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Sample records for sex specific effects

  1. Sex-specific maternal effects in a viviparous fish

    PubMed Central

    Kruuk, Loeske E. B.; Livingston, Julianne; Kahn, Andrew; Jennions, Michael D.

    2015-01-01

    Mothers vary in their effects on their offspring, but studies of variation in maternal effects rarely ask whether differences between mothers are consistent for sons and daughters. Here, we analysed maternal effects in the mosquitofish Gambusia holbrooki for development time and adult size of sons and daughters, and a primary male sexual character (gonopodium length). We found substantial maternal effects on all traits, most notably for gonopodium length. There were significant correlations within each sex for maternal effects on different traits, indicative of trade-offs between development rate and adult size. By contrast, there was no evidence of any consistency in maternal effects on sons and daughters. This suggests that the evolution of maternal effects will follow independent trajectories dependent on sex-specific selection on offspring. Importantly, failure to recognize the sex-specific nature of maternal effects in this population would have substantially underestimated the extent of their variation between mothers. PMID:26289441

  2. Sex-specific maternal effects in a viviparous fish.

    PubMed

    Kruuk, Loeske E B; Livingston, Julianne; Kahn, Andrew; Jennions, Michael D

    2015-08-01

    Mothers vary in their effects on their offspring, but studies of variation in maternal effects rarely ask whether differences between mothers are consistent for sons and daughters. Here, we analysed maternal effects in the mosquitofish Gambusia holbrooki for development time and adult size of sons and daughters, and a primary male sexual character (gonopodium length). We found substantial maternal effects on all traits, most notably for gonopodium length. There were significant correlations within each sex for maternal effects on different traits, indicative of trade-offs between development rate and adult size. By contrast, there was no evidence of any consistency in maternal effects on sons and daughters. This suggests that the evolution of maternal effects will follow independent trajectories dependent on sex-specific selection on offspring. Importantly, failure to recognize the sex-specific nature of maternal effects in this population would have substantially underestimated the extent of their variation between mothers. PMID:26289441

  3. Food stress causes sex-specific maternal effects in mites.

    PubMed

    Walzer, Andreas; Schausberger, Peter

    2015-08-01

    Life history theory predicts that females should produce few large eggs under food stress and many small eggs when food is abundant. We tested this prediction in three female-biased size-dimorphic predatory mites feeding on herbivorous spider mite prey: Phytoseiulus persimilis, a specialized spider mite predator; Neoseiulus californicus, a generalist preferring spider mites; Amblyseius andersoni, a broad diet generalist. Irrespective of predator species and offspring sex, most females laid only one small egg under severe food stress. Irrespective of predator species, the number of female but not male eggs decreased with increasing maternal food stress. This sex-specific effect was probably due to the higher production costs of large female than small male eggs. The complexity of the response to the varying availability of spider mite prey correlated with the predators' degree of adaptation to this prey. Most A. andersoni females did not oviposit under severe food stress, whereas N. californicus and P. persimilis did oviposit. Under moderate food stress, only P. persimilis increased its investment per offspring, at the expense of egg number, and produced few large female eggs. When prey was abundant, P. persimilis decreased the female egg sizes at the expense of increased egg numbers, resulting in a sex-specific egg size/number trade-off. Maternal effects manifested only in N. californicus and P. persimilis. Small egg size correlated with the body size of daughters but not sons. Overall, our study provides a key example of sex-specific maternal effects, i.e. food stress during egg production more strongly affects the sex of the large than the small offspring. PMID:26089530

  4. Food stress causes sex-specific maternal effects in mites

    PubMed Central

    Walzer, Andreas; Schausberger, Peter

    2015-01-01

    ABSTRACT Life history theory predicts that females should produce few large eggs under food stress and many small eggs when food is abundant. We tested this prediction in three female-biased size-dimorphic predatory mites feeding on herbivorous spider mite prey: Phytoseiulus persimilis, a specialized spider mite predator; Neoseiulus californicus, a generalist preferring spider mites; Amblyseius andersoni, a broad diet generalist. Irrespective of predator species and offspring sex, most females laid only one small egg under severe food stress. Irrespective of predator species, the number of female but not male eggs decreased with increasing maternal food stress. This sex-specific effect was probably due to the higher production costs of large female than small male eggs. The complexity of the response to the varying availability of spider mite prey correlated with the predators' degree of adaptation to this prey. Most A. andersoni females did not oviposit under severe food stress, whereas N. californicus and P. persimilis did oviposit. Under moderate food stress, only P. persimilis increased its investment per offspring, at the expense of egg number, and produced few large female eggs. When prey was abundant, P. persimilis decreased the female egg sizes at the expense of increased egg numbers, resulting in a sex-specific egg size/number trade-off. Maternal effects manifested only in N. californicus and P. persimilis. Small egg size correlated with the body size of daughters but not sons. Overall, our study provides a key example of sex-specific maternal effects, i.e. food stress during egg production more strongly affects the sex of the large than the small offspring. PMID:26089530

  5. Sex-Specific Parental Effects on Offspring Lipid Levels

    PubMed Central

    Predazzi, Irene M; Sobota, Rafal S; Sanna, Serena; Bush, William S; Bartlett, Jacquelaine; Lilley, Jessica S; Linton, MacRae F; Schlessinger, David; Cucca, Francesco; Fazio, Sergio; Williams, Scott M

    2015-01-01

    Background Plasma lipid levels are highly heritable traits, but known genetic loci can only explain a small portion of their heritability. Methods and Results In this study, we analyzed the role of parental levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TGs) in explaining the values of the corresponding traits in adult offspring. We also evaluated the contribution of nongenetic factors that influence lipid traits (age, body mass index, smoking, medications, and menopause) alone and in combination with variability at the genetic loci known to associate with TC, LDL-C, HDL-C, and TG levels. We performed comparisons among different sex-specific regression models in 416 families from the Framingham Heart Study and 304 from the SardiNIA cohort. Models including parental lipid levels explain significantly more of the trait variation than models without these measures, explaining up to ≈39% of the total trait variation. Of this variation, the parent-of-origin effect explains as much as ≈15% and it does so in a sex-specific way. This observation is not owing to shared environment, given that spouse-pair correlations were negligible (<1.5% explained variation in all cases) and is distinct from previous genetic and acquired factors that are known to influence serum lipid levels. Conclusions These findings support the concept that unknown genetic and epigenetic contributors are responsible for most of the heritable component of the plasma lipid phenotype, and that, at present, the clinical utility of knowing age-matched parental lipid levels in assessing risk of dyslipidemia supersedes individual locus effects. Our results support the clinical utility of knowing parental lipid levels in assessing future risk of dyslipidemia. PMID:26126546

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

    PubMed

    Romani, William A; Russ, David W

    2013-10-01

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

  7. Sex-specific tissue weighting factors for effective dose equivalent calculations

    SciTech Connect

    Xu, X.G.; Reece, W.D.

    1996-01-01

    The effective dose equivalent was defined in the International Commission on Radiological Protection Publication 26 in 1977 and later adopted by the U.S. Nuclear REgulatory Commission. To calculate organ doses and effective dose equivalent for external exposures using Monte Carlo simulations, sex-specific anthropomorphic phantoms and sex-specific weighting factors are always employed. This paper presents detailed mathematical derivation of a set of sex-specific tissue weighting factors and the conditions which the weighting factors must satisfy. Results of effective dose equivalent calculations using female and male phantoms exposed to monoenergetic photon beams of 0.08, 0.3, and 1.0 MeV are provided and compared with results published by other authors using different sex-specific weighting factors and phantoms. The results indicate that females always receive higher effective dose equivalent than males for the photon energies and geometries considered and that some published data may be wrong due to mistakes in deriving the sex-specific weighting factors. 17 refs., 2 figs., 2 tabs.

  8. Postzygotic isolation involves strong mitochondrial and sex-specific effects in Tigriopus californicus, a species lacking heteromorphic sex chromosomes.

    PubMed

    Foley, B R; Rose, C G; Rundle, D E; Leong, W; Edmands, S

    2013-11-01

    Detailed studies of the genetics of speciation have focused on a few model systems, particularly Drosophila. The copepod Tigriopus californicus offers an alternative that differs from standard animal models in that it lacks heteromorphic chromosomes (instead, sex determination is polygenic) and has reduced opportunities for sexual conflict, because females mate only once. Quantitative trait loci (QTL) mapping was conducted on reciprocal F2 hybrids between two strongly differentiated populations, using a saturated linkage map spanning all 12 autosomes and the mitochondrion. By comparing sexes, a possible sex ratio distorter was found but no sex chromosomes. Although studies of standard models often find an excess of hybrid male sterility factors, we found no QTL for sterility and multiple QTL for hybrid viability (indicated by non-Mendelian adult ratios) and other characters. Viability problems were found to be stronger in males, but the usual explanations for weaker hybrid males (sex chromosomes, sensitivity of spermatogenesis, sexual selection) cannot fully account for these male viability problems. Instead, higher metabolic rates may amplify deleterious effects in males. Although many studies of standard speciation models find the strongest genetic incompatibilities to be nuclear-nuclear (specifically X chromosome-autosome), we found the strongest deleterious interaction in this system was mito-nuclear. Consistent with the snowball theory of incompatibility accumulation, we found that trigenic interactions in this highly divergent cross were substantially more frequent (>6×) than digenic interactions. This alternative system thus allows important comparisons to studies of the genetics of reproductive isolation in more standard model systems. PMID:23860232

  9. Postzygotic isolation involves strong mitochondrial and sex-specific effects in Tigriopus californicus, a species lacking heteromorphic sex chromosomes

    PubMed Central

    Foley, B R; Rose, C G; Rundle, D E; Leong, W; Edmands, S

    2013-01-01

    Detailed studies of the genetics of speciation have focused on a few model systems, particularly Drosophila. The copepod Tigriopus californicus offers an alternative that differs from standard animal models in that it lacks heteromorphic chromosomes (instead, sex determination is polygenic) and has reduced opportunities for sexual conflict, because females mate only once. Quantitative trait loci (QTL) mapping was conducted on reciprocal F2 hybrids between two strongly differentiated populations, using a saturated linkage map spanning all 12 autosomes and the mitochondrion. By comparing sexes, a possible sex ratio distorter was found but no sex chromosomes. Although studies of standard models often find an excess of hybrid male sterility factors, we found no QTL for sterility and multiple QTL for hybrid viability (indicated by non-Mendelian adult ratios) and other characters. Viability problems were found to be stronger in males, but the usual explanations for weaker hybrid males (sex chromosomes, sensitivity of spermatogenesis, sexual selection) cannot fully account for these male viability problems. Instead, higher metabolic rates may amplify deleterious effects in males. Although many studies of standard speciation models find the strongest genetic incompatibilities to be nuclear–nuclear (specifically X chromosome–autosome), we found the strongest deleterious interaction in this system was mito–nuclear. Consistent with the snowball theory of incompatibility accumulation, we found that trigenic interactions in this highly divergent cross were substantially more frequent (>6 × ) than digenic interactions. This alternative system thus allows important comparisons to studies of the genetics of reproductive isolation in more standard model systems. PMID:23860232

  10. Direct and indirect genetic effects of sex-specific mitonuclear epistasis on reproductive ageing.

    PubMed

    Immonen, E; Collet, M; Goenaga, J; Arnqvist, G

    2016-03-01

    Mitochondria are involved in ageing and their function requires coordinated action of both mitochondrial and nuclear genes. Epistasis between the two genomes can influence lifespan but whether this also holds for reproductive senescence is unclear. Maternal inheritance of mitochondria predicts sex differences in the efficacy of selection on mitonuclear genotypes that should result in differences between females and males in mitochondrial genetic effects. Mitonuclear genotype of a focal individual may also indirectly affect trait expression in the mating partner. We tested these predictions in the seed beetle Callosobruchus maculatus, using introgression lines harbouring distinct mitonuclear genotypes. Our results reveal both direct and indirect sex-specific effects of mitonuclear epistasis on reproductive ageing. Females harbouring coadapted mitonuclear genotypes showed higher lifetime fecundity due to slower senescence relative to novel mitonuclear combinations. We found no evidence for mitonuclear coadaptation in males. Mitonuclear epistasis not only affected age-specific ejaculate weight, but also influenced male age-dependent indirect effects on traits expressed by their female partners (fecundity, egg size, longevity). These results demonstrate important consequences of sex-specific mitonuclear epistasis for both mating partners, consistent with a role for mitonuclear genetic constraints upon sex-specific adaptive evolution. PMID:26732015

  11. Age- and sex-specific causal effects of adiposity on cardiovascular risk factors.

    PubMed

    Fall, Tove; Hägg, Sara; Ploner, Alexander; Mägi, Reedik; Fischer, Krista; Draisma, Harmen H M; Sarin, Antti-Pekka; Benyamin, Beben; Ladenvall, Claes; Åkerlund, Mikael; Kals, Mart; Esko, Tõnu; Nelson, Christopher P; Kaakinen, Marika; Huikari, Ville; Mangino, Massimo; Meirhaeghe, Aline; Kristiansson, Kati; Nuotio, Marja-Liisa; Kobl, Michael; Grallert, Harald; Dehghan, Abbas; Kuningas, Maris; de Vries, Paul S; de Bruijn, Renée F A G; Willems, Sara M; Heikkilä, Kauko; Silventoinen, Karri; Pietiläinen, Kirsi H; Legry, Vanessa; Giedraitis, Vilmantas; Goumidi, Louisa; Syvänen, Ann-Christine; Strauch, Konstantin; Koenig, Wolfgang; Lichtner, Peter; Herder, Christian; Palotie, Aarno; Menni, Cristina; Uitterlinden, André G; Kuulasmaa, Kari; Havulinna, Aki S; Moreno, Luis A; Gonzalez-Gross, Marcela; Evans, Alun; Tregouet, David-Alexandre; Yarnell, John W G; Virtamo, Jarmo; Ferrières, Jean; Veronesi, Giovanni; Perola, Markus; Arveiler, Dominique; Brambilla, Paolo; Lind, Lars; Kaprio, Jaakko; Hofman, Albert; Stricker, Bruno H; van Duijn, Cornelia M; Ikram, M Arfan; Franco, Oscar H; Cottel, Dominique; Dallongeville, Jean; Hall, Alistair S; Jula, Antti; Tobin, Martin D; Penninx, Brenda W; Peters, Annette; Gieger, Christian; Samani, Nilesh J; Montgomery, Grant W; Whitfield, John B; Martin, Nicholas G; Groop, Leif; Spector, Tim D; Magnusson, Patrik K; Amouyel, Philippe; Boomsma, Dorret I; Nilsson, Peter M; Järvelin, Marjo-Riitta; Lyssenko, Valeriya; Metspalu, Andres; Strachan, David P; Salomaa, Veikko; Ripatti, Samuli; Pedersen, Nancy L; Prokopenko, Inga; McCarthy, Mark I; Ingelsson, Erik

    2015-05-01

    Observational studies have reported different effects of adiposity on cardiovascular risk factors across age and sex. Since cardiovascular risk factors are enriched in obese individuals, it has not been easy to dissect the effects of adiposity from those of other risk factors. We used a Mendelian randomization approach, applying a set of 32 genetic markers to estimate the causal effect of adiposity on blood pressure, glycemic indices, circulating lipid levels, and markers of inflammation and liver disease in up to 67,553 individuals. All analyses were stratified by age (cutoff 55 years of age) and sex. The genetic score was associated with BMI in both nonstratified analysis (P = 2.8 × 10(-107)) and stratified analyses (all P < 3.3 × 10(-30)). We found evidence of a causal effect of adiposity on blood pressure, fasting levels of insulin, C-reactive protein, interleukin-6, HDL cholesterol, and triglycerides in a nonstratified analysis and in the <55-year stratum. Further, we found evidence of a smaller causal effect on total cholesterol (P for difference = 0.015) in the ≥55-year stratum than in the <55-year stratum, a finding that could be explained by biology, survival bias, or differential medication. In conclusion, this study extends previous knowledge of the effects of adiposity by providing sex- and age-specific causal estimates on cardiovascular risk factors. PMID:25712996

  12. Age- and Sex-Specific Causal Effects of Adiposity on Cardiovascular Risk Factors

    PubMed Central

    Fall, Tove; Hägg, Sara; Ploner, Alexander; Mägi, Reedik; Fischer, Krista; Draisma, Harmen H.M.; Sarin, Antti-Pekka; Benyamin, Beben; Ladenvall, Claes; Åkerlund, Mikael; Kals, Mart; Esko, Tõnu; Nelson, Christopher P.; Kaakinen, Marika; Huikari, Ville; Mangino, Massimo; Meirhaeghe, Aline; Kristiansson, Kati; Nuotio, Marja-Liisa; Kobl, Michael; Grallert, Harald; Dehghan, Abbas; Kuningas, Maris; de Vries, Paul S.; de Bruijn, Renée F.A.G.; Willems, Sara M.; Heikkilä, Kauko; Silventoinen, Karri; Pietiläinen, Kirsi H.; Legry, Vanessa; Giedraitis, Vilmantas; Goumidi, Louisa; Syvänen, Ann-Christine; Strauch, Konstantin; Koenig, Wolfgang; Lichtner, Peter; Herder, Christian; Palotie, Aarno; Menni, Cristina; Uitterlinden, André G.; Kuulasmaa, Kari; Havulinna, Aki S.; Moreno, Luis A.; Gonzalez-Gross, Marcela; Evans, Alun; Tregouet, David-Alexandre; Yarnell, John W.G.; Virtamo, Jarmo; Ferrières, Jean; Veronesi, Giovanni; Perola, Markus; Arveiler, Dominique; Brambilla, Paolo; Lind, Lars; Kaprio, Jaakko; Hofman, Albert; Stricker, Bruno H.; van Duijn, Cornelia M.; Ikram, M. Arfan; Franco, Oscar H.; Cottel, Dominique; Dallongeville, Jean; Hall, Alistair S.; Jula, Antti; Tobin, Martin D.; Penninx, Brenda W.; Peters, Annette; Gieger, Christian; Samani, Nilesh J.; Montgomery, Grant W.; Whitfield, John B.; Martin, Nicholas G.; Groop, Leif; Spector, Tim D.; Magnusson, Patrik K.; Amouyel, Philippe; Boomsma, Dorret I.; Nilsson, Peter M.; Järvelin, Marjo-Riitta; Lyssenko, Valeriya; Metspalu, Andres; Strachan, David P.; Salomaa, Veikko; Ripatti, Samuli; Pedersen, Nancy L.; Prokopenko, Inga; McCarthy, Mark I.

    2015-01-01

    Observational studies have reported different effects of adiposity on cardiovascular risk factors across age and sex. Since cardiovascular risk factors are enriched in obese individuals, it has not been easy to dissect the effects of adiposity from those of other risk factors. We used a Mendelian randomization approach, applying a set of 32 genetic markers to estimate the causal effect of adiposity on blood pressure, glycemic indices, circulating lipid levels, and markers of inflammation and liver disease in up to 67,553 individuals. All analyses were stratified by age (cutoff 55 years of age) and sex. The genetic score was associated with BMI in both nonstratified analysis (P = 2.8 × 10−107) and stratified analyses (all P < 3.3 × 10−30). We found evidence of a causal effect of adiposity on blood pressure, fasting levels of insulin, C-reactive protein, interleukin-6, HDL cholesterol, and triglycerides in a nonstratified analysis and in the <55-year stratum. Further, we found evidence of a smaller causal effect on total cholesterol (P for difference = 0.015) in the ≥55-year stratum than in the <55-year stratum, a finding that could be explained by biology, survival bias, or differential medication. In conclusion, this study extends previous knowledge of the effects of adiposity by providing sex- and age-specific causal estimates on cardiovascular risk factors. PMID:25712996

  13. Sex-specific effects of chronic fluoxetine treatment on neuroplasticity and pharmacokinetics in mice.

    PubMed

    Hodes, Georgia E; Hill-Smith, Tiffany E; Suckow, Raymond F; Cooper, Thomas B; Lucki, Irwin

    2010-01-01

    Neurogenesis is a mechanism through which antidepressants may produce therapeutic effects. There is a dearth of information regarding the effects of antidepressants on neurogenesis and neurotrophin mobilization in females. This study examined sex differences in the alteration of cell proliferation and survival in multiple regions of the brain. Additional experiments examined brain-derived neurotrophic factor (BDNF) levels and pharmacokinetics of fluoxetine to determine whether they mediate sex differences. MRL/MpJ mice were treated with fluoxetine (5 and 10 mg/kg b.i.d.) for 21 days and received injections of 5-bromo-2'-deoxyuridine (200 mg/kg) to measure DNA synthesis. In the hippocampus, fluoxetine increased cell proliferation at both doses; females treated with 10 mg/kg produced more new cells than males. Fluoxetine did not alter survival in males, but 10 mg/kg reduced survival in females. In the frontal cortex, fluoxetine increased cell proliferation and survival in males treated with 10 mg/kg. In the cerebellum and amygdala, 10 mg/kg fluoxetine increased cell proliferation in both sexes but did not alter the incorporation of the new cells. Fluoxetine increased BDNF levels in the hippocampus of both sexes. BDNF levels correlated with cell proliferation in males but not females. Brain and plasma levels indicated that females metabolized fluoxetine faster than males and produced more of the metabolite norfluoxetine. These data suggest that fluoxetine acts on multiple areas of the brain to increase cell proliferation, and the pattern of activation differs between males and females. Sex-specific effects of fluoxetine on neurotrophin mobilization and pharmacokinetics may contribute to these differences in neural plasticity. PMID:19828877

  14. Density-dependent effects on group size are sex-specific in a gregarious ungulate.

    PubMed

    Vander Wal, Eric; van Beest, Floris M; Brook, Ryan K

    2013-01-01

    Density dependence can have marked effects on social behaviors such as group size. We tested whether changes in population density of a large herbivore (elk, Cervus canadensis) affected sex-specific group size and whether the response was density- or frequency-dependent. We quantified the probability and strength of changes in group sizes and dispersion as population density changed for each sex. We used group size data from a population of elk in Manitoba, Canada, that was experimentally reduced from 1.20 to 0.67 elk/km(2) between 2002 and 2009. Our results indicated that functional responses of group size to population density are sex-specific. Females showed a positive density-dependent response in group size at population densities ≥0.70 elk/km(2) and we found evidence for a minimum group size at population density ≤0.70 elk/km(2). Changes in male group size were also density-dependent; however, the strength of the relationship was lower than for females. Density dependence in male group size was predominantly a result of fusion of solitary males into larger groups, rather than fusion among existing groups. Our study revealed that density affects group size of a large herbivore differently between males and females, which has important implications for the benefits e.g., alleviating predation risk, and costs of social behaviors e.g., competition for resources and mates, and intra-specific pathogen transmission. PMID:23326502

  15. Density-Dependent Effects on Group Size Are Sex-Specific in a Gregarious Ungulate

    PubMed Central

    Vander Wal, Eric; van Beest, Floris M.; Brook, Ryan K.

    2013-01-01

    Density dependence can have marked effects on social behaviors such as group size. We tested whether changes in population density of a large herbivore (elk, Cervus canadensis) affected sex-specific group size and whether the response was density- or frequency-dependent. We quantified the probability and strength of changes in group sizes and dispersion as population density changed for each sex. We used group size data from a population of elk in Manitoba, Canada, that was experimentally reduced from 1.20 to 0.67 elk/km2 between 2002 and 2009. Our results indicated that functional responses of group size to population density are sex-specific. Females showed a positive density-dependent response in group size at population densities ≥0.70 elk/km2 and we found evidence for a minimum group size at population density ≤0.70 elk/km2. Changes in male group size were also density-dependent; however, the strength of the relationship was lower than for females. Density dependence in male group size was predominantly a result of fusion of solitary males into larger groups, rather than fusion among existing groups. Our study revealed that density affects group size of a large herbivore differently between males and females, which has important implications for the benefits e.g., alleviating predation risk, and costs of social behaviors e.g., competition for resources and mates, and intra-specific pathogen transmission. PMID:23326502

  16. Genetic and Sex-Specific Transgenerational Effects of a High Fat Diet in Drosophila melanogaster.

    PubMed

    Dew-Budd, Kelly; Jarnigan, Julie; Reed, Laura K

    2016-01-01

    An organism's phenotype is the product of its environment and genotype, but an ancestor's environment can also be a contributing factor. The recent increase in caloric intake and decrease in physical activity of developed nations' populations is contributing to deteriorating health and making the study of the longer term impacts of a changing lifestyle a priority. The dietary habits of ancestors have been shown to affect phenotype in several organisms, including humans, mice, and the fruit fly. Whether the ancestral dietary effect is purely environmental or if there is a genetic interaction with the environment passed down for multiple generations, has not been determined previously. Here we used the fruit fly, Drosophila melanogaster, to investigate the genetic, sex-specific, and environmental effects of a high fat diet for three generations' on pupal body weights across ten genotypes. We also tested for genotype-specific transgenerational effects on metabolic pools and egg size across three genotypes. We showed that there were substantial differences in transgenerational responses to ancestral diet between genotypes and sexes through both first and second descendant generations. Additionally, there were differences in phenotypes between maternally and paternally inherited dietary effects. We also found a treated organism's reaction to a high fat diet was not a consistent predictor of its untreated descendants' phenotype. The implication of these results is that, given our interest in understanding and preventing metabolic diseases like obesity, we need to consider the contribution of ancestral environmental experiences. However, we need to be cautious when drawing population-level generalization from small studies because transgenerational effects are likely to exhibit substantial sex and genotype specificity. PMID:27518304

  17. Genetic and Sex-Specific Transgenerational Effects of a High Fat Diet in Drosophila melanogaster

    PubMed Central

    Dew-Budd, Kelly; Jarnigan, Julie

    2016-01-01

    An organism's phenotype is the product of its environment and genotype, but an ancestor’s environment can also be a contributing factor. The recent increase in caloric intake and decrease in physical activity of developed nations' populations is contributing to deteriorating health and making the study of the longer term impacts of a changing lifestyle a priority. The dietary habits of ancestors have been shown to affect phenotype in several organisms, including humans, mice, and the fruit fly. Whether the ancestral dietary effect is purely environmental or if there is a genetic interaction with the environment passed down for multiple generations, has not been determined previously. Here we used the fruit fly, Drosophila melanogaster, to investigate the genetic, sex-specific, and environmental effects of a high fat diet for three generations’ on pupal body weights across ten genotypes. We also tested for genotype-specific transgenerational effects on metabolic pools and egg size across three genotypes. We showed that there were substantial differences in transgenerational responses to ancestral diet between genotypes and sexes through both first and second descendant generations. Additionally, there were differences in phenotypes between maternally and paternally inherited dietary effects. We also found a treated organism’s reaction to a high fat diet was not a consistent predictor of its untreated descendants’ phenotype. The implication of these results is that, given our interest in understanding and preventing metabolic diseases like obesity, we need to consider the contribution of ancestral environmental experiences. However, we need to be cautious when drawing population-level generalization from small studies because transgenerational effects are likely to exhibit substantial sex and genotype specificity. PMID:27518304

  18. Sex-Specific Audience Effect in the Context of Mate Choice in Zebra Finches.

    PubMed

    Kniel, Nina; Bender, Stefanie; Witte, Klaudia

    2016-01-01

    Animals observing conspecifics during mate choice can gain additional information about potential mates. However, the presence of an observer, if detected by the observed individuals, can influence the nature of the behavior of the observed individuals, called audience effect. In zebra finches (Taeniopygia guttata castanotis), domesticated males show an audience effect during mate choice. However, whether male and female descendants of the wild form show an audience effect during mate choice is unknown. Therefore, we conducted an experiment where male and female focal birds could choose between two distinctive phenotypes of the opposite sex, an artificially adorned stimulus bird with a red feather on the forehead and an unadorned stimulus bird, two times consecutively, once without an audience and once with an audience bird (same sex as test bird). Males showed an audience effect when an audience male was present and spent more time with adorned and less time with unadorned females compared to when there was no audience present. The change in time spent with the respective stimulus females was positively correlated with the time that the audience male spent in front of its cage close to the focal male. Females showed no change in mate choice when an audience female was present, but their motivation to associate with both stimulus males decreased. In a control for mate-choice consistency there was no audience in either test. Here, both focal females and focal males chose consistently without a change in choosing motivation. Our results showed that there is an audience effect on mate choice in zebra finches and that the response to a same-sex audience was sex-specific. PMID:26839957

  19. Sex-Specific Audience Effect in the Context of Mate Choice in Zebra Finches

    PubMed Central

    Kniel, Nina; Bender, Stefanie; Witte, Klaudia

    2016-01-01

    Animals observing conspecifics during mate choice can gain additional information about potential mates. However, the presence of an observer, if detected by the observed individuals, can influence the nature of the behavior of the observed individuals, called audience effect. In zebra finches (Taeniopygia guttata castanotis), domesticated males show an audience effect during mate choice. However, whether male and female descendants of the wild form show an audience effect during mate choice is unknown. Therefore, we conducted an experiment where male and female focal birds could choose between two distinctive phenotypes of the opposite sex, an artificially adorned stimulus bird with a red feather on the forehead and an unadorned stimulus bird, two times consecutively, once without an audience and once with an audience bird (same sex as test bird). Males showed an audience effect when an audience male was present and spent more time with adorned and less time with unadorned females compared to when there was no audience present. The change in time spent with the respective stimulus females was positively correlated with the time that the audience male spent in front of its cage close to the focal male. Females showed no change in mate choice when an audience female was present, but their motivation to associate with both stimulus males decreased. In a control for mate-choice consistency there was no audience in either test. Here, both focal females and focal males chose consistently without a change in choosing motivation. Our results showed that there is an audience effect on mate choice in zebra finches and that the response to a same-sex audience was sex-specific. PMID:26839957

  20. Prenatal ethanol exposure has sex-specific effects on hippocampal long-term potentiation.

    PubMed

    Sickmann, H M; Patten, A R; Morch, K; Sawchuk, S; Zhang, C; Parton, R; Szlavik, L; Christie, B R

    2014-01-01

    Alcohol consumption during pregnancy is deleterious to the developing brain of the fetus and leads to persistent deficits in adulthood. Long-term potentiation (LTP) is a biological model for learning and memory processes and previous evidence has shown that prenatal ethanol exposure (PNEE) affects LTP in a sex specific manner during adolescence. The objective of this study was to determine if there are sex specific differences in adult animals and to elucidate the underlying molecular mechanisms that contribute to these differences. Pregnant Sprague-Dawley dams were assigned to either; liquid ethanol, pair-fed or standard chow diet. In vivo electrophysiology was performed in the hippocampal dentate gyrus (DG) of adult offspring. LTP was induced by administering 400 Hz stimuli. Western blot analysis for glutamine synthetase (GS) and glutamate decarboxylase from tissue of the DG indicated that GS expression was increased following PNEE. Surprisingly, adult females did not show any deficit in N-methyl-D-aspartate (NMDA)-dependent LTP after PNEE. In contrast, males showed a 40% reduction in LTP. It was indicated that glutamine synthetase expression was increased in PNEE females, suggesting that altered excitatory neurotransmitter replenishment may serve as a compensatory mechanism. Ovariectomizing females did not influence LTP in control or PNEE animals, suggesting that circulating estradiol levels do not play a major role in maintaining LTP levels in PNEE females. These results demonstrate the sexually dimorphic effects of PNEE on the ability for the adult brain to elicit LTP in the DG. The mechanisms for these effects are not fully understood, but an increase in glutamine synthetase in females may underlie this phenomenon. PMID:23996604

  1. Hypothalamic oxytocin and vasopressin neurons exert sex-specific effects on pair bonding, gregariousness, and aggression in finches.

    PubMed

    Kelly, Aubrey M; Goodson, James L

    2014-04-22

    Antagonism of oxytocin (OT) receptors (OTRs) impairs the formation of pair bonds in prairie voles (Microtus ochrogaster) and zebra finches (Taenioypygia guttata), and also reduces the preference for the larger of two groups ("gregariousness") in finches. These effects tend to be stronger in females. The contributions of specific peptide cell groups to these processes remain unknown, however. This issue is complicated by the fact that OTRs in finches and voles bind not only forms of OT, but also vasopressin (VP), and >10 cell groups produce each peptide in any given species. Using RNA interference, we found that knockdown of VP and OT production in the paraventricular nucleus of the hypothalamus exerts diverse behavioral effects in zebra finches, most of which are sexually differentiated. Our data show that knockdown of VP production significantly reduces gregariousness in both sexes and exerts sex-specific effects on aggression directed toward opposite-sex birds (increases in males; decreases in females), whereas OT knockdown produces female-specific deficits in gregariousness, pair bonding, and nest cup ownership; reduces side-by-side perching in both sexes; modulates stress coping; and induces hyperphagia in males. These findings demonstrate that paraventricular neurons are major contributors to the effects of VP-OT peptides on pair bonding and gregariousness; reveal previously unknown effects of sex-specific peptide on opposite-sex aggression; and demonstrate a surprising lack of effects on same-sex aggression. Finally, the observed effects of OT knockdown on feeding and stress coping parallel findings in mammals, suggesting that OT modulation of these processes is evolutionarily conserved across the amniote vertebrate classes. PMID:24711411

  2. Sex-Specific Effects of Arsenic Exposure on the Trajectory and Function of the Gut Microbiome.

    PubMed

    Chi, Liang; Bian, Xiaoming; Gao, Bei; Ru, Hongyu; Tu, Pengcheng; Lu, Kun

    2016-06-20

    The gut microbiome is deeply involved in numerous aspects of human health; however, it can be readily perturbed by environmental toxicants, such as arsenic. Meanwhile, the interaction among host, gut microbiome, and xenobiotics is a very complex dynamic process. Previously, we have demonstrated that gut microbiome phenotypes driven by host genetics and bacterial infection affect the responses to arsenic exposure. The role of host sex in shaping the gut microbiome raises the question whether sex plays a role in exposure-induced microbiome responses. To examine this, we used 16S rRNA sequencing and metagenomics sequencing to analyze the changes of the gut microbiome and its associated functional metagenome in both female and male C57/BL6 mice. Our results clearly demonstrated that arsenic exposure perturbed the trajectory and function of the gut microbiome in a sex-specific manner. PMID:27268458

  3. Pain modality- and sex-specific effects of COMT genetic functional variants

    PubMed Central

    Belfer, Inna; Segall, Samantha K.; Lariviere, William R.; Smith, Shad B.; Dai, Feng; Slade, Gary G.; Rashid, Naim U.; Mogil, Jeffrey S.; Campbell, Claudia; Edwards, Robert; Liu, Qian; Bair, Eric; Maixner, William; Diatchenko, Luda

    2013-01-01

    The enzyme catechol-O-methyltransferase (COMT) metabolizes catecholamine neurotransmitters involved in a number of physiological functions including pain perception. Both human and mouse COMT genes possess functional polymorphisms contributing to inter-individual variability in pain phenotypes such as sensitivity to noxious stimuli, severity of clinical pain and response to pain treatment. In this study, we found that the effects of Comt functional variation in mice are modality-specific. Spontaneous inflammatory nociception and thermal nociception behaviors were correlated the most with the presence of the B2 SINE transposon insertion residing in the 3’UTR mRNA region. Similarly, in humans, COMT functional haplotypes were associated with thermal pain perception and with capsaicin-induced pain. Furthermore, COMT genetic variations contributed to pain behaviors in mice and pain ratings in humans in a sex-specific manner. The ancestral Comt variant, without a B2 SINE insertion, was more strongly associated with sensitivity to capsaicin in female versus male mice. In humans, the haplotype coding for low COMT activity increased capsaicin-induced pain perception in women, but not men. These findings reemphasize the fundamental contribution of COMT to pain processes, and provide a fine-grained resolution of this contribution at the genetic level that can be used to guide future studies in the area of pain genetics. PMID:23701723

  4. Effects of deltamethrin on the specific discrimination of sex pheromones in two sympatric Trichogramma species.

    PubMed

    Delpuech, Jean-Marie; Dupont, Carole; Allemand, Roland

    2012-10-01

    The large amounts of insecticides used for crop protection lead to widespread environmental pollution. Determination of the potential impacts induced by this contamination on key species involved in the equilibrium of ecosystems is therefore a necessity. In this study, we tested the effects of a pyrethroid insecticide, deltamethrin, on the capacity of males from two sympatric Trichogramma species to discriminate the sex pheromones emitted by females of their own species (Trichogramma are parasitoids of Lepidopterous). The impact of an acute exposure as could occur at field edges was evaluated using a dose inducing 20% mortality (LD 20). The impact of a low exposure corresponding to diffuse environmental pollution was evaluated by applying an LD 0.1 (a dose inducing no apparent mortality). For T. semblidis, deltamethrin decreased the specific recognition of sexual pheromones at the higher dose (LD 20) but had no effect on this recognition at the lower dose (LD 0.1). However, deltamethrin decreased the saturation of pheromone receptors at both doses. For T. evanescens, deltamethrin increased the recognition of sexual pheromones at both doses, though not during the same period of observation (at the beginning for the LD 20, at the end for the LD 0.1), but it did not decrease the saturation of the pheromone receptors. These differing results were analyzed considering the behavior of the insects, their level of sensitivity to the insecticide and its mode of action. They provide new insights regarding possible consequences of environmental pollution by insecticides on functional biodiversity. PMID:22885055

  5. Sex Specific Effect of Prenatal Testosterone on Language Lateralization in Children

    ERIC Educational Resources Information Center

    Lust, J. M.; Geuze, R. H.; Van de Beek, C.; Cohen-Kettenis, P. T.; Groothuis, A. G. G.; Bouma, A.

