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Sample records for sterile male sexual

  1. Sterility and Sexual Competitiveness of Tapachula-7 Anastrepha ludens Males Irradiated at Different Doses.

    PubMed

    Orozco-Dávila, Dina; Adriano-Anaya, Maria de Lourdes; Quintero-Fong, Luis; Salvador-Figueroa, Miguel

    2015-01-01

    A genetic sexing strain of Anastrepha ludens (Loew), Tapachula-7, was developed by the Mexican Program Against Fruit Flies to produce and release only males in programs where the sterile insect technique (SIT) is applied. Currently, breeding are found at a massive scale, and it is necessary to determine the optimum irradiation dose that releases sterile males with minimum damage to their sexual competitiveness. Under laboratory and field conditions, we evaluated the effects of gamma irradiation at doses of 0, 20, 40, 60 and 80 Gy on the sexual competitiveness of males, the induction of sterility in wild females and offspring survivorship. The results of the study indicate that irradiation doses have a significant effect on the sexual behavior of males. A reduction of mating capacity was inversely proportional to the irradiation dose of males. It is estimated that a dose of 60 Gy can induce more than 99% sterility in wild females. In all treatments, the degree of offspring fertility was correlated with the irradiation dose of the parents. In conclusion, the results of the study indicate that a dose of 60 Gy can be applied in sterile insect technique release programs. The application of this dose in the new genetic sexing strain of A. ludens is discussed.

  2. Sterility and Sexual Competitiveness of Tapachula-7 Anastrepha ludens Males Irradiated at Different Doses

    PubMed Central

    Orozco-Dávila, Dina; Adriano-Anaya, Maria de Lourdes; Quintero-Fong, Luis; Salvador-Figueroa, Miguel

    2015-01-01

    A genetic sexing strain of Anastrepha ludens (Loew), Tapachula-7, was developed by the Mexican Program Against Fruit Flies to produce and release only males in programs where the sterile insect technique (SIT) is applied. Currently, breeding are found at a massive scale, and it is necessary to determine the optimum irradiation dose that releases sterile males with minimum damage to their sexual competitiveness. Under laboratory and field conditions, we evaluated the effects of gamma irradiation at doses of 0, 20, 40, 60 and 80 Gy on the sexual competitiveness of males, the induction of sterility in wild females and offspring survivorship. The results of the study indicate that irradiation doses have a significant effect on the sexual behavior of males. A reduction of mating capacity was inversely proportional to the irradiation dose of males. It is estimated that a dose of 60 Gy can induce more than 99% sterility in wild females. In all treatments, the degree of offspring fertility was correlated with the irradiation dose of the parents. In conclusion, the results of the study indicate that a dose of 60 Gy can be applied in sterile insect technique release programs. The application of this dose in the new genetic sexing strain of A. ludens is discussed. PMID:26274926

  3. Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements.

    PubMed

    Liendo, M C; Devescovi, F; Bachmann, G E; Utgés, M E; Abraham, S; Vera, M T; Lanzavecchia, S B; Bouvet, J P; Gómez-Cendra, P; Hendrichs, J; Teal, P E A; Cladera, J L; Segura, D F

    2013-02-01

    Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competitiveness of sterile laboratory males and females that were treated with methoprene (either the pupal or adult stage) and were kept under different regimes of adult food, which varied in the protein source and the sugar:protein ratio. Experiments were carried out under semi-natural conditions, where laboratory flies competed over copulations with sexually mature wild flies. Sterile, methoprene-treated males that reached sexual maturity earlier (six days old), displayed the same lekking behaviour, attractiveness to females and mating competitiveness as mature wild males. This effect depended on protein intake. Diets containing sugar and hydrolyzed yeast allowed sterile males to compete with wild males (even at a low concentration of protein), while brewer´s yeast failed to do so even at a higher concentration. Sugar only fed males were unable to achieve significant numbers of copulations. Methoprene did not increase the readiness to mate of six-day-old sterile females. Long pre-copulatory periods create an additional cost to the management of fruit fly pests through the sterile insect technique (SIT). Our findings suggest that methoprene treatment will increase SIT effectiveness against A. fraterculus when coupled with a diet fortified with protein. Additionally, methoprene acts as a physiological sexing method, allowing the release of mature males and immature females and hence increasing SIT efficiency.

  4. Male sterility and hybrid seed production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual reproduction in angiosperms is a complex process that includes a portion of the vegetative generation and all of the sexual generation. Coordination of both female and male reproduction ontogenies must occur. An abnormality anywhere in this process may lead to sterility. Genetic (nuclear) and...

  5. Manipulation of the microbiota of mass-reared Mediterranean fruit flies Ceratitis capitata (Diptera: Tephritidae) improves sterile male sexual performance.

    PubMed

    Ben Ami, Eyal; Yuval, Boaz; Jurkevitch, Edouard

    2010-01-01

    The sterile insect technique (SIT) is a method of biological control whereby millions of factory reared sterile male insects are released into the field. This technique is commonly used to combat the Mediterranean fruit fly (Ceratitis capitata, Diptera: Tephritidae). Sterile medfly males are less competent in attracting and mating with wild females, a property commonly linked to the irradiation process responsible for the sterilization. As bacteria are important partners in the fly's life cycle, we used molecular analytical methods to study the community structure of the gut microbiota in irradiated male medflies. We find that the sterilizing irradiation procedure affects the gut bacterial community structure of the Mediterranean fruit fly. Although the Enterobacteriaceae family remains the dominant bacterial group present in the gut, the levels of Klebsiella species decreases significantly in the days after sterilization. In addition, we detected substantial differences in some bacterial species between the mass rearing strain Vienna 8 and the wild strain. Most notable among these are the increased levels of the potentially pathogenic species Pseudomonas in the industrial strain. Testing the hypothesis that regenerating the original microbiota community could result in enhanced competitiveness of the sterile flies, we found that the addition of the bacterial species Klebsiella oxytoca to the postirradiation diet enables colonization of these bacteria in the gut while resulting in decreased levels of the Pseudomonas sp. Feeding on diets containing bacteria significantly improved sterile male performance in copulatory tests. Further studies will determine the feasibility of bacterial amelioration in SIT operations.

  6. Precocious sexual signalling and mating in Anastrepha fraterculus (Diptera: Tephritidae) sterile males achieved through juvenile hormone treatment and protein supplements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual maturation of Anastrepha fraterculus is a long process. Methoprene (a mimic of juvenile hormone) considerably reduces the time for sexual maturation in males. However, in other Anastrepha species, this effect depends on protein intake at the adult stage. Here, we evaluated the mating competit...

  7. 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...

  8. 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

  9. Male rat sexual behavior.

    PubMed

    Agmo, A

    1997-05-01

    The male rat's sexual behavior constitutes a highly ordered sequence of motor acts involving both striate and smooth muscles. It is spontaneously displayed by most adult made rats in the presence of a sexually receptive female. Although the behavior is important for the survival of the species it is not necessary for survival of the individual. In that way it is different from other spontaneous behaviors such as eating, drinking, avoidance of pain, respiration or thermoregulation. Among other things, this means that it is difficult to talk about sexual deprivation or need. Nevertheless, studies of male sex behavior distinguish sexual motivation (the ease by which behavior is activated, "libido") from the execution of copulatory acts (performance, "potency") (Meisel, R.L. and Sachs, B.D., The physiology of male sexual behavior. In: E. Knobil and J.D. Neill (Eds.), The Physiology of Reproduction, 2nd Edn., Vol. 2, Raven Press, New York, 1994, pp. 3-105 [13]). The hormonal control of male sexual behavior has been extensively studied. It is clear that steroid hormones, androgens and estrogens, act within the central nervous system, modifying neuronal excitability. The exact mechanism by which these hormones activate sex behavior remains largely unknown. However, there exists a considerable amount of knowledge concerning the brain structures important for sexual motivation and for the execution of sex behavior. The modulatory role of some non-steroid hormones is partly known, as well as the consequences of manipulations of several neurotransmitter systems.

  10. Sport and male sexuality.

    PubMed

    Sgrò, P; Di Luigi, L

    2017-03-22

    The relationships between sport and sexuality in males are of great social and clinical interest, because of sports and motor activities that highly promote social and sexual relationships. Even if few literature exist, two main questions should be taken into account: whether and how physical exercise and sport positively or negatively influence sexual health and behavior and/or whether and how sexual behavior may affect a sub-sequent sport performance. Physical exercise and sport per se can influence, positively or negatively, the hypothalamic-pituitary-testicular axis function and, consequently, the individual's reproductive and/or sexual health. This depends on individual factors such as genetic and epigenetic ones and on different variables involved in the practice of sport activities (type of sport, intensity and duration of training, doping and drug use and abuse, nutrition, supplements, psychological stress, allostatic load, etc.). If well conducted, motor and sport activities could have beneficial effects on sexual health in males. Among different lifestyle changes, influencing sexual health, regular physical activity is fundamental to antagonize the onset of erectile dysfunction (ED). However, competitive sport can lead both reproductive and/or sexual tract damages and dysfunctions, transient (genital pain, hypoesthesia of the genitalia, hypogonadism, DE, altered sexual drive, etc.) or permanent (hypogonadism, DE, etc.), by acting directly (traumas of the external genitalia, saddle-related disorders in cyclists, etc.) or indirectly (exercise-related hypogonadism, drug abuse, doping, stress, etc.). Sexual activities shortly performed before a sport competition could differently influence sport performance. Due to the few existing data, it is advisable to avoid an absolute pre-competition sexual abstinence.

  11. Molecular analysis of cytoplasmic male sterility

    SciTech Connect

    Hanson, M.R.

    1990-01-01

    The ultimate aims of the project are to understand the molecular mechanism of the disruption in pollen development which occurs in cytoplasmic male sterile plants and to understand the control of respiratory energy flow in the higher plant cell. A mitochondrial locus termed S-pcf segregates with sterility and with an alteration in respiration in Petunia. This cloned locus contains three genes, an abnormal fused gene termed pcf, a gene for a subunit of an NADH dehydrogenase complex, and a small ribosomal subunit protein. The pcf gene is comprised of partial sequences of ATPase subunit 9, cytochrome oxidase subunit II, and an unidentified reading frame. Components of the S-Pcf locus will be introduced into the nuclear of a fertile genotype under the control of appropriate regulatory signals, and polypeptide products of introduced genes will be directed to the mitochondrion with a transit peptide. By examining transgenic plants, we can determine what elements of the locus are critical for altered respiration or sterility. Such knowledge could explain how mitochondrial DNA affects pollen development in the large number of plant species which exhibit the agronomically important trait of male sterility. 10 refs., 3 figs.

  12. Development of male-sterile lines for breeding hybrid rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice is a self-pollinated crop that depends on male-sterility for F1 hybrid seed production. As an alternative to accessing existing male-sterile lines from other hybrid breeding programs, the program in Arkansas has created its own novel male-sterile sources. These were developed out of germplasm...

  13. Suppression of Pest Lepidoptera by Releasing Partially Sterile Males

    ERIC Educational Resources Information Center

    Knipling. E. F.

    1970-01-01

    Uses population growth models to calculate the theoretical suppression of reproduction achieved by releasing irradiated male moths carrying genetic sterility factors. Shows that releasing partially sterile males should be more effective than releasing fully sterile males. Discusses the costs and advantages of applying this approach to the control…

  14. 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.

  15. 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

  16. Cytoplasmic male sterility in Brassicaceae crops.

    PubMed

    Yamagishi, Hiroshi; Bhat, Shripad R

    2014-05-01

    Brassicaceae crops display strong hybrid vigor, and have long been subject to F1 hybrid breeding. Because the most reliable system of F1 seed production is based on cytoplasmic male sterility (CMS), various types of CMS have been developed and adopted in practice to breed Brassicaceae oil seed and vegetable crops. CMS is a maternally inherited trait encoded in the mitochondrial genome, and the male sterile phenotype arises as a result of interaction of a mitochondrial CMS gene and a nuclear fertility restoring (Rf) gene. Therefore, CMS has been intensively investigated for gaining basic insights into molecular aspects of nuclear-mitochondrial genome interactions and for practical applications in plant breeding. Several CMS genes have been identified by molecular genetic studies, including Ogura CMS from Japanese radish, which is the most extensively studied and most widely used. In this review, we discuss Ogura CMS, and other CMS systems, and the causal mitochondrial genes for CMS. Studies on nuclear Rf genes and the cytoplasmic effects of alien cytoplasm on general crop performance are also reviewed. Finally, some of the unresolved questions about CMS are highlighted.

  17. Male infertility: an obstacle to sexuality?

    PubMed

    Bechoua, S; Hamamah, S; Scalici, E

    2016-05-01

    Interactions between infertility and sexuality are numerous and complex. Infertile men may suffer from sexual dysfunction (SD) when undergoing an assisted reproductive technology programme. We undertook a review both in French and English of the available data on male SD when being diagnosed with a fertility problem with a specific focus on azoospermic men. The review was performed over a 30-year time period using PubMed/Medline. The sexual concerns and needs of infertile/sterile men for whom potential parenting can be compromised were evaluated. When diagnosed with infertility, men usually go through a crisis that can have a deleterious effect on their sexuality with sometimes a feeling of sexual inadequacy. Infertile men will feel stigmatized because they are perceived as being deficient in a specific component of their masculinity. Hence, subsequent SD may occur that can impact the couple sexuality and the infertility management. However, little is known on how the announcement of azoospermia may affect male on a sexual and psychological point of view. The present review suggests that a global management through a healthcare network (biologist, andrologist, sexologist and psychologist) is required which will allow to consider infertility and its subsequent sexual disorders as a whole and not as dichotomized issues.

  18. Puzzles in modern biology. I. Male sterility, failure reveals design.

    PubMed

    Frank, Steven A

    2016-01-01

    Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design.

  19. Puzzles in modern biology. I. Male sterility, failure reveals design

    PubMed Central

    Frank, Steven A.

    2016-01-01

    Many human males produce dysfunctional sperm. Various plants frequently abort pollen. Hybrid matings often produce sterile males. Widespread male sterility is puzzling. Natural selection prunes reproductive failure. Puzzling failure implies something that we do not understand about how organisms are designed. Solving the puzzle reveals the hidden processes of design. PMID:28004842

  20. Tropics accelerate the evolution of hybrid male sterility in Drosophila.

    PubMed

    Yukilevich, Roman

    2013-06-01

    Understanding the evolutionary mechanisms that facilitate speciation and explain global patterns of species diversity has remained a challenge for decades. The most general pattern of species biodiversity is the latitudinal gradient, whereby species richness increases toward the tropics. Although such a global pattern probably has a multitude of causes, recent attention has focused on the hypothesis that speciation and the evolution of reproductive isolation occur faster in the tropics. Here, I tested this prediction using a dataset on premating and postzygotic isolation between recently diverged Drosophila species. Results showed that while the evolution of premating isolation was not greater between tropical Drosophila relative to nontropical species, postzygotic isolation evolved faster in the tropics. In particular, hybrid male sterility was much greater among tropical Drosophila compared to nontropical species pairs of similar genetic age. Several testable explanations for the novel pattern are discussed, including greater role for sterility-inducing bacterial endosymbionts in the tropics and more intense sperm-sperm competition or sperm-egg sexual conflict in the tropics. The results imply that processes of speciation in the tropics may evolve at different rates or may even be somewhat different from those at higher latitudes.

  1. Transcriptional regulation of male-sterility in 7B-1 male-sterile tomato mutant

    PubMed Central

    Omidvar, Vahid; Mohorianu, Irina; Dalmay, Tamas; Zheng, Yi; Fei, Zhangjun; Pucci, Anna; Mazzucato, Andrea; Večeřová, Vendula; Sedlářova, Michaela; Fellner, Martin

    2017-01-01

    The 7B-1 tomato (Solanum lycopersicum L. cv Rutgers) is a male-sterile mutant with enhanced tolerance to abiotic stress, which makes it a potential candidate for hybrid seed breeding and stress engineering. To underline the molecular mechanism regulating the male-sterility in 7B-1, transcriptomic profiles of the 7B-1 male-sterile and wild type (WT) anthers were studied using mRNA sequencing (RNA-Seq). In total, 768 differentially expressed genes (DEGs) were identified, including 132 up-regulated and 636 down-regulated transcripts. Gene ontology (GO) enrichment analysis of DEGs suggested a general impact of the 7B-1 mutation on metabolic processes, such as proteolysis and carbohydrate catabolic process. Sixteen candidates with key roles in regulation of anther development were subjected to further analysis using qRT-PCR and in situ hybridization. Cytological studies showed several defects associated with anther development in the 7B-1 mutant, including unsynchronized anther maturation, dysfunctional meiosis, arrested microspores, defect in callose degradation and abnormal tapetum development. TUNEL assay showed a defect in programmed cell death (PCD) of tapetal cells in 7B-1 anthers. The present study provides insights into the transcriptome of the 7B-1 mutant. We identified several genes with altered expression level in 7B-1 (including beta-1,3 glucanase, GA2oxs, cystatin, cysteine protease, pectinesterase, TA29, and actin) that could potentially regulate anther developmental processes, such as meiosis, tapetum development, and cell-wall formation/degradation. PMID:28178307

  2. 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

  3. Sterilization.

    PubMed

    Peterson, Herbert B

    2008-01-01

    Worldwide, sterilization (tubal sterilization and vasectomy) is used by more people than any other method of contraception. All techniques of tubal sterilization in widespread use in the United States have low risks of surgical complications. Although tubal sterilization is highly effective, the risk of pregnancy varies by age and method of occlusion. Pregnancies can occur many years after the procedure, and when they do, the risk of ectopic gestation is high. There is now strong evidence against the existence of a post-tubal ligation syndrome of menstrual abnormalities. Although women who have undergone tubal sterilization are more likely than other women to undergo hysterectomy subsequently, there is no known biologic basis for this relationship. Although sterilization is intended to be permanent, expressions of regret and requests for reversal are not uncommon and are much more likely to occur among women sterilized at young ages. Tubal sterilization has little or no effect on sexual function for most women. Vasectomy is less likely than tubal sterilization to result in serious complications. Minor complications, however, are not uncommon. Vasectomy does not increase the risk of heart disease, and available evidence argues against an increase in the risk of prostate cancer, testicular cancer, or overall mortality. Whether a postvasectomy pain syndrome exists remains controversial. Although the long-term effectiveness of vasectomy is less well-studied than that for tubal sterilization, it seems likely to be at least as effective. Intrauterine devices and progestin implants are long-acting, highly effective alternatives to sterilization.

  4. Construction of a male sterility system for hybrid rice breeding and seed production using a nuclear male sterility gene

    PubMed Central

    Chang, Zhenyi; Chen, Zhufeng; Wang, Na; Xie, Gang; Lu, Jiawei; Yan, Wei; Zhou, Junli; Tang, Xiaoyan; Deng, Xing Wang

    2016-01-01

    The breeding and large-scale adoption of hybrid seeds is an important achievement in agriculture. Rice hybrid seed production uses cytoplasmic male sterile lines or photoperiod/thermo-sensitive genic male sterile lines (PTGMS) as female parent. Cytoplasmic male sterile lines are propagated via cross-pollination by corresponding maintainer lines, whereas PTGMS lines are propagated via self-pollination under environmental conditions restoring male fertility. Despite huge successes, both systems have their intrinsic drawbacks. Here, we constructed a rice male sterility system using a nuclear gene named Oryza sativa No Pollen 1 (OsNP1). OsNP1 encodes a putative glucose–methanol–choline oxidoreductase regulating tapetum degeneration and pollen exine formation; it is specifically expressed in the tapetum and miscrospores. The osnp1 mutant plant displays normal vegetative growth but complete male sterility insensitive to environmental conditions. OsNP1 was coupled with an α-amylase gene to devitalize transgenic pollen and the red fluorescence protein (DsRed) gene to mark transgenic seed and transformed into the osnp1 mutant. Self-pollination of the transgenic plant carrying a single hemizygous transgene produced nontransgenic male sterile and transgenic fertile seeds in 1:1 ratio that can be sorted out based on the red fluorescence coded by DsRed. Cross-pollination of the fertile transgenic plants to the nontransgenic male sterile plants propagated the male sterile seeds of high purity. The male sterile line was crossed with ∼1,200 individual rice germplasms available. Approximately 85% of the F1s outperformed their parents in per plant yield, and 10% out-yielded the best local cultivars, indicating that the technology is promising in hybrid rice breeding and production. PMID:27864513

  5. Modeling the suppression of sea lamprey populations by the release of sterile males or sterile females

    USGS Publications Warehouse

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

    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 the SFRT) the rate of polygyny. Releasing sterile males reduced populations more quickly than did the release of sterile females. For a population in which 30% are trapped, sterile animals are initially released at ratio of 10 sterile to 1 fertile animal, 5 adult progeny are produced per fertile mating, 60% are male, and males mate with an average of 1.65 females, the initial population is reduced 87% by SMRT and 68% by SFRT in one generation. The extent of suppression achieved is most sensitive to changes in the initial sterile release ratio. Given the current status of sea lamprey populations and trapping operations in the Great Lakes, the sterile-male-release technique has the best chance for success on a lake-wide basis if implemented in Lake Michigan. The effectiveness of the sterile-female-release technique should be investigated in a controlled study. Advancing trapping technology should be a high priority in the near term, and artificial rearing of sea lampreys to the adult stage should be a high priority in the long term. The diligent pursuit of sea lamprey suppression over a period of several decades can be expected to yield great benefits.

  6. [Brain mechanisms of male sexual function].

    PubMed

    Wang, Ying; Dou, Xin; Li, Jun-Fa; Luo, Yan-Lin

    2011-08-01

    In this paper, we reviewed the brain imaging studies of male sexual function in recent years from three aspects: the brain mechanism of normal sexual function, the brain mechanism of sexual dysfunction, and the mechanism of drug therapy for sexual dysfunction. Studies show that the development stages of male sexual activities, such as the excitement phase, plateau phase and orgasm phase, are controlled by different neural networks. The mesodiencephalic transition zone may play an important role in the start up of male ejaculation. There are significant differences between sexual dysfunction males and normal males in activation patterns of the brain in sexual arousal. The medial orbitofrontal cortex and inferior frontal gyrus in the abnormal activation pattern are correlated with sexual dysfunction males in sexual arousal. Serum testosterone and morphine are commonly used drugs for male sexual dysfunction, whose mechanisms are to alter the activating levels of the medial orbitofrontal cortex, insula, claustrum and inferior temporal gyrus.

  7. Comparative Transcriptome Analysis of Recessive Male Sterility (RGMS) in Sterile and Fertile Brassica napus Lines

    PubMed Central

    Zhao, Huiyan; Liu, Chuan; Li, Jiana; Tang, Zhanglin; Xu, Xinfu; Qiu, Xiao; Wang, Rui; Lu, Kun

    2015-01-01

    The recessive genetic male sterility (RGMS) system plays a key role in the production of hybrid varieties in self-pollinating B. napus plants, and prevents negative cytoplasmic effects. However, the complete molecular mechanism of the male sterility during male-gametogenesis in RGMS remains to be determined. To identify transcriptomic changes that occur during the transition to male sterility in RGMS, we examined the male sterile line WSLA and male fertile line WSLB, which are near-isogenic lines (NILs) differing only in the fertility trait. We evaluated the phenotypic features and sterility stage using anatomical analysis. Comparative RNA sequencing analysis revealed that 3,199 genes were differentially expressed between WSLA and WSLB. Many of these genes are mainly involved in biological processes related to flowering, including pollen tube development and growth, pollen wall assembly and modification, and pollen exine formation and pollination. The transcript profiles of 93 genes associated with pollen wall and anther development were determined by quantitative RT-PCR in different flower parts, and classified into the following three major clades: 1) up-regulated in WSLA plants; 2) down-regulated in WSLA plants; and 3) down-regulated in buds, but have a higher expression in stigmas of WSLA than in WSLB. A subset of genes associated with sporopollenin accumulation were all up-regulated in WSLA. An excess of sporopollenin results in defective pollen wall formation, which leads to male sterility in WSLA. Some of the genes identified in this study are candidates for future research, as they could provide important insight into the molecular mechanisms underlying RGMS in WSLA. PMID:26656530

  8. 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

  9. Bactrocera dorsalis male sterilization by targeted RNA interference of spermatogenesis: empowering sterile insect technique programs

    PubMed Central

    Dong, Yong-Cheng; Wang, Zhi-Jian; Chen, Zhen-Zhong; Clarke, Anthony R.; Niu, Chang-Ying

    2016-01-01

    RNA interference (RNAi) is a genetic technique which has novel application for sustainable pest control. The Sterile Insect Technique (SIT) uses releases of mass-produced, sterile male insects to out-compete wild males for mates to reduce pest populations. RNAi sterilization of SIT males would have several advantages over radiation sterilization, but to achieve this appropriate target genes must first be identified and then targeted with interference technology. With this goal, eight spermatogenesis related candidate genes were cloned and tested for potential activity in Bactrocera dorsalis. The knockdown of candidate genes by oral delivery of dsRNAs did not influence the mating of male flies, but significantly affected the daily average number of eggs laid by females, and reduced egg hatching rate by 16–60%. RNAi negatively affected spermatozoa quantitatively and qualitatively. Following the mating of lola-/topi-/rac-/rho-/upd-/magu-silenced males, we recorded a significant decrease in number and length of spermatozoa in female spermatheca compared to gfp-silenced control group. In a greenhouse trial, the number of damaged oranges and B. dorsalis larvae were significantly reduced in a dsrho-treated group compared with the dsgfp group. This study provides strong evidence for the use RNAi in pest management, especially for the improvement of SIT against B. dorsalis and other species. PMID:27767174

  10. Bactrocera dorsalis male sterilization by targeted RNA interference of spermatogenesis: empowering sterile insect technique programs.

    PubMed

    Dong, Yong-Cheng; Wang, Zhi-Jian; Chen, Zhen-Zhong; Clarke, Anthony R; Niu, Chang-Ying

    2016-10-21

    RNA interference (RNAi) is a genetic technique which has novel application for sustainable pest control. The Sterile Insect Technique (SIT) uses releases of mass-produced, sterile male insects to out-compete wild males for mates to reduce pest populations. RNAi sterilization of SIT males would have several advantages over radiation sterilization, but to achieve this appropriate target genes must first be identified and then targeted with interference technology. With this goal, eight spermatogenesis related candidate genes were cloned and tested for potential activity in Bactrocera dorsalis. The knockdown of candidate genes by oral delivery of dsRNAs did not influence the mating of male flies, but significantly affected the daily average number of eggs laid by females, and reduced egg hatching rate by 16-60%. RNAi negatively affected spermatozoa quantitatively and qualitatively. Following the mating of lola-/topi-/rac-/rho-/upd-/magu-silenced males, we recorded a significant decrease in number and length of spermatozoa in female spermatheca compared to gfp-silenced control group. In a greenhouse trial, the number of damaged oranges and B. dorsalis larvae were significantly reduced in a dsrho-treated group compared with the dsgfp group. This study provides strong evidence for the use RNAi in pest management, especially for the improvement of SIT against B. dorsalis and other species.

  11. 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...

  12. A New Adult Diet Formulation for Sterile Males of Anastrepha ludens and Anastrepha obliqua (Diptera: Tephritidae).

    PubMed

    Orozco-Dávila, Dina; Quintero-Fong, Luis

    2015-08-01

    A new adult diet formulation was evaluated for sterile Anastrepha ludens (Loew) and Anastrepha obliqua (Macquart) males at the emergence and release facility of fruit flies in Mexico. The formulation consists of hydrolyzed protein, sugar, juvenile hormone analogue methoprene, and water. The proportion of the ingredients between the solute (4% hydrolyzed protein and 96% sugar) and solvent (10% methoprene and 90% water) was 5:1. This new formulation was called the 1:24 formulation. The main objectives of this study were to develop a simple way to supply the 1:24 formulation to adults and to compare the sexual performance of these flies with the performance of flies fed a standard diet (called the Mubarqui formulation) used at the emergence and release facility of fruit flies in Mexico. The preparation, time, and cost also were evaluated. The results showed no significant differences in the sexual behaviors of the males (number of males mating, number of males calling, mating latency, and mating duration) between the 1:24 formulation and the Mubarqui formulation. However, the cost and the required preparation time are much lower for the 1:24 formulation process than for the Mubarqui formulation process. Based on these results, we recommend the 1:24 formulation as an additional adult diet option in the handling of sterile flies. Its application is practical and does not require changes in packaging systems. The contribution of our findings and their potential application to the improvement of the sterile insect technique are discussed.

  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. Genetics and evolution of hybrid male sterility in house mice.

    PubMed

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

    2012-07-01

    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 F(2) 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 F(2) 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.

  15. [Calcium distribution in fertile and sterile anthers of a genic male sterile Chinese cabbage].

    PubMed

    Xie, Chao-Tian; Yang, Yan-Hong; Qiu, Yi-Lan; Ge, Li-Li; Tian, Hui-Qiao

    2005-12-01

    Potassium antimonite was used to locate calcium in the fertile and sterile anthers of a genic male sterile Chinese cabbage (Brassica campestris L. ssp. chinensis Makino) to probe the relation between Ca(2+) and fertility and sterility of anthers of the cabbage. During fertile anther development, calcium granules increase in number in anther wall cells after meiosis, and then appeared also in locule, suggesting a calcium influx into locule from anther wall cells (Plate I-4). Then the number of calcium granules in microspore cytoplasm also increased at early stage (Plate II-1), accumulated mainly on the membrane of small vacuoles which were fusing to form big ones to make a polarity in the cell and to prepare asymmetric division of microspore (Plate II-3,4). After microspore division and the big vacuole decomposition, many calcium granules accumulated again on the membrane of the vacuoles (Plate III-1,2), displaying calcium regulates vacuole formation and decomposition during pollen development. In sterile anthers, abnormal distribution of calcium granules first appeared in callus wall of microspore mother cell (Plate IV-1). However, only a few calcium granules appeared in early microspores, which then could not form small vacuoles and finally a big vacuole (Plate IV-2,3). The aborting microspores degenerate by cytoplasm shrinking (Plate IV-5,6). The difference pattern of distribution of calcium granules between the fertile and sterile anthers indicates that anomalies in the distribution of calcium accumulation are correlated with the failure of pollen development and pollen abortion.

  16. Progress in development of male sterile germplasm for hybrid rice breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Currently, there are two types of male sterility mainly commercialized in hybrid rice production, three-line type or cytoplasmic male sterility (CMS) and two-line type or environmental male sterility (EMS). The great majority belongs to the CMS and there are four strategies that have been proven suc...

  17. 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

  18. Male-Female Sexuality: An Annotated Bibliography.

    ERIC Educational Resources Information Center

    Wilson, Janice

    This annotated bibliography contains over 500 sources on the historical and contemporary development and expression of male and female sexuality. There are 68 topic headings which provide easy access for subject areas. A major portion of the bibliography is devoted to contemporary male-female sexuality. These materials consist of research findings…

  19. Mitochondrion role in molecular basis of cytoplasmic male sterility.

    PubMed

    Horn, Renate; Gupta, Kapuganti J; Colombo, Noemi

    2014-11-01

    Cytoplasmic male sterility and its fertility restoration via nuclear genes offer the possibility to understand the role of mitochondria during microsporogenesis. In most cases rearrangements in the mitochondrial DNA involving known mitochondrial genes as well as unknown sequences result in the creation of new chimeric open reading frames, which encode proteins containing transmembrane domains. So far, most of the CMS systems have been characterized via restriction fragment polymorphisms followed by transcript analysis. However, whole mitochondrial genome sequence analyses comparing male sterile and fertile cytoplasm open options for deeper insights into mitochondrial genome rearrangements. We more and more start to unravel how mitochondria are involved in triggering death of the male reproductive organs. Reduced levels of ATP accompanied by increased concentrations of reactive oxygen species, which are produced more under conditions of mitochondrial dysfunction, seem to play a major role in the fate of pollen production. Nuclear genes, so called restorer-of-fertility are able to restore the male fertility. Fertility restoration can occur via pentatricopeptide repeat (PPR) proteins or via different mechanisms involving non-PPR proteins.

  20. Programmed cell death promotes male sterility in the functional dioecious Opuntia stenopetala (Cactaceae)

    PubMed Central

    Flores-Rentería, Lluvia; Orozco-Arroyo, Gregorio; Cruz-García, Felipe; García-Campusano, Florencia; Alfaro, Isabel; Vázquez-Santana, Sonia

    2013-01-01

    Background and Aims The sexual separation in dioecious species has interested biologists for decades; however, the cellular mechanism leading to unisexuality has been poorly understood. In this study, the cellular changes that lead to male sterility in the functionally dioecious cactus, Opuntia stenopetala, are described. Methods The spatial and temporal patterns of programmed cell death (PCD) were determined in the anthers of male and female flowers using scanning electron microscopy analysis and histological observations, focusing attention on the transition from bisexual to unisexual development. In addition, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling assays were used as an indicator of DNA fragmentation to corroborate PCD. Key results PCD was detected in anthers of both female and male flowers, but their patterns differed in time and space. Functionally male individuals developed viable pollen, and normal development involved PCD on each layer of the anther wall, which occurred progressively from the inner (tapetum) to the outer layer (epidermis). Conversely, functional female individuals aborted anthers by premature and displaced PCD. In anthers of female flowers, the first signs of PCD, such as a nucleus with irregular shape, fragmented and condensed chromatin, high vacuolization and condensed cytoplasm, occurred at the microspore mother cell stage. Later these features were observed simultaneously in all anther wall layers, connective tissue and filament. Neither pollen formation nor anther dehiscence was detected in female flowers of O. stenopetala due to total anther disruption. Conclusions Temporal and spatial changes in the patterns of PCD are responsible for male sterility of female flowers in O. stenopetala. Male fertility requires the co-ordination of different events, which, when altered, can lead to male sterility and to functionally unisexual individuals. PCD could be a widespread mechanism in the determination of

  1. 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

  2. Genetic studies on cytoplasmic male sterility in maize

    SciTech Connect

    Laughnan, J.R.

    1992-01-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  3. 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…

  4. Effects of surgical and chemical sterilization on the behavior of free-roaming male dogs in Puerto Natales, Chile.

    PubMed

    Garde, E; Pérez, G E; Vanderstichel, R; Dalla Villa, P F; Serpell, J A

    2016-01-01

    Population management of free-roaming domestic dogs (Canis lupus familiaris) is of interest due to the threat these animals pose to people, other animals and the environment. Current sterilization procedures for male dogs include surgical and chemical methods. However, little is known about how these procedures affect their behavior. The primary objective of this study was to investigate changes in selected behaviors following chemical and surgical sterilization in a male free-roaming dog (FRD) population in southern Chile. We also examined the association between serum testosterone levels and behaviors thought to be influenced by circulating androgens. A total of 174 dogs were randomly assigned to either a surgical or chemical sterilization group, or a control group. At the onset of the intervention period, 119 dogs remained and 102 dogs successfully completed the study. Each dog was monitored pre- and post-intervention using video recordings, GPS collars, and blood samples for the measurement of testosterone. Analysis of behavior revealed that surgically castrated dogs showed no reduction of sexual activity or aggression when compared to their pre-intervention behavior. Chemically sterilized dogs showed a statistically significant increase in dog-directed aggression, but no change in sexual activity. There was no change in home range size in any groups between the pre- and post-intervention measurement. We found no consistent association between levels of serum testosterone concentration and behavioral changes in any of the groups. This study presents the first detailed behavioral observations following surgical and chemical sterilization in male FRDs. The information generated is highly relevant to communities struggling with the control of FRDs. Complementary studies to further our understanding of the effects of male sterilization on the behavioral and reproductive dynamics of FRD populations are needed.

  5. 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.

  6. Auxins reverse plant male sterility caused by high temperatures

    PubMed Central

    Sakata, Tadashi; Oshino, Takeshi; Miura, Shinya; Tomabechi, Mari; Tsunaga, Yuta; Higashitani, Nahoko; Miyazawa, Yutaka; Takahashi, Hideyuki; Watanabe, Masao; Higashitani, Atsushi

    2010-01-01

    With global warming, plant high temperature injury is becoming an increasingly serious problem. In wheat, barley, and various other commercially important crops, the early phase of anther development is especially susceptible to high temperatures. Activation of auxin biosynthesis with increased temperatures has been reported in certain plant tissues. In contrast, we here found that under high temperature conditions, endogenous auxin levels specifically decreased in the developing anthers of barley and Arabidopsis. In addition, expression of the YUCCA auxin biosynthesis genes was repressed by increasing temperatures. Application of auxin completely reversed male sterility in both plant species. These findings suggest that tissue-specific auxin reduction is the primary cause of high temperature injury, which leads to the abortion of pollen development. Thus, the application of auxin may help sustain steady yields of crops despite future climate change. PMID:20421476

  7. Auxins reverse plant male sterility caused by high temperatures.

    PubMed

    Sakata, Tadashi; Oshino, Takeshi; Miura, Shinya; Tomabechi, Mari; Tsunaga, Yuta; Higashitani, Nahoko; Miyazawa, Yutaka; Takahashi, Hideyuki; Watanabe, Masao; Higashitani, Atsushi

    2010-05-11

    With global warming, plant high temperature injury is becoming an increasingly serious problem. In wheat, barley, and various other commercially important crops, the early phase of anther development is especially susceptible to high temperatures. Activation of auxin biosynthesis with increased temperatures has been reported in certain plant tissues. In contrast, we here found that under high temperature conditions, endogenous auxin levels specifically decreased in the developing anthers of barley and Arabidopsis. In addition, expression of the YUCCA auxin biosynthesis genes was repressed by increasing temperatures. Application of auxin completely reversed male sterility in both plant species. These findings suggest that tissue-specific auxin reduction is the primary cause of high temperature injury, which leads to the abortion of pollen development. Thus, the application of auxin may help sustain steady yields of crops despite future climate change.

  8. Parthenogenesis maintains male sterility in a gynodioecious orchid.

    PubMed

    Huang, Shuang-Quan; Lu, Yang; Chen, Ying-Zhuo; Luo, Yi-Bo; Delph, Lynda F

    2009-10-01

    The invasion of male-sterile (female) individuals into hermaphroditic populations, leading to gynodioecy, is common in flowering plants. Both theoretical and empirical studies have shown that as the frequency of females increases in a population, pollen limitation reduces seed production more in females than in hermaphrodites, leading to higher fitness for hermaphrodites and a consequent decrease in female frequency. Here we show that contrary to this expectation, females of the gynodioecious orchid Satyrium ciliatum are maintained only in populations that experience high pollen limitation caused by low pollinator service and high pollen herbivory. This species avoids the typical problem of pollen limitation for seed production and can therefore maintain high frequencies of females in pollen-limited populations because females produce more seeds than hermaphrodites via facultative parthenogenesis in the absence of pollinia. Our results therefore demonstrate that parthenogenesis is a novel mechanism favoring the maintenance of gynodioecy.

  9. Effect of normative masculinity on males' dysfunctional sexual beliefs, sexual attitudes, and perceptions of sexual functioning.

    PubMed

    Clarke, Michael J; Marks, Anthony D G; Lykins, Amy D

    2015-01-01

    Male sexual dysfunction is a prevalent and distressing condition, which may be exacerbated by the sufferer's perceptions of masculinity and normative sexual behavior. This study sought to investigate the effect of social context on males' beliefs regarding sexual behavior. The research examined the effect of male role modeling and masculine cues on males' dysfunctional sexual beliefs, sexual attitudes, and self-perceptions of sexual functioning. A sample of 140 male participants, with a mean age of 29 years, was exposed to pictorial and verbal cues that presented different versions of male behavior across three conditions. Results indicated that males exposed to models and cues of traditional masculinity showed significantly increased levels of dysfunctional sexual beliefs and traditional sexual attitudes relative to males exposed to models of modern masculinity. Results also indicated that males exposed to traditional masculine stimuli reported lower levels of sexual inhibition due to fear of performance failure than males exposed to models of modern masculinity. The potential role of social context is discussed in the development and maintenance of male sexual dysfunction and its implications for treatment.

  10. Influence of Methoprene on Pheromone Emission and Sexual Maturation of Anastrepha obliqua (Diptera: Tephritidae) males.

    PubMed

    Muñoz-Barrios, Rodolfo; Cruz-López, Leopoldo; Rojas, Julio C; Hernández, Emilio; Liedo, Pablo; Gómez-Simuta, Yeudiel; Malo, Edi A

    2016-04-01

    It has been demonstrated that the application of juvenile hormone analog, methoprene, reduces the time required for sexual maturation and enhances mating success in several species of tephritid fruit flies. This study examined the effect of different concentrations of methoprene incorporated into the diet of adult flies and distinct sugar:protein (S:P) ratios on sexual maturity and pheromone emission of Anastrepha obliqua males. Diets with 0.2 and 0.5% of methoprene accelerated sexual maturation of males compared with untreated males. In subsequent assays, the enhancement of male pheromone emission and sexual maturation by the incorporation of 0.02% methoprene into a 24:1 (S: P) diet was confirmed. Among the volatiles released by males, (Z)-3-nonenol and (Z,Z)-3,6-nonadienol were emitted at higher quantities by flies treated with methoprene than untreated ones. The results show that methoprene accelerates sexual maturation of mass-reared A. obliqua males and increases their mating propensity. This would reduce the time required to attain sexual maturation by sterile males, thus decreasing fly handling costs and improving the efficacy of the sterile insect technique.

  11. Sterilizing effects of cobalt-60 and cesium-137 radiation on male sea lampreys

    USGS Publications Warehouse

    Hanson, L.H.

    1990-01-01

    Male spawning-run sea lampreys Petromyzon marinus were exposed to various doses of cobalt-60 or cesium-137 radiation in an attempt to sterilize them for use in a program for controlling sea lampreys through the release of sterile males. Males captured and irradiated during the early part of the upstream migration were not effectively sterilized at the doses tested. After irradiation, the sea lampreys were more susceptible to fungal infections by Saprolegnia sp., and many died without attempting to spawn. Males captured and irradiated during the middle and late parts of the spawning migration were effectively sterilized at a dose of 2,000 rads. However, some radiation-induced mortality was observed in males captured and irradiated during the middle part of the spawning migration. Radiation is not as effective as the chemosterilant bisazir for sterilizing male sea lampreys.

  12. Psychopharmacology of male rat sexual behavior: modeling human sexual dysfunctions?

    PubMed

    Olivier, B; Chan, J S W; Pattij, T; de Jong, T R; Oosting, R S; Veening, J G; Waldinger, M D

    2006-01-01

    Most of our current understanding of the neurobiology, neuroanatomy and psychopharmacology of sexual behavior and ejaculatory function has been derived from preclinical studies in the rat. When a large population of male rats is tested on sexual activity during a number of successive tests, over time individual rats display a very stable sexual behavior that is either slow, normal or fast as characterized by the number of ejaculations performed. These sexual endophenotypes are postulated as rat counterparts of premature (fast rats) or retarded ejaculation (slow rats). Psychopharmacology in these endophenotypes helps to delineate the underlying mechanisms and pathology. This is illustrated by the effects of serotonergic antidepressants and serotonergic compounds on sexual and ejaculatory behavior of rats. These preclinical studies and models contribute to a better understanding of the neurobiology of ejaculation and boost the development of novel drug targets to treat ejaculatory disorders such as premature and retarded ejaculation.

  13. Sexual functioning of male anabolic steroid abusers.

    PubMed

    Moss, H B; Panzak, G L; Tarter, R E

    1993-02-01

    The effects of anabolic steroid use on male sexual behavior were assessed using a structured clinical interview administered to male body builders currently using steroids, and to two comparison groups (body builders with a past but not current history of steroid use, and a group of "natural" body builders who had never used steroids). Current anabolic steroid users had a significantly higher coital and orgasmic frequency than did comparison athletes. They also reported a significantly higher incidence of erectile difficulties during the past month. Beliefs concerning the sexually stimulating effects of steroids did not correlate with the frequencies of specific sexual behaviors. The data support the contention that anabolic steroids, as androgenic compounds, enhance sexual desire.

  14. DNA methylation affected by male sterile cytoplasm in rice (Oryza sativa L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male sterile cytoplasm plays an important role in hybrid rice and cytoplasmic effects are sufficiently documented. However, no reports are available on DNA methylation affected by male sterile cytoplasm in hybrid rice. We used a methylation sensitive amplified polymorphism (MSAP) technique to charac...

  15. Diverse germplasm to devleop male-sterile lines for hybrid breeding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybrid rice breeding in the US has depended largely upon male-sterile lines originating in China or from other Asian sources. By contrast, the program in Arkansas has developed all of its male-sterile lines at Stuttgart,AR using germplasm accessions available in the USDA Rice Germplasm Collection st...

  16. Hybridization using cytoplasmic male sterility and herbicide tolerance from nuclear genes

    SciTech Connect

    Beversdorf, W.D.; Erickson, L.R.; Grant, I.

    1987-04-14

    An improved process is described for producing a substantially homogeneous population of plants of a predetermined hybrid variety of a crop which is capable of undergoing both self-pollination and cross-pollination. This process comprises: growing in a first planting area a substantially random population of cytoplasmic male sterile plants which exhibit tolerance to at least one herbicide attributable solely to homozygous dominant nuclear genes, and male fertile plants which are capable of pollinating the cytoplasmic male sterile plants and which lack the herbicide tolerance because the presence of homozygous recessive nuclear genes for such trait. The cytoplasmic male sterile plants and the male fertile plants are pollinated with pollen derived from the male fertile plants. Seed is formed on the cytoplasmic male sterile plants and on the male fertile plants. Harvesting in bulk the seed is formed on the plants of the first planting area.

  17. Psychosocial factors associated with male sexual difficulties.

    PubMed

    McCabe, Marita P; Connaughton, Catherine

    2014-01-01

    The role of medical conditions, childhood experiences, and psychological and relationship factors in the development and maintenance of male sexual difficulties is not well understood. Using self-report questionnaires, the current study examined how these factors are associated with male sexual difficulties overall, as well as for each of four separate problems (low sexual desire, erectile difficulties, premature ejaculation, delayed ejaculation). The participants for the study were 331 Australian men from the general population, all of whom were in cohabiting heterosexual relationships and had experienced one or more of the aforementioned sexual problems. Data were collected via an online survey between January 2010 and April 2011. The results demonstrated that medical factors as well as current psychological factors (e.g., performance anxiety) were most likely associated with each male sexual difficulty. These findings are in contrast to those obtained with women, where relationship factors are strongly related to female sexual problems. They would suggest that the targets for sex therapy may be different for men and women, with medical problems and performance anxiety being the primary targets for men.

  18. 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

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

    USGS Publications Warehouse

    Bergstedt, Roger A.; McDonald, Rodney B.; Twohey, Michael B.; Mullett, Katherine M.; Young, Robert J.; Heinrich, John 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.

  20. Genetic determination of male sterility in gynodioecious Silene nutans

    PubMed Central

    Garraud, C; Brachi, B; Dufay, M; Touzet, P; Shykoff, J A

    2011-01-01

    Gynodioecy, the coexistence of female and hermaphrodite plants within a species, is often under nuclear–cytoplasmic sex determination, involving cytoplasmic male sterility (CMS) genes and nuclear restorers. A good knowledge of CMS and restorer polymorphism is essential for understanding the evolution and maintenance of gynodioecy, but reciprocal crossing studies remain scarce. Although mitochondrial diversity has been studied in a few gynodioecious species, the relationship between mitotype diversity and CMS status is poorly known. From a French sample of Silene nutans, a gynodioecious species whose sex determination remains unknown, we chose the four most divergent mitotypes that we had sampled at the cytochrome b gene and tested by reciprocal crosses whether they carry distinct CMS genes. We show that gynodioecy in S. nutans is under nuclear–cytoplasmic control, with at least two different CMSs and up to four restorers with epistatic interactions. Female occurrence and frequency were highly dependent on the mitotype, suggesting that the level of restoration varies greatly among CMSs. Two of the mitotypes, which have broad geographic distributions, represent different CMSs and are very unequally restored. We discuss the dynamics of gynodioecy at the large-scale meta-population level. PMID:20808324

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

    PubMed

    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

    2008-12-02

    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.

  2. The Contribution of the Y Chromosome to Hybrid Male Sterility in House Mice

    PubMed Central

    Campbell, Polly; Good, Jeffrey M.; Dean, Matthew D.; Tucker, Priscilla K.; Nachman, Michael W.

    2012-01-01

    Hybrid sterility in the heterogametic sex is a common feature of speciation in animals. In house mice, the contribution of the Mus musculus musculus X chromosome to hybrid male sterility is large. It is not known, however, whether F1 male sterility is caused by X–Y or X-autosome incompatibilities or a combination of both. We investigated the contribution of the M. musculus domesticus Y chromosome to hybrid male sterility in a cross between wild-derived strains in which males with a M. m. musculus X chromosome and M. m. domesticus Y chromosome are partially sterile, while males from the reciprocal cross are reproductively normal. We used eight X introgression lines to combine different X chromosome genotypes with different Y chromosomes on an F1 autosomal background, and we measured a suite of male reproductive traits. Reproductive deficits were observed in most F1 males, regardless of Y chromosome genotype. Nonetheless, we found evidence for a negative interaction between the M. m. domesticus Y and an interval on the M. m. musculus X that resulted in abnormal sperm morphology. Therefore, although F1 male sterility appears to be caused mainly by X-autosome incompatibilities, X–Y incompatibilities contribute to some aspects of sterility. PMID:22595240

  3. Masculinity and male sexual behaviour in Mozambique.

    PubMed

    Macia, Manuel; Maharaj, Pranitha; Gresh, Ashley

    2011-11-01

    Like many countries in sub-Saharan Africa, Mozambique is facing a severe HIV epidemic. Evidence suggests that male sexual behaviour is one of the driving forces behind the epidemic. Yet, there is limited understanding of how notions of masculinity influence such behaviour in the context of HIV. Using data collected through focus group discussions and in-depth interviews with sexually active men and women, this paper investigates how notions of masculinity influence the risk of HIV infection among men. The study findings suggest that traditional norms of masculinity, the man as the main provider and figure of authority, continue to exert a strong influence on male attitudes and behaviour. Alternative approaches are urgently needed in HIV programming that take into consideration notions of masculinity in order to reduce risky sexual behaviour.

  4. Molecular mapping of a new induced gene for nuclear male sterility in sunflower (Helianthus annuus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new NMS line, NMS HA89-872, induced by mitomycin C and streptomycin carries a single recessive male-sterile gene ms6. An F2 population of 88 plants was obtained from a cross between nuclear male-sterile mutant NMS HA89-872 (msms) and male-fertile line RHA271 (MsMs). 225 SSR primers and 9 RFLP-deri...

  5. X-ray-induced sterility in Aedes albopictus (Diptera: Culicidae) and male longevity following irradiation.

    PubMed

    Yamada, H; Parker, A G; Oliva, C F; Balestrino, F; Gilles, J R L

    2014-07-01

    The mosquito Aedes albopictus (Skuse, 1895) is a potent vector of several arboviral diseases, most notably chikungunya and dengue fever. In the context of the sterile insect technique (SIT), the sterilization of the male mosquitoes before their release can be achieved by gamma-ray irradiation. As gamma-ray irradiators are becoming increasingly problematic to purchase and transport, the suitability of an X-ray irradiator as an alternative for the sterilization of Ae. albopictus males was studied. The sterilization of up to 200,000 pupae at one time can be achieved with relative ease, and the sterility results obtained were comparable with those achieved by gamma irradiation, where 99% sterility is induced with a dose of 40 Gy. A significant reduction of longevity was observed in the latter stages of the males' life after irradiation treatments, especially at doses > 40 Gy, which is consistent with the negative effects on longevity induced by similar radiation doses using gamma rays. Females irradiated at 40 Gy were not only 100% sterile, but also failed to oviposit entirely, i.e., all of the females laid 0 eggs. Overall, it was found that the X-ray irradiator is generally suitable for the sterilization process for sterile insect technique programs, as it showed a high processing capacity, practicality, high effectiveness, and reproducibility.

  6. Research to support sterile-male-release and genetic alteration techniques for sea lamprey control

    USGS Publications Warehouse

    Bergstedt, Roger A.; Twohey, Michael B.

    2007-01-01

    Integrated pest management of sea lampreys in the Laurentian Great Lakes has recently been enhanced by addition of a sterile-male-release program, and future developments in genetic approaches may lead to additional methods for reducing sea lamprey reproduction. We review the development, implementation, and evaluation of the sterile-male-release technique (SMRT) as it is being applied against sea lampreys in the Great Lakes, review the current understanding of SMRT efficacy, and identify additional research areas and topics that would increase either the efficacy of the SMRT or expand its geographic potential for application. Key areas for additional research are in the sterilization process, effects of skewed sex ratios on mating behavior, enhancing attractiveness of sterilized males, techniques for genetic alteration of sea lampreys, and sources of animals to enhance or expand the use of sterile lampreys.

  7. Sexually antagonistic selection in human male homosexuality.

    PubMed

    Camperio Ciani, Andrea; Cermelli, Paolo; Zanzotto, Giovanni

    2008-06-18

    Several lines of evidence indicate the existence of genetic factors influencing male homosexuality and bisexuality. In spite of its relatively low frequency, the stable permanence in all human populations of this apparently detrimental trait constitutes a puzzling 'Darwinian paradox'. Furthermore, several studies have pointed out relevant asymmetries in the distribution of both male homosexuality and of female fecundity in the parental lines of homosexual vs. heterosexual males. A number of hypotheses have attempted to give an evolutionary explanation for the long-standing persistence of this trait, and for its asymmetric distribution in family lines; however a satisfactory understanding of the population genetics of male homosexuality is lacking at present. We perform a systematic mathematical analysis of the propagation and equilibrium of the putative genetic factors for male homosexuality in the population, based on the selection equation for one or two diallelic loci and Bayesian statistics for pedigree investigation. We show that only the two-locus genetic model with at least one locus on the X chromosome, and in which gene expression is sexually antagonistic (increasing female fitness but decreasing male fitness), accounts for all known empirical data. Our results help clarify the basic evolutionary dynamics of male homosexuality, establishing this as a clearly ascertained sexually antagonistic human trait.

  8. Sexually Antagonistic Selection in Human Male Homosexuality

    PubMed Central

    Camperio Ciani, Andrea; Cermelli, Paolo; Zanzotto, Giovanni

    2008-01-01

    Several lines of evidence indicate the existence of genetic factors influencing male homosexuality and bisexuality. In spite of its relatively low frequency, the stable permanence in all human populations of this apparently detrimental trait constitutes a puzzling ‘Darwinian paradox’. Furthermore, several studies have pointed out relevant asymmetries in the distribution of both male homosexuality and of female fecundity in the parental lines of homosexual vs. heterosexual males. A number of hypotheses have attempted to give an evolutionary explanation for the long-standing persistence of this trait, and for its asymmetric distribution in family lines; however a satisfactory understanding of the population genetics of male homosexuality is lacking at present. We perform a systematic mathematical analysis of the propagation and equilibrium of the putative genetic factors for male homosexuality in the population, based on the selection equation for one or two diallelic loci and Bayesian statistics for pedigree investigation. We show that only the two-locus genetic model with at least one locus on the X chromosome, and in which gene expression is sexually antagonistic (increasing female fitness but decreasing male fitness), accounts for all known empirical data. Our results help clarify the basic evolutionary dynamics of male homosexuality, establishing this as a clearly ascertained sexually antagonistic human trait. PMID:18560521

  9. On Sexual Apathy in the Male

    PubMed Central

    Greenson, Ralph R.

