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1

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

Microsoft Academic Search

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

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

2001-01-01

2

Male Sterility  

Microsoft Academic Search

\\u000a The control of pollen fertility is central to the production of F1-hybrid seed in self-pollinating crops, and is potentially\\u000a applicable to the containment of transgenes deployed in crop plants. Pollen sterility can be achieved through cytoplasmic\\u000a male sterility (CMS) encoded by the plant mitochondrial genome, or through genic male sterility encoded by the nuclear genome.\\u000a Both routes have been exploited

C. D. Chase; A. Ribarits; E. Heberle-Bors

3

Gynodioecy in Plantago lanceolata L. III. Sexual reproduction and the maintenance of male steriles1  

Microsoft Academic Search

The importance of the reproductive part of the life cycle for the maintenance of the gynodioecious breeding system in Plantago lanceolata has been studied. Two male sterility types (MS1, MS2), the corresponding partial male sterility types or intermediates (IN1, IN2) and hermaphrodites (H) have been compared in four populations for seed production (ovule production [ ] female fertility) and weight

J M M Van Damme

1984-01-01

4

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

Microsoft Academic Search

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

Eyal Ben Ami; Boaz Yuval; Edouard Jurkevitch

2010-01-01

5

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

PubMed

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. PMID:19617877

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

2010-01-01

6

Sexual Selection: Male-Male Competition  

E-print Network

VII.5 Sexual Selection: Male-Male Competition Christine W. Miller It is certain that amongst almost often the competing sex and females the choosy sex? 2. The processes of sexual selection 3. Male-male competition in plants 7. Total sexual selection 8. Sexual selection and ecological context Males commonly

Miller, Christine Whitney

7

Male child sexual abuse.  

PubMed

Up to 92,000 male children report sexual abuse each year, and as many as 31% of all male children under age 18 years experience sexual molestation. Male child sexual abuse is now believed to be a far more common occurrence than it once was. Pediatric nurse practitioners are in a key position to prevent and recognize the sexual exploitation of male children. This article addresses the incidence of male child sexual abuse, the psychological and physical ramifications for the child, and the roles and responsibilities of the clinician, including interview, physical and psychological assessment, legal aspects of reporting, and referral. Prevention techniques in a primary care setting are also discussed. PMID:10531903

Moody, C W

1999-01-01

8

Post-Teneral Protein Feeding Improves Sexual Competitiveness But Reduces Longevity of Mass-Reared Sterile Male Mediterranean Fruit Flies (Diptera: Tephritidae)  

Microsoft Academic Search

The sterile insect technique is gaining an increasing role in the control of Mediter- ranean fruit fly, Ceratitis capitata (Wiedemann), populations. In the current study, we examine how post-teneral nutrition during the first 4—8 d after adult emergence affects performance and copu- latory success in leks of mass-reared sterile (TSL strain) males. We found that protein and sugar fed males

Roy Kaspi; Boaz Yuval

2000-01-01

9

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

PubMed Central

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

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

10

Male or female sterilization: a comparative study.  

PubMed

The study compares 709 males and 546 females recruited from a well-defined geographic area and sterilized during a 5-year period at the same hospital. Medical records were reviewed and questionnaires sent out. Widespread satisfaction with the sterilization was found. The sterilized women had experienced contraceptive side effects and failures more often than the men. Only 70% of the laparoscopic sterilizations could be carried out during a 1-day admission, 25% of the women complained about long-term sequelae, and there were 1% failures. The vasectomies were carried out on an outpatient basis, there were few postoperative symptoms, and 0.5% failures were recorded. Female sterilization was at least four times as expensive as vasectomy. It is concluded that vasectomy is generally to be preferred to female sterilization, and that the preoperative guidance should involve both man and wife. PMID:2920844

Kjersgaard, A G; Thranov, I; Rasmussen, O V; Hertz, J

1989-03-01

11

The Decision for Male versus Female Sterilization.  

ERIC Educational Resources Information Center

The increasing popularity of sterilization underscores the need for knowledge about couples choosing male and female procedures. This research delineates four sets of variables that may be important for the decision and examines their relationship with the choice of male or female procedure among a sample of married couples. (Author)

Clark, Margaret Pruitt; And Others

1979-01-01

12

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

PubMed Central

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

Kraaijeveld, Ken; Chapman, Tracey

2004-01-01

13

Suppression of Pest Lepidoptera by Releasing Partially Sterile Males  

ERIC Educational Resources Information Center

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…

Knipling. E. F.

1970-01-01

14

Male sexual dysfunction in Asia  

PubMed Central

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

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

2011-01-01

15

Comparative risks and costs of male and female sterilization.  

PubMed Central

Couples who are considering elective sterilization should compare the risks and costs of male and female sterilization procedures as part of the decision process. Morbidity, mortality, failure rates, and short-term costs associated with male and female sterilization procedures were estimated from data available in previous case series. Male sterilization procedures were found to have zero attributable deaths and significantly less major complications when compared to female sterilization procedures. No less than 14 deaths a year can be attributed to female sterilization procedures in the US. Male and female sterilization procedures have efficacy rates that are not significantly different from each other. The short-term costs of female sterilization are 3.0 to 4.1 times that of vasectomy. PMID:3976963

Smith, G L; Taylor, G P; Smith, K F

1985-01-01

16

Cytoplasmic male sterility in Brassicaceae crops  

PubMed Central

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. PMID:24987289

Yamagishi, Hiroshi; Bhat, Shripad R.

2014-01-01

17

Timing of callase activity and cytoplasmic male sterility in Petunia  

Microsoft Academic Search

A study of callase activity in relation to cytogenetical expressions in cytoplasmic male sterile and male fertile Petunia indicated differential timing of the localized enzyme activity. Enzyme activity was determined by a new test. The possible relations between the mode of action of the extrachromosomal gene, timing of the enzyme activity, and male sterility are discussed.

Rafael Frankel; Shamay Izhar; Joseph Nitsan

1969-01-01

18

Male sterility, fitness gain curves and the evolution of gender specialization from distyly in Erythroxylum havanense.  

PubMed

The evolution of dioecy from a monomorphic hermaphroditic condition requires two mutations, one producing females and one producing males. Conversely, a single mutation sterilizing one sexual function in one morph of distylous species would result in functional dioecy because such a mutation also affects the complementary function in the other morph. In this study, we tested these ideas with Erythroxylum havanense, a distylous species with morph-biased male sterility. Based on sex allocation theory we evaluated whether the invasion of thrum females is favoured over the maintenance of this morph cosexuals. Completely male sterile thrum plants obtained higher fitness returns than hermaphrodites or partial male sterile individuals of the same morph, thus favouring the invasion of female thrum plants. We concluded that because fruit production of pin individuals depends on the pollen produced by thrum plants, the invasion of thrum females would result on the evolution of functional dioecy. PMID:18811662

Rosas, F; Domínguez, C A

2009-01-01

19

Sexual satisfaction in male infertility.  

PubMed

Infertility is proposed to be a continuing stressor for couples suffering from involuntary childlessness. A long duration of the desire for a child and, correspondingly, a longer period of diagnostic and treatment procedures could have a negative impact on sexual satisfaction, thus leading to an unfavorable psychological circuit. The present evaluation should clarify the state of sexual satisfaction and relationships, with relevant parameters in 68 men with fertility problems, of couples with involuntary childlessness. Subjects reported relatively high average levels of present sexual satisfaction with only nonsignificant lower scores (p = .08) compared to recalled sexual satisfaction prior to diagnosis of infertility. Multiple regression analyses revealed that a positive age difference between men and their spouses (p = .042) and a higher weekly coitus frequency (p = .002) were the only significant parameters associated independently with higher sexual satisfaction. Neither the age of partners, attitudes toward sexuality, treatment duration, duration of the partnership and the duration of the desire for a child, nor andrological findings had an influence on present sexual satisfaction. The results propose that treatment duration and duration of the desire for a child may not necessarily be connected to lowered sexual satisfaction in infertile males and that coitus frequency seems to be an indicator of sexual satisfaction in this patient group. PMID:10407644

Müller, M J; Schilling, G; Haidl, G

1999-01-01

20

Gene, protein, and network of male sterility in rice  

PubMed Central

Rice is one of the most important model crop plants whose heterosis has been well-exploited in commercial hybrid seed production via a variety of types of male-sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and proteins related to cytoplasmic male sterility (CMS), photoperiod-sensitive male sterility, self-incompatibility, and other types of microspores deterioration have been characterized through genetics or proteomics. Especially the latter, offers us a powerful and high throughput approach to discern the novel proteins involving in male-sterile pathways which may help us to breed artificial male-sterile system. This represents an alternative tool to meet the critical challenge of further development of hybrid rice. In this paper, we reviewed the recent developments in our understanding of male sterility in rice hybrid production across gene, protein, and integrated network levels, and also, present a perspective on the engineering of male-sterile lines for hybrid rice production. PMID:23596452

Wang, Kun; Peng, Xiaojue; Ji, Yanxiao; Yang, Pingfang; Zhu, Yingguo; Li, Shaoqing

2013-01-01

21

Sexual stimulation in male sheep and goats  

Microsoft Academic Search

Previous research has shown that the sexual performance of male goats is enhanced by viewing the mating activities of other males prior to being placed with sexually receptive females. This same experience has no effect on the sexual performance of male sheep. In the present experiment, 14 male goats and 17 rams were individually allowed to sniff and nuzzle the

Edward O Price; Reid Borgwardt; Agustin Orihuela; Martin R Dally

1998-01-01

22

Mitochondria and cytoplasmic male sterility in plants.  

PubMed

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

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

2014-11-01

23

Evaluation of Male Sexual Dysfunction  

Microsoft Academic Search

\\u000a The management of male sexual dysfunction and specifically erectile dysfunction (ED) has seen major changes in each decade\\u000a since the 1970s thanks to the discovery that a papaverine injection could produce erection, the NIH Consensus Statement which\\u000a defined ED in 1992, advances in minimally invasive diagnostics, and the development of orally effective erectogenic class\\u000a of drugs, the phosphodiesterase type-5 inhibitors

Gregory A. Broderick

24

Anther developmental defects in Arabidopsis thaliana male-sterile mutants  

Microsoft Academic Search

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

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

1999-01-01

25

Sexual Selection in Males and Females  

E-print Network

Sexual Selection in Males and Females Tim Clutton-Brock Research on sexual selection shows involved. However, the operation of sexual selection in females has still received relatively little partners are common, leading to strong sexual selection in females and, in extreme cases, to reversals

Sorenson, Michael

26

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

Microsoft Academic Search

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

B. Yuval; M. Maor; K. Levy; R. Kaspi; P. Taylor; T. Shelly

2007-01-01

27

Amyloid ? precursor protein regulates male sexual behavior  

PubMed Central

Sexual behavior is variable between individuals, ranging from celibacy to sexual addictions. Within normal populations of individual men, ranging from young to middle aged, testosterone levels do not correlate with libido. To study the genetic mechanisms that contribute to individual differences in male sexual behavior, we used hybrid B6D2F1 male mice, which are a cross between two common inbred strains (C57BL/6J and DBA/2J). Unlike most laboratory rodent species in which male sexual behavior is highly dependent upon gonadal steroids, sexual behavior in a large proportion of these hybrid male mice after castration is independent of gonadal steroid hormones and their receptors; thus, we have the ability to discover novel genes involved in this behavior. Gene expression arrays, validation of gene candidates, and transgenic mice that over-express one of the genes of interest were utilized to reveal genes involved in maintenance of male sexual behavior. Several genes related to neuroprotection and neurodegeneration were differentially expressed in the hypothalamus of males that continued to mate after castration. Male mice over-expressing the human form of one of these candidate genes, amyloid beta precursor protein (APP), displayed enhanced sexual behavior prior to castration and maintained sexual activity for a longer duration after castration as compared with controls. Our results reveal a novel and unexpected relationship between APP and male sexual behavior. We speculate that declining APP during normal aging in males may contribute to the loss of sexual function. PMID:20668181

Park, Jin Ho; Bonthius, Paul; Tsai, Houng-Wei; Bekiranov, Stefan; Rissman, Emilie F.

2010-01-01

28

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

USGS Publications Warehouse

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.

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

2004-01-01

29

Reproductive Allocation and Resource Compensation in Male-Sterile and Hermaphroditic Plants of Plantago lanceolata (Plantaginaceae)  

Microsoft Academic Search

Gynodioecy is a breeding system in which hermaphrodites coexist with male steriles. Theoretical models predict that without any compensation in female fitness male steriles will disappear from a population due to their reproductive disad- vantage. In the present study I investigated whether male-sterile (MS), partially male-sterile (IN), and hermaphroditic (H) plants of Plantago lanceolata differed in reproductive growth and allocation.

Pieter Poot

1997-01-01

30

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

Microsoft Academic Search

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

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

2006-01-01

31

Sterilization.  

PubMed

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. PMID:18165410

Peterson, Herbert B

2008-01-01

32

The male victim of sexual assault.  

PubMed

Under-reporting by male victims is more pronounced than for females victims, and so male victims remain a rarity for most sexual assault aftercare service providers. In this chapter, I present a review of forensic medical and psycho-social literature on male-on-male rape and sexual assault. Where appropriate, comparison is made with female victims, as that is the context with which most aftercare service providers are familiar. The following aspects are covered: prevalence; definitions; social perceptions of perpetrators and victims of sexual assault on males; characteristics of victims and assaults; physiological and psychological responses; and implications for forensic medical investigation. PMID:22951768

McLean, Iain A

2013-02-01

33

Cytoplasmic male sterility-regulated novel microRNAs from maize.  

PubMed

In higher plants, microRNA (miRNA) is involved in regulation of developmental processes, including sexual organ development. Seven novel miRNA families with one known miRNA were isolated by constructing a small RNA library from a mixture of anther from a cytoplasmic male sterile line and its maintainer. Two miRNAs are conserved in plant species. A total of 18 potential targets were identified for the eight miRNA families, including 15 proteins annotated with function and three unknown proteins. The known proteins include several proteins relevant to cell structure and stress response, transcription factors, and enzymes associated with metabolic and signaling pathways, playing important roles in microspore development. Quantitative real-time PCR assay revealed different expression patterns of the miRNAs between the cytoplasmic male sterile line and its maintainer. Each of the miRNAs tended to be down-regulated after the tetrad stage in a fertile line. However, most of the miRNAs in the cytoplasmic male sterile line were shown to be up-regulated from the tetrad to mononuclear stage, displaying special expression patterns differing from the ones in fertile line. We conclude that additional inactive miRNA pathways are essential during pollen development for a fertile line to ensure male fertility. Contrarily, miRNAs are up-regulated during the period from the tetrad to mononuclear stage, which contributes to pollen abortion for a cytoplasmic male sterile line. PMID:21042925

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

2011-03-01

34

Sexuality of Male-to-Female Transsexuals  

Microsoft Academic Search

Blanchard’s (J Nerv Ment Dis 177:616–623, 1989) theory of autogynephilia suggests that male-to-female transsexuals can be\\u000a categorized into different types based on their sexuality. Little previous research has compared the sexuality of male-to-female\\u000a transsexuals to biological females. The present study examined 15 aspects of sexuality among a non-clinical sample of 234\\u000a transsexuals and 127 biological females, using either an online

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

2008-01-01

35

Males under attack: sexual cannibalism and its consequences for male morphology  

E-print Network

success, males may be under sexual selection through male­male competition, female choice and/or sexual behaviour in this group. Here, we investigate sexual selection on male body size, leg length and copulation, Argiope aurantia, copulation duration, sexual cannibalism, sexual selection, sexual size dimorphism, shape

Foellmer, Matthias

36

The molecular basis of cytoplasmic male sterility and fertility restoration  

Microsoft Academic Search

Cytoplasmic male sterility (CMS) is a maternally inherited condition in which a plant is unable to produce functional pollen. It occurs in many plant species and is often associated with chimeric mitochondrial open reading frames. In a number of cases, transcripts originating from these altered open reading frames are translated into unique proteins that appear to interfere with mitochondrial function

Patrick S Schnable; Roger P Wise

1998-01-01

37

Gynodioecy in plantago lanceolata L. II Inheritance of three male sterility types2  

Microsoft Academic Search

Inheritance of male sterility has been studied in Plantago lanceolata. Crosses between plants, obtained from a 50 m2 area, yielded the entire array of possible sex phenotypes. Emphasis is put on nuclear inheritance of two nuclear-cytoplasmically determined male sterility types. In both types multiple interacting genes are involved. For MS1 a combination of two recessive and three dominant male sterility

J M M van Damme

1983-01-01

38

Cytoplasmic Male Sterility in Barley. Xi. the msm2 Cytoplasm  

PubMed Central

A new cytoplasmic male sterility in barley (Hordeum vulgare s.l.) is described and designated as msm2. The cytoplasm was derived from a selection of the wild progenitor of barley (H. vulgare ssp. spontaneum). This selection, 79BS14-3, originates from the Southern Coastal Plain of Israel. The selection 79BS14-3 has a normal spike fertility in Finland. When 79BS14-3 was crossed by cv. Adorra, the F1 displayed partial male fertility and progeny of recurrent backcrosses with cv. Adorra were completely male sterile. Evidently 79BS14-3 is a carrier of a recessive or semidominant restorer gene of fertility. The dominant restorer gene Rfm1a for another cytoplasmic male sterility, msm1, is also effective in msm2 cytoplasm. The different partial fertility restoration properties of msm2 and msm1 cause these cytoplasms to be regarded as being distinct. Seventy spontaneum accessions from Israel have been studied for their capacity to produce F1 restoration of male fertility both in msm1 and in msm2 cytoplasms with a cv. Adorra-like seed parent (nuclear gene) background. The msm2 cytoplasm shows partial restoration more commonly than msm1 in these F1 combinations. The mean restoration percentage per accession for msm2 is 28, and for msm1 4. Most of the F1 seed set differences of the two cytoplasms are statistically significant. When estimated with partially restored F1 combinations, msm2 cytoplasm appeared to be about 50 times more sensitive to the male fertility-promoting genes present in the spontaneum accessions. The spontaneum sample from Central and Western Negev, which has been found to be devoid of restoration ability in msm1 cytoplasm, had only low partial restoration ability in msm2 (mean 0.3%). The female fertility of msm2 appears normal. The new msm2 cytoplasm could be useful in producing hybrid barley. PMID:17246095

Ahokas, H.

1982-01-01

39

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

E-print Network

Hybrid male sterility in rice controlled by interaction between divergent alleles of two adjacent hybrid sterility reproductive barrier two-gene/three-component model Hybrid sterility is the most common, Kobe, Japan, October 9, 2008 (received for review July 27, 2008) Sterility is common in hybrids between

Nachman, Michael

40

Cytoplasmic male sterility in Plantago lanceolata L.: differences between male-sterile cytoplasms at the DNA and RNA-level  

Microsoft Academic Search

To establish the feasibility of a cytoplasmtype assay based on molecular hybridizations, mitochondrial DNAs from the two male-sterile cytoplasms of Plantago lanceolata (P and R) were compared by restriction endonuclease digestion. We cloned a 1.1 kbp Eco RI-HindIII fragment from P-mtDNA (pPl-311), which on hybridization to Southern blots of Bam HI digested mtDNA and total DNA from plants with P-cytoplasm,

G. J. A. Rouwendal; J. M. M. Damme; J. G. H. Wessels

1987-01-01

41

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

PubMed

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

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

2007-06-01

42

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

PubMed Central

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

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

1993-01-01

43

[Genetic analysis of maize cytoplasmic male sterile mutants obtained by space flight].  

PubMed

Three maize male sterile mutants were obtained from the offsprings of two maize inbred lines 18-599 and 08-641, which were carried into space by the Shijian 8 Satellite. The stability of male sterile expression was observed in different locations, years, and seasons. In order to analyze the genetic characteristic of male sterility, testcross, backcross and reciprocal cross were made with these male sterile plants. The results showed that the male sterility character was stable in different locations, years, and seasons, and the sterility was inheritable. Because the maintainer lines and restorer lines for these sterile materials were found, and there was no male sterile plant separated among the reciprocal cross F2. Thus, we concluded that these mutants could be cytoplasmic male sterile. Combining the results of male fertility restoration test and PCR analysis, we could conclude that the three male sterile mutants were classified into the CMS-C type in maize. Owing to their difference in fertility restoration, these mutants may belong to different subgroups of CMS-C type. The discovery of the three male sterile mutants increased the genetic diversity of CMS-C type, improved the tolerance to Bipolaris maydis, and laid a foundation for extensive application of CMS-C in seeds production. PMID:21377975

Zhang, Cai-Bo; Yuan, Guo-Zhao; Wang, Jing; Pan, Guang-Tang; Rong, Ting-Zhao; Cao, Mo-Ju

2011-02-01

44

Mitochondrion role in molecular basis of cytoplasmic male sterility.  

PubMed

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. PMID:24732436

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

2014-11-01

45

[Genetic analysis about maize male sterile mutant obtained by space flight].  

PubMed

The seeds of maize single hybrid Chuandan No. 9 were carried into space in 1996 by satellite. After the seeds were planted in field in comparison with travel in space seeds which was not carried into space. Fortunately, male sterile plants were discovered in one of the ear rows. The stability of male sterile expression was observed in different years, different locations and different generations. In order to analysis the genetic characteristic of male sterility, test cross, sister cross, back cross, reciprocal cross and self-pollination were conducted with these male sterile plants. The results showed that the male sterility was stable in different years and different locations, it is inheritable from generation to generation. The sterility is controlled by a single nuclear recessive gene. The appearance of male sterile mutant is the conclusion of gene mutation which happened in nuclear by space flight. This mutant material always accompanies with lower plant height. PMID:14577372

Cao, Mo-Ju; Rong, Ting-Zhao; Pan, Guang-Tang

2003-09-01

46

Genetic basis of male sexual behavior  

Microsoft Academic Search

Male sexual behavior is increasingly the focus of genetic study in a variety of animals. Genetic analysis in the soil roundworm Caenorhabditis elegans and the fruit fly Drosophila melanogaster has lead to identification of genes and circuits that govern behaviors ranging from motivation and mate-searching to court- ship and copulation. Some worm and fly genes have counterparts with related functions

Scott W. Emmons; Jonathan Lipton

2003-01-01

47

Sterilization.  

PubMed

Male and female sterilization is a safe and effective form of permanent contraception. The number of patients accepting this method has rapidly increased over the last ten years and is likely to continue. In some countries the rate has plateaued out: in the USA it has been 31 per cent of all married women for the last eight years. Before sterilization it is important that adequate counselling is given to both partners and that the decision is not hurried. This is emphasized by the number of women and men requesting reversal of sterilization (thought to be between 0.1 and 10 per cent of all sterilizations). These requests for reversal usually come from couples who have remarried, tend to be younger, have fewer live children, have had more abortions, less schooling and are poor users of contraception. In these high-risk patients counselling and time to make the decision is essential. Other studies indicate that regret after puerperal sterilization may be commoner, but the risks of further pregnancies have to be weighed against sterilization regret. The methodology of male sterilization has changed little in the last ten years; it is simple and usually done under local anaesthesia. In contrast, female sterilization methods are constantly being refined, from laparotomy to laparoscopy and from extensive tubal destruction or excision to minimal tubal damage. The common methods now are mini-laparotomy and laparoscopy under local or general anaesthesia, with tubal occlusion by clips, rings or bipolar or thermal coagulation. There is no place now for unipolar diathermy, because of the higher complication rate, especially for major complications such as bowel burns. Recent multicentre studies comparing different methods give low rates for immediate morbidity and surgical complications (0.8 to 2.5 per cent of cases). Technical failure is rare but often due to a pre-existing condition, for example obesity or previous pelvic disease. Some failures are due, however, to difficulties with the instruments, especially at laparoscopy; here further developments and the use of teaching aids for those in training will help to reduce problems. Mortality from female sterilization is low, at 2 to 10 per 100 000 procedures; however, half is due in part to anaesthetic complications (hypoventilation), which can be avoided by intubation, and others are due to pre-existing medical conditions. Long-term follow-up has now shown that sterilization does not cause an increase in menstrual blood loss.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:6239731

Newton, J R

1984-12-01

48

Male sterility and enhanced radiation sensitivity in TLS–/– mice  

PubMed Central

TLS (also known as FUS) is an RNA-binding protein that contributes the N-terminal half of fusion oncoproteins implicated in the development of human liposarcomas and leukemias. Here we report that male mice homozygous for an induced mutation in TLS are sterile with a marked increase in the number of unpaired and mispaired chromosomal axes in pre-meiotic spermatocytes. Nuclear extracts from TLS–/– testes lack an activity capable of promoting pairing between homologous DNA sequences in vitro, and TLS–/– mice and embryonic fibroblasts exhibit increased sensitivity to ionizing irradiation. These results are consistent with a role for TLS in homologous DNA pairing and recombination. PMID:10654943

Kuroda, Masahiko; Sok, John; Webb, Lisa; Baechtold, Heidi; Urano, Fumihiko; Yin, Yin; Chung, Peter; de Rooij, Dirk G.; Akhmedov, Alexandre; Ashley, Terry; Ron, David

2000-01-01

49

All Male Strains and Chemical Stimulants: Two Ways to Boost Sterile Males in SIT Programs  

Technology Transfer Automated Retrieval System (TEKTRAN)

Genetic and chemical means have been developed to significantly improve the effectiveness of the sterile insect technique against tephritid fruit flies in recent years. Beginning with the development of genetic sexing techniques some 25 years ago, all-male strains of several species of fruit flies h...