    2010-01-01

    Brain lateralization refers to the division of labour between the two hemispheres in controlling a wide array of functions and is remarkably well developed in humans. Based on sex differences in lateralization of handedness and language, several hypotheses have postulated an effect of prenatal exposure to testosterone on human lateralization…

  6. 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

  7. Repeated ketamine treatment induces sex-specific behavioral and neurochemical effects in mice.

    PubMed

    Thelen, Connor; Sens, Jonathon; Mauch, Joseph; Pandit, Radhika; Pitychoutis, Pothitos M

    2016-10-01

    One of the most striking discoveries in the treatment of major depression was the finding that infusion of a single sub-anesthetic dose of ketamine induces rapid and sustained antidepressant effects in treatment-resistant depressed patients. However, ketamine's antidepressant-like actions are transient and can only be sustained by repeated drug treatment. Despite the fact that women experience major depression at roughly twice the rate of men, research regarding the neurobiological antidepressant-relevant effects of ketamine has focused almost exclusively on the male sex. Importantly, knowledge regarding the sex-differentiated effects, the frequency and the dose on which repeated ketamine administration stops being beneficial, is limited. In the current study, we investigated the behavioral, neurochemical and synaptic molecular effects of repeated ketamine treatment (10mg/kg; 21days) in male and female C57BL/6J mice. We report that ketamine induced beneficial antidepressant-like effects in male mice, but induced both anxiety-like (i.e., decreased time spent in the center of the open field arena) and depressive-like effects (i.e., enhanced immobility duration in the forced swim test; FST) in their female counterparts. Moreover, repeated ketamine treatment induced sustained sex-differentiated neurochemical and molecular effects, as it enhanced hippocampal synapsin protein levels and serotonin turnover in males, but attenuated glutamate and aspartate levels in female mice. Taken together, our findings indicate that repeated ketamine treatment induces opposite behavioral effects in male and female mice, and thus, present data have far-reaching implications for the sex-oriented use of ketamine in both experimental and clinical research settings. PMID:27343934

  8. Valence-Specific Laterality Effects in Vocal Emotion: Interactions with Stimulus Type, Blocking and Sex

    ERIC Educational Resources Information Center

    Schepman, Astrid; Rodway, Paul; Geddes, Pauline

    2012-01-01

    Valence-specific laterality effects have been frequently obtained in facial emotion perception but not in vocal emotion perception. We report a dichotic listening study further examining whether valence-specific laterality effects generalise to vocal emotions. Based on previous literature, we tested whether valence-specific laterality effects were…

  9. Estimating the sex-specific effects of genes on facial attractiveness and sexual dimorphism.

    PubMed

    Mitchem, Dorian G; Purkey, Alicia M; Grebe, Nicholas M; Carey, Gregory; Garver-Apgar, Christine E; Bates, Timothy C; Arden, Rosalind; Hewitt, John K; Medland, Sarah E; Martin, Nicholas G; Zietsch, Brendan P; Keller, Matthew C

    2014-05-01

    Human facial attractiveness and facial sexual dimorphism (masculinity-femininity) are important facets of mate choice and are hypothesized to honestly advertise genetic quality. However, it is unclear whether genes influencing facial attractiveness and masculinity-femininity have similar, opposing, or independent effects across sex, and the heritability of these phenotypes is poorly characterized. To investigate these issues, we assessed facial attractiveness and facial masculinity-femininity in the largest genetically informative sample (n = 1,580 same- and opposite-sex twin pairs and siblings) to assess these questions to date. The heritability was ~0.50-0.70 for attractiveness and ~0.40-0.50 for facial masculinity-femininity, indicating that, despite ostensible selection on genes influencing these traits, substantial genetic variation persists in both. Importantly, we found evidence for intralocus sexual conflict, whereby alleles that increase masculinity in males have the same effect in females. Additionally, genetic influences on attractiveness were shared across the sexes, suggesting that attractive fathers tend to have attractive daughters and attractive mothers tend to have attractive sons. PMID:24213680

  10. 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

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

    PubMed

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

    2015-03-15

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

  12. Effect of parasitism on plasma sex-specific proteins in Cyphocarax gilbert (Teleost, Curimatidae).

    PubMed

    Da Silva, L Gomes; Azevedo, J S; Silva-Neto, M A; Lima, N R Wille; Dansa-Petretski, M

    2005-06-01

    Cyphocarax gilbert (Szidat, L., 1948) is a fish commonly found in coastal drainage of eastern Brazil. This fish is sometimes caught with signs of infection by the crustacean Riggia paranensis, a haematophagous parasite. A remarkable feature of infected fish is that they lack gonads. In this paper we have analysed the frequency of parasitism, the gonadal development of non-infected fish and the profile of plasma proteins in both infected and non-infected specimens. Two reproductive periods/year were observed, beginning in February and August. On average, 40% of fish were infected, in the Itabapoana River (Brazil). Sex-specific proteins were identified by electrophoresis. SDS-PAGE analysis demonstrated that a 143 kDa female-specific glycolipoprotein (FSP) is a calcium-binding phosphoprotein. FSP was isolated through ultracentrifugation and SDS-PAGE analysis showed that the native protein is composed of three polypeptides of 143, 100 and 70 kDa. Both FSP and a 33 kDa male-specific protein (MSP) are absent from infected fish plasma. FSP levels in female plasma changes with the developmental stage of gonads. Altogether these data suggest that the FSP corresponds to fish vitellogenin. Furthermore, the absence of the above-mentioned proteins in infected fish suggests that R. paranensis might interfere with the regular hormonal process of fish vitellogenesis. PMID:15977902

  13. Intensity of space use reveals conditional sex-specific effects of prey and conspecific density on home range size.

    PubMed

    Aronsson, Malin; Low, Matthew; López-Bao, José V; Persson, Jens; Odden, John; Linnell, John D C; Andrén, Henrik

    2016-05-01

    Home range (HR) size variation is often linked to resource abundance, with sex differences expected to relate to sex-specific fitness consequences. However, studies generally fail to disentangle the effects of the two main drivers of HR size variation, food and conspecific density, and rarely consider how their relative influence change over spatiotemporal scales. We used location data from 77 Eurasian lynx (Lynx lynx) from a 16-year Scandinavian study to examine HR sizes variation relative to prey and conspecific density at different spatiotemporal scales. By varying the isopleth parameter (intensity of use) defining the HR, we show that sex-specific effects were conditional on the spatial scale considered. Males had larger HRs than females in all seasons. Females' total HR size declined as prey and conspecific density increased, whereas males' total HR was only affected by conspecific density. However, as the intensity of use within the HR increased (from 90% to 50% isopleth), the relationship between prey density and area showed opposing patterns for females and males; for females, the prey density effect was reduced, while for males, prey became increasingly important. Thus, prey influenced the size of key regions within male HRs, despite total HR size being independent of prey density. Males reduced their HR size during the mating season, likely to remain close to individual females in estrous. Females reduced their HR size postreproduction probably because of movement constrains imposed by dependent young. Our findings highlight the importance of simultaneously considering resources and intraspecific interactions as HR size determinants. We show that sex-specific demands influence the importance of prey and conspecific density on space use at different spatiotemporal scales. Thus, unless a gradient of space use intensity is examined, factors not related to total HR size might be disregarded despite their importance in determining size of key regions within

  14. Sex-Specific and Estrous Cycle-Dependent Antidepressant-Like Effects and Hippocampal Akt Signaling of Leptin.

    PubMed

    Carrier, Nicole; Wang, Xuezhen; Sun, Linshan; Lu, Xin-Yun

    2015-10-01

    Sex differences in the incidence of depression and antidepressant treatment responses are well documented. Depression is twice as common in women as in men. Recent studies indicate that low levels of leptin, an adipocyte-derived hormone, are associated with increased symptoms of depression in women. Leptin has been shown to produce antidepressant-like effects in male rodents. In the present study, we examined sex differences and estrous cycle variations in antidepressant-like responses to leptin. Leptin administration significantly reduced immobility, a putative measure of behavioral despair, in the forced swim test in intact female mice in the proestrus phase but not in the diestrus phase of the estrous cycle. Moreover, leptin administration stimulated Akt phosphorylation in the hippocampus of female mice in proestrus but not in diestrus, in correlation with its differential behavioral effects in these two phases of the cycle. Leptin-induced behavioral responses and stimulation of hippocampal Akt phosphorylation in female mice were abolished by ovariectomy. By contrast, the antidepressant-like effect of leptin in male mice was not affected by gonadectomy (castration). Pretreatment with 17β-estradiol restored sensitivity to the effects of leptin on behavior and hippocampal Akt phosphorylation in ovariectomized female mice. These results suggest leptin regulates depression-like behavior and hippocampal Akt signaling in a sex-specific and estrous cycle-dependent manner. PMID:26181103

  15. The effects of exogenous putrescine on sex-specific responses of Populus cathayana to copper stress.

    PubMed

    Chen, Lianghua; Wang, Ling; Chen, Fugui; Korpelainen, Helena; Li, Chunyang

    2013-11-01

    We used the dioecious tree, Populus cathayana, as a model species to study plants' physiological and biochemical responses to copper (Cu) stress, exogenous putrescine (Put) treatment and their interaction. Although males accumulated higher Cu concentrations in leaves than did females under Cu stress, they did not suffer more damage than females, as reflected by changes in gas exchange, pigment contents, membrane lipid peroxidation (thiobarbituric acid reactive substances, TBARS) and protein oxidation (carbonyl). Higher Cu tolerance of males was correlated with a higher H2O2 scavenging ability and proline responses, and a better maintenance of non-protein thiols (NP-SHs) and spermine (Spm) contents. We also discovered that mitigation effects of exogenous Put on Cu stress occurred, as visible as a recovery of the total chlorophyll content, and lower TBARS and carbonyl under interaction treatment when compared to Cu stress alone. Exogenous Put decreased the Cu concentration in leaves of both sexes, but to different degrees. Such effects of exogenous Put suggested that Put may play important roles in the stabilization of membrane integrity and protein structures, and it may modulate the uptake and transportation of Cu. Our results indicated that (1) males are more tolerant to Cu stress than females; (2) Put could mitigate Cu toxicity in P. cathayana, but to a different degree in males and females; (3) males are better candidates than females for Cu extraction and phytoremediation. PMID:23938041

  16. Depot- and sex-specific effects of maternal obesity in offspring's adipose tissue.

    PubMed

    Lecoutre, Simon; Deracinois, Barbara; Laborie, Christine; Eberlé, Delphine; Guinez, Céline; Panchenko, Polina E; Lesage, Jean; Vieau, Didier; Junien, Claudine; Gabory, Anne; Breton, Christophe

    2016-07-01

    According to the Developmental Origin of Health and Disease (DOHaD) concept, alterations of nutrient supply in the fetus or neonate result in long-term programming of individual body weight (BW) setpoint. In particular, maternal obesity, excessive nutrition, and accelerated growth in neonates have been shown to sensitize offspring to obesity. The white adipose tissue may represent a prime target of metabolic programming induced by maternal obesity. In order to unravel the underlying mechanisms, we have developed a rat model of maternal obesity using a high-fat (HF) diet (containing 60% lipids) before and during gestation and lactation. At birth, newborns from obese dams (called HF) were normotrophs. However, HF neonates exhibited a rapid weight gain during lactation, a key period of adipose tissue development in rodents. In males, increased BW at weaning (+30%) persists until 3months of age. Nine-month-old HF male offspring was normoglycemic but showed mild glucose intolerance, hyperinsulinemia, and hypercorticosteronemia. Despite no difference in BW and energy intake, HF adult male offspring was predisposed to fat accumulation showing increased visceral (gonadal and perirenal) depots weights and hyperleptinemia. However, only perirenal adipose tissue depot exhibited marked adipocyte hypertrophy and hyperplasia with elevated lipogenic (i.e. sterol-regulated element binding protein 1 (Srebp1), fatty acid synthase (Fas), and leptin) and diminished adipogenic (i.e. peroxisome proliferator-activated receptor gamma (Pparγ), 11β-hydroxysteroid dehydrogenase type 1 (11β-Hds1)) mRNA levels. By contrast, very few metabolic variations were observed in HF female offspring. Thus, maternal obesity and accelerated growth during lactation program offspring for higher adiposity via transcriptional alterations of visceral adipose tissue in a depot- and sex-specific manner. PMID:27122310

  17. Sex-Specific Effects of Adiponectin on Carotid Intima-Media Thickness and Incident Cardiovascular Disease

    PubMed Central

    Persson, Jonas; Strawbridge, Rona J; McLeod, Olga; Gertow, Karl; Silveira, Angela; Baldassarre, Damiano; Van Zuydam, Natalie; Shah, Sonia; Fava, Cristiano; Gustafsson, Stefan; Veglia, Fabrizio; Sennblad, Bengt; Larsson, Malin; Sabater-Lleal, Maria; Leander, Karin; Gigante, Bruna; Tabak, Adam; Kivimaki, Mika; Kauhanen, Jussi; Rauramaa, Rainer; Smit, Andries J; Mannarino, Elmo; Giral, Philippe; Humphries, Steve E; Tremoli, Elena; de Faire, Ulf; Lind, Lars; Ingelsson, Erik; Hedblad, Bo; Melander, Olle; Kumari, Meena; Hingorani, Aroon; Morris, Andrew D; Palmer, Colin N A; Lundman, Pia; Öhrvik, John; Söderberg, Stefan; Hamsten, Anders

    2015-01-01

    Background Plasma adiponectin levels have previously been inversely associated with carotid intima-media thickness (IMT), a marker of subclinical atherosclerosis. In this study, we used a sex-stratified Mendelian randomization approach to investigate whether adiponectin has a causal protective influence on IMT. Methods and Results Baseline plasma adiponectin concentration was tested for association with baseline IMT, IMT progression over 30 months, and occurrence of cardiovascular events within 3 years in 3430 participants (women, n =1777; men, n =1653) with high cardiovascular risk but no prevalent disease. Plasma adiponectin levels were inversely associated with baseline mean bifurcation IMT after adjustment for established risk factors (β =−0.018, P<0.001) in men but not in women (β =−0.006, P =0.185; P for interaction =0.061). Adiponectin levels were inversely associated with progression of mean common carotid IMT in men (β =−0.0022, P =0.047), whereas no association was seen in women (0.0007, P =0.475; P for interaction =0.018). Moreover, we observed that adiponectin levels were inversely associated with coronary events in women (hazard ratio 0.57, 95% CI 0.37 to 0.87) but not in men (hazard ratio 0.82, 95% CI 0.54 to 1.25). A gene score of adiponectin-raising alleles in 6 loci, reported recently in a large multi-ethnic meta-analysis, was inversely associated with baseline mean bifurcation IMT in men (β =−0.0008, P =0.004) but not in women (β =−0.0003, P =0.522; P for interaction =0.007). Conclusions This report provides some evidence for adiponectin protecting against atherosclerosis, with effects being confined to men; however, compared with established cardiovascular risk factors, the effect of plasma adiponectin was modest. Further investigation involving mechanistic studies is warranted. PMID:26276317

  18. Sex-specific effects of early life stress on social interaction and prefrontal cortex dendritic morphology in young rats.

    PubMed

    Farrell, M R; Holland, F H; Shansky, R M; Brenhouse, H C

    2016-09-01

    Early life stress has been linked to depression, anxiety, and behavior disorders in adolescence and adulthood. The medial prefrontal cortex (mPFC) is implicated in stress-related psychopathology, is a target for stress hormones, and mediates social behavior. The present study investigated sex differences in early-life stress effects on juvenile social interaction and adolescent mPFC dendritic morphology in rats using a maternal separation (MS) paradigm. Half of the rat pups of each sex were separated from their mother for 4h a day between postnatal days 2 and 21, while the other half remained with their mother in the animal facilities and were exposed to minimal handling. At postnatal day 25 (P25; juvenility), rats underwent a social interaction test with an age and sex matched conspecific. Distance from conspecific, approach and avoidance behaviors, nose-to-nose contacts, and general locomotion were measured. Rats were euthanized at postnatal day 40 (P40; adolescence), and randomly selected infralimbic pyramidal neurons were filled with Lucifer yellow using iontophoretic microinjections, imaged in 3D, and then analyzed for dendritic arborization, spine density, and spine morphology. Early-life stress increased the latency to make nose-to-nose contact at P25 in females but not males. At P40, early-life stress increased infralimbic apical dendritic branch number and length and decreased thin spine density in stressed female rats. These results indicate that MS during the postnatal period influenced juvenile social behavior and mPFC dendritic arborization in a sex-specific manner. PMID:27180166

  19. Sex-specific effect of the anabolic steroid, 17α-methyltestosterone, on inhibitory avoidance learning in periadolescent rats

    PubMed Central

    Ramos-Pratts, Keyla; Rosa-González, Dariana; Pérez-Acevedo, Nivia L.; Cintrón-López, Dahima; Barreto-Estrada, Jennifer L.

    2013-01-01

    The illicit use of anabolic androgenic steroids (AAS) has gained popularity among adolescents in the last decade. However, although it is known that exposure to AAS impairs cognition in adult animal models, the cognitive effects during adolescence remain undetermined. An inhibitory avoidance task (IAT) was used to assess the effect of AAS (17α-methyltestosterone; 17α-meT-7.5 mg/kg) in male and female periadolescent rats. A single injection of 17α-meT immediately before the footshock produced significant impairment of inhibitory avoidance learning in males but not females. Generalized anxiety, locomotion, and risk assessment behaviors (RAB) were not affected. Our results show that exposure to a single pharmacological dose of 17α-meT during periadolescence exerts sex-specific cognitive effects without affecting anxiety. Thus, disruption of the hormonal milieu during this early developmental period might have negative impact on learning and memory. PMID:23792034

  20. Sex-Specificity in the Reward Value of Facial Attractiveness.

    PubMed

    Hahn, Amanda C; Fisher, Claire I; DeBruine, Lisa M; Jones, Benedict C

    2016-05-01

    Studies of the sex-specificity of sexual arousal in adults (i.e., the tendency to respond more strongly to preferred-sex individuals than non-preferred sex individuals) have suggested that heterosexual men, homosexual men, and homosexual women show stronger sex-specific responses than do heterosexual women. Evidence for a similar pattern of results in studies investigating the reward value of faces is equivocal. Consequently, we investigated the effects of (1) sexual orientation (homosexual vs. heterosexual), (2) sex (male vs. female), (3) image sex (preferred-sex vs. non-preferred-sex), and (4) the physical attractiveness of the individual shown in the image on the reward value of faces. Participants were 130 heterosexual men, 130 homosexual men, 130 heterosexual women, and 130 homosexual women. The reward value of faces was assessed using a standard key-press task. Multilevel modeling of responses indicated that images of preferred-sex individuals were more rewarding than images of non-preferred-sex individuals and that this preferred-sex bias was particularly pronounced when more physically attractive faces were presented. These effects were not qualified by interactions involving either the sexual orientation or the sex of our participants, however, suggesting that the preferred-sex bias in the reward value of faces is similar in heterosexual men, homosexual men, heterosexual women, and homosexual women. PMID:25868402

  1. Sex-Specific Effects of Diets High in Unsaturated Fatty Acids on Spatial Learning and Memory in Guinea Pigs.

    PubMed

    Nemeth, Matthias; Millesi, Eva; Wagner, Karl-Heinz; Wallner, Bernard

    2015-01-01

    Unsaturated fatty acids (UFAs), including omega-3, omega-6 polyunsaturated and omega-9 monounsaturated fatty acids, are essential components and modulators of neuromembranes and may affect various aspects of physiology and cognition. UFAs are suggested to positively affect spatial learning and memory and also to diminish the negative consequences of physiological stress on cognitive abilities. Due to pronounced sex differences in neurophysiological functions, we hypothesize that these UFA-related effects might differ between male and female individuals. We therefore determined the effects of dietary UFAs on cognitive performances in a radial-Y-maze in male and female guinea pigs in relation to saliva cortisol concentrations, a marker for physiological stress. Animals were assigned to four treatment groups and maintained on diets enriched in either chia seeds (omega-3), walnuts (omega-6), or peanuts (omega-9), or a control diet. Female learning abilities throughout a three-day learning phase were positively affected by omega-3 and omega-9, as determined by a decreasing latency to pass the test and the number of conducted errors, while males generally showed distinct learning abilities, irrespective of the diet. A sex difference in learning performances was found in the control group, with males outperforming females, which was not detected in the UFA-supplemented groups. This was paralleled by significantly increased saliva cortisol concentrations in males throughout the cognition test compared to females. Three days after this learning phase, UFA-supplemented males and all females showed unchanged performances, while control males showed an increased latency and therefore an impaired performance. These results were corroborated by pronounced differences in the plasma UFA-status, corresponding to the different dietary treatments. Our findings indicate sex-specific effects of dietary UFAs, apparently enhancing spatial learning abilities only in females and protecting

  2. Sex-Specific Effects of Diets High in Unsaturated Fatty Acids on Spatial Learning and Memory in Guinea Pigs

    PubMed Central

    Nemeth, Matthias; Millesi, Eva; Wagner, Karl-Heinz; Wallner, Bernard

    2015-01-01

    Unsaturated fatty acids (UFAs), including omega-3, omega-6 polyunsaturated and omega-9 monounsaturated fatty acids, are essential components and modulators of neuromembranes and may affect various aspects of physiology and cognition. UFAs are suggested to positively affect spatial learning and memory and also to diminish the negative consequences of physiological stress on cognitive abilities. Due to pronounced sex differences in neurophysiological functions, we hypothesize that these UFA-related effects might differ between male and female individuals. We therefore determined the effects of dietary UFAs on cognitive performances in a radial-Y-maze in male and female guinea pigs in relation to saliva cortisol concentrations, a marker for physiological stress. Animals were assigned to four treatment groups and maintained on diets enriched in either chia seeds (omega-3), walnuts (omega-6), or peanuts (omega-9), or a control diet. Female learning abilities throughout a three-day learning phase were positively affected by omega-3 and omega-9, as determined by a decreasing latency to pass the test and the number of conducted errors, while males generally showed distinct learning abilities, irrespective of the diet. A sex difference in learning performances was found in the control group, with males outperforming females, which was not detected in the UFA-supplemented groups. This was paralleled by significantly increased saliva cortisol concentrations in males throughout the cognition test compared to females. Three days after this learning phase, UFA-supplemented males and all females showed unchanged performances, while control males showed an increased latency and therefore an impaired performance. These results were corroborated by pronounced differences in the plasma UFA-status, corresponding to the different dietary treatments. Our findings indicate sex-specific effects of dietary UFAs, apparently enhancing spatial learning abilities only in females and protecting

  3. Sex-specific effects of intranasal oxytocin on autonomic nervous system and emotional responses to couple conflict

    PubMed Central

    Nater, Urs M.; Schaer, Marcel; La Marca, Roberto; Bodenmann, Guy; Ehlert, Ulrike; Heinrichs, Markus

    2013-01-01

    Unhappy couple relationships are associated with impaired individual health, an effect thought to be mediated through ongoing couple conflicts. Little is known, however, about the underlying mechanisms regulating psychobiological stress, and particularly autonomic nervous system (ANS) reactivity, during negative couple interaction. In this study, we tested the effects of the neuropeptide oxytocin on ANS reactivity during couple conflict in a standardized laboratory paradigm. In a double-blind, placebo-controlled design, 47 heterosexual couples (total n = 94) received oxytocin or placebo intranasally prior to instructed couple conflict. Participants’ behavior was videotaped and salivary alpha-amylase (sAA), a measure of sympathetic activity, and emotional arousal were repeatedly measured during the experiment. Oxytocin significantly reduced sAA during couple conflict in women, whereas men showed increases in sAA levels (sex × group interaction: B = −49.36, t = −2.68, P = 0.009). In men, these increases were related to augmented emotional arousal (r = 0.286, P = 0.028) and more positive behavior (r = 0.291, P = 0.026), whereas there was no such association in women. Our results imply sex-specific effects of oxytocin on sympathetic activity, to negative couple interaction, with the neuropeptide reducing sAA responses and emotional arousal in women while increasing them in men. PMID:22842905

  4. The effects of arbuscular mycorrhizal fungi on sex-specific responses to Pb pollution in Populus cathayana.

    PubMed

    Chen, Lianghua; Hu, Xiangwei; Yang, Wanqin; Xu, Zhenfeng; Zhang, Danju; Gao, Shun

    2015-03-01

    Using fast-growing trees to remediate soils polluted by heavy metals (HMs) has received increasingly more attention, especially for recalcitrant Pb, as one of the most seriously toxic HMs. However, little is known about the responses of plants to a diffused level of Pb pollution, and a more combined phytoremediation technique is needed to explore. In this study, an arbuscular mycorrhizal fungus (AMF), i.e., Funneliformis mosseae, isolated from Populus euphratica distributed in a tailing of Pb/Zn ore, was introduced to investigate its effects on sex-specific responses of P. cathayana in morphology, physiology, and Pb phytoremediation capacity, when exposed to a diffused level of Pb pollution (100mg Pb(2+) kg(-1) dry soil). Symbiosis with exotic AMF did not significantly affect growth of both sexes and biomass allocation. However, when inoculated with AMF, both sexes absorbed more P, but not N in the roots, especially when exposed to the exogenous addition of Pb. The improvement of nutrient status under such conditions might be associated with a further increase in activity of antioxidant enzymes (particularly for superoxide dismutase (SOD) and catalase (CAT)), and the mitigation of oxidation stress induced by excessive reactive oxygen species (ROS). We also observed that exotic AMF could promote the uptake and accumulation of Pb in roots of females, but not in that of males. Therefore, under this diffused pollution level, the infected females might be more suitable for remediation of this metal than infected males, due to the higher capacity of HM accumulation without obvious negative effects on growth and physiological traits. Moreover, field surveys are needed to testify our experimental results, due to diversity of soil microbial community and complexities of their interaction. PMID:25553418

  5. Parasites of Trinidadian guppies: evidence for sex- and age-specific trait-mediated indirect effects of predators.

    PubMed

    Stephenson, Jessica F; van Oosterhout, Cock; Mohammed, Ryan S; Cable, Joanne

    2015-02-01

    Predation pressure can alter the morphology, physiology, life history, and behavior of prey; each of these in turn can change how surviving prey interact with parasites. These trait-mediated indirect effects may change in direction or intensity during growth or, in sexually dimorphic species, between the sexes. The Trinidadian guppy, Poecilia reticulata presents a unique opportunity to examine these interactions; its behavioral ecology has been intensively studied in wild populations with well-characterized predator faunas. Predation pressure is known to have driven the evolution of many guppy traits; for example, in high-predation sites, females (but not males) tend to shoal, and this anti-predator behavior facilitates parasite transmission. To test for evidence of predator-driven differences in infection in natural populations, we collected 4715 guppies from 62 sites across Trinidad between 2003 and 2009 and screened them for ectosymbionts, including Gyrodactylus. A novel model-averaging analysis revealed that females were more likely to be infected with Gyrodactylus parasites than males, but only in populations with both high predation pressure and high infection prevalence. We propose that the difference in shoaling tendency between the sexes could explain the observed difference in infection prevalence between males and females in high-predation sites. The infection rate of juveniles did not vary with predation regime, probably because juveniles face constant predation pressure from conspecific adults and therefore tend to shoal in both high- and low-predation sites. This represents the first evidence for age- and sex-specific trait-mediated indirect effects of predators on the probability of infection in their prey. PMID:26240870

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

    PubMed

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

    2015-06-01

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

  7. Sex-specific effects of carotenoid intake on the immunological response to allografts in guppies (Poecilia reticulata).

    PubMed

    Grether, Gregory F; Kasahara, Shinji; Kolluru, Gita R; Cooper, Edwin L

    2004-01-01

    Rarely are the evolutionary origins of mate preferences known, but, recently, the preference of female guppies (Poecilia reticulata) for males with carotenoid-based sexual coloration has been linked to a sensory bias that may have originally evolved for detecting carotenoid-rich fruits. If carotenoids enhance the immune systems of these fishes, as has been suggested for other species, this could explain the origin of the attraction to orange fruits as well as the maintenance of the female preference for orange males. We used the classic immunological technique of tissue grafting to assay a component of the immune response of guppies raised on two different dietary levels of carotenoids. Individual scales were transplanted between pairs of unrelated fishes, creating reciprocal allografts. Transplanted scales were scored on a six-point rejection scale every day for 10 days. Five days later, the same pairs of fishes received a second set of allografts and were scored again. Compared with low-carotenoid-diet males, high-carotenoid-diet males mounted a significantly stronger rejection response to the second allograft but not to the first allograft. High-carotenoid-diet females, however, showed no improvement in graft rejection compared with low-carotenoid-diet females. To our knowledge, this is the first experimental evidence for sex-specific effects of carotenoid consumption on the immune system of a species with carotenoid-based sexual coloration. These results are consistent with the hypothesis that the mate preference for carotenoid coloration is maintained by the benefits to females of choosing healthy mates, but they cast doubt on the idea that the benefits of carotenoid consumption, per se, could account for the origin of the preference. The sex-specificity of carotenoid effects on allograft rejection in guppies provides indirect support for the general hypothesis that males pay an immunological cost for sexual ornamentation. PMID:15002770

  8. Sex-specific Immune Modulation of Primary Hypertension

    PubMed Central

    Sandberg, Kathryn; Ji, Hong; Hay, Meredith

    2015-01-01

    It is well known that the onset of essential hypertension occurs earlier in men than women. Numerous studies have shown sex differences in the vasculature, kidney and sympathetic nervous system contribute to this sex difference in the development of hypertension. The immune system also contributes to the development of hypertension; however, sex differences in immune system modulation of blood pressure (BP) and the development of hypertension has only recently begun to be explored. Here we review findings on the effect of one's sex on the immune system and specifically how these effects impact BP and the development of primary hypertension. We also propose a hypothesis for why mechanisms underlying inflammation-induced hypertension are sex-specific. These studies underscore the value of and need for studying both sexes in the basic science exploration of the pathophysiology of hypertension as well as other diseases. PMID:25498375

  9. Sex-specific effects of androgen and estrogen on proliferation of the embryonic chicken hypothalamic neurons.

    PubMed

    Cao, Ailing; Zhang, Caiqiao

    2007-04-01

    Effects of androgen and estrogen on proliferation of hypothalamic neurons were evaluated by a chicken hypothalamic neuron-glia coculture model. Hypothalamic cells were dispersed from 17-day-old embryos and challenged with testosterone (T) and 17beta-estradiol (E2) alone or combined with androgen receptor antagonist flutamide, estrogen receptor antagonist tamoxifen, or aromatase inhibitor letrozole for 48 h. The neuron number was counted and the proliferating cells were identified by immunocytochemistry of proliferating cell nuclear antigen (PCNA) and 5-bromo-2-deoxyuridine (BrdU) incorporation. Results showed that both E2 and T stimulated proliferation of hypothalamic neurons. E2 showed more intensive effect on females and this promoting effect was abrogated by tamoxifen. T played more intensive effect on males and the effect was inhibited by flutamide, tamoxifen, or letrozole. The above results indicated that E2 stimulated neuron proliferation through estrogenic actions with more sensitive effect on females and T promoted neuron proliferation through both androgenic and estrogenic actions with more intense effect on males. These observations suggested that steroid hormones influence the proliferation of hypothalamic neurons in a sexually dimorphic manner during the development of chicken embryos. PMID:17873328

  10. Sex-specific prenatal stress effects on the rat reproductive axis and adrenal gland structure.

    PubMed

    Ashworth, Cheryl J; George, Susan O; Hogg, Charis O; Lai, Yu-Ting; Brunton, Paula J

    2016-06-01

    Social stress during pregnancy has profound effects on offspring physiology. This study examined whether an ethologically relevant social stress during late pregnancy in rats alters the reproductive axis and adrenal gland structure in post-pubertal male and female offspring. Prenatally stressed (PNS) pregnant rats (n=9) were exposed to an unfamiliar lactating rat for 10 min/day from day 16 to 20 of pregnancy inclusive, whereas control pregnant rats (n=9) remained in their home cages. Gonads, adrenal glands and blood samples were obtained from one female and one male from each litter at 11 to 12-weeks of age. Anogenital distance was measured. There was no treatment effect on body, adrenal or gonad weight at 11-12 weeks. PNS did not affect the number of primordial, secondary or tertiary ovarian follicles, numbers of corpora lutea or ovarian FSH receptor expression. There was an indication that PNS females had more primary follicles and greater ovarian aromatase expression compared with control females (both P=0.09). PNS males had longer anogenital distances (0.01±0.0 cm/g vs 0.008±0.00 cm/g; P=0.007) and higher plasma FSH concentrations (0.05 ng/mL vs 0.006 ng/mL; s.e.d.=0.023; P=0.043) compared with control males. There were no treatment effects on the number of Sertoli cells or seminiferous tubules, seminiferous tubule area, plasma testosterone concentration or testis expression of aromatase, FSH receptor or androgen receptor. PNS did not affect adrenal size. These data suggest that the developing male reproductive axis is more sensitive to maternal stress and that PNS may enhance aspects of male reproductive development. PMID:27026714

  11. Sex-Specific Effects of Cigarette Mentholation on Brain Nicotine Accumulation and Smoking Behavior

    PubMed Central

    Zuo, Yantao; Mukhin, Alexey G; Garg, Sudha; Nazih, Rachid; Behm, Frederique M; Garg, Pradeep K; Rose, Jed E

    2015-01-01

    Menthol cigarettes are likely associated with greater risks of smoking dependence than non-menthol cigarettes. We sought to test the hypothesis that menthol increases the rate of brain nicotine accumulation (BNA) during smoking and thereby enhances its addictive effects. In a counter-balanced cross-over design, 10 menthol and 9 non-menthol smokers (10 females and 9 males; mean age 44.3) underwent two study phases. In each phase, the participant smoked exclusively either menthol or non-menthol research cigarettes for approximately 1 week prior to a positron emission tomography (PET) scan session, during which the subject's head was scanned following inhalation of a single puff of smoke from a cigarette containing 11C-nicotine. No differences in initial slope, Cmax, area under curve (AUC), and T1/2 of BNA were found between menthol and non-menthol cigarettes across all subjects; however, menthol relative to non-menthol cigarettes were associated with steeper initial slopes in men (p=0.008). Unexpectedly, women had faster BNA as indicated by greater values of the initial slope, Cmax, AUC, and shorter T1/2 than men (all ps<0.04). The rates of BNA were significantly correlated with ratings of smoking motivations of getting a ‘rush', getting relaxing effects and marginally with alleviation of craving. These results do not provide strong support for the putative role of menthol in enhancing BNA, although further studies should explore the apparent effect of menthol on BNA in men. Fast BNA during smoking and preference of sensory properties of menthol cigarettes may independently or jointly contribute to smoking dependence among women. PMID:25267342

  12. Longitudinal pattern of early maturation on morning cortisol and depressive symptoms: Sex-specific effects.

    PubMed

    Sun, Ying; Liu, Yang; Yan, Shuang-Qin; Hu, Jing-Jing; Xu, Geng; Liu, Jiang; Tao, Fang-Biao

    2016-09-01

    There is still insufficient understanding of the underlying processes that contribute to internalizing problems of early maturing adolescents. The purpose of this study is to examine the longitudinal pattern of early maturation and its effects on morning cortisol and depressive symptoms among a general population of adolescent cohort aged 8-11 years old at baseline (boys=424, girls=288). Results suggest newly-onset early maturation boys have 3-times more likely to have depressive symptoms at 1-year follow-up (adjusted odds ratio=3.197, 95% confidence interval=1.595-6.405); while in girls, stable early maturation individuals are more than 4 times as likely to have depressive symptoms (adjusted odds ratio=4.566, 95% confidence interval=1.882-11.077). Morning cortisol has moderating effects in the association of depressive symptoms with newly-onset early maturation in boys and stable early maturation in girls. These findings possibly explain current inconsistent results regarding association between earlier maturation and risk of depression in adolescents. Further longitudinal studies are needed to explore HPG-HPA interactions in adolescence, which may be critical to understanding the heightened susceptibility of mental health problems. PMID:27236487

  13. Prenatal famine exposure has sex-specific effects on brain size.

    PubMed

    de Rooij, Susanne R; Caan, Matthan W A; Swaab, Dick F; Nederveen, Aart J; Majoie, Charles B; Schwab, Matthias; Painter, Rebecca C; Roseboom, Tessa J

    2016-08-01

    Early nutritional deprivation might cause irreversible damage to the brain. Prenatal exposure to undernutrition has been shown to be associated with increased central nervous system anomalies at birth and decreased cognitive function in adulthood. Little is known about the potential effect on the brain in older age. We investigated brain size and structure at age 68 years after prenatal famine exposure. T1-weighted structural magnetic resonance images of the brain were made in 118 Dutch famine birth cohort members. Of these 118 (44% male, age range 65-69 years), 41 had been exposed to famine in early gestation and 77 had been prenatally unexposed. Structural volumes were automatically assessed using FreeSurfer. Diffusion tensor imaging was performed and anisotropy and diffusivity were computed. Fluid attenuated inversion recovery was performed to assess white matter hyperintensities. Exposure to famine in early gestation was associated with smaller intracranial volume in males, but not females. Volumes of total brain, grey and white matter were also smaller in early exposed males, but these differences disappeared after adjusting for intracranial volume. Prenatally exposed males but not females, had a smaller intracranial and total brain volume compared to unexposed subjects. Our findings show that prenatal undernutrition permanently affected brain size.media-1vid110.1093/brain/aww132_video_abstractaww132_video_abstract. PMID:27401522

  14. 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

  15. Effects of timing, sex, and age on site-specific gastrointestinal permeability testing in children and adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Measurement of gastrointestinal permeability is commonly used in research and often used clinically. Despite its utility, little is known about sugar excretion timeframes or the potential effects of age and sex on GI permeability testing. We seek to determine the timeframes of sugar excretion and th...