    1968-01-01

    Ever since World War II, there has been a noticeable change in the sexual behavior and responses in men and women. Women, in general, are becoming sexually more assertive and demanding and men more indifferent and lethargic. In patients of middle age, sexual boredom is particularly pronounced in men, whereas the post-menopausal female becomes more interested in sexual pleasure. In the youth of the “cool” generation, both boys and girls are quite open about sex, but their sexual activities precede emotional involvement. The similarities in dress and behavior of both sexes indicate a wish for a twin rather than a search for a lover. In the age group between 25 and 45, women demand equal orgasms since they have become economically independent and are relatively free of the fear of pregnancy. This seems to have mobilized a deep-seated unconscious fear and hatred of women in the male, making him sexually apathetic. In both sexes there is a growing alienation between romantic love and sex. PMID:5652746

  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.

  11. The Relationship between Childhood Sexual Abuse and Adult Male Sexual Dysfunction.

    ERIC Educational Resources Information Center

    Sarwer, David B.; And Others

    1997-01-01

    A study of 359 men who sought sexual dysfunction treatment found that childhood sexual abuse did not predict sexual dysfunction in the men. Unemployment was the only significant predictor of male sexual dysfunction. Differences between the sexual abuse experiences of the male victims compared to female victims (n=73) are discussed. (Author/CR)

  12. Amantadine stimulates sexual behavior in male rats.

    PubMed

    Ferraz, M R; Santos, R

    1995-08-01

    The effects of amantadine on sexual behavior, penile erection, and seminal emission of male rats was studied. Amantadine significantly decreased latency of mounts in all doses (1.25 to 50 mg/kg), and decreased the number of mounts and intromission latency at the highest doses used. The lowest dose of amantadine significantly increased ejaculation latency and intromission frequency, while higher doses significantly reduced it, which indicates a biphasic response of the drug. Additionally, seminal emission, erections, and genital grooming were significantly induced by amantadine. Amantadine-induced seminal emissions were impaired by spinal cord transection, which suggests the involvement of supraspinal structures in the drug action. Haloperidol and atropine sulphate significantly reduced seminal emissions and penile erections induced by amantadine. These results demonstrate that amantadine stimulates sexual behavior and genital reflexes in male rats and suggest a facilitatory effect of the drug that probably involves different mechanisms of action.

  13. Fitness improvement of mass-reared sterile males of Ceratitis capitata (Vienna 8 strain) (Diptera: Tephritidae) after gut enrichment with probiotics.

    PubMed

    Hamden, Heithem; Guerfali, Meriem M'Saad; Fadhl, Selma; Saidi, Mouldi; Chevrier, Claude

    2013-04-01

    Successful mass rearing is crucial for sterile insect technique programs. It has been shown that the sterilizing process using gammaradiation results in damage to midgut tissue, cellular organelles, and gut microbiota of flies. This can be responsible for the inferiority of sterile males compared with wild males. A bacteria-enhanced diet could contribute to the improvement of the fly's fitness. We investigated ways of increasing the competitiveness of mass-reared Mediterranean fruit fly, Ceratitis capitata (Wiedemann) sterile males. We tested the hypothesis that the addition of beneficial bacteria to the larvae's diet would lead to a significant increase in their levels in the gut of the sterile adults and consequently improve their size and fitness. As expected, enriching the diet of mass-rearing Vienna-8 strain larvae with beneficial bacteria (Klebsiella pneumonia, Enterobacter spp., and Citrobacter freundii) resulted in increase in the number of Enterobacteriacae communities inhabiting the male's gut and a subsequent significant increase in the size of males and other morphometric traits and enhanced sexual performance of males at emergence.

  14. Transgenic induction of mitochondrial rearrangements for cytoplasmic male sterility in crop plants.

    PubMed

    Sandhu, Ajay Pal S; Abdelnoor, Ricardo V; Mackenzie, Sally A

    2007-02-06

    Stability of the mitochondrial genome is controlled by nuclear loci. In plants, nuclear genes suppress mitochondrial DNA rearrangements during development. One nuclear gene involved in this process is Msh1. Msh1 appears to be involved in the suppression of illegitimate recombination in plant mitochondria. To test the hypothesis that Msh1 disruption leads to the type of mitochondrial DNA rearrangements associated with naturally occurring cytoplasmic male sterility in plants, a transgenic approach for RNAi was used to modulate expression of Msh1 in tobacco and tomato. In both species, these experiments resulted in reproducible mitochondrial DNA rearrangements and a condition of male (pollen) sterility. The male sterility was, in each case, heritable, associated with normal female fertility, and apparently maternal in its inheritance. Segregation of the transgene did not reverse the male sterile phenotype, producing stable, nontransgenic male sterility. The reproducible transgenic induction of mitochondrial rearrangements in plants is unprecedented, providing a means to develop novel cytoplasmic male sterile lines for release as non-GMO or transgenic materials.

  15. Fatal or harmless: extreme bistability induced by sterilizing, sexually transmitted pathogens.

    PubMed

    Berec, Luděk; Maxin, Daniel

    2013-02-01

    Models of sexually transmitted infections have become a fixture of mathematical epidemiology. A common attribute of all these models is treating reproduction and mating, and hence pathogen transmission, as uncoupled events. This is fine for humans, for example, where only a tiny fraction of sexual intercourses ends up with having a baby. But it can be a deficiency for animals in which mating and giving birth are tightly coupled, and mating thus mediates both reproduction and pathogen transmission. Here, we model dynamics of sterilizing, sexually transmitted infections in such animals, assuming structural consistency between the processes of reproduction and pathogen transmission. We show that highly sterilizing, sexually transmitted pathogens trigger bistability in the host population. In particular, the host population can end up in two extreme alternative states, disease-free persistence and pathogen-driven extinction, depending on its initial state. Given that sterilizing, sexually transmitted infections that affect animals are abundant, our results might implicate an effective pest control tactic that consists of releasing the corresponding pathogens, possibly after genetically enhancing their sterilization power.

  16. Review: neuroestrogen regulation of socio-sexual behavior of males

    PubMed Central

    Ubuka, Takayoshi; Tsutsui, Kazuyoshi

    2014-01-01

    It is thought that estrogen (neuroestrogen) synthesized by the action of aromatase in the brain from testosterone activates male socio-sexual behaviors, such as aggression and sexual behavior in birds. We recently found that gonadotropin-inhibitory hormone (GnIH), a hypothalamic neuropeptide, inhibits socio-sexual behaviors of male quail by directly activating aromatase and increasing neuroestrogen synthesis in the preoptic area (POA). The POA is thought to be the most critical site of aromatization and neuroestrogen action for the regulation of socio-sexual behavior of male birds. We concluded that GnIH inhibits socio-sexual behaviors of male quail by increasing neuroestrogen concentration beyond its optimal concentration in the brain for expression of socio-sexual behavior. On the other hand, it has been reported that dopamine and glutamate, which stimulate male socio-sexual behavior in birds and mammals, inhibit the activity of aromatase in the POA. Multiple studies also report that the activity of aromatase or neuroestrogen is negatively correlated with changes in male socio-sexual behavior in fish, birds, and mammals including humans. Here, we review previous studies that investigated the role of neuroestrogen in the regulation of male socio-sexual behavior and reconsider the hypothesis that neuroestrogen activates male socio-sexual behavior in vertebrates. It is considered that basal concentration of neuroestrogen is required for the maintenance of male socio-sexual behavior but higher concentration of neuroestrogen may inhibit male socio-sexual behavior. PMID:25352775

  17. 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 reduc-stertion 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.

  18. 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).

  19. Neighboring genes for DNA-binding proteins rescue male sterility in Drosophila hybrids

    PubMed Central

    Liénard, Marjorie A.; Araripe, Luciana O.; Hartl, Daniel L.

    2016-01-01

    Crosses between closely related animal species often result in male hybrids that are sterile, and the molecular and functional basis of genetic factors for hybrid male sterility is of great interest. Here, we report a molecular and functional analysis of HMS1, a region of 9.2 kb in chromosome 3 of Drosophila mauritiana, which results in virtually complete hybrid male sterility when homozygous in the genetic background of sibling species Drosophila simulans. The HMS1 region contains two strong candidate genes for the genetic incompatibility, agt and Taf1. Both encode unrelated DNA-binding proteins, agt for an alkyl-cysteine-S-alkyltransferase and Taf1 for a subunit of transcription factor TFIID that serves as a multifunctional transcriptional regulator. The contribution of each gene to hybrid male sterility was assessed by means of germ-line transformation, with constructs containing complete agt and Taf1 genomic sequences as well as various chimeric constructs. Both agt and Taf1 contribute about equally to HMS1 hybrid male sterility. Transgenes containing either locus rescue sterility in about one-half of the males, and among fertile males the number of offspring is in the normal range. This finding suggests compensatory proliferation of the rescued, nondysfunctional germ cells. Results with chimeric transgenes imply that the hybrid incompatibilities result from interactions among nucleotide differences residing along both agt and Taf1. Our results challenge a number of preliminary generalizations about the molecular and functional basis of hybrid male sterility, and strongly reinforce the role of DNA-binding proteins as a class of genes contributing to the maintenance of postzygotic reproductive isolation. PMID:27357670

  20. Differences between Sexually Victimized and Nonsexually Victimized Male Adolescent Sexual Abusers: Developmental Antecedents and Behavioral Comparisons

    ERIC Educational Resources Information Center

    Burton, David L.; Duty, Kerry Jo; Leibowitz, George S.

    2011-01-01

    This study compares sexually victimized and nonsexually victimized male adolescent sexual abusers on a number of variables. Self-report measures were administered to 325 male sexually abusive youth (average age 16) in six residential facilities in the Midwest, 55% of whom reported sexual victimization. The results indicate that the sexually…

  1. Sexual functions and quality of life in women with tubal sterilization.

    PubMed

    Gulum, M; Yeni, E; Sahin, M A; Savas, M; Ciftci, H

    2010-01-01

    The aim of this study was to evaluate the sexual functions and quality of life of women who have undergone tubal sterilization after tubal surgery. In all, 90 active premenopausal women, who had undergone tubal sterilization at least 1 year ago and been admitted to four different hospitals, were included in the study group. A total of 100 women at a similar age range, admitted to the same four hospitals for routine health controls, were included in the control group. To obtain sexual function assessments, the patients were asked to fill out Female Sexual Function Index (FSFI) questionnaire. The participants were also asked to fill out Medical Outcomes Study Short Form (SF-36) questionnaire. All values were found to be lower in the tubal sterilization (TS) group and the differences between groups were statistically significant in domain except for pain and lubrication. Similarly, in the analysis of SF-36 scores, there were differences in comparison with the TS group in all domains. In the evaluation of the relationship of FSFI with educational level in the TS group, it was found that, while the educational level increased, all domain scores also increased, and this increase was statistically significant in all domains except pain. The termination of fertility, which is one of the important abilities of women, with tubal sterilization, may be a risk factor for female sexual dysfunction in people with low educational levels.

  2. Two recessive genes controlling thermophotoperiod-sensitive male sterility in wheat.

    PubMed

    Guo, R X; Sun, D F; Tan, Z B; Rong, D F; Li, C D

    2006-05-01

    Male sterility of wheat-breeding line 337S (Triticum aestivum L.) is sensitive to both short day-length/low temperature and long day-length/high temperature. 337S was crossed with the common wheat variety, Huamai No. 8 and the F1 was highly fertile. The F2 population segregated in a 15:1 ratio for fertility/sterility in 243 individuals under long day-length/high-temperature. The two thermophotoperiod-responsive male sterile genes were mapped to chromosomes 5B and 2B using Simple Sequence Repeat (SSR) markers and bulked segregant analysis. Partial linkage maps around the sterility loci of chromosomes 2B and 5B were constructed using the 243 individuals in the F2 population. One gene (wptms1) for male sterility was flanked by the SSR markers Xgwm335 and Xgwm371 at a genetic distance in chromosome 5B of 4.1 and 24.4 cM, respectively. The second gene (wptms2) was mapped between markers Xgwm374 and Xgwm120 at a genetic distance of 6.6 and 20.9 cM, respectively. The closest linked markers Xgwm335 (wptms1) and Xgwm374 (wptms2) explained 53 and 38% of phenotypic variation for the fertility. The SSR markers provide a useful tool to transfer the male sterile genes into elite wheat germplasm.

  3. Genome-wide misexpression of X-linked versus autosomal genes associated with hybrid male sterility.

    PubMed

    Lu, Xuemei; Shapiro, Joshua A; Ting, Chau-Ti; Li, Yan; Li, Chunyan; Xu, Jin; Huang, Huanwei; Cheng, Ya-Jen; Greenberg, Anthony J; Li, Shou-Hsien; Wu, Mao-Lien; Shen, Yang; Wu, Chung-I

    2010-08-01

    Postmating reproductive isolation is often manifested as hybrid male sterility, for which X-linked genes are overrepresented (the so-called large X effect). In contrast, X-linked genes are significantly under-represented among testis-expressing genes. This seeming contradiction may be germane to the X:autosome imbalance hypothesis on hybrid sterility, in which the X-linked effect is mediated mainly through the misexpression of autosomal genes. In this study, we compared gene expression in fertile and sterile males in the hybrids between two Drosophila species. These hybrid males differ only in a small region of the X chromosome containing the Ods-site homeobox (OdsH) (also known as Odysseus) locus of hybrid sterility. Of genes expressed in the testis, autosomal genes were, indeed, more likely to be misexpressed than X-linked genes under the sterilizing action of OdsH. Since this mechanism of X:autosome interaction is only associated with spermatogenesis, a connection between X:autosome imbalance and the high rate of hybrid male sterility seems plausible.

  4. Sterilization.

    PubMed

    Rioux, M H

    1979-05-01

    The history of sterilization in North America has included enactment of laws in 37 U. S. states and 2 Canadian provinces allowing the procedure to be performed to eliminate undesirable, genetically-transmitted traits. These eugenic laws applied to any of the following categories of persons: mentally regarded, mentally ill, epileptic, criminal, alcoholic, or poor people. Pressure from geneticists, lawyers, and others concerned with the implications of such laws, led to their repeal in many places. Noneugenic and nontherapeutic sterilization is today a recognized medical practice. Legally, such procedures must meet the following criteria: 1) informed consent; 2) individual benefit; and 3) performance with reasonable care and skill. If these criteria are met, doctors are protected from legal liability. The most legal, social, and ethical ambiguities arise in cases where nontherapeutic sterilization is performed on individuals unable to give consent, e.g., minors or mentally handicapped persons.

  5. Male Sexual Dysfunction and Chronic Kidney Disease

    PubMed Central

    Edey, Matthew M.

    2017-01-01

    Male sexual dysfunction is common in chronic kidney disease (CKD), particularly in end-stage renal disease. Historically, this cause of considerable morbidity has been under-reported and under-recognized. The ideal approach to diagnosis and management remains unclear due to a paucity of good quality data, but an understanding of the pathophysiology is necessary in order to address the burden of this important complication of CKD. This paper will review the endocrine dysfunction that occurs in renal disease, particularly the hypothalamic–pituitary–gonadal axis, discuss the causes of erectile dysfunction, infertility, and altered body image and libido in these patients and suggest appropriate treatment interventions. PMID:28382300

  6. Heterozygous alleles restore male fertility to cytoplasmic male-sterile radish (Raphanus sativus L.): a case of overdominance.

    PubMed

    Wang, Zhi Wei; De Wang, Chuan; Wang, Chuan; Gao, Lei; Mei, Shi Yong; Zhou, Yuan; Xiang, Chang Ping; Wang, Ting

    2013-04-01

    The practice of hybridization has greatly contributed to the increase in crop productivity. A major component that exploits heterosis in crops is the cytoplasmic male sterility (CMS)/nucleus-controlled fertility restoration (Rf) system. Through positional cloning, it is shown that heterozygous alleles (RsRf3-1/RsRf3-2) encoding pentatricopeptide repeat (PPR) proteins are responsible for restoring fertility to cytoplasmic male-sterile radish (Raphanus sativus L.). Furthermore, it was found that heterozygous alleles (RsRf3-1/RsRf3-2) show higher expression and RNA polymerase II occupancy in the CMS cytoplasmic background compared with their homozygous alleles (RsRf3-1/RsRf3-1 or RsRf3-2/RsRf3-2). These data provide new insights into the molecular mechanism of fertility restoration to cytoplasmic male-sterile plants and illustrate a case of overdominance.

  7. Meiotic sex chromosome inactivation is disrupted in sterile hybrid male house mice.

    PubMed

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

    2013-03-01

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

  8. Molecular-aided selection of male sterility for hybrid development in onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintainer lines are used to seed propagate male-sterile lines for the development of hybrid-onion cultivars. Selection of maintainer lines is more efficient using molecular markers that distinguish cytoplasms and genotypes at the nuclear male-fertility restoration (Ms) locus. Onion cytoplasms can b...

  9. Stranger and acquaintance sexual assault of adult males.

    PubMed

    Stermac, Lana; Del Bove, Giannetta; Addison, Mary

    2004-08-01

    This study examined victim and assault characteristics and the nature and extent of coercion, violence, and physical injuries among adult male victims of sexual assaults. Client records of three groups presenting to a sexual assault care center were included: males assaulted by a stranger (n = 64), males assaulted by an acquaintance (n = 81), and females assaulted by an acquaintance (n = 106). Study results revealed that male victims of sexual assault tended to be young, single men who reported high rates of vulnerabilities such as homelessness and physical, psychiatric, and cognitive disabilities. Male stranger assailant victims were more likely to experience assaults involving weapons and physical violence. Injuries sustained by victims and services delivered at the sexual assault care center were similar for both male and female clients. The results of this study reveal new information about violence in male sexual assaults and the vulnerability of the male victims.

  10. Sexual Agreements among Gay Male Couples

    PubMed Central

    Hoff, Colleen H.; Beougher, Sean C.

    2009-01-01

    Many gay male couples make agreements about whether or not to permit sex with outside partners, yet little is known about the development and maintenance of these agreements, their impact on relationships, and whether they are an effective HIV prevention strategy. Using semi-structured, qualitative interviews, 39 gay male couples were asked about their sexual agreements and about other relationship dynamics that might affect their agreements. Analysis revealed a wide range of agreement types, all of which are presented along a continuum rather than as discrete categories. For couples with open agreements, most placed rules or conditions limiting when, where, how often, and with whom outside sex was permitted. Although motivations for having agreements varied, HIV prevention did not rank as a primary factor for any couple. Most couples had congruous agreements; however, a small number reported discrepancies which may increase HIV transmission risk. How couples handled breaks in their agreements also varied, depending on what condition was broken, whether it was disclosed, and the partner's reaction. Additional results include differences in agreement type and motivations for having an agreement based on couple serostatus. Overall, agreements benefited couples by providing boundaries for the relationship, supporting a non-heteronormative identity, and fulfilling the sexual needs of the couple. Future prevention efforts involving gay couples must address the range of agreement types and the meanings couples ascribe to them, in addition to tempering safety messages with the relationship issues that are important to and faced by gay couples. PMID:18686027

  11. Release of thiotepa sterilized males into caged populations of Aedes aegypti: life table analysis.

    PubMed

    Gato, René; Companioni, Ariamys; Bruzón, Rosa Y; Menéndez, Zulema; González, Aileen; Rodríguez, Misladys

    2014-04-01

    Successful SIT trials against mosquitoes in the 1960-70s were achieved by sterilizing male mosquitoes using chemosterilants. Their use was discontinued after concerns were raised about the effect of residues on non-target organisms, although scant evidence has been published. Irradiation is an expensive process; chemosterilization could be an affordable option for implementing SIT programs in developing countries. We compare life table parameters of three Aedes aegypti populations comprising different ratios of thiotepa-treated and non-treated males in order to identify the impact on reproductive potential of the presence of sterile males. No difference was observed in the survival of the treated and untreated males. The release of thiotepa sterilized males into caged Ae. aegypti populations had no effect on death or survival probability of the individuals in the cages but the fecundity of females was significantly reduced, as evaluated by hatch rate and stable age structure parameters. The significant decreases in net reproduction rate, finite rate of natural increase and intrinsic rate of natural increase in populations including sterile males are sufficient to indicate that such populations would not be able to proliferate in natural conditions. This suggests that release of Ae. aegypti thiotepa-treated males could be effective in reducing the reproductive capability of the target population and consequently contribute to vector control.

  12. Sexual function in women from infertile couples and in women seeking surgical sterilization.

    PubMed

    Hentschel, Heitor; Alberton, Daniele Lima; Sawdy, Robert John; Capp, Edison; Goldim, José Roberto; Passos, Eduardo Pandolfi

    2008-01-01

    The purpose of this study was to compare sexual function between women of infertile couples (AR) and women seeking tubal ligation (TL). Women who attended Setor de Infertilidade do Serviço de Ginecologia e Obstetrícia do Hospital de Clinicas de Porto Alegre (HCPA) or the Serviço de Orientação e Planejamento Familiar (SERPLAN) completed the Female Sexual Function Index, a questionnaire about sexual activity in the last 4 weeks. Scored data were collected on six different domains: desire, arousal, lubrication, orgasm, satisfaction, and discomfort/pain. The greatest positive correlation in the TL group was between orgasm and sexual satisfaction (0.798), and in group AR between desire and arousal (0.627). Infertile women and fertile women who want to undergo surgical sterilization have similar sexual satisfaction scores.

  13. Sexually transmitted infections: impact on male fertility.

    PubMed

    Ochsendorf, F R

    2008-04-01

    The impact of sexually transmitted diseases (STD) on male fertility is strongly dependent on the local prevalence of the STDs. In Western countries STD-infections are of minor relevance. In other regions, i.e. Africa or South East Asia, the situation appears to be different. Acute urethritis could not be associated with male infertility. Chronic infections (gonorrhoea) can cause urethral strictures and epididymo-orchitis. Chlamydia trachomatis and Neisseria gonorrhoea can be transmitted to the female partner and cause pelvic inflammatory disease with tubal obstruction. Ureaplasma urealyticum may impair spermatozoa (motility, DNA condensation). Trichomonas vaginalis has, if any, only minor influence on male fertility. The relevance of viral infections (HPV, HSV) for male infertility is not resolved. Any STD increases the chances of transmission of the human immunodeficiency virus (HIV). The HIV infection is associated with infectious semen and the risk of virus transmission. Semen quality deteriorates with the progression of immunodeficiency. Special counselling of serodiscordant couples is needed. STDs should be treated early and adequately to prevent late sequelae for both men and women.

  14. Male gender identity and sexual behaviour.

    PubMed

    Chused, J F

    1999-12-01

    One consequence of a heightened interest in intersubjectivity in the current psychoanalytic literature has been a relative neglect of the examination of unconscious fantasies. Presenting material from the analysis of three males, each of whom, in childhood and/or adolescence, hid his penis between his legs and looked at himself in a mirror naked, the author demonstrates the importance of attending to both unconscious fantasies and their manifestations within the interactive field of analysis. The first patient is a young child with a gender identity disorder, whose wish to be like his mother was a response to the emotional loss of her during early childhood. The second patient is an adolescent, whose behaviour in front of a mirror was a manifestation of his desire to possess his mother and be her, to humiliate and sadistically control her, and at the same time, to experience the masochistic sexual gratification of being a seemingly helpless victim. The third patient, a 48-year-old male, came to analysis filled with suicidal impulses and self-hatred related to homosexual impulses. His repeated examination of himself in a mirror, with penis hidden, reflected severe castration anxiety, related to an ambivalent relationship with an angry mother and a longing for attention from an unavailable father. The article closes with a description of the similarities and differences in the dynamics of these three males as well as a discussion of the meaning of similar behaviour in other males seen in consultation.

  15. Sterile 'Judas' carp--Surgical sterilisation does not impair growth, endocrine and behavioural responses of male carp.

    PubMed

    Patil, Jawahar G; Purser, G J; Nicholson, A M

    2015-09-15

    Use of 'Judas' fish to betray the locations of conspecifics is a powerful tool in management of invasive pest fish but poses a risk of contributing to recruitment. Our aim therefore was to generate surgically sterilised male common carp (Cyprinus carpio) and test whether they readily assimilate into wild populations, retain sexual behaviour and successfully betray the locations of feral carp. Male common carp were surgically sterilised (n=44) adopting a two-point nip technique, using either a haemoclip, suture or electro cautery to tie each of the testicular ducts about 2.5 cm cranial to urogenital sinus-retaining all of the glandular testis tissue. Observed survival (95%) and success (>70%) rates were relatively high. Plasma steroids (11-keto testosterone and 17β-estradiol) were quantified by immunoassay. A subset of sterile and control male fish (n=7 each) were implanted with radio-transmitters and released into Lake Sorell (50 km(2)) and their ability to betray the location of feral carp was assessed by radio tracking and targeted fishing. There was a statistically significant difference in 11-keto testosterone and 17β-estradiol levels over time (P<0.05), but not between the sterile and control groups within each sampling time (P>0.05), implying that surgery did not compromise the animals physiologically. The sterile Judas fish integrated well into the population-behaving similarly to control Judas males and assisted in the capture of feral carp. The study marks a significant breakthrough in the management of this pest fish with potential adoption to the management of other pest fish globally.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ef...

  17. Genetic Architecture of Male Sterility and Segregation Distortion in Drosophila pseudoobscura Bogota–USA Hybrids

    PubMed Central

    Phadnis, Nitin

    2011-01-01

    Understanding the genetic basis of reproductive isolation between recently diverged species is a central problem in evolutionary genetics. Here, I present analyses of the genetic architecture underlying hybrid male sterility and segregation distortion between the Bogota and USA subspecies of Drosophila pseudoobscura. Previously, a single gene, Overdrive (Ovd), was shown to be necessary but not sufficient for both male sterility and segregation distortion in F1 hybrids between these subspecies, requiring several interacting partner loci for full manifestation of hybrid phenomena. I map these partner loci separately on the Bogota X chromosome and USA autosomes using a combination of different mapping strategies. I find that hybrid sterility involves a single hybrid incompatibility of at least seven interacting partner genes that includes three large-effect loci. Segregation distortion involves three loci on the Bogota X chromosome and one locus on the autosomes. The genetic bases of hybrid sterility and segregation distortion are at least partially—but not completely—overlapping. My results lay the foundation for fine-mapping experiments to identify the complete set of genes that interact with Overdrive. While individual genes that cause hybrid sterility or inviability have been identified in a few cases, my analysis provides a comprehensive look at the genetic architecture of all components of a hybrid incompatibility underlying F1 hybrid sterility. Such an analysis would likely be unfeasible for most species pairs due to their divergence time and emphasizes the importance of young species pairs such as the D. pseudoobscura subspecies studied here. PMID:21900263

  18. Segregation and Heritability of Male Sterility in Populations Derived from Progeny of Satsuma Mandarin

    PubMed Central

    Goto, Shingo; Yoshioka, Terutaka; Ohta, Satoshi; Kita, Masayuki; Hamada, Hiroko

    2016-01-01

    Male sterility derived from Satsuma mandarin (Citrus unshiu) has been used in Japanese citrus breeding programs to obtain seedless cultivars, which is a desirable trait for consumers. Male sterility has often been evaluated by anther development or pollen fertility; however, the inheritance and heritability of male sterility derived from Satsuma is poorly understood. In this study, we investigated the mode of inheritance and broad-sense heritability of male sterility derived from Satsuma. Initially, we evaluated the total number of pollen grains per anther and apparent pollen fertility, as indicated by lactophenol blue staining, in 15 citrus cultivars and selections to understand the male sterility of Satsuma. The results indicated that male sterility was primarily caused by decreased number of pollen grains per anther in progeny of Satsuma. We also evaluated these traits in three F1 populations (hyuganatsu × ‘Okitsu No. 56’, ‘Okitsu No. 46’ × ‘Okitsu No. 56’ and ‘Okitsu No. 46’ × ‘Kara’), of which the parents are derived from Satsuma. Individuals in these populations showed strong segregation for number of pollen grains per anther. The apparent fertility of pollen also showed segregation but was almost constant at 70%–90%. The estimated broad-sense heritability for the number of pollen grains per anther was as high as 0.898 in the ‘Okitsu No. 46’ × ‘Okitsu No. 56’ and ‘Okitsu No. 46’ × ‘Kara’ populations. These results indicated that the number of pollen grains per anther primarily determined male sterility among progeny of Satsuma, and this trait was inherited by the progeny. Development of DNA markers closely linked to male sterility using the F1 populations of ‘Okitsu No. 46’ × ‘Okitsu No. 56’ and ‘Okitsu No. 46’ × ‘Kara’ is expected to contribute to the breeding of novel seedless citrus cultivars. PMID:27589237

  19. Comparison of Irradiation and Wolbachia Based Approaches for Sterile-Male Strategies Targeting Aedes albopictus

    PubMed Central

    Atyame, Célestine M.; Labbé, Pierrick; Lebon, Cyrille; Weill, Mylène; Moretti, Riccardo; Marini, Francesca; Gouagna, Louis Clément; Calvitti, Maurizio; Tortosa, Pablo

    2016-01-01

    The global expansion of Aedes albopictus together with the absence of vaccines for most of the arboviruses transmitted by this mosquito has stimulated the development of sterile-male strategies aiming at controlling disease transmission through the suppression of natural vector populations. In this context, two environmentally friendly control strategies, namely the Sterile Insect Technique (SIT) and the Wolbachia-based Incompatible Insect Technique (IIT) are currently being developed in several laboratories worldwide. So far however, there is a lack of comparative assessment of these strategies under the same controlled conditions. Here, we compared the mating capacities, i.e. insemination capacity, sterilization capacity and mating competitiveness of irradiated (35 Gy) and incompatible Ae. albopictus males at different ages and ratios under laboratory controlled conditions. Our data show that there was no significant difference in insemination capacity of irradiated and incompatible males, both male types showing lower capacities than untreated males at 1 day but recovering full capacity within 5 days following emergence. Regarding mating competitiveness trials, a global observed trend is that incompatible males tend to induce a lower hatching rate than irradiated males in cage controlled confrontations. More specifically, incompatible males were found more competitive than irradiated males in 5:1 ratio regardless of age, while irradiated males were only found more competitive than incompatible males in the 1:1 ratio at 10 days old. Overall, under the tested conditions, IIT seemed to be slightly more effective than SIT. However, considering that a single strategy will likely not be adapted to all environments, our data stimulates the need for comparative assessments of distinct strategies in up-scaled conditions in order to identify the most suitable and safe sterilizing technology to be implemented in a specific environmental setting and to identify the

  20. Comparison of Irradiation and Wolbachia Based Approaches for Sterile-Male Strategies Targeting Aedes albopictus.

    PubMed

    Atyame, Célestine M; Labbé, Pierrick; Lebon, Cyrille; Weill, Mylène; Moretti, Riccardo; Marini, Francesca; Gouagna, Louis Clément; Calvitti, Maurizio; Tortosa, Pablo

    2016-01-01

    The global expansion of Aedes albopictus together with the absence of vaccines for most of the arboviruses transmitted by this mosquito has stimulated the development of sterile-male strategies aiming at controlling disease transmission through the suppression of natural vector populations. In this context, two environmentally friendly control strategies, namely the Sterile Insect Technique (SIT) and the Wolbachia-based Incompatible Insect Technique (IIT) are currently being developed in several laboratories worldwide. So far however, there is a lack of comparative assessment of these strategies under the same controlled conditions. Here, we compared the mating capacities, i.e. insemination capacity, sterilization capacity and mating competitiveness of irradiated (35 Gy) and incompatible Ae. albopictus males at different ages and ratios under laboratory controlled conditions. Our data show that there was no significant difference in insemination capacity of irradiated and incompatible males, both male types showing lower capacities than untreated males at 1 day but recovering full capacity within 5 days following emergence. Regarding mating competitiveness trials, a global observed trend is that incompatible males tend to induce a lower hatching rate than irradiated males in cage controlled confrontations. More specifically, incompatible males were found more competitive than irradiated males in 5:1 ratio regardless of age, while irradiated males were only found more competitive than incompatible males in the 1:1 ratio at 10 days old. Overall, under the tested conditions, IIT seemed to be slightly more effective than SIT. However, considering that a single strategy will likely not be adapted to all environments, our data stimulates the need for comparative assessments of distinct strategies in up-scaled conditions in order to identify the most suitable and safe sterilizing technology to be implemented in a specific environmental setting and to identify the

  1. A genomewide scan of male sexual orientation.

    PubMed

    Mustanski, Brian S; Dupree, Michael G; Nievergelt, Caroline M; Bocklandt, Sven; Schork, Nicholas J; Hamer, Dean H

    2005-03-01

    This is the first report of a full genome scan of sexual orientation in men. A sample of 456 individuals from 146 families with two or more gay brothers was genotyped with 403 microsatellite markers at 10-cM intervals. Given that previously reported evidence of maternal loading of transmission of sexual orientation could indicate epigenetic factors acting on autosomal genes, maximum likelihood estimations (mlod) scores were calculated separated for maternal, paternal, and combined transmission. The highest mlod score was 3.45 at a position near D7S798 in 7q36 with approximately equivalent maternal and paternal contributions. The second highest mlod score of 1.96 was located near D8S505 in 8p12, again with equal maternal and paternal contributions. A maternal origin effect was found near marker D10S217 in 10q26, with a mlod score of 1.81 for maternal meioses and no paternal contribution. We did not find linkage to Xq28 in the full sample, but given the previously reported evidence of linkage in this region, we conducted supplemental analyses to clarify these findings. First, we re-analyzed our previously reported data and found a mlod of 6.47. We then re-analyzed our current data, after limiting the sample to those families previously reported, and found a mlod of 1.99. These Xq28 findings are discussed in detail. The results of this first genome screen for normal variation in the behavioral trait of sexual orientation in males should encourage efforts to replicate these findings in new samples with denser linkage maps in the suggested regions.

  2. Little qualitative RNA misexpression in sterile male F1 hybrids of Drosophila pseudoobscura and D. persimilis

    PubMed Central

    Reiland, Jane; Noor, Mohamed AF

    2002-01-01

    Background Although the genetics of hybrid sterility has been the subject of evolutionary studies for over sixty years, no one has shown the reason(s) why alleles that operate normally within species fail to function in another genetic background. Several lines of evidence suggest that failures in normal gene transcription contribute to hybrid dysfunctions, but genome-wide studies of gene expression in pure-species and hybrids have not been undertaken. Here, we study genome-wide patterns of expression in Drosophila pseudoobscura, D. persimilis, and their sterile F1 hybrid males using differential display. Results Over five thousand amplifications were analyzed, and 3312 were present in amplifications from both of the pure species. Of these, 28 (0.5%) were not present in amplifications from adult F1 hybrid males. Using product-specific primers, we were able to confirm one of nine of the transcripts putatively misexpressed in hybrids. This transcript was shown to be male-specific, but without detectable homology to D. melanogaster sequence. Conclusion We tentatively conclude that hybrid sterility can evolve without widespread, qualitative misexpression of transcripts in species hybrids. We suggest that, if more misexpression exists in sterile hybrids, it is likely to be quantitative, tissue-specific, and/ or limited to earlier developmental stages. Although several caveats apply, this study was a first attempt to determine the mechanistic basis of hybrid sterility, and one potential candidate gene has been identified for further study. PMID:12223116

  3. Morphological Characterization of a New and Easily Recognizable Nuclear Male Sterile Mutant of Sorghum (Sorghum bicolor)

    PubMed Central

    Xin, Zhanguo; Huang, Jian; Smith, Ashley R.; Chen, Junping; Burke, John; Sattler, Scott E.

    2017-01-01

    Sorghum (Sorghum bicolor L. Moench) is one of the most important grain crops in the world. The nuclear male sterility (NMS) trait, which is caused by mutations on the nuclear gene, is valuable for hybrid breeding and genetic studies. Several NMS mutants have been reported previously, but none of them were well characterized. Here, we present our detailed morphological characterization of a new and easily recognizable NMS sorghum mutant male sterile 8 (ms8) isolated from an elite inbred BTx623 mutagenized by ethyl methane sulfonate (EMS). Our results show that the ms8 mutant phenotype was caused by a mutation on a single recessive nuclear gene that is different from all available NMS loci reported in sorghum. In fertile sorghum plants, yellow anthers appeared first during anthesis, while in the ms8 mutant, white hairy stigma emerged first and only small white anthers were observed, making ms8 plants easily recognizable when flowering. The ovary development and seed production after manual pollination are normal in the ms8 mutant, indicating it is female fertile and male sterile only. We found that ms8 anthers did not produce pollen grains. Further analysis revealed that ms8 anthers were defective in tapetum development, which led to the arrest of pollen formation. As a stable male sterile mutant across different environments, greenhouses, and fields in different locations, the ms8 mutant could be a useful breeding tool. Moreover, ms8 might be an important for elucidating male gametophyte development in sorghum and other plants. PMID:28052078

  4. A discourse analysis of male sexuality in the magazine Intimacy

    PubMed Central

    2015-01-01

    Abstract Background The World Health Organization's publication, Developing sexual health programmes, states that the media is an important source of information about sexuality. Although the media can promote awareness of sexual health issues, it also acts as a vehicle for defining and regulating sex norms. In other words, the standards of ‘normal’ sex are in part defined by the media. Accordingly, it has become imperative to analyse the media's construction of sexual norms in order to reveal how they are related to specific ideological views. For the purposes of this study, the focus will be limited to analysing the South African publication Intimacy. Aim The study aims to reveal how the sex advice articles written in Intimacy for women in regard to their male partner's sexuality reflect patriarchal and phallocentric ideologies. Method A discourse analysis of the sex advice articles in the magazine Intimacy was conducted. It was informed by feminist theories of sexuality that seek to examine the ways in which texts are associated with male-centred versions of sexual pleasure. Results The discourse analysis identified a number of key themes regarding male sexuality. These include: (1) biological accounts of male sexuality; (2) phallocentric scripting of the sex act; and (3) the melodramatic penis. Conclusion Constructions of male sexuality require the inclusion of alternative modes of male erotic pleasure. This requires texts that encourage men to explore and also to experiment with pleasurable feelings associated with non-genital erogenous zones of the body. PMID:26245621

  5. Predictors of Sexual Aggression among Male Juvenile Offenders

    ERIC Educational Resources Information Center

    Yeater, Elizabeth A.; Lenberg, Kathryn L.; Bryan, Angela D.

    2012-01-01

    The purpose of this study was to conduct a longitudinal examination of predictors of sexual aggression among male juvenile offenders. Four hundred and four adolescent males between the ages of 14 and 17 years were recruited from juvenile probation offices to take part in a prospective study of substance use and sexual risk. At baseline,…

  6. 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...

  7. Cytoplasmic effects on DNA methylation between male sterile line and its maintainer in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybrid rice is advantageous over the traditional one on food production, which is important to support the increasing world’s population, especially in the developing countries. Three-line system that has played a major role since the 1970s in rice includes male sterile (A line), its maintainer (B l...

  8. Molecular mapping of three nuclear male sterility mutant genes in cultivated sunflower (Helianthus annuus L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The nuclear male sterility (NMS) trait is a useful tool for sunflower (Helianthus annuus L.) breeding and genetic programs. Previously, we induced NMS mutants in cultivated line HA 89. The mutants possessed single recessive genes, ms6, ms7, and ms8, respectively, in NMS HA 89-872, NMS HA 89-552, and...

  9. Partial male sterility and the evolution of nuclear gynodioecy in plants.

    PubMed

    Schultz, Stewart T

    2002-12-01

    Gynodioecy, a genetic dimorphism of females and hermaphrodites, is pertinent to an understanding of the evolution of plant gender, mating and genetic variability. Classical models of nuclear gynodioecy attribute the maintenance of the dimorphism to frequency-dependent selection in which the female phenotype has a fitness advantage at low frequency owing to a doubled ovule fertility. Here, I analyse explicit genetic models of nuclear gynodioecy that expand on previous work by allowing partial male sterility in combination with either fixed or dynamically evolving mutational inbreeding depression. These models demonstrate that partial male sterility causes fitness underdominance at the mating locus, which can prevent the spread of females. However, if partial male sterility is compensated by a change in selfing rate, overdominance at the mating locus can cause the spread of females. Overdominance at introduction of the male sterility allele can be caused by high inbreeding depression and a lower selfing rate in the heterozygote, by purging of mutations by a higher selfing rate in the heterozygote, and by low inbreeding depression and a higher selfing rate in the heterozygote. These processes might be of general importance in the maintenance of mating polymorphisms in plants.

  10. Morphological characterization of a new and easily recognizable nuclear male sterile mutant of sorghum (Sorghum bicolor).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All commercial sorghum (Sorghum bicolor L. Moench) hybrids are produced using A1 cytoplasmic male sterility (CMS) lines. However, this homogenous cytoplasm could predispose sorghum to devastating diseases. Furthermore, it is expensive to develop and maintain the CMS-based breeding system, because it...

  11. Involvement of a universal amino acid synthesis impediment in cytoplasmic male sterility in pepper

    PubMed Central

    Fang, Xianping; Fu, Hong-Fei; Gong, Zhen-Hui; Chai, Wei-Guo

    2016-01-01

    To explore the mechanisms of pepper (Capsicum annuum L.) cytoplasmic male sterility (CMS), we studied the different maturation processes of sterile and fertile pepper anthers. A paraffin section analysis of the sterile anthers indicated an abnormality of the tapetal layer and an over-vacuolization of the cells. The quantitative proteomics results showed that the expression of histidinol dehydrogenase (HDH), dihydroxy-acid dehydratase (DAD), aspartate aminotransferase (ATAAT), cysteine synthase (CS), delta-1-pyrroline-5-carboxylate synthase (P5CS), and glutamate synthetase (GS) in the amino acid synthesis pathway decreased by more than 1.5-fold. Furthermore, the mRNA and protein expression levels of DAD, ATAAT, CS and P5CS showed a 2- to 16-fold increase in the maintainer line anthers. We also found that most of the amino acid content levels decreased to varying degrees during the anther tapetum period of the sterile line, whereas these levels increased in the maintainer line. The results of our study indicate that during pepper anther development, changes in amino acid synthesis are significant and accompany abnormal tapetum maturity, which is most likely an important cause of male sterility in pepper. PMID:26987793

  12. Chronic amantadine treatment enhances the sexual behaviour of male rats.

    PubMed

    Ferraz, Marcia Martins Dias; Fontanella, Julia Cordeiro; Damasceno, Fabio; Silva de Almeida, Olga Maria Martins; Ferraz, Marcos Rochedo

    2007-04-01

    The acute administration of amantadine (AMA), a dopaminomimetic and NMDA glutamatergic receptor antagonist also used as an anti-Parkinsonian agent, stimulates male rat sexual behaviour. However it remains unclear whether long term AMA supplementation might also provoke a similar increase in male rat sexual conduct. In the present study, male rats were administered AMA (5-50 mg/kg/day) or vehicle daily for 21 days and their sexual response was monitored weekly. Chronic treatment with AMA effectively increased the sexual response of male rats, similarly to what had been observed before with acute amantadine treatment. The main effect of chronic AMA treatment occurs in arousal and in ejaculatory response, whilst the excitatory component was not affected. The 21-day treatment with AMA did not lead to tolerance, suggesting that perhaps AMA could be used in male human patients to prevent sexual inhibition caused by anti-depressant and anti-psychotic agents.

  13. Sexual selection of male parental care in giant water bugs.

    PubMed

    Ohba, Shin-Ya; Okuda, Noboru; Kudo, Shin-Ichi

    2016-05-01

    Paternal care can be maintained under sexual selection, if it helps in attracting more mates. We tested the hypothesis in two giant water bug species, Appasus major and Appasus japonicus, that male parental care is sexually selected through female preference for caring males. Females were given an opportunity to choose between two males. In the first test of female mate choice, one male carried eggs on its back, while the other did not. The egg status was switched between these two males in the second test. The experiment revealed that females of both species preferred caring males (i.e. egg-bearing) to non-caring males. Nonetheless, the female mate preference for egg-bearing males was stronger in A. major than in A. japonicus. Our results suggest that sexual selection plays an important role in maintaining elaborate paternal care in giant water bugs, but the importance of egg-bearing by males in female mate choice varies among species.

  14. Effects of x-ray irradiation on male navel orangeworm (Lepidoptera: Pyralidae) on mating, fecundity, fertility, and inherited sterility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Male adult navel orangeworm, Amyelois transitella, were irradiated using a laboratory x-ray emitter to determine the dose needed to achieve complete egg sterility of mated female moths and inherited egg sterility of F1 generation. Adult male A. transitella were irradiated in a series of two experime...

  15. 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

    2015-06-15

    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 in most 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.

  16. Targeted sequence capture provides insight into genome structure and genetics of male sterility in a gynodioecious diploid strawberry, Fragaria vesca ssp. bracteata (Rosaceae).

    PubMed

    Tennessen, Jacob A; Govindarajulu, Rajanikanth; Liston, Aaron; Ashman, Tia-Lynn

    2013-08-07

    Gynodioecy is a sexual system wherein females coexist with hermaphrodites. It is of interest not only because male-sterile plants are advantageous in plant breeding but also because it can be a crucial step in the evolutionary transition to entirely separate sexes (dioecy) from a hermaphroditic ancestor. The gynodioecious diploid wild strawberry, Fragaria vesca ssp. bracteata (Rosaceae), is a member of a clade with both dioecious and cultivated species, making it an ideal model in which to study the genetics of male sterility. To create a genetic map of F. v. ssp. bracteata, we identified informative polymorphisms from genomic sequencing (3-5x coverage) of two outbred plants from the same population. Using targeted enrichment, we sequenced 200 bp surrounding each of 6575 polymorphisms in 48 F1 offspring, yielding genotypes at 98% of targeted sites with mean coverage >100x, plus more than 600-kb high-coverage nontargeted sequence. With the resulting linkage map of 7802 stringently filtered markers (5417 targeted), we assessed recombination rates and genomic incongruities. Consistent with past work in strawberries, male sterility is dominant, segregates 1:1, and maps to a single location in the female. Further mapping an additional 55 offspring places male sterility in a gene-dense, 338-kb region of chromosome 4. The region is not syntenic with the sex-determining regions in the closely related octoploids, F. chiloensis and F. virginiana, suggesting either independent origins or translocation. The 57 genes in this region do not include protein families known to control male sterility and thus suggest alternate mechanisms for the suppression of male function.

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

    PubMed Central

    Reed, Laura K.; LaFlamme, Brooke A.; Markow, Therese A.

    2008-01-01

    Background The 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 Findings Isofemale strains of D. mojavensis vary significantly in their production of sterile F1 sons when females are crossed to D. arizonae males. We took advantage of the intraspecific polymorphism, in a novel 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) in the F1 is complex, involving multiple QTL, epistasis, and cytoplasmic effects. Conclusions/Significance The role of extensive intraspecific polymorphism, multiple QTL, and epistatic interactions in HMS in this young species pair shows that HMS is arising as a complex trait in this system. Directional selection alone would be unlikely to maintain polymorphism at multiple loci, thus we hypothesize that directional selection is unlikely to be the only evolutionary force influencing postzygotic isolation. PMID:18728782

  18. Single-layer tungsten oxide as intelligent photo-responsive nanoagents for permanent male sterilization.

    PubMed

    Liu, Zhen; Liu, Xianjun; Ran, Xiang; Ju, Enguo; Ren, Jinsong; Qu, Xiaogang

    2015-11-01

    Permanent male sterilization has been recognized as useful tools for the development of neuter experimental animals and fattening livestock, as well as efficient control of pet overpopulation. Traditional routes such as surgical ways, chemical injections, and anti-fertility vaccines have addressed these crucial problems with idea outcomes. However, these routes usually bring out serious pain and infection towards animals, as well as induce long-term adverse reaction and immune suppression. Thus, a convenient, but non-surgical strategy for male sterilization under a mild manner is highly desirable. Here, for the first time, we demonstrate a novel platform for male sterilization by using single-layer WO2.72 nanosheets as smart photo-responsive sterilants. Upon a 980 nm irradiation, these nanoagents can possess intrinsic NIR-induced hyperthermia and sensitize the formation of singlet oxygen due to the cooperation of photothermal and photodynamic effects. Mechanism of cellular injury can be attributed to the denaturation of protein and apoptosis-related death. Moreover, long-term toxicity and possible metabolism route after testicular injection are discussed, indicating the neglectable systemic toxicity and high bio-compatibility of our nanoagents. Overall, our strategy can extremely overcome the shortcomings in various routine routes and suggest the new biological application of nanomaterials.

  19. Sexual coercion experience and sexually coercive behavior: a population study of Swedish and Norwegian male youth.

    PubMed

    Seto, Michael C; Kjellgren, Cecilia; Priebe, Gisela; Mossige, Svein; Svedin, Carl Göran; Långström, Niklas

    2010-08-01

    The authors tested the hypothesis that experiencing sexual coercion and engaging in sexually coercive behavior are positively associated in a representative sample totaling almost 4,000 Swedish or Norwegian male high school students (estimated response rate 80%). In both surveys, youths who had experienced sexual coercion were approximately three times more likely to engage in sexually coercive behavior than those without such experience (10%-12% vs. 4%). The association between sexual coercion experience and sexually coercive behavior was attenuated but remained significant and moderately strong in both surveys when controlling for nonsexual antisocial behavior, substance use, and noncoercive sexual behavior in multivariate logistic regression models. The population attributable fraction (proportion of sexually coercive behavior that can be explained by sexual coercion experience) was 18%-25%. The findings support a robust link between having been sexually coerced and engaging in coercive sexual behavior in the general population.

  20. Predictors of sexual aggression among male juvenile offenders.

    PubMed

    Yeater, Elizabeth A; Lenberg, Kathryn L; Bryan, Angela D

    2012-05-01

    The purpose of this study was to conduct a longitudinal examination of predictors of sexual aggression among male juvenile offenders. Four hundred and four adolescent males between the ages of 14 and 17 years were recruited from juvenile probation offices to take part in a prospective study of substance use and sexual risk. At baseline, participants completed a series of questionnaires that assessed putative risk factors for sexual aggression. They then completed a measure of sexual aggression at the 6-month follow-up period. Correlational analyses revealed that participants who reported hard drug use, more frequent alcohol and marijuana use, and less severe offenses reported engaging in more severe sexual aggression. In addition, participants who reported higher impulsivity, sensation seeking, and externalizing behaviors also reported participating in more severe sexual aggression. When these variables were included in a regression analysis, only externalizing behaviors and severity of offense uniquely predicted severity of sexual aggression at the 6-month follow-up.

  1. Sodium nitroprusside impairs sexual competence of male rats.

    PubMed

    Ratnasooriya, W D; Jayakody, J R A C; Dharmasiri, M G

    2004-04-01

    Recently, sodium nitroprusside (SNP), a potent nitric oxide (NO) donor and a clinically used antihypertensive, has been introduced as a penile self-injection medical therapy for erectile dysfunction. However, it is known that many antihypertensives impairs sexual competence; NO regulates sexual competence and NO is cytostatic and cytotoxic for human sperm. Thus, a possibility exists that SNP may impair male reproductive competence. Testing this aspect is the aim of this study. This was assessed in male rats (using three i.p. doses: 60, 30 or 20 microg/kg) using noncompetitive copulation tests. The results show that the highest dose of SNP was toxic and caused rapid mortality of treated rats (within 30 min). The mid and low doses of SNP reversibly impaired several parameters of sexual competence in a dose-related fashion: sexual arousability, libido and sexual vigour. Some parameters of sexual behaviour remained unaltered: sexual motivation and intromission ratio, whilst one parameter was improved: sexual performance. In complete contrast, the ejaculatory competence and fertility remained unchanged. The SNP-induced impairments in sexual competence may be attributable to lowered testosterone levels and sedation mediated via its specific action and/or side effect. Further, this impairment of sexual function was not due to general toxicity, inhibition of penile sensitivity, penile erection or analgesic activity. It is concluded that SNP impairs male sexual competence, at least, in rats although it promotes penile erection.

  2. Sexual and natural selection both influence male genital evolution.

    PubMed

    House, Clarissa M; Lewis, Zenobia; Hodgson, Dave J; Wedell, Nina; Sharma, Manmohan D; Hunt, John; Hosken, David J

    2013-01-01

    Rapid and divergent evolution of male genital morphology is a conspicuous and general pattern across internally fertilizing animals. Rapid genital evolution is thought to be the result of sexual selection, and the role of natural selection in genital evolution remains controversial. However, natural and sexual selection are believed to act antagonistically on male genital form. We conducted an experimental evolution study to investigate the combined effects of natural and sexual selection on the genital-arch lobes of male Drosophila simulans. Replicate populations were forced to evolve under lifetime monogamy (relaxed sexual selection) or lifetime polyandry (elevated sexual selection) and two temperature regimes, 25°C (relaxed natural selection) or 27°C (elevated natural selection) in a fully factorial design. We found that natural and sexual selection plus their interaction caused genital evolution. Natural selection caused some aspects of genital form to evolve away from their sexually selected shape, whereas natural and sexual selection operated in the same direction for other shape components. Additionally, sexual and natural selection tended to favour larger genitals. Thus we find that the underlying selection driving genital evolution is complex, does not only involve sexual selection, and that natural selection and sexual selection do not always act antagonistically.

  3. Sexual and Natural Selection Both Influence Male Genital Evolution

    PubMed Central

    Hodgson, Dave J.; Wedell, Nina; Sharma, Manmohan D.; Hunt, John; Hosken, David J.

    2013-01-01

    Rapid and divergent evolution of male genital morphology is a conspicuous and general pattern across internally fertilizing animals. Rapid genital evolution is thought to be the result of sexual selection, and the role of natural selection in genital evolution remains controversial. However, natural and sexual selection are believed to act antagonistically on male genital form. We conducted an experimental evolution study to investigate the combined effects of natural and sexual selection on the genital-arch lobes of male Drosophila simulans. Replicate populations were forced to evolve under lifetime monogamy (relaxed sexual selection) or lifetime polyandry (elevated sexual selection) and two temperature regimes, 25°C (relaxed natural selection) or 27°C (elevated natural selection) in a fully factorial design. We found that natural and sexual selection plus their interaction caused genital evolution. Natural selection caused some aspects of genital form to evolve away from their sexually selected shape, whereas natural and sexual selection operated in the same direction for other shape components. Additionally, sexual and natural selection tended to favour larger genitals. Thus we find that the underlying selection driving genital evolution is complex, does not only involve sexual selection, and that natural selection and sexual selection do not always act antagonistically. PMID:23717488

  4. Hybridization using cytoplasmic male sterility, cytoplasmic herbicide tolerance, and herbicide tolerance from nuclear genes

    SciTech Connect

    Beversdorf, W.D.; Erickson, L.R.; Grant, I.

    1987-04-14

    An improved process is described for producing a substantially homogeneous population of plants of a predetermined hybrid variety of crop which is capable of undergoing self-pollination and cross-pollination. The process comprises: growing in a first planting area a substantially random population of cytoplasmic male sterile plants which exhibit cytoplasmic herbicide tolerance to at least one Type A herbicide and exhibit tolerance to at least one Type B herbicide which is attributable solely to homozygous dominant nuclear genes and male fertile plants which are homozygous recessive maintainer plants for the cytoplasmic male sterile plants and which lack the cytoplasmic herbicide tolerance to at least one Type A herbicide and exhibit tolerance to at least one Type B herbicide attributable solely to the homozygous dominant nuclear genes.

