct behavioral and transcriptomic profiles despite shared sequences of the somatic chromosomes. © 2013 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Sex differences in empathy for pain: What is the role of autonomic regulation?

PubMed

Tracy, Lincoln M; Giummarra, Melita J

2017-10-01

Empathy involves both affective and cognitive components whereby we understand, and express concerns for, the experiences of others. Women typically have superior trait empathy compared with men, which seems to have a neurological basis with sex differences in the structure and function of neural networks involved in empathy. This study investigated sex differences in empathy for pain using the Empathy for Pain Scale, and examined whether these trait differences were associated with disruptions in autonomic regulation, specifically via the parasympathetic nervous system (measured through the square root of the mean squared differences of successive R-R intervals; RMSSD) both at rest and during a socioevaluative stress task (i.e., the serial sevens task). Compared with men, women reported higher empathic concern (Cohen's r = .25) and affective distress (Cohen's d = 0.65) toward another in pain. In both men and women, there was a decrease in lnRMSSD in the stress task compared to rest. Sex moderated the relationship between resting lnRMSSD and self-reported empathic concern. Specifically, there was no clear association between empathic concern and lnRMSSD in men whereas in women there was a negative relationship, with lower resting lnRMSSD associated with higher empathic concern, and higher lnRMSSD associated with lower levels of empathic concern that were similar to men. These findings suggest that empathic feelings may result from poorer psychophysiological regulation, and concur with previous research displaying sex-specific relationships between resting heart rate variability and emotion regulation abilities. © 2017 Society for Psychophysiological Research.

What Does Sex Have to Do with It? The Role of Sex as a Biological Variable in the Development of Posttraumatic Stress Disorder.

PubMed

Kornfield, Sara L; Hantsoo, Liisa; Epperson, C Neill

2018-05-18

This review highlights the neurobiological aspects of sex differences in posttraumatic stress disorder (PTSD), specifically focusing on the physiological responses to trauma and presents evidence supporting hormone and neurosteroid/peptide differences from both preclinical and clinical research. While others have suggested that trauma type or acute emotional reaction are responsible for women's disproportionate risk to PTSD, neither of these explanations fully accounts for the sex differences in PTSD. Sex differences in brain neurocircuitry, anatomy, and neurobiological processes, such as those involved in learning and memory, are discussed as they have been implicated in risk and resilience for the development of PTSD. Gonadal and stress hormones have been found to modulate sex differences in the neurocircuitry and neurochemistry underlying fear learning and extinction. Preclinical research has not consistently controlled for hormonal and reproductive status of rodents nor have clinical studies consistently examined these factors as potential moderators of risk for PTSD. Sex as a biological variable (SABV) should be considered, in addition to the endocrine and reproductive status of participants, in all stress physiology and PTSD research.

Transactional sex risk across a typology of rural and urban female sex workers in Indonesia: a mixed methods study.

PubMed

Puradiredja, Dewi Ismajani; Coast, Ernestina

2012-01-01

Context-specific typologies of female sex workers (FSWs) are essential for the design of HIV intervention programming. This study develops a novel FSW typology for the analysis of transactional sex risk in rural and urban settings in Indonesia. Mixed methods include a survey of rural and urban FSWs (n=310), in-depth interviews (n=11), key informant interviews (n=5) and ethnographic assessments. Thematic analysis categorises FSWs into 5 distinct groups based on geographical location of their sex work settings, place of solicitation, and whether sex work is their primary occupation. Multiple regression analysis shows that the likelihood of consistent condom use was higher among urban venue-based FSWs for whom sex work is not the only source of income than for any of the other rural and urban FSW groups. This effect was explained by the significantly lower likelihood of consistent condom use by rural venue-based FSWs (adjusted OR: 0.34 95% CI 0.13-0.90, p=0.029). The FSW typology and differences in organisational features and social dynamics are more closely related to the risk of unprotected transactional sex, than levels of condom awareness and availability. Interventions need context-specific strategies to reach the different FSWs identified by this study's typology.

Caenorhabditis elegans Male Copulation Circuitry Incorporates Sex-Shared Defecation Components To Promote Intromission and Sperm Transfer

PubMed Central

LeBoeuf, Brigitte; Garcia, L. Rene

2016-01-01

Sexual dimorphism can be achieved using a variety of mechanisms, including sex-specific circuits and sex-specific function of shared circuits, though how these work together to produce sexually dimorphic behaviors requires further investigation. Here, we explore how components of the sex-shared defecation circuitry are incorporated into the sex-specific male mating circuitry in Caenorhabditis elegans to produce successful copulation. Using behavioral studies, calcium imaging, and genetic manipulation, we show that aspects of the defecation system are coopted by the male copulatory circuitry to facilitate intromission and ejaculation. Similar to hermaphrodites, male defecation is initiated by an intestinal calcium wave, but circuit activity is coordinated differently during mating. In hermaphrodites, the tail neuron DVB promotes expulsion of gut contents through the release of the neurotransmitter GABA onto the anal depressor muscle. However, in the male, both neuron and muscle take on modified functions to promote successful copulation. Males require calcium-dependent activator protein for secretion (CAPS)/unc-31, a dense core vesicle exocytosis activator protein, in the DVB to regulate copulatory spicule insertion, while the anal depressor is remodeled to promote release of sperm into the hermaphrodite. This work shows how sex-shared circuitry is modified in multiple ways to contribute to sex-specific mating. PMID:28031243

Characterization and application of a quantitative DNA marker that discriminates sex in Chinook salmon (Oncorhynchus tshawytscha)

USGS Publications Warehouse

Clifton, D.R.; Rodriguez, R.J.

1997-01-01

A qualitative male-specific DNA marker (OT-24) was amplified by spPCR (single-primer polymerase chain reaction) from chinook salmon (Oncorhynchus tshawytscha) DNA along with several non-sex-linked products. The termini of the male-specific product were sequenced, and a pair of PeR primers were constructed for marker-specific PCR amplification. Dual primer PCR (dpPCR), with the marker-specific primers, amplified a product from both nudes and females. The amount of dpPCR product amplified from males was at least 100-fold greater than that from females. The quantitative difference between males and females was consistent among geographically distinct populations from western U.S. rivers. In addition, DNA sequence analysis indicated that OT-24 was highly conserved among geographically distinct salmon populations. The qualitative spPCR product segregated through several genetic crosses indicating equal sex ratios among progeny. Identification of the male and female juveniles by dpPCR was consistent with the spPCR analysis. There was no tissue specificity observed by spPCR or dpPCR analysis of this marker. A rapid DNA extraction method and dpPCR analysis were used to nonlethally determine sex ratios in wild spring chinook salmon adults, withheld for genetic and behavioral studies, prior to their development of gross sexual differences in their external morphology.

Characterization and application of a quantitative DNA marker that discriminates sex in chinook salmon (Oncorhynchus tshawytscha)

USGS Publications Warehouse

Clifton, D.R.; Rodriguez, R.J.

1997-01-01

A qualitative male-specific DNA marker (OT-24) was amplified by spPCR (single-primer polymerase chain reaction) from chinook salmon (Oncorhynchus tshawytscha) DNA along with several non-sex-linked products. The termini of the male-specific product were sequenced, and a pair of PeR primers were constructed for marker-specific PCR amplification. Dual primer PCR (dpPCR), with the marker-specific primers, amplified a product from both nudes and females. The amount of dpPCR product amplified from males was at least 100-fold greater than that from females. The quantitative difference between males and females was consistent among geographically distinct populations from western U.S. rivers. In addition, DNA sequence analysis indicated that OT-24 was highly conserved among geographically distinct salmon populations. The qualitative spPCR product segregated through several genetic crosses indicating equal sex ratios among progeny. Identification of the male and female juveniles by dpPCR was consistent with the spPCR analysis. There was no tissue specificity observed by spPCR or dpPCR analysis of this marker. A rapid DNA extraction method and dpPCR analysis were used to nonlethally determine sex ratios in wild spring chinook salmon adults, withheld for genetic and behavioral studies, prior to their development of gross sexual differences in their external morphology.

The landscape of sex-differential transcriptome and its consequent selection in human adults.

PubMed

Gershoni, Moran; Pietrokovski, Shmuel

2017-02-07

The prevalence of several human morbid phenotypes is sometimes much higher than intuitively expected. This can directly arise from the presence of two sexes, male and female, in one species. Men and women have almost identical genomes but are distinctly dimorphic, with dissimilar disease susceptibilities. Sexually dimorphic traits mainly result from differential expression of genes present in both sexes. Such genes can be subject to different, and even opposing, selection constraints in the two sexes. This can impact human evolution by differential selection on mutations with dissimilar effects on the two sexes. We comprehensively mapped human sex-differential genetic architecture across 53 tissues. Analyzing available RNA-sequencing data from 544 adults revealed thousands of genes differentially expressed in the reproductive tracts and tissues common to both sexes. Sex-differential genes are related to various biological systems, and suggest new insights into the pathophysiology of diverse human diseases. We also identified a significant association between sex-specific gene transcription and reduced selection efficiency and accumulation of deleterious mutations, which might affect the prevalence of different traits and diseases. Interestingly, many of the sex-specific genes that also undergo reduced selection efficiency are essential for successful reproduction in men or women. This seeming paradox might partially explain the high incidence of human infertility. This work provides a comprehensive overview of the sex-differential transcriptome and its importance to human evolution and human physiology in health and in disease.

Exploring Sex Differences in Worry with a Cognitive Vulnerability Model

ERIC Educational Resources Information Center

Zalta, Alyson K.; Chambless, Dianne L.

2008-01-01

A multivariate model was developed to examine the relative contributions of mastery, stress, interpretive bias, and coping to sex differences in worry. Rumination was incorporated as a second outcome variable to test the specificity of these associations. Participants included two samples of undergraduates totaling 302 men and 379 women. A path…

When Do Ladies Talk Like Ladies?

ERIC Educational Resources Information Center

Menzel, Peter; Tyler, Mary

As Labov points out (1971), language is a social phenomenon, and therefore must be studied in its social context; sex based language differences, being part of language, must be studied in the same way. Specifically, sex based language differences can be studied by modifying the sociolinguists' notion of speech community and speech continuum, and…

Sex-Specific Differences in Shoaling Affect Parasite Transmission in Guppies

PubMed Central

Richards, E. Loys; van Oosterhout, Cock; Cable, Joanne

2010-01-01

Background Individuals have to trade-off the costs and benefits of group membership during shoaling behaviour. Shoaling can increase the risk of parasite transmission, but this cost has rarely been quantified experimentally. Guppies (Poecilia reticulata) are a model system for behavioural studies, and they are commonly infected by gyrodactylid parasites, notorious fish pathogens that are directly transmitted between guppy hosts. Methodology/Principal Findings Parasite transmission in single sex shoals of male and female guppies were observed using an experimental infection of Gyrodactylus turnbulli. Parasite transmission was affected by sex-specific differences in host behaviour, and significantly more parasites were transmitted when fish had more frequent and more prolonged contact with each other. Females shoaled significantly more than males and had a four times higher risk to contract an infection. Conclusions/Significance Intersexual differences in host behaviours such as shoaling are driven by differences in natural and sexual selection experienced by both sexes. Here we show that the potential benefits of an increased shoaling tendency are traded off against increased risks of contracting an infectious parasite in a group-living species. PMID:20949014

Neuronal composition of the magnocellular division of the medial preoptic nucleus (MPN mag) is sex specific in the Syrian hamster (Mesocricetus auratus).

PubMed

Richendrfer, Holly A; Swann, Jennifer M

2010-09-10

The magnocellular division of the medial Preoptic nucleus (MPN mag) plays a critical role in the regulation of male sexual behavior in the hamster. Results from previous studies indicated that the number of neurons in the MPN mag is greater in males than females but failed to find significant differences in the volume of the nucleus suggesting that other elements in the nucleus may be greater in the female. The results of the present study, using NeuN to identify neurons, are in line with this hypothesis. The data show that (1) neurons in the MPN mag display two distinct phenotypes, those with a single nucleolus and those with multiple nucleoli; (2) the percentage of each phenotype is sex specific, differing over the course of development and (3) there is no sex difference in the number of glial cells at any age. Sex differences in the numbers of each type are correlated with developmental milestones and suggest that morphological changes are influenced by changes in circulating gonadal steroids during development. 2010 Elsevier B.V. All rights reserved.

Juvenile sex offenders compared to non-sex offenders: a review of the literature 1995-2005.

PubMed

van Wijk, Anton; Vermeiren, Robert; Loeber, Rolf; 't Hart-Kerkhoffs, Lisette; Doreleijers, Theo; Bullens, Ruud

2006-10-01

An unresolved but clinically important issue in the literature on juvenile delinquency is to what extent juvenile sex offenders resemble non-sex offenders with respect to individual, familial, and environmental characteristics. The current article reviewed published studies (1995-2005) comparing sex offenders with non-sex offenders. The 17 articles meeting the inclusion criteria suggest that differences exist between sex offenders and non-sex offenders on personality characteristics, behavioral problems, history of sexual abuse, nonsexual offending, and peer functioning. Inconsistent results were found for demographic factors, family functioning and background, antisocial attitudes, and intellectual and neurological functioning. Although it is likely that sex offenders can be differentiated from nonsex offenders on a number of characteristics, caution is warranted because of methodological differences between studies and small samples size. Also, studies show that sex offenders are a heterogeneous group. Further research should take into account this heterogeneity by including sex offenders from clearly circumscribed groups and investigating characteristics specifically related to sexual behavior.

Biological sex and the risk of cerebral palsy in Victoria, Australia.

PubMed

Reid, Susan M; Meehan, Elaine; Gibson, Catherine S; Scott, Heather; Delacy, Michael J

2016-02-01

Males typically outnumber females in cerebral palsy (CP) cohorts. To better understand this 'male disadvantage' and provide insight into causal pathways to CP, this study used 1983 to 2009 Australian CP and population birth cohorts to identify associations and trends with respect to biological sex and CP. Within birth gestation groups, sex ratios were calculated to evaluate any male excess in the CP cohort compared with livebirths, neonatal deaths, neonatal mortality and survival rates, neonatal survivors, and CP rates in survivors. Sex- and gestation-specific trends in neonatal mortality, CP rates, and CP sex ratios were assessed by plotting their annual frequencies and fitting quadratic curves. Over-representation of males in preterm live births partly explained the male excess in the CP cohort after preterm birth, especially at 28 to 31 weeks. Higher CP rates in male neonatal survivors also contributed to the male excess in CP, particularly at <28 and 37+ weeks. Higher neonatal mortality rates in males at all gestations had little impact on the CP sex ratio. There was no clearly discernible change over time in the CP sex ratio. Gestation-specific associations between sex and CP provide insight into causal pathways to CP and suggest sex-specific differences in response to neuroprotective strategies. © 2016 The Authors. Developmental Medicine & Child Neurology © 2016 Mac Keith Press.

Decomposing self-estimates of intelligence: structure and sex differences across 12 nations.

PubMed

von Stumm, Sophie; Chamorro-Premuzic, Tomas; Furnham, Adrian

2009-05-01

This study examines the structure of self-estimates of intelligence (SEI) across 12 nations (Australia, Austria, Brazil, France, Iran, Israel, Malaysia, South Africa, Spain, Turkey, UK and US). Participants rated themselves on general and specific abilities from three popular models of intelligence: Gardner's multiple intelligences, Sternberg's triarchic theory of intelligence, and Goleman's emotional intelligence. The results showed that (a) laypeople across nations have similar and invariant concepts of intelligence, (b) concepts of intelligence are cross-culturally closely related to academic notions of intellectual ability and (c) sex differences in general and specific SEI favouring men are consistent across countries. Male hubris and female humility in SEI seem independent of sex differences in actual cognitive ability and national levels of masculinity-femininity. Furthermore, international mean differences in general SEI could not be attributed to discrepancies in national intelligence quotient (IQ) levels or to cultural variations.

The evolution of sex-specific virulence in infectious diseases

PubMed Central

Úbeda, Francisco; Jansen, Vincent A. A.

2016-01-01

Fatality rates of infectious diseases are often higher in men than women. Although this difference is often attributed to a stronger immune response in women, we show that differences in the transmission routes that the sexes provide can result in evolution favouring pathogens with sex-specific virulence. Because women can transmit pathogens during pregnancy, birth or breast-feeding, pathogens adapt, evolving lower virulence in women. This can resolve the long-standing puzzle on progression from Human T-cell Lymphotropic Virus Type 1 (HTLV-1) infection to lethal Adult T-cell Leukaemia (ATL); a progression that is more likely in Japanese men than women, while it is equally likely in Caribbean women and men. We argue that breastfeeding, being more prolonged in Japan than in the Caribbean, may have driven the difference in virulence between the two populations. Our finding signifies the importance of investigating the differences in genetic expression profile of pathogens in males and females. PMID:27959327

The evolution of sex-specific virulence in infectious diseases.

PubMed

Úbeda, Francisco; Jansen, Vincent A A

2016-12-13

Fatality rates of infectious diseases are often higher in men than women. Although this difference is often attributed to a stronger immune response in women, we show that differences in the transmission routes that the sexes provide can result in evolution favouring pathogens with sex-specific virulence. Because women can transmit pathogens during pregnancy, birth or breast-feeding, pathogens adapt, evolving lower virulence in women. This can resolve the long-standing puzzle on progression from Human T-cell Lymphotropic Virus Type 1 (HTLV-1) infection to lethal Adult T-cell Leukaemia (ATL); a progression that is more likely in Japanese men than women, while it is equally likely in Caribbean women and men. We argue that breastfeeding, being more prolonged in Japan than in the Caribbean, may have driven the difference in virulence between the two populations. Our finding signifies the importance of investigating the differences in genetic expression profile of pathogens in males and females.

Sex-specific effects of protein and carbohydrate intake on reproduction but not lifespan in Drosophila melanogaster.

PubMed

Jensen, Kim; McClure, Colin; Priest, Nicholas K; Hunt, John

2015-08-01

Modest dietary restriction extends lifespan (LS) in a diverse range of taxa and typically has a larger effect in females than males. Traditionally, this has been attributed to a stronger trade-off between LS and reproduction in females than in males that is mediated by the intake of calories. Recent studies, however, suggest that it is the intake of specific nutrients that extends LS and mediates this trade-off. Here, we used the geometric framework (GF) to examine the sex-specific effects of protein (P) and carbohydrate (C) intake on LS and reproduction in Drosophila melanogaster. We found that LS was maximized at a high intake of C and a low intake of P in both sexes, whereas nutrient intake had divergent effects on reproduction. Male offspring production rate and LS were maximized at the same intake of nutrients, whereas female egg production rate was maximized at a high intake of diets with a P:C ratio of 1:2. This resulted in larger differences in nutrient-dependent optima for LS and reproduction in females than in males, as well as an optimal intake of nutrients for lifetime reproduction that differed between the sexes. Under dietary choice, the sexes followed similar feeding trajectories regulated around a P:C ratio of 1:4. Consequently, neither sex reached their nutritional optimum for lifetime reproduction, suggesting intralocus sexual conflict over nutrient optimization. Our study shows clear sex differences in the nutritional requirements of reproduction in D. melanogaster and joins the growing list of studies challenging the role of caloric restriction in extending LS. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Multivariate neuroanatomical classification of cognitive subtypes in schizophrenia: A support vector machine learning approach

PubMed Central

Gould, Ian C.; Shepherd, Alana M.; Laurens, Kristin R.; Cairns, Murray J.; Carr, Vaughan J.; Green, Melissa J.

2014-01-01

Heterogeneity in the structural brain abnormalities associated with schizophrenia has made identification of reliable neuroanatomical markers of the disease difficult. The use of more homogenous clinical phenotypes may improve the accuracy of predicting psychotic disorder/s on the basis of observable brain disturbances. Here we investigate the utility of cognitive subtypes of schizophrenia – ‘cognitive deficit’ and ‘cognitively spared’ – in determining whether multivariate patterns of volumetric brain differences can accurately discriminate these clinical subtypes from healthy controls, and from each other. We applied support vector machine classification to grey- and white-matter volume data from 126 schizophrenia patients previously allocated to the cognitive spared subtype, 74 cognitive deficit schizophrenia patients, and 134 healthy controls. Using this method, cognitive subtypes were distinguished from healthy controls with up to 72% accuracy. Cross-validation analyses between subtypes achieved an accuracy of 71%, suggesting that some common neuroanatomical patterns distinguish both subtypes from healthy controls. Notably, cognitive subtypes were best distinguished from one another when the sample was stratified by sex prior to classification analysis: cognitive subtype classification accuracy was relatively low (<60%) without stratification, and increased to 83% for females with sex stratification. Distinct neuroanatomical patterns predicted cognitive subtype status in each sex: sex-specific multivariate patterns did not predict cognitive subtype status in the other sex above chance, and weight map analyses demonstrated negative correlations between the spatial patterns of weights underlying classification for each sex. These results suggest that in typical mixed-sex samples of schizophrenia patients, the volumetric brain differences between cognitive subtypes are relatively minor in contrast to the large common disease-associated changes. Volumetric differences that distinguish between cognitive subtypes on a case-by-case basis appear to occur in a sex-specific manner that is consistent with previous evidence of disrupted relationships between brain structure and cognition in male, but not female, schizophrenia patients. Consideration of sex-specific differences in brain organization is thus likely to assist future attempts to distinguish subgroups of schizophrenia patients on the basis of neuroanatomical features. PMID:25379435

Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses

PubMed Central

Neckameyer, Wendi S.

2014-01-01

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. PMID:24789992

Sexually selected sex differences in competitiveness explain sex differences in changes in drinking game participation.

PubMed

Hone, Liana S E; McCullough, Michael

2015-05-14

Drinking games are a risk factor for behavioral and health problems among university students. Previous cross-sectional research by Hone, Carter, and McCullough (2013) replicated well-established sex differences in drinking game behaviors (i.e., that men are more active drinking game participants than are women) and university drinking problems more generally. Hone et al. (2013) also found that these male-specific behavioral patterns are attributable in part to the fact that men's generally unrestricted sexual strategies, plus their social competitiveness, motivate them to participate in drinking games to display their fortitude and compete with same-sex rivals. Here, the authors conducted a study to evaluate with greater causal rigor whether sex differences in sexual restrictedness and social competitiveness-and sex differences in motivations for participating in drinking games in particular-are partially responsible for the sex differences in university students' drinking game behaviors and drinking problems. Sex differences in changes in frequency of drinking game participation were partially mediated by competitive motivations for participating in drinking games and by the effects of social competitiveness on competitive drinking game motivation. These findings lend additional support to the proposition that participation in drinking games is motivated in part by their suitability as a venue for sexual competition in university students' day-to-day lives.

No evidence for sex-specific effects of the maternal social environment on offspring development in Japanese quail (Coturnix japonica).

PubMed

Langen, Esther M A; von Engelhardt, Nikolaus; Goerlich-Jansson, Vivian C

2018-07-01

The social environment of reproducing females can cause physiological changes, with consequences for reproductive investment and offspring development. These prenatal maternal effects are often found to be sex-specific and may have evolved as adaptations, maximizing fitness of male and female offspring for their future environment. Female hormone levels during reproduction are considered a potential mechanism regulating sex allocation in vertebrates: high maternal androgens have repeatedly been linked to increased investment in sons, whereas high glucocorticoid levels are usually related to increased investment in daughters. However, results are not consistent across studies and therefore still inconclusive. In Japanese quail (Coturnix japonica), we previously found that pair-housed females had higher plasma androgen levels and tended to have higher plasma corticosterone levels than group-housed females. In the current study we investigate whether these differences in maternal social environment and physiology affect offspring sex allocation and physiology. Counter to our expectations, we find no effects of the maternal social environment on offspring sex ratio, sex-specific mortality, growth, circulating androgen or corticosterone levels. Also, maternal corticosterone or androgen levels do not correlate with offspring sex ratio or mortality. The social environment during reproduction therefore does not necessarily modify sex allocation and offspring physiology, even if it causes differences in maternal physiology. We propose that maternal effects of the social environment strongly depend upon the type of social stimuli and the timing of changes in the social environment and hormones with respect to the reproductive cycle and meiosis. Copyright © 2018 Elsevier Inc. All rights reserved.

[Gender: new methodological approaches in guideline development].

PubMed

Weinbrenner, Susanne; Lönnfors, Sanna; Babitsch, Birgit

2010-01-01

Gender and diversity have a strong impact on health and illness as evidenced by sex and gender differences in the onset and progression of diseases as well as in diagnosis, therapy, and therapeutic outcome. The number of sex/gender-specific studies in medicine has increased steadily in recent years, indicating sex (biological) and gender (social) differences in numerous diseases. Despite this evidence, however, sex/gender differences are rarely considered in medical practice or in health systems, suggesting a delay in transferring such research into evidence-based medical treatment. Similarly, quality improvement guidelines in medical care do not systematically integrate the sex/gender perspective. Against this backdrop, this paper seeks to enumerate the necessary components of a guideline development and evaluation process that systematically integrates sex/gender differences in addition to providing a sex/gender-based methodological approach. The latter is illustrated by a pilot study in which four international guidelines on depression were selected. The sex/gender appropriateness of these guidelines was analysed using two methods: first, sex/gender-relevant words were counted; and second, relevant sex/gender differences were summarised based on a systematic literature review and then compared with the information given in the guidelines. The findings of the pilot study revealed that although strong evidence exists on sex/gender differences in depression, such research was rarely implemented in the guidelines. Given the scope and potential of guidelines to improve the quality of health care, it is essential that they consider the crucial role of sex/gender differences. To date, sex/gender differences have been insufficiently addressed in guideline development and evaluation when they should be an integral component of the process. Copyright © 2010. Published by Elsevier GmbH.

Sexual dimorphic floral development in dioecious plants revealed by transcriptome, phytohormone, and DNA methylation analysis in Populus tomentosa.

PubMed

Song, Yuepeng; Ma, Kaifeng; Ci, Dong; Chen, Qingqing; Tian, Jiaxing; Zhang, Deqiang

2013-12-01

Dioecious plants have evolved sex-specific floral development mechanisms. However, the precise gene expression patterns in dioecious plant flower development remain unclear. Here, we used andromonoecious poplar, an exceptional model system, to eliminate the confounding effects of genetic background of dioecious plants. Comparative transcriptome and physiological analysis allowed us to characterize sex-specific development of female and male flowers. Transcriptome analysis identified genes significantly differentially expressed between the sexes, including genes related to floral development, phytohormone synthesis and metabolism, and DNA methylation. Correlation analysis revealed a significant correlation between phytohormone signaling and gene expression, identifying specific phytohormone-responsive genes and their cis-regulatory elements. Two genes related to DNA methylation, METHYLTRANSFERASE1 (MET1) and DECREASED DNA METHYLATION 1 (DDM1), which are located in the sex determination region of Chromosome XIX, have differential expression between female and male flowers. A time-course analysis revealed that MET1 and DDM1 expression may produce different DNA methylation levels in female and male flowers. Understanding the interactions of phytohormone signaling, DNA methylation and target gene expression should lead to a better understanding of sexual differences in floral development. Thus, this study identifies a set of candidate genes for further studies of poplar sexual dimorphism and relates sex-specific floral development to physiological and epigenetic changes.

Genetic Mechanisms Leading to Sex Differences Across Common Diseases and Anthropometric Traits.

PubMed

Traglia, Michela; Bseiso, Dina; Gusev, Alexander; Adviento, Brigid; Park, Daniel S; Mefford, Joel A; Zaitlen, Noah; Weiss, Lauren A

2017-02-01

Common diseases often show sex differences in prevalence, onset, symptomology, treatment, or prognosis. Although studies have been performed to evaluate sex differences at specific SNP associations, this work aims to comprehensively survey a number of complex heritable diseases and anthropometric traits. Potential genetically encoded sex differences we investigated include differential genetic liability thresholds or distributions, gene-sex interaction at autosomal loci, major contribution of the X-chromosome, or gene-environment interactions reflected in genes responsive to androgens or estrogens. Finally, we tested the overlap between sex-differential association with anthropometric traits and disease risk. We utilized complementary approaches of assessing GWAS association enrichment and SNP-based heritability estimation to explore explicit sex differences, as well as enrichment in sex-implicated functional categories. We do not find consistent increased genetic load in the lower-prevalence sex, or a disproportionate role for the X-chromosome in disease risk, despite sex-heterogeneity on the X for several traits. We find that all anthropometric traits show less than complete correlation between the genetic contribution to males and females, and find a convincing example of autosome-wide genome-sex interaction in multiple sclerosis (P = 1 × 10 -9 ). We also find some evidence for hormone-responsive gene enrichment, and striking evidence of the contribution of sex-differential anthropometric associations to common disease risk, implying that general mechanisms of sexual dimorphism determining secondary sex characteristics have shared effects on disease risk. Copyright © 2017 by the Genetics Society of America.

Genetic Mechanisms Leading to Sex Differences Across Common Diseases and Anthropometric Traits

PubMed Central

Traglia, Michela; Bseiso, Dina; Gusev, Alexander; Adviento, Brigid; Park, Daniel S.; Mefford, Joel A.; Zaitlen, Noah; Weiss, Lauren A.

2017-01-01

Common diseases often show sex differences in prevalence, onset, symptomology, treatment, or prognosis. Although studies have been performed to evaluate sex differences at specific SNP associations, this work aims to comprehensively survey a number of complex heritable diseases and anthropometric traits. Potential genetically encoded sex differences we investigated include differential genetic liability thresholds or distributions, gene–sex interaction at autosomal loci, major contribution of the X-chromosome, or gene–environment interactions reflected in genes responsive to androgens or estrogens. Finally, we tested the overlap between sex-differential association with anthropometric traits and disease risk. We utilized complementary approaches of assessing GWAS association enrichment and SNP-based heritability estimation to explore explicit sex differences, as well as enrichment in sex-implicated functional categories. We do not find consistent increased genetic load in the lower-prevalence sex, or a disproportionate role for the X-chromosome in disease risk, despite sex-heterogeneity on the X for several traits. We find that all anthropometric traits show less than complete correlation between the genetic contribution to males and females, and find a convincing example of autosome-wide genome-sex interaction in multiple sclerosis (P = 1 × 10−9). We also find some evidence for hormone-responsive gene enrichment, and striking evidence of the contribution of sex-differential anthropometric associations to common disease risk, implying that general mechanisms of sexual dimorphism determining secondary sex characteristics have shared effects on disease risk. PMID:27974502

The Queen's English: an alternative, biosocial hypothesis for the distinctive features of "gay speech".

