Sample records for sterile male sexual

  1. Sexual competitiveness of Vienna 4\\/Tol-94 ‘genetic sexing’ sterile mediterranean fruit fly males in Israel

    Microsoft Academic Search

    Phillip W. Taylor; Allon Bear; Yoav Gazit; Yoram Rössler

    2001-01-01

    The sterile insect technique (SIT) is used as an environment-friendly means of suppressing Mediterranean fruit fly (Ceratitis capitata; ‘medfly’) populations in the Arava valley of Israel. The technique depends on released sterile males effectively wresting\\u000a the reproductive potential away from wild, fertile males. Studies carried out in other countries have indicated that sterile\\u000a males may sometimes be of inferior sexual

  2. Cytoplasmic male-sterility

    Microsoft Academic Search

    John R. Edwardson

    1956-01-01

    Cytoplasmic inheritance is of theoretical importance--it may be of even greater practical importance, for, when it involves malesterilitylas in many instances it does--it may make hybridization easier. It may also make possible the use of heterosis in plants otherwise difficult to hybridize. The effect of the cytoplasm on the inheritance of male-sterility was speculated on before the rediscovery of Mendel's

  3. Engineered Male Sterility

    Microsoft Academic Search

    Frank Kempken

    \\u000a \\u000a The agricultural exploitation of hybrid crop varieties has enabled enormous increases in food productivity through increased\\u000a uniformity and hybrid vigour. Because of hybrid vigour, or heterosis\\u000a , these crops are characterized by an increased resistance to disease and enhanced performance in different environments when\\u000a comparing the heterozygous hybrid progeny (called F1 hybrids) to the homozygous parents. The generation of male

  4. Methoprene treatment reduces the pre-copulatory period in Anastrepha fraterculus (Diptera: Tephritidae) sterile males

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anastrepha fraterculus is a major fruit pest in South America. Ongoing studies encourage the implementation of the sterile insect technique (SIT) against this pest. Sexual readiness of sterile males is a key point for SIT. The time required for A. fraterculus males to become sexually mature is unkn...

  5. The sterile male technique: irradiation negatively affects male fertility but not male courtship.

    PubMed

    Magris, Martina; Wignall, Anne E; Herberstein, Marie E

    2015-04-01

    The sterile male technique is a common method to assign paternity, widely adopted due to its relative simplicity and low cost. Male sterility is induced by exposure to sub lethal doses of chemosterilants or irradiation, the dosage of which has to be calibrated for every species to provide successful male sterilisation, without affecting male physiology and behaviour. While the physiological effects of sterilisation are usually assessed for each study, the behavioural ones are rarely analysed in detail. Using the orb web spider Argiope keyserlingi as a model we first tested (1) the validity of the thread assay, which simulates male courtship behaviour in a standardised context, as a proxy representing courtship on a female web. We then investigated (2) the effectiveness of male sterilisation via irradiation and (3) its consequences on male courtship behaviour. Our results validate the thread assay and the sterile male technique as legitimate tools for the study of male courtship behaviour and fertilisation success. We show that these techniques are time and cost effective and reduce undesirable variation, thereby creating opportunities to study and understand the mechanisms underlying sexual selection. PMID:25794431

  6. Male sterility and fertility restoration in crops.

    PubMed

    Chen, Letian; Liu, Yao-Guang

    2014-01-01

    In plants, male sterility can be caused either by mitochondrial genes with coupled nuclear genes or by nuclear genes alone; the resulting conditions are known as cytoplasmic male sterility (CMS) and genic male sterility (GMS), respectively. CMS and GMS facilitate hybrid seed production for many crops and thus allow breeders to harness yield gains associated with hybrid vigor (heterosis). In CMS, layers of interaction between mitochondrial and nuclear genes control its male specificity, occurrence, and restoration of fertility. Environment-sensitive GMS (EGMS) mutants may involve epigenetic control by noncoding RNAs and can revert to fertility under different growth conditions, making them useful breeding materials in the hybrid seed industry. Here, we review recent research on CMS and EGMS systems in crops, summarize general models of male sterility and fertility restoration, and discuss the evolutionary significance of these reproductive systems. PMID:24313845

  7. The Sterile Insect Technique for Controlling Populations of Aedes albopictus (Diptera: Culicidae) on Reunion Island: Mating Vigour of Sterilized Males

    PubMed Central

    Oliva, Clelia F.; Jacquet, Maxime; Gilles, Jeremie; Lemperiere, Guy; Maquart, Pierre-Olivier; Quilici, Serge; Schooneman, François; Vreysen, Marc J. B.; Boyer, Sebastien

    2012-01-01

    Reunion Island suffers from high densities of the chikungunya and dengue vector Aedes albopictus. The sterile insect technique (SIT) offers a promising strategy for mosquito-borne diseases prevention and control. For such a strategy to be effective, sterile males need to be competitive enough to fulfil their intended function by reducing wild mosquito populations in natura. We studied the effect of irradiation on sexual maturation and mating success of males, and compared the sexual competitiveness of sterile versus wild males in the presence of wild females in semi-field conditions. For all untreated or sterile males, sexual maturation was completed within 13 to 20 h post-emergence and some males were able to inseminate females when 15 h old. In the absence of competition, untreated and sterile males were able to inseminate the same number of virgin females during 48 h, in small laboratory cages: an average of 93% of females was inseminated no matter the treatment, the age of males, and the sex ratio. Daily mating success of single sterile males followed the same pattern as for untreated ones, although they inseminated significantly fewer females after the ninth day. The competitiveness index of sterile males in semi-field conditions was only 0.14 when they were released at 1-day old, but improved to 0.53 when the release occurred after a 5-day period in laboratory conditions. In SIT simulation experiments, a 5?1 sterile to wild male ratio allowed a two-fold reduction of the wild population’s fertility. This suggests that sterile males could be sufficiently competitive to mate with wild females within the framework of an SIT component as part of an AW-IPM programme for suppressing a wild population of Ae. albopictus in Reunion Island. It will be of interest to minimise the pre-release period in controlled conditions to ensure a good competitiveness without increasing mass rearing costs. PMID:23185329

  8. Transfer of Ogu cytoplasmic male sterility to Brassica juncea and improvement of the male sterile line through somatic cell fusion

    Microsoft Academic Search

    P. B. Kirti; S. S. Banga; S. Prakash; V. L. Chopra

    1995-01-01

    Male sterility conferred by ogu cytoplasm of Raphanus sativus has been transferred to Brassica juncea cv ‘RLM 198’ from male-sterile B. napus through repeated backcrossing and selection. The male-sterile B. juncea is, however, highly chlorotic and late. It has low female (seed) fertility and small contorted pods. To rectify these defects, protoplasts of the male sterile were fused with normal

  9. Sperm precedence in Callosobruchus chinensis estimated using the sterile male technique

    Microsoft Academic Search

    Tomohiro Harano; Yutaka Nakamoto; Takahisa Miyatake

    2008-01-01

    P2, the proportion of offspring sired by the second male to mate, is an indicator of the outcome of postcopulatory sexual selection,\\u000a which occurs through sperm competition and\\/or cryptic female choice. We determined the appropriate dose of gamma radiation\\u000a for sterilization of adult males and, using the sterile male technique, measured P2 in the adzuki bean beetle, Callosobruchus chinensis. Adult

  10. Effects of male sterility on female remating in the mediterranean fruitfly, Ceratitis capitata.

    PubMed Central

    Kraaijeveld, Ken; Chapman, Tracey

    2004-01-01

    Mating-induced reductions in female receptivity are common in insects. These responses are of interest because of their utility in insect pest control. In addition, the control of receptivity is likely to be the subject of sexual conflict over remating frequency. We investigated the specific effect of male sterility on female receptivity in an important pest species, the Mediterranean fruitfly (medfly), in which sterile males are often used for population suppression. Sterile males performed less courtship, obtained significantly fewer first and second matings than fertile males, and reduced female receptivity significantly less effectively than did fertile males. We modelled the likelihood of fertile matings and show that the low mating success of sterile males represents a significant problem for medfly sterile insect technique (SIT) programmes. PMID:15252986

  11. Cytoplasmic male sterility in the olive (Olea europaea L.)

    Microsoft Academic Search

    G. Besnard; B. Khadari; P. Villemur; A. Bervillé

    2000-01-01

    The olive tree is usually hermaphrodite but self-incompatible. In the Western Mediterranean some cultivars are totally male-sterile.\\u000a Three different male-sterile phenotypes have been recognised. To infer the genetic basis of male sterility we studied its\\u000a inheritance and cytoplasmic diversity in wild (oleaster) and cultivated Mediterranean olive. In the cross Olivière×Arbequina, the male-sterile trait was maternally inherited and affected all progenies.

  12. Mitochondrial gene expression and cytoplasmic male sterility in sorghum

    Microsoft Academic Search

    Linda K. Dixon; Christopher J. Leaver

    1982-01-01

    Variation in sorghum mitochondrial translation products has enabled fertile (Kafir) cytoplasm to be distinguished from Milo cytoplasmic male sterile cytoplasm and from three alternative sources of cytoplasmic male sterile cytoplasm. Mitochondria from Milo cytoplasm synthesised a 65 000 mol. wt. polypeptide which was not synthesised by those from Kafir cytoplasm. In the cytoplasmic male sterile combination of Kafir nucleus in

  13. INVESTIGATION Genetic Architecture of Male Sterility and Segregation

    E-print Network

    Dean, Matthew D.

    INVESTIGATION Genetic Architecture of Male Sterility and Segregation Distortion in Drosophila of the genetic architecture underlying hybrid male sterility and segregation distortion between the Bogota to be necessary but not sufficient for both male sterility and segregation distortion in F1 hybrids between

  14. A Single Gene Causes Both Male Sterility and Segregation Distortion

    E-print Network

    Sorenson, Michael

    A Single Gene Causes Both Male Sterility and Segregation Distortion in Drosophila Hybrids Nitin the evolution of postzygotic isolation. Here, we show that the same gene, Overdrive, causes both male sterility hybrid males that are nearly completely sterile, whereas all other F1 hybrids are fertile (19). Hybrid

  15. Construction of backcrossed Gelidium male-sterile and male-fertile lines and their growth comparison

    Microsoft Academic Search

    Mohsin U. Patwary; John P. van der Meer

    1996-01-01

    The male sterility gene from a male-sterile, green,Gelidium vagum line was introduced to a wild-type line through repeated backcrossing and selection for five generations. The plants from the recurrent parent, the male-sterile green, the backcross-5 fertile and the backcross-5 male-sterile lines were compared for their growth performance. The backcross-5, red, male-sterile plants grew at a significantly higher rate than the

  16. Developmental Transitions in Male Sexuality.

    ERIC Educational Resources Information Center

    Lewis, Robert; And Others

    1978-01-01

    The article defines and elaborates on eight transitions in male sexuality, the first being the gender identity transition, and the last being the male climacteric. It discusses society's lack of support. Originally presented at the American Sociological Association Session on the Male Role in Society, New York City, 1976. (LPG)

  17. Defective pollen wall contributes to male sterility in the male sterile line 1355A of cotton.

    PubMed

    Wu, Yuanlong; Min, Ling; Wu, Zancheng; Yang, Li; Zhu, Longfu; Yang, Xiyan; Yuan, Daojun; Guo, Xiaoping; Zhang, Xianlong

    2015-01-01

    To understand the mechanisms of male sterility in cotton (Gossypium spp.), combined histological, biochemical and transcription analysis using RNA-Seq was carried out in the anther of the single-gene recessive genic male sterility system of male sterile line 1355A and male fertile line 1355B, which are near-isogenic lines (NILs) differing only in the fertility trait. A total of 2,446 differentially expressed genes were identified between the anthers of 1355AB lines, at three different stages of development. Cluster analysis and functional assignment of differentially expressed genes revealed differences in transcription associated with pollen wall and anther development, including the metabolism of fatty acids, glucose, pectin and cellulose. Histological and biochemical analysis revealed that a major cellular defect in the 1355A was a thicker nexine, consistent with the RNA-seq data, and further gene expression studies implicated differences in fatty acids synthesis and metabolism. This study provides insight into the phenotypic characteristics and gene regulatory network of the genic male sterile line 1355A in upland cotton. PMID:26043720

  18. Defective pollen wall contributes to male sterility in the male sterile line 1355A of cotton

    PubMed Central

    Wu, Yuanlong; Min, Ling; Wu, Zancheng; Yang, Li; Zhu, Longfu; Yang, Xiyan; Yuan, Daojun; Guo, Xiaoping; Zhang, Xianlong

    2015-01-01

    To understand the mechanisms of male sterility in cotton (Gossypium spp.), combined histological, biochemical and transcription analysis using RNA-Seq was carried out in the anther of the single-gene recessive genic male sterility system of male sterile line 1355A and male fertile line 1355B, which are near-isogenic lines (NILs) differing only in the fertility trait. A total of 2,446 differentially expressed genes were identified between the anthers of 1355AB lines, at three different stages of development. Cluster analysis and functional assignment of differentially expressed genes revealed differences in transcription associated with pollen wall and anther development, including the metabolism of fatty acids, glucose, pectin and cellulose. Histological and biochemical analysis revealed that a major cellular defect in the 1355A was a thicker nexine, consistent with the RNA-seq data, and further gene expression studies implicated differences in fatty acids synthesis and metabolism. This study provides insight into the phenotypic characteristics and gene regulatory network of the genic male sterile line 1355A in upland cotton. PMID:26043720

  19. The cytoplasmic inheritance of male sterility in Zea mays

    Microsoft Academic Search

    Marcus M. Rhoades

    1933-01-01

    X. Summary  1. The analyses of a male-sterile condition inZea mays indicate that the egg cytoplasm plays the chief rôle in the expression of the character.\\u000a \\u000a 2. There was no transmission of the male-sterility through the pollen of partially sterile plants.\\u000a \\u000a \\u000a 3. A replacement of the chromosomes in the male-sterile line with chromosomes known to be free from sterility-producing factors\\u000a had

  20. The Nucleo-Mitochondrial Conflict in Cytoplasmic Male Sterilities Revisited

    Microsoft Academic Search

    Françoise Budar; Pascal Touzet; Rosine De Paepe

    2003-01-01

    Cytoplasmic male sterility (CMS) in plants is a classical example of genomic conflict, opposing maternally-inherited cytoplasmic genes (mitochondrial genes in most cases), which induce male sterility, and nuclear genes, which restore male fertility. In natural populations, this type of sex control leads to gynodioecy, that is, the co-occurrence of female and hermaphroditic individuals within a population. According to theoretical models,

  1. Male sexual dysfunction in Asia

    PubMed Central

    Ho, Christopher CK; Singam, Praveen; Hong, Goh Eng; Zainuddin, Zulkifli Md

    2011-01-01

    Sex has always been a taboo subject in Asian society. However, over the past few years, awareness in the field of men's sexual health has improved, and interest in sexual health research has recently increased. The epidemiology and prevalence of erectile dysfunction, hypogonadism and premature ejaculation in Asia are similar in the West. However, several issues are specific to Asian males, including culture and beliefs, awareness, compliance and the availability of traditional/complementary medicine. In Asia, sexual medicine is still in its infancy, and a concerted effort from the government, relevant societies, physicians and the media is required to propel sexual medicine to the forefront of health care. PMID:21643001

  2. Hybrid male sterility and genome-wide misexpression of male reproductive proteases.

    PubMed

    Gomes, Suzanne; Civetta, Alberto

    2015-01-01

    Hybrid male sterility is a common barrier to gene flow between species. Previous studies have posited a link between misregulation of spermatogenesis genes in interspecies hybrids and sterility. However, in the absence of fully fertile control hybrids, it is impossible to differentiate between misregulation associated with sterility vs. fast male gene regulatory evolution. Here, we differentiate between these two possibilities using a D. pseudoobscura species pair that experiences unidirectional hybrid sterility. We identify genes uniquely misexpressed in sterile hybrid male reproductive tracts via RNA-seq. The sterile male hybrids had more misregulated and more over or under expressed genes relative to parental species than the fertile male hybrids. Proteases were the only gene ontology class overrepresented among uniquely misexpressed genes, with four located within a previously identified hybrid male sterility locus. This result highlights the potential role of a previously unexplored class of genes in interspecific hybrid male sterility and speciation. PMID:26146165

  3. Hybrid male sterility and genome-wide misexpression of male reproductive proteases

    PubMed Central

    Gomes, Suzanne; Civetta, Alberto

    2015-01-01

    Hybrid male sterility is a common barrier to gene flow between species. Previous studies have posited a link between misregulation of spermatogenesis genes in interspecies hybrids and sterility. However, in the absence of fully fertile control hybrids, it is impossible to differentiate between misregulation associated with sterility vs. fast male gene regulatory evolution. Here, we differentiate between these two possibilities using a D. pseudoobscura species pair that experiences unidirectional hybrid sterility. We identify genes uniquely misexpressed in sterile hybrid male reproductive tracts via RNA-seq. The sterile male hybrids had more misregulated and more over or under expressed genes relative to parental species than the fertile male hybrids. Proteases were the only gene ontology class overrepresented among uniquely misexpressed genes, with four located within a previously identified hybrid male sterility locus. This result highlights the potential role of a previously unexplored class of genes in interspecific hybrid male sterility and speciation. PMID:26146165

  4. Mitochondria and cytoplasmic male sterility in plants.

    PubMed

    Hu, Jun; Huang, Wenchao; Huang, Qi; Qin, Xiaojian; Yu, Changchun; Wang, Lili; Li, Shaoqing; Zhu, Renshan; Zhu, Yingguo

    2014-11-01

    Mitochondria are essential organelles in cells not only because they supply over 90% of the cell's energy but also because their dysfunction is associated with disease. Owing to the importance of mitochondria, there are many questions about mitochondria that must be answered. Cytoplasmic male sterility (CMS) is a mysterious natural phenomenon, and the mechanism of the origin of CMS is unknown. Despite successful utilization of CMS and restoration of fertility (Rf) in practice, the underlying mechanisms of these processes remain elusive. This review summarizes the genes involved in CMS and Rf, with a special focus on recent studies reporting the mechanisms of the CMS and Rf pathways, and concludes with potential working models. PMID:24566371

  5. Male Sterility-Inducing Mitochondrial Genomes: How Do They Differ?

    Microsoft Academic Search

    Tomohiko Kubo; Kazuyoshi Kitazaki; Muneyuki Matsunaga; Hiroyo Kagami; Tetsuo Mikami

    2011-01-01

    Twenty-nine mitochondrial genomes from 19 angiosperm species have been completely sequenced and have been found to vary in genome size and gene content. Seven of these mitochondrial genomes are known to induce cytoplasmic male sterility (CMS), and thus can be utilized for hybrid seed production or the prevention of pollen dispersal. Genome rearrangement frequently is observed in male sterility (MS)-inducing

  6. Regulation of Male Sexual Behavior by Progesterone Receptor, Sexual

    E-print Network

    Crews, David

    of sexual behavior following castration. In a second experiment, we tested whether male mice heterozygous and experience. © 1998 Academic Press Key Words: progesterone receptor; male; sexual be- havior; castration of experienced males to exhibit sexual behaviors following castration, and variation in the sensitivity of males

  7. Sexual Selection in Males and Females

    E-print Network

    Sorenson, Michael

    Sexual Selection in Males and Females Tim Clutton-Brock Research on sexual selection shows that the evolution of secondary sexual characters in males and the distribution of sex differences are more complex involved. However, the operation of sexual selection in females has still received relatively little

  8. Sensation seeking and males' sexual strategy

    Microsoft Academic Search

    Michael C. Seto; Martin L. Lalumière; Vernon L. Quinsey

    1995-01-01

    We examined the relationship between sensation seeking and the self-reports of both sexual interests and behaviours of 162 heterosexual male students and 60 heterosexual males recruited from the community. Because parental investment theory and previous research suggest that males' interest in sexual partner variety is constrained by females' preference for committed sexual relationships, we predicted that participants would desire to

  9. Anther developmental defects in Arabidopsis thaliana male-sterile mutants

    Microsoft Academic Search

    Paul M. Sanders; Anhthu Q. Bui; Koen Weterings; Katherine N. McIntire; Yung-Chao Hsu; Pei Yun Lee; Mai Thy Truong; T. P. Beals; R. B. Goldberg

    1999-01-01

    We identified Arabidopsis thaliana sterility mutants by screening T-DNA and EMS-mutagenized lines and characterized several male-sterile mutants with defects\\u000a specific for different anther processes. Approximately 44 and 855 sterile mutants were uncovered from the T-DNA and EMS screens,\\u000a respectively. Several mutants were studied in detail with defects that included the establishment of anther morphology, microspore\\u000a production, pollen differentiation, and anther

  10. Cytoplasmic male sterility in rapeseed ( Brassica napus L.)

    Microsoft Academic Search

    L. Erickson; I. Grant; W. Beversdorf

    1986-01-01

    Restriction patterns of chloroplast (cp) and mitochondrial (mt) DNA in Brassica napus rapeseed reveal the alloplasmic nature of cytoplasmic male sterility in this crop. Both the Shiga and Bronowski systems probably exploit cytoplasmic diversity in B. napus cultivars arising from introgression of cytoplasm from the other rapeseed species, B. campestris. Nuclear genes specific to these systems do not cause sterility

  11. Modeling the Suppression of Sea Lamprey Populations by the Release of Sterile Males or Sterile Females

    Microsoft Academic Search

    Waldemar Klassen; Jean V. Adams; Michael B. Twohey

    2004-01-01

    The suppressive effects of trapping adult sea lampreys, Petromyzon marinus Linnaeus, and releasing sterile males (SMRT) or females (SFRT) into a closed system were expressed in deterministic models. Suppression was modeled as a function of the proportion of the population removed by trapping, the number of sterile animals released, the reproductive rate and sex ratio of the population, and (for

  12. Male adolescent sexual and reproductive health care.

    PubMed

    Marcell, Arik V; Wibbelsman, Charles; Seigel, Warren M

    2011-12-01

    Male adolescents' sexual and reproductive health needs often go unmet in the primary care setting. This report discusses specific issues related to male adolescents' sexual and reproductive health care in the context of primary care, including pubertal and sexual development, sexual behavior, consequences of sexual behavior, and methods of preventing sexually transmitted infections (including HIV) and pregnancy. Pediatricians are encouraged to address male adolescent sexual and reproductive health on a regular basis, including taking a sexual history, performing an appropriate examination, providing patient-centered and age-appropriate anticipatory guidance, and delivering appropriate vaccinations. Pediatricians should provide these services to male adolescent patients in a confidential and culturally appropriate manner, promote healthy sexual relationships and responsibility, and involve parents in age-appropriate discussions about sexual health with their sons. PMID:22123881

  13. The Sexual Stereotype of the Black Male.

    ERIC Educational Resources Information Center

    Davis, Gary L.; Cross, Herbert J.

    This paper presents the results of a study to examine the existence of sexual stereotyping of black males by white college students. Subjects were 180 male and 180 female white undergraduates; they were tested in sexually segregated groups. Each read one of three types of pornographic stories (hard-core, erotic realism, or sexual fantasy). The…

  14. Mitochondrially-targeted expression of a cytoplasmic male sterility-associated orf220 gene causes male sterility in Brassica juncea

    PubMed Central

    2010-01-01

    Background The novel chimeric open reading frame (orf) resulting from the rearrangement of a mitochondrial genome is generally thought to be a causal factor in the occurrence of cytoplasmic male sterility (CMS). Both positive and negative correlations have been found between CMS-associated orfs and the occurrence of CMS when CMS-associated orfs were expressed and targeted at mitochondria. Some orfs cause male sterility or semi-sterility, while some do not. Little is currently known about how mitochondrial factor regulates the expression of the nuclear genes involved in male sterility. The purpose of this study was to investigate the biological function of a candidate CMS-associated orf220 gene, newly isolated from cytoplasmic male-sterile stem mustard, and show how mitochondrial retrograde regulated nuclear gene expression is related to male sterility. Results It was shown that the ORF220 protein can be guided to the mitochondria using the mitochondrial-targeting sequence of the ? subunit of F1-ATPase (atp2-1). Transgenic stem mustard plants expressed the chimeric gene containing the orf220 gene and a mitochondrial-targeting sequence of the ? subunit of F1-ATPase (atp2-1). Transgenic plants were male-sterile, most being unable to produce pollen while some could only produce non-vigorous pollen. The transgenic stem mustard plants also showed aberrant floral development identical to that observed in the CMS stem mustard phenotype. Results obtained from oligooarray analysis showed that some genes related to mitochondrial energy metabolism were down-regulated, indicating a weakening of mitochondrial function in transgenic stem mustard. Some genes related to pollen development were shown to be down-regulated in transgenic stem mustard and the expression of some transcription factor genes was also altered. Conclusion The work presented furthers our understanding of how the mitochondrially-targeted expression of CMS-associated orf220 gene causes male sterility through retrograde regulation of nuclear gene expression in Brassica juncea. PMID:20974011

  15. Segregation of male-sterility alleles across a species boundary.

    PubMed

    Weller, S G; Sakai, A K; Culley, T M; Duong, L; Danielson, R E

    2014-02-01

    Hybrid zones may serve as bridges permitting gene flow between species, including alleles influencing the evolution of breeding systems. Using greenhouse crosses, we assessed the likelihood that a hybrid zone could serve as a conduit for transfer of nuclear male-sterility alleles between a gynodioecious species and a hermaphroditic species with very rare females in some populations. Segregation patterns in progeny of crosses between rare females of hermaphroditic Schiedea menziesii and hermaphroditic plants of gynodioecious Schiedea salicaria heterozygous at the male-sterility locus, and between female S. salicaria and hermaphroditic plants from the hybrid zone, were used to determine whether male-sterility was controlled at the same locus in the parental species and the hybrid zone. Segregations of females and hermaphrodites in approximately equal ratios from many of the crosses indicate that the same nuclear male-sterility allele occurs in the parent species and the hybrid zone. These rare male-sterility alleles in S. menziesii may result from gene flow from S. salicaria through the hybrid zone, presumably facilitated by wind pollination in S. salicaria. Alternatively, rare male-sterility alleles might result from a reversal from gynodioecy to hermaphroditism in S. menziesii, or possibly de novo evolution of male sterility. Phylogenetic analysis indicates that some species of Schiedea have probably evolved separate sexes independently, but not in the lineage containing S. salicaria and S. menziesii. High levels of selfing and expression of strong inbreeding depression in S. menziesii, which together should favour females in populations, argue against a reversal from gynodioecy to hermaphroditism in S. menziesii. PMID:24417506

  16. Cytoplasmic male sterility-regulated novel microRNAs from maize

    Microsoft Academic Search

    Yaou Shen; Zhiming Zhang; Haijian Lin; Hailan Liu; Jie Chen; Hua Peng; Moju Cao; Tingzhao Rong; Guangtang Pan

    2011-01-01

    In higher plants, microRNA (miRNA) is involved in regulation of developmental processes, including sexual organ development.\\u000a Seven novel miRNA families with one known miRNA were isolated by constructing a small RNA library from a mixture of anther\\u000a from a cytoplasmic male sterile line and its maintainer. Two miRNAs are conserved in plant species. A total of 18 potential\\u000a targets were

  17. Sexual inadequacy in the male

    PubMed Central

    Bancroft, John

    1971-01-01

    The adequacy of sexual functioning in the male depends on a complex interaction between psychological, hormonal and neurophysiological factors. Disturbance of any one of these factors may lead to sexual inadequacy. In the majority of cases no gross abnormality is found but the absence of gross hormonal or neurophysiological abnormality does not necessarily imply a purely psychological cause. Individual variations in the pattern of response of the autonomic nervous system or in the ability to learn control of autonomic responses such as erection or ejaculation may be sufficient to account for some cases of inadequacy and in others may increase the susceptibility to psychological factors. Further research is required to clarify these undoubtedly important psychophysiological relationships. Treatment has been most successful when it has taken into account both psychological and physiological factors. The advances made by Masters & Johnson (1970) in this area have partly depended on their earlier physiological and anatomical studies of sexual response (Masters & Johnson, 1966). It may be that in some cases the use of anxiety-reducing drugs or androgens will be all that is required but further work is required to identify such cases. The placebo effects of such preparations should not be overlooked particularly as many cases of sexual inadequacy are based on lack of confidence or ignorance and require little more than good advice or reassurance. Considerable advances in our understanding of these problems have been made in the past 20 years and techniques of endocrine, physiological and behavioural assessment are now available which should enable further progress to be made in the near future.

  18. Male Sexuality and Couple Sexual Health: A Case Illustration

    Microsoft Academic Search

    Michael E. Metz; Barry W. McCarthy

    2010-01-01

    Male sexual problems are common and offer exceptional opportunities for clinicians to not only relieve distress but enhance individual and relationship satisfaction. However, limited clinical focus on sex behaviors alone often overlook this opportunity. With more comprehensive approaches, clinicians are able to both facilitate improved sexual function and to promote positive, realistic principles for healthy and satisfying male and couple

  19. Variability Among Males in Sexually Selected Attributes

    Microsoft Academic Search

    John Archer; Mani Mehdikhani

    2003-01-01

    Greater male than female variability is found in behavioral and morphological traits in animals. A theory that greater male variability is associated with variability in parental investment is described and contrasted with sexual strategies theory, which posits no sex differences in variability. Predictions from the theories were tested through meta-analyses of variance ratios for data sets involving sexually selected characteristics

  20. The role of meiotic drive in hybrid male sterility

    PubMed Central

    McDermott, Shannon R.; Noor, Mohamed A. F.

    2010-01-01

    Meiotic drive causes the distortion of allelic segregation away from Mendelian expected ratios, often also reducing fecundity and favouring the evolution of drive suppressors. If different species evolve distinct drive-suppressor systems, then hybrid progeny may be sterile as a result of negative interactions of these systems' components. Although the hypothesis that meiotic drive may contribute to hybrid sterility, and thus species formation, fell out of favour early in the 1990s, recent results showing an association between drive and sterility have resurrected this previously controversial idea. Here, we review the different forms of meiotic drive and their possible roles in speciation. We discuss the recent empirical evidence for a link between drive and hybrid male sterility, also suggesting a possible mechanistic explanation for this link in the context of chromatin remodelling. Finally, we revisit the population genetics of drive that allow it to contribute to speciation. PMID:20308102

  1. Cytoplasmic male sterility in alloplasmic Brassica juncea carrying Diplotaxis catholica cytoplasm: molecular characterization and genetics of fertility restoration

    Microsoft Academic Search

    A. Pathania; S. R. Bhat; V. Dinesh Kumar; Ashutosh; P. B. Kirti; S. Prakash; V. L. Chopra

    2003-01-01

    The present study was aimed at characterizing cytoplasmic male sterility (CMS) and identifying the fertility restorer gene for CMS ( Diplotaxis catholica) Brassica juncea derived through sexual hybridization. The fertility restorer gene was identified by crossing the CMS line with progeny plants derived from somatic hybrids of B. juncea and D. cathoilca. The CMS line is comparable to the nuclear

  2. Chromosomal monogenic dominant male sterility in chinese cabbage ( Brassica rapa supbs. pekinensis (Lour.) hanelt)

    Microsoft Academic Search

    Q. P. Meer

    1987-01-01

    Strong indication was found for the existence of a chromosal monogenic dominant male sterility-gene in chenese cabbage. This source of male sterility can be of practical use for the production of hybrid varieties. A pronounced drawback is the required removal, in the breeding and seed production stage, of the approximately 50% male fertile plants from each offspring of male sterile

  3. Genetics of Male and Female Sterility in Hybrids of Drosophila pseudoobscura and D. persimilis

    Microsoft Academic Search

    H. Allen Orr

    The genetic basis of male and female sterility in hybrids of Drosophila pseudoobscura-Drosophila persimilis was studied using backcross analysis. Previous studies indirectly assessed male fertility by measuring testis size; these studies concluded that male sterility results from an X chromosome- autosome imbalance. By directly scoring for the production of motile sperm, male sterility is shown to be largely due to

  4. Evaluation of sterility and fertility of male sterile lines in the USPB farm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybrid rice has proven to have a yield advantage of 15–20% over the best inbred cultivars at the commercial scale worldwide. At present, two methods have been successfully commercialized; the three-line and two-line systems. The three-line system consists of the male sterile (MS), maintainer and res...

  5. Genetics and Evolution of Hybrid Male Sterility in House Mice

    PubMed Central

    White, Michael A.; Stubbings, Maria; Dumont, Beth L.; Payseur, Bret A.

    2012-01-01

    Comparative genetic mapping provides insights into the evolution of the reproductive barriers that separate closely related species. This approach has been used to document the accumulation of reproductive incompatibilities over time, but has only been applied to a few taxa. House mice offer a powerful system to reconstruct the evolution of reproductive isolation between multiple subspecies pairs. However, studies of the primary reproductive barrier in house mice—hybrid male sterility—have been restricted to a single subspecies pair: Mus musculus musculus and Mus musculus domesticus. To provide a more complete characterization of reproductive isolation in house mice, we conducted an F2 intercross between wild-derived inbred strains from Mus musculus castaneus and M. m. domesticus. We identified autosomal and X-linked QTL associated with a range of hybrid male sterility phenotypes, including testis weight, sperm density, and sperm morphology. The pseudoautosomal region (PAR) was strongly associated with hybrid sterility phenotypes when heterozygous. We compared QTL found in this cross with QTL identified in a previous F2 intercross between M. m. musculus and M. m. domesticus and found three shared autosomal QTL. Most QTL were not shared, demonstrating that the genetic basis of hybrid male sterility largely differs between these closely related subspecies pairs. These results lay the groundwork for identifying genes responsible for the early stages of speciation in house mice. PMID:22554891

  6. A pentatricopeptide repeat-containing gene restores fertility to cytoplasmic male-sterile plants

    Microsoft Academic Search

    Stéphane Bentolila; Antonio A. Alfonso; Maureen R. Hanson

    2002-01-01

    Known in over 150 species, cytoplasmic male sterility is encoded by aberrant mitochondrial genes that prevent pollen development. The RNA- or protein-level expression of most of the mitochondrial genes encoding cytoplasmic male sterility is altered in the presence of one or more nuclear genes called restorers of fertility that suppress the male-sterile phenotype. Cytoplasmic male sterility\\/restorer systems have been proven

  7. Genetic Architecture of Hybrid Male Sterility in Drosophila: Analysis of Intraspecies Variation for

    E-print Network

    Markow, Therese

    Genetic Architecture of Hybrid Male Sterility in Drosophila: Analysis of Intraspecies Variation design, to perform quantitative trait locus (QTL) mapping analyses directly on F1 hybrid male sterility itself. We found that the genetic architecture of the polymorphism for hybrid male sterility (HMS

  8. Meiotic disturbances related to human male sterility J. M. LUCIANI, A. STAHL

    E-print Network

    Paris-Sud XI, Université de

    Meiotic disturbances related to human male sterility J. M. LUCIANI, A. STAHL Laboratoire d. Summary. The authors found an abnormal karyotype in 5 to 15 p. 100 of the cases of male sterility studied anomalies are one cause of human male sterility. These anomalies act in different ways : - They may cause

  9. GENETIC ARCHITECHTURE OF MALE STERILITY AND SEGREGATION DISTORTION IN DROSOPHILA PSEUDOOBSCURA BOGOTA-USA HYBRIDS

    E-print Network

    Nachman, Michael

    1 GENETIC ARCHITECHTURE OF MALE STERILITY AND SEGREGATION DISTORTION IN DROSOPHILA PSEUDOOBSCURA architecture underlying hybrid male sterility and segregation distortion between the Bogota and USA subspecies but not sufficient for both male sterility and segregation distortion in F1 hybrids between these subspecies

  10. Specific Expression in Reproductive Tissues and Fate of a Mitochondrial Sterility-Associated Protein in Cytoplasmic Male-Sterile Bean

    Microsoft Academic Search

    Andre R. Abad; Brian J. Mehrtens; Sally A. Mackenzie

    1995-01-01

    In common bean, cytoplasmic male sterility has been associated with a unique sequence found in the mitochondrial genome, designated pvs (for Phaseolus vulgaris sterility sequence). Within the pvs sequence, two open reading frames are encoded, ORF98 and ORF239. We have raised rabbit polyclonal antibodies against Pvs-ORF239 to evaluate the role of this putative male sterility-associated protein. Histological investigation of pollen

  11. Sport and the Sexually Abused Male Child

    ERIC Educational Resources Information Center

    Hartill, Mike

    2005-01-01

    Through feminist research in the study of sport, the issue of child sexual abuse has been driven onto the agenda of sports organisations, resulting in considerable practical reform (Brackenridge, 2001). However, the flip-side to this development is that the experience of sexually abused males has been largely ignored. In 1990, Struve claimed, "a…

  12. Double-stranded RNA and male sterility in rice

    Microsoft Academic Search

    B. Wang; Y. N. Li; X. W. Zhang; L. Hu; J. Z. Wang

    1990-01-01

    Double-stranded RNA (dsRNA) was isolated from rice Oryza sativa ssp. japonica, but not from other subspecies. The dsRNA has been found in all of the examined cytoplasmic male-sterile (CMS) lines of BT (Chinsurah Boro II)-type rice, but was not detected in their companionate maintainer lines. It is uniquely and positivley correlated with the CMS trait in BT-type rice. Recently, the

  13. Towards male sterility in Pinus radiata--a stilbene synthase approach to genetically engineer nuclear male sterility.

    PubMed

    Höfig, Kai P; Möller, Ralf; Donaldson, Lloyd; Putterill, Joanna; Walter, Christian

    2006-05-01

    A male cone-specific promoter from Pinus radiata D. Don (radiata pine) was used to express a stilbene synthase gene (STS) in anthers of transgenic Nicotiana tabacum plants, resulting in complete male sterility in 70% of transformed plants. Three plants were 98%-99.9% male sterile, as evidenced by pollen germination. To identify the stage at which transgenic pollen first developed abnormally, tobacco anthers from six different developmental stages were assayed microscopically. Following the release of pollen grains from tetrads, transgenic pollen displayed an increasingly flake-like structure, which gradually rounded up during the maturation process. We further investigated whether STS expression may have resulted in an impaired flavonol or sporopollenin formation. A specific flavonol aglycone stain was used to demonstrate that significant amounts of these substances were produced only in late stages of normal pollen development, therefore excluding a diminished flavonol aglycone production as a reason for pollen ablation. A detailed analysis of the exine layer by transmission electron microscopy revealed minor structural changes in the exine layer of ablated pollen, and pyrolysis-gas chromatography-mass spectroscopy indicated that the biochemistry of sporopollenin production was unaffected. The promoter-STS construct may be useful for the ablation of pollen formation in coniferous gymnosperms and male sterility may potentially be viewed as a prerequisite for the commercial use of transgenic conifers. PMID:17147639

  14. Sexually coercive male chimpanzees sire more offspring.

    PubMed

    Feldblum, Joseph T; Wroblewski, Emily E; Rudicell, Rebecca S; Hahn, Beatrice H; Paiva, Thais; Cetinkaya-Rundel, Mine; Pusey, Anne E; Gilby, Ian C

    2014-12-01

    In sexually reproducing animals, male and female reproductive strategies often conflict. In some species, males use aggression to overcome female choice, but debate persists over the extent to which this strategy is successful. Previous studies of male aggression toward females among wild chimpanzees have yielded contradictory results about the relationship between aggression and mating behavior. Critically, however, copulation frequency in primates is not always predictive of reproductive success. We analyzed a 17-year sample of behavioral and genetic data from the Kasekela chimpanzee (Pan troglodytes schweinfurthii) community in Gombe National Park, Tanzania, to test the hypothesis that male aggression toward females increases male reproductive success. We examined the effect of male aggression toward females during ovarian cycling, including periods when the females were sexually receptive (swollen) and periods when they were not. We found that, after controlling for confounding factors, male aggression during a female's swollen periods was positively correlated with copulation frequency. However, aggression toward swollen females was not predictive of paternity. Instead, aggression by high-ranking males toward females during their nonswollen periods was positively associated with likelihood of paternity. This indicates that long-term patterns of intimidation allow high-ranking males to increase their reproductive success, supporting the sexual coercion hypothesis. To our knowledge, this is the first study to present genetic evidence of sexual coercion as an adaptive strategy in a social mammal. PMID:25454788

  15. [Genetic study on two maize male sterile mutants obtained by space mutagenesis].

    PubMed

    Li, Yu-Ling; Yu, Yong-Liang; Liu, Yan-Xia; Li, Xue-Hui; Fu, Jia-Feng

    2007-06-01

    Two maize male sterile mutants were selected from the offspring of four maize inbred lines, which were carried into space by the Shenzhou spaceship 4. Their genetic characteristic and stability was analyzed in present study. Crosses were made between the male sterile plants and fertile plants from the same line, and other inbred lines with normal cytoplasm. The ratios of the sterile plants with the fertile plants in their F1, F2 generations, and their reciprocal backcross generations with the male sterile plants were calculated. The results showed that the characteristic in male sterility was stable in different years, different seasons and different locations, and was inheritable from generation to generation. This male sterile was controlled by a single nuclear recessive gene. Since no pollens or a few malformed pollens existed in the anther of the sterile plants, it was a completely sterile type. PMID:17650492

  16. Expression of Engineered Nuclear Male Sterility in Brassica napus (Genetics, Morphology, Cytology, and Sensitivity to Temperature).

    PubMed Central

    Denis, M.; Delourme, R.; Gourret, J. P.; Mariani, C.; Renard, M.

    1993-01-01

    A dominant genetic male sterility trait obtained through transformation in rapeseed (Brassica napus) was studied in the progenies of 11 transformed plants. The gene conferring the male sterility consists of a ribonuclease gene under the control of a tapetum-specific promoter. Two ribonuclease genes, RNase T1 and barnase, were used. The chimaeric ribonuclease gene was linked to the bialophos-resistance gene, which confers resistance to the herbicide phosphinotricine (PPT). The resistance to the herbicide was used as a dominant marker for the male sterility trait. The study presented here concerns three aspects of this engineered male sterility: genetics correlated with the segregation of the T-DNA in the progenies; expression of the male sterility in relation to the morphology and cytology of the androecium; and stability of the engineered male sterility under different culture conditions. Correct segregation, 50% male-sterile, PPT-resistant plants, and 50% male-fertile, susceptible plants were observed in the progeny of seven transformants. The most prominent morphological change in the male-sterile flowers was a noticeable reduction in the length of the stamen filament. The first disturbances of microsporogenesis were observed from the free microspore stage and were followed by a simultaneous degeneration of microspore and tapetal cell content. At anthesis, the sterile anthers contained only empty exines. In some cases, reversion to fertility of male-sterile plants has been observed. Both ribonuclease genes are susceptible to instability. Instability of the RNase T1-male sterility trait increased at temperatures higher than 25[deg] C. Our results do not allow us to confirm this observation for the barnase male-sterile plants. However, the male-sterile plants of the progeny of two independent RNase T1 transformants were stably male sterile under all conditions studied. PMID:12231785

  17. Expression of sunflower cytoplasmic male sterility-associated open reading frame, orf H522 induces male sterility in transgenic tobacco plants

    Microsoft Academic Search

    Narasimha Rao Nizampatnam; Harinath Doodhi; Yamini Kalinati Narasimhan; Sujatha Mulpuri; Dinesh Kumar Viswanathaswamy

    2009-01-01

    Sterility in the universally exploited PET1-CMS system of sunflower is associated with the expression of orfH522, a novel mitochondrial gene. Definitive evidence that ORFH522 is directly responsible for male sterility is lacking.\\u000a To test the hypothesis that ORFH522 is sufficient to induce male sterility, a set of chimeric constructs were developed. The\\u000a cDNA of orfH522 was cloned in-frame with yeast

  18. ORIGINAL PAPER Innate responses to male sexual harassment

    E-print Network

    Pilastro, Andrea

    shoals. They also approach other males to promote male competition, and when males differ in size of male­male competition and shoaling on the amount of male sexual harassment. In the third groupORIGINAL PAPER Innate responses to male sexual harassment in female mosquitofish Marco Dadda

  19. Sexual function of the ageing male.

    PubMed

    Corona, Giovanni; Rastrelli, Giulia; Maseroli, Elisa; Forti, Gianni; Maggi, Mario

    2013-08-01

    With the progressive increase in the proportion of older people, there is an increasing interest in characterizing the modifications of sexual health and the effect of its perturbations as a function of the aging process. The aim of this review is to summarize the available evidence regarding the age-dependent modifications of male sexual function and their interaction with general health and age-dependent modification of endocrine function. Elderly patients are often affected by multiple organic diseases which can interfere with sexual function. Despite this evidence, several studies have indicated that, with advancing age, normal erections are not an absolute prerequisite to remain sexually active. Good physical health, the availability of a partner, and a regular and stable pattern of sexual activity earlier in life predict the maintenance of sexual activity in old age. Conversely, there are no convincing data that hormonal changes, associated with aging, have a primary role in underlying changes in sexual function in healthy aging men. Nonetheless, sexual dysfunctions especially in elderly people are poor investigated. Asking about sexual health remains difficult or embarrassing for many primary care physicians. In addition, many patients find it difficult to raise sexual issues with their doctor. This situation often results in sexual issues not being adequately addressed thus resulting in depression, social withdrawal and delayed diagnosis of underlying medical conditions often resulting in forthcoming cardiovascular events. Education and permission from a health care professional may help to alter such misconceptions. Information from physicians regarding normal age-related changes in sexuality and encouragement, together with advice on how to continue meaningful sexual relations, may play a key role in altering such negative attitudes. PMID:24054932

  20. Identification of molecular markers linked to a new nuclear male-sterility gene ms7 in sunflower (Helianthus annuus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nuclear male sterility (NMS) is an important alternative system to the cytoplasm male sterility (CMS) in hybrid breeding programs because of its stable male sterility and abundant available restorer resources. For sunflower (Helianthus annuus L.), NMS 89-552, a nuclear male-sterile mutant induced by...

  1. Sexual identity and HIV: The male prostitute

    Microsoft Academic Search

    Jacqueline Boles; Kirk W. Elifson

    1994-01-01

    We examined the relationships among sexual self?identity, sexual and drug use behaviors, and human immunodeficiency virus (HIV) infection among a sample of 224 male street prostitutes. Structured interviews were administered, and blood samples were collected and tested for HIV, syphilis, and hepatitis B. The sample included 17.9% homosexual, 46.4% heterosexual, and 35.7% bisexually identified men. Congruence between the prostitutes’ non?paid

  2. Sexuality of male-to-female transsexuals.

    PubMed

    Veale, Jaimie F; Clarke, Dave E; Lomax, Terri C

    2008-08-01

    Blanchard's (J Nerv Ment Dis 177:616-623, 1989) theory of autogynephilia suggests that male-to-female transsexuals can be categorized into different types based on their sexuality. Little previous research has compared the sexuality of male-to-female transsexuals to biological females. The present study examined 15 aspects of sexuality among a non-clinical sample of 234 transsexuals and 127 biological females, using either an online or a paper questionnaire. The results showed that, overall, transsexuals tended to place more importance on partner's physical attractiveness and reported higher scores on Blanchard's Core Autogynephilia Scale than biological females. In addition, transsexuals classified as autogynephilic scored significantly higher on Attraction to Feminine Males, Core Autogynephilia, Autogynephilic Interpersonal Fantasy, Fetishism, Preference for Younger Partners, Interest in Uncommitted Sex, Importance of Partner Physical Attractiveness, and Attraction to Transgender Fiction than other transsexuals and biological females. In accordance with Blanchard's theory, autogynephilia measures were positively correlated to Sexual Attraction to Females among transsexuals. In contrast to Blanchard's theory, however, those transsexuals classified as autogynephilic scored higher on average on Sexual Attraction to Males than those classified as non-autogynephilic, and no transsexuals classified as autogynephilic reported asexuality. PMID:18299976

  3. Genetic analysis of male fertility restoration in wild cytoplasmic male sterility G of beet

    Microsoft Academic Search

    Pascal Touzet; Nathalie Hueber; Alexandra Bürkholz; Stephen Barnes; Joël Cuguen

    2004-01-01

    Cytoplasmic male sterility (CMS) has been used in the breeding of sugar beet for decades but is also more generally an important feature of the reproductive system in its wild relative, Beta vulgaris ssp. maritima. Among the several CMSs found in wild populations, the G CMS is a mitochondrial variant of the respiratory chain. The segregants derived from a cross

  4. Sexual behaviour and sexually transmitted disease patterns in male homosexuals.

    PubMed Central

    Willcox, R R

    1981-01-01

    Male homosexual behaviour is not simply either "active" or "passive", since penile-anal, mouth-penile, and hand-anal sexual contact is usual for both partners, and mouth-anal contact is not infrequent. A simplified method for recording sexual behaviour--a "sexual behaviour record (SBR)"--can be of value in determining the sites to be investigated and as a basis for further epidemiological questioning. Mouth-anal contact is the reason for the relatively high incidence of diseases caused by bowel pathogens in male homosexuals. Trauma may encourage the entry of micro-organisms and thus lead to primary syphilitic lesions occurring in the anogenital area. Similarly, granuloma inguinale, condylomata acuminata, and amoebiasis may be spread from the bowel of the passive homosexual contact. In addition to sodomy, trauma may be caused by foreign bodies, including stimulators of various kinds, penile adornments, and prostheses. Images PMID:6894558

  5. Fertility Compensation of Cornerstone Male Sterility of Wheat by Rye

    PubMed Central

    Hossain, M. A.; Driscoll, C. J.

    1983-01-01

    The genome of rye is known to compensate for the lost male-fertility gene(s) of wheat chromosome arm 4A? in the Cornerstone male-sterility mutant. A search for the rye chromosome(s) involved in this compensation showed that chromosomes 2R and 4R are responsible. Only the short arms of these two chromosomes are the operative ones. Chromosome arm 4RS compensates in an erratic way, whereas 2RS compensates in a full and consistent way. The entire chromosome 2R compensates less well than the 2RS telocentric which reflects an antifertility factor(s) on 2RL. This may be a specific expression of the 2R genes for poor vigor which are located on only the long arm. 2RS will be a valuable piece of chromatin for the XYZ system of producing hybrid wheat. PMID:17246128

  6. Fertility compensation of cornerstone male sterility of wheat by rye.

    PubMed

    Hossain, M A; Driscoll, C J

    1983-05-01

    The genome of rye is known to compensate for the lost male-fertility gene(s) of wheat chromosome arm 4Aalpha in the Cornerstone male-sterility mutant. A search for the rye chromosome(s) involved in this compensation showed that chromosomes 2R and 4R are responsible. Only the short arms of these two chromosomes are the operative ones. Chromosome arm 4RS compensates in an erratic way, whereas 2RS compensates in a full and consistent way. The entire chromosome 2R compensates less well than the 2RS telocentric which reflects an antifertility factor(s) on 2RL. This may be a specific expression of the 2R genes for poor vigor which are located on only the long arm. 2RS will be a valuable piece of chromatin for the XYZ system of producing hybrid wheat. PMID:17246128

  7. Characterization of three male-sterile mutants of Arabidopsis thaliana exhibiting alterations in meiosis

    Microsoft Academic Search

    Brenda N. Peirson; Heather A. Owen; Kenneth A. Feldmann; Christopher A. Makaroff

    1996-01-01

    Male-sterile mutants are being studied to deepen our understanding of the complex processes of microsporogenesis and microgametogenesis. Due to difficulties associated with isolating the mutated gene, there is currently very little molecular information on the defects responsible for male sterility. As a first step in utilizing male-sterile mutants to better understand the bio-chemical and molecular processes that control pollen development,

  8. Cytoplasmic Male Sterility in Mimulus hybrids has Pleiotropic Effects on Corolla and Pistil Traits Camille M. Barr and Lila Fishman

    E-print Network

    Fishman, Lila

    Cytoplasmic Male Sterility in Mimulus hybrids has Pleiotropic Effects on Corolla and Pistil Traits between cytonuclear anther sterility and other floral traits in Mimulus hybrids. Male-sterile flowers had that male-sterile plants produced ~20 seeds per flower more than fertile sibling after supplemental

  9. A chimaeric ribonuclease-inhibitor gene restores fertility to male sterile plants

    Microsoft Academic Search

    Celestina Mariani; Veronique Gossele; Marc De Beuckeleer; Marc De Block; Robert B. Goldberg; Willy De Greef; Jan Leemans

    1992-01-01

    Male fertility was restored to genetically engineered male sterile oilseed rape plants. Male sterile plants that express a chimaeric ribonuclease gene in the anther tapetal cell layer were crossed with male fertile plants that were transformed with a chimaeric tapetal-cell-specific ribonuclease-inhibitor gene. F1 progeny expressing both genes are restored to male fertility by the suppression of cytotoxic ribonuclease activity in

  10. Scoring men: vasectomies and the totemic illusion of male sexuality in Oaxaca.

    PubMed

    Gutmann, Matthew C

    2005-03-01

    This paper discusses research on men's reproductive health and sexuality in Oaxaca, Mexico, and specifically why some men there choose to be sterilized. Men who opt for vasectomies do so after considering numerous cultural, historical, physiological, commercial, and other concerns. Men and women in Oaxaca negotiate certain cultural folk beliefs about supposed male sexual desires and practices before arriving at the decision to get the operation. Vasectomy as a method of birth control is chosen despite folk beliefs that take the form of a totemic illusion which treats male sexuality as naturalized, something fixed, and as entirely distinct from female sexuality. Among its many consequences, this totemic illusion serves to conceal inequalities in the sphere of reproductive health and sexuality in relation to contraception. PMID:16108204

  11. Ogura cytoplasmic male-sterility (CMS)-associated orf138 is translated into a mitochondrial membrane polypeptide in male-sterile Brassica cybrids

    Microsoft Academic Search

    Mathilde Grelon; Françoise Budar; Sandrine Bonhomme; Georges Pelletier

    1994-01-01

    Transcription of a putative mitochondrial gene (orf138) has previously been correlated with Ogura cytoplasmic male-sterility (CMS) in rapeseed cybrids. In this paper, studies performed on a Brassica cybrid with a different organization of the orf138 locus confirm this association. We also show that mitochondria isolated from male-sterile rapeseed plants synthesize a polypeptide of 19 kDa, which is absent in fertile

  12. Mitochondrial genome diversity in connection with male sterility in Allium schoenoprasum L

    Microsoft Academic Search

    T. Engelke; T. Tatlioglu

    2000-01-01

    Mitochondrial genome diversity in chives (Allium schoenoprasum L.) was investigated with respect to different forms of male sterility. Cytoplasmic male-sterile (CMS) and restored genotypes\\u000a of the known CMS system, compared to plants of the wi-, the st1- and the st2-sterility types and additional fertile plants of different origin were examined by means of RFLP analyses using mitochondrial\\u000a gene probes. Besides

  13. Induction of male sterility in plants by a chimaeric ribonuclease gene

    Microsoft Academic Search

    Celestina Mariani; Marc De Beuckeleer; Jessie Truettner; Jan Leemans; Robert B. Goldberg

    1990-01-01

    Chimaeric ribonuclease genes that are expressed in the anthers of transformed tobacco and oilseed rape plants were constructed. Chimaeric ribonuclease gene expression within the anther selectively destroys the tapetal cell layer that surrounds the pollen sac, prevents pollen formation, and leads to male sterility. These nuclear male sterility genes should facilitate the production of hybrid seed in various crop plants.

  14. The population genetics of gynodioecy with cytoplasmic-genic male-sterility

    Microsoft Academic Search

    D Charlesworth; F R Ganders

    1979-01-01

    Two models of gynodioecy controlled by cytoplasmic factors and nuclear genes are studied. In one model, there is a male-sterility determining cytoplasm which produces its effect only in the absence of a restorer allele at a nuclear locus. In the other model, either the cytoplasmic factor or the nuclear gene can produce male-sterility independently of the other. Neither model permits

  15. Mitochondrial atp6 transcript editing during microgametogenesis in male-sterile sorghum

    Microsoft Academic Search

    Daryl Pring; Hoang Tang

    2001-01-01

    A marked reduction of mitochondrial atp6 transcript-editing capability in sorghum anthers and pollen has been invoked as a factor in the loss of viability of male gametophytes in lines carrying the IS1112C male-sterile cytoplasm. We initiated a systematic examination of transcript editing of sorghum atp6 during microgametogenesis, from microspores through pollen, in two sets of male-fertile and near-isogenic, male-sterile lines.