  16. Sex-specific effects of prenatal chronic mild stress on adult spatial learning capacity and regional glutamate receptor expression profiles.

    PubMed

    Wang, Yan; Ma, Yuchao; Hu, Jingmin; Zhang, Xinxin; Cheng, Wenwen; Jiang, Han; Li, Min; Ren, Jintao; Zhang, Xiaosong; Liu, Mengxi; Sun, Anji; Wang, Qi; Li, Xiaobai

    2016-07-01

    Both animal experiments and clinical studies have demonstrated that prenatal stress can cause cognitive disorders in offspring. To explore the scope of these deficits and identify potential underlying mechanisms, we examined the spatial learning and memory performance and glutamate receptor (GluR) expression patterns of adult rats exposed to prenatal chronic mild stress (PCMS). Principal component analysis (PCA) was employed to reveal the interrelationships among spatial learning indices and GluR expression changes. Female PCMS-exposed offspring exhibited markedly impaired spatial learning and memory in the Morris water maze (MWM) task compared to control females, while PCMS-exposed males showed better initial spatial learning in the MWM compared to control males. PCMS also altered basal and post-MWM glutamate receptor expression patterns, but these effects differed markedly between sexes. Male PCMS-exposed offspring exhibited elevated basal expression of NR1, mGluR5, and mGluR2/3 in the prefrontal cortex (PFC), whereas females showed no basal expression changes. Following MWM training, PCMS-exposed males expressed higher NR1 in the PFC and mammillary body (MB), higher mGluR2/3 in PFC, and lower NR2B in the hippocampus (HIP), PFC, and MB compared to unstressed MWM-trained males. Female PCMS-exposed offspring showed strongly reduced NR1 in MB and NR2B in the HIP, PFC, and MB, and increased mGluR2/3 in PFC compared to unstressed MWM-trained females. This is the first report suggesting that NMDA subunits in the MB are involved in spatial learning. Additionally, PCA further suggests that the NR1-NR2B form is the most important for spatial memory formation. These results reveal long-term sex-specific effects of PCMS on spatial learning and memory performance in adulthood and implicate GluR expression changes within HIP, PFC, and MB as possible molecular mechanisms underlying cognitive dysfunction in offspring exposed to prenatal stress. PMID:27094122

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

    PubMed

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

    2013-05-01

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

  18. Sex-specific effects of social networks on the prevalence, awareness, and control of hypertension among older Korean adults

    PubMed Central

    Baek, Jiwon; Hur, Nam Wook; Kim, Hyeon Chang; Youm, Yoosik

    2016-01-01

    Background Hypertension is a common chronic disease among older adults, and is associated with medical complications and mortality. This study aimed to examine the effects of social network characteristics on the prevalence, awareness, and control of hypertension among older adults. Methods The Korean Social Life, Health, and Aging Project (KSHAP) interviewed 814 ≥ 60-year-old residents and their spouses from a rural township between December 2011 and March 2012 (response rate: 95%). We evaluated the data from 595 participants. Multivariate logistic regression models were used to assess the effects of network characteristics on hypertension. Results We observed strong sex-specific network effects on the prevalence, awareness, and control of hypertension. Among older women, network density was associated with hypertension awareness [odds ratio (OR): 2.63, 95% confidence interval (CI): 1.03–5.37] and control (OR: 1.72; 95% CI: 0.94–3.13). Among older men, large networks were associated with a lower prevalence of hypertension (OR: 0.75; 95% CI: 0.58–0.96). Compared to older women, older men with coarse networks exhibited better hypertension awareness (OR: 0.37; 95% CI: 0.14–0.95) and control (OR: 0.42; 95% CI: 0.19–0.91). Network size interacted with density for hypertension control (P = 0.051), with controlled hypertension being associated with large and course networks. Conclusions A large network was associated with a lower risk for hypertension, and a coarse network was associated with hypertension awareness and control among older men. Older women with dense networks were most likely to exhibit hypertension awareness and control. PMID:27605938

  19. Sex-specific effects of N-acetylcysteine in neonatal rats treated with hypothermia after severe hypoxia-ischemia.

    PubMed

    Nie, Xingju; Lowe, Danielle W; Rollins, Laura Grace; Bentzley, Jessica; Fraser, Jamie L; Martin, Renee; Singh, Inderjit; Jenkins, Dorothea

    2016-07-01

    Approximately half of moderate to severely hypoxic-ischemic (HI) newborns do not respond to hypothermia, the only proven neuroprotective treatment. N-acetylcysteine (NAC), an antioxidant and glutathione precursor, shows promise for neuroprotection in combination with hypothermia, mitigating post-HI neuroinflammation due to oxidative stress. As mechanisms of HI injury and cell death differ in males and females, sex differences must be considered in translational research of neuroprotection. We assessed the potential toxicity and efficacy of NAC in combination with hypothermia, in male and female neonatal rats after severe HI injury. NAC 50mg/kg/d administered 1h after initiation of hypothermia significantly decreased iNOS expression and caspase 3 activation in the injured hemisphere versus hypothermia alone. However, only females treated with hypothermia +NAC 50mg/kg showed improvement in short-term infarct volumes compared with saline treated animals. Hypothermia alone had no effect in this severe model. When NAC was continued for 6 weeks, significant improvement in long-term neuromotor outcomes over hypothermia treatment alone was observed, controlling for sex. Antioxidants may provide insufficient neuroprotection after HI for neonatal males in the short term, while long-term therapy may benefit both sexes. PMID:26851769

  20. Effect of genistein on basal jejunal chloride secretion in R117H CF mice is sex and route specific

    PubMed Central

    Rayyan, Esa; Polito, Sarah; Leung, Lana; Bhakta, Ashesh; Kang, Jonathan; Willey, Justin; Mansour, Wasim; Drumm, Mitchell L; Al-Nakkash, Layla

    2015-01-01

    Cystic fibrosis (CF) results from the loss or reduction in function of the CFTR (cystic fibrosis transmembrane conductance regulatory protein) chloride channel. The third most common CFTR mutation seen clinically is R117H. Genistein, a naturally occurring phytoestrogen, is known to stimulate CFTR function in vitro. We aimed to determine whether route of administration of genistein could mediate differential effects in R117H male and female CF mice. Mice were fed (4 weeks) or injected subcutaneously (1 week) with the following: genistein 600 mg/kg diet (600Gd); genistein-free diet (0Gd); genistein injection 600 mg/kg body weight (600Gi); dimethyl sulfoxide control (0Gi). In male R117H mice fed 600Gd, basal short circuit current (Isc) was unchanged. In 600Gd-fed female mice, there was a subgroup that demonstrated a significant increase in basal Isc (53.14±7.92 μA/cm2, n=6, P<0.05) and a subgroup of nonresponders (12.05±6.59 μA/cm2, n=4), compared to 0Gd controls (29.3±6.5 μA/cm2, n=7). In R117H mice injected with 600Gi, basal Isc was unchanged in both male and female mice compared to 0Gi controls. Isc was measured in response to the following: the adenylate cyclase activator forskolin (10 μM, bilateral), bumetanide (100 μM, basolateral) to indicate the Cl− secretory component, and acetazolamide (100 μM, bilateral) to indicate the HCO3− secretory component; however, there was no effect of genistein (diet or injection) on any of these parameters. Jejunal morphology (ie, villi length, number of goblet cells per villus, crypt depth, and number of goblet cells per crypt) in R117H mice suggested no genistein-mediated difference among the groups. Serum levels of genistein were significantly elevated, compared to respective controls, by either 600Gd (equally elevated in males and females) or 600Gi (elevated more in females versus males). These data suggest a sex-dependent increase in basal Isc of R117H mice and that the increase is also specific for route of

  1. Local mechanisms in sex specific morphogenesis.

    PubMed

    Drews, U

    2000-01-01

    Sex determination in mammals occurs on three levels. Segregation of sex chromosomes determines the chromosomal sex. Sry on the Y chromosome induces formation of a testis which in turn regulates via AMH and testosterone the development of the genital tract and the external phenotype. Recently a number of new factors have been described, which affect sexual development but have not yet found a place in the above canonical scheme of sex determination. For the purpose of this review, the factors are aligned according to their quality as transcription factors, steroid hormones, or growth factors. In this web of regulatory factors, the classical sex determining factors have evolved as master mechanisms while others function as slaves, or were totally suppressed. In this context, androgens acquired a dominant role in mammalian development. Androgens determine the morphogenesis of the genital tract. The effects of androgens are mediated by local cellular interactions. In the cranial section of the Wolffian duct the androgen receptor appears in the epithelium and mediates maintenance of the duct via an epithelial factor. In the caudal section of the duct the androgen receptor is expressed in the embryonic mesenchyme. Vesicular glands are induced via a morphogenetically active mesenchymal condensation, while the epithelial buds are primarily AR androgen receptor negative. The dominant role of androgens and formation of a vagina evolved together at the transition to eutherian mammals. Under this aspect, the role of androgens in the development of the vagina is analyzed. PMID:11173834

  2. Sex-specific effects of an avian malaria parasite on an insect vector: support for the resource limitation hypothesis.

    PubMed

    Waite, Jessica L; Henry, Autumn R; Adler, Frederick R; Clayton, Dale H

    2012-11-01

    Many parasites, such as those that cause malaria, depend on an insect vector for transmission between vertebrate hosts. Theory predicts that parasites should have little or no effect on the transmission ability of vectors, e.g., parasites should not reduce vector life span as this will limit the temporal window of opportunity for transmission. However, if the parasite and vector compete for limited resources, there may be an unavoidable physiological cost to the vector (resource limitation hypothesis). If this cost reduces vector fitness, then the effect should be on reproduction, not survival. Moreover, in cases where both sexes act as vectors, the effect should be greater on females than males because of the greater cost of reproduction for females. We tested these predictions using Haemoproteus columbae, a malaria parasite of Rock Pigeons (Columba livia) that is vectored by both sexes of the hippoboscid fly Pseudolynchia canariensis, Hippoboscids belong to a group of insects (Hippoboscoidea) with unusually high female reproductive investment; eggs hatch in utero, and each larva progresses through three stages, feeding from internal "milk" glands in the female, followed by deposition as a large puparium. We compared fitness components for flies feeding on malaria-infected vs. uninfected Rock Pigeons. Survival of female flies decreased significantly when they fed on infected birds, while survival of male flies was unaffected. Our results were contrary to the overall prediction that malaria parasites should have no effect on vector survival, but consistent with the prediction that an effect, if present, would be greater on females. As predicted, females feeding on malaria-infected birds produced fewer offspring, but there was no effect on the quality of offspring. A separate short-term feeding experiment confirmed that female flies are unable to compensate for resource limitation by altering blood meal size. The unanticipated effect on female survival may be

  3. Pre-learning stress that is temporally removed from acquisition exerts sex-specific effects on long-term memory.

    PubMed

    Zoladz, Phillip R; Warnecke, Ashlee J; Woelke, Sarah A; Burke, Hanna M; Frigo, Rachael M; Pisansky, Julia M; Lyle, Sarah M; Talbot, Jeffery N

    2013-02-01

    We have examined the influence of sex and the perceived emotional nature of learned information on pre-learning stress-induced alterations of long-term memory. Participants submerged their dominant hand in ice cold (stress) or warm (no stress) water for 3 min. Thirty minutes later, they studied 30 words, rated the words for their levels of emotional valence and arousal and were then given an immediate free recall test. Twenty-four hours later, participants' memory for the word list was assessed via delayed free recall and recognition assessments. The resulting memory data were analyzed after categorizing the studied words (i.e., distributing them to "positive-arousing", "positive-non-arousing", "negative-arousing", etc. categories) according to participants' valence and arousal ratings of the words. The results revealed that participants exhibiting a robust cortisol response to stress exhibited significantly impaired recognition memory for neutral words. More interestingly, however, males displaying a robust cortisol response to stress demonstrated significantly impaired recall, overall, and a marginally significant impairment of overall recognition memory, while females exhibiting a blunted cortisol response to stress demonstrated a marginally significant impairment of overall recognition memory. These findings support the notion that a brief stressor that is temporally separated from learning can exert deleterious effects on long-term memory. However, they also suggest that such effects depend on the sex of the organism, the emotional salience of the learned information and the degree to which stress increases corticosteroid levels. PMID:23266791

  4. Sex-specific determinants of fitness in a social mammal.

    PubMed

    Lardy, Sophie; Allainé, Dominique; Bonenfant, Christophe; Cohas, Aurélie

    2015-11-01

    Sociality should evolve when the fitness benefits of group living outweigh the costs. Theoretical models predict an optimal group size maximizing individual fitness. However, beyond the number of individuals present in a group, the characteristics of these individuals, like their sex, are likely to affect the fitness payoffs of group living. Using 20 years of individually based data on a social mammal, the Alpine marmot (Marmota marmota), we tested for the occurrence of an optimal group size and composition, and for sex-specific effects of group characteristics on fitness. Based on lifetime data of 52 males and 39 females, our findings support the existence of an optimal group size maximizing male fitness and an optimal group composition maximizing fitness of males and females. Additionally, although group characteristics (i.e., size, composition and instability) affecting male and female fitness differed, fitness depended strongly on the number of same-sex subordinates within the social group in the two sexes. By comparing multiple measures of social group characteristics and of fitness in both sexes, we highlighted the sex-specific determinants of fitness in the two sexes and revealed the crucial role of intrasexual competition in shaping social group composition. PMID:27070014

  5. Sex-specific urinary biomarkers for diagnosing bipolar disorder.

    PubMed

    Chen, Jian-jun; Huang, Hua; Zhao, Li-bo; Zhou, De-zhi; Yang, Yong-tao; Zheng, Peng; Yang, De-yu; He, Peng; Zhou, Jing-jing; Fang, Liang; Xie, Peng

    2014-01-01

    Sex-based differences are prominent in affective disorders, but there are no biomarkers available to support sex-specific, laboratory-based diagnostics for male and female bipolar disorder (BD) patients. Here, a NMR-based metabonomic approach was used to preliminarily identify sex-specific urinary metabolite biomarkers for diagnosing male and female BD patients. A male-specific biomarker panel consisting of four metabolites (α-hydroxybutyrate, choline, formate, and N-methylnicotinamide) effectively discriminated between male BD and healthy controls (HC) subjects, achieving an area under the receiver operating characteristic curve (AUC) of 0.942. A female-specific biomarkers panel consisting of four metabolites (α-hydroxybutyrate, oxalacetate, acetone, and N-methylnicotinamide) effectively discriminated between female BD and HC subjects, achieving an AUC of 0.909. The male-specific biomarker panel displayed low discriminatory power in the female group, and the female-specific biomarker panel displayed low discriminatory power in the male group. Moreover, several other metabolites showed different trends between male and female BD subjects. These findings suggest that male and female BD patients have distinct biomarker fingerprints and that these two sex-specific biomarker panels may serve as effective diagnostic tools in distinguishing male and female BD patients from their healthy counterparts. Our work may provide a window into the mechanisms underlying the pathoetiology of BD in both men and women. PMID:25531985

  6. 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. PMID:27547321

  7. Early-life lead exposure results in dose- and sex-specific effects on weight and epigenetic gene regulation in weanling mice

    PubMed Central

    Faulk, Christopher; Barks, Amanda; Liu, Kevin; Goodrich, Jaclyn M; Dolinoy, Dana C

    2013-01-01

    Aims Epidemiological and animal data suggest that the development of adult chronic conditions is influenced by early-life exposure-induced changes to the epigenome. This study investigates the effects of perinatal lead (Pb) exposure on DNA methylation and bodyweight in weanling mice. Materials & methods Viable yellow agouti (Avy) mouse dams were exposed to 0, 2.1, 16 and 32 ppm Pb acetate before conception through weaning. Epigenetic effects were evaluated by scoring coat color of Avy/a offspring and quantitative bisulfite sequencing of two retrotransposon-driven (Avy and CDK5 activator-binding protein intracisternal A particle element) and two imprinted (Igf2 and Igf2r) loci in tail DNA. Results Maternal blood Pb levels were below the limit of detection in controls, and 4.1, 25.1 and 32.1 μg/dl for each dose, respectively. Pb exposure was associated with a trend of increased wean bodyweight in males (p = 0.03) and altered coat color in Avy/a offspring. DNA methylation at Avy and the CDK5 activator-binding protein intracisternal A-particle element was significantly different from controls following a cubic trend (p = 0.04; p = 0.01), with male-specific effects at the Avy locus. Imprinted genes did not shift in methylation across exposures. Conclusion Dose- and sex-specific responses in bodyweight and DNA methylation indicate that Pb acts on the epigenome in a locus-specific fashion, dependent on the genomic feature hosting the CpG site of interest, and that sex is a factor in epigenetic response. PMID:24059796

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

    PubMed Central

    Gear, Robin B.; Kendig, Eric L.

    2015-01-01

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

  9. Effects of Timing, Sex, and Age on Site-Specific Gastrointestinal Permeability Testing in Children and Adults

    PubMed Central

    McOmber, Mark E.; Ou, Ching-Nan; Shulman, Robert J.

    2010-01-01

    Summary Objectives Measurement of gastrointestinal (GI) permeability is used commonly in research and often clinically. Despite its utility, little is known about sugar excretion timeframes or the potential effects of age and gender in GI permeability testing. We sought to determine the timeframes of sugar excretion and the potential effects of age and gender on urinary recovery of the sugars. Methods Healthy adults (n=17) and children (n=15) fasted four hours after the evening meal and then ingested a solution of sucrose, lactulose, mannitol, and sucralose. Urine was collected at 30, 60, and 90 minutes after ingestion and then each time the subjects voided over the next 24 hr. Each urine void was collected separately. Results Median age for the adults was 47.5 yr. (range 21-57 yr.) and for children 10 yr. (5-17). There were no differences between children and adults in mean percent dose of sugar recovered. The time of peak urinary recovery of the sugars was generally similar between children and adults. Sucrose urinary recovery declined with age (P = 0.008; r2 = 0.19) unrelated to gender. Lactulose and sucralose urinary recovery declined with age in females (P = 0.05, r2 = 0.24 and P = 0.011, r2 = 0.41, respectively) but not in males. Conclusions Overall, sugar urinary recovery is comparable in children and adults. Specific sugar urinary recovery may change as a function of age and/or gender. These results need to be taken into account when planning and interpreting GI permeability studies. PMID:20081547

  10. Sex-specific pruning of neuronal synapses in Caenorhabditis elegans.

    PubMed

    Oren-Suissa, Meital; Bayer, Emily A; Hobert, Oliver

    2016-05-12

    Whether and how neurons that are present in both sexes of the same species can differentiate in a sexually dimorphic manner is not well understood. A comparison of the connectomes of the Caenorhabditis elegans hermaphrodite and male nervous systems reveals the existence of sexually dimorphic synaptic connections between neurons present in both sexes. Here we demonstrate sex-specific functions of these sex-shared neurons and show that many neurons initially form synapses in a hybrid manner in both the male and hermaphrodite pattern before sexual maturation. Sex-specific synapse pruning then results in the sex-specific maintenance of subsets of these connections. Reversal of the sexual identity of either the pre- or postsynaptic neuron alone transforms the patterns of synaptic connectivity to that of the opposite sex. A dimorphically expressed and phylogenetically conserved transcription factor is both necessary and sufficient to determine sex-specific connectivity patterns. Our studies reveal new insights into sex-specific circuit development. PMID:27144354

  11. Sex-specific and time-dependent effects of prenatal stress on the early behavioral symptoms of ADHD: a longitudinal study in China.

    PubMed

    Zhu, Peng; Hao, Jia-Hu; Tao, Rui-Xue; Huang, Kun; Jiang, Xiao-Min; Zhu, Yuan-Duo; Tao, Fang-Biao

    2015-09-01

    There is increasing evidence that prenatal stressful life events (SLEs) may be a potential risk factor for attention-deficit hyperactivity disorder (ADHD), but the sex-specific and time-dependent effects of prenatal stress on ADHD are less clear. In this prospective longitudinal study, data on prenatal SLEs during different stages of gestation and indicators of buffers against stress, including maternal social support and avoidance coping, were obtained from 1765 pregnant women at 32 weeks of gestation. The behavioral symptoms of ADHD in children aged 48-54 months were evaluated by reports from the parents. There were 226 children (12.8%) above the clinically significant cutoff for ADHD. After adjusting for potential confounders, boys whose mother experienced severe SLEs in the second trimester had a significantly increased risk (OR = 2.41, 95% CI: 1.03-5.66) of developing ADHD symptoms compared with boys whose mothers did not experience severe SLEs at this time. However, no significantly increased risk of ADHD symptoms was observed in girls born to mothers experienced prenatal severe SLEs. Additionally, significant interaction effects of prenatal SLEs, social support and coping style on ADHD symptoms were found in males. Boys whose mothers experienced severe SLEs during the second trimester accompanied by a higher score for avoidance coping (OR = 3.31, 95% CI: 1.13-9.70) or a lower score for social support (OR = 4.39, 95% CI: 1.05-18.31) were likely to be at a higher risk for ADHD symptoms. The epidemiological evidence in this prospective follow-up study suggests that the effect of prenatal SLEs on ADHD symptoms in offspring may depend on the timing of prenatal stress and may vary according to the sex of the offspring. PMID:25791080

  12. Using RAD-seq to recognize sex-specific markers and sex chromosome systems.

    PubMed

    Gamble, Tony

    2016-05-01

    Next-generation sequencing methods have initiated a revolution in molecular ecology and evolution (Tautz et al. ). Among the most impressive of these sequencing innovations is restriction site-associated DNA sequencing or RAD-seq (Baird et al. ; Andrews et al. ). RAD-seq uses the Illumina sequencing platform to sequence fragments of DNA cut by a specific restriction enzyme and can generate tens of thousands of molecular genetic markers for analysis. One of the many uses of RAD-seq data has been to identify sex-specific genetic markers, markers found in one sex but not the other (Baxter et al. ; Gamble & Zarkower ). Sex-specific markers are a powerful tool for biologists. At their most basic, they can be used to identify the sex of an individual via PCR. This is useful in cases where a species lacks obvious sexual dimorphism at some or all life history stages. For example, such tests have been important for studying sex differences in life history (Sheldon ; Mossman & Waser ), the management and breeding of endangered species (Taberlet et al. ; Griffiths & Tiwari ; Robertson et al. ) and sexing embryonic material (Hacker et al. ; Smith et al. ). Furthermore, sex-specific markers allow recognition of the sex chromosome system in cases where standard cytogenetic methods fail (Charlesworth & Mank ; Gamble & Zarkower ). Thus, species with male-specific markers have male heterogamety (XY) while species with female-specific markers have female heterogamety (ZW). In this issue, Fowler & Buonaccorsi () illustrate the ease by which RAD-seq data can generate sex-specific genetic markers in rockfish (Sebastes). Moreover, by examining RAD-seq data from two closely related rockfish species, Sebastes chrysomelas and Sebastes carnatus (Fig. ), Fowler & Buonaccorsi () uncover shared sex-specific markers and a conserved sex chromosome system. PMID:27213697

  13. 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. PMID:27365446

  14. Neurosteroids and their role in sex-specific epilepsies.

    PubMed

    Reddy, Doodipala Samba

    2014-12-01

    Neurosteroids are involved in sex-specific epilepsies. Allopregnanolone and related endogenous neurosteroids in the brain control excessive neuronal excitability and seizure susceptibility. Neurosteroids activate GABA-A receptors, especially extrasynaptic αγδ-GABA-A receptor subtypes that mediate tonic inhibition and thus dampen network excitability. Our studies over the past decade have shown that neurosteroids are broad-spectrum anticonvulsants and confer seizure protection in various animal models. Neurosteroids also exert antiepileptogenic effects. There is emerging evidence on a critical role for neurosteroids in the pathophysiology of the sex-specific forms of epilepsies such as catamenial epilepsy, a menstrual cycle-related seizure disorder in women. Catamenial epilepsy is a neuroendocrine condition in which seizures are clustered around specific points in the menstrual cycle, most often around the perimenstrual or periovulatory period. Apart from ovarian hormones, fluctuations in neurosteroid levels could play a critical role in this gender-specific epilepsy. Neurosteroids also regulate the plasticity of synaptic and extrasynaptic GABA-A receptors in the hippocampus and other regions involved in epilepsy pathology. Based on these studies, we proposed a neurosteroid replacement therapy for catamenial epilepsy. Thus, neurosteroids are novel drug targets for pharmacotherapy of epilepsy. PMID:24960208

  15. Smoking modulates language lateralization in a sex-specific way.

    PubMed

    Hahn, Constanze; Pogun, Sakire; Güntürkün, Onur

    2010-12-01

    Smoking affects a widespread network of neuronal functions by altering the properties of acetylcholinergic transmission. Recent studies show that nicotine consumption affects ascending auditory pathways and alters auditory attention, particularly in men. Here we show that smoking affects language lateralization in a sex-specific way. We assessed brain asymmetries of 90 healthy, right-handed participants using a classic consonant-vowel syllable dichotic listening paradigm in a 2×3 experimental design with sex (male, female) and smoking status (non-smoker, light smoker, heavy smoker) as between-subject factors. Our results revealed that male smokers had a significantly less lateralized response pattern compared to the other groups due to a decreased response rate of their right ear. This finding suggests a group-specific impairment of the speech dominant left hemisphere. In addition, decreased overall response accuracy was observed in male smokers compared to the other experimental groups. Similar adverse effects of smoking were not detected in women. Further, a significant negative correlation was detected between the severity of nicotine dependency and response accuracy in male but not in female smokers. Taken together, these results show that smoking modulates functional brain lateralization significantly and in a sexually dimorphic manner. Given that some psychiatric disorders have been associated with altered brain asymmetries and increased smoking prevalence, nicotinergic effects need to be specifically investigated in this context in future studies. PMID:20951712

  16. Part II: Strain- and sex-specific effects of adolescent exposure to THC on adult brain and behaviour: Variants of learning, anxiety and volumetric estimates.

    PubMed

    Keeley, R J; Trow, J; Bye, C; McDonald, R J

    2015-07-15

    Marijuana is one of the most highly used psychoactive substances in the world, and its use typically begins during adolescence, a period of substantial brain development. Females across species appear to be more susceptible to the long-term consequences of marijuana use. Despite the identification of inherent differences between rat strains including measures of anatomy, genetics and behaviour, no studies to our knowledge have examined the long-term consequences of adolescent exposure to marijuana or its main psychoactive component, Δ(9)-tetrahydrocannabinol (THC), in males and females of two widely used rat strains: Long-Evans hooded (LER) and Wistar (WR) rats. THC was administered for 14 consecutive days following puberty onset, and once they reached adulthood, changes in behaviour and in the volume of associated brain areas were quantified. Rats were assessed in behavioural tests of motor, spatial and contextual learning, and anxiety. Some tasks showed effects of injection, since handled and vehicle groups were included as controls. Performance on all tasks, except motor learning, and the volume of associated brain areas were altered with injection or THC administration, although these effects varied by strain and sex group. Finally, analysis revealed treatment-specific correlations between performance and brain volumes. This study is the first of its kind to directly compare males and females of two rat strains for the long-term consequences of adolescent THC exposure. It highlights the importance of considering strain and identifies certain rat strains as susceptible or resilient to the effects of THC. PMID:25591471

  17. Sex-specific effects of inbreeding in wild-caught Drosophila melanogaster under benign and stressful conditions.

    PubMed

    Enders, L S; Nunney, L

    2010-11-01

    In animal populations, sib mating is often the primary source of inbreeding depression (ID). We used recently wild-caught Drosophila melanogaster to test whether such ID is amplified by environmental stress and, in males, by sexual selection. We also investigated whether increased ID because of stress (increased larval competition) persisted beyond the stressed stage and whether the effects of stress and sexual selection interacted. Sib mating resulted in substantial cumulative fitness losses (egg to adult reproduction) of 50% (benign) and 73% (stressed). Stress increased ID during the larval period (23% vs. 63%), but not during post-stress reproductive stages (36% vs. 31%), indicating larval stress may have purged some adult genetic load (although ID was uncorrelated across stages). Sexual selection exacerbated inbreeding depression, with inbred male offspring suffering a higher reproductive cost than females, independent of stress (57% vs. 14% benign, 49% vs. 11% stress). PMID:20874846

  18. Sex-Specific Content Preferences for Visual Sexual Stimuli

    PubMed Central

    Rupp, Heather A.; Wallen, Kim

    2009-01-01

    Although experimental studies support that men generally respond more to visual sexual stimuli than do women, there is substantial variability in this effect. One potential source of variability is the type of stimuli used that may not be of equal interest to both men and women whose preferences may be dependent upon the activities and situations depicted. The current study investigated whether men and women had preferences for certain types of stimuli. We measured the subjective evaluations and viewing times of 15 men and 30 women (15 using hormonal contraception) to sexually explicit photos. Heterosexual participants viewed 216 pictures that were controlled for the sexual activity depicted, gaze of the female actor, and the proportion of the image that the genital region occupied. Men and women did not differ in their overall interest in the stimuli, indicated by equal subjective ratings and viewing times, although there were preferences for specific types of pictures. Pictures of the opposite sex receiving oral sex were rated as least sexually attractive by all participants and they looked longer at pictures showing the female actor’s body. Women rated pictures in which the female actor was looking indirectly at the camera as more attractive, while men did not discriminate by female gaze. Participants did not look as long at close-ups of genitals, and men and women on oral contraceptives rated genital images as less sexually attractive. Together, these data demonstrate sex-specific preferences for specific types of stimuli even when, across stimuli, overall interest was comparable. PMID:18719987

  19. Sex-Specific Differences in Lipid and Glucose Metabolism

    PubMed Central

    Varlamov, Oleg; Bethea, Cynthia L.; Roberts, Charles T.

    2014-01-01

    Energy metabolism in humans is tuned to distinct sex-specific functions that potentially reflect the unique requirements in females for gestation and lactation, whereas male metabolism may represent a default state. These differences are the consequence of the action of sex chromosomes and sex-specific hormones, including estrogens and progesterone in females and androgens in males. In humans, sex-specific specialization is associated with distinct body-fat distribution and energy substrate-utilization patterns; i.e., females store more lipids and have higher whole-body insulin sensitivity than males, while males tend to oxidize more lipids than females. These patterns are influenced by the menstrual phase in females, and by nutritional status and exercise intensity in both sexes. This minireview focuses on sex-specific mechanisms in lipid and glucose metabolism and their regulation by sex hormones, with a primary emphasis on studies in humans and the most relevant pre-clinical model of human physiology, non-human primates. PMID:25646091

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

    PubMed

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

    2015-08-01

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

  1. Teacher Expressiveness: Effects of Teacher Sex and Student Sex.

    ERIC Educational Resources Information Center

    Basow, Susan A.

    Student ratings of college professors play an important role in many employment decisions. One factor strongly associated with student ratings is teacher expressiveness. A study was conducted to explore the effects of teacher expressiveness, teacher sex, and student sex on student ratings of their instructor, student perceptions of their…

  2. Reducing Risky Sex Among College Students: Prospects for Context-Specific Interventions.

    PubMed

    Mair, Christina; Ponicki, William R; Gruenewald, Paul J

    2016-01-01

    Better understanding the contribution of specific drinking contexts to alcohol use and risky sexual behaviors can help target effective prevention programs to specific locations and types of drinkers. We used a sample of college students to investigate whether more frequent and heavier drinking in specific drinking contexts was associated with unplanned sex, unprotected sex, and number of sexual contacts. Greater frequencies of drinking in almost all contexts (Greek parties, off-campus parties, campus events, dorms, and bars) were associated with greater numbers of sexual partners, unplanned sex and unprotected sex; heavier drinking at bars increased risks related to all outcomes. Risks related to frequencies of use of contexts were similar for men and women, but heavier drinking at bars was associated with more unprotected sex among males only. We discuss these observations in light of their implications for developing context-specific interventions to reduce community viral load in high-risk populations. PMID:26238039

  3. Sex-Specific Mediating Role of Insulin Resistance and Inflammation in the Effect of Adiposity on Blood Pressure of Prepubertal Children

    PubMed Central

    Correia-Costa, Liane; Santos, Ana Cristina; Severo, Milton; Guerra, António; Schaefer, Franz; Caldas Afonso, Alberto; Barros, Henrique; Azevedo, Ana

    2015-01-01

    Objective To evaluate the association between obesity indices and blood pressure (BP) at 4 years of age, in each sex, and to quantify to which extent this association is mediated by inflammation and insulin resistance (IR). Materials and Methods We studied 1250 4-year-old children selected from the population-based birth cohort Generation XXI. Associations between body mass index (BMI) z-score and waist-to-height ratio (WHtR), office BP, inflammation (high sensitivity C-reactive protein) and IR (HOMA-IR index) were assessed. Path Analysis, a modified multivariate regression approach, was applied to test causal models and quantify direct and indirect effects of predictors of systolic (SBP) and diastolic BP (DBP). Results SBP and DBP increased significantly with BMI and WHtR in both sexes. There was a strong direct association (explaining 74.1-93.2% of the total association) of both measures of adiposity with SBP, in both sexes. This association was additionally indirectly mediated by IR, particularly regarding WHtR (20.5% in girls and 9.4% in boys). Mediation by inflammation did not reach statistical significance in either sex. Regarding DBP, the direct effect of adiposity was strong (>95% for BMI and WHtR in boys) and the mediation by IR was much smaller in boys than in girls. Discussion The direct association between adiposity and BP in healthy 4-year-old children is strong and IR plays an important mediating role. The strength of effects of IR and inflammation suggests sex differences in the complex interplay between BP, adiposity and inflammation. PMID:26125190

  4. Sex Specification and Heterogeneity of Primordial Germ Cells in Mice

    PubMed Central

    Sakashita, Akihiko; Kawabata, Yukiko; Jincho, Yuko; Tajima, Shiun; Kumamoto, Soichiro; Kobayashi, Hisato; Matsui, Yasuhisa; Kono, Tomohiro

    2015-01-01

    In mice, primordial germ cells migrate into the genital ridges by embryonic day 13.5 (E13.5), where they are then subjected to a sex-specific fate with female and male primordial germ cells undergoing mitotic arrest and meiosis, respectively. However, the sex-specific basis of primordial germ cell differentiation is poorly understood. The aim of this study was to investigate the sex-specific features of mouse primordial germ cells. We performed RNA-sequencing (seq) of E13.5 female and male mouse primordial germ cells using next-generation sequencing. We identified 651 and 428 differentially expressed transcripts (>2-fold, P < 0.05) in female and male primordial germ cells, respectively. Of these, many transcription factors were identified. Gene ontology and network analysis revealed differing functions of the identified female- and male-specific genes that were associated with primordial germ cell acquisition of sex-specific properties required for differentiation into germ cells. Furthermore, DNA methylation and ChIP-seq analysis of histone modifications showed that hypomethylated gene promoter regions were bound with H3K4me3 and H3K27me3. Our global transcriptome data showed that in mice, primordial germ cells are decisively assigned to a sex-specific differentiation program by E13.5, which is necessary for the development of vital germ cells. PMID:26700643

  5. Sex-specific prediction of neck muscle volumes

    PubMed Central

    Zheng, Liying; Siegmund, Gunter; Ozyigit, Gulsum; Vasavada, Anita

    2013-01-01

    Biomechanical analyses of the head and neck system require knowledge of neck muscle forces, which are often estimated from neck muscle volumes. Here we use magnetic resonance images (MRIs) of 17 subjects (6 females, 11 males) to develop a method to predict the volumes of 16 neck muscles by first predicting the total neck muscle volume (TMV) from subject sex and anthropometry, and then predicting individual neck muscle volumes using fixed volume proportions for each neck muscle. We hypothesized that the regression equations for total muscle volume as well as individual muscle volume proportions would be sex specific. We found that females have 59% lower TMV compared to males (females: 510±43 cm3, males: 814±64 cm3; p<0.0001) and that TMV (in cm3) was best predicted by a regression equation that included sex (male=0, female=1) and neck circumference (NC, in cm): TMV=269+13.7NC−233 Sex (adjusted R2=0.868; p<0.01). Individual muscle volume proportions were not sex specific for most neck muscles, although small sex differences existed for three neck muscles (obliqus capitis inferior, longus capitis, and sternocleidomastoid). When predicting individual muscle volumes in subjects not used to develop the model, coefficients of concordance ranged from 0.91 to 0.99. This method of predicting individual neck muscle volumes has the advantage of using only one sex-specific regression equation and one set of sex-specific volume proportions. These data can be used in biomechanical models to estimate muscle forces and tissue loads in the cervical spine. PMID:23351366

  6. 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

  7. Tissue Specificity and Sex-Specific Regulatory Variation Permit the Evolution of Sex-Biased Gene Expression.

    PubMed

    Dean, Rebecca; Mank, Judith E

    2016-09-01

    Genetic correlations between males and females are often thought to constrain the evolution of sexual dimorphism. However, sexually dimorphic traits and the underlying sexually dimorphic gene expression patterns are often rapidly evolving. We explore this apparent paradox by measuring the genetic correlation in gene expression between males and females (Cmf) across broad evolutionary timescales, using two RNA-sequencing data sets spanning multiple populations and multiple species. We find that unbiased genes have higher Cmf than sex-biased genes, consistent with intersexual genetic correlations constraining the evolution of sexual dimorphism. However, we found that highly sex-biased genes (both male and female biased) also had higher tissue specificity, and unbiased genes had greater expression breadth, suggesting that pleiotropy may constrain the breakdown of intersexual genetic correlations. Finally, we show that genes with high Cmf showed some degree of sex-specific changes in gene expression in males and females. Together, our results suggest that genetic correlations between males and females may be less important in constraining the evolution of sex-biased gene expression than pleiotropy. Sex-specific regulatory variation and tissue specificity may resolve the paradox of widespread sex bias within a largely shared genome. PMID:27501094

  8. Sex-Specific Genomic Biomarkers for Individualized Treatment of Life-Threatening Diseases

    PubMed Central

    Moon, Hojin; Lopez, Karen L.; Lin, Grace I.; Chen, James J.