PubMed

Rendall, Drew; Vasey, Paul L; McKenzie, Jared

2008-02-01

Popular stereotypes concerning the speech of homosexuals typically attribute speech patterns characteristic of the opposite-sex, i.e., broadly feminized speech in gay men and broadly masculinized speech in lesbian women. A small body of recent empirical research has begun to address the subject more systematically and to consider specific mechanistic hypotheses to account for the potentially distinctive features of homosexual speech. Results do not yet fully endorse the stereotypes but they do not entirely discount them either; nor do they cleanly favor any single mechanistic hypothesis. To contribute to this growing body of research, we report acoustic analyses of 2,875 vowel sounds from a balanced set of 125 speakers representing heterosexual and homosexual individuals of each sex from southern Alberta, Canada. Analyses focused on voice pitch and formant frequencies which together determine the principle perceptual features of vowels. There was no significant difference in mean voice pitch between heterosexual and homosexual men or between heterosexual and homosexual women, but there were significant differences in the formant frequencies of vowels produced by both homosexual groups compared to their heterosexual counterparts. Formant frequency differences were specific to only certain vowel sounds and some could be attributed to basic differences in body size between heterosexual and homosexual speakers. The remaining formant frequency differences were not obviously due to differences in vocal tract anatomy between heterosexual and homosexual speakers, nor did they reflect global feminization or masculinization of vowel production patterns in homosexual men and women, respectively. The vowel-specific differences observed could reflect social modeling processes in which only certain speech patterns of the opposite-sex, or of same-sex homosexuals, are selectively adopted. However, we introduce an alternative biosocial hypothesis, specifically that the distinctive, vowel-specific features of homosexual speakers relative to heterosexual speakers arise incidentally as a product of broader psychobehavioral differences between the two groups that are, in turn, continuous with and flow from the physiological processes that affect sexual orientation to begin with.

A Sex-Based Examination of Violence and Aggression Perceptions among Adolescents: An Interactive Qualitative Analysis

ERIC Educational Resources Information Center

Wyatt, Tammy Jordan

2010-01-01

In this study I examine the critical factors and themes that are identified as salient influencers of overt and relational aggression among youth. Sex differences and similarities associated with such adolescent perceptions are assessed. Forty-eight ethnically diverse youth between the ages of 14 and 16 years participated in sex-specific focus…

Specificity of sexual arousal for sexual activities in men and women with conventional and masochistic sexual interests.

PubMed

Chivers, Meredith L; Roy, Carolyn; Grimbos, Teresa; Cantor, James M; Seto, Michael C

2014-07-01

Prior studies consistently report that men's genital responses correspond to their sexual activity interests (consenting vs. coercive sex) whereas women's responses do not. For women, however, these results may be confounded by the sexual activities studied and lack of suitable controls. We examined the subjective and genital arousal responses of men and women with conventional (22 men and 15 women) or masochistic sexual interests (16 men and 17 women) to narratives describing conventional sex or masochistic sex. The aims of the studies were twofold: (1) to examine whether gender differences in the specificity of sexual arousal previously observed for gender also exist for sexual activity interests; and (2) to examine whether men and women with masochistic sexual interests demonstrate specificity of sexual response for their preferred sexual activities. Surprisingly, the pattern of results was very similar for men and women. Both men and women with conventional sexual interests (WCI) reported more sexual arousal, and responded more genitally, to conventional than to masochistic sex, demonstrating specificity of sexual arousal for their preferred sexual activities. Despite showing specificity for conventional sexual activities, the genital responses of WCI were still gender nonspecific. In contrast, women and men with masochistic sexual interests demonstrated nonspecific subjective and genital responses to conventional and masochistic sex. Indices of genital and subjective sexual arousal to masochistic versus conventional stimuli were positively and significantly correlated with self-reported thoughts, fantasies, interests, and behaviors involving masochism. The results suggest that gender similarities in the specificity of sexual arousal for sexual activity exist despite consistent gender differences in the specificity of sexual arousal for gender.

Perinatal BPA exposure alters body weight and composition in a dose specific and sex specific manner: The addition of peripubertal exposure exacerbates adverse effects in female mice

PubMed Central

Rubin, Beverly S.; Paranjpe, Maneesha; DaFonte, Tracey; Schaeberle, Cheryl; Soto, Ana M.; Obin, Martin; Greenberg, Andrew S.

2017-01-01

Body weight (BW) and body composition were examined in CD-1 mice exposed perinatally or perinatally and peripubertally to 0, 0.25, 2.5, 25, or 250 μg BPA/kg BW/day. Our goal was to identify the BPA dose (s) and the exposure window(s) that increased BW and adiposity, and to assess potential sex differences in this response. Both perinatal exposure alone and perinatal plus peripubertal exposure to environmentally relevant levels of BPA resulted in lasting effects on body weight and body composition. The effects were dose specific and sex specific and were influenced by the precise window of BPA exposure. The addition of peripubertal BPA exposure following the initial perinatal exposure exacerbated adverse effects in the females but appeared to reduce differences in body weight and body composition between control and BPA exposed males. Some effects of BPA on body weight and body composition showed a non-linear dose response. PMID:27496714

Untangling the Contributions of Sex-Specific Gene Regulation and X-Chromosome Dosage to Sex-Biased Gene Expression in Caenorhabditis elegans

PubMed Central

Kramer, Maxwell; Rao, Prashant; Ercan, Sevinc

2016-01-01

Dosage compensation mechanisms equalize the level of X chromosome expression between sexes. Yet the X chromosome is often enriched for genes exhibiting sex-biased, i.e., imbalanced expression. The relationship between X chromosome dosage compensation and sex-biased gene expression remains largely unexplored. Most studies determine sex-biased gene expression without distinguishing between contributions from X chromosome copy number (dose) and the animal’s sex. Here, we uncoupled X chromosome dose from sex-specific gene regulation in Caenorhabditis elegans to determine the effect of each on X expression. In early embryogenesis, when dosage compensation is not yet fully active, X chromosome dose drives the hermaphrodite-biased expression of many X-linked genes, including several genes that were shown to be responsible for hermaphrodite fate. A similar effect is seen in the C. elegans germline, where X chromosome dose contributes to higher hermaphrodite X expression, suggesting that lack of dosage compensation in the germline may have a role in supporting higher expression of X chromosomal genes with female-biased functions in the gonad. In the soma, dosage compensation effectively balances X expression between the sexes. As a result, somatic sex-biased expression is almost entirely due to sex-specific gene regulation. These results suggest that lack of dosage compensation in different tissues and developmental stages allow X chromosome copy number to contribute to sex-biased gene expression and function. PMID:27356611

Adaptive Allocation of Attention: Effects of Sex and Sociosexuality on Visual Attention to Attractive Opposite-Sex Faces.

PubMed

Duncan, Lesley A; Park, Justin H; Faulkner, Jason; Schaller, Mark; Neuberg, Steven L; Kenrick, Douglas T

2007-09-01

We tested the hypothesis that, compared with sociosexually restricted individuals, those with an unrestricted approach to mating would selectively allocate visual attention to attractive opposite-sex others. We also tested for sex differences in this effect. Seventy-four participants completed the Sociosexual Orientation Inventory, and performed a computer-based task that assessed the speed with which they detected changes in attractive and unattractive male and female faces. Differences in reaction times served as indicators of selective attention. Results revealed a Sex X Sociosexuality interaction: Compared with sociosexually restricted men, unrestricted men selectively allocated attention to attractive opposite-sex others; no such effect emerged among women. This finding was specific to opposite-sex targets and did not occur in attention to same-sex others. These results contribute to a growing literature on the adaptive allocation of attention in social environments.

Sex-specific influences of mtDNA mitotype and diet on mitochondrial functions and physiological traits in Drosophila melanogaster

PubMed Central

Aw, Wen C.; Garvin, Michael R.; Melvin, Richard G.

2017-01-01

Here we determine the sex-specific influence of mtDNA type (mitotype) and diet on mitochondrial functions and physiology in two Drosophila melanogaster lines. In many species, males and females differ in aspects of their energy production. These sex-specific influences may be caused by differences in evolutionary history and physiological functions. We predicted the influence of mtDNA mutations should be stronger in males than females as a result of the organelle’s maternal mode of inheritance in the majority of metazoans. In contrast, we predicted the influence of diet would be greater in females due to higher metabolic flexibility. We included four diets that differed in their protein: carbohydrate (P:C) ratios as they are the two-major energy-yielding macronutrients in the fly diet. We assayed four mitochondrial function traits (Complex I oxidative phosphorylation, reactive oxygen species production, superoxide dismutase activity, and mtDNA copy number) and four physiological traits (fecundity, longevity, lipid content, and starvation resistance). Traits were assayed at 11 d and 25 d of age. Consistent with predictions we observe that the mitotype influenced males more than females supporting the hypothesis of a sex-specific selective sieve in the mitochondrial genome caused by the maternal inheritance of mitochondria. Also, consistent with predictions, we found that the diet influenced females more than males. PMID:29166659

Evolution of Courtship Songs in Xenopus : Vocal Pattern Generation and Sound Production.

PubMed

Leininger, Elizabeth C; Kelley, Darcy B

2015-01-01

The extant species of African clawed frogs (Xenopus and Silurana) provide an opportunity to link the evolution of vocal characters to changes in the responsible cellular and molecular mechanisms. In this review, we integrate several robust lines of research: evolutionary trajectories of Xenopus vocalizations, cellular and circuit-level mechanisms of vocalization in selected Xenopus model species, and Xenopus evolutionary history and speciation mechanisms. Integrating recent findings allows us to generate and test specific hypotheses about the evolution of Xenopus vocal circuits. We propose that reduced vocal sex differences in some Xenopus species result from species-specific losses of sexually differentiated neural and neuromuscular features. Modification of sex-hormone-regulated developmental mechanisms is a strong candidate mechanism for reduced vocal sex differences.

From swing to cane: Sex differences of EEG resting-state temporal patterns during maturation and aging.

PubMed

Tomescu, M I; Rihs, T A; Rochas, V; Hardmeier, M; Britz, J; Allali, G; Fuhr, P; Eliez, S; Michel, C M

2018-06-01

While many insights on brain development and aging have been gained by studying resting-state networks with fMRI, relating these changes to cognitive functions is limited by the temporal resolution of fMRI. In order to better grasp short-lasting and dynamically changing mental activities, an increasing number of studies utilize EEG to define resting-state networks, thereby often using the concept of EEG microstates. These are brief (around 100 ms) periods of stable scalp potential fields that are influenced by cognitive states and are sensitive to neuropsychiatric diseases. Despite the rising popularity of the EEG microstate approach, information about age changes is sparse and nothing is known about sex differences. Here we investigated age and sex related changes of the temporal dynamics of EEG microstates in 179 healthy individuals (6-87 years old, 90 females, 204-channel EEG). We show strong sex-specific changes in microstate dynamics during adolescence as well as at older age. In addition, males and females differ in the duration and occurrence of specific microstates. These results are of relevance for the comparison of studies in populations of different age and sex and for the understanding of the changes in neuropsychiatric diseases. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Integrative Analysis of Sex-Specific microRNA Networks Following Stress in Mouse Nucleus Accumbens.

PubMed

Pfau, Madeline L; Purushothaman, Immanuel; Feng, Jian; Golden, Sam A; Aleyasin, Hossein; Lorsch, Zachary S; Cates, Hannah M; Flanigan, Meghan E; Menard, Caroline; Heshmati, Mitra; Wang, Zichen; Ma'ayan, Avi; Shen, Li; Hodes, Georgia E; Russo, Scott J

2016-01-01

Adult women are twice as likely as men to suffer from affective and anxiety disorders, although the mechanisms underlying heightened female stress susceptibility are incompletely understood. Recent findings in mouse Nucleus Accumbens (NAc) suggest a role for DNA methylation-driven sex differences in genome-wide transcriptional profiles. However, the role of another epigenetic process-microRNA (miR) regulation-has yet to be explored. We exposed male and female mice to Subchronic Variable Stress (SCVS), a stress paradigm that produces depression-like behavior in female, but not male, mice, and performed next generation mRNA and miR sequencing on NAc tissue. We applied a combination of differential expression, miR-mRNA network and functional enrichment analyses to characterize the transcriptional and post-transcriptional landscape of sex differences in NAc stress response. We find that male and female mice exhibit largely non-overlapping miR and mRNA profiles following SCVS. The two sexes also show enrichment of different molecular pathways and functions. Collectively, our results suggest that males and females mount fundamentally different transcriptional and post-transcriptional responses to SCVS and engage sex-specific molecular processes following stress. These findings have implications for the pathophysiology and treatment of stress-related disorders in women.

Sex Differences in Proximal Control of the Knee Joint

PubMed Central

Mendiguchia, Jurdan; Ford, Kevin R.; Quatman, Carmen E.; Alentorn-Geli, Eduard; Hewett, Timothy E.

2014-01-01

Following the onset of maturation, female athletes have a significantly higher risk for anterior cruciate ligament (ACL) injury compared with male athletes. While multiple sex differences in lower-extremity neuromuscular control and biomechanics have been identified as potential risk factors for ACL injury in females, the majority of these studies have focused specifically on the knee joint. However, increasing evidence in the literature indicates that lumbopelvic (core) control may have a large effect on knee-joint control and injury risk. This review examines the published evidence on the contributions of the trunk and hip to knee-joint control. Specifically, the sex differences in potential proximal controllers of the knee as risk factors for ACL injury are identified and discussed. Sex differences in trunk and hip biomechanics have been identified in all planes of motion (sagittal, coronal and transverse). Essentially, female athletes show greater lateral trunk displacement, altered trunk and hip flexion angles, greater ranges of trunk motion, and increased hip adduction and internal rotation during sport manoeuvres, compared with their male counterparts. These differences may increase the risk of ACL injury among female athletes. Prevention programmes targeted towards trunk and hip neuromuscular control may decrease the risk for ACL injuries. PMID:21688868

Infant sex-specific placental cadmium and DNA methylation associations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohanty, April F., E-mail: april.mohanty@va.gov; Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA; Farin, Fred M., E-mail: freddy@u.washington.edu

Background: Recent evidence suggests that maternal cadmium (Cd) burden and fetal growth associations may vary by fetal sex. However, mechanisms contributing to these differences are unknown. Objectives: Among 24 maternal-infant pairs, we investigated infant sex-specific associations between placental Cd and placental genome-wide DNA methylation. Methods: We used ANOVA models to examine sex-stratified associations of placental Cd (dichotomized into high/low Cd using sex-specific Cd median cutoffs) with DNA methylation at each cytosine-phosphate-guanine site or region. Statistical significance was defined using a false discovery rate cutoff (<0.10). Results: Medians of placental Cd among females and males were 5 and 2 ng/g, respectively.more » Among females, three sites (near ADP-ribosylation factor-like 9 (ARL9), siah E3 ubiquitin protein ligase family member 3 (SIAH3), and heparin sulfate (glucosamine) 3-O-sulfotransferase 4 (HS3ST4) and one region on chromosome 7 (including carnitine O-octanoyltransferase (CROT) and TP5S target 1 (TP53TG1)) were hypomethylated in high Cd placentas. Among males, high placental Cd was associated with methylation of three sites, two (hypomethylated) near MDS1 and EVI1 complex locus (MECOM) and one (hypermethylated) near spalt-like transcription factor 1 (SALL1), and two regions (both hypomethylated, one on chromosome 3 including MECOM and another on chromosome 8 including rho guanine nucleotide exchange factor (GEF) 10 (ARHGEF10). Differentially methylated sites were at or close to transcription start sites of genes involved in cell damage response (SIAH3, HS3ST4, TP53TG1) in females and cell differentiation, angiogenesis and organ development (MECOM, SALL1) in males. Conclusions: Our preliminary study supports infant sex-specific placental Cd-DNA methylation associations, possibly accounting for previously reported differences in Cd-fetal growth associations across fetal sex. Larger studies are needed to replicate and extend these findings. Such investigations may further our understanding of epigenetic mechanisms underlying maternal Cd burden with suboptimal fetal growth associations. - Highlights: • We examine sex-specific placental-Cd and -genome-wide DNA methylation associations. • In females, associated sites were at/near genes involved in cell damage response. • In males, associated sites were at/near angiogenesis and organ development genes. • Our study supports infant sex-specific placental Cd-DNA methylation associations.« less

Sex-specific differences in the severity of symptoms and recovery rate following sports-related concussion in young athletes.

PubMed

Berz, Kate; Divine, Jon; Foss, Kim Barber; Heyl, Rachel; Ford, Kevin R; Myer, Gregory D

2013-05-01

While research on adult recovery from concussion indicates sex-specific symptoms and recovery rates, there is little existing data on younger patient populations. To determine sex-specific differences in the severity of presenting symptoms and recovery rate between groups of young athletes who presented ≤ 7 or > 7 days after sports-related concussion. This study was a retrospective review of athletes aged 9 to 17 years who were referred for evaluation of a sports-related concussion over a 24-month period. The study groups were divided by sex and post-injury presentation to the clinic at ≤ 7 days and > 7 days from the date of injury. Athletes with learning disabilities were excluded from the study and data analysis. Age, height, and weight were recorded for each subject. Each subject also reported their initial degree of confusion, amnesia, or loss of consciousness, and whether a helmet was worn when the injury was sustained. A 22-item post-concussion symptom score (SS) scale was completed by both groups on initial assessment (SS1) and follow-up visit (SS2). The recovery rate (SSR) was calculated as (SS2-SS1)/days between SS2 and SS1. Sex and group comparisons for SS1 and SSR were performed using 2 × 2 analysis of variance. A similar analysis was also performed for effects of sex on SS1 and SSR in patients who were not wearing a helmet. Thirty-seven athletes aged 15.0 ± 1.9 years were evaluated. Males, regardless of day of presentation, had a lower SS1 evaluation than females (15.8 vs 30.9; P < 0.05). Males without helmets did not differ from females without helmets, but this was not significantly different (14.1 vs 29.6; P = 0.1). There was not a significant difference in SS1 evaluation between the groups who presented at ≤ 7 or > 7 days. The overall mean SSR was -1.2/day, with no significant difference seen between groups or sex. There were no significant differences in degree of loss of consciousness, amnesia, confusion, or age between the sexes or groups. Whether presenting at ≤ 7 or > 7 days following a sports-related concussion, female athletes reported a higher SS1 evaluation. With SSR being similar between sexes, the current data suggest that young, female athletes may take longer to become symptom free following sports-related concussion. This information may be an important factor in returning a young athlete to sport after sports-related concussion.

Sex-specific lateralization of event-related potential effects during mental rotation of polygons.

PubMed

Pellkofer, Julia; Jansen, Petra; Heil, Martin

2014-08-06

Mental rotation performance has been found to produce one of the largest sex differences in cognition. Many theories suggest that this effect should be accompanied by a sex difference in functional cerebral asymmetry, but empirical data are more than equivocal probably because of (a) the use of inappropriate stimuli and (b) insufficient power of most neurophysiological studies. Therefore, sex differences in mental rotation of polygons were investigated in 122 adults. Men outperformed women on mental rotation speed (as well as on response time and accuracy). On the basis of the electrophysiological brain correlates of mental rotation, we observed a bilateral brain activity for men, whereas women's brain activity was clearly lateralized toward the left hemisphere if and only if mental rotation was involved. Thus, sex differences in functional cerebral asymmetry can indeed be observed if appropriate stimuli are used in a sufficiently large sample.

Sex differences in the adolescent brain and body: Findings from the saguenay youth study.

PubMed

Paus, Tomáš; Wong, Angelita Pui-Yee; Syme, Catriona; Pausova, Zdenka

2017-01-02

This Mini-Review describes sex differences in 66 quantitative characteristics of the brain and body measured in a community-based sample of 1,024 adolescents 12-18 years of age, members of the Saguenay Youth Study. Using an extensive phenotyping protocol, we have obtained measures in a number of domains, including brain structure, cognition, mental health, substance use, body composition, metabolism, cardiovascular reactivity, and life style. For each measure, we provide estimates of effect size (Cohen's d) and sex-specific correlations with age (Pearson R). In total 59 of the 66 characteristics showed sex differences (at a nominal P < 0.05), with small (32), medium-sized (13), and large (11) effects. Some, but not all, of these sex differences increase during adolescence; this appears to be the case mostly for anatomical and physiological measures. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Age and sex differences in ranges of motion and motion patterns.

PubMed

Hwang, Jaejin; Jung, Myung-Chul

2015-01-01

This study investigated the effects of age and sex on joint ranges of motion (ROMs) and motion patterns. Forty participants performed 18 motions using eight body segments at self-selected speeds. Older subjects showed smaller ROMs than younger subjects for 11 motions; the greatest difference in ROM was 44.9% for eversion/inversion of the foot. Older subjects also required more time than younger subjects to approach the peak angular velocity for six motions. In contrast, sex significantly affected ROMs but not motion patterns. Male subjects exhibited smaller ROMs than female subjects for four motions; the greatest sex-dependent difference in ROM was 29.7% for ulnar/radial deviation of the hand. The age and sex effects depended on the specific segments used and motions performed, possibly because of differences in anatomical structures and frequencies of use of the joints in habitual physical activities between the groups.

Chemical communication in termites: syn-4,6-dimethylundecan-1-ol as trail-following pheromone, syn-4,6-dimethylundecanal and (5E)-2,6,10-trimethylundeca-5,9-dienal as the respective male and female sex pheromones in Hodotermopsis sjoestedti (Isoptera, Archotermopsidae).

PubMed

Lacey, Michael J; Sémon, Etienne; Krasulová, Jana; Sillam-Dussès, David; Robert, Alain; Cornette, Richard; Hoskovec, Michal; Záček, Petr; Valterová, Irena; Bordereau, Christian

2011-12-01

The trail-following pheromone and sex pheromones were investigated in the Indomalayan termite Hodotermopsis sjoestedti belonging to the new family Archotermopsidae. Gas chromatography coupled to mass spectrometry (GC-MS) after solid phase microextraction (SPME) of the sternal gland secretion of pseudergates and trail-following bioassays demonstrated that the trail-following pheromone of H. sjoestedti was syn-4,6-dimethylundecan-1-ol, a new chemical structure for termite pheromones. GC-MS after SPME of the sternal gland secretion of alates also allowed the identification of sex-specific compounds. In female alates, the major sex-specific compound was identified as (5E)-2,6,10-trimethylundeca-5,9-dienal, a compound previously identified as the female sex pheromone of the termite Zootermopsis nevadensis. In male alates, the major sex-specific compound was identified as syn-4,6-dimethylundecanal, a homolog of syn-4,6-dimethyldodecanal, which has previously been confirmed as the male sex pheromone of Z. nevadensis. The presence of sex-specific compounds in alates of H. sjoestedti strongly suggests for this termite the presence of sex-specific pairing pheromones which were only known until now in Z. nevadensis. Our results showed therefore a close chemical relationship between the pheromones of the taxa Hodotermopsis and Zootermopsis and, in contrast, a clear difference with the taxa Stolotermes and Porotermes, which is in total agreement with the recent creation of the families Archotermopsidae and Stolotermitidae as a substitute for the former family Termopsidae. Copyright © 2011 Elsevier Ltd. All rights reserved.

The influence of sex-linked genetic mechanisms on attention and impulsivity

PubMed Central

Trent, Simon; Davies, William

2012-01-01

It is now generally agreed that there are inherent sex differences in healthy individuals across a number of neurobiological domains (including brain structure, neurochemistry, and cognition). Moreover, there is a burgeoning body of evidence highlighting sex differences within neuropsychiatric populations (in terms of the rates of incidence, clinical features/progression, neurobiology and pathology). Here, we consider the extent to which attention and impulsivity are sexually dimorphic in healthy populations and the extent to which sex might modulate the expression of disorders characterised by abnormalities in attention and/or impulsivity such as attention deficit hyperactivity disorder (ADHD), autism and addiction. We then discuss general genetic mechanisms that might underlie sex differences in attention and impulsivity before focussing on specific positional and functional candidate sex-linked genes that are likely to influence these cognitive processes. Identifying novel sex-modulated molecular targets should ultimately enable us to develop more effective therapies in disorders associated with attentional/impulsive dysfunction. PMID:21983394

[Pain medicine from intercultural and gender-related perspectives].

PubMed

Schiltenwolf, M; Pogatzki-Zahn, E M

2015-10-01

Cultural setting and sex and gender of the patient are important factors affecting the occurrence, severity, clinical course and prognosis of pain and pain-related diseases. Intercultural differences in the perception and verbal expression of symptoms and emotional function are fundamental and it is important to realize these differences in order to understand patients with a migration background. A trusting doctor-patient relationship is generally very sensitive and it is even more difficult to establish when differences in the cultural background impair mutual understanding. Regarding sex and gender there is evidence that females are more susceptible to developing chronic pain conditions, experience more severe pain and respond differently to pain therapy; however, results of recent studies indicate that females are not that different to males when comparing several modalities of experimental pain (although some differences exist). Similarly, sex and gender differences in postoperative pain seem to exist but the differences are relatively small when pain scores are compared. Other aspects, such as the response to analgesics and role of psychosocial factors should be addressed when sex and gender aspects are studied. Similarly, sex and gender differences in the prevalence of chronic pain exist but the results of some studies, e.g. those controlling for confounders, are not very clear. Research is needed to delineate the role of specific aspects affecting sex and gender differences and the underlying mechanisms (e.g. reduced inhibitory control, hormones, psychological aspects and social factors). Altogether, we need to open our minds to some intercultural and sex and gender aspects in the clinical setting. For sex and gender differences we may need a more biopsychosocial approach to understand the underlying differences and differentiate between sex and gender and sex and gender-associated aspects for acute and chronic pain.

Effects of Sex and Gender on Adaptation to Space: Neurosensory Systems

PubMed Central

Cohen, Helen S.; Cerisano, Jody M.; Clayton, Janine A.; Cromwell, Ronita; Danielson, Richard W.; Hwang, Emma Y.; Tingen, Candace; Allen, John R.; Tomko, David L.

2014-01-01

Abstract Sex and gender differences have long been a research topic of interest, yet few studies have explored the specific differences in neurological responses between men and women during and after spaceflight. Knowledge in this field is limited due to the significant disproportion of sexes enrolled in the astronaut corps. Research indicates that general neurological and sensory differences exist between the sexes, such as those in laterality of amygdala activity, sensitivity and discrimination in vision processing, and neuronal cell death (apoptosis) pathways. In spaceflight, sex differences may include a higher incidence of entry and space motion sickness and of post-flight vestibular instability in female as opposed to male astronauts who flew on both short- and long-duration missions. Hearing and auditory function in crewmembers shows the expected hearing threshold differences between men and women, in which female astronauts exhibit better hearing thresholds. Longitudinal observations of hearing thresholds for crewmembers yield normal age-related decrements; however, no evidence of sex-related differences from spaceflight has been observed. The impact of sex and gender differences should be studied by making spaceflight accessible and flying more women into space. Only in this way will we know if increasingly longer-duration missions cause significantly different neurophysiological responses in men and women. PMID:25401941

Individual and Sex Differences in the Consequences of Victimization: Moderation by Approach and Avoidance Motivation

ERIC Educational Resources Information Center

Llewellyn, Nicole; Rudolph, Karen D.

2014-01-01

Peer victimization is a known risk factor for various forms of maladjustment; however, the specific type of maladjustment may depend on individual differences in youth. This 2-wave longitudinal study examined the hypothesis that social approach-avoidance motivation, together with sex, would moderate the contribution of 3rd-grade victimization to…

Parent-Toddler Play with Feminine Toys: Are All Dolls the Same?

ERIC Educational Resources Information Center

Caldera, Yvonne M.; Sciaraffa, Mary A.

1998-01-01

Studies specific play behaviors of parents and toddlers when playing with baby dolls and a clown as indices of gender-role socialization by parents. The clown and dolls elicited different play behaviors from both the parents and toddlers. Same sex parent/toddler dyads engaged in different types of play from opposite-sex dyads. (MMU)

Liver phospholipids fatty acids composition in response to different types of diets in rats of both sexes.

PubMed

Ranković, Slavica; Popović, Tamara; Martačić, Jasmina Debeljak; Petrović, Snježana; Tomić, Mirko; Ignjatović, Đurđica; Tovilović-Kovačević, Gordana; Glibetić, Maria

2017-05-19

Dietary intake influence changes in fatty acids (FA) profiles in liver which plays a central role in fatty acid metabolism, triacylglycerol synthesis and energy homeostasis. We investigated the effects of 4-weeks treatment with milk- and fish-based diet, on plasma biochemical parameters and FA composition of liver phospholipids (PL) in rats of both sexes. Adult, 4 months old, Wistar rats of both sexes, were fed with different types of diets: standard, milk-based and fish-based, during 4 weeks. Analytical characterization of different foods was done. Biochemical parameters in plasma were determined. Fatty acid composition was analyzed by gas-chromatography. Statistical significance of FA levels was tested with two-way analysis of variance (ANOVA) using the sex of animals and treatment (type of diet) as factors on logarithmic or trigonometric transformed data. Our results showed that both, milk- and fish-based diet, changed the composition and ratio of rat liver phospholipids FA, in gender-specific manner. Initially present sex differences appear to be dietary modulated. Although, applied diets changed the ratio of total saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA), and effects were gender specific. Milk-based diet lowered SFA and elevated MUFA in males and increased PUFA in females vs. standard diet. The same diet decreased n-3, increased n-6 and n-6/n-3 ratio in males. Fish-based diet increased n-3, decreased n-6 and n-6/n-3 ratio vs. standard and milk-based diet in females. However, the ratio of individual FA in liver PL was also dietary-influenced, but with gender specific manner. While in females fish-based diet decreased AA (arachidonic acid) increased level of EPA (eicosapentaenoic acid), DPA (docosapentaenoic acid) and DHA (docosahexaenoic acid), the same diet elevated only DHA levels in males. Gender related variations in FA composition of rat liver PL were observed, and results have shown that those initial differences could be significantly modulated by the type of diet. Furthermore, the modulatory effects of milk- and fish-based diets on liver phospholipids FA profiles appeared to be sex-specific.

Grammatical gender and inferences about biological properties in german-speaking children.

PubMed

Saalbach, Henrik; Imai, Mutsumi; Schalk, Lennart

2012-01-01

In German, nouns are assigned to one of the three gender classes. For most animal names, however, the assignment is independent of the referent's biological sex. We examined whether German-speaking children understand this independence of grammar from semantics or whether they assume that grammatical gender is mapped onto biological sex when drawing inferences about sex-specific biological properties of animals. Two cross-linguistic studies comparing German-speaking and Japanese-speaking preschoolers were conducted. The results suggest that German-speaking children utilize grammatical gender as a cue for inferences about sex-specific properties of animals. Further, we found that Japanese- and German-speaking children recruit different resources when drawing inferences about sex-specific properties: Whereas Japanese children paralleled their pattern of inference about properties common to all animals, German children relied on the grammatical gender class of the animal. Implications of these findings for studying the relation between language and thought are discussed. Copyright © 2012 Cognitive Science Society, Inc.

Sex-specific differences in cardiac control and hematology of sockeye salmon (Oncorhynchus nerka) approaching their spawning grounds.

PubMed

Sandblom, Erik; Clark, Timothy D; Hinch, Scott G; Farrell, Anthony P

2009-10-01

Some male salmonids (e.g., rainbow trout) display profound cardiovascular adjustments during sexual maturation, including cardiac growth and hypertension, and tachycardia has been observed in free-ranging male salmonids near their spawning grounds. In the present study, we investigated cardiac control, dorsal aortic blood pressure, cardiac morphometrics, and hematological variables in wild, sexually maturing sockeye salmon (Oncorhynchus nerka) with a particular aim to decipher any sex-specific differences. Routine heart rate (f(H)) was significantly higher in females (52 vs. 43 beats/min), which was due to significantly lower cholinergic tone (28 vs. 46%), because there were no differences in adrenergic tone or intrinsic heart rate between sexes. No differences in blood pressure were observed despite males possessing an 11% greater relative ventricular mass. Concomitant with higher routine heart rates, female sockeye had significantly higher levels of cortisol, testosterone, and 17beta-estradiol, whereas the level of 11-ketotestosterone was higher in males. There were no differences in hematocrit or hemoglobin concentration between the sexes. The findings of this study highlight the importance of considering sex as a variable in research fields such as conservation biology and when modeling the consequences of local and global climate change. Indeed, this study helps to provide a mechanistic basis for the significantly higher rates of female mortality observed in previous studies of wild-caught sockeye salmon.