  16. Fluctuating asymmetry, metabolic rate and sexual selection in human males

    Microsoft Academic Search

    J. T. Manning; K. Koukourakis; D. A. Brodie

    1997-01-01

    Fluctuating asymmetry (FA), a measure of developmental stability, may be important in human sexual selection, that is in mate choice and male-male competition. It is shown that in males (but not in females) resting metabolic rate (RMR) is positively related to FA. This is explained in terms of the balanced energy equation of males. Sexual selection for large body size

  17. The control of male sexual responses.

    PubMed

    Courtois, Frédérique; Carrier, Serge; Charvier, Kathleen; Guertin, Pierre A; Journel, Nicolas Morel

    2013-01-01

    Male sexual responses are reflexes mediated by the spinal cord and modulated by neural circuitries involving both the peripheral and central nervous system. While the brain interact with the reflexes to allow perception of sexual sensations and to exert excitatory or inhibitory influences, penile reflexes can occur despite complete transections of the spinal cord, as demonstrated by the reviewed animal studies on spinalization and human studies on spinal cord injury. Neurophysiological and neuropharmacological substrates of the male sexual responses will be discussed in this review, starting with the spinal mediation of erection and its underlying mechanism with nitric oxide (NO), followed by the description of the ejaculation process, its neural mediation and its coordination by the spinal generator of ejaculation (SGE), followed by the occurrence of climax as a multisegmental sympathetic reflex discharge. Brain modulation of these reflexes will be discussed through neurophysiological evidence involving structures such as the medial preoptic area of hypothalamus (MPOA), the paraventricular nucleus (PVN), the periaqueductal gray (PAG), and the nucleus para-gigantocellularis (nPGI), and through neuropharmacological evidence involving neurotransmitters such as serotonin (5-HT), dopamine and oxytocin. The pharmacological developments based on these mechanisms to treat male sexual dysfunctions will complete this review, including phosphodiesterase (PDE-5) inhibitors and intracavernous injections (ICI) for the treatment of erectile dysfunctions (ED), selective serotonin reuptake inhibitor (SSRI) for the treatment of premature ejaculation, and cholinesterase inhibitors as well as alpha adrenergic drugs for the treatment of anejaculation and retrograde ejaculation. Evidence from spinal cord injured studies will be highlighted upon each step. PMID:23360268

  18. Reduction in sea lamprey hatching success due to release of sterilized males

    USGS Publications Warehouse

    Bergstedt, R.A.; McDonald, R.B.; Twohey, M.B.; Mullett, K.M.; Young, R.J.; Heinrich, J.W.

    2003-01-01

    Male sea lampreys (Petromyzon marinus), sterilized by injection with bisazir, were released in Lake Superior tributaries from 1991 to 1996 and exclusively in the St. Marys River (the outflow from Lake Superior to Lake Huron) since 1997 as an alternative to chemical control. To determine effectiveness in reducing reproductive potential through the time of hatch, males were observed on nests and egg viability was determined in nests in selected Lake Superior tributaries and the St. Marys River. The proportions of sterilized males observed on nests were not significantly different than their estimated proportion in the population for all streams and years combined or for the St. Marys River alone. It was concluded that sterilized males survive, appear on the spawning grounds, and nest at near their estimated proportion in the population. There was a significant reduction in egg viability corresponding with release of sterilized males for all streams and years combined or for the St. Marys River alone. In the St. Marys River from 1993 to 2000, the percent reduction in egg viability was significantly correlated with the observed proportion of sterile males on nests. It was further concluded that sterilized males remain sterile through nesting and attract and mate with females. Reduction in reproductive potential in the St. Marys River due to both removal of females by traps and sterile-male-release ranged from 34 to 92% from 1993 to 2001 and averaged 64%. From 1999 to 2001, when the program stabilized, reductions ranged from 71 to 92% and averaged 81%. The current release of sterile males in the St. Marys River effectively reduced reproductive potential through the time of hatch and did so near theoretical levels based on numbers released, estimates of population size, and the assumptions of full sterility and competitiveness.

  19. Respiration in Cells and Mitochondria of Male-Fertile and Male-Fertile and Male-Sterile Nicotiana spp. 1

    PubMed Central

    Håkansson, Gunilla; Glimelius, Kristina; Bonnett, Howard T.

    1990-01-01

    Three cytoplasmic male-sterile Nicotiana cultivars together with corresponding male-fertile progenitors and restored lines were investigated in order to find possible correlations between respiratory characteristics and male sterility. Oxygen consumption measurements were performed on cells from suspension cultures as well as on mitochondria isolated from green leaves. Inhibitors, which have been reported to specifically block either the cytochrome (KCN) or the alternative (propyl gallate and sali-cylhydroxamic acid [SHAM] respiratory pathways, were used in order to measure the capacity and activity of the two pathways. One of the inhibitors, SHAM, was found unsuitable to measure the activity of the alternative pathway due to the lack of specificity of SHAM for this pathway. A great difference in the capacity of the alternative pathway was detected between the two types of cell materials tested. Mitochondria isolated from green leaves showed a capacity of the alternative pathway of 5 to 20% of total mitochondrial repiration, while the capacity of cells from suspension cultures generally ranged from 50 to 80%. In addition to this, in organello synthesis of mitochondrial proteins revealed differences between mitochondria isolated from green leaves and from cell suspensions. No correlation, however, could be found between respiratory characteristics and male sterility. Images Figure 1 Figure 2 PMID:16667475

  20. Sexual Dysfunction in Males: Significance of Adverse Childhood Experiences.

    ERIC Educational Resources Information Center

    Kinzl, Johann F.; And Others

    1996-01-01

    A survey of 301 male college students found that occasional sexual dysfunction was frequent in young male adults, and long-lasting adverse familial relationships to attachment figures were more influential in later sexual dysfunction than were childhood sexual abuse experiences. (Author/DB)

  1. Hybrid male sterility in rice controlled by interaction between divergent alleles of two adjacent genes

    PubMed Central

    Long, Yunming; Zhao, Lifeng; Niu, Baixiao; Su, Jing; Wu, Hao; Chen, Yuanling; Zhang, Qunyu; Guo, Jingxin; Zhuang, Chuxiong; Mei, Mantong; Xia, Jixing; Wang, Lan; Wu, Haibin; Liu, Yao-Guang

    2008-01-01

    Sterility is common in hybrids between divergent populations, such as the indica and japonica subspecies of Asian cultivated rice (Oryza sativa). Although multiple loci for plant hybrid sterility have been identified, it remains unknown how alleles of the loci interact at the molecular level. Here we show that a locus for indica-japonica hybrid male sterility, Sa, comprises two adjacent genes, SaM and SaF, encoding a small ubiquitin-like modifier E3 ligase-like protein and an F-box protein, respectively. Most indica cultivars contain a haplotype SaM+SaF+, whereas all japonica cultivars have SaM?SaF? that diverged by nucleotide variations in wild rice. Male semi-sterility in this heterozygous complex locus is caused by abortion of pollen carrying SaM?. This allele-specific gamete elimination results from a selective interaction of SaF+ with SaM?, a truncated protein, but not with SaM+ because of the presence of an inhibitory domain, although SaM+ is required for this male sterility. Lack of any one of the three alleles in recombinant plants does not produce male sterility. We propose a two-gene/three-component interaction model for this hybrid male sterility system. The findings have implications for overcoming male sterility in inter-subspecific hybrid rice breeding. PMID:19033192

  2. [Inheritance of reversions to male fertility in male-sterile sorghum hybrids with 9E cytoplasm male sterility induced by environmental conditions].

    PubMed

    Elkonin, L A; Gerashchenkov, G A; Domanina, I V; Rozhnova, N A

    2015-03-01

    Heritable phenotypic alterations occurring during plant ontogenesis under the influence of environmental factors are among the most intriguing genetic phenomena. It was found that male-sterile sorghum hybrids in the 9E cytoplasm from the F1 and F2 generations, which were obtained by crossing CMS lines with different fertile lines grown in field conditions, were transferred to greenhouse produce fertile tillers. Lines created by the self-pollination of revertant tillers exhibit complete male fertility upon cultivation under various environments (in the field, Tdry plot,(y) Tirrigated plot(y)). In a number of test-crosses of revertants to CMS lines in the 9E cytoplasm, restoration of male fertility in F1 hybrids was found, indicating that revertants possess functional fertility-restoring genes. A high positive correlation was found between the fertility level of the test-cross hybrids and the hydrothermal coefficient (the ratio of the sum of precipitation to the sum of temperatures) during the booting stage and pollen maturation (r = 0.75...0.91; P<0.01), suggesting that a high level of plant water availability is needed for the expression of fertility-restoring genes of revertants. These data show that the fertility-restoring genes for the 9E cytoplasm are dominant in conditions of high water availability and recessive in drought conditions; reversions to male fertility are due to up-regulation of fertility-restoring genes by a high level of water availability. Comparative MSAP-analysis of DNA of male-sterile and male-fertile test-cross hybrids using HpaII/MspI restrictases and primers to polygalacturonase gene ADPG2, which is required for cell separation during reproductive development, and gene MYB46, the transcription factor regulating secondary wall biosynthesis, revealed differences in the number and the length of amplified fragments. Changes in the methylation of these genes in conditions of drought stress are apparently the reason for male sterility of sorghum hybrids in the 9E cytoplasm. These data demonstrate that methylation of nuclear genes in sterility-inducing cytoplasm may be one of mechanisms causing the CMS phenomenon. PMID:26027370

  3. Post-copulatory sexual selection and sexual conflict in the evolution of male pregnancy

    E-print Network

    Sorenson, Michael

    LETTERS Post-copulatory sexual selection and sexual conflict in the evolution of male pregnancy Kimberly A. Paczolt1 & Adam G. Jones1 Male pregnancy in seahorses, pipefishes and sea dragons (family-copulatory sexual selection within broods and for trade-offs between successive male pregnancies as functions

  4. Meiotic effects in chromosomally derived male sterility of mice A. G. SEARLE, C. V. BEECHEY E. P. EVANS

    E-print Network

    Paris-Sud XI, Université de

    Meiotic effects in chromosomally derived male sterility of mice A. G. SEARLE, C. V. BEECHEY E. P. Summary. Much sterility in male (though not in female) mice can be related to the pre- sence of specific tertiary trisomic mice, which are also male-sterile as a rule. Mammalian spermatogenesis is a complex

  5. Note on the appearance of a new nucleocyto-plasmic male sterility in Vicia faba after muta-

    E-print Network

    Boyer, Edmond

    Note on the appearance of a new nucleocyto- plasmic male sterility in Vicia faba after muta, B.P. 29, F35650 Le Rheu SUMMARY A new cytoplasm appeared in a nucleo-cytoplasmic male sterile line behaved differently when crossed with genomes that maintain or restore the 447 male sterility. The new

  6. The male sterile 8 mutation of maize disrupts the temporal progression of the transcriptome and results in the

    E-print Network

    Kay, Mark A.

    The male sterile 8 mutation of maize disrupts the temporal progression of the transcriptome proliferation, cell fate acquisition and the start of meiosis. Although many male-sterile mutants disrupt (Goldberg et al., 1993). Nuclear male sterility has been reported in many flowering plants, and in most

  7. Identification and mapping of RAPD and RFLP markers linked to a fertility restorer gene for a new source of cytoplasmic male sterility in Beta vulgaris ssp. maritima

    Microsoft Academic Search

    V. Laporte; D. Merdinoglu; P. Saumitou-Laprade; G. Butterlin; P. Vernet; J. Cuguen

    1998-01-01

    The present study shows that the recently described mitochondrial H haplotype is associated with cytoplasmic male-sterility\\u000a (CMS). This new source of CMS appears to be different from the mitotype E-associated CMS most frequently found in natural\\u000a populations. A mitotype H progeny with a sexual phenotype segregation was used to identify a gene restoring male fertility\\u000a (R1H?). Using bulk segregant analysis

  8. Hybrid Male Sterility in Rice Is Due to Epistatic Interactions with a Pollen Killer Locus

    PubMed Central

    Kubo, Takahiko; Yoshimura, Atsushi; Kurata, Nori

    2011-01-01

    In intraspecific crosses between cultivated rice (Oryza sativa) subspecies indica and japonica, the hybrid male sterility gene S24 causes the selective abortion of male gametes carrying the japonica allele (S24-j) via an allelic interaction in the heterozygous hybrids. In this study, we first examined whether male sterility is due solely to the single locus S24. An analysis of near-isogenic lines (NIL-F1) showed different phenotypes for S24 in different genetic backgrounds. The S24 heterozygote with the japonica genetic background showed male semisterility, but no sterility was found in heterozygotes with the indica background. This result indicates that S24 is regulated epistatically. A QTL analysis of a BC2F1 population revealed a novel sterility locus that interacts with S24 and is found on rice chromosome 2. The locus was named Epistatic Factor for S24 (EFS). Further genetic analyses revealed that S24 causes male sterility when in combination with the homozygous japonica EFS allele (efs-j). The results suggest that efs-j is a recessive sporophytic allele, while the indica allele (EFS-i) can dominantly counteract the pollen sterility caused by S24 heterozygosity. In summary, our results demonstrate that an additional epistatic locus is an essential element in the hybrid sterility caused by allelic interaction at a single locus in rice. This finding provides a significant contribution to our understanding of the complex molecular mechanisms underlying hybrid sterility and microsporogenesis. PMID:21868603

  9. Cytoplasmic male sterility contributes to hybrid incompatibility between subspecies of Arabidopsis lyrata.

    PubMed

    Aalto, Esa A; Koelewijn, Hans-Peter; Savolainen, Outi

    2013-10-01

    In crosses between evolutionarily diverged populations, genomic incompatibilities may result in sterile hybrids, indicating evolution of reproductive isolation. In several plant families, crosses within a population can also lead to male sterile progeny because of conflict between the maternally and biparentally inherited genomes. We examined hybrid fertility between subspecies of the perennial outcrossing self-incompatible Lyrate rockcress (Arabidopsis lyrata) in large reciprocal F2 progenies and three generations of backcrosses. In one of the reciprocal F2 progenies, almost one-fourth of the plants were male-sterile. Correspondingly, almost one-half of the plants in one of the four reciprocal backcross progenies expressed male sterility. In an additional four independent F2 and backcross families, three segregated male sterility. The observed asymmetrical hybrid incompatibility is attributable to male sterility factors in one cytoplasm, for which the other population lacks effective fertility restorers. Genotyping of 96 molecular markers and quantitative trait locus mapping revealed that only 60% of the plants having the male sterile cytoplasm and lacking the corresponding restorers were phenotypically male-sterile. Genotyping data showed that there is only one restorer locus, which mapped to a 600-kb interval at the top of chromosome 2 in a region containing a cluster of pentatricopeptide repeat genes. Male fertility showed no trade-off with seed production. We discuss the role of cytoplasm and genomic conflict in incipient speciation and conclude that cytoplasmic male sterility-lowering hybrid fitness is a transient effect with limited potential to form permanent reproductive barriers between diverged populations of hermaphrodite self-incompatible species. PMID:23935000

  10. Molecular diversity of male sterility inducing and male-fertile cytoplasms in the genus Helianthus

    Microsoft Academic Search

    R. Horn

    2002-01-01

    The organisation of mtDNA was investigated for 28 sources of cytoplasmic male sterility (CMS) and a fertile line (normal cytoplasm)\\u000a of Helianthus annuus by Southern hybridisation. In addition to nine known mitochondrial genes (atp6, atp9, cob, coxI, coxII, coxIII, 18S, 5S and nd5) three probes for the open reading frames in the rearranged area of PET1, orfH522, orfH708 and orfH873,

  11. A fertile revertant from petaloid cytoplasmic male-sterile carrot has a rearranged mitochondrial genome

    Microsoft Academic Search

    A. Chahal; H. S. Sidhu; D. J. Wolyn

    1998-01-01

    A spontaneously derived fertile plant was recovered from a petaloid cytoplasmic male-sterile (CMS) carrot inbred line. Genetic\\u000a analysis indicated a single nuclear gene was responsible for the restoration to fertility. Within a family segregating for\\u000a the nuclear restorer in combination with the sterility-inducing cytoplasm, fertile plants were recovered that could not restore\\u000a fertility when crossed to sterile genotypes. Genetic analysis

  12. Genetics of Reproductive Isolation in the Drosophila simulans Clade: Complex Epistasis Underlying Hybrid Male Sterility

    Microsoft Academic Search

    Eric L. Cabot; Andrew W. Davis; Norman A. Johnson; Chung-I Wu

    We have analyzed the sterility associated with introgressions of the distal one-fourth of the X chrc- mosome from either Drosophila mauritiana or Drosophila sechellia into the genome of Drosophila simu- lans using a series of visible and DNA markers. Because in Drosophila hybrids, male sterility is usually complete and is often tightly linked with each of several markers used in

  13. Genomics and Transcriptomics of Hybrid Male Sterility Assessed in Multiple Interspecies Feline Breeds

    E-print Network

    Davis, Brian W

    2013-05-13

    Hybrid male sterility (HMS) is typically the first mechanism fortifying reproductive isolation resulting from genomic incompatibilities. Three interspecies feline breeds derived from domestic cat crosses to wild cat species (Asian leopard cat...

  14. Strikingly, Wolbachia also induce a form of male sterility, a phenomenon called

    E-print Network

    Johnson, Kevin P.

    Strikingly, Wolbachia also induce a form of male sterility, a phenomenon called cytoplasmic incompatibility (CI), which is widespread in arthropods. CI results in embryonic mortality when males infected the eggs with an antidote, protecting them from the action of a poison produced in germline of the males

  15. Sexual size dimorphism in the American rubyspot: male body size predicts male competition and mating success

    Microsoft Academic Search

    M. A. Serrano-Meneses; A. Córdoba-Aguilar; V. Méndez; S. J. Layen; T. Székely

    2007-01-01

    Sexual differences in body size are widespread among animals, and various explanations for the evolution and maintenance of sexual size dimorphism have been proposed. We investigated the effects of sexual selection and fecundity selection on the sizes of males and females, respectively, in American rubyspots, Hetaerina americana. Males are larger than females and have large red spots at the base

  16. Characterization of pearl millet mitochondrial DNA fragments rearranged by reversion from cytoplasmic male sterility to fertility

    Microsoft Academic Search

    R. L. Smith; M. K. U. Chowdhury

    1991-01-01

    Cloned pearl millet [Pennisetum glaucum (L.) R. Br.] mitochondrial (mt) DNA fragments rearranged by spontaneous reversion from cytoplasmic male sterility (cms) to fertility were characterized by restriction mapping, hybridization with maize mt genes, and transcription analyses. The clones characterized were a 4.7-kb fragment found only in the male-sterile cytoplasm and lost upon reversion to fertility, a 10.9-kb fragment found in

  17. Premature Dissolution of the Microsporocyte Callose Wall Causes Male Sterility in Transgenic Tobacco

    Microsoft Academic Search

    Dawn Worrall; Diane L. Hird; Wyatt Paul; John Draper

    1992-01-01

    Male sterility in a petunia cytoplasmic male sterile line has been attributed to the early appearance of active callase, a P-1,3-glucanase, in the anther locule. This leads to premature dissolution of the callose walls surrounding the microsporogenous cells. We have mimicked this aspect of the petunia line in transgenic tobacco by engineering the secretion of a modified pathogenesis-related vacuolar P-1,3-glucanase

  18. A Moricandia arvensis– based cytoplasmic male sterility and fertility restoration system in Brassica juncea

    Microsoft Academic Search

    S. Prakash; P. B. Kirti; S. R. Bhat; K. Gaikwad; V. D. Kumar; V. L. Chopra

    1998-01-01

    A cytoplasmic male-sterility system has been developed in mustard (Brassica juncea) following repeated backcrossings of the somatic hybrid Moricandia arvensis (2n=28, MM)+B. juncea (2n=36, AABB), carrying mitochondria and chloroplasts from M. arvensis, to Brassica juncea. Cytoplasmic male-sterile (CMS) plants are similar to normal B. juncea; however, the leaves exhibit severe chlorosis resulting in delayed flowering. Flowers are normal with slender,

  19. The influence of sexual selection and male agility on sexual size dimorphism in bustards (Otididae)

    E-print Network

    The influence of sexual selection and male agility on sexual size dimorphism in bustards (Otididae; published online 17 February 2006; MS. number: 8276R) Bustards vary considerably in sexual size dimorphism polygynous mating systems in bustards were associated with relatively larger males. Second, our results

  20. Workable male sterility systems for hybrid rice: Genetics, biochemistry, molecular biology, and utilization.

    PubMed

    Huang, Jian-Zhong; E, Zhi-Guo; Zhang, Hua-Li; Shu, Qing-Yao

    2014-12-01

    The exploitation of male sterility systems has enabled the commercialization of heterosis in rice, with greatly increased yield and total production of this major staple food crop. Hybrid rice, which was adopted in the 1970s, now covers nearly 13.6 million hectares each year in China alone. Various types of cytoplasmic male sterility (CMS) and environment-conditioned genic male sterility (EGMS) systems have been applied in hybrid rice production. In this paper, recent advances in genetics, biochemistry, and molecular biology are reviewed with an emphasis on major male sterility systems in rice: five CMS systems, i.e., BT-, HL-, WA-, LD- and CW- CMS, and two EGMS systems, i.e., photoperiod- and temperature-sensitive genic male sterility (P/TGMS). The interaction of chimeric mitochondrial genes with nuclear genes causes CMS, which may be restored by restorer of fertility (Rf) genes. The PGMS, on the other hand, is conditioned by a non-coding RNA gene. A survey of the various CMS and EGMS lines used in hybrid rice production over the past three decades shows that the two-line system utilizing EGMS lines is playing a steadily larger role and TGMS lines predominate the current two-line system for hybrid rice production. The findings and experience gained during development and application of, and research on male sterility in rice not only advanced our understanding but also shed light on applications to other crops. PMID:26055995

  1. Pilot field trials with Aedes albopictus irradiated sterile males in Italian urban areas.

    PubMed

    Bellini, R; Medici, A; Puggioli, A; Balestrino, F; Carrieri, M

    2013-03-01

    The pilot field studies here presented are part of a long-term research program aimed to develop a cost-effective sterile insect technique (SIT) methodology to suppress Aedes albopictus (Skuse) populations. Aedes albopictus is a mosquito species mainly developing in man-made containers and with an island-like urban and suburban distribution. These two features make the application of the sterile insect technique a possible control strategy. Five trials have been performed in three small towns from 2005 to 2009 (Emilia-Romagna region, northern Italy). Reared male pupae, sexed by a sieving technique allowing the recovery of approximately 26-29% of males, were exposed to gamma rays and immediately released in the field. Adult population density was estimated based on a weekly monitoring of egg density in the ovitraps, whereas induced sterility was estimated by measuring the hatching percentage of weekly collected eggs in SIT and control areas. Results showed that sterile males released at the rate of 896-1,590 males/ha/wk induced a significant sterility level in the local population. In addition, when the sterility level achieved values in the range of 70-80%, a similar reduction also was found for the egg density in the ovitraps. We could estimate that the minimum egg sterility value of 81% should be maintained to obtain suppression of the local population. Immigration of mated females was not a main issue in the small villages where trials have been run. PMID:23540120

  2. The sterile-male-release technique in Great Lakes sea lamprey management

    USGS Publications Warehouse

    Twohey, M.B.; Heinrich, J.W.; Seelye, J.G.; Fredricks, K.T.; Bergstedt, R.A.; Kaye, C.A.; Scholefield, R.J.; McDonald, R.B.; Christie, G.C.

    2003-01-01

    The implementation of a sterile-male-release technique from 1991 through 1999 and evaluation of its effectiveness in the Great Lakes sea lamprey (Petromyzon marinus) management program is reviewed. Male sea lampreys were injected with the chemosterilant bisazir (P,P-bis(1-aziridinyl)-N- methylphosphinothioic amide) using a robotic device. Quality assurance testing indicated the device delivered a consistent and effective dose of bisazir. Viability of embryos in an untreated control group was 64% compared to 1% in a treatment group. A task force developed nine hypotheses to guide implementation and evaluation of the technique. An annual average of 26,000 male sea lampreys was harvested from as many as 17 Great Lakes tributaries for use in the technique. An annual average of 16,100 sterilized males was released into 33 tributaries of Lake Superior to achieve a theoretical 59% reduction in larval production during 1991 to 1996. The average number of sterile males released in the St. Marys River increased from 4,000 during 1991 to 1996 to 20,100 during 1997 to 1999. The theoretical reduction in reproduction when combined with trapping was 57% during 1991 to 1996 and 86% during 1997 to 1999. Evaluation studies demonstrated that sterilized males were competitive and reduced production of larvae in streams. Field studies and simulation models suggest reductions in reproduction will result in fewer recruits, but there is risk of periodic high recruitment events independent of sterile-male release. Strategies to reduce reproduction will be most reliable when low densities of reproducing females are achieved. Expansion of the technique is limited by access to additional males for sterilization. Sterile-male release and other alternative controls are important in delivering integrated pest management and in reducing reliance on pesticides.

  3. The sterile-male-release technique in Great Lakes sea lamprey management

    USGS Publications Warehouse

    Twohey, Michael B.; Heinrich, John W.; Seelye, James G.; Fredricks, Kim T.; Bergstedt, Roger A.; Kaye, Cheryl A.; Scholefield, Ron J.; McDonald, Rodney B.; Christie, Gavin C.

    2003-01-01

    The implementation of a sterile-male-release technique from 1991 through 1999 and evaluation of its effectiveness in the Great Lakes sea lamprey (Petromyzon marinus) management program is reviewed. Male sea lampreys were injected with the chemosterilant bisazir (P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide) using a robotic device. Quality assurance testing indicated the device delivered a consistent and effective dose of bisazir. Viability of embryos in an untreated control group was 64% compared to 1% in a treatment group. A task force developed nine hypotheses to guide implementation and evaluation of the technique. An annual average of 26,000 male sea lampreys was harvested from as many as 17 Great Lakes tributaries for use in the technique. An annual average of 16,100 sterilized males was released into 33 tributaries of Lake Superior to achieve a theoretical 59% reduction in larval production during 1991 to 1996. The average number of sterile males released in the St. Marys River increased from 4,000 during 1991 to 1996 to 20,100 during 1997 to 1999. The theoretical reduction in reproduction when combined with trapping was 57% during 1991 to 1996 and 86% during 1997 to 1999. Evaluation studies demonstrated that sterilized males were competitive and reduced production of larvae in streams. Field studies and simulation models suggest reductions in reproduction will result in fewer recruits, but there is risk of periodic high recruitment events independent of sterile-male release. Strategies to reduce reproduction will be most reliable when low densities of reproducing females are achieved. Expansion of the technique is limited by access to additional males for sterilization. Sterile-male release and other alternative controls are important in delivering integrated pest management and in reducing reliance on pesticides.

  4. Epidemiological characteristics of male sexual assault in a criminological database.

    PubMed

    Choudhary, Ekta; Gunzler, Douglas; Tu, Xin; Bossarte, Robert M

    2012-02-01

    Sexual assault among males, compared with females, is understudied, and may also be significantly underreported. Past studies have relied primarily on population-based survey data to estimate the prevalence of sexual assault and associated health outcomes. However, survey-based studies rely primarily on self-reports of victimization and may not accurately estimate the true prevalence of male sexual assault victimization. In order to obtain a detailed assessment of sexual assault among males, criminological databases like the National Incident Based Reporting System (NIBRS) may provide an important and unique source of information. The objective of the current study was to use data from the 2001-2005 NIBRS to construct an epidemiological profile of sexual assault among males. Our results suggest that the incidence of sexual assault was higher among young males (less than 19 years of age), with approximately 90% of all cases being reported among members of this age group. Among males of all ages, forcible fondling and sodomy were the most prevalent forms of sexual assault. Results from additional analyses include age- and race-specific rates of male sexual assault, the prevalence and severity of injury, and time trends detailing incidence by time of the day and location of the incident. Our analyses show that sexual assault is experienced by males of all age groups. However, the rate of sexual assault is higher among younger males. Despite some limitations, results from this study suggest that NIBRS data may provide a important complement to survey data for understanding breadth and consequences of male sexual assault. PMID:21987510

  5. Sexual size dimorphism and male combat in snakes

    Microsoft Academic Search

    Richard Shine

    1978-01-01

    This paper reviews published literature on snakes to test the hypothesis that large male size, relative to female size, evolves because of the advantage it confers in male combat. Analysis of the data reveals a high correlation between the occurrence of male combat, and sexual dimorphism in which the male is the larger sex. This correlation holds (i) within the

  6. Sexual selection by male-male competition in natterjack toad choruses

    Microsoft Academic Search

    Anthony Arak

    1983-01-01

    A major controversy of sexual selection theory is whether sexually dimorphic characters used in display by males have arisen through male-male competition, female choice, or both1-4. Here I describe the chorusing behaviour of male natterjack toads (Bufo calamita) and show that the pitch of the advertisement call is an important determinant of male mating success. Playback experiments using synthetic calls

  7. Molecular mapping of three male-sterile, female-fertile mutants and generation of a comprehensive map of all known male sterility genes in soybean.

    PubMed

    Yang, Yang; Speth, Benjamin D; Boonyoo, Napatsakorn; Baumert, Eric; Atkinson, Taylor R; Palmer, Reid G; Sandhu, Devinder

    2014-03-01

    In soybean, an environmentally stable male sterility system is vital for making hybrid seed production commercially viable. Eleven male-sterile, female-fertile mutants (ms1, ms2, ms3, ms4, ms5, ms6, ms7, ms8, ms9, msMOS, and msp) have been identified in soybean. Of these, eight (ms2, ms3, ms5, ms7, ms8, ms9, msMOS, and msp) have been mapped to soybean chromosomes. The objectives of this study were to (i) locate the ms1, ms4, and ms6 genes to soybean chromosomes; (ii) generate genetic linkage maps of the regions containing these genes; and (iii) develop a comprehensive map of all known male-sterile, female-fertile genes in soybean. The bulked segregant analysis technique was used to locate genes to soybean chromosomes. Microsatellite markers from the corresponding chromosomes were used on F2 populations to generate genetic linkage maps. The ms1 and ms6 genes were located on chromosome 13 (molecular linkage group F) and ms4 was present on chromosome 2 (molecular linkage group D1b). Molecular analyses revealed markers Satt516, BARCSOYSSR_02_1539, and AW186493 were located closest to ms1, ms4, and ms6, respectively. The ms1 and ms6 genes, although present on the same chromosome, were independently assorting with a genetic distance of 73.7 cM. Using information from this study and compiled information from previously published male sterility genes in soybean, a comprehensive genetic linkage map was generated. Eleven male sterility genes were present on seven soybean chromosomes. Four genes were present in two regions on chromosome 2 (molecular linkage group D1b) and two genes were present on chromosome 13 (molecular linkage group F). PMID:24814801

  8. Sexual Self-Concept and Sexually Abused Males: Early Data on the Development of a Scale

    Microsoft Academic Search

    Jozef Wawrzyniec Spychala Spiegel

    2008-01-01

    This article describes the early development and psychometric piloting of the Sexual Self-Concept Scale for Sexually Abused Males, a one-dimensional measure assessing the gender-based self-perceptions of males with histories of childhood sexual abuse (CSA). A sample of 459 males with histories of CSA completed a demographic survey and responded to a pool of items using a Likert-type scale. Strong and

  9. REGISTRATION OF SEVEN CYTOPLASMIC MALE-STERILE AND FOUR FERTILITY RESTORATION SUNFLOWER GERMPLASMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cms ANN14 originated from one male-sterile plant identified in a Native American landrace PI 432513, and is a BC5 bulk with the pedigree of cms PI 432513/6*HA 89. Restoration genes for cms PI 432513 were found in 'Armavir', 'VNIIMK', 'P21', and male-fertile plants of PI 432513. F2 segregation ratios...

  10. REGISTRATION OF TWO CYTOPLASMIC MALE-STERILE AND EIGHT FERTILITY RESTORATION SUNFLOWER GENETIC STOCKS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male-sterile plants were identified in the wild H. annuus L. accessions PI 413178 and PI 413180, and maintained by backcrossing with the inbred line HA 89. Male-fertile progenies from crosses between cms plants of the two PIs and 12 USDA inbred lines indicated the presence of fertility restoration g...

  11. Male Sexual Behavior and Pheromone Emission Is Enhanced by Exposure to Guava Fruit Volatiles in Anastrepha fraterculus

    PubMed Central

    Bachmann, Guillermo E.; Segura, Diego F.; Devescovi, Francisco; Juárez, M. Laura; Ruiz, M. Josefina; Vera, M. Teresa; Cladera, Jorge L.; Fernández, Patricia C.

    2015-01-01

    Background Plant chemicals can affect reproductive strategies of tephritid fruit flies by influencing sex pheromone communication and increasing male mating competitiveness. Objective and Methodology We explored whether exposure of Anastrepha fraterculus males to guava fruit volatiles and to a synthetic blend of volatile compounds released by this fruit affects the sexual performance of wild and laboratory flies. By means of bioassays and pheromone collection we investigated the mechanism underlying this phenomenon. Results Guava volatile exposure enhanced male mating success and positively affected male calling behavior and pheromone release in laboratory and wild males. Changes in male behavior appear to be particularly important during the initial phase of the sexual activity period, when most of the mating pairs are formed. Exposure of laboratory males to a subset of guava fruit volatiles enhanced mating success, showing that the response to the fruit might be mimicked artificially. Conclusions Volatiles of guava seem to influence male mating success through an enhancement of chemical and physical signals related to the communication between sexes. This finding has important implications for the management of this pest species through the Sterile Insect Technique. We discuss the possibility of using artificial blends to improve the sexual competitiveness of sterile males. PMID:25923584

  12. Male brush-turkeys attempt sexual coercion in unusual circumstances.

    PubMed

    Wells, David A; Jones, Darryl N; Bulger, David; Brown, Culum

    2014-07-01

    Sexual coercion by males is generally understood to have three forms: forced copulation, harassment and intimidation. We studied Australian brush-turkeys, Alectura lathami, to determine whether some male behaviours towards females at incubation mounds could be classified as aggressive, whether males were attempting sexual coercion and, if so, whether the coercion was successful. We found that some male behaviours towards females were significantly more likely to be followed by the cessation of female mound activity, and hence could be classified as aggressive, while others were significantly more likely to be followed by the commencement of female mound activity, and hence could be classified as enticing. Copulation was preceded by higher rates of male enticement and by higher rates of certain types of male aggression. It therefore seemed that males were attempting sexual coercion. There was little evidence, however, that this combination of coercion and enticement was successful in obtaining copulations. While forced copulation did occur, it was infrequent, and no evidence could be found for intimidation. We conclude that harassment is the primary form of sexual coercion by male brush-turkeys. Although sexual coercion is understood to be a sub-optimal tactic, brush-turkey sexual coercion was employed as a primary tactic by dominant males who owned incubation mounds. One possible explanation for this apparent paradox is that aggression is the default solution for social conflicts in this species, and hence can be interpreted as a behavioural syndrome. PMID:24932897

  13. MALE STERILITY (Kaul 1988) A. INFERTILITY VS. INCOMPATIBILITY

    E-print Network

    Bhattacharyya, Madan Kumar

    plants or no male flowers in dioecious plants. b. Failure to develop normal microsporogenous tissue as the failure of plants to produce functional anthers, pollen, or male gametes. a. 1st documentation: 1763

  14. No evidence for local adaptation between cytoplasmic male sterility and nuclear restorer genes in the gynodioecious species Thymus vulgaris L

    Microsoft Academic Search

    L. GIGORD; C Lavigne; J. A. SHYKOFF; A Atlan

    1998-01-01

    In Thymus vulgaris L., sex determination involves both the nuclear and the cytoplasmic genomes: the cytoplasm is responsible for male sterility (the female phenotype) whereas specific nuclear genes may restore male fertility (the hermaphrodite phenotype). The evolutionary dynamics of cytoplasmic male-sterility genes and nuclear restorer genes represents a coevolutionary conflict. Here we draw a parallel between this conflict and the

  15. Fine mapping of a gene for non-pollen type thermosensitive genic male sterility in rice ( Oryza sativa L.)

    Microsoft Academic Search

    H. F. Peng; X. H. Chen; Y. P. Lu; Y. F. Peng; B. H. Wan; N. D. Chen; B. Wu; S. P. Xin; G. Q. Zhang

    2010-01-01

    The thermo-sensitive genic male sterility (TGMS) lines play a crucial role in two-line hybrid rice production. For a practical\\u000a TGMS line, the stability of male sterility is one of the most important technical indicators. In this study, XianS, a spontaneous\\u000a mutant with stable male sterility from an indica rice cultivar Xianhuangzhan, was classified as a non-pollen type TGMS line. The

  16. Perceptions of Child Support and Sexual Activity of Adolescent Males

    ERIC Educational Resources Information Center

    Huang, Chien-Chung; Han, Wen-Jui

    2004-01-01

    Using the 1995 new cohort of the National Survey of Adolescent Males, this paper examines the association between perceptions of child support and adolescent males' sexual activity. The results indicate that adolescent males who expect the chance of being required to pay child support is high if one becomes a non-resident father or who has a…

  17. Sexual sterilization of the daggerblade grass shrimp Palaemonetes pugio (Decapoda: Palaemonidae) by the bopyrid isopod Probopyrus pandalicola (Isopoda: Bopyridae).

    PubMed

    Sherman, Michele B; Curran, Mary Carla

    2015-02-01

    Probopyrus pandalicola is a bopyrid isopod that infects several palaemonid shrimp species, including the daggerblade grass shrimp Palaemonetes pugio . The parasite can have several negative effects on its host, including loss of hemolymph, reduced reproductive potential, and decreased molting frequency and growth. To date, there are conflicting reports on whether Probopyrus pandalicola affects the reproductive capability of both male and female daggerblade grass shrimp. The purpose of this study was to determine whether infection by Probopyrus pandalicola resulted in the sexual sterilization of Palaemonetes pugio , and if the reproductive capability of male and/or female shrimp was restored after the bopyrid was removed. We found that parasitized and deparasitized males were able to fertilize the eggs of unparasitized females successfully, as 18.9 ± 7.1% and 42.7 ± 5.2% of the females paired with them became ovigerous in 4 wk, respectively. Neither parasitized nor deparasitized females became ovigerous when placed with unparasitized males during the 4-wk period. However, 45.4 ± 20.6% of deparasitized females did become ovigerous within 10 wk. Despite the fact that female shrimp are able to reproduce again when no longer parasitized, the majority of females remain infected with the bopyrid for their entire lives. Therefore, the sexual sterilization of female shrimp could potentially have a significant impact on estuarine food webs, as grass shrimp are conduits of detrital energy and a food source for many recreationally and commercially important species in estuaries on the East Coast of the United States and in the Gulf of Mexico. PMID:25353615

  18. On the difficulties of discriminating between major and minor hybrid male sterility factors in Drosophila by examining the segregation ratio of sterile and fertile sons in backcrossing experiments.

    PubMed

    Maside, X R; Naveira, H F

    1996-10-01

    The observation of segregation ratios of sterile and fertile males in offspring samples from backcrossed hybrid females is, in principle, a valid method to unveil the genetic basis of hybrid male sterility in Drosophila. When the female parent is heterozygous (hybrid) for a sterility factor with major effects, equal proportions of fertile and sterile sons are expected in her offspring. However, intact (not recombined) chromosome segments of considerable length are expected to give segregation ratios that can not be easily differentiated from the 1:1 ratio expected from a single factor. When the phenotypic character under analysis can be determined by combinations of minor factors from the donor species spanning a certain chromosome length, very large offspring samples may be needed to test this alternative hypothesis against the null hypothesis of a single major factor. This is particularly the case of hybrid male sterility determinants in Drosophila. PMID:8885383

  19. [Perinatal clomiphene citrate treatment changes sexual orientations of male mice].

    PubMed

    He, Feng-Qin; Zhang, Heng-Rui

    2013-10-01

    Perinatal period and adolescence are critical for brain development, which is the biological basis of an individual's sexual orientation and sexual behavior. In this study, animals were divided into two groups and their sexual orientations were observed: one group experienced drug treatments during the perinatal period, and the other group was castrated at puberty. The results showed that estradiol treatment had no effect on mature male offspring's sexual orientations, but 9 days and 14 days of clomiphene citrate treatment significantly increased the chance of homosexuality and effeminized behavior. In addition, the sexual orientation of mature normal male offspring, which were castrated when they were 21 days old,was not significant different from the control animals. These findings suggest that the inhibition of perinatal estrogen activities could suppress individual male-typical responses, enhance female-typical responses and induce homosexual orientations. Moreover, the masculinizing effects of estrogen were more obvious during perinatal period than adolescence. PMID:24115661

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

    ERIC Educational Resources Information Center

    Pomerantz, Sherry C.; Vergare, Michael J.

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

  1. Routine Activity Theory and Sexual Deviance Among Male College Students

    Microsoft Academic Search

    Arrick Jackson; Katherine Gilliland; Louis Veneziano

    2006-01-01

    Much research on sexual deviance on university and college campuses is limited by its narrow focus on group affiliation. In this study, it is argued that prior deviance and opportunity serve as more robust predictor variables of sexual deviance. Using a sample of 304 male college students from four universities within the Ohio Valley Conference, this paper utilizes Analytic moment

  2. Male Involvement: Implications for Reproductive and Sexual Health Programs

    ERIC Educational Resources Information Center

    Edmunds, Lena; Rink, Elizabeth; Zukoski, Ann P.

    2004-01-01

    The sexual health needs of young males have been largely ignored in the field of reproductive health. Until recently, the health care needs of females have received the vast majority of attention from public health professionals and organizations with services focused on the prevention of teen pregnancy, sexually transmitted infections, and…

  3. Sexual exclusivity versus openness in gay male couples

    Microsoft Academic Search

    David Blasband; Letitia Anne Peplau

    1985-01-01

    Forty gay male couples participated in a questionnaire study comparing relationships that partners agreed were sexually open (N =23) and relationships that partners agreed were sexually closed (N =17). No significant differences were found in the quality of open versus closed relationships. Almost all men (93%) said they were in love with their partner. On scales assessing degree of love

  4. A Social Learning Theory Comparison of the Sexual Victimization of Adolescent Sexual Offenders and Nonsexual Offending Male Delinquents.

    ERIC Educational Resources Information Center

    Burton, David L.; Miller, Diane Lynn; Shill, Chien Tai

    2002-01-01

    A study compared 216 adolescent sexually victimized sexual offenders and 93 adolescent sexually victimized nonsexual offending delinquents. Sexually offending delinquents had closer relationships with their perpetrators, a higher chance of having a male perpetrator, a longer duration of sexual victimization, more forceful sexual victimization, and…

  5. A thermogenic secondary sexual character in male sea lamprey

    USGS Publications Warehouse

    Chung-Davidson, Yu-Wen; Priess, M. Cody; Yeh, Chu-Yin; Brant, Cory O.; Johnson, Nicholas S.; Li, Ke; Nanlohy, Kaben G.; Bryan, Mara B.; Brown, C. Titus; Choi, Jongeun; Li, Weiming

    2013-01-01

    Secondary sexual characters in animals are exaggerated ornaments or weapons for intrasexual competition. Unexpectedly, we found that a male secondary sexual character in sea lamprey (Petromyzon marinus ) is a thermogenic adipose tissue that instantly increases its heat production during sexual encounters. This secondary sexual character, developed in front of the anterior dorsal fin of mature males, is a swollen dorsal ridge known as the ‘rope’ tissue. It contains nerve bundles, multivacuolar adipocytes and interstitial cells packed with small lipid droplets and mitochondria with dense and highly organized cristae. The fatty acid composition of the rope tissue is rich in unsaturated fatty acids. The cytochrome c oxidase activity is high but the ATP concentration is very low in the mitochondria of the rope tissue compared with those of the gill and muscle tissues. The rope tissue temperature immediately rose up to 0.3°C when the male encountered a conspecific. Mature males generated more heat in the rope and muscle tissues when presented with a mature female than when presented with a male (paired t-test, P-3 more heat than the muscle in 10 min. Transcriptome analyses revealed that genes involved in fat cell differentiation are upregulated whereas those involved in oxidative-phosphorylation-coupled ATP synthesis are downregulated in the rope tissue compared with the gill and muscle tissues. Sexually mature male sea lamprey possess the only known thermogenic secondary sexual character that shows differential heat generation toward individual conspecifics.

  6. Sexual maturation and aging of adult male mealybug (Hemiptera: Pseudococcidae).

    PubMed

    Mendel, Z; Protasov, A; Jasrotia, P; Silva, E B; Zada, A; Franco, J C

    2012-08-01

    The physiological age of adult males of seven mealybug species was measured in relation to the elongation of the male pair of the waxy caudal filaments. These filaments begin to emerge after eclosion and reached their maximum length from 29.4-46.6 h. The studied males were divided into three age groups, expressed as percentages of the total waxy caudal filaments length. Attraction to a sex pheromone source was significantly higher in the oldest male group (maximum filaments growth) compared with youngest one. Only the oldest male group copulated successfully; few of the younger males tested displayed 'courtship' behavior towards conspecific virgin females. The calculated duration of the sexually active phase of the adult male life cycle varied among species ranging from 34.4 to 46.6 h. There were marked variations in the strength of attraction to a pheromone source according to time of day. There was a continuous decrease in sexual activity from morning to evening. Our findings reveal clear maturation periods for adult males of the seven studied species. The long immature phase of the adult male mealybug is probably also related to several physiological processes that are needed to complete male maturation. The most noticeable change is the elongation of the waxy caudal filaments. However, mating may be performed at any time ambient conditions are suitable. Whereas male mealybug flight towards a pheromone source is restricted to a few hours, the male may continue mating activity throughout its sexually active period. PMID:22082650

  7. Male cognitive performance declines in the absence of sexual selection

    PubMed Central

    Hollis, Brian; Kawecki, Tadeusz J.

    2014-01-01

    Sexual selection is responsible for the evolution of male ornaments and armaments, but its role in the evolution of cognition—the ability to process, retain and use information—is largely unexplored. Because successful courtship is likely to involve processing information in complex, competitive sexual environments, we hypothesized that sexual selection contributes to the evolution and maintenance of cognitive abilities in males. To test this, we removed mate choice and mate competition from experimental populations of Drosophila melanogaster by enforcing monogamy for over 100 generations. Males evolved under monogamy became less proficient than polygamous control males at relatively complex cognitive tasks. When faced with one receptive and several unreceptive females, polygamous males quickly focused on receptive females, whereas monogamous males continued to direct substantial courtship effort towards unreceptive females. As a result, monogamous males were less successful in this complex setting, despite being as quick to mate as their polygamous counterparts with only one receptive female. This diminished ability to use past information was not limited to the courtship context: monogamous males (but not females) also showed reduced aversive olfactory learning ability. Our results provide direct experimental evidence that the intensity of sexual selection is an important factor in the evolution of male cognitive ability. PMID:24573848

  8. Pain Reduces Sexual Motivation in Female But Not Male Mice

    PubMed Central

    Farmer, Melissa A.; Leja, Alison; Foxen-Craft, Emily; Chan, Lindsey; MacIntyre, Leigh C.; Niaki, Tina; Chen, Mengsha; Mapplebeck, Josiane C.S.; Tabry, Vanessa; Topham, Lucas; Sukosd, Melissa; Binik, Yitzchak M.; Pfaus, James G.

    2014-01-01

    Chronic pain is often associated with sexual dysfunction, suggesting that pain can reduce libido. We find that inflammatory pain reduces sexual motivation, measured via mounting behavior and/or proximity in a paced mating paradigm, in female but not male laboratory mice. Pain was produced by injection of inflammogens zymosan A (0.5 mg/ml) or ?-carrageenan (2%) into genital or nongenital (hind paw, tail, cheek) regions. Sexual behavior was significantly reduced in female mice experiencing pain (in all combinations); male mice similarly treated displayed unimpeded sexual motivation. Pain-induced reductions in female sexual behavior were observed in the absence of sex differences in pain-related behavior, and could be rescued by the analgesic, pregabalin, and the libido-enhancing drugs, apomorphine and melanotan-II. These findings suggest that the well known context sensitivity of the human female libido can be explained by evolutionary rather than sociocultural factors, as female mice can be similarly affected. PMID:24760835

  9. Male-Sterility Induction in Transgenic Tobacco Plants with an Unedited atp6 Mitochondrial Gene from Wheat

    Microsoft Academic Search

    Michel Hernould; Sony Suharsono; Simon Litvak; Alejandro Araya; Armand Mouras

    1993-01-01

    Cytoplasmic male sterility in plants is associated with mitochondrial dysfunction. We have proposed that a nuclear-encoded chimeric peptide formed by mitochondrial sequences when imported into the mitochondria may impair organelle function and induce male sterility in plants. A model developed to test this hypothesis is reported here. Assuming that the editing process in higher plant mitochondria reflects a requirement for

  10. MOLECULAR MAPPING OF A NUCLEAR MALE-STERILITY GENE IN SUNFLOWER (HELIANTHUS ANNUUS L.) USING TRAP AND SSR MARKERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A nuclear male-sterile mutant, NMS 360, possesses a single recessive gene, ms9, controlling male sterility. The present study identified DNA markers linked to the ms9 gene in an F2 population derived from the cross of NMS 360 x RHA 271 and maps the ms9 gene to an existing sunflower SSR linkage map. ...

  11. Novel composition of mitochondrial genomes in Petunia somatic hybrids derived from cytoplasmic male sterile and fertile plants

    Microsoft Academic Search

    Maury L. Boeshore; Irit Lifshitz; Maureen R. Hanson; Shamay Izhar

    1983-01-01

    The mitochondrial genomes of petunia somatic hybrid plants, which were derived from the fusion of male fertile P. hybrida protoplasts with cytoplasmic male sterile P. parodii protoplasts, were analyzed by endonuclease restriction and Southern blot hybridization analyses. We studied sterile and fertile somatic hybrids to address two main questions. First, is there any correlation between the mitochondrial DNA restriction banding

  12. Inheritance of Fertility Restoration for Two Cytoplasmic Male Sterility Sources of Helianthus pauciflorus (rigidus) Nutt

    Microsoft Academic Search

    C. C. Jan; T. X. Zhang; J. F. Miller; G. N. Fick

    to have H. tuberosus cytoplasm. This was not generally recognized until the discovery of the vigor restoration New sources of cytoplasmic male sterility (cms) and fertility restora- genes in many cultivated lines obtained by crossing them tion genes would reduce the genetic vulnerability of commercial sun- flower (Helianthus annuus L.) hybrids because of the current use of with vigor-reduced HA89

  13. The effect of male sterility on oil content and seed yield in sunflowers (Helianthus annuus L.)

    E-print Network

    Paris-Sud XI, Université de

    The effect of male sterility on oil content and seed yield in sunflowers (Helianthus annuus L stérilité mâle sur la teneur en huile et le rendement en grains chez le tournesol (Helian- thus annuus L différences entre mâle-stérile et mâle- fertile ne soient pas dues au cytoplasme mâle-stérile de Helianthus

  14. Genetics of Male Sterility in Gynodioecious Plantago Coronopus. II. Nuclear Genetic Variation

    PubMed Central

    Koelewijn, H. P.; Van-Damme, JMM.

    1995-01-01

    Inheritance of male sterility was studied in the gynodioecious species Plantago coronopus using five plants and their descendants from an area of ~50 m(2) from each of four locations. In each location, crosses between these five plants yielded the entire array of possible sex phenotypes. Both nuclear and cytoplasmic genes were involved. Emphasis is placed on the nuclear (restorer) genetics of two cytoplasmic types. For both types, multiple interacting nuclear genes were demonstrated. These genes carried either dominant or recessive restorer alleles. The exact number of genes involved could not be determined, because different genetic models could be proposed for each location and no common genetic solution could be given. At least five genes, three with dominant and two with recessive restorer allele action, were involved with both cytoplasmic types. Segregation patterns of partially male sterile plants suggested that they are due to incomplete dominance at restorer loci. Restorer genes interact in different ways. In most instances models with independent restorer gene action were sufficient to explain the crossing results. However, for one case we propose a model with epistatic restorer gene action. There was a consistent difference in the segregation of male sterility between plants from the two cytoplasmic types. Hermaphrodites of cytoplasmic type 2 hardly segregated male steriles, in contrast to plants with cytoplasmic type 1. PMID:7789776

  15. Induction of male sterility in plants by metabolic engineering of the carbohydrate supply

    Microsoft Academic Search

    Marc Goetz; Dietmute E. Godt; Anne Guivarc'h; Uwe Kahmann; Dominique Chriqui; Thomas Roitsch

    2001-01-01

    Extracellular invertase mediates phloem unloading via an apoplastic pathway. The gene encoding isoenzyme Nin88 from tobacco was cloned and shown to be characterized by a specific spatial and temporal expression pattern. Tissue-specific antisense repression of Nin88 under control of the corresponding promoter in tobacco results in a block during early stages of pollen development, thus, causing male sterility. This result

  16. The Male Sterility Locus ms3 is Present in a Fertility Controlling Gene Cluster in Soybean

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean [Glycine max (L.) Merr.] is a self-pollinated plant. Manual cross-pollination is used to produce limited quantities of hybrid seed. To produce large quantities of hybrid seed, insect-mediated cross-pollination is necessary. An efficient nuclear male-sterile system for hybrid seed producti...

  17. Identification of fertiity restores for S male-sterile maize: beyond PPRs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nuclear genes are essential for expression of the mitochondrial genome and for the function of mitochondrial protein complexes. Interaction of the plant mitochondrial and nuclear genetic systems is exemplified by mitochondrial-encoded cytoplasmic male sterility (CMS) under the control of nuclear fe...

  18. Restoration of fertility by antisense RNA in genetically engineered male sterile tobacco plants

    Microsoft Academic Search

    Thomas Schmülling; Horst Röhrig; Silke Pilz; Richard Walden; Jeff Schell

    1993-01-01

    Transgenic tobacco plants (Nicotiana tabacum L.) expressing the rolC gene of Agrobacterium rhizogenes under the transcriptional control of the 35S RNA promoter are male sterile. When these plants are genetically crossed with others containing the rolC gene linked in antisense orientation to the 35S RNA promoter, hybrid progeny display restoration of male fertility. Moreover, hybrid progeny are revertant for other

  19. RNAi-mediated male sterility of tobacco by silencing TA29

    Microsoft Academic Search

    Muhammad Shah Nawaz-ul-Rehman; Shahid Mansoor; Asif Ali Khan; Yusuf Zafar; Rob W. Briddon

    2007-01-01

    The superior performance of F1 hybrids has a significant impact on agricultural productivity. For commercial application, the availability of an efficient\\u000a system for obtaining male-sterile lines of crops is an essential prerequisite. Here we have investigated the use of RNA interference\\u000a (RNAi) technology to silence a male-specific gene in the model host tobacco. TA29 is expressed exclusively in anthers at

  20. Expression of kenaf mitochondrial chimeric genes HM184 causes male sterility in transgenic tobacco plants.

    PubMed

    Zhao, Yanhong; Liao, Xiaofang; Huang, Zhipeng; Chen, Peng; Zhou, Bujin; Liu, Dongmei; Kong, Xiangjun; Zhou, Ruiyang

    2015-08-01

    Chimeric genes resulting from the rearrangement of a mitochondrial genome were generally thought to be a causal factor in the occurrence of cytoplasmic male sterility (CMS). In the study, earlier we reported that identifying a 47?bp deletion at 3'- flanking of atp9 that was linked to male sterile cytoplasm in kenaf. The truncated fragment was fused with atp9, a mitochondrial transit signal (MTS) and/or GFP, comprised two chimeric genes MTS-HM184-GFP and MTS-HM184. The plant expression vector pBI121 containing chimeric genes were then introduced to tobacco plants by Agrobacterium-mediated T-DNA transformation. The result showed that certain transgenic plants were male sterility or semi-sterility, while some were not. The expression analysis further demonstrated that higher level of expression were showed in the sterility plants, while no expression or less expression in fertility plants, the levels of expression of semi-sterility were in between. And the sterile plant (containing MTS-HM184-GFP) had abnormal anther produced malformed/shriveled pollen grains stained negative that failed to germinate (0%), the corresponding fruits was shrunken, the semi-sterile plants having normal anther shape produced about 10-50% normal pollen grains, the corresponding fruits were not full, and the germination rate was 58%. Meanwhile these transgenic plants which altered on fertility were further analyzed in phenotype. As a result, the metamorphosis leaves were observed in the seedling stage, the plant height of transgenic plants was shorter than wild type. The growth duration of transgenic tobacco was delayed 30-45 days compared to the wild type. The copy numbers of target genes of transgenic tobacco were analyzed using the real-time quantitative method. The results showed that these transgenic plants targeting-expression in mitochondrial containing MTS-HM184-GFP had 1 copy and 2 copies, the other two plants containing MTS-HM184 both had 3 copies, but 0 copy in wild type. In summary, the two manual chimeric genes might be related to male sterility in kenaf. PMID:24617462

  1. Psychodynamic group therapy for male survivors of sexual abuse

    Microsoft Academic Search

    Robert M. Friedman

    1994-01-01

    The group therapy literature on male sexual abuse is very preliminary and concerned solely with short-term support models. This paper describes a long-term psychodynamic therapy group for male survivors that has been running successfully in a clinic setting for almost three years. This combined group and individual treatment approach presupposes the selection of men who are capable of using group

  2. Sexually extravagant males age more rapidly Brian T. Preston,1

    E-print Network

    Rutkowska, Joanna

    that the expression of these traits can cause senescence is lacking. Long-lived houbara bustards (Chlamydotis undulata of sexual selection in explaining rates of ageing. Keywords Ageing rate, fertility, houbara bustard), and these are characteristics that are exhibited in abundance by male houbara bustards of North Africa. In the wild, male

  3. A novel male sterility-fertility restoration system in plants for hybrid seed production.

    PubMed

    Singh, Surendra Pratap; Singh, Sudhir P; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V

    2015-01-01

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility-fertility restoration system by engineering the inmost nutritive anther wall layer tapetum of female and male parents. In the female parent, high-level, and stringent expression of Arabidopsis autophagy-related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1(NT131)) with TBPm3 (HFR1(NT131)-TBPm3) to exercise regulatory control over it. In the male parent, tapetum-specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1(L105A)) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1-mediated degradation of TBPm3 pool (HFR1(NT131)-TBPm3). The system can be deployed for hybrid seed production in agricultural crops. PMID:26073981

  4. A novel male sterility-fertility restoration system in plants for hybrid seed production

    PubMed Central

    Singh, Surendra Pratap; Singh, Sudhir P.; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V.