50

Specific expression in reproductive tissues and fate of a mitochondrial sterility-associated protein in cytoplasmic male-sterile bean.  

PubMed Central

In common bean, cytoplasmic male sterility has been associated with a unique sequence found in the mitochondrial genome, designated pvs (for Phaseolus vulgaris sterility sequence). Within the pvs sequence, two open reading frames are encoded, ORF98 and ORF239. We have raised rabbit polyclonal antibodies against Pvs-ORF239 to evaluate the role of this putative male sterility-associated protein. Histological investigation of pollen development revealed that in the male-sterile bean line, callose deposition was abnormal and microspores remained as tetrads as previously reported. Pvs-ORF239 was found to be localized within the reproductive tissues of the male-sterile bean line, in contrast to all other cytoplasmic male sterility systems studied to date. This protein was associated with mitochondria, the callose layer, and developing primary cell walls during microsporogenesis. Expression of pvs-orf239 was not detected in fertile plants containing restorer gene Fr2. These observations, together with previous reports, suggest that nuclear restorer gene Fr2 interferes with expression of the pvs region post-transcriptionally. PMID:7734962

Abad, A R; Mehrtens, B J; Mackenzie, S A

1995-01-01

51

Possible mitochondrial involvement in mechanism of cytoplasmic male sterility in maize ( Zea mays L.)  

Microsoft Academic Search

The mechanism of cytoplasmic male sterility was investigated in maize by isolating mitochondria from seedlings and various anther stages and analyzing cytochrome oxidase and succinic dehydrogenase biochemically and electrophoretically. Sterile anthers exhibited a lack of biochemical activity and fewer isozymatic bands for cytochrome oxidase. No apparent differences were detected biochemically or electrophoretically between fertile and sterile anthers for succinate dehydrogenase.

C. V. Watson; J. Nath; Dave Nanda

1977-01-01

52

Sterilization and Training for Normal Sexual Development: Human Rights and Obligations.  

ERIC Educational Resources Information Center

This paper notes the lack of attention given to the sexuality of people with intellectual disabilities in both the literature and service delivery (in Australia). It discusses sterilization issues (such as authority to give consent and the "best interest" concept) and recommends approaches less intrusive on individual rights than sterilization.…

Ashman, Adrian F.

1990-01-01

53

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

USGS Publications Warehouse

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.

Hanson, L.H.

1990-01-01

54

Hybridization using cytoplasmic male sterility and herbicide tolerance from nuclear genes  

SciTech Connect

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.

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

1987-04-14

55

Early events in speciation: Polymorphism for hybrid male sterility in Drosophila  

E-print Network

Early events in speciation: Polymorphism for hybrid male sterility in Drosophila Laura K. Reed of hybrid male sterility in crosses between Drosophila mojavensis and its sister species, Drosophila variation in the Drosophila melanogaster species group. Mutations that rescue inviable hybrids have been

Markow, Therese

56

Testosterone and sexual signalling in male house sparrows ( Passer domesticus )  

Microsoft Academic Search

Female preference for mates with elaborated ornaments has often been explained on the basis that exaggerated secondary sexual traits might reflect individual quality and females might gather direct and indirect benefits in mating with such males. Sexual signals must however also entail costs to be reliable indicators of male quality. Androgens have been suggested as a physiological link between sexual

Guillermo Gonzalez; Gabriele Sorci; Linda C. Smith; Florentino de Lope

2001-01-01

57

Males' evolutionary responses to experimental removal of sexual selection  

E-print Network

Males' evolutionary responses to experimental removal of sexual selection Scott Pitnick1* , Gary T, CA 94720, USA We evaluated the in£uence of pre- and post-copulatory sexual selection upon male reproductive traits in a naturally promiscuous species, Drosophila melanogaster. Sexual selection was removed

Pitnick, Scott

58

Personality and attitudinal characteristics of sexually coercive college males  

Microsoft Academic Search

To identify the characteristics of male participants in coercive sexual activities, 190 college males completed a survey of their involvement in coercive sexual behavior and a battery of measures selected to reflect conceptually relevant dimensions of coercive sexuality, including the short form of the Attitudes Toward Women Scale and the scales from the California Psychological Inventory. Consistent with reports in

Karen Rapaport; Barry R. Burkhart

1984-01-01

59

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

SciTech Connect

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. (author) [Spanish] La colonia actualmente usada para controlar la mosca mexicana de la fruta, Anastrepha ludens (Loew), en Mexico tiene mas de 10 anos en cria masiva. Los insectos esteriles son liberados en una gran variedad de condiciones ambientales como parte de un control integrado para suprimir diversas poblaciones de esta plaga dentro de la Republica Mexicana. El objetivo de este documento esta dirigido a revisar el desempeno de las moscas esteriles frente a poblaciones silvestres procedentes de diferentes ambientes y para esto se realizaron comparaciones de compatibilidad y competitividad sexual de las moscas esteriles contra poblaciones silvestres de seis estados representativos de la Republica Mexicana: Nuevo Leon, Tamaulipas, Sinaloa, Nayarit, Michoacan y Chiapas. Los resultados obtenidos manifiestan diferencias en el horario de inicio de llamado y mayor actividad sexual del macho entre las moscas provenientes de cada estado. Sin embargo el indice de aislamiento (ISI) reflejo compatibilidad sexual entre la cepa de laboratorio y todas las poblaciones analizadas, indicando que los individuos esteriles pueden aparearse satisfactoriamente con las poblaciones silvestres de los seis estados. El indice de efectividad de apareamiento del macho (MRPI) reflejo de manera global que los machos esteriles son tan efectivos para copular como los silvestres. El indice de efectividad de apareamiento de la hembra (FRPI) reflejo que en la mayoria de los estados las hembras silvestres copularon en mayor proporcion que las hembras esteriles, excepto para las poblaciones de Tamaulipas y Chiapas. En general, la baja participacion de las hembras esteriles en el campo permitio al macho esteril ampliar su probabilidad de apareamiento con las hembras silvestres. En cuanto al indice de esterilidad relativa (RSI), observamos que la aceptacion de las hembras silvestres al macho esteril (25-55%) fue similar a la de los machos silvestres. Las hembras de la poblacion de Chiapas registro la menor aceptacion. Finalmente, los resultados obtenidos en la prueba de Fried, la cual determi

Orozco-Davila, D.; Hernandez, R.; Meza, S.; Dominguez, J. [Programa Moscamed Moscafrut-Desarrollo de Metodos, Central Poniente No. 14 altos-Esq. 2a Avenida Sur. CP 30700 Tapachula, Chiapas (Mexico)

2007-03-15

60

Genetic determination of male sterility in gynodioecious Silene nutans  

PubMed Central

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

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

2011-01-01

61

Genetic determination of male sterility in gynodioecious Silene nutans.  

PubMed

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

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

2011-05-01

62

Cytoplasmic male sterility in Mimulus hybrids has pleiotropic effects on corolla and pistil traits  

PubMed Central

The mechanisms underlying genetic associations have important consequences for evolutionary outcomes, but distinguishing linkage from pleiotropy is often difficult. Here, we use a fine mapping approach to determine the genetic basis of association between cytonuclear male sterility and other floral traits in Mimulus hybrids. Previous work has shown that male sterility in hybrids between Mimulus guttatus and Mimulus nasutus is due to interactions between a mitochondrial gene from M. guttatus and two tightly linked nuclear restorer alleles on Linkage Group 7, and that male sterility is associated with reduced corolla size. In the present study, we generated a set of nearly isogenic lines segregating for the restorer region and male sterility, but with unique flanking introgressions. Male-sterile flowers had significantly smaller corollas, longer styles and greater stigmatic exsertion than fertile flowers. Because these effects were significant regardless of the genotypic composition of introgressions flanking the restorer region, they suggest that these floral differences are a direct byproduct of the genetic incompatibility causing anther abortion. In addition, we found a non-significant but intriguing trend for male-sterile plants to produce more seeds per flower than fertile siblings after supplemental pollination. Such pleiotropic effects may underlie the corolla dimorphism frequently observed in gynodioecious taxa and may affect selection on cytoplasmic male sterility genes when they initially arise. PMID:21245895

Barr, C M; Fishman, L

2011-01-01

63

MALE STERILITY, PROTOGYNY, AND POLLEN-PISTIL INTERFERENCE IN PLANTAGO MARITIMA (PLANTAGINACEAE), AW IND -POLLINATED, SELF-INCOMPATIBLE PERENNIAL  

Microsoft Academic Search

Evolution and maintenance of male sterility in seed plants can be explained by the maternal inheritance of mitochondria, which encode the trait, and by adaptive functions that enhance female fecundity in male-sterile compared to hermaphrodite individuals. Protogyny and male sterility can independently decrease the negative effect of pollen-pistil interference in self- incompatible species. In Plantago maritima, which possesses both traits,

PATRIK DINNETZ

64

Cytoplasmic Male Sterility Contributes to Hybrid Incompatibility Between Subspecies of Arabidopsis lyrata  

PubMed Central

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

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

2013-01-01

65

Forensic Medical Aspects of Male-on-Male Rape and Sexual Assault in Greater Manchester  

Microsoft Academic Search

Male-on-male rapes and sexual assaults comprise fewer than 10% of such assaults reported to the police, and so many physicians seldom encounter them. This paper provides an overview of the nature of sexual assault encountered by males, ensuing injuries, and comparisons to male-on-female assault cases. The retrospective epidemiological study was on two cohorts seen at St. Mary's Sexual Assault Referral

I. A McLEAN; V. BALDING; C. WHITE

2004-01-01

66

Comparing male escorts' sexual behaviour with their last male client versus non-commercial male partner.  

PubMed

Apart from research suggesting that male escorts are less likely to have condomless anal sex (CAS) with their male clients compared with male non-clients, little is known about how male escorts' behaviour differs between their clients and non-clients. In spring 2013, 387 Internet-based male escorts completed an online survey that included identical questions about their sexual behaviour with their last male client and male non-client. Encounters with non-commercial partners were significantly more likely to involve a greater range of sexual behaviours, including giving oral sex to partner, kissing, anal receptive sex and sex without condoms. These findings suggest that escorts may display a greater sexual repertoire with non-commercial partners compared to their clients. Encounters with non-commercial partners were also rated as more satisfying than with clients. Condomless anal sex was less common with clients, suggesting that escorts and clients may take active roles in mitigating risks for HIV and STI transmission with each other. Although the modal response for CAS was to abstain, more than half of participants reported CAS during at least one of the two encounters assessed. Behavioural and/or biomedical HIV-prevention strategies would be appropriate for some male escorts to reduce HIV transmission risk. PMID:25277601

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

2015-02-01

67

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

PubMed

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. PMID:25118413

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

2014-07-01

68

Male victims of sexual assault: phenomenology, psychology, physiology.  

PubMed

Myths, stereotypes, and unfounded beliefs about male sexuality, in particular male homosexuality, are widespread in legal and medical communities, as well as among agencies providing services to sexual assault victims. These include perceptions that men in noninstitutionalized settings are rarely sexually assaulted, that male victims are responsible for their assaults, that male sexual assault victims are less traumatized by the experience than their female counterparts, and that ejaculation is an indicator of a positive erotic experience. As a result of the prevalence of such beliefs, there is an underreporting of sexual assaults by male victims; a lack of appropriate services for male victims; and, effectively, no legal redress for male sexual assault victims. By comparison, male sexual assault victims have fewer resources and greater stigma than do female sexual assault victims. Many male victims, either because of physiological effects of anal rape or direct stimulation by their assailants, have an erection, ejaculate, or both during the assault. This is incorrectly understood by assailant, victim, the justice system, and the medical community as signifying consent by the victim. Studies of male sexual physiology suggest that involuntary erections or ejaculations can occur in the context of nonconsensual, receptive anal sex. Erections and ejaculations are only partially under voluntary control and are known to occur during times of extreme duress in the absence of sexual pleasure. Particularly within the criminal justice system, this misconception, in addition to other unfounded beliefs, has made the courts unwilling to provide legal remedy to male victims of sexual assault, especially when the victim experienced an erection or an ejaculation during the assault. Attorneys and forensic psychiatrists must be better informed about the physiology of these phenomena to formulate evidence-based opinions. PMID:21653264

Bullock, Clayton M; Beckson, Mace

2011-01-01

69

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

PubMed

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. PMID:23786049

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

2013-04-01

70

Husband-Wife Communication, Wife's Employment, and the Decision for Male or Female Sterilization.  

ERIC Educational Resources Information Center

Examined relationships between perceptions of marital communication and the choice of male or female sterilization in 313 couples. The wife's perception of marital communication was negatively related to the tendency for the couple to choose female sterilization, conditional on female labor force participation. Communication questions are…

Bean, Frank D.; And Others

1983-01-01

71

Risk Factors for Male Sexual Aggression on College Campuses  

Microsoft Academic Search

Risk factors for college male sexual aggression that were both theoretically and empirically based were tested using multivariate regression analyses. These included substance abuse patterns, pornography consumption, negative gender-based attitudes, and child sexual abuse experiences. Regression analyses indicated that some gender attitudes, pornography use, and alcohol abuse were significant predictors of perpetration of sexual violence. Although a number of men

Joetta L. Carr; Karen M. VanDeusen

2004-01-01

72

A genetic study of male sexual orientation.  

PubMed

Homosexual male probands with monozygotic cotwins, dizygotic cotwins, or adoptive brothers were recruited using homophile publications. Sexual orientation of relatives was assessed either by asking relatives directly, or when this was impossible, asking the probands. Of the relatives whose sexual orientation could be rated, 52% (29/56) of monozygotic cotwins, 22% (12/54) of dizygotic cotwins, and 11% (6/57) of adoptive brothers were homosexual. Heritabilities were substantial under a wide range of assumptions about the population base rate of homosexuality and ascertainment bias. However, the rate of homosexuality among nontwin biological siblings, as reported by probands, 9.2% (13/142), was significantly lower than would be predicted by a simple genetic hypothesis and other published reports. A proband's self-reported history of childhood gender non-conformity did not predict homosexuality in relatives in any of the three subsamples. Thus, childhood gender nonconformity does not appear to be an indicator of genetic loading for homosexuality. Cotwins from concordant monozygotic pairs were very similar for childhood gender nonconformity. PMID:1845227

Bailey, J M; Pillard, R C

1991-12-01

73

Epidemiological characteristics of male sexual assault in a criminological database.  

PubMed

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

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

2012-02-01

74

Sexually dimorphic nuclei in the spinal cord control male sexual functions  

PubMed Central

Lower spinal cord injuries frequently cause sexual dysfunction in men, including erectile dysfunction and an ejaculation disorder. This indicates that the important neural centers for male sexual function are located within the lower spinal cord. It is interesting that the lumbar spinal segments contain several neural circuits, showing a clear sexually dimorphism that, in association with neural circuits of the thoracic and sacral spinal cord, are critical in expressing penile reflexes during sexual behavior. To date, many sex differences in the spinal cord have been discovered. Interestingly, most of these are male dominant. Substantial evidence of sexually dimorphic neural circuits in the spinal cord have been reported in many animal models, but major issues remain unknown. For example, it is not known how the different circuits cooperatively function during male sexual behavior. In this review, therefore, the anatomical and functional significance of the sexually dimorphic nuclei in the spinal cord corresponding to the expression of male sexual behavior is discussed. PMID:25071429

Sakamoto, Hirotaka

2014-01-01

75

Predictors of Sexual Aggression among Male Juvenile Offenders  

ERIC Educational Resources Information Center

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,…

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

2012-01-01

76

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

E-print Network

) showthatlargereggsexperiencehighersurvivorship,butfailtoidentify male-mediated effects or address between-pregnancy trade-offs25LETTERS Post-copulatory sexual selection and sexual conflict in the evolution of male pregnancy Kimberly A. Paczolt1 & Adam G. Jones1 Male pregnancy in seahorses, pipefishes and sea dragons (family

Sorenson, Michael

77

ORIGINAL PAPER Innate responses to male sexual harassment  

E-print Network

/ Published online: 31 July 2008 # Springer-Verlag 2008 Abstract Male mosquitofish are very persistent shoals. They also approach other males to promote male competition, and when males differ in size social preference in three groups of females that differed in experience of sexual harassment

Pilastro, Andrea

78

Sexual size dimorphism and male combat in snakes  

Microsoft Academic Search

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

Richard Shine

1978-01-01

79

Mitochondrial DNA variation within P-type cytoplasmic male sterility of Plantago lanceolata L  

Microsoft Academic Search

MtDNA restriction fragment polymorphisms were found between cytoplasmic male-sterility types P and R of Plantago lanceolata with the homologous probe pPl311 and maize mtDNA fragments derived from the regions of atp1, cox1 and cox2. No mtDNA differences were observed between male-sterile and restored plants with the same cytoplasmic type. The consistency of the polymorphisms was studied in 83 plants from

CAROLINA F M GROENENDIJK; JOHANNES M SANDBRINK; JAN VAN BREDERODE; JOS M M VAN DAMME

1997-01-01

80

[Cytological observation on pollen abortion of genetic male sterile mutant induced by space flight in maize].  

PubMed

In order to understand the cytological mechanism of pollen abortion of genetic male sterile mutant induced by space flight in maize, the sister cross population were used for sterility analysis and cytological observation. Intact anther observation, isolated cells observation and paraffin section were adopted in this research. The results showed that pollen abortion occured mostly in dyad stage of meiosis in genetic male sterile mutant. The dyad were degenerated with abnormal shape. In late anther developing stage, the tapetal cells were giant vacuolated and delayed degeneration. The pollen mother cells (PMC) began to dissolve and degenerate in a few anther before meiosis. PMID:18254342

Li, Shi Zhao; Cao, Mo Ju; Rong, Ting Zhao; Pan, Guang Tang; Tang, Qi Lin; Zhu, Ying Guo

2007-10-01

81

Interactions among Fertile Male, Female, and Sterile Male Sea Lampreys during Spawning in the Carp River, Lake Superior  

Microsoft Academic Search

Spawning interactions among fertile male, female, and sterilized male sea lampreys Petromyzon marinus were examined by placing externally attached radiotransmitters on 4% (52 animals) of the population of sea lampreys that was introduced above a barrier to their passage in the Carp River, which flows into Lake Superior, during 1996 and 1997. Movements and interactions on nests made by sea

J. R. M. Kelso; W. M. Gardner; R. B. McDonald

2001-01-01

82

Instability in mitochondrial membranes in Polima cytoplasmic male sterility of Brassica rapa ssp. chinensis.  

PubMed

Cytoplasmic male sterility (CMS) is an important factor to observe heterosis in Brassica rapa. Although several studies have documented the rearrangements of mitochondrial DNA and dysfunction in the mitochondria have been observed in most types of CMS, the basis of the molecular mechanisms involved in these processes and other effects on CMS remain unclear. In this study, suppression subtractive hybridization was performed in the flowers of an alloplasmic Polima CMS system from B. rapa ssp. chinensis to identify genes that are differentially expressed between fertile and sterile plants. A total of 443 clones were isolated (156 were upregulated in fertile buds, and 287 were upregulated in sterile ones). Real-time RT-PCR further demonstrated the credibility of SSH. Among these genes, many membrane protein genes (LTP12, PIP2A, and GRP14) were inhibited in the sterile male line. Mitochondrial membrane potential (MMP) assay was then performed. Results showed that the sterile MMP was unstable and failed to create a potential difference; thus, mitochondrial dysfunction occurred. Moreover, abnormal microtubules and photosynthetic pathways were found in sterile male cells. Unstable MMP, nutritional deficiency, and abnormal microtubules were the causes of Polima CMS in Brassica campestris. H2O2, MDA, and O(2-), accumulated as byproducts of energy metabolism disorder in sterile male cells. PMID:24652098

Li, Ying; Liu, Tongkun; Duan, Weike; Song, Xiaoming; Shi, Gongjun; Zhang, Jingyi; Deng, Xiaohui; Zhang, Shuning; Hou, Xilin

2014-06-01

83

[Locating maize male sterility gene induced by space flight using microsatellite markers].  

PubMed

Two F2 populations with different kinds of spike derived from maize male sterility materials RP(3)195 (A) x S37 (inbred line) ,which had been sib-bred for many generations,were used for sterility analysis and gene location. There were 138 and 247 plants in the two F2 populations respectively. Among the 326 pairs of microsatellite primers selected,56 were found polymorphic. Linkage analysis of F2 populations with the 56 pairs of primers showed that microsatellite markers bnlg197 and umc1012 were linked with the male sterility gene. The genetic distance between marker bnlgl97 and the male sterility gene in the two different F2 populations were 7 cM and 14.5 cM respectively. The genetic distance between marker umc1012 and the male sterility gene in the 138 plants was 28.5 cM. Thus the male sterility gene was located on chromosome 3L. PMID:16078745

Liu, Fu-Xia; Cao, Mo-Ju; Rong, Ting-Zhao; Pan, Guang-Tang

2005-07-01

84

Male brush-turkeys attempt sexual coercion in unusual circumstances.  

PubMed

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

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

2014-07-01

85

Psychologists' Attitudes Toward Adult Male Survivors of Sexual Abuse.  

ERIC Educational Resources Information Center

Examined 154 psychologists' (82 female, 72 male) reactions to vignettes describing the sexual abuse of a male victim. Results indicate that the psychologists' attitudes toward men, rather than the sex of the psychologists, predicted blaming attitudes. For example, those holding more traditional attitudes toward men tended to blame male survivors…

Richey-Suttles, Stephen; Remer, Rory

1997-01-01

86

Perceptions of Child Support and Sexual Activity of Adolescent Males  

ERIC Educational Resources Information Center

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

Huang, Chien-Chung; Han, Wen-Jui

2004-01-01

87

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

PubMed Central

Known in over 150 species, cytoplasmic male sterility is encoded by aberrant mitochondrial genes that prevent pollen development. The RNA- or protein-level expression of most of the mitochondrial genes encoding cytoplasmic male sterility is altered in the presence of one or more nuclear genes called restorers of fertility that suppress the male-sterile phenotype. Cytoplasmic male sterility/restorer systems have been proven to be an invaluable tool in the production of hybrid seeds. Despite their importance for both the production of major crops such as rice and sunflower and the study of organelle/nuclear interactions in plants, none of the nuclear fertility-restorer genes that reduce the expression of aberrant mitochondrial proteins have previously been cloned. Here we report the isolation of a gene directly involved in the control of the expression of a cytoplasmic male sterility-encoding gene. The Petunia restorer of fertility gene product is a mitochondrially targeted protein that is almost entirely composed of 14 repeats of the 35-aa pentatricopeptide repeat motif. In a nonrestoring genotype we identified a homologous gene that exhibits a deletion in the promoter region and is expressed in roots but not in floral buds. PMID:12136123

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

2002-01-01

88

SEXUAL STERILIZATION OF THE DAGGERBLADE GRASS SHRIMP PALAEMONETES PUGIO (DECAPODA, PALAEMONIDAE) BY THE BOPYRID ISOPOD PROBOPYRUS PANDALICOLA (ISOPODA, BOPYRIDAE).  

PubMed

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

Sherman, Michele B; Curran, Mary Carla

2014-10-29

89

Measuring Love: Sexual Minority Male Youths’ Ideal Romantic Characteristics  

Microsoft Academic Search

Research examining how sexual minorities characterize love within same-sex relationships is scarce. In this study, the authors 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, the authors examined the psychometric properties of the Triadic Love Scale (TLS) and

JosÉ A. Bauermeister; Michelle M. Johns; Emily Pingel; Anna Eisenberg; Matt Leslie Santana; Marc Zimmerman

2011-01-01

90

Hybrid seed production and the challenge of propagating male-sterile plants.  

PubMed

The introduction of hybrid crop varieties has enabled spectacular increases in productivity owing to hybrid vigor and increased uniformity. To produce hybrid seeds, a pollination control system is required to prevent unwanted self-pollination. In crop species with hermaphrodite flowers, this can be a major challenge. Over the past decade, new pollination control systems have been developed with the aid of genetic engineering, mainly based on the generation of nuclear-encoded male sterility. The successful application of these systems for large-scale hybrid seed production depends on whether the male-sterile female parent line can be multiplied efficiently and economically. In spite of its relevance, the propagation of the male-sterile line has often been overlooked in the development of pollination control systems. PMID:11992824

Perez-Prat, Eva; van Lookeren Campagne, Michiel M

2002-05-01

91

Further Aspects of Male-on-Male Rape and Sexual Assault in Greater Manchester  

Microsoft Academic Search

The purpose of this paper is to describe pertinent non-medical circumstances around male-on-male sexual assault, and supplements the earlier article in this journal regarding forensic medical aspects of this population. As services (medical, policing and judicial) see more males they will need to adapt themselves to their needs as well as those of their female clients. St. Mary's Sexual Assault

I. A McLean; V. Balding; C. White

2005-01-01

92

Sexual isolation of male moths explained by a single pheromone response QTL containing four  

E-print Network

Sexual isolation of male moths explained by a single pheromone response QTL containing four, 2009) Long distance sexual communication in moths has fascinated biologistsbecauseofthe complex the genetic architecture of sexual isolation in males of two congeneric moths, Heliothis subflexa

93

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...