Sex-specific differences in mitochondria biogenesis, morphology, respiratory function, and ROS homeostasis in young mouse heart and brain.

PubMed

Khalifa, Abdel Rahman M; Abdel-Rahman, Engy A; Mahmoud, Ali M; Ali, Mohamed H; Noureldin, Maha; Saber, Saber H; Mohsen, Mahmoud; Ali, Sameh S

2017-03-01

Sex-specific differences in mitochondrial function and free radical homeostasis are reported in the context of aging but not well-established in pathogeneses occurring early in life. Here, we examine if sex disparity in mitochondria function, morphology, and redox status starts early and hence can be implicated in sexual dimorphism in cardiac as well as neurological disorders prevalent at young age. Although mitochondrial activity in the heart did not significantly vary between sexes, female brain exhibited enhanced respiration and higher reserve capacity. This was associated with lower H 2 O 2 production in female cardiac and brain tissues. Using transmission electron microscopy, we found that the number of female cardiac mitochondria is moderately greater (117 ± 3%, P  = 0.049, N  = 4) than male's, which increased significantly for cortical mitochondria (134 ± 4%, P  = 0.001, N  = 4). However, male's cardiac mitochondria exhibited fragmented, circular, and smaller mitochondria relative to female's mitochondria, while no morphologic sex-dependent differences were observed in cortical mitochondria. No sex differences were detected in Nox2 and Nox4 proteins or O 2 -consuming/H 2 O 2 -producing activities in brain homogenate or synaptosomes. However, a strong trend of increased EPR-detected NOX superoxide in male synaptosomes hinted at higher superoxide dismutase activity in female brains, which was confirmed by two independent protocols. We also provide direct evidence that respiring mitochondria generally produce an order-of-magnitude lower reactive oxygen species (ROS) proportions than currently estimated. Our results indicate that sex differences in mitochondrial biogenesis, bioenergetics, and morphology may start at young age and that sex-dependent SOD capacity may be responsible for differences in ROS homeostasis in heart and brain. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

The Sex and Race Specific Relationship between Anthropometry and Body Fat Composition Determined from Computed Tomography: Evidence from the Multi-Ethnic Study of Atherosclerosis.

PubMed

Mongraw-Chaffin, Morgana; Golden, Sherita Hill; Allison, Matthew A; Ding, Jingzhong; Ouyang, Pamela; Schreiner, Pamela J; Szklo, Moyses; Woodward, Mark; Young, Jeffery Hunter; Anderson, Cheryl A M

2015-01-01

Few studies have investigated the relationship of anthropometric measurements with computed tomography (CT) body fat composition, and even fewer determined if these relationships differ by sex and race. CT scans from 1,851 participants in the population based Multi-Ethnic Study of Atherosclerosis were assessed for visceral and subcutaneous fat areas by semi-automated segmentation of body compartments. Regression models were used to investigate relationships for anthropometry with visceral and subcutaneous fat separately by sex and race/ethnicity. Participants were 50% female, 41% Caucasian, 13% Asian, 21% African American, and 25% Hispanic. For visceral fat, the positive relationship with weight (p = 0.028), waist circumference (p<0.001), waist to hip ratio (p<0.001), and waist to height ratio (p = 0.05) differed by sex, with a steeper slope for men. That is, across the range of these anthropometric measures the rise in visceral fat is faster for men than for women. Additionally, there were differences by race/ethnicity in the relationship with height (p<0.001), weight (p<0.001), waist circumference (p<0.001), hip circumference (p = 0.006), and waist to hip ratio (p = 0.001) with the Hispanic group having shallower slopes. For subcutaneous fat, interaction by sex was found for all anthropometric indices at p<0.05, but not for race/ethnicity. The relationship between anthropometry and underlying adiposity differs by sex and race/ethnicity. When anthropometry is used as a proxy for visceral fat in research, sex-specific models should be used.

The Sex and Race Specific Relationship between Anthropometry and Body Fat Composition Determined from Computed Tomography: Evidence from the Multi-Ethnic Study of Atherosclerosis

PubMed Central

Mongraw-Chaffin, Morgana; Golden, Sherita Hill; Allison, Matthew A.; Ding, Jingzhong; Ouyang, Pamela; Schreiner, Pamela J.; Szklo, Moyses; Woodward, Mark; Young, Jeffery Hunter; Anderson, Cheryl A. M.

2015-01-01

Background Few studies have investigated the relationship of anthropometric measurements with computed tomography (CT) body fat composition, and even fewer determined if these relationships differ by sex and race. Methods CT scans from 1,851 participants in the population based Multi-Ethnic Study of Atherosclerosis were assessed for visceral and subcutaneous fat areas by semi-automated segmentation of body compartments. Regression models were used to investigate relationships for anthropometry with visceral and subcutaneous fat separately by sex and race/ethnicity. Results Participants were 50% female, 41% Caucasian, 13% Asian, 21% African American, and 25% Hispanic. For visceral fat, the positive relationship with weight (p = 0.028), waist circumference (p<0.001), waist to hip ratio (p<0.001), and waist to height ratio (p = 0.05) differed by sex, with a steeper slope for men. That is, across the range of these anthropometric measures the rise in visceral fat is faster for men than for women. Additionally, there were differences by race/ethnicity in the relationship with height (p<0.001), weight (p<0.001), waist circumference (p<0.001), hip circumference (p = 0.006), and waist to hip ratio (p = 0.001) with the Hispanic group having shallower slopes. For subcutaneous fat, interaction by sex was found for all anthropometric indices at p<0.05, but not for race/ethnicity. Conclusion The relationship between anthropometry and underlying adiposity differs by sex and race/ethnicity. When anthropometry is used as a proxy for visceral fat in research, sex-specific models should be used. PMID:26448048

Sex differences in visual attention to erotic and non-erotic stimuli.

PubMed

Lykins, Amy D; Meana, Marta; Strauss, Gregory P

2008-04-01

It has been suggested that sex differences in the processing of erotic material (e.g., memory, genital arousal, brain activation patterns) may also be reflected by differential attention to visual cues in erotic material. To test this hypothesis, we presented 20 heterosexual men and 20 heterosexual women with erotic and non-erotic images of heterosexual couples and tracked their eye movements during scene presentation. Results supported previous findings that erotic and non-erotic information was visually processed in a different manner by both men and women. Men looked at opposite sex figures significantly longer than did women, and women looked at same sex figures significantly longer than did men. Within-sex analyses suggested that men had a strong visual attention preference for opposite sex figures as compared to same sex figures, whereas women appeared to disperse their attention evenly between opposite and same sex figures. These differences, however, were not limited to erotic images but evidenced in non-erotic images as well. No significant sex differences were found for attention to the contextual region of the scenes. Results were interpreted as potentially supportive of recent studies showing a greater non-specificity of sexual arousal in women. This interpretation assumes there is an erotic valence to images of the sex to which one orients, even when the image is not explicitly erotic. It also assumes a relationship between visual attention and erotic valence.

Long-Term Impact of Intrauterine Neuroinflammation and Treatment with Magnesium Sulphate and Betamethasone: Sex-Specific Differences in a Preterm Labor Murine Model

DTIC Science & Technology

2017-12-20

offspring per litter assessed on post -natal day S with the exception of PBS vs. PBS+ MgS04/betamethasone control groups (student’s t- test P<O.OS... Design Timed pregnant CD1 mice - surgeries on E17.5 I I -----------------------------------1 1 Intrauterine injection 1 t t PBS LPS .- -----J...experimental adult animals and if there is a sex-specific difference in their response has not been tested . Based on the above, we hypothesize that

Sex-specific differences in corticosterone secretion, behavioral phenotypes and expression of TrkB.T1 and TrkB.FL receptor isoforms: Impact of systemic TrkB inhibition and combinatory stress exposure in adolescence.

PubMed

Azogu, Idu; Liang, Jacky; Plamondon, Helene

2018-05-09

Stress exposure has been implicated in the development of mood disorders, although little is known about the lasting effects of repeated stress during the adolescent period on sex-specific differences in endocrine and plasticity-signaling responses in adulthood. Using a 10-day combinatory stress paradigm (postnatal day (PND) 26 to 35), we examined sex-specific impact of adolescent stress and inhibition of tyrosine-related kinase B (TrkB) receptor (ANA-12; 0.5 mg/kg, i.p.) on 1) adolescent blood corticosterone levels, 2) adult locomotion and anxiety-like behavior, and 3) region-specific differences in endogenous TrkB full-length (TrkB.FL) and truncated (TrkB.T1) receptor isoforms. Blood collected on days 1, 5 and 10 revealed elevated basal and stress-induced CORT secretion in females compared to males, while ANA-12 attenuated CORT elevations post stress in both sexes. As adults, all females exhibited higher locomotor and exploratory activity than males in the open field test and elevated plus maze, and differences were comparable in the forced swim within stress-naïve and stress groups. Biochemically, vehicle-treated males showed elevated TrkB.T1 and TrkB.FL compared to vehicle-treated females in the PFC, hippocampus and NAc, and levels were consistently attenuated by ANA-12 treatment in non-stress males. With regards to stress exposure, expression of both isoforms was strongly down-regulated in the NAc of males only and was associated with increased TrkB.T1 in the PFC. ANA-12 enhanced expression in females, independent of stress exposure, compared to vehicle-treated counterparts, expression being increased for TrkB.T1 versus TrkB.FL and magnitude of the changes being region-specific. In contrast, ANA-12 effects in stressed males were restricted to inhibition of both isoforms in the hippocampus. Together, our findings support that TrkB activation, contingent on stress exposure, differentially affects TrkB isoform regulation during adulthood. Sex-specific biochemical responses at delayed intervals following adolescent stress exposure further support the need to include the sex variable in animal models. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

Sex differences in the effects of juvenile and adult diet on age-dependent reproductive effort.

PubMed

Houslay, T M; Hunt, J; Tinsley, M C; Bussière, L F

2015-05-01

Sexual selection should cause sex differences in patterns of resource allocation. When current and future reproductive effort trade off, variation in resource acquisition might further cause sex differences in age-dependent investment, or in sensitivity to changes in resource availability over time. However, the nature and prevalence of sex differences in age-dependent investment remain unclear. We manipulated resource acquisition at juvenile and adult stages in decorated crickets, Gryllodes sigillatus, and assessed effects on sex-specific allocation to age-dependent reproductive effort (calling in males, fecundity in females) and longevity. We predicted that the resource and time demands of egg production would result in relatively consistent female strategies across treatments, whereas male investment should depend sharply on diet. Contrary to expectations, female age-dependent reproductive effort diverged substantially across treatments, with resource-limited females showing much lower and later investment in reproduction; the highest fecundity was associated with intermediate lifespans. In contrast, long-lived males always signalled more than short-lived males, and male age-dependent reproductive effort did not depend on diet. We found consistently positive covariance between male reproductive effort and lifespan, whereas diet altered this covariance in females, revealing sex differences in the benefits of allocation to longevity. Our results support sex-specific selection on allocation patterns, but also suggest a simpler alternative: males may use social feedback to make allocation decisions and preferentially store resources as energetic reserves in its absence. Increased calling effort with age therefore could be caused by gradual resource accumulation, heightened mortality risk over time, and a lack of feedback from available mates. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Sex Differences in Human Fatigability: Mechanisms and Insight to Physiological Responses

PubMed Central

Hunter, Sandra K.

2014-01-01

Sex-related differences in physiology and anatomy are responsible for profound differences in neuromuscular performance and fatigability between men and women. Women are usually less fatigable than men for similar intensity isometric fatiguing contractions. This sex difference in fatigability, however, is task specific because different neuromuscular sites will be stressed when the requirements of the task are altered, and the stress on these sites can differ for men and women. Task variables that can alter the sex difference in fatigue include the type, intensity and speed of contraction, the muscle group assessed, and the environmental conditions. Physiological mechanisms that are responsible for sex-based differences in fatigability may include activation of the motor neuron pool from cortical and subcortical regions, synaptic inputs to the motor neuron pool via activation of metabolically-sensitive small afferent fibres in the muscle, muscle perfusion, and skeletal muscle metabolism and fibre type properties. Non-physiological factors such as the sex bias of studying more males than females in human and animal experiments can also mask a true understanding of the magnitude and mechanisms of sex-based differences in physiology and fatigability. Despite recent developments, there is a tremendous lack of understanding of sex differences in neuromuscular function and fatigability, the prevailing mechanisms and the functional consequences. This review emphasises the need to understand sex-based differences in fatigability in order to shed light on the benefits and limitations that fatigability can exert for men and women during daily tasks, exercise performance, training and rehabilitation in both health and disease. PMID:24433272

Adenoma Detection Rates for Screening Colonoscopies in Smokers and Obese Adults: Data From the New Hampshire Colonoscopy Registry.

PubMed

Anderson, Joseph C; Weiss, Julia E; Robinson, Christina M; Butterly, Lynn F

To examine screening adenoma detection rates (ADR) and serrated detection rates (SDR) among smokers and obese adults in the New Hampshire Colonoscopy Registry. ADR, a quality measure for screening colonoscopies, is associated with protection from interval colorectal cancer. Currently, only sex-specific ADR benchmarks are reported. However, obesity and smoking ≥20 pack-years are strong predictors for colorectal neoplasia, as highlighted by the 2009 American College of Gastroenterology CRC Screening Guidelines. Data comparing ADR in smokers and obese adults to those without these risks are limited. We calculated ADR, SDR, and 95% confidence intervals for screening colonoscopies in participants ≥50 years. Sex-specific and sex-age-specific rates were compared by smoking exposure (never vs. <20 vs. ≥20 pack-years) and body mass index (<30 vs. ≥30). A total of 21,539 screening colonoscopies were performed by 77 endoscopists at 20 facilities (April 2009 to September 2013). The difference in ADR between nonsmokers and smokers with ≥20 pack-years was 8.8% (P<0.0001) and between obesity groups 5.0% (P<0.0001). Significant sex-specific and sex-age-specific increases in ADR and SDR were found among smokers and obese participants. ADR and SDR for smokers and obese adults were significantly higher than their counterparts without those risks. Endoscopists should consider the prevalence of these risks within their screening population when comparing their rates to established benchmarks. Calculating sex-specific or sex-age-specific ADR and SDR based on smoking and obesity may provide optimal protection for populations with a particularly high prevalence of smokers and obese adults.

Numerous Transitions of Sex Chromosomes in Diptera

PubMed Central

Vicoso, Beatriz; Bachtrog, Doris

2015-01-01

Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot), but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes). Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa. PMID:25879221

Sex and Exercise Interact to Alter the Expression of Anabolic Androgenic Steroid-Induced Anxiety-Like Behaviors in the Mouse

PubMed Central

Onakomaiya, Marie M.; Porter, Donna M.; Oberlander, Joseph G.; Henderson, Leslie P.

2014-01-01

Anabolic androgenic steroids (AAS) are taken by both sexes to enhance athletic performance and body image, nearly always in conjunction with an exercise regime. Although taken to improve physical attributes, chronic AAS use can promote negative behavior, including anxiety. Few studies have directly compared the impact of AAS use in males versus females or assessed the interaction of exercise and AAS. We show that AAS increase anxiety-like behaviors in female but not male mice and that voluntary exercise accentuates these sex-specific differences. We also show that levels of the anxiogenic peptide corticotrophin releasing factor (CRF) are significantly greater in males, but that AAS selectively increase CRF levels in females, thus abrogating this sex-specific difference. Exercise did not ameliorate AAS-induced anxiety or alter CRF levels in females. Exercise was anxiolytic in males, but this behavioral outcome did not correlate with CRF levels. Brain-derived neurotrophic factor (BDNF) has also been implicated in the expression of anxiety. As with CRF, levels of hippocampal BDNF mRNA were significantly greater in males than females. AAS and exercise were without effect on BDNF mRNA in females. In males, anxiolytic effects of exercise correlated with increased BDNF mRNA, however AAS-induced changes in BDNF mRNA and anxiety did not. In sum, we find that AAS elicit sex-specific differences in anxiety and that voluntary exercise accentuates these differences. In addition, our data suggest that these behavioral outcomes may reflect convergent actions of AAS and exercise on a sexually differentiated CRF signaling system within the extended amygdala. PMID:24768711

Sex Differences in Brain-Derived Neurotrophic Factor Signaling and Functions

PubMed Central

Chan, Chi Bun; Ye, Keqiang

2016-01-01

Brain derived neurotrophic factor (BDNF) is a member of the neurotrophin family that plays a critical role in numerous neuronal activities. Recent studies report that some functions or action mechanisms of BDNF vary in a sex-dependent manner. In particular, BDNF content in some brain parts and the tendency of developing BDNF-deficient-related diseases like depression is higher in female animals. With the support of other relevant studies, it is suggested that sex hormones or steroids can modulate the activities of BDNF, which may account for its functional discrepancy in different sexes. Indeed, the cross-talk between BDNF and sex steroids has been detected for decades and some sex steroids like estrogen have a positive regulatory effect to BDNF expression and signaling. Thus, the sex of animal models used is critical when studying the functions of BDNF in vivo. In this review, we will summarize our current findings on the difference in expression, signaling, and functions of BDNF between sexes. We will also discuss the potential mechanisms in mediating these differential responses with a specific emphasis on sex steroids. By presenting and discussing these findings, we encourage taking sex influences into consideration when designing experiments, interpreting results and drawing conclusions. PMID:27870419

Toward a Molecular Understanding of Noise-Induced Hearing Loss

DTIC Science & Technology

2017-10-01

cell, SAHA, Heat shock, sex differences 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON...threshold shift, Temporary threshold shift, Noise induced hearing loss, Ribotag, RNA-seq, Hair cell, Supporting cell, SAHA, Heat shock, Sex ...also sex -specific. TTS-inducing noise exposure: crosses, calibration, validation cytocochleograms, noise exposure, tissue harvesting, polysome IP

Regulation of Estrogen Receptor α Expression in the Hypothalamus by Sex Steroids: Implication in the Regulation of Energy Homeostasis.

PubMed

Liu, Xian; Shi, Haifei

2015-01-01

Sex differences exist in the complex regulation of energy homeostasis that utilizes central and peripheral systems. It is widely accepted that sex steroids, especially estrogens, are important physiological and pathological components in this sex-specific regulation. Estrogens exert their biological functions via estrogen receptors (ERs). ERα, a classic nuclear receptor, contributes to metabolic regulation and sexual behavior more than other ER subtypes. Physiological and molecular studies have identified multiple ERα-rich nuclei in the hypothalamus of the central nervous system (CNS) as sites of actions that mediate effects of estrogens. Much of our understanding of ERα regulation has been obtained using transgenic models such as ERα global or nuclei-specific knockout mice. A fundamental question concerning how ERα is regulated in wild-type animals, including humans, in response to alterations in steroid hormone levels, due to experimental manipulation (i.e., castration and hormone replacement) or physiological stages (i.e., puberty, pregnancy, and menopause), lacks consistent answers. This review discusses how different sex hormones affect ERα expression in the hypothalamus. This information will contribute to the knowledge of estrogen action in the CNS, further our understanding of discrepancies in correlation of altered sex hormone levels with metabolic disturbances when comparing both sexes, and improve health issues in postmenopausal women.

Sex and Gender Differences in the Outcomes of Vaccination over the Life Course.

PubMed

Flanagan, Katie L; Fink, Ashley L; Plebanski, Magdalena; Klein, Sabra L

2017-10-06

Both sex (i.e., biological differences) and gender (i.e., social or cultural influences) impact vaccine acceptance, responses, and outcomes. Clinical data illustrate that among children, young adults, and aged individuals, males and females differ in vaccine-induced immune responses, adverse events, and protection. Although males are more likely to receive vaccines, following vaccination, females typically develop higher antibody responses and report more adverse effects of vaccination than do males. Human, nonhuman animal, and in vitro studies reveal numerous immunological, genetic, hormonal, and environmental factors that differ between males and females and contribute to sex- and gender-specific vaccine responses and outcomes. Herein, we address the impact of sex and gender variables that should be considered in preclinical and clinical studies of vaccines.

Effect of ethnicity and sex on the growth of the axial and appendicular skeleton of children living in a developing country.

PubMed

Nyati, Lukhanyo H; Norris, Shane A; Cameron, Noel; Pettifor, John M

2006-05-01

Bones in the axial and appendicular skeletons exhibit heterogeneous growth patterns between different ethnic and sex groups. However, the influence of this differential growth on the expression of bone mineral content is not yet established. The aims of the present study were to investigate: 1) whether there are ethnic and sex differences in axial and appendicular dimensions of South African children; and 2) whether regional segment length is a better predictor of bone mass than stature. Anthropometric measurements of stature, weight, sitting height, and limb lengths were taken on 368 black and white, male and female 9-year-old children. DXA (dual-energy x-ray absorptiometry) scans of the distal ulna, distal radius, and hip and lumbar spine were also obtained. Analyses of covariance were performed to assess differences in limb lengths, adjusted for differences in stature. Multiple regression analyses were used to assess significant predictors of site-specific bone mass. Stature-adjusted means of limb lengths show that black boys have longer legs and humeri but shorter trunks than white boys. In addition, black children have longer forearms than white children, and girls have longer thighs than boys. The regression analysis demonstrated that site-specific bone mass was more strongly associated with regional segment length than stature, but this had little effect on the overall pattern of ethnic and sex differences. In conclusion, there is a differential effect of ethnicity and sex on the growth of the axial and appendicular skeletons, and regional segment length is a better predictor of site-specific bone mass than stature. Copyright 2005 Wiley-Liss, Inc.

Sex Genotyping of Archival Fixed and Immunolabeled Guinea Pig Cochleas.

PubMed

Depreux, Frédéric F; Czech, Lyubov; Whitlon, Donna S

2018-03-26

For decades, outbred guinea pigs (GP) have been used as research models. Various past research studies using guinea pigs used measures that, unknown at the time, may be sex-dependent, but from which today, archival tissues may be all that remain. We aimed to provide a protocol for sex-typing archival guinea pig tissue, whereby past experiments could be re-evaluated for sex effects. No PCR sex-genotyping protocols existed for GP. We found that published sequence of the GP Sry gene differed from that in two separate GP stocks. We used sequences from other species to deduce PCR primers for Sry. After developing a genomic DNA extraction for archival, fixed, decalcified, immunolabeled, guinea pig cochlear half-turns, we used a multiplex assay (Y-specific Sry; X-specific Dystrophin) to assign sex to tissue as old as 3 years. This procedure should allow reevaluation of prior guinea pig studies in various research areas for the effects of sex on experimental outcomes.

[Sex and gender: Two different scientific domains to be clarified].

PubMed

Fernández, Juan

2010-05-01

Nowadays, the word sex and its related terms (sexual differences, sexual roles and stereotypes), so common not long ago, seems to have been replaced by gender and its related terms (gender differences, gender roles and stereotypes). We can sometimes find both sex and gender sharing the same space in scientific articles, although referring to different domains. In this paper, I try to explain the need for a model that can integrate both of these complex domains of sex and gender, leading to two independent, although complementary, disciplines: Sexology and Genderology. In both cases, I start from a functional standpoint, which will give meaning to both disciplines' specificities, as it is meant to link contributions from different fields of knowledge. This approach can have consequences for research, education, the experience of women, men, and ambiguous individuals, and therapy.

Sex differences in the reciprocal behaviour of children with autism.

PubMed

Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander

2017-08-01

Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in typically developing children (24 girls, 55 boys). While children with autism spectrum disorder showed clear limitations in reciprocal behaviour compared to typically developing children, sex differences were found only in the autism spectrum disorder group: girls with autism spectrum disorder had higher reciprocity scores than boys with autism spectrum disorder. However, compared to typically developing girls, girls with autism spectrum disorder showed subtle differences in reciprocal behaviour. The sex-specific response patterns in autism spectrum disorder can inform and improve the diagnostic assessment of autism in females.

Sex-Specific Patterns of Aberrant Brain Function in First-Episode Treatment-Naive Patients with Schizophrenia.

PubMed

Lei, Wei; Li, Mingli; Deng, Wei; Zhou, Yi; Ma, Xiaohong; Wang, Qiang; Guo, Wanjun; Li, Yinfei; Jiang, Lijun; Han, Yuanyuan; Huang, Chaohua; Hu, Xun; Li, Tao

2015-07-16

Male and female patients with schizophrenia show significant differences in a number of important clinical features, yet the neural substrates of these differences are still poorly understood. Here we explored the sex differences in the brain functional aberrations in 124 treatment-naïve patients with first-episode schizophrenia (61 males), compared with 102 age-matched healthy controls (50 males). Maps of degree centrality (DC) and amplitude of low-frequency fluctuations (ALFF) were constructed using resting-state functional magnetic resonance imaging data and compared between groups. We found that: (1) Selective DC reduction was observed in the right putamen (Put_R) in male patients and the left middle frontal gyrus (MFG) in female patients; (2) Functional connectivity analysis (using Put_R and MFG as seeds) found that male and female patients have disturbed functional integration in two separate networks, i.e., the sensorimotor network and the default mode network; (3) Significant ALFF alterations were also observed in these two networks in both genders; (4) Sex specific brain functional alterations were associated with various symptoms in patients. These results suggested that sex-specific patterns of functional aberration existed in schizophrenia, and these patterns were associated with the clinical features both in male and female patients.

Sex-specific effects of a parasite evolving in a female-biased host population

PubMed Central

2012-01-01

Background Males and females differ in many ways and might present different opportunities and challenges to their parasites. In the same way that parasites adapt to the most common host type, they may adapt to the characteristics of the host sex they encounter most often. To explore this hypothesis, we characterized host sex-specific effects of the parasite Pasteuria ramosa, a bacterium evolving in naturally, strongly, female-biased populations of its host Daphnia magna. Results We show that the parasite proliferates more successfully in female hosts than in male hosts, even though males and females are genetically identical. In addition, when exposure occurred when hosts expressed a sexual dimorphism, females were more infected. In both host sexes, the parasite causes a similar reduction in longevity and leads to some level of castration. However, only in females does parasite-induced castration result in the gigantism that increases the carrying capacity for the proliferating parasite. Conclusions We show that mature male and female Daphnia represent different environments and reveal one parasite-induced symptom (host castration), which leads to increased carrying capacity for parasite proliferation in female but not male hosts. We propose that parasite induced host castration is a property of parasites that evolved as an adaptation to specifically exploit female hosts. PMID:23249484

Sex-specific effects of a parasite evolving in a female-biased host population.

PubMed

Duneau, David; Luijckx, Pepijn; Ruder, Ludwig F; Ebert, Dieter

2012-12-18

Males and females differ in many ways and might present different opportunities and challenges to their parasites. In the same way that parasites adapt to the most common host type, they may adapt to the characteristics of the host sex they encounter most often. To explore this hypothesis, we characterized host sex-specific effects of the parasite Pasteuria ramosa, a bacterium evolving in naturally, strongly, female-biased populations of its host Daphnia magna. We show that the parasite proliferates more successfully in female hosts than in male hosts, even though males and females are genetically identical. In addition, when exposure occurred when hosts expressed a sexual dimorphism, females were more infected. In both host sexes, the parasite causes a similar reduction in longevity and leads to some level of castration. However, only in females does parasite-induced castration result in the gigantism that increases the carrying capacity for the proliferating parasite. We show that mature male and female Daphnia represent different environments and reveal one parasite-induced symptom (host castration), which leads to increased carrying capacity for parasite proliferation in female but not male hosts. We propose that parasite induced host castration is a property of parasites that evolved as an adaptation to specifically exploit female hosts.

Impulsiveness, and trait displaced aggression among drug using female sex traders

PubMed Central

Clingan, Sarah E.; Fisher, Dennis G.; Pedersen, William C.; Reynolds, Grace L.; Xandre, Pamela

2016-01-01

Objective This study compared women who sex trade for drugs, money, or both compared to neither (did not sex trade), and introduced the concept of trait displaced aggression to the literature on sex trading. Methods Female participants (n = 1055) were recruited from a low-income area of southern California. Measures included: the Risk Behavior Assessment (RBA), Barratt Impulsivity Scale (BIS), Eysenck Impulsiveness Scale (EIS), and the Displaced Aggression Questionnaire (DAQ). Results Women who traded sex for both drugs and money used crack cocaine, powder cocaine, and alcohol significantly more, scored higher on the BIS, and the EIS, and were significantly older. Those who only sex traded for drugs used more amphetamine, heroin, and injected drugs more days. They were also higher on the DAQ and all of the DAQ subscales. Those who traded for money only used marijuana more and were more likely to use marijuana before sex. Conclusions This study may help address specific issues unique to those who sex trade for different commodities in that the drugs used are different and the underlying personality characteristics are different. PMID:27082265

Sex differences in stress regulation of arousal and cognition.

PubMed

Bangasser, Debra A; Eck, Samantha R; Telenson, Alexander M; Salvatore, Madeleine

2018-04-01

There are sex differences in the prevalence and presentation of many psychiatric disorders. For example, posttraumatic stress disorder (PTSD) and major depression are more common in women than men, and women with these disorders present with more hyperarousal symptoms than men. In contrast, attention deficit hyperactivity disorder (ADHD) and schizophrenia are more common in men than women, and men with these disorders have increased cognitive deficits compared to women. A shared feature of the aforementioned psychiatric disorders is the contribution of stressful events to their onset and/or severity. Here we propose that sex differences in stress responses bias females towards hyperarousal and males towards cognitive deficits. Evidence from clinical and preclinical studies is detailed. We also describe underlying neurobiological mechanisms. For example, sex differences in stress receptor signaling and trafficking in the locus coeruleus-arousal center are detailed. In learning circuits, evidence for sex differences in dendritic morphology is provided. Finally, we describe how evaluating sex-specific mechanisms for responding to stress in female and male rodents can lead to better treatments for stress-related psychiatric disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

The Relevance of Sex Differences in Performance Fatigability

PubMed Central

Hunter, Sandra K.

2016-01-01

Performance fatigability differs between men and women for a range of fatiguing tasks. Women are usually less fatigable than men and this is most widely described for isometric fatiguing contractions, and some dynamic tasks. The sex difference in fatigability is specific to the task demands so that one mechanism is not universal, including any sex differences in skeletal muscle physiology, muscle perfusion and voluntary activation. However, there are substantial knowledge gaps about the task dependency of the sex differences in fatigability, the involved mechanisms and the relevance to clinical populations and with advanced age. The knowledge gaps are in part due to the significant deficits in the number of women included in performance fatigability studies despite a gradual increase in the inclusion of women over the last 20 years. Therefore, this review 1) provides a rationale for the limited knowledge about sex differences in performance fatigability, 2) summarizes the current knowledge on sex differences in fatigability and the potential mechanisms across a range of tasks, 3) highlights emerging areas of opportunity in clinical populations, and 4) suggests strategies to close the knowledge gap and understanding the relevance of sex differences in performance fatigability. The limited understanding about sex differences in fatigability in healthy and clinical populations, presents as a field ripe with opportunity for high impact studies. Such studies will inform on the limitations of men and women during athletic endeavors, ergonomic tasks and daily activities. Because fatigability is required for effective neuromuscular adaptation, sex differences in fatigability studies will also inform on optimal strategies for training and rehabilitation in both men and women. PMID:27015385

Sex differences in complex regional pain syndrome type I (CRPS-I) in mice.