    2015-01-01

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility–fertility restoration system by engineering the inmost nutritive anther wall layer tapetum of female and male parents. In the female parent, high–level, and stringent expression of Arabidopsis autophagy–related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1NT131) with TBPm3 (HFR1NT131-TBPm3) to exercise regulatory control over it. In the male parent, tapetum–specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1L105A) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1–mediated degradation of TBPm3 pool (HFR1NT131-TBPm3). The system can be deployed for hybrid seed production in agricultural crops. PMID:26073981

  5. Post-copulatory sexual selection and sexual conflict in the evolution of male pregnancy.

    PubMed

    Paczolt, Kimberly A; Jones, Adam G

    2010-03-18

    Male pregnancy in seahorses, pipefishes and sea dragons (family Syngnathidae) represents a striking reproductive adaptation that has shaped the evolution of behaviour and morphology in this group of fishes. In many syngnathid species, males brood their offspring in a specialized pouch, which presumably evolved to facilitate male parental care. However, an unexplored possibility is that brood pouch evolution was partly shaped by parent-offspring or sexual conflict, processes that would result in trade-offs between current and future pregnancies. Here we report a controlled breeding experiment using the sexually dimorphic Gulf pipefish, Syngnathus scovelli, to test for post-copulatory sexual selection within broods and for trade-offs between successive male pregnancies as functions of female attractiveness. Offspring survivorship within a pregnancy was affected by the size of a male's mate, the number of eggs transferred and the male's sexual responsiveness. Significantly, we also found that embryo survivorship in a current pregnancy was negatively related to survivorship in the prior pregnancy, clearly demonstrating fitness trade-offs between broods. Overall, our data indicate that post-copulatory sexual selection and sexual conflict occur in Gulf pipefishes. The conflict seems to be mediated by a strategy of cryptic choice in which males increase rates of offspring abortion in pregnancies from unattractive mothers to retain resources for future reproductive opportunities. Hence, the male brood pouch of syngnathid fishes, which nurtures offspring, also seems to have an important role as an arbiter of conflict between the sexes. PMID:20237568

  6. The evolutionary history of D. buzzatii. XXII. Chromosomal and genic sterility in male hybrids of Drosophila buzzatii and Drosophila koepferae.

    PubMed

    Naveira, H; Fontdevila, A

    1991-04-01

    The genetic basis of sterility in F1 male hybrids of Drosophila buzzatii and D. koepferae has been investigated in two steps. (1) By successive backcrossing of hybrid females to either parental species. (2) By assessment of the effects on male fertility of selected segments of polytene chromosomes from the donor species on a background entirely derived from the recipient species. The length of introgressed segments producing sterility was progressively reduced through repeated backcrosses. This procedure sometimes led to an approximate mapping of major genes of hybrid sterility (genic sterility) on the polytene chromosome map. At other times it was found that sterility was produced only when the introgressed segment exceeded a certain threshold size (chromosomal sterility). The contribution of the autosomes to hybrid sterility seems to be mainly of the chromosomal type. The evidence concerning the X chromosome is equivocal. No fertile males were found following introgression with any of the investigated segments of this chromosome. These results are compatible both with the presence of at least six major genes of hybrid sterility (genic sterility) and with the existence of a rather small threshold size for the chromosome segments producing sterility (chromosomal sterility). The role of the Y chromosome was not investigated in this study. PMID:2061093

  7. Genetic Architecture of Autosome-Mediated Hybrid Male Sterility in Drosophila

    PubMed Central

    Marin, I.

    1996-01-01

    Several estimators have been developed for assesing the number of sterility factors in a chromosome based on the sizes of fertile and sterile introgressed fragments. Assuming that two factors are required for producing sterility, simulations show that one of these, twice the inverse of the relative size of the largest fertile fragment, provides good average approximations when as few as five fertile fragments are analyzed. The estimators have been used for deducing the number of factors from previous data on several pairs of species. A particular result contrasts with the authors' interpretations: instead of the high number of sterility factors suggested, only a few per autosome are estimated in both reciprocal crosses involving Drosophila buzzatii and D. koepferae. It has been possible to map these factors, between three and six per chromosome, in the autosomes 3 and 4 of these species. Out of 203 introgressions of different fragments or combinations of fragments, the outcome of at least 192 is explained by the mapped zones. These results suggest that autosome-mediated sterility in the male hybrids of these species is mediated by a few epistatic factors, similarly to X-mediated sterility in the hybrids of other Drosophila species. PMID:8846896

  8. Genetic architecture of autosome-mediated hybrid male sterility in Drosophila

    SciTech Connect

    Marin, I. [Stanford Univ., CA (United States)

    1996-04-01

    Several estimators have been developed for assesing the number of sterility factors in a chromosome based on the sizes of fertile and sterile introgressed fragments. Assuming that two factors are required for producing sterility, simulations show that one of these, twice the inverse of the relative size of the largest fertile fragment, provides good average approximations when as few as five fertile fragments are analyzed. The estimators have been used for deducing the number of factors from previous data on several pairs of species. A particular result contrasts with the authors` interpretations: instead of the high number of sterility factors suggested, only a few per autosome are estimated in both reciprocal crosses involving Drosophila buzzatii and D. koepferae. It has been possible to map these factors, between three and six per chromosome, in the autosomes 3 and 4 of these species. Out of 203 introgressions of different fragments or combinations of fragments, the outcome of at least 192 is explained by the mapped zones. These results suggest that autosome-mediated sterility in the male hybrids of these species is mediated by a few epistatic factors, similarly to X-mediated sterility in the hybrids of other Drosophila species. 48 refs., 5 tabs.

  9. The male sexual partners of adult versus teen women with sexually transmitted infections

    PubMed Central

    THURMAN, Andrea Ries; HOLDEN, Alan E C; SHAIN, Rochelle N; PERDUE, Sondra T.

    2009-01-01

    Objectives We compared the male sexual partners of teen girls, age 15 - 19 years-old, currently infected with a sexually transmitted infection (STI) versus the male partners of adult women, age 20 - 41 years-old, with an STI to determine risk factors in these high-risk sexual dyads related to the male partner. Study Design Interview of 514 men who were partnered with 152 teen girls and 362 adult women, enrolled in Project Sexual Awareness for Everyone (SAFE), a randomized controlled trial of behavioral intervention to reduce recurrent STIs. Results Compared to the male partners of adult women, male partners of teen girls were significantly more likely (p < 0.05) to be infected with any STI at intake. Men partnered with teens were younger and had significantly more sexual partners per year sexually active, shorter relationship length, and shorter length of monogamy with the index girls. They were more likely to report that it was “really important” for the teen to have their baby (p = 0.04) and were slightly more likely to be the father of her children (p = 0.17). Young age independently predicted STI infection in men. Conclusions Although all women had an STI at intake, important differences were noted among the male partners of teens versus adults. Clinicians with similar populations may use this data to understand the characteristics of male partners of teens with STIs, in order to more effectively counsel adult and teen women on partner notification, treatment and STI prevention. PMID:19704393

  10. A barley PHD finger transcription factor that confers male sterility by affecting tapetal development.

    PubMed

    Fernández Gómez, José; Wilson, Zoe A

    2014-08-01

    Controlling pollen development is of major commercial importance in generating hybrid crops and selective breeding, but characterized genes for male sterility in crops are rare, with no current examples in barley. However, translation of knowledge from model species is now providing opportunities to understand and manipulate such processes in economically important crops. We have used information from regulatory networks in Arabidopsis to identify and functionally characterize a barley PHD transcription factor MALE STERTILITY1 (MS1), which expresses in the anther tapetum and plays a critical role during pollen development. Comparative analysis of Arabidopsis, rice and Brachypodium genomes was used to identify conserved regions in MS1 for primer design to amplify the barley MS1 gene; RACE-PCR was subsequently used to generate the full-length sequence. This gene shows anther-specific tapetal expression, between late tetrad stage and early microspore release. HvMS1 silencing and overexpression in barley resulted in male sterility. Additionally, HvMS1 cDNA, controlled by the native Arabidopsis MS1 promoter, successfully complemented the homozygous ms1 Arabidopsis mutant. These results confirm the conservation of MS1 function in higher plants and in particular in temperate cereals. This has provided the first example of a characterized male sterility gene in barley, which presents a valuable tool for the future control of male fertility in barley for hybrid development. PMID:24684666

  11. Adolescent Females Who Have Sexually Offended: Comparisons with Delinquent Adolescent Female Offenders and Adolescent Males Who Sexually Offend.

    ERIC Educational Resources Information Center

    Kubik, Elizabeth K.; Hecker, Jeffrey E.; Righthand, Sue

    2002-01-01

    Two-part study compared sexually-offending females with a sample of non-sexually-offending females and a sample of sexually-offending males. Sexually-offending sample had significantly fewer antisocial behavior problems (drug use, fighting, problems at school) than the non-sexually-offending female group. The two sex-offending groups were…

  12. [Questionnaires on male sexual dysfunction and their clinical application].

    PubMed

    Cai, Yang; Wang, Tao; Liu, Ji-Hong

    2014-09-01

    With the increasing incidence and prevalence of male sexual dysfunction, andrologists are more and more in need of accurate and efficient tools to assess therapeutic efficacy and patients' satisfaction and to help patients achieve satisfactory treatment results. This article summarizes some of the most commonly used questionnaires for the diagnosis and assessment of the treatment of male sexual dysfunction, including International Index of Erectile Function (IIEF), Erection Hardness Score (EHS), Quality of Erection Questionnaire (QEQ), Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS), Treatment Satisfaction Scale (TSS), Self-Esteem and Relationship (SEAR), Premature Ejaculation Profile (PEP), Premature Ejaculation Diagnostic Tool (PEDT), Index of Premature Ejaculation (IPE), Arabic Index of Premature Ejaculation (AIPE), Aging Male Symptoms Scale (AMS), Androgen Deficiency in the Aging Male (ADAM), and Symptomatic Inventory for Screening Late-Onset Hypogonadism in Males (SILOH), and presents an overview on their clinical application. PMID:25306815

  13. Sexual attractiveness of male chemicals and vocalizations in mice

    PubMed Central

    Asaba, Akari; Hattori, Tatsuya; Mogi, Kazutaka; Kikusui, Takefumi

    2014-01-01

    Male-female interaction is important for finding a suitable mating partner and for ensuring reproductive success. Male sexual signals such as pheromones transmit information and social and sexual status to females, and exert powerful effects on the mate preference and reproductive biology of females. Likewise, male vocalizations are attractive to females and enhance reproductive function in many animals. Interestingly, females' preference for male pheromones and vocalizations is associated with their genetic background, to avoid inbreeding. Moreover, based on acoustic cues, olfactory signals have significant effects on mate choice in mice, suggesting mate choice involves multisensory integration. In this review, we synopsize the effects of both olfactory and auditory cues on female behavior and neuroendocrine functions. We also discuss how these male signals are integrated and processed in the brain to regulate behavior and reproductive function. PMID:25140125

  14. Evolutionary response to sexual selection in male genital morphology.

    PubMed

    Simmons, Leigh W; House, Clarissa M; Hunt, John; García-González, Francisco

    2009-09-15

    Male genital morphology is characterized by two striking and general patterns of morphological variation: rapid evolutionary divergence in shape and complexity, and relatively low scaling relationships with body size. These patterns of variation have been ascribed to the action of sexual selection. Among species, monogamous taxa tend to have relatively less complex male genital morphology than do polygamous taxa. However, although variation in male genital morphology can be associated with variation in mating and fertilization success, there is no direct evidence that sexual selection generates the evolutionary changes in male genital shape that underlie observed macroevolutionary patterns. Moreover, the hypothesis that sexual selection acts to reduce the scaling relationship between body and genital size is based entirely on the theoretical argument that male genitalia should be selected to provide an appropriate mechanical and/or stimulatory fit to the most commonly encountered female genitalia. Here, using the dung beetle Onthophagus taurus, we combine the power of experimental evolution with multivariate selection and quantitative genetic analyses to provide the most comprehensive evidence available of the form and evolutionary consequences of sexual selection acting on male genital morphology. PMID:19664925

  15. Sexual Attractiveness of Males and Females.

    ERIC Educational Resources Information Center

    Taylor, Peggy; And Others

    The most important characteristics for females judging the attractiveness of males, and for males judging females, were eyes, body build and facial complexion. Previously, females tended to place less importance on physical components of attraction for both themselves and men. Possible interpretations are: (1) women have become more egalitarian…

  16. Alloplasmic male-sterile Brassica lines containing B. tournefortii mitochondria express an ORF 3? of the atp6 gene and a 32 kDa protein

    Microsoft Academic Search

    Maria Landgren; Mattias Zetterstrand; Eva Sundberg; Kristina Glimelius

    1996-01-01

    Analyses of mitochondrial transcription and in organello translation were performed with the Brassica tournefortii cytoplasm. This cytoplasm causes alloplasmic male sterility when combined with the nuclear genomes of B. napus and B. juncea. Mitochondrial RNA and protein banding patterns were compared between the fertile wild species B. tournefortii, an alloplasmic male-sterile B. juncea line, an alloplasmic male-sterile B. napus line

  17. A thermogenic secondary sexual character in male sea lamprey

    PubMed Central

    Chung-Davidson, Yu-Wen; Priess, M. Cody; Yeh, Chu-Yin; Brant, Cory O.; Johnson, Nicholas S.; Li, Ke; Nanlohy, Kaben G.; Bryan, Mara B.; Brown, C. Titus; Choi, Jongeun; Li, Weiming

    2013-01-01

    SUMMARY Secondary sexual characters in animals are exaggerated ornaments or weapons for intrasexual competition. Unexpectedly, we found that a male secondary sexual character in sea lamprey (Petromyzon marinus) is a thermogenic adipose tissue that instantly increases its heat production during sexual encounters. This secondary sexual character, developed in front of the anterior dorsal fin of mature males, is a swollen dorsal ridge known as the ‘rope’ tissue. It contains nerve bundles, multivacuolar adipocytes and interstitial cells packed with small lipid droplets and mitochondria with dense and highly organized cristae. The fatty acid composition of the rope tissue is rich in unsaturated fatty acids. The cytochrome c oxidase activity is high but the ATP concentration is very low in the mitochondria of the rope tissue compared with those of the gill and muscle tissues. The rope tissue temperature immediately rose up to 0.3°C when the male encountered a conspecific. Mature males generated more heat in the rope and muscle tissues when presented with a mature female than when presented with a male (paired t-test, P<0.05). On average, the rope generated 0.027±0.013 W cm?3 more heat than the muscle in 10 min. Transcriptome analyses revealed that genes involved in fat cell differentiation are upregulated whereas those involved in oxidative-phosphorylation-coupled ATP synthesis are downregulated in the rope tissue compared with the gill and muscle tissues. Sexually mature male sea lamprey possess the only known thermogenic secondary sexual character that shows differential heat generation toward individual conspecifics. PMID:23804672

  18. Gonad morphogenesis defects drive hybrid male sterility in asymmetric hybrid breakdown of Caenorhabditis nematodes.

    PubMed

    Dey, Alivia; Jin, Qi; Chen, Yen-Chu; Cutter, Asher D

    2014-01-01

    Determining the causes and evolution of reproductive barriers to gene flow between populations, speciation, is the key to understanding the origin of diversity in nature. Many species manifest hybrid breakdown when they intercross, characterized by increasingly exacerbated problems in later generations of hybrids. Recently, Caenorhabditis nematodes have emerged as a genetic model for studying speciation, and here we investigate the nature and causes of hybrid breakdown between Caenorhabditis remanei and C. latens. We quantify partial F1 hybrid inviability and extensive F2 hybrid inviability; the ~75% F2 embryonic arrest occurs primarily during gastrulation or embryonic elongation. Moreover, F1 hybrid males exhibit Haldane's rule asymmetrically for both sterility and inviability, being strongest when C. remanei serves as maternal parent. We show that the mechanism by which sterile hybrid males are incapable of transferring sperm or a copulatory plug involves defective gonad morphogenesis, which we hypothesize results from linker cell defects in migration and/or cell death during development. This first documented case of partial hybrid male sterility in Caenorhabditis follows expectations of Darwin's corollary to Haldane's rule for asymmetric male fitness, providing a powerful foundation for molecular dissection of intrinsic reproductive barriers and divergence of genetic pathways controlling organ morphogenesis. PMID:25196892

  19. An axonemal dynein at the Hybrid Sterility 6 locus: implications for t haplotype-specific male sterility and the evolution of species barriers

    Microsoft Academic Search

    John Fossella; Sadhana A. Samant; Lee M. Silver; Stephen M. King; Kevin T. Vaughan; Patricia Olds-Clarke; Karl A. Johnson; Atsushi Mikami; Richard B. Vallee; Stephen H. Pilder

    2000-01-01

    .   Poor sperm motility characterized by a distinct aberration in flagellar waveform known as ``curlicue'' is a hallmark of t haplotype (t) homozygous male sterility. Previous studies have localized ``curlicue'' and a flagellar developmental defect, ``whipless'',\\u000a to the Hybrid Sterility 6 locus (Hst6), between the markers Pim1 and Crya1. More recent heterospecific breeding experiments between Mus spretus (Spretus) and Mus

  20. Sexual Experience Enhances Drosophila melanogaster Male Mating Behavior and Success

    PubMed Central

    Saleem, Sehresh; Ruggles, Patrick H.; Abbott, Wiley K.; Carney, Ginger E.

    2014-01-01

    Competition for mates is a wide-spread phenomenon affecting individual reproductive success. The ability of animals to adjust their behaviors in response to changing social environment is important and well documented. Drosophila melanogaster males compete with one another for matings with females and modify their reproductive behaviors based on prior social interactions. However, it remains to be determined how male social experience that culminates in mating with a female impacts subsequent male reproductive behaviors and mating success. Here we show that sexual experience enhances future mating success. Previously mated D. melanogaster males adjust their courtship behaviors and out-compete sexually inexperienced males for copulations. Interestingly, courtship experience alone is not sufficient in providing this competitive advantage, indicating that copulation plays a role in reinforcing this social learning. We also show that females use their sense of hearing to preferentially mate with experienced males when given a choice. Our results demonstrate the ability of previously mated males to learn from their positive sexual experiences and adjust their behaviors to gain a mating advantage. These experienced-based changes in behavior reveal strategies that animals likely use to increase their fecundity in natural competitive environments. PMID:24805129

  1. Transient Population Dynamics of Mosquitoes during Sterile Male Releases: Modelling Mating Behaviour and Perturbations of Life History Parameters

    PubMed Central

    Stone, Christopher M.

    2013-01-01

    The release of genetically-modified or sterile male mosquitoes offers a promising form of mosquito-transmitted pathogen control, but the insights derived from our understanding of male mosquito behaviour have not fully been incorporated into the design of such genetic control or sterile-male release methods. The importance of aspects of male life history and mating behaviour for sterile-male release programmes were investigated by projecting a stage-structured matrix model over time. An elasticity analysis of transient dynamics during sterile-male releases was performed to provide insight on which vector control methods are likely to be most synergistic. The results suggest that high mating competitiveness and mortality costs of released males are required before the sterile-release method becomes ineffective. Additionally, if released males suffer a mortality cost, older males should be released due to their increased mating capacity. If released males are of a homogenous size and size-assortative mating occurs in nature, this can lead to an increase in the abundance of large females and reduce the efficacy of the population-suppression effort. At a high level of size-assortative mating, the disease transmission potential of the vector population increases due to male releases, arguing for the release of a heterogeneously-sized male population. The female population was most sensitive to perturbations of density-dependent components of larval mortality and female survivorship and fecundity. These findings suggest source reduction might be a particularly effective complement to mosquito control based on the sterile insect technique (SIT). In order for SIT to realize its potential as a key component of an integrated vector-management strategy to control mosquito-transmitted pathogens, programme design of sterile-male release programmes must account for the ecology, behaviour and life history of mosquitoes. The model used here takes a step in this direction and can easily be modified to investigate additional aspects of mosquito behaviour or species-specific ecology. PMID:24086715

  2. The makings of maleness: towards an integrated view of male sexual development

    Microsoft Academic Search

    Dagmar Wilhelm; Peter Koopman

    2006-01-01

    As the mammalian embryo develops, it must engage one of the two distinct programmes of gene activity, morphogenesis and organogenesis that characterize males and females. In males, sexual development hinges on testis determination and differentiation, but also involves many coordinated transcriptional, signalling and endocrine networks that underpin the masculinization of other organs and tissues, including the brain. Here we bring

  3. Low-oxygen atmospheric treatment improves the performance of irradiation-sterilized male cactus moths used in SIT.

    PubMed

    López-Martínez, Giancarlo; Carpenter, James E; Hight, Stephen D; Hahn, Daniel A

    2014-02-01

    As part of sterile insect technique (SIT) programs, irradiation can effectively induce sterility in insects by damaging genomic DNA. However, irradiation also induces other off-target side effects that reduce the quality and performance of sterilized males. Thus, treatments that reduce off-target effects of irradiation on male performance while maintaining sterility can improve the feasibility and economy of SIT programs. Exposure to ionizing radiation induces the formation of damaging free radicals in biological systems that may reduce sterile male performance. Here, we test whether exposure to an anoxic environment for 1 h before and during irradiation improves male performance, while maintaining sterility in males of the cactus moth, Cactoblastis cactorum (Berg). We show that exposure to 1 h of anoxia increases the moth's antioxidant capacity and that irradiation in anoxia after 1 h of anoxic conditioning decreases irradiation-induced oxidative damage to the moth's lipids and proteins. Anoxia treatment that reduced oxidative damage after irradiation also produced moths with greater flight performance, mating success, and longevity, while maintaining F1 male sterility at acceptable levels for SIT. We conclude that anoxia pretreatment followed by irradiation in anoxia is an efficient way to improve the quality of irradiated moths and perhaps lower the number of moths needed for release SIT moth operations. PMID:24665701

  4. Molecular analysis of cytoplasmic male sterility in chives ( Allium schoenoprasum L.)

    Microsoft Academic Search

    H. Potz; T. Tatlioglu

    1993-01-01

    The mitochondria of chive plants with normal N or male-sterile S cytoplasms have been examined by restriction fragment analysis and Southern hybridizations of mitochondrial DNA (mtDNA) and in organello protein biosynthesis. Restriction fragment patterns of the mtDNA differed extensively between N-and S-cytoplasms. The percentage of fragments with different mobility varied between 44–48% depending on the restriction enzyme used. In contrast

  5. Sterility and Gene Expression in Hybrid Males of Xenopus laevis and X. muelleri

    PubMed Central

    Malone, John H.; Chrzanowski, Thomas H.; Michalak, Pawel

    2007-01-01

    Background Reproductive isolation is a defining characteristic of populations that represent unique biological species, yet we know very little about the gene expression basis for reproductive isolation. The advent of powerful molecular biology tools provides the ability to identify genes involved in reproductive isolation and focuses attention on the molecular mechanisms that separate biological species. Herein we quantify the sterility pattern of hybrid males in African Clawed Frogs (Xenopus) and apply microarray analysis of the expression pattern found in testes to identify genes that are misexpressed in hybrid males relative to their two parental species (Xenopus laevis and X. muelleri). Methodology/Principal Findings Phenotypic characteristics of spermatogenesis in sterile male hybrids (X. laevis x X. muelleri) were examined using a novel sperm assay that allowed quantification of live, dead, and undifferentiated sperm cells, the number of motile vs. immotile sperm, and sperm morphology. Hybrids exhibited a dramatically lower abundance of mature sperm relative to the parental species. Hybrid spermatozoa were larger in size and accompanied by numerous undifferentiated sperm cells. Microarray analysis of gene expression in testes was combined with a correction for sequence divergence derived from genomic hybridizations to identify candidate genes involved in the sterility phenotype. Analysis of the transcriptome revealed a striking asymmetric pattern of misexpression. There were only about 140 genes misexpressed in hybrids compared to X. laevis but nearly 4,000 genes misexpressed in hybrids compared to X. muelleri. Conclusions/Significance Our results provide an important correlation between phenotypic characteristics of sperm and gene expression in sterile hybrid males. The broad pattern of gene misexpression suggests intriguing mechanisms creating the dominance pattern of the X. laevis genome in hybrids. These findings significantly contribute to growing evidence for allelic dominance in hybrids and have implications for the mechanism of species differentiation at the transcriptome level. PMID:17712429

  6. Large 3? UTR of sugar beet rps3 is truncated in cytoplasmic male-sterile mitochondria

    Microsoft Academic Search

    Muneyuki Matsunaga; Hironori Nagano; Tetsuo Mikami; Tomohiko Kubo

    2011-01-01

    Genomic alteration near or within mitochondrial gene is often associated with cytoplasmic male sterility (CMS). Its influence\\u000a on the expression of the mitochondrial gene was proposed as one of the possible causes of CMS. In sugar beet mitochondrial\\u000a rps3, whose downstream 1,056-bp region contains Norf246, an apparently non-functional open reading frame (ORF), was deleted in CMS mitochondria. In our previous

  7. Mitochondrial genome organization of the maize cytoplasmic male sterile type T

    Microsoft Academic Search

    Christiane Fauron; Marie Havlik; David Lonsdale; Lindy Nichols

    1989-01-01

    A complete SmaI, XhoI, BamHI restriction map of the maize mitochondrial genome from the T male sterile cytoplasm (cmsT) of maize has been established. The genome exists in the form of a complex multicircular structure as found for the maize normal (N) type (Lonsdale et al. 1984) where the entire sequence complexity with a content of 540 kb can be

  8. Phylogenetic relationships among fertile and petaloid male-sterile accessions of carrot, Daucus carota L

    Microsoft Academic Search

    C. E. Bowes; D. J. Wolyn

    1998-01-01

    Mitochondrial (mt) DNA variation for six petaloid cytoplasmic male-sterile (CMS) and three fertile maintainer lines of carrot\\u000a was assessed to establish genetic relationships. Total DNA was digested with restriction enzymes and probed with six homologous\\u000a mtDNA cosmid probes. The six CMS accessions derived from wild carrot, four from Guelph, Ontario, one from Orleans, Massachusetts,\\u000a and one from Madison, Wisconsin, were

  9. Chimeric mitochondrial genes expressed in the C male-sterile cytoplasm of maize

    Microsoft Academic Search

    R. E. Dewey; D. H. Timothy; C. S. Levings

    1991-01-01

    Aberrant recombinations involving the mitochondrial atp9, atp6 and coxII genes have created unique chimeric sequences in the C male0sterile cytoplasm (cms-C) of maize. An apparent consequence of the rearrangements is the interchanging of transcriptional and\\/or translational regulatory signals for these genes, and alterations in the reading frames encoding the atp6 and coxII genes in the C cytoplasm. Particularly unusual is

  10. A unique sequence located downstream from the rice mitochondrial atp6 may cause male sterility

    Microsoft Academic Search

    Hiromori Akagi; Masahiro Sakamoto; Chou Shinjyo; Hiroaki Shimada; Tatsuhito Fujimura

    1994-01-01

    Asymmetric cell-fusion of the japonica cultivar ofOryza sativa (rice) with cytoplasmic-male-sterile (CMS) plants bearing cytoplasm derived from Chinsurah Boro II, resulted in two classes of cytoplasmic hybrids (cybrids), fertile and CMS. Southern-blot analysis of the mitochondrial DNA (mtDNA) indicates recombination events around a number of genes; however, the appearance of the CMS character is tightly correlated to reorganization around theatp6

  11. Identification of mitochondrial genome rearrangements unique to novel cytoplasmic male sterility in radish ( Raphanus sativus L.)

    Microsoft Academic Search

    Young-Pyo Lee; Sunggil Kim; Heerae Lim; YoungSoon Ahn; Soon-Kee Sung

    2009-01-01

    A novel cytoplasmic male-sterility (CMS) radish (Raphanus sativus L.) and its associated mitotype (DCGMS) were previously identified; however, no mtDNA fragments flanking the atp6 gene were found in the DCGMS mitotype. Unlike three other mitotypes in this study, a unique mtDNA organization, atp6–nad3–rps12, was found to be the major mtDNA structure associated with this mitotype. This organization may have arisen

  12. Cell Type-Specific Loss of atp6 RNA Editing in Cytoplasmic Male Sterile Sorghum bicolor

    Microsoft Academic Search

    Werner Howad; Frank Kempken

    1997-01-01

    RNA editing and cytoplasmic male sterility are two important phenomena in higher plant mitochondria. To determine whether correlations might exist between the two, RNA editing in different tissues of Sorghum bicolor was compared employing reverse transcription-PCR and subsequent sequence analysis. In etiolated shoots, RNA editing of transcripts of plant mitochondrial atp6, atp9, nad3, nad4, and rps12 genes was identical among

  13. Chloroplast DNA variation in isonuclear male-sterile lines of Nicotiana

    Microsoft Academic Search

    Rafael Frankel; William R. Scowcroft; Paul R. Whitfeld

    1979-01-01

    Chloroplast DNAs of six isonuclear malesterile tobacco lines and their respective parental species were analysed with the restriction endonuclease, EcoR1. Four of the lines had the same fragmentation pattern as their respective maternal species. Two lines had a pattern which was different to either parental species. The results show that nucleotide changes can occur in chloroplast DNA of isonuclear male-sterile

  14. Species of small DNA molecules found in mitochondria from sugarbeet with normal and male sterile cytoplasms

    Microsoft Academic Search

    Andrew Powling

    1981-01-01

    Mitochondrial DNA and RNA were isolated from a range of normal and cytoplasmically male sterile sugarbeet varieties and breeding lines. When these nucleic acids were analysed by electrophoresis on agarose gels it was found that mitochondria from normal sugarbeet contain DNA species of sizes 1.3 kilobase pairs (kbp), 1.4 kbp and one of two other species of sizes 1.45 kbp

  15. Characteristic Male Urine Microbiomes Associate with Asymptomatic Sexually Transmitted Infection

    Microsoft Academic Search

    David E. Nelson; Barbara van der Pol; Qunfeng Dong; Kashi V. Revanna; Baochang Fan; Shraddha Easwaran; Erica Sodergren; George M. Weinstock; Lixia Diao; J. Dennis Fortenberry; Raphael H. Valdivia

    2010-01-01

    BackgroundThe microbiome of the male urogenital tract is poorly described but it has been suggested that bacterial colonization of the male urethra might impact risk of sexually transmitted infection (STI). Previous cultivation-dependent studies showed that a variety of non-pathogenic bacteria colonize the urethra but did not thoroughly characterize these microbiomes or establish links between the compositions of urethral microbiomes and

  16. Sexual HIV risk among gay and bisexual male methamphetamine abusers

    Microsoft Academic Search

    Dominick Frosch; Steven Shoptaw; Alice Huber; Richard A. Rawson; Walter Ling

    1996-01-01

    The current report examined HIV-related high risk sexual behaviors among a small sample of gay and bisexual male methamphetamine abusers in Los Angeles. Participants were 16 methamphetamine-abusing or -dependent gay or bisexual males who participated in a treatment demonstration project between 1989 and 1993. All participants completed the NIDA\\/WAVE survey, a detailed inventory of HIV-related risk behaviors. Findings indicate a

  17. Down regulation of Hsp70 expression level prolongs the duration of heat-induced male sterility in Drosophila buzzatii

    Microsoft Academic Search

    P. SARUP; J. DAHLGAARD; A.-M. NORUP; K. T. JORGENSEN; M. B. HEBSGAARD; V. LOESCHCKE

    2004-01-01

    Summary 1. The relationship between heat shock protein Hsp70 expression level and the duration of heat-induced male sterility was investigated in four populations of Drosophila buzzatii Patterson and Wheeler. The effect of heat hardening on the duration of sterility was fur- ther examined after flies developed at either 25 or 31 ? C. In addition, Hsp70 expression was measured in

  18. Using Bulked Extremes and Recessive Class to Map Genes for Photoperiod-Sensitive Genic Male Sterility in Rice

    Microsoft Academic Search

    Qifa Zhang; B. Z. Shen; X. K. Dai; M. H. Mei; M. A. Saghai Maroof; Z. B. Li

    1994-01-01

    Photoperiod-sensitive genic male sterile (PSGMS) rice has a number of desirable characteristics for hybrid rice production. In this study we made use of a published rice genetic linkage map to determine the locations of PSGMS genes and we have characterized the effects of these genes on sterility by using molecular markers. A two-step approach was designed for mapping the genes:

  19. Sex ratio meiotic drive as a plausible evolutionary mechanism for hybrid male sterility.

    PubMed

    Zhang, Linbin; Sun, Tianai; Woldesellassie, Fitsum; Xiao, Hailian; Tao, Yun

    2015-03-01

    Biological diversity on Earth depends on the multiplication of species or speciation, which is the evolution of reproductive isolation such as hybrid sterility between two new species. An unsolved puzzle is the exact mechanism(s) that causes two genomes to diverge from their common ancestor so that some divergent genes no longer function properly in the hybrids. Here we report genetic analyses of divergent genes controlling male fertility and sex ratio in two very young fruitfly species, Drosophila albomicans and D. nasuta. A majority of the genetic divergence for both traits is mapped to the same regions by quantitative trait loci mappings. With introgressions, six major loci are found to contribute to both traits. This genetic colocalization implicates that genes for hybrid male sterility have evolved primarily for controlling sex ratio. We propose that genetic conflicts over sex ratio may operate as a perpetual dynamo for genome divergence. This particular evolutionary mechanism may largely contribute to the rapid evolution of hybrid male sterility and the disproportionate enrichment of its underlying genes on the X chromosome--two patterns widely observed across animals. PMID:25822261

  20. Sex Ratio Meiotic Drive as a Plausible Evolutionary Mechanism for Hybrid Male Sterility

    PubMed Central

    Zhang, Linbin; Xiao, Hailian; Tao, Yun

    2015-01-01

    Biological diversity on Earth depends on the multiplication of species or speciation, which is the evolution of reproductive isolation such as hybrid sterility between two new species. An unsolved puzzle is the exact mechanism(s) that causes two genomes to diverge from their common ancestor so that some divergent genes no longer function properly in the hybrids. Here we report genetic analyses of divergent genes controlling male fertility and sex ratio in two very young fruitfly species, Drosophila albomicans and D. nasuta. A majority of the genetic divergence for both traits is mapped to the same regions by quantitative trait loci mappings. With introgressions, six major loci are found to contribute to both traits. This genetic colocalization implicates that genes for hybrid male sterility have evolved primarily for controlling sex ratio. We propose that genetic conflicts over sex ratio may operate as a perpetual dynamo for genome divergence. This particular evolutionary mechanism may largely contribute to the rapid evolution of hybrid male sterility and the disproportionate enrichment of its underlying genes on the X chromosome – two patterns widely observed across animals. PMID:25822261

  1. Molecular aspects of cytoplasmic male sterility in perennial ryegrass ( Lolium perenne L.): mtDNA and RNA differences between plants with male-sterile and fertile cytoplasm and restriction mapping of their atp6 and coxI homologous regions

    Microsoft Academic Search

    G. J. A. Rouwendal; J. Creemers-Molenaar; F. A. Krens

    1992-01-01

    Lolium perenne L. male-sterile and fertile cytoplasms contain different mitochondrial genomes, as revealed by Southern hybridization with a number of heterologous mitochondrial probes. In addition, transcriptional patterns of atp6 and coxI genes distinguish both cytoplasmic types. The majority of the L. perenne sequences from male-sterile and fertile cytoplasm showing homology with these two genes has been cloned and mapped by

  2. Pelvic floor and sexual male dysfunction.

    PubMed

    Pischedda, Antonella; Fusco, Ferdinando; Curreli, Andrea; Grimaldi, Giovanni; Pirozzi Farina, Furio

    2013-03-01

    The pelvic floor is a complex multifunctional structure that corresponds to the genito-urinary-anal area and consists of muscle and connective tissue. It supports the urinary, fecal, sexual and reproductive functions and pelvic statics. The symptoms caused by pelvic floor dysfunction often affect the quality of life of those who are afflicted, worsening significantly more aspects of daily life. In fact, in addition to providing support to the pelvic organs, the deep floor muscles support urinary continence and intestinal emptying whereas the superficial floor muscles are involved in the mechanism of erection and ejaculation. So, conditions of muscle hypotonia or hypertonicity may affect the efficiency of the pelvic floor, altering both the functionality of the deep and superficial floor muscles. In this evolution of knowledge it is possible imagine how the rehabilitation techniques of pelvic floor muscles, if altered and able to support a voiding or evacuative or sexual dysfunction, may have a role in improving the health and the quality of life. PMID:23695397

  3. Young Male Prostitutes: Their Knowledge of Selected Sexually Transmitted Diseases.

    ERIC Educational Resources Information Center

    Calhoun, Thomas; Pickerill, Brian

    1988-01-01

    Conducted unstructured interviews with 18 male street prostitutes between the ages of 13 and 22 to determine the extent of accurate knowledge they possessed concerning four common sexually transmitted diseases. Found that subjects possessed more factual information on gonorrhea and syphilis than on herpes and Acquired Immune Deficiency Syndrome.…

  4. Symmetry, sexual dimorphism in facial proportions and male facial attractiveness

    E-print Network

    Little, Tony

    Symmetry, sexual dimorphism in facial proportions and male facial attractiveness I. S. Penton, University of St Andrews, St Andrews, Fife KY16 9JU, UK Facial symmetry has been proposed as a marker relationships between facial symmetry and attractiveness. It was recently proposed that symmetry

  5. Breakfast of champions or kiss of death? Survival and sexual performance of protein-fed, sterile Mediterranean fruit flies (Diptera: Tephritidae)

    SciTech Connect

    Yuval, B.; Maor, M.; Levy, K. [Dept. of Entomology, Hebrew University, PO 12, Rehovot, 76100 (Israel); Kaspi, R. [Dept. of Entomology, University of California, Davis CA 95616 (United States); Taylor, P. [Dept. of Psychology, Macquarie University, NSW 2109 (Australia); Shelly, T. [USDA-APHIS, 41-650 Ahiki Street, Waimanalo, HI 96795 (United States)

    2007-03-15

    The sterile insect technique (SIT) is increasingly being used around the world to control Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), the Mediterranean fruit fly as part of an area-wide integrated approach. One option that may improve the effectiveness of the SIT, by increasing the sexual competitiveness of released sterile males, consists of feeding males protein during the post-teneral stage, a diet that increases sexual performance of wild males. We examine the effects of diet on the successive hurdles males must overcome in order to inseminate females, i.e., joining leks, copulating females, having their sperm stored and inhibition of female remating. In addition, we address the effects of diet on post-release foraging success, longevity, and the ability to withstand starvation. While protein feeding universally increases the sexual success of wild males, its effect on sterile males varies with strain, experimental settings, and environmental conditions. In some cases, treatments that resulted in the best sexual performance were significantly associated with increased vulnerability to starvation. However, no particular diet affected the ability of sterile males to find nutrients in the field when these where available. We suggest it may be better to release relatively short-lived flies that are highly competitive, rather than long-lived, sexually ineffective ones. (author) [Spanish] El uso de la tecnica de insecto esteril (TIE) esta aumentando alrededor del mundo para el control de Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), la mosca mediterranea de la fruta como parte de un enfoque integrado por toda el area. Una opcion que puede mejorar la eficiencia de TIE, por medio del aumento de la capacidad de los machos esteriles liberados para competir, consiste en la alimentacion de los machos con proteina durante la etapa de pos-teneral, una dieta que aumenta el desempeno sexual de los machos naturales. Nosotros examinamos los efectos de la dieta sobre los obstaculos sucesivos que los machos tienen que superar para inseminar las hembras, i.e., unir con otros machos en areas para el apareamiento, copula de las hembras, almacenar esperma e inhibir el re-apareamiento de hembras. Ademas discutimos los efectos de la dieta sobre el exito de su actividad forrajera despues de ser liberados, la longevidad y la habilidad para aguantar la inanicion. Mientras que la alimentacion con proteina universalmente aumentan el exito sexual de los machos naturales, su efecto sobre los machos esteriles varia segun la raza, el lugar de los experimentos y las condiciones ambientales. En algunos casos, los tratamientos que resultaron con mejor desempeno sexual fueron asociados significativamente con el aumento de la vulnerabilidad a la inanicion. Sin embargo, ninguna dieta en particular afecto la habilidad de los machos esteriles para encontrar nutrientes en el campo cuando fueron disponibles. Nosotros sugerimos que puede ser mejor el liberar moscas que tienen una vida relativamente corta y que son mas competidoras, en vez de moscas que tienen una vida larga y sexualmente inefectiva. (author)

  6. Male sexual harassment alters female social behaviour towards other females.

    PubMed

    Darden, Safi K; Watts, Lauren

    2012-04-23

    Male harassment of females to gain mating opportunities is a consequence of an evolutionary conflict of interest between the sexes over reproduction and is common among sexually reproducing species. Male Trinidadian guppies Poecilia reticulata spend a large proportion of their time harassing females for copulations and their presence in female social groups has been shown to disrupt female-female social networks and the propensity for females to develop social recognition based on familiarity. In this study, we investigate the behavioural mechanisms that may lead to this disruption of female sociality. Using two experiments, we test the hypothesis that male presence will directly affect social behaviours expressed by females towards other females in the population. In experiment one, we tested for an effect of male presence on female shoaling behaviour and found that, in the presence of a free-swimming male guppy, females spent shorter amounts of time with other females than when in the presence of a free-swimming female guppy. In experiment two, we tested for an effect of male presence on the incidence of aggressive behaviour among female guppies. When males were present in a shoal, females exhibited increased levels of overall aggression towards other females compared with female only shoals. Our work provides direct evidence that the presence of sexually harassing males alters female-female social behaviour, an effect that we expect will be recurrent across taxonomic groups. PMID:21976624

  7. Male sexual harassment alters female social behaviour towards other females

    PubMed Central

    Darden, Safi K.; Watts, Lauren

    2012-01-01

    Male harassment of females to gain mating opportunities is a consequence of an evolutionary conflict of interest between the sexes over reproduction and is common among sexually reproducing species. Male Trinidadian guppies Poecilia reticulata spend a large proportion of their time harassing females for copulations and their presence in female social groups has been shown to disrupt female–female social networks and the propensity for females to develop social recognition based on familiarity. In this study, we investigate the behavioural mechanisms that may lead to this disruption of female sociality. Using two experiments, we test the hypothesis that male presence will directly affect social behaviours expressed by females towards other females in the population. In experiment one, we tested for an effect of male presence on female shoaling behaviour and found that, in the presence of a free-swimming male guppy, females spent shorter amounts of time with other females than when in the presence of a free-swimming female guppy. In experiment two, we tested for an effect of male presence on the incidence of aggressive behaviour among female guppies. When males were present in a shoal, females exhibited increased levels of overall aggression towards other females compared with female only shoals. Our work provides direct evidence that the presence of sexually harassing males alters female–female social behaviour, an effect that we expect will be recurrent across taxonomic groups. PMID:21976624

  8. Simple Y-Autosomal Incompatibilities Cause Hybrid Male Sterility in Reciprocal Crosses Between Drosophila virilis and D. americana

    PubMed Central

    Sweigart, Andrea L.

    2010-01-01

    Postzygotic reproductive isolation evolves when hybrid incompatibilities accumulate between diverging populations. Here, I examine the genetic basis of hybrid male sterility between two species of Drosophila, Drosophila virilis and D. americana. From these analyses, I reach several conclusions. First, neither species carries any autosomal dominant hybrid male sterility alleles: reciprocal F1 hybrid males are perfectly fertile. Second, later generation (backcross and F2) hybrid male sterility between D. virilis and D. americana is not polygenic. In fact, I identified only three genetically independent incompatibilities that cause hybrid male sterility. Remarkably, each of these incompatibilities involves the Y chromosome. In one direction of the cross, the D. americana Y is incompatible with recessive D. virilis alleles at loci on chromosomes 2 and 5. In the other direction, the D. virilis Y chromosome causes hybrid male sterility in combination with recessive D. americana alleles at a single QTL on chromosome 5. Finally, in contrast with findings from other Drosophila species pairs, the X chromosome has only a modest effect on hybrid male sterility between D. virilis and D. americana. PMID:20048051

  9. Blind sterile 2 (bs2), a hypomorphic mutation in Agps, results in cataracts and male sterility in mice

    PubMed Central

    Liegel, R.; Chang, B.; Dubielzig, R.; Sidjanin, D.J.

    2011-01-01

    Blind sterile 2 (bs2) is a spontaneous autosomal recessive mouse mutation exhibiting cataracts and male sterility. Detailed clinical and histological evaluation revealed that bs2 mice have cataracts resulting from severely disrupted lens fiber cells. Analysis of bs2 testes revealed the absence of mature sperm and the presence of large multinucleate cells within the lumens of seminiferous tubules. Linkage analysis mapped the bs2 locus to mouse chromosome 2, approximately 45cM distal from the centromere. Fine mapping established a 3.1Mb bs2 critical region containing 19 candidate genes. Sequence analysis of alkylglycerone-phosphate synthase (Agps), a gene within the bs2 critical region, revealed a G to A substitution at the +5 position of intron 14. This mutation results in two abundantly expressed aberrantly spliced Agps transcripts: Agps?exon14 lacking exon 14 or Agpsexon?13–14 lacking both exons 13 and 14 as well as full-length Agps transcript. Agps is a peroxisomal enzyme which catalyzes the formation of the ether bond during the synthesis of ether lipids. Both aberrantly spliced Agps?exon14 and Agpsexon?13–14 transcripts led to frame shift, premature stop and putative proteins lacking the enzymatic FAD domain. We present evidence that bs2 mice have significantly decreased levels of ether lipids. Human mutations in Agps result in rhizomelic chondrodysplasia punctata type 3 (RCDP3), a disease for which bs2 is the only genetic model. Thus, bs2 is a hypomorphic mutation in Agps, and represents a useful model for investigation of the tissue specificity of ether lipid requirements which will be particularly valuable for elucidating the mechanism of disease phenotypes resulting from ether lipid depletion. PMID:21353609

  10. Mating competitiveness of Aedes albopictus radio-sterilized males in large enclosures exposed to natural conditions.

    PubMed

    Bellini, R; Balestrino, F; Medici, A; Gentile, G; Veronesi, R; Carrieri, M

    2013-01-01

    Mating competitiveness trials have been conducted in large net-screened enclosures (8 by 5 by 2.8 m) built in a natural shaded environment, in the summers of 2006, 2007, 2008, and 2009 in northern Italy. Aedes albopictus (Skuse) males were radio-sterilized by applying gamma radiations at doses in the range 30-60 Gy. Gamma radiation was administered to aged pupae at the rate of 2.3 Gy/min. Reared radiated males (originally collected in Rimini, Forli, Bologna, Matera, Pinerolo) and hybrid radiated males were tested against wild fertile males (originated from eggs collected in Rimini and Cesena) and reared fertile males, in multiple comparisons for mating competitiveness with reared or wild females. The ratio was kept constant at 100-100_100 (fertile males-radiated males_virgin females). Mating competitiveness was estimated through the calculation of the hatching rate of the eggs laid in oviposition traps positioned inside enclosures. No clear effect of the strains tested (reared, wild, or hybrid) was found. Results demonstrated that reducing the radiation dose from 60 to 30 Gy increases males' competitiveness. Laboratory investigations conducted after controversial results in the 2006 preliminary trials, showed that radiation induces precociousness in adult male emergence. PMID:23427657

  11. Directional transfer of a multiple-allele male sterile line in Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee.

    PubMed

    Wang, Qiu Shi; Zhang, Xi; Li, Cheng Yu; Liu, Zhi Yong; Feng, Hui

    2014-06-01

    To produce hybrid seeds of Wutacai (Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee), a "directional transfer program" was designed to breed the multiple-allele male sterile line of Wutacai. A multiple-allele male sterile line of Naibaicai (Brassica campestris L. ssp. chinensis L., S01) was used as the male sterile resource, and an inbred line of Wutacai (WT01) was used as the target line. Recurrent backcrossing was employed to transfer the male sterility and other botanical traits simultaneously, while the genotype was identifiedthrough test crossing. The male sterility was successfully transferred from S01 to WT01. A new male sterile line, GMS-3, with similar botanical traits to WT01, was bred. Four hybrid combinations were generated with GMS-3 as the female parent. One hybrid (C1) that contained the most desirable traits was developed from the new male sterile line. PMID:24987301

  12. Intron hairpin and transitive RNAi mediated silencing of orf H522 transcripts restores male fertility in transgenic male sterile tobacco plants expressing orf H522

    Microsoft Academic Search

    Narasimha Rao Nizampatnam; Viswanathaswamy Dinesh Kumar

    The present work was aimed at developing vector construct(s) suitable for restoring fertility in transgenic male sterile tobacco\\u000a plants expressing male-sterility-inducing ORFH522 in tapetal cell layer (Nizampatnam et al. Planta 229:987–1001, 2009). PTGS vectors that could produce either intron spliced hairpin RNA against the orfH522 or induce silencing of orfH522 by heterologous 3?UTR region were developed using the selected 316 bp

  13. Suppression mechanism of mitochondrial ORF79 accumulation by Rf1 protein in BT-type cytoplasmic male sterile rice

    Microsoft Academic Search

    Tomohiko Kazama; Takahiro Nakamura; Masao Watanabe; Mamoru Sugita; Kinya Toriyama

    2008-01-01

    Summary In BT-type cytoplasmic male sterile rice (Oryza sativa L.) with Chinsurah Boro II cytoplasm, cytoplasmic male sterility (CMS) is caused by an accumulation of the cytotoxic peptide ORF79. The ORF79 protein is expressed from a dicistronic gene atp6-orf79, which exists in addition to the normal atp6 gene in the BT-type mitochondrial genome. The CMS is restored by a PPR

  14. Influence of nuclear background on transcription of a maize mitochondrial region associated with Texas male sterile cytoplasm

    Microsoft Academic Search

    J. C. Kennell; R. P. Wise; D. R. Pring

    1987-01-01

    Transcripts of the maize mitochondrial genes atp6, urf13-T and ORF25 were examined by Northern analysis from five normal (N), Texas male sterile (T), and T male sterile cytoplasm lines restored to fertility. A 5 kb DNA region containing the atp6 promoter is duplicated 5' to urf13-T and ORF25 in T cytoplasm. DNA sequence differences in the 5 kb repeat detected

  15. Cytoplasmic effects on DNA methylation between male sterile lines and the maintainer in wheat (Triticum aestivum L.).

    PubMed

    Ba, Qingsong; Zhang, Gaisheng; Niu, Na; Ma, Shoucai; Wang, Junwei

    2014-10-01

    Male sterile cytoplasm plays an important role in hybrid wheat, and three-line system including male sterile (A line), its maintainer (B line) and restoring (R line) has played a major role in wheat hybrid production. It is well known that DNA methylation plays an important role in gene expression regulation during biological development in wheat. However, no reports are available on DNA methylation affected by different male sterile cytoplasms in hybrid wheat. We employed a methylation-sensitive amplified polymorphism technique to characterize nuclear DNA methylation in three male sterile cytoplasms. A and B lines share the same nucleus, but have different cytoplasms which is male sterile for the A and fertile for the B. The results revealed a relationship of DNA methylation at these sites specifically with male sterile cytoplasms, as well as male sterility, since the only difference between the A lines and B line was the cytoplasm. The DNA methylation was markedly affected by male sterile cytoplasms. K-type cytoplasm affected the methylation to a much greater degree than T-type and S-type cytoplasms, as indicated by the ratio of methylated sites, ratio of fully methylated sites, and polymorphism between A lines and B line for these cytoplasms. The genetic distance between the cytoplasm and nucleus for the K-type is much greater than for the T- and S-types because the former is between Aegilops genus and Triticum genus and the latter is within Triticum genus between Triticum spelta and Triticum timopheevii species. Thus, this difference in genetic distance may be responsible for the variation in methylation that we observed. PMID:24875418

  16. A chimeric gene containing the 5? portion of atp6 is associated with cytoplasmic male-sterility of rice

    Microsoft Academic Search

    Koh-ichi Kadowaki; Takeshi Suzuki; Shigeru Kazama

    1990-01-01

    Three ATPase subunit 6 (atp6) genes of rice mitochondria were isolated, one from normal and two from cms-Bo male-sterile cytoplasms, in order to determine whether the extra atp6 gene in cms-Bo rice plays a role in cytoplasmic male-sterility (CMS). The nucleotide sequences of all three genes were determined and analysis showed a chimeric atp6 gene (urf-rmc) as well as a

  17. Anther-specific carbohydrate supply and restoration of metabolically engineered male sterility

    PubMed Central

    Engelke, T.; Hirsche, J.; Roitsch, T.