94

Sexual behavior patterns of customers of male street prostitutes.  

PubMed

Information about male customers of male prostitutes, including sociodemographic and life-style characteristics, sexual and drug use behaviors, and knowledge about HIV infection were collected from a convenience sample of 211 male street prostitutes and a convenience sample of 15 male customers as part of a feasibility study. Data from these two groups indicate that despite knowledge of HIV infection and its transmission, customers engage in high-risk sexual and drug use behaviors with prostitutes. Because there is a high HIV infection rate within the male prostitute sample (175/1000) and because these customers for the most part describe themselves as bisexual or heterosexual, it is likely that male customers of male prostitutes serve as a vector of transmission of HIV infection to their other partners including the heterosexual population. PMID:1497473

Morse, E V; Simon, P M; Balson, P M; Osofsky, H J

1992-08-01

95

Examining the Development and Sexual Behavior of Adolescent Males  

PubMed Central

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

Ott, Mary A.

2010-01-01

96

Male sterility in triploid dandelions: asexual females vs asexual hermaphrodites  

Microsoft Academic Search

Male reproductive output, pollen in plants and sperm in animals has been shown to constitute a substantial cost for many organisms. In parthenogenetic hermaphrodites, selection is therefore expected to reduce the allocation of resources to male reproductive output. However, sustained production of pollen or sperm has been observed in numerous asexual hermaphrodites. We studied the widespread production of pollen by

P G Meirmans; P H Van Tienderen

2006-01-01

97

Measuring Love: Sexual Minority Male Youths’ Ideal Romantic Characteristics  

PubMed Central

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. PMID:21709758

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

2011-01-01

98

JAMA Patient Page: Male Sexual Dysfunction  

MedlinePLUS

... share with patients. Any other print or online reproduction is subject to AMA approval. To purchase bulk reprints, call 718/946-7424. • Low libido (sexual interest) • Erectile dysfunction (ED, difficulty achieving or maintaining ...

99

Premarital Sexual Behavior among male college students of Kathmandu, Nepal  

PubMed Central

Background In Nepal, as in other Asian countries, the issue of sexuality still remains a taboo. Despite this fact, an increasing number of sexual activities is being reported by Nepalese students. This trend warrants serious and timely attention. Due to the sensitivity of the topic of premarital sexuality, youth receive inadequate education, guidance and services on reproductive health. The main objectives of this paper are to explore the sexual behavior especially focusing on prevalence of premarital sex among college men and to investigate the factors surrounding premarital sexual behavior. Methods A cross-sectional survey of college students was conducted in April-May 2006. A self-administered questionnaire was completed by 573 male students. Association between premarital sex and the explanatory variables was assessed in bivariate analysis using Chi-square tests. The associations were further explored using multivariate logistic analysis. Results Despite the religious and cultural restrictions, about two-fifths of survey respondents (39%) reported that they have had premarital sex. The study has also shown that substantial proportions of students indulge in sexual activities as well as risky sexual behavior. Sex with commercial sex workers, multiple sex partners, and inconsistence use of condom with non-regular partner was common among the students. Less than two in five male students (57%) had used condom at the first sexual intercourse. The prevalence of premarital sex varied on different settings. Older students aged 20 and above were more likely to have premarital sex compared with younger students aged 15–19. Men who had liberal attitude towards male virginity at marriage were almost two times more likely to have engaged in premarital sex compared to their counterparts who have conservative attitude towards male virginity at marriage. Moreover, those students who believe in Hindu religion were more than two times (OR = 2.5) more likely to have premarital sex compared with those who follow other religions. Furthermore, those men who have close unmarried friends who have experienced premarital sexual intercourse were eight times (OR = 8.4) more likely to be sexually active compared to those who did not have such sexually active friends. Conclusion Prevalence of premarital sexual intercourse and risky sexual behavior are not uncommon in Nepal. Young people are exposed to health hazards due to their sexual behavior; hence sex education should be provided. School or college based sexuality education could benefit even out-of-school youths, because their partners often are students. PMID:19604383

Adhikari, Ramesh; Tamang, Jyotsna

2009-01-01

100

Genetic effects on male sexual coercion.  

PubMed

The genetic and environmental influences on sexual coercion, and to what extent its associations with alcohol use and psychopathy depend on shared genetic and environmental effects, were explored in a Finnish population-based sample of 938 men, aged 33-43 years, using the classical twin study design. All three phenotypes were associated positively and affected by genes (sexual coercion 28%, alcohol use 60%, psychopathy 54%), with 46% of the correlation between sexual coercion and psychopathy, 89% of the correlation between alcohol use and psychopathy and 100% of the correlation between sexual coercion and alcohol use being explained by shared genetic effects. Further, the results showed that a proportion of the variance in sexual coercion was derived from a highly genetic source that was common with alcohol use and psychopathy. This latent factor was hypothesized to reflect a general tendency for antisocial behavior that is pervasive across different situations. Relevant theories on sexual coercion were discussed in light of the results. PMID:17828754

Johansson, Ada; Santtila, Pekka; Harlaar, Nicole; von der Pahlen, Bettina; Witting, Katarina; Algars, Monica; Alanko, Katarina; Jern, Patrick; Varjonen, Markus; Sandnabba, N Kenneth

2008-01-01

101

Sexual identity: Conflict and confusion in a male adolescent  

Microsoft Academic Search

This paper presents a conceptual formulation, derived from developmental object relations theory and ego psychology, of the passage in male adolescence that culminates with the achievement of a masculine heterosexual identity. Themes of psychosexuality, male gender attributes, masculinity and object preference, and sexual orientation are discussed with reference to the adolescent stage. Finally, the critical tasks, core conflicts, and internalizations

Randolph L. Lucente

1996-01-01

102

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

PubMed

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

Paczolt, Kimberly A; Jones, Adam G

2010-03-18

103

Efficient transformation of Kalanchoe blossfeldiana and production of male-sterile plants by engineered anther ablation.  

PubMed

Engineered male sterility in ornamental plants has many applications such as facilitate hybrid seed production, eliminate pollen allergens, reduce the need for deadheading to extend the flowering period, redirect resources from seeds to vegetative growth, increase flower longevity and prevent gene flow between genetically modified and related native plants. We have developed a reliable and efficient Agrobacterium-mediated protocol for the genetic transformation of different Kalanchoe blossfeldiana commercial cultivars. Transformation efficiency for cv. 'Hillary' was 55.3% whereas that of cv. 'Tenorio' reached 75.8%. Selection was carried out with the nptII gene and increasing the kanamycin concentration from 25 to 100 mg l(-1) allowed to reduced escapes from 50 to 60% to virtually 0%. This method was used to produce male-sterile plants through engineered anther ablation. In our approach, we tested a male sterility chimaeric gene construct (PsEND1::barnase) to evaluate its effectiveness and effect on phenotype. No significant differences were found in the growth patterns between the transgenic lines and the wild-type plants. No viable pollen grains were observed in the ablated anthers of any of the lines carrying the PsEND1::barnase construct, indicating that the male sterility was complete. In addition, seed set was completely abolished in all the transgenic plants obtained. Our engineered male-sterile approach could be used, alone or in combination with a female-sterility system, to reduce the invasive potential of new ornamentals, which has become an important environmental problem in many countries. PMID:19921199

García-Sogo, Begoña; Pineda, Benito; Castelblanque, Lourdes; Antón, Teresa; Medina, Mónica; Roque, Edelín; Torresi, Claudia; Beltrán, José Pío; Moreno, Vicente; Cañas, Luis Antonio

2010-01-01

104

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

PubMed

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. PMID:23749450

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

2013-08-01

105

[Subthalamic lesions eliminate sexual behavior in the male rat].  

PubMed

Electrical stimulation of parts of the subthalamus and mesencephalon produces coordinated stepping movements, and for this reason these areas are sometimes referred to as the subthalamic and mesencephalic "locomotor" regions. In this study we contrast the sexual behavioral effect of electrolytic destruction of these two regions in the male rat. Lesions of the mesencephalic locomotor region had no significant effect on male sexual behavior. In contrast, subthalamic lesions centered on the caudal zona incerta just dorsal to the subthalamic nucleus eliminated sexual behavior in 6 of 15 males. The sexual behavior of the remaining males was affected to a lesser degree, for the most part in accord with the extent of destruction to this "critical zone." Subthalamic lesions produced no obvious impairment in locomotion, posture, limb use, muscle tone or sensorimotor orientation. Even so, the fact that electrical stimulation of the subthalamus elicits coordinated stepping suggests that the region is linked with systems directly concerned with movement and locomotion. These links could be particularly important in the process by which sexual motivation is translated into sexual behavior. PMID:3183979

Maillard, C A; Edwards, D A

1988-01-01

106

Disruption of Arabidopsis thaliana MYB26 results in male sterility due to non-dehiscent anthers.  

PubMed

A male sterile mutant with a defect in anther dehiscence was identified in an Arabidopsis thaliana population mutagenized with the Zea mays transposon En-1/Spm. Mutants produce viable pollen that can fertilize when released mechanically from the anthers. Mutant stamens are of normal size and shape, but lack cell wall fortifications in the endothecial cell layer of the anther, which are required for the dehiscence process. The mutant phenotype was shown to be caused by a transposon insertion in AtMYB26, disrupting the putative DNA-binding domain of this R2R3-type MYB transcription factor. RT-PCR revealed that expression of AtMYB26 is restricted to inflorescences. Sterility was shown to be stable under several environmental conditions. The high stability of the sterile phenotype, together with the fact that pollen is functional, makes AtMYB26 and its orthologs a valuable tool for manipulating male fertility in higher plants. PMID:12753590

Steiner-Lange, Sabine; Unte, Ulrike S; Eckstein, Luca; Yang, Caiyun; Wilson, Zoe A; Schmelzer, Elmon; Dekker, Koen; Saedler, Heinz

2003-05-01

107

Male-on-male sexual assaults: an analysis of crime scene actions.  

PubMed

While the concept of male victimization is not a new phenomenon, the sexual assault of a male is a relatively new notion, emerging over the last 30 years in social research literature. Studies of female rape, pedophilia, and juvenile sex offenders have suggested that different styles of offending are reflected in the different types of behaviors committed by offenders at the crime scene. These studies suggest that there are three distinct themes of behavior: Control, Hostility, and Involvement. Using the crime scene actions of 305 male-on-male sexual assault from a U.K. national police database, multidimensional analysis was carried out. The proposed framework was found to be a useful way of classifying male-on-male sexual assaulters with 74% displaying a dominant theme. These resulted in 42% classified as displaying hostility, 23% as control, and 9% as involvement. Implications and suggestions for future research are discussed. PMID:24255070

Almond, Louise; McManus, Michelle A; Ward, Lydia

2014-05-01

108

Volunteer bias in human sexuality research: Evidence for both sexuality and personality differences in males  

Microsoft Academic Search

The extent to which personality, social behavior, and sexuality differed in undergraduate males under two different types\\u000a of recruitment, volunteer and nonvolunteer, was investigated. Nonvolunteers (N=160) were ostensibly recruited for a study on personality, and volunteers (N=204) were overtly recruited for a study on human sexuality. Both samples completed the same personality, social behavior,\\u000a and sexuality questionnaires. Volunteers were found

Anthony F. Bogaert

1996-01-01

109

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

Microsoft Academic Search

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

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

1983-01-01

110

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

Microsoft Academic Search

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

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

111

Independent segregation of the plastid genome and cytoplasmic male sterility in Petunia somatic hybrids  

Microsoft Academic Search

The chloroplast genomes of three sets of Petunia somatic hybrids were analyzed to examine the relationship between chloroplast DNA (cpDNA) composition and cytoplasmic male sterility (CMS). Chloroplast genomes of somatic hybrid plants were identified either by restriction and electrophoresis of purified cpDNAs or by hybridization of total DNA digests with cloned cpDNA probes that distinguish the parental genomes.

Ellen M. Clark; Shamay Izhar; Maureen R. Hanson

1985-01-01

112

ORIENTAL FRUIT FLY: MALES-ONLY STERILE FLY RELEASES IN HAWAII  

Technology Transfer Automated Retrieval System (TEKTRAN)

Beginning in late August, 2004, we began a program to release sterile male oriental fruit flies, Bactrocera dorsalis, in a citrus orchard in central Oahu, Hawaii. This program follows the encouraging results obtained with the melon fly genetic sexing strain on the islands of Hawaii, Maui, and Oahu. ...

113

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

E-print Network

of each anomaly, we would like to consider in more detail three groups : males with Klinefelter's syndrome constitution. 1. Klinefelter's syndrome. - The role of certain gonosomal anomalies in relation to sterility in Klinefelter's syndrome where the atrophic and hyalinized seminiferous tubules contain practically only Sertoli

Paris-Sud XI, Université de

114

A Quantitative Genetic Analysis of Nuclear-Cytoplasmic Male Sterility in Structured Populations of Silene vulgaris  

Microsoft Academic Search

Gynodioecy, the coexistence of functionally female and hermaphroditic morphs within plant popula- tions, often has a complicated genetic basis involving several cytoplasmic male-sterility factors and nuclear restorers. This complexity has made it difficult to study the genetics and evolution of gynodioecy in natural populations. We use a quantitative genetic analysis of crosses within and among populations of Silene vulgaris to

Douglas R. Taylor; Matthew S. Olson; David E. McCauley

115

All male strains and chemical stimulants: Two ways to boost sterile mailes in SIT programs  

Technology Transfer Automated Retrieval System (TEKTRAN)

Technical abstract: Genetic and chemical means have been developed to significantly improve the effectiveness of the sterile insect technique against tephritid fruit flies in recent years. Beginning with the development of genetic sexing techniques some 25 years ago, all-male strains of several spe...

116

Sexual Dysfunction and Pelvic Pain in Men: A Male Sexual Pain Disorder?  

Microsoft Academic Search

Male pelvic pain, often referred to as chronic prostatitis or chronic pelvic pain syndrome (CP\\/CPPS), is a common yet poorly understood problem, associated with significant sexual dysfunction. A critical review of the literature is presented, with specific attention to co-morbid sexual dysfunction. Recommendations for future multidisciplinary research and clinical work are also made.

Seth N. P. Davis; Yitzchak M. Binik; Serge Carrier

2009-01-01

117

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

PubMed

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

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

2014-03-11

118

Cytological study of a male-sterile Cryptomeria japonica that does not release microspores from tetrads  

Microsoft Academic Search

To determine the mechanism of male-sterility Cryptomeria japonica tree Shindai3, the process of microspore development was observed under light and fluorescence microscopy. Microspore development\\u000a in the Shindai3 was normal until the tetrad stage, but separation of the microspores from the tetrads was not observed even\\u000a after callose had been degraded. In contrast to the microspore stage in a male-fertile tree,

Hiroko Ueuma; Eri Yoshii; Yoshihiro Hosoo; Hideaki Taira

2009-01-01

119

Genic markers for wild abortive (WA) cytoplasm based male sterility and its fertility restoration in rice  

Microsoft Academic Search

Commercial exploitation of heterosis is essential for enhancing productivity of rice. The use of cytoplasmic male sterility\\u000a (CMS) and fertility restoration system greatly facilitates large scale production of hybrid seed. The wild abortive (WA) cytoplasm\\u000a is most widely used for hybrid seed production in rice. The present study was undertaken to develop molecular markers for\\u000a both WA cytoplasm based male

Umakanta Ngangkham; Swarup K. Parida; Sandip De; K. Anand Raj Kumar; Ashok K. Singh; Nagendra K. Singh; Trilochan Mohapatra

2010-01-01

120

Masculinity and the male role in sexual health.  

PubMed

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. PMID:12291933

Shephard, B

1996-01-01

121

How the Male Body Works Sexually  

MedlinePLUS

... urethra and out of the tip of the penis. The drawing below shows the male sex organs. The role of testosterone Testosterone is ... a man’s body, controls ejaculation of semen. How male orgasm ... (the tube running through the penis), so that it’s ready to be pushed out ( ...

122

A male-sterile insertion in the mouse  

Microsoft Academic Search

Is(7;l)40H was found in the daughter of a male mouse given spermatozoal X-irradiation. It is a non-inverted insertion of about half of chromosome 7 into chromosome 1, generating a long somatic marker chromosome. Breakpoints are in bands IB, 7B1, and 7F1; linkage tests show that these breakpoints are about midway between fz and In on the 1, and 0.2 units

A. G. Searle; C. V. Beechey; P. de Boer; D. G. de Rooij; E. P. Evans; M. Kirk

1983-01-01

123

A thermogenic secondary sexual character in male sea lamprey  

PubMed Central

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

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

124

Sexual activities, desire, and satisfaction in males pre- and post-spinal cord injury  

Microsoft Academic Search

Thirty-eight spinal cord injured (SCI) males (median age = 26) completed an 80-item multiple choice questionnaire (median 37 months postinjury) which assessed sexual functioning pre- and post-spinal cord injury in four areas: (i) sexual activities and preferences, (ii) sexual abilities, (iii) sexual desire, arousal, and satisfaction, and, (iv) sexual adjustment. Frequency of sexual activity decreased following SCI with a reduction

Craig J. Alexander; Marca L. Sipski; Thomas W. Findley

1993-01-01

125

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

SciTech Connect

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.

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

1987-04-14

126

Sexual Experience Enhances Drosophila melanogaster Male Mating Behavior and Success  

PubMed Central

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

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

2014-01-01

127

Male-male sexual behavior in the parasitic wasp Psyttalia concolor.  

PubMed

The role of male-male courtship in parasitic Hymenoptera is poorly known. A laboratory study was conducted to assess if Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae) male courtship can be affected by a previous experience in courting young conspecifics of both sexes. Two experiments were performed to evaluate the effect of experience in courting young wasps on both male courtship and male-male competition behavior. Results showed that a courting experience on both sexes can modify some sexual traits in a P. concolor male, without affecting its success in mating. When approaching virgin females, a P. concolor male that had a previous courtship experience with young wasps of either sex showed shorter latency times, more wing fanning, and longer courtship durations with respect to the control male. The hypothesis that a previous courting experience may allow a P. concolor male to refine its courtship behavior and to enhance courtship intensity in subsequent encounters with females was discussed. PMID:23895402

Benelli, Giovanni; Canale, Angelo

2013-01-01

128

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

Microsoft Academic Search

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

Dagmar Wilhelm; Peter Koopman

2006-01-01

129

Characteristic Male Urine Microbiomes Associate with Asymptomatic Sexually Transmitted Infection  

Microsoft Academic Search

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

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

2010-01-01

130

Sexual HIV risk among gay and bisexual male methamphetamine abusers  

Microsoft Academic Search

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

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

1996-01-01

131

Pelvic floor and sexual male dysfunction.  

PubMed

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

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

2013-03-01

132

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

PubMed

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

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

2014-01-01

133

Genetics of hybrid male sterility among strains and species in the Drosophila pseudoobscura species group  

PubMed Central

Taxa in the early stages of speciation may bear intraspecific allelic variation at loci conferring barrier traits in hybrids such as hybrid sterility. Additionally, hybridization may spread alleles that confer barrier traits to other taxa. Historically, few studies examine within- and between-species variation at loci conferring reproductive isolation. Here, we test for allelic variation within Drosophila persimilis and within the Bogota subspecies of D. pseudoobscura at regions previously shown to contribute to hybrid male sterility. We also test whether D. persimilis and the USA subspecies of D. pseudoobscura share an allele conferring hybrid sterility in a D. pseudoobscura bogotana genetic background. All loci conferred similar hybrid sterility effects across all strains studied, though we detected some statistically significant quantitative effect variation among D. persimilis alleles of some hybrid incompatibility QTLs. We also detected allelism between D. persimilis and D. pseudoobscura USA at a 2nd chromosome hybrid sterility QTL. We hypothesize that either the QTL is ancestral in D. persimilis and D. pseudoobscura USA and lost in D. pseudoobscura bogotana, or gene flow transferred the QTL from D. persimilis to D. pseudoobscura USA. We discuss our findings in the context of population features that may contribute to variation in hybrid incompatibilities. PMID:21729052

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

2011-01-01

134

Characteristics and allowed behaviors of gay male couples’ sexual agreements  

PubMed Central

Research has shown that gay male couples’ sexual agreements may affect their risk for HIV. Few U.S. studies have collected dyadic data nationally from gay male couples to assess what sexual behaviors they allow to occur by agreement type and the sequence of when certain behaviors occur within their relationships. In our cross-sectional study, dyadic data from a convenience sample of 361 male couples were collected electronically throughout the U.S. by using paid Facebook ads. Findings from our study revealed that couples discussed their HIV status before having UAI, but established their agreement some time after having UAI. About half of the couples (N = 207) concurred about having an agreement. Among these couples, 58% concurred about explicitly discussing their agreement, 84% concurred about having the same type of agreement, and 54% had both men adhering to it. A variety of sexual behaviors were endorsed and varied by agreement type. Concordance about aspects of couples’ agreements varied, suggesting the need to engage couples to be more explicit and detailed when establishing and communicating about their agreements. The allowed behaviors and primary reasons for establishing and breaking sexual agreements further highlight the need to bolster HIV prevention for gay male couples. PMID:23514544

Mitchell, Jason W.

2015-01-01

135

Symmetry, sexual dimorphism in facial proportions and male facial attractiveness  

E-print Network

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

Little, Tony

136

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

ERIC Educational Resources Information Center

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.…

Calhoun, Thomas; Pickerill, Brian

1988-01-01

137

Neonatal Endocrinology of Abnormal Male Sexual Differentiation: Molecular Aspects  

Microsoft Academic Search

Normal male sexual differentiation is a complex mechanism, depending on genetic and hormonal control. The bipotent gonad arises at the genital ridge under the control of autosomal genes which are also involved in the formation of other organs. Progression towards testicular differentiation is mediated through both autosomal and gonosomal genes, leading to alignment of Sertoli cells and Leydig cells. Within

Olaf Hiort

2000-01-01

138

Volunteer bias in a study of male alcoholics' sexual behavior  

Microsoft Academic Search

Studies on sexual behavior frequently require that subject volunteers engage in intrusive\\/sensitive assessment procedures. While earlier investigators have found that these demands may result in volunteer bias (volunteers differing from nonvolunteers), these studies were limited to nonclinical samples. The present study involved 182 males admitted to an inpatient alcoholism rehabilitation program. Those patients who volunteered to participate in an intrusive

Ted D. Nirenberg; John P. Wincze; Sudhir Bansal; Michael R. Liepman; Mindy Engle-Friedman; Ann Begin

1991-01-01

139

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

PubMed

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. PMID:15803965

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

2004-01-01

140

Sexual reproduction in Daphnia pulex (Crustacea: Cladocera): observations on male mating behaviour  

E-print Network

Sexual reproduction in Daphnia pulex (Crustacea: Cladocera): observations on male mating behaviour conditions. Keywords: clone, Daphnia, inbreeding, mating behaviour, sexual reproduction Introduction with the dif®culty of locating and identifying poten- tial mates during sexual reproduction. Gerritsen (1980

Innes, David J.

141

[The discovery of a specific DNA fragment associated with maize cytoplasmic male sterility and its differential display].  

PubMed

Three pairs of PCR primers were designed according to the mitochondrial DNA sequence. PCR amplification was applied to 3 sets of isonuclear alloplasm materials and 3 sets of isoplasm allonuclear materials. Multiplex PCR and general PCR protocol were adopted with total genomic DNA. As for the primers having detected polymorphsim between male sterility and its maintainers, differential display was conducted with mRNA from different development stage of microspore. The results showed as follows: with total genomic DNA template, primer P1-P2 has amplified a specific fragment only in all the male sterile materials, primer P5-P6 has amplified a specific fragment only in maintainer Huangzaosi, primer P3-P4 has no amplification in all the experiment materials. So primer P1-P2 can be used to distinguish male sterile cytoplasm and normal cytoplasm. RT-PCR was conducted with primer P1-P2 in inbred line huangzaosi and 48-2 with male sterile cytoplasm and normal cytoplasm, mRNA was separately isolated from tetrad stage, uninucleate stage and binucleate stage of microspore development, cDNA was obtained with random hexanucleotide primers. With the cDNA template, specific amplified fragments were also detected by primer P1-P2 in the male sterile materials at different development stage of microspore, but there was no amplification by primer P1-P2 in the 2 maintainer lines. This result indicated that primer P1-P2 can be transcripted at 3 development stages of microspore in all male sterile materials, and same transcript was produced by primer P1-P2 among all male sterile materials include 3 sets of isonuclear alloplasm and 3 sets of isoplasm allonuclear. It was suggested from this experiment that the specific DNA sequence detected by primer P1-P2 in all male sterile material total genomic DNA might be related to the cytoplasmic male sterile character. PMID:16257903

Cao, Mo-Ju; Rong, Ting-Zhao; Zhu, Ying-Guo

2005-09-01

142

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

PubMed

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

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

2014-12-01

143

Psychometrics and Comparison of the Compulsive Sexual Behavior Inventory and the Sexual Compulsivity Scale in a Male College Student Sample  

Microsoft Academic Search

The current study examined and compared the psychometric properties of the Sexual Compulsivity Scale and the Compulsive Sexual Behavior Inventory in male college students. Participants included 334 male undergraduate students enrolled in Introductory Psychology courses. Zero-order correlation analyses were conducted and statistically compared to identify sexual behaviors and constructs significantly and differentially related to scores on the CSBI and SCS.