PubMed

Tang, Chaoliang; Li, Juan; Tai, Wai Lydia; Yao, Weifeng; Zhao, Bo; Hong, Junmou; Shi, Si; Wang, Song; Xia, Zhongyuan

2017-01-01

Sex differences have been increasingly highlighted in complex regional pain syndrome (CRPS) in clinical practice. In CRPS type I (CRPS-I), although inflammation and oxidative stress have been implicated in its pathogenesis, whether pain behavior and the underlying mechanism are sex-specific is unclear. In the present study, we sought to explore whether sex differences have an impact on inflammation, oxidative stress, and pain sensitivity in CRPS-I. Chronic post-ischemia pain (CPIP) was established in both male and female mice as an animal model of CRPS-I. Edema and mechanical allodynia of bilateral hind paws were assessed after reperfusion. Blood samples were analyzed for serum levels of oxidative stress markers and inflammatory cytokines. Both male and female mice developed edema. Male mice developed CPIP at day 3 after reperfusion; female mice developed CPIP at day 2 after reperfusion. Female mice displayed significantly earlier and higher mechanical allodynia in the ischemic hind paw, which was associated with higher serum levels of IL-2, TNF-α, isoprostanes, 8 OhdG, and malondialdehyde at day 2 after reperfusion. Moreover, female mice showed significantly lower SOD and IL-4 compared to male mice at day 2 after reperfusion. Our results indicate that sex differences in inflammatory and oxidative stress states may play a central role in the sex-specific nociceptive hypersensitivity in CRPS-I, and offer a new insight into pharmacology treatments to improve pain management with CRPS.

Effect of sex on ethanol consumption and conditioned taste aversion in adolescent and adult rats.

PubMed

Schramm-Sapyta, Nicole L; Francis, Reynold; MacDonald, Andrea; Keistler, Colby; O'Neill, Lauren; Kuhn, Cynthia M

2014-04-01

Vulnerability to alcoholism is determined by many factors, including the balance of pleasurable vs. aversive alcohol-induced sensations: pleasurable sensations increase intake, while aversive sensations decrease it. Female sex and adolescent age are associated with lower sensitivity to intake-reducing effects and more rapid development of alcohol abuse. This study assessed voluntary drinking and the aversive effects of alcohol to determine whether these measures are inversely related across the sexes and development. Voluntary drinking of 20 % ethanol in an every-other-day (EOD) availability pattern and the dose-response relationship of ethanol conditioned taste aversion (CTA) were assessed in male and female adolescent and adult rats. CTA was sex specific in adult but not adolescent rats, with adult females exhibiting less aversion. Voluntary ethanol consumption varied according to age and individual differences but was not sex specific. Adolescents initially drank more than adults, exhibited greater day-to-day variation in consumption, were more susceptible to the alcohol deprivation effect, and took longer to establish individual differences in consumption patterns. These results show that the emergence of intake patterns differs between adolescents and adults. Adolescents as a group initiate drinking at high levels but decrease intake as they mature. A subset of adolescents maintained high drinking levels into adulthood. In contrast, most adults consumed at steady, low levels, but a small subset quickly established and maintained high-consumption patterns. Adolescents also showed marked deprivation-induced increases. Sex differences were not observed in EOD drinking during either adolescence or adulthood.

Transactional Sex Risk across a Typology of Rural and Urban Female Sex Workers in Indonesia: A Mixed Methods Study

PubMed Central

Puradiredja, Dewi Ismajani; Coast, Ernestina

2012-01-01

Context-specific typologies of female sex workers (FSWs) are essential for the design of HIV intervention programming. This study develops a novel FSW typology for the analysis of transactional sex risk in rural and urban settings in Indonesia. Mixed methods include a survey of rural and urban FSWs (n = 310), in-depth interviews (n = 11), key informant interviews (n = 5) and ethnographic assessments. Thematic analysis categorises FSWs into 5 distinct groups based on geographical location of their sex work settings, place of solicitation, and whether sex work is their primary occupation. Multiple regression analysis shows that the likelihood of consistent condom use was higher among urban venue-based FSWs for whom sex work is not the only source of income than for any of the other rural and urban FSW groups. This effect was explained by the significantly lower likelihood of consistent condom use by rural venue-based FSWs (adjusted OR: 0.34 95% CI 0.13–0.90, p = 0.029). The FSW typology and differences in organisational features and social dynamics are more closely related to the risk of unprotected transactional sex, than levels of condom awareness and availability. Interventions need context-specific strategies to reach the different FSWs identified by this study's typology. PMID:23285205

Conflict on the Sex Chromosomes: Cause, Effect, and Complexity

PubMed Central

Mank, Judith E.; Hosken, David J.; Wedell, Nina

2014-01-01

Intralocus sexual conflict and intragenomic conflict both affect sex chromosome evolution and can in extreme cases even cause the complete turnover of sex chromosomes. Additionally, established sex chromosomes often become the focus of heightened conflict. This creates a tangled relationship between sex chromosomes and conflict with respect to cause and effect. To further complicate matters, sexual and intragenomic conflict may exacerbate one another and thereby further fuel sex chromosome change. Different magnitudes and foci of conflict offer potential explanations for lineage-specific variation in sex chromosome evolution and answer long-standing questions as to why some sex chromosomes are remarkably stable, whereas others show rapid rates of evolutionary change. PMID:25280765

A small-area ecologic study of myocardial infarction, neighborhood deprivation, and sex: a Bayesian modeling approach.

PubMed

Deguen, Séverine; Lalloue, Benoît; Bard, Denis; Havard, Sabrina; Arveiler, Dominique; Zmirou-Navier, Denis

2010-07-01

Socioeconomic inequalities in the risk of coronary heart disease (CHD) are well documented for men and women. CHD incidence is greater for men but its association with socioeconomic status is usually found to be stronger among women. We explored the sex-specific association between neighborhood deprivation level and the risk of myocardial infarction (MI) at a small-area scale. We studied 1193 myocardial infarction events in people aged 35-74 years in the Strasbourg metropolitan area, France (2000-2003). We used a deprivation index to assess the neighborhood deprivation level. To take into account spatial dependence and the variability of MI rates due to the small number of events, we used a hierarchical Bayesian modeling approach. We fitted hierarchical Bayesian models to estimate sex-specific relative and absolute MI risks across deprivation categories. We tested departure from additive joint effects of deprivation and sex. The risk of MI increased with the deprivation level for both sexes, but was higher for men for all deprivation classes. Relative rates increased along the deprivation scale more steadily for women and followed a different pattern: linear for men and nonlinear for women. Our data provide evidence of effect modification, with departure from an additive joint effect of deprivation and sex. We document sex differences in the socioeconomic gradient of MI risk in Strasbourg. Women appear more susceptible at levels of extreme deprivation; this result is not a chance finding, given the large difference in event rates between men and women.

Neurocognitive performance in drug-dependent males and females with posttraumatic stress disorder symptoms.

PubMed

Paxton, Jessica L; Vassileva, Jasmin; Gonzalez, Raul; Maki, Pauline M; Martin, Eileen M

2012-01-01

Sex differences in neurobiological mechanisms of substance dependence are well documented but studies of sex differences in associated neurocognitive deficits have produced inconsistent results. Posttraumatic stress disorder (PTSD) is comorbid with substance dependence and frequently affects neurocognition. Thus, we investigated the effects of sex and PTSD symptoms on sustained attention and inhibition abilities among 126 female and 297 male substance-dependent individuals (SDIs) using the Immediate Memory Test (IMT). Females with significant PTSD (PTSD+) symptoms demonstrated significantly impaired IMT performance relative to other participants. These results represent progress in efforts to delineate sex-specific risk factors for neurocognitive deficits among SDIs.

Gender-stereotyping and cognitive sex differences in mixed- and same-sex groups.

PubMed

Hirnstein, Marco; Coloma Andrews, Lisa; Hausmann, Markus

2014-11-01

Sex differences in specific cognitive abilities are well documented, but the biological, psychological, and sociocultural interactions that may underlie these differences are largely unknown. We examined within a biopsychosocial approach how gender stereotypes affect cognitive sex differences when adult participants were tested in mixed- or same-sex groups. A total of 136 participants (70 women) were allocated to either mixed- or same-sex groups and completed a battery of sex-sensitive cognitive tests (i.e., mental rotation, verbal fluency, perceptual speed) after gender stereotypes or gender-neutral stereotypes (control) were activated. To study the potential role of testosterone as a mediator for group sex composition and stereotype boost/threat effects, saliva samples were taken before the stereotype manipulation and after cognitive testing. The results showed the typical male and female advantages in mental rotation and verbal fluency, respectively. In general, men and women who were tested in mixed-sex groups and whose gender stereotypes had not been activated performed best. Moreover, a stereotype threat effect emerged in verbal fluency with reduced performance in gender stereotyped men but not women. Testosterone levels did not mediate the effects of group sex composition and stereotype threat nor did we find any relationship between testosterone and cognitive performance in men and women. Taken together, the findings suggest that an interaction of gender stereotyping and group sex composition affects the performance of men and women in sex-sensitive cognitive tasks. Mixed-sex settings can, in fact, increase cognitive performance as long as gender-stereotyping is prevented.

Effects of sex and COMT genotype on environmentally modulated cognitive control in mice

PubMed Central

Papaleo, Francesco; Erickson, Lucy; Liu, Guangping; Chen, Jingshan; Weinberger, Daniel R.

2012-01-01

Cognitive functioning differs between males and females, likely in part related to genetic dimorphisms. An example of a common genetic variation reported to have sexually dimorphic effects on cognition and temperament in humans is the Val/Met polymorphism in catechol-O-methyltransferase (COMT). We tested male and female wild-type mice (+/+) and their COMT knockout littermates (+/− and −/−) in the five-choice serial reaction time task (5CSRTT) to investigate the effects of sex, COMT genotype, and their interactions with environmental manipulations of cognitive functions such as attention, impulsivity, compulsivity, motivation, and rule-reversal learning. No sex- or COMT-dependent differences were present in the basic acquisition of the five-choice serial reaction time task. In contrast, specific environmental manipulations revealed a variety of sex- and COMT-dependent effects. Following an experimental change to trigger impulsive responding, the sexes showed similar increases in impulsiveness, but males eventually habituated whereas females did not. Moreover, COMT knockout mice were more impulsive compared with wild-type littermates. Manipulations involving mild stress adversely affected cognitive performance in males, and particularly COMT knockout males, but not in females. In contrast, following amphetamine treatment, subtle sex by genotype and sex by treatment interactions emerged primarily limited to compulsive behavior. After repeated testing, female mice showed improved performance, working harder and eventually outperforming males. Finally, removing the food-restriction condition enhanced sex and COMT differences, revealing that overall, females outperform males and COMT knockout males outperform their wild-type littermates. These findings illuminate complex sex- and COMT-related effects and their interactions with environmental factors to influence specific executive cognitive domains. PMID:23169629

Sex differences in a human analogue of the Radial Arm Maze: the "17-Box Maze Test".

PubMed

Rahman, Qazi; Abrahams, Sharon; Jussab, Fardin

2005-08-01

This study investigated sex differences in spatial memory using a human analogue of the Radial Arm Maze: a revision on the Nine Box Maze originally developed by called the 17-Box Maze Test herein. The task encourages allocentric spatial processing, dissociates object from spatial memory, and incorporates a within-participants design to provide measures of location and object, working and reference memory. Healthy adult males and females (26 per group) were administered the 17-Box Maze Test, as well as mental rotation and a verbal IQ test. Females made significantly fewer errors on this task than males. However, post hoc analysis revealed that the significant sex difference was specific to object, rather than location, memory measures. These were medium to large effect sizes. The findings raise the issue of task- and component-specific sexual dimorphism in cognitive mapping.

Countries with Higher Levels of Gender Equality Show Larger National Sex Differences in Mathematics Anxiety and Relatively Lower Parental Mathematics Valuation for Girls

PubMed Central

2016-01-01

Despite international advancements in gender equality across a variety of societal domains, the underrepresentation of girls and women in Science, Technology, Engineering, and Mathematics (STEM) related fields persists. In this study, we explored the possibility that the sex difference in mathematics anxiety contributes to this disparity. More specifically, we tested a number of predictions from the prominent gender stratification model, which is the leading psychological theory of cross-national patterns of sex differences in mathematics anxiety and performance. To this end, we analyzed data from 761,655 15-year old students across 68 nations who participated in the Programme for International Student Assessment (PISA). Most importantly and contra predictions, we showed that economically developed and more gender equal countries have a lower overall level of mathematics anxiety, and yet a larger national sex difference in mathematics anxiety relative to less developed countries. Further, although relatively more mothers work in STEM fields in more developed countries, these parents valued, on average, mathematical competence more in their sons than their daughters. The proportion of mothers working in STEM was unrelated to sex differences in mathematics anxiety or performance. We propose that the gender stratification model fails to account for these national patterns and that an alternative model is needed. In the discussion, we suggest how an interaction between socio-cultural values and sex-specific psychological traits can better explain these patterns. We also discuss implications for policies aiming to increase girls’ STEM participation. PMID:27100631

Sex-specific effects of maternal anthropometrics on body composition at birth

PubMed Central

O’tierney-ginn, Perrie; Presley, Ms. Larraine; Minium, Ms. Judi; Hauguel deMouzon, Sylvie; Catalano, Patrick

2014-01-01

Objective To assess if maternal factors associated with fetal lean and fat mass differ between sexes. Study Design Secondary analysis of a prospective cohort delivering via scheduled Cesarean from 2004–2013. Maternal blood was collected prior to surgery for metabolic parameters. Placental weight and neonatal anthropometrics were measured within 48 hrs. Anthropometric differences between sexes were assessed with Student’s t-test. Multiple stepwise regression analysis assessed the relationship between independent maternal variables and neonatal lean body mass (LBM), fat mass (FM) or percent (%) fat as dependent variables in males and females combined and separately. Results We analyzed 360 women with normal glucose tolerance and wide range of pregravid body mass index (BMI, 16–64 kg/m2) and their offspring (N=194 males and 166 females). Males had more FM (mean difference 40 ± 18 g, P=0.03) and LBM (mean difference 158 ± 34 g, P<0.0001) than females. Percent body fat and measured maternal variables did not differ between sexes. In both sexes, placental weight had the strongest correlation with both neonatal LBM and FM, accounting for 20–39% of the variance. In males, maternal height, BMI and weight gain were significant predictors of both lean and fat mass. In females, plasma interleukin-6 and C-reactive protein were respectively independently associated with percent body fat and lean body mass. Conclusion Our findings suggest that the body composition and inflammatory environment of the mother modulate the metabolic fitness of neonates, as predicted by fat and lean mass, in a sex-specific manner. PMID:24858203

Countries with Higher Levels of Gender Equality Show Larger National Sex Differences in Mathematics Anxiety and Relatively Lower Parental Mathematics Valuation for Girls.

PubMed

Stoet, Gijsbert; Bailey, Drew H; Moore, Alex M; Geary, David C

2016-01-01

Despite international advancements in gender equality across a variety of societal domains, the underrepresentation of girls and women in Science, Technology, Engineering, and Mathematics (STEM) related fields persists. In this study, we explored the possibility that the sex difference in mathematics anxiety contributes to this disparity. More specifically, we tested a number of predictions from the prominent gender stratification model, which is the leading psychological theory of cross-national patterns of sex differences in mathematics anxiety and performance. To this end, we analyzed data from 761,655 15-year old students across 68 nations who participated in the Programme for International Student Assessment (PISA). Most importantly and contra predictions, we showed that economically developed and more gender equal countries have a lower overall level of mathematics anxiety, and yet a larger national sex difference in mathematics anxiety relative to less developed countries. Further, although relatively more mothers work in STEM fields in more developed countries, these parents valued, on average, mathematical competence more in their sons than their daughters. The proportion of mothers working in STEM was unrelated to sex differences in mathematics anxiety or performance. We propose that the gender stratification model fails to account for these national patterns and that an alternative model is needed. In the discussion, we suggest how an interaction between socio-cultural values and sex-specific psychological traits can better explain these patterns. We also discuss implications for policies aiming to increase girls' STEM participation.

High-throughput avian molecular sexing by SYBR green-based real-time PCR combined with melting curve analysis.

PubMed

Chang, Hsueh-Wei; Cheng, Chun-An; Gu, De-Leung; Chang, Chia-Che; Su, San-Hua; Wen, Cheng-Hao; Chou, Yii-Cheng; Chou, Ta-Ching; Yao, Cheng-Te; Tsai, Chi-Li; Cheng, Chien-Chung

2008-02-12

Combination of CHD (chromo-helicase-DNA binding protein)-specific polymerase chain reaction (PCR) with electrophoresis (PCR/electrophoresis) is the most common avian molecular sexing technique but it is lab-intensive and gel-required. Gender determination often fails when the difference in length between the PCR products of CHD-Z and CHD-W genes is too short to be resolved. Here, we are the first to introduce a PCR-melting curve analysis (PCR/MCA) to identify the gender of birds by genomic DNA, which is gel-free, quick, and inexpensive. Spilornis cheela hoya (S. c. hoya) and Pycnonotus sinensis (P. sinensis) were used to illustrate this novel molecular sexing technique. The difference in the length of CHD genes in S. c. hoya and P. sinensis is 13-, and 52-bp, respectively. Using Griffiths' P2/P8 primers, molecular sexing failed both in PCR/electrophoresis of S. c. hoya and in PCR/MCA of S. c. hoya and P. sinensis. In contrast, we redesigned sex-specific primers to yield 185- and 112-bp PCR products for the CHD-Z and CHD-W genes of S. c. hoya, respectively, using PCR/MCA. Using this specific primer set, at least 13 samples of S. c. hoya were examined simultaneously and the Tm peaks of CHD-Z and CHD-W PCR products were distinguished. In this study, we introduced a high-throughput avian molecular sexing technique and successfully applied it to two species. This new method holds a great potential for use in high throughput sexing of other avian species, as well.

Mad men, women and steroid cocktails: a review of the impact of sex and other factors on anabolic androgenic steroids effects on affective behaviors.

PubMed

Onakomaiya, Marie M; Henderson, Leslie P

2016-02-01

For several decades, elite athletes and a growing number of recreational consumers have used anabolic androgenic steroids (AAS) as performance enhancing drugs. Despite mounting evidence that illicit use of these synthetic steroids has detrimental effects on affective states, information available on sex-specific actions of these drugs is lacking. The focus of this review is to assess information to date on the importance of sex and its interaction with other environmental factors on affective behaviors, with an emphasis on data derived from non-human studies. The PubMed database was searched for relevant studies in both sexes. Studies examining AAS use in females are limited, reflecting the lower prevalence of use in this sex. Data, however, indicate significant sex-specific differences in AAS effects on anxiety-like and aggressive behaviors, interactions with other drugs of abuse, and the interplay of AAS with other environmental factors such as diet and exercise. Current methods for assessing AAS use have limitations that suggest biases of both under- and over-reporting, which may be amplified for females who are poorly represented in self-report studies of human subjects and are rarely used in animal studies. Data from animal literature suggest that there are significant sex-specific differences in the impact of AAS on aggression, anxiety, and concomitant use of other abused substances. These results have relevance for human females who take these drugs as performance-enhancing substances and for transgender XX individuals who may illicitly self-administer AAS as they transition to a male gender identity.

Polymorphic mimicry, microhabitat use, and sex-specific behaviour.

PubMed

Joron, M

2005-05-01

In order to assess the adaptive importance of microhabitat segregation for the maintenance of mimetic diversity, I explore how flight height varies between the sympatric forms of the polymorphic butterfly Heliconius numata and their respective models in the genus Melinaea. There is no evidence for vertical stratification of mimicry rings in these tiger-patterned butterflies, but males of H. numata tend to fly significantly higher than females and the Melinaea models. This difference in microhabitat preference likely results from females searching for host plants whereas males are patrolling for mates. I then present an extension of Muller's mimicry model for the case of partial behavioural or spatial segregation of sexes. The analysis suggests that sex-specific behaviours can make mimicry more beneficial, simply by reducing the effective population size participating in mimicry. The interaction between mimicry and sex-specific behaviours may therefore facilitate the evolution of polymorphism via enhanced, fine-scale local adaptation.

Effect of Sex and Prior Exposure to a Cafeteria Diet on the Distribution of Sex Hormones between Plasma and Blood Cells

PubMed Central

Romero, María del Mar; Fernández-López, José Antonio; Remesar, Xavier; Alemany, Marià

2012-01-01

It is generally assumed that steroid hormones are carried in the blood free and/or bound to plasma proteins. We investigated whether blood cells were also able to bind/carry sex-related hormones: estrone, estradiol, DHEA and testosterone. Wistar male and female rats were fed a cafeteria diet for 30 days, which induced overweight. The rats were fed the standard rat diet for 15 additional days to minimize the immediate effects of excess ingested energy. Controls were always kept on standard diet. After the rats were killed, their blood was used for 1) measuring plasma hormone levels, 2) determining the binding of labeled hormones to washed red blood cells (RBC), 3) incubating whole blood with labeled hormones and determining the distribution of label between plasma and packed cells, discounting the trapped plasma volume, 4) determining free plasma hormone using labeled hormones, both through membrane ultrafiltration and dextran-charcoal removal. The results were computed individually for each rat. Cells retained up to 32% estrone, and down to 10% of testosterone, with marked differences due to sex and diet (the latter only for estrogens, not for DHEA and testosterone). Sex and diet also affected the concentrations of all hormones, with no significant diet effects for estradiol and DHEA, but with considerable interaction between both factors. Binding to RBC was non-specific for all hormones. Estrogen distribution in plasma compartments was affected by sex and diet. In conclusion: a) there is a large non-specific RBC-carried compartment for estrone, estradiol, DHEA and testosterone deeply affected by sex; b) Prior exposure to a cafeteria (hyperlipidic) diet induced hormone distribution changes, affected by sex, which hint at sex-related structural differences in RBC membranes; c) We postulate that the RBC compartment may contribute to maintain free (i.e., fully active) sex hormone levels in a way similar to plasma proteins non-specific binding. PMID:22479617

Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses.

PubMed

Argue, Kathryn J; Neckameyer, Wendi S

2014-07-01

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. Copyright © 2014 the American Physiological Society.

Senescence rates and late adulthood reproductive success are strongly influenced by personality in a long-lived seabird

PubMed Central

Patrick, Samantha C.; Weimerskirch, Henri

2015-01-01

Studies are increasingly demonstrating that individuals differ in their rate of ageing, and this is postulated to emerge from a trade-off between current and future reproduction. Recent theory predicts a correlation between individual personality and life-history strategy, and from this comes the prediction that personality may predict the intensity of senescence. Here we show that boldness correlates with reproductive success and foraging behaviour in wandering albatrosses, with strong sex-specific differences. Shy males show a strong decline in reproductive performance with age, and bold females have lower reproductive success in later adulthood. In both sexes, bolder birds have longer foraging trips and gain more mass per trip as they get older. However, the benefit of this behaviour appears to differ between the sexes, such that it is only matched by high reproductive success in males. Together our results suggest that personality linked foraging adaptations with age are strongly sex-specific in their fitness benefits and that the impact of boldness on senescence is linked to ecological parameters. PMID:25473008

Demand for Colonoscopy in Colorectal Cancer Screening Using a Quantitative Fecal Immunochemical Test and Age/Sex-Specific Thresholds for Test Positivity.

PubMed

Chen, Sam Li-Sheng; Hsu, Chen-Yang; Yen, Amy Ming-Fang; Young, Graeme P; Chiu, Sherry Yueh-Hsia; Fann, Jean Ching-Yuan; Lee, Yi-Chia; Chiu, Han-Mo; Chiou, Shu-Ti; Chen, Hsiu-Hsi

2018-06-01

Background: Despite age and sex differences in fecal hemoglobin (f-Hb) concentrations, most fecal immunochemical test (FIT) screening programs use population-average cut-points for test positivity. The impact of age/sex-specific threshold on FIT accuracy and colonoscopy demand for colorectal cancer screening are unknown. Methods: Using data from 723,113 participants enrolled in a Taiwanese population-based colorectal cancer screening with single FIT between 2004 and 2009, sensitivity and specificity were estimated for various f-Hb thresholds for test positivity. This included estimates based on a "universal" threshold, receiver-operating-characteristic curve-derived threshold, targeted sensitivity, targeted false-positive rate, and a colonoscopy-capacity-adjusted method integrating colonoscopy workload with and without age/sex adjustments. Results: Optimal age/sex-specific thresholds were found to be equal to or lower than the universal 20 μg Hb/g threshold. For older males, a higher threshold (24 μg Hb/g) was identified using a 5% false-positive rate. Importantly, a nonlinear relationship was observed between sensitivity and colonoscopy workload with workload rising disproportionately to sensitivity at 16 μg Hb/g. At this "colonoscopy-capacity-adjusted" threshold, the test positivity (colonoscopy workload) was 4.67% and sensitivity was 79.5%, compared with a lower 4.0% workload and a lower 78.7% sensitivity using 20 μg Hb/g. When constrained on capacity, age/sex-adjusted estimates were generally lower. However, optimizing age/-sex-adjusted thresholds increased colonoscopy demand across models by 17% or greater compared with a universal threshold. Conclusions: Age/sex-specific thresholds improve FIT accuracy with modest increases in colonoscopy demand. Impact: Colonoscopy-capacity-adjusted and age/sex-specific f-Hb thresholds may be useful in optimizing individual screening programs based on detection accuracy, population characteristics, and clinical capacity. Cancer Epidemiol Biomarkers Prev; 27(6); 704-9. ©2018 AACR . ©2018 American Association for Cancer Research.

Sex and Gender Roles in Relation to Mental Health and Allostatic Load.

PubMed

Juster, Robert-Paul; Pruessner, Jens C; Desrochers, Alexandra Bisson; Bourdon, Olivier; Durand, Nadia; Wan, Nathalie; Tourjman, Valérie; Kouassi, Edouard; Lesage, Alain; Lupien, Sonia J

2016-09-01

Beyond male/female binaries, gender roles represent masculine and feminine traits that we assimilate and enact throughout life span development. Bem proposed that "androgynous" individuals adeptly adapt to different contexts by alternating from a strong repertoire of both masculine and feminine gender roles. By contrast, "undifferentiated" individuals may not adapt as well to social norms because of weak self-endorsed masculinity and femininity. Among 204 adults (mean [standard error] age = 40.4 [0.9] years; 70% women) working in a psychiatric hospital, we hypothesized that androgynous individuals would present better mental health and less physiological dysregulations known as allostatic load (AL) than undifferentiated individuals. AL was indexed using 20 biomarkers using the conventional "all-inclusive" formulation that ascribes cutoffs without regard for sex or an alternative "sex-specific" formulation with cutoffs tailored for each sex separately while controlling for sex hormones (testosterone, estradiol, progesterone). Well-validated questionnaires were used. Independent of sex, androgynous individuals experienced higher self-esteem and well-being and lower depressive symptoms than did undifferentiated individuals. Men manifested higher AL than did women using the all-inclusive AL index (p = .044, ηP = 0.025). By contrast, the sex-specific AL algorithm unmasked a sex by gender roles interaction for AL (p = .043, ηP = 0.048): with the highest AL levels in undifferentiated men. Analysis using a gender index based on seven gendered constructs revealed that a greater propensity toward feminine characteristics correlated only with elevated sex-specific AL (r = 0.163, p = .025). Beyond providing psychobiological evidence for Bem's theory, this study highlights how sex-specific AL formulations detect the effects of sociocultural gender.

Genetic and environmental influences on skeletal muscle phenotypes as a function of age and sex in large, multigenerational families of African heritage.

PubMed

Prior, Steven J; Roth, Stephen M; Wang, Xiaojing; Kammerer, Candace; Miljkovic-Gacic, Iva; Bunker, Clareann H; Wheeler, Victor W; Patrick, Alan L; Zmuda, Joseph M

2007-10-01

The aim of this study was to estimate the heritability of and environmental contributions to skeletal muscle phenotypes (appendicular lean mass and calf muscle cross-sectional area) in subjects of African descent and to determine whether heritability estimates are impacted by sex or age. Body composition was measured by dual-energy X-ray absorptiometry and computed tomography in 444 men and women aged 18 yr and older (mean: 43 yr) from eight large, multigenerational Afro-Caribbean families (family size range: 21-112). Using quantitative genetic methods, we estimated heritability and the association of anthropometric, lifestyle, and medical variables with skeletal muscle phenotypes. In the overall group, we estimated the heritability of lean mass and calf muscle cross-sectional area (h(2) = 0.18-0.23, P < 0.01) and contribution of environmental factors to these phenotypes (r(2) = 0.27-0.55, P < 0.05). In our age-specific analysis, the heritability of leg lean mass was lower in older vs. younger individuals (h(2) = 0.05 vs. 0.23, respectively, P = 0.1). Sex was a significant covariate in our models (P < 0.001), although sex-specific differences in heritability varied depending on the lean mass phenotype analyzed. High genetic correlations (rho(G) = 0.69-0.81; P < 0.01) between different lean mass measures suggest these traits share a large proportion of genetic components. Our results demonstrate the heritability of skeletal muscle traits in individuals of African heritage and that heritability may differ as a function of sex and age. As the loss of skeletal muscle mass is related to metabolic abnormalities, disability, and mortality in older individuals, further research is warranted to identify specific genetic loci that contribute to these traits in general and in a sex- and age-specific manner.

Little evidence for intralocus sexual conflict over the optimal intake of nutrients for life span and reproduction in the black field cricket Teleogryllus commodus.

PubMed

Rapkin, James; Archer, C Ruth; Grant, Charles E; Jensen, Kim; House, Clarissa M; Wilson, Alastair J; Hunt, John

2017-09-01

There is often large divergence in the effects of key nutrients on life span (LS) and reproduction in the sexes, yet nutrient intake is regulated in the same way in males and females given dietary choice. This suggests that the sexes are constrained from feeding to their sex-specific nutritional optima for these traits. Here, we examine the potential for intralocus sexual conflict (IASC) over optimal protein and carbohydrate intake for LS and reproduction to constrain the evolution of sex-specific nutrient regulation in the field cricket, Teleogryllus commodus. We show clear sex differences in the effects of protein and carbohydrate intake on LS and reproduction and strong positive genetic correlations between the sexes for the regulated intake of these nutrients. However, the between-sex additive genetic covariance matrix had very little effect on the predicted evolutionary response of nutrient regulation in the sexes. Thus, IASC appears unlikely to act as an evolutionary constraint on sex-specific nutrient regulation in T. commodus. This finding is supported by clear sexual dimorphism in the regulated intake of these nutrients under dietary choice. However, nutrient regulation did not coincide with the nutritional optima for LS or reproduction in either sex, suggesting that IASC is not completely resolved in T. commodus. © 2017 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Sexual conflict resolved by invasion of a novel sex determiner in Lake Malawi cichlid fishes.