    2013-01-01

    Numerous studies have demonstrated sex differences in drug reactions to the same drug treatment, steering away from the traditional view of one-size-fits-all medicine. A premise of this study is that the sex of a patient influences difference in disease characteristics and risk factors. In this study, we intend to exploit and to obtain better sex-specific biomarkers from gene-expression data. We propose a procedure to isolate a set of important genes as sex-specific genomic biomarkers, which may enable more effective patient treatment. A set of sex-specific genes is obtained by a variable importance ranking using a combination of cross-validation methods. The proposed procedure is applied to three gene-expression datasets. PMID:24302811

  9. Sex-specific adaptation drives early sex chromosome evolution in Drosophila.

    PubMed

    Zhou, Qi; Bachtrog, Doris

    2012-07-20

    Most species' sex chromosomes are derived from ancient autosomes and show few signatures of their origins. We studied the sex chromosomes of Drosophila miranda, where a neo-Y chromosome originated only approximately 1 million years ago. Whole-genome and transcriptome analysis reveals massive degeneration of the neo-Y, that male-beneficial genes on the neo-Y are more likely to undergo accelerated protein evolution, and that neo-Y genes evolve biased expression toward male-specific tissues--the shrinking gene content of the neo-Y becomes masculinized. In contrast, although older X chromosomes show a paucity of genes expressed in male tissues, neo-X genes highly expressed in male-specific tissues undergo increased rates of protein evolution if haploid in males. Thus, the response to sex-specific selection can shift at different stages of X differentiation, resulting in masculinization or demasculinization of the X-chromosomal gene content. PMID:22822149

  10. Quantitative trait loci with sex-specific effects for internal organs weights and hematocrit value in a broiler-layer cross.

    PubMed

    Moura, A S A M T; Ledur, M C; Boschiero, C; Nones, K; Pinto, L F B; Jaenisch, F R F; Burt, D W; Coutinho, L L

    2016-05-01

    Rapid growth in broilers is associated with susceptibility to metabolic disorders such as pulmonary hypertension syndrome (ascites) and sudden death. This study describes a genome search for QTL associated with relative weight of cardio respiratory and metabolically important organs (heart, lungs, liver and gizzard), and hematocrit value in a Brazilian broiler-layer cross. QTL with similar or different effects across sexes were investigated. At 42 days of age after fasted for 6 h, the F2 chickens were weighed and slaughtered. Weights and percentages of the weight relative to BW42 of gizzard, heart, lungs, liver and hematocrit were used in the QTL search. Parental, F1 and F2 individuals were genotyped with 128 genetic markers (127 microsatellites and 1 SNP) covering 22 linkage groups. QTL mapping analyses were carried out using mixed models. A total of 11 genome-wide significant QTL and five suggestive linkages were mapped. Thus, genome-wide significant QTL with similar effects across sexes were mapped to GGA2, 4 and 14 for heart weight, and to GGA2, 8 and 12 for gizzard %. Additionally, five genome-wide significant QTL with different effects across sexes were mapped to GGA 8, 19 and 26 for heart weight; GGA26 for heart % and GGA3 for hematocrit value. Five QTL were detected in chromosomal regions where QTL for similar traits were previously mapped in other F2 chicken populations. Seven novel genome-wide significant QTL are reported here, and 21 positional candidate genes in QTL regions were identified. PMID:26496990

  11. Infant sex-specific placental cadmium and DNA methylation associations

    SciTech Connect

    Mohanty, April F.; Farin, Fred M.; Bammler, Theo K.; MacDonald, James W.; Afsharinejad, Zahra; Burbacher, Thomas M.; Siscovick, David S.; and others

    2015-04-15

    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. 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

  12. Sex-Specific Mechanism of Social Hierarchy in Mice

    PubMed Central

    van den Berg, Wouter E; Lamballais, Sander; Kushner, Steven A

    2015-01-01

    The establishment of social hierarchies is a naturally occurring, evolutionarily conserved phenomenon with a well-established impact on fitness and health. Investigations of complex social group dynamics may offer novel opportunities for translational studies of autism spectrum disorder. Here we describe a robust behavioral paradigm using an automated version of the tube test. Isogenic groups of male and female mice establish linear social hierarchies that remain highly stable for at least 14 days, the longest interval tested. Remarkably, however, their social strategy is sex-specific: females primarily utilize intrinsic attributes, whereas males are strongly influenced by prior social experience. Using both genetic and pharmacological manipulations, we identify testosterone as a critical sex-specific factor for determining which social strategy is used. Males inheriting a null mutation of the sex-determining region Y (Sry) gene used a similar social cognitive strategy as females. In contrast, females with transgenic expression of Sry utilized a typically male social strategy. Analogously, castration of males and testosterone supplementation of females yielded similar outcomes, with a reversal of their social cognitive strategy. Together, our results demonstrate a sex-specific mechanism underlying social hierarchy, in which both males and females retain the functional capacity to adapt their social strategy. More generally, we expect the automated tube test to provide an important complementary approach for both fundamental and translational studies of social behavior. PMID:25469681

  13. Passive limb movement: evidence of mechanoreflex sex specificity

    PubMed Central

    McDaniel, John; Witman, Melissa A. H.; Richardson, Russell S.

    2013-01-01

    Previous studies have determined that premenopausal women exhibit an attenuated metaboreflex; however, little is known about sex specificity of the mechanoreflex. Thus, we sought to determine if sex differences exist in the central and peripheral hemodynamic responses to passive limb movement. Second-by-second measurements of heart rate, stroke volume, cardiac output (CO), mean arterial pressure, and femoral artery blood flow (FBF) were recorded during 3 min of supine passive knee extension in 24 young healthy subjects (12 women and 12 men). Normalization of CO and stroke volume to body surface area, expressed as cardiac index and stroke index, eliminated differences in baseline central hemodynamics, whereas, peripherally, basal FBF and femoral vascular conductance were similar between the sexes. In response to passive limb movement, women displayed significantly attenuated peak central hemodynamic responses compared with men (heart rate: 9.0 ± 1 vs. 14.8 ± 2% change, stroke index: 4.5 ± 0.6 vs. 7.8 ± 1.2% change, cardiac index: 9.6 ± 1 vs. 17.2 ± 2% change, all P < 0.05), whereas movement induced similar increases in peak FBF (167 ± 32 vs. 193 ± 17% change) and femoral vascular conductance (172 ± 31 vs. 203 ± 16% change) in both sexes (women vs. men, respectively). Additionally, there was a significant positive relationship between individual peak FBF and peak CO response to passive movement in men but not in women. Thus, although both sexes exhibited similar movement-induced hyperemia and peripheral vasodilatory function, the central hemodynamic response was blunted in women, implying an attenuated mechanoreflex. Therefore, this study reveals that, as already recognized with the metaboreflex, there is likely a sex-specific attenuation of the mechanoreflex in women. PMID:23086995

  14. Estimators of the Human Effective Sex Ratio Detect Sex Biases on Different Timescales

    PubMed Central

    Emery, Leslie S.; Felsenstein, Joseph; Akey, Joshua M.

    2010-01-01

    Determining historical sex ratios throughout human evolution can provide insight into patterns of genomic variation, the structure and composition of ancient populations, and the cultural factors that influence the sex ratio (e.g., sex-specific migration rates). Although numerous studies have suggested that unequal sex ratios have existed in human evolutionary history, a coherent picture of sex-biased processes has yet to emerge. For example, two recent studies compared human X chromosome to autosomal variation to make inferences about historical sex ratios but reached seemingly contradictory conclusions, with one study finding evidence for a male bias and the other study identifying a female bias. Here, we show that a large part of this discrepancy can be explained by methodological differences. Specifically, through reanalysis of empirical data, derivation of explicit analytical formulae, and extensive simulations we demonstrate that two estimators of the effective sex ratio based on population structure and nucleotide diversity preferentially detect biases that have occurred on different timescales. Our results clarify apparently contradictory evidence on the role of sex-biased processes in human evolutionary history and show that extant patterns of human genomic variation are consistent with both a recent male bias and an earlier, persistent female bias. PMID:21109223

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

    PubMed

    Kramer, Maxwell; Rao, Prashant; Ercan, Sevinc

    2016-09-01

    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

  16. Sex-specific mediation effect of the right fusiform face area volume on the association between variants in repeat length of AVPR1A RS3 and altruistic behavior in healthy adults.

    PubMed

    Wang, Junping; Qin, Wen; Liu, Feng; Liu, Bing; Zhou, Yuan; Jiang, Tianzi; Yu, Chunshui

    2016-07-01

    Microsatellite variants in the arginine vasopressin receptor 1A gene (AVPR1A) RS3 have been associated with normal social behaviors variation and autism spectrum disorders (ASDs) in a sex-specific manner. However, neural mechanisms underlying these associations remain largely unknown. We hypothesized that AVPR1A RS3 variants affect altruistic behavior by modulating the gray matter volume (GMV) of specific brain regions in a sex-specific manner. We investigated 278 young healthy adults using the Dictator Game to assess altruistic behavior. All subjects were genotyped and main effect of AVPR1A RS3 repeat polymorphisms and interaction of genotype-by-sex on the GMV were assessed in a voxel-wise manner. We observed that male subjects with relatively short repeats allocated less money to others and exhibited a significantly smaller GMV in the right fusiform face area (FFA) compared with male long homozygotes. In male subjects, the GMV of the right FFA exhibited a significant positive correlation with altruistic behavior. A mixed mediation and moderation analysis further revealed both a significant mediation effect of the GMV of the right FFA on the association between AVPR1A RS3 repeat polymorphisms and allocation sums and a significant moderation effect of sex (only in males) on the mediation effect. Post hoc analysis showed that the GMV of the right FFA was significantly smaller in male subjects carrying allele 426 than in non-426 carriers. These results suggest that the GMV of the right FFA may be a potential mediator whereby the genetic variants in AVPR1A RS3 affect altruistic behavior in healthy male subjects. Hum Brain Mapp 37:2700-2709, 2016. © 2016 Wiley Periodicals, Inc. PMID:27027249

  17. Sex-specific variability and a 'cage effect' independently mask a neuropathic pain quantitative trait locus detected in a whole genome scan.

    PubMed

    Devor, Marshall; Gilad, Amit; Arbilly, Michal; Nissenbaum, Jonathan; Yakir, Benjamin; Raber, Pnina; Minert, Anne; Pisanté, Anne; Darvasi, Ariel

    2007-08-01

    Sex and environment may dramatically affect genetic studies, and thus should be carefully considered. Beginning with two inbred mouse strains with contrasting phenotype in the neuroma model of neuropathic pain (autotomy), we established a backcross population on which we conducted a genome-wide scan. The backcross population was partially maintained in small social groups and partially in isolation. The genome scan detected one previously reported quantitative trait locus (QTL) on chromosome 15 (pain1), but no additional QTLs were found. Interestingly, group caging introduced phenotypic noise large enough to completely mask the genetic effect of the chromosome 15 QTL. The reason appears to be that group-caging animals from the low-autotomy strain together with animals from the high-autotomy strain dramatically increases autotomy in the otherwise low-autotomy mice (males or females). The converse, suppression of pain behaviour in the high-autotomy strain when caged with the low-autotomy strain was also observed, but only in females. Even in isolated mice, the genetic effect of the chromosome 15 QTL was significant only in females. To determine why, we evaluated autotomy levels of females in 12 different inbred stains of mice and compared them to previously reported levels for males. Strikingly larger environmental variation was observed in males than in females for this pain phenotype. The high baseline variance in males can explain the difficulty in detecting the genetic effect, which was readily seen in females. Our study emphasizes the importance of sex and environment in the genetic analysis of pain. PMID:17686043

  18. Sex-Specific Placental Responses in Fetal Development

    PubMed Central

    2015-01-01

    The placenta is an ephemeral but critical organ for the survival of all eutherian mammals and marsupials. It is the primary messenger system between the mother and fetus, where communicational signals, nutrients, waste, gases, and extrinsic factors are exchanged. Although the placenta may buffer the fetus from various environmental insults, placental dysfunction might also contribute to detrimental developmental origins of adult health and disease effects. The placenta of one sex over the other might possess greater ability to respond and buffer against environmental insults. Given the potential role of the placenta in effecting the lifetime health of the offspring, it is not surprising that there has been a resurging interest in this organ, including the Human Placental Project launched by the National Institutes of Child Health and Human Development. In this review, we will compare embryological development of the laboratory mouse and human chorioallantoic placentae. Next, evidence that various species, including humans, exhibit normal sex-dependent structural and functional placental differences will be examined followed by how in utero environmental changes (nutritional state, stress, and exposure to environmental chemicals) might interact with fetal sex to affect this organ. Recent data also suggest that paternal state impacts placental function in a sex-dependent manner. The research to date linking placental maladaptive responses and later developmental origins of adult health and disease effects will be explored. Finally, we will focus on how sex chromosomes and epimutations may contribute to sex-dependent differences in placental function, the unanswered questions, and future directions that warrant further consideration. PMID:26241064

  19. Sex-Specific Placental Responses in Fetal Development.

    PubMed

    Rosenfeld, Cheryl S

    2015-10-01

    The placenta is an ephemeral but critical organ for the survival of all eutherian mammals and marsupials. It is the primary messenger system between the mother and fetus, where communicational signals, nutrients, waste, gases, and extrinsic factors are exchanged. Although the placenta may buffer the fetus from various environmental insults, placental dysfunction might also contribute to detrimental developmental origins of adult health and disease effects. The placenta of one sex over the other might possess greater ability to respond and buffer against environmental insults. Given the potential role of the placenta in effecting the lifetime health of the offspring, it is not surprising that there has been a resurging interest in this organ, including the Human Placental Project launched by the National Institutes of Child Health and Human Development. In this review, we will compare embryological development of the laboratory mouse and human chorioallantoic placentae. Next, evidence that various species, including humans, exhibit normal sex-dependent structural and functional placental differences will be examined followed by how in utero environmental changes (nutritional state, stress, and exposure to environmental chemicals) might interact with fetal sex to affect this organ. Recent data also suggest that paternal state impacts placental function in a sex-dependent manner. The research to date linking placental maladaptive responses and later developmental origins of adult health and disease effects will be explored. Finally, we will focus on how sex chromosomes and epimutations may contribute to sex-dependent differences in placental function, the unanswered questions, and future directions that warrant further consideration. PMID:26241064

  20. SEX-SPECIFIC ENVIRONMENTAL INFLUENCES ON THE DEVELOPMENT OF AUTOIMMUNE DISEASES

    PubMed Central

    Tiniakou, Eleni; Costenbader, Karen H.; Kriegel, Martin A.

    2013-01-01

    Sex differences in autoimmune diseases are evolutionarily tied to the fact that the female immune system is confronted with intense alterations during menstrual cycles, pregnancy and childbirth. These events may be associated with breaches in the mucosal epithelial layers that are shielding us from environmental factors. Associations between environmental agents and autoimmune diseases have been described extensively in prior studies. Little evidence, however, exists for sex-specific environmental effects on autoimmune diseases. In this review, we summarize studies involving this often-neglected aspect. We give examples of environmental factors that may influence the sex bias in autoimmunity. We conclude that most studies do not give insight into sex-specific environmental effects due to the influence of gender-selective social, occupational or other exposures. Prospective studies are needed in order to determine true sex-biased environmental influences. Finally, humanized murine models might aid in better understanding the mechanisms involved in sex-specific environmental effects on autoimmune diseases. PMID:23507400

  1. Sex-specific predictors of suicidality among runaway youth.

    PubMed

    Leslie, Michelle Burden; Stein, Judith A; Rotheram-Borus, Mary Jane

    2002-03-01

    Examined predictors of suicidality (ideation and attempts) among 348 adolescent runways (197 boys; 56% African American; M age = 16) using sex-specific models that tested the impact of the three domains of the Social Action Model: individual characteristics, interpersonal influences, and life events. Twenty-five percent of the girls and 14% of the boys had attempted suicide at least once. Male suicidality was mainly predicted by individual characteristics: identifying as gay, emotional distress, fewer conduct problems, and avoidant reasons for drug use. The interpersonal influence of suicidal friends also predicted suicidality. Variables from all three domains influenced girls: individual characteristics of lower age, lower self-esteem, and emotional distress; interpersonal influence of suicidal friends; and life events of having lived on the streets and assaults. Findings suggest some sex-specific interventions, but decreasing emotional distress and lessening the influence of suicidal friends may be useful for both boys and girls. PMID:11845647

  2. Sex-specific regulation of Lgr3 in Drosophila neurons

    PubMed Central

    Meissner, Geoffrey W.; Luo, Shengzhan D.; Dias, Brian G.; Texada, Michael J.; Baker, Bruce S.

    2016-01-01

    The development of sexually dimorphic morphology and the potential for sexually dimorphic behavior in Drosophila are regulated by the Fruitless (Fru) and Doublesex (Dsx) transcription factors. Several direct targets of Dsx have been identified, but direct Fru targets have not been definitively identified. We show that Drosophila leucine-rich repeat G protein-coupled receptor 3 (Lgr3) is regulated by Fru and Dsx in separate populations of neurons. Lgr3 is a member of the relaxin-receptor family and a receptor for Dilp8, necessary for control of organ growth. Lgr3 expression in the anterior central brain of males is inhibited by the B isoform of Fru, whose DNA binding domain interacts with a short region of an Lgr3 intron. Fru A and C isoform mutants had no observed effect on Lgr3 expression. The female form of Dsx (DsxF) separately up- and down-regulates Lgr3 expression in distinct neurons in the abdominal ganglion through female- and male-specific Lgr3 enhancers. Excitation of neural activity in the DsxF–up-regulated abdominal ganglion neurons inhibits female receptivity, indicating the importance of these neurons for sexual behavior. Coordinated regulation of Lgr3 by Fru and Dsx marks a point of convergence of the two branches of the sex-determination hierarchy. PMID:26884206

  3. Sex effects on inflammatory and neurodegenerative processes in multiple sclerosis.

    PubMed

    Ramien, Caren; Taenzer, Aline; Lupu, Andreea; Heckmann, Nina; Engler, Jan Broder; Patas, Kostas; Friese, Manuel A; Gold, Stefan M

    2016-08-01

    Clinical observations in human autoimmune diseases such as multiple sclerosis (MS) suggest a pivotal role of sex-related factors in the etiopathogenesis. These include a female preponderance in MS incidence and an increasing sex bias over time, a parent-of-origin effect in MS inheritance, and the protective effect of pregnancy on disease activity. The complex interplay of factors contributing to these clinical phenomena, however, is incompletely understood and may include sex hormones as well as genetic or epigenetic sex differences. While genetic and hormonal effects are impossible to study independently in humans, novel mouse models have started to unravel the cause-effect relationship between individual sex-related factors and autoimmunity. Here, we present the evidence for mechanisms underlying sex differences in the immune system and the central nervous system (CNS) and how these might help to explain some of the clinically observed sex differences in MS. A better understanding of the molecular underpinnings may ultimately help to devise sex-specific treatment strategies as well as highlight novel avenues for therapy in both sexes. PMID:26773723

  4. Toward Sex-Specific Guidelines for Cardiac Resynchronization Therapy?

    PubMed

    Zusterzeel, Robbert; Selzman, Kimberly A; Sanders, William E; O'Callaghan, Kathryn M; Caños, Daniel A; Vernooy, Kevin; Prinzen, Frits W; Gorgels, Anton P M; Strauss, David G

    2016-02-01

    An important treatment for patients with heart failure is cardiac resynchronization therapy (CRT). Even though only 20% of women were included in clinical trials for CRT, a benefit has been shown in recent studies for subgroups of women compared to their male counterparts. Given this low inclusion rate of women in clinical studies, professional society guideline-based CRT recommendations, such as those by the American College of Cardiology Foundation (ACCF)/American Heart Association (AHA)/Heart Rhythm Society (HRS), may not truly represent the best treatment for women, especially since most of the reports that showed this greater benefit in women were published after the latest guidelines. Despite having research and multiple publications regarding sex-specific heart failure outcomes and response to CRT, the ACCF/AHA/HRS guidelines have not yet been updated to account for the recent information regarding the differences in benefit for women and men with similar patient characteristics. This review discusses the physiology behind CRT, sex-specific characteristics of heart failure, and cardiac electrophysiology and summarizes the current sex-specific literature to encourage consideration of CRT guidelines for women and men separately. PMID:26659647

  5. Sex-specific, counteracting responses to inbreeding in a bird.

    PubMed Central

    Pizzari, Tommaso; Løvlie, Hanne; Cornwallis, Charles K.

    2004-01-01

    Inbreeding often depresses offspring fitness. Because females invest more than males in a reproductive event, inbreeding is expected to be more costly to mothers than fathers, creating a divergence between the reproductive interests of each sex and promoting sex-specific inbreeding strategies. Males and females may bias the probability of inbreeding by selecting copulation partners, and, in sexually promiscuous species, through male strategic sperm investment in different females and female selection of the sperm of different males. However, these processes are often difficult to study, and the way that different male and female strategies interact to determine inbreeding remains poorly understood. Here we demonstrate sex-specific, counteracting responses to inbreeding in the promiscuous red junglefowl, Gallus gallus. First, a male was just as likely to copulate with his full-sib sister as with an unrelated female. In addition, males displayed a tendency to: (i) initiate copulation faster when exposed to an unrelated female than when exposed to a sister, and (ii) inseminate more sperm into sisters than into unrelated females. Second, females retained fewer sperm following insemination by brothers, thus reducing the risk of inbreeding and counteracting male inbreeding strategies. PMID:15475330

  6. Sex-specific, counteracting responses to inbreeding in a bird.

    PubMed

    Pizzari, Tommaso; Løvlie, Hanne; Cornwallis, Charles K

    2004-10-22

    Inbreeding often depresses offspring fitness. Because females invest more than males in a reproductive event, inbreeding is expected to be more costly to mothers than fathers, creating a divergence between the reproductive interests of each sex and promoting sex-specific inbreeding strategies. Males and females may bias the probability of inbreeding by selecting copulation partners, and, in sexually promiscuous species, through male strategic sperm investment in different females and female selection of the sperm of different males. However, these processes are often difficult to study, and the way that different male and female strategies interact to determine inbreeding remains poorly understood. Here we demonstrate sex-specific, counteracting responses to inbreeding in the promiscuous red junglefowl, Gallus gallus. First, a male was just as likely to copulate with his full-sib sister as with an unrelated female. In addition, males displayed a tendency to: (i) initiate copulation faster when exposed to an unrelated female than when exposed to a sister, and (ii) inseminate more sperm into sisters than into unrelated females. Second, females retained fewer sperm following insemination by brothers, thus reducing the risk of inbreeding and counteracting male inbreeding strategies. PMID:15475330

  7. [Sex Specificity in Age-Related Thyroid Hormone Responsiveness].

    PubMed

    Suzuki, Satoru

    2016-01-01

    Similar to other systems, the endocrine system is affected by aging. Thyroid hormone, the action of which is affected by many factors, has been shown to be associated with longevity. The most useful marker for assessment of the thyroid hormone action is the TSH level. Although age and sex are believed to modify the pituitary set point or response to the free thyroid hormone concentration, the precise age- and sex-dependent responses to thyroid hormone have yet to be reported. In this lecture, molecular aspects of resistance to thyroid hormone are initially overviewed. After presentation of the evidence that the TSH-thyroid hormone axis is evolutionarily modified, and that negative feedback mechanisms may start to play roles in homeostatic regulation at the time of delivery, the rationale of age-dependent thyroid hormone resistance is introduced. To assess the age- and sex-dependent resistance to thyroid hormone, the index is provided by the formula based on the relationship between thyroid hormone and TSH levels. The index is calculated by the results of thyroid function tests obtained from the two individual clinical groups. From the results, there were negative relationships between the free T3 resistance index and age in males of both groups, while there were no apparent relationships in females. These findings indicate that there is a male-specific response to thyroid hormone with aging. Furthermore, the specific features of the response may not be affected by environmental factors such as the presence of disorders or medical treatments. PMID:27192800

  8. Sex-specific adaptation drives early sex chromosome evolution in Drosophila

    PubMed Central

    Zhou, Qi; Bachtrog, Doris

    2014-01-01

    Most species’ sex chromosomes are derived from ancient autosomes and show few signatures of their origins. We studied the sex chromosomes of Drosophila miranda, where a neo-Y chromosome originated only about 1 million years (MY) ago. Whole genome and transcriptome analysis reveals massive degeneration of the neo-Y, that male-beneficial genes on the neo-Y are more likely to undergo accelerated protein-evolution, and that neo-Y genes evolve biased expression towards male-specific tissues, i.e. the shrinking gene content of the neo-Y becomes masculinized. In contrast, while older X chromosomes show a paucity of genes expressed in male tissues, neo-X genes highly expressed in male-specific tissues undergo increased rates of protein evolution if haploid in males. Thus, the response to sex-specific selection can shift at different stages of X differentiation, resulting in masculinization or demasculinization of the X-chromosomal gene content. PMID:22822149

  9. Sex-Specific Issues in Inflammatory Bowel Disease.

    PubMed

    Rosenblatt, Elizabeth; Kane, Sunanda

    2015-09-01

    Inflammatory bowel disease (IBD) affects approximately 1 in 500 people living in the United States and generally occurs with equal frequency in men and women. However, despite equal sex distribution of the disease, men and women face unique challenges that can significantly impact quality of life. As more is discovered regarding the pathogenesis, clinical manifestations, and treatment of IBD, physiologic and psychological differences between men and women with IBD have become increasingly apparent. It is important to understand these differences, as they have the potential to affect patient care and outcomes. This article will review sex-specific issues in IBD, such as impaired body image and sexuality, increased risk of cervical cancer, altered menstrual cycles, reduced fertility, and low bone mineral density. PMID:27482181

  10. Sex-Specific Issues in Inflammatory Bowel Disease

    PubMed Central

    Rosenblatt, Elizabeth

    2015-01-01

    Inflammatory bowel disease (IBD) affects approximately 1 in 500 people living in the United States and generally occurs with equal frequency in men and women. However, despite equal sex distribution of the disease, men and women face unique challenges that can significantly impact quality of life. As more is discovered regarding the pathogenesis, clinical manifestations, and treatment of IBD, physiologic and psychological differences between men and women with IBD have become increasingly apparent. It is important to understand these differences, as they have the potential to affect patient care and outcomes. This article will review sex-specific issues in IBD, such as impaired body image and sexuality, increased risk of cervical cancer, altered menstrual cycles, reduced fertility, and low bone mineral density. PMID:27482181

  11. Metabolomics reveals the sex-specific effects of the SORT1 low-density lipoprotein cholesterol locus in healthy young adults.

    PubMed

    Klein, Matthias S; Connors, Kimberly E; Shearer, Jane; Vogel, Hans J; Hittel, Dustin S

    2014-11-01

    Metabolite profiles of individuals possessing either the cardiovascular risk or protective variants of the low-density lipoprotein cholesterol (LDL-C) associated 1p13.3 locus of the SORT1 gene (rs646776) were analyzed. Serum metabolites and lipids were assessed using LC-MS-based metabolomics in a healthy young population (n = 138: 95 males, 43 females). Although no significant differences were observed in the combined cohort, divergent sex effects were identified. Females carrying the protective allele showed increased phosphatidylcholines, very long chain fatty acids (>C20), and unsaturated fatty acids. Unsaturated fatty acids are considered to be protective against cardiovascular disease. In contrast, males carrying the protective allele exhibited decreased long-chain fatty acids (≤C20) and sphingomyelins, which is similarly considered to decrease cardiovascular disease risk. No significant changes in clinically assessed lipids such as LDL-C, high-density lipoprotein (HDL-C), total cholesterol, or triglycerides were observed in females, whereas only LDL-C was significantly changed in males. This indicates that, apart from reducing LDL-C, other mechanisms may contribute to the protective effect of the SORT1 locus. Thus, the analysis of metabolic biomarkers might reveal early disease development that may be overlooked by relying on standard clinical parameters. PMID:25182463

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

    PubMed

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

    2012-02-01

    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 (E(2)) 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 E(2) 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, E(2), 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 E(2) 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

  13. 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

  14. Effects of partner beauty on opposite-sex attractiveness judgments.

    PubMed

    Little, Anthony C; Caldwell, Christine A; Jones, Benedict C; DeBruine, Lisa M

    2011-12-01

    Many studies show mate choice copying effects on mate preferences in non-human species in which individuals follow or copy the mate choices of same-sex conspecifics. Recent studies suggest that social learning also influences mate preferences in humans. Studies on heterosexual humans have focused on rating the attractiveness of potential mates (targets) presented alongside individuals of the opposite sex to the target (models). Here, we examined several different types of pairing to examine how specific social learning is to mate preferences. In Study 1, we replicated a previous effect whereby target faces of the opposite sex to the subject were rated as more attractive when paired with attractive than unattractive partner models of the same sex as the subject. Using the same paired stimuli, Study 2 demonstrated no effect of a paired model if subjects were asked to rate targets who were the same sex as themselves. In Study 3, we used pairs of the same sex, stating the pair were friends, and subjects rated targets of the opposite sex to themselves. Attractive models decreased targets' attractiveness, opposite to the effect in Study 1. Finally, Study 4 examined if attractive versus unattractive non-face stimuli might influence attraction. Unlike in Study 1, pairing with attractive stimuli either had no effect or decreased the attractiveness of paired target face images. These data suggest that social transmission of preferences via pairing with attractive/unattractive images is relatively specific to learning about mate preferences but does not influence attractiveness judgments more generally. PMID:21901646

  15. Sexual orientation, drug use preference during sex, and HIV risk practices and preferences among men who specifically seek unprotected sex partners via the internet.

    PubMed

    Klein, Hugh

    2009-05-01

    The present study entailed conducting a content analysis of 1,434 ads/profiles posted on one of the most popular "Men who have Sex with Men" (MSM) websites that specifically fosters unprotected sex. Ads/profiles were selected randomly based on the American ZIP code of residence (n = 1,316), with a randomly-drawn oversampling of profiles of men who self-identified as heterosexual or "curious" rather than gay or bisexual (n = 118). Data were collected between September 2006 and September 2007. The purpose of the present paper is to examine the conjoint effects of self-identified sexual orientation and preference for having/not having sex while high, on men's sought-after sexual risk. Analytical comparisons of the four groups showed that, on most measures, the combination of sexual orientation and drug use preference during sex differentiated the men. Generally speaking, gay/bisexual men who advertised online for partners with whom they could have sex while high expressed the greatest interest in risky sexual behaviors (e.g., felching, unprotected oral sex, unprotected anal sex) and various risk-related preferences (e.g., multiple partner sex, anonymous sex, eroticizing ejaculatory fluids). This is especially true when they are compared to their heterosexual/"curious" counterparts whose online profiles were not as likely to indicate a desire for having sex while high. PMID:19543410

  16. Long lasting sex-specific effects upon behavior and S100b levels after maternal separation and exposure to a model of post-traumatic stress disorder in rats.

    PubMed

    Diehl, Luisa Amalia; Silveira, Patrícia Pelufo; Leite, Marina C; Crema, Leonardo Machado; Portella, Andre Krumel; Billodre, Mauro Nör; Nunes, Edelvan; Henriques, Thiago P; Fidelix-da-Silva, Linda Brenda; Heis, Marta D; Gonçalves, Carlos Alberto; Quillfeldt, Jorge Alberto; Dalmaz, Carla

    2007-05-01

    This study was undertaken to verify if repeated long-term separation from dams would affect the development of parameters related to post-traumatic stress disorder (PTSD) after animals are subjected to inescapable shock when adults. Wistar rats were subjected to repeated maternal separation during post-natal days 1-10. When adults, rats from both sexes were submitted to a PTSD model consisting of exposure to inescapable footshock, followed by situational reminders. We observed long-lasting effects of both interventions. Exposure to shock increased fear conditioning. Anxiety-like behavior was increased and exploratory activity decreased by both treatments, and these effects were more robust in males. Additionally, basal corticosterone in plasma was decreased, paralleling effects observed in PTSD patients. Levels of S100B protein in serum and cerebrospinal fluid (CSF) were measured. Levels in serum correlated with the effects observed in anxiety-like behavior, increasing in males exposed to shock, and presenting no effect in females. S100B in CSF was increased in females submitted to maternal separation during the neonatal period. These results suggest that, in rats, an early stress experience such as maternal separation may aggravate some effects of exposure to a stressor during adult age, and that this effect is sex-specific. Additionally, data suggest that the increased S100B levels, observed in serum, have an extracerebral origin, possibly mediated by an increase in the noradrenergic tonus. Increased S100B in brain could be related to its neurotrophic actions. PMID:17335785

  17. Melatonin influences sex-specific prenatal mortality in meadow voles.

    PubMed

    Gorman, M R; Ferkin, M H; Dark, J

    1994-11-01

    Meadow voles exhibit seasonal changes in litter size, ovulation rates, and prenatal mortality. To investigate the proximate bases of seasonal changes in reproductive effort, adult female voles, maintained in long photoperiods (14 h of light/day), were injected daily with 10 micrograms melatonin 2 h before light offset to extend the duration of the nighttime melatonin pulse. At parturition the number, sex, and weight of offspring were assessed. The number of ovarian corpora lutea (CL), an index of potential litter size, was used to calculate rates of prenatal survival (i.e., pups per CL). Prenatal survival rates were reduced in female but not male pups of dams that had been injected before blastocyst implantation (Days 1-6 of pregnancy) with melatonin as compared with saline. Melatonin injections initiated after blastocyst implantation (Days 7-21 of pregnancy) did not affect prenatal survival, nor were birth weights of pups affected by either pre- or postimplantation melatonin treatment. We conclude that sex-specific prenatal survival is a labile feature of vole reproduction that may be under proximate control of photoperiod and melatonin before blastocyst implantation. PMID:7849189

  18. The effect of parasites on sex differences in selection

    PubMed Central

    Sharp, N P; Vincent, C M

    2015-01-01

    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. PMID:25649503

  19. Basal superoxide as a sex-specific immune constraint

    PubMed Central

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

    2011-01-01

    There is increasing evidence that reactive oxygen species (ROS), a group of unstable and highly reactive chemical molecules, play a key role in regulating and maintaining life-history trade-offs. Upregulation of ROS in association with immune activation is costly because it may result in an imbalance between pro- and antioxidants and, hence, oxidative damage. Previous research aimed at quantifying this cost has mostly focused on changes in the pro-/antioxidant balance subsequent to an immune response. Here, we test the hypothesis that systemic ROS may constrain immune activation. We show that systemic, pre-challenge superoxide (SO) levels are negatively related to the strength of the subsequent immune response towards the mitogen phytohaemagglutinin in male, but not female painted dragon lizards (Ctenophorus pictus). We therefore suggest that systemic SO constrains immune activation in painted dragon males. We speculate that this may be due to sex-specific selection pressures on immune investment. PMID:21632618

  20. Basal superoxide as a sex-specific immune constraint.

    PubMed

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

    2011-12-23

    There is increasing evidence that reactive oxygen species (ROS), a group of unstable and highly reactive chemical molecules, play a key role in regulating and maintaining life-history trade-offs. Upregulation of ROS in association with immune activation is costly because it may result in an imbalance between pro- and antioxidants and, hence, oxidative damage. Previous research aimed at quantifying this cost has mostly focused on changes in the pro-/antioxidant balance subsequent to an immune response. Here, we test the hypothesis that systemic ROS may constrain immune activation. We show that systemic, pre-challenge superoxide (SO) levels are negatively related to the strength of the subsequent immune response towards the mitogen phytohaemagglutinin in male, but not female painted dragon lizards (Ctenophorus pictus). We therefore suggest that systemic SO constrains immune activation in painted dragon males. We speculate that this may be due to sex-specific selection pressures on immune investment. PMID:21632618

  1. Sex-specific differences in injury types among basketball players

    PubMed Central

    Ito, Eri; Iwamoto, Jun; Azuma, Koichiro; Matsumoto, Hideo

    2015-01-01

    The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females) were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%), and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%). The proportion of anterior cruciate ligament injury in the 10–19-year-old age group was higher among female players than among male players (45.9% vs 22.1%), while the proportions of Osgood–Schlatter disease in the 10–19-year-old age group and jumper’s knee (patellar and femoral tendinopathy) in the 20–29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively). However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball. PMID:25565908

  2. Sex-specific plasticity and genotype × sex interactions for age and size of maturity in the sheepshead swordtail, Xiphophorus birchmanni.