  5. Antisense inhibition of mitochondrial pyruvate dehydrogenase E1alpha subunit in anther tapetum causes male sterility.

    PubMed

    Yui, Rika; Iketani, Satoru; Mikami, Tetsuo; Kubo, Tomohiko

    2003-04-01

    We hypothesized that cytoplasmic male sterility (CMS) in sugar beet may be the consequence of mitochondrial dysfunctions affecting normal anther development. To test the hypothesis, we attempted to mimic the sugar beet CMS phenotype by inhibiting the expression of mitochondrial pyruvate dehydrogenase (PDH), which is essential for the operation of the tricarboxylic acid (TCA) cycle. Screening with a cDNA library of sugar beet flower buds allowed the identification of two PDH E1alpha subunit genes (bvPDH_E1alpha-1 and bvPDH_E1alpha-2). bvPDH_E1alpha-1 was found to be highly expressed in tap roots, whereas bvPDH_E1alpha-2 was expressed most abundantly in flower buds. Green fluorescent protein (GFP) fusion of bvPDH_E1alpha revealed mitochondrial targeting properties. A 300-bp bvPDH_E1alpha-1 cDNA sequence (from +620 to +926) was connected to a tapetum-specific promoter in the antisense orientation and then introduced into tobacco. Antisense expression of bvPDH_E1alpha-1 resulted in conspicuously decreased endogenous bvPDH_E1alpha-1 transcripts and male sterility. The tapetum in the male-sterile anthers showed swelling or abnormal vacuolation. It is also worth noting that in the sterile anthers, cell organelles, such as elaioplasts, tapetosomes and orbicules were poorly formed and microspores exhibited aberrant exine development. These features are shared by sugar beet CMS. The results thus clearly indicate that inhibition of PDH activity in anther tapetum is sufficient to cause male sterility, a phenocopy of the sugar beet CMS.

  6. 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.

  7. 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

  8. 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.

  9. A historical perspective on the male sexual case history.

    PubMed

    Quallich, Susanne A

    2014-01-01

    The contemporary sexual medicine case history is grounded in the Biopsychosocial Model and its recognition that the past influences one's current interpretation of symptoms. However, the thread of this model can be found throughout the case studies of the early pioneers of sexology. These early investigators began with examinations of homosexual men, slowly moving toward awareness that male sexuality comprises a continuum, while striving to place sexual behavior in a biologic context. Their perspectives served to establish the groundwork for the emerging construct of sexuality and helped shape current methods for identification of sexual function concerns.

  10. Whole Mitochondrial Genome Sequencing and Re-Examination of a Cytoplasmic Male Sterility-Associated Gene in Boro-Taichung-Type Cytoplasmic Male Sterile Rice

    PubMed Central

    Kazama, Tomohiko; Toriyama, Kinya

    2016-01-01

    Nuclear genome substitutions between subspecies can lead to cytoplasmic male sterility (CMS) through incompatibility between nuclear and mitochondrial genomes. Boro-Taichung (BT)-type CMS rice was obtained by substituting the nuclear genome of Oryza sativa subsp. indica cultivar Chinsurah Boro II with that of Oryza sativa subsp. japonica cultivar Taichung 65. In BT-type CMS rice, the mitochondrial gene orf79 is associated with male sterility. A complete sequence of the Boro-type mitochondrial genome responsible for BT-type CMS has not been determined to date. Here, we used pyrosequencing to construct the Boro-type mitochondrial genome. The contiguous sequences were assembled into five circular DNA molecules, four of which could be connected into a single circle. The two resulting subgenomic circles were unable to form a reliable master circle, as recombination between them was scarcely detected. We also found an unequal abundance of DNA molecules for the two loci of atp6. These results indicate the presence of multi-partite DNA molecules in the Boro-type mitochondrial genome. Expression patterns were investigated for Boro-type mitochondria-specific orfs, which were not found in the mitochondria from the standard japonica cultivar Nipponbare. Restorer of fertility 1 (RF1)-dependent RNA processing has been observed in orf79-containing RNA but was not detected in other Boro-type mitochondria-specific orfs, supporting the conclusion that orf79 is a unique CMS-associated gene in Boro-type mitochondria. PMID:27414645

  11. Doramectin reduces sexual behavior and penile erection in male rats.

    PubMed

    Ferri, R; Todon E Silva, A F S; Cabral, D; Moreira, N; Spinosa, H S; Bernardi, M M

    2013-01-01

    Doramectin (DOR) is an antiparasitic drug that is widely used in domestic animals. In mammals, DOR acts as a γ-aminobutyric acid receptor agonist. This neurotransmitter plays an important role in the regulation of sexual behavior. The present study investigated the effects of two medically relevant doses of DOR on sexual behavior in male rats. We also examined whether previous sexual experience modulates responses to DOR. General activity was first observed in an open field 24, 48, and 72 h after administration of 0.1 and 0.3 mg/kg DOR to determine the dose and time effects of the drug. Apomorphine-induced penile erection and sexual behavior in inexperienced male rats were then analyzed. The effects of previous sexual experience on subsequent sexual behavior in DOR-treated rats (0.3 mg/kg, 24 h prior to the test) were also assessed. The standard therapeutic dose (0.2 mg/kg) did not modify general activity or penile erection. A slightly concentrated dose of 0.3 mg/kg, which is still within the therapeutic range, decreased apomorphine-induced penile erection, whereas 0.2 mg/kg did not modify this behavior. Compared with controls, sexual behavior in inexperienced male rats was impaired after 0.3 mg/kg DOR. Previous sexual experience had little impact on the effects of 0.3 mg/kg DOR. In conclusion, the 0.2 mg/kg dose of DOR did not affect motor behavior or apomorphine-induced penile erection. At a more slightly higher dose level, the appetitive and consummatory phases of sexual behavior in inexperienced male rats were impaired. Previous sexual experience was unable to reverse this sexual impairment, suggesting that previous sexual experience does not exert a positive effect in attenuating sexual impairment produced by DOR treatment.

  12. Creating Completely Both Male and Female Sterile Plants by Specifically Ablating Microspore and Megaspore Mother Cells

    PubMed Central

    Huang, Jian; Smith, Ashley R.; Zhang, Tianyu; Zhao, Dazhong

    2016-01-01

    Although genetically modified (GM) plants have improved commercially important traits, such as biomass and biofuel production, digestibility, bioremediation, ornamental value, and tolerance to biotic and abiotic stresses, there remain economic, political, or social concerns over potential ecological effects of transgene flow from GM plants. The current solution for preventing transgene flow from GM plants is genetically engineering sterility; however, approaches to generating both male and female sterility are limited. In addition, existing strategies for creating sterility lead to loss or modifications of entire flowers or floral organs. Here, we demonstrate that instead of the 1.5-kb promoter, the entire SOLO DANCERS (SDS) gene is required for its meiocyte-specific expression. We then developed an efficient method to specifically ablate microspore and megaspore mother cells using the SDS and BARNASE fusion gene, which resulted in complete sterility in both male and female reproductive organs in Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum), but did not affect plant growth or development, including the formation of all flower organs. Therefore, our research provides a general and effective tool to prevent transgene flow in GM plants. PMID:26870055

  13. Male vulnerability explains the occurrence of sexual cannibalism in a moderately sexually dimorphic wolf spider.

    PubMed

    Fernández-Montraveta, Carmen; González, José Miguel; Cuadrado, Mariano

    2014-06-01

    Sexual cannibalism is a widespread phenomenon among a few animal taxa. Its occurrence is interpreted as female and/or male optimal reproductive decisions or as a non-adaptive side effect of selection for efficiently foraging females. In spite of the amount of research addressed at understanding its evolutionary origins, we lack accurate information about the proximate causes of sexual cannibalism. In a moderately sexually dimorphic wolf spider (Hogna radiata, Araneae, Lycosidae) we assessed the factors mediating the occurrence of sexual cannibalism and its fitness benefits to females. Sexual cannibalism was a rather common outcome of laboratory mating interactions, occurring in more than a quarter percent of courtship interactions involving virgin females. Sexual cannibalism mostly followed mating. Occurrence of sexual cannibalism depended on male vulnerability to female attacks: relatively smaller males were at higher risk of being attacked and older males were less likely to avoid female attacks. Sexual cannibalism had direct and positive effects on female fitness, as sexually cannibalistic females exhibited increased fecundity irrespective of their size, condition and foraging rate. Male consumption was almost complete and represented a relevant food intake to females. We interpret sexual cannibalism as a strategic foraging decision for H. radiata females that adjust their aggressive behaviour towards males so as to limit its potential costs.

  14. A male sterility-associated mitochondrial protein in wild beets causes pollen disruption in transgenic plants.

    PubMed

    Yamamoto, Masayuki P; Shinada, Hiroshi; Onodera, Yasuyuki; Komaki, Chihiro; Mikami, Tetsuo; Kubo, Tomohiko

    2008-06-01

    In higher plants, male reproductive (pollen) development is known to be disrupted in a class of mitochondrial mutants termed cytoplasmic male sterility (CMS) mutants. Despite the increase in knowledge regarding CMS-encoding genes and their expression, definitive evidence that CMS-associated proteins actually cause pollen disruption is not yet available in most cases. Here we compare the translation products of mitochondria between the normal fertile cytoplasm and the male-sterile I-12CMS(3) cytoplasm derived from wild beets. The results show a unique 12 kDa polypeptide that is present in the I-12CMS(3) mitochondria but is not detectable among the translation products of normal mitochondria. We also found that a mitochondrial open reading frame (named orf129) was uniquely transcribed in I-12CMS(3) and is large enough to encode the novel 12 kDa polypeptide. Antibodies against a GST-ORF129 fusion protein were raised to establish that this 12 kDa polypeptide is the product of orf129. ORF129 was shown to accumulate in flower mitochondria as well as in root and leaf mitochondria. As for the CMS-associated protein (PCF protein) in petunia, ORF129 is primarily present in the matrix and is loosely associated with the inner mitochondrial membrane. The orf129 sequence was fused to a mitochondrial targeting pre-sequence, placed under the control of the Arabidopsis apetala3 promoter, and introduced into the tobacco nuclear genome. Transgenic expression of ORF129 resulted in male sterility, which provides clear supporting evidence that ORF129 is responsible for the male-sterile phenotype in sugar beet with wild beet cytoplasm.

  15. Discovery of a novel cytoplasmic male-sterility and its restorer lines in radish (Raphanus sativus L.).

    PubMed

    Lee, Young-Pyo; Park, Suhyung; Lim, Chaewan; Kim, Hyojung; Lim, Heerae; Ahn, Youngsoon; Sung, Soon-Kee; Yoon, Moo-Kyoung; Kim, Sunggil

    2008-10-01

    A male-sterile (MS) radish (Raphanus sativus L.) was found in an accession collected from Uzbekistan. Unlike Ogura MS radishes in which no pollen grain is typically visible during anthesis, a small number of pollen grains stuck together in the dehiscing anthers was observed in the newly identified MS radish. Fluorescein diacetate tests and scanning electron micrographs showed that pollen grains in the new MS radish were severely deformed and non-viable. Cytological examination of pollen development stages showed a clear difference in the defective stage from that seen in Ogura male-sterility. Reciprocal cross-pollination with diverse male-fertile lines indicated that pollen grains of the new MS radish were completely sterile, and the female organs were fully fertile. When the new MS radish and Ogura MS lines were cross-pollinated with a set of eight breeding lines, all F1 progeny originating from crosses with the new MS radish were male-sterile. In contrast, most of the F1 progeny resulting from crosses with Ogura MS lines were male-fertile. These results demonstrated that factors associated with induction of the newly identified male-sterility are different from those of Ogura male-sterility. The lack of restorer lines for the newly identified male-sterility led us to predict that it might be a complete cytoplasmic male-sterility without restorer-of-fertility genes in nuclear genomes. However, cross-pollination with more diverse radish germplasm identified one accession introduced from Russia that could completely restore fertility, proving the existence of restorer-of-fertility gene(s) for the new male-sterility. Meanwhile, the PCR amplification profile of molecular markers for the classification of radish mitochondrial genome types revealed that the new MS radish contained a novel mitotype.

  16. Sexual competitiveness and compatibility between mass-reared sterile flies and wild populations of Anastrepha Ludens (Diptera: Tephritidae) from different regions in Mexico

    SciTech Connect

    Orozco-Davila, D.; Hernandez, R.; Meza, S.; Dominguez, J.

    2007-03-15

    The mass-reared colony of Anastrepha ludens (Loew) currently used in Mexico for suppression of the Mexican fruit fly has been in use for over 10 years. Sterile flies are released into a wide range of environmental conditions as part of an integrated area-wide approach to suppress diverse populations of this pest in the Mexican Republic. This paper assesses the performance of the sterile flies interacting with wild populations from the different environments. We investigated the sexual compatibility and competitiveness of the sterile flies when competing with wild populations from 6 representatives Mexican states: Nuevo Leon, Tamaulipas, Sinaloa, Nayarit, Michoacan, and Chiapas. Results show that the males of the wild populations differed in the time to the onset and peak of sexual activity. Nevertheless, the index of sexual isolation (ISI) reflected sexual compatibility between the populations and the mass-reared strain, indicating that the sterile individuals mate satisfactorily with the wild populations from the 6 states. The male relative performance index (MRPI) showed that the sterile male is as effective in copulating as the wild males. The female relative performance index (FRPI) reflected a general tendency for wild females to copulate in greater proportion than the sterile females, except for the strains from Tamaulipas and Chiapas. In general, the lower participation of the sterile females in copulation increases the possibilities of sterile males to mate with wild females. The relative sterility index (RSI) showed that the acceptance by wild females of the sterile males (25-55%) was similar to that of wild males. Females of the Chiapas strain showed the lowest acceptance of sterile males. Finally, the results obtained in the Fried test (which measures induced sterility in eggs) showed a competitiveness coefficient ranging from 0.2 to 0.5. This suggests that sterile males successfully compete and are compatible with flies from different geographic origins

  17. The Propensity of Pentatricopeptide Repeat Genes to Evolve into Restorers of Cytoplasmic Male Sterility

    PubMed Central

    Gaborieau, Lydiane; Brown, Gregory G.; Mireau, Hakim

    2016-01-01

    Cytoplasmic male sterility (CMS) is a widespread phenotype in plants, which present a defect in the production of functional pollen. The male sterilizing factors usually consist of unusual genes or open reading frames encoded by the mitochondrial genome. CMS can be suppressed by specific nuclear genes called restorers of fertility (Rfs). In the majority of cases, Rf genes produce proteins that act directly on the CMS conferring mitochondrial transcripts by binding them specifically and promoting processing events. In this review, we explore the wide array of mechanisms guiding fertility restoration. PPR proteins represent the most frequent protein class among identified Rfs and they exhibit ideal characteristics to evolve into restorer of fertility when the mechanism of restoration implies a post-transcriptional action. Here, we review the literature that highlights those characteristics and help explain why PPR proteins are ideal for the roles they play as restorers of fertility. PMID:27999582

  18. Genetic analysis of abnormal male sexual development in Aedes aegypti and Ae. mascarensis backcross progeny.

    PubMed

    Hilburn, L R; Rai, K S

    1982-01-01

    When male hybrids of Aedes aegypti females and A. mascarensis males were backcrossed to A. aegypti females, 32.8 percent of the male progeny exhibited abnormal sexual development, including failure of the terminalia to rotate, a split sternite of the eighth abdominal segment with partially duplicated telomeres, or feminization that gives rise to sterile intersexes. Observations made on three morphological marker loci and five isozyme loci with characteristic electromorphs in the two parental species suggested that when the sex-determining M locus is derived from A. mascarensis and the chromosome regions including s, LDH, and lDH2 on chromosome 2 and blt and 6PGD on chromosome 3 are homozygous for genes from A. aegypti, the frequency of abnormal sexual development is increased. An even greater percentage of males suffer aberrant development if recombination also occurs between the M and re locus of chromosome 1. The data suggest that genes on chromosome 2 control normal development of the male terminalia, genes on chromosome 3 control sexual differentiation, and the entire process is controlled by genes on chromosome 1 that are linked to, but not identical with, the M locus.

  19. 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…

  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. 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

  2. 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.

  3. Transient population dynamics of mosquitoes during sterile male releases: modelling mating behaviour and perturbations of life history parameters.

    PubMed

    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

  4. 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.

  5. Radiation-induced metabolomic changes in sterile male Μοnochamus alternatus (Coleoptera: Cerambycidae).

    PubMed

    Qu, L J; Wang, L J; Zhang, Y A; Wang, Q H; Wang, Y Z; Zhao, T H; Cai, W Z

    2014-01-01

    Radiation-induced sterile insect technique is a biologically based, environment-friendly method for the suppression or eradication of a number of insect pests. Although the basic mechanisms underlying the technology have been well studied, little is known about the cell responses in organisms. Characterization of the metabolic shift associated with radiation exposure in sterile insects would be helpful for understanding the detailed mechanism underlying this technique and promote its practical application. In this article, a metabolomic study was performed to characterize the global metabolic changes induced by radiation using untreated and 40 Gy (60)Coγ-irradiated testes of Japanese pine sawyer, Monochamus alternatus Hope. Differential metabolites were detected and tentatively identified. Many key metabolites in glycolysis and the tricarboxylic acid cycle, as well as most fatty and amino acids, were elevated in irradiated male M. alternatus, presumably resulting from depression of glycolysis and the tricarboxylic acid cycle, each of which are important pathways for energy generation Adenosine Triphosphate (ATP) in insect spermatozoa. The findings in this article will contribute to our knowledge of the characteristic metabolic changes associated with irradiation sterility and understand the molecular mechanisms underlying radiation-induced sterile insect technique.

  6. Sneaker Males Affect Fighter Male Body Size and Sexual Size Dimorphism in Salmon.

    PubMed

    Weir, Laura K; Kindsvater, Holly K; Young, Kyle A; Reynolds, John D

    2016-08-01

    Large male body size is typically favored by directional sexual selection through competition for mates. However, alternative male life-history phenotypes, such as "sneakers," should decrease the strength of sexual selection acting on body size of large "fighter" males. We tested this prediction with salmon species; in southern populations, where sneakers are common, fighter males should be smaller than in northern populations, where sneakers are rare, leading to geographical clines in sexual size dimorphism (SSD). Consistent with our prediction, fighter male body size and SSD (fighter male∶female size) increase with latitude in species with sneaker males (Atlantic salmon Salmo salar and masu salmon Oncorhynchus masou) but not in species without sneakers (chum salmon Oncorhynchus keta and pink salmon Oncorhynchus gorbuscha). This is the first evidence that sneaker males affect SSD across populations and species, and it suggests that alternative male mating strategies may shape the evolution of body size.

  7. 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.

  8. Social preferences based on sexual attractiveness: a female strategy to reduce male sexual attention.

    PubMed

    Brask, Josefine B; Croft, Darren P; Thompson, Katharine; Dabelsteen, Torben; Darden, Safi K

    2012-05-07

    Male sexual harassment of females is common across sexually reproducing species and can result in fitness costs to females. We hypothesized that females can reduce unwanted male attention by constructing a social niche where their female associates are more sexually attractive than themselves, thus influencing the decision-making of males to their advantage. We tested this hypothesis in the Trinidadian guppy (Poecilia reticulata), a species with high levels of male sexual harassment. First, we confirmed that non-receptive females were harassed less when they were paired with a more sexually attractive (receptive) female than with another non-receptive female. We then found that, indeed, females exploit this as a strategy to reduce sexual harassment; non-receptive females actively preferred to associate with receptive over non-receptive females. Importantly, when given access only to chemosensory cues, non-receptive females still showed this preference, suggesting that they use information from chemical cues to assess the sexual attractiveness of potential female partners. Receptive females in contrast showed no such preferences. Our results demonstrate that females can decrease male harassment by associating with females that are more sexually attractive than themselves and that they perform active partner choices based on this relative attractiveness. We propose that this strategy is likely to represent an important pathway by which females can construct social niches that influence the decision-making of others to their advantage; in this case, to reduce the sexual harassment they experience.

  9. Examining the Development and Sexual Behavior of Adolescent Males

    PubMed Central

    Ott, Mary A.

    2010-01-01

    A careful examination of young men's sexuality by health professionals in pediatrics, primary care and reproductive health is foundational to adolescent male sexual health and healthy development. Through a review of existing literature, this article provides background and a developmental framework for sexual health services for adolescent boys. The article first defines and provides an overview of adolescent boys’ sexual health, and then discusses developmentally focused research on the following topics: (1) early romantic relationships and the evolution of power and influence within these relationships; (2) developmental “readiness” for sex and curiosity; (3) boys’ need for closeness and intimacy; (4) adopting codes of masculinity; (5) boys’ communicating about sex; and (6) contextual influences from peers, families, and providers. This article concludes by examining the implications of these data for sexual health promotion efforts for adolescent males, including HPV vaccination. PMID:20307842

  10. Simple Y-autosomal incompatibilities cause hybrid male sterility in reciprocal crosses between Drosophila virilis and D. americana.

    PubMed

    Sweigart, Andrea L

    2010-03-01

    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 F(1) hybrid males are perfectly fertile. Second, later generation (backcross and F(2)) 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.

  11. Measuring Love: Sexual Minority Male Youths' Ideal Romantic Characteristics.

    PubMed

    Bauermeister, José A; Johns, Michelle M; Pingel, Emily; Eisenberg, Anna; Santana, Matt Leslie; Zimmerman, Marc

    2011-04-01

    Research examining how sexual minorities characterize love within same-sex relationships is scarce. In this study, we examined the validity of Sternberg's Triangular Theory of Love in a sample of sexual minority male youth (N = 447). To test the adequacy of the theory for our population, we examined the psychometric properties of the Triadic Love Scale (TLS) and tested whether the three underlying constructs of the theory (Intimacy, Passion, and Commitment) emerged when participants were asked to consider their ideal relationship with another man. Using confirmatory factor analysis (CFA), we found support for the three-factor solution to characterize sexual minority male youths' ideal romantic relationship, after minimizing item cross-loadings and adapting the content of the Passion subscale. We discuss the implications of our findings regarding the measurement of the TLS among sexual minority male youth and propose ways to enhance its measurement in future research.

  12. Masculinity in adolescent males' early romantic and sexual heterosexual relationships.

    PubMed

    Bell, David L; Rosenberger, Joshua G; Ott, Mary A

    2015-05-01

    There is a need to understand better the complex interrelationship between the adoption of masculinity during adolescence and the development of early romantic and sexual relationships. The purpose of this study was to describe features of adolescent masculinity and how it is expressed in the contexts of early to middle adolescent males' romantic and sexual relationships. Thirty-three 14- to 16-year-old males were recruited from an adolescent clinic serving a community with high sexually transmitted infection rates and were asked open-ended questions about their relationships-how they developed, progressed, and ended. Participants described a high degree of relationally oriented beliefs and behaviors related to romantic and sexual relationships, such as a desire for intimacy and trust. The males also described a more limited degree of conventionally masculine beliefs and behaviors. These beliefs and behaviors often coexisted or overlapped. Implications for the clinical care of similar groups of adolescents are described.

  13. Selection and characterization of a novel photoperiod-sensitive male sterile line in upland cotton.

    PubMed

    Ma, Jianhui; Wei, Hengling; Liu, Ji; Song, Meizhen; Pang, Chaoyou; Wang, Long; Zhang, Wenxiang; Fan, Shuli; Yu, Shuxun

    2013-07-01

    Upland cotton (Gossypium hirsutum L.) shows strong heterosis. However, heterosis is not widely utilized owing to the high cost of hybrid seed production. Creation of a photoperiod-sensitive genetic male sterile line could substantially reduce the cost of hybrid seed production in upland cotton. Such a mutant with virescent marker was found by space mutation in near-earth orbit and its traits had been stable after 4 years of selection in Anyang and Sanya, China. This mutant was fertile with an 11-12.5 h photoperiod when the temperature was higher than 21.5 °C and was sterile with a 13-14.5 h photoperiod. Genetic analysis indicated that both traits were controlled by a single recessive gene or two closely linked genes. Also, the cytological observations and transcriptome profiling analysis showed that the degradation of pollen grain cytoplasm should be the primary reason why the mutant line were male sterile under long-day conditions.

  14. Orexin mediates initiation of sexual behavior in sexually naive male rats, but is not critical for sexual performance.

    PubMed

    Di Sebastiano, Andrea R; Yong-Yow, Sabrina; Wagner, Lauren; Lehman, Michael N; Coolen, Lique M

    2010-08-01

    The hypothalamic neuropeptide orexin mediates arousal, sleep, and naturally rewarding behaviors, including food intake. Male sexual behavior is altered by orexin receptor-1 agonists or antagonists, suggesting a role for orexin-A in this naturally rewarding behavior. However, the specific role of endogenous orexin-A or B in different elements of male sexual behavior is currently unclear. Therefore, the current studies utilized markers for neural activation and orexin cell-specific lesions to test the hypothesis that orexin is critical for sexual motivation and performance in male rats. First, cFos expression in orexin neurons was demonstrated following presentation of a receptive or non-receptive female without further activation by different elements of mating. Next, the functional role of orexin was tested utilizing orexin-B conjugated saporin, resulting in orexin cell body lesions in the hypothalamus. Lesions were conducted in sexually naive males and subsequent sexual behavior was recorded during four mating trials. Lesion males showed shortened latencies to mount and intromit during the first, but not subsequent mating trials, suggesting lesions facilitated initiation of sexual behavior in sexually naive, but not experienced males. Likewise, lesions did not affect sexual motivation in experienced males, determined by runway tests. Finally, elevated plus maze tests demonstrated reduced anxiety-like behaviors in lesioned males, supporting a role for orexin in anxiety associated with initial exposure to the female in naive animals. Overall, these findings show that orexin is not critical for male sexual performance or motivation, but may play a role in arousal and anxiety related to sexual behavior in naive animals.

  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.

  16. 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.; Kaspi, R.; Taylor, P.; Shelly, T.

    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

  17. Quality of Sterile Male Tsetse after Long Distance Transport as Chilled, Irradiated Pupae

    PubMed Central

    Bassene, Mireille D.; Fall, Assane Gueye; Diouf, Thérèse A. R.; Sall, Baba; Vreysen, Marc J. B.; Rayaissé, Jean-Baptiste; Takac, Peter; Sidibé, Issa; Parker, Andrew G.; Mutika, Gratian N.; Bouyer, Jérémy; Gimonneau, Geoffrey

    2015-01-01

    Background Tsetse flies transmit trypanosomes that cause human and African animal trypanosomosis, a debilitating disease of humans (sleeping sickness) and livestock (nagana). An area-wide integrated pest management campaign against Glossina palpalis gambiensis has been implemented in Senegal since 2010 that includes a sterile insect technique (SIT) component. The SIT can only be successful when the sterile males that are destined for release have a flight ability, survival and competitiveness that are as close as possible to that of their wild male counterparts. Methodology/Principal Findings Tests were developed to assess the quality of G. p. gambiensis males that emerged from pupae that were produced and irradiated in Burkina Faso and Slovakia (irradiation done in Seibersdorf, Austria) and transported weekly under chilled conditions to Dakar, Senegal. For each consignment a sample of 50 pupae was used for a quality control test (QC group). To assess flight ability, the pupae were put in a cylinder filtering emerged flies that were able to escape the cylinder. The survival of these flyers was thereafter monitored under stress conditions (without feeding). Remaining pupae were emerged and released in the target area of the eradication programme (RF group). The following parameter values were obtained for the QC flies: average emergence rate more than 69%, median survival of 6 days, and average flight ability of more than 35%. The quality protocol was a good proxy of fly quality, explaining a large part of the variances of the examined parameters. Conclusions/Significance The quality protocol described here will allow the accurate monitoring of the quality of shipped sterile male tsetse used in operational eradication programmes in the framework of the Pan-African Tsetse and Trypanosomosis Eradication Campaign. PMID:26562521

  18. Normal male childhood and adolescent sexual interactions: implications for sexual orientation of the individual with intersex.

    PubMed

    Lee, Peter A; Houk, Christopher P

    2005-03-01

    Data provided by 24 adult men, 20 heterosexual and four homosexual, concerning parental, religious, geographic and explicit sexual innuendos, comments and childhood experiences are presented and discussed in an attempt to consider some of the multiple factors impacting the development of sexual orientation. All of the study subjects were normally developed males and were presumed to have been exposed to normal male levels of androgens prenatally. Since the experiences and perceptions reported are conditioned by a unique social environment that has been superimposed on a normal male typical prenatal CNS differentiation, the experiences of these men suggest that affirmation of masculinity, and openness in the realm of social and sexual interaction, may enhance the formation of a heterosexual orientation. Conversely, sexually explicit feedback with critical implications occurred commonly among the homosexual men, which they interpreted as implying an insufficient masculinity. Both innate factors and social influences impact sexual orientation; in some instances males appear to have been homosexual from early childhood onward, while in other cases there appears to have been some degree of conditioning and choice in sexual orientation. Regarding the intersexed male, this suggests that social interactions, particularly those provided by parents, have a major influence on the development of sexual orientation in the child, while all persons involved in these children's lives and particularly those who nurture must be prepared for any sexual orientation that develops.

  19. X-chromosome dosage affects male sexual behavior

    PubMed Central

    Bonthuis, Paul J.; Cox, Kimberly H.; Rissman, Emilie F.

    2012-01-01

    Sex differences in the brain and behavior are primarily attributed to dichotomous androgen exposure between males and females during neonatal development, as well as adult responses to gonadal hormones. Here we tested an alternative hypothesis and asked if sex chromosome complement influences male copulatory behavior, a standard behavior for studies of sexual differentiation. We used two mouse models with non-canonical associations between chromosomal and gonadal sex. In both models, we found evidence for sex chromosome complement as an important factor regulating sex differences in the expression of masculine sexual behavior. Counter intuitively, males with two X-chromosomes were faster to ejaculate and display more ejaculations than males with a single X. Moreover, mice of both sexes with two X-chromosomes displayed increased frequencies of mounts and thrusts. We speculate that expression levels of a yet to be discovered gene(s) on the X-chromosome may affect sexual behavior in mice and perhaps in other mammals. PMID:22349083

  20. Male Pseudoheterosexuality and Minimal Sexual Dysfunction

    ERIC Educational Resources Information Center

    Gutstadt, Joseph P.

    1976-01-01

    There is often a correlation between "pseudoheterosexuality" and minor sexual dysfunction. Insight alone is not sufficient to provide relief, but when the patient can be helped to a comfortable acceptance of his homosexual feelings as a normal and healthy facet of his personality, very often the dysfunction is relieved. (Author)

  1. A mutation in Thermosensitive Male Sterile 1, encoding a heat shock protein with DnaJ and PDI domains, leads to thermosensitive gametophytic male sterility in Arabidopsis.

    PubMed

    Yang, Ke-Zhen; Xia, Chuan; Liu, Xiao-Lei; Dou, Xiao-Ying; Wang, Wei; Chen, Li-Qun; Zhang, Xue-Qin; Xie, Li-Fen; He, Luyan; Ma, Xuan; Ye, De

    2009-03-01

    In most flowering plant species, pollination and fertilization occur during the hot summer, so plants must have evolved a mechanism that ensures normal growth of their pollen tubes at high temperatures. Despite its importance to plant reproduction, little is known about the molecular basis of thermotolerance in pollen tubes. Here we report the identification and characterization of a novel Arabidopsis gene, Thermosensitive Male Sterile 1 (TMS1), which plays an important role in thermotolerance of pollen tubes. TMS1 encodes a Hsp40-homologous protein with a DnaJ domain and an a_ERdj5_C domain found in protein disulfide isomerases (PDI). Purified TMS1 expressed in Escherichia coli (BL21 DE3) had the reductive activity of PDI. TMS1 was expressed in pollen grains, pollen tubes and other vegetative tissues, including leaves, stems and roots. Heat shock treatment at 37 degrees C increased its expression levels in growing pollen tubes as well as in vegetative tissues. A knockout mutation in TMS1 grown at 30 degrees C had greatly retarded pollen tube growth in the transmitting tract, resulting in a significant reduction in male fertility. Our study suggests that TMS1 is required for thermotolerance of pollen tubes in Arabidopsis, possibly by functioning as a co-molecular chaperone.

  2. Sexual selection of male parental care in giant water bugs

    PubMed Central

    Ohba, Shin-ya; Okuda, Noboru; Kudo, Shin-ichi

    2016-01-01

    Paternal care can be maintained under sexual selection, if it helps in attracting more mates. We tested the hypothesis in two giant water bug species, Appasus major and Appasus japonicus, that male parental care is sexually selected through female preference for caring males. Females were given an opportunity to choose between two males. In the first test of female mate choice, one male carried eggs on its back, while the other did not. The egg status was switched between these two males in the second test. The experiment revealed that females of both species preferred caring males (i.e. egg-bearing) to non-caring males. Nonetheless, the female mate preference for egg-bearing males was stronger in A. major than in A. japonicus. Our results suggest that sexual selection plays an important role in maintaining elaborate paternal care in giant water bugs, but the importance of egg-bearing by males in female mate choice varies among species. PMID:27293778

  3. How the Male Body Works Sexually

    MedlinePlus

    ... Cancer Sex and the Man With Cancer Cancer, Sex, and the Male Body Cancer and sex When you first found out you had cancer, ... remains. How a man’s body works The male sex organs A man’s genitals and sex organs are ...

  4. 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…

  5. Effects of Nuclear Genomes on Anther Development in Cytoplasmic Male Sterile Chicories (Cichorium intybus L.): Morphological Analysis

    PubMed Central

    Habarugira, Ildephonse; Hendriks, Theo; Quillet, Marie-Christine; Hilbert, Jean-Louis; Rambaud, Caroline

    2015-01-01

    The Cichorium intybus flower development in fertile, cytoplasmic male sterility (CMS 524) and various phenotypes carrying the 524 male sterile cytoplasm was investigated macroscopically and by light microscopy. The development was similar in fertile and in male sterile florets up to meiosis, and then it was affected in anther wall structure and pollen grain development in male sterile floret. In the male sterile plants, the tapetum intrusion after meiosis was less remarkable, the microspores started to abort at vacuolate stage, the connective tissue collapsed, and endothecium failed to expand normally and did not undergo cell wall lignification, which prevented anther opening since the septum and stomium were not disrupted. Crosses undertaken in order to introduce the CMS 524 into two different nuclear backgrounds gave rise to morphologically diversified progenies due to different nuclear-mitochondrial interactions. Macroscopic and cytological investigations showed that pollen-donor plants belonging to Jupiter population had potential capacity to restore fertility while the CC line could be considered as a sterility maintainer. PMID:25861678

  6. 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

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

    USGS Publications Warehouse

    Bergstedt, Roger A.; Twohey, Michael B.

    2005-01-01

    The parasitic sea lamprey (Petromyzon marinus) has been a serious pest since its introduction into the Great Lakes, where it contributed to severe imbalances in the fish communities by selectively removing large predators (Smith 1968; Christie 1974; Schneider et al.1996). Since the 1950s, restoration and maintenance of predator-prey balance has depended on the Great Lakes Fishery Commission (GLFC) sea lamprey management program. Initially, management relied primarily on stream treatments with a selective lampricide to kill larvae, on barriers to migration, and on trapping to remove potential spawners (Smith and Tibbles 1980). By the late 1970s, however, it was clear that the future of sea lamprey management lay in development of a larger array of control strategies, including more alternatives to lampricide applications (Sawyer 1980). Since then the only new alternative to chemical control to reach operational status is the release of sterilized male sea lampreys. Research on the concept began at the USGS, Hammond Bay Biological Station in Millersburg, MI (HBBS) during the 1970s (Hanson and Manion 1980). Development and evaluation continued through the 1980s, leading to the release of sterilized males in Great Lakes tributaries since 1991 (Twohey et al. 2003a). The objectives of this paper are 1) to review the implementation and evaluations of sterile-male-release technique (SMRT) as it is being applied against sea lampreys in the Great Lakes, 2) to review our current understanding of its efficacy, and 3) to identify additional research areas and topics that would increase either the efficacy of SMRT or expand its geographic potential for application.

  8. Tomato Male sterile 1035 is essential for pollen development and meiosis in anthers.

    PubMed

    Jeong, Hee-Jin; Kang, Jin-Ho; Zhao, Meiai; Kwon, Jin-Kyung; Choi, Hak-Soon; Bae, Jung Hwan; Lee, Hyun-Ah; Joung, Young-Hee; Choi, Doil; Kang, Byoung-Cheorl

    2014-12-01

    Male fertility in flowering plants depends on proper cellular differentiation in anthers. Meiosis and tapetum development are particularly important processes in pollen production. In this study, we showed that the tomato male sterile (ms10(35)) mutant of cultivated tomato (Solanum lycopersicum) exhibited dysfunctional meiosis and an abnormal tapetum during anther development, resulting in no pollen production. We demonstrated that Ms10(35) encodes a basic helix-loop-helix transcription factor that is specifically expressed in meiocyte and tapetal tissue from pre-meiotic to tetrad stages. Transgenic expression of the Ms10(35) gene from its native promoter complemented the male sterility of the ms10(35) mutant. In addition, RNA-sequencing-based transcriptome analysis revealed that Ms10(35) regulates 246 genes involved in anther development processes such as meiosis, tapetum development, cell-wall degradation, pollen wall formation, transport, and lipid metabolism. Our results indicate that Ms10(35) plays key roles in regulating both meiosis and programmed cell death of the tapetum during microsporogenesis.

  9. 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.

  10. 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

  11. Masculinity and the male role in sexual health.

    PubMed

    Shephard, B

    1996-01-01

    The program of action of the 1994 International Conference on Population and Development defines reproductive and sexual health as a state of complete physical, mental, and social well-being. Sexual health therefore involves enhancing the quality of life and personal relations. Programs to promote sexual health must address a broad range of social and personal problems. Reproductive health programs need to abandon their exclusive focus upon women to give attention and services to men, women, and couples. Male rights and duties, targeting men who act responsibly as heads of households, cultural models of masculinity, men's contempt of femininity, and recognition of homophobia and misogyny as the most powerful mechanisms of social repression are discussed. Sexual education programs, violence prevention programs, and education from the gender perspective all need to focus directly upon the themes of gender equality and sexual diversity.

  12. Assortative sexual mixing patterns in male?female and male?male partnerships in Melbourne, Australia: implications for HIV and sexually transmissible infection transmission.

    PubMed

    Chow, Eric P F; Read, Tim R H; Law, Matthew G; Chen, Marcus Y; Bradshaw, Catriona S; Fairley, Christopher K

    2016-07-29

    Background: Assortative mixing patterns have become a new and important focus in HIV/sexually transmissible infection (STI) research in recent years. There are very limited data on sexual mixing patterns, particularly in an Australian population. Methods: Male-female and male-male partnerships attending the Melbourne Sexual Health Centre (MSHC) between 2011 and 2014 were included. Correlation of age between two individuals within a partnership was examined by using Spearman's rank correlation. The Newman's assortativity coefficient was used as an aggregate quantitative measurement of sexual mixing for number of partners and condom use. Results: 1165 male-female and 610 male-male partnerships were included in the analysis. There was a strong positive correlation of age in both male-female (rho=0.709; P<0.001) and male-male partnerships (rho=0.553; P<0.001). The assortative mixing pattern for number of partners was similar in male-female (r=0.255; 95% CI: 0.221-0.289) and male-male partnerships (r=0.264; 95% CI: 0.218-0.309). There was a stronger assortative mixing pattern for condom use in male-male (r=0.517, 95% CI: 0.465-0.569) compared with male-female (r=0.382; 95% CI: 0.353-0.412) partnerships. Conclusion: Male-female and male-male partnerships have a high assortativity mixing pattern for age, number of partners and condom use. The sexual mixing pattern is not purely assortative, and hence it may lead to increased HIV and STI transmission in certain risk groups.

  13. Divergent sexual selection via male competition: ecology is key.

    PubMed

    Lackey, A C R; Boughman, J W

    2013-08-01

    Sexual selection and ecological differences are important drivers of speciation. Much research has focused on female choice, yet the role of male competition in ecological speciation has been understudied. Here, we test how mating habitats impact sexual selection and speciation through male competition. Using limnetic and benthic species of threespine stickleback fish, we find that different mating habitats select differently on male traits through male competition. In mixed habitat with both vegetated and open areas, selection favours two trait combinations of male body size and nuptial colour: large with little colour and small with lots of colour. This matches what we see in reproductively isolated stickleback species, suggesting male competition could promote trait divergence and reproductive isolation. In contrast, when only open habitat exists, selection favours one trait combination, large with lots of colour, which would hinder trait divergence and reproductive isolation. Other behavioural mechanisms in male competition that might promote divergence, such as avoiding aggression with heterospecifics, are insufficient to maintain separate species. This work highlights the importance of mating habitats in male competition for both sexual selection and speciation.

  14. Female and male undergraduates' attributions for sexual offending against children.

    PubMed

    Beling, J; Hudson, S M; Ward, T

    2001-01-01

    This study examined gender differences in undergraduates' attributions for child sex offending. One hundred and sixty-four undergraduates were asked to give the reasons why they think men sexually offend against children and to rate them using Benson's Attributional Scale across four dimensions: stability, locus, controllability and globality. A Grounded Theory methodology was applied to these reasons and a set of nine categories derived from the data. The results showed that undergraduates' reasons for child sexual abuse strongly parallel contemporary scientific theories of abuse, and that there were significant gender differences in the frequency with which participants cited various types of reasons given for sexual abuse. Females endorsed significantly more victim reasons than males, and also more power and control reasons than did males. In contrast, males endorsed significantly more sexual reasons for offending than did females. Furthermore, significant gender differences were found between the ways in which participants construed the reasons for sexual abuse, with females seeing the phenomenon as significantly more stable and internal than males. No significant gender differences were found on the dimensions of controllability and globality.

  15. Effects of rootstocks on cryotolerance and overwintering survivorship of genic male sterile lines in upland cotton (Gossypium hirsutum L.).

    PubMed

    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.

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

    PubMed

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

    2011-11-01

    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 F(2) populations derived from the crosses between 337S and five common wheat varieties were developed for genetic analysis. All F(1)'s were highly fertile while segregation occurred in the F(2) 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 F(2) generation.

  17. Sexual function in male patients with ankylosing spondylitis.

    PubMed

    Ozkorumak, E; Karkucak, M; Civil, F; Tiryaki, A; Ozden, G

    2011-01-01

    Sexuality is an important part of healthy life. Patients with ankylosing spondylitis (AS) may be vulnerable to sexual problems because of disease activity and comorbid emotional problems. However, sexuality is a scarcely studied subject in AS. The aim of this study is to compare patients with AS with healthy control. A total of 43 male patients, who referred to the Department of Physical Medicine and Rehabilitation Clinics of the Karadeniz Technical University Farabi Hospital between May 2010 and July 2010, and were diagnosed as AS according to modified New York criteria, were included in the study. Control group consisted of healthy 43 age- and sex-matched male individuals with normal inflammatory levels. The AS patients were compared in means of sociodemographic variables and sexual function with Glombok-Rust Sexual Satisfaction Scale (GRSSS) and clinical interview. Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) were used to determine anxiety and depression levels, respectively. The disease activity and functional conditions were evaluated with the Bath Ankylosing Spondylitis Functional Index (BASFI), the Bath Ankylosing Spondylitis Metrology Index (BASMI) and the Bath Ankylosing Spondylitis Disease Activity Index (BASDI). A total of 43 patients with AS and 43 healthy heterosexual male were included in the study. The total GRSSS score was significantly higher in patients with AS, whereas they also had significantly higher sexual complaint than healthy control. The diagnosis of sexual dysfunction according to DSM-IV was significantly higher in the patients with AS as well as depression and anxiety. In study group, GRSSS total score was modestly correlated with disease activity. The psychological status had close relation with sexual functions in AS. Overall assessment is required for complete evaluation in patients with AS.

  18. Genetic studies on cytoplasmic male sterility in maize. Progress report, April 15, 1990--April 14, 1992

    SciTech Connect

    Laughnan, J.R.

    1992-05-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  19. Somatic hybrids between Arabidopsis thaliana and cytoplasmic male-sterile radish (Raphanus sativus).

    PubMed

    Yamagishi, H; Glimelius, K

    2003-08-01

    Somatic hybrids were produced by protoplast fusion between Arabidopsis thaliana ecotype Columbia and a male-sterile radish line MS-Gensuke ( Raphanus sativus) with the Ogura cytoplasm. Forty-one shoots were differentiated from the regenerated calli and established as shoot cultures in vitro. About 20 of these shoots were judged to be hybrids based on growth characteristics and morphology. Molecular analyses of 11 shoots were performed, confirming the hybrid features. Of these 11 shoots, eight were established as rooted plants in the greenhouse. Polymerase chain reaction and randomly amplified polymorphic DNA analyses of the nuclear genomes of all analyzed shoots and plants confirmed that they contained hybrid DNA patterns. Their chromosome numbers also supported the hybrid nature of the plants. Investigations of the organelles in the hybrids revealed that the chloroplast (cp) genome was exclusively represented by radish cpDNA, while the mitochondrial DNA configuration showed a combination of both parental genomes as well as fragments unique to the hybrids. Hybrid plants that flowered were male-sterile independent of the presence of the Ogura CMS-gene orf138.

  20. 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...

  1. Mutation in CSA creates a new photoperiod-sensitive genic male sterile line applicable for hybrid rice seed production.

    PubMed

    Zhang, Hui; Xu, Chenxi; He, Yi; Zong, Jie; Yang, Xijia; Si, Huamin; Sun, Zongxiu; Hu, Jianping; Liang, Wanqi; Zhang, Dabing

    2013-01-02

    Rice is a major staple food worldwide. Making hybrid rice has proved to be an effective strategy to significantly increase grain yield. Current hybrid rice technologies rely on male sterile lines and have been used predominantly in indica cultivars. However, intrinsic problems exist in the implementation of these technologies, such as limited germplasms and unpredictable conversions from sterility to fertility in the field. Here, we describe a photoperiod-controlled male sterile line, carbon starved anther (csa), which contains a mutation in an R2R3 MYB transcription regulator of pollen development. This mutation was introduced into indica and japonica rice, and it rendered male sterility under short-day conditions and male fertility under long-day conditions in both lines. Furthermore, F(1) plants of csa and a restorer line JP69 exhibited heterosis (hybrid vigor), suggesting the feasibility of using this mutation to create hybrid rice. The csa-based photoperiod-sensitive male sterile line allows the establishment of a stable two-line hybrid system, which promises to have a significant impact on agriculture.

  2. 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.

  3. 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...

  4. 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.…

  5. Mass rearing history negatively affects mating success of male Anastrepha ludens (Diptera: Tephritidae) reared for sterile insect technique programs.

    PubMed

    Rull, Juan; Brunel, Odette; Mendez, Maria Elena

    2005-10-01

    Mating competitiveness and sterility induction into cohorts of wild Anastrepha ludens (Loew) (Diptera: Tephritidae) was compared among wild and laboratory flies reared for use in the sterile insect technique Mexican program. Laboratory flies stemming from an 11-yr-old bisexual strain were either not irradiated, irradiated at 3 krad (low dose), or irradiated at 8 krad. In 30 by 30 by 30-cm Plexiglas cages, where a cohort of laboratory flies (male and female) irradiated at different doses (0, 3, and 8 krad) was introduced with a cohort of wild flies, males and females of each type mated randomly among themselves. Compared with nonirradiated laboratory and wild males, irradiated males, irrespective of dose (3 or 8 krad), induced shorter refractory periods and greater mating frequency in wild females. Nevertheless, laboratory flies irradiated at a low dose induced greater sterility into cohorts of wild flies than laboratory flies irradiated at a high dose. In a 3 by 3 by 3-m walk-in cage, wild males gained significantly more matings with wild females than nonirradiated and irradiated laboratory males a finding that revealed a strong effect of strain on mating performance. Mating incompatibility of the laboratory strain might have obscured the effect of reduced irradiation doses on male mating performance in the walk-in cage. Our results highlight an urgent need to replace the A. ludens strain currently used by the Mexican fruit fly eradication campaign and at least suggest that reducing irradiation doses result in an increase in sterility induction in wild populations.

  6. Sexual arousal in sexually sluggish old male rats after oral administration of Eurycoma longifolia Jack.

    PubMed

    Ang, Hooi Hoon; Lee, Kheng Leng; Kiyoshi, Matsumoto

    2004-01-01

    Eurycoma longifolia Jack commonly known as Tongkat Ali in Malaysia, has been used in Malaysia to increase male virility and sexual prowess. The objective of this study is to evaluate sexual arousal in sexually sluggish old male rats, 24 months old and retired breeders, receiving 200, 400, or 800 mg/kg of various fractions of E. longifolia Jack, twice daily, for 10 days. Control rats received 3 ml/kg of normal saline. The aphrodisiac effect was monitored by the act of yawning and stretching because yawning, either alone or associated with stretching, is considered an ancestral vestige surviving throughout evolution that promotes sexual arousal. The results showed that 800 mg/kg of E. longifolia Jack increased yawning by 50% and stretching by 16.7% in sexually sluggish old male rats, by 676-719% and 31-336%, respectively, in sexually active male rats, and by 22-44% and 75-100%, respectively, in middle aged, 9 months old and retired breeders. We conclude that the results of this study support the folk use of this plant as an aphrodisiac.

  7. 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.

  8. Female, but not male, nematodes evolve under experimental sexual coevolution

    PubMed Central

    Fritzsche, K.; Timmermeyer, N.; Wolter, M.; Michiels, N. K.

    2014-01-01

    Coevolution between the sexes is often considered to be male-driven: the male genome is constantly scanned by selection for traits that increase relative male fertilization success. Whenever these traits are harmful to females, the female genome is scanned for resistance traits. The resulting antagonistic coevolution between the sexes is analogous to Red Queen dynamics, where adaptation and counteradaptation keep each other in check. However, the underlying assumption that male trait evolution precedes female trait counteradaptation has received few empirical tests. Using the gonochoristic nematode Caenorhabditis remanei, we now show that 20 generations of relaxed versus increased sexual selection pressure lead to female, but not to male, trait evolution, questioning the generality of a male-driven process. PMID:25339719

  9. Biochemical and molecular dissection of thermo-sensitive genetic male sterility in diploid cotton (Gossypium arboreum L).

    PubMed

    Sekhar, L; Khadi, B M; Patil, Rajesh S; Katageri, I S; Mukri, Ganapati

    2016-07-01

    Diploid cotton, due to its inherent problem of stamen brittleness, its found unsuitable for traditional method of hybrid seed production which involves hand emasculation followed by pollination. Due to shortfall in other methods viz., Genetic Male Sterility (GMS), as well as, Cytoplasmic Genetic Male Sterility (CGMS), hybrid seed production in diploid cotton becomes costly and thereby, covers less area among the total cotton grown area. Thermo-sensitive genetic male sterility, which overcomes the drawbacks of both GMS and CGMS can be an effective tool in coming years for hybrid cotton research. Understanding fertility and sterility variations, their relation with biochemical changes in plant is important before its application in plant breeding. Hence, the available TGMS line, Ga TGMS-3 obtained at Cotton Research Centre, UAS, Dharwad was studied for callase activity and markers associated with TGMS. The line Ga TGMS-3 had fertile anthers and showed less callase enzyme activity at pre-meiosis stage, high enzyme activity at tetrad releasing microspore stage and no callase activity during other stages. The counterpart TGMS sterile anthers displayed little higher callase activity at pre-meiosis stage, high activity at tetrad stage, but poor activity at tetrad releasing microspore stage. During tetrad stage, TGMS sterile anthers showed high callase enzyme activity giving every chance for early release of poorly developed microspores as compared to fertile anthers. At tetrad releasing microspores stage during which fertile anthers had strong callase enzyme activity led to microspores being released normally and developed normal pollen grains as compared to sterile anthers. The present investigation revealed that NAU2176, NAU2096 and BNL1227 primers can be used as tightly linked markers for TGMS trait, as evident from their differential expression in fertile and sterile anthers.

  10. A mitochondrial DNA sequence is associated with abnormal pollen development in cytoplasmic male sterile bean plants.

    PubMed Central

    Johns, C; Lu, M; Lyznik, A; Mackenzie, S

    1992-01-01

    Cytoplasmic male sterility (CMS) in common bean is associated with the presence of a 3-kb unique mitochondrial sequence designated pvs. The pvs sequence encodes at least two open reading frames (297 and 720 bp in length) with portions derived from the chloroplast genome. Fertility restoration by the nuclear restorer gene Fr results in the loss of this transcriptionally active unique region. We examined the effect of CMS (pvs present) and fertility restoration by Fr (pvs absent) on the pattern of pollen development in bean. In the CMS line, pollen aborted in the tetrad stage late in microgametogenesis. Microspores maintained cytoplasmic connections throughout pollen development, indicating aberrant or incomplete cytokinesis. Pollen-specific events associated with pollen abortion and fertility restoration imply that a gametophytic factor or event may be involved in CMS. In situ hybridization experiments suggested that significant reduction or complete loss of the mitochondrial sterility-associated sequence occurred in fertile pollen of F2 populations segregating for fertility. These observations support a model of fertility restoration by the loss of a mitochondrial DNA sequence prior to or during microsporogenesis/gametogenesis. PMID:1498602

  11. A cytoplasmic male sterility-associated mitochondrial peptide in common bean is post-translationally regulated.

    PubMed Central

    Sarria, R; Lyznik, A; Vallejos, C E; Mackenzie, S A

    1998-01-01

    Cytoplasmic male sterility in the common bean plant is associated with a dominant mitochondrial mutation designated pvs-or f 239 (for Phaseolus vulgaris sterility sequence open reading frame 239). The sequence is transcribed in both vegetative and reproductive tissues, but the translation product, ORF239, is present only in reproductive tissues. We present evidence to support a model of post-translational regulation of ORF239 expression based on the following observations. In organello translation experiments using purified mitochondria from young seedlings demonstrated accumulation of ORF239 only when a protease inhibitor was included. Proteolytic activity against ORF239 was observed in mitochondrial extracts fractionating with the mitochondrial inner membrane. The DNA sequence encoding a serine-type protease, similar to the lon protease gene of Escherichia coli, was cloned from the Arabidopsis genome. The expression product of this sequence demonstrated proteolytic activity against ORF239 in vitro, with features resembling the activity detected in mitochondrial inner membrane preparations. Antibodies generated against the overexpressed Lon homolog reduced proteolytic activity against ORF239 when added to mitochondrial extracts. Our data suggest that ORF239 was undetected in vegetative tissue due to rapid turnover by at least one mitochondrial protease that acts against ORF239 post-translationally. PMID:9668139

  12. Effect of inhibiting carnitine biosynthesis on male rat sexual performance.

    PubMed

    Dambrova, Maija; Cirule, Helena; Svalbe, Baiba; Zvejniece, Liga; Pugovichs, Osvalds; Zorenko, Tatjana; Kalvinsh, Ivars; Liepinsh, Edgars; Belozertseva, Irina

    2008-10-20

    l-carnitine has a documented role as a cofactor in cellular energy metabolism and fatty acid beta-oxidation pathways and it has also been considered to function in reproductive biology. We investigated whether decreasing concentrations of L-carnitine using an inhibitor of its biosynthesis, mildronate (3-(2,2,2-trimethylhydrazinium)-propionate), would influence the sexual behavior or sperm quality in male rats. Mildronate treatment induced a significant decrease in carnitine concentration and an increase in gamma-butyrobetaine (GBB) concentration in both plasma and testes extracts. However, the expression of carnitine palmitoyltransferase I in testes and testosterone concentration in plasma was not changed in mildronate treated rat. Behavioral experiments demonstrated that mildronate treatment did not decrease the sexual motivation in both sexually naive and sexually experienced rats. The densities of spermatozoa in the cauda epididymis, as well as motility, were unchanged after mildronate treatment at a dose of 100 mg/kg. In conclusion, our study provides experimental evidence that mildronate induces decrease in the free carnitine concentration in rat testes, but does not decrease the sexual activity or sperm quality of male rats.