Tayla T. C. Lee; Kristin A. Ritchey; Johnathan D. Forbey; George A. Gaither

2009-01-01

144

Xenotransplantation exposes the etiology of azoospermia factor (AZF) induced male sterility.  

PubMed

Ramathal et al. have employed an elegant xenotransplantation technique to study the fate of human induced pluripotent stem cells (hiPSCs) from fertile males and from males carrying Y chromosome deletions of the azoospermia factor (AZF) region. When placed in a mouse testis niche, hiPSCs from fertile males differentiate into germ cell-like cells (GCLCs). Highlighting the crucial role of cell autonomous factors in male sterility, hiPSCs derived from azoospermic males prove to be less successful under similar circumstances. Their studies argue that the agametic "Sertoli cell only" phenotype of two of the AZF deletions likely arises from a defect in the maintenance of germline stem cells (GSCs) rather than from a defect in their specification. These observations underscore the importance of the dialogue between the somatic niche and its inhabitant stem cells, and open up interesting questions concerning the functioning of the somatic niche and how it communicates to the GSCs. PMID:25524208

Barr, Justinn; Gordon, Daniel; Schedl, Paul; Deshpande, Girish

2015-03-01

145

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

SciTech Connect

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

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

2007-03-15

146

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

PubMed

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

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

2014-02-01

147

[Molecular-genetic analysis of maize mitochondrion regions associated with cytoplasmic male sterility].  

PubMed

Molecular-genetic polymorphism of 86 world and Ukrainian breeding maize lines with S-, C- and T-types of cytoplasmic male sterility (CMS) and with normal wild type mitochondrion has been researched via mitochondrion regions PCR-analysis. Molecular marker system allowed to detect and identify definite type of CMS within maize lines, as well as to differentiate lines with definite CMS type either from lines with another CMS type or from normal wild type cytoplasm lines. PMID:21774398

Slishchuk, H I; Kozhukhova, N E; Syvolap, Iu M

2011-01-01

148

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

PubMed Central

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

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

2007-01-01

149

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

E-print Network

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

Paris-Sud XI, Université de

150

Patterns of male sterility within and among populations of the distylous shrub Erythroxylum havanense (erythroxylaceae)  

Microsoft Academic Search

Distyly, a reproductive system characterized by the presence of long-styled (thrum). and short-styled (pin) individuals within a population, has been repeatedly used as a model for the study of the evolution of the reproductive systems in plants. Erythroxylum havanense is a distylous species in which most thrum plants fail to develop a fertile androecium, thus behaving as male-sterile or partially

Eduardo Cuevas; Francisco Molina-Freaner; Luis E. Eguiarte; César A. Domínguez

2005-01-01

151

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

Microsoft Academic Search

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

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

2009-01-01

152

Differential Proteomic Analysis of Anthers between Cytoplasmic Male Sterile and Maintainer Lines in Capsicum annuum L  

PubMed Central

Cytoplasmic male sterility (CMS), widely used in the production of hybrid seeds, is a maternally inherited trait resulting in a failure to produce functional pollen. In order to identify some specific proteins associated with CMS in pepper, two-dimensional gel electrophoresis (2-DE) was applied to proteomic analysis of anthers/buds between a CMS line (designated NA3) and its maintainer (designated NB3) in Capsicum annuum L. Thirty-three spots showed more than 1.5-fold in either CMS or its maintainer. Based on mass spectrometry, 27 spots representing 23 distinct proteins in these 33 spots were identified. Proteins down-regulated in CMS anthers/buds includes ATP synthase D chain, formate dehydrogenase, alpha-mannosidas, RuBisCO large subunit-binding protein subunit beta, chloroplast manganese stabilizing protein-II, glutathione S-transferase, adenosine kinase isoform 1T-like protein, putative DNA repair protein RAD23-4, putative caffeoyl-CoA 3-O-methyltransferase, glutamine synthetase (GS), annexin Cap32, glutelin, allene oxide cyclase, etc. In CMS anthers/buds, polyphenol oxidase, ATP synthase subunit beta, and actin are up-regulated. It was predicted that male sterility in NA3 might be related to energy metabolism turbulence, excessive ethylene synthesis, and suffocation of starch synthesis. The present study lays a foundation for future investigations of gene functions associated with pollen development and cytoplasmic male sterility, and explores the molecular mechanism of CMS in pepper. PMID:24264042

Wu, Zhiming; Cheng, Jiaowen; Qin, Cheng; Hu, Zhiqun; Yin, Caixia; Hu, Kailin

2013-01-01

153

Differential proteomic analysis of anthers between cytoplasmic male sterile and maintainer lines in Capsicum annuum L.  

PubMed

Cytoplasmic male sterility (CMS), widely used in the production of hybrid seeds, is a maternally inherited trait resulting in a failure to produce functional pollen. In order to identify some specific proteins associated with CMS in pepper, two-dimensional gel electrophoresis (2-DE) was applied to proteomic analysis of anthers/buds between a CMS line (designated NA3) and its maintainer (designated NB3) in Capsicum annuum L. Thirty-three spots showed more than 1.5-fold in either CMS or its maintainer. Based on mass spectrometry, 27 spots representing 23 distinct proteins in these 33 spots were identified. Proteins down-regulated in CMS anthers/buds includes ATP synthase D chain, formate dehydrogenase, alpha-mannosidas, RuBisCO large subunit-binding protein subunit beta, chloroplast manganese stabilizing protein-II, glutathione S-transferase, adenosine kinase isoform 1T-like protein, putative DNA repair protein RAD23-4, putative caffeoyl-CoA 3-O-methyltransferase, glutamine synthetase (GS), annexin Cap32, glutelin, allene oxide cyclase, etc. In CMS anthers/buds, polyphenol oxidase, ATP synthase subunit beta, and actin are up-regulated. It was predicted that male sterility in NA3 might be related to energy metabolism turbulence, excessive ethylene synthesis, and suffocation of starch synthesis. The present study lays a foundation for future investigations of gene functions associated with pollen development and cytoplasmic male sterility, and explores the molecular mechanism of CMS in pepper. PMID:24264042

Wu, Zhiming; Cheng, Jiaowen; Qin, Cheng; Hu, Zhiqun; Yin, Caixia; Hu, Kailin

2013-01-01

154

Sexual Function in Males After Radiotherapy for Rectal Cancer  

SciTech Connect

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.

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

2010-03-15

155

Sexual Orientation Related Differences in Cortical Thickness in Male Individuals  

PubMed Central

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

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

2014-01-01

156

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

PubMed

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

Engelke, T; Hirsche, J; Roitsch, T

2010-06-01

157

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

PubMed Central

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

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

2010-01-01

158

Characterization of the radish mitochondrial orfB locus: possible relationship with male sterility in Ogura radish  

Microsoft Academic Search

The orfB locus of the normal (fertile) and Ogura (male-sterile) radish mitochondrial genomes has been characterized in order to determine if this region, which has previously been correlated with cytoplasmic male sterility (CMS) in Brassica napus cybrids (Bonhomme et al. 1991; Temple et al. 1992), could also be involved in radish CMS. In normal radish, orfB is expressed as a

Subbiah Krishnasamy; Christopher A. Makaroff

1993-01-01

159

Tolerance of Low Temperature and Sterilizing Irradiation in Males of Glossina pallidipes (Diptera: Glossinidae).  

PubMed

Investigations into the possibility of using the chilled adult release system are continuing as an alternative method to the release of sterile tsetse flies, Glossina pallidipes Austen (Diptera: Glossinidae) in cardboard boxes. Exposing tsetse flies to 4°C for 6?h caused negligible mortality. A combination of chilling and irradiation resulted in reduced quantities of seminal contents being transferred to females. Mortality of flies after bulk irradiation was lower when a thermos flask was used than expanded polystyrene. Mortality after removal from cold storage increased with age. Flies that did not have a blood meal for 3 d prior to exposure to cold had a lower overnight survival than flies that were deprived of a blood meal for 1 or 2 d. Exposure of adult male tsetse flies to low temperature should be for as short a duration as is practical, so that the fitness of the released sterile flies is not unduly compromised. It is also necessary to ensure that losses are minimized during bulk irradiation of adult flies. It would be desirable to have minimal losses after the combined effects of irradiation, cold, and transportation, such that a sufficient number of sterile male flies will still be available to successfully compete for mating opportunities with wild females. PMID:25527576

Mutika, Gratian Nyambirai; Parker, Andrew Gordon

2014-01-01

160

Female sexual assault: the impact on the male significant other.  

PubMed

In this existential-phenomenological investigation five men were interviewed about their experience of being a male significant other (MSO) of a female sexual assault victim. The purpose of the study was to understand the MSO's meaning of the rape and the emotional impact it had on him. The thematic structure of a man's response to having a female significant other sexually assaulted depicts an impact on his emotional life in four significant areas: (1) his immediate painful thoughts and feelings, (2) his relationship with the victim, (3) his world view on male attitudes, and (4) the long-term effects of the trauma. It is an experience that has left him feeling angry, helpless, and guilty, prompted him to self-inspection, and thus changed him forever. PMID:15962921

Smith, Marilyn E

2005-01-01

161

SRY alone can induce normal male sexual differentiation  

SciTech Connect

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.

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

1995-01-30

162

Evaluation of a Treatment Program for Sexually Abused Adult Males  

Microsoft Academic Search

This study evaluated the effectiveness of an individual treatment program for five adult males who experienced childhood sexual abuse. A treatment manual focusing on abuse-related self-blame, anger, and anxiety was developed. Daily self-blame, anger, and anxiety self-ratings were completed before and throughout treatment. A multiple-baseline approach was used to evaluate treatment effects. Overall findings indicated that most participants experienced significant

Elisa Romano; Rayleen V. De Luca

2006-01-01

163

Analysis of Cytoplasmic Effects and Fine-Mapping of a Genic Male Sterile Line in Rice  

PubMed Central

Cytoplasm has substantial genetic effects on progeny and is important for yield improvement in rice breeding. Studies on the cytoplasmic effects of cytoplasmic male sterility (CMS) show that most types of CMS have negative effects on yield-related traits and that these negative effects vary among CMS. Some types of genic male sterility (GMS), including photo-thermo sensitive male sterility (PTMS), have been widely used in rice breeding, but the cytoplasmic effects of GMS remain unknown. Here, we identified a GMS mutant line, h2s, which exhibited small, white anthers and failed to produce mature pollen. Unlike CMS, the h2s had significant positive cytoplasmic effects on the seed set rate, weight per panicle, yield, and general combining ability (GCA) for plant height, seed set rate, weight per panicle, and yield. These effects indicated that h2s cytoplasm may show promise for the improvement of rice yield. Genetic analysis suggested that the phenotype of h2s was controlled by a single recessive locus. We mapped h2s to a 152 kb region on chromosome 6, where 22 candidate genes were predicted. None of the 22 genes had previously been reported to be responsible for the phenotypes of h2s. Sequencing analysis showed a 12 bp deletion in the sixth exon of Loc_Os06g40550 in h2s in comparison to wild type, suggesting that Loc_Os06g40550 is the best candidate gene. These results lay a strong foundation for cloning of the H2S gene to elucidate the molecular mechanism of male reproduction. PMID:23613915

Li, Yuanyuan; Ma, Bingtian; Li, Shigui

2013-01-01

164

Forensic medical aspects of male-on-male rape and sexual assault in greater Manchester.  

PubMed

Male-on-male rapes and sexual assaults comprise fewer than 10% of such assaults reported to the police, and so many physicians seldom encounter them. This paper provides an overview of the nature of sexual assault encountered by males, ensuing injuries, and comparisons with male-on-female assault cases. The retrospective epidemiological study was on two cohorts seen at St. Mary's Sexual Assault Referral Centre, Manchester. The participants were Centre clients seen between October 1986 and mid-May 2003; 376 male eases (370 individual clients) and 7,789 female cases (7,403 individual clients). The main outcome measure was the presence of injury (abrasion, laceration, or bruise) to defined body areas. The results showed that 66% of male cases (when assault type was known) had been raped, significantly fewer than in female cases, (p 0.00, a 0.05, O.R. 0.474, 95% C.I. 0.357 to 0.63). Eighteen per cent of male cases that had a forensic medical examination presented with an anal injury, significantly more than in females (p 0.00, a 0.05, O.R. 6.101, 95% C.I. 4.216 to 8.829). Significantly fewer males than females sustained injuries to other body areas. The conclusion was that males were significantly more likely (six times) than females to receive at least one injury to the anal area. Even so, males are five times more likely to have no anal injury. PMID:15176630

McLean, Iain A; Balding, Val; White, Cath

2004-04-01

165

Sexually dimorphic RB inactivation underlies mesenchymal glioblastoma prevalence in males  

PubMed Central

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

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

2014-01-01

166

[The stress effect in the prenatal period on sexual excitation and sexual orientation of the mice males].  

PubMed

Estrus female behind holed transparent partition produced sexual motivation and sexual arousal in males. It was manifested in behavioral changes (an increase in time spent near the partition) and the testosterone level augmentation in blood. Female mice were exposed to stress (1 h/day restraint) in the last week of gestation. Prenatal stress was shown to decrease the blood corticosterone level as well as to diminish sexual motivation and sexual arousal in adult male mice. Estrus female exposure produced a lesser behavioral response and a lesser testosterone level augmentation. No changes in weight of testicles, seminal vesicles or adrenal glands were found, but preputial gland weight increased. In prenatally stressed males, a female preference decrease and a male preference increase were revealed in the partner preference test. These data suggest that prenatal stress decreases sexual motivation in males and leads to clear predisposition to homosexuality, although it does not produce complete inversion of sexual orientation. PMID:16613063

Kuznetsova, E G; Amstislavskaia, T G; Bulygina, V V; Popova, N K

2006-01-01

167

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

PubMed

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. PMID:25262227

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

168

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

PubMed Central

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

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

2013-01-01

169

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

PubMed

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

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

2014-02-25

170

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

Microsoft Academic Search

This paper presents interview data and media analysis on the gay male community in the USA. It describes how sexual objectification is more than the outcome of racism in the gay male community. Sexual objectification of gay men of colour in the USA produces a white sexual community. Ideologies of inclusivity and non?discrimination blind white gay men to the harmful

Niels Teunis

2007-01-01

171

Male sexual harassment and female schooling behaviour in the eastern mosquitofish  

E-print Network

Male sexual harassment and female schooling behaviour in the eastern mosquitofish MARCO DADDA harassment is often intense and is costly for females. In Gambusia holbrooki, sexual harassment can greatly behaviour is a flexible strategy and that male sexual harassment may represent an important factor

Pilastro, Andrea

172

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

PubMed

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

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

2009-03-01

173

Attachment styles and sexual dysfunctions: a case-control study of female and male sexuality.  

PubMed

The aim of this study was to investigate attachment styles in a group of women and men with sexual dysfunction. We recruited 44 subjects (21 women and 23 men) with sexual dysfunction and 41 subjects (21 women and 20 men) with healthy sexual function as the control group. Validated instruments for the evaluation of male and female sexual dysfunctions (M/F SD) and a psychometric tool specifically designed to investigate attachment style were administered. In women, significant differences were found between subjects with sexual dysfunction and healthy controls. The scales indicating an insecure attachment showed: discomfort with closeness (FSD=42.85±11.55 vs CTRL=37.38±8.54; P<0.01), relationship as secondary (FSD=26.76±2.60 vs CTRL=18.42±7.99; P<0.01), and need for approval (FSD=26.38±3.61 vs CTRL=20.76±7.36; P<0.01). Healthy women also had significantly higher scores in secure attachment (confidence: FSD=24.57±3.89 vs CTRL=33.42±5.74; P<0.01). Men with sexual dysfunctions differed from healthy men in confidence (MSD=30±6.33 vs CTRL=36.05±5.26; P<0.01) and in discomfort with closeness (MSD=39.08±8 vs CTRL=34.25±7.54; P<0.05). These results suggest that particular aspects related to insecure attachment have a determinant role in people with sexual dysfunctions. It is therefore fundamental to identify the attachment styles and relational patterns in patients receiving counselling and psychological treatments focussed on sexual problems.International Journal of Impotence Research advance online publication, 14 August 2014; doi:10.1038/ijir.2014.33. PMID:25119586

Ciocca, G; Limoncin, E; Di Tommaso, S; Mollaioli, D; Gravina, G L; Marcozzi, A; Tullii, A; Carosa, E; Di Sante, S; Gianfrilli, D; Lenzi, A; Jannini, E A

2014-08-14

174

Analysis of differentially expressed genes in genic male sterility cotton (Gossypium hirsutum L.) using cDNA-AFLP.  

PubMed

cDNA amplified fragment length polymorphism (cDNA-AFLP) analysis was used to investigate the differentially expressed genes between sterile and fertile plants of ms5ms6 double-recessive genic male sterility (GMS) two-type line cotton (Gossypium hirsutum L.) at different stages, i.e., sporogenous cell stage, pollen mother cell (PMC) stage, and pollen grain stage. Seventeen differentially expressed fragments were identified. Functional analysis indicated that their corresponding genes may participate in the processes of signal transduction, transcription, energy metabolism, and plant cell wall development. Northern blot demonstrated the credibility of the result of cDNA-AFLP. A sterility restorer factor-like gene, which only expressed in fertile anther and was notably homologous to T cytoplasm male sterility restorer factor 2 of maize (Zea mays L.), was identified in this research. PMID:17601613

Ma, Xiaoding; Xing, Chaozhu; Guo, Liping; Gong, Yangcang; Wang, Hailin; Zhao, Yunlei; Wu, Jianyong

2007-06-01

175

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

PubMed

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

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

2012-10-01

176

Production of engineered long-life and male sterile Pelargonium plants  

PubMed Central

Background Pelargonium is one of the most popular garden plants in the world. Moreover, it has a considerable economic importance in the ornamental plant market. Conventional cross-breeding strategies have generated a range of cultivars with excellent traits. However, gene transfer via Agrobacterium tumefaciens could be a helpful tool to further improve Pelargonium by enabling the introduction of new genes/traits. We report a simple and reliable protocol for the genetic transformation of Pelargonium spp. and the production of engineered long-life and male sterile Pelargonium zonale plants, using the pSAG12::ipt and PsEND1::barnase chimaeric genes respectively. Results The pSAG12::ipt transgenic plants showed delayed leaf senescence, increased branching and reduced internodal length, as compared to control plants. Leaves and flowers of the pSAG12::ipt plants were reduced in size and displayed a more intense coloration. In the transgenic lines carrying the PsEND1::barnase construct no pollen grains were observed in the modified anther structures, which developed instead of normal anthers. The locules of sterile anthers collapsed 3–4?days prior to floral anthesis and, in most cases, the undeveloped anther tissues underwent necrosis. Conclusion The chimaeric construct pSAG12::ipt can be useful in Pelargonium spp. to delay the senescence process and to modify plant architecture. In addition, the use of engineered male sterile plants would be especially useful to produce environmentally friendly transgenic plants carrying new traits by preventing gene flow between the genetically modified ornamentals and related plant species. These characteristics could be of interest, from a commercial point of view, both for pelargonium producers and consumers. PMID:22935247

2012-01-01

177

Causes of male sexual trait divergence in introduced populations of guppies  

PubMed Central

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

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

2014-01-01

178

Comparisons among two fertile and three male-sterile mitochondrial genomes of maize.  

PubMed

We have sequenced five distinct mitochondrial genomes in maize: two fertile cytotypes (NA and the previously reported NB) and three cytoplasmic-male-sterile cytotypes (CMS-C, CMS-S, and CMS-T). Their genome sizes range from 535,825 bp in CMS-T to 739,719 bp in CMS-C. Large duplications (0.5-120 kb) account for most of the size increases. Plastid DNA accounts for 2.3-4.6% of each mitochondrial genome. The genomes share a minimum set of 51 genes for 33 conserved proteins, three ribosomal RNAs, and 15 transfer RNAs. Numbers of duplicate genes and plastid-derived tRNAs vary among cytotypes. A high level of sequence conservation exists both within and outside of genes (1.65-7.04 substitutions/10 kb in pairwise comparisons). However, sequence losses and gains are common: integrated plastid and plasmid sequences, as well as noncoding "native" mitochondrial sequences, can be lost with no phenotypic consequence. The organization of the different maize mitochondrial genomes varies dramatically; even between the two fertile cytotypes, there are 16 rearrangements. Comparing the finished shotgun sequences of multiple mitochondrial genomes from the same species suggests which genes and open reading frames are potentially functional, including which chimeric ORFs are candidate genes for cytoplasmic male sterility. This method identified the known CMS-associated ORFs in CMS-S and CMS-T, but not in CMS-C. PMID:17660568

Allen, James O; Fauron, Christiane M; Minx, Patrick; Roark, Leah; Oddiraju, Swetha; Lin, Guan Ning; Meyer, Louis; Sun, Hui; Kim, Kyung; Wang, Chunyan; Du, Feiyu; Xu, Dong; Gibson, Michael; Cifrese, Jill; Clifton, Sandra W; Newton, Kathleen J

2007-10-01

179

Movement of sterile male Bactrocera cucurbitae (Diptera: Tephritidae) in a Hawaiian agroecosystem.  

PubMed

The melon fly, Bactrocera cucurbitae Coquillett, invaded the Hawaiian Island chain in 1895. In 1999, a program sponsored by the USDA-ARS to control melon fly and other tephritid pests in Hawaii over a wide area was initiated on the islands of Hawaii, Maui, and Oahu. To control these flies in an areawide setting, understanding how flies move within the landscape is important. To explore the movement of this fly, we examined the movement of marked, male, sterile, laboratory-reared B. cucurbitae on the island of Hawaii in an agricultural setting. Two releases of dyed, sterile flies consisting of approximately 15,000 flies, were released 6 wk apart. Released flies were trapped back by using Moroccan traps baited with a male attractant. These two releases suggest that in the Hawaiian agricultural areas where the areawide control is being sought, melon flies do not move extensively when there are abundant larval host and adult roosting sites. Over the course of this study, only one fly made it the maximum distance that we could detect fly movement (approximately 2,000 m in 2 wk). From these data, it seems that the flies dispersed throughout the study area but then moved very little thereafter. This is very apparent in the second release where the recovery rate after the second week was still fairly high, suggesting that if there are plenty of host fields and roosting sites the flies are unlikely to move. PMID:16334322

Peck, Steven L; McQuate, Grant T; Vargas, Roger I; Seager, Dennis C; Revis, Hannah C; Jang, Eric B; McInnis, Don O

2005-10-01

180

Cytoplasmic male sterility in barley: Evidence for the involvement of cytokinins in fertility restoration  

PubMed Central

The hypothesis of the association between an increase in cytokinin activity and restoration of anther fertility in msm1 cytoplasm was tested. The following barley lines with Hordeum vulgare cv. Adorra nuclear gene background were studied: Adorra cytoplasm without nuclear restorer gene (fertile), Adorra cytoplasm homozygous for nuclear Rfm1a gene (fertile), msm1 cytoplasm without restorer gene (male sterile), msm1 cytoplasm homozygous for nuclear Rfm1a gene (fertile). Ethanolic extracts of root exudate were fractionated and bioassayed for cytokinins. Both the biological activity and the total quantity of cytokinins appeared lowest in the unrestored male sterile line. The total biological activities of cytokinins in the three fertile lines were similar, but the quantities in the restorer gene carriers appeared lower. On the other hand, the restorer gene carriers, independent of the cytoplasm, showed 8-9 times more of a bound cytokinin. Because the bound form is evidently underestimated by the bioassay, the increase in the bound cytokinin fraction may mean even a higher total content in the Rfm1a gene carriers than in Adorra without the gene. The bound cytokinin may be translocated more readily to distal organs (e.g., the anthers) compared with unbound cytokinins. Because cytokinins are associated with various ecophysiological processes, the rise in a particular form may explain the heterogeneous distribution of the restorer gene in wild barley populations in different regions of Israel. PMID:16593259

Ahokas, Hannu

1982-01-01

181

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

PubMed

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. PMID:23256151

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

2013-01-01

182

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

PubMed

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

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

2014-06-01

183

Analysis of Differentially Expressed Genes in Genic Male Sterility Cotton ( Gossypium hirsutum L.) Using cDNA-AFLP  

Microsoft Academic Search

cDNA amplified fragment length polymorphism (cDNA-AFLP) analysis was used to investigate the differentially expressed genes between sterile and fertile plants of ms5ms6 double-recessive genic male sterility (GMS) two-type line cotton (Gossypium hirsutum L.) at different stages, i.e., sporogenous cell stage, pollen mother cell (PMC) stage, and pollen grain stage. Seventeen differentially expressed fragments were identified. Functional analysis indicated that their

Xiaoding Ma; Chaozhu Xing; Liping Guo; Yangcang Gong; Hailin Wang; Yunlei Zhao; Jianyong Wu

2007-01-01

184

Masculinization of Gene Expression Is Associated with Exaggeration of Male Sexual Dimorphism  

PubMed Central

Gene expression differences between the sexes account for the majority of sexually dimorphic phenotypes, and the study of sex-biased gene expression is important for understanding the genetic basis of complex sexual dimorphisms. However, it has been difficult to test the nature of this relationship due to the fact that sexual dimorphism has traditionally been conceptualized as a dichotomy between males and females, rather than an axis with individuals distributed at intermediate points. The wild turkey (Meleagris gallopavo) exhibits just this sort of continuum, with dominant and subordinate males forming a gradient in male secondary sexual characteristics. This makes it possible for the first time to test the correlation between sex-biased gene expression and sexually dimorphic phenotypes, a relationship crucial to molecular studies of sexual selection and sexual conflict. Here, we show that subordinate male transcriptomes show striking multiple concordances with their relative phenotypic sexual dimorphism. Subordinate males were clearly male rather than intersex, and when compared to dominant males, their transcriptomes were simultaneously demasculinized for male-biased genes and feminized for female-biased genes across the majority of the transcriptome. These results provide the first evidence linking sexually dimorphic transcription and sexually dimorphic phenotypes. More importantly, they indicate that evolutionary changes in sexual dimorphism can be achieved by varying the magnitude of sex-bias in expression across a large proportion of the coding content of a genome. PMID:23966876

Pointer, Marie A.; Harrison, Peter W.; Wright, Alison E.; Mank, Judith E.