    2010-01-01

    Male-sterile plants are used in hybrid breeding as well as for gene confinement for genetically modified plants in field trials and agricultural production. Apart from naturally occurring mutations leading to male sterility, biotechnology has added new possibilities for obtaining male-sterile plants, although so far only one system is used in practical breeding due to limitations in propagating male-sterile plants without segregations in the next generation or insufficient restoration of fertility when fruits or seeds are to be harvested from the hybrid varieties. Here a novel mechanism of restoration for male sterility is presented that has been achieved by interference with extracellular invertase activity, which is normally specifically expressed in the anthers to supply the developing microspores with carbohydrates. Microspores are symplastically isolated in the locular space of the anthers, and thus an unloading pathway of assimilates via the apoplasmic space is mandatory for proper development of pollen. Antisense repression of the anther-specific cell wall invertase or interference with invertase activity by expressing a proteinacious inhibitor under the control of the anther-specific invertase promoter results in a block during early stages of pollen development, thus causing male sterility without having any pleiotropic effects. Restoration of fertility was successfully achieved by substituting the down-regulated endogenous plant invertase activity by a yeast invertase fused to the N-terminal portion of potato-derived vacuolar protein proteinase II (PiII–ScSuc2), under control of the orthologous anther-specific invertase promoter Nin88 from tobacco. The chimeric fusion PiII–ScSuc2 is known to be N-glycosylated and efficiently secreted from plant cells, leading to its apoplastic location. Furthermore, the Nin88::PiII-ScSuc2 fusion does not show effects on pollen development in the wild-type background. Thus, such plants can be used as paternal parents of a hybrid variety, thereby the introgression of Nin88::PiII-ScSuc2 to the hybrid is obtained and fertility is restored. In order to broaden the applicability of this male sterility/restoration system to other plant species, a phylogenic analysis of plant invertases(?-fructofuranosidases) and related genes of different species was carried out. This reveals a specific clustering of the cell wall invertases with anther-specific expression for dicotyl species and another cluster for monocotyl plants. Thus, in both groups of plants, there seems to be a kind of co-evolution, but no recent common ancestor of these members of the gene family. These findings provide a helpful orientation to classify corresponding candidate genes in further plant species, in addition to the species analysed so far (Arabidopsis, tobacco, tomato, potato, carrots, rice, and wheat). PMID:20427415

  18. Reassessing Adolescent Male Sexual and Reproductive Health in the United States: Research and Recommendations

    Microsoft Academic Search

    Laura Duberstein Lindberg; Adam Sonfield; Alison Gemmill

    2008-01-01

    Adolescent males are practicing safer sexual behaviors and experiencing healthier outcomes than their predecessors. In recent years, adolescent males have tended to start having sex later in life, have fewer sexual partners, use condoms and other contraceptive methods more often, and father fewer children. Yet sexual activity during adolescence remains the norm, and thus adolescent sexual and reproductive health (SRH)

  19. Dominance, Coloration, and Social and Sexual Behavior in Male Drills Mandrillus leucophaeus

    Microsoft Academic Search

    Jill S. Marty; James P. Higham; Elizabeth L. Gadsby; Caroline Ross

    2009-01-01

    Sexual selection has driven the evolution and elaboration of a wide variety of displays and ornaments in male nonhuman primates,\\u000a including capes, cheek flanges, and sexual coloration. Among the most sexually dimorphic of all primates is the drill (Mandrillus leucophaeus), the males of which can be 3 times the mass of females, possess large canines, and exhibit extremely bright sexual

  20. Control of Male Sexual Behavior and Sexual Orientation in Drosophila by the fruitless Gene

    Microsoft Academic Search

    Lisa C Ryner; Stephen F Goodwin; Diego H Castrillon; Anuranjan Anand; Adriana Villella; Bruce S Baker; Jeffrey C Hall; Barbara J Taylor; Steven A Wasserman

    1996-01-01

    Sexual orientation and courtship behavior in Drosophila are regulated by fruitless (fru), the first gene in a branch of the sex-determination hierarchy functioning specifically in the central nervous system (CNS). The phenotypes of new fru mutants encompass nearly all aspects of male sexual behavior. Alternative splicing of fru transcripts produces sex-specific proteins belonging to the BTB-ZF family of transcriptional regulators.

  1. Sexual Function in Males After Radiotherapy for Rectal Cancer

    SciTech Connect

    Bruheim, Kjersti, E-mail: Kjersti.bruheim@medisin.uio.n [Oslo University Hospital, Ulleval Cancer Centre, Oslo (Norway); Guren, Marianne G. [Oslo University Hospital, Ulleval Cancer Centre, Oslo (Norway); Dahl, Alv A. [Oslo University Hospital, Department of Clinical Cancer Research, the Norwegian Radium Hospital, Oslo (Norway); Faculty of Medicine, University of Oslo, Oslo (Norway); Skovlund, Eva [School of Pharmacy, University of Oslo, Oslo (Norway); Balteskard, Lise [University Hospital of Northern Norway, Tromso (Norway); Carlsen, Erik [Oslo University Hospital, Department of Gastrointestinal Surgery, Ulleval, Oslo (Norway); Fossa, Sophie D. [Oslo University Hospital, Department of Clinical Cancer Research, the Norwegian Radium Hospital, Oslo (Norway); Faculty of Medicine, University of Oslo, Oslo (Norway); Tveit, Kjell Magne [Oslo University Hospital, Ulleval Cancer Centre, Oslo (Norway); Faculty of Medicine, University of Oslo, Oslo (Norway)

    2010-03-15

    Purpose: Knowledge of sexual problems after pre- or postoperative radiotherapy (RT) with 50 Gy for rectal cancer is limited. In this study, we aimed to compare self-rated sexual functioning in irradiated (RT+) and nonirradiated (RT-) male patients at least 2 years after surgery for rectal cancer. Methods and Materials: Patients diagnosed with rectal cancer from 1993 to 2003 were identified from the Norwegian Rectal Cancer Registry. Male patients without recurrence at the time of the study. The International Index of Erectile Function, a self-rated instrument, was used to assess sexual functioning, and serum levels of serum testosterone were measured. Results: Questionnaires were returned from 241 patients a median of 4.5 years after surgery. The median age was 67 years at survey. RT+ patients (n = 108) had significantly poorer scores for erectile function, orgasmic function, intercourse satisfaction, and overall satisfaction with sex life compared with RT- patients (n = 133). In multiple age-adjusted analysis, the odds ratio for moderate-severe erectile dysfunction in RT+ patients was 7.3 compared with RT- patients (p <0.001). Furthermore, erectile dysfunction of this degree was associated with low serum testosterone (p = 0.01). Conclusion: RT for rectal cancer is associated with significant long-term effects on sexual function in males.

  2. Selection for alternative male reproductive tactics alters intralocus sexual conflict.

    PubMed

    Plesnar Bielak, Agata; Skrzynecka, Anna M; Miler, Krzysztof; Radwan, Jacek

    2014-07-01

    Intralocus sexual conflict (IASC) arises when fitness optima for a shared trait differ between the sexes; such conflict may help maintain genetic variation within populations. Sex-limited expression of sexually antagonistic traits may help resolve the conflict, but the extent of this resolution remains a subject of debate. In species with alternative male reproductive tactics, unresolved conflict should manifest more in a more sexually dimorphic male phenotype. We tested this prediction in the bulb mite (Rhizoglyphus robini), a species in which aggressive fighters coexist with benign scramblers. To do this, we established replicated lines in which we increased the proportion of each of the alternative male morphs using artificial selection. After approximately 40 generations, the proportion of fighters and scramblers stabilized at >0.9 in fighter- and scrambler-selected lines, respectively. We then measured several female fitness components. As predicted by IASC theory, female fecundity and longevity were lower in lines selected for fighters and higher in lines selected for scramblers. This finding indicates that sexually selected phenotypes are associated with an ontogenetic conflict that is not easily resolved. Furthermore, we suggest that IASC may be an important mechanism contributing to the maintenance of genetic variation in the expression of alternative reproductive tactics. PMID:24641007

  3. Male gametogenesis and sterility in garlic (Allium sativum L.): barriers on the way to fertilization and seed production.

    PubMed

    Shemesh Mayer, Einat; Winiarczyk, Krystyna; B?aszczyk, Lidia; Kosmala, Arkadiusz; Rabinowitch, Haim D; Kamenetsky, Rina

    2013-01-01

    Commercial cultivars of garlic (Allium sativum) do not produce flowers and seed; hence, information on microgametogenesis and genetic knowledge of this important crop is unavailable. Recently, physiological studies enabled flowering and fertility restoration in garlic bolting genotypes by environmental manipulations, thus broadening of the genetic variation and facilitating genetic studies. The present report provides first detailed description of the development of male gametophytes in 11 garlic genotypes varying in their fertility traits. Morphological and anatomical studies revealed completely fertile genotypes, as well as variation in anther and pollen development and disruption of the male organs and gametes at different developmental stages. Three types of plant sterility were observed, including complete sterility, male sterility and environmentally induced male sterility. The ITS1 and ITS2 regions of rRNA of the studied genotypes proved to be strongly conservative and thus did not correspond with the phenotypic expression of fertility or sterility in garlic. On the other hand, two-dimensional protein separation maps revealed significant differences between fertile and sterile genotypes, as well as between developmental stages of microsporogenesis. Further research is needed to investigate the internal mechanisms and environmental component of garlic sterility, as well as the possible molecular markers of these traits. PMID:22986686

  4. Exposure to harsh parenting and pornography as explanations for males' sexual coercion and females' sexual victimization.

    PubMed

    Simons, Leslie Gordon; Simons, Ronald L; Lei, Man-Kit; Sutton, Tara E

    2012-01-01

    Sexual violence against women is a major concern to researchers and policy makers, as well as to the general public. This study uses a sample of more than 2,000 college students to investigate the extent to which exposure to harsh parenting practices and sexually explicit materials contributes to perpetration and victimization. Findings indicate that frequent corporal punishment in the family of origin combined with consumption of pornographic materials increased the probability that males reported engaging in coercive sexual practices. For females, both frequent corporal punishment and exposure to paternal hostility combined with consumption of pornographic materials were associated with higher levels of reported sexual victimization. These results provide increased understanding of the impact of pornography use among a nonclinical sample, as well as the consequences of experiencing harsh corporal punishment in one's family of origin, on the sexual victimization of females. PMID:22852438

  5. Olfactory threshold to bourgeonal and sexual desire1 in young adult males.2

    E-print Network

    Cesare, Bernardo

    1 Olfactory threshold to bourgeonal and sexual desire1 in young adult males.2 3 Giancarlo Ottaviano; Bourgeonal; Young adult; Male sexual desire; OR1D2 SNPs22 #12;2 Abstract Olfactory receptors have been found of5 normosmic young adult males. We have hypothesized, in fact, that a lower sexual desire could be6

  6. Survivorship: sexual dysfunction (male), version 1.2013.

    PubMed

    Denlinger, Crystal S; Carlson, Robert W; Are, Madhuri; Baker, K Scott; Davis, Elizabeth; Edge, Stephen B; Friedman, Debra L; Goldman, Mindy; Jones, Lee; King, Allison; Kvale, Elizabeth; Langbaum, Terry S; Ligibel, Jennifer A; McCabe, Mary S; McVary, Kevin T; Melisko, Michelle; Montoya, Jose G; Mooney, Kathi; Morgan, Mary Ann; O'Connor, Tracey; Paskett, Electra D; Raza, Muhammad; Syrjala, Karen L; Urba, Susan G; Wakabayashi, Mark T; Zee, Phyllis; McMillian, Nicole; Freedman-Cass, Deborah

    2014-03-01

    Various anticancer treatments, especially those directed toward the pelvis, can damage blood vessels and reduce circulation of blood to the penis and/or damage the autonomic nervous system, resulting in higher rates of erectile dysfunction in survivors than in the general population. In addition, hormonal therapy can contribute to sexual problems, as can depression and anxiety, which are common in cancer survivors. This section of the NCCN Guidelines for Survivorship provides screening, evaluation, and treatment recommendations for male sexual problems, namely erectile dysfunction. PMID:24616541

  7. Survivorship: Sexual Dysfunction (Male), Version 1.2013

    PubMed Central

    Denlinger, Crystal S.; Carlson, Robert W.; Are, Madhuri; Baker, K. Scott; Davis, Elizabeth; Edge, Stephen B.; Friedman, Debra L.; Goldman, Mindy; Jones, Lee; King, Allison; Kvale, Elizabeth; Langbaum, Terry S.; Ligibel, Jennifer A.; McCabe, Mary S.; McVary, Kevin T.; Melisko, Michelle; Montoya, Jose G.; Mooney, Kathi; Morgan, Mary Ann; O’Connor, Tracey; Paskett, Electra D.; Raza, Muhammad; Syrjala, Karen L.; Urba, Susan G.; Wakabayashi, Mark T.; Zee, Phyllis; McMillian, Nicole; Freedman-Cass, Deborah

    2015-01-01

    Various anticancer treatments, especially those directed toward the pelvis, can damage blood vessels and reduce circulation of blood to the penis and/or damage the autonomic nervous system, resulting in higher rates of erectile dysfunction in survivors than in the general population. In addition, hormonal therapy can contribute to sexual problems, as can depression and anxiety, which are common in cancer survivors. This section of the NCCN Guidelines for Survivorship provides screening, evaluation, and treatment recommendations for male sexual problems, namely erectile dysfunction. PMID:24616541

  8. D-glufosinate as a male sterility agent for hybrid seed production.

    PubMed

    Hawkes, Tim; Pline-Srnic, Wendy; Dale, Richard; Friend, Emma; Hollinshead, Tricia; Howe, Peter; Thompson, Paul; Viner, Russell; Greenland, Andy

    2011-04-01

    A chemical male sterility system based on anther-localized conversion of the inactive D-enantiomer of the herbicide, glufosinate (2-amino-4-(methylphosphinyl)-butanoate) to the phytotoxic L is described. Highly pure D-glufosinate was isolated in >98% enantiomeric excess from the racemate via fermentation with a strain of Escherichia coli expressing the PAT (L-glufosinate N-acetyl transferase) gene and purification of the unreacted D-enantiomer from the broth by ion exchange. A modified (F58K, M213S) form of the D-amino acid oxidase (DAAO) (EC 1.4.3.3) from Rhodosporidium toruloides was designed, tested in vitro and found to efficiently oxidize D-glufosinate to its 2-oxo derivative [2-oxo-4-(methylphosphinyl)-butanoic acid]. Tobacco (Nicotiana tabacum) plants were transformed to express this modified oxidase under control of the TAP1 tapetum-specific promoter. A number of the resultant transgenic lines exhibited complete male sterility that persisted for two or more weeks immediately following foliar treatment with 75 or 200 g/ha of D-glufosinate without exhibiting obvious phytotoxic symptoms or any measurable decline in female fertility. Similarly, plants containing the same construct and, additionally, a PAT gene expressed from a plastocyanin promoter exhibited significantly reduced male fertility and no reduction in female fertility following foliar application of racemic glufosinate. Thus, foliar application of d-glufosinate either purified or as the commercial herbicide, combined with anther expression of a modified DAAO promises to provide a cost-effective conditional chemical male sterility system with the characteristics necessary for practical F? hybrid seed production. PMID:20678098

  9. New cytoplasmic male sterility sources in common wheat: Their genetical and breeding considerations.

    PubMed

    Panayotov, I

    1980-07-01

    Nuclei from Triticum aestivum L. cultivars 'Penjamo 62' and 'Siete Cerros 66' were introduced into the cytoplasms of different species of Aegilops and some subspecies (varieties) of T. dicoccoides by backcrossing. The sterile alloplasmic lines obtained were compared with the normal cultivars used as the recurrent pollen parents. According to the cytoplasmic effect, these cytoplasms were subdivided into three main groups. The first group possesses C(u) type cytoplasm, the second one possesses M type and the third group includes S, C and G type. Promising male sterile cytoplasms for hybrid wheat production were found in Ae. mutica, Ae. triuncialis and T. dicoccoides var. 'spontaneovillosum'. Based on these results and other information some conjectures were made concerning hybrid wheat breeding and phylogenetic differentiations of the cytoplasm. PMID:24305794

  10. Sexual Orientation Related Differences in Cortical Thickness in Male Individuals

    PubMed Central

    Abé, Christoph; Johansson, Emilia; Allzén, Elin; Savic, Ivanka

    2014-01-01

    Previous neuroimaging studies demonstrated sex and also sexual orientation related structural and functional differences in the human brain. Genetic information and effects of sex hormones are assumed to contribute to the male/female differentiation of the brain, and similar effects could play a role in processes influencing human's sexual orientation. However, questions about the origin and development of a person's sexual orientation remain unanswered, and research on sexual orientation related neurobiological characteristics is still very limited. To contribute to a better understanding of the neurobiology of sexual orientation, we used magnetic resonance imaging (MRI) in order to compare regional cortical thickness (Cth) and subcortical volumes of homosexual men (hoM), heterosexual men (heM) and heterosexual women (heW). hoM (and heW) had thinner cortices primarily in visual areas and smaller thalamus volumes than heM, in which hoM and heW did not differ. Our results support previous studies, which suggest cerebral differences between hoM and heM in regions, where sex differences have been reported, which are frequently proposed to underlie biological mechanisms. Thus, our results contribute to a better understanding of the neurobiology of sexual orientation. PMID:25479554

  11. Sexually Degrading Music Videos and Lyrics: Their Effects on Males’ Aggression and Endorsement of Rape Myths and Sexual Stereotypes

    Microsoft Academic Search

    Eric L. Sprankle; Christian M. End; Miranda N. Bretz

    2012-01-01

    Utilizing a 2 (lyrics: present or absent) × 2 (images: present or absent) design, this study examined the unique effects of sexually degrading music videos and music lyrics on males’ aggressive behavior toward women, as well as males’ endorsement of rape myths and sexual stereotypes. Under the guise of a media memory study, 187 male undergraduate students were randomly assigned

  12. Sexual cannibalism and mate choice decisions in wolf spiders: influence of male size and secondary sexual characters

    Microsoft Academic Search

    Matthew H. Persons; George W. Uetz

    2005-01-01

    Sexual cannibalism may influence expression of elaborate male traits by either reinforcing or opposing sexual selection. Male Schizocosa ocreata (Hentz) wolf spiders (Lycosidae) have tufts of bristles on the first pair of legs that may function as a condition-indicating signal trait. We paired virgin and previously mated adult females with males under seminatural conditions (laboratory containers with leaf litter). For

  13. Wing Morphometry and Acoustic Signals in Sterile and Wild Males: Implications for Mating Success in Ceratitis capitata

    PubMed Central

    de Souza, João Maria Gomes Alencar; Molina, Wagner Franco; de Almeida, Lúcia Maria; de Gouveia, Milson Bezerra; de Macêdo, Francisco Pepino; Laumann, Raul Alberto; Paranhos, Beatriz Aguiar Jordão

    2015-01-01

    The sterile insect technique (SIT) is widely utilized in the biological control of fruit flies of the family Tephritidae, particularly against the Mediterranean fruit fly. This study investigated the interaction between mating success and morphometric variation in the wings and the production of acoustic signals among three male groups of Ceratitis capitata (Wiedemann): (1) wild males, (2) irradiated with Co-60 (steriles), and (3) irradiated (steriles) and treated with ginger oil. The canonical variate analysis discriminated two groups (males irradiated and males wild), based on the morphological shape of the wings. Among males that emit buzz signals, wild males obtained copulation more frequently than males in Groups 2 and 3. The individuals of Group 3 achieved more matings than those in Group 2. Wild males displayed lower pulse duration, higher intervals between pulses, and higher dominant frequency. Regarding the reproductive success, the morphological differences in the wings' shape between accepted and nonaccepted males are higher in wild males than in the irradiated ones. The present results can be useful in programs using the sterile insect technique for biological control of C. capitata. PMID:26075293

  14. Wing Morphometry and Acoustic Signals in Sterile and Wild Males: Implications for Mating Success in Ceratitis capitata.

    PubMed

    de Souza, João Maria Gomes Alencar; de Lima-Filho, Paulo Augusto; Molina, Wagner Franco; de Almeida, Lúcia Maria; de Gouveia, Milson Bezerra; de Macêdo, Francisco Pepino; Laumann, Raul Alberto; Paranhos, Beatriz Aguiar Jordão

    2015-01-01

    The sterile insect technique (SIT) is widely utilized in the biological control of fruit flies of the family Tephritidae, particularly against the Mediterranean fruit fly. This study investigated the interaction between mating success and morphometric variation in the wings and the production of acoustic signals among three male groups of Ceratitis capitata (Wiedemann): (1) wild males, (2) irradiated with Co-60 (steriles), and (3) irradiated (steriles) and treated with ginger oil. The canonical variate analysis discriminated two groups (males irradiated and males wild), based on the morphological shape of the wings. Among males that emit buzz signals, wild males obtained copulation more frequently than males in Groups 2 and 3. The individuals of Group 3 achieved more matings than those in Group 2. Wild males displayed lower pulse duration, higher intervals between pulses, and higher dominant frequency. Regarding the reproductive success, the morphological differences in the wings' shape between accepted and nonaccepted males are higher in wild males than in the irradiated ones. The present results can be useful in programs using the sterile insect technique for biological control of C. capitata. PMID:26075293

  15. Effect of three larval diets on larval development and male sexual performance of Anopheles gambiae s.s.

    PubMed

    Yahouédo, Gildas A; Djogbénou, Luc; Saïzonou, Jacques; Assogba, Bénoît S; Makoutodé, Michel; Gilles, Jeremie R L; Maïga, Hamidou; Mouline, Karine; Soukou, Bhonna K; Simard, Frédéric

    2014-04-01

    Population replacement/elimination strategies based on mass-release of sterile or otherwise genetically modified (male) mosquitoes are being considered in order to expand the malaria vector control arsenal on the way to eradication. A challenge in this context, is to produce male mosquitoes that will be able to compete and mate with wild females more efficiently than their wild counterparts, i.e. high fitness males. This study explored the effect of three larval food diets developed by the International Atomic Energy Agency on the overall fitness and mating performance of male Anopheles gambiae s.s. mosquitoes (Kisumu strain). Larval development (pupation and emergence rate, development time) was monitored, and adult wing length and energy reserves at emergence (i.e. lipids, sugars, glycogen and proteins) were measured. Male sexual performance was assessed through an insemination test whereby one male and 10 virgin females were maintained together in the same cage in order to record the number of inseminated females per 24h. Our results show that males reared on Diets 2 and 3 performed best during larval development. Males provided with treatment 2.2 had a shorter development time and performed best in insemination tests. However, these males had the lowest overall lifespan, suggesting a trade-off between longevity and sexual performances which needs to be taken into consideration when planning release. The results from this work were discussed in the context of sterile insect techniques or genetic control methods which is today one of the strategy in the overall mosquito control and elimination efforts. PMID:24291460

  16. Polymorphism in hybrid male sterility in wild-derived Mus musculus musculus strains on proximal chromosome 17.

    PubMed

    Vyskocilová, Martina; Prazanová, Gabriela; Piálek, Jaroslav

    2009-02-01

    The hybrid sterility-1 (Hst1) locus at Chr 17 causes male sterility in crosses between the house mouse subspecies Mus musculus domesticus (Mmd) and M. m. musculus (Mmm). This locus has been defined by its polymorphic variants in two laboratory strains (Mmd genome) when mated to PWD/Ph mice (Mmm genome): C57BL/10 (carrying the sterile allele) and C3H (fertile allele). The occurrence of sterile and/or fertile (wild Mmm x C57BL)F1 males is evidence that polymorphism for this trait also exists in natural populations of Mmm; however, the nature of this polymorphism remains unclear. Therefore, we derived two wild-origin Mmm strains, STUS and STUF, that produce sterile and fertile males, respectively, in crosses with C57BL mice. To determine the genetic basis underlying male fertility, the (STUS x STUF)F1 females were mated to C57BL/10 J males. About one-third of resulting hybrid males (33.8%) had a significantly smaller epididymis and testes than parental animals and lacked spermatozoa due to meiotic arrest. A further one-fifth of males (20.3%) also had anomalous reproductive traits but produced some spermatozoa. The remaining fertile males (45.9%) displayed no deviation from values found in parental individuals. QTL analysis of the progeny revealed strong associations of male fitness components with the proximal end of Chr 17, and a significant effect of the central section of Chr X on testes mass. The data suggest that genetic incompatibilities associated with male sterility have evolved independently at the proximal end of Chr 17 and are polymorphic within both Mmd and Mmm genomes. PMID:19123034

  17. Misregulation of spermatogenesis genes in Drosophila hybrids is lineage-specific and driven by the combined effects of sterility and fast male regulatory divergence.

    PubMed

    Gomes, S; Civetta, A

    2014-09-01

    Hybrid male sterility is a common outcome of crosses between different species. Gene expression studies have found that a number of spermatogenesis genes are differentially expressed in sterile hybrid males, compared with parental species. Late-stage sperm development genes are particularly likely to be misexpressed, with fewer early-stage genes affected. Thus, a link has been posited between misexpression and sterility. A more recent alternative explanation for hybrid gene misexpression has been that it is independent of sterility and driven by divergent evolution of male-specific regulatory elements between species (faster male hypothesis). The faster male hypothesis predicts that misregulation of spermatogenesis genes should be independent of sterility and approximately the same in both hybrids, whereas sterility should only affect gene expression in sterile hybrids. To test the faster male hypothesis vs. the effect of sterility on gene misexpression, we analyse spermatogenesis gene expression in different species pairs of the Drosophila phylogeny, where hybrid male sterility occurs in only one direction of the interspecies cross (i.e. unidirectional sterility). We find significant differences among genes in misexpression with effects that are lineage-specific and caused by sterility or fast male regulatory divergence. PMID:24898362

  18. Engineering cytoplasmic male sterility via the chloroplast genome by expression of {beta}-ketothiolase.

    PubMed

    Ruiz, Oscar N; Daniell, Henry

    2005-07-01

    While investigating expression of the polydroxybutyrate pathway in transgenic chloroplasts, we addressed the specific role of beta-ketothiolase. Therefore, we expressed the phaA gene via the chloroplast genome. Prior attempts to express the phaA gene in transgenic plants were unsuccessful. We studied the effect of light regulation of the phaA gene using the psbA promoter and 5' untranslated region, and evaluated expression under different photoperiods. Stable transgene integration into the chloroplast genome and homoplasmy were confirmed by Southern analysis. The phaA gene was efficiently transcribed in all tissue types examined, including leaves, flowers, and anthers. Coomassie-stained gel and western blots confirmed hyperexpression of beta-ketothiolase in leaves and anthers, with proportionately high levels of enzyme activity. The transgenic lines were normal except for the male-sterile phenotype, lacking pollen. Scanning electron microscopy revealed a collapsed morphology of the pollen grains. Floral developmental studies revealed that transgenic lines showed an accelerated pattern of anther development, affecting their maturation, and resulted in aberrant tissue patterns. Abnormal thickening of the outer wall, enlarged endothecium, and vacuolation affected pollen grains and resulted in the irregular shape or collapsed phenotype. Reversibility of the male-sterile phenotype was observed under continuous illumination, resulting in viable pollen and copious amount of seeds. This study results in the first engineered cytoplasmic male-sterility system in plants, offers a new tool for transgene containment for both nuclear and organelle genomes, and provides an expedient mechanism for F(1) hybrid seed production. PMID:16009998

  19. SRY alone can induce normal male sexual differentiation

    SciTech Connect

    Lopez, M.; Torres, L.; Cervantes, A. [HGM SSa. Facultad de Medicina, UNAM, MX (United States)] [and others

    1995-01-30

    Most individuals with the rare 46,XX male {open_quotes}syndrome{close_quotes} arise due to an unequal interchange between Xp and Yp termini during paternal meiosis. The pattern of Y-sequences in these patients varies considerably, but very few cases have been reported showing only SRY. The phenotype in these patients is also variable ranging from severe impairment of the external genitalia through hypospadias and/or cryptorchidism to occasional normal male phenotype. We report a Mexican 46,XX male patient without genital ambiguities in whom DNA analysis showed the presence of SRY and the absence of ZFY. We conclude that in this case SRY alone was enough for complete male sexual differentiation. 25 refs., 1 fig.

  20. Sexual selection and the fitness consequences of male body size in the seed beetle Stator limbatus

    Microsoft Academic Search

    UDO M. SAVALLI; CHARLES W. FOX

    1998-01-01

    We examined sexual selection on male body size in a laboratory population of the seed beetle,Stator limbatus, and the fitness consequences to females of mating with larger males. Large males produced larger ejaculates than small males. Both males and females lost body weight as a consequence of breeding, and large males lost more weight than small males. The amount of

  1. Sexually dimorphic RB inactivation underlies mesenchymal glioblastoma prevalence in males

    PubMed Central

    Sun, Tao; Warrington, Nicole M.; Luo, Jingqin; Brooks, Michael D.; Dahiya, Sonika; Snyder, Steven C.; Sengupta, Rajarshi; Rubin, Joshua B.

    2014-01-01

    The prevalence of brain tumors in males is common but unexplained. While sex differences in disease are typically mediated through acute sex hormone actions, sex-specific differences in brain tumor rates are comparable at all ages, suggesting that factors other than sex hormones underlie this discrepancy. We found that mesenchymal glioblastoma (Mes-GBM) affects more males as the result of cell-intrinsic sexual dimorphism in astrocyte transformation. We used astrocytes from neurofibromin-deficient (Nf1–/–) mice expressing a dominant-negative form of the tumor suppressor p53 (DNp53) and treated them with EGF as a Mes-GBM model. Male Mes-GBM astrocytes exhibited greater growth and colony formation compared with female Mes-GBM astrocytes. Moreover, male Mes-GBM astrocytes underwent greater tumorigenesis in vivo, regardless of recipient mouse sex. Male Mes-GBM astrocytes exhibited greater inactivation of the tumor suppressor RB, higher proliferation rates, and greater induction of a clonogenic, stem-like cell population compared with female Mes-GBM astrocytes. Furthermore, complete inactivation of RB and p53 in Mes-GBM astrocytes resulted in equivalent male and female tumorigenic transformation, indicating that intrinsic differences in RB activation are responsible for the predominance of tumorigenic transformation in male astrocytes. Together, these results indicate that cell-intrinsic sex differences in RB regulation and stem-like cell function may underlie the predominance of GBM in males. PMID:25083989

  2. RFLP analysis of mitochondrial DNA from cytoplasmic male-sterile lines of pearl millet

    Microsoft Academic Search

    R. Rajeshwari; S. Sivaramakrishnan; R. L. Smith; N. C. Subrahmanyam

    1994-01-01

    Mitochondrial DNA (mtDNA) from 13 cytoplasmic male-sterile (cms) lines from diverse sources were characterized by Southern blot hybridization to pearl millet and maize mtDNA probes. Hybridization patterns of mtDNA digested with PstI, BamHI, SmaI or XhoI and probed with 13.6-, 10.9-, 9.7- or 4.7-kb pearl millet mtDNA clones revealed similarities among the cms lines 5141 A and ICMA 1 (classified

  3. Effects of Rootstocks on Cryotolerance and Overwintering Survivorship of Genic Male Sterile Lines in Upland Cotton (Gossypium hirsutum L.)

    PubMed Central

    Zhang, Xin; Zhang, Zhiyong; Wang, Qinglian; Chen, Peng; Chen, Guoping; Zhou, Ruiyang

    2013-01-01

    Grafting desirable scion on stress-tolerant rootstocks provides an opportunity to improve the cryotolerance of scion. Genic male sterile (GMS) lines of plant could be used as sterile line and maintainer in breeding, and they have the conspicuous characteristics that the fertility of which is easy to regain but hard to maintain by sexual reproduction. In order to maintain the fertility of GMS cotton by means of its perennial growth on the basis of frostless winters in Nanning, Guangxi autonomous region, GMS line A4 was grafted onto 7 cryotolerant rootstocks (F118, F697, F098, F112, F113, P098 and P113), and the cryotolerance and the overwintering survivorship of scions were investigated. In consequence, when compared with control (self-grafted A4), the relative conductivity of the grafted plants in shoot bark was reduced (8.80%), the content of soluble sugar, soluble protein and free proline were higher, 25.00, 1.55, 3.46%, respectively; the overwintering survival rate and the height of regeneration bud under field condition of grafted plants were higher, 10.44, 15.75%, respectively; the order of the grafted plants based on the average subordinate function value of overwintering survivorship was A4/F113>A4/F118>A4/F098>A4/F697>A4/F112>A4/P098>A4/P113>A4/A4(CK); the correlation analyses indicated that the physiological parameters of cryotolerance could be used for forecasting the overwintering survivorship, and the relative conductivity could be chosen as the first physiological parameter for forecasting cryotolerance or overwintering survivorship. The results indicate that the cryotolerance and the overwintering survivorship of GMS cotton could be improved by grafting, and F113 appeared to be a valuable rootstock. PMID:23667634

  4. A recessive gene controlling male sterility sensitive to short daylength/low temperature in wheat (Triticum aestivum L.)*

    PubMed Central

    Chen, Xiao-dong; Sun, Dong-fa; Rong, De-fu; Peng, Jun-hua; Li, Cheng-dao

    2011-01-01

    Utilization of a two-line breeding system via photoperiod-thermo sensitive male sterility has a great potential for hybrid production in wheat (Triticum aestivum L.). 337S is a novel wheat male sterile line sensitive to both short daylength/low temperature and long daylength/high temperature. Five F2 populations derived from the crosses between 337S and five common wheat varieties were developed for genetic analysis. All F1’s were highly fertile while segregation occurred in the F2 populations with a ratio of 3 fertile:1 sterile under short daylength/low temperature. It is shown that male sterility in 337S was controlled by a single recessive gene, temporarily designated as wptms3. Bulked segregant analysis (BSA) coupled with simple sequence repeat (SSR) markers was applied to map the sterile gene using one mapping population. The wptms3 gene was mapped to chromosome arm 1BS and flanked by Xgwm413 and Xgwm182 at a genetic distance of 3.2 and 23.5 cM, respectively. The accuracy and efficiency of marker-assisted selection were evaluated and proved essential for identifying homozygous recessive male sterile genotypes of the wptms3 gene in F2 generation. PMID:22042660

  5. Comparing Female and Male Perpetrators' Modus Operandi: Victims' Reports of Sexual Abuse.

    ERIC Educational Resources Information Center

    Kaufman, Keith L.; And Others

    1995-01-01

    Investigated similarities and differences in modus operandi of female and male child sexual abusers by comparing victims of female and male perpetrators. Females were more often involved with males in co-offender situations and were more likely to exploit victims. Males were more sexually invasive and more likely to use bribes to obtain victim…

  6. Male Syrian hamsters demonstrate a conditioned place preference for sexual behavior and female chemosensory stimuli

    E-print Network

    Sisk, Cheryl

    Male Syrian hamsters demonstrate a conditioned place preference for sexual behavior and female induce a CPP in male Syrian hamsters. As male Syrian hamsters are an animal model commonly used. Experiment 1 tested the prediction that male hamsters show a CPP for sexual behavior. Female chemosensory

  7. Sequencing and annotation of the chloroplast DNAs and identification of polymorphisms distinguishing normal male-fertile and male-sterile cytoplasms of onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due the biennial generation time of onion, classical crossing takes at least four years to classify cytoplasms as normal (N) male-fertile or male-sterile (S). Molecular markers in the organellar DNAs that distinguish N and S cytoplasms are useful to reduce the time required to classify onion cytopla...

  8. Restoration of fertility in cytoplasmic male sterile (CMS) Nicotiana Sylvestris by fusion with X-irradiated N. tabacum protoplasts

    Microsoft Academic Search

    D. Aviv; E. Galun

    1980-01-01

    Restoration of male fertility was achieved by fusing protoplasts from male sterile (CMS) Nicotiana sylvestris plants with X-irradiated protoplasts derived from fertile N. tabacum plants. The CMS N. sylvestris plants were derived from a previous somatic hybridization experiment and contained alien (Line 92) cytoplasm. About one quarter of the regenerated plants were found to be cybrids. i.e. they consisted of

  9. Genetics of hybrid male sterility between Drosophila sibling species: a complex web of epistasis is revealed in interspecific studies

    Microsoft Academic Search

    Michael F. Palopoli; Chung-I Wu

    1995-01-01

    To study the genetic differences responsible for the sterility of their male hybrids, we introgressed small segments of an X chromosome from Drosophila simulans into a pure Drosophila mauritiana genetic background, then assessed the fertility of males carrying heterospecific introgressions of varying size. Although this analysis examined less than 20% of the X chromosome (roughly 5% of the euchromatic portion

  10. Female swallow preference for symmetrical male sexual ornaments.

    PubMed

    Møller, A P

    1992-05-21

    Many secondary sexual characters are supposed to have evolved as a response to female choice of the most extravagantly ornamented males, a hypothesis supported by studies demonstrating female preferences for the most ornamented males. Comparative studies of elaborate feather ornaments in birds have shown that (1) ornaments have larger degrees of fluctuating asymmetry (small, random deviations from bilateral symmetry caused by an inability of individuals to cope with environmental and genetic stress during development of a character) than other morphological traits, and (2) the degree of fluctuating asymmetry is often negatively related to the size of the ornament. The negative relationship between ornament asymmetry and size suggests that ornament size reliably reflects male quality because the largest secondary sex traits demonstrate the least degree of fluctuating asymmetry. I manipulated tail length and tail asymmetry independently in male swallows (Hirundo rustica) to determine whether ornament size or asymmetry were used as cues in mate choice. Male swallows with elongated, symmetric tails mated earlier, and enjoyed larger annual reproductive success than did males with shortened tails and increased asymmetry. Females therefore prefer large as well as symmetric ornaments, which suggests that females in their mate choice use ornament asymmetry and size as reliable indicators of male quality. PMID:1589021

  11. Influence of methoprene and dietary protein on maturation and sexual performance of sterile, Anastrepha ludens (Diptera: Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Juvenile hormone levels and adult diet have important effects on the attractiveness and competitiveness of the male Anastrepha ludens (Loew) (Mexican fruit fly). Since the success of the sterile insect technique requires the release of males that can compete in the wild, these effects are very impor...

  12. Male-sterility induction in transgenic tobacco plants with an unedited atp9 mitochondrial gene from wheat.

    PubMed Central

    Hernould, M; Suharsono, S; Litvak, S; Araya, A; Mouras, A

    1993-01-01

    Cytoplasmic male sterility in plants is associated with mitochondrial dysfunction. We have proposed that a nuclear-encoded chimeric peptide formed by mitochondrial sequences when imported into the mitochondria may impair organelle function and induce male sterility in plants. A model developed to test this hypothesis is reported here. Assuming that the editing process in higher plant mitochondria reflects a requirement for producing active proteins, we have used edited and unedited coding sequences of wheat ATP synthase subunit 9 (atp9) fused to the coding sequence of a yeast coxIV transit peptide. Transgenic plants containing unedited atp9 exhibited either fertile, semifertile, or male-sterile phenotypes; controls containing edited atp9 or only the selectable marker gave fertile plants. Pollen fertility ranged from 31% to 75% in fertile plants, 10% to 20% in semifertile plants, and < 2% in male-sterile plants. Genetic and molecular data showed that the chimeric plasmid containing the transgene is inherited as a Mendelian trait. The transgenic protein is imported into the mitochondria. The production and frequency of semifertile or male-sterile transgenic plants conform to the proposed hypothesis. Images Fig. 2 Fig. 3 Fig. 4 PMID:7681593

  13. Expression of a pathogen-induced cysteine protease (AdCP) in tapetum results in male sterility in transgenic tobacco.

    PubMed

    Shukla, Pawan; Singh, Naveen Kumar; Kumar, Dilip; Vijayan, Sambasivam; Ahmed, Israr; Kirti, Pulugurtha Bharadwaja

    2014-06-01

    Usable male sterility systems have immense potential in developing hybrid varieties in crop plants, which can also be used as a biological safety containment to prevent horizontal transgene flow. Barnase-Barstar system developed earlier was the first approach to engineer male sterility in plants. In an analogous situation, we have evolved a system of inducing pollen abortion and male sterility in transgenic tobacco by expressing a plant gene coding for a protein with known developmental function in contrast to the Barnase-Barstar system, which deploys genes of prokaryotic origin, i.e., from Bacillus amyloliquefaciens. We have used a plant pathogen-induced gene, cysteine protease for inducing male sterility. This gene was identified in the wild peanut, Arachis diogoi differentially expressed when it was challenged with the late leaf spot pathogen, Phaeoisariopsis personata. Arachis diogoi cysteine protease (AdCP) was expressed under the strong tapetum-specific promoter (TA29) and tobacco transformants were generated. Morphological and histological analysis of AdCP transgenic plants showed ablated tapetum and complete pollen abortion in three transgenic lines. Furthermore, transcript analysis displayed the expression of cysteine protease in these male sterile lines and the expression of the protein was identified in western blot analysis using its polyclonal antibody raised in the rabbit system. PMID:24615687

  14. A low molecular weight proteome comparison of fertile and male sterile 8 anthers of Zea mays

    PubMed Central

    Wang, Dongxue; Adams, Christopher M.; Fernandes, John F.; Egger, Rachel L.; Walbot, Virginia

    2014-01-01

    Summary During maize anther development, somatic locular cells differentiate to support meiosis in the pollen mother cells. Meiosis is an important event during anther growth and is essential for plant fertility as pollen contains the haploid sperm. A subset of maize male sterile mutants exhibit meiotic failure, including ms8 (male sterile 8) in which meiocytes arrest as dyads and the locular somatic cells exhibit multiple defects. Systematic proteomic profiles were analysed in biological triplicates plus technical triplicates comparing ms8 anthers with fertile sibling samples at both the premeiotic and meiotic stages; proteins from 3.5 to 20 kDa were fractionated by 1-D PAGE, cleaved with Lys-C and then sequenced using a LTQ Orbitrap Velos MS paradigm. Three hundred and 59proteins were identified with two or more assigned peptides in which each of those peptides were counted at least two or more times (0.4% peptide false discovery rate (FDR) and 0.2% protein FDR); 2761 proteins were identified with one or more assigned peptides (0.4% peptide FDR and 7.6% protein FDR). Stage-specific protein expression provides candidate stage markers for early anther development, and proteins specifically expressed in fertile compared to sterile anthers provide important clues about the regulation of meiosis. 49% of the proteins detected by this study are new to an independent whole anther proteome, and many small proteins missed by automated maize genome annotation were validated; these outcomes indicate the value of focusing on low molecular weight proteins. The roles of distinctive expressed proteins and methods for mass spectrometry of low molecular weight proteins are discussed. PMID:22748129

  15. Molecular analysis of cytoplasmic male sterility in chives (Allium schoenoprasum L.).

    PubMed

    Potz, H; Tatlioglu, T

    1993-12-01

    The mitochondria of chive plants with normal N or male-sterile S cytoplasms have been examined by restriction fragment analysis and Southern hybridizations of mitochondrial DNA (mtDNA) and in organello protein biosynthesis. Restriction fragment patterns of the mtDNA differed extensively between N-and S-cytoplasms. The percentage of fragments with different mobility varied between 44-48% depending on the restriction enzyme used. In contrast to mtDNA, the restriction fragment patterns of the chloropolast DNA from N- and S-cytoplasms were identical. The organization of the analyzed mitochondrial genes coxII, coxIII, nad1 and nad3 was different in N- and S-cytoplasms. Comparison of mitochondrial proteins analyzed by in organello translation revealed an 18-kDa protein present only in S-cytoplasm. The restorer gene X suppressed the synthesis of that protein in S-cytoplasm. Thus, the 18-kDa protein seems to be associated with the cytoplasmic male-sterile phenotype. PMID:24190316

  16. The Arabidopsis male-sterile mutant, opr3, lacks the 12-oxophytodienoic acid reductase required for jasmonate synthesis

    Microsoft Academic Search

    Annick Stintzi; John Browse

    2000-01-01

    Jasmonic acid (JA) and its precursor 12-oxophytodienoic acid (OPDA) act as plant growth regulators and mediate responses to environmental cues. To investigate the role of these oxylipins in anther and pollen development, we characterized a T-DNA-tagged, male-sterile mutant of Arabidopsis, opr3. The opr3 mutant plants are sterile but can be rendered fertile by exogenous JA but not by OPDA. Cloning

  17. Genetic analyses supported by molecular methods provide evidence of a new genic (st1) and a new cytoplasmic (st2) male sterility in Allium schoenoprasum L

    Microsoft Academic Search

    T. Engelke; T. Tatlioglu

    2000-01-01

    Spontaneous mutations leading to male sterility have been described for many different crops and are of great importance to\\u000a hybrid breeding, provided that their inheritance is resolved. This paper describes an efficient method to characterise male\\u000a sterilities with respect to cytoplasmic factors that might be causally related to them. The differentiation of cytoplasmic\\u000a (CMS) and genic (GMS) male sterility is

  18. Alloplasmic male-sterile Brassica juncea with Enarthrocarpus lyratus cytoplasm and the introgression of gene(s) for fertility restoration from cytoplasm donor species

    Microsoft Academic Search

    S. S. Banga; J. S. Deol; S. K. Banga

    2003-01-01

    A new cytoplasmic male sterility (CMS) source in Brassica juncea (2n = 36; AABB) was developed by substituting its nucleus into the cytoplasm of Enarthrocarpus lyratus (2n = 20; EÊEÊ). Male sterility was complete, stable and manifested in either petaloid- or rudimentary-anthers which were devoid of fertile pollen grains. Male sterile plants resembled the euplasmic B. juncea except for slight

  19. Sexual isolation between Drosophila melanogaster females and Drosophila simulans males. I -Relation between

    E-print Network

    Paris-Sud XI, Université de

    Sexual isolation between Drosophila melanogaster females and Drosophila simulans males. I males were used. The dynamics of mating success as flies reached sexual maturity was examined. Female sexual maturity of the isofemale lines, estimated from mating frequency, gradually increased with ageing

  20. Sexual selection and variation in reproductive strategy in male yellow warblers ( Dendroica petechia )

    Microsoft Academic Search

    Michael V. Studd; Raleigh J. Robertson

    1985-01-01

    Male yellow warblers (Dendroica petechia) exhibit extensive variation in the amount and conspicuousness of the sexually distinctive brown streaking on the breast. We investigated this intraspecific variation in degree of sexual dichromatism to see if male plumage rank (essentially the amount of brown streaking) is correlated with the amount of reproductive effort allocated to parental investment, as sexual selection theory

  1. Theoretical Perspectives of Male Sexual Abuse: Conceptualization of a Case Study

    Microsoft Academic Search

    Terry Diamanduros; Clare E. Cosentino; P. Dawn Tysinger; Jeffrey A. Tysinger

    2012-01-01

    The purpose of this article is to demonstrate the traumatic impact that sexual abuse can have on a young male's development by addressing mediating dispositions that can render a child vulnerable to the effects of sexual abuse. Consideration is given to three different theoretical perspectives that are not exclusive to male victims but shed light on the impact that sexual

  2. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1.

    PubMed

    Zhu, Qidi; Song, Yulong; Zhang, Gaisheng; Ju, Lan; Zhang, Jiao; Yu, Yongang; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Wheat (Triticum aestivum L.), one of the world's most important food crops, is a strictly autogamous (self-pollinating) species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1-induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1-induced male sterile wheat and is a valuable source of data for future research in SQ-1-induced wheat male sterility. PMID:25898130

  3. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1

    PubMed Central

    Zhang, Gaisheng; Ju, Lan; Zhang, Jiao; Yu, Yongang; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-01-01

    Wheat (Triticum aestivum L.), one of the world’s most important food crops, is a strictly autogamous (self-pollinating) species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther transcriptomes for male fertile wheat and SQ-1–induced male sterile wheat was carried out using next-generation sequencing technology. In all, 42,634,123 sequence reads were generated and were assembled into 82,356 high-quality unigenes with an average length of 724 bp. Of these, 1,088 unigenes were significantly differentially expressed in the fertile and sterile wheat anthers, including 643 up-regulated unigenes and 445 down-regulated unigenes. The differentially expressed unigenes with functional annotations were mapped onto 60 pathways using the Kyoto Encyclopedia of Genes and Genomes database. They were mainly involved in coding for the components of ribosomes, photosynthesis, respiration, purine and pyrimidine metabolism, amino acid metabolism, glutathione metabolism, RNA transport and signal transduction, reactive oxygen species metabolism, mRNA surveillance pathways, protein processing in the endoplasmic reticulum, protein export, and ubiquitin-mediated proteolysis. This study is the first to provide a systematic overview comparing wheat anther transcriptomes of male fertile wheat with those of SQ-1–induced male sterile wheat and is a valuable source of data for future research in SQ-1–induced wheat male sterility. PMID:25898130

  4. Sexually selected behaviour: red squirrel males search for reproductive success.

    PubMed

    Lane, Jeffrey E; Boutin, Stan; Gunn, Melissa R; Coltman, David W

    2009-03-01

    1. Differential male reproductive success is commonplace in mammals and frequently attributed to variation in morphological traits that provide individuals with a competitive advantage in female defence mating systems. Other mammalian mating systems, however, have received comparatively little attention and correlates of male reproductive success in them are less well understood. 2. We studied a free-ranging population of North American red squirrels (Tamiasciurus hudsonicus Erxleben) exhibiting year-round individual territoriality. Males must temporarily vacate their territories to locate spatially dispersed receptive females, thereby setting the stage for a scramble competition mating system. 3. We predicted that both male annual mating success (measured as the number of females copulated with) and annual reproductive success (measured as the number of offspring sired) would be positively correlated with both search ability (measured as the number of oestrous females located over the mating season) and effort (measured as mating season home range size), generating directional sexual selection on these two metrics. 4. Mating season home ranges of males showed, on average, an almost 10-fold increase relative to those measured during the nonmating season, while those of females showed a more moderate twofold increase and both annual mating and reproductive success of males was positively correlated with search ability and search effort. 5. The spatial dispersion of females, resulting from the strict territorial social structure of red squirrels, gave rise to a predicted scramble competition mating system. Furthermore, the strength of sexual selection on behavioural traits in this mating system equalled previous estimates for morphological traits in female defence mating systems. PMID:19040682

  5. Knowledge of sexually transmitted diseases and sexual behaviours among Malaysian male youths.

    PubMed

    Awang, Halimah; Wong, Li Ping; Jani, Rohana; Low, Wah Yun

    2014-03-01

    This study examines the knowledge of sexually transmitted diseases (STDs) among male youths in Malaysia. A self-administered survey was carried out on a sample of 952 never-married males aged 15-24 years. The respondents were asked about their knowledge of STDs, how these diseases get transmitted and their sexual behaviours. The data showed that 92% of the respondents knew of at least one STD (syphilis, gonorrhoea, chlamydia, herpes, genital warts, yeast infection, trichomoniasis or HIV/AIDS). About 95% of them knew of at least one method of STD transmission. Urban and tertiary-educated male youths showed a substantially higher proportion of awareness of STDs and transmission methods compared with their rural and less-educated counterparts. The data also indicated that 10% of the study sample admitted to having had sexual experiences. There were still a large proportion of the respondents who were not aware of STDs other than syphilis and HIV/AIDS and the means of transmission, such as multiple sex partners, including those who claimed to be sexually active. Thus there is a need for more concerted efforts to disseminate information on STDs and transmission methods to a wider audience in Malaysia, especially youths in rural areas. PMID:23480474

  6. Exploring Family Factors and Sexual Behaviors in a Group of Black and Hispanic Adolescent Males.

    ERIC Educational Resources Information Center

    Rucibwa, Naphtal Kaberege; Modeste, Naomi; Montgomery, Susan; Fox, Curtis A.

    2003-01-01

    Examined family factors influencing sexual behavior among black and Hispanic adolescent males from San Bernardino County, California's 1996 Youth Survey. Family structure, parent sexual behaviors, and peer sexual norms closely associated with adolescent sexual attitudes and behaviors. Having a sibling who was a teen parent significantly associated…

  7. Cohabitation of juvenile females with mature males promotes sexual cannibalism in fishing spiders

    Microsoft Academic Search

    J. Chadwick Johnson

    2004-01-01

    Precopulatory sexual cannibalism, or female predation of a potential mate before mating, illustrates an extreme intersexual conflict. Unlike sexual cannibalism occurring after mating, precopulatory sexual cannibalism cannot be construed as a male strategy. Thus, research on the adaptive significance of this phenomenon has focused on female benefits. In the present study, I test the idea that precopulatory sexual cannibalism represents

  8. Approach to the male patient with sexual dysfunction.

    PubMed

    Lundberg, P O

    2015-01-01

    The management of the male patient with sexual dysfunction (SD) requires special knowledge and abilities. Generally, SD is best approached from the physiologic perspective, keeping in mind that sexual functioning has important psychosocial dimensions. The history obtained from the patient and, if possible, from his partner should seek information not only on the SD, but also on coexisting neurologic or medical disorders. A list of drugs should be obtained, as many prescription drugs, even in low doses, can influence sexual function. The clinical examination, including sensory, motor, and reflex testing of the lumbosacral segments, may reveal pertinent somatic abnormalities, which in the case of a suspected peripheral nervous system lesion may be supported by clinical neurophysiologic testing. The first-line diagnostic approach includes defining the type of sexual dysfunction to allow the most appropriate therapy. Metabolic and other systemic diseases need to be ruled out. Patients suspected of having psychologic, structural, urologic, endocrinologic, or vascular etiology of SD should be referred to the appropriate specialist. PMID:26003242

  9. Homosexual threat, negative attitudes toward masturbation, sex guilt, and males' sexual and affective reactions to explicit sexual films

    Microsoft Academic Search

    Donald L. Mosher; Kevin E. OGrady

    1979-01-01

    Subjective sexual arousal and affective responses of 215 undergraduate males to films of masturbatory, homosexual, and heterosexual behavior were studied as a function of personality differences in negative attitudes toward masturbation, homosexual threat, and sex guilt. The film of heterosexual behavior elicited more subjective sexual arousal and less disgust, anger, shame, depression, and guilt than did the films of male

  10. Genetic loss or pharmacological blockade of testes-expressed taste genes causes male sterility

    PubMed Central

    Mosinger, Bedrich; Redding, Kevin M.; Parker, M. Rockwell; Yevshayeva, Valeriya; Yee, Karen K.; Dyomina, Katerina; Li, Yan; Margolskee, Robert F.