PubMed

Roberts, Reade B; Ser, Jennifer R; Kocher, Thomas D

2009-11-13

Sex determination mechanisms differ among animal species, but it is not clear how these differences evolve. New sex determiners may arise in response to sexual conflicts, which occur when traits benefit one sex but hinder the other. We identified the genetic basis for the orange-blotch (OB) color pattern, a trait under sexually antagonistic selection in the cichlid fish of Lake Malawi, East Africa. The OB phenotype is due to a cis-regulatory mutation in the Pax7 gene. OB provides benefits of camouflage to females but disrupts the species-specific male color patterns used for mate recognition. We suggest that the resulting sexual conflict over the OB allele has been resolved by selection for a novel female sex determination locus that has invaded populations with an ancestral male sex determination system.

Issues related to sex differences in antipsychotic treatment.

PubMed

Crawford, Mitchell B; DeLisi, Lynn E

2016-05-01

The effectiveness, side-effect profiles, and numerous other characteristics of antipsychotic medications have been extensively studied. However, the majority of publications do not address the many potential sex differences in efficacy and doses of medications, as well as other sex-specific considerations. Of studies that exist, some suggest that female patients respond to lower doses of antipsychotic medications than males and that side-effect profiles vary between the sexes. However, the majority of preclinical trials use only male laboratory animals, and human clinical trials consist of too few women to analyze their response as a separate group. Although changes in hormone production occurring at multiple stages throughout a women's life (such as during pregnancy, breast feeding, menopause, and postmenopausal) are presented as too complex to deal with in clinical trials, they could instead be embraced as clinical dilemmas that require additional study and consideration. We suggest that a focus should be made to reanalyze data from existing major treatment trials of antipsychotics to determine what medications specifically provide the most efficacy for female patients and at what dose range. In addition, new prospective studies are needed to specifically address appropriate adjustments in psychopharmacologic treatment for female patients during pregnancy, and when postmenopausal. More studies of the effects of antipsychotics on male and female fetuses in utero and during breast feeding are also needed to better manage women with schizophrenia and their offspring on a long-term basis in the community. There is currently too little known about sex differences in neuropharmacology. With the new USA National Institutes of Health policy to include sex in all new proposals, the time has come to close this gap in knowledge.

Sensitivity of the prefrontal GABAergic system to chronic stress in male and female mice: Relevance for sex differences in stress-related disorders.

PubMed

Shepard, Ryan; Page, Chloe E; Coutellier, Laurence

2016-09-22

Stress-induced modifications of the prefrontal cortex (PFC) are believed to contribute to the onset of mood disorders, such as depression and anxiety, which are more prevalent in women. In depression, the PFC is hypoactive; however the origin of this hypoactivity remains unclear. Possibly, stress could impact the prefrontal GABAergic inhibitory system that, as a result, impairs the functioning of downstream limbic structures controlling emotions. Preclinical evidence indicates that the female PFC is more sensitive to the effects of stress. These findings suggest that exposure to stress could lead to sex-specific alterations in prefrontal GABAergic signaling, which contribute to sex-specific abnormal functioning of limbic regions. These limbic changes could promote the onset of depressive and anxiety behaviors in a sex-specific manner, providing a possible mechanism mediating sex differences in the clinical presentation of stress-related mood disorders. We addressed this hypothesis using a mouse model of stress-induced depressive-like behaviors: the unpredictable chronic mild stress (UCMS) paradigm. We observed changes in prefrontal GABAergic signaling after exposure to UCMS most predominantly in females. Increased parvalbumin (PV) expression and decreased prefrontal neuronal activity were correlated in females with severe emotionality deficit following UCMS, and with altered activity of the amygdala. In males, small changes in emotionality following UCMS were associated with minor changes in prefrontal PV expression, and with hypoactivity of the nucleus accumbens. Our data suggest that prefrontal hypoactivity observed in stress-related mood disorders could result from stress-induced increases in PV expression, particularly in females. This increased vulnerability of the female prefrontal PV system to stress could underlie sex differences in the prevalence and symptomatology of stress-related mood disorders. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Sex-Specific Differences in the Association Between Childhood Adversity and Cardiovascular Disease in Adulthood: Evidence From a National Cohort Study.

PubMed

Garad, Yasmin; Maximova, Katerina; MacKinnon, Nathalie; McGrath, Jennifer J; Kozyrskyj, Anita L; Colman, Ian

2017-08-01

Childhood adversity increases the risk for cardiovascular disease (CVD) in adulthood. Previously proposed mechanisms suggest that the association is mediated by stress reactivity-known to be higher in women-and is aggravated by adult stress, but this has not yet been confirmed. Therefore, we investigated sex differences to better understand possible pathways from childhood adversity to CVD. The National Population Health Survey, a 15-year cohort study of Canadians aged 18-49 years at baseline was used. Logistic regression with interaction terms for sex and stressful life events was used to assess the risk of CVD after childhood adversity. In secondary analyses, we assessed mediation effects of depression, smoking, alcohol, exercise, and diet using the product of coefficient approach. Mediated moderation was subsequently used to explain sex-moderated effects. There was a strong association between childhood adversity and CVD (odds ratio [OR], 2.14; 95% confidence interval [CI], 1.56-2.94) for 3+ childhood adversities. The association was stronger with increasing stressful events, and female patients with 3+ stressful events exhibited the highest risk of CVD (OR, 4.40; 95% CI, 1.98-9.75). No association was found in men. Depression, smoking, and poor diet partially mediated the relationship between childhood adversity and CVD (14%, 9%, and 9%, respectively), but differences in these behaviours did not fully explain the sex-specific differences in the mediated moderation analysis. The effect of childhood adverse events on CVD is heightened among women, particularly women with stressful adulthoods, and this difference is not mediated by depression, smoking, or poor diet. These findings have important implications for understanding sex differences in CVD risk. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Sexual dimorphism in immune function changes during the annual cycle in house sparrows

NASA Astrophysics Data System (ADS)

Pap, Péter László; Czirják, Gábor Árpád; Vágási, Csongor István; Barta, Zoltán; Hasselquist, Dennis

2010-10-01

Difference between sexes in parasitism is a common phenomenon among birds, which may be related to differences between males and females in their investment into immune functions or as a consequence of differential exposure to parasites. Because life-history strategies change sex specifically during the annual cycle, immunological responses of the host aiming to reduce the impact of parasites may be sexually dimorphic. Despite the great complexity of the immune system, studies on immunoecology generally characterise the immune status through a few variables, often overlooking potentially important seasonal and gender effects. However, because of the differences in physiological and defence mechanisms among different arms of the immune system, we expect divergent responses of immune components to environmental seasonality. In male and female house sparrows ( Passer domesticus), we measured the major components of the immune system (innate, acquired, cellular and humoral) during four important life-history stages across the year: (1) mating, (2) breeding, (3) moulting and (4) during the winter capture and also following introduction to captivity in aviary. Different individuals were sampled from the same population during the four life cycle stages. We found that three out of eight immune variables showed a significant life cycle stage × sex interaction. The difference in immune response between the sexes was significant in five immune variables during the mating stage, when females had consistently stronger immune function than males, while variables varied generally non-significantly with sex during the remaining three life cycle stages. Our results show that the immune system is highly variable between life cycle stages and sexes, highlighting the potential fine tuning of the immune system to specific physiological states and environmental conditions.

Age and Sex Differences in Rates of Influenza-Associated Hospitalizations in Hong Kong.

PubMed

Wang, Xi-Ling; Yang, Lin; Chan, Kwok-Hung; Chan, King-Pan; Cao, Pei-Hua; Lau, Eric Ho-Yin; Peiris, J S Malik; Wong, Chit-Ming

2015-08-15

Few studies have explored age and sex differences in the disease burden of influenza, although men and women probably differ in their susceptibility to influenza infections. In this study, quasi-Poisson regression models were applied to weekly age- and sex-specific hospitalization numbers of pneumonia and influenza cases in the Hong Kong SAR, People's Republic of China, from 2004 to 2010. Age and sex differences were assessed by age- and sex-specific rates of excess hospitalization for influenza A subtypes A(H1N1), A(H3N2), and A(H1N1)pdm09 and influenza B, respectively. We found that, in children younger than 18 years, boys had a higher excess hospitalization rate than girls, with the male-to-female ratio of excess rate (MFR) ranging from 1.1 to 2.4. MFRs of hospitalization associated with different types/subtypes were less than 1.0 for adults younger than 40 years except for A(H3N2) (MFR = 1.6), while all the MFRs were equal to or higher than 1.0 in adults aged 40 years or more except for A(H1N1)pdm09 in elderly persons aged 65 years or more (MFR = 0.9). No MFR was found to be statistically significant (P < 0.05) for hospitalizations associated with influenza type/subtype. There is some limited evidence on age and sex differences in hospitalization associated with influenza in the subtropical city of Hong Kong. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Developmental and sex-specific differences in expression of neuropeptides derived from allatotropin gene in the silkmoth Bombyx mori.

PubMed

Bednár, Branislav; Roller, Ladislav; Čižmár, Daniel; Mitrová, Diana; Žitňan, Dušan

2017-05-01

Allatotropin (AT) and related neuropeptides are widespread bioactive molecules that regulate development, food intake and muscle contractions in insects and other invertebrates. In moths, alternative splicing of the at gene generates three mRNA precursors encoding AT with different combinations of three structurally similar AT-like peptides (ATLI-III). We used in situ hybridization and immunohistochemistry to map the differential expression of these transcripts during the postembryonic development of Bombyx mori. Transcript encoding AT alone was expressed in numerous neurons of the central nervous system and frontal ganglion, whereas transcripts encoding AT with ATLs were produced by smaller specific subgroups of neurons in larval stages. Metamorphosis was associated with considerable developmental changes and sex-specific differences in the expression of all transcripts. The most notable was the appearance of AT/ATL transcripts (1) in the brain lateral neurosecretory cells producing prothoracicotropic hormone; (2) in the male-specific cluster of about 20 neurons in the posterior region of the terminal abdominal ganglion; (3) in the female-specific medial neurons in the abdominal ganglia AG2-7. Immunohistochemical staining showed that these neurons produced a mixture of various neuropeptides and innervated diverse peripheral organs. Our data suggest that AT/ATL neuropeptides are involved in multiple stage- and sex-specific functions during the development of B. mori.

Sex differences in the association between gray matter volume and verbal creativity.

PubMed

Shi, Baoguo; Xu, Li; Chen, Qunlin; Qiu, Jiang

2017-08-02

The explanation for why significant sex differences are found in creativity has become an increasingly important topic. The current study applied a cognitive neuroscience perspective and voxel-based morphometry to investigate the sex differences for the association between verbal creativity and gray matter volume (GMV) in a large sample of healthy adults from the Chinese Mainland (163 men and 193 women). Furthermore, we sought to determine which brain regions are responsible for these differences. Our behavioral results showed a significant sex difference. Specifically, women scored higher than men on originality. The voxel-based morphometry results indicated that the relationship between originality and GMV differed between men and women in the left temporo-occipital junction. Higher originality scores in women were associated with more GMV. In contrast, higher originality scores in men were related to less GMV. These findings suggest the left temporo-occipital junction GMV plays a unique role in the sex differences in verbal creativity because women usually surpass men in semantic processing, which is the major function of the left temporal region.

Associations between biological markers of prenatal stress and infant negative emotionality are specific to sex.

PubMed

Braithwaite, Elizabeth C; Murphy, Susannah E; Ramchandani, Paul G; Hill, Jonathan

2017-12-01

Fetal programming is the idea that environmental stimuli can alter the development of the fetus, which may have a long-term effect on the child. We have recently reported that maternal prenatal cortisol predicts infant negative emotionality in a sex-dependent manner: high prenatal cortisol was associated with increased negative emotionality in females, and decreased negative emotionality in males. This study aims to test for this sex-specific effect in a different cohort, and investigate whether sex differences in fetal programming may be specific to glucocorticoid mechanisms by also examining a maternal salivary alpha-amylase (sAA) by sex interaction. 88 pregnant women (mean gestational age=27.4 weeks, SD=7.4) collected saliva samples at home over two working days to be assayed for the hormone cortisol (range=0.13-88.22nmol/l) and the enzyme alpha-amylase (range=4.57-554.8units/ml). Samples were collected at waking, 30-min post-waking and 12h post-waking. Two months after birth participants reported infant negative emotionality using the distress to limits subscale of the Infant Behavior Questionnaire. The interaction between maternal prenatal cortisol and infant sex to predict distress to limits approached significance (p=0.067). In line with our previous finding there was a positive association between prenatal cortisol and negative emotionality in females, and a negative association in males. The interaction between sAA and sex to predict distress was significant (p=0.025), and the direction of effect was the same as for the cortisol data; high sAA associated with increased negative emotionality in females and reduced negative emotionality in males. In line with our previous findings, this research adds to an emerging body of literature, which suggests that fetal programming mechanisms may be sex-dependent. This is the first study to demonstrate that maternal prenatal sAA may be an important biomarker for infant behavior, and the findings have implications for understanding sex differences in developmental psychopathology. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

National Collegiate Athletic Association Division I football players' perceptions of women in the athletic training room using a role congruity framework.

PubMed

O'Connor, Caitlin; Grappendorf, Heidi; Burton, Laura; Harmon, Sandra M; Henderson, Angela C; Peel, Judy

2010-01-01

Previous researchers have demonstrated that male and female athletes feel more comfortable with treatment by a same-sex athletic trainer for sex-specific injuries and conditions. To address football players' comfort with care provided by same-sex and opposite-sex athletic trainers for sex-specific and non-sex-specific injuries and conditions through the lens of role congruity theory. Cross-sectional study for the quantitative data and qualitative study for the qualitative data. Two National Collegiate Athletic Association Division I Football Bowl Series university football programs. Male football players within the 2 university programs. We replicated existing methods and an existing survey to address male football players' comfort levels. Additionally, an open-ended question was used to determine male football players' perceptions of female athletic trainers. Paired-samples t tests were conducted to identify differences between the responses for the care given by a male athletic trainer and for the care given by a female athletic trainer. Three categories were analyzed: general medical conditions, psychological conditions, and sex-specific injuries. The qualitative data were coded and analyzed using content analysis. Male football players were more comfortable with treatment by a male athletic trainer (mean = 3.61 +/- 1.16) for sex-specific injuries and conditions than they were with treatment by a female athletic trainer (mean = 2.82 +/- 1.27; P < .001). No significant results were found for comfort with overall psychological conditions, although a female athletic trainer was preferred over a male athletic trainer for the treatment of depression (mean = 3.71 +/- 1.07 versus mean = 3.39 +/- 1.16, respectively; P < .001). Qualitative data provided support for role congruity theory. Both quantitative and qualitative evidence were provided for the support of role congruity theory.

Sex Differences in Vestibular/Ocular and Neurocognitive Outcomes After Sport-Related Concussion.

PubMed

Sufrinko, Alicia M; Mucha, Anne; Covassin, Tracey; Marchetti, Greg; Elbin, R J; Collins, Michael W; Kontos, Anthony P

2017-03-01

To examine sex differences in vestibular and oculomotor symptoms and impairment in athletes with sport-related concussion (SRC). The secondary purpose was to replicate previously reported sex differences in total concussion symptoms, and performance on neurocognitive and balance testing. Prospective cross-sectional study of consecutively enrolled clinic patients within 21 days of a SRC. Specialty Concussion Clinic. Included male (n = 36) and female (n = 28) athletes ages 9 to 18 years. Vestibular symptoms and impairment was measured with the Vestibular/Ocular Motor Screening (VOMS). Participants completed the Immediate Post-concussion Assessment and Cognitive Test (ImPACT), Post-concussion Symptom Scale (PCSS), and Balance Error Scoring System (BESS). Sex differences on clinical measures. Females had higher PCSS scores (P = 0.01) and greater VOMS vestibular ocular reflex (VOR) score (P = 0.01) compared with males. There were no sex differences on BESS or ImPACT. Total PCSS scores together with female sex accounted for 45% of the variance in VOR scores. Findings suggest higher VOR scores after SRC in female compared with male athletes. Findings did not extend to other components of the VOMS tool suggesting that sex differences may be specific to certain types of vestibular impairment after SRC. Additional research on the clinical significance of the current findings is needed.

Unraveling sexual associations in contact and noncontact child sex offenders using the single category - implicit association test.

PubMed

Hempel, I S; Buck, N M L; Goethals, K R; van Marle, H J C

2013-10-01

Previous studies found associations between children and sex in child sex offenders (CSOs) using the Implicit Association Test (IAT). We used a modification of this task, the Single Category-Implicit Association Test (SC-IAT) to unravel child-sex associations in CSOs. Using the SC-IAT, we were able to test whether CSOs indeed hold stronger child-sex associations relative to adult-sex associations, compared to adult sex offenders and nonoffenders. Furthermore, we examined whether contact CSOs differed from noncontact CSOs in their child-sex associations. The hypothesis that CSOs would have stronger child-sex associations, relative to their adult-sex associations, than adult sex offenders and nonoffenders was confirmed. No difference between contact CSOs and noncontact CSOs was found. Although the Sex SC-IAT was able to distinguish CSOs from nonoffenders, the sensitivity and specificity of the test was poor (AUC of .65) and needs refinement. The results of this study support the existence of a child-sex association as a distinctive characteristic of CSOs. These findings are discussed in the context of theories on deviant cognitions in CSOs and risk for sexual offending.

Functional characterization of sex pheromone receptors in the purple stem borer, Sesamia inferens (Walker).

PubMed

Zhang, Y-N; Zhang, J; Yan, S-W; Chang, H-T; Liu, Y; Wang, G-R; Dong, S-L

2014-10-01

The sex pheromone communication system in moths is highly species-specific and extremely sensitive, and pheromone receptors (PRs) are thought to be the most important factors in males. In the present study, three full-length cDNAs encoding PRs were characterized from Sesamia inferens antennae. These three PRs were all male-specific in expression, but their relative expression levels were very different; SinfOR29 was 17- to 23-fold higher than the other two PRs. Phylogenetic and motif pattern analyses showed that these three PRs were allocated to different PR subfamilies with different motif patterns. Functional analysis using the heterologous expression system of Xenopus oocytes demonstrated that SinfOR29 specifically and sensitively responded to the major pheromone component, Z11-16:OAc [concentration for 50% of maximal effect (EC50 ) = 3.431 × 10(-7) M], while SinfOR21 responded robustly to a minor pheromone component Z11-16:OH (EC50  = 1.087 × 10(-6) M). SinfOR27, however, displayed no response to any of the three pheromone components, but, interestingly, it was sensitive to a non-sex pheromone component Z9,E12-14:OAc (EC50  = 1.522 × 10(-6) M). Our results provide insight into the molecular mechanisms of specificity and sensitivity of the sex pheromone communication system in moths. © 2014 The Royal Entomological Society.

Secondary Growth and Carbohydrate Storage Patterns Differ between Sexes in Juniperus thurifera

PubMed Central

DeSoto, Lucía; Olano, José M.; Rozas, Vicente

2016-01-01

Differences in reproductive costs between male and female plants have been shown to foster sex-related variability in growth and C-storage patterns. The extent to which differential secondary growth in dioecious trees is associated with changes in stem carbohydrate storage patterns, however, has not been fully assessed. We explored the long-term radial growth and the seasonal variation of non-structural carbohydrate (NSC) content in sapwood of 40 males and 40 females Juniperus thurifera trees at two sites. NSC content was analyzed bimonthly for 1 year, and tree-ring width was measured for the 1931–2010 period. Sex-related differences in secondary growth and carbohydrate storage were site-dependent. Under less restrictive environmental conditions females grew more and stored more non-soluble sugars than males. Our results reinforce that sex-related differences in growth and resource storage may be a consequence of local adaptation to environmental conditions. Seasonal variation in soluble sugars concentration was opposite to cambial activity, with minima seen during periods of maximal secondary growth, and did not differ between the sexes or sites. Trees with higher stem NSC levels at critical periods showed higher radial growth, suggesting a common mechanism irrespective of site or sex. Sex-related patterns of secondary growth were linked to differences in non-soluble sugars content indicating sex-specific strategies of long-term performance. PMID:27303418

Origin and domestication of papaya Yh chromosome

USDA-ARS?s Scientific Manuscript database

Sex in papaya is controlled by a pair of nascent sex chromosomes. Females are XX, and two slightly different Y chromosomes distinguish males (XY) and hermaphrodites (XYh). The hermaphrodite-specific region of the Yh chromosome (HSY) and its X chromosome counterpart were sequenced and analyzed previo...

Focus on sex differences in grant applications submitted to the Netherlands Organization for Health Research and Development.

PubMed

Keuken, Debby G; Haafkens, Joke A; Klazinga, Niek S

2007-10-24

Several measures have been implemented at international level to ensure that there is a greater focus on sex differences in health research. This study evaluates the effect of various formal incentives that were introduced by a Dutch financer of health research to encourage applicants to include sex differences in research proposals. We sampled 213 health research proposals submitted in 2003 to the programmes Prevention (N = 104) and Innovation (N = 109) by the Netherlands Organization for Health Research and Development (ZonMw). These proposals were analysed and categorized with regard to the expressed intention to take sex differences into consideration. Furthermore, those proposals in which such intention was absent were appraised by researchers to determine whether an intention of this kind would have been relevant. We found that 23 % of proposals submitted to Prevention (incentive: programme specific instructions) and 10% of those submitted to Innovation (general set of guidelines) took account of sex differences (difference 13%; 95% CI: 3.1-22.9). Conversely, 66% of the research proposals in Prevention, and 20% in Innovation, failed to take sex differences into consideration, even though this might well have been relevant. There is still insufficient incentive for those submitting research proposals to ZonMw to systematically incorporate sex differences when drafting such documents. The provisions in ZonMw's policy need to be amended and better monitored. For this, we formulated some recommendations.

Sex differences in Parkinson's disease.

PubMed

Gillies, Glenda E; Pienaar, Ilse S; Vohra, Shiv; Qamhawi, Zahi

2014-08-01

Parkinson's disease (PD) displays a greater prevalence and earlier age at onset in men. This review addresses the concept that sex differences in PD are determined, largely, by biological sex differences in the NSDA system which, in turn, arise from hormonal, genetic and environmental influences. Current therapies for PD rely on dopamine replacement strategies to treat symptoms, and there is an urgent, unmet need for disease modifying agents. As a significant degree of neuroprotection against the early stages of clinical or experimental PD is seen, respectively, in human and rodent females compared with males, a better understanding of brain sex dimorphisms in the intact and injured NSDA system will shed light on mechanisms which have the potential to delay, or even halt, the progression of PD. Available evidence suggests that sex-specific, hormone-based therapeutic agents hold particular promise for developing treatments with optimal efficacy in men and women. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

"We are Two of the Lucky Ones": Experiences with Marriage and Wellbeing for Same-Sex Couples.

PubMed

Kennedy, Heather R; Dalla, Rochelle L; Dreesman, Steven

2018-01-01

Happy marriages provide protective health benefits, and social support is a key factor in this association. However, previous research indicates one of the greatest differences between same- and different-sex couples is less social support for same-sex couples. Our goal was to examine the extent to which formal markers of couple status (e.g., marriage) impact wellbeing among same-sex married partners. Using a mixed-methods approach, data were collected from 218 primarily White gay and lesbian individuals in the Midwest. Quantitative analysis revealed individuals in a prior formal union with a different-sex partner reported the lowest levels of sexuality specific social support and acceptance. Qualitative analysis revealed four primary impacts of marriage on support from family, friends, and co-workers: no change, increased support, decreased support, and a synthesis of mixed support. Three mechanisms prompting change in the family were identified and are presented.

An examination of sex differences in the effects of early-life opiate and alcohol exposure

PubMed Central

Terasaki, Laurne S.; Gomez, Julie; Schwarz, Jaclyn M.

2016-01-01

Early-life exposure to drugs and alcohol is one of the most preventable causes of developmental, behavioural and learning disorders in children. Thus a significant amount of basic, animal and human research has focused on understanding the behavioural consequences and the associated neural effects of exposure to drugs and alcohol during early brain development. Despite this, much of the previous research that has been done on this topic has used predominantly male subjects or rodents. While many of the findings from these male-specific studies may ultimately apply to females, the purpose of this review is to highlight the research that has also examined sex as a factor and found striking differences between the sexes in their response to early-life opiate and alcohol exposure. Finally, we will also provide a framework for scientists interested in examining sex as a factor in future experiments that specifically examine the consequences of early-life drug and alcohol exposure. PMID:26833841

Sex-specific neural circuits of emotion regulation in the centromedial amygdala.

PubMed

Wu, Yan; Li, Huandong; Zhou, Yuan; Yu, Jian; Zhang, Yuanchao; Song, Ming; Qin, Wen; Yu, Chunshui; Jiang, Tianzi

2016-03-23

Sex-related differences in emotion regulation (ER) in the frequency power distribution within the human amygdala, a brain region involved in emotion processing, have been reported. However, how sex differences in ER are manifested in the brain networks which are seeded on the amygdala subregions is unclear. The goal of this study was to investigate this issue from a brain network perspective. Utilizing resting-state functional connectivity (RSFC) analysis, we found that the sex-specific functional connectivity patterns associated with ER trait level were only seeded in the centromedial amygdala (CM). Women with a higher trait-level ER had a stronger negative RSFC between the right CM and the medial superior frontal gyrus (mSFG), and stronger positive RSFC between the right CM and the anterior insula (AI) and the superior temporal gyrus (STG). But men with a higher trait-level ER was associated with weaker negative RSFC of the right CM-mSFG and positive RSFCs of the right CM-left AI, right CM-right AI/STG, and right CM-left STG. These results provide evidence for the sex-related effects in ER based on CM and indicate that men and women may differ in the neural circuits associated with emotion representation and integration.

Mental health, suicidal ideation, and related factors among workers from medium-sized business establishments in northern Japan: comparative study of sex differences.

PubMed

Takusari, Eri; Suzuki, Mitsuru; Nakamura, Hikaru; Otsuka, Kotaro

2011-01-01

A questionnaire survey was conducted among 3,233 workers (2,442 males and 791 females) from 17 medium-sized business establishments in northern Japan with respect to GHQ-12 score, suicidal ideation, sociodemographic characteristics, work-associated factors, and attitude toward mental health resources. Sex differences were assessed for each questionnaire item, and logistic regression analyses were performed separately for males and females. Significant correlations between common mental disorder (CMD: GHQ-12 score≥3) and the following factors were found for both sexes: short sleep, irregular working schedule, working in specific businesses, and attitude toward mental health resources. Associations between CMD and excess workload were significant only in male workers. While correlations between suicidal ideation and demand for mental health resources were observed in both sexes, significant correlations were observed between suicidal ideation and use of mental health resources for female workers alone. These results suggest that screening of a high-risk population and provision of mental health resources contribute to suicide prevention as a part of mental health promotion measures in medium-sized business establishments. They also suggest the need for identification of business/job type-specific stressors while considering sex differences in lifestyle factors, working environment, and help-seeking behavior.

Associations of Early and Late Gestational Weight Gain with Infant Birth Size.

PubMed

Wander, Pandora L; Sitlani, Colleen M; Badon, Sylvia E; Siscovick, David S; Williams, Michelle A; Enquobahrie, Daniel A

2015-11-01

Associations of gestational weight gain (GWG) during specific periods of pregnancy with infant birth size have been inconsistent. Infant sex-specific differences in these associations are unknown Information on GWG (kg) [total, early (<20 weeks gestation), and late (≥20 weeks gestation)] and indices of infant birth size including birthweight (BW), ponderal index (PI), crown-heel length (CHL), and head circumference (HC) was collected from 3,621 pregnant women. We calculated adjusted mean differences and 95 % confidence intervals (CIs) relating total, early and late GWG to infant birth size using multivariable linear regression procedures. We used stratified analyses and interaction terms to test whether associations differed by infant sex. One-kg increases in total, early or late GWG were associated with BW increases of 17.2 g (95 % CI 13.8-18.9), 14.1 g (95 % CI 10.3-18.0), and 21.0 g (95 % CI 16.7-25.4), respectively. Early GWG-BW and late GWG-BW associations were different (p = 0.026). Sex-stratified total GWG-BW associations were similar to overall results. There were sex-specific differences in early GWG-BW and late GWG-BW associations. Among females, early GWG-BW (12.0 g, 95 % CI 6.7-17.2) and late GWG-BW (24.2 g, 95 % CI 18.2-30.3) associations differed (p = 0.0042); the corresponding associations did not differ among males. Total, early, and late GWG were associated with CHL and HC, but not with PI. Associations did not differ for early or late GWG. For comparable GWG, late-GWG-related BW increase is greater than early-GWG-related BW increase, particularly among female infants.

Does sex influence the diagnostic evaluation of autism spectrum disorder in adults?

PubMed

Wilson, C Ellie; Murphy, Clodagh M; McAlonan, Grainne; Robertson, Dene M; Spain, Debbie; Hayward, Hannah; Woodhouse, Emma; Deeley, P Quinton; Gillan, Nicola; Ohlsen, J Chris; Zinkstok, Janneke; Stoencheva, Vladimira; Faulkner, Jessica; Yildiran, Hatice; Bell, Vaughan; Hammond, Neil; Craig, Michael C; Murphy, Declan Gm

2016-10-01

It is unknown whether sex influences the diagnostic evaluation of autism spectrum disorder, or whether male and female adults within the spectrum have different symptom profiles. This study reports sex differences in clinical outcomes for 1244 adults (935 males and 309 females) referred for autism spectrum disorder assessment. Significantly, more males (72%) than females (66%) were diagnosed with an autism spectrum disorder of any subtype (x(2) = 4.09; p = 0.04). In high-functioning autism spectrum disorder adults (IQ > 70; N = 827), there were no significant sex differences in severity of socio-communicative domain symptoms. Males had significantly more repetitive behaviours/restricted interests than females (p = 0.001, d = 0.3). A multivariate analysis of variance indicated a significant interaction between autism spectrum disorder subtype (full-autism spectrum disorder/partial-autism spectrum disorder) and sex: in full-autism spectrum disorder, males had more severe socio-communicative symptoms than females; for partial-autism spectrum disorder, the reverse was true. There were no sex differences in prevalence of co-morbid psychopathologies. Sex influenced diagnostic evaluation in a clinical sample of adults with suspected autism spectrum disorder. The sexes may present with different manifestations of the autism spectrum disorder phenotype and differences vary by diagnostic subtype. Understanding and awareness of adult female repetitive behaviours/restricted interests warrant attention and sex-specific diagnostic assessment tools may need to be considered. © The Author(s) 2016.

Does sex influence the diagnostic evaluation of autism spectrum disorder in adults?