2013-01-01

185

Photosynthetic characteristics of leaves of male-sterile and hermaphrodite sex types of Plantago lanceolata grown under conditions of contrasting nitrogen and light availabilities  

Microsoft Academic Search

Plantago lanceolata is it gynodioecious species: In natural populations male steriles (MS) coexist with hermaphrodites (H). Since male steriles have a reproductive disadvantage, without any compensation for their loss in male function by an increase in female function, they are expected to disappear from the population. In this study we investigated the possibility that differences in ecologically important photosynthetic characteristics,

Pieter Poot; Jorn Pilon; Pens L. T

1996-01-01

186

Male sexual differentiation in mice lacking H-Y antigen.  

PubMed

The sexual phenotype of an adult mammal depends on whether the fetal gonad has differentiated as a testis or as an ovary. Because individuals of XY or XXY sex chromosome constitution develop as males, while XX and XO individuals develop as females, the presence of a Y chromosome seems normally to be required for testis differentiation and its absence to be necessary for differentiation of an ovary. The nature of the hypothetical Y-dependent substance responsible for masculinization of the indifferent gonad has been a matter for debate. A male-specific transplantation antigen, H-Y, has been known for many years and more recently a serologically detected antigen, also male-specific, has been reported. Those who believe that the two are antigenically distinct refer to the latter as SDM (serologically detected male) antigen, but many refer to both as H-Y antigen. The hypothesis that H-Y is itself the Y-dependent testis inducer, although supported by little or no direct evidence, is economical and hence attractive. H-Y antigen is frequently stated to be the substance responsible for primary sex determination (for example, see ref. 11). We report here that H-Y is absent from certain mice that develop testes and are of indisputably male phenotype, hence this transplantation antigen is unlikely to be responsible for testis determination. PMID:6542174

McLaren, A; Simpson, E; Tomonari, K; Chandler, P; Hogg, H

187

The male-sterility polymorphism of Silene vulgaris: analysis of genetic dat from two populations and comparison with Thymus vulgaris.  

PubMed Central

Results are given of genetic studies of male sterility using plants from two natural populations from Sussex, England. Both populations have substantial frequencies of females, approximately 0.25 in population 1 and 0.60 in population 3. As in the few other gynodioecious populations studied in detail, many genetic factors are present. In population 1, there are at least two, and more likely three, different cytoplasmic types, one of which appears to produce male sterility in progeny from any hermaphrodite pollen donor; in other words restorer alleles for this cytoplasm are rare or absent from the population. The other two populations can be carried in hermaphrodites that have the dominant restorers. In population 1, there are also probably three restorer loci with complementary recessive male-sterility alleles, as well as a locus with duplicate action, which cannot produce male sterility unless the plant is also homozygous for the recessive allele at another locus. The results from population 3 are quite similar, though there was no evidence in this population for an unrestored sterility cytoplasm. A similar joint nucleocytoplasmic model with multiple restorers fits data from Thymus vulgaris. PMID:9799278

Charlesworth, D; Laporte, V

1998-01-01

188

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

PubMed Central

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

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

2013-01-01

189

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

PubMed Central

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

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

2012-01-01

190

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

E-print Network

+/resc- (sterilizer/non-rescuer). To date, the first three have been discovered7­9. If one envisages mitochondria the ability to rescue their own sterilizing effect, one might speculate that mitochondria possess the same function. Some cases of sterility (more precisely, cases where sterility is the result of early embryonic

Johnson, Kevin P.

191

Exploring urban male non-marital sexual behaviours in Pakistan  

PubMed Central

Background In Pakistan, sexual practices outside marriage are proscribed by law. We aimed to assess the range and magnitude of non-marital sexual behaviours of urban men, focusing on men having sex with men. Methods In this cross sectional survey undertaken in six cities of Pakistan, we interviewed 2400 men aged 16–45 years selected through a multistage systematic sampling design. Sexual behaviours were assessed through a structured questionnaire. Multivariable analysis was used to identify association between various individual level characteristics and probability of engaging in sexual activities involving men. Results Nearly one-third (29 percent) reported having had non-marital sex in their lifetime. Of these men 16 percent reported premarital sex, while 11 percent reported engaging in both pre- and extramarital sex. Only two percent reported exclusive extramarital sex. In total 211 respondents, 9 percent reported ever having had sexual relations with men. While 62 respondents, 2.6 percent reported exclusive sex with males. Factors that were significantly associated with MSM behaviours were being less than 27 years (adjusted OR 5.4, 95% CI 3.8–7.7, p?sexual debut at a younger age i.e. 16–22 years (adjusted OR 12.5, 95% CI: 3.8–40.7, p?

2013-01-01

192

Effect of acclimation to outdoor condition on the sexual performance of mass-produced Medflies (Diptera: Tephritidae)  

Microsoft Academic Search

Application of the sterile insect technique (SIT) as part of integrated area-wide programs to control the Mediterranean fruit fly (medfly) Ceratitis capitata (Wiedemann) require that the released males attract wild females and transfer sterile sperm. However, knowledge about male sexual performance after they are released is scarce. We conducted a study to evaluate male sexual performance in field cage tests,

R. Pereira; N. Silva; C. Quintal; R. Abreu; J. Andrade; L. Dantas

2007-01-01

193

Metabolism of reactive oxygen species in cytoplasmic male sterility of rice by marking upmost pulvinus interval.  

PubMed

Reactive oxygen species (ROS) and malondialdehyde (MDA) in plant cell are thought to be important inducible factors of cell apoptosis if excessively accumulated in cells. To elucidate the metabolic mechanism of MDA production and scavenging in the cytoplasmic male-sterile (CMS) rice, CMS line and maintainer were employed for studying the relationship at different developmental stages by marking upmost pulvinus interval method of experiment. The results showed that the panicles and leaves of the CMS line had a noticeable higher MDA content than those of maintainer line at all five stages that had been investigated (p?sterile panicles and leaves had inducible effects on the enzymic activity of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). However, at the abortion peak stage, MDA was excessively accumulated and antioxidant enzymic activity reduced significantly, resulting in the generation and scavenging of MDA out of balance. PMID:25380642

Li, Jianxin; Dai, Ximei; Li, Linyu; Jiao, Zhen; Huang, Qunce

2015-02-01

194

Prerelease exposure to methyl eugenol increases the mating competitiveness of sterile males of the oriental fruit fly (Diptera: Tephritidae) in a Hawaiian orchard.  

PubMed

Males of the oriental fruit fly, Bactrocera dorsalis (Hendel), are strongly attracted to methyl eugenol (ME), and recent work demonstrated that ingestion of this chemical enhances male mating success, apparently owing its role as a precursor in the synthesis of the male sex pheromone. The current study expanded upon earlier laboratory and field-cage experiments by assessing whether prerelease exposure to ME increased the mating competitiveness of mass-reared, sterile males in Hawaiian orchards. Releases of sterile males from a pupal color-based sexing strain were made weekly in two fruit orchards over 8 mo, with the sterile males at one site given ME for 24 h before release (treated) and the sterile males at the other site given no ME before release (control). Fruits were collected periodically during the study period, and eggs were dissected and incubated to score hatch rate. At both sites, releases of sterile males increased the proportion of unhatched eggs well above prerelease levels, but the incidence of egg sterility was consistently, and statistically, greater in the orchard receiving ME-exposed males. Computed over the entire release period, the average value of Fried's competitive index (that characterizes the mating success of sterile males relative to their wild counterparts) for ME-treated males was 3.5 times greater than that for control males, although this difference was not statistically significant. However, when computed over the period during which egg sterility values were elevated and stable, presumably when females inseminated before the releases were rare or absent, the competitive indices were significantly higher for ME-treated sterile males. The implications of these results for implementing the Sterile Insect Technique against this species are discussed. PMID:22299359

McInnis, D; Kurashima, R; Shelly, T; Komatsu, J; Edu, J; Pahio, E

2011-12-01

195

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

PubMed

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. PMID:21479555

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

2011-07-01

196

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

ERIC Educational Resources Information Center

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…

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

2011-01-01

197

Sexpectations: Male College Students' Views about Displayed Sexual References on Females' Social Networking Web Sites  

PubMed Central

Study Objective Sexual reference display on a social networking web site (SNS) is associated with self-reported sexual intention; females are more likely to display sexually explicit content on SNSs. The purpose of this study was to investigate male college students' views towards sexual references displayed on publicly available SNSs by females. Design Focus groups Setting One large state university Participants Male college students age 18–23 Interventions All tape recorded data was fully transcribed, then discussed to determine thematic consensus. Main Outcome Measures A trained male facilitator asked participants about views on sexual references displayed on SNSs by female peers and showed examples of sexual references from female's SNS profiles to facilitate discussion. Results A total of 28 heterosexual male participants participated in 7 focus groups. Nearly all participants reported using Facebook to evaluate potential female partners. Three themes emerged from our data. First, participants reported that displays of sexual references on social networking web sites increased sexual expectations. Second, sexual reference display decreased interest in pursuing a dating relationship. Third, SNS data was acknowledged as imperfect but valuable. Conclusion Females who display sexual references on publicly available SNS profiles may be influencing potential partners' sexual expectations and dating intentions. Future research should examine females' motivations and beliefs about displaying such references, and educate women about the potential impact of these sexual displays. PMID:21190872

Moreno, Megan A.; Swanson, Michael J.; Royer, Heather; Roberts, Linda J.

2011-01-01

198

MALE-BIASED NECTAR PRODUCTION IN A PROTANDROUS HERB MATCHES PREDICTIONS OF SEXUAL SELECTION THEORY  

E-print Network

MALE-BIASED NECTAR PRODUCTION IN A PROTANDROUS HERB MATCHES PREDICTIONS OF SEXUAL SELECTION THEORY success. In such cases, sexual selection is often suggested as the cause of asymmetric benefits, yet sexual selection in plants--particularly plants with hermaphroditic flowers--is infrequently tested

Carlson, Jane E.

199

Mediterranean fruit flies: sterility and sexual competitiveness in the laboratory after treatment with gamma irradiation in air, carbon dioxide, helium, nitrogen, or partial vacuum  

Microsoft Academic Search

The level of sterility of males of Ceratitis capitata (Wiedemann) was similar when a given dose of gamma irradiation was applied to pupae in atmospheres of nitrogen, carbon dioxide or helium or in a partial vacuum. A dose of 10 krad in air was sufficient to produce 99.5 percent sterility in males; a dose of 16 krad was required to

K. Ohinata; M. Ashraf; E. J. Harris

1977-01-01

200

A comparison of the vegetative growth of male-sterile and hermaphroditic lines of Plantago lanceolata in relation to N supply  

Microsoft Academic Search

Gynodioecy is a dimorphic breeding system in which hermaphrodites coexist with male steriles in natural populations. Theoretical models predict that without any compensation in female fitness, male steriles will quickly disappear from a population. The amount of compensation required depends upon the mode of inheritance. In this study we investigated whether performance, during early vegetative growth, could play a role

PIETER POOT; TOMMY VAN DEN BROEK; JOS M. M. VAN DAMME; HANS LAMBERS

1997-01-01

201

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

202

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

Microsoft Academic Search

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

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

1994-01-01

203

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

PubMed Central

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

2014-01-01

204

The transfer of ‘Polima’ cytoplasmic male sterility from oilseed rape ( Brassica napus ) to broccoli ( B. oleracea ) by protoplast fusion  

Microsoft Academic Search

Protoplast fusion was utilised to transfer Polima type cytoplasmic male sterility (CMS) from Brassica napus, canola cv. Polima Karat (Pol-Karat) to B. oleracea, broccoli, var. “Green Comet”. Southern and RFLP analysis confirmed that four cybrids possessed nuclear genomes of broccoli with Polima mitochondria and chloroplasts. A fifth cybrid was a nuclear hybrid between broccoli and Pol-Karat, with Polima mitochondria and

Stephen A. Yarrow; Laurie A. Burnett; Richard P. Wildeman; Roger J. Kemble

1990-01-01

205

Induction of cytoplasmic male sterility and fertility reversion by mutagenesis; negative evidence from a study on sugar beet  

Microsoft Academic Search

Attempts have been made to induce cytoplasmic male sterility (cms) and cytoplasmically inherited fertility reversion in sugar beet using various mutagenic agents by repeating techniques previously described. Despite the previous report of successful induction of cms and reversion at very high frequency it was not possible to repeat this success. Analysis of M2 plants at the DNA level demonstrated no

Timothy Brears; David M. Lonsdale

1990-01-01

206

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

Microsoft Academic Search

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

Fernand Vedel; Chantal Mathieu

1983-01-01

207

Male-male contests for mates, sexual size dimorphism, and sex ratio in a natural population of a solitary parasitoid.  

PubMed

Understanding how different behavioural and life history traits interact is fundamental to developing ethological theory. Here we study the interaction of male-male competition for mates and sexual size dimorphism in a solitary wasp, with implications for sex allocation. In Hymenoptera, females are normally larger than males suggesting that males do not benefit as much as females from larger size. However, in our focal species, a solitary Eurytoma wasp, males compete for mates by pairwise contests at female emergence sites, suggesting that male size may strongly affect fitness. In contests observed in the field, larger males were more likely to win fights, and males fighting at female emergence sites were much larger than average males. Males showed higher variance in body size than females, such that all the smallest individuals were males, a majority of medium-to-large individuals were female, but the majority of largest individuals were male. Our data suggest that sexual size dimorphism in this species has been affected by intra-sexual selection for male size, which may have implications for sex allocation. PMID:23872503

Macedo, Margarete V; Monteiro, Ricardo F; Silveira, Mariana P; Mayhew, Peter J

2013-11-01

208

Generating Sexually Differentiated Vocal Patterns: Laryngeal Nerve and EMG Recordings from Vocalizing Male and Female African  

E-print Network

Vocalizing Male and Female African Clawed Frogs (Xenopus laevis) Ayako Yamaguchi and Darcy B. Kelley clawed frogs (Xenopus laevis) produce sexually dimorphic vocalizations; for males these include ad is the source of sexually differentiated vocalizations in Xenopus laevis. Fur- thermore, detailed analyses

Kelley, Darcy B.

209

Female Condition Influences Preferences for Sexual Dimorphism in Faces of Male Humans (Homo sapiens )  

Microsoft Academic Search

In some species, female condition correlates positively with preferences for male secondary sexual traits. Women's preferences for sexually dimorphic characteristics in male faces (facial masculinity) have recently been reported to covary with self-reported attractiveness. As women's attractiveness has been proposed to signal reproductive condition, the findings in human (Homo sapiens) and other species may reflect similar processes. The current study

I. S. Penton-Voak; A. C. Little; B. C. Jones; D. M. Burt; B. P. Tiddeman; D. I. Perrett

2003-01-01

210

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

ERIC Educational Resources Information Center

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 be at risk…

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

2008-01-01

211

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

PubMed Central

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

Carrillo, Héctor; Fontdevila, Jorge

2010-01-01

212

The First Few Times: Similarities and Differences in Sexual Behaviors and Attitudes of West German Male and Female Adolescents.  

ERIC Educational Resources Information Center

The study reported in this paper examined: (1) how the expectations of sexual relationships relate to the sexual experiences which male and female adolescents gather in their relationships with the opposite sex; and (2) whether male and female adolescents differ in their sexual behavior, their expectations for sexual relationships, their…

Oswald, Hans; von Salisch, Maria

213

Male-female differences in the effects of cannabinoids on sexual behavior and gonadal hormone function.  

PubMed

The putative role of the endocannabinoid system and the effects of cannabis use in male and female sexual functioning are summarized. The influence of cannabis intake on sexual behavior and arousability appear to be dose-dependent in both men and women, although women are far more consistent in reporting facilitatory effects. Furthermore, evidence from nonhuman species indicate somewhat more beneficial than debilitating effects of cannabinoids on female sexual proceptivity and receptivity while suggesting predominantly detrimental effects on male sexual motivation and erectile functioning. Data from human and nonhuman species converge on the ephemeral nature of THC-induced testosterone decline. However, it is clear that cannabinoid-induced inhibition of male sexual behavior is independent of concurrent declines in testosterone levels. Investigations also reveal a suppression of gonadotropin release by cannabinoids across various species. Historical milestones and promising future directions in the area of cannabinoid and sexuality research are also outlined in this review. PMID:19733173

Gorzalka, Boris B; Hill, Matthew N; Chang, Sabrina C H

2010-06-01

214

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

PubMed

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

Teunis, Niels

2007-01-01

215

Do male barn swallows ( Hirundo rustica ) experience a trade-off between the expression of multiple sexual signals?  

Microsoft Academic Search

Some sexual selection models envisage exaggerated male secondary sexual characters to be costly and therefore reliable indicators of the quality of potential mates to choosy females. If male secondary sexual characters have a natural selection cost, they may be linked to each other by reciprocally constraining relationships that would prevent individual males from increasing their level of multiple signaling. Barn

Nicola Saino; Maria Romano; Roberto Sacchi; Paola Ninni; Paolo Galeotti; Anders Pape Møller

2003-01-01

216

‘Most of Us Guys are Raring to Go Anytime, Anyplace, Anywhere’: Male and Female Sexuality in Cleo and Cosmo  

Microsoft Academic Search

Women’s magazines are a popular site for analysis of socio-cultural messages about gender, sex, and sexuality. We analyzed six consecutive issues of Cosmopolitan and Cleo to identify the ways in which they construct and represent male and female sexuality. Overall, male sexuality was prioritised, ‘real’ heterosex was depicted as penetrative, and orgasm was given precedence. Two main accounts of male

Panteá Farvid; Virginia Braun

2006-01-01

217

[Sexual dissatisfaction and somatic complaints in male infertility].  

PubMed

Several relevant sociodemographic and psychological variables were assessed in addition to clinical and andrological examinations in order to find predictors for sexual satisfaction and somatisation in 68 infertile men of involuntarily childless couples. Subjects reported relatively high average levels of both sexual satisfaction and somatisation, with considerable variance between subjects. Multiple regression analyses revealed that neither age, attitudes towards sexuality, nor andrological findings had an influence on sexual satisfaction. However, an inverse relationship between sexual satisfaction and somatisation was found. Furthermore, a short-lasting partnership and high sexual dissatisfaction prior to the diagnosis of infertility could be unveiled as risk factors for somatisation in infertile men. These results propose state and trait characteristics of sexual satisfaction and suggest a buffering role of longer lasting and sexually satisfying partnerships with respect to the distress of infertility. The promising results need confirmation by repeated investigation. Other possible influences, e.g. styles of coping, should be included in future studies. PMID:10488646

Schilling, G; Müller, M J; Haidl, G

1999-08-01

218

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

PubMed Central

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. PMID:11296864

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

2001-01-01

219

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

PubMed Central

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

Wang, Qi; Shih, Chungkun; Ren, Dong

2013-01-01

220

Sexual Behavior among Employed Male Rural Migrants in Shanghai, China  

ERIC Educational Resources Information Center

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…

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

2006-01-01

221

Characterization of a novel thermosensitive restorer of fertility for cytoplasmic male sterility in maize.  

PubMed

S-type cytoplasmic male sterility (CMS-S) in maize is associated with high levels of a 1.6-kb RNA in mitochondria. This RNA contains two chimeric open reading frames (ORFs), orf355 and orf77. The previously described nuclear restorer-of-fertility allele Rf3 causes the processing of all transcripts that contain these chimeric ORFs. The Lancaster Surecrop-derived inbred line A619 carries a restorer that is distinct from Rf3 in that it selectively reduces only the CMS-S-specific 1.6-kb RNA. We have found that 10 additional Lancaster lines carry a single restoring allele traceable to either of two inbred lines, C103 and Oh40B. The C103 and Oh40B restorers are allelic to each other, but not to Rf3. Thus, this restoring allele, designated Rf9, represents a second naturally occurring CMS-S restorer in maize. Rf9 is a less effective restorer of fertility than is Rf3; its expression is influenced by both inbred nuclear background and temperature. Rf9 acts to reduce the amounts of orf355/orf77-containing linear mitochondrial subgenomes, which are generated by recombination of circular subgenomes with CMS-S-specific linear plasmids. The 1.6-kb RNA, which is transcribed only from linear ends, is correspondingly reduced. PMID:19255365

Gabay-Laughnan, Susan; Kuzmin, Evgeny V; Monroe, Jessica; Roark, Leah; Newton, Kathleen J

2009-05-01

222

ms17: a meiotic mutation causing partial male sterility in a corn silage hybrid.  

PubMed

Cytological analysis under light microscopy of the single hybrid P30R50 of silage corn revealed an abnormal pattern of microsporogenesis that affected the meiotic products. Meiosis progressed normally until diakinesis, but before migration to the metaphase plate, bivalents underwent total desynapsis and 20 univalent chromosomes were scattered in the cytoplasm. At this stage, meiocytes also exhibited a number of chromatin-like fragments scattered throughout the cell. Metaphase I was completely abnormal in the affected cells, and univalent chromosomes and fragments were distributed among several curved spindles. Anaphase I did not occur, and each chromosome or group of chromosomes originated a micronucleus. After this phase, an irregular cytokinesis occurred, and secondary meiocytes with several micronuclei were observed. Metaphase II and anaphase II also did not occur, and after the second cytokinesis, the genomes were fractionated into polyads, generating several unbalanced microspores, with various-sized nuclei. About 35% of the tetrads were abnormal in the hybrid. This spontaneous mutation had been previously reported in a USA maize line called ms17 and was found to cause male sterility. PMID:21948758

Pagliarini, M S; Souza, V F; Silva, N; Scapim, C A; Rodovalho, M; Faria, M V

2011-01-01

223

A quantitative genetic analysis of nuclear-cytoplasmic male sterility in structured populations of Silene vulgaris.  