    2013-01-01

    TAS1R taste receptors and their associated heterotrimeric G protein gustducin are involved in sugar and amino acid sensing in taste cells and in the gastrointestinal tract. They are also strongly expressed in testis and sperm, but their functions in these tissues were previously unknown. Using mouse models, we show that the genetic absence of both TAS1R3, a component of sweet and amino acid taste receptors, and the gustducin ?-subunit GNAT3 leads to male-specific sterility. To gain further insight into this effect, we generated a mouse model that expressed a humanized form of TAS1R3 susceptible to inhibition by the antilipid medication clofibrate. Sperm formation in animals without functional TAS1R3 and GNAT3 is compromised, with malformed and immotile sperm. Furthermore, clofibrate inhibition of humanized TAS1R3 in the genetic background of Tas1r3?/?, Gnat3?/? doubly null mice led to inducible male sterility. These results indicate a crucial role for these extraoral “taste” molecules in sperm development and maturation. We previously reported that blocking of human TAS1R3, but not mouse TAS1R3, can be achieved by common medications or chemicals in the environment. We hypothesize that even low levels of these compounds can lower sperm count and negatively affect human male fertility, which common mouse toxicology assays would not reveal. Conversely, we speculate that TAS1R3 and GNAT3 activators may help infertile men, particularly those that are affected by some of the mentioned inhibitors and/or are diagnosed with idiopathic infertility involving signaling pathway of these receptors. PMID:23818598

  11. Male sterility in Arabidopsis induced by overexpression of a MYC5-SRDX chimeric repressor.

    PubMed

    Figueroa, Pablo; Browse, John

    2015-03-01

    Jasmonate hormone (JA) plays critical roles in both plant defense and reproductive development. Arabidopsis thaliana plants deficient in JA-biosynthesis or -signaling are male-sterile, with defects in stamen and pollen development. MYC2, MYC3 and MYC4 are JAZ-interacting bHLH transcription factors that play a major role in controlling JA responses in vegetative tissue, but are not likely to play a role in reproductive tissue. We found that a closely related transcription factor, MYC5 (bHLH28), was able to induce JAZ promoters that control some of the early JA-responsive genes in a Daucus carota (carrot) protoplast expression system. A G-box sequence in the JAZ2 promoter was necessary and sufficient for induction by MYC5 (as it is for MYC2, MYC3 and MYC4), and induction of JAZ genes was repressed by co-expression of a stabilized, JAZ1?Jas repressor. Two allelic myc5 mutants exhibited no overt phenotype; however, transgenic lines expressing MYC5 fused to an SRDX (SUPERMAN repressive domain X) motif phenocopied mutants defective in JA signaling. In particular, MYC5-SRDX plants were male-sterile, with defects in stamen filament elongation, anther dehiscence and pollen viability. Importantly, expression of MYB21 and other transcription factors required for stamen and pollen maturation was strongly reduced in stamens of MYC5-SRDX plants relative to the wild type. Taken together, these results indicate that MYC5, probably together with other, redundant transcription factors, may be activated by JA signaling to induce the expression of MYB21 and components required for male fertility. PMID:25627909

  12. A long noncoding RNA regulates photoperiod-sensitive male sterility, an essential component of hybrid rice

    PubMed Central

    Ding, Jihua; Lu, Qing; Ouyang, Yidan; Mao, Hailiang; Zhang, Pingbo; Yao, Jialing; Xu, Caiguo; Li, Xianghua; Xiao, Jinghua; Zhang, Qifa

    2012-01-01

    Hybrid rice has greatly contributed to the global increase of rice productivity. A major component that facilitated the development of hybrids was a mutant showing photoperiod-sensitive male sterility (PSMS) with its fertility regulated by day length. Transcriptome studies have shown that large portions of the eukaryotic genomic sequences are transcribed to long noncoding RNAs (lncRNAs). However, the potential roles for only a few lncRNAs have been brought to light at present. Thus, great efforts have to be invested to understand the biological functions of lncRNAs. Here we show that a lncRNA of 1,236 bases in length, referred to as long-day–specific male-fertility–associated RNA (LDMAR), regulates PSMS in rice. We found that sufficient amount of the LDMAR transcript is required for normal pollen development of plants grown under long-day conditions. A spontaneous mutation causing a single nucleotide polymorphism (SNP) between the wild-type and mutant altered the secondary structure of LDMAR. This change brought about increased methylation in the putative promoter region of LDMAR, which reduced the transcription of LDMAR specifically under long-day conditions, resulting in premature programmed cell death (PCD) in developing anthers, thus causing PSMS. Thus, a lncRNA could directly exert a major effect on a trait like a structure gene, and a SNP could alter the function of a lncRNA similar to amino acid substitution in structural genes. Molecular elucidating of PSMS has important implications for understanding molecular mechanisms of photoperiod regulation of many biological processes and also for developing male sterile germplasms for hybrid crop breeding. PMID:22308482

  13. Causes of male sexual trait divergence in introduced populations of guppies

    PubMed Central

    Lindholm, A K; Head, M L; Brooks, R C; Rollins, L A; Ingleby, F C; Zajitschek, S R K

    2014-01-01

    Males from different populations of the same species often differ in their sexually selected traits. Variation in sexually selected traits can be attributed to sexual selection if phenotypic divergence matches the direction of sexual selection gradients among populations. However, phenotypic divergence of sexually selected traits may also be influenced by other factors, such as natural selection and genetic constraints. Here, we document differences in male sexual traits among six introduced Australian populations of guppies and untangle the forces driving divergence in these sexually selected traits. Using an experimental approach, we found that male size, area of orange coloration, number of sperm per ejaculate and linear sexual selection gradients for male traits differed among populations. Within populations, a large mismatch between the direction of selection and male traits suggests that constraints may be important in preventing male traits from evolving in the direction of selection. Among populations, however, variation in sexual selection explained more than half of the differences in trait variation, suggesting that, despite within-population constraints, sexual selection has contributed to population divergence of male traits. Differences in sexual traits were also associated with predation risk and neutral genetic distance. Our study highlights the importance of sexual selection in trait divergence in introduced populations, despite the presence of constraining factors such as predation risk and evolutionary history. PMID:24456226

  14. Childhood experiences of incarcerated male child sexual abusers.

    PubMed

    Garrett, Linda H

    2010-10-01

    While numerous efforts have been made to understand the impact of child sexual abuse, little has been done to examine the childhood experiences of those who abuse children. Child sexual abusers have been studied from quantitative perspectives using behavioral checklists, parental-bonding surveys, and sexual history questionnaires. The purpose of this study was to explore incarcerated child sexual abusers' recollections of their childhood experiences using the descriptive existential lens of phenomenology. Eight incarcerated male child sexual abusers described their childhood from existential perspectives of lived space, lived other, lived body, and lived time via face-to-face semi-structured interviews. Analysis was accomplished through the qualitative, descriptive method of Max van Manen. Rich descriptions of the participants' insights into their daily childhood life experiences that shaped their self-concepts and contributed to their adult behaviors were gathered. Four major themes were identified: (1) failure to root, (2) what you see is what you learn, (3) stupid is as stupid does, and (4) life's moments. Data from this study suggest that the experiences of childhood significantly contribute to an adult self-concept that can be distorted by the lack of a secure home space, maladaptive relationships, internalization of inappropriate behavior, and a lack of significant family development. This study explores the psychosocial and behavioral consequences of early childhood experiences. The findings support the need for family and psychological mental health nurse practitioners to be more aware of early home environments; improve their assessment of children's developing self-concept and the potential for abusive relationships. PMID:20854041

  15. Sexual Selection, Ontogenetic Acceleration, and Hypermorphosis Generates Male Trimorphism in Wellington Tree Weta

    Microsoft Academic Search

    Clint D. KellyDean

    2010-01-01

    Strong sex-specific selection on traits common to both sexes typically results in sexual dimorphism. Here we find that Wellington tree weta (Hemideina crassidens) are sexually dimorphic in both head shape and size due to differential selection pressures on the sexes: males use their heads in male-male combat and feeding whereas females use theirs for feeding only. Remarkably, the sexes share

  16. Drugs For Male Sexual Dysfunction Show Promise In The Lab For Treating Female Sexual Disorders

    NSDL National Science Digital Library

    APS Communications Office (American Physiological Society Communications Office)

    2006-04-17

    This is an APS press release on a study that found that female sexual dysfunction may be, in part, the result of inadequate supply of blood to the female genitals and may be addressed with erectile dysfunction drugs. Originally developed as therapy for hypertension, these drugs work by dilating blood vessels sufficiently to produce erections in males. These drugs have not been fully explored in females.

  17. Cytochemical Analysis of Pollen Development in Wild-Type Arabidopsis and a Male-Sterile Mutant.

    PubMed Central

    Regan, SM; Moffatt, BA

    1990-01-01

    Microsporogenesis has been examined in wild-type Arabidopsis thaliana and the nuclear male-sterile mutant BM3 by cytochemical staining. The mutant lacks adenine phosphoribosyltransferase, an enzyme of the purine salvage pathway that converts adenine to AMP. Pollen development in the mutant began to diverge from wild type just after meiosis, as the tetrads of microspores were released from their callose walls. The first indication of abnormal pollen development in the mutant was a darker staining of the microspore wall due to an incomplete synthesis of the intine. Vacuole formation was delayed and irregular in the mutant, and the majority of the mutant microspores failed to undergo mitotic divisions. Enzyme activities of alcohol dehydrogenase and esterases decreased in the mutant soon after meiosis and were undetectable in mature pollen grains of the mutant. RNA accumulation was also diminished. These results are discussed in relation to the possible role(s) of adenine salvage in pollen development. PMID:12354970

  18. Behavioral sterility of hybrid males in acoustically communicating grasshoppers (Acrididae, Gomphocerinae).

    PubMed

    Gottsberger, Brigitte; Mayer, Frieder

    2007-07-01

    The effectiveness of hybridization barriers determines whether two species remain reproductively isolated when their populations come into contact. We investigated acoustic mating signals and associated leg movements responsible for song creation of hybrids between the grasshopper species Chorthippus biguttulus and C. brunneus to study whether and how songs of male hybrids contribute to reproductive isolation between these sympatrically occurring species. Songs of F1, F2, and backcross hybrids were intermediate between those of both parental species in terms phrase number and duration. In contrast, species-specific syllable structure within phrases was largely lost in hybrids and was produced, if at all, in an irregular and imperfect manner. These divergences in inheritance of different song parameters are likely the result of incompatibility of neuronal networks that control stridulatory leg movements in hybrids. It is highly probable that songs of hybrid males are unattractive to females of either parental species because they are intermediate in terms of phrase duration and lack a clear syllable structure. Males of various hybrid types (F1, F2, and backcrosses) are behaviorally sterile because their songs fail to attract mates. PMID:17440734

  19. Risky sexual behavior among women with protective orders against violent male partners

    Microsoft Academic Search

    Jennifer Cole; T. K. Logan; Lisa Shannon

    2007-01-01

    The purpose of this study was to describe risky sexual behaviors among women with protective orders against violent male partners\\u000a (N=673), as well as to examine associations of relationship factors, psychological abuse, severity of partner violence, sexual\\u000a violence, and women’s substance abuse with risky sexual behavior. An HIV sexual risk index was computed based on the participant’s\\u000a self-reported risky sexual

  20. Location of X-linked polygenic effects causing sterility in male hybrids of Drosophila simulans and D. mauritiana.

    PubMed

    Naveira, H F

    1992-03-01

    There is general agreement that hybrid male sterility in Drosophila is caused by changes at several (perhaps many) factors, most of them located on the X chromosome. These factors have been generally considered as major genes, each one of them able to bring about sterility by itself. However, the evidence on this last point is not conclusive. In principle, the possibility that they correspond to located polygenic effects instead of genes with a large effect cannot be excluded. This paper shows that some of the factors that cause male sterility in D. simulans/D. mauritiana hybrids, located by recombination on the X chromosome, are indeed 'effective factors', or located polygenic effects. Some of the consequences of this finding are explored. PMID:1559838

  1. Subunit 6 of the Fo-ATP synthase complex from cytoplasmic male-sterile radish: RNA editing and NH2-terminal protein sequencing

    Microsoft Academic Search

    Subbiah Krishnasamy; Raymond A. Grant; Christopher A. Makaroff

    1994-01-01

    RNA editing and NH2-terminal processing of subunit 6 (atp6) of the mitochondrial Fo-ATPase complex has been investigated for the normal (fertile) and Ogura (male-sterile) radish cytoplasms to determine if previously identified differences between the Ogura atp6 locus and its normal radish counterpart are associated with cytoplasmic male sterility. Analysis of cDNA clones from five different sterile and fertile radish lines

  2. Morphological and Cytological Study in a New Type of Cytoplasmic Male Sterile Line CMS-GIG2 in Sunflower (Helianthus annuus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new cytoplasmic male sterility (CMS) in sunflower anthers, termed lemon CMS-GIG2, has been further confirmed by crossing with the maintenance line and restoration line of CMS-PET1, both of which maintain the male sterility of CMS-GIG2. Light microscopy observation of anther sections showed that bo...

  3. Identification of RAPD markers linked to a fertility restorer gene for the Ogura radish cytoplasmic male sterility of rapeseed ( Brassica napus L.)

    Microsoft Academic Search

    R. Delourme; A. Bouchereau; N. Hubert; M. Renard; B. S. Landry

    1994-01-01

    Bulked segregant analysis was employed to identify random amplified polymorphic DNA (RAPD) markers linked to the restorer gene (Rfo) used in theOgura radish cytoplasmic male sterility of rapeseed. A total of 138 arbitrary 10-mer oligonucleotide primers were screened on the DNA of three pairs of bulks, each bulk corresponding to homozygous restored and male sterile plants of three segregating populations.

  4. Registration of N614, A3N615, N616, and N617 Shattercane Genetic Stocks with cytoplasmic or nuclear male-sterility and juicy or dry midribs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four shattercane [Sorghum bicolor subsp. drummondii (Nees ex Steud) de Wet & Harlan] genetic stocks, N614, A3N615, N616, N617 (Reg. No. XXX, PI 665683 to 665686), with A3 cytoplasmic male-sterility or nuclear male-sterility gene ms3 containing either juicy (dd) or dry (DD) culms were developed joint...

  5. Assembly and analysis of a male sterile rubber tree mitochondrial genome reveals DNA rearrangement events and a novel transcript

    PubMed Central

    2014-01-01

    Background The rubber tree, Hevea brasiliensis, is an important plant species that is commercially grown to produce latex rubber in many countries. The rubber tree variety BPM 24 exhibits cytoplasmic male sterility, inherited from the variety GT 1. Results We constructed the rubber tree mitochondrial genome of a cytoplasmic male sterile variety, BPM 24, using 454 sequencing, including 8 kb paired-end libraries, plus Illumina paired-end sequencing. We annotated this mitochondrial genome with the aid of Illumina RNA-seq data and performed comparative analysis. We then compared the sequence of BPM 24 to the contigs of the published rubber tree, variety RRIM 600, and identified a rearrangement that is unique to BPM 24 resulting in a novel transcript containing a portion of atp9. Conclusions The novel transcript is consistent with changes that cause cytoplasmic male sterility through a slight reduction to ATP production efficiency. The exhaustive nature of the search rules out alternative causes and supports previous findings of novel transcripts causing cytoplasmic male sterility. PMID:24512148

  6. Genetic analysis and molecular mapping of an Rf gene from Helianthus angustifolius for a new cytoplasmic male-sterile line

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The combination of cytoplasmic male-sterile (CMS) and the corresponding fertility restoration genes (Rf) is a critical tool in large-scale hybrid seed production of sunflower. A new CMS line 514A, derived from H. tuberosus / 7718B, was obtained from a scientific exchange with the Liaoning Academy of...

  7. Mutations at specific atp6 codons which cause human mitochondrial diseases also lead to male sterility in a plant

    Microsoft Academic Search

    Frank Kempken; Werner Howad; Daryl R. Pring

    1998-01-01

    Defects in the human mitochondrial genetic system result in some diseases. These disorders are the result of rearrangements or point mutations in mitochondrial genes. In higher plants mutations and rearrangements in the mitochondrial DNA are believed to cause cytoplasmic male sterility (CMS), a mitochondrially inherited inability to produce viable pollen. In sorghum, formation of CMS is strongly correlated with anther-specific

  8. Interspecific amphiploid-derived alloplasmic male sterility with defective anthers, narrow disk florets, and small ray flowers in sunflower

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cytoplasmic male-sterility (CMS)/fertility-restoration system is important for hybrid sunflower (Helianthus annuus L.) seed production. Two novel alloplasmic CMSs, designated CMS GRO1 and CMS MAX3 with defective anthers, narrow disk florets with no swollen corolla, and short, narrow ray flowers,...

  9. Physical and gene mapping of chloroplast DNA from normal and cytoplasmic male sterile (radish cytoplasm) lines of Brassica napus

    Microsoft Academic Search

    Fernand Vedel; Chantal Mathieu

    1983-01-01

    Using the restriction endonucleases SaII, SmaI, BgII and KpnI, physical maps of chloroplast DNA isolated from normal and cytoplasmic male sterile (radish cytoplasm) lines of B. napus were constructed and compared. In this study, a rapid and simple procedure was developed for the isolation of chloroplast DNA restriction fragments from low gelling temperature agarose gels.

  10. Fertility restoration of the sorghum A3 male-sterile cytoplasm through a sporophytic mechanism derived from sudangrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fertility restoration of sorghum lines carrying the IS1112C (A3 group) sorghum male-sterile cytoplasm in the line A3Tx398 has been documented as a two-gene gametophytic mechanism involving complementary action of restoring alleles designated Rf3 and Rf4, as derived from IS1112C. Fertility restorat...

  11. A cytoplasmic-nuclear male-sterility system derived from a cross between Cajanus cajanifolius and Cajanus cajan

    Microsoft Academic Search

    K. B. Saxena; R. V. Kumar; Namita Srivastava; Bao Shiying

    2005-01-01

    Cytoplasmic-nuclear male-sterility is an important biological tool, which has been used by plant breeders to increase yields\\u000a in cross-pollinated cereals and vegetables by commercial exploitation of the phenomenon of hybrid vigor. In legumes, no such\\u000a example exists due to the absence of an economic way of mass pollen transfer from male to female parent. Pigeonpea [Cajanus cajan (L.) Millsp.], however,

  12. Heterosexual Male Perpetrators of Childhood Sexual Abuse: A Preliminary Neuropsychiatric Model

    Microsoft Academic Search

    Lisa J. Cohen; Konstantin Nikiforov; Sniezyna Gans; Olga Poznansky; Pamela McGeoch; Carrie Weaver; Enid Gertmanian King; Ken Cullen; Igor Galynker

    2002-01-01

    This paper presents data from a series of prelimary neuropsychiatric studies, including neuropsychological, personality, sexual history, plethysmographic and neuroimaging investigations, on a sample of 22 male, heterosexual, nonexclusive pedophiles and 24 demographically similar healthy controls. A psychobiological model of pedophilia is proposed, positing that early childhood sexual abuse leads to neurodevelopmental abnormalities in the temporal regions mediating sexual arousal and

  13. Are Males and Females Sexually Abused as Children Socially Anxious Adults?

    ERIC Educational Resources Information Center

    Rojas, Ariz; Kinder, Bill N.

    2009-01-01

    It is well documented that childhood sexual abuse is associated with deleterious outcomes in the areas of anxiety, depression, and sexual functioning. However, very little research has been conducted to specifically investigate childhood sexual abuse's relationship to adult social anxiety in both males and females. Participants included 250…

  14. The dual control model of male sexual response: a theoretical approach to centrally mediated erectile dysfunction

    E-print Network

    preoccupation with sexual rewards); 4. Where sexual and reproductive behavior is inhibited by chronic stressThe dual control model of male sexual response: a theoretical approach to centrally mediated and Reproduction, Morrison Hall 313, Indiana University, 1165 East Third Street, Bloomington, IN 47405-3700, USA

  15. Sexual Assault on the College Campus: The Role of Male Peer Support.

    ERIC Educational Resources Information Center

    Schwartz, Martin D.; DeKeseredy, Walter S.

    This book links research on two topics--sexual assault on North American college and university campuses and the role played by male peer support in such assaults. Disputing the notion that college campuses are safe havens from crime, the first chapter defines sexual assault, notes the incidence and prevalence of campus sexual assault, and…

  16. Female sexual swelling size, timing of ovulation, and male behavior in wild West African chimpanzees

    E-print Network

    ) direct size measures (from video captures) of female sexual swellings with (ii) urinary hormone dataFemale sexual swelling size, timing of ovulation, and male behavior in wild West African'' hypothesis that take into account not only the pattern but also the exaggerated size of sexual swellings

  17. Childhood abuse and premilitary sexual assault in male Navy recruits.

    PubMed

    Merrill, L L; Thomsen, C J; Gold, S R; Milner, J S

    2001-04-01

    Three samples of male U.S. Navy recruits (N = 7,850) were surveyed to determine whether a history of childhood physical abuse (CPA) or childhood sexual abuse (CSA) was predictive of premilitary rape of women and whether these relationships were mediated by alcohol problems and number of sex partners. In the 3 samples, 11.3%, 11.6%, and 9.9% of men reported committing premilitary rape. When demographic factors were controlled for, both CPA and CSA were independently and additively predictive of rape in each sample, with men who experienced both forms of abuse showing the highest risk of committing rape. Additional analyses revealed that alcohol problems and number of sex partners significantly mediated the relationship between childhood abuse (CPA and CSA) and rape perpetration. PMID:11393602

  18. Personal and Perceived Peer Attitudes Supporting Sexual Aggression as Predictors of Male College Students' Willingness to Intervene against Sexual Aggression

    ERIC Educational Resources Information Center

    Brown, Amy L.; Messman-Moore, Terri L.

    2010-01-01

    Male college students (N = 395) completed anonymous surveys to report personal attitudes supporting sexual aggression and estimated the attitudes of their peers. Participants also indicated their willingness to intervene against a peer if they witnessed sexual aggression. Although both personal and peer attitudes were correlated with willingness…

  19. Functional assessment of sexual maturity in male macaques (Macaca fascicularis).

    PubMed

    Luetjens, C M; Weinbauer, G F

    2012-08-01

    Selection of suitable criteria for assessing sexual maturity in the male long-tailed macaque (Macaca fascicularis) has yielded conflicting results. The present retrospective work investigates whether the sole presence of sperm in the baseline semen sample unequivocally (i.e. for every animal) hallmarks complete testicular maturation. For 956 animals providing the baseline semen sample, neither age, body weight nor testes volume unequivocally predicted the presence of sperm in that sample, and for 322 animals these parameters failed to predict testicular histology. In contrast, the presence of sperm in the baseline semen sample correlated with mature testis histology at study termination in every single animal (n=197/322). Surprisingly, for the 125/322 animals without sperm in the baseline semen sample, spermatogenesis was also mature in 95 animals. Thus, the mere provision of a semen sample without sperm--implying peripheral reproductive tract maturation--was associated with mature spermatogenesis in approx. 75% of animals. Interestingly, testicular maturation occurred approx. 2 years earlier in Mauritian compared to Asian mainland animals. In conclusion, a single semen sample that contains sperm provides unequivocal evidence for mature spermatogenesis and, thus, is suggested as a functional parameter for sexual maturity assessment in this species. PMID:22579626

  20. Effects of Chronic Hyperprolactinemia on Sexual Arousal and Erectile Function in Male Rats

    Microsoft Academic Search

    Paul C. Doherty; Michael J. Baum; Roberta B. Todd

    1986-01-01

    Studies were conducted to determine if the inhibitory effects of chronic hyperprolactinemia on sexual behavior in male rats occur through reduced sexual arousal as opposed to reduced erectile function. Pituitary-grafted (hyperprolactinemic) and sham-operated, gonadally intact male rats were given standard tests of copulatory behavior, mounting behavior tests after genital anesthetization and penile reflex tests while restrained in a supine position.

  1. Sex workers' noncommercial male partners who inject drugs report higher-risk sexual behaviors.

    PubMed

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

    2013-10-01

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

  2. I Keep That Hush-Hush: Male Survivors of Sexual Abuse and the Challenges of Disclosure

    Microsoft Academic Search

    Lynn Sorsoli; Maryam Kia-Keating; Frances K. Grossman

    2008-01-01

    Disclosure is a prominent variable in child sexual abuse research, but little research has examined male disclosure experiences. Sixteen male survivors of childhood sexual abuse were interviewed regarding experiences of disclosure. Analytic techniques included a grounded theory approach to coding and the use of conceptually clustered matrices. Participants described distinct personal (e.g., lack of cognitive awareness, intentional avoidance, emotional readiness,

  3. "I Keep That Hush-Hush": Male Survivors of Sexual Abuse and the Challenges of Disclosure

    ERIC Educational Resources Information Center

    Sorsoli, Lynn; Kia-Keating, Maryam; Grossman, Frances K.

    2008-01-01

    Disclosure is a prominent variable in child sexual abuse research, but little research has examined male disclosure experiences. Sixteen male survivors of childhood sexual abuse were interviewed regarding experiences of disclosure. Analytic techniques included a grounded theory approach to coding and the use of conceptually clustered matrices.…

  4. Male and female differences in reaction to erotic stimuli as related to sexual adjustment

    Microsoft Academic Search

    Daniel G. Steele; C. Eugene Walker

    1974-01-01

    One hundred male and 100 female undergraduate students viewed erotic slides depicting a wide range of human sexual behaviors. Each subject rated the stimuli on three criteria: sexual stimulation, liking for the slide, and extremeness of the behavior portrayed. Following the rating session, subjects completed Thorne's Sex Inventory, which theoretically measures psychosexual adjustment. Results indicated that males and females reported

  5. Vulnerable Sexuality and HIV/AIDS Prevention Knowledge among Ethnic Tribal Male Youth in Bangladesh

    ERIC Educational Resources Information Center

    Kamal, S. M. Mostafa

    2012-01-01

    This study examines sexuality and HIV/AIDS prevention knowledge among minority ethnic male youth of Bangladesh. A cross-sectional survey was conducted through a self-administered questionnaire on 800 young males aged 15-24 years in the Chittagong Hill Tracts region in 2009. Of the respondents, almost one-third were sexually active and of them…

  6. Genetic Variation in Male and Female Reproductive Characters Associated with Sexual Conflict in Drosophila melanogaster

    Microsoft Academic Search

    Urban Friberg

    2005-01-01

    Recent studies have shown that elevated mating, courtship and seminal substances affect female fitness negatively in Drosophila melanogaster. It has also been shown that males vary with respect to these characters and that male harm to females correlates positively with components of male fitness. These results suggest that there is sexual conflict over the effect of such male characters. An

  7. Male sexual behaviour and ethanol consumption from an evolutionary perspective: A comment on "Sexual Deprivation Increases Ethanol Intake in Drosophila".

    PubMed

    Guevara-Fiore, Palestina; Endler, John A

    2014-10-01

    Shohat-Ophir et al. (1) demonstrate a connection between sexual behaviour and ethanol consumption in male Drosophila flies, and how the neuropeptide F system regulates ethanol preference. Their results are rightly discussed only in a physiological context, but this has facilitated erroneous anthropomorphic interpretations by the media. Here we discuss the link between male sexual behaviour and ethanol consumption from an evolutionary perspective, providing a broader context to interpret their results. PMID:25970263

  8. Attachment and personality predicts engagement in sexual harassment by male and female college students.

    PubMed

    Mènard, Kim S; Shoss, Naomi E; Pincus, Aaron L

    2010-01-01

    The purpose of this study was to examine a trait model of personality (Five-Factor Model) as a mediator of the relationship between attachment styles and sexually harassing behavior in a sample of male (N = 148) and female (N = 278) college students. We found that gender (male) and low Agreeableness predicted engaging in sexual harassment and all three of its subtypes; gender harassment, unwanted sexual attention, and sexual coercion. Further, low Conscientiousness predicted overall sexual harassment, gender harassment, and unwanted sexual attention. Personality traits mediated the relationship between insecure attachment styles (Preoccupation with Relationships and Relationships as Secondary) and sexually harassing behaviors. Thus, factors beyond gender can help predict students' propensity to sexually harass others. PMID:21287966

  9. Transgenic male-sterile plant induced by an unedited atp9 gene is restored to fertility by inhibiting its expression with antisense RNA.

    PubMed Central

    Zabaleta, E; Mouras, A; Hernould, M; Suharsono; Araya, A

    1996-01-01

    We have previously shown that the expression of an unedited atp9 chimeric gene correlated with male-sterile phenotype in transgenic tobacco plant. To study the relationship between the expression of chimeric gene and the male-sterile trait, hemizygous and homozygous transgenic tobacco lines expressing the antisense atp9 RNA were constructed. The antisense producing plants were crossed with a homozygous male-sterile line, and the F1 progeny was analyzed. The offspring from crosses between homozygous lines produced only male-fertile plants, suggesting that the expression antisense atp9 RNA abolishes the effect of the unedited chimeric gene. In fact, the plants restored to male fertility showed a dramatic reduction of the unedited atp9 transcript levels, resulting in normal flower development and seed production. These results support our previous observation that the expression of unedited atp9 gene can induce male sterility. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8855343

  10. Sexual behavior and AIDS knowledge of young male prostitutes in Manhattan

    Microsoft Academic Search

    Richard R. Pleak

    1990-01-01

    Despite their presumed high risk for AIDS, there are almost no sexual behavior data available which are sufficient for the development and assessment of intervention programs for male prostitutes. This study was designed to obtain such data. Fifty 14–27?year?old male prostitutes in Manhattan were interviewed using structured instruments to assess sexual orientation, sexual behavior, knowledge of AIDS, and substance abuse.

  11. Measurement of Sexual Arousal in Postoperative Male-to-Female Transsexuals Using Vaginal Photoplethysmography

    Microsoft Academic Search

    Anne A. Lawrence; Elizabeth M. Latty; Meredith L. Chivers; J. Michael Bailey

    2005-01-01

    Mens sexual arousal patterns are category-specific: Men typically display significantly greater physiological responses to sexual stimuli depicting members of their preferred gender category. Category-specific patterns of sexual arousal have not been consistently reported in natal women. We used vaginal photoplethysmography to examine patterns of sexual arousal in 11 male-to-female (MtF) transsexuals following sex reassignment surgery (SRS) and in 72 natal

  12. Sexual Behavior in High-Functioning Male Adolescents and Young Adults with Autism Spectrum Disorder

    Microsoft Academic Search

    Hans Hellemans; Kathy Colson; Christine Verbraeken; Robert Vermeiren; Dirk Deboutte

    2007-01-01

    Group home caregivers of 24 institutionalized, male, high-functioning adolescents and young adults with Autism Spectrum Disorder,\\u000a were interviewed with the Interview Sexuality Autism. Most subjects were reported to express sexual interest and to display\\u000a some kind of sexual behavior. Knowledge of socio-sexual skills existed, but practical use was moderate. Masturbation was common.\\u000a Many subjects were seeking physical contact with others.

  13. Postcopulatory Sexual Selection and the Evolution of Male Pregnancy in the Gulf Pipefish 

    E-print Network

    Paczolt, Kimberly

    2012-07-16

    . As in precopulatory sexual selection, postcopulatory sexual selection can occur as the result of interactions within a sex, usually as sperm competition (Parker 1970), or between sexes, usually as cryptic female choice (Eberhard 1996). Sperm competition includes... to offspring from a preferred mate (Burley 1988, Sheldon 2000). Previous studies in postcopulatory sexual selection have focused on species with traditional sex roles, where males compete for access to females. By studying postcopulatory sexual selection...

  14. Fusion-mediated combination of Ogura-type cytoplasmic male sterility with Brassica napus plastids using X-irradiated CMS protoplasts

    Microsoft Academic Search

    Laszlo Menczel; Alison Morgan; Stacey Brown; Pal Maliga

    1987-01-01

    X-irradiated protoplasts of a Brassica napus line carrying the Ogura Raphanus sativus male sterile cytoplasm were fused to protoplasts of male fertile B. napus cv. Olga. Plants were regenerated from six out of 34 randomly selected clones. In one clone, Bn(RS)26, a plant with male sterile flowers was obtained. Mitochondria of this plant are non-parental as revealed by DNA-DNA hybridization

  15. The role of sexually explicit material in the sexual development of same-sex-attracted Black adolescent males.

    PubMed

    Arrington-Sanders, Renata; Harper, Gary W; Morgan, Anthony; Ogunbajo, Adedotun; Trent, Maria; Fortenberry, J Dennis

    2015-04-01

    Sexually explicit material (SEM) (including Internet, video, and print) may play a key role in the lives of Black same-sex sexually active youth by providing the only information to learn about sexual development. There is limited school- and/or family-based sex education to serve as models for sexual behaviors for Black youth. We describe the role SEM plays in the sexual development of a sample of Black same-sex attracted (SSA) young adolescent males ages 15-19. Adolescents recruited from clinics, social networking sites, and through snowball sampling were invited to participate in a 90-min, semi-structured qualitative interview. Most participants described using SEM prior to their first same-sex sexual experience. Participants described using SEM primarily for sexual development, including learning about sexual organs and function, the mechanics of same-gender sex, and to negotiate one's sexual identity. Secondary functions were to determine readiness for sex; to learn about sexual performance, including understanding sexual roles and responsibilities (e.g., "top" or "bottom"); to introduce sexual performance scripts; and to develop models for how sex should feel (e.g., pleasure and pain). Youth also described engaging in sexual behaviors (including condom non-use and/or swallowing ejaculate) that were modeled on SEM. Comprehensive sexuality education programs should be designed to address the unmet needs of young, Black SSA men, with explicit focus on sexual roles and behaviors that may be inaccurately portrayed and/or involve sexual risk-taking (such as unprotected anal intercourse and swallowing ejaculate) in SEM. This work also calls for development of Internet-based HIV/STI prevention strategies targeting young Black SSA men who may be accessing SEM. PMID:25677334

  16. Rethinking sexual initiation: pathways to identity formation among gay and bisexual Mexican male youth.

    PubMed

    Carrillo, Héctor; Fontdevila, Jorge

    2011-12-01

    The topic of same-sex sexual initiation has generally remained understudied in the literature on sexual identity formation among sexual minority youth. This article analyzes the narratives of same-sex sexual initiation provided by 76 gay and bisexual Mexican immigrant men who participated in interviews for the Trayectos Study, an ethnographic study of sexuality and HIV risk. These participants were raised in a variety of locations throughout Mexico, where they also realized their same-sex attraction and initiated their sexual lives with men. We argue that Mexican male same-sex sexuality is characterized by three distinct patterns of sexual initiation--one heavily-based on gender roles, one based on homosociality, and one based on object choice--which inform the men's interpretations regarding sexual roles, partner preferences, and sexual behaviors. We analyzed the social factors and forms of cultural/sexual socialization that lead sexual minority youth specifically to each of these three patterns of sexual initiation. Our findings confirm the importance of studying same-sex sexual initiation as a topic in its own right, particularly as a tool to gain a greater understanding of the diversity of same-sex sexual experiences and sexual identities within and among ethnic/cultural groups. PMID:20838869

  17. Dispersal and survival of Aedes albopictus (Diptera: Culicidae) males in Italian urban areas and significance for sterile insect technique application.

    PubMed

    Bellini, Romeo; Albieri, Alessandro; Balestrino, Fabrizio; Carrieri, Marco; Porretta, Daniele; Urbanelli, Sandra; Calvitti, Maurizio; Moretti, Riccardo; Maini, Stefano

    2010-11-01

    The dispersal and survival of laboratory-reared Aedes albopictus Skuse males were investigated during the summer of 2007 in three Northern Italy urban localities by mark-release-recapture techniques. Two marking methods were compared: one group of males was dusted with fluorescent pigments on the body (FP), and the other group was obtained from a strain whose natural infection of Wolbachia had been removed (WB0). FP- and WB0-marked males were released as adults and pupae, respectively, in one fixed station at each locality. Recaptures were performed by skilled technicians, within a radius of 350 m from the release site, on days 4, 5, and 7 after the release, and the males were collected while flying around the technician's body or in swarms. Recapture rates ranged from 0.63 to 4.72% for FP males and from 2.39 to 11.05% for WB0 males. The mean distance traveled for WB0 males was significantly higher than for FP males; no difference was observed between the dispersal distance measured for the males recaptured on human host versus males recaptured while swarming. No further increase of the dispersal occurred during the postrelease period investigated (from day 4 to day 7 after release). The mean survival rate at the release was 0.51 for FP-marked males and 0.81 for WB0 males. The data obtained are discussed for their significance in planning sterile insect technique programs against Ae. albopictus. PMID:21175057

  18. [Thermo-sensitive period and critical temperature of fertility transition of thermo-photo-sensitive genic male sterile wheat].

    PubMed

    Zhang, Jiankui; Feng, Li; He, Liren; Yu, Guodong

    2003-01-01

    The thermo-sensitive period and the critical temperature of fertility transition of C49S, a principal thermo-photosensitive genic male sterile line in two-line hybrid wheat, was studied in the growth chambers for controlling temperature and photoperiod. The seeds were sown on different time for some years. The results showed that the thermo-sensitive period in fertility expression of C49S was from PMC formation stage to mature pollen stage, and there were two most sensitive stages to temperature on fertility expression. One was the PMC meiosis stage, and the other was the middle microspore stage. The critical temperatures evoking a complete male sterility were the mean minimum temperature at PMC meiosis stage (Tmin1), the mean temperature at microspore stage (T2) and the mean minimum temperature at microspore stage (Tmin2) lower than 8.5 degrees C, 13.5 degrees C and 10.5 degrees C, respectively. The critical temperatures keeping a nearly normal male fertility Tmin1 and T2 and Tmin2 were higher than 11.5 degrees C, 15.0 degrees C and 12.5 degrees C, respectively. The value as well as the conditions and the risks of thermo-photo-sensitive genic male sterile line of wheat applied to hybrid wheat were evaluated in this paper. PMID:12722439

  19. DNA methylation changes in photoperiod-thermo-sensitive male sterile rice PA64S under two different conditions.

    PubMed

    Chen, Xiaojun; Hu, Jihong; Zhang, Hongyuan; Ding, Yi

    2014-03-01

    Epigenetic modification can occur at a high frequency in crop plants and might generate phenotypic variation without changes in DNA sequences. DNA methylation is an important epigenetic modification that may contribute to environmentally-induced phenotypic variations by regulating gene expression. Rice Photoperiod-Thermo-Sensitive Genic Male Sterile (PTGMS) lines can transform from sterility to fertility under lower temperatures and short-day (SD) conditions during anther development. So far, little is known about the DNA methylation variation of PTGMS throughout the genome in rice. In this study, we investigated DNA cytosine methylation alterations in the young panicles of PTGMS line PA64S under two different conditions using methylation sensitive amplified polymorphism (MSAP) method. Compared with the DNA methylation level of PA64S under lower temperatures and SD conditions (fertility), higher methylation was observed in PA64S (sterility). The sequences of 25 differentially amplified fragments were successfully obtained and annotated. Three methylated fragments, which are homologous to D2, NAD7 and psaA, were confirmed by bisulfite sequencing and their expression levels were also evaluated by qPCR. Real time quantitative PCR analysis revealed that five of the six selected methylated genes were downregulated in PA64S (sterility). These results suggested that DNA methylation may be involved in the sterility-fertility transition of PA64S under two different environmental conditions. PMID:24365594

  20. Discovery of mitochondrial chimeric-gene associated with cytoplasmic male sterility of HL-rice

    Microsoft Academic Search

    Ping Yi; Li Wang; Qingping Sun; Yingguo Zhu

    2002-01-01

    The mitochondrial genome libraries of HL-type sterile line (A) and maintainer line(B) have been constructed. Mitochondrial\\u000a gene, atp6, was used to screen libraries, due to the different Southern and Northern blot results between sterile and maintainer line.\\u000a Sequencing analysis of positive clones proved that there were two copies of atp6 gene in sterile line and only one in maintainer line.

  1. Restoration of fertility by antisense RNA in genetically engineered male sterile tobacco plants.

    PubMed

    Schmülling, T; Röhrig, H; Pilz, S; Walden, R; Schell, J

    1993-03-01

    Transgenic tobacco plants (Nicotiana tabacum L.) expressing the rolC gene of Agrobacterium rhizogenes under the transcriptional control of the 35S RNA promoter are male sterile. When these plants are genetically crossed with others containing the rolC gene linked in antisense orientation to the 35S RNA promoter, hybrid progeny display restoration of male fertility. Moreover, hybrid progeny are revertant for other features of the rolC phenotype, such as restoration of plant height, leaf pigment content and female fertility. The level of restoration of the characteristics of untransformed tobacco appeared to be independent of the steady-state level of antisense RNA. Addition of six transcriptional enhancer sequences upstream of the 35S transcriptional start region in the antisense construct led to a higher steady-state level of antisense RNA than that produced using a promoter linked to a single enhancer sequence. However no significant difference was observed in the level of attenuation of the rolC phenotype in the progeny of crosses with either one or six transcriptional enhancers linked to the antisense rolC gene. Antisense constructs comprising only 189 bp of the rolC 5' coding region appeared less efficient in attenuating the rolC phenotype than those including the whole rolC coding region as well as its 3' untranslated region. Furthermore, results from experiments on light-controlled rolC gene expression indicate that microsporogenesis is sensitive to rolC gene action during the early stages of flower development. PMID:8483453

  2. PPL2ab neurons restore sexual responses in aged Drosophila males through dopamine.

    PubMed

    Kuo, Shu-Yun; Wu, Chia-Lin; Hsieh, Min-Yen; Lin, Chen-Ta; Wen, Rong-Kun; Chen, Lien-Cheng; Chen, Yu-Hui; Yu, Yhu-Wei; Wang, Horng-Dar; Su, Yi-Ju; Lin, Chun-Ju; Yang, Cian-Yi; Guan, Hsien-Yu; Wang, Pei-Yu; Lan, Tsuo-Hung; Fu, Tsai-Feng

    2015-01-01

    Male sexual desire typically declines with ageing. However, our understanding of the neurobiological basis for this phenomenon is limited by our knowledge of the brain circuitry and neuronal pathways controlling male sexual desire. A number of studies across species suggest that dopamine (DA) affects sexual desire. Here we use genetic tools and behavioural assays to identify a novel subset of DA neurons that regulate age-associated male courtship activity in Drosophila. We find that increasing DA levels in a subset of cells in the PPL2ab neuronal cluster is necessary and sufficient for increased sustained courtship in both young and aged male flies. Our results indicate that preventing the age-related decline in DA levels in PPL2ab neurons alleviates diminished courtship behaviours in male Drosophila. These results may provide the foundation for deciphering the circuitry involved in sexual motivation in the male Drosophila brain. PMID:26123524

  3. PPL2ab neurons restore sexual responses in aged Drosophila males through dopamine

    PubMed Central

    Kuo, Shu-Yun; Wu, Chia-Lin; Hsieh, Min-Yen; Lin, Chen-Ta; Wen, Rong-Kun; Chen, Lien-Cheng; Chen, Yu-Hui; Yu, Yhu-Wei; Wang, Horng-Dar; Su, Yi-Ju; Lin, Chun-Ju; Yang, Cian-Yi; Guan, Hsien-Yu; Wang, Pei-Yu; Lan, Tsuo-Hung; Fu, Tsai-Feng

    2015-01-01

    Male sexual desire typically declines with ageing. However, our understanding of the neurobiological basis for this phenomenon is limited by our knowledge of the brain circuitry and neuronal pathways controlling male sexual desire. A number of studies across species suggest that dopamine (DA) affects sexual desire. Here we use genetic tools and behavioural assays to identify a novel subset of DA neurons that regulate age-associated male courtship activity in Drosophila. We find that increasing DA levels in a subset of cells in the PPL2ab neuronal cluster is necessary and sufficient for increased sustained courtship in both young and aged male flies. Our results indicate that preventing the age-related decline in DA levels in PPL2ab neurons alleviates diminished courtship behaviours in male Drosophila. These results may provide the foundation for deciphering the circuitry involved in sexual motivation in the male Drosophila brain. PMID:26123524

  4. Molecular and biological studies on male-sterile cytoplasm in the Cruciferae. I. The origin and distribution of Ogura male-sterile cytoplasm in Japanese wild radishes ( Raphanus sativus L.) revealed by PCR-aided assay of their mitochondrial DNAs

    Microsoft Academic Search

    H. Yamagishi; T. Terachi

    1994-01-01

    Ogura male-sterile cytoplasm was surveyed in common Japanese radish cultivars and in wild radishes growing in various localities in Japan. Mitochondrial (mt) DNA rearrangement involving the atp6 gene was used as a molecular marker. To detect the mtDNA rearrangement, polymerase chain reactions (PCR) were designed to amplify the upstream region of the atp6 gene. The oligonucleotides homologous to the following

  5. Measurement of benign prostatic hyperplasia treatment effects on male sexual function

    PubMed Central

    Skolarus, TA; Wei, JT

    2010-01-01

    Benign prostatic hyperplasia (BPH) is the leading cause of lower urinary tract symptoms among the aging male population. Epidemiological, pathophysiological and clinical studies indicate that many of these men also suffer from declining sexual function, especially those undergoing treatment for their BPH-related urinary symptoms. Although urinary symptoms and quality of life may improve with BPH therapy, the resulting effects on sexual function vary by medical, surgical and minimally invasive approaches and have not been consistently reported. As comprehensive, validated instruments to measure male sexual function are now available for routine use in the clinical setting, urologists and primary care providers caring for patients with BPH have the opportunity to monitor both urinary and sexual function before, during and after BPH therapy. Herein, we describe the relationship between BPH and its treatments on male sexual function, the role of new measures for sexual functioning and opportunities for future work to improve the care of men suffering from both maladies. PMID:19536125

  6. Sexual objectification and the construction of whiteness in the gay male community.

    PubMed

    Teunis, Niels

    2007-01-01

    This paper presents interview data and media analysis on the gay male community in the USA. It describes how sexual objectification is more than the outcome of racism in the gay male community. Sexual objectification of gay men of colour in the USA produces a white sexual community. Ideologies of inclusivity and non-discrimination blind white gay men to the harmful effects of sexual objectification. Moreover, discussing negative effects of objectification is met with considerable resistance. The experiences of African American men, described in this paper, show the pervasiveness of sexual objectification. The sexual objectification of men of colour forces them to play specific roles in sexual encounters that are not necessarily of their own choosing. PMID:17457730

  7. Sexual selection for male dominance reduces opportunities for female mate choice in the European bitterling (Rhodeus sericeus)

    Microsoft Academic Search

    M. REICHARD; J. BRYJA; M. ONDRACKOVA; M. DAVIDOVA; P. KANIEWSKA; C. SMITH

    2005-01-01

    Sexual selection involves two main mechanisms: intrasexual competition for mates and intersexual mate choice. We experimentally separated intrasexual (male-male interference competition) and intersexual (female choice) components of sexual selection in a freshwater fish, the European bitterling ( Rhodeus sericeus ). We compared the roles of multiple morphological and behavioural traits in male success in both components of sexual com- petition,

  8. Partial mediation of strange-male-induced pregnancy blocks by sexual activity in mice (Mus musculus).

    PubMed

    de Catanzaro, D; Storey, A E

    1989-12-01

    Novel male house mice (Mus musculus) can disrupt early pregnancy in females. Previous research focused on pheromonal rather than behavioral mediation of this phenomenon. In Experiment 1, novel males were housed with females shortly after insemination. Litter production was negatively correlated with the males' sexual activity. Experiment 2 replicated this finding with a larger sample. In Experiment 3, females were exposed to castrated males. Testosterone-treated males completely blocked pregnancy, whereas untreated males did not. In Experiment 4, castrated testosterone-treated males were presented at intervals after insemination. Pregnancy was totally blocked at Days 3 and 4 and mostly blocked at Days 1 and 2 but was less affected at Days 5 and 6. In Experiment 5, females were exposed through a wire-mesh grid to castrated males. Pregnancies occurred in all conditions, even with testosterone-treated males. These data suggest a role for sexual activity in male-induced pregnancy blocks. PMID:2598624

  9. Localization and organization of tRNA genes on the mitochondrial genomes of fertile and male sterile lines of maize

    Microsoft Academic Search

    Abdourahamane Sangaré; Jacques-Henry Weil; Jean-Michel Grienenberger; Christiane Fauron; David Lonsdale

    1990-01-01

    Maize mitochondrial (mt) tRNA genes were localized on the mt master circles of two fertile lines (WF9-N and B37-N) and of one cytoplasmic male sterile line (B37-cmsT) of maize. The three genomes contain 16 tRNA genes with 14 different anticodons which correspond to 13 amino acids. Out of these 16 tRNA genes, 6 show a high degree of homology with

  10. Proteome Analysis of the Wild and YX-1 Male Sterile Mutant Anthers of Wolfberry (Lycium barbarum L.)

    PubMed Central

    Zheng, Rui; Sijun Yue; Xu, Xiaoyan; Liu, Jianyu; Xu, Qing; Wang, Xiaolin; Han, Lu; Yu, Deyue

    2012-01-01

    Pollen development is disturbed in the early tetrad stage of the YX-1 male sterile mutant of wolfberry (Lycium barbarum L.). The present study aimed to identify differentially expressed anther proteins and to reveal their possible roles in pollen development and male sterility. To address this question, the proteomes of the wild-type (WT) and YX-1 mutant were compared. Approximately 1760 protein spots on two-dimensional differential gel electrophoresis (2D-DIGE) gels were detected. A number of proteins whose accumulation levels were altered in YX-1 compared with WT were identified by mass spectrometry and the NCBInr and Viridiplantae EST databases. Proteins down-regulated in YX-1 anthers include ascorbate peroxidase (APX), putative glutamine synthetase (GS), ATP synthase subunits, chalcone synthase (CHS), CHS-like, putative callose synthase catalytic subunit, cysteine protease, 5B protein, enoyl-ACP reductase, 14-3-3 protein and basic transcription factor 3 (BTF3). Meanwhile, activities of APX and GS, RNA expression levels of apx and atp synthase beta subunit were low in YX-1 anthers which correlated with the expression of male sterility. In addition, several carbohydrate metabolism-related and photosynthesis-related enzymes were also present at lower levels in the mutant anthers. In contrast, 26S proteasome regulatory subunits, cysteine protease inhibitor, putative S-phase Kinase association Protein 1(SKP1), and aspartic protease, were expressed at higher levels in YX-1 anthers relative to WT anthers. Regulation of wolfberry pollen development involves a complex network of differentially expressed genes. The present study lays the foundation for future investigations of gene function linked with wolfberry pollen development and male sterility. PMID:22860020

  11. Characterization of cytoplasmic male sterility of rice with Lead Rice cytoplasm in comparison with that with Chinsurah Boro II cytoplasm

    Microsoft Academic Search

    Etsuko Itabashi; Tomohiko Kazama; Kinya Toriyama

    2009-01-01

    Rice with LD-type cytoplasmic male sterility (CMS) possesses the cytoplasm of ‘Lead Rice’ and its fertility is recovered by\\u000a a nuclear fertility restorer gene Rf1. Rf1 promotes processing of a CMS-associated mitochondrial RNA of atp6–orf79, which consists of atp6 and orf79, in BT-CMS with the cytoplasm of ‘Chinsurah Boro II’. In this study, we found that LD-cytoplasm contained a sequence

  12. Proteome analysis of the wild and YX-1 male sterile mutant anthers of wolfberry (Lycium barbarum L.).

    PubMed

    Zheng, Rui; Sijun Yue; Xu, Xiaoyan; Liu, Jianyu; Xu, Qing; Wang, Xiaolin; Han, Lu; Yu, Deyue

    2012-01-01

    Pollen development is disturbed in the early tetrad stage of the YX-1 male sterile mutant of wolfberry (Lycium barbarum L.). The present study aimed to identify differentially expressed anther proteins and to reveal their possible roles in pollen development and male sterility. To address this question, the proteomes of the wild-type (WT) and YX-1 mutant were compared. Approximately 1760 protein spots on two-dimensional differential gel electrophoresis (2D-DIGE) gels were detected. A number of proteins whose accumulation levels were altered in YX-1 compared with WT were identified by mass spectrometry and the NCBInr and Viridiplantae EST databases. Proteins down-regulated in YX-1 anthers include ascorbate peroxidase (APX), putative glutamine synthetase (GS), ATP synthase subunits, chalcone synthase (CHS), CHS-like, putative callose synthase catalytic subunit, cysteine protease, 5B protein, enoyl-ACP reductase, 14-3-3 protein and basic transcription factor 3 (BTF3). Meanwhile, activities of APX and GS, RNA expression levels of apx and atp synthase beta subunit were low in YX-1 anthers which correlated with the expression of male sterility. In addition, several carbohydrate metabolism-related and photosynthesis-related enzymes were also present at lower levels in the mutant anthers. In contrast, 26S proteasome regulatory subunits, cysteine protease inhibitor, putative S-phase Kinase association Protein 1(SKP1), and aspartic protease, were expressed at higher levels in YX-1 anthers relative to WT anthers. Regulation of wolfberry pollen development involves a complex network of differentially expressed genes. The present study lays the foundation for future investigations of gene function linked with wolfberry pollen development and male sterility. PMID:22860020

  13. Reversion of Texas male-sterile cytoplasm maize in culture to give fertile, T-toxin resistant plants

    Microsoft Academic Search

    R. I. S. Brettell; E. Thomas; D. S. Ingram

    1980-01-01

    Plants carrying Texas male-sterile (Tms) cytoplasm are normally sensitive to Drechslera maydis T-toxin. Tissue cultures were initiated from immature embryos of maize carrying Tms-cytoplasm, and plants were regenerated after selection for resistance to T-toxin. Fertile, T-toxin resistant plants were obtained from the unselected control cultures as well as from the selected material. In addition, one regenerant from an unselected culture

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

    PubMed Central

    Wang, Qi; Shih, Chungkun; Ren, Dong

    2013-01-01

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

  15. Complicity or conflict over sexual cannibalism? Male risk taking in the praying mantis Tenodera aridifolia sinensis.

    PubMed

    Lelito, Jonathan P; Brown, William D

    2006-08-01

    Male complicity versus conflict over sexual cannibalism in mantids remains extremely controversial, yet few studies have attempted to establish a causal relationship between risk of cannibalism and male reproductive behavior. We studied male risk-taking behavior in the praying mantid Tenodera aridifolia sinensis by altering the risk imposed by females and measuring changes in male behavior. We show that males were less likely to approach hungrier, more rapacious females, and when they did approach, they moved more slowly, courted with greater intensity, and mounted from a greater distance. Similarly, when forced to approach females head-on, within better view and better reach of females, males also approached more slowly and courted with greater intensity. Thus, males behaved in a manner clearly indicative of risk avoidance, and we support the hypothesis of sexual conflict over sexual cannibalism. PMID:16874635

  16. REGISTRATIONS OF C931, C941, CR11, AND CZ25/2 SELF-FERTILE, GENETIC-MALE-STERILE FACILITATED, RANDOM-MATED, SUGARBEET GERMPLASM POPULATIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugarbeet is naturally self-sterile and most germplasm can not be selfed to produce selfed progenies for breeding and genetic research. However, it is often very useful to be able to produce selfed progeny families. With the use of the genes for self-fertility and genetic-male-sterility, over the pa...

  17. Influence of methoprene and protein on survival, maturation and sexual performance of male Ceratitis capitata (Diptera:Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Mediterranean fruit fly (medfly), Ceratitis capitata (Wied.), like many other polifagous tephritids (Diptera: Tephritidae), adopts a lek as mating system. The sterile insect technique (SIT) requires the release of sterile males able to survive on the field, to compete with wild males, and attrac...

  18. Sneaky monkeys: an audience effect of male rhesus macaques (Macaca mulatta) on sexual behavior.

    PubMed

    Overduin-de Vries, A M; Massen, J J M; Spruijt, B M; Sterck, E H M

    2012-03-01

    Males and females have different sexual interests and subsequently may show conflicting sexual strategies. While dominant males try to monopolize females, promiscuity benefits females and subordinate males. One way to escape monopolization by dominant males is to copulate in their absence. We tested this inhibitory effect of males on the sexual behavior of their group members in captive group-living Rhesus macaques. Copulations between females and nonalpha males almost exclusively took place when the alpha male was out of sight. Furthermore, the inhibiting effect was not unique for the alpha male. An upcoming nonalpha male also inhibited copulations of its group members, and three other nonalpha males inhibited female copulation solicitations. Females adjusted their behavior to the presence of bystander males, as they initiated and accepted initiations more often in absence than in presence of bystander males. Although not significant, in males, a similar pattern was found. The observed reduction in mating behavior in presence of bystander males is in accordance with an "audience effect," in which the behavior is modulated in relation to the presence or absence of third parties. This audience effect may serve as an important mechanism to reduce (aggressive) interruptions of subordinate male copulations. PMID:24006540

  19. Sexual Behavior among Employed Male Rural Migrants in Shanghai, China

    ERIC Educational Resources Information Center

    He, Na; Detels, Roger; Chen, Zheng; Jiang, Qingwu; Zhu, Jinde; Dai, Yiqun; Wu, Min; Zhong, Xing; Fu, Chaowei; Gui, Dexin

    2006-01-01

    A study of sexual behavior in migrant men was conducted in construction sites, markets, and factories in Shanghai, the largest city in China. An anonymous, self-administered questionnaire was completed by the migrants. Among 986 sexually active men, 14% had had more than one sexual partner in their lifetime, 31% premarital sex, 3.3% oral sex, and…

  20. Sexual function in hypertensive males treated with lisinopril or atenolol

    Microsoft Academic Search

    Roberto Fogari; Annalisa Zoppi; Luca Corradi; Amedeo Mugellini; Luigi Poletti; Paola Lusardi

    1998-01-01

    To evaluate the effect of antihypertensive treatment on sexual activity, 90 hypertensive men, aged 40 to 49 years, all married and without history of sexual dysfunction were treated with 100 mg of atenolol or 20 mg of lisinopril for 16 weeks, according to a double-blind, randomized, cross-over design. During the first month of therapy, sexual activity, assessed as number of

  1. Premarital Sexual Behavior among male college students of Kathmandu, Nepal

    Microsoft Academic Search

    Ramesh Adhikari; Jyotsna Tamang

    2009-01-01

    BACKGROUND: In Nepal, as in other Asian countries, the issue of sexuality still remains a taboo. Despite this fact, an increasing number of sexual activities is being reported by Nepalese students. This trend warrants serious and timely attention. Due to the sensitivity of the topic of premarital sexuality, youth receive inadequate education, guidance and services on reproductive health. The main

  2. Sexual Harassment by Males Reduces Female Fecundity in the Alfalfa Leafcutting Bee (Megachile rotundata)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Under sexual conflict, males evolve traits to increase their mating and reproductive success that impose costs on females. Females evolve counter-adaptations to resist males and reduce those costs. Female resistance may instead serve as a mechanism for mate choice if the male-imposed costs are outwe...