PubMed Central

Wilson, C Ellie; Murphy, Clodagh M; McAlonan, Grainne; Robertson, Dene M; Spain, Debbie; Hayward, Hannah; Woodhouse, Emma; Deeley, P Quinton; Gillan, Nicola; Ohlsen, J Chris; Zinkstok, Janneke; Stoencheva, Vladimira; Faulkner, Jessica; Yildiran, Hatice; Bell, Vaughan; Hammond, Neil; Craig, Michael C; Murphy, Declan GM

2016-01-01

It is unknown whether sex influences the diagnostic evaluation of autism spectrum disorder, or whether male and female adults within the spectrum have different symptom profiles. This study reports sex differences in clinical outcomes for 1244 adults (935 males and 309 females) referred for autism spectrum disorder assessment. Significantly, more males (72%) than females (66%) were diagnosed with an autism spectrum disorder of any subtype (x2 = 4.09; p = 0.04). In high-functioning autism spectrum disorder adults (IQ > 70; N = 827), there were no significant sex differences in severity of socio-communicative domain symptoms. Males had significantly more repetitive behaviours/restricted interests than females (p = 0.001, d = 0.3). A multivariate analysis of variance indicated a significant interaction between autism spectrum disorder subtype (full-autism spectrum disorder/partial-autism spectrum disorder) and sex: in full-autism spectrum disorder, males had more severe socio-communicative symptoms than females; for partial-autism spectrum disorder, the reverse was true. There were no sex differences in prevalence of co-morbid psychopathologies. Sex influenced diagnostic evaluation in a clinical sample of adults with suspected autism spectrum disorder. The sexes may present with different manifestations of the autism spectrum disorder phenotype and differences vary by diagnostic subtype. Understanding and awareness of adult female repetitive behaviours/restricted interests warrant attention and sex-specific diagnostic assessment tools may need to be considered. PMID:26802113

Conservation of sex chromosomes in lacertid lizards.

PubMed

Rovatsos, Michail; Vukić, Jasna; Altmanová, Marie; Johnson Pokorná, Martina; Moravec, Jiří; Kratochvíl, Lukáš

2016-07-01

Sex chromosomes are believed to be stable in endotherms, but young and evolutionary unstable in most ectothermic vertebrates. Within lacertids, the widely radiated lizard group, sex chromosomes have been reported to vary in morphology and heterochromatinization, which may suggest turnovers during the evolution of the group. We compared the partial gene content of the Z-specific part of sex chromosomes across major lineages of lacertids and discovered a strong evolutionary stability of sex chromosomes. We can conclude that the common ancestor of lacertids, living around 70 million years ago (Mya), already had the same highly differentiated sex chromosomes. Molecular data demonstrating an evolutionary conservation of sex chromosomes have also been documented for iguanas and caenophidian snakes. It seems that differences in the evolutionary conservation of sex chromosomes in vertebrates do not reflect the distinction between endotherms and ectotherms, but rather between amniotes and anamniotes, or generally, the differences in the life history of particular lineages. © 2016 John Wiley & Sons Ltd.

Perinatal BPA exposure alters body weight and composition in a dose specific and sex specific manner: The addition of peripubertal exposure exacerbates adverse effects in female mice.

PubMed

Rubin, Beverly S; Paranjpe, Maneesha; DaFonte, Tracey; Schaeberle, Cheryl; Soto, Ana M; Obin, Martin; Greenberg, Andrew S

2017-03-01

Body weight (BW) and body composition were examined in CD-1 mice exposed perinatally or perinatally and peripubertally to 0, 0.25, 2.5, 25, or 250μg BPA/kg BW/day. Our goal was to identify the BPA dose (s) and the exposure window(s) that increased BW and adiposity, and to assess potential sex differences in this response. Both perinatal exposure alone and perinatal plus peripubertal exposure to environmentally relevant levels of BPA resulted in lasting effects on body weight and body composition. The effects were dose specific and sex specific and were influenced by the precise window of BPA exposure. The addition of peripubertal BPA exposure following the initial perinatal exposure exacerbated adverse effects in the females but appeared to reduce differences in body weight and body composition between control and BPA exposed males. Some effects of BPA on body weight and body composition showed a non-linear dose response. Copyright © 2016. Published by Elsevier Inc.

The political economy of urban homicide: assessing the relative impact of gender inequality on sex-specific victimization.

PubMed

DeWees, Mari A; Parker, Karen F

2003-02-01

This research examines the ways in which the changing political economy of urban areas has contributed differently to the homicide victimization rates of females and males across US cities. Recent research, while relatively limited, has presented disparate results regarding the effect of gender inequality on urban sex-specific victimization. Our work further explores this relationship by taking into account relative gender disparities in income, education, labor market opportunities, and politics in an examination of sex-specific homicide victimization in 1990. Key to this current investigation is the evaluation of feminist and lifestyle arguments that suggest that structural gender inequality has a unique effect on female victimization. Overall, our findings reveal gender inequality to be a significant predictor of both male and female urban homicide. While these findings suggest mixed support for theoretical arguments regarding gender inequality, further analyses reveal significant differences in specific types of gender inequality on victimization patterns across genders. These additional results highlight the need for greater attention toward both methodological and theoretical issues when examining the interconnections between gender, political economy, and violence in research.

Differences in Work-Related Adverse Events by Sex and Industry in Cases Involving Compensation for Mental Disorders and Suicide in Japan From 2010 to 2014.

PubMed

Yamauchi, Takashi; Sasaki, Takeshi; Yoshikawa, Toru; Matsumoto, Shun; Takahashi, Masaya; Suka, Machi; Yanagisawa, Hiroyuki

2018-04-01

This study aimed to clarify whether work-related adverse events in cases involving compensation for mental disorders and suicide differ by sex and industry using a database containing all relevant cases reported from 2010 to 2014 in Japan. A total of 1362 eligible cases involving compensation for mental disorders (422 females and 940 males) were analyzed. Among males, 55.7% of cases were attributed to "long working hours." In both sexes, the frequencies of cases attributed to "long working hours" and other events differed significantly by industry. Among cases involving compensation for suicide, 71.4% were attributed to "long working hours." The frequency distribution of work-related adverse events differed significantly by sex and industry. These differences should be taken into consideration in the development of industry-specific preventive measures for occupational mental disorders.

Sociocultural facilitators and barriers to condom use during anal sex among men who have sex with men in Guangzhou, China: an ethnographic study.

PubMed

Li, Haochu; Lau, Joseph T F; Holroyd, Eleanor; Yi, Huso

2010-12-01

This ethnographic study explored how cultural belief systems shaped sexual risk practices among men who have sex with men (MSM) in Guangzhou, China. A specific focus was on how these men's sexual practices varied across sexual venues and among different partners in order to better understand sociocultural facilitators and barriers to condom use in the Guangzhou community. Qualitative data were obtained through semi-structured in-depth interviews with MSM and ethnographic observations in MSM sexual venues in the city. The thematic analysis focused specifically on the accounts of unprotected sex occasions. We found that an erotic idea of "rouyu" (desire of physical flesh) embedded in a subculture of MSM and a metaphor for condom use as being inferior and promoting distance posed a considerable barrier to condom use among these MSM. Some men reported gaining a positive self-concept related to same-sex identity through unprotected sex. These MSM's subjective evaluations of HIV risk were closely tied to the perceived characteristics of sex partners and sexual venues. We conclude by advocating specific sociocultural interventions in emerging risk venues, such as saunas/bathhouses, to better meet the needs of the MSM community in Guangzhou.

Mates but not sexes differ in migratory niche in a monogamous penguin species.

PubMed

Thiebot, Jean-Baptiste; Bost, Charles-André; Dehnhard, Nina; Demongin, Laurent; Eens, Marcel; Lepoint, Gilles; Cherel, Yves; Poisbleau, Maud

2015-09-01

Strong pair bonds generally increase fitness in monogamous organisms, but may also underlie the risk of hampering it when re-pairing fails after the winter season. We investigated whether partners would either maintain contact or offset this risk by exploiting sex-specific favourable niches during winter in a migratory monogamous seabird, the southern rockhopper penguin Eudyptes chrysocome. Using light-based geolocation, we show that although the spatial distribution of both sexes largely overlapped, pair-wise mates were located on average 595 ± 260 km (and up to 2500 km) apart during winter. Stable isotope data also indicated a marked overlap between sex-specific isotopic niches (δ¹³C and δ¹⁵N values) but a segregation of the feeding habitats (δ¹³C values) within pairs. Importantly, the tracked females remained longer (12 days) at sea than males, but all re-mated with their previous partners after winter. Our study provides multiple evidence that migratory species may well demonstrate pair-wise segregation even in the absence of sex-specific winter niches (spatial and isotopic). We suggest that dispersive migration patterns with sex-biased timings may be a sufficient proximal cause for generating such a situation in migratory animals.

Association of Sex With the Global Burden of Cataract.

PubMed

Lou, Lixia; Ye, Xin; Xu, Peifang; Wang, Jingyi; Xu, Yufeng; Jin, Kai; Ye, Juan

2018-02-01

Eye disease burden could help guide health policy making. Differences in cataract burden by sex is a major concern of reducing avoidable blindness caused by cataract. To investigate the association of sex with the global burden of cataract by year, age, and socioeconomic status using disability-adjusted life-years (DALYs). This international, comparative burden-of-disease study extracted the global, regional, and national sex-specific DALY numbers, crude DALY rates, and age-standardized DALY rates caused by cataract by year and age from the Global Burden of Disease Study 2015. The DALY data were collected from January 1, 1990, through December 31, 2015, for ever 5 years. The human development index (HDI) in 2015 was extracted as an indicator of national socioeconomic status from the Human Development Report. Comparisons of sex-specific DALY estimates due to cataract by year, age, and socioeconomic status at the global level. Paired Wilcoxon signed rank test, Pearson correlation, and linear regression analyses were performed to evaluate the socioeconomic-associated sex differences in cataract burden. Differences in rates of cataract by sex were similar between 1990 and 2015, with age-standardized DALY rates of 54.5 among men vs 65.0 among women in 1990 and 52.3 among men vs 67.0 among women in 2015. Women had higher rates than men of the same age, and sexual differences increased with age. Paired Wilcoxon signed rank test revealed that age-standardized DALY rates among women were higher than those among men for each HDI-based country group (z range, -4.236 to -6.093; P < .001). The difference (female minus male) in age-standardized DALY rates (r = -0.610 [P < .001]; standardized β = -0.610 [P < .001]) and the female to male age-standardized DALY rate ratios (r = -0.180 [P = .02]; standardized β = -0.180 [P = .02]) were inversely correlated with HDI. Although global cataract health care is progressing, sexual differences in cataract burden showed little improvement in the past few decades. Worldwide, women have a higher cataract burden than men. Older age and lower socioeconomic status are associated with greater differences in rates of cataract by sex. Our findings may enhance public awareness of sexual differences in global cataract burden and emphasize the importance of making sex-sensitive health policy to manage global vision loss caused by cataract.

Sex difference in the principal cytochrome P-450 for tributyltin metabolism in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohhira, Shuji; Enomoto, Mitsunori; Matsui, Hisao

Tributyltin is metabolized by cytochrome P-450 (CYP) system enzymes, and its metabolic fate may contribute to the toxicity of the chemical. In the present study, it is examined whether sex differences in the metabolism of tributyltin exist in rats. In addition, the in vivo and in vitro metabolism of tributyltin was investigated using rat hepatic CYP systems to confirm the principal CYP involved. A significant sex difference in metabolism occurred both in vivo and in vitro, suggesting that one of the CYPs responsible for tributyltin metabolism in rats is male specific or predominant at least. Eight cDNA-expressed rat CYPs, includingmore » typical phenobarbital (PB)-inducible forms and members of the CYP2C subfamily, were tested to determine their capability for tributyltin metabolism. Among the enzymes studied, a statistically significant dealkylation of tributyltin was mediated by CYP2C6 and 2C11. Furthermore, the sex difference in metabolism disappeared in vitro after anti-rat CYP2C11 antibody pretreatment because CYP2C11 is a major male-specific form in rats. These results indicate that CYP2C6 is the principal CYP for tributyltin metabolism in female rats, whereas CYP2C11 as well as 2C6 is involved in tributyltin metabolism in male rats, and it is suggested that CYP2C11 is responsible for the significant sex difference in the metabolism of tributyltin observed in rats.« less

Sexually divergent induction of microglial-associated neuroinflammation with hippocampal aging.

PubMed

Mangold, Colleen A; Wronowski, Benjamin; Du, Mei; Masser, Dustin R; Hadad, Niran; Bixler, Georgina V; Brucklacher, Robert M; Ford, Matthew M; Sonntag, William E; Freeman, Willard M

2017-07-21

The necessity of including both males and females in molecular neuroscience research is now well understood. However, there is relatively limited basic biological data on brain sex differences across the lifespan despite the differences in age-related neurological dysfunction and disease between males and females. Whole genome gene expression of young (3 months), adult (12 months), and old (24 months) male and female C57BL6 mice hippocampus was analyzed. Subsequent bioinformatic analyses and confirmations of age-related changes and sex differences in hippocampal gene and protein expression were performed. Males and females demonstrate both common expression changes with aging and marked sex differences in the nature and magnitude of the aging responses. Age-related hippocampal induction of neuroinflammatory gene expression was sexually divergent and enriched for microglia-specific genes such as complement pathway components. Sexually divergent C1q protein expression was confirmed by immunoblotting and immunohistochemistry. Similar patterns of cortical sexually divergent gene expression were also evident. Additionally, inter-animal gene expression variability increased with aging in males, but not females. These findings demonstrate sexually divergent neuroinflammation with aging that may contribute to sex differences in age-related neurological diseases such as stroke and Alzheimer's, specifically in the complement system. The increased expression variability in males suggests a loss of fidelity in gene expression regulation with aging. These findings reveal a central role of sex in the transcriptomic response of the hippocampus to aging that warrants further, in depth, investigations.

Meta-analysis of sex-specific genome-wide association studies.

PubMed

Magi, Reedik; Lindgren, Cecilia M; Morris, Andrew P

2010-12-01

Despite the success of genome-wide association studies, much of the genetic contribution to complex human traits is still unexplained. One potential source of genetic variation that may contribute to this "missing heritability" is that which differs in magnitude and/or direction between males and females, which could result from sexual dimorphism in gene expression. Such sex-differentiated effects are common in model organisms, and are becoming increasingly evident in human complex traits through large-scale male- and female-specific meta-analyses. In this article, we review the methodology for meta-analysis of sex-specific genome-wide association studies, and propose a sex-differentiated test of association with quantitative or dichotomous traits, which allows for heterogeneity of allelic effects between males and females. We perform detailed simulations to compare the power of the proposed sex-differentiated meta-analysis with the more traditional "sex-combined" approach, which is ambivalent to gender. The results of this study highlight only a small loss in power for the sex-differentiated meta-analysis when the allelic effects of the causal variant are the same in males and females. However, over a range of models of heterogeneity in allelic effects between genders, our sex-differentiated meta-analysis strategy offers substantial gains in power, and thus has the potential to discover novel loci contributing effects to complex human traits with existing genome-wide association data. © 2010 Wiley-Liss, Inc.

Sex and gender differences in substance use disorders.

PubMed

McHugh, R Kathryn; Votaw, Victoria R; Sugarman, Dawn E; Greenfield, Shelly F

2017-11-10

The gender gap in substance use disorders (SUDs), characterized by greater prevalence in men, is narrowing, highlighting the importance of understanding sex and gender differences in SUD etiology and maintenance. In this critical review, we provide an overview of sex/gender differences in the biology, epidemiology and treatment of SUDs. Biological sex differences are evident across an array of systems, including brain structure and function, endocrine function, and metabolic function. Gender (i.e., environmentally and socioculturally defined roles for men and women) also contributes to the initiation and course of substance use and SUDs. Adverse medical, psychiatric, and functional consequences associated with SUDs are often more severe in women. However, men and women do not substantively differ with respect to SUD treatment outcomes. Although several trends are beginning to emerge in the literature, findings on sex and gender differences in SUDs are complicated by the interacting contributions of biological and environmental factors. Future research is needed to further elucidate sex and gender differences, especially focusing on hormonal factors in SUD course and treatment outcomes; research translating findings between animal and human models; and gender differences in understudied populations, such as those with co-occurring psychiatric disorders and gender-specific populations, such as pregnant women. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sex-specific differences in the presenting location of a first venous thromboembolism.

PubMed

Scheres, L J J; Brekelmans, M P A; Beenen, L F M; Büller, H R; Cannegieter, S C; Middeldorp, S

2017-07-01

Essentials Whether the location of venous thromboembolism (VTE) differs between the sexes is not known. Pulmonary embolism as presenting location was relatively more common in women than in men. The difference was consistent among age groups and most prominent in unprovoked VTE. The underlying mechanism remains to be elucidated. Background The risk of venous thromboembolism (VTE) differs between men and women. Some risk factors seem to influence the presenting location of VTE. Sex-specific differences in the presenting VTE location have not been studied extensively. Methods We analyzed data from the MEGA case-control study and the Hokusai-VTE study, and used published data from the RIETE registry. Data from patients with a symptomatic first VTE were included (MEGA, n = 4953; Hokusai-VTE, n = 6720; RIETE, n = 40 028). Distributions of deep vein thrombosis (DVT), pulmonary embolism (PE) and combined DVT and PE as the presenting VTE location were calculated for men and women, and presented as proportions with 95% confidence intervals (CIs). Sex-specific differences were explored for different age categories and for unprovoked and provoked events. Results In the MEGA study, PE was the presenting location in 35.5% of women and in 29.5% of men with VTE (difference 6.0%, 95% CI 3.4-8.6). In the Hokusai-VTE study, these proportions were 35.1% for women and 25.2% for men (difference 10.0%, 95% CI 7.8-12.2). In the RIETE registry, PE (with or without DVT) was also observed more often as the presenting location in women (53.3%) than in men (47.7%), with a difference of 5.6% (95% CI 4.7-6.6). The observed higher proportion of PE as the presenting location in women was present in all age groups and was most prominent among unprovoked VTE events. Conclusions In three large studies, the distribution of the presenting VTE location differed consistently between the sexes, whereby PE was more often the primary location of presentation in women than in men. © 2017 International Society on Thrombosis and Haemostasis.

Adaptive attunement of selective covert attention to evolutionary-relevant emotional visual scenes.

PubMed

Fernández-Martín, Andrés; Gutiérrez-García, Aída; Capafons, Juan; Calvo, Manuel G

2017-05-01

We investigated selective attention to emotional scenes in peripheral vision, as a function of adaptive relevance of scene affective content for male and female observers. Pairs of emotional-neutral images appeared peripherally-with perceptual stimulus differences controlled-while viewers were fixating on a different stimulus in central vision. Early selective orienting was assessed by the probability of directing the first fixation towards either scene, and the time until first fixation. Emotional scenes selectively captured covert attention even when they were task-irrelevant, thus revealing involuntary, automatic processing. Sex of observers and specific emotional scene content (e.g., male-to-female-aggression, families and babies, etc.) interactively modulated covert attention, depending on adaptive priorities and goals for each sex, both for pleasant and unpleasant content. The attentional system exhibits domain-specific and sex-specific biases and attunements, probably rooted in evolutionary pressures to enhance reproductive and protective success. Emotional cues selectively capture covert attention based on their bio-social significance. Copyright © 2017 Elsevier Inc. All rights reserved.

Imaging Sex Differences in Regional Brain Metabolism during Acute Opioid Withdrawal

PubMed Central

Santoro, Giovanni C; Carrion, Joseph; Dewey, Stephen L

2017-01-01

The rate of opioid overdose continues to rise, necessitating improved treatment options. Current therapeutic approaches rely on administration of either a blocking agent, such as naloxone, or chronic treatment with replacement drugs, including methadone and/or buprenorphine. Recent findings suggest that males and females respond to these treatments uniquely. In an effort to better understand this sex-specific variation in treatment efficacy, we investigated the effects of acute opioid withdrawal in male and female rats using 18FDG and microPET. These data demonstrate that acute opioid withdrawal produces metabolic alterations in brain regions associated with reward and drug dependence, namely corpus striatum, thalamic nuclei, septum, and frontal cortex. Furthermore, certain changes are unique to males. Specifically, males demonstrated increased metabolism in the anterior cingulate cortex and the ventral hippocampus (CA3) following acute opioid withdrawal. If males and females exhibit sex-specific changes in regional brain metabolism following acute opioid withdrawal, then perhaps it is not surprising that they respond to treatment differently. PMID:29046888

Experiences of Sex Education and Sexual Awareness in Young Adults with Autism Spectrum Disorder.

PubMed

Hannah, Laura A; Stagg, Steven D

2016-12-01

The research investigated feelings towards sex education and sexual awareness in young adults with autism spectrum disorder (ASD). Data were generated from the sexual knowledge, experiences, feelings and needs questionnaire (McCabe et al. 1999), the sexual awareness questionnaire (Snell et al. 1991) and semi-structured interviews. Twenty typically developing and 20 ASD individuals participated. Feelings toward sex education did not differ between the groups, but the groups differed significantly on measures of sexual awareness. Negative experiences of sex education and issues of vulnerability, social anxiety, and confused sexuality were prominent features of the qualitative interviews. This report suggest that mainstream sex and relationship education is not sufficient for people with ASD, specific methods and curricular are necessary to match their needs.

Sex-specific differences in transcriptome profiles of brain and muscle tissue of the tropical gar.

PubMed

Cribbin, Kayla M; Quackenbush, Corey R; Taylor, Kyle; Arias-Rodriguez, Lenin; Kelley, Joanna L

2017-04-07

The tropical gar (Atractosteus tropicus) is the southernmost species of the seven extant species of gar fishes in the world. In Mexico and Central America, the species is an important food source due to its nutritional quality and low price. Despite its regional importance and increasing concerns about overexploitation and habitat degradation, basic genetic information on the tropical gar is lacking. Determining genetic information on the tropical gar is important for the sustainable management of wild populations, implementation of best practices in aquaculture settings, evolutionary studies of ancient lineages, and an understanding of sex-specific gene expression. In this study, the transcriptome of the tropical gar was sequenced and assembled de novo using tissues from three males and three females using Illumina sequencing technology. Sex-specific and highly differentially expressed transcripts in brain and muscle tissues between adult males and females were subsequently identified. The transcriptome was assembled de novo resulting in 80,611 transcripts with a contig N50 of 3,355 base pairs and over 168 kilobases in total length. Male muscle, brain, and gonad as well as female muscle and brain were included in the assembly. The assembled transcriptome was annotated to identify the putative function of expressed transcripts using Trinotate and SwissProt, a database of well-annotated proteins. The brain and muscle datasets were then aligned to the assembled transcriptome to identify transcripts that were differentially expressed between males and females. The contrast between male and female brain identified 109 transcripts from 106 genes that were significantly differentially expressed. In the muscle comparison, 82 transcripts from 80 genes were identified with evidence for significant differential expression. Almost all genes identified as differentially expressed were sex-specific. The differentially expressed transcripts were enriched for genes involved in cellular functioning, signaling, immune response, and tissue-specific functions. This study identified differentially expressed transcripts between male and female gar in muscle and brain tissue. The majority of differentially expressed transcripts had sex-specific expression. Expanding on these findings to other developmental stages, populations, and species may lead to the identification of genetic factors contributing to the skewed sex ratio seen in the tropical gar and of sex-specific differences in expression in other species. Finally, the transcriptome assembly will open future research avenues on tropical gar development, cell function, environmental resistance, and evolution in the context of other early vertebrates.

Reconceptualizing sex, brain and psychopathology: interaction, interaction, interaction

PubMed Central

Joel, D; Yankelevitch-Yahav, R

2014-01-01

In recent years there has been a growing recognition of the influence of sex on brain structure and function, and in relation, on the susceptibility, prevalence and response to treatment of psychiatric disorders. Most theories and descriptions of the effects of sex on the brain are dominated by an analogy to the current interpretation of the effects of sex on the reproductive system, according to which sex is a divergence system that exerts a unitary, overriding and serial effect on the form of other systems. We shortly summarize different lines of evidence that contradict aspects of this analogy. The new view that emerges from these data is of sex as a complex system whose different components interact with one another and with other systems to affect body and brain. The paradigm shift that this understanding calls for is from thinking of sex in terms of sexual dimorphism and sex differences, to thinking of sex in terms of its interactions with other factors and processes. Our review of data obtained from animal models of psychopathology clearly reveals the need for such a paradigmatic shift, because in the field of animal behaviour whether a sex difference exists and its direction depend on the interaction of many factors including, species, strain, age, specific test employed and a multitude of environmental factors. We conclude by explaining how the new conceptualization can account for sex differences in psychopathology. Linked Articles This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20 PMID:24758640

Differential Risk Factors for HIV Drug and Sex Risk-Taking Among Non-treatment-seeking Hospitalized Injection Drug Users

PubMed Central

Crooks, Denise; Tsui, Judith; Anderson, Bradley; Dossabhoy, Shernaz; Herman, Debra; Liebschutz, Jane M.; Stein, Michael D.

2016-01-01

Injection drug users (IDUs) are at increased risk of contracting HIV. From a clinical trial assessing an intervention to enhance the linkage of hospitalized patients to opioid treatment after discharge, we conducted multivariate analysis of baseline data from hospitalized IDUs with a history of opioid dependence (n = 104) to identify differences in factors predicting HIV drug and sex risk behaviors. Factors significantly associated with HIV drug risk were being non-Hispanic Caucasian and recent cocaine use. Being female, binge drinking, and poorer mental health were significantly associated with higher sex risk. Because factors predicting HIV sex risk behaviors differ from those predicting HIV drug risk, interventions aimed at specific HIV risks should have different behavioral and substance use targets. PMID:25063229

Sex-specific cognitive abnormalities in early-onset psychosis.

PubMed

Ruiz-Veguilla, Miguel; Moreno-Granados, Josefa; Salcedo-Marin, Maria D; Barrigon, Maria L; Blanco-Morales, Maria J; Igunza, Evelio; Cañabate, Anselmo; Garcia, Maria D; Guijarro, Teresa; Diaz-Atienza, Francisco; Ferrin, Maite

2017-01-01

Brain maturation differs depending on the area of the brain and sex. Girls show an earlier peak in maturation of the prefrontal cortex. Although differences between adult females and males with schizophrenia have been widely studied, there has been less research in girls and boys with psychosis. The purpose of this study was to examine differences in verbal and visual memory, verbal working memory, auditory attention, processing speed, and cognitive flexibility between boys and girls. We compared a group of 80 boys and girls with first-episode psychosis to a group of controls. We found interactions between group and sex in verbal working memory (p = 0.04) and auditory attention (p = 0.01). The female controls showed better working memory (p = 0.01) and auditory attention (p = 0.001) than males. However, we did not find any sex differences in working memory (p = 0.91) or auditory attention (p = 0.93) in the psychosis group. These results are consistent with the presence of sex-modulated cognitive profiles at first presentation of early-onset psychosis.

Her versus his migraine: multiple sex differences in brain function and structure

PubMed Central

Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David

2012-01-01

Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional responses to heat within the migraine groups indicated concurrent functional differences in male and female migraineurs and a sex-specific pattern of functional connectivity of these two regions with the rest of the brain. The results support the notion of a ‘sex phenotype’ in migraine and indicate that brains are differentially affected by migraine in females compared with males. Furthermore, the results also support the notion that sex differences involve both brain structure as well as functional circuits, in that emotional circuitry compared with sensory processing appears involved to a greater degree in female than male migraineurs. PMID:22843414

Sex differences in the ability to recognise non-verbal displays of emotion: a meta-analysis.

PubMed

Thompson, Ashley E; Voyer, Daniel

2014-01-01

The present study aimed to quantify the magnitude of sex differences in humans' ability to accurately recognise non-verbal emotional displays. Studies of relevance were those that required explicit labelling of discrete emotions presented in the visual and/or auditory modality. A final set of 551 effect sizes from 215 samples was included in a multilevel meta-analysis. The results showed a small overall advantage in favour of females on emotion recognition tasks (d=0.19). However, the magnitude of that sex difference was moderated by several factors, namely specific emotion, emotion type (negative, positive), sex of the actor, sensory modality (visual, audio, audio-visual) and age of the participants. Method of presentation (computer, slides, print, etc.), type of measurement (response time, accuracy) and year of publication did not significantly contribute to variance in effect sizes. These findings are discussed in the context of social and biological explanations of sex differences in emotion recognition.

Her versus his migraine: multiple sex differences in brain function and structure.

PubMed

Maleki, Nasim; Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David

2012-08-01

Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional responses to heat within the migraine groups indicated concurrent functional differences in male and female migraineurs and a sex-specific pattern of functional connectivity of these two regions with the rest of the brain. The results support the notion of a 'sex phenotype' in migraine and indicate that brains are differentially affected by migraine in females compared with males. Furthermore, the results also support the notion that sex differences involve both brain structure as well as functional circuits, in that emotional circuitry compared with sensory processing appears involved to a greater degree in female than male migraineurs.

The impact of physical activity and sex differences on intraindividual variability in inhibitory performance in older adults.

PubMed

Fagot, Delphine; Chicherio, Christian; Albinet, Cédric T; André, Nathalie; Audiffren, Michel

2017-09-04

It is well-known that processing speed and executive functions decline with advancing age. However, physical activity (PA) has a positive impact on cognitive performances in aging, specifically for inhibition. Less is known concerning intraindividual variability (iiV) in reaction times. This study aims to investigate the influence of PA and sex differences on iiV in inhibitory performance during aging. Healthy adults were divided into active and sedentary groups according to PA level. To analyse iiV in reaction times, individual mean, standard deviation and the ex-Gaussian parameters were considered. An interaction between activity level and sex was revealed, sedentary females being slower and more variable than sedentary men. No sex differences were found in the active groups. These results indicate that the negative impact of sedentariness on cognitive performance in older age is stronger for females. The present findings underline the need to consider sex differences in active aging approaches.

Sex and Class Differences in Parent-Child Interaction: A Test of Kohn's Hypothesis. Scientific Paper No. 4181.

ERIC Educational Resources Information Center

Gecas, Viktor; Nye, F. Ivan

This paper examines sex and class differences in the style and circumstances of parental discipline of the child. Specifically, we have focused on Melvin Kohn's suggestive hypothesis that white collar parents stress the development of internal standards of conduct in their children and thus are more likely to discipline the child on the basis of…

Flower development and sex specification in wild grapevine.

PubMed

Ramos, Miguel Jesus Nunes; Coito, João Lucas; Silva, Helena Gomes; Cunha, Jorge; Costa, Maria Manuela Ribeiro; Rocheta, Margarida

2014-12-12

Wild plants of Vitis closely related to the cultivated grapevine (V. v. vinifera) are believed to have been first domesticated 10,000 years BC around the Caspian Sea. V. v. vinifera is hermaphrodite whereas V. v. sylvestris is a dioecious species. Male flowers show a reduced pistil without style or stigma and female flowers present reflexed stamens with infertile pollen. V. vinifera produce perfect flowers with all functional structures. The mechanism for flower sex determination and specification in grapevine is still unknown. To understand which genes are involved during the establishment of male, female and complete flowers, we analysed and compared the transcription profiles of four developmental stages of the three genders. We showed that sex determination is a late event during flower development and that the expression of genes from the ABCDE model is not directly correlated with the establishment of sexual dimorphism. We propose a temporal comprehensive model in which two mutations in two linked genes could be players in sex determination and indirectly establish the Vitis domestication process. Additionally, we also found clusters of genes differentially expressed between genders and between developmental stages that suggest a role involved in sex differentiation. Also, the detection of differentially transcribed regions that extended existing gene models (intergenic regions) between sexes suggests that they may account for some of the variation between the subspecies. There is no evidence of differences of expression levels in genes from the ABCDE model that could explain the shift from hermaphroditism to dioecy. We propose that sex specification occurs after floral organ identity has been established and therefore, sex determination genes might be having an effect downstream of the ABCDE model genes.For the first time a full transcriptomic analysis was performed in different flower developmental stages in the same individual. Our experimental approach enabled us to create a comprehensive catalogue of transcribed genes across developmental stages and genders that will contribute for future work in sex determination in seed plants.