  13. The Effects of False Physiological Feedback on Sexual Arousal in Sexually Dysfunctional and Functional Males

    DTIC Science & Technology

    1999-01-01

    of interest in sex , or even of an aversion to sexual activity . Table 1 summarizes the physical changes that occur in the male during the five stages... sex guilt, and greater endorsement of sex myths, specifically reported discomfort in communicating with their partner about sexual activities that...the private couple exercises occur during daily meetings between the couple and a dual- sex therapy team over a 2-week treatment period. These

  14. 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.

  15. Sexual Function in Males After Radiotherapy for Rectal Cancer

    SciTech Connect

    Bruheim, Kjersti; Guren, Marianne G.; Dahl, Alv A.; Skovlund, Eva; Balteskard, Lise; Carlsen, Erik; Fossa, Sophie D.; Tveit, Kjell Magne

    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.

  16. Delayed sexual maturity in males of Vespa velutina.

    PubMed

    Poidatz, Juliette; Bressac, Christophe; Bonnard, Olivier; Thiéry, Denis

    2017-03-01

    Vespa velutina var nigrithorax (lepelletier, 1835) is an invasive predator of bees accidentally introduced in France in 2004, and it is having a serious impact on apiculture and ecosystems. Studying the reproduction of an invasive species is key to assess its population dynamic. This study explores the sexual maturation of V. velutina males and the evolution of their fertility. The main studied parameters were physiologic (spermiogenesis, spermatogenesis) and anatomic (testes size and structure, head width). Two populations of males were described based on their emergence period: early males in early summer or classic males in autumn. Each testis has an average of 108 testicular follicles. Spermatogenesis is synchronous, with only one sperm production wave, and completed, on average, at 10.3 days after emergence with the degeneration of the testes. The sperm counts in seminal vesicles of mature males are 3×10(6) in October/November and 0.8× 10(6) in June. In comparison, females store 0.1 10(6) sperm in their spermathecae. The early males emerged from colonies made by fertilized queens. The reproductive potential of these early males seemed limited, and their function in the colony is discussed. The sperm stock evolution in autumn males suggests the occurrence of a reproductive pattern of male competition for the access to females and a single copulation per male. The synchronicity of male and foundress emergences and sexual maturation is of primary importance for the mating success and the future colony development. This article is protected by copyright. All rights reserved.

  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. Genome Barriers between Nuclei and Mitochondria Exemplified by Cytoplasmic Male Sterility

    PubMed Central

    Fujii, Sota; Toriyama, Kinya

    2008-01-01

    Since plants retain genomes of an extremely large size in mitochondria (200–2,400 kb), and mitochondrial protein complexes are comprised of chimeric structures of nuclear- and mitochondrial-encoded subunits, coordination of gene expression between the nuclei and mitochondria is indispensable for sound plant development. It has been well documented that the nucleus regulates organelle gene expression. This regulation is called anterograde regulation. On the other hand, recent studies have demonstrated that signals emitted from organelles regulate nuclear gene expression. This process is known as retrograde signaling. Incompatibility caused by genome barriers between a nucleus and foreign mitochondria destines the fate of pollen to be dead in cytoplasmic male sterility (CMS), and studies of CMS confirm that pollen fertility is associated with anterograde/retrograde signaling. This review summarizes the current perspectives in CMS and fertility restoration, mainly from the viewpoint of anterograde/retrograde signaling. PMID:18625609

  19. Sexual orientation in males and the evolution of anisogamy.

    PubMed

    Reed, Lawrence Ian

    2010-02-01

    How might homosexual orientation have evolved and been maintained? Several adaptationist explanations have been examined in attempt to reconcile the presence of same-sex sexual behaviors with traditional selection-based theory, showing little empirical support. The current paper presents a novel adaptationist explanation for the evolution and maintenance of same-sex sexual behaviors in males, both between- and within-species, related to the evolution of anisogamy. Under conditions of isogamy, sexual reproduction occurs between individuals with gametes of similar morphology. With the evolution of anisogamy came greater specificity on the types of individuals that would produce offspring when mated with (i.e. those with opposing gamete sizes). It is suggested that with this evolutionary change, a specified psychological adaptation orienting individuals primarily towards mating partners with newly opposing gamete sizes was then selected for. It is thus hypothesized that sexual orientation will vary along the anisogamy-isogamy continuum, with homosexual orientation being associated with closer approximations towards isogamy. This hypothesis leads to two specific predictions. First, in comparisons between species, the presence of same-sex sexual behaviors will be more likely to occur as sperm to egg ratios approach 1:1. Second, in comparisons within species, those individuals with greater sperm lengths will be more likely to exhibit same-sex sexual behaviors than those with lesser sperm lengths. Examination of the present hypothesis stands to greatly increase our knowledge of the selective forces shaping both biological and psychological evolution.

  20. Sexual orientation related differences in cortical thickness in male individuals.

    PubMed

    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.

  1. 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

  2. Childhood sexual abuse, sexual motives, and adolescent sexual risk-taking among males and females receiving child welfare services.

    PubMed

    Wekerle, Christine; Goldstein, Abby L; Tanaka, Masako; Tonmyr, Lil

    2017-01-27

    Childhood sexual abuse (CSA) is associated with multiple negative outcomes, including increased risky sexual behavior. To date, the majority of research on the relationship between CSA and risky sex in adolescence has been limited, with a lack of focus on males and youth receiving child welfare services. Participants in the current study were 297 youth (mean age=15.98; SD=1.01, 57.6% female) from the child welfare system who reported being sexually active at the time of the survey. CSA was associated with severity of other types of maltreatment for both genders, and exposure to intimate partner violence for females only. In general, males engaged in more sexual risk behaviors than females. Males with CSA had stronger motives to have sex for: (1) coping, (2) peer approval and (3) partner approval, as compared to non-CSA males; as well as (4) greater motives for partner and peer approval compared to females with CSA. Males with no CSA had stronger sexual motives for enhancement (e.g., feeling pleasure) compared to females with no CSA. Mediation analyses revealed a significant indirect effect for coping motives for males: CSA was associated with increased motives to use sex for coping which was associated with increased sexual risk-taking. These findings provide important information regarding the relationship between CSA and sexual risk-taking for child welfare sample and highlight coping with negative affect as a potential mechanism that underlies the CSA-risky sex relationship. It also encourages further consideration of motives for risk and resilience behaviors among youth.

  3. 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

  4. Male sexual disorders in Indian traditional medicine- a historical review.

    PubMed

    Padhi, M M

    1989-10-01

    The description of male sexual disorders by ancient authors of Indian medicine is praiseworthy. Effort has been made to describe the standard of approach with reference to certain books on Ayurveda and astrology. The development of administration of mineral medicines has added a new aspect in their treatment, but the description regarding their forms, etiopathogenesis, prognosis and the principle of treatment has remained unchanged. The opinions of various authors have been presented historically from vedic age up to the modern era. The present status of treatment and the role of Ayurveda in the treatment of sexual dysfunctions have been highlighted here.

  5. Effects of sex chromosome aneuploidy on male sexual behavior.

    PubMed

    Park, J H; Burns-Cusato, M; Dominguez-Salazar, E; Riggan, A; Shetty, S; Arnold, A P; Rissman, E F

    2008-08-01

    Incidence of sex chromosome aneuploidy in men is as high as 1:500. The predominant conditions are an additional Y chromosome (47,XYY) or an additional X chromosome (47,XXY). Behavioral studies using animal models of these conditions are rare. To assess the role of sex chromosome aneuploidy on sexual behavior, we used mice with a spontaneous mutation on the Y chromosome in which the testis-determining gene Sry is deleted (referred to as Y(-)) and insertion of a Sry transgene on an autosome. Dams were aneuploid (XXY(-)) and the sires had an inserted Sry transgene (XYSry). Litters contained six male genotypes, XY, XYY(-), XXSry, XXY(-)Sry, XYSry and XYY(-)Sry. In order to eliminate possible differences in levels of testosterone, all of the subjects were castrated and received testosterone implants prior to tests for male sex behavior. Mice with an additional copy of the Y(-) chromosome (XYY(-)) had shorter latencies to intromit and achieve ejaculations than XY males. In a comparison of the four genotypes bearing the Sry transgene, males with two copies of the X chromosome (XXSry and XXY(-)Sry) had longer latencies to mount and thrust than males with only one copy of the X chromosome (XYSry and XYY(-)Sry) and decreased frequencies of mounts and intromissions as compared with XYSry males. The results implicate novel roles for sex chromosome genes in sexual behaviors.

  6. Effects of sex chromosome aneuploidy on male sexual behavior

    PubMed Central

    Park, J. H.; Burns-Cusato, M.; Dominguez-Salazar, E.; Riggan, A.; Shetty, S.; Arnold, A. P.; Rissman, E. F.

    2008-01-01

    Incidence of sex chromosome aneuploidy in men is as high as 1:500. The predominant conditions are an additional Y chromosome (47,XYY) or an additional X chromosome (47,XXY). Behavioral studies using animal models of these conditions are rare. To assess the role of sex chromosome aneuploidy on sexual behavior, we used mice with a spontaneous mutation on the Y chromosome in which the testis-determining gene Sry is deleted (referred to as Y−) and insertion of a Sry transgene on an autosome. Dams were aneuploid (XXY−) and the sires had an inserted Sry transgene (XYSry). Litters contained six male genotypes, XY, XYY−, XXSry, XXY−Sry, XYSry and XYY−Sry. In order to eliminate possible differences in levels of testosterone, all of the subjects were castrated and received testosterone implants prior to tests for male sex behavior. Mice with an additional copy of the Y− chromosome (XYY−) had shorter latencies to intromit and achieve ejaculations than XY males. In a comparison of the four genotypes bearing the Sry transgene, males with two copies of the X chromosome (XXSry and XXY−Sry) had longer latencies to mount and thrust than males with only one copy of the X chromosome (XYSry and XYY−Sry) and decreased frequencies of mounts and intromissions as compared with XYSry males. The results implicate novel roles for sex chromosome genes in sexual behaviors. PMID:18363850

  7. Sexual characteristics and spermatogenesis in males of the parthenogenetic gecko Lepidodactylus lugubris (Reptilia, Gekkonidae).

    PubMed

    Röll, Beate; von Düring, Monika U G

    2008-01-01

    Obligately parthenogenetic lizards usually are all-female populations of hybrids producing diploid oocytes by premeiotic endomitosis and quasi-normal meiosis. In an all-female strain of the gekkonid lizard Lepidodactylus lugubris several phenotypic males arose spontaneously. The sexual characteristics of these males were studied using light and electron microscopy and compared with normal males of the bisexual genus Lygodactylus. Emphasis was layed on morphology of seminiferous tubules, occurrence of spermatogenic stages and ultrastructure of spermatozoa. The phenotypic males possessed preanal pores filled with secretions and a sexual nephric segment which were exactly the same as in normal, reproductively active males. In the testes, density and morphology of non-spermatogenic cell types, the Leydig and Sertoli cells, indicate a normal production of testicular testosterone and a normal function of the blood-testis barrier, respectively. Both in the normal and the phenotypic males, all meiotic cell types of spermatogenesis can be recognised in the seminiferous tubules and are apparently identical, indicating a normal meiosis without impairment in the phenotypic males. In contrast, the differentiation process of spermatids is markedly disturbed in the phenotypic males of L. lugubris. In the normal male, spermiogenesis results in mature spermatids and spermatozoa with small elongated nuclei, an acrosomal complex, and a flagellar tail possessing one axoneme. Spermatozoa fill both the lumen of most seminiferous tubules and the lumina of ductus epididymidis and ductus deferens. In the phenotypic male, spermiogenesis results in seemingly normal spermatids and in spermatozoa with large, non-elongated, deformed nuclei and/or irregular tails possessing more than one axoneme. Both the lumen of most seminiferous tubules and the lumina of the ductus epididymidis and the ductus deferens contain relatively few spermatozoa. We suggest that the phenotypic males inherited the

  8. QTL involved in the partial restoration of male fertility of C-type cytoplasmic male sterility in maize.

    PubMed

    Kohls, Susanne; Stamp, Peter; Knaak, Carsten; Messmer, Rainer

    2011-07-01

    Partial restoration of male fertility limits the use of C-type cytoplasmic male sterility (C-CMS) for the production of hybrid seeds in maize. Nevertheless, the genetic basis of the trait is still unknown. Therefore, the aim to this study was to identify genomic regions that govern partial restoration by means of a QTL analysis carried out in an F(2) population (n = 180). This population was derived from the Corn Belt inbred lines B37C and K55. F(2)BC(1) progenies were phenotyped at three locations in Switzerland. Male fertility was rated according to the quality and number of anthers as well as the anthesis-silking interval. A weak effect of environment on the expression of partial restoration was reflected by high heritabilities of all fertility-related traits. Partial restoration was inherited like an oligogenic trait. Three major QTL regions were found consistently across environments in the chromosomal bins 2.09, 3.06 and 7.03. Therefore, a marker-assisted counter-selection of partial restoration is promising. Minor QTL regions were found on chromosomes 3, 4, 5, 6 and 8. A combination of partial restorer alleles at different QTL can lead to full restoration of fertility. The maternal parent was clearly involved in the partial restoration, because the restorer alleles at QTL in bins 2.09, 6.04 and 7.03 originated from B37. The three major QTL regions collocated with other restorer genes of maize, a phenomenon, which seems to be typical for restorer genes. Therefore, a study of the clusters of restorer genes in maize could lead to a better understanding of their evolution and function. In this respect, the long arm of chromosome 2 is particularly interesting, because it harbors restorer genes for the three major CMS systems (C, T and S) of maize.

  9. Influence of HIV positive status on sexual behavior among males.

    PubMed

    Ventura-Filipe, E M; Newman, S P

    1998-12-01

    Findings are presented from a cross-sectional study comparing the sexual behavior of HIV-seronegative and HIV-seropositive men with male and female sex partners, with particular focus upon the practice of safer sex in both groups of men. The 150 HIV-seronegative and 86 HIV-seropositive participating males were recruited between August 1994 and February 1995 from public health centers in the state of Sao Paulo, Brazil, where they responded to a questionnaire. The men were 15-69 years old, of mean age 30 years. 78% were single, 14.4% were married/living together, 6.4% were separated/divorced, and 1.3% were widowers. 36% defined themselves as heterosexuals, 11.4% as bisexuals, and 36.4% as homosexuals, while 16.1% used other expressions. Compared to HIV-seronegative men, a smaller proportion of HIV-seropositive men had sexual contact with regular female partners and engaged in vaginal intercourse with that type of partner. Similarly, a smaller proportion of HIV-seropositive men engaged in overall sexual activity and reported a lower frequency of penetrative sexual practices. A high level of condom use with male and female sex partners was identified with no significant differences being found between the 2 serostatus groups. However, some risky sexual behavior was identified, especially with regular partners, suggesting that some men were continuing to have unsafe sex. HIV prevention programs should encourage both HIV-seronegative and HIV-seropositive men to practice safer sex.

  10. Sexual selection against deleterious mutations via variable male search success

    PubMed Central

    MacLellan, Kelsie; Whitlock, Michael C.; Rundle, Howard D.

    2009-01-01

    In many species, successful mating requires the initial step of actively searching for and locating a female. The overall health or condition of a male is likely to affect their ability to do this, making search effort a potentially important component of sexual fitness that may have important consequences for population mean fitness. We investigated the potential population genetic consequences of search effort using 10 populations of Drosophila melanogaster, each fixed for a different recessive mutation with a visible phenotypic effect. Mate choice trials were conducted in arenas of varying size, requiring different levels of search ability. Sexual selection against mutant males was stronger when increased search effort was included than when it was excluded. Varying abilities to find mates can substantially increase the strength of selection against deleterious alleles. PMID:19625301

  11. Tapetum-specific expression of a cytoplasmic orf507 gene causes semi-male sterility in transgenic peppers

    PubMed Central

    Ji, Jiao-Jiao; Huang, Wei; Li, Zheng; Chai, Wei-Guo; Yin, Yan-Xu; Li, Da-Wei; Gong, Zhen-Hui

    2015-01-01

    Though cytoplasmic male sterility (CMS) in peppers is associated with the orf507 gene, definitive and direct evidence that it directly causes male sterility is still lacking. In this study, differences in histochemical localization of anther cytochrome c oxidase between the pepper CMS line and maintainer line were observed mainly in the tapetal cells and tapetal membrane. Inducible and specific expression of the orf507 gene in the pepper maintainer line found that transformants were morphologically similar to untransformed and transformed control plants, but had shrunken anthers that showed little dehiscence and fewer pollen grains with lower germination rate and higher naturally damaged rate. These characters were different from those of CMS line which does not produce any pollen grains. Meanwhile a pollination test using transformants as the male parent set few fruit and there were few seeds in the limited number of fruits. At the tetrad stage, ablation of the tapetal cell induced by premature programmed cell death (PCD) occurred in the transformants and the microspores were distorted and degraded at the mononuclear stage. Stable transmission of induced semi-male sterility was confirmed by a test cross. In addition, expression of orf507 in the maintainer lines seemed to inhibit expression of atp6-2 to a certain extent, and lead to the increase of the activity of cytochrome c oxidase and the ATP hydrolysis of the mitochondrial F1Fo-ATP synthase. These results introduce the premature PCD caused by orf507 gene in tapetal cells and semi-male sterility, but not complete male sterility. PMID:25954296

  12. Sexual orientation of male mouse offspring prenatally exposed to ethanol.

    PubMed

    Watabe, T; Endo, A

    1994-01-01

    Pregnant mice were intubated with either low (2 g/kg) or high (4 g/kg) dose of ethanol twice daily throughout the last third of the gestational period (from dg14 to dg18: gestational day; plug positive = dg 0). Ninety days after birth, the sexual orientation test was conducted on male offspring. This test was designed to observe a two-choice preference for either male or female partners in a setting in which the test animal could move freely between the two incentive compartments within which a stud male and an estrous female had been placed. We found that young adult males that had been exposed to ethanol prenatally have a decreased preference for the opposite sex and an increased preference for the same sex as a partner, although their physical development was apparently unaffected.

  13. SRY alone can induce normal male sexual differentiation

    SciTech Connect

    Lopez, M.; Torres, L.; Cervantes, A.

    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.

  14. 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,...

  15. Comparative studies of mitochondrial proteomics reveal an intimate protein network of male sterility in wheat (Triticum aestivum L.).

    PubMed

    Wang, Shuping; Zhang, Gaisheng; Zhang, Yingxin; Song, Qilu; Chen, Zheng; Wang, Junsheng; Guo, Jialin; Niu, Na; Wang, Junwei; Ma, Shoucai

    2015-10-01

    Plant male sterility has often been associated with mitochondrial dysfunction; however, the mechanism in wheat (Triticum aestivum L.) has not been elucidated. This study set out to probe the mechanism of physiological male sterility (PHYMS) induced by the chemical hybridizing agent (CHA)-SQ-1, and cytoplasmic male sterility (CMS) of wheat at the proteomic level. A total of 71 differentially expressed mitochondrial proteins were found to be involved in pollen abortion and further identified by MALDI-TOF/TOF MS (matrix-assisted laser desorption/ionization-time of fight/time of flight mass spectrometry). These proteins were implicated in different cellular responses and metabolic processes, with obvious functional tendencies toward the tricarboxylic acid cycle, the mitochondrial electron transport chain, protein synthesis and degradation, oxidation stress, the cell division cycle, and epigenetics. Interactions between identified proteins were demonstrated by bioinformatics analysis, enabling a more complete insight into biological pathways involved in anther abortion and pollen defects. Accordingly, a mitochondria-mediated male sterility protein network in wheat is proposed; this network was further confirmed by physiological data, RT-PCR (real-time PCR), and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling) assay. The results provide intriguing insights into the metabolic pathway of anther abortion induced by CHA-SQ-1 and also give useful clues to identify the crucial proteins of PHYMS and CMS in wheat.

  16. Sterility introduced by release of genetically altered males to a domestic population of Aedes aegypti at the Kenya coast.

    PubMed

    McDonald, P T; Hausermann, W; Lorimer, N

    1977-05-01

    The release of males heterozygous for one or two sex-linked translocations was effective in introducing a high level of sterility into a domestic population of Aedes aegypti at a Rabai village. The effect of the releases continued for several weeks after the release period.

  17. Capture of Anastrepha suspensa and sterile male Ceratitis capitata (Diptera: Tephritidae) in multilure traps versus phase 4 traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field trials were conducted in south Florida to compare capture of wild Caribbean fruit flies, Anastrepha suspensa (Loew), and sterile male Mediterranean fruit flies, Ceratitis capitata (Wiedemann), in Multilure traps, which are McPhail-type traps that use an aqueous solution to retain attracted fli...

  18. Characterization of an RNase Z nonsense mutation identified exclusively in environment-conditioned genic male sterile rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two-line system that is becoming more and more important for development of rice hybrids depends on environmentally conditioned genic male sterility (EGMS) due to either photoperiod (PGMS), or temperature (TGMS), or both (PTGMS). Up to 18 EGMS genes have been mapped with two being cloned, but contro...

  19. 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...

  20. The marsupial male: a role model for sexual development.

    PubMed

    Renfree, M B; Harry, J L; Shaw, G

    1995-11-29

    Sexual differentiation in male marsupials has many similarities with that of eutherians. Marsupials have an XX-XY sex determining mechanism, and have a homologue of the testis-determining SRY gene on their Y-chromosome. However, the development pattern of SRY gene expression is different from the mouse in that it is expressed for a much longer period. SRY is expressed in a range of non-gonadal tissues in male pouch young and adults which is similar to the human pattern, and raises questions as to its particular role(s) in sexual differentiation. Similarly Müllerian inhibiting substance (MIS) is produced in the developing testis over a longer period than in the mouse. Since ovaries cultured with MIS or transplanted into male recipient pouch young develop tubular structures, MIS may induce Sertoli cell formation. Testosterone is produced by the neonatal testis, and this stimulates Wolffian duct development to form the vas deferens and epididymis. Virilization of urogenital sinus is also androgen-dependent. However, virilization of the prostate and phallus occurs more than three weeks after the onset of testosterone production, suggesting that the timing of this may be regulated by delayed activation of the androgen receptor pathway. Unlike in eutherians, differentiation of the scrotum and mammary glands is not dependent on testicular hormones, but is independently regulated by an X-linked genetic mechanism. Clearly marsupials provide a unique perspective to help us clarify the mechanisms underlying sexual development in all mammals.

  1. Male-to-Male Sexual Transmission of Zika Virus--Texas, January 2016.

    PubMed

    Deckard, D Trew; Chung, Wendy M; Brooks, John T; Smith, Jessica C; Woldai, Senait; Hennessey, Morgan; Kwit, Natalie; Mead, Paul

    2016-04-15

    Zika virus infection has been linked to increased risk for Guillain-Barré syndrome and adverse fetal outcomes, including congenital microcephaly. In January 2016, after notification from a local health care provider, an investigation by Dallas County Health and Human Services (DCHHS) identified a case of sexual transmission of Zika virus between a man with recent travel to an area of active Zika virus transmission (patient A) and his nontraveling male partner (patient B). At this time, there had been one prior case report of sexual transmission of Zika virus. The present case report indicates Zika virus can be transmitted through anal sex, as well as vaginal sex. Identification and investigation of cases of sexual transmission of Zika virus in nonendemic areas present valuable opportunities to inform recommendations to prevent sexual transmission of Zika virus.

  2. Evaluation of strategies for the release of male sea lampreys (Petromyzon marinus) in Lake Superior for a proposed sterile-male-release program

    USGS Publications Warehouse

    Kaye, C.A.; Heinrich, J.W.; Genovese, J.H.; Hanson, L.H.; McDonald, R.B.; Slade, J.W.; Swink, W.D.

    2003-01-01

    Successful implementation of a sea lamprey (Petromyzon marinus) control technique that uses sterilized males to reduce reproduction presently depends on the importation of large numbers of males outside of the target population. Strategies were examined for releasing male sea lampreys from Lakes Michigan and Huron into the Lake Superior spawning population and the ability of these introduced males to compete with resident males and spawn with resident females. During 1987, 553 (9%) of 6,324 imported fertile males released at 12 shoreline and one offshore site in Lake Superior were recaptured. Most remained within 20 km of the release site and entered the first stream encountered. During 1988, 393 (18%) of 2,208 imported fertile males released directly into three spawning rivers were recaptured. In both cases, animals released early during the spawning run were more likely to be recaptured than those released later. Introduced males successfully competed with resident males and spawned with resident females. Demonstrating that male sea lampreys could reproduce successfully when relocated supported subsequent large-scale field trials of the sterile-male-release technique.

  3. 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...

  4. Cytological and comparative proteomic analyses on male sterility in Brassica napus L. induced by the chemical hybridization agent monosulphuron ester sodium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 i...

  5. Spatial mobility, alcohol use, sexual behavior and sexual health among males in India.

    PubMed

    Gupta, Kamla; Vaidehi, Y; Majumder, Nabanita

    2010-08-01

    This paper examines the linkages of permanent migration, temporary mobility and alcohol consumption with risky sexual behavior and sexually transmitted infections (STIs) including HIV infection among males in India using a nationally representative dataset. The study shows that non-migrant men and migrant men do not differ significantly in any indicator of risky sexual behavior and STIs. Temporary long duration mobile men reported significantly more often than the non-mobile men or short duration mobile men that they had sex with multiple sex partners during their lifetime as well as sex with a high risk partner and had paid sex in the 12 months preceding the survey. Males who drank alcohol almost every day notwithstanding with their migration or mobility status were most prone to lifelong as well as more recent sexual risk behavior. Controlling for sociodemographic characteristics long duration mobile men and men who used alcohol almost daily had higher sexual risk behaviors and STI infections. Further migration and mobility did not show any significant relationship with tested HIV prevalence among males in India, controlling for sociodemographic characteristics. Males who had lifetime multiple sex partners were at the highest risk of tested HIV infection controlling for sociodemographic characteristics, migration, mobility, alcohol use and STI infection. Interventions focusing on HIV prevention in India need to target both non-migrant and migrant men, particularly those who drink alcohol more frequently or daily. Targeted interventions are required for temporary mobile men, particularly for those mobile men who have to stay away from their homes continuously for a longer duration. Long duration mobile men are most prone to regular alcohol use and risky sexual behavior.

  6. Transposon Tagging of a Male-Sterility, Female-Sterility Gene, St8, Revealed that the Meiotic MER3 DNA Helicase Activity Is Essential for Fertility in Soybean

    PubMed Central

    Baumbach, Jordan; Pudake, Ramesh N.; Johnson, Callie; Kleinhans, Kaylin; Ollhoff, Alexandrea; Palmer, Reid G.; Bhattacharyya, Madan K.; Sandhu, Devinder

    2016-01-01

    The W4 locus in soybean encodes a dihydroflavonol-4-reductase (DFR2) that regulates pigmentation patterns in flowers and hypocotyl. The mutable w4-m allele that governs variegated flowers has arisen through insertion of a CACTA-type transposable element, Tgm9, in DFR2. In the w4-m line, reversion from variegated to purple flower indicates excision of Tgm9, and its insertion at a new locus. Previously, we have identified a male-sterile, female-sterile mutant among the selfed progenies of a revertant plant carrying only purple flowers. Co-segregation between Tgm9 and the sterility phenotype suggested that the mutant was generated by insertion of Tgm9 at the St8 locus. The transposon was localized to exon 10 of Glyma.16G072300 that shows high identity to the MER3 DNA helicase involved in crossing over. Molecular analysis of fertile branches from two independent revertant plants confirmed precise excision of Tgm9 from the st8 allele, which restored fertility. In soybean, the gene is expressed in flower-buds, trifoliate leaves and stem. Phylogenetic analysis placed St8 in a clade with the Arabidopsis and rice MER3 suggesting that St8 is most likely the orthologous MER3 soybean gene. This study established the utility of Tgm9 in gene identification as well as in forward and reverse genetics studies. PMID:26930200

  7. Maternal treatment with picrotoxin in late pregnancy improved female sexual behavior but did not alter male sexual behavior of offspring.

    PubMed

    Bernardi, Maria M; Scanzerla, Kayne K; Chamlian, Mayra; Teodorov, Elizabeth; Felicio, Luciano F

    2013-08-01

    Previous studies from our laboratory investigated the effects of picrotoxin (PT), a γ-aminobutyric acid receptor antagonist administered during several perinatal periods, on the sexual behavior of male and female rats. We observed that the time of perinatal exposure to PT is critical to determine either facilitation or impairment of sexual behavior. The present study evaluated the effects of prenatal administration of a single dose of PT on gestation day 18 of dams (the first critical period of male brain sexual differentiation) on sexual behavior of male and female offspring. Thus, female Wistar rats were mated with males and, on gestation day 18, received 0.6 mg/kg of PT or 0.9% saline solution subcutaneously. On postnatal day 1, the offspring were weighed and several measures of sexual development were assessed. The sexual behaviors and the general activity in the open field of adult male and ovariectomized, hormone-treated female rats were observed. On comparison with the control group, maternal PT treatment: (i) did not alter the maternal weight, pup weight, anogenital distance, or male and female general activity; (ii) increased female sexual behavior, that is, decreased the latencies to first mount, first lordosis, and tenth lordosis, and the percentage of females presenting lordosis; and (iii) did not alter male sexual behavior. It is suggested that prenatal PT exposure interfered with epigenetic mechanisms related to the development of sex differences in the brain, leading to the observed sexually dimorphic effects on sexual behavior.

  8. Role of anxiety in subordinate male mice sexual behavior.

    PubMed

    D'Amato, F R; Pavone, F

    1992-09-01

    Dominant and subordinate male mice behave differently when exposed to a female, with subordinates showing impairment of their sexual performance in the presence of the male antagonist. In the present study, we investigate whether these rank-related behavioral differences can be modified by an anxiolytic treatment. In a first experiment, diazepam (0.25 mg/kg) improves the performance of subordinate mice toward the female, as shown by the increase of proxemic behavior, anogenital sniffing, and social grooming of the female. Social grooming of the female is the only behavior modified by a higher dose of the anxiolytic drug (0.5 mg/kg). A second experiment, in which dominant and isolated mice are subjected to the same experimental procedure, demonstrates that social behavior of these two classes of males is not affected by the pharmacological treatment. The results are discussed in terms of the advantages of using subordinate males in such a sexual context as a model for the study of anxiolytic drugs.

  9. Organelle Simple Sequence Repeat Markers Help to Distinguish Carpelloid Stamen and Normal Cytoplasmic Male Sterile Sources in Broccoli.

    PubMed

    Shu, Jinshuai; Liu, Yumei; Li, Zhansheng; Zhang, Lili; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao

    2015-01-01

    We previously discovered carpelloid stamens when breeding cytoplasmic male sterile lines in broccoli (Brassica oleracea var. italica). In this study, hybrids and multiple backcrosses were produced from different cytoplasmic male sterile carpelloid stamen sources and maintainer lines. Carpelloid stamens caused dysplasia of the flower structure and led to hooked or coiled siliques with poor seed setting, which were inherited in a maternal fashion. Using four distinct carpelloid stamens and twelve distinct normal stamens from cytoplasmic male sterile sources and one maintainer, we used 21 mitochondrial simple sequence repeat (mtSSR) primers and 32 chloroplast SSR primers to identify a mitochondrial marker, mtSSR2, that can differentiate between the cytoplasm of carpelloid and normal stamens. Thereafter, mtSSR2 was used to identify another 34 broccoli accessions, with an accuracy rate of 100%. Analysis of the polymorphic sequences revealed that the mtSSR2 open reading frame of carpelloid stamen sterile sources had a deletion of 51 bases (encoding 18 amino acids) compared with normal stamen materials. The open reading frame is located in the coding region of orf125 and orf108 of the mitochondrial genomes in Brassica crops and had the highest similarity with Raphanus sativus and Brassica carinata. The current study has not only identified a useful molecular marker to detect the cytoplasm of carpelloid stamens during broccoli breeding, but it also provides evidence that the mitochondrial genome is maternally inherited and provides a basis for studying the effect of the cytoplasm on flower organ development in plants.

  10. Pheromone evolution and sexual behavior in Drosophila are shaped by male sensory exploitation of other males

    PubMed Central

    Ng, Soon Hwee; Shankar, Shruti; Shikichi, Yasumasa; Akasaka, Kazuaki; Mori, Kenji; Yew, Joanne Y.

    2014-01-01

    Animals exhibit a spectacular array of traits to attract mates. Understanding the evolutionary origins of sexual features and preferences is a fundamental problem in evolutionary biology, and the mechanisms remain highly controversial. In some species, females choose mates based on direct benefits conferred by the male to the female and her offspring. Thus, female preferences are thought to originate and coevolve with male traits. In contrast, sensory exploitation occurs when expression of a male trait takes advantage of preexisting sensory biases in females. Here, we document in Drosophila a previously unidentified example of sensory exploitation of males by other males through the use of the sex pheromone CH503. We use mass spectrometry, high-performance liquid chromatography, and behavioral analysis to demonstrate that an antiaphrodisiac produced by males of the melanogaster subgroup also is effective in distant Drosophila relatives that do not express the pheromone. We further show that species that produce the pheromone have become less sensitive to the compound, illustrating that sensory adaptation occurs after sensory exploitation. Our findings provide a mechanism for the origin of a sex pheromone and show that sensory exploitation changes male sexual behavior over evolutionary time. PMID:24516141

  11. Suicide attempts among sexual-minority male youth.

    PubMed

    Savin-Williams, Ritch C; Ream, Geoffrey L

    2003-12-01

    The purpose of this study was to provide data addressing Diamond's (this issue) 4 problem areas in sexual orientation research by comparing gay, bisexual, and questioning male youth who report attempting suicide with those who do not. Secondary analyses were conducted with 2 datasets, 1 with a gay support group (n = 51) and the other with online youth (n = 681). Reported suicide attempts ranged from 39% among support-group youth, to 25% among Internet gay support group youth, to 9% among Internet non-support group youth. Sexual orientation, behavior, and identity did not predict suicidal attempt status, but suicide attempters experienced higher levels of both generic life stressors (low self-esteem, substance use, victimization) and gay-related stressors, particularly those directly related to visible (femininity) and behavioral (gay sex) aspects of their sexual identity. Support-group attendance was related to higher levels of suicidality and life stressors, as well as certain resiliency factors. Results suggest that there exists a minority of sexual-minority youth who are at risk but that it would be inappropriate to characterize the entire population as such.

  12. 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.

  13. Changes in the sexual orientation of six heterosexual male-to-female transsexuals.

    PubMed

    Daskalos, C T

    1998-12-01

    Researchers traditionally have assumed that sex reassignment procedures do not change sexual orientation. Of 20 transsexuals of various types that were interviewed, 6 heterosexual male-to-female transsexual respondents reported that their sexual orientation had changed since transitioning from male to female. These respondents stated that before transitioning they had been sexually orientated towards females. After transitioning, these same respondents reported that they were sexually orientated towards males. Five of the six respondents reported having various sexual encounters with males since transitioning. The respondents explained the changes in their sexual orientation as part of their emerging female gender identities. Three of the respondents claimed that the use of female hormones played a role in changing their sexual orientation. It did not appear that the respondents' post-transitional sexual attractions towards males were similar to autogynephilic images and fantasies described by Blanchard (1991).

  14. Changes in blood testosterone concentrations after surgical and chemical sterilization of male free-roaming dogs in southern Chile.

    PubMed

    Vanderstichel, R; Forzán, M J; Pérez, G E; Serpell, J A; Garde, E

    2015-04-01

    There is a growing interest in chemical sterilization as an alternative to surgical castration in large-scale sterilization campaigns to control canine populations. An important step toward understanding the short-term and long-term effects of chemical sterilants is to determine their impact on blood testosterone concentrations, particularly as these could influence dog behavior after treatment. A field trial was conducted with 118 free-roaming male dogs in the Chilean Patagonia, where 36 dogs were chemically sterilized using EsterilSol, 39 dogs were surgically castrated, and 43 dogs remained intact as controls. Blood testosterone levels were determined at four time periods: on enrollment 6 months before treatment (t-6m), at the time of treatment (t0, within one hour after surgical castration or chemical sterilization and during a concurrent 2-week period for the control group), four (t+4m), and six (t+6m) months after treatment. Intrinsic and temporal factors were evaluated; age was significantly associated with testosterone, where dogs 2- to 4-year-old had the highest testosterone concentrations (P = 0.036), whereas body weight and body condition scores were not associated with testosterone; testosterone concentration was not influenced by time of day, month, or season. After treatment (t+4m and t+6m), all of the surgically castrated dogs had testosterone concentrations below 1.0 ng/mL. On the basis of this cut point (<1 ng/mL), testosterone remained unchanged in 66% of the chemically sterilized dogs at both t+4m and t+6m; it remained low for 22% of dogs at both t+4m and t+6m; it was unchanged at t+4m but low at t+6m in 9% of dogs; and, it was low at t+4m but reverted back to unchanged at t+6m in one dog (3%). Incidentally, testosterone in chemically sterilized dogs increased dramatically within 1 hour of treatment (t0), more than doubling (131%) the concentration of control dogs at the time of treatment (t0), likely because of severe necrosis of

  15. Monitoring gene flow from transgenic sugar beet using cytoplasmic male-sterile bait plants.

    PubMed

    Saeglitz, C; Pohl, M; Bartsch, D

    2000-12-01

    One of the most discussed environmental effects associated with the use of transgenic plants is the flow of genes to plants in the environment. The flow of genes may occur through pollen since it is the reproductive system that is designed for gene movement. Pollen-mediated gene escape is hard to control in mating plants. Pollen from a wind pollinator can move over distances of more than 1000 m. To investigate the efficiency of transgenic pollen movement under realistic environmental conditions, the use of bait plants might be an effective tool. In this study, cytoplasmic male-sterile (CMS) sugar beets were tested with regard to their potential for monitoring transgene flow. As the pollen source, transgenic sugar beets were used that express recombinant DNA encoding viral (beet necrotic yellow vein virus) resistance, and antibiotic (kanamycin) and herbicide (glufosinate) tolerance genes. In a field trial, the effectiveness of a hemp (Cannabis sativa) stripe containment strategy was tested by measuring the frequency of pollinated CMS bait plants placed at different distances and directions from a transgenic pollen source. The results demonstrated the ineffectiveness of the containment strategy. Physiological and molecular tests confirmed the escape and production of transgenic offspring more than 200 m behind the hemp containment. Since absolute containment is unlikely to be effective, the CMS-bait plant detection system is a useful tool for other monitoring purposes.

  16. MALE STERILITY1 Is Required for Tapetal Development and Pollen Wall Biosynthesis[W][OA

    PubMed Central

    Yang, Caiyun; Vizcay-Barrena, Gema; Conner, Katie; Wilson, Zoe A.

    2007-01-01

    The Arabidopsis thaliana MALE STERILITY1 (MS1) gene is critical for viable pollen formation and has homology to the PHD-finger class of transcription factors; however, its role in pollen development has not been fully defined. We show that MS1 transcription appears to be autoregulated by the wild-type MS1 transcript or protein. Using a functional green fluorescent protein (GFP) fusion to analyze the temporal and spatial expression of MS1, we demonstrate that the MS1:GFP protein is nuclear localized within the tapetum and is expressed in a developmentally regulated manner between late tetraspore and microspore release, then rapidly breaks down, probably by ubiquitin-dependent proteolysis. Absence of MS1 expression results in changes in tapetal secretion and exine structure. Microarray analysis has shown that 260 (228 downregulated and 32 upreglated) genes have altered expression in young ms1 buds. These genes are primarily associated with pollen wall and coat formation; however, a number of transcription factors and Cys proteases have also been identified as the putative primary regulatory targets of MS1. Ectopic expression of MS1 alters transcriptional regulation of vegetative gene expression, resulting in stunted plants with increased levels of branching, partially fertile flowers and an apparent increase in wall material on mature pollen. MS1 therefore plays a critical role in the induction of pollen wall and pollen coat materials in the tapetum and, ultimately, the production of viable pollen. PMID:18032629

  17. 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.

  18. Open Field Release of Genetically Engineered Sterile Male Aedes aegypti in Malaysia

    PubMed Central

    Raduan, Norzahira; Kwee Wee, Lim; Hong Ming, Wong; Guat Ney, Teoh; Rahidah A.A., Siti; Salman, Sawaluddin; Subramaniam, Selvi; Nordin, Oreenaiza; Hanum A.T., Norhaida; Angamuthu, Chandru; Marlina Mansor, Suria; Lees, Rosemary S.; Naish, Neil; Scaife, Sarah; Gray, Pam; Labbé, Geneviève; Beech, Camilla; Nimmo, Derric; Alphey, Luke; Vasan, Seshadri S.; Han Lim, Lee; Wasi A., Nazni; Murad, Shahnaz

    2012-01-01

    Background Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. Methodology/Principal Findings Adult male mosquitoes were released into an uninhabited forested area of Pahang, Malaysia. Their survival and dispersal was assessed by use of a network of traps. Two strains were used, an engineered ‘genetically sterile’ (OX513A) and a wild-type laboratory strain, to give both absolute and relative data about the performance of the modified mosquitoes. The two strains had similar maximum dispersal distances (220 m), but mean distance travelled of the OX513A strain was lower (52 vs. 100 m). Life expectancy was similar (2.0 vs. 2.2 days). Recapture rates were high for both strains, possibly because of the uninhabited nature of the site. Conclusions/Significance After extensive contained studies and regulatory scrutiny, a field release of engineered mosquitoes was safely and successfully conducted in Malaysia. The engineered strain showed similar field longevity to an unmodified counterpart, though in this setting dispersal was reduced relative to the unmodified strain. These data are encouraging for the future testing and implementation of genetic control strategies and will help guide future field use of this and other engineered strains. PMID:22970102

  19. Increased vulnerability of hippocampal CA1 neurons to hypoperfusion in ataxia and male sterility (AMS) mouse.

    PubMed

    Liang, Xueyun; Nagai, Atsushi; Sheikh, Abdullah Md; Wang, Hui; Mitaki, Shingo; Araki, Asuka; Maruyama, Riruke; Harada, Takayuki

    2013-02-04

    The nna1 gene mutation is associated with spontaneous degeneration of cerebellar Purkinje cells and germ cells in Ataxia and Male Sterility (AMS) mouse. Since nna1 is also expressed in hippocampal neurons, we investigated their vulnerability to hypoperfusion in AMS mouse. Eight-week-old male wild type (WT) and AMS mice were subjected to bilateral common carotid artery occlusion (BCCAO) for 10 min and sacrificed 1, 3, 7 and 28 days after BCCAO. Nissl staining revealed the neuronal cell loss and pyknotic change in the CA1 of AMS mice. TUNEL(+) apoptotic cells were found in the area at 7 days in AMS mice. Bcl-2 mRNA and protein in WT hippocampus were increased, while they were not increased in AMS. Bax mRNA was increased in AMS. Moreover, Bax activation was immunohistochemically demonstrated only in AMS at 3 and 7 days after BCCAO. An oxidative DNA damage marker, 8-hydroxydeoxyguanosine-positive cells were increased in both strains at 1 day; decreased in WT at 3 days but remained high in AMS. BCCAO increased glutathione, an antioxidant, in WT, but not in AMS at 3 days. The mRNA level of mitochondrial uncoupling protein 2, a regulator of oxidative stress, was increased only in WT at 1 day. Nna1 mRNA was similarly expressed in WT and AMS, but the protein was undetectable in AMS. Thus, our results indicate the increased vulnerability of hippocampal CA1 neurons of AMS mice to cerebral hypoperfusion could be due to an imbalance between oxidative stress and antioxidative defense system.

  20. The effect of the radio-protective agents ethanol, trimethylglycine, and beer on survival of X-ray-sterilized male Aedes aegypti

    PubMed Central

    2013-01-01

    Background Sterile Insect Technique (SIT) has been successfully implemented to control, and in some cases, eradicate, dipteran insect populations. SIT has great potential as a mosquito control method. Different sterilization methods have been used on mosquitoes ranging from chemosterilization to genetically modified sterile male mosquito strains; however, sterilization with ionizing radiation is the method of choice for effective sterilization of male insects for most species. The lack of gentle radiation methods has resulted in significant complications when SIT has been applied to mosquitoes. Several studies report that irradiating mosquitoes resulted in a decrease in longevity and mating success compared to unirradiated males. The present study explored new protocols for mosquito sterilization with ionizing radiation that minimized detrimental effects on the longevity of irradiated males. Methods We tested three compounds that have been shown to act as radioprotectors in the mouse model system - ethanol, trimethylglycine, and beer. Male Aedes aegypti were treated with one of three chosen potential radioprotectors and were subsequently irradiated with identical doses of long-wavelength X-rays. We evaluated the effect of these radioprotectors on the longevity of male mosquito after irradiation. Results We found that X-ray irradiation with an absorbed dose of 1.17 gy confers complete sterility. Irradiation with this dose significantly shortened the lifespan of male mosquitoes and all three radioprotectors tested significantly enhanced the lifespan of irradiated mosquito males. Conclusion Our results suggest that treatment with ethanol, beer, or trimethylglycine before irradiation can be used to enhance longevity in mosquitoes. PMID:23866939

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

    ERIC Educational Resources Information Center

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

    2007-01-01

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

  2. 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.

  3. Copulation is reactivated by bromocriptine in male rats after reaching sexual satiety with a same sexual mate.

    PubMed

    Rojas-Hernández, Jorge; Juárez, Jorge

    2015-11-01

    Male sexual satiety has been associated with a decrease in dopamine levels. Spontaneous recovery of copulatory behavior begins at least 72 h after sexual satiety is reached or in the condition in which a sexually-satiated male is exposed to a new receptive female distinct from the one with which sexual satiety was reached. The aim of the present study was to explore whether dopaminergic activation by bromocriptine (BrCr) can reactivate copulatory behavior with the same sexual mate immediately after sexual satiety is reached. Male rats were divided into three groups exposed to one of the following three conditions: 1) administration of 2 mg/kgs.c. of BrCr and exposure to the same female with whom sexual satiety was previously reached; 2) administration of 0.3 mLs.c. of the vehicle solution with exposure to the same female with whom sexual satiety was reached; and, 3) exposure to a new receptive female after sexual satiety was reached. Results showed that BrCr significantly reactivated copulatory capability in sexually-satiated males with the same receptive female. In contrast, no males in the vehicle group ejaculated with the same female after reaching sexual exhaustion. Copulation was reactivated by BrCr in a way similar to that observed in untreated males exposed to a new receptive female (i.e., the Coolidge effect). The reversal of sexual satiety in the males treated with BrCr could be explained by its action on D2 family receptors, which promotes a reactivation of sexual motivation at a level sufficient to allow renewed copulation with the same female mate.

  4. Pre- and postcopulatory sexual selection favor aggressive, young males in polyandrous groups of red junglefowl.

    PubMed

    McDonald, Grant C; Spurgin, Lewis G; Fairfield, Eleanor A; Richardson, David S; Pizzari, Tommaso

    2017-03-28

    A challenge in evolutionary biology is to understand the operation of sexual selection on males in polyandrous groups, where sexual selection occurs before and after mating. Here, we combine fine-grained behavioural information (>41,000 interactions) with molecular parentage data to study sexual selection in replicated, age-structured groups of polyandrous red junglefowl, Gallus gallus. Male reproductive success was determined by the number of females mated (precopulatory sexual selection) and his paternity share, which was driven by the polyandry of his female partners (postcopulatory sexual selection). Pre- and postcopulatory components of male reproductive success covaried positively; males with high mating success also had high paternity share. Two male phenotypes affected male pre- and postcopulatory performance: average aggressiveness towards rival males and age. Aggressive males mated with more females and more often with individual females, resulting in higher sexual exclusivity. Younger males mated with more females and more often with individual females, suffering less intense sperm competition than older males. Older males had a lower paternity share even allowing for their limited sexual exclusivity, indicating they may produce less competitive ejaculates. These results indicate that - in these populations - postcopulatory sexual selection reinforces precopulatory sexual selection, consistently promoting younger and more aggressive males. This article is protected by copyright. All rights reserved.

  5. Transcriptome Sequencing Analyses between the Cytoplasmic Male Sterile Line and Its Maintainer Line in Welsh Onion (Allium fistulosum L.)

    PubMed Central

    Liu, Qianchun; Lan, Yanping; Wen, Changlong; Zhao, Hong; Wang, Jian; Wang, Yongqin

    2016-01-01

    Cytoplasmic male sterility (CMS) is important for exploiting heterosis in crop plants and also serves as a model for investigating nuclear–cytoplasmic interaction. The molecular mechanism of cytoplasmic male sterility and fertility restoration was investigated in several important economic crops but remains poorly understood in the Welsh onion. Therefore, we compared the differences between the CMS line 64-2 and its maintainer line 64-1 using transcriptome sequencing with the aim of determining critical genes and pathways associated with male sterility. This study combined two years of RNA-seq data; there were 1504 unigenes (in May 2013) and 2928 unigenes (in May 2014) that were differentially expressed between the CMS and cytoplasmic male maintainer Welsh onion varieties. Known CMS-related genes were found in the set of differentially expressed genes and checked by qPCR. These genes included F-type ATPase, NADH dehydrogenase, cytochrome c oxidase, etc. Overall, this study demonstrated that the CMS regulatory genes and pathways may be associated with the mitochondria and nucleus in the Welsh onion. We believe that this transcriptome dataset will accelerate the research on CMS gene clones and other functional genomics research on A. fistulosum L. PMID:27376286

  6. A randomized, controlled, multicenter contraceptive efficacy clinical trial of the intravas device, a nonocclusive surgical male sterilization

    PubMed Central

    Lu, Wen-Hong; Liang, Xiao-Wei; Gu, Yi-Qun; Wu, Wei-Xiong; Bo, Li-Wei; Zheng, Tian-Gui; Chen, Zhen-Wen

    2014-01-01

    Because of unavoidable complications of vasectomy, this study was undertaken to assess the efficacy and safety of male sterilization with a nonobstructive intravas device (IVD) implanted into the vas lumen by a mini-surgical method compared with no-scalpel vasectomy (NSV). IVDs were categorized into two types: IVD-B has a tail used for fixing to the vas deferens (fixed wing) whereas IVD-A does not. A multicenter prospective randomized controlled clinical trial was conducted in China. The study was comprised of 1459 male volunteers seeking vasectomy who were randomly assigned to the IVD-A (n = 487), IVD-B (n = 485) or NSV (n = 487) groups and underwent operation. Follow-up included visits at the 3rd–6th and 12th postoperative months. The assessments of the subjects involved regular physical examinations (including general and andrological examinations) and semen analysis. The subjects’ partners also underwent monitoring for pregnancy by monthly interviews regarding menstruation and if necessary, urine tests. There were no significant differences in pregnancy rates (0.65% for IVD-A, 0 for IVD-B and 0.21% for NSV) among the three groups (P > 0.05). The cumulative rates of complications at the 12th postoperative month were zero, 0.9% and 1.7% in the three groups, respectively. In conclusion, IVD male sterilization exhibits a low risk of long-term adverse events and was found to be effective as a male sterilization method, similar to the NSV technique. IVD male sterilization is expected to be a novel contraceptive method. PMID:24589454

  7. Sexual experience affects reproductive behavior and preoptic androgen receptors in male mice

    PubMed Central

    Swaney, William T.; Dubose, Brittany N.; Curley, James P.; Champagne, Frances A.

    2012-01-01

    Reproductive behavior in male rodents is made up of anticipatory and consummatory elements which are regulated in the brain by sensory systems, reward circuits and hormone signaling. Gonadal steroids play a key role in the regulation of male sexual behavior via steroid receptors in the hypothalamus and preoptic area. Typical patterns of male reproductive behavior have been characterized, however these are not fixed but are modulated by adult experience. We assessed the effects of repeated sexual experience on male reproductive behavior of C57BL/6 mice; including measures of olfactory investigation of females, mounting, intromission and ejaculation. The effects of sexual experience on the number of cells expressing either androgen receptor (AR) or estrogen receptor alpha (ERα) in the primary brain nuclei regulating male sexual behavior was also measured. Sexually experienced male mice engaged in less sniffing of females before initiating sexual behavior and exhibited shorter latencies to mount and intromit, increased frequency of intromission, and increased duration of intromission relative to mounting. No changes in numbers of ERα-positive cells were observed, however sexually experienced males had increased numbers of AR-positive cells in the medial preoptic area (MPOA); the primary regulatory nucleus for male sexual behavior. These results indicate that sexual experience results in a qualitative change in male reproductive behavior in mice that is associated with increased testosterone sensitivity in the MPOA and that this nucleus may play a key integrative role in mediating the effects of sexual experience on male behavior. PMID:22266118

  8. Differences between males and females in motives for engaging in sexual intercourse.

    PubMed

    Carroll, J L; Volk, K D; Hyde, J S

    1985-04-01

    In a test of the hypothesis that a difference exists between males and females in motives for participating in sexual intercourse, a random sample of 249 college students was given a questionnaire containing questions about sexual behavior and attitudes, focusing on motives for having intercourse. There were significant differences between males and females in approval of casual sexual intercourse, number of premarital sexual partners, most important part of sexual behavior, and whether an emotional involvement was a prerequisite for participating in sexual intercourse. Effect-size analyses indicated that these differences are large, with a median omega 2 = 0.24. Both males and females approved of premarital sexual intercourse in a serious relationship and stressed the importance of feeling loved and needed. However, males found it easier to participate in sexual intercourse without an emotional commitment, whereas females were unlikely to want intercourse for physical pleasure in the absence of psychological involvement.

  9. Colonization of a hybrid strain to restore male Anastrepha ludens (Diptera: Tephritidae) mating competitiveness for sterile insect technique programs.

    PubMed

    Rull, Juan; Barreda-Landa, Abraham

    2007-06-01

    To restore male mating competitiveness of Mexican fruit flies, Anastrepha ludens (Loew) (Diptera: Tephritidae), reared for sterile insect releases by the Mexican Fruit fly Eradication Campaign, two strain replacement techniques were evaluated. Field cage male competitiveness tests revealed that laboratory males of the Metapa strain mated 3 times less often with wild females than field-collected wild males. A strain developed from the cross of wild males and laboratory females (hybrid strain) was similar to a strain developed from the cross of laboratory males and females (laboratory strain) in that its females produced similar amounts of eggs and the eggs displayed similar levels of hatch and egg-to-pupa transformation in artificial diet. By contrast, a strain developed from the cross of wild males and females (wild strain), forced into artificial rearing, experienced a series of bottlenecks involving reduced egg laying and extremely poor development in diet. The male F1 progeny of the hybrid strain and field-collected wild males outcompeted Fl laboratory males in field cage tests for matings with field-collected wild females. In conclusion, we found that strains developed from the cross of wild males and laboratory females allowed us to restore male mating competitiveness of F1 Mexican fruit flies without compromising mass-rearing production.