PubMed

Gynodioecy, the coexistence of functionally female and hermaphroditic morphs within plant populations, often has a complicated genetic basis involving several cytoplasmic male-sterility factors and nuclear restorers. This complexity has made it difficult to study the genetics and evolution of gynodioecy in natural populations. We use a quantitative genetic analysis of crosses within and among populations of Silene vulgaris to partition genetic variance for sex expression into nuclear and cytoplasmic components. We also use mitochondrial markers to determine whether cytoplasmic effects on sex expression can be traced to mitochondrial variance. Cytoplasmic variation and epistatic interactions between nuclear and cytoplasmic loci accounted for a significant portion of the variation in sex expression among the crosses. Source population also accounted for a significant portion of the sex ratio variation. Crosses among populations greatly enhanced the dam (cytoplasmic) effect, indicating that most among-population variance was at cytoplasmic loci. This is supported by the large among-population variance in the frequency of mitochondrial haplotypes, which also accounted for a significant portion of the sex ratio variance in our data. We discuss the similarities between the population structure we observed at loci that influence sex expression and previous work on putatively neutral loci, as well as the implications this has for what mechanisms may create and maintain population structure at loci that are influenced by natural selection. PMID:11404344

Taylor, D R; Olson, M S; McCauley, D E

2001-06-01

224

Restoring pollen fertility in transgenic male-sterile eggplant by Cre/loxp-mediated site-specific recombination system  

PubMed Central

This study was designed to control plant fertility by cell lethal gene Barnase expressing at specific developmental stage and in specific tissue of male organ under the control of Cre/loxP system, for heterosis breeding, producing hybrid seed of eggplant. The Barnase-coding region was flanked by loxP recognition sites for Cre-recombinase. The eggplant inbred/pure line (‘E-38') was transformed with Cre gene and the inbred/pure line (‘E-8') was transformed with the Barnase gene situated between loxp. The experiments were done separately, by means of Agrobacterium co-culture. Four T0 -plants with the Barnase gene were obtained, all proved to be male-sterile and incapable of producing viable pollen. Flowers stamens were shorter, but the vegetative phenotype was similar to wild-type. Five T 0 -plants with the Cre gene developed well, blossomed out and set fruit normally. The crossing of male-sterile Barnase-plants with Cre expression transgenic eggplants resulted in site-specific excision with the male-sterile plants producing normal fruits. With the Barnase was excised, pollen fertility was fully restored in the hybrids. The phenotype of these restored plants was the same as that of the wild-type. Thus, the Barnase and Cre genes were capable of stable inheritance and expression in progenies of transgenic plants. PMID:21637486

2010-01-01

225

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

PubMed Central

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 and peripheral mechanisms. These results thus support the traditional use of Arctium lappa L. root extract for treating impotence and sterility. PMID:22296876

2012-01-01

226

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

PubMed Central

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

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

2014-01-01

227

Predictors of male partner treatment for sexually transmitted infection  

PubMed Central

Background Patient-initiated notification is a commonly used practice for notifying sex partners of possible exposure to a sexually transmitted infection (STI), yet 46% to 75% of partners are never treated. The Contraceptive CHOICE Project (CHOICE) is a longitudinal cohort study of women that provides no-cost contraception, STI testing, treatment to participants, and free partner treatment. Our objective was to evaluate characteristics of women who tested positive for chlamydia, gonorrhea, or trichomoniasis, and their association with successful partner treatment. Methods We analyzed baseline survey and STI testing, notification, and treatment data from the first 5,087 participants enrolled in CHOICE. We considered “treated partners” to be men who received antibiotic treatment at the study clinic or by a prescription through the study. Independent predictors of successful partner treatment were identified using univariate analysis and multivariable analysis using Poisson regression with robust error variance. Results Forty-four percent of male partners were successfully treated. Women whose partners were less likely to obtain treatment were black (RRadj=0.6; 95% CI: 0.5–0.8) or reported some concern about future STI with the partner (RRadj=0.6; 95% CI: 0.4, 0.8). Women whose partners were more likely to receive treatment were living with their partner (RRadj=1.4; 95% CI: 1.1–1.8) or reported recent inconsistent condom use (RRadj=1.5; 95% CI: 1.1–2.1). Conclusions The male partner treatment rate resulting from female patient-initiated partner notification in our study was low. Our findings highlight the need to develop novel notification interventions that yield higher partner treatment rates and consider patient-specific factors, such as race and relationship status. PMID:23001263

Secura, Gina M.; Desir, Fidel A.; Mullersman, Jennifer L.; Madden, Tessa; Allsworth, Jenifer E.; Peipert, Jeffrey F.

2012-01-01

228

Sexually Coercive Behavior in Male Youth: Population Survey of General and Specific Risk Factors  

Microsoft Academic Search

Little is known about risk\\/protective factors for sexually coercive behavior in general population youth. We used a Swedish\\u000a school-based population survey of sexual attitudes and experiences (response rate 77%) and investigated literature-based variables\\u000a across sexually coercive (SEX), non-sexual conduct problem (CP), and normal control (NC) participants to identify general\\u000a and specific risk\\/protective factors for sexual coercion. Among 1,933 male youth,

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

2010-01-01

229

Ultrastructure of Male Sexual Apparatus of Scutellonema brachyurum  

PubMed Central

Electron micrographs of serial sections show that the male sexual apparatus of Scutellonema brachyurum includes two morphologically identical spicules. Each is composed of a swollen tubular head, crescentic shaft, and leaf-like blade with membranous velum expanded from the central trunk. The spicules are concave and grooved on the ventral side and convex on the dorsal side near the trunk. The trunk is continuous with the shaft and head. Nerve tissue occupies the core of the spicule and includes a dendritic process which gains access to the exterior via a small pore on the lateral side of the spicule tip. Three protractor and two retractor muscles are associated with each spicule. A sensory accessory piece connects with the tip of the gubernaculum and protrudes from the lower side of the opening of the spicular pouch; it protracts and retracts with the muscularized gubernaculum. The gubernaculum varies from bow-shaped in the distal part to boat-shaped in the mid region. A sac exits beneath the accessory piece as a buffer for its movement. A cuticular guiding bar originating from the dorsal wall of the spicular pouch has a tongue. The ventral surface of the tongue is sclerotized to separate the two spicules. It is mobile by muscles of the protractor gubernaculi, retractor gubernaculi, and seductor gubernaculi. PMID:19294122

Wang, K. C.; Chen, T. A.

1985-01-01

230

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

PubMed

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

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

2010-10-01

231

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...

232

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

PubMed

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 reproductive activity. PMID:14608499

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

2004-01-01

233

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

234

Sexual activity increases resistance against Pseudomonas entomophila in male Drosophila melanogaster  

PubMed Central

Background Maintenance and deployment cost of immunity is high, therefore, it is expected to trade-off with other high cost traits like sexual activity. Previous studies with Drosophila melanogaster show that male’s ability to clear bacteria decreases with increase in sexual activity. We subjected this idea to test using two pathogens (Pseudomonas entomophila and Staphylococcus succinus) and three different populations of Drosophila melanogaster. Results We found that sexual activity enhanced male survivorship in a pathogen specific manner. Sexually active males show higher resistance than virgins upon infection with Pseudomonas entomophila. Interestingly, the beneficial effects of sexual activity increased with time of co-habitation with females and declined when access to females was restricted. We observed no change in male survivorship upon experimentally varying the number of sexual interactions. Conclusion Our results show that the sexual activity-immunity trade-off in males cannot be generalised. The trade-off is potentially mediated through complex interactions between the host, pathogen and the environment experienced by the host. PMID:24010544

2013-01-01

235

Molecular characterization of cytoplasmic male sterility conditioned by Gossypium harknessii cytoplasm (CMS-D2) in upland cotton  

Microsoft Academic Search

Cytoplasmic male sterility (CMS) is a maternally inherited trait that fails to produce functional pollen grains. The CMS system\\u000a is widely employed to facilitate the utilization of heterosis in major crops. However, little is known about the CMS associated\\u000a genes in Upland cotton (Gossypium hirsutum). The objective of this study was to compare CMS cotton (CMS-D2) with the cytoplasm from

Jianyong Wu; Yangcang Gong; Minghui Cui; Tingxiang Qi; Liping Guo; Jinfa Zhang; Chaozhu Xing

2011-01-01

236

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

Microsoft Academic Search

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

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

1980-01-01

237

Construction and characterization of a bacterial artificial chromosome library of thermo-sensitive genie male-sterile rice 5460S  

Microsoft Academic Search

In order to develop a detailed physical map of the thermo-sensitive genie male-sterile (TGMS) gene-encompassing region and\\u000a finally clone the TGMS gene, a high-quality rice bacterial artificial chromosome (BAC) library from TGMS rice 5460S was constructed.\\u000a The method of constructing BAC library was examined and optimized. The 5460S library consists of 19 584 BAC clones with an\\u000a average insert size

Fang Qiu; Demin Jin; Jianmin Fu; Chaoliang Zhang; Weiwu Xie; Rencui Yang; Hongbin Zhang; Bin Wang

1999-01-01

238

The Male-Sterility Polymorphism of Silene vulgaris: Analysis of Genetic Data From Two Populations and Comparison With Thymus vulgaris  

Microsoft Academic Search

Results are given of genetic studies of male sterility using plants from two natural populations from Sussex, England. Both populations have substantial frequencies of females, z0.25 in population 1 and 0.60 in population 3. As in the few other gynodioecious populations studied in detail, many genetic factors are present. In population 1, there are at least two, and more likely

D. Charlesworth; Valerie Laporte

239

Exposure to odors of rivals enhances sexual motivation in male giant pandas.  

PubMed

Males will alter their mating behavior to cope with the presence of their competitors. Even exposure to odors from potential competitors can greatly increase male ejaculate expenditure in a variety of animals including insects, fishes, birds and rodents. Major efforts have been made to examine males' plastic responses to sperm competition and its fitness benefits. However, the effects of competitor absence on male's sexual motivation and behaviors remain unclear, which has been proposed to be one of the causes for the poor sexual performance of some captive mammals. This study revealed that sexual motivation can be greatly enhanced in captive male giant pandas (Ailuropoda melanoleuca) by exposure to chemosensory cues from either one or three conspecifics males. It had been shown that potential rivals' odors increased males' chemosensory investigation behavior, as well as their observing, following and sniffing behaviors towards estrous females. Behaviors changed regardless of the number of rivals (one or three). Our results demonstrate the effects of potential competition on male giant pandas' sexual motivation and behavioral coping strategy. We anticipate that our research will provide a fresh insight into the mechanisms underlying poor sexual performance in male captive mammals, and valuable information for the practical management and ex situ conservation of endangered species. PMID:23940532

Bian, Xiaoxing; Liu, Dingzhen; Zeng, Hua; Zhang, Guiquan; Wei, Rongping; Hou, Rong

2013-01-01

240

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

PubMed Central

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

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

241

Characterization of Raphanus sativus Pentatricopeptide Repeat Proteins Encoded by the Fertility Restorer Locus for Ogura Cytoplasmic Male Sterility[W  

PubMed Central

Cytoplasmic male sterility is a maternally inherited trait in higher plants that prevents the production of functional pollen. Ogura cytoplasmic male sterility in radish (Raphanus sativus) is regulated by the orf138 mitochondrial locus. Male fertility can be restored when orf138 accumulation is suppressed by the nuclear Rfo locus, which consists of three genes putatively encoding highly similar pentatricopeptide repeat proteins (PPR-A, -B, and -C). We produced transgenic rapeseed (Brassica napus) plants separately expressing PPR-A and PPR-B and demonstrated that both encoded proteins accumulated preferentially in the anthers of young flower buds. Immunodetection of ORF138 showed that, unlike PPR-B, PPR-A had no effect on the synthesis of the sterility protein. Moreover, immunolocalization experiments indicated that complete elimination of ORF138 from the tapetum of anthers correlated with the restoration of fertility. Thus, the primary role of PPR-B in restoring fertility is to inhibit ORF138 synthesis in the tapetum of young anthers. In situ hybridization experiments confirmed, at the cellular level, that PPR-B has no effect on the accumulation of orf138 mRNA. Lastly, immunoprecipitation experiments demonstrated that PPR-B, but not PPR-A, is associated with the orf138 RNA in vivo, linking restoration activity with the ability to directly or indirectly interact with the orf138 RNA. Together, our data support a role for PPR-B in the translational regulation of orf138 mRNA. PMID:19098270

Uyttewaal, M.; Arnal, N.; Quadrado, M.; Martin-Canadell, A.; Vrielynck, N.; Hiard, S.; Gherbi, H.; Bendahmane, A.; Budar, F.; Mireau, H.

2008-01-01

242

Beta-blocker effects on sexual function in normal males  

Microsoft Academic Search

Among the antihypertensives currently in use, the sympatholytic drugs (e.g., central alpha-agonists, beta-blockers) and diuretics are most commonly associated with sexual side effects. Previous reports of sexual dysfunction associated with these drugs have been based entirely on retrospective and selfreport data. This is the first study to date to investigate beta-blocker effects on sexual function by means of physiological (NPT),

Raymond C. Rosen; John B. Kostis; Albert W. Jekelis

1988-01-01

243

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...

244

CHARACTERIZATION OF THE PERIOD OF SENSITIVITY OF FETAL MALE SEXUAL DEVELOPMENT TO VINCLOZOLIN  

EPA Science Inventory

Characterization of the period of sensitivity of fetal male sexual development to vinclozolin. Wolf CJ, LeBlanc GA, Ostby JS, Gray LE Jr. Endocrinology Branch, MD 72, Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, U....

245

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

E-print Network

Sexual isolation between Drosophila melanogaster females and Drosophila simulans males. I, mating success, sexual maturity, Drosophila melanogaster, Droso- phila simulans. Résumé Isolement sexuel entre femelles Drosophila melanogaster et mâles Drosophila simulans : . relation entre réussites d

Paris-Sud XI, Université de

246

Gender Differences in Experiences of Sexual Harassment: Data from a Male-Dominated Environment  

ERIC Educational Resources Information Center

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…

Street, Amy E.; Gradus, Jaimie L.; Stafford, Jane; Kelly, Kacie

2007-01-01

247

Sexual Encounters: Gay Male College Students' Use of the Internet and Social Media  

ERIC Educational Resources Information Center

There have been many studies that focus on understanding various aspects of human sexuality and how it relates to college students. However, the current research focuses on heterosexual students, leaving a void in the research that focuses on gay male college students. Even more crucially, there is a void in research that focuses on the sexual

Reddick, Rinardo Lamon

2012-01-01

248

Sansei Male Personhood, Corporate Sexuality and Ms. Madeline Girbaud: An Essay in the Hermeneutics of Management.  

ERIC Educational Resources Information Center

Explores the relationship among the self-image of third-generation Japanese-American males, sexual dynamics within corporations, and their managerial behavior. Argues that ethnic and sexual stereotypes influence Japanese-American participation in the management of U.S. corporations, and that membership in "corporate communities" has become a goal…

Tanaka, Ronald

1989-01-01

249

Linkage between sexual orientation and chromosome Xq28 in males but not in females  

Microsoft Academic Search

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

Stella Hu; Angela M. L. Pattatucci; Chavis Patterson; Lin Li; David W. Fulker; Stacey S. Cherny; Leonid Kruglyak; Dean H. Hamer

1995-01-01

250

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

ERIC Educational Resources Information Center

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…

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

2005-01-01

251

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

PubMed Central

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

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

2013-01-01

252

Child Support Enforcement and Sexual Activity of Male Adolescents  

ERIC Educational Resources Information Center

Strong child support enforcement requires fathers to take financial responsibility for their children and may also encourage more responsible sexual behavior. Using the 1997-2001 waves of the 1997 National Longitudinal Survey of Youth (N = 4,272), this article examines the association between child support enforcement and the sexual activity of…

Huang, Chien-Chung; Han, Wen-Jui

2007-01-01

253

Male sexual dysfunction and HIV--a clinical perspective.  

PubMed

Sexual dysfunction in men with HIV is often overlooked by clinicians owing to many factors, including the taboo of sexuality. The improved life expectancy of patients with HIV requires physicians to consider their general wellbeing and sexual health with a renewed interest. However, data on sexual dysfunction in those with HIV are scarce. Erectile dysfunction (ED) is the most common sexual dysfunction in men, with a prevalence of ?30-50% and is frequent even in men <40 years of age. HIV infection itself is the strongest predictor of ED, and many factors related to the infection-fear of virus transmission, changes in body image, HIV-related comorbidities, infection stigma, obligatory condom use-all impair erectile function. The diagnosis and treatment of sexual dysfunction is based on a multidisciplinary approach, which involves specialists in both infectious diseases and sexual medicine. Particular attention should be paid to the promotion of safer sex in these patients. This Review, describes the issues surrounding sexual dysfunction in men with HIV and aims to provide clinical advice for the physician treating these patients. PMID:24394405

Santi, Daniele; Brigante, Giulia; Zona, Stefano; Guaraldi, Giovanni; Rochira, Vincenzo

2014-02-01

254

Stoichiometric shifts in the common bean mitochondrial genome leading to male sterility and spontaneous reversion to fertility  

PubMed Central

The plant mitochondrial genome is characterized by a complex, multipartite structure. In cytoplasmic male-sterile (CMS) common bean, the sterility-inducing mitochondrial configuration maps as three autonomous DNA molecules, one containing the sterility-associated sequence pvs-or f 239. We constructed a physical map of the mitochondrial genome from the direct progenitors to the CMS cytoplasm and have shown that it maps as a single, circular master configuration. With long-exposure autoradiography of DNA gel blots and polymerase chain reaction analysis, we demonstrate that the three-molecule CMS-associated configuration was present at unusually low copy number within the progenitor genome and that the progenitor form was present substoichiometrically within the genome of the CMS line. Furthermore, upon spontaneous reversion to fertility, the progenitor genomic configuration as well as the molecule containing the pvs-or f 239 sterility-associated sequence were both maintained at substoichiometric levels within the revertant genome. In vitro mitochondrial incubation results demonstrated that the genomic shift of the pvs-or f 239-containing molecule to substoichiometric levels upon spontaneous reversion was a reversible phenomenon. Moreover, we demonstrate that substoichiometric forms, apparently silent with regard to gene expression, are transcriptionally and translationally active once amplified. Thus, copy number suppression may serve as an effective means of regulating gene expression in plant mitochondria. PMID:9668135

Janska, H; Sarria, R; Woloszynska, M; Arrieta-Montiel, M; Mackenzie, SA

1998-01-01

255

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

PubMed

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

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

2014-12-01

256

Can Ayahuasca and sleep loss change sexual performance in male rats?  

PubMed

The ingestion of the beverage Ayahuasca usually occurs in religious ceremonies that are performed during the night leading to sleep deprivation. The purpose of the present study was to characterize the acute effects of Ayahuasca upon the sexual response of sleep deprived male rats. One group of sexually experienced male Wistar rats were submitted to a paradoxical sleep deprivation (PSD) protocol for 96h, while another group spent the same amount of time in the home cage (CTRL). After this period, either saline or Ayahuasca drink (250, 500 and 1000?gmL(-1)) was administered by gavage and sexual behavior and hormonal concentrations were measured. Ayahuasca alone significantly decreased sexual performance at all doses. However, in sleep deprived rats, the lower dose increased sexual performance while the intermediate dose produced a detrimental effect on sexual response compared to the CTRL rats at the same dose. Regarding the hormonal analyses, a lower testosterone concentration was observed in sleep-deprived saline rats in relation to the CTRL group. Progesterone was significantly lower only in PSD rats at the dose 500?gmL(-1) compared with CTRL-500?gmL(-1) group. Corticosterone was unchanged among the groups evaluated. Our results suggest that Ayahuasca intake markedly impaired sexual performance alone, but, when combined with sleep deprivation, had significant, but heterogeneous, effects on male sexual response. PMID:25256159

Alvarenga, T A; Polesel, D N; Matos, G; Garcia, V A; Costa, J L; Tufik, S; Andersen, M L

2014-10-01

257

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

PubMed

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. PMID:25287270

Huysamen, Monique; Boonzaier, Floretta

2014-10-01

258

Mechanisms of sexual selection: Sexual swellings and estrogen concentrations as fertility indicators and cues for male consort  

E-print Network

indicators and cues for male consort decisions in wild baboons Laurence R. Gesquiere a,, Emmanuel O. Wango c of baboons (Papio cynocephalus) to test the hypotheses that sexual swellings are reliable indicators of (1 steroids; Estrogen; Baboons; Papio Introduction Both pre- and post-copulatory mate guarding are widespread

Alberts, Susan C

259

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

Microsoft Academic Search

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

William G. Eberhard; Carlos Cordero

1995-01-01

260

Female preference for apparently symmetrical male sexual ornaments in the barn swallow Hirundo rustica  

Microsoft Academic Search

Summary The outermost tail feathers of barn swallows Hirundo rustica apparently reliably signal the quality of males, because individuals with the longest tails have the lowest degree of fluctuating asymmetry (random deviations from symmetry in the otherwise symmetrical tail trait) despite the size of their secondary sexual character. I experimentally tested whether females preferred males with symmetrical tails without altering

Anders Pape Møller

1993-01-01

261

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

Microsoft Academic Search

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

William L. Yarber; Bernadette Yee

1983-01-01

262

Characterization of male killer whale ( Orcinus orca) sexual maturation and reproductive seasonality  

Microsoft Academic Search

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

T. R. Robeck; S. L. Monfort

2006-01-01

263

Vomeronasal Organ: Critical Role in Mediating Sexual Behavior of the Male Hamster  

Microsoft Academic Search

Sexual behavior in male hamsters is totally abolished by bilateral removal of the olfactory bulbs. This operation eliminates sensory input from both the olfactory and the vomeronasal systems. We previously demonstrated that peripheral destruction of the olfactory receptors caused anosmia but did not impair male hamster mating behavior. Here we demonstrate that peripheral deafferentation of the vomeronasal system produces severe

J. Bradley Powers; Sarah S. Winans

1975-01-01

264

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

ERIC Educational Resources Information Center

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.…

Reid, Leonard N.; And Others

265

Intraspecific Communication Through Chemical Signals in Female Mice: Reinforcing Properties of Involatile Male Sexual Pheromones  

Microsoft Academic Search

In rodents, social and reproductive behaviors critically depend on chemical signals, including sexual pheromones that have been suggested (but not demonstrated) to be rewarding. In this work, we analyze this issue by studying the chemoinvestigatory behavior of adult female mice (without experience with male-derived chemicals) toward 1) the synthetic odorant citralva, 2) bedding soiled by different conspecifics (females, males, and

Joana Martinez-Ricos; Carmen Agustin-Pavon; Enrique Lanuza; F. Martinez-Garcia

2006-01-01

266

Exploring Taboos: Comparing Male- and Female-Perpetrated Child Sexual Abuse  

ERIC Educational Resources Information Center

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…

Peter, Tracey

2009-01-01

267

Health Promotion Department Male Advocates for Responsible Sexuality (MARS) Outreach Worker  

E-print Network

Health Promotion Department Male Advocates for Responsible Sexuality (MARS) Outreach Worker General Information MARS Mission: "Men should take a responsible role in promoting equality and cooperation. The person in this position will be responsible for implementing the MARS (Male Advocates for Responsible

Tullos, Desiree

268

Immune activation affects chemical sexual ornaments of male Iberian wall lizards  

NASA Astrophysics Data System (ADS)

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.

López, Pilar; Gabirot, Marianne; Martín, José

2009-01-01

269

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

PubMed Central

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

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

2011-01-01

270

Organization of actin cytoskeleton during meiosis I in a wheat thermo-sensitive genic male sterile line.  

PubMed

BS366 is a thermo-sensitive male sterile line of wheat (Triticum aestivum L.) for two-line hybrid breeding, which exhibits aberrant meiotic cytokinesis under low temperature. Through transcriptome analysis, a possible regulatory role for plant actin cytoskeleton was suggested. However, the organization of actin cytoskeleton in meiosis has been poorly understood so far. Here, fixed microsporocytes during meiosis were labeled with tetramethylrhodamine isothiocyanate-phalloidin and 4',6-diamidino-2-phenylindole. Quantities of fluorescent micrographs were captured using a confocal microscope, including the transient state from metaphase to telophase. We observed that actin filaments were abundant in typical kariokinetic spindle, central spindle (parallel microtubules or actin fibers between two separated chromosomes in anaphase), and phragmoplast. Interestingly, we identified the Chinese lantern-shaped actin phragmoplast in wheat meiosis for the first time. Under low temperature, phragmoplast actin filaments were chaotic and normal cell plate failed to form. These data provide new insights into the organization of actin filaments during male meiosis of plant and support a role of actin cytoskeleton in bringing about thermo-sensitive male sterility in wheat. PMID:22350736

Xu, Chenguang; Liu, Zetao; Zhang, Liping; Zhao, Changping; Yuan, Shaohua; Zhang, Fengting

2013-02-01

271

Adult circumcision and male sexual health: a retrospective analysis.  

PubMed

We aimed to evaluate possible associations of circumcision with several sexual dysfunctions and to identify predictors for the development of these outcomes post-operatively. Telephone surveys about sexual habits and dysfunctions before and after intervention were conducted post-operatively to patients that underwent circumcision in Centro Hospitalar Vila Nova de Gaia/Espinho during 2011. McNemar test was used for a matched-pairs analysis of pre- and post-operative data. Odds ratios, adjusted in a multivariate analysis, explored predictors of de novo sexual dysfunctions after circumcision. With intervention, there was an increase in frequency of erectile dysfunction (9.7% versus 25.8%, P = 0.002) and delayed orgasm (11.3% versus 48.4%, P < 0.001), and a significant symptomatic improvement in patients with pain with intercourse (50.0% versus 6.5%, P < 0.001). Significant predictors for de novo erectile dysfunction were diabetes mellitus (OR 9.81, P = 0.048) and lack of sexual desire (OR 8.76, P = 0.028). Less than three sex partners (OR 7.04, P = 0.007) and low sexual desire (OR 7.49, P = 0.029) were significant predictors for de novo delayed orgasm. PMID:23600924

Dias, J; Freitas, R; Amorim, R; Espiridião, P; Xambre, L; Ferraz, L

2014-06-01

272

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

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…

Huwaidi, Mohamed A.; Daghustani, Wid H.

2013-01-01

273

Male victims of adult sexual assault: a descriptive study of survivors' use of sexual assault treatment services.  