A novel hypothesis for the adaptive maintenance of environmental sex determination in a turtle.

PubMed

Spencer, R-J; Janzen, F J

2014-08-22

Temperature-dependent sex determination (TSD) is widespread in reptiles, yet its adaptive significance and mechanisms for its maintenance remain obscure and controversial. Comparative analyses identify an ancient origin of TSD in turtles, crocodiles and tuatara, suggesting that this trait should be advantageous in order to persist. Based on this assumption, researchers primarily, and with minimal success, have employed a model to examine sex-specific variation in hatchling phenotypes and fitness generated by different incubation conditions. The unwavering focus on different incubation conditions may be misplaced at least in the many turtle species in which hatchlings overwinter in the natal nest. If overwintering temperatures differentially affect fitness of male and female hatchlings, TSD might be maintained adaptively by enabling embryos to develop as the sex best suited to those overwintering conditions. We test this novel hypothesis using the painted turtle (Chrysemys picta), a species with TSD in which eggs hatch in late summer and hatchlings remain within nests until the following spring. We used a split-clutch design to expose field-incubated hatchlings to warm and cool overwintering (autumn-winter-spring) regimes in the laboratory and measured metabolic rates, energy use, body size and mortality of male and female hatchlings. While overall mortality rates were low, males exposed to warmer overwintering regimes had significantly higher metabolic rates and used more residual yolk than females, whereas the reverse occurred in the cool temperature regime. Hatchlings from mixed-sex nests exhibited similar sex-specific trends and, crucially, they were less energy efficient and grew less than same-sex hatchlings that originated from single-sex clutches. Such sex- and incubation-specific physiological adaptation to winter temperatures may enhance fitness and even extend the northern range of many species that overwinter terrestrially. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Transcriptome Profile Analysis from Different Sex Types of Ginkgo biloba L.

PubMed

Du, Shuhui; Sang, Yalin; Liu, Xiaojing; Xing, Shiyan; Li, Jihong; Tang, Haixia; Sun, Limin

2016-01-01

In plants, sex determination is a comprehensive process of correlated events, which involves genes that are differentially and/or specifically expressed in distinct developmental phases. Exploring gene expression profiles from different sex types will contribute to fully understanding sex determination in plants. In this study, we conducted RNA-sequencing of female and male buds (FB and MB) as well as ovulate strobilus and staminate strobilus (OS and SS) of Ginkgo biloba to gain insights into the genes potentially related to sex determination in this species. Approximately 60 Gb of clean reads were obtained from eight cDNA libraries. De novo assembly of the clean reads generated 108,307 unigenes with an average length of 796 bp. Among these unigenes, 51,953 (47.97%) had at least one significant match with a gene sequence in the public databases searched. A total of 4709 and 9802 differentially expressed genes (DEGs) were identified in MB vs. FB and SS vs. OS, respectively. Genes involved in plant hormone signal and transduction as well as those encoding DNA methyltransferase were found to be differentially expressed between different sex types. Their potential roles in sex determination of G. biloba were discussed. Pistil-related genes were expressed in male buds while anther-specific genes were identified in female buds, suggesting that dioecism in G. biloba was resulted from the selective arrest of reproductive primordia. High correlation of expression level was found between the RNA-Seq and quantitative real-time PCR results. The transcriptome resources that we generated allowed us to characterize gene expression profiles and examine differential expression profiles, which provided foundations for identifying functional genes associated with sex determination in G. biloba.

Transcriptome Profile Analysis from Different Sex Types of Ginkgo biloba L.

PubMed Central

Du, Shuhui; Sang, Yalin; Liu, Xiaojing; Xing, Shiyan; Li, Jihong; Tang, Haixia; Sun, Limin

2016-01-01

In plants, sex determination is a comprehensive process of correlated events, which involves genes that are differentially and/or specifically expressed in distinct developmental phases. Exploring gene expression profiles from different sex types will contribute to fully understanding sex determination in plants. In this study, we conducted RNA-sequencing of female and male buds (FB and MB) as well as ovulate strobilus and staminate strobilus (OS and SS) of Ginkgo biloba to gain insights into the genes potentially related to sex determination in this species. Approximately 60 Gb of clean reads were obtained from eight cDNA libraries. De novo assembly of the clean reads generated 108,307 unigenes with an average length of 796 bp. Among these unigenes, 51,953 (47.97%) had at least one significant match with a gene sequence in the public databases searched. A total of 4709 and 9802 differentially expressed genes (DEGs) were identified in MB vs. FB and SS vs. OS, respectively. Genes involved in plant hormone signal and transduction as well as those encoding DNA methyltransferase were found to be differentially expressed between different sex types. Their potential roles in sex determination of G. biloba were discussed. Pistil-related genes were expressed in male buds while anther-specific genes were identified in female buds, suggesting that dioecism in G. biloba was resulted from the selective arrest of reproductive primordia. High correlation of expression level was found between the RNA-Seq and quantitative real-time PCR results. The transcriptome resources that we generated allowed us to characterize gene expression profiles and examine differential expression profiles, which provided foundations for identifying functional genes associated with sex determination in G. biloba. PMID:27379148

Sex Differences in Serotonin 1 Receptor Binding in Rat Brain

NASA Astrophysics Data System (ADS)

Fischette, Christine T.; Biegon, Anat; McEwen, Bruce S.

1983-10-01

Male and female rats exhibit sex differences in binding by serotonin 1 receptors in discrete areas of the brain, some of which have been implicated in the control of ovulation and of gonadotropin release. The sex-specific changes in binding, which occur in response to the same hormonal (estrogenic) stimulus, are due to changes in the number of binding sites. Castration alone also affects the number of binding sites in certain areas. The results lead to the conclusion that peripheral hormones modulate binding by serotonin 1 receptors. The status of the serotonin receptor system may affect the reproductive capacity of an organism and may be related to sex-linked emotional disturbances in humans.

The evolution and consequences of sex-specific reproductive variance.

PubMed

Mullon, Charles; Reuter, Max; Lehmann, Laurent

2014-01-01

Natural selection favors alleles that increase the number of offspring produced by their carriers. But in a world that is inherently uncertain within generations, selection also favors alleles that reduce the variance in the number of offspring produced. If previous studies have established this principle, they have largely ignored fundamental aspects of sexual reproduction and therefore how selection on sex-specific reproductive variance operates. To study the evolution and consequences of sex-specific reproductive variance, we present a population-genetic model of phenotypic evolution in a dioecious population that incorporates previously neglected components of reproductive variance. First, we derive the probability of fixation for mutations that affect male and/or female reproductive phenotypes under sex-specific selection. We find that even in the simplest scenarios, the direction of selection is altered when reproductive variance is taken into account. In particular, previously unaccounted for covariances between the reproductive outputs of different individuals are expected to play a significant role in determining the direction of selection. Then, the probability of fixation is used to develop a stochastic model of joint male and female phenotypic evolution. We find that sex-specific reproductive variance can be responsible for changes in the course of long-term evolution. Finally, the model is applied to an example of parental-care evolution. Overall, our model allows for the evolutionary analysis of social traits in finite and dioecious populations, where interactions can occur within and between sexes under a realistic scenario of reproduction.

The Evolution and Consequences of Sex-Specific Reproductive Variance

PubMed Central

Mullon, Charles; Reuter, Max; Lehmann, Laurent

2014-01-01

Natural selection favors alleles that increase the number of offspring produced by their carriers. But in a world that is inherently uncertain within generations, selection also favors alleles that reduce the variance in the number of offspring produced. If previous studies have established this principle, they have largely ignored fundamental aspects of sexual reproduction and therefore how selection on sex-specific reproductive variance operates. To study the evolution and consequences of sex-specific reproductive variance, we present a population-genetic model of phenotypic evolution in a dioecious population that incorporates previously neglected components of reproductive variance. First, we derive the probability of fixation for mutations that affect male and/or female reproductive phenotypes under sex-specific selection. We find that even in the simplest scenarios, the direction of selection is altered when reproductive variance is taken into account. In particular, previously unaccounted for covariances between the reproductive outputs of different individuals are expected to play a significant role in determining the direction of selection. Then, the probability of fixation is used to develop a stochastic model of joint male and female phenotypic evolution. We find that sex-specific reproductive variance can be responsible for changes in the course of long-term evolution. Finally, the model is applied to an example of parental-care evolution. Overall, our model allows for the evolutionary analysis of social traits in finite and dioecious populations, where interactions can occur within and between sexes under a realistic scenario of reproduction. PMID:24172130

Age- and sex-related characteristics of tonic GABA currents in the rat substantia nigra pars reticulata.

PubMed

Chudomel, O; Hasson, H; Bojar, M; Moshé, S L; Galanopoulou, A S

2015-04-01

Previous studies have shown that the pharmacologic effects of GABAergic drugs and the postsynaptic phasic GABAAergic inhibitory responses in the anterior part of the rat substantia nigra pars reticulata (SNRA) are age- and sex-specific. Here, we investigate whether there are age- and sex-related differences in the expression of the δ GABAA receptor (GABAAR) subunit and GABAAR mediated tonic currents. We have used δ-specific immunochemistry and whole cell patch clamp to study GABAAR mediated tonic currents in the SNRA of male and female postnatal day (PN) PN5-9, PN11-16, and PN25-32 rats. We observed age-related decline, but no sex-specific changes, in bicuculline (BIM) sensitive GABAAR tonic current density, which correlated with the decline in δ subunit in the SNRA between PN15 and 30. Furthermore, we show that the GABAAR tonic currents can be modified by muscimol (GABAAR agonist; partial GABACR agonist), THIP (4,5,6,7-tetrahydroisoxazolo (5,4-c)pyridin-3-ol: α4β3δ GABAARs agonist and GABACR antagonist), and zolpidem (α1-subunit selective GABAAR agonist) in age- and sex-dependent manner specific for each drug. We propose that the emergence of the GABAAR-sensitive anticonvulsant effects of the rat SNRA during development may depend upon the developmental decline in tonic GABAergic inhibition of the activity of rat SNRA neurons, although other sex-specific factors are also involved.

Transgenic over-expression of YY1 induces pathologic cardiac hypertrophy in a sex-specific manner

PubMed Central

Stauffer, Brian L.; Dockstader, Karen; Russell, Gloria; Hijmans, Jamie; Walker, Lisa; Cecil, Mackenzie; Demos-Davies, Kimberly; Medway, Allen; McKinsey, Timothy A.; Sucharov, Carmen C.

2015-01-01

YY1 can activate or repress transcription of various genes. In cardiac myocytes in culture YY1 has been shown to regulate expression of several genes involved in myocyte pathology. YY1 can also acutely protect the heart against detrimental changes in gene expression. In this study we show that cardiac over-expression of YY1 induces pathologic cardiac hypertrophy in male mice, measured by changes in gene expression and lower ejection fraction/fractional shortening. In contrast, female animals are protected against pathologic gene expression changes and cardiac dysfunction. Furthermore, we show that YY1 regulates, in a sex-specific manner, the expression of mammalian enable (Mena), a factor that regulates cytoskeletal actin dynamics and whose expression is increased in several models of cardiac pathology, and that Mena expression in humans with heart failure is sex-dependent. Finally, we show that sex differences in YY1 expression are also observed in human heart failure. In summary, this is the first work to show that YY1 has a sex-specific effect in the regulation of cardiac pathology. PMID:25935483

Sex Differences in Common Sports Injuries.

PubMed

Lin, Cindy; Casey, Ellen; Herman, Daniel; Katz, Nicole; Tenforde, Adam

2018-03-14

Common sports injuries include bone stress injuries (BSIs), anterior cruciate ligament (ACL) injuries, and concussions. Less commonly recognized are the specific sex differences in epidemiology, risk factors, and outcomes of these conditions by sex. An understanding of these factors can improve their clinical management, from prescribing appropriate prehabilitation to guiding postinjury rehabilitation and return to play. This narrative review summarizes the sex differences in the diagnosis and management of BSIs, ACL injuries, and concussions. Although BSIs are more common in female athletes, risk factors for both sexes include prior injury and relative energy deficiency in sport (RED-S). Risk factors in female athletes include smaller calf girth, femoral adduction, and higher rates of loading. Female athletes are also at greater risk for developing ACL injuries in high school and college, but their injury rate is similar in professional sports. Increased lateral tibial slope, smaller ACL size, and suboptimal landing mechanics are additional risk factors more often present in female athletes. Male athletes are more likely to have ACL surgery and have a higher rate of return to sport. Concussions occur more commonly in female athletes; however, female athletes are also more likely to report concussions. Male athletes more commonly sustain concussion through contact with another player. Female athletes more commonly sustain injury from contact with playing equipment. Managing post-concussion symptoms is important, and female athletes may have prolonged symptoms. An understanding of the sex-specific differences in these common sports injuries can help optimize their prehabilitation and rehabilitation. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Sex Mediates the Effects of High-Definition Transcranial Direct Current Stimulation on "Mind-Reading".

PubMed

Martin, A K; Huang, J; Hunold, A; Meinzer, M

2017-12-16

Sex differences in social cognitive ability are well established, including measures of Theory of Mind (ToM). The aim of this study was to investigate if sex mediates the effects of high-definition transcranial direct current stimulation (HD-tDCS) administered to a key hub of the social brain (i.e., the dorsomedial prefrontal cortex, dmPFC) on the Reading the Mind in the Eyes Test (RMET). Forty healthy young adults (18-35 years) were randomly allocated to receive either anodal or cathodal HD-tDCS in sham HD-tDCS controlled, double blind designs. In each of the two sessions, subjects completed the RMET. Anodal stimulation to the dmPFC increased accuracy on the RMET in females only. To assure regional specificity we performed a follow-up study stimulating the right temporoparietal junction and found no effect in either sex. The current study is the first to show improved performance on the RMET after tDCS to the dmPFC in females only. The polarity-specific effects and use of focal HD-tDCS provide evidence for sex-dependent differences in dmPFC function in relation to the RMET. Future studies using tDCS to study or improve ToM, need to consider sex. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

The relationship between muscle action and repetition maximum on the squat and bench press in men and women.

PubMed

Flanagan, Shawn D; Mills, Matthew D; Sterczala, Adam J; Mala, Jesse; Comstock, Brett A; Szivak, Tunde K; DuPont, William H; Looney, David P; McDermott, Danielle M; Hooper, David R; White, Mark T; Dunn-Lewis, Courtenay; Volek, Jeff S; Maresh, Carl M; Kraemer, William J

2014-09-01

The relationship between muscle action and fatigue is not well understood, especially in terms of potential sex-specific differences. The purpose of this investigation was to determine whether a different number of repetitions could be performed on the individual muscle actions of the bench press and squat in men and women. Ten resistance-trained men (n = 10; age, 25.2 ± 1.2 years; height, 178.6 ± 8.8 cm; weight, 91.4 ± 18.1 kg; body fat, 12.7 ± 3.6%) and women (n = 10; age, 25.4 ± 2.4 years; height, 164 ± 4.0 cm; weight, 58.45 ± 3.3 kg; body fat, 20.8 ± 1.5%) participated in this balanced and randomized within-group study. Using 85% of a 1 repetition maximum, over the course of 3 visits, subjects performed 1 eccentric (ECC), concentric (CON), or combined (COMB) set to failure on the squat and bench press. Differences in muscle action and sex-specific number of repetitions to failure were compared on the squat and bench press, where significance was p ≤ 0.05. Across both exercises and sex, we observed significant differences between each of the 3 muscle actions, where the number of repetitions decreased from ECC to COMB to CON. While no sex-specific differences were observed in the squat, women performed significantly more repetitions on the ECC and CON muscle actions of the bench press. Men performed more combined repetitions, however, indicating a greater reliance on the stretch-shortening cycle. Different muscle actions contribute uniquely to the successful performance of a lift and fatigue. These contributions appear to differ in men and women.

Effects of age and sex on developmental neural networks of visual-spatial attention allocation.

PubMed

Rubia, Katya; Hyde, Zoe; Halari, Rozmin; Giampietro, Vincent; Smith, Anna

2010-06-01

Compared to our understanding of the functional maturation of brain networks underlying complex cognitive abilities, hardly anything is known of the neurofunctional development of simpler cognitive abilities such as visuo-spatial attention allocation. Furthermore, nothing is known on the effect of gender on the functional development of attention allocation. This study employed event related functional magnetic resonance imaging to investigate effects of age, sex, and sex by age interactions on the brain activation of 63 males and females, between 13 to 38years, during a visual-spatial oddball task. Behaviourally, with increasing age, speed was traded for accuracy, indicative of a less impulsive performance style in older subjects. Increasing age was associated with progressively increased activation in typical areas of selective attention of lateral fronto-striatal and temporo-parietal brain regions. Sex difference analysis showed enhanced activation in right-hemispheric inferior frontal and superior temporal regions in females, and in left-hemispheric inferior temporo-parietal regions in males. Importantly, the age by sex interaction findings showed that these sex-dimorphic patterns of brain activation may be the result of underlying sex differences in the functional maturation of these brain regions, as females had sex-specific progressive age-correlations in the same right inferior fronto-striato-temporal areas, while male-specific age-correlations were in left medial temporal and parietal areas. The findings demonstrate progressive functional maturation of fronto-striato-parieto-temporal networks of the relatively simple function of attention allocation between early adolescence and mid-adulthood. They furthermore show that sex-dimorphic patterns of enhanced reliance on right inferior frontal, striatal and superior temporal regions in females and of left temporo-parietal regions in males during attention allocation may be the result of underlying sex differences in the functional maturation of these brain regions. Copyright 2010 Elsevier Inc. All rights reserved.

Sex-specific effects of maternal anthropometrics on body composition at birth.

PubMed

O'Tierney-Ginn, Perrie; Presley, Larraine; Minium, Judi; Hauguel deMouzon, Sylvie; Catalano, Patrick M

2014-09-01

The purpose of this study was to assess whether maternal factors that are associated with fetal lean and fat mass differ between sexes. Secondary analysis of a prospective cohort that delivered by scheduled cesarean section from 2004-2013. Maternal blood was collected before surgery for metabolic parameters. Placental weight and neonatal anthropometrics were measured within 48 hours. Anthropometric differences between sexes were assessed with the Student t test. Multiple stepwise regression analysis assessed the relationship between independent maternal variables and neonatal lean body mass (LBM), fat mass (FM), or percentage of fat as dependent variables in male and female infants combined and separately. We analyzed 360 women with normal glucose tolerance and a wide range of pregravid body mass index (16-64 kg/m(2)) and their offspring (male, 194; female, 166). Male infants had more FM (mean difference, 40 ± 18 g; P = .03) and LBM (mean difference, 158 ± 34 g; P < .0001) than female infants. Percentage of body fat and measured maternal variables did not differ between sexes. In both sexes, placental weight had the strongest correlation with both neonatal LBM and FM, which accounted for 20-39% of the variance. In male infants, maternal height, body mass index, and weight gain were significant predictors of both lean and fat mass. In female infants, plasma interleukin-6 and C-reactive protein, respectively, were associated independently with percentage of body fat and LBM. Our findings suggest that the body composition and inflammatory environment of the mother modulate the metabolic fitness of neonates, as predicted by fat and lean mass, in a sex-specific manner. Copyright © 2014 Mosby, Inc. All rights reserved.

Sex-Related Differences in Self-Reported Neurocognitive Impairment among High-Risk Cocaine Users in Methadone Maintenance Treatment Program.

PubMed

Shrestha, Roman; Huedo-Medina, Tania B; Copenhaver, Michael M

2015-01-01

Previous research has suggested possible sex-related differences in executive functioning among cocaine users; however, no studies specifically explain sex-related differences in neurocognitive impairment (NCI) among cocaine users receiving clinical care. Knowledge about this association can aid in the development of targeted prevention strategies to reduce adverse health outcomes. This study was designed to examine the sex-related differences in NCI among high-risk cocaine users receiving substance-abuse treatment. The Neuropsychological Impairment Scale (NIS) was administered to 199 cocaine users (98 men; 101 women), receiving methadone maintainance treatment, to assess self-reported NCI by identifying the patients' awareness of neuropsychological symptoms. We used T-test comparison to find differences in NCI between men and women and multiple regression analysis to explore the relative contribution of sex to NCI. Consistent with prior work, high NCI was evident within this sample, as indicated by high scores on most of the NIS subscales. Women reported greater impairment than men, as evidenced by significantly higher scores on several NIS subscales, after controlling for demographic and other confounding variables. Interestingly, cocaine craving significantly predicted NCI among men but not among women, as suggested by the significant association between cocaine craving and all except one of the NIS subscales. These findings suggest that cocaine users enter into treatment with a range of NCI - with women having significantly more neurocognitive deficits than men - that may contribute to differential treatment outcomes. This highlights the need to include additional services such as neuropsychological screening and sex-specific treatment programs to optimally reduce adverse health outcomes in these high-risk, cognitively impaired patients.

Antidepressant-like effects of guanfacine and sex-specific differences in effects on c-fos immunoreactivity and paired-pulse ratio in male and female mice.

PubMed

Mineur, Yann S; Bentham, Matthew P; Zhou, Wen-Liang; Plantenga, Margreet E; McKee, Sherry A; Picciotto, Marina R

2015-10-01

The a2A-noradrenergic agonist guanfacine can decreases stress-induced smoking in female, but not male, human smokers. It is not known whether these effects are due to effects on mood regulation and/or result from nicotinic-cholinergic interactions. The objective of the study was to determine whether there are sex differences in the effect of guanfacine in tests of anxiolytic and antidepressant efficacy in mice at baseline and in a hypercholinergic model of depression induced by the acetylcholinesterase inhibitor physostigmine. The effects of guanfacine were measured in the light/dark box, tail suspension, and the forced swim test in female and male C57BL/6J mice. In parallel, electrophysiological properties were evaluated in the prefrontal cortex, a critical brain region involved in stress responses. c-fos immunoreactivity was measured in other brain regions known to regulate mood. Despite a baseline sex difference in behavior in the forced swim test (female mice were more immobile), guanfacine had similar, dose-dependent, antidepressant-like effects in mice of both sexes (optimal dose, 0.15 mg/kg). An antidepressant-like effect of guanfacine was also observed following pre-treatment with physostigmine. A sex difference in the paired-pulse ratio in the prefrontal cortex (PFC) (male, 1.4; female, 2.1) was observed at baseline that was normalized by guanfacine. Other brain areas involved in cholinergic control of depression-like behaviors, including the basolateral amygdala and lateral septum, showed sex-specific changes in c-fos expression. Guanfacine has a robust antidepressant-like effect and can reverse a depression-like state induced by increased acetylcholine (ACh) signaling. These data suggest that different brain areas are recruited in female and male mice, despite similar behavioral responses to guanfacine.

Estrogen Actions in the Brain and the Basis for Differential Action in Men and Women: A Case for Sex-Specific Medicines

PubMed Central

McArthur, Simon

2010-01-01

The classic view of estrogen actions in the brain was confined to regulation of ovulation and reproductive behavior in the female of all mamamalian species studied, including humans. Burgeoning evidence now documents profound effects of estrogens on learning, memory, and mood as well as neurodevelopmental and neurodegenerative processes. Most data derive from studies in females, but there is mounting recognition that estrogens play important roles in the male brain, where they can be generated from circulating testosterone by local aromatase enzymes or synthesized de novo by neurons and glia. Estrogen-based therapy therefore holds considerable promise for brain disorders that affect both men and women. However, as investigations are beginning to consider the role of estrogens in the male brain more carefully, it emerges that they have different, even opposite, effects as well as similar effects in male and female brains. This review focuses on these differences, including sex dimorphisms in the ability of estradiol to influence synaptic plasticity, neurotransmission, neurodegeneration, and cognition, which, we argue, are due in a large part to sex differences in the organization of the underlying circuitry. There are notable sex differences in the incidence and manifestations of virtually all central nervous system disorders, including neurodegenerative disease (Parkinson's and Alzheimer's), drug abuse, anxiety, and depression. Understanding the cellular and molecular basis of sex differences in brain physiology and responses to estrogen and estrogen mimics is, therefore, vitally important for understanding the nature and origins of sex-specific pathological conditions and for designing novel hormone-based therapeutic agents that will have optimal effectiveness in men or women. PMID:20392807

Sex differences in olfactory-induced neural activation of the amygdala.

PubMed

Kikusui, Takefumi; Kajita, Mayu; Otsuka, Natsumi; Hattori, Tatsuya; Kumazawa, Kanako; Watarai, Akiyuki; Nagasawa, Miho; Inutsuka, Ayumu; Yamanaka, Akihiro; Matsuo, Naoki; Covington, Herbert E; Mogi, Kazutaka

2018-07-02

Olfactory signals, including the scent of urine, are thought to be processed by specific brain regions, such as the medial amygdala (Me), and regulate sexual behavior in a sex-dependent manner. We aimed to reveal the sex-specific neural circuit from the accessory olfactory bulb (AOB) to Me by using a transgenic mouse. We quantified the long-lasting green fluorescent protein (GFP) expression profile, which was controlled by the c-fos promotor in a sex-dependent manner by the scent of urine. Female urine predominantly activated neurons of the posterodorsal medial amygdala (MePD) in male mice and the posteroventral medial amygdala (MePV) in female mice. Male urine, in contrast, generated the opposite pattern of activation in the Me. Secondary, the selective artificial activation of these circuits was used to examine their specific behavioral function, by using a dual Cre-loxP viral infection. AAV-hSyn-FLEX-hM3Dq-EGFP-the designer receptor exclusively activated by a designer drug-was infused into the AOB after infection with trans-synaptic AAV(DJ)-CMV-mCherry-2A-Cre-TTC into either the MePD or the MePV. Double virus-transfected mice were injected with hM 3 Dq activator and their sexual behavior was monitored. However, selective activation of sex-dependent circuits, i.e., the AOB-MePD or AOB-MePV, did not significantly alter mounting or attack behavior in male mice. There were clear sex differences in the pheromone conveying circuits in the AOB-Me of mice. The sex-dependent functional activation of the Me, however, no effect on behavior. This suggests that a diverse number of nuclei and brain areas are likely to function in concert to successfully facilitate sexual and aggressive behaviors. Copyright © 2017 Elsevier B.V. All rights reserved.

Mad men, women and steroid cocktails: A review of the impact of sex and other factors on anabolic androgenic steroids effects on affective behaviors

PubMed Central

Henderson, Leslie P.

2016-01-01

Rationale For several decades, elite athletes and a growing number of recreational consumers have used anabolic androgenic steroids (AAS) as performance enhancing drugs. Despite mounting evidence that illicit use of these synthetic steroids has detrimental effects on affective states, information available on sex-specific actions of these drugs is lacking. Objectives The focus of this review is to assess information to date on the importance of sex and its interaction with other environmental factors on affective behaviors, with an emphasis on data derived from non-human studies. Methods The PubMed database was searched for relevant studies in both sexes. Results Studies examining AAS use in females are limited, reflecting the lower prevalence of use in this sex. Data, however, indicate significant sex-specific differences in AAS effects on anxiety-like and aggressive behaviors, interactions with other drugs of abuse, and the interplay of AAS with other environmental factors such as diet and exercise. Conclusions Current methods for assessing AAS use have limitations that suggest biases of both under- and over-reporting, which may be amplified for females who are poorly represented in self-report studies of human subjects and are rarely used in animal studies. Data from animal literature suggest that there are significant sex-specific differences in the impact of AAS on aggression, anxiety, and concomitant use of other abused substances. These results have relevance for human females who take these drugs as performance enhancing substances and for transgender XX individuals who may illicitly self-administer AAS as they transition to a male gender identity. PMID:26758282

High-resolution melting analysis for bird sexing: a successful approach to molecular sex identification using different biological samples.

PubMed

Morinha, Francisco; Travassos, Paulo; Seixas, Fernanda; Santos, Nuno; Sargo, Roberto; Sousa, Luís; Magalhães, Paula; Cabral, João A; Bastos, Estela

2013-05-01

High-resolution melting (HRM) analysis is a very attractive and flexible advanced post-PCR method with high sensitivity/specificity for simple, fast and cost-effective genotyping based on the detection of specific melting profiles of PCR products. Next generation real-time PCR systems, along with improved saturating DNA-binding dyes, enable the direct acquisition of HRM data after quantitative PCR. Melting behaviour is particularly influenced by the length, nucleotide sequence and GC content of the amplicons. This method is expanding rapidly in several research areas such as human genetics, reproductive biology, microbiology and ecology/conservation of wild populations. Here we have developed a successful HRM protocol for avian sex identification based on the amplification of sex-specific CHD1 fragments. The melting curve patterns allowed efficient sexual differentiation of 111 samples analysed (plucked feathers, muscle tissues, blood and oral cavity epithelial cells) of 14 bird species. In addition, we sequenced the amplified regions of the CHD1 gene and demonstrated the usefulness of this strategy for the genotype discrimination of various amplicons (CHD1Z and CHD1W), which have small size differences, ranging from 2 bp to 44 bp. The established methodology clearly revealed the advantages (e.g. closed-tube system, high sensitivity and rapidity) of a simple HRM assay for accurate sex differentiation of the species under study. The requirements, strengths and limitations of the method are addressed to provide a simple guide for its application in the field of molecular sexing of birds. The high sensitivity and resolution relative to previous real-time PCR methods makes HRM analysis an excellent approach for improving advanced molecular methods for bird sexing. © 2013 Blackwell Publishing Ltd.

Startling Differences: Using the Acoustic Startle Response to Study Sex Differences and Neurosteroids in Affective Disorders.

PubMed

Hantsoo, Liisa; Golden, Carla E M; Kornfield, Sara; Grillon, Christian; Epperson, C Neill

2018-05-18

Neuroactive steroid hormones, such as estradiol and progesterone, likely play a role in the pathophysiology of female-specific psychiatric disorders such as premenstrual dysphoric disorder (PMDD) and postpartum depression and may contribute to the marked sex differences observed in the incidence and presentation of affective disorders. However, few tools are available to study the precise contributions of these neuroactive steroids (NSs). In this review, we propose that the acoustic startle response (ASR), an objective measure of an organism's response to an emotional context or stressor, is sensitive to NSs. As such, the ASR represents a unique translational tool that may help to elucidate the contribution of NSs to sex differences in psychiatric disorders. Findings suggest that anxiety-potentiated startle (APS) and prepulse inhibition of startle (PPI) are the most robust ASR paradigms for assessing contribution of NSs to affective disorders, while affective startle response modulation (ASRM) appears less diagnostic of sex or menstrual cycle (MC) effects. However, few studies have appropriately used ASR to test a priori hypotheses about sex or MC differences. We recommend that ASR studies account for sex as a biological variable (SABV) and hormonal status to further knowledge of NS contribution to affective disorders.