  10. A new role for GABAergic transmission in the control of male rat sexual behavior expression.

    PubMed

    Rodríguez-Manzo, Gabriela; Canseco-Alba, Ana

    2017-03-01

    GABAergic transmission in the ventral tegmental area (VTA) exerts a tonic inhibitory influence on mesolimbic dopaminergic neurons' activity. Blockade of VTA GABAA receptors increases dopamine release in the nucleus accumbens (NAcc). Increases in NAcc dopamine levels typically accompany sexual behavior display. Copulation to satiety is characterized by the instatement of a long lasting (72h) sexual behavior inhibition and the mesolimbic system appears to be involved in this phenomenon. GABAergic transmission in the VTA might play a role in the maintenance of this long lasting sexual inhibitory state. To test this hypothesis, in the present work we investigated the effect of GABAA receptor blockade in sexually exhausted males 24h after copulation to satiety, once the sexual inhibitory state is established, and compared it with its effect in sexually experienced rats. Results showed that low doses of systemically administered bicuculline induced sexual behavior expression in sexually exhausted rats, but lacked an effect on copulation of sexually experienced animals. Intra-VTA bilateral infusion of bicuculline did not modify sexual behavior of sexually experienced rats, but induced sexual behavior expression in all the sexually exhausted males. Hence, GABA plays a role in the control of sexual behavior expression at the VTA. The role played by GABAergic transmission in male sexual behavior expression of animals with distinct sexual behavior conditions is discussed.

  11. Characterizing and marker-assisting a novel chili pepper (Capsicum annuum L.) yellow bud mutant with cytoplasmic male sterility.

    PubMed

    Sun, G S; Dai, Z L; Bosland, P W; Wang, Q; Sun, C Q; Zhang, Z C; Ma, Z H

    2017-02-23

    Cytoplasmic male sterility (CMS) in pepper is a better way to produce hybrid seeds compared to manual production. We used the two sequence characterized amplified region (SCAR) markers (CRF-SCAR and CMS-SCAR130) in CMS pepper, to identify the genotype. We assembled two CMS yellow bud mutants (YBM; YBM12-A and YBM12-B). This mutation in leaf color is controlled by a single dominant nuclear gene. The aim was to create a new hybrid seed production method that reduces the costs and increases F1 hybrid seed purity. The results suggest that the CRF-SCAR and CMS-SCAR130 markers can be used together in multiple generations to screen for restorer or maintainer genes. We found the marker linked to the restorer gene (Rf) in the C-line and F1 hybrids, as well as partially in the F2 generation, whereas it was not found in the sterile YBM12-A or the maintainer line YBM12-B. In the F2 population, sterility and fertility segregated at a 3:1 ratio based on the CRF-SCAR marker. A 130 bp fragment was produced in the YBM12-A, F1, and F2 populations, suggesting that these lines contained sterile cytoplasm. A 140 bp fragment present in the YBM12-B and C-line indicated that these lines contained normal cytoplasm. In addition, we identified some morphological characters distinguishing sterile and fertile buds and flowers that may be linked to the sterility gene. If more restorer lines are identified, CMS expressing the YBM trait can be used in hybrid seed production.

  12. Cytoplasmic Male Sterility-Associated Chimeric Open Reading Frames Identified by Mitochondrial Genome Sequencing of Four Cajanus Genotypes

    PubMed Central

    Tuteja, Reetu; Saxena, Rachit K.; Davila, Jaime; Shah, Trushar; Chen, Wenbin; Xiao, Yong-Li; Fan, Guangyi; Saxena, K. B.; Alverson, Andrew J.; Spillane, Charles; Town, Christopher; Varshney, Rajeev K.

    2013-01-01

    The hybrid pigeonpea (Cajanus cajan) breeding technology based on cytoplasmic male sterility (CMS) is currently unique among legumes and displays major potential for yield increase. CMS is defined as a condition in which a plant is unable to produce functional pollen grains. The novel chimeric open reading frames (ORFs) produced as a results of mitochondrial genome rearrangements are considered to be the main cause of CMS. To identify these CMS-related ORFs in pigeonpea, we sequenced the mitochondrial genomes of three C. cajan lines (the male-sterile line ICPA 2039, the maintainer line ICPB 2039, and the hybrid line ICPH 2433) and of the wild relative (Cajanus cajanifolius ICPW 29). A single, circular-mapping molecule of length 545.7 kb was assembled and annotated for the ICPA 2039 line. Sequence annotation predicted 51 genes, including 34 protein-coding and 17 RNA genes. Comparison of the mitochondrial genomes from different Cajanus genotypes identified 31 ORFs, which differ between lines within which CMS is present or absent. Among these chimeric ORFs, 13 were identified by comparison of the related male-sterile and maintainer lines. These ORFs display features that are known to trigger CMS in other plant species and to represent the most promising candidates for CMS-related mitochondrial rearrangements in pigeonpea. PMID:23792890

  13. Reversible male sterility in eggplant (Solanum melongena L.) by artificial microRNA-mediated silencing of general transcription factor genes.

    PubMed

    Toppino, Laura; Kooiker, Maarten; Lindner, Matias; Dreni, Ludovico; Rotino, Giuseppe L; Kater, Martin M

    2011-08-01

    Since decades, plant male sterility is considered a powerful tool for biological containment to minimize unwanted self-pollination for hybrid seed production. Furthermore, prevention of pollen dispersal also answers to concerns regarding transgene flow via pollen from Genetically Modified (GM) crops to traditional crop fields or wild relatives. We induced male sterility by suppressing endogenous general transcription factor genes, TAFs, using anther-specific promoters combined with artificial microRNA (amiRNA) technology (Schwab et al., 2006). The system was made reversible by the ethanol inducible expression of an amiRNA-insensitive form of the target gene. We provide proof of concept in eggplant, a cultivated crop belonging to the Solanaceae family that includes many important food crops. The transgenic eggplants that we generated are completely male sterile and fertility can be fully restored by short treatments with ethanol, confirming the efficiency but also the reliability of the system in view of open field cultivation. By combining this system with induced parthenocarpy (Rotino et al., 1997), we provide a novel example of complete transgene containment in eggplant, which enables biological mitigation measures for the benefit of coexistence or biosafety purposes for GM crop cultivation.

  14. Correlates of negative attitudes toward gay men: sexism, male role norms, and male sexuality.

    PubMed

    Davies, Michelle

    2004-08-01

    Research has shown that heterosexual men are more negative toward gay men than women are on measures of attitudes toward homosexual behaviour and homosexual persons (Kite & Whitley, 1996). Gender differences in attitudes toward gay men's civil rights are less clear. No empirical studies, however, have investigated these findings with a scale that measures specifically these three attitudinal subcomponents. This study was a preliminary test of a scale that measured these subcomponents. In addition, this study investigated the relationship between these subcomponents and other attitudinal measures: hostile sexism, male toughness, and attitudes toward male sexuality. Results revealed that attitudes toward homosexual behaviour and homosexual persons comprised one factor: affective reactions toward gay men. Results showed that men were more negative on affective reactions than women were. No gender differences were revealed on attitudes toward civil rights. I found significant correlations between affective reactions, hostile sexism, male toughness, and male sexuality. I discuss these findings in relation to traditional gender role beliefs and make suggestions for future research.

  15. Male Escorts' and Male Clients' Sexual Behavior During Their Last Commercial Sexual Encounter: Comparing and Contrasting Findings from Two Online Studies.

    PubMed

    Grov, Christian; Rodríguez-Díaz, Carlos E; Jovet-Toledo, Gerardo G

    2016-05-01

    Much of what is known about commercial sexual encounters between men is based on data gathered from escorts. With few exceptions, studies have not compared male clients' reports of behavior during commercial sexual encounters with male escorts'. The present study draws from two datasets, a 2012 survey of clients (n = 495) and a 2013 survey of escorts (n = 387)--both used virtually identical measures of sexual behavior during the most recent commercial sexual encounter. For clients and escorts, the majority eschewed having sex without a condom, and kissing and oral sex were among the most common behaviors reported. Using logistic regression, both samples were compared across 15 sexual behaviors, finding significant differences in six--the escort sample had greater odds of reporting their last commercial sexual encounter involved watching the client masturbate, viewing porn, role play (dad/son, dominant/submissive), and having prior sexual experience with their commercial partner. The escort sample had lower odds of reporting that the client watched the escort masturbate, and being told partner's HIV status. In multivariable modeling, both samples did not significantly differ in reports of condomless anal sex. Male-male commercial sexual encounters appear to be involved in a wide range of sexual behaviors, many of which convey low-to-no risk of HIV transmission.

  16. Organelle Simple Sequence Repeat Markers Help to Distinguish Carpelloid Stamen and Normal Cytoplasmic Male Sterile Sources in Broccoli

    PubMed Central

    Shu, Jinshuai; Liu, Yumei; Li, Zhansheng; Zhang, Lili; Fang, Zhiyuan; Yang, Limei; Zhuang, Mu; Zhang, Yangyong; Lv, Honghao

    2015-01-01

    We previously discovered carpelloid stamens when breeding cytoplasmic male sterile lines in broccoli (Brassica oleracea var. italica). In this study, hybrids and multiple backcrosses were produced from different cytoplasmic male sterile carpelloid stamen sources and maintainer lines. Carpelloid stamens caused dysplasia of the flower structure and led to hooked or coiled siliques with poor seed setting, which were inherited in a maternal fashion. Using four distinct carpelloid stamens and twelve distinct normal stamens from cytoplasmic male sterile sources and one maintainer, we used 21 mitochondrial simple sequence repeat (mtSSR) primers and 32 chloroplast SSR primers to identify a mitochondrial marker, mtSSR2, that can differentiate between the cytoplasm of carpelloid and normal stamens. Thereafter, mtSSR2 was used to identify another 34 broccoli accessions, with an accuracy rate of 100%. Analysis of the polymorphic sequences revealed that the mtSSR2 open reading frame of carpelloid stamen sterile sources had a deletion of 51 bases (encoding 18 amino acids) compared with normal stamen materials. The open reading frame is located in the coding region of orf125 and orf108 of the mitochondrial genomes in Brassica crops and had the highest similarity with Raphanus sativus and Brassica carinata. The current study has not only identified a useful molecular marker to detect the cytoplasm of carpelloid stamens during broccoli breeding, but it also provides evidence that the mitochondrial genome is maternally inherited and provides a basis for studying the effect of the cytoplasm on flower organ development in plants. PMID:26407159

  17. Energetic constraints on sexual activity in the male edible dormouse (Glis glis).

    PubMed

    Fietz, Joanna; Schlund, W; Dausmann, K H; Regelmann, M; Heldmaier, G

    2004-01-01

    The aim of this study was to examine to what extent reproductive activity in male edible dormice (Glis glis) might be energetically constrained. Demographic data, morphometric data, and oral body temperature (T(or)) measurements were collected in two study areas between 1993 and 2002 in southwest Germany and combined with subcutaneous body temperature (T(sc)) registrations of captive dormice. T(sc) measurements were collected directly after emergence from hibernation (June) until the end of the mating season (July). Wild edible dormice showed strong fluctuations in their reproductive output between years. Not all males were sexually active each year and the number of litters born was positively correlated with the number of sexually active males, which suggests that sexual activity in males is constrained and in turn limits reproductive success. A comparison of the T(or) of sexually quiescent and active males revealed that sexually quiescent males had significantly lower T(or) (median: 28.8 degrees C; 25/75% quartiles: 16.4/31.0; n=31) than sexually active males (median: 34.2 degrees C; 25/75% quartiles: 32.0/35.6; n=156). Body condition of sexually active and quiescent males was not different after emergence from hibernation. However, sexually active males showed a significant reduction in their body condition between June and July, the time of mating, while body condition of sexually quiescent males remained constant. Continuous T(sc) registrations in captive sexually active male dormice showed strong circadian T(sc) fluctuations. Even though daily torpor bouts with T(sc) below 20 degrees C occurred in these males, most of the time T(sc) fluctuated above 30 degrees C, which is known as the critical body temperature threshold above which testes maturation can take place in this species. These results demonstrate that male dormice incur high costs due to sexual activity and that thermoregulation is determined by a trade-off between energetic savings and

  18. Prevalence and denial of sexual abuse in a male psychiatric inpatient population.

    PubMed

    Lab, Damon D; Moore, Estelle

    2005-08-01

    While the link between sexual abuse and psychiatric morbidity is well established, there are only a few studies that have investigated the prevalence of sexual abuse in male psychiatric populations and these studies have typically employed designs that ignore methodological issues specific to male sexual abuse. The present study aims to contribute to this research using as methodologically sound approach as possible. Seventy-four male inpatients were interviewed using a questionnaire (J. N. Briere, 1992) about childhood sexual experiences. Approximately one third reported incidents that met this study's criteria for sexual abuse. Many of these men did not label such experiences as "sexual abuse." The results suggest that mental health professionals need to be aware that many of their male patients may have a history of sexual abuse and that potential minimization or denial of it is a barrier to disclosure.

  19. Sexual Excitability and Dysfunctional Coping Determine Cybersex Addiction in Homosexual Males.

    PubMed

    Laier, Christian; Pekal, Jaro; Brand, Matthias

    2015-10-01

    Cybersex addiction (CA) has been mostly investigated in heterosexual males. Recent findings have demonstrated an association between CA severity and indicators of sexual excitability, and that coping by sexual behaviors mediated the relationship between sexual excitability and CA symptoms. The aim of this study was to test this mediation in a sample of homosexual males. Seventy-one homosexual males were surveyed online. Questionnaires assessed symptoms of CA, sensitivity to sexual excitation, pornography use motivation, problematic sexual behavior, psychological symptoms, and sexual behaviors in real life and online. Moreover, participants viewed pornographic videos and indicated their sexual arousal before and after the video presentation. Results showed strong correlations between CA symptoms and indicators of sexual arousal and sexual excitability, coping by sexual behaviors, and psychological symptoms. CA was not associated with offline sexual behaviors and weekly cybersex use time. Coping by sexual behaviors partially mediated the relationship between sexual excitability and CA. The results are comparable with those reported for heterosexual males and females in previous studies and are discussed against the background of theoretical assumptions of CA, which highlight the role of positive and negative reinforcement due to cybersex use.

  20. Sexual interactions with unfamiliar females reduce hippocampal neurogenesis among adult male rats.

    PubMed

    Spritzer, M D; Curtis, M G; DeLoach, J P; Maher, J; Shulman, L M

    2016-03-24

    Recent experiments have shown that sexual interactions prior to cell proliferation cause an increase in neurogenesis in adult male rats. Because adult neurogenesis is critical for some forms of memory, we hypothesized that sexually induced changes in neurogenesis may be involved in mate recognition. Sexually naive adult male rats were either exposed repeatedly to the same sexual partner (familiar group) or to a series of novel sexual partners (unfamiliar group), while control males never engaged in sexual interactions. Ovariectomized female rats were induced into estrus every four days. Males were given two injections of 5-bromo-2'-deoxyuridine (BrdU) (200mg/kg) to label proliferating cells, and the first sexual interactions occurred three days later. Males in the familiar and unfamiliar groups engaged in four, 30-min sexual interactions at four-day intervals, and brain tissue was collected the day after the last sexual interaction. Immunohistochemistry followed by microscopy was used to quantify BrdU-labeled cells. Sexual interactions with unfamiliar females caused a significant reduction in neurogenesis in the dentate gyrus compared to males that interacted with familiar females and compared to the control group. The familiar group showed no difference in neurogenesis compared to the control group. Males in the familiar group engaged in significantly more sexual behavior (ejaculations and intromissions) than did males in the unfamiliar group, suggesting that level of sexual activity may influence neurogenesis levels. In a second experiment, we tested whether this effect was unique to sexual interactions by replicating the entire procedure using anestrus females. We found that interactions with unfamiliar anestrus females reduced neurogenesis relative to the other groups, but this effect was not statistically significant. In combination, these results indicate that interactions with unfamiliar females reduce adult neurogenesis and the effect is stronger for sexual

  1. 7α-Hydroxypregnenolone regulates diurnal changes in sexual behavior of male quail.

    PubMed

    Ogura, Yuki; Haraguchi, Shogo; Nagino, Koki; Ishikawa, Kei; Fukahori, Yoko; Tsutsui, Kazuyoshi

    2016-02-01

    In the Japanese quail, 7α-hydroxypregnenolone, a previously undescribed avian neurosteroid, is actively produced in the brain. 7α-Hydroxypregnenolone acts as a novel neuronal activator to stimulate locomotor activity of quail. Therefore, in this study, we determined whether 7α-hydroxypregnenolone changes the expression of sexual behavior in Japanese quail. We first measured diurnal changes in sexual behavior of male quail exposed to a long-day photoperiod. We found that sexual behavior of male quail was high in the morning when endogenous 7α-hydroxypregnenolone level is high. Subsequently, we centrally administered 7α-hydroxypregnenolone in the evening when endogenous 7α-hydroxypregnenolone level is low. In the 30 min after intracerebroventricular (ICV) injection, 7α-hydroxypregnenolone dose dependently increased the frequency of sexual behavior of male quail. However, 7β-hydroxypregnenolone, a stereoisomer of 7α-hydroxypregnenolone, did not effect on the frequency of sexual behavior of male quail. In addition, to confirm the action of 7α-hydroxypregnenolone on sexual behavior, male birds received an ICV injection of ketoconazole, an inhibitor of cytochrome P450s, and behavioral experiments were performed in the morning. Ketoconazole significantly decreased the frequency of sexual behavior of male quail, whereas administration of 7α-hydroxypregnenolone to ketoconazole-treated males increased the frequency of their sexual behavior. These results indicate that 7α-hydroxypregnenolone regulates diurnal changes in sexual behavior of male quail.

  2. Inheritance of steroid-independent male sexual behavior in male offspring of B6D2F1 mice.

    PubMed

    McInnis, Christine M; Bonthuis, Paul J; Rissman, Emilie F; Park, Jin Ho

    2016-04-01

    The importance of gonadal steroids in modulating male sexual behavior is well established. Individual differences in male sexual behavior, independent of gonadal steroids, are prevalent across a wide range of species, including man. However, the genetic mechanisms underlying steroid-independent male sexual behavior are poorly understood. A high proportion of B6D2F1 hybrid male mice demonstrates steroid-independent male sexual behavior (identified as "maters"), providing a mouse model that opens up avenues of investigation into the mechanisms regulating male sexual behavior in the absence of gonadal hormones. Recent studies have revealed several proteins that play a significant factor in regulating steroid-independent male sexual behavior in B6D2F1 male mice, including amyloid precursor protein (APP), tau, and synaptophysin. The specific goals of our study were to determine whether steroid-independent male sexual behavior was a heritable trait by determining if it was dependent upon the behavioral phenotype of the B6D2F1 sire, and whether the differential expression of APP, tau, and synaptophysin in the medial preoptic area found in the B6D2F1 sires that did and did not mate after gonadectomy was similar to those found in their male offspring. After adult B6D2F1 male mice were bred with C57BL/6J female mice, they and their male offspring (BXB1) were orchidectomized and identified as either maters or "non-maters". A significant proportion of the BXB1 maters was sired only from B6D2F1 maters, indicating that the steroid-independent male sexual behavior behavioral phenotype of the B6D2F1 hybrid males, when crossed with C57BL/6J female mice, is inherited by their male offspring. Additionally, APP, tau, and synaptophysin were elevated in in the medial preoptic area in both the B6D2F1 and BXB1 maters relative to the B6D2F1 and BXB1 non-maters, respectively, suggesting a potential genetic mechanism for the inheritance of steroid-independent male sexual behavior.

  3. Male sexual assault and rape: who seeks counseling?

    PubMed

    Monk-Turner, Elizabeth; Light, David

    2010-09-01

    This work rests on responses from 219 male sexual assault and rape victims who self-reported their victimization in the 1994-1996 Violence and Threats of Violence Against Women and Men in the United States survey. The authors expected that men who reported being severely assaulted would be more likely than others to seek counseling. They defined severely assaulted as having been penetrated, assaulted with a weapon, threatened, self-reported sustaining physical injuries, sought medical care, and/or reported the assault to the police. However, in their logistic model that explores who sought counseling, only one variable was significant. The odds of seeking counseling for men who reported being penetrated had significantly lower odds of seeking counseling all else equal.

  4. [MALE, FEMALE, NEUTRUM. SEXUAL IDENTITY, UNCERTAIN SEX AND BIOLOGY].

    PubMed

    Famularo, Simone

    2014-01-01

    For almost 2000 years, human beings have been discussing about gender. New scientific evidences give interesting new points of view, partially subverting the normal dichotomy described by the "two-gender" theory. In this article, we are going to critically review the history of the approach towards people born with a Sexual-Differentiation-Disorder, passing through the analysis of the Italian National Ethics Committee's opinion, describing the modern scientific evidences on the gender-identity development, furthermore ruling out the new approach borned from the femminist philosophies, and the new biogiuridical experiments borned in Australia and Germany. Would it be possible a world where a person could be more then a male or a female?

  5. Childhood Sexual Abuse, Attachments in Childhood and Adulthood, and Coercive Sexual Behaviors in Community Males.

    PubMed

    Langton, Calvin M; Murad, Zuwaina; Humbert, Bianca

    2017-04-01

    Associations between self-reported coercive sexual behavior against adult females, childhood sexual abuse (CSA), and child-parent attachment styles, as well as attachment with adult romantic partners, were examined among 176 adult community males. Attachment style with each parent and with romantic partners was also investigated as a potential moderator. Using hierarchical multiple regression analysis, avoidant attachment with mothers in childhood (and also with fathers, in a second model) accounted for a significant amount of the variance in coercive sexual behavior controlling for scores on anxious ambivalent and disorganized/disoriented attachment scales, as predicted. Similarly, in a third model, avoidance attachment in adulthood was a significant predictor of coercive sexual behavior controlling for scores on the anxiety attachment in adulthood scale. These main effects for avoidant and avoidance attachment were not statistically significant when CSA and control variables (other types of childhood adversity, aggression, antisociality, and response bias) were added in each of the models. But the interaction between scales for CSA and avoidance attachment in adulthood was significant, demonstrating incremental validity in a final step, consistent with a hypothesized moderating function for attachment in adulthood. The correlation between CSA and coercive sexual behavior was .60 for those with the highest third of avoidance attachment scores (i.e., the most insecurely attached on this scale), .24 for those with scores in the middle range on the scale, and .01 for those with the lowest third of avoidance attachment scores (i.e., the most securely attached). Implications for study design and theory were discussed.

  6. Apomorphine, deprenyl, and yohimbine fail to increase sexual behavior in rhesus males.

    PubMed

    Chambers, K C; Phoenix, C H

    1989-08-01

    Various doses of apomorphine, deprenyl, and yohimbine were administered to old (20-26 years) rhesus males that had been sexually active when younger and to younger (6-17 years) males that were characteristically sexually sluggish. These neuropharmacological agents have been reported to increase sexual behavior in male rats. In Experiment 1, 10 old intact rhesus males were tested after injection of vehicle and apomorphine, and 6 old testosterone-treated castrated males were tested after treatment with deprenyl and yohimbine and the vehicles for each drug. In experiment 2, the 5 younger males were tested after treatment with each of the drugs and with the vehicles for each drug. There were a few minor changes in behavior associated with certain doses of each of the drugs and as many depressive as facilitative effects on sexual behavior. This suggests that there are basic differences between rats and rhesus macaques in the systems mediating sexual behavior.

  7. [Cloning and expression of atp6 and atp9 genes from ramie (Boehmeria nivea (L.) Gaud.) and their relationship with cytoplasmic male sterility].

    PubMed

    Duan, Ji-Qiang; DU, Guang-Hui; Li, Jian-Yong; Liang, Xue-Ni; Liu, Fei-Hu

    2008-11-01

    The atp6 and apt9 gene fragments associated with cytoplasmic male sterility (CMS) were cloned from the mitochondrial DNA of a ramie (Boehmeria nivea (L.) Gaud.) cytoplasmic male sterile line and its maintainer and restorer lines using PCR and degenerated primer strategy. The primers were designed according to the reserved sequences in the encoding region of mitochondrial genes atp6 and atp9 of some dicotyledons from GenBank. These fragments did not have complete encoding region but showed the homology of 94% and 85% with atp6 and atp9 genes from the referred dicotyledons in GenBank. The complete atp6 and atp9 genes including the complete open reading frames were cloned by means of amplifying the 3' and 5'end unknown sequences of these gene fragments using DNA Walking method. The atp6 gene showed no difference among ramie male sterile line, maintainer and restorer lines at mtDNA sequence, transcription and translation control and protein level. However, compared to the maintainer and restorer lines, the atp9 gene of the male sterile line was different and deletion in several bases at the 3' end of the encoding region. An abnormally high expression of atp9 gene in the male sterile line at the budding stage and full-bloom stage was analyzed by RT-PCR analysis. These results indicated that the variation in DNA sequence and/or abnormality in expression of atp9 gene in the male sterile line maybe closely related to ramie CMS.

  8. Development, inheritance and breeding potential of a recessive genic male sterile line D248A in Sesame (Sesamum indicum L.).

    PubMed

    Liu, Hongyan; Yang, Minmin; Wu, Kun; Zhou, Xinan; Zhao, Yingzhong

    2013-01-01

    Genic male sterility (GMS) has great potential for heterosis exploitation in sesame (Sesamum indicum L.). Two spontaneous male-sterile plants were discovered in a Chinese sesame cultivar (Zhuzhi 4) in 2006. By consecutive sib mating with fertile plants from Zhuzhi 4, a new sterile line, D248A, was developed. Anatomy studies showed that D248A has thin, small and greenish anthers on which there are no or little pollen grains. The pollens are irregularly shaped and completely aborted, resulting in no germination and no formation of pollen tubes as revealed by acetocarmine stain or semi-solid suspension culture. Furthermore, D248A has a better performance in growth vigor, bloom duration and yield per plant than the other GMS lines (i.e. 95 ms-2A and 95 ms-5A). To investigate the inheritance mode of fertility, D248A was crossed and backcrossed with six varieties, and a segregating ratio of 3:1 and 1:1 for fertile and sterile plants was observed in F2 and BC1 populations, respectively. These results suggested that D248A is controlled by a recessive GMS gene. The average yield of four D248A-derived F1 hybrids is as high as 1695 kg·ha(-1), which is almost twice of that of 95 ms-5A-derived F1 hybrids. These results indicated that this newly developed recessive GMS line has great potential in sesame hybrid breeding.

  9. 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…

  10. Prevalence of and Risk Factors for Male Sexual Abuse: The Case of South Korea

    ERIC Educational Resources Information Center

    Han, In Young; Lee, Yongwoo; Yoo, Seo Koo; Hong, Jun Sung

    2011-01-01

    This study examined the prevalence of and risk factors for sexual abuse of boys in South Korea by asking a national sample of 1,043 adult males whether they had experienced sexual abuse during childhood. The results indicate that 13.5% experienced at least one of the nine types of child sexual abuse assessed. In addition, the majority of the…

  11. The Influence of Sexual Orientation and Sexual Role on Male Grooming-Related Injuries and Infections

    PubMed Central

    Gaither, Thomas W.; Truesdale, Matthew; Harris, Catherine R.; Alwaal, Amjad; Shindel, Alan W.; Allen, Isabel E.; Breyer, Benjamin N.

    2015-01-01

    Aim Pubic hair grooming is a common practice in the United States and coincides with prevalence of grooming-related injuries. Men who have sex with men (MSM) groom more frequently than men who have sex with women (MSW). We aim to characterize the influence of sexual orientation and sexual role on grooming behavior, injuries, and infections in men in the United States. Methods We conducted a nationally representative survey of noninstitutionalized adults aged 18–65 residing in the United States. We examined the prevalence and risk factors of injuries and infections that occur as a result of personal grooming. Results Of the 4,062 men who completed the survey, 3,176 (78.2%) report having sex with only women (MSW), 198 (4.9%) report sex with men (MSM), and 688 (16.9%) report not being sexually active. MSM are more likely to groom (42.5% vs. 29.0%, P < 0.001) and groom more around the anus, scrotum, and penile shaft compared with MSW. MSM receptive partners groom more often (50.9% vs. 26.9%, P = 0.005) and groom more for sex (85.3% vs. 51.9%, P < 0.001) compared with MSM insertive partners. MSM report more injuries to the anus (7.0% vs. 1.0%, P < 0.001), more grooming-related infections (7.0% vs. 1.0%, P < 0.001) and abscesses (8.8% vs. 2.5%, P = 0.010), as well as lifetime sexually transmitted infections (STIs) (1.65 vs. 1.45, P = 0.038) compared with MSW. More receptive partners report grooming at the time of their STI infection (52.2% vs. 14.3%, P < 0.001) compared with insertive partners. Conclusions Sexual orientation, and in particular sexual role, may influence male grooming behavior and impact grooming-related injuries and infections. Anogenital grooming may put one at risk for an STI. Healthcare providers should be aware of different grooming practices in order to better educate safe depilatory practices (i.e., the use of electric razors for anogenital grooming) in patients of all sexual orientations. PMID:25442701

  12. Transcriptomic Analysis of Differentially Expressed Genes during Flower Organ Development in Genetic Male Sterile and Male Fertile Tagetes erecta by Digital Gene-Expression Profiling.

    PubMed

    Ai, Ye; Zhang, Qinghua; Wang, Weining; Zhang, Chunling; Cao, Zhe; Bao, Manzhu; He, Yanhong

    2016-01-01

    Tagetes erecta is an important commercial plant of Asteraceae family. The male sterile (MS) and male fertile (MF) two-type lines of T. erecta have been utilized in F1 hybrid production for many years, but no report has been made to identify the genes that specify its male sterility that is caused by homeotic conversion of floral organs. In this study, transcriptome assembly and digital gene expression profiling were performed to generate expression profiles of MS and MF plants. A cDNA library was generated from an equal mixture of RNA isolated from MS and MF flower buds (1 mm and 4 mm in diameter). Totally, 87,473,431 clean tags were obtained and assembled into 128,937 transcripts among which 65,857 unigenes were identified with an average length of 1,188 bp. About 52% of unigenes (34,176) were annotated in Nr, Nt, Pfam, KOG/COG, Swiss-Prot, KO (KEGG Ortholog database) and/or GO. Taking the above transcriptome as reference, 125 differentially expressed genes were detected in both developmental stages of MS and MF flower buds. MADS-box genes were presumed to be highly related to male sterility in T. erecta based on histological and cytological observations. Twelve MADS-box genes showed significantly different expression levels in flower buds 4 mm in diameter, whereas only one gene expressed significantly different in flower buds 1 mm in diameter between MS and MF plants. This is the first transcriptome analysis in T. erecta and will provide a valuable resource for future genomic studies, especially in flower organ development and/or differentiation.

  13. Transcriptomic Analysis of Differentially Expressed Genes during Flower Organ Development in Genetic Male Sterile and Male Fertile Tagetes erecta by Digital Gene-Expression Profiling

    PubMed Central

    Ai, Ye; Zhang, Qinghua; Wang, Weining; Zhang, Chunling; Cao, Zhe; Bao, Manzhu; He, Yanhong

    2016-01-01

    Tagetes erecta is an important commercial plant of Asteraceae family. The male sterile (MS) and male fertile (MF) two-type lines of T. erecta have been utilized in F1 hybrid production for many years, but no report has been made to identify the genes that specify its male sterility that is caused by homeotic conversion of floral organs. In this study, transcriptome assembly and digital gene expression profiling were performed to generate expression profiles of MS and MF plants. A cDNA library was generated from an equal mixture of RNA isolated from MS and MF flower buds (1 mm and 4 mm in diameter). Totally, 87,473,431 clean tags were obtained and assembled into 128,937 transcripts among which 65,857 unigenes were identified with an average length of 1,188 bp. About 52% of unigenes (34,176) were annotated in Nr, Nt, Pfam, KOG/COG, Swiss-Prot, KO (KEGG Ortholog database) and/or GO. Taking the above transcriptome as reference, 125 differentially expressed genes were detected in both developmental stages of MS and MF flower buds. MADS-box genes were presumed to be highly related to male sterility in T. erecta based on histological and cytological observations. Twelve MADS-box genes showed significantly different expression levels in flower buds 4 mm in diameter, whereas only one gene expressed significantly different in flower buds 1 mm in diameter between MS and MF plants. This is the first transcriptome analysis in T. erecta and will provide a valuable resource for future genomic studies, especially in flower organ development and/or differentiation. PMID:26939127

  14. 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...

  15. 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.

  16. 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.

  17. Relational Challenges and Recovery Processes in Male Survivors of Childhood Sexual Abuse

    ERIC Educational Resources Information Center

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

    2010-01-01

    Male survivors of childhood sexual abuse face challenges resolving sexual victimization experiences with the ideals of masculinity, often experiencing intimacy problems, emotional discomfort, alienation, and anger. Little attention has been paid to how male survivors learn to develop long-term connections, disclose emotions in relationship…

  18. Male-to-Female Sexual Transmission of Zika Virus-United States, January-April 2016.

    PubMed

    Russell, Kate; Hills, Susan L; Oster, Alexandra M; Porse, Charsey Cole; Danyluk, Gregory; Cone, Marshall; Brooks, Richard; Scotland, Sarah; Schiffman, Elizabeth; Fredette, Carolyn; White, Jennifer L; Ellingson, Katherine; Hubbard, Allison; Cohn, Amanda; Fischer, Marc; Mead, Paul; Powers, Ann M; Brooks, John T

    2017-01-15

    We report on 9 cases of male-to-female sexual transmission of Zika virus in the United States occurring January-April 2016. This report summarizes new information about both timing of exposure and symptoms of sexually transmitted Zika virus disease, and results of semen testing for Zika virus from 2 male travelers.

  19. Understanding Sexual Minority Male Students' Meaning-Making about Their Multiple Identities: An Exploratory Comparative Study

    ERIC Educational Resources Information Center

    Tillapaugh, Daniel

    2016-01-01

    This exploratory comparative study examines the meaning-making experiences of six sexual minority males attending college or university in Canada or the United States. All of the participants identified as sexual minority males who were cisgender, out to family and/or friends, and between 20 and 24 years of age. In particular, the participants…

  20. 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…

  1. "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.…

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

    ERIC Educational Resources Information Center

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

    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…

  3. "Running a Train": Adolescent Boys' Accounts of Sexual Intercourse Involving Multiple Males and One Female

    ERIC Educational Resources Information Center

    Rothman, Emily F.; Decker, Michele R.; Reed, Elizabeth; Raj, Anita; Silverman, Jay G.; Miller, Elizabeth

    2008-01-01

    The authors used qualitative research methods to explore the context and sexual risk behavior associated with sexual intercourse involving multiple males and one female, commonly called "running a train." Participants were 20 adolescent males aged 14 to 22 years who were either perpetrators of dating violence or perceived by teachers to…

  4. SEXUAL INTERACTIONS WITH UNFAMILIAR FEMALES REDUCE HIPPOCAMPAL NEUROGENESIS AMONG ADULT MALE RATS

    PubMed Central

    Spritzer, Mark D.; Curtis, Molly G.; DeLoach, Julia P.; Maher, Jack; Shulman, Leanne M.

    2016-01-01

    Recent experiments have shown that sexual interactions prior to cell proliferation cause an increase in neurogenesis in adult male rats. Because adult neurogenesis is critical for some forms of memory, we hypothesized that sexually induced changes in neurogenesis may be involved in mate recognition. Sexually naive adult male rats were either exposed repeatedly to the same sexual partner (familiar group) or to a series of novel sexual partners (unfamiliar group), while control males never engaged in sexual interactions. Ovariectomized female rats were induced into estrus every four days. Males were given two injections of BrdU (200 mg/kg) to label proliferating cells, and the first sexual interactions occurred three days later. Males in the familiar and unfamiliar groups engaged in four, 30 min sexual interactions at four-day intervals, and brain tissue was collected the day after the last sexual interaction. Immunohisotchemistry followed by microscopy was used to quantify BrdU-labeled cells. Sexual interactions with unfamiliar females caused a significant reduction in neurogenesis in the dentate gyrus compared to males that interacted with familiar females and compared to the control group. The familiar group showed no difference in neurogenesis compared to the control group. There were no differences in the amount of sexual behavior (mounts, intromissions, ejaculations, or contact time) that the familiar and unfamiliar groups engaged in, indicating that the differences in neurogenesis were not due to the relative amounts of sexual activity. In a second experiment, we tested whether this effect was unique to sexual interactions by replicating the entire procedure using anestrus females. We found that interactions with unfamiliar anestrus females reduced neurogenesis relative to the other groups, but this effect was not statistically significant. In combination, these results indicate that interactions with unfamiliar females reduce adult neurogenesis and the effect

  5. Eurycoma Longifolia as a potential adoptogen of male sexual health: a systematic review on clinical studies.

    PubMed

    Thu, Hnin Ei; Mohamed, Isa Naina; Hussain, Zahid; Jayusman, Putri Ayu; Shuid, Ahmad Nazrun

    2017-01-01

    Eurycoma longifolia (EL) has been well recognized as a booster of male sexual health. Over the past few decades, numerous in vivo animal studies and human clinical trials have been conducted across the globe to explore the promising role of EL in managing various male sexual disorders, which include erectile dysfunction, male infertility, low libido, and downregulated testosterone levels. The aim of the present review is to analyze and summarize the literature on human clinical trials which revealed the clinical significance and therapeutic feasibility of EL in improving male sexual health. This systematic review is focused on the following databases: Medline, Wiley Online Library, BioMed Central, Hindawi, Web of Knowledge, PubMed Central and Google Scholar, using search terms such as "Eurycoma longifolia", "EL", "Tongkat Ali", "male sexual health", "sexual infertility", "erectile dysfunction", "male libido", and "testosterone levels". Notably, only human clinical studies published between 2000 and 2014 were selected and thoroughly reviewed for relevant citations. Out of 150 articles, 11 met the inclusion criteria. The majority of articles included were randomized placebo-controlled trials, multiple cohort studies, or pilot trials. All these studies demonstrated considerable effects of EL on male sexual health disorders. Among them, 7 studies revealed remarkable association between the use of EL and the efficacy in the treatment of male sexual disorders, and remaining 4 studies failed to demonstrate sufficient effects on male sexual health. In summary, there is convincing evidence for the prominence of EL in improving the male sexual health. The review also substantiates the use of current methodology in the development of novel and more rationale natural herbal medicines for the management of male sexual disorders.

  6. Rethinking Sexual Initiation: Pathways to Identity Formation among Gay and Bisexual Mexican Male Youth

    PubMed Central

    Carrillo, Héctor; Fontdevila, Jorge

    2010-01-01

    The topic of same-sex sexual initiation has generally remained understudied in the literature on sexual identity formation among sexual minority youth. This article analyzed 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

  7. 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.

  8. Cytological basis of sterility in male and female hybrids between sibling species of grey voles Microtus arvalis and M. levis

    PubMed Central

    Torgasheva, Anna A.; Borodin, Pavel M.

    2016-01-01

    To make insight into the cytological basis of reproductive isolation, we examined chromosome synapsis and recombination in sterile male and female hybrids between Microtus arvalis and M. levis. These sibling species differ by a series of chromosomal rearrangements (fusions, inversions, centromere shifts and heterochromatin insertions). We found that meiosis in male hybrids was arrested at leptotene with complete failure of chromosome pairing and DNA double-strand breaks repair. In the female hybrids meiosis proceeded to pachytene; however, the oocytes varied in the degree of pairing errors. Some of them demonstrated almost correct chromosome pairing, while most of them contained a varying number of univalents and multivalents with extensive regions of asynapsis and non-homologous synapsis. Variation between oocytes was probably caused by stochasticity in the ratio of homologous to non-homologous pairing initiations. We suggest that substantial chromosomal and genetic divergence between the parental species affects preliminary alignment of homologues, homology search and elimination of ectopic interhomologue interactions that are required for correct homologous pairing. Apparently, pairing failure in male and aberrant synapsis in female vole hybrids followed by meiotic silencing of unsynapsed chromatin cause apoptosis of gametocytes and sterility. PMID:27811955

  9. Determination of cytoplasmic male sterile factors in onion plants (Allium cepa L.) using PCR-RFLP and SNP markers.

    PubMed

    Cho, Kwang-Soo; Yang, Tae-Jin; Hong, Su-Young; Kwon, Young-Seok; Woo, Jong-Gyu; Park, Hyo-Guen

    2006-06-30

    We have developed a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) marker that can distinguish male-fertile (N) and male-sterile (S) cytoplasm in onions. The PCR-RFLP marker was located in a chloroplast psbA gene amplicon. Digesting the amplicons from different cytoplasm-containing varieties with the restriction enzyme MspI revealed that N-cytoplasm plants have a functional MspI site (CCGG), whereas the S-cytoplasm plants has a substitution in that site (CTGG), and thus no MspI target. The results obtained using this PCR-RFLP marker to distinguish between cytoplasmic male sterile factors in 35 onion varieties corresponded with those using a CMS-specific sequence-characterized amplified region (SCAR) marker. Moreover, the PCR-RFLP marker can identify N- ot S-cytoplasms in DNA sample mixtures in which they are in up to a 10-fold minority, indicating that use of the marker has high diagnostic precision. We also demonstrated the usefulness of the SNP detected in the psbA gene for high-throughput discrimination of CMS factors using Real-time PCR and a TaqMan probe assay.

  10. Male-male sexual behavior in Japanese quail: being "on top" reduces mating and fertilization with females.

    PubMed

    Adkins-Regan, Elizabeth

    2014-10-01

    Male Japanese quail (Coturnix japonica) engage in vigorous same-sex sexual interactions that have been interpreted as aggressive behavior reflecting dominance relationships. The consequences of this behavior for reproductive success, and whether it is a form of competition over mating and fertilization, are unclear. Three experiments were conducted to determine the effect of seeing or interacting with another male on a male's subsequent mating and fertilization success with females. A vigorous interaction with another male in which the subject performed more cloacal contact movements (movements to try to make contact with the other bird's cloacal opening) reduced subsequent mating and fertilization success with a female to a similar extent as a prior mating with a different female. Receiving one or more cloacal contacts from another male was less detrimental for subsequent success. The mere presence of another (stimulus) male delayed mating initiation in those male subjects that approached the stimulus first instead of the female. These results do not support the idea that the male "on top" in male-male sexual interactions is the dominant bird who goes on to achieve greater reproductive success. Instead, the results are consistent with male-male sexual behavior as an occasionally costly by-product of strong mating motivation.

  11. Cytological characterization of a thermo-sensitive cytoplasmic male-sterile wheat line having K-type cytoplasm of Aegilops kotschyi

    PubMed Central

    Meng, Liying; Liu, Zihan; Zhang, Lingli; Hu, Gan; Song, Xiyue

    2016-01-01

    Male sterility is an important tool for obtaining crop heterosis. A thermo-sensitive cytoplasmic male-sterile (TCMS) line was developed recently using a new method based on tiller regeneration. In the present study, we explored the critical growth stages required to maintain thermo-sensitive male sterility in TCMS lines and found that fertility is associated with abnormal tapetal and microspore development. We investigated the fertility and cytology of temperature-treated plant anthers at various developmental stages. TCMS line KTM3315A exhibited thermo-sensitive male sterility in Zadoks growth stages 41–49 and 58–59. Morphologically, the line exhibited thermo-sensitive male sterility at 3–9 days before heading and at 3–6 days before flowering, and it was partially restored in three locations during spring and summer. TCMS line KTM3315A plants exhibited premature tapetal programmed cell death (PCD) from the early uninucleate stage of microspore development until the tapetal cells degraded completely. Microspore development was then blocked and the pollen abortion type was stainable abortion. Thus, male fertility in the line KTM3315A is sensitive to temperature and premature tapetal PCD is the main cause of pollen abortion, where it determines the starting period and affects male fertility conversion in K-type TCMS lines at certain temperatures. PMID:28163591

  12. Cytological characterization of a thermo-sensitive cytoplasmic male-sterile wheat line having K-type cytoplasm of Aegilops kotschyi.

    PubMed

    Meng, Liying; Liu, Zihan; Zhang, Lingli; Hu, Gan; Song, Xiyue

    2016-12-01

    Male sterility is an important tool for obtaining crop heterosis. A thermo-sensitive cytoplasmic male-sterile (TCMS) line was developed recently using a new method based on tiller regeneration. In the present study, we explored the critical growth stages required to maintain thermo-sensitive male sterility in TCMS lines and found that fertility is associated with abnormal tapetal and microspore development. We investigated the fertility and cytology of temperature-treated plant anthers at various developmental stages. TCMS line KTM3315A exhibited thermo-sensitive male sterility in Zadoks growth stages 41-49 and 58-59. Morphologically, the line exhibited thermo-sensitive male sterility at 3-9 days before heading and at 3-6 days before flowering, and it was partially restored in three locations during spring and summer. TCMS line KTM3315A plants exhibited premature tapetal programmed cell death (PCD) from the early uninucleate stage of microspore development until the tapetal cells degraded completely. Microspore development was then blocked and the pollen abortion type was stainable abortion. Thus, male fertility in the line KTM3315A is sensitive to temperature and premature tapetal PCD is the main cause of pollen abortion, where it determines the starting period and affects male fertility conversion in K-type TCMS lines at certain temperatures.

  13. Sterile inflammation as a factor in human male infertility: Involvement of Toll like receptor 2, biglycan and peritubular cells

    PubMed Central

    Mayer, C.; Adam, M.; Glashauser, L.; Dietrich, K.; Schwarzer, J.U.; Köhn, F.-M.; Strauss, L.; Welter, H.; Poutanen, M.; Mayerhofer, A.

    2016-01-01

    Changes in the wall of seminiferous tubules in men with impaired spermatogenesis imply sterile inflammation of the testis. We tested the hypothesis that the cells forming the wall of seminiferous tubules, human testicular peritubular cells (HTPCs), orchestrate inflammatory events and that Toll like receptors (TLRs) and danger signals from the extracellular matrix (ECM) of this wall are involved. In cultured HTPCs we detected TLRs, including TLR2. A TLR-2 ligand (PAM) augmented interleukin 6 (IL-6), monocyte chemo-attractant protein-1 (MCP-1) and pentraxin 3 (PTX3) in HTPCs. The ECM-derived proteoglycan biglycan (BGN) is secreted by HTPCs and may be a TLR2-ligand at HTPCs. In support, recombinant human BGN increased PTX3, MCP-1 and IL-6 in HTPCs. Variable endogenous BGN levels in HTPCs derived from different men and differences in BGN levels in the tubular wall in infertile men were observed. In testes of a systemic mouse model for male infertility, testicular sterile inflammation and elevated estradiol (E2) levels, BGN was also elevated. Hence we studied the role of E2 in HTPCs and observed that E2 elevated the levels of BGN. The anti-estrogen ICI 182,780 blocked this action. We conclude that TLR2 and BGN contribute to sterile inflammation and infertility in man. PMID:27849015

  14. 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

  15. [Preliminary gene-mapping of photoperiod-temperature sensitive genic male sterility in wheat (Triticum aestivum L.)].

    PubMed

    Cao, Shuang-He; Guo, Xiao-Li; Liu, Dong-Cheng; Zhang, Xiang-Qi; Zhang, Ai-Min

    2004-03-01

    The photoperiod-temperature sensitive genic male sterile (PTSGMS) line in wheat is important for the utilization of heterosis. The wheat line, BAU3338, is an excellent PTSGMS material identified in the recent years. In this study, its PTSGMS genes were mapped using molecular markers, SSR and ISSR. The result of molecular analysis showed that the two PTSGMS loci were identified and designated as ptms1 and ptms2, respectively. In addition, the genetic effect analysis indicated that the locus effect of ptms1 was 2-3 times larger than that of ptms2.

  16. Syndemics and gender affirmation: HIV sexual risk in female-to-male trans masculine adults reporting sexual contact with cisgender males

    PubMed Central

    Reisner, Sari L; Hughto, Jaclyn M White; Pardee, Dana; Sevelius, Jae

    2015-01-01

    Female-to-male trans masculine adults who have sex with cisgender (non-transgender) males (TMSM) represent an understudied population in relation to HIV/STI risk. This study examined the role of syndemic conditions and social gender affirmation processes (living full-time in one’s identified gender) in potentiating sexual risk among TMSM adults in Massachusetts. Cross-sectional data were restricted to TMSM who reported lifetime sexual behaviour with a cisgender male (n = 173; mean age = 29.4, SD = 9.6; 18.5% people of colour; 93.1% non-heterosexual identity; 56.1% hormones/surgery). Sexual risk outcomes were: lifetime STI diagnoses, three or more past-6-month sexual partners, and condomless anal/vaginal sex at last encounter with a cisgender male. Age- and survey mode-adjusted logistic regression models regressed sexual risk outcomes on the main effect of syndemics (six indicators summed: binge drinking, substance use, depression, anxiety, childhood abuse, intimate partner violence), followed by the interaction of syndemics and social gender affirmation. Syndemics were associated with increased odds of all sexual risk indicators (adjusted odds ratios (aORs) = 1.32–1.55; p < 0.0001). Social gender affirmation moderated the association between syndemics and condomless anal/vaginal sex at last encounter with a cisgender male (p < 0.0001). Syndemics were associated with sexual risk in TMSM who had socially affirmed their gender (aOR = 1.79; 95% CI = 1.42–2.25; p < 0.001), but not among those TMSM who had not (aOR = 0.86; 95% CI = 0.63–1.19; p = 0.37). Findings suggest that syndemic pathways to sexual risk are similar for TMSM who have socially gender affirmed as for cisgender MSM. Integration of syndemics and gender affirmation frameworks is recommended in interventions to address TMSM sexual risk. PMID:26384946

  17. Sexual health knowledge, sexual relationships and condom use among male trekking guides in Nepal: a qualitative study.

    PubMed

    Simkhada, Padam; van Teijlingen, Edwin R; Regmi, Pramod R; Bhatta, Prakash

    2010-01-01

    People in Nepal generally hold fairly traditional views about sex and sexual health, whilst Western tourists often have a more liberal approach towards sex and relationships. There is evidence that significant sexual interaction occurs between male trekking guides and female travellers and/or local female sex workers in Nepal. This qualitative study explored trekking guides' sexual health knowledge, sexual relationships and condom use with female trekkers and local female sex workers. A total of 21 in-depth interviews were conducted with male trekking guides. Most reported having had sexual relationships with female trekkers and local female sex workers. Explanations for intercourse with female trekkers included: financial support; getting future trekkers through word-of-mouth advertising from the women they have had sex with; and opportunities for emigration. Interestingly, sexual intercourse is reported as more likely to be initiated by female trekkers than by guides, and more so by older women. In contrast, the main reasons for having sex with local female sex workers included: romantic love or sexual excitement and novelty. Awareness regarding sexual health was high among guides, but several factors discouraged the regular use of condoms. Further research with female tourists would help understand the motivations and reasons for their sexual behaviour.

  18. Comparing Indicators of Sexual Sadism as Predictors of Recidivism among Adult Male Sexual Offenders

    ERIC Educational Resources Information Center

    Kingston, Drew A.; Seto, Michael C.; Firestone, Philip; Bradford, John M.

    2010-01-01

    Objective: In this longitudinal study, the predictive validity of a psychiatric diagnosis of sexual sadism was compared with three behavioral indicators of sadism: index sexual offense violence, sexual intrusiveness, and phallometrically assessed sexual arousal to depictions of sexual or nonsexual violence. Method: Five hundred and eighty six…

  19. Impact of Salivary Gland Hypertrophy Virus Infection on the Mating Success of Male Glossina pallidipes: Consequences for the Sterile Insect Technique

    PubMed Central

    Mutika, Gratian N.; Marin, Carmen; Parker, Andrew G.; Boucias, Drion G.; Vreysen, Marc J. B.; Abd-Alla, Adly M. M.

    2012-01-01

    Many species of tsetse flies are infected by a virus (GpSGHV) that causes salivary gland hypertrophy (SGH). Female Glossina pallidipes (Austen) with SGH symptoms (SGH+) have reduced fecundity and SGH+ male G. pallidipes are unable to inseminate female flies. Consequently, G. pallidipes laboratory colonies with a high prevalence of SGH have been difficult to maintain and have collapsed on several occasions. To assess the potential impact of the release of SGH+ sterile male G. pallidipes on the efficacy of an integrated control programme with a sterile insect technique (SIT) component, we examined the mating efficiency and behaviour of male G. pallidipes in field cages in relation to SGH prevalence. The results showed in a field cage setting a significantly reduced mating frequency of 19% for a male G. pallidipes population with a high prevalence of SGH (83%) compared to 38% for a male population with a low prevalence of SGH (7%). Premating period and mating duration did not vary significantly with SGH status. A high percentage (>80%) of females that had mated with SGH+ males had empty spermathecae. The remating frequency of female G. pallidipes was very low irrespective of the SGH status of the males in the first mating. These results indicate that a high prevalence of SGH+ in G. pallidipes not only affects colony stability and performance but, in view of their reduced mating propensity and competitiveness, releasing SGH+ sterile male G. pallidipes will reduce the efficiency of a sterile male release programme. PMID:22912687

  20. 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…

  1. Effect of aqueous extract of Arctium lappa L. (burdock) roots on the sexual behavior of male rats

    PubMed Central

    2012-01-01

    Background Arctium lappa L. root has traditionally been recommended as an aphrodisiac agent. It is used to treat impotence and sterility in China, and Native Americans included the root in herbal preparations for women in labor. However, its use has not been scientifically validated. The present study therefore investigated the effects of aqueous extract of Arctium lappa L. roots on sexual behavior in normal male rats. Methods Seventy-five albino male rats were randomly divided into five groups of 15 rats each. Rats in group 1 (control) were administered 10 mL⁄kg body weight distilled water (vehicle), group 2 received 60 mg/kg body weight sildenafil citrate (Viagra), while those in groups 3, 4, and 5 were given 300, 600, and 1,200 mg/kg body weight, respectively, of aqueous extract of Arctium lappa L. roots in the same volume. Female albino rats were made receptive by hormonal treatment. Sexual behavior parameters in male rats were monitored on days 3, 7 and 15 by pairing with receptive females (1:3). Male serum testosterone concentrations and potency were also determined. Results Oral administration of Arctium lappa L. roots extract at 600 and 1,200 mg/kg body weight significantly increased the frequencies of mount, intromission, and ejaculation frequency (p < 0.05). The latencies of mount and intromission were significantly reduced and ejaculation latency was prolonged. Administration of the extract also reduced the post-ejaculatory interval. The standard drug (Viagra) was more effective than the extract. The extract significantly increased the frequencies of all components of penile reflexes as well as serum testosterone levels, compared with the distilled water controls. Conclusions The results of this study demonstrate that aqueous extract of Arctium lappa L. roots enhances sexual behavior in male rats. The aphrodisiac effects of the plant extract may be related to the presence of flavonoids, saponins, lignans and alkaloids, acting via a multitude of central

  2. Identification and Functional Analysis of microRNAs Involved in the Anther Development in Cotton Genic Male Sterile Line Yu98-8A

    PubMed Central

    Yang, Xiaojie; Zhao, Yuanming; Xie, Deyi; Sun, Yao; Zhu, Xunlu; Esmaeili, Nardana; Yang, Zuoren; Wang, Ye; Yin, Guo; Lv, Shuping; Nie, Lihong; Tang, Zhongjie; Zhao, Fu’an; Li, Wu; Mishra, Neelam; Sun, Li; Zhu, Wei; Fang, Weiping

    2016-01-01

    Hybrid vigor contributes in a large way to the yield and quality of cotton (Gossypium hirsutum) fiber. Although microRNAs play essential regulatory roles in flower induction and development, it is still unclear if microRNAs are involved in male sterility, as the regulatory molecular mechanisms of male sterility in cotton need to be better defined. In this study, two independent small RNA libraries were constructed and sequenced from the young buds collected from the sporogenous cell formation to the meiosis stage of the male sterile line Yu98-8A and the near-isogenic line. Sequencing revealed 1588 and 1536 known microRNAs and 347 and 351 novel miRNAs from male sterile and male fertile libraries, respectively. MicroRNA expression profiles revealed that 49 conserved and 51 novel miRNAs were differentially expressed. Bioinformatic and degradome analysis indicated the regulatory complexity of microRNAs during flower induction and development. Further RT-qPCR and physiological analysis indicated that, among the different Kyoto Encyclopedia Gene and Genomes pathways, indole-3-acetic acid and gibberellic acid signaling transduction pathways may play pivotal regulatory functions in male sterility. PMID:27739413

  3. The sexual victimization of male children: a review of previous research.

    PubMed

    Vander Mey, B J

    1988-01-01

    The evidence available at this time indicates that male children are more likely to be abused by nonfamily rather than family members. Residing in a neglectful home or a mother-headed household and having previous homosexual contact tend to heighten risk for sexual abuse by nonfamily members. Familial sexual abuse appears related to residence in a home where other siblings are being abused, where the father was a victim of sexual abuse as a child, and where parents suffer myriad personal and social adjustment difficulties. Effects of male child sexual abuse appear to be serious and long lasting. The scant writings available at this time imply that the sexually abused male child experiences a range of adjustment and self-esteem problems as an adult and may be at heightened risk to become a child sexual abuser.