    PubMed

    Boulton, K; Rosenthal, G G; Grimmer, A J; Walling, C A; Wilson, A J

    2016-03-01

    Responses to sexually antagonistic selection are thought to be constrained by the shared genetic architecture of homologous male and female traits. Accordingly, adaptive sexual dimorphism depends on mechanisms such as genotype-by-sex interaction (G×S) and sex-specific plasticity to alleviate this constraint. We tested these mechanisms in a population of Xiphophorus birchmanni (sheepshead swordtail), where the intensity of male competition is expected to mediate intersexual conflict over age and size at maturity. Combining quantitative genetics with density manipulations and analysis of sex ratio variation, we confirm that maturation traits are dimorphic and heritable, but also subject to large G×S. Although cross-sex genetic correlations are close to zero, suggesting sex-linked genes with important effects on growth and maturation are likely segregating in this population, we found less evidence of sex-specific adaptive plasticity. At high density, there was a weak trend towards later and smaller maturation in both sexes. Effects of sex ratio were stronger and putatively adaptive in males but not in females. Males delay maturation in the presence of mature rivals, resulting in larger adult size with subsequent benefit to competitive ability. However, females also delay maturation in male-biased groups, incurring a loss of reproductive lifespan without apparent benefit. Thus, in highly competitive environments, female fitness may be limited by the lack of sex-specific plasticity. More generally, assuming that selection does act antagonistically on male and female maturation traits in the wild, our results demonstrate that genetic architecture of homologous traits can ease a major constraint on the evolution of adaptive dimorphism. PMID:26688295

  3. Sex-specific selection for MHC variability in Alpine chamois

    PubMed Central

    2012-01-01

    Background In mammals, males typically have shorter lives than females. This difference is thought to be due to behavioural traits which enhance competitive abilities, and hence male reproductive success, but impair survival. Furthermore, in many species males usually show higher parasite burden than females. Consequently, the intensity of selection for genetic factors which reduce susceptibility to pathogens may differ between sexes. High variability at the major histocompatibility complex (MHC) genes is believed to be advantageous for detecting and combating the range of infectious agents present in the environment. Increased heterozygosity at these immune genes is expected to be important for individual longevity. However, whether males in natural populations benefit more from MHC heterozygosity than females has rarely been investigated. We investigated this question in a long-term study of free-living Alpine chamois (Rupicapra rupicapra), a polygynous mountain ungulate. Results Here we show that male chamois survive significantly (P = 0.022) longer if heterozygous at the MHC class II DRB locus, whereas females do not. Improved survival of males was not a result of heterozygote advantage per se, as background heterozygosity (estimated across twelve microsatellite loci) did not change significantly with age. Furthermore, reproductively active males depleted their body fat reserves earlier than females leading to significantly impaired survival rates in this sex (P < 0.008). This sex-difference was even more pronounced in areas affected by scabies, a severe parasitosis, as reproductively active males were less likely to survive than females. However, we did not find evidence for a survival advantage associated with specific MHC alleles in areas affected by scabies. Conclusions Increased MHC class II DRB heterozygosity with age in males, suggests that MHC heterozygous males survive longer than homozygotes. Reproductively active males appear to be less likely to

  4. Sex Differences in Drosophila melanogaster Heterochromatin Are Regulated by Non-Sex Specific Factors

    PubMed Central

    Apte, Manasi S.; Meller, Victoria H.

    2015-01-01

    The eukaryotic genome is assembled into distinct types of chromatin. Gene-rich euchromatin has active chromatin marks, while heterochromatin is gene-poor and enriched for silencing marks. In spite of this, genes native to heterochromatic regions are dependent on their normal environment for full expression. Expression of genes in autosomal heterochromatin is reduced in male flies mutated for the noncoding roX RNAs, but not in females. roX mutations also disrupt silencing of reporter genes in male, but not female, heterochromatin, revealing a sex difference in heterochromatin. We adopted a genetic approach to determine how this difference is regulated, and found no evidence that known X chromosome counting elements, or the sex determination pathway that these control, are involved. This suggested that the sex chromosome karyotype regulates autosomal heterochromatin by a different mechanism. To address this, candidate genes that regulate chromosome organization were examined. In XX flies mutation of Topoisomerase II (Top2), a gene involved in chromatin organization and homolog pairing, made heterochromatic silencing dependent on roX, and thus male-like. Interestingly, Top2 also binds to a large block of pericentromeric satellite repeats (359 bp repeats) that are unique to the X chromosome. Deletion of X heterochromatin also makes autosomal heterochromatin in XX flies dependent on roX and enhances the effect of Top2 mutations, suggesting a combinatorial action. We postulate that Top2 and X heterochromatin in Drosophila comprise a novel karyotype-sensing pathway that determines the sensitivity of autosomal heterochromatin to loss of roX RNA. PMID:26053165

  5. Specificity Determinants of the Silkworm Moth Sex Pheromone

    PubMed Central

    Xu, Pingxi; Hooper, Antony M.; Pickett, John A.; Leal, Walter S.

    2012-01-01

    The insect olfactory system, particularly the peripheral sensory system for sex pheromone reception in male moths, is highly selective, but specificity determinants at the receptor level are hitherto unknown. Using the Xenopus oocyte recording system, we conducted a thorough structure-activity relationship study with the sex pheromone receptor of the silkworm moth, Bombyx mori, BmorOR1. When co-expressed with the obligatory odorant receptor co-receptor (BmorOrco), BmorOR1 responded in a dose-dependent fashion to both bombykol and its related aldehyde, bombykal, but the threshold of the latter was about one order of magnitude higher. Solubilizing these ligands with a pheromone-binding protein (BmorPBP1) did not enhance selectivity. By contrast, both ligands were trapped by BmorPBP1 leading to dramatically reduced responses. The silkworm moth pheromone receptor was highly selective towards the stereochemistry of the conjugated diene, with robust response to the natural (10E,12Z)-isomer and very little or no response to the other three isomers. Shifting the conjugated diene towards the functional group or elongating the carbon chain rendered these molecules completely inactive. In contrast, an analogue shortened by two omega carbons elicited the same or slightly higher responses than bombykol. Flexibility of the saturated C1–C9 moiety is important for function as addition of a double or triple bond in position 4 led to reduced responses. The ligand is hypothesized to be accommodated by a large hydrophobic cavity within the helical bundle of transmembrane domains. PMID:22957053

  6. Effects of Single-Sex Secondary Schools on Student Achievement and Attitudes.

    ERIC Educational Resources Information Center

    Lee, Valerie E.; Bryk, Anthony S.

    1986-01-01

    This study compares the effects of single-sex and coeducational secondary schooling. Results indicate that single-sex schools deliver specific advantages to their students, especially female students. Single-sex schools may facilitate adolescent academic development by providing an environment where social and academic concerns are separated.…

  7. The Effectiveness of the Tupiq Program for Inuit Sex Offenders.

    PubMed

    Stewart, Lynn A; Hamilton, Ellen; Wilton, Geoff; Cousineau, Colette; Varrette, Steven K

    2015-11-01

    This study examines the effectiveness of the Tupiq program, a culturally specific program for Inuit sex offenders that incorporates cognitive behavioural methods with traditional Inuit knowledge and culture led by Inuit healers and facilitators. Outcomes of 61 offenders who participated in the Tupiq program and were released were compared with outcomes of a cohort of 114 released Inuit sex offenders incarcerated during the same time period who had taken alternative sex offender treatment programs, or had not attended any sex offender program. On release, Tupiq participants had significantly lower rates of general reoffending and violent reoffending than those in the combined comparison group. The hazard of reoffending for the comparison group was almost twice that of the Tupiq group. Although the sexual reoffending rate for the Tupiq participants was less than half of that of the comparison group, the difference between the two groups was not significant because of reduced statistical power. Survival analysis controlling for covariates confirmed significantly lower rates of general reoffending for the Tupiq group. Further analyses comparing the outcomes of the subgroup of offenders in the comparison group who participated in alternative sex offender treatment programs with those who participated in Tupiq indicated that Tupiq participants had significantly lower rates of both general and sexual reoffending. These positive results for this culturally specific program suggest that similarly designed interventions have a probability of contributing to the reduction of sexual offending within Inuit communities and, potentially, other jurisdictions that work with cultural minority sex offender groups from relatively isolated communities. PMID:24913245

  8. Sex-specific divergence of antioxidant pathways in fetal brain, liver, and skeletal muscles.

    PubMed

    Al-Gubory, Kaïs H; Garrel, Catherine

    2016-01-01

    The sex-specific divergence of antioxidant pathways in fetal organs of opposite-sex twin is unknown and remains urgently in need of investigation. Such study faces many challenges, mainly the ethical impossibility of obtaining human fetal organs. Opposite-sex sheep twins represent a unique model for studying a sex dimorphism for antioxidant systems. The activity of total superoxide dismutase (SOD), SOD1, SOD2, glutathione peroxidase (GPX), glutathione reductase (GR) and catalase (CAT), the content of total glutathione, reduced glutathione (GSH), and oxidized glutathione (GSSG) were measured in brain, lung, liver, kidney, and skeletal muscles of female and male fetuses collected from sheep twin pregnancies at day 65 of gestation. Lipid peroxidation was assessed by measuring melondialdehyde (MDA) tissue content. Male brain has greater total SOD and SOD1 activities than female brain. Female liver has greater SOD2 activity than male liver. Male liver has greater GR activity than female liver. Male liver has higher total GSH and GSSG content than female liver. Male skeletal muscles have higher total GSH, GSH, and GSSG content than female skeletal muscles. Female brain and liver have higher MDA content than male brain and liver. This is the first report of a sex dimorphism for fetal organ antioxidative pathways. Brain, liver, and skeletal muscles of male and female fetuses display distinct antioxidant pathways. Such sexually dimorphic responses to early life oxidative stress might be involved in the sex-related difference in fetal development that may have a long-term effect on offspring. Our study urges researchers to take into consideration the importance of sex as a biologic variable in their investigations. PMID:26765668

  9. Sex-specific gonadal and gene expression changes throughout development in fathead minnow

    EPA Science Inventory

    Although fathead minnows (Pimephales promelas) are commonly used as a model fish in endocrine disruption studies, none have characterized sex-specific baseline expression of genes involved in sex differentiation during development in this species. Using a sex-linked DNA marker t...

  10. Sex Offender Recidivism Revisited: Review of Recent Meta-analyses on the Effects of Sex Offender Treatment.

    PubMed

    Kim, Bitna; Benekos, Peter J; Merlo, Alida V

    2016-01-01

    The effectiveness of sex offender treatment programs continues to generate misinformation and disagreement. Some literature reviews conclude that treatment does not reduce recidivism while others suggest that specific types of treatment may warrant optimism. The principal purpose of this study is to update the most recent meta-analyses of sex offender treatments and to compare the findings with an earlier study that reviewed the meta-analytic studies published from 1995 to 2002. More importantly, this study examines effect sizes across different age populations and effect sizes across various sex offender treatments. Results of this review of meta-analyses suggest that sex offender treatments can be considered as "proven" or at least "promising," while age of participants and intervention type may influence the success of treatment for sex offenders. The implications of these findings include achieving a broader understanding of intervention moderators, applying such interventions to juvenile and adult offenders, and outlining future areas of research. PMID:25575803

  11. 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.…

  12. Estimation of sex-specific survival from capture-recapture data when sex is not always known

    USGS Publications Warehouse

    Nichols, J.D.; Kendall, W.L.; Hines, J.E.; Spendelow, J.A.

    2004-01-01

    Many animals lack obvious sexual dimorphism, making assignment of sex difficult even for observed or captured animals. For many such species it is possible to assign sex with certainty only at some occasions; for example, when they exhibit certain types of behavior. A common approach to handling this situation in capture-recapture studies has been to group capture histories into those of animals eventually identified as male and female and those for which sex was never known. Because group membership is dependent on the number of occasions at which an animal was caught or observed (known sex animals, on average, will have been observed at more occasions than unknown-sex animals), survival estimates for known-sex animals will be positively biased, and those for unknown animals will be negatively biased. In this paper, we develop capture-recapture models that incorporate sex ratio and sex assignment parameters that permit unbiased estimation in the face of this sampling problem. We demonstrate the magnitude of bias in the traditional capture-recapture approach to this sampling problem, and we explore properties of estimators from other ad hoc approaches. The model is then applied to capture-recapture data for adult Roseate Terns (Sterna dougallii) at Falkner Island, Connecticut, 1993-2002. Sex ratio among adults in this population favors females, and we tested the hypothesis that this population showed sex-specific differences in adult survival. Evidence was provided for higher survival of adult females than males, as predicted. We recommend use of this modeling approach for future capture-recapture studies in which sex cannot always be assigned to captured or observed animals. We also place this problem in the more general context of uncertainty in state classification in multistate capture-recapture models.

  13. Sex-specific strategy use and global-local processing: a perspective toward integrating sex differences in cognition

    PubMed Central

    Pletzer, Belinda

    2014-01-01

    This article reviews the literature on sex-specific strategy use in cognitive tasks with the aim to carve out a link between sex differences in different cognitive tasks. I conclude that male strategies are commonly holistic and oriented toward global stimulus aspects, while female strategies are commonly decomposed and oriented toward local stimulus aspects. Thus, the strategies observed in different tasks, may depend on sex differences in attentional focus and hence sex differences in global-local processing. I hypothesize that strategy use may be sex hormone dependent and hence subject to change over the menstrual cycle as evidenced by findings in global-local processing and emotional memory. Furthermore, I propose sex hormonal modulation of hemispheric asymmetries as one possible neural substrate for this theory, thereby building on older theories, emphasizing the importance of sex differences in brain lateralization. The ideas described in the current article represent a perspective toward a unifying approach to the study of sex differences in cognition and their neural correlates. PMID:25565953

  14. Sex-specific influence of aging on exercising leg blood flow.

    PubMed

    Parker, Beth A; Smithmyer, Sandra L; Pelberg, Justin A; Mishkin, Aaron D; Proctor, David N

    2008-03-01

    Our previous work suggests that healthy human aging is associated with sex-specific differences in leg vascular responses during large muscle mass exercise (2-legged cycling) (Proctor DN, Parker BA. Microcirculation 13: 315-327, 2006). The present study determined whether age x sex interactions in exercising leg hemodynamics persist during small muscle mass exercise that is not limited by cardiac output. Thirty-one young (20-30 yr; 15 men/16 women) and 31 older (60-79 yr; 13 men/18 women) healthy, normally active adults performed graded single-leg knee extensions to maximal exertion. Femoral artery blood velocity and diameter (Doppler ultrasound), heart rate (ECG), and beat-to-beat arterial blood pressure (mean arterial pressure, radial artery tonometry) were measured during each 3-min work rate (4.8 and 8 W/stage for women and men, respectively). The results (means +/- SE) were as follows. Despite reduced resting leg blood flow and vascular conductance, older men exhibited relatively preserved exercising leg hemodynamic responses. Older women, by contrast, exhibited attenuated hyperemic (young: 52 +/- 3 ml.min(-1).W(-1); vs. older: 40 +/- 4 ml.min(-1).W(-1); P = 0.02) and vasodilatory responses (young: 0.56 +/- 0.06 ml.min(-1).mmHg(-1).W(-1) vs. older: 0.37 +/- 0.04 ml.min(-1).mmHg(-1) W(-1); P < 0.01) to exercise compared with young women. Relative (percentage of maximal) work rate comparisons of all groups combined also revealed attenuated vasodilator responses in older women (P < 0.01 for age x sex x work rate interaction). These sex-specific age differences were not abolished by consideration of hemoglobin, quadriceps muscle, muscle recruitment, and mechanical influences on muscle perfusion. Collectively, these findings suggest that local factors contribute to the sex-specific effects of aging on exercising leg hemodynamics in healthy adults. PMID:18162481

  15. Sex-specific Trans-regulatory Variation on the Drosophila melanogaster X Chromosome

    PubMed Central

    Stocks, Michael; Dean, Rebecca; Rogell, Björn; Friberg, Urban

    2015-01-01

    The X chromosome constitutes a unique genomic environment because it is present in one copy in males, but two copies in females. This simple fact has motivated several theoretical predictions with respect to how standing genetic variation on the X chromosome should differ from the autosomes. Unmasked expression of deleterious mutations in males and a lower census size are expected to reduce variation, while allelic variants with sexually antagonistic effects, and potentially those with a sex-specific effect, could accumulate on the X chromosome and contribute to increased genetic variation. In addition, incomplete dosage compensation of the X chromosome could potentially dampen the male-specific effects of random mutations, and promote the accumulation of X-linked alleles with sexually dimorphic phenotypic effects. Here we test both the amount and the type of genetic variation on the X chromosome within a population of Drosophila melanogaster, by comparing the proportion of X linked and autosomal trans-regulatory SNPs with a sexually concordant and discordant effect on gene expression. We find that the X chromosome is depleted for SNPs with a sexually concordant effect, but hosts comparatively more SNPs with a sexually discordant effect. Interestingly, the contrasting results for SNPs with sexually concordant and discordant effects are driven by SNPs with a larger influence on expression in females than expression in males. Furthermore, the distribution of these SNPs is shifted towards regions where dosage compensation is predicted to be less complete. These results suggest that intrinsic properties of dosage compensation influence either the accumulation of different types of trans-factors and/or their propensity to accumulate mutations. Our findings document a potential mechanistic basis for sex-specific genetic variation, and identify the X as a reservoir for sexually dimorphic phenotypic variation. These results have general implications for X chromosome

  16. The Effects of Sex of Subject, Sex and Attractiveness of Photo on Facial Recognition.

    ERIC Educational Resources Information Center

    Carroo, Agatha W.; Mozingo, R.

    1989-01-01

    Assessed effect of sex of subject, and sex and attractiveness of photo on facial recognition with 25 male and 25 female college students. Found male subjects performed better with male faces with d' prime scores. (Author/ABL)

  17. Sex Differences in Mechanisms and Outcome of Neonatal Hypoxia-Ischemia in Rodent Models: Implications for Sex-Specific Neuroprotection in Clinical Neonatal Practice

    PubMed Central

    Hill, Courtney A.; Fitch, R. Holly

    2012-01-01

    Clinical findings show that male infants with hypoxic-ischemic injury (HI) fare more poorly than matched females on cognitive outcomes. Rodent models of neonatal hypoxia-ischemia support this difference, with data showing that perinatal brain injury leads to long-term behavioral deficits primarily in male rodents and in female rodents treated with early androgens. Results support the idea that sex-specific gonadal hormones may modulate developmental response to injury and dovetail with overwhelming evidence of developmental androgen effects on typical brain morphology and behavior. However, mechanisms underlying sex differences in response to early brain injury may be more complicated. Specifically, activation of cell death pathways in response to HI may also differ by sex. In females, the preferential activation of the caspase-dependent apoptotic pathway may actually afford greater protection, potentially due to the actions of X-linked inhibitor of apoptosis (XIAP) within this pathway. This contrasts the pattern of preferential activation of the caspase-independent pathway in males. While an integrated model of sex-specific hormonal and genetic modulation of response to early injury remains to be fully elucidated, these findings suggest that infants might benefit from sex-specific neuroprotection following HI injury. PMID:22474588

  18. Sex differences in mechanisms and outcome of neonatal hypoxia-ischemia in rodent models: implications for sex-specific neuroprotection in clinical neonatal practice.

    PubMed

    Hill, Courtney A; Fitch, R Holly

    2012-01-01

    Clinical findings show that male infants with hypoxic-ischemic injury (HI) fare more poorly than matched females on cognitive outcomes. Rodent models of neonatal hypoxia-ischemia support this difference, with data showing that perinatal brain injury leads to long-term behavioral deficits primarily in male rodents and in female rodents treated with early androgens. Results support the idea that sex-specific gonadal hormones may modulate developmental response to injury and dovetail with overwhelming evidence of developmental androgen effects on typical brain morphology and behavior. However, mechanisms underlying sex differences in response to early brain injury may be more complicated. Specifically, activation of cell death pathways in response to HI may also differ by sex. In females, the preferential activation of the caspase-dependent apoptotic pathway may actually afford greater protection, potentially due to the actions of X-linked inhibitor of apoptosis (XIAP) within this pathway. This contrasts the pattern of preferential activation of the caspase-independent pathway in males. While an integrated model of sex-specific hormonal and genetic modulation of response to early injury remains to be fully elucidated, these findings suggest that infants might benefit from sex-specific neuroprotection following HI injury. PMID:22474588

  19. 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

  20. Transposon Insertions Causing Constitutive Sex-Lethal Activity in Drosophila Melanogaster Affect Sxl Sex-Specific Transcript Splicing

    PubMed Central

    Bernstein, M.; Lersch, R. A.; Subrahmanyan, L.; Cline, T. W.

    1995-01-01

    Sex-lethal (Sxl) gene products induce female development in Drosophila melanogaster and suppress the transcriptional hyperactivation of X-linked genes responsible for male X-chromosome dosage compensation. Control of Sxl functioning by the dose of X-chromosomes normally ensures that the female-specific functions of this developmental switch gene are only expressed in diplo-X individuals. Although the immediate effect of X-chromosome dose is on Sxl transcription, during most of the life cycle ``on'' vs. ``off'' reflects alternative Sxl RNA splicing, with the female (productive) splicing mode maintained by a positive feedback activity of SXL protein on Sxl pre-mRNA splicing. ``Male-lethal'' (Sxl(M)) gain-of-function alleles subvert Sxl control by X-chromosome dose, allowing female Sxl functions to be expressed independent of the positive regulators upstream of Sxl. As a consequence, Sxl(M) haplo-X animals (chromosomal males) die because of improper dosage compensation, and Sxl(M) chromosomal females survive the otherwise lethal effects of mutations in upstream positive regulators. Five independent spontaneous Sxl(M) alleles were shown previously to be transposon insertions into what was subsequently found to be the region of regulated sex-specific Sxl RNA splicing. We show that these five alleles represent three different mutant types: Sxl(M1), Sxl(M3), and Sxl(M4). Sxl(M1) is an insertion of a roo element 674 bp downstream of the translation-terminating male-specific exon. Sxl(M3) is an insertion of a hobo transposon (not 297 as previously reported) into the 3' splice site of the male exon, and Sxl(M4) is an insertion of a novel transposon into the male-specific exon itself. We show that these three gain-of-function mutants differ considerably in their ability to bypass the sex determination signal, with Sxl(M4) being the strongest and Sxl(M1) the weakest. This difference is also reflected in effects of these mutations on sex-specific RNA splicing and on the rate of

  1. Transposon insertions causing constitutive Sex-lethal activity in Drosophila melanogaster affect Sxl sex-specific transcript splicing.

    PubMed

    Bernstein, M; Lersch, R A; Subrahmanyan, L; Cline, T W

    1995-02-01

    Sex-lethal (Sxl) gene products induce female development in Drosophila melanogaster and suppress the transcriptional hyperactivation of X-linked genes responsible for male X-chromosome dosage compensation. Control of Sxl functioning by the dose of X-chromosomes normally ensures that the female-specific functions of this developmental switch gene are only expressed in diplo-X individuals. Although the immediate effect of X-chromosome dose is on Sxl transcription, during most of the life cycle "on" vs. "off" reflects alternative Sxl RNA splicing, with the female (productive) splicing mode maintained by a positive feedback activity of SXL protein on Sxl pre-mRNA splicing. "Male-lethal" (SxlM) gain-of-function alleles subvert Sxl control by X-chromosome dose, allowing female Sxl functions to be expressed independent of the positive regulators upstream of Sxl. As a consequence, SxlM haplo-X animals (chromosomal males) die because of improper dosage compensation, and SxlM chromosomal females survive the otherwise lethal effects of mutations in upstream positive regulators. Five independent spontaneous SxlM alleles were shown previously to be transposon insertions into what was subsequently found to be the region of regulated sex-specific Sxl RNA splicing. We show that these five alleles represent three different mutant types: SxlM1, SxlM3, and SxlM4. SxlM1 is an insertion of a roo element 674 bp downstream of the translation-terminating male-specific exon. SxlM3 is an insertion of a hobo transposon (not 297 as previously reported) into the 3' splice site of the male exon, and SxlM4 is an insertion of a novel transposon into the male-specific exon itself. We show that these three gain-of-function mutants differ considerably in their ability to bypass the sex determination signal, with SxlM4 being the strongest and SxlM1 the weakest. This difference is also reflected in effects of these mutations on sex-specific RNA splicing and on the rate of appearance of SXL protein in

  2. Sex-specific neural circuits of emotion regulation in the centromedial amygdala

    PubMed Central

    Wu, Yan; Li, Huandong; Zhou, Yuan; Yu, Jian; Zhang, Yuanchao; Song, Ming; Qin, Wen; Yu, Chunshui; Jiang, Tianzi

    2016-01-01

    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. PMID:27004933

  3. 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

    2016-01-01

    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. PMID:27004933

  4. Sex-specific risk of cardiovascular disease and cognitive decline: pregnancy and menopause

    PubMed Central

    2013-01-01

    Understanding the biology of sex differences is integral to personalized medicine. Cardiovascular disease and cognitive decline are two related conditions, with distinct sex differences in morbidity and clinical manifestations, response to treatments, and mortality. Although mortality from all-cause cardiovascular diseases has declined in women over the past five years, due in part to increased educational campaigns regarding the recognition of symptoms and application of treatment guidelines, the mortality in women still exceeds that of men. The physiological basis for these differences requires further research, with particular attention to two physiological conditions which are unique to women and associated with hormonal changes: pregnancy and menopause. Both conditions have the potential to impact life-long cardiovascular risk, including cerebrovascular function and cognition in women. This review draws on epidemiological, translational, clinical, and basic science studies to assess the impact of hypertensive pregnancy disorders on cardiovascular disease and cognitive function later in life, and examines the effects of post-menopausal hormone treatments on cardiovascular risk and cognition in midlife women. We suggest that hypertensive pregnancy disorders and menopause activate vascular components, i.e., vascular endothelium and blood elements, including platelets and leukocytes, to release cell-membrane derived microvesicles that are potential mediators of changes in cerebral blood flow, and may ultimately affect cognition in women as they age. Research into specific sex differences for these disease processes with attention to an individual’s sex chromosomal complement and hormonal status is important and timely. PMID:23537114

  5. Effects of Counselor Sex, Student Sex, and Student Attractiveness on Counselors' Judgments.

    ERIC Educational Resources Information Center

    Mercado, Pauline; Atkinson, Donald R.

    1982-01-01

    Studied the effect of client sex and attractiveness on male and female counselors' judgments about students' educational and career potential. Found male counselors showed sex bias when suggesting occupations. Prediction of higher education and occupational status were not related to counselor or student sex or student attractiveness. (Author/JAC)

  6. Effects of Physical Attractiveness, Sex and Sex-Role on Trait Attributions.

    ERIC Educational Resources Information Center

    Major, Brenda; Deaux, Kay

    This research investigates how androgynous men and women are evaluated relative to those who are sex-typed or sex reversed, and also investigates the joint effects of attractiveness and sex-role upon such evaluation. Two studies with replicable results were conducted. In each, approximately 185 male and 185 female undergraduates were asked to rate…

  7. Androstadienone's influence on the perception of facial and vocal attractiveness is not sex specific.

    PubMed

    Ferdenzi, Camille; Delplanque, Sylvain; Atanassova, Reni; Sander, David

    2016-04-01

    The androgen steroid androstadienone, an odorous compound emitted from the human axillary region, has recurrently been considered as a candidate compound involved in human chemical communication and mate choice. Although perception of androstadienone has been shown to influence several affective (mood), attentional, physiological and neural parameters, studies investigating its impact on human attractiveness remain unpersuasive because of incomplete designs (e.g., only female participants) and contradictory results. The aim of this study was to investigate how androstadienone may influence others' attractiveness. Specifically, we used a complete design (male and female raters, male and female faces and voices) to determine whether androstadienone influences the perception of social stimuli in a sex-specific manner, which would favor pheromonal-like properties of the compound, or in a more general manner, which would suggest that the compound has broader influences on human psychological responses. After comparing the ratings of men and women who were exposed to androstadienone masked in clove oil with those of men and women who were exposed to clove oil alone, we found that androstadienone enhanced the perceived attractiveness of emotionally relevant stimuli (opposite-sex stimuli in men and in fertile women). Response times for categorizing the stimuli as attractive or not were also affected by androstadienone, with longer response times in men and in fertile women and shorter response times in non-fertile women, irrespective of the stimulus sex. The results favor the hypothesis of general effects over sex-specific effects of androstadienone, thus questioning the relevance of focusing on that particular compound in the study of human attractiveness through body odor and encouraging the search for other semiochemicals that might be significant for human mate choice. PMID:26827295

  8. Development of a transgenic sexing system based on female-specific embryonic lethality in Ceratitis capitata (Diptera: Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Sterile Insect Technique (SIT) is more efficient and cost-effective when only sterile males are released. A female-specific lethality system based on a female-specifically spliced intron was developed for transgenic sexing in Ceratitis capitata (Fu et al., 2007) possibly to overcome the fitness ...

  9. Sex, Drugs, and Cognition: Effects of Marijuana†

    PubMed Central

    Anderson, Beth M.; Rizzo, Matthew; Block, Robert I.; Pearlson, Godfrey D.; O'Leary, Daniel S.

    2011-01-01

    Despite the knowledge that many drugs affect men and women differently, few studies exploring the effects of marijuana use on cognition have included women. Findings from both animal and human studies suggest marijuana may have more marked effects in women. This study examined sex differences in the acute effects of marijuana on cognition in 70 (n= 35 male, 35 female) occasional users of marijuana. Tasks were chosen to tap a wide variety of cognitive domains affected by sex and/or marijuana including attention, cognitive flexibility, time estimation, and visuospatial processing. As expected, acute marijuana use impaired performance on selective and divided attention, time estimation, and cognitive flexibility. While there did not appear to be sex differences in marijuana's effects on cognition, women requested to discontinue the smoking session more often than men likely leading to an underestimation of differences. Further study of psychological differences in marijuana's effects on men and women following both acute and residual effects of marijuana is warranted. PMID:21305906

  10. Sex-specific vitellogenin production in immature rainbow trout

    SciTech Connect

    Carlson, D.B.; Williams, D.E.

    1999-10-01

    Many xenobiotics interact with hormone systems of animals, potentially leading to a phenomenon commonly called endocrine disruption. Much attention has focused on steroid hormone systems and corresponding receptor proteins, particularly estrogens. Vitellogenin (Vg) was measured in sexually immature rainbow trout (Oncorhynchus mykiss) exposed to 17{beta}-estradiol (E{sub 2}) in the diet. Mixed-sex populations of trout aged 3, 6, 12, or 18 months were maintained separately and fed E{sub 2} at 0.05 or 2.5 mg/kg for 7d. Females fed E{sub 2} at 0.05 mg/kg consistently produced three- to fourfold greater amounts of Vg than similarly aged males. Age- and sex-matched fish fed E{sub 2} at 2.5 mg/kg produced equivalent amounts of Vg. Sex differences in Vg production were apparent only at a dose of E{sub 2} (0.05 mg/kg) that results in submaximal Vg induction. Their results document the importance of considering the sex of juvenile fish when using Vg production as a marker of xenoestrogen exposure.

  11. Testing the Effects of DL-Alpha-Tocopherol Supplementation on Oxidative Damage, Total Antioxidant Protection and the Sex-Specific Responses of Reproductive Effort and Lifespan to Dietary Manipulation in Australian Field Crickets (Teleogryllus commodus).

    PubMed

    Archer, C Ruth; Hempenstall, Sarah; Royle, Nick J; Selman, Colin; Willis, Sheridan; Rapkin, James; Blount, Jon D; Hunt, John

    2015-01-01

    The oxidative stress theory predicts that the accumulation of oxidative damage causes aging. More generally, oxidative damage could be a cost of reproduction that reduces survival. Both of these hypotheses have mixed empirical support. To better understand the life-history consequences of oxidative damage, we fed male and female Australian field crickets (Teleogryllus commodus) four diets differing in their protein and carbohydrate content, which have sex-specific effects on reproductive effort and lifespan. We supplemented half of these crickets with the vitamin E isoform DL-alpha-tocopherol and measured the effects of nutrient intake on lifespan, reproduction, oxidative damage and antioxidant protection. We found a clear trade-off between reproductive effort and lifespan in females but not in males. In direct contrast to the oxidative stress theory, crickets fed diets that improved their lifespan had high levels of oxidative damage to proteins. Supplementation with DL-alpha-tocopherol did not significantly improve lifespan or reproductive effort. However, males fed diets that increased their reproductive investment experienced high oxidative damage to proteins. While this suggests that male reproductive effort could elevate oxidative damage, this was not associated with reduced male survival. Overall, these results provide little evidence that oxidative damage plays a central role in mediating life-history trade-offs in T. commodus. PMID:26783958

  12. Sex-specific effects of cytotoxic chemotherapy agents cyclophosphamide and mitomycin C on gene expression, oxidative DNA damage, and epigenetic alterations in the prefrontal cortex and hippocampus - an aging connection.

    PubMed

    Kovalchuk, Anna; Rodriguez-Juarez, Rocio; Ilnytskyy, Yaroslav; Byeon, Boseon; Shpyleva, Svitlana; Melnyk, Stepan; Pogribny, Igor; Kolb, Bryan; Kovalchuk, Olga

    2016-04-01

    Recent research shows that chemotherapy agents can be more toxic to healthy brain cells than to the target cancer cells. They cause a range of side effects, including memory loss and cognitive dysfunction that can persist long after the completion of treatment. This condition is known as chemo brain. The molecular and cellular mechanisms of chemo brain remain obscure. Here, we analyzed the effects of two cytotoxic chemotherapy drugs-cyclophosphamide (CPP) and mitomycin C (MMC) - on transcriptomic and epigenetic changes in the murine prefrontal cortex (PFC) and hippocampal regions. We for the first time showed that CPP and MMC treatments led to profound sex- and brain region-specific alterations in gene expression profiles. Gene expression changes were most prominent in the PFC tissues of female mice 3 weeks after MMC treatment, and the gene expression response was much greater for MCC than CPP exposure. MMC exposure resulted in oxidative DNA damage, evidenced by accumulation of 8-oxo-2'-deoxyguanosine (8-oxodG) and a decrease in the level of 8-oxodG repair protein OGG1 in the PFC of female animals 3 weeks after treatment. MMC treatment decreased global DNA methylation and increased DNA hydroxymethylation in the PFC tissues of female mice. The majority of the changes induced by chemotherapy in the PFC tissues of female mice resembled those that occur during the brain's aging processes. Therefore, our study suggests a link between chemotherapy-induced chemo brain and brain aging, and provides an important roadmap for future analysis. PMID:27032448

  13. Testing the Effects of dl-Alpha-Tocopherol Supplementation on Oxidative Damage, Total Antioxidant Protection and the Sex-Specific Responses of Reproductive Effort and Lifespan to Dietary Manipulation in Australian Field Crickets (Teleogryllus commodus)

    PubMed Central

    Archer, C. Ruth; Hempenstall, Sarah; Royle, Nick J.; Selman, Colin; Willis, Sheridan; Rapkin, James; Blount, Jon D.; Hunt, John

    2015-01-01

    The oxidative stress theory predicts that the accumulation of oxidative damage causes aging. More generally, oxidative damage could be a cost of reproduction that reduces survival. Both of these hypotheses have mixed empirical support. To better understand the life-history consequences of oxidative damage, we fed male and female Australian field crickets (Teleogryllus commodus) four diets differing in their protein and carbohydrate content, which have sex-specific effects on reproductive effort and lifespan. We supplemented half of these crickets with the vitamin E isoform dl-alpha-tocopherol and measured the effects of nutrient intake on lifespan, reproduction, oxidative damage and antioxidant protection. We found a clear trade-off between reproductive effort and lifespan in females but not in males. In direct contrast to the oxidative stress theory, crickets fed diets that improved their lifespan had high levels of oxidative damage to proteins. Supplementation with dl-alpha-tocopherol did not significantly improve lifespan or reproductive effort. However, males fed diets that increased their reproductive investment experienced high oxidative damage to proteins. While this suggests that male reproductive effort could elevate oxidative damage, this was not associated with reduced male survival. Overall, these results provide little evidence that oxidative damage plays a central role in mediating life-history trade-offs in T. commodus. PMID:26783958

  14. Distributed Effects of Biological Sex Define Sex-Typical Motor Behavior in Caenorhabditis elegans

    PubMed Central

    Mowrey, William R.; Bennett, Jessica R.