  3. Male Sexual Polymorphism, Alternative Reproductive Tactics, and Androgens in Combtooth Blennies (Pisces: Blenniidae)

    Microsoft Academic Search

    Rui F. Oliveira; Adelino V. M. Canario; Matthew S. Grober

    2001-01-01

    In species in which intense intermale competition for the access to females is present males of lower competitive ability may adopt alternative reproductive tactics (ART) to get access to mates. These ART translate in many cases into male sexual polymorphism, with individuals following distinctly different tactics. Usually two alternative male morphs can be recognized in species with ART: (1) bourgeois

  4. Hair whorl direction and sexual orientation in human males.

    PubMed

    Rahman, Qazi; Clarke, Kenneth; Morera, Tirma

    2009-04-01

    Hair whorl direction is a somatic feature that is organized early during neurodevelopment and unlikely to be influenced by social factors. This study aimed to replicate a widely reported association by A. J. S. Klar (2003) between counterclockwise hair whorl direction and homosexuality in men, using more objective methodology. The authors took digital photographs of parietal surface hair whorls from 100 heterosexual men and 100 homosexual men who were predominantly right-handed. These images were rated for clockwise and counterclockwise direction (for which no more than 1 hair whorl was present) by 2 raters unaware of sexual orientation. The authors found no significant difference between heterosexual and homosexual men in hair whorl direction, but the authors did replicate the fraternal birth order effect (more older brothers for homosexual men). Number of older sisters was positively correlated with counterclockwise hair whorls in heterosexual men. These data were discussed in relation to prenatal factors assumed to play a role in the neurodevelopment of male homosexuality. PMID:19331448

  5. Sexually coercive behavior in male youth: population survey of general and specific risk factors.

    PubMed

    Kjellgren, Cecilia; Priebe, Gisela; Svedin, Carl Göran; Långström, Niklas

    2010-10-01

    Little is known about risk/protective factors for sexually coercive behavior in general population youth. We used a Swedish school-based population survey of sexual attitudes and experiences (response rate 77%) and investigated literature-based variables across sexually coercive (SEX), non-sexual conduct problem (CP), and normal control (NC) participants to identify general and specific risk/protective factors for sexual coercion. Among 1,933 male youth, 101 (5.2%) reported sexual coercion (ever talked or forced somebody into genital, oral, or anal sex) (SEX), 132 (6.8%) were classified as CP, and the remaining 1,700 (87.9%) as NC. Of 29 tested variables, 25 were more common in both SEX and CP compared to NC youth, including minority ethnicity, separated parents, vocational study program, risk-taking, aggressiveness, depressive symptoms, substance abuse, sexual victimization, extensive sexual experiences, and sexual preoccupation. When compared to CP youth only, SEX youth more often followed academic study programs, used less drugs and were less risk-taking. Further, SEX more frequently than CP youth reported gender stereotypic and pro-rape attitudes, sexual preoccupation, prostitution, and friends using violent porn. Finally, in a multivariate logistic regression, academic study program, pro-rape attitudes, sexual preoccupation, and less risk-taking independently remained more strongly associated with SEX compared to CP offending. In conclusion, several sociodemographic, family, and individual risk/protective factors were common to non-sexual and sexually coercive antisocial behavior in late adolescence. However, pro-rape cognitions, and sexual preoccupation, were sexuality-related, specific risk factors. The findings could inform preventive efforts and the assessment and treatment of sexually coercive male youth. PMID:19888644

  6. Cytological and Comparative Proteomic Analyses on Male Sterility in Brassica napus L. Induced by the Chemical Hybridization Agent Monosulphuron Ester Sodium

    PubMed Central

    Li, Zhanjie; Cui, Jianmin; Hu, Shengwu; Zhao, Huixian; Chen, Mingshun

    2013-01-01

    Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Monosulphuron ester sodium (MES), a new acetolactate synthase-inhibitor herbicide belonging to the sulphonylurea family, has been developed as an effective CHA to induce male sterility in rapeseed (Brassica napus L.). To understand MES-induced male sterility in rapeseed better, comparative cytological and proteomic analyses were conducted in this study. Cytological analysis indicated that defective tapetal cells and abnormal microspores were gradually generated in the developing anthers of MES-treated plants at various development stages, resulting in unviable microspores and male sterility. A total of 141 differentially expressed proteins between the MES-treated and control plants were revealed, and 131 of them were further identified by MALDI-TOF/TOF MS. Most of these proteins decreased in abundance in tissues of MES-treated rapeseed plants, and only a few increased. Notably, some proteins were absent or induced in developing anthers after MES treatment. These proteins were involved in several processes that may be crucial for tapetum and microspore development. Down-regulation of these proteins may disrupt the coordination of developmental and metabolic processes, resulting in defective tapetum and abnormal microspores that lead to male sterility in MES-treated plants. Accordingly, a simple model of CHA-MES-induced male sterility in rapeseed was established. This study is the first cytological and dynamic proteomic investigation on CHA-MES-induced male sterility in rapeseed, and the results provide new insights into the molecular events of male sterility. PMID:24244648

  7. Different organization and altered transcription of the mitochondrial atp6 gene in the male-sterile cytoplasm of rapeseed ( Brassica napus L.)

    Microsoft Academic Search

    Hirokazu Handa; Kousuke Nakajima

    1992-01-01

    The Fo-ATPase subunit 6 gene (atp6) of rapeseed mitochondria has been isolated from both pol malesterile and normal (fertile) cytoplasms in order to determine whether the rearrangements around the atp6 locus in pol male-sterile cytoplasm play a role in cytoplasmic male-sterility (cms). The pol cms and normal atp6 genes are identical and encode a 261-amino acid polypeptide. As a result

  8. Microdeletions in interval 6 of the Y chromosome of males with idiopathic sterility point to disruption of AZF, a human spermatogenesis gene

    Microsoft Academic Search

    P. Vogt; A. C. Chandley; T. B. Hargreave; R. Keil; K. Ma; A. Sharkey

    1992-01-01

    For males with idiopathic sterility, a molecular screen specific for small lesions (microdeletions) in interval 6 of the Y chromosome was set up using 29 Y-DNA probes. A “de novo” microdeletion in Y interval 6 was detected in 2 out of 19 “chromosomally normal” sterile males. The first microdeletion includes the Y-DNA probes pY6HP35 and 12f3; the second microdeletion includes

  9. Sequencing of the chloroplast genomes of cytoplasmic male-sterile and male-fertile lines of soybean and identification of polymorphic markers.

    PubMed

    Lin, Chunjing; Zhang, Chunbao; Zhao, Hongkun; Xing, Shaochen; Wang, Yumin; Liu, Xiaodong; Yuan, Cuiping; Zhao, Limei; Dong, Yingshan

    2014-12-01

    The RN-type cytoplasmic male sterility (CMS) system used to develop Hybsoy-1, the first commercial hybrid soybean, has been subsequently applied to generate nearly all released soybean hybrids. Although more than 3 years are needed to classify sterile (S) and normal male-fertile (F) cytoplasms by conventional crossing, such classifications can be performed rapidly using organellar DNA-based molecular markers. Except for fertility, the agronomic traits of CMS hybrid soybean sterile and maintainer lines are identical. Consequently, it is difficult to distinguish them by routine visual inspection in the mixture arising in the course of field planting and harvesting during breeding. In this study, we performed next-generation sequencing of chloroplast DNAs of F- and S-cytoplasmic soybeans, assembled and annotated the genomes, and identified polymorphisms distinguishing them. Chloroplast DNAs of F and S cytoplasms were very similar in size (152,215 and 152,222 base pairs) and GC contents (35.37%). Among 23 shared SNPs in gene coding regions, we identified four that could be used in conjunction with restriction endonucleases to distinguish S and F cytoplasms. Although CMS is likely associated with mitochondrial DNA, maternal transmission of mitochondrial and chloroplast DNAs allows polymorphisms in either genome to be used to classify soybean cytoplasms, aiding hybrid soybean cultivar development. PMID:25443847

  10. Genetic Architecture of Hybrid Male Sterility in Drosophila: Analysis of Intraspecies Variation for Interspecies Isolation

    Microsoft Academic Search

    Laura K. Reed; Brooke A. Laflamme; Therese A. Markow; Pawel Michalak

    2008-01-01

    BackgroundThe genetic basis of postzygotic isolation is a central puzzle in evolutionary biology. Evolutionary forces causing hybrid sterility or inviability act on the responsible genes while they still are polymorphic, thus we have to study these traits as they arise, before isolation is complete.Methodology\\/Principal FindingsIsofemale strains of D. mojavensis vary significantly in their production of sterile F1 sons when females

  11. Tolerance of queer male performances of gender and sexuality in Rio de Janeiro 

    E-print Network

    Furlong, Anthony Brendan

    2012-11-29

    Although social research on sexuality is growing in Latin America, studies into tolerance are scarce. The purpose of this research was to investigate the relationship between queer male practices and tolerance amongst a ...

  12. Association analysis between the tag SNP for sonic hedgehog rs9333613 polymorphism and male sexual orientation.

    PubMed

    Wang, Binbin; Zhou, Sirui; Hong, Fuchang; Wang, Jing; Liu, Xiaoli; Cai, Yumao; Wang, Feng; Feng, Tiejian; Ma, Xu

    2012-01-01

    Male sexual orientation has been proposed to have genetic components, but previously suggested candidate genes have all received negative results. The human sonic hedgehog (SHH) gene is located in the 7q36 region, which was linked to male sexual orientation in a previous genome-wide association study. SHH is known to play an important role in embryo patterning, and there is evidence connecting it to sexual orientation. In this study, we performed an association analysis of the SHH tag single nucleotide polymorphism rs9333613 in 361 subjects and 319 Chinese male controls. We find a significant difference in genotype and allele distribution between identified homosexuals and heterosexual control subjects, suggesting that the SHH gene could potentially be associated with male sexual orientation. PMID:21940988

  13. DISTURBED SEXUAL CHARACTERISITCS IN MALE MOSQUITOFISH (GAMBUSIA HOLBROOKI) FROM A LAKE CONTAMINATED WITH ENDOCRINE DISRUPTORS.

    EPA Science Inventory

    Previous laboratory studies have demonstrated that estrogenic and antiandrogenic chemicals can alter several sexual characteristics in male poeciliid fishes. Whether similar disturbances occur under field conditions remains to be confirmed. Lake Apopka, Florida, is contaminated w...

  14. Inactivation of the UGPase1 gene causes genic male sterility and endosperm chalkiness in rice (Oryza sativa L.)

    PubMed Central

    Woo, Mi-Ok; Ham, Tae-Ho; Ji, Hyeon-So; Choi, Min-Seon; Jiang, Wenzhu; Chu, Sang-Ho; Piao, Rihua; Chin, Joong-Hyoun; Kim, Jung-A; Park, Bong Soo; Seo, Hak Soo; Jwa, Nam-Soo; McCouch, Susan; Koh, Hee-Jong

    2008-01-01

    A rice genic male-sterility gene ms-h is recessive and has a pleiotropic effect on the chalky endosperm. After fine mapping, nucleotide sequencing analysis of the ms-h gene revealed a single nucleotide substitution at the 3?-splice junction of the 14th intron of the UDP-glucose pyrophosphorylase 1 (UGPase1; EC2.7.7.9) gene, which causes the expression of two mature transcripts with abnormal sizes caused by the aberrant splicing. An in vitro functional assay showed that both proteins encoded by the two abnormal transcripts have no UGPase activity. The suppression of UGPase by the introduction of a UGPase1-RNAi construct in wild-type plants nearly eliminated seed set because of the male defect, with developmental retardation similar to the ms-h mutant phenotype, whereas overexpression of UGPase1 in ms-h mutant plants restored male fertility and the transformants produced T1 seeds that segregated into normal and chalky endosperms. In addition, both phenotypes were co-segregated with the UGPase1 transgene in segregating T1 plants, which demonstrates that UGPase1 has functional roles in both male sterility and the development of a chalky endosperm. Our results suggest that UGPase1 plays a key role in pollen development as well as seed carbohydrate metabolism. PMID:18182026

  15. Linkage between sexual orientation and chromosome Xq28 in males but not in females

    Microsoft Academic Search

    Stella Hu; Angela M. L. Pattatucci; Chavis Patterson; Lin Li; David W. Fulker; Stacey S. Cherny; Leonid Kruglyak; Dean H. Hamer

    1995-01-01

    We have extended our analysis of the role of the long arm of the X chromosome (Xq28) in sexual orientation by DNA linkage analyses of two newly ascertained series of families that contained either two gay brothers or two lesbian sisters as well as heterosexual siblings. Linkage between the Xq28 markers and sexual orientation was detected for the gay male

  16. A Male Poecillid's Sexually Dimorphic Body Plan, Behavior, and Nervous System

    E-print Network

    Lauder, George V.

    SYMPOSIUM A Male Poecillid's Sexually Dimorphic Body Plan, Behavior, and Nervous System Nydia L's sexually dimorphic body plan, behavior, and nervous system, including work dating from the mid 1800s movements. Recent work on the nervous system demonstrated dye-coupling between motor neurons

  17. Predictors of Sexually Coercive Behavior in a Nationally Representative Sample of Adolescent Males

    ERIC Educational Resources Information Center

    Casey, Erin A.; Beadnell, Blair; Lindhorst, Taryn P.

    2009-01-01

    Data from male participants in the National Longitudinal Study of Adolescent Health are used to examine childhood predictors of late adolescent and early adulthood sexually coercive behavior and adolescent mediators of these relationships. A path analysis shows that experiencing sexual abuse as a child has a direct effect on perpetrating…

  18. Gender Differences in Experiences of Sexual Harassment: Data from a Male-Dominated Environment

    ERIC Educational Resources Information Center

    Street, Amy E.; Gradus, Jaimie L.; Stafford, Jane; Kelly, Kacie

    2007-01-01

    The goal of this investigation was to examine gender differences in experiences of sexual harassment during military service and the negative mental health symptoms associated with these experiences. Female (n = 2,319) and male (n = 1,627) former reservists were surveyed about sexual harassment during their military service and current mental…

  19. Psychiatric Symptoms as a Predictor of Sexual Aggression among Male College Students

    Microsoft Academic Search

    Esther J. Calzada; Elissa J. Brown; Megan E. Doyle

    2011-01-01

    The goal of this investigation was to examine psychiatric symptoms as predictors of the frequency and severity of sexually aggressive behaviors that had been perpetrated by college-aged men in the past year. Over 400 undergraduate males completed an assessment of sexual aggression, athletic involvement, fraternity affiliation, alcohol and drug use, mistrust of women, depression, and social anxiety. More than 40%

  20. Individual, Family, Peer, and Academic Characteristics of Male Juvenile Sexual Offenders

    ERIC Educational Resources Information Center

    Ronis, Scott T.; Borduin, Charles M.

    2007-01-01

    This study examined the individual functioning, interpersonal relations, and academic performance of 115 male juveniles who were divided into 5 demographically matched groups (sexual offenders with peer/adult victims, sexual offenders with child victims, violent nonsexual offenders, nonviolent nonsexual offenders, and nondelinquent youths).…

  1. The effect of mood on opposite-sex judgments of males' commitment and females' sexual intent

    Microsoft Academic Search

    Mark Stokes

    Gender differences in perceptions of sexual intent and commitment have been the subject of formal and informal inquiry for considerable time. One evolutionary theory, Error Management Theory (EMT), predicts that opposite-sex perceptions of female sexual intent and male commitment intent reflect intrinsic biases that minimize gender-specific evolutionary costs. The results supporting these hypotheses were obtained from subjects regardless of mood.

  2. Development of sexual behavior over several serving capacity tests in male goats

    Microsoft Academic Search

    D. Bradley Imwalle; Larry S. Katz

    2004-01-01

    Results from previous research suggest that male goats, cattle and swine do not require prior sexual experience as juveniles to exhibit their full potential in serving capacity tests as adults. Preliminary data in our laboratory indicate that juvenile goats exhibit profound separation stress from pen mates when acclimating to a novel space, such as during a sexual performance test. Performance

  3. Hormonal regulation of brain circuits mediating male sexual behavior in birds

    Microsoft Academic Search

    Gregory F. Ball; Jacques Balthazart

    2004-01-01

    Male sexual behavior in both field and laboratory settings has been studied in birds since the 19th century. Birds are valuable for the investigation of the neuroendocrine mechanisms of sexual behavior, because their behavior can be studied in the context of a large amount of field data, well-defined neural circuits related to reproductive behavior have been described, and the avian

  4. Female aggregation and male competition reduce costs of sexual harassment in the mosquitofish Gambusia holbrooki

    Microsoft Academic Search

    Andrea Pilastro; Stefano Benetton; Angelo Bisazza

    2003-01-01

    Male mosquitofish allocate a large proportion of their time budget to attempting to inseminate unreceptive females. Because females invest considerable time and energy in avoiding unwanted copulations, sexual harassment is expected to conflict with other activities such as foraging. We found that sexual harassment more than halved the foraging efficiency of the female in a task requiring the retrieval of

  5. A possible non-sexual origin of mate preference: are male guppies mimicking fruit?

    Microsoft Academic Search

    F. Helen Rodd; Kimberly A. Hughes; Gregory F. Grether; Colette T. Baril

    2002-01-01

    In most animals, the origins of mating preferences are not clear. Thesensory-bias' hypothesis proposes that biases in female sensory or neural systems are important in triggering sexual selection and in determin- ing which male traits will become elaborated into sexual ornaments. Subsequently, other mechanisms can evolve for discriminating between high- and low-quality mates. Female guppies (Poecilia reticulata) gener- ally show

  6. Predictors of sexual aggression among a national sample of male college students.

    PubMed

    Koss, M P; Dinero, T E

    1988-01-01

    An approximately representative national sample of 2,972 male students at 32 U.S. institutions of higher education was surveyed regarding their use of several degrees of verbal coercion and physical force to obtain sexual intimacy with women without consent. The most severe form of sexual aggression each man reported was used to classify him into one of five groups: sexually nonaggressive, sexual coercion, sexual contact, attempted rape, or rape. Respondents also provided data that was grouped into three blocks of variables: early experiences (family violence exposure, childhood sexual abuse, age of sexual initiation), psychological characteristics (MMPI Scale 4, Hostility Toward Women, rape supportive beliefs, gender role orientation), and current behavior (alcohol use, pornography use, male bonding, sexual values and activity, conflict tactics). Data were analysed via blockwise discriminant function analysis. Variables were entered following a suggested development sequence. Specifically, all early experience variables were entered first as a block. Then the entire set of psychological characteristics were entered stepwise followed by all the current behavior variables. Variables from all three blocks entered the model. The classification rates have been discussed and the implications of the analyses for future causal models of male sexual aggression considered. PMID:3421588

  7. A Meta-Analysis of Risky Sexual Behaviour among Male Youth in Developing Countries

    PubMed Central

    Berhan, Asres

    2015-01-01

    The purpose of this meta-analysis was to assess the association between risky sexual behaviour and level of education and economic status in male youth. Previous tests of the association of risky sexual behaviour with levels of education and economic status have yielded inconsistent results. Using data from 26 countries, from both within and outside Africa, we performed a meta-analysis with a specific focus on male youths' risky sexual behaviour. We applied a random effects analytic model and calculated a pooled odds ratio. Out of 19,148 males aged 15–24 years who reported having sexual intercourse in the 12 months preceding the survey, 75% engaged in higher-risk sex. The proportion of higher-risk sex among male youth aged 15–19 years was nearly 90% in 21 of the 26 countries. The pooled odds ratio showed a statistically significant association of higher-risk sex with male youth younger than 20 years, living in urban centers, well educated, and of a high economic status. The overall proportion of condom use during youths' most recent higher-risk sexual encounter was 40% and 51% among 15–19-year-olds and 20–24-year-olds, respectively. Our findings suggest that male youth's socioeconomic status is directly related to the likelihood that they practice higher-risk sex. The relationship between income and sexual behaviour should be explored further. PMID:25709840

  8. Low Mate Encounter Rate Increases Male Risk Taking in a Sexually Cannibalistic Praying Mantis

    PubMed Central

    Brown, William D.; Muntz, Gregory A.; Ladowski, Alexander J.

    2012-01-01

    Male praying mantises are forced into the ultimate trade-off of mating versus complete loss of future reproduction if they fall prey to a female. The balance of this trade-off will depend both on (1) the level of predatory risk imposed by females and (2) the frequency of mating opportunities for males. We report the results of a set of experiments that examine the effects of these two variables on male risk-taking behavior and the frequency of sexual cannibalism in the praying mantis Tenodera sinensis. We experimentally altered the rate at which males encountered females and measured male approach and courtship behavior under conditions of high and low risk of being attacked by females. We show that male risk taking depends on prior access to females. Males with restricted access to females showed greater risk-taking behavior. When males were given daily female encounters, they responded to greater female-imposed risk by slowing their rate of approach and remained a greater distance from a potential mate. In contrast, males without recent access to mates were greater risk-takers; they approached females more rapidly and to closer proximity, regardless of risk. In a second experiment, we altered male encounter rate with females and measured rates of sexual cannibalism when paired with hungry or well-fed females. Greater risk-taking behavior by males with low mate encounter rates resulted in high rates of sexual cannibalism when these males were paired with hungry females. PMID:22558146

  9. Low mate encounter rate increases male risk taking in a sexually cannibalistic praying mantis.

    PubMed

    Brown, William D; Muntz, Gregory A; Ladowski, Alexander J

    2012-01-01

    Male praying mantises are forced into the ultimate trade-off of mating versus complete loss of future reproduction if they fall prey to a female. The balance of this trade-off will depend both on (1) the level of predatory risk imposed by females and (2) the frequency of mating opportunities for males. We report the results of a set of experiments that examine the effects of these two variables on male risk-taking behavior and the frequency of sexual cannibalism in the praying mantis Tenodera sinensis. We experimentally altered the rate at which males encountered females and measured male approach and courtship behavior under conditions of high and low risk of being attacked by females. We show that male risk taking depends on prior access to females. Males with restricted access to females showed greater risk-taking behavior. When males were given daily female encounters, they responded to greater female-imposed risk by slowing their rate of approach and remained a greater distance from a potential mate. In contrast, males without recent access to mates were greater risk-takers; they approached females more rapidly and to closer proximity, regardless of risk. In a second experiment, we altered male encounter rate with females and measured rates of sexual cannibalism when paired with hungry or well-fed females. Greater risk-taking behavior by males with low mate encounter rates resulted in high rates of sexual cannibalism when these males were paired with hungry females. PMID:22558146

  10. Female contact modulates male aggression via a sexually dimorphic GABAergic circuit in Drosophila

    PubMed Central

    Yuan, Quan; Song, Yuanquan; Yang, Chung-Hui; Jan, Lily Yeh; Jan, Yuh Nung

    2014-01-01

    Intraspecific male-male aggression, important for sexual selection, is regulated by environment, experience and internal states through largely undefined molecular and cellular mechanisms. To understand the basic neural pathway underlying the modulation of this innate behavior, we established a behavioral paradigm in Drosophila melanogaster and investigated the relationship between sexual experience and aggression. In the presence of mating partners, adult male flies exhibited elevated levels of aggression, which was largely suppressed by prior exposure to females via a sexually dimorphic neural mechanism. The suppression involved the ability of male flies to detect females by contact chemosensation through the pheromone-sensing ion channel, ppk29, and was mediated by male specific GABAergic neurons acting upon GABA-a receptor RDL in target cells. Silencing or activation of this circuit led to dis-inhibition or elimination of sex-related aggression, respectively. We propose that the GABAergic inhibition represents a critical cellular mechanism that enables prior experience to modulate aggression. PMID:24241395

  11. Child Support Enforcement and Sexual Activity of Male Adolescents

    ERIC Educational Resources Information Center

    Huang, Chien-Chung; Han, Wen-Jui

    2007-01-01

    Strong child support enforcement requires fathers to take financial responsibility for their children and may also encourage more responsible sexual behavior. Using the 1997-2001 waves of the 1997 National Longitudinal Survey of Youth (N = 4,272), this article examines the association between child support enforcement and the sexual activity of…

  12. Male sexual dysfunction and HIV--a clinical perspective.

    PubMed

    Santi, Daniele; Brigante, Giulia; Zona, Stefano; Guaraldi, Giovanni; Rochira, Vincenzo

    2014-02-01

    Sexual dysfunction in men with HIV is often overlooked by clinicians owing to many factors, including the taboo of sexuality. The improved life expectancy of patients with HIV requires physicians to consider their general wellbeing and sexual health with a renewed interest. However, data on sexual dysfunction in those with HIV are scarce. Erectile dysfunction (ED) is the most common sexual dysfunction in men, with a prevalence of ?30-50% and is frequent even in men <40 years of age. HIV infection itself is the strongest predictor of ED, and many factors related to the infection-fear of virus transmission, changes in body image, HIV-related comorbidities, infection stigma, obligatory condom use-all impair erectile function. The diagnosis and treatment of sexual dysfunction is based on a multidisciplinary approach, which involves specialists in both infectious diseases and sexual medicine. Particular attention should be paid to the promotion of safer sex in these patients. This Review, describes the issues surrounding sexual dysfunction in men with HIV and aims to provide clinical advice for the physician treating these patients. PMID:24394405

  13. Basic studies on hybrid wheat breeding : VIII. A new male sterility-fertility restoration system in common wheat utilizing the cytoplasms of Aegilops kotschyi and Ae. variabilis.

    PubMed

    Mukai, Y; Tsunewaki, K

    1979-07-01

    The nuclei of 12 common wheats (genome constitution AABBDD) were placed into the cytoplasms of Aegilops kotschyi and Ae. variabilis (both C(u)C(u)S(v)S(v)) by repeated backcrosses. Using these nucleus-cytoplasm hybrids, male sterility-fertility restoration relationship was investigated. Male sterility was expressed by these cytoplasms only in Slm, Splt and Mch. The other nine common wheat nuclei gave normal fertility against these cytoplasms. These cytoplasms were compared with the Triticum timopheevi cytoplasm that is now widely used in the hybrid wheat breeding program in order to investigate their effects on important agronomic traits of the 12 common wheats: The kotschyi and variabilis cytoplasms were as good as the timopheevi cytoplasm in this respect.The F1 hybrid between (kotschyi)- or (variabilis)-Splt and CS showed normal fertility. Segregation of the fertiles and steriles in their F2 generations followed the simple Mendelian fashion, i.e., 3 fertile?1 sterile. Thus, the fertility restoration in this case is mainly controlled by a single dominant gene which will be designated as Rfv1. To determine its location, ditelo-lBS and -lBL of CS were crossed as male parents to male sterile (kotschyi)- and (variabilis)-Splt. The F1 hybrids between the male sterile Spit's and CS ditelo-lBS became male fertile, while those between the male sterile Spit's and CS ditelo-lBL became completely male sterile. Thus, the location of the gene Rfv1 has been determined to be on the short arm of chromosome lB of CS. Furthermore, a close relationship between the fertility-restoring genes and the nucleolus organizer region was pointed out.Finally, the schemes of breeding the male sterile lines of a cultivar with these cytoplasms, and its maintainer line were formulated. The following two points were considered as the advantages of the present male sterility-fertility restoration system over that using the timopheevi cytoplasm in breeding hybrid wheat: (1) easier fertility restoration in F1 hybrids, and (2) no need of breeding the restorer line. PMID:24310337

  14. Female Sexual Polymorphism and Fecundity Consequences of Male Mating Harassment in the Wild

    PubMed Central

    Gosden, Thomas P.; Svensson, Erik I.

    2007-01-01

    Genetic and phenotypic variation in female response towards male mating attempts has been found in several laboratory studies, demonstrating sexually antagonistic co-evolution driven by mating costs on female fitness. Theoretical models suggest that the type and degree of genetic variation in female resistance could affect the evolutionary outcome of sexually antagonistic mating interactions, resulting in either rapid development of reproductive isolation and speciation or genetic clustering and female sexual polymorphisms. However, evidence for genetic variation of this kind in natural populations of non-model organisms is very limited. Likewise, we lack knowledge on female fecundity-consequences of matings and the degree of male mating harassment in natural settings. Here we present such data from natural populations of a colour polymorphic damselfly. Using a novel experimental technique of colour dusting males in the field, we show that heritable female colour morphs differ in their propensity to accept male mating attempts. These morphs also differ in their degree of resistance towards male mating attempts, the number of realized matings and in their fecundity-tolerance to matings and mating attempts. These results show that there may be genetic variation in both resistance and tolerance to male mating attempts (fitness consequences of matings) in natural populations, similar to the situation in plant-pathogen resistance systems. Male mating harassment could promote the maintenance of a sexual mating polymorphism in females, one of few empirical examples of sympatric genetic clusters maintained by sexual conflict. PMID:17593979

  15. Exploitation: comparing sexual and violent imagery of females and males in advertising.

    PubMed

    Rudman, W J; Verdi, P

    1993-01-01

    This study examines the way female and male models are portrayed in magazine advertisements. Specifically, we focus on differences in sex role stereotyping, sexual display of the body, and violent imagery. Data were collected from a stratified random sample of magazines displaying fashion and fitness advertisements (N = 254). Findings from the analysis show that females are more likely than males to be placed in submissive positions, sexually displayed, and subjects of violent imagery. Sexual display and violent imagery measures are the strongest predictors of subjective level of exploitation. PMID:8171873

  16. Effect of Curculigo orchioides on hyperglycemia-induced oligospermia and sexual dysfunction in male rats.

    PubMed

    Thakur, M; Chauhan, N S; Sharma, V; Dixit, V K; Bhargava, S

    2012-01-01

    Sustained hyperglycemia is considered as a major cause of sexual and erectile dysfunction in human population. Curculigo orchioides (CO) is considered as a sexual tonic in Ayurvedic system of medicine with potent antioxidant and adaptogenic properties. The aqueous extract of the herb was evaluated for its effectiveness against streptozotocin-induced hyperglycemic stress and subsequent sexual dysfunction due to hyperglycemia in male rats. Six groups with eight male rats in each group were used for this study and the study was carried out for 28 days. The body and organ weights of the animals were recorded. Behavioral analysis of rats was undertaken to observe the effect on mount, ejaculation and intromission (latencies and frequencies) and hesitation time. Blood glucose and serum testosterone levels were determined 28 days past treatment with CO at 100 and 200?mg?kg(-1) doses. Glibenclamide and sildenafil citrate were used as positive controls. This deleterious effect of sustained hyperglycemia and associated stress was prominently ameliorated in animals treated with aqueous extract of CO. CO treatment was helpful in ameliorating the damage caused by sustained hyperglycemia evidenced in the principle parameters viz. male sexual behavior, sperm count, penile erection index and seminal fructose content Antioxidant and anabolic activities of the extract under investigation could be a major attribute in preserving the sexual functions in hyperglycemic male rats. The study validates the use of CO in traditional medicine for curing diabetes-induced sexual dysfunction and compromised sexual potency. PMID:21918533

  17. Organization of actin cytoskeleton during meiosis I in a wheat thermo-sensitive genic male sterile line.

    PubMed

    Xu, Chenguang; Liu, Zetao; Zhang, Liping; Zhao, Changping; Yuan, Shaohua; Zhang, Fengting

    2013-02-01

    BS366 is a thermo-sensitive male sterile line of wheat (Triticum aestivum L.) for two-line hybrid breeding, which exhibits aberrant meiotic cytokinesis under low temperature. Through transcriptome analysis, a possible regulatory role for plant actin cytoskeleton was suggested. However, the organization of actin cytoskeleton in meiosis has been poorly understood so far. Here, fixed microsporocytes during meiosis were labeled with tetramethylrhodamine isothiocyanate-phalloidin and 4',6-diamidino-2-phenylindole. Quantities of fluorescent micrographs were captured using a confocal microscope, including the transient state from metaphase to telophase. We observed that actin filaments were abundant in typical kariokinetic spindle, central spindle (parallel microtubules or actin fibers between two separated chromosomes in anaphase), and phragmoplast. Interestingly, we identified the Chinese lantern-shaped actin phragmoplast in wheat meiosis for the first time. Under low temperature, phragmoplast actin filaments were chaotic and normal cell plate failed to form. These data provide new insights into the organization of actin filaments during male meiosis of plant and support a role of actin cytoskeleton in bringing about thermo-sensitive male sterility in wheat. PMID:22350736

  18. Can Ayahuasca and sleep loss change sexual performance in male rats?

    PubMed

    Alvarenga, T A; Polesel, D N; Matos, G; Garcia, V A; Costa, J L; Tufik, S; Andersen, M L

    2014-10-01

    The ingestion of the beverage Ayahuasca usually occurs in religious ceremonies that are performed during the night leading to sleep deprivation. The purpose of the present study was to characterize the acute effects of Ayahuasca upon the sexual response of sleep deprived male rats. One group of sexually experienced male Wistar rats were submitted to a paradoxical sleep deprivation (PSD) protocol for 96h, while another group spent the same amount of time in the home cage (CTRL). After this period, either saline or Ayahuasca drink (250, 500 and 1000?gmL(-1)) was administered by gavage and sexual behavior and hormonal concentrations were measured. Ayahuasca alone significantly decreased sexual performance at all doses. However, in sleep deprived rats, the lower dose increased sexual performance while the intermediate dose produced a detrimental effect on sexual response compared to the CTRL rats at the same dose. Regarding the hormonal analyses, a lower testosterone concentration was observed in sleep-deprived saline rats in relation to the CTRL group. Progesterone was significantly lower only in PSD rats at the dose 500?gmL(-1) compared with CTRL-500?gmL(-1) group. Corticosterone was unchanged among the groups evaluated. Our results suggest that Ayahuasca intake markedly impaired sexual performance alone, but, when combined with sleep deprivation, had significant, but heterogeneous, effects on male sexual response. PMID:25256159

  19. The Development of Conventional Sexual Partner Trajectories among African American Male Adolescents

    PubMed Central

    Kogan, Steven M.; Yu, Tianyi; Brody, Gene H.; Allen, Kimberly A.

    2012-01-01

    African American male youth disproportionately report involvement with multiple sexual partners, which increases their risk for sexually transmitted infections (STIs) and initiation of unplanned pregnancies. Little is known about the developmental precursors of sexual partner trajectories among African American male youth. Moreover, few studies focus on the many African American youth who evince highly conventional sexual partner trajectories, i.e., youth who have only one partner or abstain from sexual activity across time. Using four waves of data from a longitudinal study, we hypothesized that an accumulation of social and economic disadvantages in early adolescence would negatively influence youths’ conventional sexual partner trajectories in late adolescence. We expected these disadvantages to affect youths’ receipt of protective family processes and their reports of a set of intrapersonal processes (self-regulation, hope, and low levels of anger) linked to generally conventional behavior. Hypotheses were tested with data from 315 African American male youth from 11 to 18.5 years of age and their primary caregivers. Our results supported the hypotheses. Socioeconomic disadvantages during preadolescence predicted less involvement in conventional sexual partner trajectories from ages 16 to 18.5 years. This association was mediated by protective family processes and a set of interrelated intrapersonal protective processes. Preventive interventions designed to promote protective parenting and intrapersonal processes can be expected to promote sexual behavior trajectories characterized by abstinence or relations with very few partners. PMID:23150103

  20. Chronic Social Stress in Puberty Alters Appetitive Male Sexual Behavior and Neural Metabolic Activity

    PubMed Central

    Bastida, Christel C.; Puga, Frank; Gonzalez-Lima, Francisco; Jennings, Kimberly J.; Wommack, Joel C.; Delville, Yvon

    2014-01-01

    Repeated social subjugation in early puberty lowers testosterone levels. We used hamsters to investigate the effects of social subjugation on male sexual behavior and metabolic activity within neural systems controlling social and motivational behaviors. Subjugated animals were exposed daily to aggressive adult males in early puberty for postnatal days 28 to 42, while control animals were placed in empty clean cages. On postnatal day 45, they were tested for male sexual behavior in the presence of receptive female. Alternatively, they were tested for mate choice after placement at the base of a Y-maze containing a sexually receptive female in one tip of the maze and an ovariectomized one on the other. Social subjugation did not affect the capacity to mate with receptive females. Although control animals were fast to approach females and preferred ovariectomized individuals, subjugated animals stayed away from them and showed no preference. Cytochrome oxidase activity was reduced within the preoptic area and ventral tegmental area in subjugated hamsters. In addition, the correlation of metabolic activity of these areas with the bed nucleus of the stria terminalis and anterior parietal cortex changed significantly from positive in controls to negative in subjugated animals. These data show that at mid-puberty, while male hamsters are capable of mating, their appetitive sexual behavior is not fully mature and this aspect of male sexual behavior is responsive to social subjugation. Furthermore, metabolic activity and coordination of activity in brain areas related to sexual behavior and motivation was altered by social subjugation. PMID:24852486

  1. "This base stallion trade": he-whores and male sexuality on the early modern stage.

    PubMed

    Panek, Jennifer

    2010-01-01

    Recent scholarship on early modern male sexuality has stressed the threat that sexual relations with women were believed to pose to manhood. Focusing on such plays as Middleton's Your Five Gallants (c. 1608), Fletcher and Massinger's The Custom of The Country (c.1620), and Davenant's The Just Italian (1630), this paper analyzes representations of male prostitutes for women to argue that cultural attitudes toward male sexual performance were more complex and self-contradictory than generally acknowledged. The patriarchal codes that warned against effeminating sexual desire and advocated parsimonious seminal “spending” are undermined by their own inherent corollary: the most masculine man is one who can demonstrate unlimited seminal capacity. Furthermore, it has been posited that the early modern period marked the beginning of a shift from “reproductive” to “performative” constructions of manhood, in which the manhood-affirming aspects of male sexuality gradually became unmoored from their traditional association with bloodlines and attached instead to penetrative sexual conquest. The class implications of this shift inform patriarchal anxieties about the superior sexual stamina of servant-class men and their bodily “service” to elite women. Representing a fantasy of empowering male sexuality that relies on detaching virile performance from effeminating desire—a physiologically absurd notion—and on providing sexual “service” while leaving intact both class and gender hierarchies, a successful he-whore like Middleton's Tailby or Davenant's Sciolto playfully challenges the dictates of patriarchal masculinity by fulfilling them in absurd and unorthodox ways. Ultimately, he illuminates just how untenable those dictates might be. PMID:21114067

  2. Abstract Conditional handicap models of sexual selec-tion predict that sexual traits are reliable signals of male

    E-print Network

    Kotiaho, Janne S.

    (Zahavi 1977; Andersson 1982; Nur and Hasson 1984; Pomiankowski 1987; Grafen 1990a; Iwasa et al. 1991; Johnstone and Grafen 1992; Rowe and Houle 1996) suggest that secondary sexual traits may serve as honest trait size are smaller than for males in poor condition [Grafen 1990a; Johnstone and Grafen 1992

  3. Sexual selection, antennae length and the mating advantage of large males in Asellus aquaticus.

    PubMed

    Bertin, A; Cezilly, F

    2003-07-01

    In crustacean species with precopulatory mate-guarding, sexual size dimorphism has most often been regarded as the consequence of a large male advantage in contest competition for access to females. However, large body size in males may also be favoured indirectly through scramble competition. This might partly be the case if the actual target of selection is a morphological character, closely correlated with body size, involved in the detection of receptive females. We studied sexual selection on body size and antennae length in natural populations of Asellus aquaticus, an isopod species with precopulatory mate guarding. In this species, males are larger than females and male pairing success is positively related to body size. However, males also have longer antennae, relative to body size, than females, suggesting that this character may also be favoured by sexual selection. We used multivariate analysis of selection to assess the relative influences of body size and antennae length in five different populations in the field. Selection gradients indicated that overall body size was a better predictor of male pairing success than antennae length, although some variation was observed between sites. We then manipulated male antennae length in a series of experiments conducted in the laboratory, and compared the pairing ability of males with short or long antennae. Males with short antennae were less likely to detect, orient to and to pair with a receptive female compared to males with long antennae. We discuss the implications of our results for studies of male body size and sexual dimorphism in relation to sexual selection in crustaceans. PMID:14632233

  4. Sexual selection, antennae length and the mating advantage of large males in Asellus aquaticus.

    PubMed

    Bertin, A; Cézilly, F

    2003-05-01

    In crustacean species with precopulatory mate-guarding, sexual size dimorphism has most often been regarded as the consequence of a large male advantage in contest competition for access to females. However, large body size in males may also be favoured indirectly through scramble competition. This might partly be the case if the actual target of selection is a morphological character, closely correlated with body size, involved in the detection of receptive females. We studied sexual selection on body size and antennae length in natural populations of Asellus aquaticus, an isopod species with precopulatory mate guarding. In this species, males are larger than females and male pairing success is positively related to body size. However, males also have longer antennae, relative to body size, than females, suggesting that this character may also be favoured by sexual selection. We used multivariate analysis of selection to assess the relative influences of body size and antennae length in five different populations in the field. Selection gradients indicated that, overall, body size was a better predictor of male pairing success than antennae length, although some variation was observed between sites. We then manipulated male antennae length in a series of experiments conducted in the lab, and compared the pairing ability of males with short or long antennae. Males with short antennae were less likely to detect, orient to, and to pair with a receptive female compared with males with long antennae. We discuss the implications of our results for studies of male body size and sexual dimorphism in relation to sexual selection in crustaceans. PMID:14635849

  5. A linkage between DNA markers on the X chromosome and male sexual orientation

    Microsoft Academic Search

    D. H. Hamer; S. Hu; V. L. Magnuson; N. Hu; A. M. L. Pattatucci

    1993-01-01

    The role of genetics in male sexual orientation was investigated by pedigree and linkage analyses on 114 families of homosexual men. Increased rates of same-sex orientation were found in the maternal uncles and male cousins of these subjects, but not in their fathers or paternal relatives, suggesting the possibility of sex-linked transmission in a portion of the population. DNA linkage

  6. Sexual Experience Increases Nitric Oxide Synthase in the Medial Preoptic Area of Male Rats

    E-print Network

    Contreras, Robert J.

    Sexual Experience Increases Nitric Oxide Synthase in the Medial Preoptic Area of Male Rats Juan M. Dominguez, Jessica H. Brann, Mario Gil, and Elaine M. Hull Florida State University Nitric oxide levels of nitric oxide synthase (NOS) in the MPOA of male rats, regardless of whether they mated

  7. Author's personal copy The C. elegans adult male germline: Stem cells and sexual dimorphism

    E-print Network

    Kimble, Judith

    Author's personal copy The C. elegans adult male germline: Stem cells and sexual dimorphism Dyan E on an analysis of the adult C. elegans male germline, focusing on its predicted stem cell region at the distal by regeneration of a functional germline from the adult stem cell pool after starvation (Angelo and Van Gilst

  8. Exploring Taboos: Comparing Male- and Female-Perpetrated Child Sexual Abuse

    ERIC Educational Resources Information Center

    Peter, Tracey

    2009-01-01

    The objective of this article is to compare male- and female-perpetrated sexual abuse in terms of victim and abuser characteristics, type of abuse, family structure, and worker information. Bivariate tests of significance were performed on the 1998 Canadian Incidence Study of Reported Child Abuse and Neglect, which included 308 male and 37 female…

  9. Mites attack males of the sexually polymorphic tree Acer opalus more harmfully and more often

    Microsoft Academic Search

    M. VERDU; P. GARCIA-FAYOS; G. GLEISER

    2004-01-01

    Summary 1. Theory predicts that plants that achieve fitness more through male function may be less tolerant of herbivory than those that achieve fitness through the female function. We tested this hypothesis by measuring the degree of infection and damage inflicted by the gall-forming eriophyid mite Aceria macrorhynchus on three different sexual morphs (males, protandrous bisexuals and protogynous bisexuals) of

  10. The psychological impact of sexual abuse: Content analysis of interviews with male survivors

    Microsoft Academic Search

    David Lisak I

    1994-01-01

    Autobiographical interviews with 26 adult male survivors of childhood sexual abuse were audiotaped, transcribed verbatim and content analyzed to identify common psychological themes. Approximately equal numbers of men were abused by male and female perpetrators, almost half came from disrupted or violent homes and a majority had a history of substance abuse. Fifteen psychological themes were identified: Anger, Betrayal, Fear,

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

    Microsoft Academic Search

    Yasmina Katsulis; Alesha Durfee

    2012-01-01

    We investigated prevalence and correlates of sexual risk behaviours among male and female sex workers in Tijuana, Mexico, the busiest border crossing area on the US – Mexico border, analysing survey data from a purposive, cross-sectional sample of male and female sex workers who worked in a range of indoor and outdoor settings. Logistic regression was used to determine factors

  12. SEXUAL SIZE DIMORPHISM AND SURVIVAL OF MALE AND FEMALE BLACKBIRDS (ICTERIDAE)

    Microsoft Academic Search

    WILLIAM A. SEARCY; KEN YASUKAWA

    In a between-species comparison of icterids, male survival decreases relative to female survival as the degree of sexual size dimorphism increases. This result is consistent with the hypothesis that male size is limited by survival selection in icterids; the degree of size dimor- phism is known to correlate with the degree of polygyny in icterids, however, so the decreased relative

  13. Intraspecific Communication Through Chemical Signals in Female Mice: Reinforcing Properties of Involatile Male Sexual Pheromones

    Microsoft Academic Search

    Joana Martinez-Ricos; Carmen Agustin-Pavon; Enrique Lanuza; F. Martinez-Garcia

    2006-01-01

    In rodents, social and reproductive behaviors critically depend on chemical signals, including sexual pheromones that have been suggested (but not demonstrated) to be rewarding. In this work, we analyze this issue by studying the chemoinvestigatory behavior of adult female mice (without experience with male-derived chemicals) toward 1) the synthetic odorant citralva, 2) bedding soiled by different conspecifics (females, males, and

  14. Female mate choice in a mating system dominated by male sexual coercion

    Microsoft Academic Search

    Angelo Bisazza; Giorgio Vaccari; Andrea Pilastro

    In poeciliid fishes, males can gain copulation either by courting females or through sexual coercion. In some species these two tactics coexist. However, in about half of the poeciliids, males do not display, females never cooperate during copulation and all matings are achieved by thrusting the intromittent organ toward the genital pore of apparently unaware females. In one of these

  15. Clinical Evaluation of Non-surgical Sterilization of Male Cats with Single Intra-testicular Injection of Calcium Chloride

    PubMed Central

    2011-01-01

    Background Calcium chloride solution is an established injectable sterilant in dogs and other mammals. With cat populations a continuing problem, we sought to explore its first use in cats. Six cats per group were injected with 5%, 10% or 20% calcium chloride dihydrate in saline solution with lignocaine hydrochloride, a local anaesthetic. Results At the 60th day post-injection, cat testes were collected and showed complete testicular necrosis and replacement by fibrous tissue; very low sperm counts; and reduction of serum testosterone by at least 70% in 20% dose. Androgenic enzyme activities and their expressions were also reduced in all the treated groups along with intra-testicular testosterone concentration was also low. Increased testicular lipid peroxidation, with reduced antioxidants and mitochondrial membrane potential, were evident following calcium chloride treatments. However, there were no apparent changes in serum concentrations of cortisol, fasting blood sugar level, blood urea nitrogen, packed cell volume, or total serum protein following calcium chloride injection, suggesting that this method of sterilization is not associated with any general stress response. Conclusion Calcium chloride solution demonstrates potential for androgenesis-eliminating nonsurgical sterilization of male cats in addition to its proven efficacy in dogs and other mammals. PMID:21774835

  16. Forensic inpatient male sexual offenders: The impact of personality disorder and childhood sexual abuse

    Microsoft Academic Search

    Manuela Dudeck; Carsten Spitzer; Malte Stopsack; Harald J. Freyberger; Sven Barnow

    2007-01-01

    Given the great epidemiological, social, and psychological importance of sexual offences, and their deleterious consequences for victims, it seems vital to focus on potential risk factors for becoming a sexual offender. Our study aims to contribute to a better understanding of specific risk factors for sexual offenders by including a number of potentially important variables: biographical, clinical, and forensic. The

  17. Silencing of meiosis-critical genes for engineering male sterility in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Engineering sterile traits in plants through the tissue-specific expression of a cytotoxic gene provides an effective way for containing transgene flow; however, the microbial origin of cytotoxic genes has raised concerns. In an attempt to develop a safe alternative, we have chosen the meiosis-crit...

  18. [Mapping of two fertility-restoring gene for WA cytoplasmic male sterility in minghui63 using SSR markers].

    PubMed

    He, Guang-Hua; Wang, Wen-Ming; Liu, Guo-Qing; Hou, Lei; Xiao, Yue-Hua; Tang, Mei; Yang, Zheng-Lin; Pei, Yan

    2002-09-01

    F2 population derived from Shanyou63, F1 hybrid developed from the cross Zhenshan97 A/Zhenshan97B, was used in this study. Fertile bulk was constructed by polling equal amount of 15 highly fertile lines. Sterile bulk was obtained by pooling equal amount of 15 highly sterile lines. Minghui63 and Zhenshan97A, parents of Shanyou63, were analyzed with 302 pairs of SSR primers. 244 pairs of primers gave amplification products, of which 58 pairs of primers on 12 different chromosomes showed polymorphism between the two parents with polymorphic frequency up to 23.77%. Gene bulks were further assayed with the 5 pairs of primers. RM1 on chromosome 1 and RM258, RM304 on chromosome 10 was found to be polymorphic between the two gene bulks. In theory, there should be no difference detected between the two gene bulks except for the target traits governed by fertility-restoring genes. RM1, RM258 and RM304 were probably related to the restorer genes. Ten highly fertile and ten highly sterile lines were selected from F2 population of Shanyou63 to screen the gene bulks. The results showed that specific bands of Minghui63 were detected in all ten highly fertile lines while not observed in all the sterile lines. It indicated that the three SSR markers might be linked to fertility-restoring genes. Dominant lines were not selected due to their inalbility to distinguish recombinant lines from non-recombinant lines. Pure recessive lines were chosen to conduct mapping analysis. A total of 53 highly sterile lines were selected from 900 lines of Shanyou63 F2 population to estimate the genetic distance between three SSR markers and fertility-restoring genes respectively. The results demonstrated that recombination occurred in 2, 3, lines with RM1 and RM258 while no one with RM304. Using MAPMAKER/EXP 3.0, the genetic distance between RM1, RM258, RM304 and the related restorer genes were calculated as 1.9, 2.9 and 0.0 cM, respectively. It is possible that the fertility restoring gene(s) on chromosome 10 for three different types of cytoplasmic male sterility(WA, BT and HL) are of the same, or belong to a gene family. PMID:12561227

  19. CONVERSION OF FERTILITY RESTORATION OF THE SORGHUM IS1112C (A3) MALE-STERILE CYTOPLASM FROM TWO GENES TO ONE GENE.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The restoration of male fertility in sorghum lines carrying the IS1112C male-sterile cytoplasm requires complementary gametophytic action of two restoring alleles, Rf3 and Rf4, for individual gamete viability. An F1 heterozygous for the two restoring loci is expected to exhibit 25% viable pollen, a...

  20. Sexual harassment and health among male and female police officers.

    PubMed

    de Haas, Stans; Timmerman, Greetje; Höing, Mechtild

    2009-10-01

    The aims of this study were to investigate whether sexual harassment is related to mental and physical health of both men and women, and to explore the possible moderating effects of gender on the relation between sexual harassment and health. In addition, we investigated whether women were more often bothered by sexual harassment than men, and whether victims who report being bothered by the harassment experience more health problems compared to victims who did not feel bothered. A representative sample of 3,001 policemen and 1,295 policewomen in the Dutch police force filled out an Internet questionnaire. It appeared that women were more often bothered by sexual harassment than men, but gender did not moderate the relation between sexual harassment and mental and physical health. In addition, victims who felt bothered by the harassing behaviors reported more mental and physical health problems than victims who did not feel bothered. The distinction between bothered and nonbothered victims is important because appraisal is an essential aspect in the operationalization of sexual harassment. PMID:19839659

  1. Relationship Factors Associated with Gay Male Couples’ Concordance on Aspects of Their Sexual Agreements: Establishment, Type, and Adherence

    PubMed Central

    Mitchell, Jason W.; Harvey, S. Marie; Champeau, Donna; Moskowitz, David A.; Seal, David Wyatt

    2014-01-01

    Factors associated with gay male couples’ concordance on aspects of sexual agreements remain understudied. The present study examined which relationship factors, self-reports of UAI, and patterns of HIV testing may be associated with men who were concordant about having a sexual agreement, the same type of sexual agreement, and adhering to their sexual agreement with their main partner. Various recruitment strategies were used to collect dyadic data from 142 gay male couples. Concordance on aspects of sexual agreements varied within the sample. Results indicated that relationship satisfaction was significantly associated with couples who were concordant about having and adhering to their sexual agreement. Predictability and faith of trusting a partner, and value in one’s sexual agreement were also positively associated with couples’ adhering to their sexual agreement. More research is needed to better understand how relationship dynamics, including sexual agreements, affect HIV risk among gay male couples in the U.S. PMID:22012148

  2. Relationship factors associated with gay male couples' concordance on aspects of their sexual agreements: establishment, type, and adherence.

    PubMed

    Mitchell, Jason W; Harvey, S Marie; Champeau, Donna; Moskowitz, David A; Seal, David Wyatt

    2012-08-01

    Factors associated with gay male couples' concordance on aspects of sexual agreements remain understudied. The present study examined which relationship factors, self-reports of UAI, and patterns of HIV testing may be associated with men who were concordant about having a sexual agreement, the same type of sexual agreement, and adhering to their sexual agreement with their main partner. Various recruitment strategies were used to collect dyadic data from 142 gay male couples. Concordance on aspects of sexual agreements varied within the sample. Results indicated that relationship satisfaction was significantly associated with couples who were concordant about having and adhering to their sexual agreement. Predictability and faith of trusting a partner, and value in one's sexual agreement were also positively associated with couples' adhering to their sexual agreement. More research is needed to better understand how relationship dynamics, including sexual agreements, affect HIV risk among gay male couples in the U.S. PMID:22012148

  3. Immune activation affects chemical sexual ornaments of male Iberian wall lizards

    NASA Astrophysics Data System (ADS)

    López, Pilar; Gabirot, Marianne; Martín, José

    2009-01-01

    Many animals use chemical signals in sexual selection, but it is not clear how these sexual traits might have evolved to signal honestly male condition. It is possible that there is a trade-off between maintaining the immune system and the elaboration of ornaments. We experimentally challenged the immune system of male Iberian wall lizards, Podarcis hispanica, with a bacterial antigen (lipopolysaccharide), without pathogenic effects, to explore whether the immune activation affected chemical ornaments. Immune activation resulted in decreased proportions of a major chemical in femoral secretions (cholesta-5,7-dien-3-ol = provitamin D3) known to be selected in scent of males by females and which active form (vitamin D) has a variety of important effects on immune system function. This result suggests the existence of a potential trade-off between physiological regulation of the immune system and the allocation of essential nutrients (vitamins) to sexual chemical ornaments in male lizards.

  4. Development of Muscularity and Weight Concerns in Heterosexual and Sexual Minority Males

    PubMed Central

    Calzo, Jerel P.; Corliss, Heather L.; Blood, Emily A.; Field, Alison E.; Austin, S. Bryn

    2013-01-01

    Objective To examine the development of muscularity and weight concerns among heterosexual and sexual minority males in adolescence. Method Participants were 5,868 males from the Growing Up Today Study, a US prospective cohort spanning ages 9–25 years. Generalized estimating equations were used to test sexual orientation differences in the development of muscularity concerns, weight gain attempts, and weight and shape concern. Results Desire for bigger muscles increased slightly each year across adolescence (? =.10, 95% C.I.= .09, .11) regardless of sexual orientation, but gay and bisexual participants reported greater desire for toned muscles than completely and mostly heterosexual males (?=.39, 95% C.I.=.21, .57). Desire for toned muscles did not change with age. Attempts to gain weight increased three-fold across adolescence, with up to 30% reporting weight gain attempts by age 16. Although underweight males (the smallest weight status class) were most likely to attempt to gain weight, most of the observed weight gain attempts were by healthy (69%) and overweight/obese (27%) males, suggesting that most attempts were medically unnecessary and could lead to overweight. Sexual minority participants were 20% less likely to report weight gain attempts than completely heterosexual participants. Weight and shape concern increased with age, with gay and bisexual participants experiencing a significantly greater increase than heterosexual males. Conclusions Sexual orientation modifies the development and expression of male weight and muscularity concerns. The findings have implications for early interventions for the prevention of obesity and eating disorder risk in heterosexual and sexual minority males. PMID:23316852

  5. Male sexual signaling is defective in mutants of the apterous gene of Drosophila melanogaster

    Microsoft Academic Search

    John Ringo; Ruth Werczberger; Daniel Segal

    1992-01-01

    Theapterous (ap) gene ofDrosophila melanogaster exhibits extreme pleiotrophy: its functioning is essential for life, normal wing structure, juvenile hormone production, female fertility, and normal development of female sexual receptivity. Four mutantap alleles (ap4,ap56f,apc, andapblt) were characterized for three additional phenotypes: male mating success, courtship behavior, and immature male sex appeal (the ability of males to stimulate homosexual cortship). Mating success

  6. Sexual dimorphism and male mating success in the tentacled blenny, Parablennius tentacularis (Teleostei: Blenniidae)

    Microsoft Academic Search

    Eva Giacomello; Maria B. Rasotto

    2005-01-01

    Although external sexually dimorphic traits are commonly found in males of combtooth blenny species, little is known about\\u000a the benefit they can convey to male mating success. Indeed, while female preferences for large males have been demonstrated\\u000a in some species, the possible role played by dimorphic ornaments has been neglected. We now report on the tentacled blenny,\\u000a Parablennius tentacularis, a

  7. Male satin bowerbirds ( Ptilonorhynchus violaceus ) compensate for sexual signal loss by enhancing multiple display features

    Microsoft Academic Search

    Benjamin D. Bravery; Anne W. Goldizen

    2007-01-01

    Numerous studies have focussed on the relationship between female choice and the multiple exaggerated sexual traits of males.\\u000a However, little is known about the ability of males to actively enhance specific components of their display in response to\\u000a the loss of one component. We investigated the capacity of male satin bowerbirds (Ptilonorhynchus violaceus) to respond to the loss of one

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

    PubMed

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

    2012-10-01

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

  9. Sexual selection for small size in male mosquitofish (Gambusia holbrooki)

    PubMed Central

    Pilastro, A.; Giacomello, E.; Bisazza, A.