  4. The Blood-Testis Barrier and Male Sexual Dysfunction following Spinal Cord Injury

    DTIC Science & Technology

    2014-10-01

    AWARD NUMBER: W81XWH-12-1-0481 TITLE: The Blood-Testis Barrier and Male Sexual Dysfunction following Spinal Cord Injury PRINCIPAL INVESTIGATOR...AND SUBTITLE: l The Blood-Testis Barrier and Male Sexual Dysfunction following Spinal Cord Injury 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-12-1...for Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT A majority of males exhibit a profound loss of fertility following

  5. Steroid-independent male sexual behavior in B6D2F2 male mice.

    PubMed

    McInnis, Christine M; Venu, Samitha; Park, Jin Ho

    2016-09-01

    It is well established that male sexual behavior (MSB) is regulated by gonadal steroids; however, individual differences in MSB, independent of gonadal steroids, are prevalent across a wide range of species, and further investigation is necessary to advance our understanding of steroid-independent MSB. Studies utilizing B6D2F1 hybrid male mice in which a significant proportion retain MSB after long-term orchidectomy, identified as steroid-independent-maters (SI-maters), have begun to unravel the genetic underpinnings of steroid-independent MSB. A recent study demonstrated that steroid-independent MSB is a heritable behavioral phenotype that is mainly passed down from B6D2F1 hybrid SI-maters when crossed with C57BL6J female mice. To begin to uncover whether the strain of the dam plays a role in the inheritance of steroid-independent MSB, B6D2F1 hybrid females were crossed with B6D2F1 hybrid males. While the present study confirms the finding that steroid-independent MSB is a heritable behavioral phenotype and that SI-mater sires are more likely to pass down some components of MSB than SI-non-maters to their offspring, it also reveals that the B6D2F2 male offspring that were identified as SI-maters that displayed the full repertoire of steroid-independent MSB had the same probability of being sired from either a B6D2F1 SI-mater or SI-non-mater. These results, in conjunction with previous findings, indicate that the specific chromosomal loci pattern that codes for steroid-independent MSB in the B6D2F2 male offspring may result regardless of whether the father was a SI-mater or SI-non-mater, and that the maternal strain may be an important factor in the inheritance of steroid-independent MSB.

  6. Reduced expression of CDP-DAG synthase changes lipid composition and leads to male sterility in Drosophila

    PubMed Central

    Laurinyecz, Barbara; Péter, Mária; Vedelek, Viktor; Kovács, Attila L.; Juhász, Gábor; Maróy, Péter; Vígh, László; Balogh, Gábor; Sinka, Rita

    2016-01-01

    Drosophila spermatogenesis is an ideal system to study the effects of changes in lipid composition, because spermatid elongation and individualization requires extensive membrane biosynthesis and remodelling. The bulk of transcriptional activity is completed with the entry of cysts into meiotic division, which makes post-meiotic stages of spermatogenesis very sensitive to even a small reduction in gene products. In this study, we describe the effect of changes in lipid composition during spermatogenesis using a hypomorphic male sterile allele of the Drosophila CDP-DAG synthase (CdsA) gene. We find that the CdsA mutant shows defects in spermatid individualization and enlargement of mitochondria and the axonemal sheath of the spermatids. Furthermore, we could genetically rescue the male sterile phenotype by overexpressing Phosphatidylinositol synthase (dPIS) in a CdsA mutant background. The results of lipidomic and genetic analyses of the CdsA mutant highlight the importance of correct lipid composition during sperm development and show that phosphatidic acid levels are crucial in late stages of spermatogenesis. PMID:26791243

  7. PMS1T, producing phased small-interfering RNAs, regulates photoperiod-sensitive male sterility in rice

    PubMed Central

    Fan, Yourong; Yang, Jiangyi; Mathioni, Sandra M.; Yu, Jinsheng; Shen, Jianqiang; Yang, Xuefei; Wang, Lei; Zhang, Qinghua; Cai, Zhaoxia; Xu, Caiguo; Li, Xianghua; Xiao, Jinghua; Zhang, Qifa

    2016-01-01

    Phased small-interfering RNAs (phasiRNAs) are a special class of small RNAs, which are generated in 21- or 24-nt intervals from transcripts of precursor RNAs. Although phasiRNAs have been found in a range of organisms, their biological functions in plants have yet to be uncovered. Here we show that phasiRNAs generated by the photopheriod-sensetive genic male sterility 1 (Pms1) locus were associated with photoperiod-sensitive male sterility (PSMS) in rice, a germplasm that started the two-line hybrid rice breeding. The Pms1 locus encodes a long-noncoding RNA PMS1T that was preferentially expressed in young panicles. PMS1T was targeted by miR2118 to produce 21-nt phasiRNAs that preferentially accumulated in the PSMS line under long-day conditions. A single nucleotide polymorphism in PMS1T nearby the miR2118 recognition site was critical for fertility change, likely leading to differential accumulation of the phasiRNAs. This result suggested possible roles of phasiRNAs in reproductive development of rice, demonstrating the potential importance of this RNA class as regulators in biological processes. PMID:27965387

  8. Fine mapping of the epistatic suppressor gene (esp) of a recessive genic male sterility in rapeseed (Brassica napus L.).

    PubMed

    Xu, Zhenghua; Xie, Yanzhou; Hong, Dengfeng; Liu, Pingwu; Yang, Guangsheng

    2009-09-01

    9012AB, a recessive genic male sterility (RGMS) line derived from spontaneous mutation in Brassica napus, has been playing an important role in rapeseed hybrid production in China. The male sterility of 9012AB is controlled by two recessive genes (ms3 and ms4) interacting with one recessive epistatic suppressor gene (esp). The objective of this study was to develop PCR-based markers tightly linked to the esp gene and construct a high-resolution map surrounding the esp gene. From the survey of 512 AFLP primer combinations, 3 tightly linked AFLP markers were obtained and successfully converted to codominant or dominant SCAR markers. Furthermore, a codominant SSR marker (Ra2G08) associated with the esp gene was identified through genetic map integration. For fine mapping of the esp gene, these PCR-based markers were analyzed in a large BC1 population of 2545 plants. The esp gene was then genetically restricted to a region of 1.03 cM, 0.35 cM from SSR marker Ra2G08 and 0.68 cM from SCAR marker WSC6. The SCAR marker WSC5 co-segregated with the target gene. These results lay a solid foundation for map-based cloning of esp and will facilitate the selection of RGMS lines and their temporary maintainers.

  9. Aberrant Meiotic Prophase I Leads to Genic Male Sterility in the Novel TE5A Mutant of Brassica napus

    PubMed Central

    Yan, Xiaohong; Zeng, Xinhua; Wang, Shasha; Li, Keqi; Yuan, Rong; Gao, Hongfei; Luo, Junling; Liu, Fang; Wu, Yuhua; Li, Yunjing; Zhu, Li; Wu, Gang

    2016-01-01

    Genic male sterility (GMS) has already been extensively utilized for hybrid rapeseed production. TE5A is a novel thermo-sensitive dominant GMS line in Brassica napus, however, its mechanisms of GMS remain largely unclear. Histological and Transmission electron microscopy (TEM) analyses of anthers showed that the male gamete development of TE5A was arrested at meiosis prophase I. EdU uptake of S-phase meiocytes revealed that the TE5A mutant could accomplish DNA replication, however, chromosomal and fluorescence in situ hybridization (FISH) analyses of TE5A showed that homologous chromosomes could not pair, synapse, condense and form bivalents. We then analyzed the transcriptome differences between young floral buds of sterile plants and its near-isogenic fertile plants through RNA-Seq. A total of 3,841 differentially expressed genes (DEGs) were obtained, some of which were associated with homologous chromosome behavior and cell cycle control during meiosis. Dynamic expression changes of selected candidate DEGs were then analyzed at different anther developmental stages. The present study not only demonstrated that the TE5A mutant had defects in meiotic prophase I via detailed cytological analysis, but also provided a global insight into GMS-associated DEGs and elucidated the mechanisms of GMS in TE5A through RNA-Seq. PMID:27670217

  10. Lesions in the medial posterior region of the BST impair sexual behavior in sexually experienced and inexperienced male rats.

    PubMed

    Claro, F; Segovia, S; Guilamón, A; Del Abril, A

    1995-01-01

    Previous studies have showed that lesions in the bed nucleus of the stria terminalis of experienced male rats impair some parameters of sexual behavior. The aim of this study was to examine the contribution of the medial posterior region of the bed nucleus of the stria terminalis (BSTMP), a sexually dimorphic region of this nucleus that pertains to the vomeronasal system, to the modulation of sexual behavior of the male rat. Small electrolytic bilateral lesions in the BSTMP were made in male heterosexual experienced and inexperienced rats. Sham lesioned animals were also tested as a control of the effects of the general surgical procedures. Behavioral tests were then performed to obtain standard measures of masculine sexual behavior. Our results indicate that the sexually experienced male rats with lesioned BSTMPs showed increases in the number of mounts and the number of intromissions and, consequently, in ejaculation latency. In contrast, the sexually naive male rats showed increases in first mount and intromission latencies and in ejaculation latency, but the latter occurred due to increases in the interintromission intervals. This group also showed low correlations between olfactory investigation of the anogenital area of the female and initiation and maintenance of copulatory behavior. The results suggest that sexual experience obtained in the very artificial conditions of laboratory tests could supply some of the cues provided by the BSTMP in the process of sensorial integration, which we hypothesize modulates the initiation and pacing of copulation. However, sexual experience does not apparently supply any other kinds of cues provided or processed in the BSTMP that are involved in modulating the elicitation of intromissions and ejaculations.

  11. Sexual conflict and the evolution of female mate choice and male social dominance.

    PubMed

    Moore, A J; Gowaty, P A; Wallin, W G; Moore, P J

    2001-03-07

    Conflicts between the sexes over control of reproduction are thought to lead to a cost of sexual selection through the evolution of male traits that manipulate female reproductive physiology and behaviour, and female traits that resist this manipulation. Although studies have begun to document negative fitness effects of sexual conflict, studies showing the expected association between sexual conflict and the specific behavioural mechanisms of sexual selection are lacking. Here we experimentally manipulated the opportunity for sexual conflict in the cockroach. Nauphoeta cinerea and showed that, for this species, odour cues in the social environment influence the behavioural strategies and fitness of males and females during sexual selection. Females provided with the opportunity for discriminating between males but not necessarily mating with preferred males produced fewer male offspring than females mated at random. The number of female offspring produced was not affected, nor was the viability of the offspring. Experimental modification of the composition of the males' pheromone showed that the fecundity effects were caused by exposure to the pheromone component that makes males attractive to females but also makes males less likely to be dominant. Female mate choice therefore carries a demographic cost but functions to avoid male manipulation and aggression. Male-male competition appears to function to circumvent mate choice rather than directly manipulating females, as the mate choice can be cryptic. The dynamic struggle between the sexes for control of mating opportunities and outcomes in N. cinerea therefore reveals a unique role for sexual conflict in the evolution of the behavioural components of sexual selection.

  12. 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

  13. Genetics of reproductive isolation in the Drosophila simulans clade: DNA marker-assisted mapping and characterization of a hybrid-male sterility gene, Odysseus (Ods).

    PubMed

    Perez, D E; Wu, C I; Johnson, N A; Wu, M L

    1993-05-01

    In this study, we address the question of whether there exist major genes that cause complete male sterility in the interspecific hybrids of Drosophila and, if they do, how these genes may be characterized at the molecular level. Our approach is to introgress small segments of the X chromosome from Drosophila mauritiana (or Drosophila sechellia) into Drosophila simulans by repeated backcrosses for more than 20 generations. The introgressions are monitored by both visible mutations and a series of DNA markers. We compare the extent of introgressions that cause male sterility with those that do not. If a major sterility factor exists, there should be a sharp boundary between these two classes of introgressions and their breakpoints should demarcate such a gene. Furthermore, if male sterility is the only major fitness effect associated with the introgression, recombination analysis should yield a pattern predicted by the classical three-point cross. Both the genetic and molecular analyses suggest the presence of a major sterility factor from D. mauritiana, which we named Odysseus (Ods), in the cytological interval of 16D. We thus formalize three criteria for inferring the existence of a major gene within an introgression: (1) complete penetrance of sterility, (2) complementarity in recombination analysis, and (3) physical demarcation. Introgressions of Ods from D. sechellia do not cause sterility. Twenty-two introgressions in our collection have breakpoints in this interval of about 500 kb, making it possible to delineate Ods more precisely for molecular identification. The recombination analysis also reveals the complexity of the introgressed segments--even relatively short ones may contain a second male sterility factor and partial viability genes and may also interfere with crossovers. The spermatogenic defects associated with Ods and/or a second factor were characterized by phase-contrast microscopy.

  14. Toward improved interpretation and theory building of African American male sexualities.

    PubMed

    Lewis, Linwood J; Kertzner, Robert M

    2003-11-01

    This paper examined five challenges to clear understanding of African American male sexualities: incorrect assumptions of African American homogeneity; an underemphasis on developmental change, the contexts and the meanings of sexual behaviors; and a lack of compelling theoretical grounding for African American sexualities. Critical elements for effective theorizing and research about African American sexualities (i.e. multiple levels of analysis, examination of phenomenological meaning of sexuality, measurement of dynamic/developmental change) were outlined and candidate theories within sexual science (social exchange theories, symbolic interactionism, sexual scripting theory) were analyzed in light of these elements. It is suggested that a re-orientation of sex research about African American men using these elements will result in improved understanding of African American sexualities in multiple contexts.

  15. The contrasting role of male relatedness in different mechanisms of sexual selection in red junglefowl

    PubMed Central

    Tan, Cedric Kai Wei; Doyle, Philippa; Bagshaw, Emma; Richardson, David S.; Wigby, Stuart; Pizzari, Tommaso

    2017-01-01

    In structured populations, competition for reproductive opportunities should be relaxed among related males. The few tests of this prediction often neglect the fact that sexual selection acts through multiple mechanisms, both before and after mating. We performed experiments to study the role of within‐group male relatedness across pre‐ and postcopulatory mechanisms of sexual selection in social groups of red junglefowl, Gallus gallus, in which two related males and one unrelated male competed over females unrelated to all the males. We confirm theoretical expectations that, after controlling for male social status, competition over mating was reduced among related males. However, this effect was contrasted by other sexual selection mechanisms. First, females biased male mating in favor of the unrelated male, and might also favor his inseminations after mating. Second, males invested more—rather than fewer—sperm in postcopulatory competition with relatives. A number of factors may contribute to explain this counterintuitive pattern of sperm allocation, including trade‐offs between male investment in pre‐ versus postcopulatory competition, differences in the relative relatedness of pre‐ versus postcopulatory competitors, and female bias in sperm utilization in response to male relatedness. Collectively, these results reveal that within‐group male relatedness may have contrasting effects in different mechanisms of sexual selection. PMID:27925168

  16. iTRAQ-facilitated proteomic profiling of anthers from a photosensitive male sterile mutant and wild-type cotton (Gossypium hirsutum L.).

    PubMed

    Liu, Ji; Pang, Chaoyou; Wei, Hengling; Song, Meizhen; Meng, Yanyan; Ma, Jianhui; Fan, Shuli; Yu, Shuxun

    2015-08-03

    Male sterility is a common phenomenon in flowering plants, and it has been successfully developed in several crops by taking advantage of heterosis. Cotton (Gossypium hirsutum L.) is an important economic crop, used mainly for the production of textile fiber. Using a space mutation breeding technique, a novel photosensitive genetic male sterile mutant CCRI9106 was isolated from the wild-type upland cotton cultivar CCRI040029. To use CCRI9106 in cotton hybrid breeding, it is of great importance to study the molecular mechanisms of its male sterility. Here, histological and iTRAQ-facilitated proteomic analyses of anthers were performed to explore male sterility mechanisms of the mutant. Scanning and transmission electron microscopy of the anthers showed that the development of pollen wall in CCRI9106 was severely defective with a lack of exine formation. At the protein level, 6121 high-confidence proteins were identified and 325 of them showed differential expression patterns between mutant and wild-type anthers. The proteins up- or down-regulated in MT anthers were mainly involved in exine formation, protein degradation, calcium ion binding,etc. These findings provide valuable information on the proteins involved in anther and pollen development, and contribute to elucidate the mechanism of male sterility in upland cotton.

  17. High-resolution fine mapping of ps-2, a mutated gene conferring functional male sterility in tomato due to non-dehiscent anthers.

    PubMed

    Gorguet, Benoit; Schipper, Danny; van Heusden, Adriaan W; Lindhout, Pim

    2006-11-01

    Functional male sterility is an important trait for the production of hybrid seeds. Among the genes coding for functional male sterility in tomato is the positional sterility gene ps-2. ps-2 is monogenic recessive, confers non-dehiscent anthers and is the most suitable for practical uses. In order to have tools for molecular-assisted selection (MAS) we fine mapped the ps-2 locus. This was done in an F(2) segregating population derived from the interspecific cross between a functionally male sterile line (ps-2/ps-2; Solanum lycopersicum) and a functionally male fertile line (S. pimpinellifolium). Here we report the procedure that has led to the high-resolution fine mapping of the ps-2 locus in a 1.65 cM interval delimited by markers T0958 and T0635 on the short arm of Chromosome 4. The presence of many COS markers in the local high-resolution map allowed us to study the synteny between tomato and Arabidopsis at the ps-2 locus region. No obvious candidate gene for ps-2 was identified among the known functional male sterility genes in Arabidopsis.

  18. 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.

  19. Sexual selection drives evolution and rapid turnover of male gene expression

    PubMed Central

    Harrison, Peter W.; Wright, Alison E.; Zimmer, Fabian; Dean, Rebecca; Montgomery, Stephen H.; Pointer, Marie A.; Mank, Judith E.

    2015-01-01

    The profound and pervasive differences in gene expression observed between males and females, and the unique evolutionary properties of these genes in many species, have led to the widespread assumption that they are the product of sexual selection and sexual conflict. However, we still lack a clear understanding of the connection between sexual selection and transcriptional dimorphism, often termed sex-biased gene expression. Moreover, the relative contribution of sexual selection vs. drift in shaping broad patterns of expression, divergence, and polymorphism remains unknown. To assess the role of sexual selection in shaping these patterns, we assembled transcriptomes from an avian clade representing the full range of sexual dimorphism and sexual selection. We use these species to test the links between sexual selection and sex-biased gene expression evolution in a comparative framework. Through ancestral reconstruction of sex bias, we demonstrate a rapid turnover of sex bias across this clade driven by sexual selection and show it to be primarily the result of expression changes in males. We use phylogenetically controlled comparative methods to demonstrate that phenotypic measures of sexual selection predict the proportion of male-biased but not female-biased gene expression. Although male-biased genes show elevated rates of coding sequence evolution, consistent with previous reports in a range of taxa, there is no association between sexual selection and rates of coding sequence evolution, suggesting that expression changes may be more important than coding sequence in sexual selection. Taken together, our results highlight the power of sexual selection to act on gene expression differences and shape genome evolution. PMID:25831521

  20. Female social response to male sexual harassment in poeciliid fish: a comparison of six species

    PubMed Central

    Dadda, Marco

    2015-01-01

    Sexual harassment is common among poeciliid fish. In some fishes, males show a high frequency of sneak copulation; such sexual activity is costly to the females in terms of foraging efficiency. In mosquitofish (Gambusia holbrooki), when males are present, the distance between females tends to decrease, and this behavior has been interpreted as an adaptive strategy to dilute the costs of male sexual activity. In this study, the tendency to reduce distance in the presence of a male has been investigated in females of six poeciliid species (Girardinus metallicus, Girardinus falcatus, G. holbrooki, Poecilia reticulata, Xiphophorus hellerii, and Xiphophorus mayae) that exhibit different male mating strategies and different levels of sexual activity. Results revealed large interspecific differences in the pattern of female aggregation. Females of species with a high frequency of sneak copulations tended to reduce their social distance in the presence of a male. By contrast, species that rely mainly on courtship showed little or no variation in social distance. The proportion of sneak copulations predicts the degree of variation in female social response, but the amount of total sexual activity does not, suggesting that the change in females' social distance when a male is present may indeed serve to reduce the costs of male sexual harassment. PMID:26483719

  1. Female social response to male sexual harassment in poeciliid fish: a comparison of six species.

    PubMed

    Dadda, Marco

    2015-01-01

    Sexual harassment is common among poeciliid fish. In some fishes, males show a high frequency of sneak copulation; such sexual activity is costly to the females in terms of foraging efficiency. In mosquitofish (Gambusia holbrooki), when males are present, the distance between females tends to decrease, and this behavior has been interpreted as an adaptive strategy to dilute the costs of male sexual activity. In this study, the tendency to reduce distance in the presence of a male has been investigated in females of six poeciliid species (Girardinus metallicus, Girardinus falcatus, G. holbrooki, Poecilia reticulata, Xiphophorus hellerii, and Xiphophorus mayae) that exhibit different male mating strategies and different levels of sexual activity. Results revealed large interspecific differences in the pattern of female aggregation. Females of species with a high frequency of sneak copulations tended to reduce their social distance in the presence of a male. By contrast, species that rely mainly on courtship showed little or no variation in social distance. The proportion of sneak copulations predicts the degree of variation in female social response, but the amount of total sexual activity does not, suggesting that the change in females' social distance when a male is present may indeed serve to reduce the costs of male sexual harassment.

  2. The role of male sexual arousal in rape: six models.

    PubMed

    Barbaree, H E; Marshall, W L

    1991-10-01

    This article examines men's sexual arousal to rape cues and its possible role in sexual assault. The article presents six different models that have been described in the literature to account for men's sexual arousal to descriptions of rape. The models are divided into two broad categories, response control models and stimulus control models, and are further divided into models postulating a "trait" that might distinguish rapists from other men and those postulating a "state" that might be present in men while they commit a sexual assault. A number of the models are supported by empirical data, and some of these data are reviewed. The article suggests that different models may be operating in different men when they commit sexual assault. These models are discussed in relation to the current literature on the classification and diagnosis of sexual offenders.

  3. 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...

  4. 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

    ERIC Educational Resources Information Center

    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…

  5. Relationship between sexual satiety and motivation, brain androgen receptors and testosterone in male mandarin voles.

    PubMed

    He, Fengqin; Yu, Peng; Wu, Ruiyong

    2013-08-01

    Androgen receptors participate in the neuroendocrine regulation of male sexual behavior, primarily in brain areas located in the limbic system. Males of many species present a long-term inhibition of sexual behavior after several ejaculations, known as sexual satiety. It has been shown in rats that androgen receptor expression is reduced 24h after a single ejaculation, or mating to satiety, in the medial preoptic area, nucleus accumbens and ventromedial hypothalamus. The aim of this study was to analyze these processes in another animal, the mandarin vole (Microtus mandarinus). We compared differences in androgen receptor (AR) and testosterone (T) expression in various brain areas between male mandarin voles sexually satiated and those exposed to receptive females but not allowed to mate. Sexual satiety was associated with decreased AR and T expression in the lateral septal nucleus (LS), medial amygdala (MeA), medial preoptic area (mPOA) and ventromedial hypothalamic nucleus (VMH). Males exposed to receptive females showed an increase in AR and T expression in the bed nucleus of the stria terminalis (BNST), LS, MeA and VMH. Serum testosterone levels remained unchanged after 24h in males exposed to receptive females or males mated to satiety. These data suggest a relationship between sexual activity and a decrease in AR and T expression in specific brain areas, and a relationship between sexual motivation and increased AR and T expression in other brain areas, independently of testosterone levels.

  6. Problems in Sexual Functioning among Male OEF/OIF Veterans Seeking Treatment for Posttraumatic Stress

    PubMed Central

    Badour, Christal L.; Gros, Daniel F.; Szafranski, Derek D.; Acierno, Ron

    2015-01-01

    Objective Few studies have examined sexual dysfunction among Operations Enduring/Iraqi Freedom (OEF/OIF) veterans with posttraumatic stress disorder (PTSD). The present study investigated predictors of erectile dysfunction [ED] and self-reported sexual problems among 150 male combat veterans seeking outpatient treatment for PTSD within the Veterans Affairs healthcare system. Method Participants completed clinical interviews and several questionnaires including measures of sexual arousal and sexual desire. A medical records review was also conducted to document evidence of an ED diagnosis or associated medication use. Results An ED diagnosis was present for 12% of the sample, and 10% were taking associated medications. Sexual arousal problems were reported by sixty-two percent of partnered veterans. Sexual desire problems were endorsed by 63% of the total sample, and by 72% of partnered veterans. Age was the only significant predictor of ED diagnosis or medication use. Age, race, PTSD diagnosis (versus subclinical symptoms), depression, and social support predicted self-reported sexual arousal problems; while race, combat exposure, social support, and avoidance/numbing symptoms of PTSD predicted self-reported sexual desire problems. Conclusions Sexual problems are common among male OEF/OIF combat veterans seeking treatment for PTSD. Moreover, avoidance/numbing symptoms robustly predicted sexual desire problems. These findings highlight the importance of expanding assessment of sexual dysfunction and support the need for additional research in this area. PMID:25596624

  7. The Effect of Amantadine on Clomipramine Induced Sexual Dysfunction in Male Rats

    PubMed Central

    Devaangam, Sheshadri Shekar; Kumar, Ashok

    2011-01-01

    Objective Several studies have reported that Clomipramine has the ability to suppress male rat sexual behavior. Literature indicates that the activation of brain D2 receptors causes facilitation of penile erection, and a number of reports have indicated dopamine’s involvement in sexual function. Hence this study was undertaken to investigate the effect of Amantadine, a dopamine agonists on the Clomipramine induced sexual dysfunction. Methods The study subjects involved a total of 48 males and 48 females, 4 months old Sprague-Dawley albino rats, all housed in a group of six males and females separately in plexi glass cages in an acclimatized colony room (25±0.50C) maintained on a 12/12 hr light/dark cycle. The male rats were randomly divided into four groups of 12 male rats each. Group I served as controls. Group II, III, and IV were treated with Amantadine (9 mg/kg body weight, p.o) 30 min, prior to the treatment with 13.5 mg/kg, 27 mg/Kg and 54 mg/Kg bodyweight p.o of Clomipramine respectively for 60 days. The control group received vehicle 1 ml / kg p.o. The sexual behavior of the male rats was observed to determine the following parameters: mount latency, intromission latency, ejaculation latency, post ejaculatory pause, and intromission frequency. As well as the sexual behavior; serum testosterone and histopathology of the testes were also investigated in this study. Results The results indicate that Amantadine in all aspects failed to antagonize Clomipramine induced sexual dysfunction in male rats. Even the sexual competence of male rats treated with ½ therapeutic dose (TD) of Clomipramine failed to regain their sexual competence in the presence of Amantadine. Testicular damage and decline in testosterone levels continued in the presence of Amantadine. Conclusion Overall, the results suggest that Amantadine could not be a safe antidote to antagonize Clomipramine induced sexual dysfunction. PMID:22253948

  8. Male adaptations to minimize sexual cannibalism during reproduction in the funnel-web spider Hololena curta.

    PubMed

    Xiao, Yong-Hong; Zunic-Kosi, Alenka; Zhang, Long-Wa; Prentice, Thomas R; McElfresh, J Steven; Chinta, Satya P; Zou, Yun-Fan; Millar, Jocelyn G

    2015-12-01

    Males of many spider species risk being attacked and cannibalized while searching for, courting, and mating with conspecific females. However, there are exceptions. We show that the funnel-web spider, Hololena curta, has 3 adaptations that minimize risk to males during courtship and mating, and enhance reproductive success. First, males detected chemical or tactile signals associated with webs of virgin females, and differentiated them from webs of mated females, enabling males to increase encounter rates with virgin females and avoid aggressive mated females. Second, males produced stereotyped vibrational signals during courting which induced female quiescence and suppressed female aggression. Third, when touched by males, sexually receptive females entered a cataleptic state, allowing males to safely approach and copulate. Because males can mate multiple times and the sex ratio in natural populations of H. curta is female biased, overall reproductive output is likely increased by males of this species avoiding sexual cannibalism.

  9. Theoretical perspectives of male sexual abuse: conceptualization of a case study.

    PubMed

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

    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 abuse can have on the development of a young boy. These perspectives include early family relationships and attachment theory, developmental psychopathology, and trauma theory. These theoretical lenses provide a conceptual understanding into why some victims are vulnerable to the effects of sexual abuse. Each theoretical view is applied to a case study of an adolescent male with a history of early trauma and sexual abuse. Clinical implications are discussed.

  10. Serotonin 1A receptors and sexual behavior in male rats: a review.

    PubMed

    Snoeren, Eelke M S; Veening, Jan G; Olivier, Berend; Oosting, Ronald S

    2014-06-01

    Serotonin plays an important role in male sexual behavior. Many studies have been performed on the pivotal role of 5-HT₁A receptors in sexual behavior. Overall, 5-HT₁A receptors do not appear to be involved under normal circumstances, but become very important under conditions of elevated serotonin levels in sexual behavior. 5-HT₁A receptor agonists facilitate ejaculatory behavior in male rats, while inhibiting copulatory behavior. Three different phases can be distinguished in rats' sexual cycle, the introductory (precopulatory), the copulatory and the executive (ejaculatory) phases. Different mechanisms and brain regions are involved in these phases. The mechanisms, brain regions and the possible involvement of 5-HT and 5-HT₁A receptors in the appropriate phases in male rat sexual behavior will be discussed in the current review.

  11. Sexual victimization in female and male college students: examining the roles of alcohol use, alcohol expectancies, and sexual sensation seeking.

    PubMed

    Monks, Stormy M; Tomaka, Joe; Palacios, Rebecca; Thompson, Sharon E

    2010-11-01

    Alcohol and alcohol expectancies relate to sexual victimization. The present study examined these links in a sample of 407 predominantly Hispanic male and female college students, along the Mexico-US border. The study also examined the independent contribution of sexual sensation seeking to the prediction of victimization. Results showed that victimization was associated with alcohol risk, alcohol consumption-related problems, and positive alcohol expectancies. Importantly, sexual sensation seeking independently predicted victimization and did so after controlling for alcohol risk and expectancies. Our results suggest that associations among victimization, alcohol risk, and expectancies generalize to Hispanic women and men. The study's limitations are noted.

  12. Female-female mounting among goats stimulates sexual performance in males.

    PubMed

    Shearer, Meagan K; Katz, Larry S

    2006-06-01

    The hypothesis that female-female mounting is proceptivity in goats, in that male goats are aroused by the visual cues of this mounting behavior, was tested. Once a week, male goats were randomly selected and placed in a test pen in which they were allowed to observe one of six selected social or sexual stimulus conditions. The stimulus conditions were one familiar male with two estrous females (MEE); three estrous females that displayed female-female mounting (E(m)); three estrous females that did not mount (E(nm)); three non-estrous females (N(E)); three familiar males (M); and no animals in the pen (Empty). After 10 min, the stimulus animals were removed, and an estrous female was placed in the test pen with the male for a 20-min sexual performance test. During sexual performance tests, the frequencies and latencies of all sexual behaviors were recorded. This procedure was repeated so all males (n = 6) were tested once each test day, and all the stimulus conditions were presented each test day. This was repeated weekly until all males had been exposed to each stimulus condition. Viewing mounting behavior, whether male-female or female-female, increased the total number of sexual behaviors displayed, increased ejaculation frequency, and decreased latency to first mount and ejaculation, post-ejaculatory interval, and the interval between ejaculations. We conclude that male goats are aroused by the visual cues of mounting behavior, and that female-female mounting is proceptivity in goats.

  13. [Isolation and identification of specific sequences correlated to cytoplasmic male sterility and fertile maintenance in cauliflower (Brassica oleracea var. botrytis)].

    PubMed

    Wang, Chun Guo; Chen, Xiao Qiang; Li, Hui; Zhao, Qian Cheng; Sun, De Ling; Song, Wen Qin

    2008-02-01

    Analysis of ISSR (Inter-Simple Sequence Repeat) and DDRT-PCR (Differential Display Reverse Transcriptase Polymerase Chain Reaction) was performed between cytoplasmic male sterility cauliflower ogura-A and its corresponding maintainer line ogura-B. Totally, 306 detectable bands were obtained by ISSR using thirty oligonucleotide primers. Commonly, six to twelve bands were produced per primer. Among all these primers only the amplification of primer ISSR3 was polymorphic, an 1100 bp specific band was only detected in maintainer line, named ISSR3(1100). Analysis of this sequence indicated that ISSR3(1100) was high homologous with the corresponding sequences of mitochondrial genome in Brassica napus and Arabidopsis thaliana,which suggested that ISSR3(1100) may derive from mitochondrial genome in cauliflower. To carry out DDRT-PCR analysis, three anchor primers and fifteen random primers were selected to combine. Totally, 1122 bands from 1 000 bp to 50 bp were detected. However, only four bands, named ogura-A 205, ogura-A383, ogura-B307 and ogura-B352, were confirmed to be different display in both lines. This result was further identified by reverse Northern dot blotting analysis. Among these four bands, ogura-A205 and ogura-A383 only express in cytoplasmic male sterility line, while ogura-B307 and ogura-B352 were only detected in maintainer line. Analysis of these sequences indicated that it was the first time that these four sequences were reported in cauliflower. Interestingly, ogura-A205 and ogura-B307 did not exhibit any similarities to other reported sequences in other species, more investigations were required to obtain further information. ogura-A383 and ogura-B352 were also two new sequences, they showed high similarities to corresponding chloroplast sequences of Arabidopsis thaliana and Brassica rapa subsp. pekinensis. So we speculated that these two sequences may derive from chloroplast genome. All these results obtained in this study offer new and

  14. Coy Males and Seductive Females in the Sexually Cannibalistic Colonial Spider, Cyrtophora citricola

    PubMed Central

    Yip, Eric C.; Berner-Aharon, Na’ama; Smith, Deborah R.; Lubin, Yael

    2016-01-01

    The abundance of sperm relative to eggs selects for males that maximize their number of mates and for females that choose high quality males. However, in many species, males exercise mate choice, even when they invest little in their offspring. Sexual cannibalism may promote male choosiness by limiting the number of females a male can inseminate and by biasing the sex ratio toward females because, while females can reenter the mating pool, cannibalized males cannot. These effects may be insufficient for male choosiness to evolve, however, if males face low sequential encounter rates with females. We hypothesized that sexual cannibalism should facilitate the evolution of male choosiness in group living species because a male is likely to encounter multiple receptive females simultaneously. We tested this hypothesis in a colonial orb-weaving spider, Cyrtophora citricola, with a high rate of sexual cannibalism. We tested whether mated females would mate with multiple males, and thereby shift the operational sex ratio toward females. We also investigated whether either sex chooses mates based on nutritional state and age, and whether males choose females based on reproductive state. We found that females are readily polyandrous and exhibit no mate choice related to male feeding or age. Males courted more often when the male was older and the female was younger, and males copulated more often with well-fed females. The data show that males are choosier than females for the traits we measured, supporting our hypothesis that group living and sexual cannibalism may together promote the evolution of male mate choice. PMID:27249787

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

    PubMed

    von Kohn, Christopher; Kiełkowska, Agnieszka; Havey, Michael J

    2013-12-01

    Male-sterile (S) cytoplasm of onion is an alien cytoplasm introgressed into onion in antiquity and is widely used for hybrid seed production. Owing to the biennial generation time of onion, classical crossing takes at least 4 years to classify cytoplasms as S or normal (N) male-fertile. Molecular markers in the organellar DNAs that distinguish N and S cytoplasms are useful to reduce the time required to classify onion cytoplasms. In this research, we completed next-generation sequencing of the chloroplast DNAs of N- and S-cytoplasmic onions; we assembled and annotated the genomes in addition to identifying polymorphisms that distinguish these cytoplasms. The sizes (153 538 and 153 355 base pairs) and GC contents (36.8%) were very similar for the chloroplast DNAs of N and S cytoplasms, respectively, as expected given their close phylogenetic relationship. The size difference was primarily due to small indels in intergenic regions and a deletion in the accD gene of N-cytoplasmic onion. The structures of the onion chloroplast DNAs were similar to those of most land plants with large and small single copy regions separated by inverted repeats. Twenty-eight single nucleotide polymorphisms, two polymorphic restriction-enzyme sites, and one indel distributed across 20 chloroplast genes in the large and small single copy regions were selected and validated using diverse onion populations previously classified as N or S cytoplasmic using restriction fragment length polymorphisms. Although cytoplasmic male sterility is likely associated with the mitochondrial DNA, maternal transmission of the mitochondrial and chloroplast DNAs allows for polymorphisms in either genome to be useful for classifying onion cytoplasms to aid the development of hybrid onion cultivars.

  16. Syndemics and gender affirmation: HIV sexual risk in female-to-male trans masculine adults reporting sexual contact with cisgender males.

    PubMed

    Reisner, Sari L; White Hughto, Jaclyn M; Pardee, Dana; Sevelius, Jae

    2016-10-01

    Female-to-male trans masculine adults who have sex with cisgender (non-transgender) males (TMSM) represent an understudied population in relation to HIV/sexually transmitted infection (STI) risk. This study examined the role of syndemic conditions and social gender affirmation processes (living full-time in one's identified gender) in potentiating sexual risk among TMSM adults in Massachusetts, US. Cross-sectional data were restricted to TMSM who reported lifetime sexual behaviour with a cisgender male (n = 173; mean age = 29.4, SD = 9.6; 18.5% people of colour; 93.1% non-heterosexual identity; 56.1% hormones/surgery). Sexual risk outcomes were: lifetime STI diagnoses, three or more sexual partners in the previous six months, and condomless anal/vaginal sex at last encounter with a cisgender male. Age- and survey mode-adjusted logistic regression models regressed sexual risk outcomes on the main effect of syndemics (six indicators summed: binge drinking, substance use, depression, anxiety, childhood abuse, intimate partner violence), followed by the interaction of syndemics and social gender affirmation. Syndemics were associated with increased odds of all sexual risk indicators (adjusted odds ratios [aORs] = 1.32-1.55; p < 0.0001). Social gender affirmation moderated the association between syndemics and condomless anal/vaginal sex at last encounter with a cisgender male (p < 0.0001). Syndemics were associated with sexual risk in TMSM who had socially affirmed their gender (aOR = 1.79; 95% CI = 1.42-2.25; p < 0.001), but not among those TMSM who had not (aOR = 0.86; 95% CI = 0.63-1.19; p = 0.37). Findings suggest that syndemic pathways to sexual risk are similar for TMSM who have socially gender affirmed as for cisgender MSM. Integration of syndemics and gender affirmation frameworks is recommended in interventions to address TMSM sexual risk.

  17. Factors Related to Childhood Sexual Abuse among Gay/Bisexual Male Internet Escorts

    ERIC Educational Resources Information Center

    Parsons, Jeffrey T.; Bimbi, David S.; Koken, Juline A.; Halkitis, Perry N.

    2005-01-01

    This exploratory investigation examined the relationship between childhood sexual abuse (CSA) and related psychosocial characteristics and sexual behaviors among 46 gay/bisexual male escorts who advertise via the Internet. More than a quarter of men (28.3%) reported some history of CSA. Men reporting CSA were more likely to be from an ethnic…

  18. Coercive Sexual Experiences, Protective Behavioral Strategies, Alcohol Expectancies and Consumption among Male and Female College Students

    ERIC Educational Resources Information Center

    Palmer, Rebekka S.; McMahon, Thomas J.; Rounsaville, Bruce J.; Ball, Samuel A.

    2010-01-01

    Alcohol use and sexual assault on college campuses are highly prevalent and the focus of numerous prevention and intervention efforts. Our goals were to gain a greater understanding of the relationship between coercive sexual experiences, utilization of protective behavioral strategies and alcohol expectancies and consumption among male and female…

  19. 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…

  20. 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…

  1. 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.

  2. Female burying beetles benefit from male desertion: sexual conflict and counter-adaptation over parental investment.

    PubMed

    Boncoraglio, Giuseppe; Kilner, Rebecca M

    2012-01-01

    Sexual conflict drives the coevolution of sexually antagonistic traits, such that an adaptation in one sex selects an opposing coevolutionary response from the other. Although many adaptations and counteradaptations have been identified in sexual conflict over mating interactions, few are known for sexual conflict over parental investment. Here we investigate a possible coevolutionary sequence triggered by mate desertion in the burying beetle Nicrophorus vespilloides, where males commonly leave before their offspring reach independence. Rather than suffer fitness costs as a consequence, our data suggest that females rely on the male's absence to recoup some of the costs of larval care, presumably because they are then free to feed themselves on the carcass employed for breeding. Consequently, forcing males to stay until the larvae disperse reduces components of female fitness to a greater extent than caring for young singlehandedly. Therefore we suggest that females may have co-evolved to anticipate desertion by their partners so that they now benefit from the male's absence.

  3. 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...

  4. Investigation of the mechanism for phthalate-induced toxicity during male sexual differentiation in the rat

    EPA Science Inventory

    Male rats exposed to phthalate esters during sexual differentiation (GDI4-GDI8) display various developmental abnormalities of the reproductive tract that are manifested later in adult life. Induction of these malformations is associated with declines in fetal testicular testoste...

  5. What motivates the sexual double standard? More support for male versus female control theory.

    PubMed

    Rudman, Laurie A; Fetterolf, Janell C; Sanchez, Diana T

    2013-02-01

    The present research uniquely compared male control theory (MCT) versus female control theory (FCT) to illuminate motives for the sexual double standard (SDS), whereby men gain status from engaging in casual sex or having many sexual partners, but women are stigmatized for it. Consistent with MCT, men were more likely than women to endorse the SDS and to give sexual advice in ways that reinforce it-gender differences that were mediated by hostile sexism (HS) and endorsing the SDS, respectively. The data did not support FCT's argument that women are motivated by sexual economics to restrict female sexuality (Baumeister & Twenge, 2002). Both genders discouraged women from having casual sex to protect women from social stigma and rape myths that justify violence against sexual women. In concert, the findings support MCT more than FCT and suggest that sexism, stigma, and rape myths are primary obstacles to sexual equality.

  6. The effect of oral medroxyprogesterone acetate and methyltestosterone on sexual functioning in a male contraceptive trial.

    PubMed

    Doody, K; Bain, J

    1985-01-01

    Twenty-three men who participated in a 15-month clinical trial to assess the potential effectiveness of using a combination of varying doses of medroxyprogesterone acetate (MPA) and methyltestosterone (MT) as a male contraceptive agent, completed a "sexual problem checklist" every two weeks. The study was divided into three phases: pre-treatment (3 months), treatment (6 months), post-treatment (6 months). The questionnaire evaluated changes in various aspects of sexual behaviour and sexual perception and explored whether the treatment influenced any of the parameters considered. The results indicated a small, but significant, decrease in subjective assessment of sexual drive. This was not, however, accompanied by a change in sexual behaviour, in that subjects experienced the same number of erections, ejaculations and frequency of intercourse. It is concluded that the combination of MPA and MT in the doses used may produce a slight decrease in subjective assessment of sexual drive, but no change in actual sexual behaviour.

  7. Excitotoxic lesions of the nucleus paragigantocellularis facilitate male sexual behavior but attenuate female sexual behavior in rats.

    PubMed

    Normandin, J J; Murphy, A Z

    2011-02-23

    Little is known regarding the descending inhibitory control of genital reflexes such as ejaculation and vaginal contractions. The brainstem nucleus paragigantocellularis (nPGi) projects bilaterally to the lumbosacral motoneuron pools that innervate the genital musculature of both male and female rats. Electrolytic nPGi lesions facilitate ejaculation in males, leading to the hypothesis that the nPGi is the source of descending inhibition to genital reflexes. However, the function of the nPGi in female sexual behavior remains to be elucidated. To this end, male and female rats received bilateral excitotoxic fiber-sparing lesions of the nPGi, and sexual behavior and sexual behavior-induced Fos expression were examined. In males, nPGi lesions facilitated copulation, supporting the hypothesis that the nPGi, and not fibers-of-passage, is the source of descending inhibition of genital reflexes in male rats. nPGi lesions in males did not alter sexual behavior-induced Fos expression in any brain region examined. nPGi-lesioned females spent significantly less time mating with stimulus males and had significantly longer ejaculation-return latencies compared to baseline. These results did not significantly differ from control females, but this trend warranted further analysis of the reinforcing value of sexual behavior. Both lesioned and non-lesioned females formed a conditioned place preference (CPP) for artificial vaginocervical stimulation (aVCS). However, post-reinforcement, nPGi-lesioned females did not differ in the percentage of time spent in the non-reinforced chamber versus the reinforced chamber, suggesting a weakened CPP for aVCS. nPGi lesions in females reduced sexual behavior-induced Fos expression throughout the hypothalamus and amygdala. Taken together, these results suggest that while nPGi lesions in males facilitate copulation, such lesions in females attenuate several aspects of sexual behavior resulting in a reduction in the rewarding value of copulation

  8. Cytomixis and meiotic abnormalities during microsporogenesis are responsible for male sterility and chromosome variations in Houttuynia cordata.

    PubMed

    Guan, J-Z; Wang, J-J; Cheng, Z-H; Liu, Y; Li, Z-Y

    2012-01-17

    Houttuynia cordata (Saururaceae) is a leaf vegetable and a medicinal herb througout much of Asia. Cytomixis and meiotic abnormalities during microsporogenesis were found in two populations of H. cordata with different ploidy levels (2n = 38, 96). Cytomixis occurred in pollen mother cells during meiosis at high frequencies and with variable degrees of chromatin/chromosome transfer. Meiotic abnormalities, such as chromosome laggards, asymmetric segregation and polyads, also prevailed in pollen mother cells at metaphase of the first division and later stages. They were caused by cytomixis and resulted in very low pollen viability and male sterility. Pollen mother cells from the population with 2n = 38 showed only simultaneous cytokinesis, but most pollen mother cells from the population with 2n = 96 showed successive cytokinesis; a minority underwent simultaneous cytokinesis. Cytomixis and irregular meiotic divisions appear to be the origin of the intraspecific polyploidy in this species, which has large variations in chromosome numbers.

  9. Female preferences drive the evolution of mimetic accuracy in male sexual displays.

    PubMed

    Coleman, Seth William; Patricelli, Gail Lisa; Coyle, Brian; Siani, Jennifer; Borgia, Gerald

    2007-10-22

    Males in many bird species mimic the vocalizations of other species during sexual displays, but the evolutionary and functional significance of interspecific vocal mimicry is unclear. Here we use spectrographic cross-correlation to compare mimetic calls produced by male satin bowerbirds (Ptilonorhynchus violaceus) in courtship with calls from several model species. We show that the accuracy of vocal mimicry and the number of model species mimicked are both independently related to male mating success. Multivariate analyses revealed that these mimetic traits were better predictors of male mating success than other male display traits previously shown to be important for male mating success. We suggest that preference-driven mimetic accuracy may be a widespread occurrence, and that mimetic accuracy may provide females with important information about male quality. Our findings support an alternative hypothesis to help explain a common element of male sexual displays.

  10. Transcriptomic Analysis Reveals New Insights into High-Temperature-Dependent Glume-Unclosing in an Elite Rice Male Sterile Line

    PubMed Central

    Fu, Chongyun; Wang, Feng; Liu, Wuge; Liu, Dilin; Li, Jinhua; Zhu, Manshan; Liao, Yilong; Liu, Zhenrong; Huang, Huijun; Zeng, Xueqin; Ma, Xiaozhi

    2017-01-01

    Glume-unclosing after anthesis is a widespread phenomenon in hybrid rice and also a maternal hereditary trait. The character of Glume-unclosing in rice male sterile lines also seriously influences germination rate and the commercial quality of hybrid rice seeds. We validated that the type of glume-unclosing after anthesis in the elite rice thermo-sensitive genic male sterile (TGMS) line RGD-7S was caused by high temperature. Transcriptomic sequencing of rice panicles was performed to explore the change of transcript profiles under four conditions: pre- and post-anthesis under high temperature (HRGD0 and HRGD1), and pre- and post-anthesis under low temperature (LRGD0 and LRGD1). We identified a total of 14,540 differentially expressed genes (DEGs) including some heat shock factors (HSFs) across the four samples. We found that more genes were up-regulated than down-regulated in the sample pair HRGD1vsHRGD0. These up-regulated genes were significantly enriched in the three biological processes of carbohydrate metabolism, response to water and cell wall macromolecular metabolism. Simultaneously, we also found that the HSF gene OsHsfB1 was specially up-regulated in HRGD1vsHRGD0. However, the down-regulated DEGs in LRGD1vsLRGD0 were remarkably clustered in the biological process of carbohydrate metabolism. This suggests that carbohydrate metabolism may play a key role in regulation of glume-unclosing under high temperature in RGD-7S. We also analyzed the expression pattern of genes enriched in carbohydrate metabolism and several HSF genes under different conditions and provide new insights into the cause of rice glume-unclosing. PMID:28261226

  11. Acceptability of Voluntary Medical Male Circumcision (VMMC) among Male Sexually Transmitted Diseases Patients (MSTDP) in China

    PubMed Central

    Lau, Joseph T. F.; Kim, Yoona

    2016-01-01

    Voluntary Medical Male circumcision (VMMC) is an evidence-based, yet under-utilized biomedical HIV intervention in China. No study has investigated acceptability of VMMC among male sexually transmitted diseases patients (MSTDP) who are at high risk of HIV transmission. A cross-sectional survey interviewed 350 HIV negative heterosexual MSTDP in Shenzhen, China; 12.0% (n = 42) of them were circumcised at the time of survey. When the uncircumcised participants (n = 308) were informed that VMMC could reduce the risk of HIV infection via heterosexual intercourse by 50%, the prevalence of acceptability of VMMC in the next six months was 46.1%. Adjusted for significant background variables, significant factors of acceptability of VMMC included: 1) emotional variables: the Emotional Representation Subscale (adjusted odds ratios, AOR = 1.13, 95%CI: 1.06–1.18), 2) cognitive variables derived from Health Belief Model (HBM): perceived some chance of having sex with HIV positive women in the next 12 months (AOR = 2.48, 95%CI: 1.15–5.33) (perceived susceptibility), perceived severity of STD infection (AOR = 1.06, 95%CI: 1.02–1.10), perceived benefit of VMMC in risk reduction (AOR = 1.29, 95%CI: 1.16–1.42) and sexual performance (AOR = 1.45, 95%CI: 1.26–1.71), perceived barriers against taking up VMMC (AOR = 0.88, 95%CI: 0.81–0.95), and perceived cue to action (AOR = 1.41, 95%CI: 1.23–1.61) and self-efficacy (AOR = 1.38, 95%CI: 1.26–1.35) related to taking up VMMC. The association between perceived severity of STD infection and acceptability was fully mediated by emotional representation of STD infection. The relatively low prevalence of circumcision and high acceptability suggested that the situation was favorable for implementing VMMC as a means of HIV intervention among MSTDP in China. HBM is a potential suitable framework to guide the design of future VMMC promotion. Future implementation programs should be conducted in STD clinic settings, taking the

  12. A selective androgen receptor modulator enhances male-directed sexual preference, proceptive behavior, and lordosis behavior in sexually experienced, but not sexually naive, female rats.

    PubMed

    Kudwa, A E; López, F J; McGivern, R F; Handa, R J

    2010-06-01

    Androgens influence many aspects of reproductive behavior, including sexual preference of females for males. In oophorectomized women with sexual desire disorder, testosterone patches improve libido, but their use is limited because of adverse side effects. Selective androgen receptor modulators offer an improved safety profile for both sexes: enhancing libido and muscle and bone growth in a manner similar to steroidal androgens but with fewer adverse effects, such as hirsutism, acne, and prostate growth. The current study investigated the action of a novel selective androgen receptor modulator (LGD-3303 [9-chloro-2-ethyl-1-methyl-3-(2,2,2-trifluoroethyl)-3H-pyrrolo-[3,2-f]quinolin-7(6H)-one]) on male-directed sexual preference, proceptivity, and lordosis behavior of female rats. LGD-3303 is a nonsteroidal, nonaromatizable, highly selective ligand for the androgen receptor and effectively crosses the blood-brain barrier. Gonadectomized female rats were treated with LGD-3303 (3-30 mg/kg) or vehicle by daily oral gavage. Results showed that LGD-3303 treatment enhanced sexual preference of females for males but only if females had previous sexual experience. This occurred after 1 or 7 d of treatment. In contrast, preference for males was inhibited by LGD-3303 treatments of sexually naive females. The LGD-3303 increase in male preference was blocked by pretreatment with the androgen receptor antagonist flutamide. LGD-3303 treatment increased lordosis and proceptivity behaviors in ovariectomized females primed with suboptimal doses of estradiol benzoate plus progesterone. These data support the concept that LGD-3303 can stimulate aspects of female sexual behavior and may serve as a potential therapeutic for women with sexual desire disorders.

  13. Relationship between male sterility and β-1,3-glucanase activity and callose deposition-related gene expression in wheat (Triticum aestivum L.).