    2014-01-01

    Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology. PMID:24478342

  15. Apolipoprotein E and Alzheimer disease: Genotype-specific risks by age and sex

    SciTech Connect

    Bickeboeller, H. |; Babron, M.C.; Clerget-Darpoux, F.

    1997-02-01

    The distribution of apolipoprotein E (APOE) genotypes as a function of age and sex has been examined in a French population of 417 Alzheimer disease (AD) patients and 1,030 control subjects. When compared to the APOE {epsilon}3 allele, an increased risk associated with the APOE {epsilon}4 allele (odds ratio [OR] [{epsilon}4] = 2.7 with 95% confidence interval [CI] = 2.0-3.6; P < .001) and a protective effect of the APOE {epsilon}2 allele (OR[{epsilon}2] = 0.5 with 95% CI = 0.3-0.98; P = .012) were retrieved. An effect of the {epsilon}4 allele dosage on susceptibility was confirmed (OR[{epsilon}4/{epsilon}4] vs. the {epsilon}3/{epsilon}3 genotype = 11.2 [95% CI = 4.0-31.6]; OR[{epsilon}3/{epsilon}4] vs. the {epsilon}3/{epsilon}3 genotype = 2.2 [95% Cl = 1.5-3.5]). The frequency of the {epsilon}4 allele was lower in male cases than in female cases, but, since a similar difference was found in controls, this does not lead to a difference in OR between sex. ORs for the {epsilon}4 allele versus the {epsilon}3 allele, OR({epsilon}4), were not equal in all age classes: OR({epsilon}4) in the extreme groups with onset at < 60 years or > 79 years were significantly lower than those from the age groups 60-79 years. In {epsilon}3/{epsilon}4 individuals, sex-specific lifetime risk estimates by age 85 years (i.e., sex-specific penetrances by age 85 years) were 0.14 (95% CI 0.04-0.30) for men and 0.17 (95% CI 0.09-0.28) for women. 53 refs., 1 fig., 3 tabs.

  16. Apolipoprotein E and Alzheimer disease: genotype-specific risks by age and sex.

    PubMed Central

    Bickeböller, H; Campion, D; Brice, A; Amouyel, P; Hannequin, D; Didierjean, O; Penet, C; Martin, C; Pérez-Tur, J; Michon, A; Dubois, B; Ledoze, F; Thomas-Anterion, C; Pasquier, F; Puel, M; Demonet, J F; Moreaud, O; Babron, M C; Meulien, D; Guez, D; Chartier-Harlin, M C; Frebourg, T; Agid, Y; Martinez, M; Clerget-Darpoux, F

    1997-01-01

    The distribution of apolipoprotein E (APOE) genotypes as a function of age and sex has been examined in a French population of 417 Alzheimer disease (AD) patients and 1,030 control subjects. When compared to the APOE epsilon3 allele, an increased risk associated with the APOE epsilon4 allele (odds ratio [OR] [epsilon4] = 2.7 with 95% confidence interval [CI] = 2.0-3.6; P < .001) and a protective effect of the APOE epsilon2 allele (OR[epsilon2] = 0.5 with 95% CI = 0.3-0.98; P = .012) were retrieved. An effect of the epsilon4 allele dosage on susceptibility was confirmed (OR[epsilon4/epsilon4] vs. the epsilon3/epsilon3 genotype = 11.2 [95% CI = 4.0-31.6]; OR[epsilon3/epsilon4] vs. the epsilon3/epsilon3 genotype = 2.2 [95% CI = 1.5-3.5]). The frequency of the epsilon4 allele was lower in male cases than in female cases, but, since a similar difference was found in controls, this does not lead to a difference in OR between sex. ORs for the epsilon4 allele versus the epsilon3 allele, OR(epsilon4), were not equal in all age classes: OR(epsilon4) in the extreme groups with onset at < 60 years or > 79 years were significantly lower than those from the age groups 60-79 years. In epsilon3/epsilon4 individuals, sex-specific lifetime risk estimates by age 85 years (i.e., sex-specific penetrances by age 85 years) were 0.14 (95% CI 0.04-0.30) for men and 0.17 (95% CI 0.09-0.28) for women. PMID:9012418

  17. 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

  18. Molecular genetic dissection of the sex-specific and vital functions of the Drosophila melanogaster sex determination gene fruitless.

    PubMed Central

    Anand, A; Villella, A; Ryner, L C; Carlo, T; Goodwin, S F; Song, H J; Gailey, D A; Morales, A; Hall, J C; Baker, B S; Taylor, B J

    2001-01-01

    A multibranched hierarchy of regulatory genes controls all aspects of somatic sexual development in Drosophila melanogaster. One branch of this hierarchy is headed by the fruitless (fru) gene and functions in the central nervous system, where it is necessary for male courtship behavior as well as the differentiation of a male-specific abdominal structure, the muscle of Lawrence (MOL). A preliminary investigation of several of the mutations described here showed that the fru gene also has a sex-nonspecific vital function. The fru gene produces a complex set of transcripts through the use of four promoters and alternative splicing. Only the primary transcripts produced from the most distal (P1) promoter are sex-specifically spliced under direction of the sex-determination hierarchy. We have analyzed eight new fru mutations, created by X-ray mutagenesis and P-element excision, to try to gain insight into the relationship of specific transcript classes to specific fru functions. Males that lack the P1-derived fru transcripts show a complete absence of sexual behavior, but no other defects besides the loss of the MOL. Both males and females that have reduced levels of transcripts from the P3 promoter develop into adults but frequently die after failing to eclose. Analysis of the morphology and behavior of adult escapers showed that P3-encoded functions are required for the proper differentiation and eversion of imaginal discs. Furthermore, the reduction in the size of the neuromuscular junctions on abdominal muscles in these animals suggests that one of fru's sex-nonspecific functions involves general aspects of neuronal differentiation. In mutants that lack all fru transcripts as well as a small number of adjacent genes, animals die at an early pupal stage, indicating that fru's function is required only during late development. Thus, fru functions both in the sex-determination regulatory hierarchy to control male sexual behavior through sex-specific transcripts and

  19. 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.

  20. High-density sex-specific linkage maps of a European tree frog (Hyla arborea) identify the sex chromosome without information on offspring sex.

    PubMed

    Brelsford, A; Dufresnes, C; Perrin, N

    2016-02-01

    Identifying homology between sex chromosomes of different species is essential to understanding the evolution of sex determination. Here, we show that the identity of a homomorphic sex chromosome pair can be established using a linkage map, without information on offspring sex. By comparing sex-specific maps of the European tree frog Hyla arborea, we find that the sex chromosome (linkage group 1) shows a threefold difference in marker number between the male and female maps. In contrast, the number of markers on each autosome is similar between the two maps. We also find strongly conserved synteny between H. arborea and Xenopus tropicalis across 200 million years of evolution, suggesting that the rate of chromosomal rearrangement in anurans is low. Finally, we show that recombination in males is greatly reduced at the centers of large chromosomes, consistent with previous cytogenetic findings. Our research shows the importance of high-density linkage maps for studies of recombination, chromosomal rearrangement and the genetic architecture of ecologically or economically important traits. PMID:26374238

  1. Depleted uranium induces sex- and tissue-specific methylation patterns in adult zebrafish.

    PubMed

    Gombeau, Kewin; Pereira, Sandrine; Ravanat, Jean-Luc; Camilleri, Virginie; Cavalie, Isabelle; Bourdineaud, Jean-Paul; Adam-Guillermin, Christelle

    2016-04-01

    We examined the effects of chronic exposure to different concentrations (2 and 20 μg L(-)(1)) of environmentally relevant waterborne depleted uranium (DU) on the DNA methylation patterns both at HpaII restriction sites (5'-CCGG-3') and across the whole genome in the zebrafish brain, gonads, and eyes. We first identified sex-dependent differences in the methylation level of HpaII sites after exposure. In males, these effects were present as early as 7 days after exposure to 20 μg L(-)(1) DU, and were even more pronounced in the brain, gonads, and eyes after 24 days. However, in females, hypomethylation was only observed in the gonads after exposure to 20 μg L(-)(1) DU for 24 days. Sex-specific effects of DU were also apparent at the whole-genome level, because in males, exposure to 20 μg L(-)(1) DU for 24 days resulted in cytosine hypermethylation in the brain and eyes and hypomethylation in the gonads. In contrast, in females, hypermethylation was observed in the brain after exposure to both concentrations of DU for 7 days. Based on our current knowledge of uranium toxicity, several hypotheses are proposed to explain these findings, including the involvement of oxidative stress, alteration of demethylation enzymes and the calcium signaling pathway. This study reports, for the first time, the sex- and tissue-specific epigenetic changes that occur in a nonhuman organism after exposure to environmentally relevant concentrations of uranium, which could induce transgenerational epigenetic effects. PMID:26829549

  2. Sex-specific demography and generalization of the Trivers-Willard theory

    NASA Astrophysics Data System (ADS)

    Schindler, Susanne; Gaillard, Jean-Michel; Grüning, André; Neuhaus, Peter; Traill, Lochran W.; Tuljapurkar, Shripad; Coulson, Tim

    2015-10-01

    The Trivers-Willard theory proposes that the sex ratio of offspring should vary with maternal condition when it has sex-specific influences on offspring fitness. In particular, mothers in good condition in polygynous and dimorphic species are predicted to produce an excess of sons, whereas mothers in poor condition should do the opposite. Despite the elegance of the theory, support for it has been limited. Here we extend and generalize the Trivers-Willard theory to explain the disparity between predictions and observations of offspring sex ratio. In polygynous species, males typically have higher mortality rates, different age-specific reproductive schedules and more risk-prone life history tactics than females; however, these differences are not currently incorporated into the Trivers-Willard theory. Using two-sex models parameterized with data from free-living mammal populations with contrasting levels of sex differences in demography, we demonstrate how sex differences in life history traits over the entire lifespan can lead to a wide range of sex allocation tactics, and show that correlations between maternal condition and offspring sex ratio alone are insufficient to conclude that mothers adaptively adjust offspring sex ratio.

  3. Hypothesis: gonadal temperature influences sex-specific imprinting

    PubMed Central

    Donti, Emilio

    2014-01-01

    Various explanations have been advanced for the evolution of genomic imprinting, the most popular of these being the parental conflict hypothesis. However, while this theory may explain why there has been selection for imprinting certain genes, it does not explain how the maternal and paternal genomes can be distinguished from each other. Here, we hypothesize that the temperature at which male and female gonads are physiologically exposed could be, at least for some loci, the primary factor leading to the different imprinting between the sexes. PMID:25202325

  4. Age- and sex-specific mortality and population structure in sea otters

    USGS Publications Warehouse

    Bodkin, J.L.; Burdin, A.M.; Ryazanov, D.A.

    2000-01-01

    We used 742 beach-cast carcasses to characterize age- and sex-specific sea otter mortality during the winter of 1990-1991 at Bering Island, Russia. We also examined 363 carcasses recovered after the 1989 grounding of the T/V Exxon Valdez, to characterize age and sex composition in the living western Prince William Sound (WPWS) sea otter population. At Bering Island, mortality was male-biased (81%), and 75% were adults. The WPWS population was female-biased (59%) and most animals were subadult (79% of the males and 45% of the females). In the decade prior to 1990-1991 we found increasing sea otter densities (particularly among males), declining prey resources, and declining weights in adult male sea otters at Bering Island. Our findings suggest the increased mortality at Bering Island in 1990-1991 was a density-dependent population response. We propose male-maintained breeding territories and exclusion of juvenile females by adult females, providing a mechanism for potentially moderating the effects of prey reductions on the female population. Increased adult male mortality at Bearing Island in 1990-1991 likely modified the sex and age class structure there toward that observed in Prince William Sound.

  5. Enforcement following 0.08% BAC law change: sex-specific consequences of changing arrest practices?

    PubMed

    Schwartz, Jennifer; Davaran, Ardavan

    2013-10-01

    This research evaluated effects of stricter 0.08% BAC drunken driving law on changes in sex-specific DUI arrest rates, controlling for increased law enforcement resources and shifts in DUI-related behaviors. Another main purpose, the study assessed female/male differences in arrest increases due to broader enforcement standards and efforts. Panel data was assembled for 24 states over 1990-2007 on DUI arrests, alcohol policy, law enforcement resources, drinking and drunken driving prevalence. Two-way fixed-effects seemingly unrelated regression models predicted female versus male changes in DUI arrests following implementation of lower legal limits of intoxication, net controls. Findings suggest, first, that a broader legal definition of drunken driving intending to officially sanction less serious offenders (0.08% vs. 0.10% BAC) was associated with increased DUI arrests for both sexes. Second, growth in specialized DUI-enforcement units also was related to increased arrests. Whereas male and female arrest trends were equally affected by the direct net-widening effects of 0.08% BAC alcohol-policy, specialized DUI-enforcement efforts to dig deeper into the offender-pool had stronger arrest-producing effects on females, particularly prior to law change. Specifying how changes in law and enforcement resources affect arrest outcomes is an important pre-cursor to alcohol-policy analyses of effectiveness. A potential unintended consequence, effects of law and enforcement may differ across population segments. PMID:23773958

  6. Sex-specific effects of cytotoxic chemotherapy agents cyclophospha-mide and mitomycin C on gene expression, oxidative DNA damage, and epigenetic alterations in the prefrontal cortex and hippocampus – an aging connection

    PubMed Central

    Kovalchuk, Anna; Rodriguez-Juarez, Rocio; Ilnytskyy, Yaroslav; Byeon, Boseon; Shpyleva, Svitlana; Melnyk, Stepan; Pogribny, Igor; Kolb, Bryan; Kovalchuk, Olga

    2016-01-01

    Recent research shows that chemotherapy agents can be more toxic to healthy brain cells than to the target cancer cells. They cause a range of side effects, including memory loss and cognitive dysfunction that can persist long after the completion of treatment. This condition is known as chemo brain. The molecular and cellular mechanisms of chemo brain remain obscure. Here, we analyzed the effects of two cytotoxic chemotherapy drugs—cyclophosphamide (CPP) and mitomycin C (MMC) - on transcriptomic and epigenetic changes in the murine prefrontal cortex (PFC) and hippocampal regions. We for the first time showed that CPP and MMC treatments led to profound sex- and brain region-specific alterations in gene expression profiles. Gene expression changes were most prominent in the PFC tissues of female mice 3 weeks after MMC treatment, and the gene expression response was much greater for MCC than CPP exposure. MMC exposure resulted in oxidative DNA damage, evidenced by accumulation of 8-oxo-2′-deoxyguanosine (8-oxodG) and a decrease in the level of 8-oxodG repair protein OGG1 in the PFC of female animals 3 weeks after treatment. MMC treatment decreased global DNA methylation and increased DNA hydroxymethylation in the PFC tissues of female mice. The majority of the changes induced by chemotherapy in the PFC tissues of female mice resembled those that occur during the brain's aging processes. Therefore, our study suggests a link between chemotherapy-induced chemo brain and brain aging, and provides an important roadmap for future analysis. PMID:27032448

  7. Sex- and melanism-specific variations in the oxidative status of adult tawny owls in response to manipulated reproductive effort.

    PubMed

    Emaresi, Guillaume; Henry, Isabelle; Gonzalez, Esther; Roulin, Alexandre; Bize, Pierre

    2016-01-01

    Oxidative stress, determined by the balance between the production of damaging reactive oxygen species (ROS) and antioxidant defences, is hypothesized to play an important role in shaping the cost of reproduction and life history trade-offs. To test this hypothesis, we manipulated reproductive effort in 94 breeding pairs of tawny owls (Strix aluco) to investigate the sex- and melanism-specific effects on markers of oxidative stress in red blood cells (RBCs). This colour polymorphic bird species shows sex-specific division of labour and melanism-specific history strategies. Brood sizes at hatching were experimentally enlarged or reduced to increase or decrease reproductive effort, respectively. We obtained an integrative measure of the oxidative balance by measuring ROS production by RBCs, intracellular antioxidant glutathione levels and membrane resistance to ROS. We found that light melanic males (the sex undertaking offspring food provisioning) produced more ROS than darker conspecifics, but only when rearing an enlarged brood. In both sexes, light melanic individuals had also a larger pool of intracellular antioxidant glutathione than darker owls under relaxed reproductive conditions (i.e. reduced brood), but not when investing substantial effort in current reproduction (enlarged brood). Finally, resistance to oxidative stress was differently affected by the brood size manipulation experiment in males and females independently of their plumage coloration. Altogether, our results support the hypothesis that reproductive effort can alter the oxidative balance in a sex- and colour-specific way. This further emphasizes the close link between melanin-based coloration and life history strategies. PMID:26567343

  8. Empirical evidence for large X-effects in animals with undifferentiated sex chromosomes.

    PubMed

    Dufresnes, Christophe; Majtyka, Tomasz; Baird, Stuart J E; Gerchen, Jörn F; Borzée, Amaël; Savary, Romain; Ogielska, Maria; Perrin, Nicolas; Stöck, Matthias

    2016-01-01

    Reproductive isolation is crucial for the process of speciation to progress. Sex chromosomes have been assigned a key role in driving reproductive isolation but empirical evidence from natural population processes has been restricted to organisms with degenerated sex chromosomes such as mammals and birds. Here we report restricted introgression at sex-linked compared to autosomal markers in a hybrid zone between two incipient species of European tree frog, Hyla arborea and H. orientalis, whose homologous X and Y sex chromosomes are undifferentiated. This large X-effect cannot result from the dominance or faster-X aspects of Haldane's rule, which are specific to degenerated sex chromosomes, but rather supports a role for faster-heterogametic-sex or faster-male evolutionary processes. Our data suggest a prominent contribution of undifferentiated sex chromosomes to speciation. PMID:26868373

  9. Empirical evidence for large X-effects in animals with undifferentiated sex chromosomes

    PubMed Central

    Dufresnes, Christophe; Majtyka, Tomasz; Baird, Stuart J. E.; Gerchen, Jörn F.; Borzée, Amaël; Savary, Romain; Ogielska, Maria; Perrin, Nicolas; Stöck, Matthias

    2016-01-01

    Reproductive isolation is crucial for the process of speciation to progress. Sex chromosomes have been assigned a key role in driving reproductive isolation but empirical evidence from natural population processes has been restricted to organisms with degenerated sex chromosomes such as mammals and birds. Here we report restricted introgression at sex-linked compared to autosomal markers in a hybrid zone between two incipient species of European tree frog, Hyla arborea and H. orientalis, whose homologous X and Y sex chromosomes are undifferentiated. This large X-effect cannot result from the dominance or faster-X aspects of Haldane’s rule, which are specific to degenerated sex chromosomes, but rather supports a role for faster-heterogametic-sex or faster-male evolutionary processes. Our data suggest a prominent contribution of undifferentiated sex chromosomes to speciation. PMID:26868373

  10. Sex-specific alterations in behavioral and cognitive functions in a "three hit" animal model of schizophrenia.

    PubMed

    Kekesi, G; Petrovszki, Z; Benedek, G; Horvath, G

    2015-05-01

    Whereas schizophrenia affects both human sexes, there are known sex-dependent disparities. We developed a chronic animal model that shows some schizophrenia-related deficits in rats by applying selective breeding after subchronic ketamine administration connected with postweaning social isolation (complex treatment). Our aim was to determine the sex-specific effects of these interventions on several processes. Sensory gating to acoustic stimulation, pain sensitivity, motor behavior, spatial learning and memory deficits on the hole-board test were assessed in the 17th generation of selectively bred Wistar rats compared to their naive counterparts with or without complex treatment. We found differences between the sexes: selectively bred males with complex treatment showed the lowest pain sensitivity; however, the results of the prepulse inhibition test indicated that female rats showed enhanced impairment of sensory gating and increased acoustic startle reaction. The cognitive performance, working and reference memory ratios were significantly decreased by selective breeding and showed sex-specific alterations, with the smallest value in male rats of the new substrain. Based on these results, the animals of the new substrain could be classified into the high-risk for schizophreniform phenotype with the highest sensitivity of males with complex treatment. Decreased cognitive performance highlighted spatial learning deficits in the selectively bred and treated rats that escalate the validity of our new and complex rat model of schizophrenia. The results indicate the same sex selectivity as observed in humans, with increased incidence of risk ratios for men to develop schizophrenia relative to women. PMID:25698594

  11. Chronic disuse and skeletal muscle structure in older adults: sex-specific differences and relationships to contractile function

    PubMed Central

    Callahan, Damien M.; Tourville, Timothy W.; Miller, Mark S.; Hackett, Sarah B.; Sharma, Himani; Cruickshank, Nicholas C.; Slauterbeck, James R.; Savage, Patrick D.; Ades, Philip A.; Maughan, David W.; Beynnon, Bruce D.

    2015-01-01

    In older adults, we examined the effect of chronic muscle disuse on skeletal muscle structure at the tissue, cellular, organellar, and molecular levels and its relationship to muscle function. Volunteers with advanced-stage knee osteoarthritis (OA, n = 16) were recruited to reflect the effects of chronic lower extremity muscle disuse and compared with recreationally active controls (n = 15) without knee OA but similar in age, sex, and health status. In the OA group, quadriceps muscle and single-fiber cross-sectional area were reduced, with the largest reduction in myosin heavy chain IIA fibers. Myosin heavy chain IIAX fibers were more prevalent in the OA group, and their atrophy was sex-specific: men showed a reduction in cross-sectional area, and women showed no differences. Myofibrillar ultrastructure, myonuclear content, and mitochondrial content and morphology generally did not differ between groups, with the exception of sex-specific adaptations in subsarcolemmal (SS) mitochondria, which were driven by lower values in OA women. SS mitochondrial content was also differently related to cellular and molecular functional parameters by sex: greater SS mitochondrial content was associated with improved contractility in women but reduced function in men. Collectively, these results demonstrate sex-specific structural phenotypes at the cellular and organellar levels with chronic disuse in older adults, with novel associations between energetic and contractile systems. PMID:25810256

  12. [Gender medicine. Sex- and gender-specific aspects of clinical medicine].

    PubMed

    Kautzky-Willer, A

    2014-09-01

    Gender medicine studies sex- and gender-based differences in the development and prevention of diseases, the awareness and presentation of symptoms, and the effectiveness of therapy. Gender medicine is part of personalized medicine, considering differences in biological and psychosocial factors individually. There are differences in genes, chromosomes, hormones, and metabolism as well as differences in culture, environment, and society. Lifelong interactions between physical and psychosocial factors will influence the health and ill-health of men and women in different ways. Epigenetic modifications provide evidence of the impact of environment and lifestyle during vulnerable phases on biological processes, effecting future generations. Maternal lifestyle and environmental factors during pregnancy can impact the health of offspring in later life already in utero in a sex-specific way. Pain, stress, and coping styles differ between men and women. Women experience more dramatic physical changes during their lifetime, which are associated with specific burdens and psychosocial alterations. Women with multiple roles and responsibilities suffering from stress develop depression more frequently. However, men are often not diagnosed and treated appropriately in cases of depression or osteoporosis, diseases that are typically considered "female." There are prominent differences between men and women in medicine regarding the immune system, inflammation, and noncommunicable diseases such as obesity, type 2 diabetes, hypertension, and cardiovascular disease. Women experience more often autoimmune diseases and suffer more frequently from (chronic) pain, neurodegenerative changes, and functional disabilities. Men have shorter life expectancy but relatively more healthy years of life, which is in greater part ascribed to psychosocial determinants. State-of-the-art clinical medicine comprises individual risk factors based on sex- and gender-sensitive health programs in order to

  13. Effect of Single-Sex Education on Progress in GCSE

    ERIC Educational Resources Information Center

    Malacova, Eva

    2007-01-01

    Multilevel modeling was carried out on national value-added data to study the effects of single-sex education on the progress of pupils from 2002 Key Stage 3 to 2004 GCSE. The analysis suggests that pupils in a selective environment achieve higher progress in single-sex schools; however, the advantage of single-sex schooling seems to decrease with…

  14. Compound- and sex-specific effects on programming of energy and immune homeostasis in adult C57BL/6JxFVB mice after perinatal TCDD and PCB 153.

    PubMed

    van Esterik, J C J; Verharen, H W; Hodemaekers, H M; Gremmer, E R; Nagarajah, B; Kamstra, J H; Dollé, M E T; Legler, J; van der Ven, L T M

    2015-12-01

    Early life exposure to endocrine disrupting compounds has been linked to chronic diseases later in life, like obesity and related metabolic disorders. We exposed C57BL/6JxFVB hybrid mice to the aryl hydrocarbon receptor agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and the constitutive androstane receptor/pregnane X receptor agonist polychlorinated biphenyl 153 (PCB 153) in an experimental design relevant for human exposure. Exposure occurred during gestation and lactation via maternal feed to a wide dose range (TCDD: 10-10,000 pg/kg body weight/day; PCB 153: 0.09-1406 μg/kg body weight/d). Then exposure was ceased and offspring were followed up to 1 year of age. Metabolic parameters like body weight, fat pad weights, glucose tolerance, endocrine serum profile, and neurobehavioral and immunological parameters were determined. Body weight was transiently affected by both compounds throughout the follow-up. TCDD-exposed males showed decreased fat pad and spleen weights and an increase in IL-4 production of splenic immune cells. In contrast, females showed increased fat pad weights and production of IFNγ. PCB 153-exposed males showed an increase in glucose, whereas females showed an increase in glucagon, a decrease in pancreas weight, and an increase in thymus weight. In conclusion, early life exposure to TCDD appears to affect programming of energy and immune homeostasis in offspring, whereas the effects of perinatal PCB 153 were mainly on programming of glucose homeostasis. Both compounds act sex-specifically. Lowest derived BMDLs (lower bounds of the (two sided) 90%-confidence interval for the benchmark dose) for both compounds are not lower than current tolerable daily intakes. PMID:26415833

  15. Glia-derived neurons are required for sex-specific learning in C. elegans

    PubMed Central

    Sammut, Michele; Cook, Steven J.; Nguyen, Ken C.Q.; Felton, Terry; Hall, David H.; Emmons, Scott W.

    2015-01-01

    Sex differences in behaviour extend to cognitive-like processes such as learning but the underlying dimorphisms in neural circuit development and organization that generate these behavioural differences are largely unknown. Here we define at the single-cell level, from development, through neural circuit connectivity, to function, the neural basis of a sex-specific learning in the nematode C. elegans. We show that sexual conditioning, a form of associative learning, requires a pair of male-specific interneurons whose progenitors are fully differentiated glia. These neurons are born during sexual maturation and incorporated into pre-exisiting sex-shared circuits to couple chemotactic responses to reproductive priorities. Our findings reveal a general role for glia as neural progenitors across metazoan taxa and demonstrate that the addition of sex-specific neuron types to brain circuits during sexual maturation is an important mechanism for the generation of sexually dimorphic plasticity in learning. PMID:26469050

  16. Glia-derived neurons are required for sex-specific learning in C. elegans.

    PubMed

    Sammut, Michele; Cook, Steven J; Nguyen, Ken C Q; Felton, Terry; Hall, David H; Emmons, Scott W; Poole, Richard J; Barrios, Arantza

    2015-10-15

    Sex differences in behaviour extend to cognitive-like processes such as learning, but the underlying dimorphisms in neural circuit development and organization that generate these behavioural differences are largely unknown. Here we define at the single-cell level-from development, through neural circuit connectivity, to function-the neural basis of a sex-specific learning in the nematode Caenorhabditis elegans. We show that sexual conditioning, a form of associative learning, requires a pair of male-specific interneurons whose progenitors are fully differentiated glia. These neurons are generated during sexual maturation and incorporated into pre-exisiting sex-shared circuits to couple chemotactic responses to reproductive priorities. Our findings reveal a general role for glia as neural progenitors across metazoan taxa and demonstrate that the addition of sex-specific neuron types to brain circuits during sexual maturation is an important mechanism for the generation of sexually dimorphic plasticity in learning. PMID:26469050

  17. Sex-Typed Activities: Cause or Effect?

    ERIC Educational Resources Information Center

    Carpenter, C. Jan; Huston-Stein, Aletha

    Sex differences in activity selection or choice appear by age 12 or 18 months. These choices are one of the earliest indicators of sex differences in the behavior of young children. Differences in activity participation or toy choices are evident long before the emergence of sex differences in personality characteristics like passivity or…

  18. A sex-specific metabolite identified in a marine invertebrate utilizing phosphorus-31 nuclear magnetic resonance.

    PubMed

    Kleps, Robert A; Myers, Terrell C; Lipcius, Romuald N; Henderson, Thomas O

    2007-01-01

    Hormone level differences are generally accepted as the primary cause for sexual dimorphism in animal and human development. Levels of low molecular weight metabolites also differ between men and women in circulating amino acids, lipids and carbohydrates and within brain tissue. While investigating the metabolism of blue crab tissues using Phosphorus-31 Nuclear Magnetic Resonance, we discovered that only the male blue crab (Callinectes sapidus) contained a phosphorus compound with a chemical shift well separated from the expected phosphate compounds. Spectra obtained from male gills were readily differentiated from female gill spectra. Analysis from six years of data from male and female crabs documented that the sex-specificity of this metabolite was normal for this species. Microscopic analysis of male and female gills found no differences in their gill anatomy or the presence of parasites or bacteria that might produce this phosphorus compound. Analysis of a rare gynandromorph blue crab (laterally, half male and half female) proved that this sex-specificity was an intrinsic biochemical process and was not caused by any variations in the diet or habitat of male versus female crabs. The existence of a sex-specific metabolite is a previously unrecognized, but potentially significant biochemical phenomenon. An entire enzyme system has been synthesized and activated only in one sex. Unless blue crabs are a unique species, sex-specific metabolites are likely to be present in other animals. Would the presence or absence of a sex-specific metabolite affect an animal's development, anatomy and biochemistry? PMID:17712428

  19. The evolution of sex-specific grandparental harm.

    PubMed

    Rice, William R; Gavrilets, Sergey; Friberg, Urban

    2010-09-01

    Recent empirical studies indicate that grandparents favour some categories of grandchildren over others. Here, we expand the previous theoretical foundation for this finding and show that grandchild-harming phenotypes are predicted to evolve by 'sexually antagonistic zygotic drive (SA-zygotic drive) of the sex chromosomes'. We use the logic of Hamilton's rule to develop a new 'no-cost-to-self nepotism rule' that greatly simplifies the determination of the invasion criteria for mutations that cause grandparents to harm grandchildren. We use this theory to generate predictions that distinguish SA-zygotic drive from theory based solely on paternity assurance. The major diagnostic prediction is that grandmothers, and to a lesser degree grandfathers, will evolve grandson-harming phenotypes that reduce the level of sib competition experienced by their more closely related granddaughters, especially in their sons' families. This prediction is supported by data from recent studies showing (i) grandmothers invest more in granddaughters than grandsons, and counterintuitively, (ii) paternal grandmothers reduce the survival of their grandsons. We conclude that SA-zygotic drive is plausibly operating in humans via sexually antagonistic grandparental care. PMID:20427341

  20. Sex differences in psychological effects of exercise.

    PubMed

    Hülya Aşçı, F

    2009-08-01

    The purpose of this study was to investigate sex differences in psychological effects of exercise on university students. University students (73 female and 65 male) were randomly assigned to experimental and control groups by equating sex in each group. The experimental group participated in step dance sessions of 50 min per day, 3 days per week for 10 weeks with 60-80% of their heart rate reserves. Throughout the 10-week period, the lecture control group was told not to participate in any organized or structured exercise and participated in a lecture that was about the physiological and psychological benefits of exercise. Self-concept, belief in external control, and trait anxiety of the groups were measured before and after the exercise program. A significant improvement in the psychological variables after the exercise program and more improvement for female exercise participants were expected. Analysis revealed no significant initial differences in self-concept, belief in external control, and trait anxiety between the two groups or between males and females, other than family and moral/ethical self. Repeated measures analysis of variance revealed that exercise led to less belief in external control and significant improvement in physical self and identity dimensions of self-concept for the experimental group compared to the control group. However, there was no significant difference in trait anxiety between the two groups after exercise (p>.05). Analysis also revealed that changes in belief in external control, trait anxiety, and self-concept did not differ with regard to sex. Males and females showed no difference in their improvement on trait anxiety, belief in external control, and most dimensions of self-concept during the 10 weeks. Only changes in personal and physical self throughout 10-week period were different for males and females. Exerciser males improved their personal self and physical self scores more than female exercisers and male and female

  1. Reporting of Sex Effects by Systematic Reviews on Interventions for Depression, Diabetes, and Chronic Pain.

    PubMed

    Duan-Porter, Wei; Goldstein, Karen M; McDuffie, Jennifer R; Hughes, Jaime M; Clowse, Megan E B; Klap, Ruth S; Masilamani, Varsha; Allen LaPointe, Nancy M; Nagi, Avishek; Gierisch, Jennifer M; Williams, John W

    2016-08-01

    Systematic reviews (SRs) have the potential to contribute uniquely to the evaluation of sex and gender differences (termed "sex effects"). This article describes the reporting of sex effects by SRs on interventions for depression, type 2 diabetes mellitus, and chronic pain conditions (chronic low back pain, knee osteoarthritis, and fibromyalgia). It includes SRs published since 1 October 2009 that evaluate medications, behavioral interventions, exercise, quality improvement, and some condition-specific treatments. The reporting of sex effects by primary randomized, controlled trials is also examined. Of 313 eligible SRs (86 for depression, 159 for type 2 diabetes mellitus, and 68 for chronic pain), few (n = 29) reported sex effects. Most SRs reporting sex effects used metaregression, whereas 9 SRs used subgroup analysis or individual-patient data meta-analysis. The proportion of SRs reporting the sex distribution of primary studies varied from a low of 31% (n = 8) for low back pain to a high of 68% (n = 23) for fibromyalgia. Primary randomized, controlled trials also infrequently reported sex effects, and most lacked an adequate sample size to examine them. Therefore, all SRs should report the proportion of women enrolled in primary studies and evaluate sex effects using appropriate methods whenever power is adequate. PMID:27111355

  2. The Evolution of Sex-Specific Dominance in Response to Sexually Antagonistic Selection.

    PubMed

    Spencer, Hamish G; Priest, Nicholas K

    2016-05-01

    Arguments about the evolutionary modification of genetic dominance have a long history in genetics, dating back more than 100 years. Mathematical investigations have shown that modifiers of the level of dominance at the locus of interest can spread at a reasonable rate only if heterozygotes at that locus are common. One hitherto neglected scenario is that of sexually antagonistic selection, which not only is ubiquitous in sexual species but also can generate stable high frequencies of heterozygotes that would appear to facilitate the spread of such modifiers. Here we present a mathematical model that shows that sexually specific dominance modification is a potential outcome of sexually antagonistic selection. Our model predicts that loci with higher levels of sexual conflict should exhibit greater differentiation between males and females in levels of dominance and that the strength of antagonistic selection experienced by one sex should be proportional to the level of dominance modification. We show that evidence from the literature is consistent with these predictions but suggest that empiricists should be alert to the possibility of there being numerous cases of sex-specific dominance. Further, in order to determine the significance of sexual conflict in the evolution of dominance, we need improved measures of sexual conflict and better characterization of loci that modify dominance of genes with sexually antagonistic fitness effects. PMID:27104997

  3. No effect of sex steroids on compensatory muscle hypertrophy

    NASA Technical Reports Server (NTRS)

    Max, S. R.; Rance, N. E.

    1984-01-01

    The effects of orchiectomy and/or subcutaneously implanted testosterone propionate (TP) on the hypertrophic response of rat plantaris muscles to functional overload (induced by bilateral removal of gastrocnemius and soleus muscles) are investigated experimentally. Muscle wet weight, metabolic substrate oxidation, and cytosolic androgen-receptor binding are measured, and the results are presented in tables. Eight weeks after surgery, the plantaris muscle weight as a percentage of body weight is found to be about twice that in rats without muscle overload, regardless of the sex-hormone status. Overloading causes decreased ability to oxidize glucose and pyruvate, decreased succinate dehydrogenase specific activity, and no change in the ability to oxidize beta-hydroxybutyrate or in androgen-receptor binding. The oxidative response is unaffected by orchiectomy or TP or both. It is argued that the actions of sex hormones and functional overload are not synergistic.