    1997-01-01

    In many poeciliid fishes, large males which court females coexist with small males which sneak-copulate. It is unclear whether these two tactics represent two evolutionarily stable strategies or if sneaking is a conditional strategy adopted by small, unattractive males. We studied the success of sneaky copulation by looking for sperm in the gonoduct of females after they were kept for 48 h with a male. A logistic regression analysis showed that the probability of a female being inseminated increased with female length and decreased with male length. The length of the male relative to that of the female was the best predictor of success. This result was confirmed using virgin females, thereby excluding any possible confounding effect due to the release of sperm from previous copulations. Sperm counts suggested that large males do not compensate for their reduced copulatory success by releasing larger sperm numbers. Behavioural data indicate that the advantages to small males are twofold: they have a greater chance to approach females from behind without being detected, and manoeuvre better when inserting the gonopodium into the female's gonoduct. The selective advantage of small size might explain male dwarfism in poeciliids. Our results also suggest that small males adopting the sneaky tactic may be as successful as large males adopting courtship, and that alternative mating strategies may be maintained by negative density-dependent selection.

  10. Effect of sublingual medication of sildenafil citrate/ apomorphine on sexual behaviour of male rats.

    PubMed

    Huang, X; Xiong, C; Zhou, J; Shen, J

    2009-04-01

    The study investigated the combined effect of sublingually administered sildenafil (SN) and apomorphine (APO SL) on the sexual behaviour of male rats. Male Sprague-Dawley rats (50) were divided into five groups (10 rats per each group): blank control, sildenafil group and SN plus APO SL high dosage, medium dosage and low dosage group. After sublingual administration of the agents (control and SN plus APO SL) and a sole dosage of sildenafil (stomach irrigation), the rats were mated with female counterparts in pairs, and the latent period of chasing, the frequency of chasing in 60 min, the latent period of mounting and the frequency of mounting in 60 min were recorded. The lower dosage of SN plus APO SL exerted a stronger influence on the sexual activities in male rats than did the higher sole dosage of sildenafil. Identification of common neurochemical and neuroanatomical substrates of sexual responding between animals and humans suggests that the evolution of sexual behaviour has been highly conserved and indicates that animal models of human sexual response can be used successfully as pre-clinical tools. So sublingual medication of SN combined with APO SL may be at least a support inference about male sexual libido. PMID:19260841

  11. Identification of aberrant chromosomes on the basis of morphometry of synaptonemal complexes in the sterile male mouse

    SciTech Connect

    Kalinskaya, E.I.; Chepyzhov, V.V.; Bogdanov, Yu.F.

    1989-01-01

    The results of an investigation of the synaptonemal complexes (SCs) of spermatocytes of sterile males of the house mouse from the progeny of parents subjected to the action of a mutagen are presented in this study. A nonreciprocal translocation was readily identified by the configuration of the SCs. The translocation was observed at pachytene in 100% of cells; at diakinesis-metaphase I, in 58% of cells. A different pattern of association of the X chromosome with the rearrangement region was found in pachytene spermatocytes. Computer analysis of the relative lengths of the synaptonemal complex during the pachytene stage permitted the determination that the translocation took place from the 4th autosome to the 16th. The translocated segment was 66-75% of chromosome 4. In chromosome 16 the point of rupture is close to the distal end, and it was not possible to find the broken-off telomeric fragment of this chromosome in the male under study.

  12. The Arabidopsis male-sterile mutant, opr3, lacks the 12-oxophytodienoic acid reductase required for jasmonate synthesis

    PubMed Central

    Stintzi, Annick; Browse, John

    2000-01-01

    Jasmonic acid (JA) and its precursor 12-oxophytodienoic acid (OPDA) act as plant growth regulators and mediate responses to environmental cues. To investigate the role of these oxylipins in anther and pollen development, we characterized a T-DNA-tagged, male-sterile mutant of Arabidopsis, opr3. The opr3 mutant plants are sterile but can be rendered fertile by exogenous JA but not by OPDA. Cloning of the mutant locus indicates that it encodes an isozyme of 12-oxophytodienoate reductase, designated OPR3. All of the defects in opr3 are alleviated by transformation of the mutant with an OPR3 cDNA. Our results indicate that JA and not OPDA is the signaling molecule that induces and coordinates the elongation of the anther filament, the opening of the stomium at anthesis, and the production of viable pollen. Just as importantly, our data demonstrate that OPR3 is the only isoform of OPR capable of reducing the correct stereoisomer of OPDA to produce JA required for male gametophyte development. PMID:10973494

  13. Characterisation of a cytoplasmic male-sterile hybrid line between Lycopersicon peruvianum Mill. ×Lycopersicon pennellii Corr. and its crosses with cultivated tomato

    Microsoft Academic Search

    M. Petrova; Z. Vulkova; N. Gorinova; S. Izhar; N. Firon; J.-M. Jacquemin; A. Atanassov; P. Stoeva

    1999-01-01

    The cytoplasmic male-sterile (CMS) line CMS-pennellii (BC10P2\\u000a \\u000a L. peruvianumL. pennellii) and its complex hybrids with L. esculentum were studied. The established sterility was classified as the sporogenous type. As a result of the interaction of the genome\\u000a of L. pennellii and the cytoplasm of L. peruvianum clear changes were established in the profiles of malic enzyme and esterase. Restriction fragment

  14. Adult circumcision and male sexual health: a retrospective analysis.

    PubMed

    Dias, J; Freitas, R; Amorim, R; Espiridião, P; Xambre, L; Ferraz, L

    2014-06-01

    We aimed to evaluate possible associations of circumcision with several sexual dysfunctions and to identify predictors for the development of these outcomes post-operatively. Telephone surveys about sexual habits and dysfunctions before and after intervention were conducted post-operatively to patients that underwent circumcision in Centro Hospitalar Vila Nova de Gaia/Espinho during 2011. McNemar test was used for a matched-pairs analysis of pre- and post-operative data. Odds ratios, adjusted in a multivariate analysis, explored predictors of de novo sexual dysfunctions after circumcision. With intervention, there was an increase in frequency of erectile dysfunction (9.7% versus 25.8%, P = 0.002) and delayed orgasm (11.3% versus 48.4%, P < 0.001), and a significant symptomatic improvement in patients with pain with intercourse (50.0% versus 6.5%, P < 0.001). Significant predictors for de novo erectile dysfunction were diabetes mellitus (OR 9.81, P = 0.048) and lack of sexual desire (OR 8.76, P = 0.028). Less than three sex partners (OR 7.04, P = 0.007) and low sexual desire (OR 7.49, P = 0.029) were significant predictors for de novo delayed orgasm. PMID:23600924

  15. A Pilot Study on Tamoxifen Sexual Side Effects and Hand Preference in Male Breast Cancer.

    PubMed

    Motofei, Ion G; Rowland, David L; Popa, Florian; Bratucu, Eugen; Straja, Dan; Manea, Mirela; Georgescu, Simona R; Paunica, Stana; Bratucu, Mircea; Balalau, Cristian; Constantin, Vlad D

    2015-08-01

    Recent clinical and imaging studies suggest that sex hormones modulate sexuality according to a psychophysiologic process of lateralization of the brain, with androgens playing a greater role in sexual functioning of left hemibrain/right handedness and estrogens possibly for right hemibrain/left handedness. Based on this perspective, the current study attempted to specify the relationship between hand preference, estrogens, and sexual function in subjects with male breast cancer, taking into account the sexual side effects of tamoxifen as the agent for inhibiting estrogen action. Twenty-eight Romanian men-17 right-handed and 11 left-handed-undergoing treatment with tamoxifen for male breast cancer participated in this study. These men were assessed both prior to and during tamoxifen treatment using the International Index of Erectile Function, a standardized instrument used for the evaluation of various aspects of sexual functioning, including erectile function (EF), orgasmic function (OF), sexual desire (SD), and overall functioning (OF). A main effect for handedness was found on EF, OF, SD, and OS scales, with right-handed men showing higher functioning than left-handed men. Regarding interaction effects, the left-handed group of men showed greater decreased sexual functioning during tamoxifen (on three subscales: OF, SD, OS) compared to right-handed men. Further research should be conducted in order to support and refine this potential lateralized process of sexual neuromodulation within the brain. PMID:26108899

  16. Sociosexual attitudes and dyadic sexual desire independently predict women's preferences for male vocal masculinity.

    PubMed

    O'Connor, Jillian J M; Jones, Benedict C; Fraccaro, Paul J; Tigue, Cara C; Pisanski, Katarzyna; Feinberg, David R

    2014-10-01

    Research suggests that the desire to behave sexually with a partner (dyadic sexual desire) may reflect desire for intimacy whereas solitary sexual desire may reflect pleasure seeking motivations more generally. Because direct reproductive success can only be increased with a sexual partner, we tested whether dyadic sexual desire was a better predictor of women's preferences for lower pitched men's voices (a marker of relatively high reproductive success) than was solitary sexual desire. In Study 1, women (N = 95) with higher dyadic sexual desire scores on the Sexual Desire Inventory-2 preferred masculinized male voices more than did women with lower dyadic sexual desire scores. We did not find a significant relationship between women's vocal masculinity preferences and their solitary sexual desire scores. In Study 2, we tested whether the relationship between voice preferences and dyadic sexual desire scores was related to differences in sociosexual orientation. Women (N = 80) with more positive attitudes towards uncommitted sex had stronger vocal masculinity preferences regardless of whether men's attractiveness was judged for short-term or long-term relationships. Independent of the effect of sociosexual attitudes, dyadic sexual desire positively predicted women's masculinity preferences when assessing men's attractiveness for short-term but not long-term relationships. These effects were independent of women's own relationship status and hormonal contraceptive use. Our results provide further evidence that women's mate preferences may independently reflect individual differences in both sexual desire and openness to short-term relationships, potentially with the ultimate function of maximizing the fitness benefits of women's mate choices. PMID:24830906

  17. Contextualization of Physical and Sexual Assault in Male Prisons: Incidents and Their Aftermath

    PubMed Central

    Wolff, Nancy; Shi, Jing

    2010-01-01

    Physical and sexual assault are part of the prison experience. Approximately 21% of male inmates are physically assaulted during a 6-month period. Sexual assault is estimated at between 2% and 5%. Although prevalence evidence is growing, less is known about circumstances surrounding and resulting from these incidents. This article presents an analysis of approximately 2,200 physical and 200 sexual victimizations reported by a random sample of 6,964 male inmates. Physical injury occurred in 40% of physical assaults and 70% of sexual assaults between inmates and in 50% of assaults perpetrated by staff. Emotional reactions to assaults were experienced by virtually all victims. Context information is vital in the development and implementation of prevention and therapeutic interventions. PMID:19477812

  18. Pornography and the Male Sexual Script: An Analysis of Consumption and Sexual Relations.

    PubMed

    Sun, Chyng; Bridges, Ana; Johnason, Jennifer; Ezzell, Matt

    2014-12-01

    Pornography has become a primary source of sexual education. At the same time, mainstream commercial pornography has coalesced around a relatively homogenous script involving violence and female degradation. Yet, little work has been done exploring the associations between pornography and dyadic sexual encounters: What role does pornography play inside real-world sexual encounters between a man and a woman? Cognitive script theory argues media scripts create a readily accessible heuristic model for decision-making. The more a user watches a particular media script, the more embedded those codes of behavior become in their worldview and the more likely they are to use those scripts to act upon real life experiences. We argue pornography creates a sexual script that then guides sexual experiences. To test this, we surveyed 487 college men (ages 18-29 years) in the United States to compare their rate of pornography use with sexual preferences and concerns. Results showed the more pornography a man watches, the more likely he was to use it during sex, request particular pornographic sex acts of his partner, deliberately conjure images of pornography during sex to maintain arousal, and have concerns over his own sexual performance and body image. Further, higher pornography use was negatively associated with enjoying sexually intimate behaviors with a partner. We conclude that pornography provides a powerful heuristic model which is implicated in men's expectations and behaviors during sexual encounters. PMID:25466233

  19. Male-Specific Fruitless Isoforms Target Neurodevelopmental Genes to Specify a Sexually Dimorphic Nervous System

    PubMed Central

    Neville, Megan C.; Nojima, Tetsuya; Ashley, Elizabeth; Parker, Darren J.; Walker, John; Southall, Tony; Van de Sande, Bram; Marques, Ana C.; Fischer, Bettina; Brand, Andrea H.; Russell, Steven; Ritchie, Michael G.; Aerts, Stein; Goodwin, Stephen F.

    2014-01-01

    Summary Background In Drosophila, male courtship behavior is regulated in large part by the gene fruitless (fru). fru encodes a set of putative transcription factors that promote male sexual behavior by controlling the development of sexually dimorphic neuronal circuitry. Little is known about how Fru proteins function at the level of transcriptional regulation or the role that isoform diversity plays in the formation of a male-specific nervous system. Results To characterize the roles of sex-specific Fru isoforms in specifying male behavior, we generated novel isoform-specific mutants and used a genomic approach to identify direct Fru isoform targets during development. We demonstrate that all Fru isoforms directly target genes involved in the development of the nervous system, with individual isoforms exhibiting unique binding specificities. We observe that fru behavioral phenotypes are specified by either a single isoform or a combination of isoforms. Finally, we illustrate the utility of these data for the identification of novel sexually dimorphic genomic enhancers and novel downstream regulators of male sexual behavior. Conclusions These findings suggest that Fru isoform diversity facilitates both redundancy and specificity in gene expression, and that the regulation of neuronal developmental genes may be the most ancient and conserved role of fru in the specification of a male-specific nervous system. PMID:24440396

  20. Onset, persistence, and versatility of offending among adult males convicted of sexual offenses against children.

    PubMed

    Smallbone, Stephen W; Wortley, Richard K

    2004-10-01

    Official sexual and nonsexual offense histories and confidential self-report data on sexual offending were obtained on 207 adult males serving sentences for sexual offenses against children (98 intrafamilial, 72 extrafamilial, and 37 mixed-type offenders). The mean self-reported age when offenders first had sexual contact with a child was 32.2 years (median = 31 years; range = 10-63 years). The mean age at first conviction for any offense was 30.5 years (median = 27 years, range = 12-66 years), and the mean age at first conviction for a sexual offense was 37.3 years (median = 37 years; range = 15-76 years). Sixty-nine percent (n = 143) of the combined sample had at least one previous conviction, and 80% of these (n = 114) had first been convicted for a nonsexual offense. ANCOVA revealed a systematic pattern of onset with first convictions for any offense preceding first sexual contact with a child. Taken together, results indicate that, in general, adult child molesters (a) begin sexual offending in their 30s, (b) have already become involved in nonsexual crime by the time they first have sexual contact with a child, (c) are criminally versatile, and (d) vary considerably in their persistence with respect to both sexual and nonsexual offending. PMID:15560412

  1. Androgens and Male Sexual Function: A Review of Human Studies

    ERIC Educational Resources Information Center

    Schiavi, Raul C.; White, Daniel

    1976-01-01

    The scope of this article is a review and brief discussion of recently gathered information on androgens and sexual behavior in men. Current pharmacological research does not furnish specific evidence that administration of androgens or preprations that stimulate the secretion of endogenous androgens have beneficial effects on functional…

  2. ORIGINAL PAPER Males, but not females, contribute to sexual isolation

    E-print Network

    Gabor, Caitlin - Department of Biology, Texas State University

    sexual isolation via conspecific mate preference between Gambusia affinis and G. geiseri in both sexes of Gambusia Celeste M. Espinedo · Caitlin R. Gabor · Andrea S. Aspbury Received: 6 May 2009 / Accepted: 2 reproductive isolation between the sexes in G. affinis and G. geiseri, but symmetrical species isolation

  3. Male sexual arousal with repeated exposure to erotic stimuli

    Microsoft Academic Search

    Elise Julien; Ray Over

    1984-01-01

    Twenty-four men were exposed to erotic material of matched content across five sessions, each separated by 24 hours or more. The stimulation within a session consisted of eight 12-minute episodes depicting heterosexual activities. Both penile circumference and subjective sexual arousal varied significantly across the segments within a session. However, neither response measure showed habituation across sessions. Participation in the study

  4. Behavior patterns and sexual identity of bisexual males

    Microsoft Academic Search

    Janet Lever; David E. Kanouse; William H. Rogers; Sally Carson; Rosanna Hertz

    1992-01-01

    Bisexuality may be measured in terms of bisexual behavior or bisexual self?identity. The relationship between the two is poorly understood. Data from a 1982 survey of readers of Playboy magazine are used to examine the identity and behavior of 6,982 men who acknowledged adult sexual experiences with both men and women. Of these, 29 percent described themselves as bisexual, 2

  5. Male Sexual Polymorphism, Alternative Reproductive Tactics, and Androgens in

    E-print Network

    "sneaker" fertilizations (e.g., sneaker and satellite males). In combtooth blennies (Blenniidae) the co. Interestingly, while in the peacock blenny the alternative male morph adopts a sneaker tactic, in the rock and that the admin- istration of sex steroids should be effective in promoting the switch from the parasitic

  6. Sexual Well-Being in Adult Male Patients with Congenital Adrenal Hyperplasia

    PubMed Central

    Dudzi?ska, Bogna; Leubner, Jonas; Ventz, Manfred; Quinkler, Marcus

    2014-01-01

    Introduction. Men with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency show impaired fecundity due to testicular adrenal rest tumors and/or suppression of the gonadal axis. Sexual well-being might be an additional factor; however, no data exists. Patients and Methods. Prospective longitudinal monocentric study included 20 male CAH patients (14 salt wasting, 6 simple virilizing; age 18–49?yr). Clinical assessment, testicular ultrasound, biochemical and hormonal parameters, three validated self-assessment questionnaires (SF-36, GBB-24, and HADS), and male Brief Sexual Function Inventory (BSFI) were analyzed at baseline and after two years. Results. Basal LH and testosterone levels suggested normal testicular function. LH and FSH responses to GnRH were more pronounced in patients with a good therapy control according to androstenedione/testosterone ratio < 0.2. This group had significant higher percentage of patients on dexamethasone medication. GBB-24, HADS, and SF-36 showed impaired z-scores and no changes at follow-up. BSFI revealed impairments in dimensions “sexual drive,” “erections,” and “ejaculations,” whereas “problem assessment” and “overall satisfaction” revealed normal z-scores. Androstenedione levels correlated (P = 0.036) inversely with z-scores for “sexual drive” with higher levels associated with impaired “sexual drive.” Conclusion. Male CAH patients showed a partly impaired sexual well-being which might be an additional factor for reduced fecundity. PMID:24672547

  7. Varieties of male-sexual-identity development in clinical practice: a neuropsychoanalytic model.

    PubMed

    Stortelder, Frans

    2014-01-01

    Variations of sexual identity development are present in all cultures, as well as in many animal species. Freud - founding father of psychoanalysis - believed that all men have an inherited, bisexual disposition, and that many varieties of love and desire are experienced as alternative pathways to intimacy. In the neuropsychoanalytic model, psychic development starts with the constitutional self. The constitutional self is comprised of the neurobiological factors which contribute to sexual identity development. These neurobiological factors are focused on biphasic sexual organization in the prenatal phase, based on variations in genes, sex hormones, and brain circuits. This psychosocial construction of sexual identity is determined through contingent mirroring by the parents and peers of the constitutional self. The development of the self-or personal identity-is linked with the development of sexual identity, gender-role identity, and procreative identity. Incongruent mirroring of the constitutional self causes alienation in the development of the self. Such alienation can be treated within the psychoanalytic relationship. This article presents a contemporary, neuropsychoanalytic, developmental theory of male-sexual identity relating to varieties in male-sexual-identity development, with implications for psychoanalytic treatment, and is illustrated with three vignettes from clinical practice. PMID:25566168

  8. Varieties of male-sexual-identity development in clinical practice: a neuropsychoanalytic model

    PubMed Central

    Stortelder, Frans

    2014-01-01

    Variations of sexual identity development are present in all cultures, as well as in many animal species. Freud – founding father of psychoanalysis – believed that all men have an inherited, bisexual disposition, and that many varieties of love and desire are experienced as alternative pathways to intimacy. In the neuropsychoanalytic model, psychic development starts with the constitutional self. The constitutional self is comprised of the neurobiological factors which contribute to sexual identity development. These neurobiological factors are focused on biphasic sexual organization in the prenatal phase, based on variations in genes, sex hormones, and brain circuits. This psychosocial construction of sexual identity is determined through contingent mirroring by the parents and peers of the constitutional self. The development of the self—or personal identity—is linked with the development of sexual identity, gender-role identity, and procreative identity. Incongruent mirroring of the constitutional self causes alienation in the development of the self. Such alienation can be treated within the psychoanalytic relationship. This article presents a contemporary, neuropsychoanalytic, developmental theory of male-sexual identity relating to varieties in male-sexual-identity development, with implications for psychoanalytic treatment, and is illustrated with three vignettes from clinical practice. PMID:25566168

  9. Childhood Sexual Abuse in Males and Subsequent Risky Sexual Behavior: A Potential Alcohol-Use Pathway

    ERIC Educational Resources Information Center

    Schraufnagel, Trevor J.; Davis, Kelly Cue; George, William H.; Norris, Jeanette

    2010-01-01

    Objective: Childhood sexual abuse (CSA) among boys has been associated with a variety of subsequent maladaptive behaviors. This study explored a potential connection between CSA and an increased likelihood of risky sexual behavior in adulthood. Further, the study examined whether or not alcohol use may contribute to this relationship. Method: As…

  10. Without women: Masculinities, gay male sexual culture and sexual behaviors in Miami, Florida

    Microsoft Academic Search

    Steven Peter Kurtz

    1999-01-01

    Recent studies have reported alarmingly high rates of HIV infection and risky sexual behaviors among gay men in Miami, Florida. Previous research has suggested that the risky sexual behaviors of many gay men reflect the pursuit of intimacy and love, and that barriers to intimate relationships among gay men may stem from traditional masculinity norms. This dissertation examines the meanings

  11. The psychological impact of sexual abuse: content analysis of interviews with male survivors.

    PubMed

    Lisak, D

    1994-10-01

    Autobiographical interviews with 26 adult male survivors of childhood sexual abuse were audiotaped, transcribed verbatim and content analyzed to identify common psychological themes. Approximately equal numbers of men were abused by male and female perpetrators, almost half came from disrupted or violent homes and a majority had a history of substance abuse. Fifteen psychological themes were identified: Anger, Betrayal, Fear, Homosexuality Issues, Helplessness, Isolation and Alienation, Legitimacy, Loss, Masculinity Issues, Negative Childhood Peer Relations, Negative Schemas about People, Negative Schemas about the Self, Problems with Sexuality, Self Blame/Guilt and Shame/Humiliation. The themes are discussed and illustrated with examples drawn from the transcripts. PMID:7820347

  12. Cryptic Sex within Male?Sterile Polyploid Populations of the Easter Daisy, Townsendia hookeri

    Microsoft Academic Search

    Stacey Lee Thompson; Gina Choe; Kermit Ritland; Jeannette Whittony

    2008-01-01

    After a transition from sexuality to asexuality, the evolutionary dynamics in apomictic lineages will largely depend on the frequency of recombination. We evaluated the presence and extent of asexuality and recom- bination within populations of the Easter daisy, Townsendia hookeri, from the Yukon Territory, Canada. Amplified fragment-length polymorphism (AFLP) fingerprints were used to genotype 78 individuals from four populations. Multilocus

  13. Patterns of male sterility in a grasshopper hybrid zone imply accumulation of hybrid incompatibilities without selection

    Microsoft Academic Search

    David M. Shuker; Karen Underwood; Tania M. King; Roger K. Butlin

    2005-01-01

    It is now widely accepted that post-zygotic reproductive isolation is the result of negative epistatic interactions between derived alleles fixed independently at different loci in diverging populations (the Dobzhansky-Muller model). What is less clear is the nature of the loci involved and whether the derived alleles increase in frequency through genetic drift, or as a result of natural or sexual

  14. Blame toward male rape victims in a hypothetical sexual assault as a function of victim sexuality and degree of resistance.

    PubMed

    Davies, Michelle; Rogers, Paul; Bates, Jo-Anne

    2008-01-01

    This study investigates the impact of victim sexual orientation, the degree of victim physical resistance, and respondent gender on attributions of blame and assault severity in a hypothetical case of stranger-perpetrated male rape. One hundred eighty-three participants read a scenario depicting a rape in which the victim's sexuality and degree of resistance were both varied between-subjects before completing 12 blame attribution items. Overall, findings suggest that male respondents were less pro-victim than were females. While women generally attributed little victim blame and considered the assault very severe regardless of condition, men were influenced by both factors. Specifically, although men considered the assault severe, they blamed a gay victim more when he fought back against his attacker but, conversely, blamed a heterosexual victim when he did not fight back. Results are discussed in relation to homophobia and judgments about victim resistance during rape. Implications for treatment services are also considered. PMID:19042285

  15. The association between the fraternal birth order effect in male homosexuality and other markers of human sexual orientation

    PubMed Central

    Rahman, Qazi

    2005-01-01

    Later fraternal birth order (FBO) is a well-established correlate of homosexuality in human males and may implicate a maternal immunization response in the feminization of male sexuality. This has led to the suggestion that FBO may relate to other markers of male sexual orientation which are robustly sexually dimorphic. If so, among homosexual males the number of older brothers should strongly correlate with traits such as spatial ability and psychological gender, indicative of greater behavioural feminization, compared to heterosexual males. The present study failed to find significant associations between number of older brothers and these traits. PMID:17148215

  16. Part II: differences between sexually victimized and nonsexually victimized male adolescent sexual abusers and delinquent youth: further group comparisons of developmental antecedents and behavioral challenges.

    PubMed

    Leibowitz, George S; Burton, David L; Howard, Alan

    2012-01-01

    In a recent paper published in the Journal of Child Sexual Abuse, we assessed the differences between sexually victimized and nonsexually victimized male adolescent sexual abusers ( Burton, Duty, & Leibowitz, 2011 ). We found that the sexually victimized group had more severe developmental antecedents (e.g., trauma and early exposure to pornography) and behavioral difficulties (sexual aggression, arousal, pornography use, and nonsexual offenses). The present study compares sexually victimized and nonsexually victimized adolescent sexual abusers with a group of nonsexually victimized delinquent youth. Findings included that delinquent youth had fewer behavioral and developmental problems than the comparison groups. In addition, sexually victimized sexual abusers had the highest mean scores on trauma and personality measures. Implications for research and treatment are offered. PMID:22574846

  17. Social and psychological perspectives on voluntary sterilization: a review.

    PubMed

    Philliber, S G; Philliber, W W

    1985-01-01

    This paper reviews social science research on the antecedents and consequences of voluntary sterilization. The major conclusions are that socioeconomic status has little impact on the decision to be sterilized and that sterilizations are rare among those without sons and among male non-whites. Significant others are important sources of encouragement and information, and good marital relations increase the likelihood of having the procedure performed. Most acceptors experience no change in sexual activity, quality of marital relationships, or work-related behavior, and few regret their choice. Negative consequences are more likely among those in India, those coerced into having a sterilization, those who did not understand the consequences of the procedure, those with health complications after sterilization, and those couples who have unstable marriages or who disagree about sterilization. PMID:3983979

  18. Male sexual arousal across five modes of erotic stimulation

    Microsoft Academic Search

    Elise Julien; Ray Over

    1988-01-01

    Penile circumference changes and subjective sexual arousal were recorded when erotic material depicting the same sequence of events was experienced in five different modes: film, slides, spoken-text, written-text, and fantasy. Twenty-four men were tested within a repeated-measures design, with the order of presentation of modes counterbalanced across subjects. Sessions were separated by 24 hr or more. The highest levels of

  19. Olfactory threshold for bourgeonal and sexual desire in young adult males.

    PubMed

    Ottaviano, Giancarlo; Marioni, Gino; Frasson, Giuliana; Zuccarello, Daniela; Marchese-Ragona, Rosario; Staffieri, Claudia; Nardello, Ennio; Frigo, Anna Chiara; Foresta, Carlo; Staffieri, Alberto

    2015-05-01

    Olfactory receptors were found to be expressed also in human sperm giving rise to the hypothesis that they might play a role in fertility and sexual behavior. For instance, bourgeonal was demonstrated to be an agonist of sperm cells olfactory receptor, OR1D2. OR1D2 has been found to be expressed in human olfactory epithelium and to play a critical role in human sperm chemotaxis. Recent preliminary evidence showed that olfaction sensitivity (determined by n-butanol olfactory threshold) and sexual desire were associated in young adult males. It is reasonable to hypothesize that bourgeonal olfactory threshold could be related with human sexual behavior and desire. In 37 healthy young adult male volunteers (age range 20-36 years), the bourgeonal odor threshold and the intensity of sexual desire [the latter using the International Index of Erectile Function (IIEF) scale] were examined. In addition, samples of DNA were collected. Allele and genotype frequency of the OR1D2 single nucleotide polymorphisms (SNPs) were then evaluated in order to study the relationship between sexual desire and OR1D2 SNPs expression. The olfactory threshold was categorized as <10, 10?threshold<15, 15?threshold<20, ?20. IIEF 1 and IIEF 2 scores were significantly associated. IIEF1 scores, but not IIEF2 scores were significantly associated with olfactory threshold. No statistically significant associations were found neither between genotypes frequency and sexual desire (IIEF1 and IIEF2), nor between genotypes frequency and olfactory threshold. Hypothesizing for the first time the relationship between bourgeonal olfactory sensitivity and sexual desire in a group of young adult males, the present study found a significant association between lower olfactory threshold for bourgeonal and stronger sexual desire, in terms of IIEF1. PMID:25665864

  20. Comparative proteomics analysis reveals the mechanism of fertility alternation of thermosensitive genic male sterile rice lines under low temperature inducement.

    PubMed

    Song, Liru; Liu, Zhongqi; Tong, Jianhua; Xiao, Langtao; Ma, Hao; Zhang, Haiqing

    2015-06-01

    Thermosensitive genic male sterile (TGMS) rice line has made great economical contributions in rice production. However, the fertility of TGMS rice line during hybrid seed production is frequently influenced by low temperature, thus leading to its fertility/sterility alteration and hybrid seed production failure. To understand the mechanism of fertility alternation under low temperature inducement, the extracted proteins from young panicles of two TGMS rice lines at the fertility alternation sensitivity stage were analyzed by 2DE. Eighty-three protein spots were found to be significantly changed in abundance, and identified by MALDI-TOF-TOF MS. The identified proteins were involved in 16 metabolic pathways and cellular processes. The young panicles of TGMS rice line Zhu 1S possessed the lower ROS-scavenging, indole-3-acetic acid level, soluble protein, and sugar contents as well as the faster anther wall disintegration than those of TGMS rice line Zhun S. All these major differences might result in that the former is more stable in fertility than the latter. Based on the majority of the 83 identified proteins, together with microstructural, physiological, and biochemical results, a possible fertile alteration mechanism in the young panicles of TGMS rice line under low temperature inducement was proposed. Such a result will help us in breeding TGMS rice lines and production of hybrid seed. PMID:25641954

  1. RNase Z(S1) processes UbL40 mRNAs and controls thermosensitive genic male sterility in rice.

    PubMed

    Zhou, Hai; Zhou, Ming; Yang, Yuanzhu; Li, Jing; Zhu, Liya; Jiang, Dagang; Dong, Jingfang; Liu, Qinjian; Gu, Lianfeng; Zhou, Lingyan; Feng, Mingji; Qin, Peng; Hu, Xiaochun; Song, Chengli; Shi, Jinfeng; Song, Xianwei; Ni, Erdong; Wu, Xiaojin; Deng, Qiyun; Liu, Zhenlan; Chen, Mingsheng; Liu, Yao-Guang; Cao, Xiaofeng; Zhuang, Chuxiong

    2014-01-01

    Thermosensitive genic male-sterile (TGMS) lines, which are male-sterile at restrictive (high) temperatures but male-fertile at permissive (low) temperatures, have been widely used in breeding two-line hybrid rice (Oryza sativa L.). Here we find that mutation of thermosensitive genic male sterile 5 (tms5) in rice causes the TGMS trait through a loss of RNase Z(S1) function. We show that RNase Z(S1) processes the mRNAs of three ubiquitin fusion ribosomal protein L40 (UbL40) genes into multiple fragments in vitro and in vivo. In tms5 mutants, high temperature results in increased levels of UbL40 mRNAs. Overaccumulation of UbL40 mRNAs causes defective pollen production and male sterility. Our results uncover a novel mechanism of RNase Z(S1)-mediated UbL40 mRNA regulation and shows that loss of this regulation produces TGMS in rice, a finding with potential applications in hybrid crop breeding. PMID:25208476

  2. Exploring the Overlap in Male Juvenile Sexual Offending and General Delinquency: Trauma, Alcohol Use, and Masculine Beliefs

    ERIC Educational Resources Information Center

    Brown, Adam; Burton, David L.

    2010-01-01

    Despite Burton and Meezan's (2004) finding that sexually aggressive youth are three to four times more likely to recidivate nonsexually than sexually, there is little to no research to date that explores this overlap in criminality. With a sample of 290 male sexually violent adjudicated and incarcerated youth, this study was able to successfully…

  3. Social Norms and Beliefs Regarding Sexual Risk and Pregnancy Involvement among Adolescent Males Treated for Dating Violence Perpetration

    PubMed Central

    Decker, Michele R.; Reed, Elizabeth; Rothman, Emily F.; Hathaway, Jeanne E.; Raj, Anita; Miller, Elizabeth

    2006-01-01

    The present study explored perceived sexual norms and behaviors related to sexual risk and pregnancy involvement among adolescent males (ages 13 to 20) participating in programs for perpetrators of dating violence. The purpose of this study was to generate hypotheses regarding the contexts and mechanisms underlying the intersection of adolescent dating violence, sexual risk and pregnancy. Six focus groups were conducted (N = 34 participants). A number of major themes emerged: 1) male norm of multiple partnering, 2) perceived gain of male social status from claims of sexual activity, 3) perception that rape is uncommon combined with belief that girls claiming to be raped are liars, 4) perception that men rationalize rapes to avoid responsibility, 5) condom non-use in the context of rape and sex involving substance use, 6) beliefs that girls lie and manipulate boys in order to become pregnant and trap them into relationships, and 7) male avoidance of responsibility and negative responses to pregnancy. The combination of peer-supported norms of male multiple partnering and adversarial sexual beliefs appear to support increased male sexual risk, lack of accountability for sexual risk, and rationalization of rape and negative responses to pregnancy. Further research focused on the context of male sexual risk and abusive relationship behaviors is needed to inform intervention with young men to promote sexual health and prevent rape, dating violence, and adolescent pregnancy. PMID:16845498

  4. [The cDNA-AFLP differential display in developing anthers between cotton male sterile and fertile line of "Dong A"].

    PubMed

    Hou, Lei; Xiao, Yue-Hua; Li, Xian-Bi; Wang, Wen-Feng; Luo, Xiao-Ying; Pei, Yan

    2002-04-01

    cDNA-AFLP, an effective method for mRNA differential display, was employed to compare the gene expression in developing anthers between the male sterile and fertile plants of cotton (Gossypium hirsutum L.) cultivar, Dong A. In the micro-spore stage, there were more differential bands of cDNA-AFLP than that in the meio-phase stage. Among 64 differential fragments produced by cDNA-AFLP, three were randomly selected for further analysis. RNA dot blotting showed that the GHA27 transcript was expressed mainly in floral tissues; on the other hand, the GHA28 and GHA47 transcripts were present specifically in anther. BLAST analysis demonstrated that GHA27 was highly similar to the plant ADP-ribosylation factor genes, while GHA28 and GHA27 were shown no significant similar to any sequences in the available databases. PMID:11985272

  5. Influence of Griffonia simplicifolia on male sexual behavior in rats: Behavioral and neurochemical study

    Microsoft Academic Search

    G. Carnevale; V. Di Viesti; M. Zavatti; A. Benelli; P. Zanoli

    2011-01-01

    The seeds of Griffonia simplicifolia Baill. are rich in 5-HTP (5-hydroxytryptophan), a direct precursor of the neurotransmitter serotonin. In the present study we investigated the influence of the plant extract on male sexual behavior. The seed extract was orally administered to Sprague-Dawley male rats at three dose levels (25, 50 and 100mg\\/kg) both acutely and subchronically (daily for 9days). Mating

  6. Women's sexual and emotional responses to male- and female-produced erotica

    Microsoft Academic Search

    Ellen Laan; Walter Everaerd; Gerdy van Bellen; Gerrit Hanewald

    1994-01-01

    Whether erotic films made by women are more arousing for women than erotic films made by men was studied. Forty-seven subjects were exposed to both a woman-made, female-initiated, and female-centered, erotic film excerpt and a man-made, male-initiated, and male-centered erotic film excerpt. Photoplethysmographic vaginal pulse amplitude was recorded continuously. Self-report ratings of sexual arousal and affective reactions were collected after

  7. Female distribution affects mate searching and sexual selection in male northern water snakes ( Nerodia sipedon )

    Microsoft Academic Search

    Gregory P. Brown; Patrick J. Weatherhead

    1999-01-01

    Mating systems and sexual selection are assumed to be affected by the distribution of critical resources. We use observations\\u000a of 312 mating aggregations to compare mate-searching success of male northern water snakes (Nerodia sipedon) in two marshes in which differences in mating substrate availability resulted in more than fourfold differences in female\\u000a dispersion. Reproductive males had significantly larger home ranges

  8. Independent effects of male and female density on sexual harassment, female fitness, and male competition for mates in the western mosquitofish Gambusia affinis

    Microsoft Academic Search

    Chad C. Smith

    2007-01-01

    Operational sex ratio (the ratio of sexually active males to fertilizable females) has a major influence on male competition\\u000a for mates and male–female interactions. The contributions of male and female density per se to mating system dynamics, however,\\u000a are rarely examined, and the fitness consequences are often inferred rather than quantified. Male mosquitofish (Gambusia affinis) compete aggressively and frequently harass

  9. Embryonic co-exposure to methoxychlor and Clophen A50 alters sexual behavior in adult male quail

    Microsoft Academic Search

    Krister Halldin; Jeanette Axelsson; Björn Brunström

    2005-01-01

    Embryonic exposure to estrogens and estrogenic pollutants is known to demasculinize sexual behavior in adult male Japanese quail. In the present study, we administered the insecticide methoxychlor to quail eggs at a dose of 150 µg\\/g egg and then studied sexual behavior and other reproductive variables in adult males. In a second experiment we administered the same dose of methoxychlor together

  10. Influences of fraternity membership, athletics, and male living arrangements on sexual aggression.

    PubMed

    Boeringer, S B

    1996-06-01

    This study investigates the association of fraternity membership, athletic participation, and sex composition of living arrangements on sexual coercion. 477 male undergraduates enrolled in Southeastern University were surveyed in classroom settings regarding their experiences with sexual aggression and coercion, as well as their self-reported rape proclivity. From the total sample, 114 (23.9%) reported fraternity membership and about 77 (16.2%) reported intercollegiate athletic participation. The majority of men lived in all-male environments such as all-male floors of dorm towers, apartments, and fraternity houses. The overall age distribution of the sample was concentrated towards younger men, with 18-19 year olds making up 61% of the sample. The results of the study indicated that fraternity members were disproportionately involved in some forms of campus sexual aggression. Although use of physical force or threats were not very prevalent among members, alcohol and drug intoxication played a significant role in obtaining sex. On the other hand, athletes displayed greater rape proclivity, but no greater coercive/aggressive sexual behavior. Also, sex composition of living arrangements has no significant effect on rape proclivity or sexual victimization. PMID:12295455

  11. Effects of circumcision on male sexual functions: a systematic review and meta-analysis

    PubMed Central

    Tian, Ye; Liu, Wei; Wang, Jian-Zhong; Wazir, Romel; Yue, Xuan; Wang, Kun-Jie

    2013-01-01

    This meta-analysis was performed to assess sexual functions following adult male circumcision. We searched the Cochrane Central Register of Controlled Trials, PUBMED, EMBASE, the Cochrane Database of Systematic Review and Web of Science from their inception until January 2013 to identify all eligible studies that reported on men's sexual function after circumcision. The Cochrane Collaboration's RevMan 5.2 software was employed for data analysis, and the fixed or the random effect model was selected depending on the proportion of heterogeneity. We identified 10 studies, which described a total of 9317 circumcised and 9423 uncircumcised men who were evaluated for the association of circumcision with male sexual function. There were no significant differences in sexual desire (odds ratio (OR): 0.99; 95% confidence interval (CI): 0.92–1.06), dyspareunia (OR: 1.12; 95% CI: 0.52–2.44), premature ejaculation (OR: 1.13; 95% CI: 0.83–1.54), ejaculation latency time (OR: 1.33; 95% CI: 0.69–1.97), erectile dysfunctions (OR: 0.90; 95% CI: 0.65–1.25) and orgasm difficulties (OR: 0.97; 95% CI: 0.83–1.13). These findings suggest that circumcision is unlikely to adversely affect male sexual functions. However, these results should be evaluated in light of the low quality of the existing evidence and the significant heterogeneity across the various studies. Well-designed and prospective studies are required for a further understanding of this topic. PMID:23749001

  12. Sexual abuse prevention with high-risk males: the roles of victim empathy and rape myths.

    PubMed

    Schewe, P A; O'Donohue, W

    1993-01-01

    The outcome of two sexual abuse prevention programs, one emphasizing victim empathy and the other stressing modifying rape myths, was evaluated with high-risk males. Sixty-eight high-risk males, as determined by self-reported likelihood of committing sexual abuse, were randomly assigned to an empathy-treatment, a facts-treatment, or a no-treatment control group. Treatment effects were assessed using subjects' pre- and post-treatment scores on the Likelihood of Sexually Abusing scale, the Rape Empathy Scale, the Acceptance of Interpersonal Violence scale, the Adversarial Sexual Beliefs Scale, and a test of self-reported sexual arousal to forced versus consenting sex. In addition, posttest scores on an Asch-type conformity measure were obtained. Results of validity checks indicated that high-risk subjects differed from low-risk subjects on a number of rape-related variables, that the victim-empathy condition increased subjects' empathy, and that subjects found both treatments to be credible and helpful. Comparisons between the empathy-, facts-, and no-treatment group contraindicated the practice of dispelling rape myths as a method of preventing rape among high-risk males. PMID:8060907

  13. Prevalence of Consensual Male–Male Sex and Sexual Violence, and Associations with HIV in South Africa: A Population-Based Cross-Sectional Study

    PubMed Central

    Dunkle, Kristin L.; Jewkes, Rachel K.; Murdock, Daniel W.; Sikweyiya, Yandisa; Morrell, Robert

    2013-01-01

    Background In sub-Saharan Africa the population prevalence of men who have sex with men (MSM) is unknown, as is the population prevalence of male-on-male sexual violence, and whether male-on-male sexual violence may relate to HIV risk. This paper describes lifetime prevalence of consensual male–male sexual behavior and male-on-male sexual violence (victimization and perpetration) in two South African provinces, socio-demographic factors associated with these experiences, and associations with HIV serostatus. Methods and Findings In a cross-sectional study conducted in 2008, men aged 18–49 y from randomly selected households in the Eastern Cape and KwaZulu-Natal provinces provided anonymous survey data and dried blood spots for HIV serostatus assessment. Interviews were completed in 1,737 of 2,298 (75.6%) of enumerated and eligible households. From these households, 1,705 men (97.1%) provided data on lifetime history of same-sex experiences, and 1,220 (70.2%) also provided dried blood spots for HIV testing. 5.4% (n?=?92) of participants reported a lifetime history of any consensual sexual activity with another man; 9.6% (n?=?164) reported any sexual victimization by a man, and 3.0% (n?=?51) reported perpetrating sexual violence against another man. 85.0% (n?=?79) of men with a history of consensual sex with men reported having a current female partner, and 27.7% (n?=?26) reported having a current male partner. Of the latter, 80.6% (n?=?21/26) also reported having a female partner. Men reporting a history of consensual male–male sexual behavior are more likely to have been a victim of male-on-male sexual violence (adjusted odds ratio [aOR]?=?7.24; 95% CI 4.26–12.3), and to have perpetrated sexual violence against another man (aOR?=?3.10; 95% CI 1.22–7.90). Men reporting consensual oral/anal sex with a man were more likely to be HIV+ than men with no such history (aOR?=?3.11; 95% CI 1.24–7.80). Men who had raped a man were more likely to be HIV+ than non-perpetrators (aOR?=?3.58; 95% CI 1.17–10.9). Conclusions In this sample, one in 20 men (5.4%) reported lifetime consensual sexual contact with a man, while about one in ten (9.6%) reported experience of male-on-male sexual violence victimization. Men who reported having had sex with men were more likely to be HIV+, as were men who reported perpetrating sexual violence towards other men. Whilst there was no direct measure of male–female concurrency (having overlapping sexual relationships with men and women), the data suggest that this may have been common. These findings suggest that HIV prevention messages regarding male–male sex in South Africa should be mainstreamed with prevention messages for the general population, and sexual health interventions and HIV prevention interventions for South African men should explicitly address male-on-male sexual violence. Please see later in the article for the Editors' Summary PMID:23853554

  14. Effects of egg testosterone on female mate choice and male sexual behavior in the pheasant.

    PubMed

    Bonisoli-Alquati, Andrea; Matteo, Angelo; Ambrosini, Roberto; Rubolini, Diego; Romano, Maria; Caprioli, Manuela; Dessì-Fulgheri, Francesco; Baratti, Mariella; Saino, Nicola

    2011-01-01

    Evidence is accumulating that sex steroids in the eggs, besides affecting progeny phenotype and behavior in the short term, also have enduring effects until adulthood, when they may translate into differences in reproductive strategies and success. Maternal steroids transfer may therefore affect both agonistic behavior and mate choice decisions, either through the promotion of body size and condition or through a priming effect on the neuroendocrine system. However, owing to the prevalence of a short-term perspective, relevance of maternal transfer of sex steroids to sexual selection processes has been seldom studied. Here we investigate the effects of an experimental increase in egg testosterone on male dominance and copulation success in the ring-necked pheasant, Phasianus colchicus, a polygynous galliform with multiple male ornamental traits, in captivity. We found that females from testosterone (T) injected eggs copulated less than control females. Males from T-injected eggs obtained more copulations than control males, specifically with control females. The effect of male 'ordinary' and secondary sexual traits on either dominance or copulation frequency did not depend on early exposure to T, nor did T treatment affect male dominance. Present results demonstrate that variation in the early hormonal environment set up by mothers affects sexual behavior of the offspring, which might translate into fitness differences. PMID:21029735

  15. Female mate preferences for male body size and shape promote sexual isolation in threespine sticklebacks

    PubMed Central

    Head, Megan L; Kozak, Genevieve M; Boughman, Janette W

    2013-01-01

    Female mate preferences for ecologically relevant traits may enhance natural selection, leading to rapid divergence. They may also forge a link between mate choice within species and sexual isolation between species. Here, we examine female mate preference for two ecologically important traits: body size and body shape. We measured female preferences within and between species of benthic, limnetic, and anadromous threespine sticklebacks (Gasterosteus aculeatus species complex). We found that mate preferences differed between species and between contexts (i.e., within vs. between species). Within species, anadromous females preferred males that were deep bodied for their size, benthic females preferred larger males (as measured by centroid size), and limnetic females preferred males that were more limnetic shaped. In heterospecific mating trials between benthics and limnetics, limnetic females continued to prefer males that were more limnetic like in shape when presented with benthic males. Benthic females showed no preferences for size when presented with limnetic males. These results show that females use ecologically relevant traits to select mates in all three species and that female preference has diverged between species. These results suggest that sexual selection may act in concert with natural selection on stickleback size and shape. Further, our results suggest that female preferences may track adaptation to local environments and contribute to sexual isolation between benthic and limnetic sticklebacks. PMID:23919161

  16. Variation in a female sexual attractiveness pheromone controls male mate choice in garter snakes.

    PubMed

    LeMaster, Michael P; Mason, Robert T

    2002-06-01

    Male red-sided garter snakes (Thamnophis sirtalis parietalis) display a courtship preference for larger females during the breeding season. Utilizing behavioral experiments and chemical analyses, we tested the hypothesis that males can discriminate among females of varying size solely by means of the sexual attractiveness pheromone, a previously characterized sex pheromone composed of a homologous series of long-chain saturated and omega-9 cis-unsaturated methyl ketones contained in the skin lipids of females. When presented with skin lipid extracts from large and small females, a greater proportion of males displayed courtship behaviors to large female extracts. This demonstrates that there is an intrinsic property of the female skin lipids that allows males to differentiate among large and small females. Analysis of the sexual attractiveness pheromone revealed that the necessary variation exists for this pheromone to function as a reliable indicator to males of female body size. Specifically, we observed a strong correlation between female snout-vent length and the relative concentration of saturated and omega-9 cis-unsaturated methyl ketones composing the pheromone; smaller females expressed pheromone profiles higher in saturated methyl ketones. while larger females expressed pheromone profiles dominated by unsaturated methyl ketones. The results of this study suggest that male red-sided garter snakes utilize compositional variation in the female sexual attractiveness pheromone to differentiate among potential mates of varying size. PMID:12184402

  17. Best Clinical Practices for Male Adult Survivors of Childhood Sexual Abuse: “Do No Harm”

    PubMed Central

    Gallo-Silver, Les; Anderson, Christopher M; Romo, Jaime

    2014-01-01

    The health care literature describes treatment challenges and recommended alterations in practice procedures for female survivors of childhood sexual abuse, a subtype of adverse childhood experiences. Currently, there are no concomitant recommendations for best clinical practices for male survivors of childhood sexual abuse or other adverse clinical experiences. Anecdotal information suggests ways physicians can address the needs of adult male survivors of childhood sexual abuse by changes in communication, locus of control, and consent/permission before and during physical examinations and procedures. The intent of this article is to act as a catalyst for improved patient care and more research focused on the identification and optimal responses to the needs of men with adverse childhood experiences in the health care setting. PMID:25106042

  18. Sexual coercion in gay male and lesbian relationships: Predictors and implications for support services

    Microsoft Academic Search

    Caroline K. Waterman; Lori J. Dawson; Michael J. Bologna

    1989-01-01

    Numerous studies have documented the prevalence of forced sex in heterosexual couples. Positive effects of this research include increases in awareness about the problem among helping professionals and the public, as well as increases in support services and prevention programs. However, no research has been done on sexual coercion in gay male and lesbian relationships, and few support services exist.

  19. Self-centeredness and the adult male perpetrator of child sexual abuse

    Microsoft Academic Search

    Jane F. Gilgun

    1988-01-01

    Self-centeredness has been identified as a quality of the adult male perpetrator of child sexual abuse, but little or no effort has been expended toward defining the concept clearly. In this paper, the research literature on the perpetrator and psychoanalytic writings on narcissism are reviewed for the purpose of developing a comprehensive definition of self-centeredness. Literature related to the social

  20. Sexual Health Among Male College Students in the United States and the Netherlands

    ERIC Educational Resources Information Center

    Dodge, Brian; Sandfort, Theo G. M.; Yarber, William L.; de Wit, John

    2005-01-01

    Objectives: To assess differences in sexual health behaviors, outcomes, and potential sociocultural determinants among male college students in the United States and the Netherlands. Methods: Survey data were collected from random samples of students from both national cultures. Results: American men were more likely to report inadequate…

  1. Comparison of Expressed Sequence Tags from Male and Female Sexual Organs of Marchantia polymorpha

    Microsoft Academic Search

    R. Nishiyama; Kenji MIURA; Megumi SAKAIDA; Sachiko OKADA; Kaoru KONO; Masayoshi TAKAHAMA; Takefumi SONE; Mizuki TAKENAKA; Hideya FUKUZAWA; Kanji OHYAMA

    2000-01-01

    A total of 935 expressed sequence tags (ESTs) from male immature sexual organ were determined, of which 600 ESTs were assembled into 110 non-redundant groups, resulting in 445 unique EST sequences. Of these, 244 sequences shared significant similarities to known nucleotide or amino acid sequences in other organisms. The remaining 201 unique sequences showed no significant matches and thus are

  2. Inbreeding affects sexual signalling in males but not females of Tenebrio molitor.

    PubMed

    Pölkki, Mari; Krams, Indrikis; Kangassalo, Katariina; Rantala, Markus J

    2012-06-23

    In many species of animals, individuals advertise their quality with sexual signals to obtain mates. Chemical signals such as volatile pheromones are species specific, and their primary purpose is to influence mate choice by carrying information about the phenotypic and genetic quality of the sender. The deleterious effects of consanguineous mating on individual quality are generally known, whereas the effect of inbreeding on sexual signalling is poorly understood. Here, we tested whether inbreeding reduces the attractiveness of sexual signalling in the mealworm beetle, Tenebrio molitor, by testing the preferences for odours of inbred and outbred (control) individuals of the opposite sex. Females were more attracted to the odours produced by outbred males than the odours produced by inbred males, suggesting that inbreeding reduces the attractiveness of male sexual signalling. However, we did not find any difference between the attractiveness of inbred and outbred female odours, which may indicate that the quality of females is either irrelevant for T. molitor males or quality is not revealed through female odours. PMID:22237501

  3. Extra-pair mating, male plumage coloration and sexual selection in yellow warblers (Dendroica petechia)

    PubMed Central

    Yezerinac, S. M.; Weatherhead, P. J.

    1997-01-01

    Extra-pair mating has been proposed as a source of sexual selection responsible for secondary sexual traits that are common among socially monogamous birds, although supporting evidence is scant. In the socially monogamous yellow warbler, males are larger than females, and unlike females, have extensive reddish streaking on their breasts. Using DNA fingerprinting we show that within-pair parentage was positively related to male size, and that extra-pair mating success was positively related to the amount of streaking on the breast. To our knowledge, this is the first intraspecific evidence of an association between a male plumage ornament and gains of extra-pair paternity that is apparently independent of age. This study confirms that extra-pair mating can be an important mechanism of sexual selection even when the most successful sires are commonly cuckolded, and refutes a previous hypothesis that the variation in plumage and behaviour among male yellow warblers is an example of alternative, equally successful, evolutionarily stable strategies (ESS). More generally, the demonstrated independence of within-pair and extra-pair success and their associated traits indicates that where animals have multiple secondary sexual traits, different traits may be selected by different mechanisms that contribute to total reproductive success.