    PubMed

    Liu, H Z; Zhang, G S; Zhu, W W; Ba, Q S; Niu, N; Wang, J W; Ma, S C; Wang, J S

    2015-01-26

    In previous studies, we first isolated one different protein β-1,3-glucanase using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry from normal wheat (Triticum aestivum L.) and chemical hybridization agent-induced male sterility (CIMS) wheat. In this experiment, β-1,3-glucanase activity and the expression of a callose deposition-related gene, UDP-glucose phosphorylase (UGPase), were determinate in normal, CIMS, and genetic male sterility (GS) wheat. β-1,3-glucanase activity was significantly different between the fertile and sterile lines during callose synthesis and degradation, but there was no difference between CIMS and GS wheat. The UGPase gene of callose deposition was highly expressed in the meiophase and sharply decreased in the tetrad stage. However, the expression of the UGPase gene was significantly different between the fertile and sterile lines. These data indicated that β-1,3-glucanase activity and the expression of the UGPase gene play important roles in the male sterility of wheat. Consequently, pollen mother cells (PMCs) might degenerate at the early meiosis stage, and differences in UGPase gene expression and β-1,3-glucanase activity might eventually result in complete pollen collapse. In addition, the critical period of anther abortion might be the meiosis stage to the tetrad stage rather than what we previously thought, the mononuclear period.

  14. Specific down-regulation of spermatogenesis genes targeted by 22G RNAs in hybrid sterile males associated with an X-Chromosome introgression.

    PubMed

    Li, Runsheng; Ren, Xiaoliang; Bi, Yu; Ho, Vincy Wing Sze; Hsieh, Chia-Ling; Young, Amanda; Zhang, Zhihong; Lin, Tingting; Zhao, Yanmei; Miao, Long; Sarkies, Peter; Zhao, Zhongying

    2016-09-01

    Hybrid incompatibility (HI) prevents gene flow between species, thus lying at the heart of speciation genetics. One of the most common HIs is male sterility. Two superficially contradictory observations exist for hybrid male sterility. First, an introgression on the X Chromosome is more likely to produce male sterility than on autosome (so-called large-X theory); second, spermatogenesis genes are enriched on the autosomes but depleted on the X Chromosome (demasculinization of X Chromosome). Analysis of gene expression in Drosophila hybrids suggests a genetic interaction between the X Chromosome and autosomes that is essential for male fertility. However, the prevalence of such an interaction and its underlying mechanism remain largely unknown. Here we examine the interaction in nematode species by contrasting the expression of both coding genes and transposable elements (TEs) between hybrid sterile males and its parental nematode males. We use two lines of hybrid sterile males, each carrying an independent introgression fragment from Caenorhabditis briggsae X Chromosome in an otherwise Caenorhabditis nigoni background, which demonstrate similar defects in spermatogenesis. We observe a similar pattern of down-regulated genes that are specific for spermatogenesis between the two hybrids. Importantly, the down-regulated genes caused by the X Chromosome introgressions show a significant enrichment on the autosomes, supporting an epistatic interaction between the X Chromosome and autosomes. We investigate the underlying mechanism of the interaction by measuring small RNAs and find that a subset of 22G RNAs specifically targeting the down-regulated spermatogenesis genes is significantly up-regulated in hybrids, suggesting that perturbation of small RNA-mediated regulation may contribute to the X-autosome interaction.

  15. Specific down-regulation of spermatogenesis genes targeted by 22G RNAs in hybrid sterile males associated with an X-Chromosome introgression

    PubMed Central

    Li, Runsheng; Ren, Xiaoliang; Bi, Yu; Ho, Vincy Wing Sze; Hsieh, Chia-Ling; Young, Amanda; Zhang, Zhihong; Lin, Tingting; Zhao, Yanmei; Miao, Long; Sarkies, Peter

    2016-01-01

    Hybrid incompatibility (HI) prevents gene flow between species, thus lying at the heart of speciation genetics. One of the most common HIs is male sterility. Two superficially contradictory observations exist for hybrid male sterility. First, an introgression on the X Chromosome is more likely to produce male sterility than on autosome (so-called large-X theory); second, spermatogenesis genes are enriched on the autosomes but depleted on the X Chromosome (demasculinization of X Chromosome). Analysis of gene expression in Drosophila hybrids suggests a genetic interaction between the X Chromosome and autosomes that is essential for male fertility. However, the prevalence of such an interaction and its underlying mechanism remain largely unknown. Here we examine the interaction in nematode species by contrasting the expression of both coding genes and transposable elements (TEs) between hybrid sterile males and its parental nematode males. We use two lines of hybrid sterile males, each carrying an independent introgression fragment from Caenorhabditis briggsae X Chromosome in an otherwise Caenorhabditis nigoni background, which demonstrate similar defects in spermatogenesis. We observe a similar pattern of down-regulated genes that are specific for spermatogenesis between the two hybrids. Importantly, the down-regulated genes caused by the X Chromosome introgressions show a significant enrichment on the autosomes, supporting an epistatic interaction between the X Chromosome and autosomes. We investigate the underlying mechanism of the interaction by measuring small RNAs and find that a subset of 22G RNAs specifically targeting the down-regulated spermatogenesis genes is significantly up-regulated in hybrids, suggesting that perturbation of small RNA-mediated regulation may contribute to the X-autosome interaction. PMID:27197225

  16. Sexual Violence Against Female and Male Children in the United Republic of Tanzania.

    PubMed

    Vagi, Kevin J; Brookmeyer, Kathryn A; Gladden, R Matthew; Chiang, Laura F; Brooks, Andrew; Nyunt, Myo-Zin; Kwesigabo, Gideon; Mercy, James A; Dahlberg, Linda L

    2016-03-14

    During a household survey in Tanzania, a nationally representative sample of females and males aged 13-24 years reported any experiences of sexual violence that occurred before the age of 18 years. The authors explore the prevalence, circumstances, and health outcomes associated with childhood sexual violence. The results suggest that violence against children in Tanzania is pervasive, with roughly three in 10 females and one in eight males experiencing some form of childhood sexual violence, and its health consequences are severe. Results are being used by the Tanzanian government to implement a National Plan of Action.

  17. 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.

  18. Effects of pre-irradiation conditioning of Medfly pupae (Diptera: Tephritidae): Hypoxia and quality of sterile males

    SciTech Connect

    Nestel, D.; Nemny-Lavy, E.; Islam, S.M.; Wornoayporn, V.; Caceres, C.

    2007-03-15

    Irradiation of pupae in sterile insect technique (SIT) projects is usually undertaken in hypoxic atmospheres, which have been shown to lessen the deleterious effects of irradiation on the quality of adult sterile flies. Although this is the accepted technology in most mass-rearing and sterilization facilities, to date no information has been generated on the actual levels of oxygen (O{sub 2}) in pupae-packing containers during irradiation. The present study utilized recently-developed technology to investigate the O{sub 2} level inside bags in which pupae of Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) are packed prior to irradiation, the ability of pupae to create hypoxic environments in these bags, and the effect of O{sub 2} atmospheres on the quality of irradiated males. Pupae, 1 d before adult emergence, were shown to deplete the O{sub 2} level in sealed bags in approximately 1 h. The rate of O{sub 2} consumption was dependent upon pupal age and incubation temperature. Incubation temperature did not significantly affect the quality of pupae or mating capacity of resultant adult males if pupae were irradiated under maximal hypoxic conditions inside packing bags. In contrast, mating competitiveness drastically decreased when pupae were irradiated under ambient O{sub 2} conditions, with the packing bag open. There was no difference in the mating capacity of males when pupae were irradiated in sealed bags under either 10% or 2% O{sub 2} levels, or under maximal hypoxia. Normal doses of fluorescent dye, applied to pupae to mark sterile flies, did not affect the ability of pupae to create hypoxic conditions inside packing bags, nor the quality control parameters of either pupae or adults. Current practices in mass-rearing facilities are discussed in the light of these results. (author) [Spanish] La irradiacion de pupas en proyectos de mosca esteril usualmente se hace bajo condiciones de hipoxia. Esta condicion ha demostrado ser menos detrimente a

  19. Measuring Implicit Sexual Response Biases to Nude Male and Female Pictures in Androphilic and Gynephilic Men.

    PubMed

    Timmins, Liam; Barnes-Holmes, Dermot; Cullen, Claire

    2016-05-01

    Snowden, Wichter, and Gray (2008) demonstrated that an Implicit Association Test and a Priming Task both predicted the sexual orientation of gynephilic and androphilic men in terms of their attraction biases towards pictures of nude males and females. For both measures, relative bias scores were obtained, with no information on the separate response biases to each target gender. The present study sought to extend this research by assessing both relative and individual implicit biases using the Implicit Relational Assessment Procedure (IRAP). An explicit measure screened for men with androphilic (n = 16) or gynephilic (n = 16) orientations on the dimensions of "sexual attraction," "sexual behavior," "sexual fantasies," "hetero/gay lifestyle," and "self identification." The IRAP involved responding "True" or "False" to pictures of nude males and females as either attractive or unattractive. Participants were required to respond in a manner consistent with their reported sexual orientation for half of the IRAP's test blocks and inconsistent for the other half. Response latencies were recorded and analyzed. The IRAP revealed a non-orthogonal pattern of biases across the two groups and had an excellent ability to predict sexual orientation with areas under the curves of 1.0 for the relative bias score and .94 and .95 for the bias scores for the male and female pictures, respectively. Correlations between the IRAP and explicit measures of sexual orientation were consistently high. The findings support the IRAP as a potentially valuable tool in the study of sexual preferences.

  20. The frequency of sexual dysfunctions in male partners of women with vaginismus in a Turkish sample.

    PubMed

    Dogan, S; Dogan, M

    2008-01-01

    The aim of this investigation is to determine the sexual history traits, sexual satisfaction level and frequency of sexual dysfunctions in men whose partners have vaginismus. The study included 32 male partners of vaginismic patients, who presented at a psychiatry department. Subjects were evaluated by a semi-structured questionnaire. The questionnaire was developed by researchers for assessing sexually dysfunctional patients and included detailed questions with regard to socio-demographic variables, general medical and sexual history. All participants also received the Golombok Rust Inventory of Sexual Satisfaction (GRISS). According to DSM-IV-TR criteria, 65.6% of the investigated males were diagnosed with one or more sexual dysfunctions. The most common problem was premature ejaculation (50%) and the second one was erectile dysfunction (28%). The transformed GRISS subscale scores provided similar data. It is concluded that the assessment of sexual functions of males who have vaginismic partners should be an integral part of the management procedure of vaginismus for optimal outcome.

  1. 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 1000μgmL(-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 500μgmL(-1) compared with CTRL-500μgmL(-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.

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

    PubMed

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

    2013-03-07

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

  3. Sexual cannibalism increases male material investment in offspring: quantifying terminal reproductive effort in a praying mantis.

    PubMed

    Brown, William D; Barry, Katherine L

    2016-06-29

    Models of the evolution of sexual cannibalism argue that males may offset the cost of cannibalism if components of the male body are directly allocated to the eggs that they fertilize. We tested this idea in the praying mantid Tenodera sinensis Males and females were fed differently radiolabelled crickets and allowed to mate. Half of the pairs progressed to sexual cannibalism and we prevented cannibalism in the other half. We assess the relative allocation of both male-derived somatic materials and ejaculate materials into the eggs and soma of the female. Our results show that male somatic investment contributes to production of offspring. The eggs and reproductive tissues of cannibalistic females contained significantly more male-derived amino acids than those of non-cannibalistic females, and there was an increase in the number of eggs produced subsequent to sexual cannibalism. Sexual cannibalism thus increases male material investment in offspring. We also show that males provide substantial investment via the ejaculate, with males passing about 25% of their radiolabelled amino acids to females via the ejaculate even in the absence of cannibalism.

  4. Emotional concerns and treatment of male partners of female sexual abuse survivors.

    PubMed

    Chauncey, S

    1994-11-01

    Many men are discovering that they are involved with women who were sexually abused as children. However, male partners of female sexual abuse survivors have thus far received little attention in the literature. As these men increasingly seek treatment with concerns of their own, social workers must become familiar with their emotional experiences and treatment needs. This article outlines the major concerns expressed by 20 male partners of sexual abuse survivors. These concerns included conflicts about expressing needs, frustration with various aspects of their relationships, guilt and shame at having feelings, questions about how to deal with relatives, and sexual issues. The author recommends a treatment approach that combines attention to both the individual's and the couple's concerns and uses insight and the safety of the therapeutic relationship to promote growth. The importance of further outreach to partners of women who were sexually abused as children and the need for increased attention to other partner populations are highlighted.

  5. Postpartum Sterilization

    MedlinePlus

    f AQ FREQUENTLY ASKED QUESTIONS FAQ052 CONTRACEPTION Postpartum Sterilization • What is sterilization? • What is postpartum sterilization? • How is postpartum sterilization performed? • What kind of anesthesia is used for postpartum sterilization? • How ...

  6. Sexual selection by cryptic female choice on male seminal products - a new bridge between sexual selection and reproductive physiology.

    PubMed

    Eberhard, W G; Cordero, C

    1995-12-01

    Selection clearly focuses on differences in reproduction, but studies of reproductive physiology generally have been carried out in a near vacuum of modern evolutionary theory. This lack of contact between the two fields may be about to change. New ideas indicate that sexual selection by cryptic female choice has affected the evolution of products in male semen that influence female reproductive behavior and physiology.

  7. Men's constructions of masculinity and male sexuality through talk of buying sex.

    PubMed

    Huysamen, Monique; Boonzaier, Floretta

    2015-01-01

    Commercial sex is an everyday occurrence across a range of contexts in South Africa. In this paper we turn our attention to the often-marginalised role of the buyers of sex by drawing on narrative interviews with male clients of female sex workers recruited through online advertisements in order to explore the ways in which heterosexual men construct, negotiate and perform their masculinity and sexuality through talking about their experiences of paying for sex. We highlight parallels between men's narratives of paying for sex and dominant discourses of gender and heterosexuality. We show how men draw on heteronormative sexual scripts in constructing and making sense of paid sexual encounters and how men are simultaneously able to construct and enact a particular idealised version of masculinity and male sexuality through their talk on paying for sex. Finally, we discuss how online resources could be used more extensively in future research with the male clients of sex workers.

  8. Influences of dopamine and glutamate in the medial preoptic area on male sexual behavior.

    PubMed

    Will, Ryan G; Hull, Elaine M; Dominguez, Juan M

    2014-06-01

    Several brain nuclei interact to orchestrate the appetitive and consummatory aspects of male sexual behavior. Of these structures, the medial preoptic area (mPOA) of the hypothalamus is of particular interest, as it receives input from all sensory modalities, and damage to this region disrupts copulation in a wide variety of taxa. Furthermore, the mPOA is both responsive to gonadal hormones and involved in endocrine regulation. Neurochemical studies have demonstrated that both dopamine and glutamate levels rise in the mPOA in response to sexual activity, while antagonism of these neurotransmitters impairs male sexual response. Here we review how dopamine and glutamate act in the mPOA to modulate male sexual behavior.

  9. Chronic social stress in puberty alters appetitive male sexual behavior and neural metabolic activity.

    PubMed

    Bastida, Christel C; Puga, Frank; Gonzalez-Lima, Francisco; Jennings, Kimberly J; Wommack, Joel C; Delville, Yvon

    2014-07-01

    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 were altered by social subjugation.

  10. "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.

  11. Sexual Risk Behavior among Male and Female Truant Youths: Exploratory, Multi-Group Latent Class Analysis

    PubMed Central

    Dembo, Richard; Wareham, Jennifer; Krupa, Julie; Winters, Ken C.

    2015-01-01

    Little is known of sexual risk behaviors among truant youths across gender. This study utilized latent class analysis to examined heterogeneity of sexual risk behaviors across gender among a sample of 300 truant adolescents. Results revealed two latent subgroups within gender: low vs. high sexual risk behaviors. There were gender differences in baseline covariates of sexual risk behaviors, with male truants in higher risk group experiencing ADHD (attention deficit hyperactivity disorder) problems, and female truants in higher risk group experienced marijuana use and depression symptoms. African-American race was a significant covariate for high sexual risk behaviors for both genders. Service and practice implications of sexual risk issues of truant youth are discussed. PMID:27066517

  12. Critical Influences on Sexual Minority College Males' Meaning-Making of Their Multiple Identities

    ERIC Educational Resources Information Center

    Tillapaugh, Daniel

    2015-01-01

    This grounded theory study explored the critical influences on college sexual minority males' meaning-making of their multiple identities. Twenty-six cisgender males attending colleges and universities within the United States and Canada were interviewed and provided journal responses to specific prompts. Four themes emerged, including:…

  13. The Sexually Abused Child: A Comparison of Male and Female Victims.

    ERIC Educational Resources Information Center

    Pierce, Robert; Pierce, Lois Hauck

    1985-01-01

    Twenty-five substantiated cases of sexual abuse involving male children were compared with 180 substantiated cases involving female children. Significant differences between female and male victims were observed in family composition, perpetrator of the abuse, variables contributing to continuation of the abusive situation, and type of services…

  14. A sexual conflict in collared flycatchers, Ficedula albicollis: early male moult reduces female fitness

    PubMed Central

    Hemborg, C.; Meril, J.

    1998-01-01

    A sexual conflict over levels of parental care occurs in most animals with biparental care, and studies of sexual differences in levels of parental care have usually focused on its intra-annual fitness consequences. We investigated inter-annual fitness consequences of a sexual difference in timing of feather replacement (moult) in collared flycatchers (Ficedula albicollis). In this study, males overlapped reproduction and moult more often than females, they also initiated their moult at an earlier stage of breeding than females. Females mated to males with a moult-breeding overlap had significantly lowered survival chances than females mated with males initiating moult after breeding. Furthermore, females mated with moulting males risked a lowered future fecundity in terms of a delayed start to breeding in the following season. However, early moulting males achieved a similar reproductive success as males initiating moult after breeding. Likewise, male survival probability to the following breeding season did not differ between early and late moulting individuals, nor was there any evidence that males gained or lost in future mating advantages by moulting early. These results show not only that a sexual conflict over timing of moult may operate, but also that it can impose severe fitness consequences, in terms of reduced future fecundity and survival probability, upon the 'losing' sex.

  15. 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…

  16. Intrapersonal and Familial Effects of Child Sexual Abuse on Female Partners of Male Survivors

    ERIC Educational Resources Information Center

    Jacob, Christine M. Anderson; Veach, Patricia McCarthy

    2005-01-01

    Intrapersonal and familial effects of childhood sexual abuse (CSA) were investigated by interviewing 10 female partners of male survivors. Consensual qualitative research analysis (C. Hill, B. Thompson, & E. Nutt Williams, 1997) yielded 13 domains describing male partner, female partner, couple, and family functioning. Findings concerning…

  17. Male Readership Differences in Liquor Magazine Ads Employing Nonsensical and Sexual Humor.

    ERIC Educational Resources Information Center

    Reid, Leonard N.; And Others

    A study examined the attention getting value of nonsensical and sexual humor used in liquor advertisements to determine if one was more effective than the other in attracting male magazine readers. Thirty-two Starch-scored liquor ads taken from 1976 and 1977 issues of "Time,""Newsweek," and "Sports Illustrated" were analyzed by three male readers.…

  18. Influential Factors on Adolescent Males' Non-Relational Sexual Attitudes and Behavior

    ERIC Educational Resources Information Center

    Drew, Cathy L.

    2013-01-01

    Adolescent males are influenced by various social and cultural factors. This qualitative study sought to further understanding about adolescent males' thoughts and behaviors regarding sexual decision-making. Specific exploration encompassed the influences of the identified factors of parents, peers, media, first romantic relationship breakups, and…

  19. Evolution of male and female genitalia following release from sexual selection.

    PubMed

    Cayetano, Luis; Maklakov, Alexei A; Brooks, Robert C; Bonduriansky, Russell

    2011-08-01

    Despite the key functions of the genitalia in sexual interactions and fertilization, the role of sexual selection and conflict in shaping genital traits remains poorly understood. Seed beetle (Callosobruchus maculatus) males possess spines on the intromittent organ, and females possess a thickened reproductive tract wall that also bears spines. We investigated the role of sexual selection and conflict by imposing monogamous mating on eight replicate populations of this naturally polygamous insect, while maintaining eight other populations under polygamy. To establish whether responses to mating system manipulation were robust to ecological context, we simultaneously manipulated life-history selection (early/late reproduction). Over 18-21 generations, male genital spines evolved relatively reduced length in large males (i.e., shallower static allometry) in monogamous populations. Two nonintromittent male genital appendages also evolved in response to the interaction of mating system and ecology. In contrast, no detectable evolution occurred in female genitalia, consistent with the expectation of a delayed response in defensive traits. Our results support a sexually antagonistic role for the male genital spines, and demonstrate the evolution of static allometry in response to variation in sexual selection opportunity. We argue that further advances in the study of genital coevolution will require a much more detailed understanding of the functions of male and female genital traits.

  20. Exploiting a moment of weakness: male spiders escape sexual cannibalism by copulating with moulting females.

    PubMed

    Uhl, Gabriele; Zimmer, Stefanie M; Renner, Dirk; Schneider, Jutta M

    2015-11-26

    Sexual cannibalism is a particularly extreme example of conflict between the sexes, depriving the male of future reproduction. Theory predicts that sexual conflict should induce counter-adaptations in the victim. Observations of male spiders mating with moulting and hence largely immobile females suggest that this behaviour functions to circumvent female control and cannibalism. However, we lack quantitative estimates of natural frequencies and fitness consequences of these unconventional matings. To understand the importance of mating while moulting in cannibalistic mating systems, we combined mating experiments and paternity assessment in the laboratory with extensive field observations using the sexually cannibalistic orb-web spider Argiope bruennichi. Copulations with moulting females resulted in 97% male survival compared with only 20% in conventional matings. Mating while moulting provided similar paternity benefits compared with conventional matings. Our findings support the hypothesis that mating with moulting females evolved under sexual conflict and safely evades sexual cannibalism. Despite male benefits, natural frequencies were estimated around 44% and directly predicted by a male guarding a subadult female. Since only adult females signal their presence, the difficulty for males to locate subadult females might limit further spreading of mating with moulting females.

  1. Prevention of cadmium-induced sterility by zinc in the male rat.

    PubMed

    Saksena, S; White, M J; Mertzlufft, J; Lau, I

    1983-05-01

    The potential of zinc (Zn) to antagonize the adverse effects of cadmium (Cd) on the male reproductive processes was studied. A significant reduction in the weights of the testis and epididymis, the testicular sperm population and oligospermia to azoospermia in the epididymis was recorded in rats treated once s.c. with 2 mg/kg Cd and sacrificed 20 days later. This was accompanied by a significantly reduced serum T and a loss of fertility. Administration of a single s.c. injection of Zn (80 mg/kg) did not alter significantly any of the reproductive parameters studied. On the other hand, Zn given 1/2 to 2 h after Cd resulted in partial recovery. Organ weights and sperm population in these groups were maintained and the fertility rate was 67% and 50% at 5 and 20 days as compared to 67% and 0% at corresponding period in Cd-exposed males. The protective effect diminished when Zn was given more than 2 h after Cd exposure. The most effective regimen of Zn therapy was an administration of a total dose of 80 mg/kg Zn given in 3 injections (15 mg/kg before, 50 mg/kg at the time and 15 mg/kg 2 h after Cd). The results provide evidence that Zn, if given before or within 2 h of Cd exposure, is capable of at least partially reversing its deleterious effects on spermatogenesis, steroidogenesis and fertility of the male rat.

  2. Regulation of cell divisions and differentiation by MALE STERILITY32 is required for anther development in maize.

    PubMed

    Moon, Jihyun; Skibbe, David; Timofejeva, Ljudmilla; Wang, Chung-Ju Rachel; Kelliher, Timothy; Kremling, Karl; Walbot, Virginia; Cande, William Zacheus

    2013-11-01

    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.

  3. Evasion of predators contributes to the maintenance of male eyes in sexually dimorphic Euphilomedes ostracods (Crustacea).

    PubMed

    Speiser, Daniel I; Lampe, Rebecca I; Lovdahl, Valerie R; Carrillo-Zazueta, Brenna; Rivera, Ajna S; Oakley, Todd H

    2013-07-01

    Sexual dimorphisms have long drawn the attention of evolutionary biologists. However, we still have much to learn about the evolutionary, genetic, and developmental drivers of sexual dimorphisms. Here, we introduce ostracods of the genus Euphilomedes (Myodocopida, Ostracoda, and Crustacea) as a promising new system in which to investigate why and how sexual dimorphisms evolve. First, we ask whether male-skewed selective pressure from pelagic predators may help explain a dramatic sexual dimorphism in which male Euphilomedes have compound eyes, but females do not. Manipulative experiments demonstrate that blindfolding reduces the survival rate of male Euphilomedes when they are exposed to predatory fish. Blindfolding of the female rudimentary eyes (rudiments) does not, however, similarly influence the survival rate of brooding females. Further, numerical estimates of sighting distances, based on reasonable extrapolations from Euphilomedes's eye morphology, suggest that the eyes of male Euphilomedes are useful for detecting objects roughly the size of certain pelagic predators, but not conspecifics. We conclude that eyes do not mediate direct interactions between male and female Euphilomedes, but that differences in predation pressure-perhaps associated with different reproductive behaviors-contribute to maintaining the sexually dimorphic eyes of these ostracods. Second, through transcriptome sequencing, we examined potential gene regulatory networks that could underlie sexual dimorphism in Euphilomedes' eyes. From the transcriptome of juvenile male Euphilomedes' eyes, we identified phototransduction genes and components of eye-related developmental networks that are well characterized in Drosophila and other species. The presence of suites of eye regulatory genes in our Euphilomedes juvenile male transcriptome will allow us, in future studies, to test how ostracods regulate the development of their sexually dimorphic eyes.

  4. Male-sterile and cleistogamous phenotypes in tall fescue induced by chimeric repressors of SUPERWOMAN1 and OsMADS58.

    PubMed

    Sato, Hiroko; Yoshida, Kouki; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Takamizo, Tadashi

    2012-02-01

    Since tall fescue (Festuca arundinacea Schreb.) is an anemophilous (wind-pollinated) grass species, male sterility is strongly desired for transgenic tall fescue to prevent pollen dispersal. To create male-sterile tall fescue, we applied Chimeric REpressor gene-Silencing Technology (CRES-T) based on rice APETALA3 (AP3) and AGAMOUS (AG) orthologues that specify the formation of stamens. We fused the coding regions of rice AP3 orthologue SUPERWOMAN1 (SPW1), and rice AG orthologues, Os12g0207000, Os01g0886200 and OsMADS58, respectively with the artificial sequence encoding the modified EAR-like motif repression domain (SRDX). We first introduced Os12g0207000SRDX, Os01g0886200SRDX and OsMADS58SRDX into rice for evaluation of their abilities to induce male sterility. The transgenic rice expressing OsMADS58SRDX had reiterated formation of lodicule-like organs instead of stamens and carpel, a typical phenotype of ag mutant. Thus, we found that OsMADS58SRDX was most suitable for our purpose. Next, we introduced SPW1SRDX and OsMADS58SRDX into tall fescue. Although the transgenic tall fescue did not have the stamen alterations seen in SPW1SRDX and OsMADS58SRDX rice, they either produced no pollen or produced immature pollen; thus, the anthers were not dehiscent and the plants were male-sterile. In addition to the male sterility, SPW1SRDX tall fescue showed a cleistogamous (closed) phenotype in which anthers were not observed outside the glumes, with thin, abnormally elongated lodicules. Some lines of OsMADS58SRDX tall fescue showed a cleistogamous phenotype in which the lodicules were homeotically transformed into lemma-like organs. In both cases, cleistogamous phenotype was associated with morphological changes to the lodicules. We also obtained a mild phenotype of OsMADS58SRDX tall fescue, which exhibited only the male sterility. In this study, we produced novel male-sterile phenotypes using chimeric repressors and thus suggest CRES-T as a tool for transgenic improvement

  5. Transcriptome sequencing and de novo analysis of cytoplasmic male sterility and maintenance in JA-CMS cotton.

    PubMed

    Yang, Peng; Han, Jinfeng; Huang, Jinling

    2014-01-01

    Cytoplasmic male sterility (CMS) is the failure to produce functional pollen, which is inherited maternally. And it is known that anther development is modulated through complicated interactions between nuclear and mitochondrial genes in sporophytic and gametophytic tissues. However, an unbiased transcriptome sequencing analysis of CMS in cotton is currently lacking in the literature. This study compared differentially expressed (DE) genes of floral buds at the sporogenous cells stage (SS) and microsporocyte stage (MS) (the two most important stages for pollen abortion in JA-CMS) between JA-CMS and its fertile maintainer line JB cotton plants, using the Illumina HiSeq 2000 sequencing platform. A total of 709 (1.8%) DE genes including 293 up-regulated and 416 down-regulated genes were identified in JA-CMS line comparing with its maintainer line at the SS stage, and 644 (1.6%) DE genes with 263 up-regulated and 381 down-regulated genes were detected at the MS stage. By comparing the two stages in the same material, there were 8 up-regulated and 9 down-regulated DE genes in JA-CMS line and 29 up-regulated and 9 down-regulated DE genes in JB maintainer line at the MS stage. Quantitative RT-PCR was used to validate 7 randomly selected DE genes. Bioinformatics analysis revealed that genes involved in reduction-oxidation reactions and alpha-linolenic acid metabolism were down-regulated, while genes pertaining to photosynthesis and flavonoid biosynthesis were up-regulated in JA-CMS floral buds compared with their JB counterparts at the SS and/or MS stages. All these four biological processes play important roles in reactive oxygen species (ROS) homeostasis, which may be an important factor contributing to the sterile trait of JA-CMS. Further experiments are warranted to elucidate molecular mechanisms of these genes that lead to CMS.

  6. Sexual size dimorphism, canine dimorphism, and male-male competition in primates: where do humans fit in?

    PubMed

    Plavcan, J Michael

    2012-03-01

    Sexual size dimorphism is generally associated with sexual selection via agonistic male competition in nonhuman primates. These primate models play an important role in understanding the origins and evolution of human behavior. Human size dimorphism is often hypothesized to be associated with high rates of male violence and polygyny. This raises the question of whether human dimorphism and patterns of male violence are inherited from a common ancestor with chimpanzees or are uniquely derived. Here I review patterns of, and causal models for, dimorphism in humans and other primates. While dimorphism in primates is associated with agonistic male mate competition, a variety of factors can affect male and female size, and thereby dimorphism. The causes of human sexual size dimorphism are uncertain, and could involve several non-mutually-exclusive mechanisms, such as mate competition, resource competition, intergroup violence, and female choice. A phylogenetic reconstruction of the evolution of dimorphism, including fossil hominins, indicates that the modern human condition is derived. This suggests that at least some behavioral similarities with Pan associated with dimorphism may have arisen independently, and not directly from a common ancestor.

  7. Avoidant and compulsive sexual behaviors in male and female survivors of childhood sexual abuse.

    PubMed

    Vaillancourt-Morel, Marie-Pier; Godbout, Natacha; Labadie, Chloé; Runtz, Marsha; Lussier, Yvan; Sabourin, Stéphane

    2015-02-01

    The main objectives of this study were to test a theory-based mediation model in which the relation between childhood sexual abuse (CSA) and dyadic adjustment is mediated through adult sexual avoidance and sexual compulsivity and to examine the gender-invariance of this model. A sample of 686 adults currently involved in a close relationship completed online self-report computerized questionnaires. Prevalence of CSA was 20% in women and 19% in men. In line with our hypotheses, path analyses and structural equation analyses showed that, for both women and men, CSA was associated with more sexual avoidance and sexual compulsivity, which, in turn, predicted lower couple adjustment. Overall, these findings suggest that both avoidant and compulsive sexuality are relevant intervention targets with couples in which one or both partners are CSA survivors.

  8. Masturbation and its relationship to sexual activities of young males in Korean military service.

    PubMed

    Choi, Y J; Lee, W H; Rha, K H; Xin, Z C; Choi, Y D; Choi, H K

    2000-04-01

    This study examined the masturbatory experiences and other sexual activities of young Korean males in military service. The actual status of masturbation and its relationship to sexual activity questionnaire. A total of 1,212 young males among military personnel in Korea were interviewed with sexuality questionnaires on masturbation, sexual intercourse and personal characteristics. We divided these subjects into four groups according to the age of initiation of masturbation and analyzed the relationship between masturbation and other sexual activities. The mean age of subjects was 22.03 +/- 1.22 (19-27) years. The percentage of men who reported ever having masturbated was 98.1% (1189/1212) and the average age of initiation of masturbation was 14.26 +/- 1.66 years. So we divided 1,212 males into four groups on the basis of the average age below and above one standard deviation. Overall, 67.7% (821/1212) had experienced sexual intercourse, and significantly, the earlier the initiation age of masturbation, the higher the coitus rate in each group (p < 0.05). About 21.5% of the men who were not virgins had experienced their first sexual intercourse with prostitutes. The mean age of first coitus, the incidence of sexually transmitted disease (STD) and the frequency of masturbation were closely linked to the initiation age of masturbation, respectively (p < 0.05). A masturbatory guilt feeling was seen in about 10.9% (132/1212) and there was no significant difference according to the types of religious worship (p = 0.227). On the basis of this study, sexual activities generally increased accordingly as the beginning of masturbation was earlier. Coital incidence in this study was 67.7% for young males in Korean military service, and 21.5% of them had their first sexual intercourse with prostitutes. Prostitution still plays an important role in the sexual lives of males in Korea. The incidence of STD was over 10% and homosexual manifestation was seen in 1.07% of subjects

  9. Genetic differences among populations in sexual dimorphism: evidence for selection on males in a dioecious plant

    PubMed Central

    YU, Q.; ELLEN, E. D.; WADE, M. J.; DELPH, L. F.

    2011-01-01

    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 (QST) to that of neutral genetic markers (FST) 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 QST/FST 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

  10. 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.

  11. Differences in legal outcomes for male and female children who have been sexually abused.

    PubMed

    Edelson, Meredyth Goldberg; Joa, Debbie

    2010-12-01

    The goal of the present study was to determine whether or not there were sex differences in legal outcomes for children who were sexually abused. Using the methodology of Joa and Edelson (2004), the results indicated that males who were sexually abused had poorer legal outcomes than females. Specifically, it was found that cases involving male victims were less likely to be filed with the District Attorney (DA) than cases involving female victims and had fewer criminal counts charged. For those children seen at a Child Abuse Assessment Center, cases involving female victims were significantly more likely to be filed by the DA's office than were cases involving male victims. Finally, there were differences in whether guilty defendants pled guilty or were found guilty at trial depending on whether the defendant sexually abused a male or female. The implications of the findings are discussed.

  12. Pornography and the Male Sexual Script: An Analysis of Consumption and Sexual Relations.

    PubMed

    Sun, Chyng; Bridges, Ana; Johnson, Jennifer A; Ezzell, Matthew B

    2016-05-01

    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.

  13. Do Males Form Social Associations Based on Sexual Attractiveness in a Fission-Fusion Fish Society?

    PubMed Central

    Auge, Anne-Christine; Auld, Heather L.; Sherratt, Thomas N.; Godin, Jean-Guy J.

    2016-01-01

    Recent theory predicts that males should choose social environments that maximize their relative attractiveness to females by preferentially associating with less attractive rivals, so as to enhance their mating success. Using the Trinidadian guppy (Poecilia reticulata), a highly social species, we tested for non-random social associations among males in mixed-sex groups based on two phenotypic traits (body length and coloration) that predict relative sexual attractiveness to females and sexual (sperm) competitiveness. Based on a well-replicated laboratory dichotomous-choice test of social group preference, we could not reject the null hypothesis that focal males chose randomly between a mixed-sex group that comprised a female and a rival male that was less sexually attractive than themselves and another mixed-sex group containing a sexually more attractive male. The same conclusion was reached when females were absent from the two groups. As might be expected from these laboratory findings, free-ranging males in the field were not assorted by either body length or colour in mixed-sex shoals. The apparent lack of an evolved and expressed preference in wild male guppies from our study population to form social associations with other males based on their relative sexual attractiveness and competitiveness might be due to the fission-fusion dynamics of guppy shoals in nature. Such social dynamics likely places constraints on the formation of stable phenotype-based social associations among males. This possibility is supported by a simulation model which assumes group departure rules based on relative body size and coloration in males. PMID:26986565

  14. Sexual Concerns of Male Spouses of Female Alzheimer's Disease Patients.

    ERIC Educational Resources Information Center

    Litz, Brett T.; And Others

    1990-01-01

    Presents case study which highlights attendant cognitive changes that occur in Alzheimer's patient, presenting caregiver with challenges to couple's sexual functioning. Describes man who reported erectile dysfunction directly stemming from stressful changes that had occurred in his relationship to his wife who had Alzheimer's disease. General…

  15. Female and Male Undergraduates' Attributions for Sexual Offending against Children.

    ERIC Educational Resources Information Center

    Beling, Joel; Hudson, Stephen M.; Ward, Tony

    2001-01-01

    Examines gender differences in undergraduates' attributions for child sex offending. Results showed that undergraduates' reasons for child sexual abuse strongly parallel contemporary scientific theories of abuse, and that there were significant gender differences in the frequency with which participants cited various types of reasons given for…

  16. 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…

  17. 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

  18. 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 (β =.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 (β=.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

  19. Concurrent natural and sexual selection in wild male sockeye salmon, Oncorhynchus nerka.

    PubMed

    Hamon, Troy R; Foote, Chris J

    2005-05-01

    Concurrent natural and sexual selection have been inferred from laboratory and comparative studies in a number of taxa, but are rarely measured in natural populations. Because the interaction of these two general categories of selection may be complex when they occur simultaneously, empirical evidence from natural populations would help us to understand this interaction and probably give us greater insight into each separate episode as well. In male sockeye salmon, sexual selection for larger body size has been indicated in both deep and shallow water habitats. However, in shallow habitats male sockeye are generally smaller and less deep-bodied than in deep habitats, a difference that has been ascribed to natural selection. We measured concurrent natural and sexual selection in two years on breeding male sockeye salmon with respect to body size, body shape, and time of arrival to the breeding grounds. Natural selection was variable in effect and sexual selection was variable in intensity in these two years. The patterns of selection also appear to be interdependent; areas where predation on spawning adults is not intense have yielded different patterns of sexual selection than those measured here. It appears that some of the body shape differences in sockeye salmon associated with different spawning habitats, which were previously attributed to selective mortality, may be a result of different patterns of sexual selection in the different habitats. Total selection resulting from the combination of both natural and sexual selection was less intense than either natural or sexual selection in most cases. Measurement of concurrent selection episodes in nature may help us to understand whether the pattern of differential sexual selection is common, and whether observed patterns of habitat-related differentiation may be due to differences in sexual selection.

  20. Effects of chronically elevated intake of sweet solutions on sexual behavior of male rats.

    PubMed

    Lieblich, I; Shaviv, P; Cohen, E

    1985-09-01

    Three experiments were conducted on the sexual behavior of gonadally intact and castrated male Sabra rats. Half of the animals drank water during the course of the experiment and half were offered sweet solutions, the assumption being that sweet gustatory stimulation elevates the level of central endogenous opioid peptides in rats. The effects on sexual behavior of the following drugs were explored: the opiate receptor blocker naloxone (5 mg/kg, sc), the serotonin precursor 5-hydroxytryptophan (5-HTP) (20 mg/kg, sc), the serotonin antagonist methysergide (1 mg/kg, sc), and naloxone in combination with methysergide. Naloxone, whether administered alone or in combination with methysergide, impaired sexual performance in castrated male rats, and in gonadally intact rats maintained on sweet solutions. Methysergide elevated sexual behavior in all groups, whereas 5-HTP tended to suppress such behavior. The results support the hypothesis that endogenous opiates play a role in the expression of male sexual behavior in rats. While subtle in intact animals this role may become crucial following the disruption of sex hormone supply. Serotonergic influence on male sexual behavior is inhibitory.

  1. The role of adrenoceptors in the central nervous system in male and female rat sexual behavior.

    PubMed

    Snoeren, Eelke M S

    2015-04-15

    Three different phases can be distinguished in rats' sexual cycle, the introductory (precopulatory), the copulatory and the executive (ejaculatory) phases. In this review, a new analysis of existing pharmacological data is made, both in male and female rats, in which the different aspects of sexual behavior are taken into account. An effort is made to distinguish pharmacological effects on sexual behavior from a possible physiological role of noradrenaline. In addition, new data on the role of α2-adrenoceptors on female sexual behavior is presented. The new analysis suggests that noradrenaline has a stimulatory role on the executive phase of male sexual behavior, while the introductory and copulatory phases remain unaffected. Adrenoceptors play a role in the regulation of sexual behavior in the medial preoptic area and the lateral septum. In female rats, noradrenaline also does not play a vital role in the introductory phase. Only the lordosis behavior of the copulatory phase is sometimes affected by adrenergic agents, but only under a certain hormonal condition. The medial preoptic area, the ventromedial nucleus, the arcuate ventromedial nucleus and median eminence are involved in the regulation of female sexual behavior. The new data suggest that α2-adrenoceptors play no major role on any indices of female sexual behavior.

  2. [Gender and sexuality: fragments of male identity in the Aids era

    PubMed

    Mota

    1998-04-30

    This paper focuses on specific aspects of male sexuality and how this sexual identity is built in the Aids era, based on conversations with low-income youth, ages 14-21 years, living in Greater Metropolitan Rio de Janeiro. We examine how Aids is perceived and investigate sexuality in this epidemic context. The goal is to provide concrete data to support a prevention campaign and contribute to preventive policies in Brazilian society. The proposal is based on the sexual identity of this gender/age group, comparing their reports on sexual practice. We used a partially open-ended interview protocol. We focus on the way young males choose their sexual identity under the premise that this is how men can become the channel for Aids transmission. Our research was thus based on gender and sexual identity as categories. Our results indicate that for a young man, 'being a man' means having an active sexual life, thus creating a stereotype placing them at risk for HIV transmission.

  3. 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.

  4. Effect of different types of textiles on male sexual activity.

    PubMed

    Shafik, A

    1996-01-01

    The effect of different types of textile underpants on sexual activity was studied in 50 men. All the subjects were potent and sexually active. They were divided into 5 equal groups: 4 test and 1 control. Each of the 4 test groups were dressed in one type of textile underpants made of either 100% polyester, 50/50% polyester/cotton mix, 100% cotton, or 100% wool. Sexual behavior was assessed before and after 6 and 12 months of wearing the pants, and 6 months after their removal. Behavioral response was rated as potent if the subject's penis became erect, entered the vagina, and ejaculated. The rate of potent intromission (I) to mounts (M) (I/M ratio) was determined. The electrostatic potentials (EP) generated on the penis and scrotum were measured by an electrostatic kilovoltmeter. The I/M ratio at 6 and 12 months of wearing the polyester and polyester/cotton mix pants was significantly reduced compared to the pretest levels and the controls (p < .001). The reduction was more manifest in the pure polyester than in the polyester/cotton mix group, and at the 12-month than at the 6-month examination. The I/M ratio of the cotton and wool groups showed insignificant changes during the study period. Six months after removal of the underpants, the I/M ratio had returned to the pretest levels in the two groups that had worn polyester-containing pants. The polyester-containing pants generated EP, which may induce electrostatic fields in the intrapenile structures and could explain the diminished sexual activity. The cotton and wool textiles did not generate EP. Thus, polyester underpants could have an injurious effect on human sexual activity.

  5. 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.

  6. Sexual Dysfunction in Male Subjects Receiving Trifluoperazine, Risperidone, or Olanzapine: Rates Vary With Assessment Questionnaire

    PubMed Central

    Nebhinani, Naresh; Avasthi, Ajit

    2012-01-01

    Objective: To assess the rate and typology of sexual dysfunction in male subjects receiving trifluoperazine, risperidone, or olanzapine using the Arizona Sexual Experience Scale (ASEX), the Psychotropic Related Sexual Dysfunction Questionnaire (PRSexDQ), and the sexual function section of the modified Udvalg for Kliniske Undersøgelser Side Effect Rating Scale (UKU). Method: The sample included 100 men with psychotic disorders (F2 category of the ICD-10) and receiving trifluoperazine (n = 20), risperidone (n = 30), or olanzapine (n = 50) for at least 3 months’ duration. Subjects with a history of sexual dysfunction prior to antipsychotic intake or chronic medical illness were excluded. A cross-sectional design was employed, and data were collected over a 1½-year period from March 2009 to August 2010. Results: The rate of sexual dysfunction varied from scale to scale among the 100 subjects. The rate of sexual dysfunction was 25% on the ASEX, 37% on the PRSexDQ, and 40% on the UKU. Sexual dysfunction in the trifluoperazine, risperidone, and olanzapine groups was 20%, 43%, and 16%, respectively, on the ASEX; 35%, 50%, and 30%, respectively, on the PRSexDQ; and 40%, 50%, and 34%, respectively, on the UKU. The most common sexual dysfunction as assessed on all scales was decreased libido, except for the risperidone group on the ASEX. Conclusions: Sexual dysfunction is quite prevalent in subjects receiving antipsychotic medications. In our study, rate of sexual dysfunction was highest for risperidone, followed by trifluoperazine and olanzapine. However, the rate of sexual dysfunction varied from scale to scale. Hence, there is a need for a comprehensive instrument to assess sexual dysfunction in patients receiving antipsychotics. PMID:22943029

  7. Acquired resistance affects male sexual display and female choice in guppies

    PubMed Central

    pez, S. L

    1998-01-01

    Is resistance to parasites related to the expression of male secondary sex characters? Handicap models predict a positive relationship, proposing that males displaying extravagant sex characters may be honestly signalling their resistance to females. However, no current evidence addresses whether individual changes in immunity (acquired resistance) are reflected in sexual traits. In this experiment I use guppies to compare male orange colour, sigmoid display and female preferences for individual males, before and after a primary challenge infection of males. Challenge infections were terminated chemically and fish were given ten days' recovery time before proceeding with the second measurements. The degree of acquired resistance was quantified a posteriori, by exposing males to a secondary infection. Sigmoid display rates and female preference for males differed for males of different resistance groups after challenge infection only. This difference was due to resistant males displaying more than non-resistant ones. No differences were detected in male orange colour, but this may be because colour needs a longer time than ten days to be recovered and adjusted. The results show that the level of acquired resistance affects sexual display and attractiveness in guppies. They suggest that once an effective immunity is built up by a male, he can afford to incur higher costs for sexual characteristics, whereas a male that lacks the ability to build up effective resistance cannot. These costs probably consist of higher energy expenditure and/or higher circulating levels of testosterone, which may be needed to increase display. Priming and effective establishment of an individual's resistance to parasitic infection could eventually result in a higher availability of resources for sexual functions.

  8. Strong sexual selection in males against a mutation load that reduces offspring production in seed beetles.

    PubMed

    Grieshop, K; Stångberg, J; Martinossi-Allibert, I; Arnqvist, G; Berger, D

    2016-06-01

    Theory predicts that sexual reproduction can increase population viability relative to asexual reproduction by allowing sexual selection in males to remove deleterious mutations from the population without large demographic costs. This requires that selection acts more strongly in males than females and that mutations affecting male reproductive success have pleiotropic effects on population productivity, but empirical support for these assumptions is mixed. We used the seed beetle Callosobruchus maculatus to implement a three-generation breeding design where we induced mutations via ionizing radiation (IR) in the F0 generation and measured mutational effects (relative to nonirradiated controls) on an estimate of population productivity in the F1 and effects on sex-specific competitive lifetime reproductive success (LRS) in the F2 . Regardless of whether mutations were induced via F0 males or females, they had strong negative effects on male LRS, but a nonsignificant influence on female LRS, suggesting that selection is more efficient in removing deleterious alleles in males. Moreover, mutations had seemingly shared effects on population productivity and competitive LRS in both sexes. Thus, our results lend support to the hypothesis that strong sexual selection on males can act to remove the mutation load on population viability, thereby offering a benefit to sexual reproduction.

  9. Effects of prenatal hydrocortisone acetate exposure on fertility and sexual behavior in male rats.

    PubMed

    Pereira, Oduvaldo C M; Arena, Arielle C; Yasuhara, Fabiana; Kempinas, Wilma G

    2003-08-01

    The aim of the present study was to investigate the effects of hydrocortisone during the prenatal period and its later repercussions on the fertility and sexual behavior of male rats. Pregnant rats were treated (s.c.) with hydrocortisone acetate, at 1.5 mg/day on the 17th, 18th, and 19th days of gestation. Decreased body weight and no alteration in anogenital distance were observed in male offspring. Adulthood, presented reductions of body weight, plasma testosterone levels, and seminal-vesicle wet weight without secretion as well as no alteration in the wet weights of the testes, epididymis, and seminal vesicle with secretion in the treated group. Males exposed to hydrocortisone during the prenatal period were able to mate with normal females, which became pregnant but exhibited an increased number of post-implantation losses. In spite of this, these treated males exhibited decreased male sexual behavior and the appearance of female sexual behavior after these male rats were castrated and pretreated with exogenous estrogen. These results indicate that exposure to hydrocortisone in the later stages of pregnancy may have a long-term effect on the fertility and sexual behavior of male rats, suggesting an incomplete masculinization and defeminization of the central nervous system.

  10. Sexual Behavior in Male Adolescents with Autism and Its Relation to Social-Sexual Skills in the Kingdom of Saudi Arabia

    ERIC Educational Resources Information Center

    Huwaidi, Mohamed A.; Daghustani, Wid H.

    2013-01-01

    The present study aimed to identify common sexual behavior among adolescents with autism, where parents and teachers of sixty-one male adolescents from twelve to twenty-one years of age were recruited from three cities in the Kingdom of Saudi Arabia. They were asked to respond to a sexual behavior questionnaire, and a social-sexual skills…

  11. 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…

  12. The genetic architecture of sexual conflict: male harm and female resistance in Callosobruchus maculatus.

    PubMed

    Gay, L; Brown, E; Tregenza, T; Pincheira-Donoso, D; Eady, P E; Vasudev, R; Hunt, J; Hosken, D J

    2011-02-01

    Males harm females during mating in a range of species. This harm is thought to evolve because it is directly or indirectly beneficial to the male, despite being costly to his mate. The resulting sexually antagonistic selection can cause sexual arms races. For sexually antagonistic co-evolution to occur, there must be genetic variation for traits involved in female harming and susceptibility to harm, but even then intersexual genetic correlations could facilitate or impede sexual co-evolution. Male Callosobruchus maculatus harm their mates during copulation by damaging the female's reproductive tract. However, there have been no investigations of the genetic variation in damage or in female susceptibility to damage, nor has the genetic covariance between these characters been assessed. Here, we use a full-sib/half-sib breeding design to show that male damage is heritable, whereas female susceptibility to damage is much less so. There is also a substantial positive genetic correlation between the two, suggesting that selection favouring damaging males will increase the prevalence of susceptible females. We also provide evidence consistent with intralocus sexual conflict in this species.

  13. Comparative Transcriptome Profile of the Cytoplasmic Male Sterile and Fertile Floral Buds of Radish (Raphanus sativus L.).

    PubMed

    Mei, Shiyong; Liu, Touming; Wang, Zhiwei

    2016-01-06

    Radish cytoplasmic male sterility (CMS) has been widely used for breeding in Raphanus and Brassica genera. However, the detailed regulation network of the male sterility remains to be determined. Our previous work has shown that the abnormalities in a CMS radish appeared shortly after the tetrad stage when microspores were malformed and the tapetal cells grew abnormally large. In this work, histological analysis shows that anthers are at the tetrad stage when the radish buds are about 1.5 mm in length. Furthermore, a high throughput RNA sequencing technology was employed to characterize the transcriptome of radish buds with length about 1.5 mm from two CMS lines possessing the CMS-inducing orf138 gene and corresponding near-isogenic maintainer lines. A total of 67,140 unigenes were functionally annotated. Functional terms for these genes are significantly enriched in 55 Gene Ontology (GO) groups and 323 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The transcriptome detected transcripts for 72 out of a total of 79 protein genes encoded in the chloroplast genome from radish. In contrast, the radish mitochondrial genome contains 34 protein genes, but only 16 protein transcripts were detected from the transcriptome. The transcriptome comparison between CMS and near-isogenic maintainer lines revealed 539 differentially expressed genes (DEGs), indicating that the false positive rate for comparative transcriptome profiling was clearly decreased using two groups of CMS/maintainer lines with different nuclear background. The level of 127 transcripts was increased and 412 transcripts were decreased in the CMS lines. No change in levels of transcripts except CMS-inducing orf138 was identified from the mitochondrial and chloroplast genomes. Some DEGs which would be associated with the CMS, encoding MYB and bHLH transcription factors, pentatricopeptide repeat (PPR) proteins, heat shock transcription factors (HSFs) and heat shock proteins (HSPs), are discussed. The

  14. Heterosexual Men's Anger in Response to Male Homosexuality: Effects of Erotic and Non-Erotic Depictions of Male-Male Intimacy and Sexual Prejudice

    PubMed Central

    Hudepohl, Adam D.; Parrott, Dominic J.; Zeichner, Amos

    2010-01-01

    The present study compared effects of erotic and non-erotic depictions of male-male intimacy on the experience of anger in heterosexual men. Data came from three independent laboratory studies designed to elicit anger in response to erotic or non-erotic depictions of male-male and male-female intimacy. All participants completed a measure of sexual prejudice and anger was assessed before and after viewing the erotic or non-erotic video. Among high-prejudiced men, viewing erotic and non-erotic intimate behavior between two men elicited significant increases in anger relative to viewing comparable behavior between a male-female dyad. In contrast, among low-prejudiced men, viewing erotic, but not non-erotic, intimate behavior between two men elicited significant increases in anger relative to viewing comparable behavior between a male-female dyad. Implications for understanding heterosexual men's anger, and aggression, toward gay men were discussed. PMID:20818528

  15. Genetic dissection of hybrid incompatibilities between Drosophila simulans and D. mauritiana. I. Differential accumulation of hybrid male sterility effects on the X and autosomes.

    PubMed Central

    Tao, Yun; Chen, Sining; Hartl, Daniel L; Laurie, Cathy C

    2003-01-01

    The genetic basis of hybrid incompatibility in crosses between Drosophila mauritiana and D. simulans was investigated to gain insight into the evolutionary mechanisms of speciation. In this study, segments of the D. mauritiana third chromosome were introgressed into a D. simulans genetic background and tested as homozygotes for viability, male fertility, and female fertility. The entire third chromosome was covered with partially overlapping segments. Many segments were male sterile, while none were female sterile or lethal, confirming previous reports of the rapid evolution of hybrid male sterility (HMS). A statistical model was developed to quantify the HMS accumulation. In comparison with previous work on the X chromosome, we estimate that the X has approximately 2.5 times the density of HMS factors as the autosomes. We also estimate that the whole genome contains approximately 15 HMS "equivalents"-i.e., 15 times the minimum number of incompatibility factors necessary to cause complete sterility. Although some caveats for the quantitative estimate of a 2.5-fold density difference are described, this study supports the notion that the X chromosome plays a special role in the evolution of reproductive isolation. Possible mechanisms of a "large X" effect include selective fixation of new mutations that are recessive or partially recessive and the evolution of sex-ratio distortion systems. PMID:12930747

  16. Trajectories of male sexual aggression from adolescence through college: A latent class growth analysis.

    PubMed

    Swartout, Kevin M; Swartout, Ashlyn G; Brennan, Carolyn L; White, Jacquelyn W

    2015-01-01

    Approximately 25% of male college students report engaging in some form of sexual coercion by the end of their fourth year of college. White and Smith (2004) found that negative childhood experiences-childhood sexual abuse, childhood physical abuse, and witnessing domestic violence-predicted sexual aggression perpetrated before college, but not during the subsequent college years, a puzzling finding in view of the reasonably consistent rates of sexual aggression from adolescence to the first 2 years of college. The current study takes a person-centered approach to sexual aggression in an attempt to resolve this discrepancy. We examined the possibility of cohesive subgroups of men in terms of their frequency of sexual aggression across the pre-college and college years. A series of latent class growth models were fit to an existing longitudinal dataset of sexual experiences collected across four time points-pre-college through year 3 of college. A four-trajectory model fit the data well, exhibiting significantly better fit than a three-trajectory model. The four trajectories are interpreted as men who perpetrate sexual aggression at (1) low (71.5% of the sample), (2) moderate (21.2%), (3) decreasing (4.2%), and (4) increasing (3.1%) frequencies across time. Negative childhood experiences predicted membership of the decreasing trajectory, relative to the low trajectory, but did not predict membership of the increasing trajectory, explaining the discrepancy uncovered by White and Smith. Implications for primary prevention of sexual aggression are discussed.