  4. Sex hormones have pervasive effects on thymic epithelial cells

    PubMed Central

    Dumont-Lagacé, Maude; St-Pierre, Charles; Perreault, Claude

    2015-01-01

    The goal of our study was to evaluate at the systems-level, the effect of sex hormones on thymic epithelial cells (TECs). To this end, we sequenced the transcriptome of cortical and medullary TECs (cTECs and mTECs) from three groups of 6 month-old mice: males, females and males castrated at four weeks of age. In parallel, we analyzed variations in the size of TEC subsets in those three groups between 1 and 12 months of age. We report that sex hormones have pervasive effects on the transcriptome of TECs. These effects were exquisitely TEC-subset specific. Sexual dimorphism was particularly conspicuous in cTECs. Male cTECs displayed low proliferation rates that correlated with low expression of Foxn1 and its main targets. Furthermore, male cTECs expressed relatively low levels of genes instrumental in thymocyte expansion (e.g., Dll4) and positive selection (Psmb11 and Ctsl). Nevertheless, cTECs were more abundant in males than females. Accumulation of cTECs in males correlated with differential expression of genes regulating cell survival in cTECs and cell differentiation in mTECs. The sexual dimorphism of TECs highlighted here may be mechanistically linked to the well-recognized sex differences in susceptibility to infections and autoimmune diseases. PMID:26250469

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

    PubMed

    Ballot, Orlane; Joseph, Vincent; Soliz, Jorge

    2015-06-01

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

  6. 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

  7. The X awakens: multifactorial ramifications of sex-specific differences in HIV-1 infection.

    PubMed

    Hagen, Sven; Altfeld, Marcus

    2016-01-01

    Sex-specific differences have been described for a variety of infectious and autoimmune diseases. In HIV-1 infection women present with significantly lower viral loads during early infection, but during chronic infection women progress faster to AIDS for the same amount of viral replication. Recent studies have shown that sex differences during HIV-1 infection might also include the size of the latent viral reservoir, which represents a major obstacle towards a cure for HIV-1. Here we review different immunological and virological aspects that can be influenced by sex hormones and sex-specific genetic factors and their contribution to viral replication, as well as the creation and maintenance of the HIV-1 reservoir. PMID:27482439

  8. All giraffes have female-specific properties: influence of grammatical gender on deductive reasoning about sex-specific properties in German speakers.

    PubMed

    Imai, Mutsumi; Schalk, Lennart; Saalbach, Henrik; Okada, Hiroyuki

    2014-04-01

    Grammatical gender is independent of biological sex for the majority of animal names (e.g., any giraffe, be it male or female, is grammatically treated as feminine). However, there is apparent semantic motivation for grammatical gender classes, especially in mapping human terms to gender. This research investigated whether this motivation affects deductive inference in native German speakers. We compared German with Japanese speakers (a language without grammatical gender) when making inferences about sex-specific biological properties. We found that German speakers tended to erroneously draw inferences when the sex in the premise and grammatical gender of the target animal agreed. An over-generalization of the grammar-semantics mapping was found even when the sex of the target was explicitly indicated. However, these effects occurred only when gender-marking articles accompanied the nouns. These results suggest that German speakers project sex-specific biological properties onto gender-marking articles but not onto conceptual representations of animals per se. PMID:23957504

  9. Transposon insertions causing constitutive sex-lethal activity in Drosophila melanogaster affect Sxl sex-specific transcript splicing

    SciTech Connect

    Berstein, M.; Cline, T.W. |; Lersch, R.A.; Subrahmanyan, L.

    1995-02-01

    Sex-lethal (Sxl) gene products induce female development in Drosophila melanogaster and suppress the transcriptional hyperactivation of X-linked genes responsible for male X-chromosome dosage compensation. Control of Sxl functioning by the dose of X-chromosomes normally ensures that the female-specific functions of this developmental switch gene are only expressed in diplo-X individuals. Although the immediate effect of X-chromosome dose is on Sxl transcription, during most of the life cycle {open_quotes}on{close_quotes} vs. {open_quotes}off{close_quotes} reflects alternative Sxl RNA splicing, with the female (productive) splicing mode maintained by a positive feedback activity of SXL protein on Sxl pre-mRNA splicing. {open_quotes}Male-lethal{close_quotes} (Sxl{sup M}) gain-of-function alleles subvert Sxl control by X-chromosome dose, allowing female Sxl functions to be expressed independent of the positive regulators upstream of Sxl. As a consequence, Sxl{sup M} haplo-X animals (chromosomal males) die because of improper dosage compensation, and Sxl{sup m} chromosomal females survive the otherwise lethal effects of mutations in upstream positive regulators. Transcript analysis of double-mutant male-viable Sxl{sup M} derivatives in which the Sxl{sup M} insertion is cis to loss-of-function mutations, combined with other results reported here, indicates that the constitutive character of these Sxl{sup M} alleles is a consequence of an alteration of the structure of the pre-mRNA that allow some level of female splicing to occur even in the absence of functional SXL protein. Surprisingly, however, most of the constitutive character of Sxl{sup M} alleles appears to depend on the mutant alleles` responsiveness, perhaps greater than wild-type, to the autoregulatory splicing activity of the wild-type SXL proteins they produce. 47 refs., 10 figs., 4 tabs.

  10. Variations of CT-Based Trunk Muscle Attenuation by Age, Sex, and Specific Muscle

    PubMed Central

    Anderson, Dennis E.

    2013-01-01

    Background. Fat accumulation in muscle may contribute to age-related declines in muscle function and is indicated by reduced attenuation of x-rays by muscle tissue in computed tomography scans. Reduced trunk muscle attenuation is associated with poor physical function, low back pain, and increased hyperkyphosis in older adults. However, variations in trunk muscle attenuation with age, sex and between specific muscles have not been investigated. Methods. A cross-sectional examination of trunk muscle attenuation in computed tomography scans was performed in 60 younger (35–50 years) and 60 older (75–87 years) adults randomly selected from participants in the Framingham Heart Study Offspring and Third Generation Multidetector Computed Tomography Study. Computed tomography attenuation of 11 trunk muscles was measured at vertebral levels T8 and L3, and the effects of age, sex, and specific muscle on computed tomography attenuation of trunk muscles were determined. Results. Muscle attenuation varied by specific muscle (p < .001), was lower in older adults (p < .001), and was generally lower in women than in men (p < .001), although not in all muscles. Age-related differences in muscle attenuation varied with specific muscle (p < .001), with the largest age differences occurring in the paraspinal and abdominal muscles. Conclusions. Trunk muscle attenuation is lower in older adults than in younger adults in both women and men, but such age-related differences vary widely between muscle groups. The reasons that some muscles exhibit larger age-related differences in fat content than others should be further explored to better understand age-related changes in functional capacity and postural stability. PMID:22904095

  11. 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

  12. 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

  13. The effect of sex ratios on suicide.

    PubMed

    Kuroki, Masanori

    2014-12-01

    Whereas sex ratios are likely to affect the likelihood of marriage, how sex ratios affect health and survival is underexplored. This study uses suicide as a measure of mental health and examines how suicides are affected by sex ratios. As women tend to marry men older than themselves, shrinking populations will lead to higher sex ratios (i.e., higher proportions of men) in the marriage market. Using data from Japan, I find that high sex ratios, both early-life and current, are correlated with higher male suicide rates, whereas female suicide rates are generally not affected. The results of this study have important implications for public health in countries where imbalanced sex ratios are a concern. PMID:23943552

  14. Genome-wide association studies suggest sex-specific loci associated with abdominal and visceral fat

    PubMed Central

    Sung, Yun Ju; Pérusse, Louis; Sarzynski, Mark A.; Fornage, Myriam; Sidney, Steve; Sternfeld, Barbara; Rice, Treva; Terry, Gregg; Jacobs, David R.; Katzmarzyk, Peter; Curran, Joanne E; Carr, John Jeffrey; Blangero, John; Ghosh, Sujoy; Després, Jean-Pierre; Rankinen, Tuomo; Rao, D.C.; Bouchard, Claude

    2015-01-01

    Background To identify loci associated with abdominal fat and replicate prior findings, we performed genome-wide association (GWA) studies of abdominal fat traits: subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), total adipose tissue (TAT) and visceral to subcutaneous adipose tissue ratio (VSR). Subjects and Methods Sex-combined and sex-stratified analyses were performed on each trait with (TRAIT-BMI) or without (TRAIT) adjustment for BMI, and cohort-specific results were combined via a fixed effects meta-analysis. A total of 2,513 subjects of European descent were available for the discovery phase. For replication, 2,171 European Americans and 772 African Americans were available. Results A total of 52 SNPs encompassing 7 loci showed suggestive evidence of association (p < 1.0 × 10−6) with abdominal fat in the sex-combined analyses. The strongest evidence was found on chromosome 7p14.3 between a SNP near BBS9 gene and VAT (rs12374818; p= 1.10 × 10−7), an association that was replicated (p = 0.02). For the BMI-adjusted trait, the strongest evidence of association was found between a SNP near CYCSP30 and VAT-BMI (rs10506943; p= 2.42 × 10−7). Our sex-specific analyses identified one genome-wide significant (p < 5.0 × 10−8) locus for SAT in women with 11 SNPs encompassing the MLLT10, DNAJC1 and EBLN1 genes on chromosome 10p12.31 (p = 3.97 × 10−8 to 1.13 × 10−8). The THNSL2 gene previously associated with VAT in women was also replicated (p= 0.006). The six gene/loci showing the strongest evidence of association with VAT or VAT-BMI were interrogated for their functional links with obesity and inflammation using the Biograph knowledge-mining software. Genes showing the closest functional links with obesity and inflammation were ADCY8 and KCNK9, respectively. Conclusions Our results provide evidence for new loci influencing abdominal visceral (BBS9, ADCY8, KCNK9) and subcutaneous (MLLT10/DNAJC1/EBLN1) fat, and confirmed a locus (THNSL2

  15. Autocrine function of aldehyde dehydrogenase 1 as a determinant of diet- and sex-specific differences in visceral adiposity.

    PubMed

    Yasmeen, Rumana; Reichert, Barbara; Deiuliis, Jeffrey; Yang, Fangping; Lynch, Alisha; Meyers, Joseph; Sharlach, Molly; Shin, Sangsu; Volz, Katharina S; Green, Kari B; Lee, Kichoon; Alder, Hansjuerg; Duester, Gregg; Zechner, Rudolf; Rajagopalan, Sanjay; Ziouzenkova, Ouliana

    2013-01-01

    Mechanisms for sex- and depot-specific fat formation are unclear. We investigated the role of retinoic acid (RA) production by aldehyde dehydrogenase 1 (Aldh1a1, -a2, and -a3), the major RA-producing enzymes, on sex-specific fat depot formation. Female Aldh1a1(-/-) mice, but not males, were resistant to high-fat (HF) diet-induced visceral adipose formation, whereas subcutaneous fat was reduced similarly in both groups. Sexual dimorphism in visceral fat (VF) was attributable to elevated adipose triglyceride lipase (Atgl) protein expression localized in clusters of multilocular uncoupling protein 1 (Ucp1)-positive cells in female Aldh1a1(-/-) mice compared with males. Estrogen decreased Aldh1a3 expression, limiting conversion of retinaldehyde (Rald) to RA. Rald effectively induced Atgl levels via nongenomic mechanisms, demonstrating indirect regulation by estrogen. Experiments in transgenic mice expressing an RA receptor response element (RARE-lacZ) revealed HF diet-induced RARE activation in VF of females but not males. In humans, stromal cells isolated from VF of obese subjects also expressed higher levels of Aldh1 enzymes compared with lean subjects. Our data suggest that an HF diet mediates VF formation through a sex-specific autocrine Aldh1 switch, in which Rald-mediated lipolysis in Ucp1-positive visceral adipocytes is replaced by RA-mediated lipid accumulation. Our data suggest that Aldh1 is a potential target for sex-specific antiobesity therapy. PMID:22933113

  16. Olfactory subsystems in the honeybee: sensory supply and sex specificity.

    PubMed

    Kropf, Jan; Kelber, Christina; Bieringer, Kathrin; Rössler, Wolfgang

    2014-09-01

    The antennae of honeybee (Apis mellifera) workers and drones differ in various aspects. One striking difference is the presence of Sensilla basiconica in (female) workers and their absence in (male) drones. We investigate the axonal projection patterns of olfactory receptor neurons (ORNs) housed in S. basiconica in honeybee workers by using selective anterograde labeling with fluorescent tracers and confocal-microscopy analysis of axonal projections in antennal lobe glomeruli. Axons of S. basiconica-associated ORNs preferentially projected into a specific glomerular cluster in the antennal lobe, namely the sensory input-tract three (T3) cluster. T3-associated glomeruli had previously been shown to be innervated by uniglomerular projection (output) neurons of the medial antennal lobe tract (mALT). As the number of T3 glomeruli is reduced in drones, we wished to determine whether this was associated with the reduction of glomeruli innervated by medial-tract projection neurons. We retrogradely traced mALT projection neurons in drones and counted the innervated glomeruli. The number of mALT-associated glomeruli was strongly reduced in drones compared with workers. The preferential projections of S. basiconica-associated ORNs in T3 glomeruli together with the reduction of mALT-associated glomeruli support the presence of a female (worker)-specific olfactory subsystem that is partly innervated by ORNs from S. basiconica and is associated with the T3 cluster of glomeruli and mALT projection neurons. We propose that this olfactory subsystem supports parallel olfactory processing related to worker-specific olfactory tasks such as the coding of colony odors, colony pheromones and/or odorants associated with foraging on floral resources. PMID:24817103

  17. Variance in age-specific sex composition of Pacific halibut catches, and comparison of statistical and genetic methods for reconstructing sex ratios

    NASA Astrophysics Data System (ADS)

    Loher, Timothy; Woods, Monica A.; Jimenez-Hidalgo, Isadora; Hauser, Lorenz

    2016-01-01

    Declines in size at age of Pacific halibut Hippoglossus stenolepis, in concert with sexually-dimorphic growth and a constant minimum commercial size limit, have led to the expectation that the sex composition of commercial catches should be increasingly female-biased. Sensitivity analyses suggest that variance in sex composition of landings may be the most influential source of uncertainty affecting current understanding of spawning stock biomass. However, there is no reliable way to determine sex at landing because all halibut are eviscerated at sea. In 2014, a statistical method based on survey data was developed to estimate the probability that fish of any given length at age (LAA) would be female, derived from the fundamental observation that large, young fish are likely female whereas small, old fish have a high probability of being male. Here, we examine variability in age-specific sex composition using at-sea commercial and closed-season survey catches, and compare the accuracy of the survey-based LAA technique to genetic markers for reconstructing the sex composition of catches. Sexing by LAA performed best for summer-collected samples, consistent with the hypothesis that the ability to characterize catches can be influenced by seasonal demographic shifts. Additionally, differences between survey and commercial selectivity that allow fishers to harvest larger fish within cohorts may generate important mismatch between survey and commercial datasets. Length-at-age-based estimates ranged from 4.7% underestimation of female proportion to 12.0% overestimation, with mean error of 5.8 ± 1.5%. Ratios determined by genetics were closer to true sample proportions and displayed less variability; estimation to within < 1% of true ratios was limited to genetics. Genetic estimation of female proportions ranged from 4.9% underestimation to 2.5% overestimation, with a mean absolute error of 1.2 ± 1.2%. Males were generally more difficult to assign than females: 6.7% of

  18. 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

  19. 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

  20. Host responses to the pathogen Mycobacterium avium subsp. paratuberculosis and beneficial microbes exhibit host sex specificity.

    PubMed

    Karunasena, Enusha; McMahon, K Wyatt; Chang, David; Brashears, Mindy M

    2014-08-01

    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) betweenthe sexes included interleukin-1α/β (IL-1α/β), IL-17, IL-6, IL-10, IL-12, and gamma interferon (IFN-) 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

  1. Sex-Specific Differences in Pathogen Susceptibility in Honey Bees (Apis mellifera)

    PubMed Central

    Retschnig, Gina; Williams, Geoffrey R.; Mehmann, Marion M.; Yañez, Orlando; de Miranda, Joachim R.; Neumann, Peter

    2014-01-01

    Sex-related differences in susceptibility to pathogens are a common phenomenon in animals. In the eusocial Hymenoptera the two female castes, workers and queens, are diploid and males are haploid. The haploid susceptibility hypothesis predicts that haploid males are more susceptible to pathogen infections compared to females. Here we test this hypothesis using adult male (drone) and female (worker) honey bees (Apis mellifera), inoculated with the gut endoparasite Nosema ceranae and/or black queen cell virus (BQCV). These pathogens were chosen due to previously reported synergistic interactions between Nosema apis and BQCV. Our data do not support synergistic interactions between N. ceranae and BQCV and also suggest that BQCV has limited effect on both drone and worker health, regardless of the infection level. However, the data clearly show that, despite lower levels of N. ceranae spores in drones than in workers, Nosema-infected drones had both a higher mortality and a lower body mass than non-infected drones, across all treatment groups, while the mortality and body mass of worker bees were largely unaffected by N. ceranae infection, suggesting that drones are more susceptible to this pathogen than workers. In conclusion, the data reveal considerable sex-specific differences in pathogen susceptibility in honey bees and highlight the importance of ultimate measures for determining susceptibility, such as mortality and body quality, rather than mere infection levels. PMID:24465518

  2. Sex-specific differences in pathogen susceptibility in honey bees (Apis mellifera).

    PubMed

    Retschnig, Gina; Williams, Geoffrey R; Mehmann, Marion M; Yañez, Orlando; de Miranda, Joachim R; Neumann, Peter

    2014-01-01

    Sex-related differences in susceptibility to pathogens are a common phenomenon in animals. In the eusocial Hymenoptera the two female castes, workers and queens, are diploid and males are haploid. The haploid susceptibility hypothesis predicts that haploid males are more susceptible to pathogen infections compared to females. Here we test this hypothesis using adult male (drone) and female (worker) honey bees (Apis mellifera), inoculated with the gut endoparasite Nosema ceranae and/or black queen cell virus (BQCV). These pathogens were chosen due to previously reported synergistic interactions between Nosema apis and BQCV. Our data do not support synergistic interactions between N. ceranae and BQCV and also suggest that BQCV has limited effect on both drone and worker health, regardless of the infection level. However, the data clearly show that, despite lower levels of N. ceranae spores in drones than in workers, Nosema-infected drones had both a higher mortality and a lower body mass than non-infected drones, across all treatment groups, while the mortality and body mass of worker bees were largely unaffected by N. ceranae infection, suggesting that drones are more susceptible to this pathogen than workers. In conclusion, the data reveal considerable sex-specific differences in pathogen susceptibility in honey bees and highlight the importance of ultimate measures for determining susceptibility, such as mortality and body quality, rather than mere infection levels. PMID:24465518

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

    PubMed

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

    2015-12-01

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

  4. Sex-specific quantitative trait loci govern susceptibility to Theiler's murine encephalomyelitis virus-induced demyelination.

    PubMed Central

    Butterfield, Russell J; Roper, Randall J; Rhein, Dominic M; Melvold, Roger W; Haynes, Lia; Ma, Runlin Z; Doerge, R W; Teuscher, Cory

    2003-01-01

    Susceptibility to Theiler's murine encephalomyelitis virus-induced demyelination (TMEVD), a mouse model for multiple sclerosis (MS), is genetically controlled. Through a mouse-human comparative mapping approach, identification of candidate susceptibility loci for MS based on the location of TMEVD susceptibility loci may be possible. Composite interval mapping (CIM) identified quantitative trait loci (QTL) controlling TMEVD severity in male and female backcross populations derived from susceptible DBA/2J and resistant BALBc/ByJ mice. We report QTL on chromosomes 1, 5, 15, and 16 affecting male mice. In addition, we identified two QTL in female mice located on chromosome 1. Our results support the existence of three linked sex-specific QTL on chromosome 1 with opposing effects on the severity of the clinical signs of TMEV-induced disease in male and female mice. PMID:12663542

  5. Sex-specific daily spawning seaward migration of striped mullet Mugil cephalus in a coastal lagoon.

    PubMed

    Katselis, G; Koukou, K; Ramfos, A; Moutopoulos, D K

    2015-08-01

    The sex-specific daily spawning seaward migration of striped mullet Mugil cephalus was analysed in Palaiopotamos Lagoon (western Greek coast, eastern Mediterranean Sea) in an 86 day time series. The data set included the daily number of M. cephalus catches in barrier traps, as well as a time series of some weather variables. The analysis revealed an important linkage of the daily migration rate as well as a sex-specific response of the species to the lunar cycle and the short-term fluctuation of weather variables. The daily migration pattern of females was more persistent than that of males, indicating a possible female leadership role during the spawning migration. Multiregression models described quite accurately the sex-specific daily migration rates of the species, thus providing a potentially powerful tool regarding the lagoon fishery management of M. cephalus, especially in the context of climate change. PMID:26108151

  6. Transgene-based, female-specific lethality system for genetic sexing of the silkworm, Bombyx mori

    PubMed Central

    Tan, Anjiang; Fu, Guoliang; Jin, Li; Guo, Qiuhong; Li, Zhiqian; Niu, Baolong; Meng, Zhiqi; Morrison, Neil I.; Alphey, Luke; Huang, Yongping

    2013-01-01

    Transgene-based genetic sexing methods are being developed for insects of agricultural and public health importance. Male-only rearing has long been sought in sericulture because males show superior economic characteristics, such as better fitness, lower food consumption, and higher silk yield. Here we report the establishment of a transgene-based genetic sexing system for the silkworm, Bombyx mori. We developed a construct in which a positive feedback loop regulated by sex-specific alternative splicing leads to high-level expression of the tetracycline-repressible transactivator in females only. Transgenic animals show female-specific lethality during embryonic and early larval stages, leading to male-only cocoons. This transgene-based female-specific lethal system not only has wide application in sericulture, but also has great potential in lepidopteran pest control. PMID:23569267

  7. Sex Stereotype Effects in Children's Picture Recognition.

    ERIC Educational Resources Information Center

    Cann, Arnie; Newbern, Sara R.

    1984-01-01

    Reports an experiment in which 80 male and female six and eight year olds were presented with pictures consistent or inconsistent with sex stereotypes and pictures of neutral activities. Later, subjects performed a picture-recognition task. Among the variables investigated were subjects' labeling of pictures and sex-stereotype consistency. (CB)

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

    SciTech Connect

    Lingappan, Krithika; Jiang, Weiwu; Wang, Lihua; Couroucli, Xanthi I.; Barrios, Roberto; Moorthy, Bhagavatula

    2013-10-15

    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 expression 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.

  9. Seasonal Variation in Parental Care Drives Sex-Specific Foraging by a Monomorphic Seabird

    PubMed Central

    Burke, Chantelle M.; Montevecchi, William A.; Regular, Paul M.

    2015-01-01

    Evidence of sex-specific foraging in monomorphic seabirds is increasing though the underlying mechanisms remain poorly understood. We investigate differential parental care as a mechanism for sex-specific foraging in monomorphic Common Murres (Uria aalge), where the male parent alone provisions the chick after colony departure. Using a combination of geolocation-immersion loggers and stable isotopes, we assess two hypotheses: the reproductive role specialization hypothesis and the energetic constraint hypothesis. We compare the foraging behavior of females (n = 15) and males (n = 9) during bi-parental at the colony, post-fledging male-only parental care and winter when parental care is absent. As predicted by the reproductive role specialization hypothesis, we found evidence of sex-specific foraging during post-fledging only, the stage with the greatest divergence in parental care roles. Single-parenting males spent almost twice as much time diving per day and foraged at lower quality prey patches relative to independent females. This implies a potential energetic constraint for males during the estimated 62.8 ± 8.9 days of offspring dependence at sea. Contrary to the predictions of the energetic constraint hypothesis, we found no evidence of sex-specific foraging during biparental care, suggesting that male parents did not forage for their own benefit before colony departure in anticipation of post-fledging energy constraints. We hypothesize that unpredictable prey conditions at Newfoundland colonies in recent years may limit male parental ability to allocate additional time and energy to self-feeding during biparental care, without compromising chick survival. Our findings support differential parental care as a mechanism for sex-specific foraging in monomorphic murres, and highlight the need to consider ecological context in the interpretation of sex-specific foraging behavior. PMID:26575646

  10. COMT-by-Sex Interaction Effect on Psychosis Proneness

    PubMed Central

    de Castro-Catala, Marta; Barrantes-Vidal, Neus; Sheinbaum, Tamara; Moreno-Fortuny, Artal; Kwapil, Thomas R.; Rosa, Araceli

    2015-01-01

    Schizotypy phenotypes in the general population share etiopathogenic mechanisms and risk factors with schizophrenia, supporting the notion of psychosis as a continuum ranging from nonclinical to clinical deviance. Catechol-O-methyltransferase (COMT) is a candidate susceptibility gene for schizophrenia that is involved in the regulation of dopamine in the prefrontal cortex. Several recent studies have reported a sex difference in the impact of COMT genotype on psychiatric and cognitive phenotypes and personality traits. The present study investigated the association of COMT Val158Met (rs4680) with psychometric positive and negative schizotypy and psychotic experiences in a sample of 808 nonclinical young adults. The main finding was that sex moderates the association of COMT genotype with the negative dimension of both schizotypy and psychotic experiences. Male subjects carrying the Val allele tended to score higher on the negative dimension of both trait and symptom-like measures. The results from the present study are consistent with recent work suggesting an association between negative schizotypy and diminished prefrontal dopamine availability. They support the idea that a biological differentiation underlies the positive and negative schizotypy dimensions. Additionally, these findings contribute to the growing literature on sex-specific effects of COMT on the predisposition to psychiatric disorders and personality traits. PMID:25722988

  11. Sex-specific age-related changes of information processing rate indicators during childhood and adolescence.

    PubMed

    Zebec, Mislav S; Budimir, Sanja; Merkas, Marina; Szirovicza, Lajos; Zivicnjak, Miroslav

    2014-06-01

    Despite the relevant findings on non-average information processing rate (IPR) indicators-intelligence relation, and on age-related changes of some of these indicators during aging, the research on sex-specific age-related changes of these indicators during childhood and adolescence are lacking. In a transversal study, 1197 school children (598 girls) aged 8-18 have been individually measured on 5 IPR indicators--two averages (mean_t, median_t) and three non-averages (min_t, max_t, sd_t). The results corroborated the expected non-linear changes of average IPR indicators in the observed developmental period, whereby the sex difference in related developmental patterns was detected: marked age-related decrement in girls ceased at the age of 12, and in boys around the age of 13-14, after which progress in both sexes gradually ceased by the age of 18 and was less pronounced in girls. Generally similar non-linear age-related decrements of non-average indicators were registered, but they showed mutual intensity differences at specific ages and sex difference in developmental patterns was detected, analogously to average indicators. Systematic sex differences in the whole observed period were obtained only in two non-average indicators: girls showed minor sd_t and boys showed minor min_t. In specific age groups, a number of sex differences were obtained that are explainable by two possible mechanisms: earlier maturation in girls and sex bias of the IPR task content. The justifiability of separate, average and non-average, IPR indicators application was corroborated by their distribution form differences, by mutual, predominantly low and medium correlations, by the different intensity of their developmental changes and by their different ability to detect sex differences. For all registered phenomena, the theoretical and/or empirical explanations were offered from the domain of sex specific intellectual, motor and neural development, and it has been shown that non

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

    PubMed Central

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

    2014-01-01

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

  13. Homozygosity by descent mapping of blood pressure in the Old Order Amish: evidence for sex specific genetic architecture

    PubMed Central

    McArdle, Patrick F; Dytch, Harvey; O'Connell, Jeffery R; Shuldiner, Alan R; Mitchell, Braxton D; Abney, Mark

    2007-01-01

    Background High blood pressure is a well established risk factor for morbidity and mortality acting through heart disease, stroke and cardiovascular disease. Genome wide scans have linked regions of nearly every human chromosome to blood pressure related traits. We have capitalized on beneficial qualities of the Old Order Amish of Lancaster, PA, a closed founder population with a relatively small number of founders, to perform a genome wide homozygosity by descent mapping scan. Each individual in the study has a non zero probability of consanguinity. Systolic and diastolic blood pressures are shown to have appreciable dominance variance components. Results Areas of two chromosomes were identified as suggestive of linkage to SBP and 5 areas to DBP in either the overall or sex specific analyses. The strongest evidence for linkage in the overall sample was to Chromosome 18q12 (LOD = 2.6 DBP). Sex specific analyses identified a linkage on Chromosome 4p12-14 (LOD in men only = 3.4 SBP). At Chromosome 2q32-33, an area where we previously reported significant evidence for linkage to DBP using a conventional identity by descent approach, the LOD was 1.4; however an appreciable sex effect was observed with men accounting for most of the linkage (LOD in men only = 2.6). Conclusion These results add evidence to a sex specific genetic architecture to blood pressure related traits, particularly in regions of linkage on chromosome 2, 4 and 18. PMID:17908314

  14. An Allometric Analysis of Sex and Sex Chromosome Dosage Effects on Subcortical Anatomy in Humans.

    PubMed

    Reardon, Paul Kirkpatrick; Clasen, Liv; Giedd, Jay N; Blumenthal, Jonathan; Lerch, Jason P; Chakravarty, M Mallar; Raznahan, Armin

    2016-02-24

    Structural neuroimaging of humans with typical and atypical sex-chromosome complements has established the marked influence of both Yand X-/Y-chromosome dosage on total brain volume (TBV) and identified potential cortical substrates for the psychiatric phenotypes associated with sex-chromosome aneuploidy (SCA). Here, in a cohort of 354 humans with varying karyotypes (XX, XY, XXX, XXY, XYY, XXYY, XXXXY), we investigate sex and SCA effects on subcortical size and shape; focusing on the striatum, pallidum and thalamus. We find large effect-size differences in the volume and shape of all three structures as a function of sex and SCA. We correct for TBV effects with a novel allometric method harnessing normative scaling rules for subcortical size and shape in humans, which we derive here for the first time. We show that all three subcortical volumes scale sublinearly with TBV among healthy humans, mirroring known relationships between subcortical volume and TBV among species. Traditional TBV correction methods assume linear scaling and can therefore invert or exaggerate sex and SCA effects on subcortical anatomy. Allometric analysis restricts sex-differences to: (1) greater pallidal volume (PV) in males, and (2) relative caudate head expansion and ventral striatum contraction in females. Allometric analysis of SCA reveals that supernumerary X- and Y-chromosomes both cause disproportionate reductions in PV, and coordinated deformations of striatopallidal shape. Our study provides a novel understanding of sex and sex-chromosome dosage effects on subcortical organization, using an allometric approach that can be generalized to other basic and clinical structural neuroimaging settings. PMID:26911691

  15. [Determination of fetal sex by amplification of Y-chromosome-specific DNA].

    PubMed

    Huang, S Z

    1989-08-01

    This paper describes a rapid and highly sensitive method for determination of fetal sex. Y-chromosome-specific sequences as well as Alu-specific sequences were amplified with polymerase chain reaction (PCR). Then fetal sex was determined by comparison of the two amplified DNA sequences. Polymerase chain reaction can be performed on lysed amniotic fluid cells or chorionic villus samples or dried blood spots on filter paper blot without prior DNA extraction. The analysis of the amplified DNA was performed immediately by agarose gel electrophoresis without DNA hybridization with radioactive probe. By using this method, determination of sex was performed on 3 fetuses at risk for DMD, and on 2 fetuses at risk for hemophilia, prenatal detection was confirmed by examination of the neonates. PMID:2620273

  16. Rapid and early determination of sex using trophoblast biopsy specimens and Y chromosome specific DNA probes.

    PubMed

    Vergnaud, G; Kaplan, L; Weissenbach, J; Dumez, Y; Berger, R; Tiollais, P; Guellaen, G

    1984-07-14

    The feasibility of determining sex by analysing deoxyribonucleic acid (DNA) with two probes specific for Y chromosomes was shown using DNA obtained from samples of blood from 30 non-related males and females of different ethnic origin. The DNA was spotted on nitrocellulose filters and hybridised with both a repetitive (P1) and a unique (49f) sequence specific for the human Y chromosome. A strong positive signal with both probes indicated the presence of male DNA. The sex of 12 fetuses was then similarly determined by molecular characterisation of DNA from trophoblast biopsy specimens. Chorionic samples were obtained in seven cases before termination of pregnancy in the first trimester and the aborted embryos subjected to karyotyping and sex chromatin analysis. In the five other cases samples were obtained from placentas obtained during caesarean section. Results of hybridisation were compared with those from cytogenic studies and actual sex at birth. The sex of all 12 fetuses was determined correctly by hybridisation. PMID:6428684

  17. Sex-specific hemispheric differences in cortical activation to a bimodal odor.

    PubMed

    Lundström, Johan N; Hummel, Thomas

    2006-01-30

    Most odorants we experience in every day life are bimodal in that they activate both the main olfactory and the intranasal trigeminal system. Few studies have investigated whether true bimodal odorants are processed differently than unimodal odorants. The aim of the study was to address sex-dependent hemispheric differences in olfactory event-related potentials. Event-related potentials (ERP) of the bimodal stimulant peppermint oil were recorded in 34 healthy subjects (17 women). No sex-related differences in olfactory sensitivity, trigeminal sensitivity or hedonic ratings of the stimuli were found. Although perceived similarly by men and women, results indicated a sex-differentiated hemispheric response to bimodal odors. Women generally expressed larger amplitudes and longer latencies over their left hemisphere, whereas men demonstrated a similar pattern over their right hemisphere. This effect was most evident for the early sensory derived ERP components indicating a sex-dependent difference in the sensory processing of bimodal odors. PMID:16183142

  18. Sex Pheromone Receptor Specificity in the European Corn Borer Moth, Ostrinia nubilalis.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The European corn borer (ECB), Ostrinia nubilalis, exists as two separate sex pheromone races. ECB(Z) females produce a 97:3 blend of Z11- and E11-14:OAc whereas ECB(E) females produce an opposite 1:99 ratio of the Z and E isomers. Males of each race respond specifically to their conspecific female...

  19. Local and neighboring patch conditions alter sex-specific movement in banana weevils.

    PubMed

    Carval, Dominique; Perrin, Benjamin; Duyck, Pierre-François; Tixier, Philippe

    2015-12-01

    Understanding the mechanisms underlying the movements and spread of a species over time and space is a major concern of ecology. Here, we assessed the effects of an individual's sex and the density and sex ratio of conspecifics in the local and neighboring environment on the movement probability of the banana weevil, Cosmopolites sordidus. In a "two patches" experiment, we used radiofrequency identification tags to study the C. sordidus movement response to patch conditions. We showed that local and neighboring densities of conspecifics affect the movement rates of individuals but that the density-dependent effect can be either positive or negative depending on the relative densities of conspecifics in local and neighboring patches. We demonstrated that sex ratio also influences the movement of C. sordidus, that is, the weevil exhibits nonfixed sex-biased movement strategies. Sex-biased movement may be the consequence of intrasexual competition for resources (i.e., oviposition sites) in females and for mates in males. We also detected a high individual variability in the propensity to move. Finally, we discuss the role of demographic stochasticity, sex-biased movement, and individual heterogeneity in movement on the colonization process. PMID:27069621

  20. Sex-specific disruption of murine midbrain astrocytic and dopaminergic developmental trajectories following antenatal GC treatment.

    PubMed

    McArthur, Simon; Pienaar, Ilse S; Siddiqi, Sindhu M; Gillies, Glenda E

    2016-06-01

    The mammalian midbrain dopaminergic systems arising in the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) are critical for coping behaviours and are implicated in neuropsychiatric disorders where early life challenges comprise significant risk factors. Here, we aimed to advance our hypothesis that glucocorticoids (GCs), recognised key players in neurobiological programming, target development within these systems, with a novel focus on the astrocytic population. Mice received antenatal GC treatment (AGT) by including the synthetic GC, dexamethasone, in the mothers' drinking water on gestational days 16-19; controls received normal drinking water. Analyses of regional shapes and volumes of the adult SNc and VTA demonstrated that AGT induced long-term, dose-dependent, structural changes that were accompanied by profound effects on astrocytes (doubling/tripling of numbers and/or density). Additionally, AGT induced long-term changes in the population size and distribution of SNc/VTA dopaminergic neurons, confirming and extending our previous observations made in rats. Furthermore, glial/neuronal structural remodelling was sexually dimorphic and depended on the AGT dose and sub-region of the SNc/VTA. Investigations within the neonatal brain revealed that these long-term organisational effects of AGT depend, at least in part, on targeting perinatal processes that determine astrocyte density and programmed cell death in dopaminergic neurons. Collectively, our characterisation of enduring, AGT-induced, sex-specific cytoarchitectural disturbances suggests novel mechanistic links for the strong association between early environmental challenge (inappropriate exposure to excess GCs) and vulnerability to developing aberrant behaviours in later life, with translational implications for dopamine-associated disorders (such as schizophrenia, ADHD, autism, depression), which typically show a sex bias. PMID:25944572

  1. 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. PMID:27028080

  2. Evolution of sexes from an ancestral mating-type specification pathway.

    PubMed

    Geng, Sa; De Hoff, Peter; Umen, James G

    2014-07-01

    Male and female sexes have evolved repeatedly in eukaryotes but the origins of dimorphic sexes and their relationship to mating types in unicellular species are not understood. Volvocine algae include isogamous species such as Chlamydomonas reinhardtii, with two equal-sized mating types, and oogamous multicellular species such as Volvox carteri with sperm-producing males and egg-producing females. Theoretical work predicts genetic linkage of a gamete cell-size regulatory gene(s) to an ancestral mating-type locus as a possible step in the evolution of dimorphic gametes, but this idea has not been tested. Here we show that, contrary to predictions, a single conserved mating locus (MT) gene in volvocine algae-MID, which encodes a RWP-RK domain transcription factor-evolved from its ancestral role in C. reinhardtii as a mating-type specifier, to become a determinant of sperm and egg development in V. carteri. Transgenic female V. carteri expressing male MID produced functional sperm packets during sexual development. Transgenic male V. carteri with RNA interference (RNAi)-mediated knockdowns of VcMID produced functional eggs, or self-fertile hermaphrodites. Post-transcriptional controls were found to regulate cell-type-limited expression and nuclear localization of VcMid protein that restricted its activity to nuclei of developing male germ cells and sperm. Crosses with sex-reversed strains uncoupled sex determination from sex chromosome identity and revealed gender-specific roles for male and female mating locus genes in sexual development, gamete fitness and reproductive success. Our data show genetic continuity between the mating-type specification and sex determination pathways of volvocine algae, and reveal evidence for gender-specific adaptations in the male and female mating locus haplotypes of Volvox. These findings will enable a deeper understanding of how a master regulator of mating-type determination in an ancestral unicellular species was reprogrammed to

  3. Evolution of Sexes from an Ancestral Mating-Type Specification Pathway

    PubMed Central

    Geng, Sa; De Hoff, Peter; Umen, James G.