Different inhibitory potential of sex hormones on NNK detoxification in vitro: A possible explanation for gender-specific lung cancer risk.

PubMed

Stapelfeld, Claudia; Neumann, Karolina-Theresa; Maser, Edmund

2017-10-01

Smoking women are probably at a higher risk to develop lung cancer than men. Different explanations exist for these findings, a gender-specific impairment of tobacco carcinogen metabolism being one of them. In this study, we examined the inhibition of NNK reduction to NNAL, the first and most important detoxication step of this tobacco-specific carcinogen. It is mediated by different carbonyl reductases of the SDR (CBR1 and 11βHSD1) and AKR (AKR1B10, AKR1C1, AKR1C2 and AKR1C4) superfamilies. Inhibition constants of NNK reduction were determined with male (testosterone) and female (estradiol, progesterone) sex hormones and the contraceptives ethinylestradiol and drospirenone in A549 cells and with purified enzymes. Female sex hormones turned out to be stronger inhibitors than testosterone. The gestagen progesterone and its synthetic derivative drospirenone are the strongest inhibitors with K i -values similar to hormone levels in pregnant women or women using hormonal contraceptives. Therefore, pregnancy or hormonal contraception may commit these women as high risk groups. The results of this study support the hypothesis that women bear a higher lung cancer risk when smoking because of female sex hormones acting as inhibitors of NNK detoxication. Copyright © 2017 Elsevier B.V. All rights reserved.

Neuropsychological sex differences associated with age of initiated use among young adult cannabis users.

PubMed

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

2015-01-01

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

Sex-biased chromatin and regulatory cross-talk between sex chromosomes, autosomes, and mitochondria

PubMed Central

2014-01-01

Several autoimmune and neurological diseases exhibit a sex bias, but discerning the causes and mechanisms of these biases has been challenging. Sex differences begin to manifest themselves in early embryonic development, and gonadal differentiation further bifurcates the male and female phenotypes. Even at this early stage, however, there is evidence that males and females respond to environmental stimuli differently, and the divergent phenotypic responses may have consequences later in life. The effect of prenatal nutrient restriction illustrates this point, as adult women exposed to prenatal restrictions exhibited increased risk factors of cardiovascular disease, while men exposed to the same condition did not. Recent research has examined the roles of sex-specific genes, hormones, chromosomes, and the interactions among them in mediating sex-biased phenotypes. Such research has identified testosterone, for example, as a possible protective agent against autoimmune disorders and an XX chromosome complement as a susceptibility factor in murine models of lupus and multiple sclerosis. Sex-biased chromatin is an additional and likely important component. Research suggesting a role for X and Y chromosome heterochromatin in regulating epigenetic states of autosomes has highlighted unorthodox mechanisms of gene regulation. The crosstalk between the Y chromosomes and autosomes may be further mediated by the mitochondria. The organelles have solely maternal transmission and exert differential effects on males and females. Altogether, research supports the notion that the interaction between sex-biased elements might exert novel regulatory functions in the genome and contribute to sex-specific susceptibilities to autoimmune and neurological diseases. PMID:24422881

[Sex- and gender-sensitive research in epidemiology and medicine: how can this be achieved? Aims and first results of the network "Sex-/Gender-Sensitive Research in Epidemiology, Neurosciences and Genetics/Cancer Research"].

PubMed

Jahn, I; Gansefort, D; Kindler-Röhrborn, A; Pfleiderer, B

2014-09-01

It is considered general knowledge among physicians and epidemiologists that biological and social aspects associated with being male or female have a strong influence on health and disease. Integrating these aspects into research is necessary to counteract the problems--including ethical problems--resulting from a different evidence basis for men and women. From January 2011 to June 2014 the Federal Ministry of Education and Research supported the network "Sex-/Gender-Sensitive Research in Epidemiology, Neuroscience and Genetics/Cancer Research" with three subprojects, which aimed to promote gender-sensitive research practices. The concepts and results are presented in this article. The subproject gathered data (literature analyses, questionnaires) and offered programs for young scientists. Experiences and results were collected and generalized, for instance, in the form of definitions of terms. 50 young scientists have taken part in the training program, identifying associations and barriers in sex-/gender-sensitive research. Among others, a working definition for "sex-/gender-sensitive research" was developed, as well as definitions for the terms "sex-specific" (for biological characteristics that are specific to men or women) and "sex-/gender-dependent" or "sex-/gender-associated" (for biological and social factors, for which the extent of occurrence differs between the sexes). The concepts realized by the network are well suited to stimulate further development and discussions. The definition of terms is an important base for a productive and high-yielding interdisciplinary collaboration.

Sex-specific substance abuse treatment for female healthcare professionals: implications.

PubMed

Koos, Erin; Brand, Michael; Rojas, Julio; Li, Ji

2014-01-01

Gender plays a significant role in the development and treatment of substance abuse disorders. Sex-specific treatment for girls and women has recurrently proven more effective, with better outcomes than traditional treatment. Research on impaired healthcare professionals (HCPs) has largely focused on men, garnering little attention for women and sex differences. With the increasing numbers of female HCPs, it is imperative to identify potential sex differences that may have implications for treatment. Our study compared a convenience sample of male and female HCPs with substance abuse disorders treated in an outpatient program to identify sex differences that may have implications for treatment. Our sample consisted of 96 HCPs (54 men, 42 women) and 17 non-healthcare professional (N-HCP) women. All of the participants were evaluated using the program's clinical interview and the Personality Assessment Inventory (PAI). Chart review data contained categorical variables, qualitative variables, diagnoses, and psychological test scores. A second analysis was conducted through two separate comparisons: the PAI results of comparing impaired female HCPs with impaired male HCPs and the PAI results of comparing impaired female HCPs with impaired female N-HCPs. Statistically significant differences indicated more male participants received prior treatment and more intensive treatment than female participants. More female subjects reported being diagnosed as having a comorbid psychiatric condition and taking psychotropic medications. Several statistically significant differences in the PAI scores were found. Among female HCPs, elevations were found in anxiety, depression, paranoia, and borderline personality disorder. Substantive differences, although not statistically significant, were elevations in somatic complaints and anxiety disorders in female HCPs. In the comparison of female HCPs and N-HCPs, the only statistically significant difference was the significantly higher anxiety score of N-HCPs. The results indicate greater differences between female HCPs and male HCPs than between female HCPs and N-HCPs.

Relations between the characteristics and psychological comorbidities of chronic pruritus differ between men and women: women are more anxious than men.

PubMed

Stumpf, A; Ständer, S; Warlich, B; Fritz, F; Bruland, P; Pfleiderer, B; Heuft, G; Schneider, G

2015-01-01

Although sex and gender are becoming more important in diagnostics and therapy, there is still little knowledge about sex-specific differences in chronic pruritus (CP). To compare, taking into consideration the characteristics of pruritus, sex-specific differences in psychological symptoms in patients with CP. Sociodemographic data, data on the clinical characteristics of the skin and CP were documented over a 1-year period in all patients attending the Competence Center Chronic Pruritus of the University Hospital Münster for the first time. All patients completed the Hospital Anxiety and Depression Scale. Student's t-tests for independent study groups and linear regression analyses were applied. A total of 619 patients (278 men, 341 women) were included in the analysis. Women were more anxious than men, but were not more depressed. A linear regression analysis indicated that depression and anxiety scores in women were related to the average intensity of pruritus during the previous 4 weeks and to a more generalized pruritus at the beginning of CP; older age in women also correlated with the scores on the depression subscale. Interestingly, the associations were different in men: scores on the depression scale were associated with the diagnosis of CP pruritus with multiple scratch lesions. There are sex-specific differences in the relationship between the psychological symptoms and clinical characteristics of CP; higher anxiety scores were achieved by women. Whether psychological symptoms can be reversed when CP and scratch lesions improve is an issue that needs further exploration. © 2014 British Association of Dermatologists.

Gender-Specific Gene Expression in Post-Mortem Human Brain: Localization to Sex Chromosomes

PubMed Central

Vawter, Marquis P; Evans, Simon; Choudary, Prabhakara; Tomita, Hiroaki; Meador-Woodruff, Jim; Molnar, Margherita; Li, Jun; Lopez, Juan F; Myers, Rick; Cox, David; Watson, Stanley J; Akil, Huda; Jones, Edward G; Bunney, William E

2011-01-01

Gender differences in brain development and in the prevalence of neuropsychiatric disorders such as depression have been reported. Gender differences in human brain might be related to patterns of gene expression. Microarray technology is one useful method for investigation of gene expression in brain. We investigated gene expression, cell types, and regional expression patterns of differentially expressed sex chromosome genes in brain. We profiled gene expression in male and female dorsolateral prefrontal cortex, anterior cingulate cortex, and cerebellum using the Affymetrix oligonucleotide microarray platform. Differentially expressed genes between males and females on the Y chromosome (DBY, SMCY, UTY, RPS4Y, and USP9Y) and X chromosome (XIST) were confirmed using real-time PCR measurements. In situ hybridization confirmed the differential expression of gender-specific genes and neuronal expression of XIST, RPS4Y, SMCY, and UTY in three brain regions examined. The XIST gene, which silences gene expression on regions of the X chromosome, is expressed in a subset of neurons. Since a subset of neurons express gender-specific genes, neural subpopulations may exhibit a subtle sexual dimorphism at the level of differences in gene regulation and function. The distinctive pattern of neuronal expression of XIST, RPS4Y, SMCY, and UTY and other sex chromosome genes in neuronal subpopulations may possibly contribute to gender differences in prevalence noted for some neuropsychiatric disorders. Studies of the protein expression of these sex- chromosome-linked genes in brain tissue are required to address the functional consequences of the observed gene expression differences. PMID:14583743

Sex- and Age-Dependence of Region- and Layer-Specific Knee Cartilage Composition (Spin-Spin-Relaxation Time) in Healthy Reference Subjects

PubMed Central

Wirth, Wolfgang; Maschek, Susanne; Eckstein, Felix

2016-01-01

SUMMARY Compositional measures of articular cartilage are accessible in vivo by magnetic resonance imaging (MRI) based relaxometry and cartilage spin-spin transverse relaxation time (T2) has been related to tissue hydration, collagen content and orientation, and mechanical (functional) properties of articular cartilage. The objective of the current study was therefore to evaluate subregional variation, and sex- and age-differences, in laminar (deep and superficial) femorotibial cartilage T2 relaxation time in healthy adults. To this end, we studied the right knees of 92 healthy subjects from the Osteoarthritis Initiative reference cohort (55 women, 37 men; age range 45–78 years; BMI 24.4±3.1) without knee pain, radiographic signs, or risk factors of knee osteoarthritis in either knee. T2 of the deep and superficial femorotibial cartilages was determined in 16 femorotibial subregions, using a multi-echo spin-echo (MESE) MRI sequence. Significant subregional variation in femorotibial cartilage T2 was observed for the superficial and for the deep (both p<0.001) cartilage layer (Friedman test). Yet, layer- and region-specific femorotibial T2 did not differ between men and women, or between healthy adults below and above the median age (54y). In conclusion, this first study to report subregional (layer-specific) compositional variation of femorotibial cartilage T2 in healthy adults identifies significant differences in both superficial and deep cartilage T2 between femorotibial subregions. However, no relevant sex- or age-dependence of cartilage T2 was observed between age 45–78y. The findings suggest that a common, non-sex-specific set of layer-and region-specific T2 reference values can be used to identify compositional pathology in joint disease for this age group. PMID:27836800

Children's Recall and Recognition of Sex Role Stereotyped and Discrepant Information.

ERIC Educational Resources Information Center

Trepanier-Street, Mary L.; Kropp, Jerri Jaudon

Two studies were conducted to investigate the influence of differing levels of sex role stereotyped and discrepant information on the immediate and delayed memory of young children. Specifically, kindergarten and 2nd-grade children's recall and recognition of stereotyped, moderately discrepant, and highly discrepant pictures were compared. In…

Replication asynchrony and differential condensation of X chromosomes in female platypus (Ornithorhynchus anatinus).

PubMed

Ho, Kristen K K; Deakin, Janine E; Wright, Megan L; Graves, Jennifer A Marshall; Grützner, Frank

2009-01-01

A common theme in the evolution of sex chromosomes is the massive loss of genes on the sex-specific chromosome (Y or W), leading to a gene imbalance between males (XY) and females (XX) in a male heterogametic species, or between ZZ and ZW in a female heterogametic species. Different mechanisms have evolved to compensate for this difference in dosage of X-borne genes between sexes. In therian mammals, one of the X chromosomes is inactivated, whereas bird dosage compensation is partial and gene-specific. In therian mammals, hallmarks of the inactive X are monoallelic gene expression, late DNA replication and chromatin condensation. Platypuses have five pairs of X chromosomes in females and five X and five Y chromosomes in males. Gene expression analysis suggests a more bird-like partial and gene-specific dosage compensation mechanism. We investigated replication timing and chromosome condensation of three of the five X chromosomes in female platypus. Our data suggest asynchronous replication of X-specific regions on X(1), X(3) and X(5) but show significantly different condensation between homologues for X(3) only, and not for X(1) or X(5). We discuss these results in relation to recent gene expression analysis of X-linked genes, which together give us insights into possible mechanisms of dosage compensation in platypus.

Sex differences in the clinical characteristics and brain gray matter volume alterations in unmedicated patients with major depressive disorder.

PubMed

Yang, Xiao; Peng, Zugui; Ma, Xiaojuan; Meng, Yajing; Li, Mingli; Zhang, Jian; Song, Xiuliu; Liu, Ye; Fan, Huanhuan; Zhao, Liansheng; Deng, Wei; Li, Tao; Ma, Xiaohong

2017-05-30

This study was to explore the sex differences in clinical characteristics and brain gray matter volume (GMV) alterations in 29 male patients with major depressive disorder (MDDm), 53 female patients with MDD (MDDf), and in 29 male and 53 female matched healthy controls. Maps of GMV were constructed using magnetic resonance imaging data and compared between groups. We evaluated clinical symptoms using the Hamilton Rating Scale for Depression and obtained a total score and five syndrome scores. A two-factor ANCOVA model was specified using SPM8, with sex and diagnosis as the between-subject factors. We found that: (1) significant GMV increase in the left cerebellum and GMV reduction in the bilateral middle temporal gyrus and left ventral medial prefrontal gyrus occurred selectively in male patients, while the GMV reduction in the left lingual gyrus and dorsal medial prefrontal gyrus occurred selectively in female patients; (2) MDDf may have experienced more severe sleep disturbance than MDDm; and (3) the severity of sleep symptom could be predicted by the sex specific brain structural alterations in depressions. These findings suggest that sex specific anatomical alterations existed in MDD, and these alterations were associated with the clinical symptoms.

Analysis of sex-specific injury patterns and risk factors in young high-level athletes.

PubMed

Frisch, A; Seil, R; Urhausen, A; Croisier, J L; Lair, M L; Theisen, D

2009-12-01

This study analyzed sex-specific injury patterns and risk factors in young athletes (n=256) from 12 sport disciplines practicing at the national or the international level in the Grand-Duchy of Luxembourg. Injury occurrence as a result of sport practice was analyzed retrospectively over the year 2006 using a standardized self-administered questionnaire. Overall incidence was not different between girls and boys (1.20 and 1.21 injuries/1000 athlete-hours, respectively), but in the context of team sport competition girls tended to be at a greater risk (rate ratio 2.05, P=0.053). Girls had a higher proportion of injuries in the ankle/foot region compared with boys (34.8% vs 16.8%). No sex-related differences were found regarding injury severity. Multivariate logistic regression (controlling for age and practice volume) revealed that girls' team sports were associated with a greater injury risk compared with individual sports [odds ratio (OR) of 4.76], while in boys this was observed for racket sports (OR=3.31). Furthermore, physical or emotional stress tended to be a specific risk factor in girls. There was a tendency for injury outside sports to be coupled to a higher injury risk in girls and boys. Consideration of sex-specific injury patterns and risk factors could be of importance for effective injury prevention.

Inflammatory and mitochondrial gene expression data in GPER-deficient cardiomyocytes from male and female mice.

PubMed

Wang, Hao; Sun, Xuming; Chou, Jeff; Lin, Marina; Ferrario, Carlos M; Zapata-Sudo, Gisele; Groban, Leanne

2017-02-01

We previously showed that cardiomyocyte-specific G protein-coupled estrogen receptor (GPER) gene deletion leads to sex-specific adverse effects on cardiac structure and function; alterations which may be due to distinct differences in mitochondrial and inflammatory processes between sexes. Here, we provide the results of Gene Set Enrichment Analysis (GSEA) based on the DNA microarray data from GPER-knockout versus GPER-intact (intact) cardiomyocytes. This article contains complete data on the mitochondrial and inflammatory response-related gene expression changes that were significant in GPER knockout versus intact cardiomyocytes from adult male and female mice. The data are supplemental to our original research article "Cardiomyocyte-specific deletion of the G protein-coupled estrogen receptor (GPER) leads to left ventricular dysfunction and adverse remodeling: a sex-specific gene profiling" (Wang et al., 2016) [1]. Data have been deposited to the Gene Expression Omnibus (GEO) database repository with the dataset identifier GSE86843.

Sex differences in the neural circuit that mediates female sexual receptivity

PubMed Central

Flanagan-Cato, Loretta M.

2011-01-01

Female sexual behavior in rodents, typified by the lordosis posture, is hormone-dependent and sex-specific. Ovarian hormones control this behavior via receptors in the hypothalamic ventromedial nucleus (VMH). This review considers the sex differences in the morphology, neurochemistry and neural circuitry of the VMH to gain insights into the mechanisms that control lordosis. The VMH is larger in males compared with females, due to more synaptic connections. Another sex difference is the responsiveness to estradiol, with males exhibiting muted, and in some cases reverse, effects compared with females. The lack of lordosis in males may be explained by differences in synaptic organization or estrogen responsiveness, or both, in the VMH. However, given that damage to other brain regions unmasks lordosis behavior in males, a male-typical VMH is unlikely the main factor that prevents lordosis. In females, key questions remain regarding the mechanisms whereby ovarian hormones modulate VMH function to promote lordosis. PMID:21338620

XX/XY Sex Chromosomes in the South American Dwarf Gecko (Gonatodes humeralis).

PubMed

Gamble, Tony; McKenna, Erin; Meyer, Wyatt; Nielsen, Stuart V; Pinto, Brendan J; Scantlebury, Daniel P; Higham, Timothy E

2018-05-11

Sex-specific genetic markers identified using restriction site-associated DNA sequencing, or RADseq, permits the recognition of a species' sex chromosome system in cases where standard cytogenetic methods fail. Thus, species with male-specific RAD markers have an XX/XY sex chromosome system (male heterogamety) while species with female-specific RAD markers have a ZZ/ZW sex chromosome (female heterogamety). Here, we use RADseq data from 5 male and 5 female South American dwarf geckos (Gonatodes humeralis) to identify an XX/XY sex chromosome system. This is the first confidently known sex chromosome system in a Gonatodes species. We used a low-coverage de novo G. humeralis genome assembly to design PCR primers to validate the male-specificity of a subset of the sex-specific RADseq markers and describe how even modest genome assemblies can facilitate the design of sex-specific PCR primers in species with diverse sex chromosome systems.

Anatomically Discrete Sex Differences in Neuroplasticity in Zebra Finches as Reflected by Perineuronal Nets

PubMed Central

Cornez, Gilles; ter Haar, Sita M.; Cornil, Charlotte A.; Balthazart, Jacques

2015-01-01

Large morphological sex differences in the vertebrate brain were initially identified in song control nuclei of oscines. Besides gross differences between volumes of nuclei in males and females, sex differences also concern the size and dendritic arborization of neurons and various neurochemical markers, such as the calcium-binding protein parvalbumin (PV). Perineuronal nets (PNN) of the extracellular matrix are aggregates of different compounds, mainly chondroitin sulfate proteoglycans, that surround subsets of neurons, often expressing PV. PNN develop in zebra finches song control nuclei around the end of the sensitive period for song learning and tutor deprivation, known to delay the end of the song learning sensitive period, decreases the numbers of PNN in HVC. We demonstrate here the existence in zebra finches of a major sex difference (males > females) affecting the number of PNN (especially those surrounding PV-positive cells) in HVC and to a smaller extent the robust nucleus of the arcopallium, RA, the two main nuclei controlling song production. These differences were not present in Area X and LMAN, the lateral magnocellular nucleus of the anterior nidopallium. A dense expression of material immunoreactive for chondroitin sulfate was also detected in several nuclei of the auditory and visual pathways. This material was often organized in perineuronal rings but quantification of these PNN did not reveal any sex difference with the exception that the percentage of PNN surrounding PV-ir cells in the dorsal lateral mesencephalic nucleus, MLd, was larger in females than in males, a sex difference in the opposite direction compared to what is seen in HVC and RA. These data confirm and extend previous studies demonstrating the sex difference affecting PNN in HVC-RA by showing that this sex difference is anatomically specific and does not concern visual or auditory pathways. PMID:25848776

Sex differences in neural activation following different routes of oxytocin administration in awake adult rats.

PubMed

Dumais, Kelly M; Kulkarni, Praveen P; Ferris, Craig F; Veenema, Alexa H

2017-07-01

The neuropeptide oxytocin (OT) regulates social behavior in sex-specific ways across species. OT has promising effects on alleviating social deficits in sex-biased neuropsychiatric disorders. However little is known about potential sexually dimorphic effects of OT on brain function. Using the rat as a model organism, we determined whether OT administered centrally or peripherally induces sex differences in brain activation. Functional magnetic resonance imaging was used to examine blood oxygen level-dependent (BOLD) signal intensity changes in the brains of awake rats during the 20min following intracerebroventricular (ICV; 1μg/5μl) or intraperitoneal (IP; 0.1mg/kg) OT administration as compared to baseline. ICV OT induced sex differences in BOLD activation in 26 out of 172 brain regions analyzed, with 20 regions showing a greater volume of activation in males (most notably the nucleus accumbens and insular cortex), and 6 regions showing a greater volume of activation in females (including the lateral and central amygdala). IP OT also elicited sex differences in BOLD activation with a greater volume of activation in males, but this activation was found in different and fewer (10) brain regions compared to ICV OT. In conclusion, exogenous OT modulates neural activation differently in male versus female rats with the pattern and magnitude, but not the direction, of sex differences depending on the route of administration. These findings highlight the need to include both sexes in basic and clinical studies to fully understand the role of OT on brain function. Copyright © 2017 Elsevier Ltd. All rights reserved.

Identification of the sex genes in an early diverged fungus.

PubMed

Idnurm, Alexander; Walton, Felicia J; Floyd, Anna; Heitman, Joseph

2008-01-10

Sex determination in fungi is controlled by a small, specialized region of the genome in contrast to the large sex-specific chromosomes of animals and some plants. Different gene combinations reside at these mating-type (MAT) loci and confer sexual identity; invariably they encode homeodomain, alpha-box, or high mobility group (HMG)-domain transcription factors. So far, MAT loci have been characterized from a single monophyletic clade of fungi, the Dikarya (the ascomycetes and basidiomycetes), and the ancestral state and evolutionary history of these loci have remained a mystery. Mating in the basal members of the kingdom has been less well studied, and even their precise taxonomic inter-relationships are still obscure. Here we apply bioinformatic and genetic mapping to identify the sex-determining (sex) region in Phycomyces blakesleeanus (Zygomycota), which represents an early branch within the fungi. Each sex allele contains a single gene that encodes an HMG-domain protein, implicating the HMG-domain proteins as an earlier form of fungal MAT loci. Additionally, one allele also contains a copy of a unique, chromosome-specific repetitive element, suggesting a generalized mechanism for the earliest steps in the evolution of sex determination and sex chromosome structure in eukaryotes.

Sex Differences in Obesity and Mental Health.

PubMed

Tronieri, Jena Shaw; Wurst, Courtney McCuen; Pearl, Rebecca L; Allison, Kelly C

2017-06-01

The purposes of this study were to examine the relationships between obesity and a wide range of mental health issues and to identify where sex differences exist and may vary across disorders. Research on sex differences in the relationship between obesity and psychiatric disorders is more abundant in some areas, such as depression and eating disorders, than others, such as anxiety, trauma, and substance use. However, for most of the disorders, their relationships with obesity and sex are complex and are usually moderated by additional variables. Thus, studies that find stronger relationships for women between depression and obesity cross-sectionally do not tell the whole story, as longitudinal studies suggest that this relationship may also be present among men, particularly when confounders are considered. For those with eating disorders, men and women with obesity are fairly equally affected, and weight and shape concerns may play a role in maintaining these behaviors for both sexes. Weight stigma, though, seems to have worse consequences for women than men with obesity. Sex differences exist in relation to the associations between mental health and obesity. However, these differences vary by disorder, with disorder-specific moderators playing a role, such as age for depressive disorders, comorbid depression for anxiety disorders, and weight and shape concerns for eating disorders. More work is needed to understand if sex differences play a role in the relationship between obesity and anxiety, trauma, and substance use disorders.

Examining sex differences in DSM-IV-TR narcissistic personality disorder symptom expression using Item Response Theory (IRT).

PubMed

Hoertel, Nicolas; Peyre, Hugo; Lavaud, Pierre; Blanco, Carlos; Guerin-Langlois, Christophe; René, Margaux; Schuster, Jean-Pierre; Lemogne, Cédric; Delorme, Richard; Limosin, Frédéric

2017-12-14

The limited published literature on the subject suggests that there may be differences in how females and males experience narcissistic personality disorder (NPD) symptoms. The aim of this study was to use methods based on item response theory to examine whether, when equating for levels of NPD symptom severity, there are sex differences in the likelihood of reporting DSM-IV-TR NPD symptoms. We conducted these analyses using a large, nationally representative sample from the USA (n=34,653), the second wave of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). There were statistically and clinically significant sex differences for 2 out of the 9 DSM-IV-TR NPD symptoms. We found that males were more likely to endorse the item 'lack of empathy' at lower levels of narcissistic personality disorder severity than females. The item 'being envious' was a better indicator of NPD severity in males than in females. There were no clinically significant sex differences on the remaining NPD symptoms. Overall, our findings indicate substantial sex differences in narcissistic personality disorder symptom expression. Although our results may reflect sex-bias in diagnostic criteria, they are consistent with recent views suggesting that narcissistic personality disorder may be underpinned by shared and sex-specific mechanisms. Copyright © 2017 Elsevier B.V. All rights reserved.

The clinician perspective on sex differences in autism spectrum disorders.

PubMed

Jamison, Rene; Bishop, Somer L; Huerta, Marisela; Halladay, Alycia K

2017-08-01

Research studies using existing samples of individuals with autism spectrum disorders have identified differences in symptoms between males and females. Differences are typically reported in school age and adolescence, with similarities in symptom presentation at earlier ages. However, existing studies on sex differences are significantly limited, making it challenging to discern if, how, and at what point in development females with autism spectrum disorder actually exhibit a different behavioral presentation than males. The purpose of this study was to gather impressions from a large group of clinicians to isolate specific areas for future study of sex differences. Clinicians were surveyed about their opinions and perceptions of symptom severity in females, as compared to males, at different points during development. They were also asked to provide open-ended responses about female symptom presentation. Consistent with previous literature, clinicians noted more sex-related differences in restricted and repetitive behaviors and fewer differences for social communication features. Differences were most commonly observed in school age and adolescence, suggesting this time period as a critical and particularly vulnerable window for females with autism spectrum disorder. The results are discussed in the context of other male/female differences across development so that more targeted investigations of autism spectrum disorder sex differences across development.

The aquaglyceroporin AQP9 contributes to the sex-specific effects of in utero arsenic exposure on placental gene expression.

PubMed

Winterbottom, Emily F; Koestler, Devin C; Fei, Dennis Liang; Wika, Eric; Capobianco, Anthony J; Marsit, Carmen J; Karagas, Margaret R; Robbins, David J

2017-06-14

Sex-specific factors play a major role in human health and disease, including responses to environmental stresses such as toxicant exposure. Increasing evidence suggests that such sex differences also exist during fetal development. In a previous report using the resources of the New Hampshire Birth Cohort Study (NHBCS), we found that low-to-moderate in utero exposure to arsenic, a highly toxic and widespread pollutant, was associated with altered expression of several key developmental genes in the fetal portion of the placenta. These associations were sex-dependent, suggesting that in utero arsenic exposure differentially impacts male and female fetuses. In the present study, we investigated the molecular basis for these sex-specific responses to arsenic. Using NanoString technology, we further analyzed the fetal placenta samples from the NHBCS for the expression of genes encoding arsenic transporters and metabolic enzymes. Multivariable linear regression analysis was used to examine their relationship with arsenic exposure and with key developmental genes, after stratification by fetal sex. We found that maternal arsenic exposure was strongly associated with expression of the AQP9 gene, encoding an aquaglyceroporin transporter, in female but not male fetal placenta. Moreover, AQP9 expression associated with that of a subset of female-specific arsenic-responsive genes. Our results suggest that AQP9 is upregulated in response to arsenic exposure in female, but not male, fetal placenta. Based on these results and prior studies, increased AQP9 expression may lead to increased arsenic transport in the female fetal placenta, which in turn may alter the expression patterns of key developmental genes that we have previously shown to be associated with arsenic exposure. Thus, this study suggests that AQP9 may play a role in the sex-specific effects of in utero arsenic exposure.

Geographical and Temporal Body Size Variation in a Reptile: Roles of Sex, Ecology, Phylogeny and Ecology Structured in Phylogeny

PubMed Central

Aragón, Pedro; Fitze, Patrick S.

2014-01-01

Geographical body size variation has long interested evolutionary biologists, and a range of mechanisms have been proposed to explain the observed patterns. It is considered to be more puzzling in ectotherms than in endotherms, and integrative approaches are necessary for testing non-exclusive alternative mechanisms. Using lacertid lizards as a model, we adopted an integrative approach, testing different hypotheses for both sexes while incorporating temporal, spatial, and phylogenetic autocorrelation at the individual level. We used data on the Spanish Sand Racer species group from a field survey to disentangle different sources of body size variation through environmental and individual genetic data, while accounting for temporal and spatial autocorrelation. A variation partitioning method was applied to separate independent and shared components of ecology and phylogeny, and estimated their significance. Then, we fed-back our models by controlling for relevant independent components. The pattern was consistent with the geographical Bergmann's cline and the experimental temperature-size rule: adults were larger at lower temperatures (and/or higher elevations). This result was confirmed with additional multi-year independent data-set derived from the literature. Variation partitioning showed no sex differences in phylogenetic inertia but showed sex differences in the independent component of ecology; primarily due to growth differences. Interestingly, only after controlling for independent components did primary productivity also emerge as an important predictor explaining size variation in both sexes. This study highlights the importance of integrating individual-based genetic information, relevant ecological parameters, and temporal and spatial autocorrelation in sex-specific models to detect potentially important hidden effects. Our individual-based approach devoted to extract and control for independent components was useful to reveal hidden effects linked with alternative non-exclusive hypothesis, such as those of primary productivity. Also, including measurement date allowed disentangling and controlling for short-term temporal autocorrelation reflecting sex-specific growth plasticity. PMID:25090025