PubMed

This descriptive study aims to provide new information about the services used by sexually assaulted men and adolescent boys presenting to specialized hospital-based sexual assault programs and further insight into the factors that may be associated with their victimization. Information was collected from 38 male clients aged 12+ presenting to 29 sexual assault treatment centers in Ontario, Canada over 12 months. Variables were examined across 6 domains: time to presentation, client sociodemographics, assailant characteristics, assault characteristics, physical health consequences, and service delivery and utilization. A substantial minority of participants reported vulnerabilities such as young age; being Aboriginal; being transgendered, unemployed and/or on disability; working in the sex trade; and living on the streets, in a rehabilitative center, or in a correctional facility. Almost one-third identified or were documented as having a disability and, for most of these victims, it was either psychiatric in nature or developmental delay. All participants accepted at least one service offered; 86% used five or more services, most commonly those related to health care on-site such as crisis counseling, treatment of injuries, and referral for follow-up care for supportive counseling, injury redocumentation, and testing for sexually transmitted infections. These findings reveal that male clients' uptake of specialized sexual assault services is significant and it is, therefore, important to provide access to a comprehensive range of psychological, medical, and forensic treatment options and referrals to other community services for ongoing support. Implications for future research and practice are discussed. PMID:23677965

Du Mont, Janice; Macdonald, Sheila; White, Meghan; Turner, Linda

2013-09-01

274

Male satin bowerbirds ( Ptilonorhynchus violaceus ) compensate for sexual signal loss by enhancing multiple display features  

Microsoft Academic Search

Numerous studies have focussed on the relationship between female choice and the multiple exaggerated sexual traits of males.\\u000a However, little is known about the ability of males to actively enhance specific components of their display in response to\\u000a the loss of one component. We investigated the capacity of male satin bowerbirds (Ptilonorhynchus violaceus) to respond to the loss of one

Benjamin D. Bravery; Anne W. Goldizen

2007-01-01

275

Male sexual signaling is defective in mutants of the apterous gene of Drosophila melanogaster  

Microsoft Academic Search

Theapterous (ap) gene ofDrosophila melanogaster exhibits extreme pleiotrophy: its functioning is essential for life, normal wing structure, juvenile hormone production, female fertility, and normal development of female sexual receptivity. Four mutantap alleles (ap4,ap56f,apc, andapblt) were characterized for three additional phenotypes: male mating success, courtship behavior, and immature male sex appeal (the ability of males to stimulate homosexual cortship). Mating success

John Ringo; Ruth Werczberger; Daniel Segal

1992-01-01

276

The design of complex sexual traits in male barn swallows: associations between signal attributes.  

PubMed

Variation in the expression of sexually selected traits among individuals is widely investigated on the premise that these traits evolved to signal male quality. Significant repeatabilities of sexual signals and their associations with condition, mating success, survivorship and age may be the signatures of sexual selection. However, little is known about the relationship between these sexual attributes. Here we studied 28 acoustic and visual traits in the barn swallow, Hirundo rustica, that may potentially function in sexual selection. Based on effect sizes calculated at the between-individual level, we assessed the relationship between repeatability, condition-dependence, attractiveness, age-dependence and viability indicator value of sexual traits using sexual signals as the units of analyses. Those traits that showed high within-year repeatability also showed high between-year repeatability, indicating that between-individual variation is consistent within and among seasons. In addition, age-dependence of traits, probably causing between-year variation, was negatively related to between-year repeatability. Condition-dependence was negatively correlated with effect sizes for the extent to which traits predicted viability. Therefore, traits that are positively related to immediate condition are those that are negatively related to survival, which may be the signature of a trade-off between current and future reproductive success ultimately reflecting signal reliability. No other significant relationship was found between trait attributes. We conclude that multiple sexual signals reflect different aspects of male quality in the barn swallow. PMID:17040402

Garamszegi, L Z; Hegyi, G; Heylen, D; Ninni, P; de Lope, F; Eens, M; Møller, A P

2006-11-01

277

The role of adrenoceptors in the central nervous system in male and female rat sexual behavior.  

PubMed

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 ?2-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 ?2-adrenoceptors play no major role on any indices of female sexual behavior. PMID:25218984

Snoeren, Eelke M S

2014-09-10

278

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

PubMed

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. PMID:25435106

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

2014-11-27

279

Sexual Dysfunction in Male Subjects Receiving Trifluoperazine, Risperidone, or Olanzapine: Rates Vary With Assessment Questionnaire  

PubMed Central

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

Nebhinani, Naresh; Avasthi, Ajit

2012-01-01

280

A disruption of pachytene DNA metabolism in male mice with chromosomally-derived sterility  

Microsoft Academic Search

DNA metabolism was analyzed in spermatocytes of mice that were sterile either because of X-autosome or autosome-autosome translocations, or because of trisomy. In the strains analyzed, spermatogenic development is arrested by metaphase I or soon thereafter. In all such strains, a disruption of the normal pattern of pachytene DNA metabolism occurred. Prepachytene metabolism appeared normal. Disruption was manifest in both

Y. Hotta; A. C. Chandley; H. Stern; A. G. Searle; C. V. Beechey

1979-01-01

281

The 5' stem-loop and its role in mRNA stability in maize S cytoplasmic male sterility.  

PubMed

The co-transcribed orf355-orf77 region of the mitochondrial genome is associated with S cytoplasmic male sterility (CMS-S) in maize; the amounts of its 1.6- and 2.8-kb transcripts were previously shown to be greatly reduced in fertility-restored microspores relative to the amounts in sterile plants. To investigate the mechanism underlying this reduction, detailed analysis of the 5' and 3' termini of these transcripts was conducted. Using 3' RACE analysis, the polyadenylation sites of the 1.6- and 2.8-kb transcripts were mapped adjacent to a 3' stem-loop, which may play an important role in stabilizing their 3' ends. No difference was found between the polyadenylation sites in sterile and fertility-restored microspores that could account for the differences in orf355-orf77 transcript levels. The 5' terminus of the 1.6-kb transcript was further studied by primer extension; the result revealed that there was a deletion of nine nucleotides only in fertility-restored microspores, and that this deletion eliminated a 5' stem-loop sequence. We propose that the elimination of the 5' stem-loop in the fertility-restored microspores could be the cause of the degradation of the 1.6-kb transcript. Because the 2.8-kb transcript can be cleaved to generate the 1.6-kb transcript, the amount of the 2.8-kb transcript is also reduced in fertility-restored microspores. PMID:16961731

Xiao, Hailin; Zhang, Fangdong; Zheng, Yonglian

2006-09-01

282

Clinical Evaluation of Non-surgical Sterilization of Male Cats with Single Intra-testicular Injection of Calcium Chloride  

PubMed Central

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

2011-01-01

283

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

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

Hudepohl, Adam D.; Parrott, Dominic J.; Zeichner, Amos

2010-01-01

284

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

PubMed

Pornography has become a primary source of sexual education. At the same time, mainstream commercial pornography has coalesced around a relatively homogenous script involving violence and female degradation. Yet, little work has been done exploring the associations between pornography and dyadic sexual encounters: What role does pornography play inside real-world sexual encounters between a man and a woman? Cognitive script theory argues media scripts create a readily accessible heuristic model for decision-making. The more a user watches a particular media script, the more embedded those codes of behavior become in their worldview and the more likely they are to use those scripts to act upon real life experiences. We argue pornography creates a sexual script that then guides sexual experiences. To test this, we surveyed 487 college men (ages 18-29 years) in the United States to compare their rate of pornography use with sexual preferences and concerns. Results showed the more pornography a man watches, the more likely he was to use it during sex, request particular pornographic sex acts of his partner, deliberately conjure images of pornography during sex to maintain arousal, and have concerns over his own sexual performance and body image. Further, higher pornography use was negatively associated with enjoying sexually intimate behaviors with a partner. We conclude that pornography provides a powerful heuristic model which is implicated in men's expectations and behaviors during sexual encounters. PMID:25466233

Sun, Chyng; Bridges, Ana; Johnason, Jennifer; Ezzell, Matt

2014-12-01

285

Sexual experience modulates neuronal activity in male Japanese quail.  

PubMed

After an initial increase, repeated exposure to a particular stimulus or familiarity with an event results in lower immediate early gene expression levels in relevant brain structures. We predicted that similar effects would occur in Japanese quail after repeated sexual experience within brain areas involved in sexual behavior, namely, the medial preoptic nucleus (POM), the bed nucleus of stria terminalis (BST), and the nucleus taeniae of the amygdala (TnA), an avian homolog of medial amygdala. High experience subjects copulated with a female once on each of 16 consecutive days, whereas low experience subjects were allowed to copulate either once or twice. Control subjects were never exposed to a female. High experience subjects were faster to initiate sexual interaction, performed more cloacal contacts, and completed each cloacal contact faster than low experience subjects. Low experience subjects showed an increase in egr-1 (ZENK) expression, an immediate early gene product used as marker of neural activation in birds, in the areas of interest. In contrast, in high experience animals, egr-1 expression in the POM, BST, and the periaqueductal gray (PAG) was not different than the level of expression in unmated controls. These results show that experience modulates the level of immediate early gene expression in the case of sexual behavior. Our results also indicate that immediate early gene expression in specific brain areas is not necessarily related to behavioral output but depends on the behavioral history of the subjects. PMID:17826778

Can, Adem; Domjan, Michael; Delville, Yvon

2007-12-01

286

Application of Orange Oil to PreRelease Holding Boxes Increases the Mating Success of Sterile Males of the Mediterranean Fruit Fly in Field Cage Trials (Diptera: Tephritidae)  

Microsoft Academic Search

Previous research showed that exposure to the aroma of orange oil (Citrus sinensis L.) increased the mating success of male Mediterranean fruit flies (medfly), Ceratitis capitata (Wiedemann). This work, however, involved the exposure of small groups of males (n = 25) in small containers (volume 400 ml). In implementing the Sterile Insect Technique (SIT), several programs use plastic adult rearing

Todd E. Shelly; Elaine Pahio

287

Additional Tests on the Efficacy of Ginger Root Oil in Enhancing the Mating Competitiveness of Sterile Males of the Mediterranean Fruit Fly, Ceratitis capitata (Diptera: Tephritidae)  

Microsoft Academic Search

4 USDA-ARS, 2727 Woodlawn Drive, Honolulu, HI 96822. Abstract. Recent studies have shown that exposure to the aroma of ginger root oil (Zingiber officinale Roscoe; termed GRO hereafter) increases the mating competitive- ness of males of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann). This result suggests that pre-release exposure of sterile males to GRO might increase the effectiveness of

Todd E. Shelly; Ernie Steiner; Vanessa Bosco; Donald McInnis

288

Male fertility and sexual function after spinal cord injury.  

PubMed

Spinal cord injury has an enormous impact upon the sexual relationship of a man and his partner. Erection may be partial or absent, orgasm altered or impossible, and fertility severely impaired. New understanding of the physiology of sexual function and improved treatment can enable most cord-injured men to achieve erections suitable for sexual satisfaction. Modern methods of sperm collection and fertility treatment mean that many can also be fathers. The best results are obtained by a team approach involving rehabilitation and reproductive medicine clinicians, nurses, spinal cord injury specialists and counselors with the cord-injured man and his partner. Erections can be achieved by drugs, such as sildenafil, that block phosphodiesterase 5, prolonging the action of nitric oxide with resultant smooth muscle relaxation. Intracavernosal prostaglandin E1 and mechanical systems, such as vacuum pumps and constriction rings, are also effective. Sexual gratification can be promoted in the context of an understanding relationship in which the cord-injured person can gain pleasure from pleasing his partner and also from his partner's exploration of erotogenic areas not affected by the spinal cord injury. An emphasis on the broader view of sexuality in relationships allows for a continuance and strengthening of bonds between the couple. Vibration ejaculation or electroejaculation can be used to collect semen. For a limited period in the acute phase, usually for about 6-12 days after injury, normal semen can be obtained by electroejaculation from some cord-injured men. With chronic spinal cord injury the semen is of variable quality. Some patients have necrospermia, which may be improved by regular ejaculation. Others have poor quality semen or spermatogenic disorders and, in this situation, in vitro fertilization techniques must be used to achieve parenthood. Trials of assisted ejaculation help individualize cost-effective management of the infertility. PMID:16198718

Brown, D J; Hill, S T; Baker, H W G

2006-01-01

289

Sexual Differentiation of the Human Brain and Male\\/Female Behaviour  

Microsoft Academic Search

\\u000a Once the differentiation of our sexual organs into male or female is settled, the next thing to be differentiated is the brain.\\u000a The difference in brain structures resulting from the interaction of sex hormones and developing brain cells, is thought to\\u000a be the basis of sex differences in behaviour, in gender identity, in gender roles, in our sexual orientation (hetero-,

Dick F. Swaab

290

Sexual selection, multiple male ornaments, and age- and condition-dependent signaling in the common yellowthroat.  

PubMed

In many animals, sexual selection has resulted in complex signaling systems in which males advertise aspects of their phenotypic or genetic quality through elaborate ornamentation and display behaviors. Different ornaments might convey different information or be directed at different receivers, but they might also be redundant signals of quality that function reliably at different times (ages) or in different contexts. We explored sexual selection and age- and condition-dependent signaling in the common yellowthroat (Geothlypis trichas), a sexually dichromatic warbler with two prominent plumage ornaments--a melanin-based, black facial "mask" and carotenoid-based, UV-yellow "bib." In a three-year study, variance among males in the number of social (M(w)) and extra-pair (M(e)) mates generated strong sexual selection on mask and bib attributes. Some traits (mask size, bib yellow brightness) were correlated with male age and did not experience selection beyond age-related increases in M(w) and M(e). Other traits showed age-specific (bib size) or age-reversed (ultraviolet brightness) patterns of selection that paralleled changes in the information-content of each ornament. The components of male fitness generating selection in young versus old males were distinct, reflecting different sources of variation in male fertilization success. Age- and context-dependent changes in the strength, direction, and target of selection may help explain the maintenance of multiple ornaments in this and other species. PMID:19863585

Freeman-Gallant, Corey R; Taff, Conor C; Morin, Douglas F; Dunn, Peter O; Whittingham, Linda A; Tsang, Susan M

2010-04-01

291

Male-Specific Fruitless Isoforms Target Neurodevelopmental Genes to Specify a Sexually Dimorphic Nervous System  

PubMed Central

Summary Background In Drosophila, male courtship behavior is regulated in large part by the gene fruitless (fru). fru encodes a set of putative transcription factors that promote male sexual behavior by controlling the development of sexually dimorphic neuronal circuitry. Little is known about how Fru proteins function at the level of transcriptional regulation or the role that isoform diversity plays in the formation of a male-specific nervous system. Results To characterize the roles of sex-specific Fru isoforms in specifying male behavior, we generated novel isoform-specific mutants and used a genomic approach to identify direct Fru isoform targets during development. We demonstrate that all Fru isoforms directly target genes involved in the development of the nervous system, with individual isoforms exhibiting unique binding specificities. We observe that fru behavioral phenotypes are specified by either a single isoform or a combination of isoforms. Finally, we illustrate the utility of these data for the identification of novel sexually dimorphic genomic enhancers and novel downstream regulators of male sexual behavior. Conclusions These findings suggest that Fru isoform diversity facilitates both redundancy and specificity in gene expression, and that the regulation of neuronal developmental genes may be the most ancient and conserved role of fru in the specification of a male-specific nervous system. PMID:24440396

Neville, Megan C.; Nojima, Tetsuya; Ashley, Elizabeth; Parker, Darren J.; Walker, John; Southall, Tony; Van de Sande, Bram; Marques, Ana C.; Fischer, Bettina; Brand, Andrea H.; Russell, Steven; Ritchie, Michael G.; Aerts, Stein; Goodwin, Stephen F.

2014-01-01

292

Childhood Sexual Abuse in Males and Subsequent Risky Sexual Behavior: A Potential Alcohol-Use Pathway  

ERIC Educational Resources Information Center

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…

Schraufnagel, Trevor J.; Davis, Kelly Cue; George, William H.; Norris, Jeanette

2010-01-01

293

Genetic biases for showy males: Are some genetic systems especially conducive to sexual selection?  

PubMed Central

Male secondary sexual characters (conspicuous ornaments, signals, colors) are among nature's most striking features. Yet, it is unclear why certain groups of organisms are more likely than others to evolve these traits. One explanation for such taxonomic biases is that some genetic systems may be especially conducive to sexual selection. Here, we present theory and simulation results demonstrating that rare alleles encoding either male ornaments or female preferences for those ornaments are better protected against random loss in species with ZZ/ZW or ZZ/ZO sex chromosome systems (male homogamety) than in species with XX/XY or XX/XO systems (male heterogamety). Moreover, this protection is much stronger in diploid than haplodiploid species. We also present empirical data showing that male secondary sexual characters are better developed in diploid than haplodiploid species and in diploid species with male homogamety than in those with male heterogamety. Thus, taxonomic biases for showy males may stem from differences in sex chromosome systems. PMID:12540829

Reeve, Hudson Kern; Pfennig, David W.

2003-01-01

294

High Fetal Estrogen Concentrations: Correlation with Increased Adult Sexual Activity and Decreased Aggression in Male Mice  

NASA Astrophysics Data System (ADS)

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.

Vom Saal, Frederick S.; Grant, William M.; McMullen, Carol W.; Laves, Kurt S.

1983-06-01

295

Persistent Sexual Dysfunction and Depression in Finasteride Users for Male Pattern Hair Loss  

PubMed Central

The use of finasteride for the treatment of male pattern hair loss has recently been the focus of media and internet attention for potential irreversible sexual dysfunction and severe depression. The purpose of this study was to perform a critical review of the recent studies reporting prolonged sexual dysfunction and depression with the use of finasteride for the treatment of male pattern hair loss. A literature search was performed using PubMed to review the literature pertaining to any potential adverse effects with the use of finasteride and its treatment of male pattern hair loss. The authors conclude that the reports of potential irreversible sexual dysfunction and severe depression do raise concerns about the safety of finasteride; however, these studies are wrought with significant bias. Therefore, larger, randomized, double blind, controlled trials are warranted to further ascertain the true potential risks or confirm long-term safety profile of finasteride use. PMID:25584139

Avram, Marc

2014-01-01

296

Women's Beliefs about Male Circumcision, HIV Prevention, and Sexual Behaviors in Kisumu, Kenya  

PubMed Central

It is important to understand how women's sexual practices may be influenced by male circumcision (MC) as an HIV prevention effort. Women's beliefs about MC and sexual behaviour will likely influence the scale-up and uptake of medical MC. We conducted qualitative interviews with 30 sexually active women in Kisumu, Kenya. Women discussed MC related to perceived health benefits, condom use, sexual behaviour, knowledge of susceptibility to HIV and sexually transmitted infections (STIs), circumcision preference, and influence on circumcision uptake. Respondents had a good understanding of the partial protection of MC for acquisition of HIV for men. Women perceived circumcised men as cleaner, carrying fewer diseases, and taking more time to reach ejaculation. Male's circumcision status is a salient factor for women's sexual decision making, including partner choice, and condom use. It will be important that educational information affirms that MC provides only partial protection against female to male transmission of HIV and some STIs; that other HIV and STI prevention methods such as condoms need to be used in conjunction with MC; that MC does not preclude a man from having HIV; and that couples should develop plans for not having sex while the man is healing. PMID:24844845

Riess, Thomas H.; Achieng', Maryline M.; Bailey, Robert C.

2014-01-01

297

Women's beliefs about male circumcision, HIV prevention, and sexual behaviors in Kisumu, Kenya.  

PubMed

It is important to understand how women's sexual practices may be influenced by male circumcision (MC) as an HIV prevention effort. Women's beliefs about MC and sexual behaviour will likely influence the scale-up and uptake of medical MC. We conducted qualitative interviews with 30 sexually active women in Kisumu, Kenya. Women discussed MC related to perceived health benefits, condom use, sexual behaviour, knowledge of susceptibility to HIV and sexually transmitted infections (STIs), circumcision preference, and influence on circumcision uptake. Respondents had a good understanding of the partial protection of MC for acquisition of HIV for men. Women perceived circumcised men as cleaner, carrying fewer diseases, and taking more time to reach ejaculation. Male's circumcision status is a salient factor for women's sexual decision making, including partner choice, and condom use. It will be important that educational information affirms that MC provides only partial protection against female to male transmission of HIV and some STIs; that other HIV and STI prevention methods such as condoms need to be used in conjunction with MC; that MC does not preclude a man from having HIV; and that couples should develop plans for not having sex while the man is healing. PMID:24844845

Riess, Thomas H; Achieng', Maryline M; Bailey, Robert C

2014-01-01

298

Nutritional correlates and mate acquisition role of multiple sexual traits in male collared flycatchers  

NASA Astrophysics Data System (ADS)

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.

Hegyi, Gergely; Szöll?si, Eszter; Jenni-Eiermann, Susanne; Török, János; Eens, Marcel; Garamszegi, László Zsolt

2010-06-01

299

Varieties of male-sexual-identity development in clinical practice: a neuropsychoanalytic model.  

PubMed

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

Stortelder, Frans

2014-01-01

300

Varieties of male-sexual-identity development in clinical practice: a neuropsychoanalytic model  

PubMed Central

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

Stortelder, Frans

2014-01-01

301

Cytological characterization and allelism testing of anther developmental mutants identified in a screen of maize male sterile lines.  

PubMed

Proper regulation of anther differentiation is crucial for producing functional pollen, and defects in or absence of any anther cell type result in male sterility. To deepen understanding of processes required to establish premeiotic cell fate and differentiation of somatic support cell layers a cytological screen of maize male-sterile mutants has been conducted which yielded 42 new mutants including 22 mutants with premeiotic cytological defects (increasing this class fivefold), 7 mutants with postmeiotic defects, and 13 mutants with irregular meiosis. Allelism tests with known and new mutants confirmed new alleles of four premeiotic developmental mutants, including two novel alleles of msca1 and single new alleles of ms32, ms8, and ocl4, and two alleles of the postmeiotic ms45. An allelic pair of newly described mutants was found. Premeiotic mutants are now classified into four categories: anther identity defects, abnormal anther structure, locular wall defects and premature degradation of cell layers, and/or microsporocyte collapse. The range of mutant phenotypic classes is discussed in comparison with developmental genetic investigation of anther development in rice and Arabidopsis to highlight similarities and differences between grasses and eudicots and within the grasses. PMID:23390600

Timofejeva, Ljudmilla; Skibbe, David S; Lee, Sidae; Golubovskaya, Inna; Wang, Rachel; Harper, Lisa; Walbot, Virginia; Cande, William Zacheus

2013-02-01

302

T-URF 13 Protein from Mitochondria of Texas Male-Sterile Maize (Zea mays L.) 1  

PubMed Central

The protein T-URF13 (URF13) is specific to mitochondria of maize (Zea mays L.) with Texas (T) male-sterile cytoplasm and has been implicated in causing male sterility and susceptibility to T-cytoplasm-specific fungal diseases. T-URF13 was purified from isolated mitochondria from maize (line B73) with T cytoplasm by gel filtration and a quasi two-dimensional polyacrylamide gel electrophoresis system. Antibodies to the purified and denatured protein were produced in rabbits. Anti-T-URF13 antiserum was used to show that T-URF13 is in the inner membrane of mitochondria and behaves as an integral membrane protein when mitochondria are fractionated with sodium carbonate or Triton X-114. The antiserum and protein A tagged with 20-nanometer-gold particles were used to localize T-URF13 in T mitochondria by electron microscopy of sections of isolated mitochondria from etiolated shoots and sections of roots and of tapetal cells at pre-and post-degeneration stages of microsporogenesis. The microscopic study confirms that T-URF13 is specifically localized in the mitochondrial membranes of all of the T mitochondria tested, notably those in the tapetum from the meiocyte stage to the late-microspore stage. No change in the amount of labeled T-URF13 protein in the mitochondria of aging tapetal cells was detected. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:16668065

Hack, Ethan; Lin, Chentao; Yang, Hongyun; Horner, Harry T.

1991-01-01

303

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

PubMed Central

Jasmonic acid (JA) and its precursor 12-oxophytodienoic acid (OPDA) act as plant growth regulators and mediate responses to environmental cues. To investigate the role of these oxylipins in anther and pollen development, we characterized a T-DNA-tagged, male-sterile mutant of Arabidopsis, opr3. The opr3 mutant plants are sterile but can be rendered fertile by exogenous JA but not by OPDA. Cloning of the mutant locus indicates that it encodes an isozyme of 12-oxophytodienoate reductase, designated OPR3. All of the defects in opr3 are alleviated by transformation of the mutant with an OPR3 cDNA. Our results indicate that JA and not OPDA is the signaling molecule that induces and coordinates the elongation of the anther filament, the opening of the stomium at anthesis, and the production of viable pollen. Just as importantly, our data demonstrate that OPR3 is the only isoform of OPR capable of reducing the correct stereoisomer of OPDA to produce JA required for male gametophyte development. PMID:10973494

Stintzi, Annick; Browse, John

2000-01-01

304

Experimental evolution exposes female and male responses to sexual selection and conflict in Tribolium castaneum.  

PubMed

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. PMID:21091981

Michalczyk, ?ukasz; Millard, Anna L; Martin, Oliver Y; Lumley, Alyson J; Emerson, Brent C; Gage, Matthew J G

2011-03-01

305

Early sexual maturity in male hamadryas baboons (Papio hamadryas hamadryas) and its reproductive implications.  