    2014-01-01

    Male and female sexes have evolved repeatedly in eukaryotes but the origins of dimorphic sexes and their relationship to mating types in unicellular species are not understood. Volvocine algae include isogamous species such as Chlamydomonas reinhardtii, with two equal-sized mating types, and oogamous multicellular species such as Volvox carteri with sperm-producing males and egg-producing females. Theoretical work predicts genetic linkage of a gamete cell-size regulatory gene(s) to an ancestral mating-type locus as a possible step in the evolution of dimorphic gametes, but this idea has not been tested. Here we show that, contrary to predictions, a single conserved mating locus (MT) gene in volvocine algae—MID, which encodes a RWP-RK domain transcription factor—evolved from its ancestral role in C. reinhardtii as a mating-type specifier, to become a determinant of sperm and egg development in V. carteri. Transgenic female V. carteri expressing male MID produced functional sperm packets during sexual development. Transgenic male V. carteri with RNA interference (RNAi)-mediated knockdowns of VcMID produced functional eggs, or self-fertile hermaphrodites. Post-transcriptional controls were found to regulate cell-type–limited expression and nuclear localization of VcMid protein that restricted its activity to nuclei of developing male germ cells and sperm. Crosses with sex-reversed strains uncoupled sex determination from sex chromosome identity and revealed gender-specific roles for male and female mating locus genes in sexual development, gamete fitness and reproductive success. Our data show genetic continuity between the mating-type specification and sex determination pathways of volvocine algae, and reveal evidence for gender-specific adaptations in the male and female mating locus haplotypes of Volvox. These findings will enable a deeper understanding of how a master regulator of mating-type determination in an ancestral unicellular species was reprogrammed

  4. Sex-specific Differences in Hyperoxic Lung Injury in Mice: Implications for Acute and Chronic Lung Disease in Humans

    PubMed Central

    Lingappan, Krithika; Jiang, Weiwu; Wang, Lihua; Couroucli, Xanthi I.; Barrios, Roberto; Moorthy, Bhagavatula

    2014-01-01

    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 (FiO2>0.95). After exposure to hyperoxia, lung injury, levels of 8-iso-prostaglandin F2 alpha (8-iso-PGF 2α) (LC-MS/MS), apoptosis (TUNEL) and inflammatory markers (suspension bead array) were determined. CytochromeP450 (CYP)1A expression 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. PMID:23792423

  5. Sex-specific associations between birth weight and adult primary liver cancer in a large cohort of Danish children.

    PubMed

    Zimmermann, Esther; Berentzen, Tina L; Gamborg, Michael; Sørensen, Thorkild I A; Baker, Jennifer L

    2016-03-15

    Whether the prenatal period is critical for the development of adult primary liver cancer (PLC) is sparsely investigated. Recently, attention has been drawn to potential sex-differences in the early origins of adult disease. The association between birth weight and adult PLC, separately in men and women was investigated, using a large cohort of 217,227 children (51% boys), born from 1936 to 1980, from the Copenhagen School Health Records Register, and followed them until 2010 in national registers. Hazard ratios (95% confidence intervals) of PLC (30 years or older) were estimated by Cox regression models stratified by birth cohort. During 5.1 million person-years of follow-up, 185 men and 65 women developed PLC. Sex modified the association between birth weight and adult PLC (p values for interaction = 0.0005). Compared with a sex-specific reference group of birth weights between 3.25 and 3.75 kg, men with birth weights between 2.00 and 3.25 kg and 3.75-5.50 kg, had HRs of 1.48 (1.06-2.05) and 0.85 (0.56-1.28), respectively. Among women the corresponding HRs were 1.71 (0.90-3.29) and 3.43 (1.73-6.82). Associations were similar for hepatocellular carcinoma only, across year of birth, and after accounting for diagnoses of alcohol-related disorders, viral hepatitis and biliary cirrhosis. Prenatal exposures influenced the risk of adult PLC, and the effects at the high birth weight levels appeared to be sex-specific. These findings underscore the importance of considering sex-specific mechanisms in the early origins of adult PLC. PMID:26506514

  6. The impact of childhood abuse on inpatient substance users: specific links with risky sex, aggression, and emotion dysregulation.

    PubMed

    Banducci, Anne N; Hoffman, Elana M; Lejuez, C W; Koenen, Karestan C

    2014-05-01

    Adults with substance use disorders (SUDs) report a high prevalence of childhood abuse. Research in the general population suggests specific types of abuse lead to particular negative outcomes; it is not known whether this pattern holds for adults with SUDs. We hypothesized that specific types of abuse would be associated with particular behavioral and emotional outcomes among substance users. That is, childhood sexual abuse would be associated with risky sex behaviors, childhood physical abuse with aggression, and childhood emotional abuse with emotion dysregulation. 280 inpatients (M age=43.3; 69.7% male; 88.4% African American) in substance use treatment completed the Childhood Trauma Questionnaire (CTQ), HIV Risk-Taking Behavior Scale, Addiction Severity Index, Difficulties with Emotion Regulation Scale (DERS), Distress Tolerance Scale (DTS), and Affect Intensity and Dimensions of Affiliation Motivation (AIM). Consistent with our hypotheses, the CTQ sexual abuse subscale uniquely predicted exchanging sex for cocaine and heroin, number of arrests for prostitution, engaging in unprotected sex with a casual partner during the prior year, and experiencing low sexual arousal when sober. The physical abuse subscale uniquely predicted number of arrests for assault and weapons offenses. The emotional abuse subscale uniquely predicted the DERS total score, AIM score, and DTS score. Among substance users, different types of abuse are uniquely associated with specific negative effects. Assessment of specific abuse types among substance users may be informative in treatment planning and relapse prevention. PMID:24521524

  7. Sniffing human sex-steroid derived compounds modulates mood, memory and autonomic nervous system function in specific behavioral contexts.

    PubMed

    Bensafi, M; Brown, W M; Khan, R; Levenson, B; Sobel, N

    2004-06-01

    We asked whether the effects of exposure to two human sex-steroid derived compounds were context dependent. The effects of sniffing 4,16-androstadien-3-one (AND) and 1,3,5(10),16-estratetraen-3-ol (EST) on mood, memory, and autonomic nervous system responses were explored in 72 participants. Subjects were tested with AND, EST, or a Control compound within four mood contexts: neutral, sexually aroused, sad and happy. These moods were successfully induced using selected film segments (P < 0.0001). During the neutral context, none of the compounds affected mood or autonomic nervous system function. However, compound effects were significantly increased within arousing contexts. During the sexually arousing context, both compounds increased sexual arousal (P < 0.029). During the sad context, AND maintained positive mood in women (P< 0.050) and increased negative mood in men (P < 0.031). Memory for events during the sad context was impaired by AND in women (P < 0.047) but not in men. Finally, effects of AND on physiology were observed during the sexually arousing context whereby AND increased skin temperature in both sexes (P < 0.022) but reduced abdominal respiration rate in men only (P < 0.034). These results suggest that sex-steroidal compounds modulate mood, memory and autonomic nervous system responses and increase their significance within specific behavioral contexts. These findings lend support to a specific role for these compounds in chemical communication between humans. PMID:15135965

  8. Caste-Specific and Sex-Specific Expression of Chemoreceptor Genes in a Termite

    PubMed Central

    Mikheyev, Alexander; Tin, Mandy M. Y.; Watanabe, Yutaka; Matsuura, Kenji

    2016-01-01

    The sophisticated colony organization of eusocial insects is primarily maintained through the utilization of pheromones. The regulation of these complex social interactions requires intricate chemoreception systems. The recent publication of the genome of Zootermopsis nevadensis opened a new avenue to study molecular basis of termite caste systems. Although there has been a growing interest in the termite chemoreception system that regulates their sophisticated caste system, the relationship between division of labor and expression of chemoreceptor genes remains to be explored. Using high-throughput mRNA sequencing (RNA-seq), we found several chemoreceptors that are differentially expressed among castes and between sexes in a subterranean termite Reticulitermes speratus. In total, 53 chemoreception-related genes were annotated, including 22 odorant receptors, 7 gustatory receptors, 12 ionotropic receptors, 9 odorant-binding proteins, and 3 chemosensory proteins. Most of the chemoreception-related genes had caste-related and sex-related expression patterns; in particular, some chemoreception genes showed king-biased or queen-biased expression patterns. Moreover, more than half of the genes showed significant age-dependent differences in their expression in female and/or male reproductives. These results reveal a strong relationship between the evolution of the division of labor and the regulation of chemoreceptor gene expression, thereby demonstrating the chemical communication and underlining chemoreception mechanism in social insects. PMID:26760975

  9. Caste-Specific and Sex-Specific Expression of Chemoreceptor Genes in a Termite.

    PubMed

    Mitaka, Yuki; Kobayashi, Kazuya; Mikheyev, Alexander; Tin, Mandy M Y; Watanabe, Yutaka; Matsuura, Kenji

    2016-01-01

    The sophisticated colony organization of eusocial insects is primarily maintained through the utilization of pheromones. The regulation of these complex social interactions requires intricate chemoreception systems. The recent publication of the genome of Zootermopsis nevadensis opened a new avenue to study molecular basis of termite caste systems. Although there has been a growing interest in the termite chemoreception system that regulates their sophisticated caste system, the relationship between division of labor and expression of chemoreceptor genes remains to be explored. Using high-throughput mRNA sequencing (RNA-seq), we found several chemoreceptors that are differentially expressed among castes and between sexes in a subterranean termite Reticulitermes speratus. In total, 53 chemoreception-related genes were annotated, including 22 odorant receptors, 7 gustatory receptors, 12 ionotropic receptors, 9 odorant-binding proteins, and 3 chemosensory proteins. Most of the chemoreception-related genes had caste-related and sex-related expression patterns; in particular, some chemoreception genes showed king-biased or queen-biased expression patterns. Moreover, more than half of the genes showed significant age-dependent differences in their expression in female and/or male reproductives. These results reveal a strong relationship between the evolution of the division of labor and the regulation of chemoreceptor gene expression, thereby demonstrating the chemical communication and underlining chemoreception mechanism in social insects. PMID:26760975

  10. Investigating sex-specific dynamics using uniparental markers: West New Guinea as a case study

    PubMed Central

    Mona, Stefano; Mordret, Ernest; Veuille, Michel; Tommaseo-Ponzetta, Mila

    2013-01-01

    Abstract Mitochondrial DNA (mtDNA) and Y chromosome (NRY) genetic markers have been often contrasted to investigate sex-specific dynamics. Traditionally, isolation by distance, intrapopulation genetic diversity and population differentiation are estimated from both markers and compared. Two possible sources of bias are often neglected. First, kilometric distances are frequently used as predictor of the connectivity between groups, hiding the role played by environmental features at a microgeographic scale. Second, the comparison of intrapopulation diversity and population differentiation between mtDNA and NRY is hampered by their different mutational mechanisms and rates. Here, we show how to account for these biases by analyzing from a different perspective a published dataset of eight West New Guinea (WNG) populations for which mtDNA control region sequences and seven linked NRY microsatellites had been typed. First, we modeled the connectivity among sampled populations by computing the number of days required to travel between groups. Then, we investigated the differences between the two sexes accounting for the molecular characteristics of the markers examined to obtain estimates on the product of the effective population size and the migration rate among demes (Nm). We achieved this goal by studying the shape of the gene genealogy at several sampling levels and using spatial explicit simulations. Both the direction and the rate of migration differ between male and females, with an Nm estimated to be >6 times higher in the latter under many evolutionary scenarios. We finally highlight the importance of applying metapopulation models when analyzing the genetic diversity of a species. We have applied the prediction of the sampling theory in a meta-population and we have corroborated our finding using spatial explicit simulations. Both approaches are fundamentally meant to deal with structured populations: we strongly believe in the importance of tacking structure

  11. Sex- and Tissue-Specific Methylome Changes in Brains of Mice Perinatally Exposed to Lead

    PubMed Central

    Sánchez-Martín, Francisco Javier; Lindquist, Diana M.; Landero-Figueroa, Julio; Zhang, Xiang; Chen, Jing; Cecil, Kim M.; Medvedovic, Mario; Puga, Alvaro

    2014-01-01

    Changes in DNA methylation and subsequent changes in gene expression regulation are the hallmarks of age- and tissue-dependent epigenetic drift and plasticity resulting from the combinatorial integration of genetic determinants and environmental cues. To determine whether perinatal lead exposure caused persistent DNA methylation changes in target tissues, we exposed mouse dams to 0, 3 or 30 ppm of lead acetate in drinking water for a period extending from 2 months prior to mating, through gestation, until weaning of pups at postnatal day-21, and analyzed whole-genome DNA methylation in brain cortex and hippocampus of 2-month old exposed and unexposed progeny. Lead exposure resulted in hypermethylation of three differentially methylated regions in the hippocampus of females, but not males. These regions mapped to Rn4.5s, Sfi1, and Rn45s loci in mouse chromosomes 2, 11 and 17, respectively. At a conservative fdr<0.001, 1,623 additional CpG sites were differentially methylated in female hippocampus, corresponding to 117 unique genes. Sixty of these genes were tested for mRNA expression and showed a trend towards negative correlation between mRNA expression and methylation in exposed females but not males. No statistically significant methylome changes were detected in male hippocampus or in cortex of either sex. We conclude that exposure to lead during embryonic life, a time when the organism is most sensitive to environmental cues, appears to have a sex- and tissue-specific effect on DNA methylation that may produce pathological or physiological deviations from the epigenetic plasticity operative in unexposed mice. PMID:25530354

  12. Candida albicans exposures, sex specificity and cognitive deficits in schizophrenia and bipolar disorder.

    PubMed

    Severance, Emily G; Gressitt, Kristin L; Stallings, Catherine R; Katsafanas, Emily; Schweinfurth, Lucy A; Savage, Christina L; Adamos, Maria B; Sweeney, Kevin M; Origoni, Andrea E; Khushalani, Sunil; Leweke, F Markus; Dickerson, Faith B; Yolken, Robert H

    2016-01-01

    Immune aberrations in schizophrenia and bipolar disorder have led to the hypotheses that infectious agents or corresponding immune responses might contribute to psychiatric etiopathogeneses. We investigated case-control differences in exposure to the opportunistic fungal pathogen, Candida albicans, and examined associations with cognition, medication, lifestyle, and somatic conditions. We quantified C. albicans IgG antibodies in two cohorts totaling 947 individuals and evaluated odds ratios (OR) of exposure with psychiatric disorder using multivariate regressions. The case-control cohort included 261 with schizophrenia, 270 with bipolar disorder, and 277 non-psychiatric controls; the second included 139 with first-episode schizophrenia, 78 of whom were antipsychotic naive. No differences in C. albicans exposures were found until diagnostic groups were stratified by sex. In males, C. albicans seropositivity conferred increased odds for a schizophrenia diagnosis (OR 2.04-9.53, P⩽0.0001). In females, C. albicans seropositivity conferred increased odds for lower cognitive scores on Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in schizophrenia (OR 1.12, P⩽0.004), with significant decreases on memory modules for both disorders (P⩽0.0007-0.03). C. albicans IgG levels were not impacted by antipsychotic medications. Gastrointestinal (GI) disturbances were associated with elevated C. albicans in males with schizophrenia and females with bipolar disorder (P⩽0.009-0.02). C. albicans exposure was associated with homelessness in bipolar males (P⩽0.0015). In conclusion, sex-specific C. albicans immune responses were evident in psychiatric disorder subsets. Inquiry regarding C. albicans infection or symptoms may expedite amelioration of this treatable comorbid condition. Yeast exposure as a risk factor for schizophrenia and its associated cognitive and GI effects require further investigation including the possible contribution of gut

  13. Candida albicans exposures, sex specificity and cognitive deficits in schizophrenia and bipolar disorder

    PubMed Central

    Severance, Emily G; Gressitt, Kristin L; Stallings, Catherine R; Katsafanas, Emily; Schweinfurth, Lucy A; Savage, Christina L; Adamos, Maria B; Sweeney, Kevin M; Origoni, Andrea E; Khushalani, Sunil; Leweke, F Markus; Dickerson, Faith B; Yolken, Robert H

    2016-01-01

    Immune aberrations in schizophrenia and bipolar disorder have led to the hypotheses that infectious agents or corresponding immune responses might contribute to psychiatric etiopathogeneses. We investigated case–control differences in exposure to the opportunistic fungal pathogen, Candida albicans, and examined associations with cognition, medication, lifestyle, and somatic conditions. We quantified C. albicans IgG antibodies in two cohorts totaling 947 individuals and evaluated odds ratios (OR) of exposure with psychiatric disorder using multivariate regressions. The case–control cohort included 261 with schizophrenia, 270 with bipolar disorder, and 277 non-psychiatric controls; the second included 139 with first-episode schizophrenia, 78 of whom were antipsychotic naive. No differences in C. albicans exposures were found until diagnostic groups were stratified by sex. In males, C. albicans seropositivity conferred increased odds for a schizophrenia diagnosis (OR 2.04–9.53, P⩽0.0001). In females, C. albicans seropositivity conferred increased odds for lower cognitive scores on Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in schizophrenia (OR 1.12, P⩽0.004), with significant decreases on memory modules for both disorders (P⩽0.0007–0.03). C. albicans IgG levels were not impacted by antipsychotic medications. Gastrointestinal (GI) disturbances were associated with elevated C. albicans in males with schizophrenia and females with bipolar disorder (P⩽0.009–0.02). C. albicans exposure was associated with homelessness in bipolar males (P⩽0.0015). In conclusion, sex-specific C. albicans immune responses were evident in psychiatric disorder subsets. Inquiry regarding C. albicans infection or symptoms may expedite amelioration of this treatable comorbid condition. Yeast exposure as a risk factor for schizophrenia and its associated cognitive and GI effects require further investigation including the possible contribution of

  14. Sex-specific foraging behavior in response to fishing activities in a threatened seabird

    PubMed Central

    García-Tarrasón, Manuel; Bécares, Juan; Bateman, Santiago; Arcos, José Manuel; Jover, Lluís; Sanpera, Carolina

    2015-01-01

    Some seabird species have learnt to efficiently exploit fishing discards from trawling activities. However, a discard ban has been proposed as necessary in Europe to ensure the sustainability of the seas. It is of crucial importance for the management and conservation purposes to study the potential consequences of a discard ban on the foraging ecology of threatened seabirds. We assessed the influence of fishing activities on the feeding habits of 22 male and 15 female Audouin's gulls (Larus audouinii) from the Ebro Delta (Mediterranean Sea) during the breeding period using GPS loggers together with Stable Isotope Analysis (SIA), which provided new insights into their foraging behavior and trophic ecology, respectively. GPS data revealed different sex-specific foraging patterns between workdays and weekends. Females were highly consistent in that they foraged at sea throughout the week even though discarding stops at weekends. In contrast, males switched from foraging at sea during the week (when discards are produced) to an increased use of rice field habitats at weekends (when fishermen do not work). This sex-specific foraging behavior could be related to specific nutritional requirements associated with previous egg production, an energetically demanding period for females. However, on a broader time scale integrated by the SIA, both sexes showed a high degree of individual specialization in their trophic ecology. The need to obtain detailed information on the dependence and response of seabirds to fishing activities is crucial in conservation sciences. In this regard, sex-specific foraging behavior in relation to fisheries has been overlooked, despite the ecological and conservation implications. For instance, this situation may lead to sex differentiation in bycatch mortality in longlines when trawlers do not operate. Moreover, any new fisheries policy will need to be implemented gradually to facilitate the adaptation of a specialized species to a discard ban

  15. Sex-specific foraging behavior in response to fishing activities in a threatened seabird.

    PubMed

    García-Tarrasón, Manuel; Bécares, Juan; Bateman, Santiago; Arcos, José Manuel; Jover, Lluís; Sanpera, Carolina

    2015-06-01

    Some seabird species have learnt to efficiently exploit fishing discards from trawling activities. However, a discard ban has been proposed as necessary in Europe to ensure the sustainability of the seas. It is of crucial importance for the management and conservation purposes to study the potential consequences of a discard ban on the foraging ecology of threatened seabirds. We assessed the influence of fishing activities on the feeding habits of 22 male and 15 female Audouin's gulls (Larus audouinii) from the Ebro Delta (Mediterranean Sea) during the breeding period using GPS loggers together with Stable Isotope Analysis (SIA), which provided new insights into their foraging behavior and trophic ecology, respectively. GPS data revealed different sex-specific foraging patterns between workdays and weekends. Females were highly consistent in that they foraged at sea throughout the week even though discarding stops at weekends. In contrast, males switched from foraging at sea during the week (when discards are produced) to an increased use of rice field habitats at weekends (when fishermen do not work). This sex-specific foraging behavior could be related to specific nutritional requirements associated with previous egg production, an energetically demanding period for females. However, on a broader time scale integrated by the SIA, both sexes showed a high degree of individual specialization in their trophic ecology. The need to obtain detailed information on the dependence and response of seabirds to fishing activities is crucial in conservation sciences. In this regard, sex-specific foraging behavior in relation to fisheries has been overlooked, despite the ecological and conservation implications. For instance, this situation may lead to sex differentiation in bycatch mortality in longlines when trawlers do not operate. Moreover, any new fisheries policy will need to be implemented gradually to facilitate the adaptation of a specialized species to a discard ban

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

    PubMed

    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

  17. 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

  18. Comment on "The effect of same-sex marriage laws on different-sex marriage: evidence from the Netherlands".

    PubMed

    Dinno, Alexis

    2014-12-01

    In the recent Demography article titled "The Effect of Same-Sex Marriage Laws on Different-Sex Marriage: Evidence From the Netherlands," Trandafir attempted to answer the question, Are rates of opposite sex marriage affected by legal recognition of same-sex marriages? The results of his approach to statistical inference-looking for evidence of a difference in rates of opposite-sex marriage-provide an absence of evidence of such effects. However, the validity of his conclusion of no causal relationship between same-sex marriage laws and rates of opposite-sex marriage is threatened by the fact that Trandafir did not also look for equivalence in rates of opposite-sex marriage in order to provide evidence of an absence of such an effect. Equivalence tests in combination with difference tests are introduced and presented in this article as a more valid inferential approach to the substantive question Trandafir attempted to answer. PMID:25331494

  19. Prenatal Bisphenol A Exposure Alters Sex-Specific Estrogen Receptor Expression in the Neonatal Rat Hypothalamus and Amygdala

    PubMed Central

    Patisaul, Heather B.

    2013-01-01

    Bisphenol A (BPA) exposure is ubiquitous, and in laboratory animals, early-life BPA exposure has been shown to alter sex-specific neural organization, neuroendocrine physiology, and behavior. The specific mechanisms underlying these brain-related outcomes, however, remain largely unknown, constraining the capacity to ascertain the potential human relevance of neural effects observed in animal models. In the perinatal rat brain, estrogen is masculinizing, suggesting that BPA-induced perturbation of estrogen receptor (ESR) expression may underpin later in-life neuroendocrine effects. We hypothesized that prenatal BPA exposure alters sex-specific ESR1 (ERα) and ESR2 (ERβ) expression in postnatal limbic nuclei. Sprague Dawley rats were mated and gavaged on gestational days (GDs) 6–21 with vehicle, 2.5 or 25 μg/kg bw/day BPA, or 5 or 10 μg/kg bw/day ethinyl estradiol. An additional group was restrained but not gavaged (naïve control). Offspring were sacrificed the day after birth to quantify ESR gene expression throughout the hypothalamus and amygdala by in situ hybridization. Relative to the vehicle group, significant effects of BPA were observed on ESR1 and ESR2 expression throughout the mediobasal hypothalamus and amygdala in both sexes. Significant differences in ESR expression were also observed in the mediobasal hypothalamus and amygdala of the naïve control group compared with the vehicle group, highlighting the potential for gavage to influence gene expression in the developing brain. These results indicate that ESR expression in the neonatal brain of both sexes can be altered by low-dose prenatal BPA exposure. PMID:23457122

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

    PubMed

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

    2013-01-01

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

  1. Effects of Sex and Gender on Adaptations to Space: Reproductive Health

    PubMed Central

    Baker, Ellen S.; Bavendam, Tamara G.; Beck, Kevin D.; Miller, Virginia M.; Tash, Joseph S.; Jenkins, Marjorie

    2014-01-01

    Abstract In this report, sex/gender research relevant to reproduction on Earth, in conjunction with the extant human and animal observations in space, was used to identify knowledge gaps and prioritize recommendations for future sex- and gender-specific surveillance and monitoring of male and female astronauts. With overall increased durations of contemporary space missions, a deeper understanding of sex/gender effects on reproduction-related responses and adaptations to the space environment is warranted to minimize risks and insure healthy aging of the men and women who travel into space. PMID:25401943

  2. Effects of sex and gender on adaptations to space: reproductive health.

    PubMed

    Ronca, April E; Baker, Ellen S; Bavendam, Tamara G; Beck, Kevin D; Miller, Virginia M; Tash, Joseph S; Jenkins, Marjorie

    2014-11-01

    In this report, sex/gender research relevant to reproduction on Earth, in conjunction with the extant human and animal observations in space, was used to identify knowledge gaps and prioritize recommendations for future sex- and gender-specific surveillance and monitoring of male and female astronauts. With overall increased durations of contemporary space missions, a deeper understanding of sex/gender effects on reproduction-related responses and adaptations to the space environment is warranted to minimize risks and insure healthy aging of the men and women who travel into space. PMID:25401943

  3. Antenatal glucocorticoid exposure enhances the inhibition of adrenal steroidogenesis by leptin in a sex-specific fashion.

    PubMed

    Su, Yixin; Carey, Luke C; Rose, James C; Pulgar, Victor M

    2013-06-15

    Antenatal treatment with glucocorticoids (GC) poses long-lasting effects on endocrine and cardiovascular function. Given that leptin attenuates adrenal function and the reported sex differences in plasma leptin concentration, we hypothesized that antenatal GC will affect leptin levels and leptin modulation of adrenal function in a sex-specific manner. Pregnant sheep were randomly given betamethasone or vehicle at 80 days of gestational age, and offspring were allowed to deliver at term. Adrenocortical cells (ADC) were studied from male and female animals at 1.5 yr of age. Plasma leptin was increased 66% in male and 41% in female GC-treated animals (P < 0.05), but adrenal leptin mRNA was increased only in GC-treated males (P < 0.05). Whereas mRNA expression of adrenal leptin receptor isoforms showed sex (Ob-Ra and Ob-Rb) and treatment-dependent (Ob-Rb) differences, protein expression remained unchanged. GC-treated females showed greater plasma cortisol and greater ACTH-stimulated cortisol production (P < 0.05) in ADC. Leptin exerted a greater inhibitory effect on basal and stimulated cortisol by ADC from GC-treated males (P < 0.05), with no differences in females. Similarly, greater inhibitory effects on basal and ACTH-stimulated StAR and ACTH-R mRNA expression by leptin were observed in cells from GC males (P < 0.05), with no changes in females. Persistent effects of antenatal GC on leptin levels and leptin modulation of adrenal function are expressed in a sex-specific manner; males are more sensitive than females to the inhibitory influences of leptin on adrenal function, and this effect appears to be mediated by a greater inhibition of StAR and ACTH-R expression in adrenals of adult GC-treated males. PMID:23632631

  4. Antenatal glucocorticoid exposure enhances the inhibition of adrenal steroidogenesis by leptin in a sex-specific fashion

    PubMed Central

    Su, Yixin; Carey, Luke C.; Rose, James C.

    2013-01-01

    Antenatal treatment with glucocorticoids (GC) poses long-lasting effects on endocrine and cardiovascular function. Given that leptin attenuates adrenal function and the reported sex differences in plasma leptin concentration, we hypothesized that antenatal GC will affect leptin levels and leptin modulation of adrenal function in a sex-specific manner. Pregnant sheep were randomly given betamethasone or vehicle at 80 days of gestational age, and offspring were allowed to deliver at term. Adrenocortical cells (ADC) were studied from male and female animals at 1.5 yr of age. Plasma leptin was increased 66% in male and 41% in female GC-treated animals (P < 0.05), but adrenal leptin mRNA was increased only in GC-treated males (P < 0.05). Whereas mRNA expression of adrenal leptin receptor isoforms showed sex (Ob-Ra and Ob-Rb) and treatment-dependent (Ob-Rb) differences, protein expression remained unchanged. GC-treated females showed greater plasma cortisol and greater ACTH-stimulated cortisol production (P < 0.05) in ADC. Leptin exerted a greater inhibitory effect on basal and stimulated cortisol by ADC from GC-treated males (P < 0.05), with no differences in females. Similarly, greater inhibitory effects on basal and ACTH-stimulated StAR and ACTH-R mRNA expression by leptin were observed in cells from GC males (P < 0.05), with no changes in females. Persistent effects of antenatal GC on leptin levels and leptin modulation of adrenal function are expressed in a sex-specific manner; males are more sensitive than females to the inhibitory influences of leptin on adrenal function, and this effect appears to be mediated by a greater inhibition of StAR and ACTH-R expression in adrenals of adult GC-treated males. PMID:23632631

  5. Age-specific and sex-specific morbidity and mortality from avian influenza A(H7N9).

    PubMed

    Dudley, Joseph P; Mackay, Ian M

    2013-11-01

    We used data on age and sex for 136 laboratory confirmed human A(H7N9) cases reported as of 11 August 2013 to compare age-specific and sex-specific patterns of morbidity and mortality from the avian influenza A(H7N9) virus with those of the avian influenza A(H5N1) virus. Human A(H7N9) cases exhibit high degrees of age and sex bias: mortality is heavily biased toward males >50 years, no deaths have been reported among individuals <25 years old, and relatively few cases documented among children or adolescents. The proportion of fatal cases (PFC) for human A(H7N9) cases as of 11 August 2013 was 32%, compared to a cumulative PFC for A(H5N1) of 83% in Indonesia and 36% in Egypt. Approximately 75% of cases of all A(H7N9) cases occurred among individuals >45 years old. Morbidity and mortality from A(H7N9) are lowest among individuals between 10 and 29 years, the age group which exhibits the highest cumulative morbidity and case fatality rates from A(H5N1). Although individuals <20 years old comprise nearly 50% of all human A(H5N1) cases, only 7% of all reported A(H7N9) cases and no deaths have been reported among individuals in this age group. Only 4% of A(H7N9) cases occurred among children<5 years old, and only one case from the 10 to 20 year age group. Age- and sex-related differences in morbidity and mortality from emerging zoonotic diseases can provide insights into ecological, economic, and cultural factors that may contribute to the emergence and proliferation of novel zoonotic diseases in human populations. PMID:24091087

  6. 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.

  7. A garter snake transcriptome: pyrosequencing, de novo assembly, and sex-specific differences

    PubMed Central

    2010-01-01

    Background The reptiles, characterized by both diversity and unique evolutionary adaptations, provide a comprehensive system for comparative studies of metabolism, physiology, and development. However, molecular resources for ectothermic reptiles are severely limited, hampering our ability to study the genetic basis for many evolutionarily important traits such as metabolic plasticity, extreme longevity, limblessness, venom, and freeze tolerance. Here we use massively parallel sequencing (454 GS-FLX Titanium) to generate a transcriptome of the western terrestrial garter snake (Thamnophis elegans) with two goals in mind. First, we develop a molecular resource for an ectothermic reptile; and second, we use these sex-specific transcriptomes to identify differences in the presence of expressed transcripts and potential genes of evolutionary interest. Results Using sex-specific pools of RNA (one pool for females, one pool for males) representing 7 tissue types and 35 diverse individuals, we produced 1.24 million sequence reads, which averaged 366 bp in length after cleaning. Assembly of the cleaned reads from both sexes with NEWBLER and MIRA resulted in 96,379 contigs containing 87% of the cleaned reads. Over 34% of these contigs and 13% of the singletons were annotated based on homology to previously identified proteins. From these homology assignments, additional clustering, and ORF predictions, we estimate that this transcriptome contains ~13,000 unique genes that were previously identified in other species and over 66,000 transcripts from unidentified protein-coding genes. Furthermore, we use a graph-clustering method to identify contigs linked by NEWBLER-split reads that represent divergent alleles, gene duplications, and alternatively spliced transcripts. Beyond gene identification, we identified 95,295 SNPs and 31,651 INDELs. From these sex-specific transcriptomes, we identified 190 genes that were only present in the mRNA sequenced from one of the sexes (84

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

    PubMed Central

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

    2014-01-01

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

  9. The cyclic AMP pathway is a sex-specific modifier of glioma risk in type I neurofibromatosis patients.

    PubMed

    Warrington, Nicole M; Sun, Tao; Luo, Jingqin; McKinstry, Robert C; Parkin, Patricia C; Ganzhorn, Sara; Spoljaric, Debra; Albers, Anne C; Merkelson, Amanda; Stewart, Douglas R; Stevenson, David A; Viskochil, David; Druley, Todd E; Forys, Jason T; Reilly, Karlyne M; Fisher, Michael J; Tabori, Uri; Allen, Jeffrey C; Schiffman, Joshua D; Gutmann, David H; Rubin, Joshua B

    2015-01-01

    Identifying modifiers of glioma risk in patients with type I neurofibromatosis (NF1) could help support personalized tumor surveillance, advance understanding of gliomagenesis, and potentially identify novel therapeutic targets. Here, we report genetic polymorphisms in the human adenylate cyclase gene adenylate cyclase 8 (ADCY8) that correlate with glioma risk in NF1 in a sex-specific manner, elevating risk in females while reducing risk in males. This finding extends earlier evidence of a role for cAMP in gliomagenesis based on results in a genetically engineered mouse model (Nf1 GEM). Thus, sexually dimorphic cAMP signaling might render males and females differentially sensitive to variation in cAMP levels. Using male and female Nf1 GEM, we found significant sex differences exist in cAMP regulation and in the growth-promoting effects of cAMP suppression. Overall, our results establish a sex-specific role for cAMP regulation in human gliomagenesis, specifically identifying ADCY8 as a modifier of glioma risk in NF1. PMID:25381154

  10. Mortality trajectory analysis reveals the drivers of sex-specific epidemiology in natural wildlife–disease interactions

    PubMed Central

    McDonald, Jennifer L.; Smith, Graham C.; McDonald, Robbie A.; Delahay, Richard J.; Hodgson, Dave

    2014-01-01

    In animal populations, males are commonly more susceptible to disease-induced mortality than females. However, three competing mechanisms can cause this sex bias: weak males may simultaneously be more prone to exposure to infection and mortality; being ‘male’ may be an imperfect proxy for the underlying driver of disease-induced mortality; or males may experience increased severity of disease-induced effects compared with females. Here, we infer the drivers of sex-specific epidemiology by decomposing fixed mortality rates into mortality trajectories and comparing their parameters. We applied Bayesian survival trajectory analysis to a 22-year longitudinal study of a population of badgers (Meles meles) naturally infected with bovine tuberculosis (bTB). At the point of infection, infected male and female badgers had equal mortality risk, refuting the hypothesis that acquisition of infection occurs in males with coincidentally high mortality. Males and females exhibited similar levels of heterogeneity in mortality risk, refuting the hypothesis that maleness is only a proxy for disease susceptibility. Instead, sex differences were caused by a more rapid increase in male mortality rates following infection. Males are indeed more susceptible to bTB, probably due to immunological differences between the sexes. We recommend this mortality trajectory approach for the study of infection in animal populations. PMID:25056621