  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. Linkage between sexual orientation and chromosome Xq28 in males but not in females.

    PubMed

    Hu, S; Pattatucci, A M; Patterson, C; Li, L; Fulker, D W; Cherny, S S; Kruglyak, L; Hamer, D H

    1995-11-01

    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 families but not for the lesbian families or for families that failed to meet defined inclusion criteria for the study of sex-linked sexual orientation. Our results corroborate the previously reported linkage between Xq28 and male homosexuality in selected kinships and suggest that this region contains a locus that influences individual variations in sexual orientation in men but not in women.

  19. Sexual Competitiveness of Anastrepha ludens (Diptera: Tephritidae) Males Exposed to Citrus aurantium and Citrus paradisi Essential Oils.

    PubMed

    Morató, Santiago; Shelly, Todd; Rull, Juan; Aluja, Martin

    2015-04-01

    Males of the Mediterranean fruit fly (Ceratitis capitata (Wiedemann)) display increased mating competitiveness following exposure to the odor of certain host and nonhost plants, and this phenomenon has been used in the sterile insect technique to boost the mating success of released, sterile males. Here, we aimed to establish whether males of the Mexican fruit fly (Anastrepha ludens (Loew)) gain a mating advantage when exposed to the aroma of two preferred hosts, grapefruit (Citrus paradisi Macfadyen) and bitter orange (Citrus aurantium L.). Under seminatural conditions, we observed that, in trials using wildish males (from a young laboratory colony started with wild flies) exclusively, exposure to the aroma of bitter orange had no effect on male mating success but exposure to the odor grapefruit oil increased male mating success significantly. In a separate test involving both exposed and nonexposed wildish and mass-reared, sterile males, although wildish males were clearly more competitive than sterile males, exposure to grapefruit oil had no detectable effect on either male type. Exposure to oils had no effect on copulation duration in any of the experiments. We discuss the possibility that the positive effect of grapefruit essential oils on wildish male competitiveness may have been linked to exposure of females to grapefruit as a larval food, which may have imprinted them with grapefruit odors during pupal eclosion and biased their response as adults to odors of their maternal host.

  20. 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

    2014-06-10

    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.

  1. Cross-sectional study of male sexual function in bariatric patients

    PubMed Central

    Bielecka, Ilona; Kwiatkowski, Andrzej; Janik, Piotr E.; Drazba, Thomas; Bujok, Jan; Stanowski, Edward; Paśnik, Krzysztof

    2016-01-01

    Introduction Obesity is associated with numerous comorbidities and affects various aspects of life, including sexual functioning. Bariatric surgery is an effective treatment for obese people. Male sexual function after bariatric surgery is not well known. Aim To compare male sexual function and sexual quality of life after surgical weight loss with controls seeking bariatric surgery. Material and methods International Index of Erectile Function and Sexual Quality of Life-Male (SQoL-M) questionnaires were administered by e-mail to 152 men who had undergone weight-loss surgery. The control group consisted of 44 obese men who completed the questionnaires during their preoperative evaluation. Results Fifty-six percent of men in the control group and 20% of men in the postoperative group reported erectile dysfunction (ED) (OR = 5.1; 95% CI: 1.6–16.0, p = 0.005). The median (Q1, Q3) total International Index of Erectile Function (IIEF) score did not show a significant difference between the control (62.0 (37.5, 66.5)) and postoperative groups (67.0 (57.0, 70.0)). However, median scores in domains of erectile function (EF), sexual desire (SD), and overall satisfaction (OS) were significantly higher in the postoperative group. The median SQoL-M was significantly higher (81.8 (51.5, 89.4) vs. 88.6 (84.8, 90.9); p < 0.05) in the postoperative group. Conclusions A lower prevalence of erectile dysfunction and better sexual quality of life were observed in the patients after surgical weight loss. The improvement in male sexual function may be considered as an advantage of bariatric surgery. PMID:27829940

  2. Sexual orientation of female-to-male transsexuals: a comparison of homosexual and nonhomosexual types.

    PubMed

    Chivers, M L; Bailey, J M

    2000-06-01

    Homosexual and nonhomosexual (relative to genetic sex) female-to-male transsexuals (FTMs) were compared on a number of theoretically or empirically derived variables. Compared to nonhomosexual FTMs, homosexual FTMs reported greater childhood gender nonconformity, preferred more feminine partners, experienced greater sexual rather than emotional jealousy, were more sexually assertive, had more sexual partners, had a greater desire for phalloplasty, and had more interest in visual sexual stimuli. Homosexual and nonhomosexual FTMs did not differ in their overall desire for masculinizing body modifications, adult gender identity, or importance of partner social status, attractiveness, or youth. These findings indicate that FTMs are not a homogeneous group and vary in ways that may be useful in understanding the relation between sexual orientation and gender identity.

  3. Methamphetamine acts on subpopulations of neurons regulating sexual behavior in male rats

    PubMed Central

    Frohmader, Karla S.; Wiskerke, Joost; Wise, Roy A.; Lehman, Michael N.; Coolen, Lique M.

    2010-01-01

    Methamphetamine (Meth) is a highly addictive stimulant. Meth abuse is commonly associated with the practice of sexual risk behavior and increased prevalence of Human Immunodeficiency Virus and Meth users report heightened sexual desire, arousal, and sexual pleasure. The biological basis for this drug-sex nexus is unknown. The current study demonstrates that Meth administration in male rats activates neurons in brain regions of the mesolimbic system that are involved in the regulation of sexual behavior. Specifically, Meth and mating co-activate cells in the nucleus accumbens core and shell, basolateral amygdala, and anterior cingulate cortex. These findings illustrate that in contrast to current belief drugs of abuse can activate the same cells as a natural reinforcer, i.e. sexual behavior, and in turn may influence compulsive seeking of this natural reward. PMID:20045448

  4. Treatment of sexual dysfunctions in male-only groups: predicting outcome.

    PubMed

    Dekker, J; Dronkers, J; Staffeleu, J

    1985-01-01

    Forty men complaining of sexual dysfunctions were treated in male-only groups, using RET, masturbation exercises and social skills training. Sexual functioning improved and social anxiety decreased. Combining these data with previously reported data on 21 men, we tried to predict treatment outcome. Sexual functioning of men with a steady partner and men with varying partners improved; in men without partner(s) no effect could be demonstrated, probably due to a methodological artifact. Inhibited sexual desire was associated with a poor outcome. Several other variables (among them type of dysfunction, social anxiety, age, educational level) did not predict improvement of sexual functioning. This method seems to provide adequate treatment for various complaints of men with quite different backgrounds.

  5. Criminal diversity and paraphilic interests among adult males convicted of sexual offenses against children.

    PubMed

    Smallbone, Stephen W; Wortley, Richard K

    2004-04-01

    Official demographic and offense history data (n = 362) and confidential self-report data on paraphilic interests and behavior (n = 221) obtained on adult males convicted of sexual offenses against children were analyzed. Considerable criminal diversity was observed, with all standard categories of offenses represented in offenders' criminal histories. Most (86%) of the offenders' previous convictions were for nonsexual offenses, and most (92%) of the recidivist offenders had previously been convicted of at least one nonsexual offense. The prevalence of diagnosable paraphilias was low, with only 5% meeting formal diagnostic criteria for multiple (two or more) paraphilias other than pedophilia. Sexual offenders' paraphilic interests were unrelated to the extent of their sexual offense convictions but were significantly related to the extent of their nonsexual offense convictions. The results are better explained by a general theory of crime than by traditional clinical conceptions linking sexual offenses specifically with sexual psychopathology.

  6. Sexual affordances, perceptual-motor invariance extraction and intentional nonlinear dynamics: sexually deviant and non-deviant patterns in male subjects.

    PubMed

    Renaud, Patrice; Goyette, Mathieu; Chartier, Sylvain; Zhornitski, Simon; Trottier, Dominique; Rouleau, Joanne-L; Proulx, Jean; Fedoroff, Paul; Bradford, John-P; Dassylva, Benoit; Bouchard, Stephane

    2010-10-01

    Sexual arousal and gaze behavior dynamics are used to characterize deviant sexual interests in male subjects. Pedophile patients and non-deviant subjects are immersed with virtual characters depicting relevant sexual features. Gaze behavior dynamics as indexed from correlation dimensions (D2) appears to be fractal in nature and significantly different from colored noise (surrogate data tests and recurrence plot analyses were performed). This perceptual-motor fractal dynamics parallels sexual arousal and differs from pedophiles to non-deviant subjects when critical sexual information is processed. Results are interpreted in terms of sexual affordance, perceptual invariance extraction and intentional nonlinear dynamics.

  7. Female Sexual Dysfunction Among the Wives of Opioid-Dependent Males in Iran

    PubMed Central

    Anvar Abnavi, Marjan; Ahmadi, Jamshid; Hamidian, Sajedeh; Ghaffarpour, Sara

    2016-01-01

    Background Opiate abuse in males has significant effects on their sexual functions. In contrast, sexuality in females is a multidimensional issue that can strongly be affected by several factors in their partners. However, only a limited number of studies have assessed the role of males’ opioid dependency in their female partners’ sexual function. Objectives The present study aimed to evaluate the effect of males’ opioid dependency on their wives’ sexual function compared to the sexual function of the females whose husbands were not opioid dependent. Patients and Methods This study included 340 women who were selected through convenience sampling and divided into a control (females whose husbands were not opioid dependent) and a case group (women whose husbands were opioid dependent). The data were collected through an interview according to the DSM-IV-R criteria for female sexual dysfunctions by a senior female medical student who was one of the researchers. Finally, the data were entered into the SPSS statistical software (v. 15) and analyzed using the t-test and chi-square test. Results According to the results, the frequency of hypoactive sexual desire disorder and sexual aversion disorder in the control group was significantly higher than that of the case group (P < 0.05). Conclusions The results showed that having an addicted husband could strongly affect some sexual domains in women. It could change the pattern of desire and motivation for sexual contact in females and alter their attitude toward the sexual relationship, thereby causing disturbances in the females’ normal sexual function. PMID:27218067

  8. POLYPRENOL REDUCTASE2 Deficiency Is Lethal in Arabidopsis Due to Male Sterility[OPEN

    PubMed Central

    Gutkowska, Malgorzata; Buczkowska, Anna; Lichocka, Malgorzata; Nowakowska, Julita

    2015-01-01

    Dolichol is a required cofactor for protein glycosylation, the most common posttranslational modification modulating the stability and biological activity of proteins in all eukaryotic cells. We have identified and characterized two genes, PPRD1 and -2, which are orthologous to human SRD5A3 (steroid 5α reductase type 3) and encode polyprenol reductases responsible for conversion of polyprenol to dolichol in Arabidopsis thaliana. PPRD1 and -2 play dedicated roles in plant metabolism. PPRD2 is essential for plant viability; its deficiency results in aberrant development of the male gametophyte and sporophyte. Impaired protein glycosylation seems to be the major factor underlying these defects although disturbances in other cellular dolichol-dependent processes could also contribute. Shortage of dolichol in PPRD2-deficient cells is partially rescued by PPRD1 overexpression or by supplementation with dolichol. The latter has been discussed as a method to compensate for deficiency in protein glycosylation. Supplementation of the human diet with dolichol-enriched plant tissues could allow new therapeutic interventions in glycosylation disorders. This identification of PPRD1 and -2 elucidates the factors mediating the key step of the dolichol cycle in plant cells which makes manipulation of dolichol content in plant tissues feasible. PMID:26628744

  9. [Sexual motivation in male mice induced by the presence of the female].

    PubMed

    Popova, N K; Amstislavskaia, T G; Kucheriavyĭ, S A

    1998-01-01

    Receptive female mouse placed in a cage behind a partition which prevented physical contacts but allowed the female to be smelt and seen produced in CBA and A/He males an elevation of plasma testosterone level and increase in time spent near the partition (TSNP) in attempts to reach the female. Both in CBA and A/He males the TSNP was much higher than in controls with empty adjacent compartment or with a male in it. The number of approaches to the partition was also increased but not sex-depended reflecting the general motor excitement of animals. A 3-4-fold increase in the TSNP preceding blood testosterone elevation was found within the first 10 min of female exposure. It was suggested that sexual motivation in males induced by female exposure was not caused by testosterone increase. The TSNP in male mice produced by female exposure can be used as an adequate index of sexual motivation.

  10. Effects of swimming activity on the copulatory behavior of sexually active male rats.

    PubMed

    Allouh, M Z

    2015-01-01

    Physical activity has long been associated with better sexual function. This study investigated the effects of moderate swimming exercise on the copulatory behavior of sexually potent male rats. Two sets of sexually potent male rats -highly active and moderately active- were identified depending on baseline sexual activity. Each of the two sets of rats was further randomly divided into two groups (swimming and sedentary). There were 16 rats in each of the four study groups (highly active swimming, highly active sedentary, moderately active swimming and moderately active sedentary). The copulatory behavior parameters and serum testosterone levels were measured and compared between the rats of the swimming and sedentary groups following a month long training period in which rats were made to swim for 1 h every alternate day. Swimming significantly improved the sexual performance of highly active rats, as indicated by increased intromission frequency and intromission ratio, compared with the sedentary controls. Swimming improved both sexual desire and performance, as indicated by reduced mount latency and increased intromission ratio, respectively, in swimming moderately active rats compared with the sedentary moderately active controls. Therefore, swimming activity improves the copulatory behavior of both highly active and moderately active male rats.

  11. Relational challenges and recovery processes in male survivors of childhood sexual abuse.

    PubMed

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

    2010-04-01

    Male survivors of childhood sexual abuse face challenges resolving sexual victimization experiences with the ideals of masculinity, often experiencing intimacy problems, emotional discomfort, alienation, and anger. Little attention has been paid to how male survivors learn to develop long-term connections, disclose emotions in relationship contexts, and negotiate intimacy. The current qualitative study of 16 adult male survivors of childhood sexual abuse, examined the relational challenges and the processes by which these survivors improved their capacity for seeking and participating in supportive relationships over time. Several mechanisms associated with positive adaptation were identified in their narratives, including engaging in safe relationships; gaining a sense of belonging by locating a community of others with shared experiences; learning healthy ways to manage relationships through setting boundaries, controlling anger, building trust, and developing intimacy; and achieving acceptance. Clinical implications and future directions for research and intervention are presented.

  12. 7 alpha-methyl-19-nortestosterone facilitates sexual behavior in the male Syrian hamster.

    PubMed

    Wood, R I; Bean, A R; Sundaram, K; Kumar, N; Bardin, C W

    1996-06-01

    Steroid hormones from the testes promote attraction to estrous females and facilitate copulation in the male Syrian hamster. We compared the ability of testosterone (T) and MENT, a potent synthetic androgen that does not undergo 5 alpha-reduction, to maintain sexual behavior in castrated males. Steroid treatment was initiated immediately after castration at three levels by means of Alzet osmotic pumps in sexually experienced adult male hamsters. Daily doses were 5, 25, or 100 micrograms T and 1, 5, or 25 micrograms MENT (n = 5/group). Additional castrated males (n = 5) remained untreated. Sexual behavior was recorded during two 10-min tests before, and at 2, 4, 6, and 8 weeks after orchidectomy. MENT and T maintained equivalent levels of behavior at each corresponding dose of androgen (high, medium, or low). The low dose of T or MENT failed to sustain mating behavior. Eight weeks after castration, males receiving the high and medium doses of androgens continued to express intromissions and ejaculations at gonadally intact levels. However, only males receiving the high dose showed anogenital investigation at the same level as intact males. From these data, we conclude that MENT sustains mating behavior in the male hamster, and that chemoinvestigatory behavior requires higher levels of androgens than those necessary for copulation.

  13. Nutritional correlates and mate acquisition role of multiple sexual traits in male collared flycatchers

    NASA Astrophysics Data System (ADS)

    Hegyi, Gergely; Szöllősi, Eszter; Jenni-Eiermann, Susanne; Török, János; Eens, Marcel; Garamszegi, László Zsolt

    2010-06-01

    The information content of a sexual signal may predict its importance in a multiple signal system. Many studies have correlated sexual signal expression with the absolute levels of nutrient reserves. In contrast, the changes of nutrient reserves associated with signal expression are largely unknown in the wild due to technical limitations although they are important determinants of signal information content. We compared two visual and eight acoustic sexual traits in male collared flycatchers to see whether the nutritional correlates of expression predict the role of the signal in sexual selection. We used single point assays of plasma lipid metabolites to estimate short-term changes in nutritional state in relation to sexual trait expression during courtship. As a measure of sexual selection, we estimated the relationship with pairing latency after arrival in a 4-year dataset. Males which found a mate rapidly were characterized by large wing and forehead patches, but small song strophe complexity and small figure repertoire size. Traits more strongly related to pairing latency were also more closely related to changes in nutrient reserves. This indicates a link between signal role and information content. Small wing patches and, surprisingly, complex songs seemed to indicate poor phenotypic quality and were apparently disfavoured at mate acquisition in our population. Future studies of the information content of sexual traits, especially dynamic traits such as song, may benefit from the use of plasma metabolite profiles as non-invasive indicators of short-term changes in body condition.

  14. Evaluation of the aphrodisiac activity of Tribulus terrestris Linn. in sexually sluggish male albino rats

    PubMed Central

    Singh, Surender; Nair, Vinod; Gupta, Yogendra K.

    2012-01-01

    Objectives: To study the effect of acute and repeated dose administration of lyophilized aqueous extract of the dried fruits of Tribulus terrestris (LAET) on sexual function in sexually sluggish male albino rats. Materials and Methods: Aphrodisiac activity of the test drug was evaluated in terms of exhibited sexual behavior. In order to assess the effect of chronic T. terrestris exposure on the hypothalamus--pituitary--gonadal axis, testosterone level estimation and sperm count were carried out. Twenty-eight-day oral toxicity studies were carried out to evaluate the long-term effects of the LAET administration on different body systems. Results: A dose-dependent improvement in sexual behavior was observed with the LAET treatment as characterized by an increase in mount frequency, intromission frequency, and penile erection index, as well as a decrease in mount latency, intromission latency, and ejaculatory latency. The enhancement of sexual behavior was more prominent on chronic administration of LAET. Chronic administration of LAET produced a significant increase in serum testosterone levels with no significant effect on the sperm count. No overt body system dysfunctions were observed in 28-day oral toxicity study. Conclusions: Findings of the present study validate the traditional use of T. terrestris as a sexual enhancer in the management of sexual dysfunction in males. PMID:22368416

  15. Chelicerae as male grasping organs in scorpions: sexual dimorphism and associated behaviour.

    PubMed

    Carrera, Patricia C; Mattoni, Camilo I; Peretti, Alfredo V

    2009-01-01

    Specialised structures that enable males to grasp females during sexual interactions are highly susceptible to selection and thus diverge relatively rapidly over evolutionary time. These structures are often used to test hypotheses regarding sexual selection such as sexually antagonistic co-evolution and sexual selection by female choice. In the present study, we determine whether there is a relationship between a novel record of scorpion sexual dimorphism, the sexual dimorphism of chelicerae (CSD), and the presence of the mating behaviour termed "cheliceral grip" (CG). The presence of both traits in the order Scorpiones is also reviewed from a phylogenetic perspective. The results confirm a strong relationship between CSD and the presence of CG. The morphological and behavioural patterns associated with "CSD-CG" are opposed to the predictions postulated by the hypothesis of sexually antagonistic co-evolution. However, if the female shows resistance after the deposition of the spermatophore, the possibility that the male exerts pressure as a "cryptic form" of coercion to prevent the interruption of mating cannot be ruled out completely. Female choice by "mechanical fit" could be another explanation for some aspects of the CG's contact zone. The possibility that the "CG-CSD" complex has evolved under natural selection in order to ensure sperm transfer is also considered.

  16. 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

  17. 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.

  18. Plastidic phosphoglucomutase and ADP-glucose pyrophosphorylase mutants impair starch synthesis in rice pollen grains and cause male sterility

    PubMed Central

    Lee, Sang-Kyu; Eom, Joon-Seob; Hwang, Seon-Kap; Shin, Dongjin; An, Gynheung; Okita, Thomas W.; Jeon, Jong-Seong

    2016-01-01

    To elucidate the starch synthesis pathway and the role of this reserve in rice pollen, we characterized mutations in the plastidic phosphoglucomutase, OspPGM, and the plastidic large subunit of ADP-glucose (ADP-Glc) pyrophosphorylase, OsAGPL4. Both genes were up-regulated in maturing pollen, a stage when starch begins to accumulate. Progeny analysis of self-pollinated heterozygous lines carrying the OspPGM mutant alleles, osppgm-1 and osppgm-2, or the OsAGPL4 mutant allele, osagpl4-1, as well as reciprocal crosses between the wild type (WT) and heterozygotes revealed that loss of OspPGM or OsAGPL4 caused male sterility, with the former condition rescued by the introduction of the WT OspPGM gene. While iodine staining and transmission electron microscopy analyses of pollen grains from homozygous osppgm-1 lines produced by anther culture confirmed the starch null phenotype, pollen from homozygous osagpl4 mutant lines, osagpl4-2 and osagpl4-3, generated by the CRISPR/Cas system, accumulated small amounts of starch which were sufficient to produce viable seed. Such osagpl4 mutant pollen, however, was unable to compete against WT pollen successfully, validating the important role of this reserve in fertilization. Our results demonstrate that starch is mainly polymerized from ADP-Glc synthesized from plastidic hexose phosphates in rice pollen and that starch is an essential requirement for successful fertilization in rice. PMID:27588462

  19. Plastidic phosphoglucomutase and ADP-glucose pyrophosphorylase mutants impair starch synthesis in rice pollen grains and cause male sterility.

    PubMed

    Lee, Sang-Kyu; Eom, Joon-Seob; Hwang, Seon-Kap; Shin, Dongjin; An, Gynheung; Okita, Thomas W; Jeon, Jong-Seong

    2016-10-01

    To elucidate the starch synthesis pathway and the role of this reserve in rice pollen, we characterized mutations in the plastidic phosphoglucomutase, OspPGM, and the plastidic large subunit of ADP-glucose (ADP-Glc) pyrophosphorylase, OsAGPL4 Both genes were up-regulated in maturing pollen, a stage when starch begins to accumulate. Progeny analysis of self-pollinated heterozygous lines carrying the OspPGM mutant alleles, osppgm-1 and osppgm-2, or the OsAGPL4 mutant allele, osagpl4-1, as well as reciprocal crosses between the wild type (WT) and heterozygotes revealed that loss of OspPGM or OsAGPL4 caused male sterility, with the former condition rescued by the introduction of the WT OspPGM gene. While iodine staining and transmission electron microscopy analyses of pollen grains from homozygous osppgm-1 lines produced by anther culture confirmed the starch null phenotype, pollen from homozygous osagpl4 mutant lines, osagpl4-2 and osagpl4-3, generated by the CRISPR/Cas system, accumulated small amounts of starch which were sufficient to produce viable seed. Such osagpl4 mutant pollen, however, was unable to compete against WT pollen successfully, validating the important role of this reserve in fertilization. Our results demonstrate that starch is mainly polymerized from ADP-Glc synthesized from plastidic hexose phosphates in rice pollen and that starch is an essential requirement for successful fertilization in rice.

  20. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice

    PubMed Central

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E.; Qiang, Sheng

    2015-01-01

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China. PMID:26012494

  1. Transgenic mice with inactive alleles for procollagen N-proteinase (ADAMTS-2) develop fragile skin and male sterility.

    PubMed

    Li, S W; Arita, M; Fertala, A; Bao, Y; Kopen, G C; Långsjö, T K; Hyttinen, M M; Helminen, H J; Prockop, D J

    2001-04-15

    Transgenic mice were prepared with inactive alleles for procollagen N-proteinase (ADAMTS-2; where ADAMTS stands for a disintegrin and metalloproteinase with thrombospondin repeats). Homozygous mice were grossly normal at birth, but after 1-2 months they developed thin skin that tore after gentle handling. Although the gene was inactivated, a large fraction of the N-propeptides of type I procollagen in skin and the N-propeptides of type II procollagen in cartilage were cleaved. Therefore the results suggested the tissues contained one or more additional enzymes that slowly process the proteins. Electron microscopy did not reveal any defects in the morphology of collagen fibrils in newborn mice. However, in two-month-old mice, the collagen fibrils in skin were seen as bizarre curls in cross-section and the mean diameters of the fibrils were approx. half of the controls. Although a portion of the N-propeptides of type II procollagen in cartilage were not cleaved, no defects in the morphology of the fibrils were seen by electron microscopy or by polarized-light microscopy. Female homozygous mice were fertile, but male mice were sterile with a marked decrease in testicular sperm. Therefore the results indicated that ADAMTS-2 plays an essential role in the maturation of spermatogonia.

  2. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice.

    PubMed

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E; Qiang, Sheng

    2015-05-27

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China.

  3. Binding of host-selective toxin analogs to mitochondria from normal and Texas male sterile cytoplasm maize

    SciTech Connect

    Frantzen, K.A.; Daly, J.M.; Knoche, H.W.

    1987-04-01

    Tritium-labeled toxin analogs were prepared by reduction with NaB/sup 3/H/sub 4/ of either the toxin from Helminthosporium maydis race T or a toxin component from Phyllosticta maydis. These reduced analogs had high radiochemical specific activities, high biological activities, and plant specificities identical to the native toxins. A filtration assay was developed to test the binding of these labeled analogs to isolated mitochondria. Binding was not energy dependent nor was there measurable matrical uptake. The analogs were shown to be lipophilic, a characteristic which gave rise to considerable nondisplaceable binding. Under conditions limiting nondisplaceable binding, the displaceable binding was shown to be linear with respect to toxin concentration and unsaturable. No significant differences were observed in the binding characteristics between the mitochondria from normal and male-sterile (Texas) cytoplasm maize. The findings suggest that, at physiologically relevant concentrations, these toxin analogs permeate the membranes of susceptible and resistant mitochondria alike. The lack of demonstrable specific binding does not rule out the involvement of a classical receptor site but does indicate that other kinds of molecular interactions may be involved in the mechanisms for toxicity and specificity.

  4. Arabidopsis MALE STERILITY1 encodes a PHD-type transcription factor and regulates pollen and tapetum development.

    PubMed

    Ito, Takuya; Nagata, Noriko; Yoshiba, Yoshu; Ohme-Takagi, Masaru; Ma, Hong; Shinozaki, Kazuo

    2007-11-01

    The Arabidopsis thaliana MALE STERILITY1 (MS1) gene encodes a nuclear protein with Leu zipper-like and PHD-finger motifs and is important for postmeiotic pollen development. Here, we examined MS1 function using both cell biological and molecular biological approaches. We introduced a fusion construct of MS1 and a transcriptional repression domain (MS1-SRDX) into wild-type Arabidopsis, and the transgenic plants showed a semisterile phenotype similar to that of ms1. Since the repression domain can convert various kinds of transcriptional activators to dominant repressors, this suggested that MS1 functioned as a transcriptional activator. The Leu zipper-like region and the PHD motif were required for the MS1 function. Phenotypic analysis of the ms1 mutant and the MS1-SRDX transgenic Arabidopsis indicated that MS1 was involved in formation of pollen exine and pollen cytosolic components as well as tapetum development. Next, we searched for MS1 downstream genes by analyzing publicly available microarray data and identified 95 genes affected by MS1. Using a transgenic ms1 plant showing dexamethasone-inducible recovery of fertility, we further examined whether these genes were immediately downstream of MS1. From these results, we discuss a role of MS1 in pollen and tapetum development and the conservation of MS1 function in flowering plants.

  5. Identification of tapetum-specific genes by comparing global gene expression of four different male sterile lines in Brassica oleracea.

    PubMed

    Ma, Yuan; Kang, Jungen; Wu, Jian; Zhu, Yingguo; Wang, Xiaowu

    2015-04-01

    The tapetum plays an important role in anther development by providing necessary enzymes and nutrients for pollen development. However, it is difficult to identify tapetum-specific genes on a large-scale because of the difficulty of separating tapetum cells from other anther tissues. Here, we reported the identification of tapetum-specific genes by comparing the gene expression patterns of four male sterile (MS) lines of Brassica oleracea. The abortive phenotypes of the four MS lines revealed different defects in tapetum and pollen development but normal anther wall development when observed by transmission electron microscopy. These tapetum displayed continuous defective characteristics throughout the anther developmental stages. The transcriptome from flower buds, covering all anther developmental stages, was analyzed and bioinformatics analyses exploring tapetum development-related genes were performed. We identified 1,005 genes differentially expressed in at least one of the MS lines and 104 were non-pollen expressed genes (NPGs). Most of the identified NPGs were tapetum-specific genes considering that anther walls were normally developed in all four MS lines. Among the 104 NPGs, 22 genes were previously reported as being involved in tapetum development. We further separated the expressed NPGs into different developmental stages based on the MS defects. The data obtained in this study are not only informative for research on tapetum development in B. oleracea, but are also useful for genetic pathway research in other related species.

  6. [Social representations of male sterilization. Vasectomy as viewed by professional counselors at the Men's Clinic in Bogotá,Colombia

    PubMed

    Viveros; Gomez; Otero

    1998-03-30

    Vasectomy service providers at the Clínica del Hombre (Men's Clinic) in Bogotá, Colombia, construct their representations concerning male sterilization on the basis of biomedical discourse, their interaction with clinic users, and their own life experiences. During provision of such services, the counselors are the health professionals who have the closest contact with these clients of the clinic. Counselors are in charge of exploring their motivations in requesting the service, in addition to providing information allowing them to take a calm, sound decision. They also directly filter demand based on their experience, knowledge, and skills, in permanent negotiation between institutional criteria (number of children and gap between them, client's age, steadiness of couple's relationship, and conviction concerning the decision), and their perception and assessment of the client. An analysis of the counselors' representations of decision-making as pertaining to vasectomy indicates that it is a relatively simple and harmless procedure as well as a liberating option in terms of family planning.

  7. Complex I impairment, respiratory compensations, and photosynthetic decrease in nuclear and mitochondrial male sterile mutants of Nicotiana sylvestris.

    PubMed

    Sabar, M; De Paepe, R; de Kouchkovsky, Y

    2000-11-01

    We have previously shown that in Nicotiana sylvestris cytoplasmic male-sterile (CMS) mutants where the mtDNA lacks the nad7 gene coding for a subunit of respiratory Complex I (NADH:ubiquinone oxidoreductase, EC 1.6.5.3), glycine (Gly) oxidation was lower than in the wild type and insensitive to rotenone, suggesting Complex I dysfunction. In contrast, the oxidation rate of exogenous NADH and the capacity of the cyanide-resistant respiration (AOX) were enhanced. Here we report that, in contrast to Gly, the rate of malate oxidation was not affected, but proceeded totally in a rotenone-insensitive pathway, strongly suggesting that survival of CMS plants depends on the activation of internal and external alternative NAD(P) H dehydrogenases and that Gly decarboxylase activity depends on Complex I functioning. A similar defect in Complex I activity and Gly oxidation was found in the NMS1 nuclear mutant, defective in the processing of the nad4 transcript, but alternative NAD(P) H dehydrogenases were less activated. In CMS and NMS1, the fraction of the AOX pathway was increased, as compared to wild type, associated with higher amounts of aox transcripts, AOX protein, and plant resistance to cyanide. Non-phosphorylating respiratory enzymes maintained normal in vivo respiration levels in both mutants, but photosynthesis was decreased, in correlation with lower leaf conductance, emphasizing mitochondrial control on photosynthesis.

  8. Self-efficacy, male rape myth acceptance, and devaluation of emotions in sexual trauma sequelae: Findings from a sample of male veterans.

    PubMed

    Voller, Emily; Polusny, Melissa A; Noorbaloochi, Siamak; Street, Amy; Grill, Joseph; Murdoch, Maureen

    2015-11-01

    Sexual trauma is an understudied but regrettably significant problem among male Veterans. As in women, sexual trauma often results in serious mental health consequences for men. Therefore, to guide potential future interventions in this important group, we investigated associations among self-efficacy, male rape myth acceptance, devaluation of emotions, and psychiatric symptom severity after male sexual victimization. We collected data from 1,872 Gulf War era Veterans who applied for posttraumatic stress disorder (PTSD) disability benefits using standard mailed survey methods. The survey asked about history of childhood sexual abuse, sexual assault during the time of Gulf War I, and past-year sexual assault as well as Veterans' perceived self-efficacy, male rape myth acceptance, devaluation of emotions, PTSD, and depression symptoms. Structural equation modeling revealed that self-efficacy partially mediated the association between participants' sexual trauma history and psychiatric symptoms. Greater male rape myth acceptance and greater devaluation of emotions were directly associated with lower self-efficacy, but these beliefs did not moderate associations between sexual trauma and self-efficacy. In this population, sexual trauma, male rape myth acceptance, and devaluation of emotions were associated with lowered self-efficacy, which in turn was associated with more severe psychiatric symptoms. Implications for specific, trauma-focused treatment are discussed.

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

    NASA Astrophysics Data System (ADS)

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

    1983-06-01

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

  10. Developmental Environment Effects on Sexual Selection in Male and Female Drosophila melanogaster

    PubMed Central

    Morimoto, Juliano; Pizzari, Tommaso; Wigby, Stuart

    2016-01-01

    The developmental environment can potentially alter the adult social environment and influence traits targeted by sexual selection such as body size. In this study, we manipulated larval density in male and female Drosophila melanogaster, which results in distinct adult size phenotypes–high (low) densities for small (large) adults–and measured sexual selection in experimental groups consisting of adult males and females from high, low, or a mixture of low and high larval densities. Overall, large adult females (those reared at low larval density) had more matings, more mates and produced more offspring than small females (those reared at high larval density). The number of offspring produced by females was positively associated with their number of mates (i.e. there was a positive female Bateman gradient) in social groups where female size was experimentally varied, likely due to the covariance between female productivity and mating rate. For males, we found evidence that the larval environment affected the relative importance of sexual selection via mate number (Bateman gradients), mate productivity, paternity share, and their covariances. Mate number and mate productivity were significantly reduced for small males in social environments where males were of mixed sizes, versus social environments where all males were small, suggesting that social heterogeneity altered selection on this subset of males. Males are commonly assumed to benefit from mating with large females, but in contrast to expectations we found that in groups where both the male and female size varied, males did not gain more offspring per mating with large females. Collectively, our results indicate sex-specific effects of the developmental environment on the operation of sexual selection, via both the phenotype of individuals, and the phenotype of their competitors and mates. PMID:27167120

  11. Sohlh2 knockout mice are male-sterile because of degeneration of differentiating type A spermatogonia.

    PubMed

    Hao, Jing; Yamamoto, Miwako; Richardson, Timothy E; Chapman, Karen M; Denard, Bray S; Hammer, Robert E; Zhao, Guang Quan; Hamra, F Kent

    2008-06-01

    The spermatogenesis and oogenesis-specific transcription factor Sohlh2 is normally expressed only in premeiotic germ cells. In this study, Sohlh2 and several other germ cell transcripts were found to be induced in mouse embryonic stem cells when cultured on a feeder cell line that overexpresses bone morphogenetic protein 4. To study the function of Sohlh2 in germ cells, we generated mice harboring null alleles of Sohlh2. Male Sohlh2-deficient mice were infertile because of a block in spermatogenesis. Although normal prior to birth, Sohlh2-null mice had reduced numbers of intermediate and type B spermatogonia by postnatal day 7. By day 10, development to the preleptotene spermatocyte stage was severely disrupted, rendering seminiferous tubules with only Sertoli cells, undifferentiated spermatogonia, and degenerating colonies of differentiating spermatogonia. Degenerating cells resembled type A2 spermatogonia and accumulated in M-phase prior to death. A similar phenotype was observed in Sohlh2-null mice on postnatal days 14, 21, 35, 49, 68, and 151. In adult Sohlh2-mutant mice, the ratio of undifferentiated type A spermatogonia (DAZL+/PLZF+) to differentiating type A spermatogonia (DAZL+/PLZF-) was twice normal levels. In culture, undifferentiated type A spermatogonia isolated from Sohlh2-null mice proliferated normally but linked the mutant phenotype to aberrant cell surface expression of the receptor-tyrosine kinase cKit. Thus, Sohlh2 is required for progression of differentiating type A spermatogonia into type B spermatogonia. One conclusion originating from these studies would be that testicular factors normally regulate the viability of differentiating spermatogonia by signaling through Sohlh2. This regulation would provide a crucial checkpoint to optimize the numbers of spermatocytes entering meiosis during each cycle of spermatogenesis. Disclosure of potential conflicts of interest is found at the end of this article.

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

    PubMed

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

    2013-01-01

    The sexual health and rights needs of male sex workers in Nigeria remain poorly understood and served. Men who sell sex are at high risk of discrimination and violation because of laws criminalising same-sex activity and sex work. This paper examines the experiences, social circumstances, vulnerabilities and sexual hazards experienced by male sex workers in Nigeria. In-depth interviews were used to explore the experiences of six male sex workers who were selected by means of convenience sampling from among those who came for counselling. Findings reveal that economic disadvantage drives some men to engage in sex work and risky sexual behaviour. Subsequently, sex work may put their lives and health at risk as a result of violation by the police and clients, including ritual murder. Men's extreme vulnerability points to the need for appropriate interventions to improve well-being. Sexual health and rights programmes must identify ways of making male sex workers less vulnerable to abuse, and devise strategies for protecting their health and human rights, while empowering them economically to reduce their dependency on often risky sexual behaviour for livelihoods.

  13. Reduced expression of CTR1 gene modulated by mitochondria causes enhanced ethylene response in cytoplasmic male-sterile Brassica juncea.

    PubMed

    Liu, Xunyan; Yang, Xiaodong; Zhao, Xuan; Yang, Jinghua; Zhang, Mingfang

    2012-06-01

    We studied how mitochondria affect ethylene response via modulation of CTR1 expression in cytoplasmic male-sterile (CMS) Brassica juncea. The expression of CTR1 gene was reduced in CMS compared with male-fertile (MF) lines. We observed that hypocotyl and root lengths were shorter than in the MF line during germination in the dark. An enhanced ethylene response was observed in CMS plants as shown by the CMS and maintainer line phenotypes treated with 1-aminocyclopropane-1-carboxylic acid. The phenotype in CMS plants could be recovered to the maintainer line when treated with Ag(+) . One ethylene response gene, plant defensin gene, was detected to be induced in CMS. The behavior of this phenotype could be mimicked by treating the maintainer line with antimycin A that disturbs mitochondrial function, which showed reduced length of hypocotyl and roots, and resulted in similar expression patterns of ethylene-related genes as in CMS. The reduced length of hypocotyl and roots could be recovered to the maintainer line by treatment with gibberellic acid (GA(3) ). In addition, the GA(3) content was reduced in CMS plants and in the MF line treated with antimycin A. Ethylene treatment markedly affects GA(3) content; however, GA(3) did not significantly affect ethylene-related gene expression in regards to regulation of hypocotyl and root length, which suggests that ethylene acts upstream via gibberellin to regulate hypocotyls and root development. Taken together, our results suggest a link between mitochondrial modulation of the ethylene and gibberellin pathway that regulates the development of hypocotyl and roots.

  14. 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.

  15. Sexual Aggression Victimization and Perpetration among Male and Female College Students in Chile

    PubMed Central

    Schuster, Isabell; Krahé, Barbara; Ilabaca Baeza, Paola; Muñoz-Reyes, José A.

    2016-01-01

    Evidence on the prevalence of sexual aggression among college students is primarily based on studies from Western countries. In Chile, a South American country strongly influenced by the Catholic Church, little research on sexual aggression among college students is available. Therefore, the purpose of the present study was to examine the prevalence of sexual aggression victimization and perpetration since the age of 14 (the legal age of consent) in a sample of male and female students aged between 18 and 29 years from five Chilean universities (N = 1135), to consider possible gender differences, and to study the extent to which alcohol was involved in the reported incidents of perpetration and victimization. Sexual aggression victimization and perpetration was measured with a Chilean Spanish version of the Sexual Aggression and Victimization Scale (SAV-S), which includes three coercive strategies (use or threat of physical force, exploitation of an incapacitated state, and verbal pressure), three victim-perpetrator constellations (current or former partners, friends/acquaintances, and strangers), and four sexual acts (sexual touch, attempted sexual intercourse, completed sexual intercourse, and other sexual acts, such as oral sex). Overall, 51.9% of women and 48.0% of men reported at least one incident of sexual victimization, and 26.8% of men and 16.5% of women reported at least one incident of sexual aggression perpetration since the age of 14. For victimization, only few gender differences were found, but significantly more men than women reported sexual aggression perpetration. A large proportion of perpetrators also reported victimization experiences. Regarding victim-perpetrator relationship, sexual aggression victimization and perpetration were more common between persons who knew each other than between strangers. Alcohol use by the perpetrator, victim, or both was involved in many incidents of sexual aggression victimization and perpetration, particularly

  16. Male Sterile2 Encodes a Plastid-Localized Fatty Acyl Carrier Protein Reductase Required for Pollen Exine Development in Arabidopsis

    SciTech Connect

    Chen, W.; Shanklin, J.; Yu, X.-H.; Zhang, K.; Shi, J.; De Oliveira, S.; Schreiber, L.; Zhang, D.

    2011-10-01

    Male Sterile2 (MS2) is predicted to encode a fatty acid reductase required for pollen wall development in Arabidopsis (Arabidopsis thaliana). Transient expression of MS2 in tobacco (Nicotiana benthamiana) leaves resulted in the accumulation of significant levels of C16 and C18 fatty alcohols. Expression of MS2 fused with green fluorescent protein revealed that an amino-terminal transit peptide targets the MS2 to plastids. The plastidial localization of MS2 is biologically important because genetic complementation of MS2 in ms2 homozygous plants was dependent on the presence of its amino-terminal transit peptide or that of the Rubisco small subunit protein amino-terminal transit peptide. In addition, two domains, NAD(P)H-binding domain and sterile domain, conserved in MS2 and its homologs were also shown to be essential for MS2 function in pollen exine development by genetic complementation testing. Direct biochemical analysis revealed that purified recombinant MS2 enzyme is able to convert palmitoyl-Acyl Carrier Protein to the corresponding C16:0 alcohol with NAD(P)H as the preferred electron donor. Using optimized reaction conditions (i.e. at pH 6.0 and 30 C), MS2 exhibits a K{sub m} for 16:0-Acyl Carrier Protein of 23.3 {+-} 4.0 {mu}m, a V{sub max} of 38.3 {+-} 4.5 nmol mg{sup -1} min{sup -1}, and a catalytic efficiency/K{sub m} of 1,873 m{sup -1} s{sup -1}. Based on the high homology of MS2 to other characterized fatty acid reductases, it was surprising that MS2 showed no activity against palmitoyl- or other acyl-coenzyme A; however, this is consistent with its plastidial localization. In summary, genetic and biochemical evidence demonstrate an MS2-mediated conserved plastidial pathway for the production of fatty alcohols that are essential for pollen wall biosynthesis in Arabidopsis.

  17. Post-translational mechanisms are associated with fertility restoration of cytoplasmic male sterility in sugar beet (Beta vulgaris).

    PubMed

    Kitazaki, Kazuyoshi; Arakawa, Takumi; Matsunaga, Muneyuki; Yui-Kurino, Rika; Matsuhira, Hiroaki; Mikami, Tetsuo; Kubo, Tomohiko

    2015-07-01

    Genetic conflict between cytoplasmically inherited elements and nuclear genes arising from their different transmission patterns can be seen in cytoplasmic male sterility (CMS), the mitochondrion-encoded inability to shed functional pollen. CMS is associated with a mitochondrial open reading frame (ORF) that is absent from non-sterility inducing mitochondria (S-orf). Nuclear genes that suppress CMS are called restorer-of-fertility (Rf) genes. Post-transcriptional and translational repression of S-orf mediates the molecular action of Rf that encodes a class of RNA-binding proteins with pentatricopeptide repeat (PPR) motifs. Besides the PPR-type of Rfs, there are also non-PPR Rfs, but the molecular interactions between non-PPR Rf and S-orf have not been described. In this study, we investigated the interaction of bvORF20, a non-PPR Rf from sugar beet (Beta vulgaris), with preSatp6, the S-orf from sugar beet. Anthers expressing bvORF20 contained a protein that interacted with preSATP6 protein. Analysis of anthers and transgenic calli expressing a FLAG-tagged bvORF20 suggested the binding of preSATP6 to bvORF20. To see the effect of bvORF20 on preSATP6, which exists as a 250-kDa protein complex in CMS plants, signal bands of preSATP6 in bvORF20-expressing and non-expressing anthers were compared by immunoblotting combined with Blue Native polyacrylamide gel electrophoresis. The signal intensity of the 250-kDa band decreased significantly, and 200- and 150-kDa bands appeared in bvORF20-expressing anthers. Transgenic callus expressing bvORF20 also generated the 200- and 150-kDa bands. The 200-kDa complex is likely to include both preSATP6 and bvORF20. Post-translational interaction between preSATP6 and bvORF20 appears to alter the higher order structure of preSATP6 that may lead to fertility restoration in sugar beet.

  18. Coercive sexual experiences, protective behavioral strategies, alcohol expectancies and consumption among male and female college students.

    PubMed

    Palmer, Rebekka S; McMahon, Thomas J; Rounsaville, Bruce J; Ball, Samuel A

    2010-09-01

    Alcohol use and sexual assault on college campuses are highly prevalent and the focus of numerous prevention and intervention efforts. Our goals were to gain a greater understanding of the relationship between coercive sexual experiences, utilization of protective behavioral strategies and alcohol expectancies and consumption among male and female college students. We surveyed 370 college students regarding their past year experiences and found that 34% of women and 31% of men reported unwanted sexual contact, 6% of women and 13% of men reported engaging in sexually coercive behavior, and 4% of women and 9% of men reported experiencing both unwanted contact and engaging in sexually coercive behavior. Findings indicated students who experienced unwanted sexual contact reported significant differences in alcohol expectancies. More specifically, those who engaged in sexually coercive behaviors had significantly higher sex-related alcohol expectancies. In addition, recipients of unwanted contact reported higher alcohol consumption, used fewer protective strategies when drinking, and experienced more negative consequences due to their alcohol use. Results suggest that campus alcohol and sexual assault prevention efforts should include information on alcohol expectancies and use of protective strategies.

  19. Experimental evolution exposes female and male responses to sexual selection and conflict in Tribolium castaneum.

    PubMed

    Michalczyk, Łukasz; Millard, Anna L; Martin, Oliver Y; Lumley, Alyson J; Emerson, Brent C; Gage, Matthew J G

    2011-03-01

    Between-individual variance in potential reproductive rate theoretically creates a load in reproducing populations by driving sexual selection of male traits for winning competitions, and female traits for resisting the costs of multiple mating. Here, using replicated experimental evolution under divergent operational sex ratios (OSR, 9:1 or 1:6 ♀:♂) we empirically identified the parallel reproductive fitness consequences for females and males in the promiscuous flour beetle Tribolium castaneum. Our results revealed clear evidence that sexual conflict resides within the T. castaneum mating system. After 20 generations of selection, females from female-biased OSRs became vulnerable to multiple mating, and showed a steep decrease in reproductive fitness with an increasing number of control males. In contrast, females from male-biased OSRs showed no change in reproductive fitness, irrespective of male numbers. The divergence in reproductive output was not explained by variation in female mortality. Parallel assays revealed that males also responded to experimental evolution: individuals from male-biased OSRs obtained 27% greater reproductive success across 7-day competition for females with a control male rival, compared to males from the female-biased lines. Subsequent assays suggest that these differences were not due to postcopulatory sperm competitiveness, but to precopulatory/copulatory competitive male mating behavior.

  20. A novel epistatic interaction at two loci causing hybrid male sterility in an inter-subspecific cross of rice (Oryza sativa L.).

    PubMed

    Kubo, Takahiko; Yamagata, Yoshiyuki; Eguchi, Maki; Yoshimura, Atsushi

    2008-12-01

    Postzygotic reproductive isolation (RI) often arises in inter-subspecific crosses as well as inter-specific crosses of rice (Oryza sativa L.). To further understand the genetic architecture of the postzygotic RI, we analyzed genes causing hybrid sterility and hybrid breakdown in a rice inter-subspecific cross. Here we report hybrid male sterility caused by epistatic interaction between two novel genes, S24 and S35, which were identified on rice chromosomes 5 and 1, respectively. Genetic analysis using near-isogenic lines (NILs) carrying IR24 (ssp. indica) segments with Asominori (ssp. japonica) genetic background revealed a complicated aspect of the epistasis. Allelic interaction at the S24 locus in the heterozygous plants caused abortion of male gametes carrying the Asominori allele (S24-as) independent of the S35 genotype. On the other hand, male gametes carrying the Asominori allele at the S35 locus (S35-as) showed abortion only when the IR24 allele at the S24 locus (S24-ir) was concurrently introgressed into the S35 heterozygous plants, indicating that the sterility phenotype due to S35 was dependent on the S24 genotype through negative epistasis between S24-ir and S35-as alleles. Due to the interaction between S24 and S35, self-pollination of the double heterozygous plants produced pollen-sterile progeny carrying the S24-ir/S24-ir S35-as/S35-ir genotype in addition to the S24 heterozygous plants. This result suggests that the S35 gene might function as a modifier of S24. This study presents strong evidence for the importance of epistatic interaction as a part of the genetic architecture of hybrid sterility in rice. In addition, it suggests that diverse systems have been developed as postzygotic RI mechanisms within the rice.

  1. Identification of Amplified Fragment Length Polymorphism (AFLP) Markers Tightly Associated with Drought Stress Gene in Male Sterile and Fertile Salvia miltiorrhiza Bunge.

    PubMed

    Zhang, Yuejin; Guo, Lijun; Shu, Zhiming; Sun, Yiyue; Chen, Yuanyuan; Liang, Zongsuo; Guo, Hongbo

    2013-03-22

    Consistent grain yield in drought environment has attracted wide attention due to global climate change. However, the important drought-related traits/genes in crops have been rarely reported. Many near-isogenic lines (NILs) of male sterile and fertile Salvia miltiorrhiza have been obtained in our previous work through testcross and backcross in continuous field experiments conducted in 2006-2009. Both segregating sterile and fertile populations were subjected to bulked segregant analysis (BSA) and amplified fragment length polymorphism (AFLP) with 384 and 170 primer combinations, respectively. One out of 14 AFLP markers (E9/M3246) was identified in treated fertile population as tightly linked to the drought stress gene with a recombination frequency of 6.98% and at a distance of 7.02 cM. One of 15 other markers (E2/M5357) was identified in a treated sterile population that is closely associated with the drought stress gene. It had a recombination frequency of 4.65% and at a distance of 4.66 cM. Interestingly, the E9/M3246 fragment was found to be identical to another AFLP fragment E11/M4208 that was tightly linked to the male sterile gene of S. miltiorrhiza with 95% identity and e-value 4 × 10-93. Blastn analysis suggested that the drought stress gene sequence showed higher identity with nucleotides in Arabidopsis chromosome 1-5.

  2. Characterization of male killer whale (Orcinus orca) sexual maturation and reproductive seasonality.

    PubMed

    Robeck, T R; Monfort, S L

    2006-07-15

    Longitudinal serum testosterone concentrations (n=10 males) and semen production (n=2 males) in killer whales were evaluated to: (1) characterize fluctuations in serum testosterone concentrations with respect to reproductive maturity and season; (2) compare morphologic changes to estimated age of sexual maturity, based on changes in serum testosterone concentrations; and (3) evaluate seasonal changes in sperm production. Classification of reproductive status and age class was based on differences (P < 0.05) in serum testosterone concentrations according to age; juvenile males ranged from 1 to 7 years (mean+/-S.D. testosterone, 0.13+/-0.20 ng/mL), pubertal males from 8 to 12 years (2.88+/-3.20 ng/mL), and sexually mature animals were 13 years and older (5.57+/-2.90 ng/mL). For captive-born males, serum testosterone concentrations, total body length and height to width ratio of the dorsal fin were 0.7+/-0.7 ng/mL, 495.6+/-17.5 cm and 1.14+/-0.13c m, respectively, at puberty; at sexual maturity, these end points were 6.0+/-3.3 ng/mL, 548+/-20 cm and 1.36+/-0.1cm. Serum testosterone concentrations were higher (P<0.05) from March to June than from December to February in pubertal animals (4.2+/-3.4 ng/mL versus 1.4+/-2.6 ng/mL) and than from September to December in sexually mature animals (7.2+/-3.3 ng/mL versus 4.0+/-2.0 ng/mL). Ejaculates (n = 90) collected from two males had similar (P > 0.05) sperm concentrations across all months. These data represent the first comprehensive study on male testosterone concentrations during and after sexual maturation, and on reproductive seasonality in the killer whale.

  3. Development of a novel recessive genetic male sterility system for hybrid seed production in maize and other cross-pollinating crops.

    PubMed

    Wu, Yongzhong; Fox, Tim W; Trimnell, Mary R; Wang, Lijuan; Xu, Rui-Ji; Cigan, A Mark; Huffman, Gary A; Garnaat, Carl W; Hershey, Howard; Albertsen, Marc C

    2016-03-01

    We have developed a novel hybridization platform that utilizes nuclear male sterility to produce hybrids in maize and other cross-pollinating crops. A key component of this platform is a process termed Seed Production Technology (SPT). This process incorporates a transgenic SPT maintainer line capable of propagating nontransgenic nuclear male-sterile lines for use as female parents in hybrid production. The maize SPT maintainer line is a homozygous recessive male sterile transformed with a SPT construct containing (i) a complementary wild-type male fertility gene to restore fertility, (ii) an α-amylase gene to disrupt pollination and (iii) a seed colour marker gene. The sporophytic wild-type allele complements the recessive mutation, enabling the development of pollen grains, all of which carry the recessive allele but with only half carrying the SPT transgenes. Pollen grains with the SPT transgenes exhibit starch depletion resulting from expression of α-amylase and are unable to germinate. Pollen grains that do not carry the SPT transgenes are nontransgenic and are able to fertilize homozygous mutant plants, resulting in nontransgenic male-sterile progeny for use as female parents. Because transgenic SPT maintainer seeds express a red fluorescent protein, they can be detected and efficiently separated from seeds that do not contain the SPT transgenes by mechanical colour sorting. The SPT process has the potential to replace current approaches to pollen control in commercial maize hybrid seed production. It also has important applications for other cross-pollinating crops where it can unlock the potential for greater hybrid productivity through expanding the parental germplasm pool.

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

    PubMed

    Katsulis, Yasmina; Durfee, Alesha

    2012-01-01

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