  4. Sequence variation in the androgen receptor gene is not a common determinant of male sexual orientation

    Microsoft Academic Search

    J. P. Macke; J. Nathans; V. L. King; N. Hu; S. Hu; D. Hamer; M. Bailey; T. Brown

    1993-01-01

    To test the hypothesis that DNA sequence variation in the androgen receptor gene plays a causal role in the development of male sexual orientation, the authors have (1) measured the degree of concordance of androgen receptor alleles in 36 pairs of homosexual brothers, (2) compared the lengths of polyglutamine and polyglycine tracts in the amino-terminal domain of the androgen receptor

  5. Male infanticide and paternity analyses in a socially natural herd of Przewalski's horses: Sexual selection?

    Microsoft Academic Search

    C. Feh; B. Munkhtuya

    2008-01-01

    The sexual selection hypothesis explains infanticide by males in many mammals. In our 11-year study, we investigated this hypothesis in a herd of Przewalski's horses where we had witnessed infanticidal attacks. Infanticide was highly conditional and not simply linked to takeovers. Attacks occurred in only five of 39 cases following a takeover, and DNA paternity revealed that, although infanticidal stallions

  6. Sexuality and HIV\\/AIDS Risk and Perception among Male Street Youths in

    Microsoft Academic Search

    Getnet Tadele

    Objectives: To investigate how male street youths understand and express sexuality and cope with the HIV\\/AIDS risk in their daily lives. Methods: In this ethnographic study, three focus group discussions guided by unstructured questions were held by the author and a peer facilitator with 30 street youths aged 15?24 years. Discussion themes focused on their daily problems and life experiences;

  7. A Neutral Odor May Become a Sexual Incentive through Classical Conditioning in Male Rats

    ERIC Educational Resources Information Center

    Kvitvik, Inger-Line; Berg, Kristine Marit; Agmo, Anders

    2010-01-01

    A neutral olfactory stimulus was employed as CS in a series of experiments with a sexually receptive female as UCS and the execution of an intromission as the UCR. Each experimental session lasted until the male ejaculated. The time the experimental subject spent in a zone adjacent to the source of the olfactory stimulus during the 10 s of CS…

  8. Sexual selection and the Male:Female Mortality Ratio

    Microsoft Academic Search

    Daniel J. Kruger; Randolph M. Nesse

    This paper extends the evolutionary understanding of sex differences in mortality rates by quantifying and graphically examining the overall Male to Female Mortality Ratio (M:F MR) for 11 specific leading causes of death across age groups in the USA, over the course of the lifespan in 20 different countries, and across the past 70 years in 5 countries. The resulting

  9. Environmentally Realistic Exposure to the Herbicide Atrazine Alters Some Sexually Selected Traits in Male Guppies

    PubMed Central

    Shenoy, Kausalya

    2012-01-01

    Male mating signals, including ornaments and courtship displays, and other sexually selected traits, like male-male aggression, are largely controlled by sex hormones. Environmental pollutants, notably endocrine disrupting compounds, can interfere with the proper functioning of hormones, thereby impacting the expression of hormonally regulated traits. Atrazine, one of the most widely used herbicides, can alter sex hormone levels in exposed animals. I tested the effects of environmentally relevant atrazine exposures on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Prolonged atrazine exposure reduced the expression of two honest signals: the area of orange spots (ornaments) and the number of courtship displays performed. Atrazine exposure also reduced aggression towards competing males in the context of mate competition. In the wild, exposure levels vary among individuals because of differential distribution of the pollutants across habitats; hence, differently impacted males often compete for the same mates. Disrupted mating signals can reduce reproductive success as females avoid mating with perceptibly suboptimal males. Less aggressive males are at a competitive disadvantage and lose access to females. This study highlights the effects of atrazine on ecologically relevant mating signals and behaviors in exposed wildlife. Altered reproductive traits have important implications for population dynamics, evolutionary patterns, and conservation of wildlife species. PMID:22312428

  10. The influence of target and perceiver race in the categorisation of male sexual orientation.

    PubMed

    Rule, Nicholas O

    2011-01-01

    Although sexual orientation can be judged from faces, in previous work Caucasian or racially unspecified targets and perceivers have been primarily studied. Here, target and perceiver race were considered in the accurate categorisation of male sexual orientation. Asian, Black, and Caucasian participants categorised the sexual orientations of Asian, Black, and Caucasian men. Accuracy was significantly above chance and consistent across all combinations of perceivers and targets. Response bias scores showed that targets were significantly more likely to be categorised as straight, rather than gay, regardless of target or perceiver race. Moreover, judgments of individual targets were significantly correlated for perceivers from all three groups, suggesting cross-race consistency in target legibility. The perception of sexual orientation from faces therefore appears to be robust against variations in target and perceiver race. PMID:22128555

  11. Male victims of sexual violence in rural Malawi: the overlooked association with HIV infection.

    PubMed

    Conroy, Amy A; Chilungo, Abdallah

    2014-01-01

    In sub-Saharan Africa, research on intimate partner violence (IPV) has largely failed to consider men's experiences as victims by female perpetrators - particularly within ongoing heterosexual relationships such as marriage. The objectives of this study were to document the prevalence of sexual coercion among men, to describe the characteristics of male victims, and to test for an association between sexual coercion and HIV positivity. In 2010, cross-sectional data on HIV risk behaviors, HIV status, and IPV were collected from a sample of 684 mostly married men in rural Malawi. Bivariate analyses were used to examine differences in HIV risk characteristics between victims and nonvictims of sexual coercion. Multivariate logistic regression was used to determine the association between sexual coercion and HIV positivity. Over one-tenth (10.4%) of men reported being a victim of sexual coercion. Male victims of sexual coercion were more likely to be married (p < 0.05), older than 24 years (p < 0.05), physically abused by a female partner (p < 0.001), believed their partners were at higher risk for HIV (p < 0.05), and had consumed alcohol in the past month (p < 0.01). After controlling for potential confounders, the odds of being HIV positive were 7.2 times higher among men who had experienced sexual coercion (p < 0.000). In sub-Saharan Africa, research on men's experience of violence as victims is long overdue. More formative research is needed to understand the mechanisms through which men experience violence and how to appropriately measure IPV among male victims. While the data are cross-sectional and cannot evaluate causality, the strength of the association with HIV positivity merits further attention. PMID:24992179

  12. A 610 KB YAC CLONE HARBORS 7 CM OF TOMATO (LYCOPERSICON ESCULENTUM) DNA THAT INCLUDES THE MALE STERILE 14 GENE AND A HOTSPOT FOR RECOMBINATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pollen development requires both sporophytic and gametophytic gene expression. We are using a map-based cloning technique to isolate sporophytic genes which, when mutant, cause pollen abortion and a male sterile (ms) phenotype in tomato (Lycopersicon esculentum). We have genetically characterized on...

  13. Reversible male sterility in transgenic tobacco carrying a dominant-negative mutated glutamine synthetase gene under the control of microspore-specific promoter.

    PubMed

    Mamun, A N K

    2007-12-01

    Metabolic engineering was used to disrupt glutamine metabolism in microspores in order to block pollen development. We used a dominant-negative mutant (DNM) approach of cytosolic glutamine synthetase (GS1) gene under the microspore-specific promoter NTM19 to block glutamine synthesis in developing pollen grains. We observed partial male sterility in primary transgenic plants by using light microscopy, FDA, DAPI and in vitro pollen germination test. Microspores started to die in the early unicellular microspore stage, pollen viability in all primary transgenic lines ranged from 40-50%. All primary transgenics produced seeds like control plants, hence the inserted gene did not affect the sporophyte and was inherited through the female germline. We regenerated plants by in vitro microspore embryogenesis from 4 individual lines, pollen viability of progeny ranged from 12 to 20%, but some of them also showed 100% male sterility. After foliage spray with glutamine, 100% male-sterile plants were produced viable pollen and seed set was also observed. These results suggested that mutated GS1 activity on microspores had a significant effect on normal pollen development. Back-cross progenies (T2) of DH 100% male-sterile plants showed normal seed set like primary transgenics and control plants. PMID:18254207

  14. Comparison of the organization and expression of mtDNA of fertile and male-sterile sugar beet varieties ( Beta vulgaris L.)

    Microsoft Academic Search

    M. Duchenne; B. Lejeune; P. Fouillard; F. Quetier

    1989-01-01

    Analysis of minicircle occurrence in different samples of sugar beet mitochondrial (mt) DNA invalidates the postulated relationship between cytoplasmic male sterility (CMS) phenotype and the absence of minicircle c and d. In high molecular weight mt DNA, two types of restriction patterns are found for fertile genomes and only one type for the CMS; in spite of the multiplicity of

  15. Cytoplasmic male sterility in Beta is associated with structural rearrangements of the mitochondrial DNA and is not due to interspecific organelle transfer

    Microsoft Academic Search

    Christer Halldén; Christina Lind; Torbjörn Säll; Nils Olof Bosemark; Bengt O. Bengtsson

    1990-01-01

    Summary Chloroplast (ct) and mitochondrial (mt) DNAs from four cytoplasmic male sterile (cms) and 22 normal fertile sugar beet lines and accessions of wild beets from the genusBeta have been compared with restriction analyses and Southern hybridizations. We have used restriction analyses of ctDNA as a phylogenetic marker to confirm the taxonomic relationships between the different cytoplasms. According to the

  16. Additional tests on the efficacy of ginger root oil in enhacing the mating competitiveness of sterile males of the Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies have shown that exposure to the aroma of ginger root oil (Zingiber officinale Roscoe; termed GRO hereafter) increases the mating competitiveness of males of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann). This result suggests that pre-release exposure of sterile ...

  17. Medfly (Diptera:Tephritidae) Genetic Sexing: Large-Scale Field Comparison of Males-Only and Bisexual Sterile Fly Releases in Guatemala

    Microsoft Academic Search

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

    2004-01-01

    The effect of releases of bisexual (males and female) and unisexual (male only) sterilized medßies was compared in three large Þeld evaluations over a 3-yr period (1995Ð1997) in southwestern Guatemala. The two strains tested were a genetic sexing strain, Vienna-4\\/Tol-94, carrying the temperature sensitive tsl gene to eliminate females in the egg stage, and the standard bisexual Petapa strain. Flies

  18. Properties of the linear N1 and N2 plasmid-like DNAs from mitochondria of cytoplasmic male-sterile Sorghum bicolor

    Microsoft Academic Search

    Christine D. Chase; Daryl R. Pring

    1986-01-01

    The linear N1 and N2 plasmid-like DNAs were recovered from mitochondria of the IS1112C line of cytoplasmic male-sterile (CMS) Sorghum bicolor (S. bicolor). Molecular clones containing internal sequences of these plasmids were constructed. These clones were used to probe Southern blots of mitochondrial genomes from six CMS and five male-fertile (MF) lines of S. bicolor, as well as Southern blots

  19. Adverse health outcomes, perpetrator characteristics, and sexual violence victimization among U.S. adult males.

    PubMed

    Choudhary, Ekta; Coben, Jeffrey; Bossarte, Robert M

    2010-08-01

    In the United States, an estimated three million men are victims of sexual violence each year, yet the majority of existing studies have evaluated the consequences and characteristics of victimization among women alone. The result has been a gap in the existing literature examining the physical and psychological consequences of sexual assault among men. The main objective of this study was to identify health outcomes, risk behaviors, and perpetrator/victim relationship characteristics among men who have experienced an attempted or completed sexual assault using data from the sexual violence module of the Behavioral Risk Factor Surveillance System survey. A total of 59,511 male respondents participated in the sexual violence module, and the majority of participants were White (73.7%), between the ages of 35 to 44 years (19.8%), married (69.0%), graduated from college (34.6%), and had an annual household income of more than US$50,000 (49.9%). Stratified multivariate logistic regression models were conducted to test the associations between victimization and health outcomes and risk behaviors controlling for age, marital status, race/ethnicity, income, education, and other potential confounders. Results of these analyses suggest important associations between health and sexual violence victimization. Specifically, men who reported unwanted attempted intercourse and attempted and completed intercourse were more likely to report poor mental health, poor life satisfaction, activity limitations, and lower emotional and social support. The current study extends knowledge of consequences of male sexual violence by considering characteristics of sexual assault and by identifying associations between victimization and a broad range of health indicators. PMID:19940163

  20. Male circumcision and prevention of HIV and sexually transmitted infections

    Microsoft Academic Search

    Ronald H. Gray; Maria J. Wawer; Chelsea B. Polis; Godfrey Kigozi; David Serwadda

    2008-01-01

    Three randomized trials in Africa have shown that adult male circumcision reduces HIV acquisition in men by approximately\\u000a 60%. It is biologically plausible that circumcision reduces HIV risk in men because the inner mucosa of the foreskin is lightly\\u000a keratinized and has a high density of dendritic cells and other HIV target cells, making it vulnerable to HIV infection. Also,

  1. Subcortical multiple unit activity changes during rat male sexual behavior.

    PubMed

    Hernandez-Gonzalez, M; Guevara, M A; Morali, G; Cervantes, M

    1997-02-01

    Multiple unit activity (MUA) was recorded from the ventral tegmental area (VTA) and mesencephalic locomotor region (MLR) during copulatory behavior of freely moving male rats. Simultaneous accelerometric recordings of the copulatory pelvic thrusting performed by the male rat were taken to precisely correlate in time the changes in MUA with well defined elements of copulation. The baseline MUA firing rates recorded in the quiet-alert condition in the VTA and in the MLR were significantly increased during pursuit of the female by the male; significantly higher MUA firing rates were found in the VTA at the 500 ms periods before and during the execution of pelvic thrusting in mount, intromission, and ejaculation responses as compared to the baseline, and returned to this value when these responses ended. The maximum MUA firing rate in the MLR was obtained during the execution of pelvic thrusting in each copulatory response, and it remained significantly elevated, as compared to the baseline, after thrusting and at the postintromission and postejaculatory genital grooming, then decreasing to basal values at the initial part of the postejaculatory interval. The fact that the highest changes in MUA were related to pelvic thrusting suggests a major participation of both structures in the execution of motor copulatory responses. PMID:9035260

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

    PubMed Central

    Bar-Johnson, Michael; Weiss, Petr

    2014-01-01

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

  3. Population genetics of partial male-sterility and the evolution of monoecy and dioecy

    Microsoft Academic Search

    D Charlesworth; B Charlesworth

    1978-01-01

    Selection on reproductive phenotype in plants is studied, using a theoretical model. Fitnesses of mutant phenotypes with altered male and female fertility are derived, assuming an initially hermaphrodite or monoecious population with no self-incompatibility mechanism, with partial self-fertilisation, and with some inbreeding depression. These fitness expressions are used to derive conditions for the spread of such mutations, in terms of

  4. Baculum morphology predicts reproductive success of male house mice under sexual selection

    PubMed Central

    2013-01-01

    Background Diversity in penile morphology is characterised by extraordinary variation in the size and shape of the baculum (penis bone) found in many mammals. Although functionally enigmatic, diversity in baculum form is hypothesised to result from sexual selection. According to this hypothesis, the baculum should influence the outcome of reproductive competition among males within promiscuous mating systems. However, a test of this key prediction is currently lacking. Results Here we show that baculum size explains significant variation in the reproductive success of male house mice under competitive conditions. After controlling for body size and other reproductive traits, the width (but not length) of the house mouse baculum predicts both the mean number of offspring sired per litter and total number of offspring sired. Conclusions By providing the first evidence linking baculum morphology to male reproductive success, our results support the hypothesis that evolutionary diversity in baculum form is driven by sexual selection. PMID:23800051

  5. Differential Mitochondrial Electron Transport through the Cyanide-Sensitive and Cyanide-Insensitive Pathways in Isonuclear Lines of Cytoplasmic Male Sterile, Male Fertile, and Restored Petunia1

    PubMed Central

    Connett, Marie B.; Hanson, Maureen R.

    1990-01-01

    Three pairs of isonuclear lines of cytoplasmic male sterile (CMS) and fertile Petunia cells (Petunia hybrida [Hook] Vilm. and Petunia parodii L.S.M.) grown in suspension culture were examined for sensitivity to inhibitors of respiratory electron transport at time-points after transfer into fresh media. Cells from CMS lines differed from cells of fertile lines in their utilization of the cyanide-insensitive oxidase pathway. Under our culture regime, after approximately 3 days of culture cells from the CMS lines exhibited much lower cyanide-insensitive, salicylhydroxamic acid-sensitive respiration than cells from the fertile lines. This respiratory difference was shown to be specific to the mitochondrial alternative oxidase pathway by using other characteristic inhibitors of mitochondrial electron transport in experiments with isolated mitochondria. Immature anthers from CMS plants also showed lower alternative oxidase activity relative to anthers from male fertile plants, but no such difference was detected in leaf tissue, ovary or perianth tissue, or anthers collected just prior to anthesis. A cell line from a fertile plant carrying a nuclear fertility restorer gene and the CMS cytoplasm exhibited increased activity of the alternative pathway compared with the CMS lines. PMID:16667667

  6. Sexual selection on cuticular hydrocarbons of male sagebrush crickets in the wild

    PubMed Central

    Steiger, Sandra; Ower, Geoffrey D.; Stökl, Johannes; Mitchell, Christopher; Hunt, John; Sakaluk, Scott K.

    2013-01-01

    Cuticular hydrocarbons (CHCs) play an essential role in mate recognition in insects but the form and intensity of sexual selection on CHCs has only been evaluated in a handful of studies, and never in a natural population. We quantified sexual selection operating on CHCs in a wild population of sagebrush crickets, a species in which nuptial feeding by females imposes an unambiguous phenotypic marker on males. Multivariate selection analysis revealed a saddle-shaped fitness surface, suggesting a complex interplay between the total abundance of CHCs and specific CHC combinations in their influence on female choice. The fitness surface resulting from two axes of disruptive selection reflected a trade-off between short- and long-chained CHCs, suggesting that males may be sacrificing some level of desiccation resistance in favour of increased attractiveness. There was a significant correlation between male body size and total CHC abundance, suggesting that male CHCs provide females with a reliable cue for maximizing benefits obtained from males. Notwithstanding the conspicuousness of males’ acoustic signals, our results suggest that selection imposed on males via female mating preferences may be far more complex than previously appreciated and operating in multiple sensory modalities. PMID:24197415

  7. Regulation of cell divisions and differentiation by MALE STERILITY32 is required for anther development in maize

    PubMed Central

    Moon, Jihyun; Skibbe, David; Timofejeva, Ljudmilla; Rachel Wang, Chung-Ju; Kelliher, Timothy; Kremling, Karl; Walbot, Virginia; Zacheus Cande, William

    2014-01-01

    Summary Male fertility in flowering plants relies on proper division and differentiation of cells in the anther, a process that gives rise to four somatic layers surrounding central germinal cells. The maize gene male sterility32 (ms32) encodes a basic helix–loop–helix (bHLH) transcription factor, which functions as an important regulator of both division and differentiation during anther development. After the four somatic cell layers are generated properly through successive periclinal divisions, in the ms32 mutant, tapetal precursor cells fail to differentiate, and, instead, undergo additional periclinal divisions to form extra layers of cells. These cells become vacuolated and expand, and lead to failure in pollen mother cell development. ms32 expression is specific to the pre-meiotic anthers and is distributed initially broadly in the four lobes, but as the anther develops, its expression becomes restricted to the innermost somatic layer, the tapetum. The ms32-ref mac1-1 double mutant is unable to form tapetal precursors and also exhibits excessive somatic proliferation leading to numerous, disorganized cell layers, suggesting a synergistic interaction between ms32 and mac1. Altogether, our results show that MS32 is a major regulator in maize anther development that promotes tapetum differentiation and inhibits periclinal division once a tapetal cell is specified. PMID:24033746

  8. Improving panicle exsertion of rice cytoplasmic male sterile line by combination of artificial microRNA and artificial target mimic.

    PubMed

    Chen, Hao; Jiang, Shan; Zheng, Jie; Lin, Yongjun

    2013-04-01

    The adoption of hybrid rice caused the second leap in rice yield after the 'green revolution' and contributes substantially to food security of China and the world. However, almost all cytoplasmic male sterile lines (A lines) as females of hybrid rice have a natural deficiency of 'panicle enclosure', which blocks pollination between the A line and the fertility restorer line as the male (R line) of hybrid rice and decreases seed yield. In hybrid rice seed production, exogenous '920' (the active ingredient is gibberellin A3 ) must be applied to eliminate or alleviate panicle enclosure of the A line; however, this not only increases production cost and pollutes the environment, it also decreases seed quality. In this study, we designed a transgenic approach to improve plant height and panicle exsertion of the A line to facilitate hybrid rice production and maintain the semi-dwarf plant type of the hybrid. This approach comprising two components-artificial microRNA (amiRNA) and artificial target mimicry-can manipulate the differential expression of the endogenous Eui1 gene that is associated with rice internode elongation in the A line and the hybrid. amiRNA is a recently developed gene silencing method with high specificity, while target mimicry is a natural mechanism inhibiting the miRNA function that was also recently characterized. This approach provides a paradigm to tune the expression of endogenous genes to achieve the desired phenotype by combining amiRNA and artificial target mimicry technologies. PMID:23164055

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

    PubMed

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

    2012-11-01

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

  10. Effects of male sex hormones on gender identity, sexual behavior, and cognitive function.

    PubMed

    Zhu, Yuan-shan; Cai, Li-qun

    2006-04-01

    Androgens, the male sex hormones, play an essential role in male sexual differentiation and development. However, the influence of these sex hormones extends beyond their roles in sexual differentiation and development. In many animal species, sex hormones have been shown to be essential for sexual differentiation of the brain during development and for maintaining sexually dimorphic behavior throughout life. The principals of sex determination in humans have been demonstrated to be similar to other mammals. However, the hormonal influence on sexual dimorphic differences in the nervous system in humans, sex differences in behaviors, and its correlations with those of other mammals is still an emerging field. In this review, the roles of androgens in gender and cognitive function are discussed with the emphasis on subjects with androgen action defects including complete androgen insensitivity due to androgen receptor mutations and 5alpha-reductase-2 deficiency syndromes due to 5alpha-reductase-2 gene mutations. The issue of the complex interaction of nature versus nurture is addressed. PMID:16706106

  11. Social context, sexual risk perceptions and stigma: HIV vulnerability among male sex workers in Mombasa, Kenya.

    PubMed

    Okal, Jerry; Luchters, Stanley; Geibel, Scott; Chersich, Matthew F; Lango, Daniel; Temmerman, Marleen

    2009-11-01

    Knowledge about sexual practices and life experiences of men having sex with men in Kenya, and indeed in East Africa, is limited. Although the impact of male same-sex HIV transmission in Africa is increasingly acknowledged, HIV prevention initiatives remain focused largely on heterosexual and mother-to-child transmission. Using data from ten in-depth interviews and three focus group discussions (36 men), this analysis explores social and behavioural determinants of sexual risks among men who sell sex to men in Mombasa, Kenya. Analysis showed a range and variation of men by age and social class. First male same-sex experiences occurred for diverse reasons, including love and pleasure, as part of sexual exploration, economic exchange and coercion. Condom use is erratic and subject to common constraints, including notions of sexual interference and motivations of clients. Low knowledge compounds sexual risk taking, with a widespread belief that the risk of HIV transmission through anal sex is lower than vaginal sex. Traditional family values, stereotypes of abnormality, gender norms and cultural and religious influences underlie intense stigma and discrimination. This information is guiding development of peer education programmes and sensitisation of health providers, addressing unmet HIV prevention needs. Such changes are required throughout Eastern Africa. PMID:19484638

  12. Reduced melanocortin production causes sexual dysfunction in male mice with POMC neuronal insulin and leptin insensitivity.

    PubMed

    Faulkner, Latrice D; Dowling, Abigail R; Stuart, Ronald C; Nillni, Eduardo A; Hill, Jennifer W

    2015-04-01

    Proopiomelanocortin (POMC)-derived peptides like ?-melanocyte-stimulating hormone (MSH) substantially improve hepatic insulin sensitivity and regulate energy expenditure. Melanocortinergic agents are also powerful inducers of sexual arousal that are being investigated for a possible therapeutic role in erectile dysfunction. It is currently unclear whether reduced melanocortin (MC) activity may contribute to the sexual dysfunction accompanying obesity and type 2 diabetes. Male rodents with leptin and insulin resistance targeted to POMC neurons (leptin receptor [LepR]/insulin receptor [IR]POMC mice) exhibit obesity, hyperinsulinemia, hyperglycemia, and systemic insulin resistance. In this study, we demonstrate that LepR/IRPOMC males are also subfertile due to dramatic alterations in sexual behavior. Remarkably, these reproductive changes are accompanied by decreased ?-MSH production not present when a single receptor type is deleted. Unexpectedly, behavioral sensitivity to ?-MSH and MC receptor expression are also reduced in LepR/IRPOMC males, a potential adaptation of the MC system to altered ?-MSH production. Together, these results suggest that concurrent insulin and leptin resistance in POMC neurons in individuals with obesity or type 2 diabetes can reduce endogenous ?-MSH levels and impair sexual function. PMID:25590244

  13. Impunity or immunity: wartime male rape and sexual torture as a crime against humanity.

    PubMed

    Zawati, Hilmi M

    2007-01-01

    This paper seeks to analyze the phenomenon of wartime rape and sexual torture of Croatian and Iraqi men and to explore the avenues for its prosecution under international humanitarian and human rights law. Male rape, in time of war, is predominantly an assertion of power and aggression rather than an attempt on the part of the perpetrator to satisfy sexual desire. The effect of such a horrible attack is to damage the victim's psyche, rob him of his pride, and intimidate him. In Bosnia- Herzegovina, Croatia, and Iraq, therefore, male rape and sexual torture has been used as a weapon of war with dire consequences for the victim's mental, physical, and sexual health. Testimonies collected at the Medical Centre for Human Rights in Zagreb and reports received from Iraq make it clear that prisoners in these conflicts have been exposed to sexual humiliation, as well as to systematic and systemic sexual torture. This paper calls upon the international community to combat the culture of impunity in both dictator-ruled and democratic countries by bringing the crime of wartime rape into the international arena, and by removing all barriers to justice facing the victims. Moreover, it emphasizes the fact that wartime rape is the ultimate humiliation that can be inflicted on a human being, and it must be regarded as one of the most grievous crimes against humanity. The international community has to consider wartime rape a crime of war and a threat to peace and security. It is in this respect that civilian community associations can fulfill their duties by encouraging victims of male rape to break their silence and address their socio-medical needs, including reparations and rehabilitation. PMID:17456904

  14. Sexual attractiveness in male rats is associated with greater concentration of major urinary proteins.

    PubMed

    Kumar, Vineet; Vasudevan, Anand; Soh, Linda Jing Ting; Le Min, Choo; Vyas, Ajai; Zewail-Foote, Maha; Guarraci, Fay A

    2014-12-01

    Female rats show a distinct attraction for males. This attraction remains consistent without the necessity for the physical presence of the male. However, the identity of the olfactory cues contributing to attraction in rats remains unknown. Rat urine contains copious amounts of major urinary proteins (MUPs). Here, we investigated the hypothesis that MUPs mediate sexual attractiveness in rats. We first demonstrated that a member of a male dyad receiving greater copulatory opportunities in competitive mate choice tests excrete greater amounts of MUPs. Furthermore, the amount of male MUPs positively correlated with both copulatory opportunities received and female exploration of the urine. Using females and a two-choice olfactory attraction test, we demonstrated that urinary fractions containing MUPs were sufficient to induce attraction and that male MUPs activated neurons in the posterodorsal medial amygdala in female rats. Taken together, these results suggest that olfactory cues associated with MUPs act as an attractant to female rats in estrus. PMID:25359898

  15. Behavioral sterility of hybrid males in acoustically communicating grasshoppers (Acrididae, Gomphocerinae)

    Microsoft Academic Search

    Brigitte Gottsberger; Frieder Mayer

    2007-01-01

    The effectiveness of hybridization barriers determines whether two species remain reproductively isolated when their populations\\u000a come into contact. We investigated acoustic mating signals and associated leg movements responsible for song creation of hybrids\\u000a between the grasshopper species Chorthippus biguttulus and C. brunneus to study whether and how songs of male hybrids contribute to reproductive isolation between these sympatrically occurring\\u000a species.

  16. Male sexual dysfunction and infertility associated with neurological disorders

    PubMed Central

    Fode, Mikkel; Krogh-Jespersen, Sheila; Brackett, Nancy L; Ohl, Dana A; Lynne, Charles M; Sønksen, Jens

    2012-01-01

    Normal sexual and reproductive functions depend largely on neurological mechanisms. Neurological defects in men can cause infertility through erectile dysfunction, ejaculatory dysfunction and semen abnormalities. Among the major conditions contributing to these symptoms are pelvic and retroperitoneal surgery, diabetes, congenital spinal abnormalities, multiple sclerosis and spinal cord injury. Erectile dysfunction can be managed by an increasingly invasive range of treatments including medications, injection therapy and the surgical insertion of a penile implant. Retrograde ejaculation is managed by medications to reverse the condition in mild cases and in bladder harvest of semen after ejaculation in more severe cases. Anejaculation might also be managed by medication in mild cases while assisted ejaculatory techniques including penile vibratory stimulation and electroejaculation are used in more severe cases. If these measures fail, surgical sperm retrieval can be attempted. Ejaculation with penile vibratory stimulation can be done by some spinal cord injured men and their partners at home, followed by in-home insemination if circumstances and sperm quality are adequate. The other options always require assisted reproductive techniques including intrauterine insemination or in vitro fertilization with or without intracytoplasmic sperm injection. The method of choice depends largely on the number of motile sperm in the ejaculate. PMID:22138899

  17. Sexually active males prevent the display of seasonal anestrus in female goats.

    PubMed

    Delgadillo, J A; Flores, J A; Hernández, H; Poindron, P; Keller, M; Fitz-Rodríguez, G; Duarte, G; Vielma, J; Fernández, I G; Chemineau, P

    2015-03-01

    A well-defined season of sexual rest controlled by photoperiod is observed in female sheep and goats during spring and summer, delineating their "anestrous season"; bucks also decrease sexual activity at about the same time. Nutrition and/or socio-sexual stimuli play only secondary roles. However, the presence of sexually active males can reduce the length of seasonal anestrus. Whether it can also completely suppress anestrus has not been investigated. Here we tested this in goats in 3 experiments, using bucks rendered sexually active out of season by exposure to long days. The continuous presence of these males prevented goats to display seasonal anestrus: 12/14 females cycled the year round, vs. 0/13 and 0/11 for females with un-treated bucks or without bucks (experiment 1). When active bucks were removed, females immediately entered anestrus (7/7 stopped ovulating vs. 1/7 if maintained with active bucks; experiment 2). Finally, 7/7 anestrous does with bucks in sexual rest since 1.5months commenced cycling rapidly during mid-anestrous, when these bucks became sexually active following a treatment with artificial long days, vs. 0/7 with un-treated bucks or no bucks (experiment 3). The presence/withdrawal of active bucks had a highly significant effect in the three experiments (P?0.002). Therefore, the presence of a mating opportunity can completely override the photoperiodic inhibition of reproduction of females throughout the anestrous season. Results suggest that we must re-evaluate the relative contributions of photoperiod vs. other external cues in controlling seasonal reproduction, thus offering new non-pharmaceutical ways for controlling out-of-season reproduction in small ruminants. PMID:25497417

  18. The Ontogeny of Sexual Size Dimorphism of a Moth: When Do Males and Females Grow Apart?

    PubMed Central

    Stillwell, R. Craig; Daws, Andrew; Davidowitz, Goggy

    2014-01-01

    Sexual dimorphism in body size (sexual size dimorphism) is common in many species. The sources of selection that generate the independent evolution of adult male and female size have been investigated extensively by evolutionary biologists, but how and when females and males grow apart during ontogeny is poorly understood. Here we use the hawkmoth, Manduca sexta, to examine when sexual size dimorphism arises by measuring body mass every day during development. We further investigated whether environmental variables influence the ontogeny of sexual size dimorphism by raising moths on three different diet qualities (poor, medium and high). We found that size dimorphism arose during early larval development on the highest quality food treatment but it arose late in larval development when raised on the medium quality food. This female-biased dimorphism (females larger) increased substantially from the pupal-to-adult stage in both treatments, a pattern that appears to be common in Lepidopterans. Although dimorphism appeared in a few stages when individuals were raised on the poorest quality diet, it did not persist such that male and female adults were the same size. This demonstrates that the environmental conditions that insects are raised in can affect the growth trajectories of males and females differently and thus when dimorphism arises or disappears during development. We conclude that the development of sexual size dimorphism in M. sexta occurs during larval development and continues to accumulate during the pupal/adult stages, and that environmental variables such as diet quality can influence patterns of dimorphism in adults. PMID:25184664

  19. Extra-marital sexual partnerships and male friendships in rural Malawi

    PubMed Central

    Clark, Shelley

    2010-01-01

    Extra-marital sexual partnerships (EMSPs) are a major route of HIV/AIDS transmission in sub-Saharan Africa. In this paper, we investigate the roles of two types of male friendships – best friends and friends with whom they talk about AIDS – in determining whether men have EMSPs. Using data from men in rural Malawi, we find that men's current extra-marital sexual behavior is most closely correlated with their best friends', but that the behaviors of both types of friends are associated with men's subsequent EMSPs. These findings suggest that men's friendships could be used to help combat the AIDS epidemic. PMID:20531977

  20. An alloplasmic male-sterile line of Brassica oleracea harboring the mitochondria from Diplotaxis muralis expresses a novel chimeric open reading frame, orf72.

    PubMed

    Shinada, Tomotaka; Kikuchi, Yosuke; Fujimoto, Ryo; Kishitani, Sachie

    2006-04-01

    Nuclear so-called fertility-restorer genes reverse the pollen sterility of cytoplasmic male-sterile (CMS) plants caused by disturbed mitochondrial-nuclear interactions. We identified a CMS-associated chimeric mitochondrial gene in an alloplasmic CMS line of Brassica oleracea in the 'mur' system. This novel chimeric gene, orf72, was found in the mitochondrial genome of donor cytoplasm. It was located downstream of normal rps7 and contained part of atp9 (atp9-b). It was expressed specifically on the nuclear background of CMS B. oleracea, partially suppressed in the fertility-restored line and entirely suppressed in the cytoplasmic donor. PMID:16434434

  1. Prevalence rates of male and female sexual violence perpetrators in a national sample of adolescents.

    PubMed

    Ybarra, Michele L; Mitchell, Kimberly J

    2013-12-01

    IMPORTANCE Sexual violence can emerge in adolescence, yet little is known about youth perpetrators-especially those not involved with the criminal justice system. OBJECTIVE To report national estimates of adolescent sexual violence perpetration and details of the perpetrator experience. DESIGN, SETTING, AND PARTICIPANTS Data were collected online in 2010 (wave 4) and 2011 (wave 5) in the national Growing Up With Media study. Participants included 1058 youths aged 14 to 21 years who at baseline read English, lived in the household at least 50% of the time, and had used the Internet in the last 6 months. Recruitment was balanced on youths' biological sex and age. MAIN OUTCOMES AND MEASURES Forced sexual contact, coercive sex, attempted rape, and completed rape. RESULTS Nearly 1 in 10 youths (9%) reported some type of sexual violence perpetration in their lifetime; 4% (10 females and 39 males) reported attempted or completed rape. Sixteen years old was the mode age of first sexual perpetration (n?=?18 [40%]). Perpetrators reported greater exposure to violent X-rated content. Almost all perpetrators (98%) who reported age at first perpetration to be 15 years or younger were male, with similar but attenuated results among those who began at ages 16 or 17 years (90%). It is not until ages 18 or 19 years that males (52%) and females (48%) are relatively equally represented as perpetrators. Perhaps related to age at first perpetration, females were more likely to perpetrate against older victims, and males were more likely to perpetrate against younger victims. Youths who started perpetrating earlier were more likely than older youths to get in trouble with caregivers; youths starting older were more likely to indicate that no one found out about the perpetration. CONCLUSIONS AND RELEVANCE Sexual violence perpetration appears to emerge earlier for males than females, perhaps suggesting different developmental trajectories. Links between perpetration and violent sexual media are apparent, suggesting a need to monitor adolescents' consumption of this material. Victim blaming appears to be common, whereas experiencing consequences does not. There is therefore urgent need for school programs that encourage bystander intervention as well as implementation of policies that could enhance the likelihood that perpetrators are identified. PMID:24100409

  2. The sexually dimorphic medial preoptic nucleus of quail: a key brain area mediating steroid action on male sexual behavior.

    PubMed

    Panzica, G C; Viglietti-Panzica, C; Balthazart, J

    1996-01-01

    About 10 years ago, a sexually differentiated nucleus was identified in the preoptic area (POA) of the Japanese quail in the course of studies analyzing the dimorphic mechanisms involved in the activation of sexual behavior. In this species, males exposed to testosterone copulate while females never show this masculine behavior. The present paper reviews anatomical, neurochemical, and functional data that have been collected since that time about the quail dimorphic nucleus. The medial preoptic nucleus (POM) is significantly larger in adult male than in adult female quail. Its volume is also steroid-sensitive in adulthood: it decreases when circulating levels of testosterone are low (castration, exposure to short-days) and it increases when testosterone levels are high (treatment with testosterone, exposure to long-days). The POM is a necessary and sufficient site of steroid action for the activation of male copulatory behavior. The volumetric difference of the POM results from a difference in the adult hormonal milieu of males and females (activational effect) and is not affected by embryonic treatments that permanently modify sexual behavior (no organizational effects on POM). In contrast, the size of neurons in the dorsolateral part of POM appears to be irreversibly affected by embryonic steroids and this feature is therefore a better correlate of the behavioral sex difference. The POM is characterized by the presence of a wide variety of neurotransmitters, neuropeptides, and receptors. It can, in addition, be specifically distinguished from the surrounding POA by the presence of aromatase-immunoreactive cells, by a high density of alpha 2-adrenergic receptors, and by a dense vasotocinergic innervation. Some of these neurochemical markers of the dimorphic nucleus are themselves modulated by steroids. In particular, the aromatase-immunoreactive cells of the lateral POM appear to be a key target for steroids in the activation of male copulatory behavior. The POM is bidirectionally connected to many brain areas. It receives inputs from a variety of sensory areas and from a number of regulatory areas (e.g., catecholaminergic cell groups). This nucleus also sends outputs to "neurovegetative" centers and to brain regions directly connected to the motor pathways. These connections fully support the role of the POM as an integrative center for the control of male sexual behavior. The available data indicate that there is a high degree of steroid-induced neuronal plasticity in the POM, including changes in neuronal function, in protein synthesis, and in specific inputs. These phenomena can easily be studied in the POM because they are of a large magnitude, they are localized in a specific brain site, and they develop rapidly after exposure to steroids. They are also directly related to a clear functional output, the activation of male sexual behavior. The quail POM therefore constitutes an exceptional model for the analysis of steroid-induced brain plasticity in a functionally relevant context. PMID:8788569

  3. Genetic differences among populations in sexual dimorphism: evidence for selection on males in a dioecious plant.

    PubMed

    Yu, Q; Ellen, E D; Wade, M J; Delph, L F

    2011-05-01

    Genetic variation among populations in the degree of sexual dimorphism may be a consequence of selection on one or both sexes. We analysed genetic parameters from crosses involving three populations of the dioecious plant Silene latifolia, which exhibits sexual dimorphism in flower size, to determine whether population differentiation was a result of selection on one or both sexes. We took the novel approach of comparing the ratio of population differentiation of a quantitative trait (Q(ST) ) to that of neutral genetic markers (F(ST) ) for males vs. females. We attributed 72.6% of calyx width variation in males to differences among populations vs. only 6.9% in females. The Q(ST) /F(ST) ratio was 4.2 for males vs. 0.4 for females, suggesting that selection on males is responsible for differentiation among populations in calyx width and its degree of sexual dimorphism. This selection may be indirect via genetic correlations with other morphological and physiological traits. PMID:21401772

  4. Molecular cloning and expression of the male sterility-related CtYABBY1 gene in flowering Chinese cabbage (Brassica campestris L. ssp chinensis var. parachinensis).

    PubMed

    Zhang, X L; Zhang, L G

    2014-01-01

    Expression of the YABBY gene family in the abaxial surface of lateral plant organs determines abaxial destiny of cells, enhances growth and expansion of lateral organs, and plays an important role in polar establishment of lateral organs. However, the YABBY gene has not been studied in male sterility and fertility restoration. We homologously cloned the CtYABBY1 gene of male-sterile TC1 in Brassica campestris L. ssp chinensis var. parachinensis; its expression was analyzed by real-time PCR. A 937-bp sequence was cloned from TC1 and named CtYABBY1. The ORF of this gene has 702 bp, contains a "C2C2 zinc finger" motif at the N-terminal end, and a "YABBY" structural domain at the C-terminal end. This gene had the highest homology with DBC43-3-2 gene in B. campetris ssp pekinensis. Expression of CtYABBY1 gene has a wide range of functions. It is involved in growth and development of lateral organs, such as leaves and flowers, enhancing expansion of the area and volume of young organs. CtYABBY1 is a gene that promotes thermo-sensitive fertility restoration. At room temperature, expression level of this gene was found to be lower in the stamens of sterile flowers. After treating TC1 at a low temperature of 2°-6°C for 20 days, expression of this gene was upregulated in the stamen of fertile flowers. We conclude that male sterility in TC1 is negatively regulated by this gene, which facilitates transition from male sterility to fertility. PMID:25036178

  5. Pharmacophagy of methyl eugenol by males enhances sexual selection of Bactrocera carambolae.

    PubMed

    Wee, Suk-Ling; Tan, Keng-Hong; Nishida, Ritsuo

    2007-06-01

    After pharmacophagy of methyl eugenol (ME), males of Bactrocera carambolae (Diptera: Tephritidae) produced (E)-coniferyl alcohol (CF) along with its endogenously synthesized pheromonal compounds. CF was shown to be released into the air by the ME-fed males only during the courtship period at dusk and attracted significantly more males and females than the ME-deprived males in wind tunnel assays. However, earlier onset of sexual attraction and a higher mating success were observed only in the wind tunnel and field cage assays on the third day posttreatment of ME. Field cage observations on the male-to-male interaction indicated that the ME-deprived males did not exhibit aggregation behavior, but that ME feeding promoted aggregation behavior in B. carambolae. Field cage observations revealed that the ME-deprived males were not only attracted to the ME-fed males, but also appeared to feed on their anal secretions. The secretions were subsequently confirmed to contain CF along with endogenously produced pheromonal compounds. Results obtained for B. carambolae were compared to those previously obtained from its sibling species, Bactrocera dorsalis, and are discussed in light of species advancement in fruit fly-plant relationships. PMID:17443401

  6. Differential screening of mitochondrial cDNA libraries from male-fertile and cytoplasmic male-sterile sugar-beet reveals genome rearrangements at atp6 and atpA loci

    Microsoft Academic Search

    Yongbiao Xue; Sylvie Collin; D. Roy Davies; Colwyn M. Thomas

    1994-01-01

    As part of a strategy to define differences in genome organization and expression between cytoplasmic male-sterile (CMS) and male-fertile (MF) sugar-beet mitochondria, cDNA libraries from both mitochondrial genotypes were constructed. Preliminary screening with ribosomal RNA gene probes identified candidate cDNA clones corresponding to structural genes. In addition, reciprocal hybridization experiments were performed using labelled first-strand cDNA to identify uniquely transcribed

  7. Indiscriminate Males: Mating Behaviour of a Marine Snail Compromised by a Sexual Conflict?

    PubMed Central

    Johannesson, Kerstin; Saltin, Sara H.; Duranovic, Iris; Havenhand, Jon N.; Jonsson, Per R.

    2010-01-01

    Background In promiscuous species, male fitness is expected to increase with repeated matings in an open-ended fashion (thereby increasing number of partners or probability of paternity) whereas female fitness should level out at some optimal number of copulations when direct and indirect benefits still outweigh the costs of courtship and copulation. After this fitness peak, additional copulations would incur female fitness costs and be under opposing selection. Hence, a sexual conflict over mating frequency may evolve in species where females are forced to engage in costly matings. Under such circumstance, if females could avoid male detection, significant fitness benefits from such avoidance strategies would be predicted. Methodology/Principal Findings Among four Littorina species, one lives at very much higher densities and has a longer mating season than the other three species. Using video records of snail behaviour in a laboratory arena we show that males of the low-density species discriminate among male and female mucous trails, trailing females for copulations. In the high-density species, however, males fail to discriminate between male and female trails, not because males are unable to identify female trails (which we show using heterospecific females), but because females do not, as the other species, add a gender-specific cue to their trail. Conclusions/Significance We conclude that there is likely a sexual conflict over mating frequency in the high-density species (L. saxatilis) owing to females most likely being less sperm-limited in this species. This has favoured the evolution of females that permanently or optionally do not release a cue in the mucus to decrease excessive and costly matings resulting in unusually high frequencies of male-male copulating attempts in the wild. This is one of few examples of masking gender identity to obtain fewer matings. PMID:20711254

  8. Variation in neural V1aR predicts sexual fidelity and space use among male prairie voles

    E-print Network

    Indiana University

    Variation in neural V1aR predicts sexual fidelity and space use among male prairie voles in semi, 2007) Although prairie voles (Microtus ochrogaster) are socially monog- amous, males vary in both receptor (V1aR). We investigated individual differences in forebrain V1aR expression of male prairie voles

  9. What Is so Special about Male Adolescent Sexual Offending? A Review and Test of Explanations through Meta-Analysis

    ERIC Educational Resources Information Center

    Seto, Michael C.; Lalumiere, Martin L.

    2010-01-01

    We tested special and general explanations of male adolescent sexual offending by conducting a meta-analysis of 59 independent studies comparing male adolescent sex offenders (n = 3,855) with male adolescent non-sex offenders (n = 13,393) on theoretically derived variables reflecting general delinquency risk factors (antisocial tendencies),…

  10. Male clasping ability, female polymorphism and sexual conflict: fine-scale elytral morphology as a sexually antagonistic adaptation in female diving beetles.

    PubMed

    Karlsson Green, Kristina; Kovalev, Alexander; Svensson, Erik I; Gorb, Stanislav N

    2013-09-01

    During sexual conflict, males and females are expected to evolve traits and behaviours with a sexually antagonistic function. Recently, sexually antagonistic coevolution was proposed to occur between male and female diving beetles (Dytiscidae). Male diving beetles possess numerous suction cups on their forelegs whereas females commonly have rough structures on their elytra. These rough structures have been suggested to obstruct adhesion from male suction cups during mating attempts. However, some diving beetle species are dimorphic, where one female morph has a rough elytra and the other has a smooth elytra. Here, we used biomechanics to study the adhesive performance of male suction cups on the female morphs in two diving beetle species: Dytiscus lapponicus and Graphoderus zonatus. We compared adhesion on the rough and the smooth female morphs to infer the function of the rough elytral modifications. We found that the adhesive force on the rough structures was much lower than on other surfaces. These findings support the suggestion of sexual conflict in diving beetles and a sexually antagonistic function of the rough female structures. In addition, males differed in their adhesive capacity on different female surfaces, indicating a male trade-off between adhering to smooth and rough female morphs. PMID:23825114

  11. Positive genetic correlation between brain size and sexual traits in male guppies artificially selected for brain size.

    PubMed

    Kotrschal, A; Corral-Lopez, A; Zajitschek, S; Immler, S; Maklakov, A A; Kolm, N

    2015-04-01

    Brain size is an energetically costly trait to develop and maintain. Investments into other costly aspects of an organism's biology may therefore place important constraints on brain size evolution. Sexual traits are often costly and could therefore be traded off against neural investment. However, brain size may itself be under sexual selection through mate choice on cognitive ability. Here, we use guppy (Poecilia reticulata) lines selected for large and small brain size relative to body size to investigate the relationship between brain size, a large suite of male primary and secondary sexual traits, and body condition index. We found no evidence for trade-offs between brain size and sexual traits. Instead, larger-brained males had higher expression of several primary and precopulatory sexual traits - they had longer genitalia, were more colourful and developed longer tails than smaller-brained males. Larger-brained males were also in better body condition when housed in single-sex groups. There was no difference in post-copulatory sexual traits between males from the large- and small-brained lines. Our data do not support the hypothesis that investment into sexual traits is an important limiting factor to brain size evolution, but instead suggest that brain size and several sexual traits are positively genetically correlated. PMID:25705852

  12. A case of severe anal injury in an adolescent male due to bestial sexual experimentation.

    PubMed

    Blevins, Roger O

    2009-10-01

    This report delineates a case of anal injury in a 12-year-old boy who gave a detailed history of bestial behavior with a male bulldog. The child described how he had seen this behavior modeled on the internet and subsequently initiated contact with his own dog, causing the dog to penetrate him anally. This type of juvenile bestial behavior with injury has only been reported once previously in the medical literature. Zoophilia, along with a number of other paraphilias, frequently has its onset in the adolescent age group. Adolescents evidencing paraphilic behaviors require thorough psychological evaluation. Spontaneous sexual assault of a human by a canine has never been described in the human or veterinary medical literature, nor is such a thing likely. A clinician involved in evaluating serious ano-genital injury in a child reportedly due to spontaneous canine sexual assault must consider other possible traumatic etiologies including sexual abuse. Investigation in any such case is essential. PMID:19733331

  13. Anxious Attachment, Social Isolation, and Indicators of Sex Drive and Compulsivity: Predictors of Child Sexual Abuse Perpetration in Adolescent Males?

    PubMed

    Miner, Michael H; Swinburne Romine, Rebecca; Robinson, Beatrice Bean E; Berg, Dianne; Knight, Raymond A

    2014-08-20

    It has been suggested that child sexual abuse is related to poor attachment to parents, which is associated with an inability to form intimate relationships. Seto and Lalumière indicated that there were too few studies of adolescent males to determine whether poor attachment was associated with perpetration. This study was designed to follow up on a previous study and further explored the association between insecure attachment to parents, social isolation, and interpersonal adequacy to child sexual abuse perpetration in adolescents. We compared two samples of adolescent males who had committed sexual offenses, those who committed offenses against children (n = 140) and those who committed offenses against peer or adults (n = 92), with a sample of similarly aged males in treatment for mental health or substance use issues (n = 93). Data were collected using a semi-structured interview and computer-administered questionnaire. We found an indirect association between anxious attachment and sexual offenses against child victims, which was accounted for by measures of social involvement and social isolation. These involvement and isolation measures also did not have a direct association with sexual offenses against child victims, in that their contribution was accounted for by a measure of Masculine Adequacy. This Masculine Adequacy, combined with decreased levels of Sexual Preoccupation and Hypersexuality and increased Sexual Compulsivity, was associated with commission of child sexual abuse. The interpersonal variables did not enter a model predicting sexual offending against peers/adults, which seemed solely associated with the interaction between Sexual Compulsivity and Hypersexuality. PMID:25143437

  14. Male sexual polymorphism, alternative reproductive tactics, and androgens in combtooth blennies (pisces: blenniidae).

    PubMed

    Oliveira, R F; Canario, A V; Grober, M S

    2001-09-01

    In species in which intense intermale competition for the access to females is present males of lower competitive ability may adopt alternative reproductive tactics (ART) to get access to mates. These ART translate in many cases into male sexual polymorphism, with individuals following distinctly different tactics. Usually two alternative male morphs can be recognized in species with ART: (1) bourgeois males that compete for access to mates invest in typically male behaviors, such as building elaborated nests or displaying ornaments; and (2) parasitic males that take advantage of the success of the bourgeois males in attracting females and attempt "sneaker" fertilizations (e.g., sneaker and satellite males). In combtooth blennies (Blenniidae) the co-occurrence of ART and male sexual polymorphism has been described for two temperate species: the peacock blenny, Salaria pavo, and the Azorean rock-pool blenny, Parablennius sanguinolentus parvicornis. Interestingly, while in the peacock blenny the alternative male morph adopts a sneaker tactic, in the rock-pool blenny parasitic males act as satellites to nest-holder males. Thus, this variation in the ART expressed in these two closely related species allows for a comparative study of the proximate and ultimate factors affecting the expression of the two ART. In this article we summarize the available information on androgen levels in bourgeois and parasitic males of natural populations of the two species and of recent studies on the effect of exogenous administration of androgens on tactic switching in parasitic males of the two species. The information is discussed within the frame of the relative plasticity hypothesis, which predicts that plastic alternative morphs should show differences in hormone levels and that the administration of sex steroids should be effective in promoting the switch from the parasitic to bourgeois tactic. The evidence is only partly consistent with this hypothesis. Alternatively, a social transduction hypothesis that better fits the available data on androgens and ART in teleost is proposed. It states that the observed differences in androgen levels between alternative morphs should not be interpreted as an organization vs activation effect of steroids, but rather as the limited vs lifelong responsiveness of the neuroendocrine axis to social regulation. PMID:11534991

  15. Evolution of male life histories and age-dependent sexual signals under female choice

    PubMed Central

    2013-01-01

    Sexual selection theory models evolution of sexual signals and preferences using simple life histories. However, life-history models predict that males benefit from increasing sexual investment approaching old age, producing age-dependent sexual traits. Age-dependent traits require time and energy to grow, and will not fully mature before individuals enter mating competition. Early evolutionary stages pose several problems for these traits. Age-dependent traits suffer from strong viability selection and gain little benefit from mate choice when rare. Few males will grow large traits, and they will rarely encounter choosy females. The evolutionary origins of age-dependent traits therefore remain unclear. I used numerical simulations to analyze evolution of preferences, condition (viability) and traits in an age-structured population. Traits in the model depended on age and condition (“good genes”) in a population with no genetic drift. I asked (1) if age-dependent indicator traits and their preferences can originate depending on the strength of selection and the size of the trait; (2) which mode of development (age-dependent versus age-independent) eventually predominates when both modes occur in the population; and (3) if age-independent traits can invade a population with age-dependent traits. Age-dependent traits evolve under weaker selection and at smaller sizes than age-independent traits. This result held in isolation and when the types co-occur. Evolution of age-independent traits depends only on trait size, whereas evolution of age-dependent traits depends on both strength of selection and growth rate. Invasion of age-independence into populations with established traits followed a similar pattern with age-dependence predominating at small trait sizes. I suggest that reduced adult mortality facilitates sexual selection by favoring the evolution of age-dependent sexual signals under weak selection. PMID:24392289

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

    PubMed

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

    2014-05-01

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

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

    PubMed Central

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

    2013-01-01

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

  18. Somatosensory conditioning of sexual arousal and copulatory behavior in the male rat: a model of fetish development.

    PubMed

    Pfaus, James G; Erickson, Kirsten A; Talianakis, Stella

    2013-10-01

    Previous studies have established that neutral olfactory cues associated with sexual reward or inhibition become conditioned stimuli that direct male or female rats toward or away from potential sex partners bearing the cue. Here we examined the ability of a somatosensory cue to exert stimulus control over sexual arousal and copulation in male rats. In the first experiment, two groups of sexually naïve male rats had their first copulatory experiences with receptive females in bilevel chambers with or without a rodent jacket. On a final copulatory test, half of the rats in each group were tested with the jacket on or off. Rats trained and tested without the jacket copulated normally, as did rats trained and tested with the jacket on, and rats trained without the jacket but tested with the jacket on. However, significantly fewer rats trained with the jacket on but tested with the jacket off copulated to ejaculation, and those that did made significantly fewer anticipatory level changes and had fewer significantly longer mount, intromission, and ejaculatory latencies, and fewer ejaculations. In the second experiment, one group of sexually naïve males was given differential conditioning trials in bilevel chambers to associate the jacket on with sexual reward (copulation to ejaculation with a sexually receptive female) and the jacket off with sexual inhibition (thwarted copulatory attempts with a sexually nonreceptive female). A second group had the opposite order of association. A final test with receptive females was made for all males with the jacket on. Males trained to associate the jacket with excitation displayed normal copulation whereas males trained to associate the jacket with inhibition displayed significantly fewer anticipatory level changes and ejaculations, and had significantly longer ejaculation latencies. Thus, somatosensory cues can signal sexual excitation or inhibition in male rats depending on the conditioning history. PMID:23954746

  19. "I connect with the ringleader:" health professionals' perspectives on promoting the sexual health of adolescent males.

    PubMed

    Garcia, Carolyn M; Ptak, Stephanie J; Stelzer, E Brooke; Harwood, Eileen M; Brady, Sonya S

    2014-12-01

    In-depth interviews with nine professionals in adolescent health were used to identify perceived barriers, facilitators, and innovative strategies to reach, engage, and serve adolescent males for sexual and reproductive health care. Barriers included stigma, embarrassment, and lack of social norms around sexually transmitted infection (STI) testing for men. Facilitators included crisis situations and partner support. Clinic-based approaches to reach and engage young men included developing authentic staff-youth engagement and ensuring that access to services is easy and appealing. To be innovative, providers should become part of the real-world context of adolescent males. Technology (e.g., text messaging) and social media can be utilized to target and eliminate barriers to health care among young men. PMID:25354398

  20. Medical and social aspects of sexual assault of males: a survey of 100 victims.

    PubMed Central

    Hillman, R J; O'Mara, N; Taylor-Robinson, D; Harris, J R

    1990-01-01

    Sexual assault of males is an infrequently reported and a poorly understood phenomenon. Details of 100 victims who sought assistance from a nationwide agency set up specifically to provide help for such individuals are reported here. Twenty eight victims were aged 16 years or over at the time of assault. The assailants were known by 72 of the victims and were perceived by the victim to have a heterosexual orientation in 72% of these cases. Attacks were often multiple and in 33 cases involved disruption of skin or mucous membranes. Twenty victims received threats about the possibility of transmission of the human immunodeficiency virus and 17 victims sought medical advice following the assault, most commonly from their general practitioner. It is suggested that greater opportunities for medical and psychological support should be given to male victims of sexual assault. PMID:2282228