PubMed

We present data on sexual maturity in young hamadryas baboon males (Papio hamadryas hamadryas) and its reproductive consequences in a large captive baboon colony. Hamadryas baboons live in a multilevel social system, with one-male units (OMUs) as the smallest social entity. Male leaders of OMUs are believed to monopolize matings within their OMUs; hence mating is believed to be polygynous and monandrous. In a captive colony of hamadryas baboons, we found evidence that young males less than 4 years old fathered at least 2.5% of 121 offspring born subsequent to vasectomy of all adult males, and males aged 4-5 years fathered at least 16.5% of the offspring. Additional evidence that these young males are able to sire offspring came from a morphological comparison of sperm from hamadryas males of different ages. The sperm of a 48-month-old hamadryas baboon were morphologically indistinguishable from viable sperm from adult males, whereas sperm from a 45-month-old male showed some aberrations. If successful copulations by adolescent males constitute a regular pattern even in free-ranging hamadryas baboons, a hamadryas male's chances to reproduce would not be limited to his role as an OMU leader as previously assumed, and a male's reproductive career would consist of two phases: the adolescent phase, and the OMU leader male phase. PMID:16331661

Zinner, Dietmar; Krebs, Ellen; Schrod, Annette; Kaumanns, Werner

2006-04-01

306

Characterization of male killer whale (Orcinus orca) sexual maturation and reproductive seasonality.  

PubMed

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. PMID:16325249

Robeck, T R; Monfort, S L

2006-07-15

307

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

PubMed

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 condom with their regular partner. Future research should further examine how gender shapes sexual risk activities in both commercial and non-commercial relationships. PMID:22304493

Katsulis, Yasmina; Durfee, Alesha

2012-01-01

308

Is sexual ornamentation an honest signal of male quality in the Chinese grouse (Tetrastes sewerzowi)?  

PubMed

We examined the variation in sexual ornamentation of male Chinese grouse (Tetrastes sewerzowi) in the Gansu Province, China, seeking to identify factors involved in whether ornament size and brightness are honest signals of male quality. Compared to unmated males, mated males had significantly larger and redder combs and, although they did not have significantly larger territories, they defended them more vigorously. Mated males had significantly higher blood carotenoid and testosterone levels, significantly better body condition, and significantly lower parasite loads than unmated males. Our findings are thus consistent with the hypothesis that comb size and color are honest signals of better male quality in the grouse, mediated through lower parasite loads and/or higher testosterone levels. PMID:24386132

Yang, Chen; Wang, Jie; Fang, Yun; Sun, Yue-Hua

2013-01-01

309

Exploring the Overlap in Male Juvenile Sexual Offending and General Delinquency: Trauma, Alcohol Use, and Masculine Beliefs  

ERIC Educational Resources Information Center

Despite Burton and Meezan's (2004) finding that sexually aggressive youth are three to four times more likely to recidivate nonsexually than sexually, there is little to no research to date that explores this overlap in criminality. With a sample of 290 male sexually violent adjudicated and incarcerated youth, this study was able to successfully…

Brown, Adam; Burton, David L.

2010-01-01

310

An Initial Validation of a Measure of Personal and Social Perceptions of the Sexual Abuse of Males  

ERIC Educational Resources Information Center

Objective/Method: The Sexual Abuse of Males Perceptions Scale (SAMPS) is a measure designed to assess an individual's personal and projected social perceptions of myths about the sexual abuse of boys and men. Myths are rigid, stereotypical beliefs that invalidate the experiences and minimize the profound effects of sexual abuse on boys and men.…

Nalavany, Blace A.; Abell, Neil

2004-01-01

311

Sexual selection mediated by the thermoregulatory effects of male colour pattern in the ambush bug Phymata americana  

Microsoft Academic Search

Sexual dimorphism in coloration is a taxonomically widespread phenomenon often attributed to sexual selection on visual signals. However, the ambush bug Phymata americana exhibits sexual dimorphism in coloration that has no apparent signalling function. Here we provide evidence that colour pattern in this species influences male mating success indirectly through its effect on thermoregulation. We demonstrate, using experimental manipulation, that

David Punzalan; F. Helen Rodd; Locke Rowe

2009-01-01

312

Cryptic Sex within Male?Sterile Polyploid Populations of the Easter Daisy, Townsendia hookeri  

Microsoft Academic Search

After a transition from sexuality to asexuality, the evolutionary dynamics in apomictic lineages will largely depend on the frequency of recombination. We evaluated the presence and extent of asexuality and recom- bination within populations of the Easter daisy, Townsendia hookeri, from the Yukon Territory, Canada. Amplified fragment-length polymorphism (AFLP) fingerprints were used to genotype 78 individuals from four populations. Multilocus

Stacey Lee Thompson; Gina Choe; Kermit Ritland; Jeannette Whittony

2008-01-01

313

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

PubMed

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. PMID:19073559

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

2008-11-01

314

Magnetic resonance imaging of male and female genitals during coitus and female sexual arousal  

PubMed Central

Objective To find out whether taking images of the male and female genitals during coitus is feasible and to find out whether former and current ideas about the anatomy during sexual intercourse and during female sexual arousal are based on assumptions or on facts. Design Observational study. Setting University hospital in the Netherlands. Methods Magnetic resonance imaging was used to study the female sexual response and the male and female genitals during coitus. Thirteen experiments were performed with eight couples and three single women. Results The images obtained showed that during intercourse in the “missionary position” the penis has the shape of a boomerang and 1/3 of its length consists of the root of the penis. During female sexual arousal without intercourse the uterus was raised and the anterior vaginal wall lengthened. The size of the uterus did not increase during sexual arousal. Conclusion Taking magnetic resonance images of the male and female genitals during coitus is feasible and contributes to understanding of anatomy. PMID:10600954

Schultz, Willibrord Weijmar; van Andel, Pek; Sabelis, Ida; Mooyaart, Eduard

1999-01-01

315

Sexual selection did not contribute to the evolution of male lifespan under curtailed age at reproduction in a seed beetle  

Microsoft Academic Search

Sexual selection is a powerful evolutionary force that is hypothesised to play an important role in the evolution of lifespan. Here we test for the potential contribution of sexual selection to the rapid evolution of male lifespan in replicated laboratory populations of the seed beetle, Callosobruchus maculatus. 2. For 35 generations, newly hatched virgin male beetles from eight different populations

ALEXEI A. M AKLAKOV; F RICKE

2009-01-01

316

Female mate preferences for male body size and shape promote sexual isolation in threespine sticklebacks  

PubMed Central

Female mate preferences for ecologically relevant traits may enhance natural selection, leading to rapid divergence. They may also forge a link between mate choice within species and sexual isolation between species. Here, we examine female mate preference for two ecologically important traits: body size and body shape. We measured female preferences within and between species of benthic, limnetic, and anadromous threespine sticklebacks (Gasterosteus aculeatus species complex). We found that mate preferences differed between species and between contexts (i.e., within vs. between species). Within species, anadromous females preferred males that were deep bodied for their size, benthic females preferred larger males (as measured by centroid size), and limnetic females preferred males that were more limnetic shaped. In heterospecific mating trials between benthics and limnetics, limnetic females continued to prefer males that were more limnetic like in shape when presented with benthic males. Benthic females showed no preferences for size when presented with limnetic males. These results show that females use ecologically relevant traits to select mates in all three species and that female preference has diverged between species. These results suggest that sexual selection may act in concert with natural selection on stickleback size and shape. Further, our results suggest that female preferences may track adaptation to local environments and contribute to sexual isolation between benthic and limnetic sticklebacks. PMID:23919161

Head, Megan L; Kozak, Genevieve M; Boughman, Janette W

2013-01-01

317

Effects of egg testosterone on female mate choice and male sexual behavior in the pheasant.  

PubMed

Evidence is accumulating that sex steroids in the eggs, besides affecting progeny phenotype and behavior in the short term, also have enduring effects until adulthood, when they may translate into differences in reproductive strategies and success. Maternal steroids transfer may therefore affect both agonistic behavior and mate choice decisions, either through the promotion of body size and condition or through a priming effect on the neuroendocrine system. However, owing to the prevalence of a short-term perspective, relevance of maternal transfer of sex steroids to sexual selection processes has been seldom studied. Here we investigate the effects of an experimental increase in egg testosterone on male dominance and copulation success in the ring-necked pheasant, Phasianus colchicus, a polygynous galliform with multiple male ornamental traits, in captivity. We found that females from testosterone (T) injected eggs copulated less than control females. Males from T-injected eggs obtained more copulations than control males, specifically with control females. The effect of male 'ordinary' and secondary sexual traits on either dominance or copulation frequency did not depend on early exposure to T, nor did T treatment affect male dominance. Present results demonstrate that variation in the early hormonal environment set up by mothers affects sexual behavior of the offspring, which might translate into fitness differences. PMID:21029735

Bonisoli-Alquati, Andrea; Matteo, Angelo; Ambrosini, Roberto; Rubolini, Diego; Romano, Maria; Caprioli, Manuela; Dessì-Fulgheri, Francesco; Baratti, Mariella; Saino, Nicola

2011-01-01

318

Variation in a female sexual attractiveness pheromone controls male mate choice in garter snakes.  

PubMed

Male red-sided garter snakes (Thamnophis sirtalis parietalis) display a courtship preference for larger females during the breeding season. Utilizing behavioral experiments and chemical analyses, we tested the hypothesis that males can discriminate among females of varying size solely by means of the sexual attractiveness pheromone, a previously characterized sex pheromone composed of a homologous series of long-chain saturated and omega-9 cis-unsaturated methyl ketones contained in the skin lipids of females. When presented with skin lipid extracts from large and small females, a greater proportion of males displayed courtship behaviors to large female extracts. This demonstrates that there is an intrinsic property of the female skin lipids that allows males to differentiate among large and small females. Analysis of the sexual attractiveness pheromone revealed that the necessary variation exists for this pheromone to function as a reliable indicator to males of female body size. Specifically, we observed a strong correlation between female snout-vent length and the relative concentration of saturated and omega-9 cis-unsaturated methyl ketones composing the pheromone; smaller females expressed pheromone profiles higher in saturated methyl ketones. while larger females expressed pheromone profiles dominated by unsaturated methyl ketones. The results of this study suggest that male red-sided garter snakes utilize compositional variation in the female sexual attractiveness pheromone to differentiate among potential mates of varying size. PMID:12184402

LeMaster, Michael P; Mason, Robert T

2002-06-01

319

Prevalence of Consensual Male–Male Sex and Sexual Violence, and Associations with HIV in South Africa: A Population-Based Cross-Sectional Study  

PubMed Central

Background In sub-Saharan Africa the population prevalence of men who have sex with men (MSM) is unknown, as is the population prevalence of male-on-male sexual violence, and whether male-on-male sexual violence may relate to HIV risk. This paper describes lifetime prevalence of consensual male–male sexual behavior and male-on-male sexual violence (victimization and perpetration) in two South African provinces, socio-demographic factors associated with these experiences, and associations with HIV serostatus. Methods and Findings In a cross-sectional study conducted in 2008, men aged 18–49 y from randomly selected households in the Eastern Cape and KwaZulu-Natal provinces provided anonymous survey data and dried blood spots for HIV serostatus assessment. Interviews were completed in 1,737 of 2,298 (75.6%) of enumerated and eligible households. From these households, 1,705 men (97.1%) provided data on lifetime history of same-sex experiences, and 1,220 (70.2%) also provided dried blood spots for HIV testing. 5.4% (n?=?92) of participants reported a lifetime history of any consensual sexual activity with another man; 9.6% (n?=?164) reported any sexual victimization by a man, and 3.0% (n?=?51) reported perpetrating sexual violence against another man. 85.0% (n?=?79) of men with a history of consensual sex with men reported having a current female partner, and 27.7% (n?=?26) reported having a current male partner. Of the latter, 80.6% (n?=?21/26) also reported having a female partner. Men reporting a history of consensual male–male sexual behavior are more likely to have been a victim of male-on-male sexual violence (adjusted odds ratio [aOR]?=?7.24; 95% CI 4.26–12.3), and to have perpetrated sexual violence against another man (aOR?=?3.10; 95% CI 1.22–7.90). Men reporting consensual oral/anal sex with a man were more likely to be HIV+ than men with no such history (aOR?=?3.11; 95% CI 1.24–7.80). Men who had raped a man were more likely to be HIV+ than non-perpetrators (aOR?=?3.58; 95% CI 1.17–10.9). Conclusions In this sample, one in 20 men (5.4%) reported lifetime consensual sexual contact with a man, while about one in ten (9.6%) reported experience of male-on-male sexual violence victimization. Men who reported having had sex with men were more likely to be HIV+, as were men who reported perpetrating sexual violence towards other men. Whilst there was no direct measure of male–female concurrency (having overlapping sexual relationships with men and women), the data suggest that this may have been common. These findings suggest that HIV prevention messages regarding male–male sex in South Africa should be mainstreamed with prevention messages for the general population, and sexual health interventions and HIV prevention interventions for South African men should explicitly address male-on-male sexual violence. Please see later in the article for the Editors' Summary PMID:23853554

Dunkle, Kristin L.; Jewkes, Rachel K.; Murdock, Daniel W.; Sikweyiya, Yandisa; Morrell, Robert

2013-01-01

320

The Treatment of Male Sexual Offenders: Countertransference Reactions.  

ERIC Educational Resources Information Center

Addresses the therapist's reactions to clinical work with sex offenders. Focuses on the particular experiences of one case, and discusses the female therapist's responses to the male client that may be the result of other experiences. Explores some reactions and difficulties that professionals may encounter in work with sex offenders. (JPS)

Mitchell, Cynthia; Melikian, Karen

1995-01-01

321

Sexually intrusive behavior among alleged CSA male victims: a prospective study.  

PubMed

Child Sexual Abuse (CSA) is one widely cited risk factor for Sexually Intrusive Behavior (SIB) among boys. To identify variables that moderate the early onset of SIB in a sample of boys, alleged victims of sexual abuse, the current study involved a prospective examination of all investigations of male CSA victims and those of boys aged under 14 who were suspected of committing SIBs on other children in Israel over a 10-year period. Comparing victims with and without SIB records revealed differences on personal and family factors as well as on the characteristics of abuse. A regression model controlling for age and family factors correctly classified over three quarters of the subjects based on reported experiences of abuse. The data help identify characteristics of the abuse that facilitate the early onset of SIB among male victims of CSA. PMID:23698743

Hershkowitz, Irit

2014-06-01

322

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 reproductive developmental abnormalities later in adult life which are associated with declines in fetal testicular testosterone (T) production and insulin-like three hormone (lnsl-3...

323

Objects of Desire: Objectification as a Function of Male Sexual Orientation  

Microsoft Academic Search

This study examined the influence of male sexual orientation on the objectification of self and others. Objectification is a process by which a perceiver adopts a purely externalized view of either the self or another, a process by which a person’s body becomes the main representation of that person’s identity. A sample of 29 heterosexual and 30 gay men was

Megan Kozak; Heidi Frankenhauser; Tomi-Ann Roberts

2009-01-01

324

Sexual coercion in gay male and lesbian relationships: Predictors and implications for support services  

Microsoft Academic Search

Numerous studies have documented the prevalence of forced sex in heterosexual couples. Positive effects of this research include increases in awareness about the problem among helping professionals and the public, as well as increases in support services and prevention programs. However, no research has been done on sexual coercion in gay male and lesbian relationships, and few support services exist.

Caroline K. Waterman; Lori J. Dawson; Michael J. Bologna

1989-01-01

325

The frequency, sources, and correlates of sexual harassment among women in traditional male occupations  

Microsoft Academic Search

Sexual harassment has increasingly come to be recognized as a major problem confronting working women. Utilizing the results of a survey of women in traditional male occupations (N=160), this paper summarizes some new data on the amount, type, and sources of harassment experienced by this group. Interpreting these findings within the content of the larger theory of patriarchy, it also

Edward Lafontaine; Leslie Tredeau

1986-01-01

326

Male gender roles and sexuality: Implications for women's AIDS risk and prevention  

Microsoft Academic Search

The focus of prevention of the heterosexual AIDS epidemic in the U.S. has been on women. The role of men in sexual decision making has not been emphasized in AIDS prevention approaches. As a result, the heterosexual epidemic for women continues unabated because of the lack of attention to the behavior of male sex partners. This article describes a profile

Carole A. Campbell

1995-01-01

327

SEXUAL BEHAVIOR AND AGGRESSION IN MALE MICE: INVOLVEMENT OF THE VOMERONASAL SYSTEM  

Microsoft Academic Search

Recent observations have implicated the vomeronasal (accessory olfactory) system in the chemosensory control of rodent social behaviors. The purpose of this study was to observe the effects of peripheral vomeronasal organ extirpation on sexual behavior, aggression, and urine marking in male mice. Relative to sham-operated control animals, mice lacking vomeronasal organs displayed significantly reduced levels of copulatory behavior and intermale

ANDREW N. CLANCY; ARTHUR COQUELIN; FOTEOS MACRIDES; ROGER A. GORSKI; ERNEST P. NOBLES

328

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

PubMed Central

Background Male clients of female sex workers (FSWs) are at risk of HIV and other sexually transmitted infections (STIs). We conducted a two-arm randomized controlled trial to test the efficacy of a sexual risk reduction intervention for male clients of FSWs in Tijuana, Mexico. Methods/Design Male clients of FSWs who were at least 18, were HIV-negative at baseline, and reported recent unprotected sex with FSWs were randomized to the Hombre Seguro sexual risk reduction intervention, or a time-attention didactic control condition. Each condition lasted approximately one hour. Participants underwent interviewer-administered surveys and testing for HIV and other STIs at baseline, and at 4, 8, and 12 month follow-ups. Combined HIV/STI incidence and unprotected vaginal and anal sex acts with FSWs were the primary outcomes. Discussion A total of 400 participants were randomized to one of the two conditions. Analyses indicated that randomization was successful; there were no significant differences between the participants in the two conditions at baseline. Average follow-up was 84% across both conditions. This is the first study to test the efficacy of a sexual risk reduction intervention for male clients of FSWs using the rigor of a randomized controlled trial. Trial registration NCT01280838, Date of registration: January 19, 2011. PMID:24885949

2014-01-01

329

A Neutral Odor May Become a Sexual Incentive through Classical Conditioning in Male Rats  

ERIC Educational Resources Information Center

A neutral olfactory stimulus was employed as CS in a series of experiments with a sexually receptive female as UCS and the execution of an intromission as the UCR. Each experimental session lasted until the male ejaculated. The time the experimental subject spent in a zone adjacent to the source of the olfactory stimulus during the 10 s of CS…

Kvitvik, Inger-Line; Berg, Kristine Marit; Agmo, Anders

2010-01-01

330

A Study of the Difference between the Likelihood of Males and Females Being Sexually Abused.  

ERIC Educational Resources Information Center

The purpose of this study was to explore the difference between the sexual abuse of males and females. The study group was a caseload of clients from the Northside Family Resource Center in the Houston area, a branch of the Mental Health Mental Retardation Association (MHMRA) of Harris County, Texas. The researcher studied 21 children, age 10…

Calhoun, Yolanda Marie

331

Characterization of a Novel Bile Alcohol Sulfate Released by Sexually Mature Male Sea Lamprey (Petromyzon marinus)  

PubMed Central

A sulphate-conjugated bile alcohol, 3,12-diketo-4,6-petromyzonene-24-sulfate (DKPES), was identified using bioassay-guided fractionation from water conditioned with sexually mature male sea lamprey (Petromyzon marinus). The structure and relative stereochemistry of DKPES was established using spectroscopic data. The electro-olfactogram (EOG) response threshold of DKPES was 10?7 Molar (M) and that of 3-keto petromyzonol sulfate (3 KPZS; a known component of the male sea lamprey sex pheromone) was 10?10 M. Behavioural studies indicated that DKPES can be detected at low concentrations by attracting sexually mature females to nests when combined with 3 KPZS. Nests baited with a mixture of DKPES and 3 KPZS (ratio 1?29.8) attracted equal numbers of sexually mature females compared to an adjacent nest baited with 3 KPZS alone. When DKPES and 3 KPZS mixtures were applied at ratios of 2?29.8 and 10?29.8, the proportion of sexually mature females that entered baited nests increased to 73% and 70%, respectively. None of the sexually mature females released were attracted to nests baited with DKPES alone. These results indicated that DKPES is a component of the sex pheromone released by sexually mature male sea lamprey, and is the second biologically active compound identified from this pheromone. DKPES represents the first example that a minor component of a vertebrate pheromone can be combined with a major component to elicit critical sexual behaviors. DKPES holds considerable promise for increasing the effectiveness of pheromone-baited trapping as a means of sea lamprey control in the Laurentian Great Lakes. PMID:23874530

Li, Ke; Brant, Cory O.; Siefkes, Michael J.; Kruckman, Hanna G.; Li, Weiming

2013-01-01

332

The impact of parenting on gay male couples' relationships, sexuality, and HIV risk  

PubMed Central

Parenthood changes couples' relationships across multiple domains, generally decreasing relationship quality, sexual satisfaction, and sexual frequency. Emerging research suggests that gay couples who are parenting might experience similar challenges. However, such changes might have even more profound implications for gay couples' health, and in particular their HIV risk, given the somewhat different ways in which they negotiate and tolerate sexual behaviors with outside partners. We aimed to examine these issues in a qualitative analysis of interviews from 48 gay male couples who were actively parenting children. Findings suggest that parenthood increases men's commitment to their primary relationship while simultaneously decreasing time and energy for relationship maintenance, and generally decreasing sexual satisfaction. These challenges alone did not generally result in greater infidelity or HIV risk, as most men reported successfully coping with such changes through a combination of acceptance and revaluing what is important in their relationships. Additionally, couples reported negotiating agreements regarding sex with outside partners that closely resemble those documented in studies of gay couples who are not parents. Men reported that parenthood typically decreased their opportunities to engage in sex with outside partners, but also posed barriers to talking about these behaviors with their partners and healthcare providers. HIV-related sexual risk behavior was relatively rare, but nevertheless present in some men. Providers should assess sexual function as a regular part of their work with gay couples who parent, and facilitate opportunities for men to discuss their sexual agreements both with their primary partners and with relevant healthcare providers.

Huebner, David M.; Mandic, Carmen Gómez; Mackaronis, Julia E.; Beougher, Sean C.; Hoff, Colleen C.

2014-01-01

333

Environmentally Realistic Exposure to the Herbicide Atrazine Alters Some Sexually Selected Traits in Male Guppies  

PubMed Central

Male mating signals, including ornaments and courtship displays, and other sexually selected traits, like male-male aggression, are largely controlled by sex hormones. Environmental pollutants, notably endocrine disrupting compounds, can interfere with the proper functioning of hormones, thereby impacting the expression of hormonally regulated traits. Atrazine, one of the most widely used herbicides, can alter sex hormone levels in exposed animals. I tested the effects of environmentally relevant atrazine exposures on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Prolonged atrazine exposure reduced the expression of two honest signals: the area of orange spots (ornaments) and the number of courtship displays performed. Atrazine exposure also reduced aggression towards competing males in the context of mate competition. In the wild, exposure levels vary among individuals because of differential distribution of the pollutants across habitats; hence, differently impacted males often compete for the same mates. Disrupted mating signals can reduce reproductive success as females avoid mating with perceptibly suboptimal males. Less aggressive males are at a competitive disadvantage and lose access to females. This study highlights the effects of atrazine on ecologically relevant mating signals and behaviors in exposed wildlife. Altered reproductive traits have important implications for population dynamics, evolutionary patterns, and conservation of wildlife species. PMID:22312428

Shenoy, Kausalya

2012-01-01

334

Disturbed sexual characteristics in male mosquitofish (Gambusia holbrooki) from a lake contaminated with endocrine disruptors.  

PubMed Central

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 with numerous chemicals, some of which possess endocrine-disrupting activity. Male mosquitofish (Gambusia holbrooki) were collected monthly from December 2000 through May 2001 from Lake Apopka and two nearby reference lakes, Orange Lake and Lake Woodruff National Wildlife Refuge. Selected sexual characteristics were compared temporally and among lakes during the collection period. Male fish from Lake Apopka had slightly shorter gonopodia and on average 32 and 47% fewer sperm cells per milligram testis, when compared with the fish collected from Orange Lake and Lake Woodruff, respectively. The testes weights increased markedly during spring, with significantly smaller testes in fish from Lake Apopka than from Orange Lake, but surprisingly, the smallest testes occurred in males obtained from the Lake Woodruff population. The highest liver weights were found in the Lake Apopka population. Whole-body concentrations of testosterone and estradiol varied among months; the peak testosterone concentration occurred in January and was significantly lower in male fish from Lake Apopka compared with Orange Lake. The intensity of male courtship behavior was highly correlated to body testosterone concentration, but no statistically significant differences in sexual behavior among the lakes were found. We conclude that sexual characteristics of relevance to male reproductive capacity are altered in the Lake Apopka mosquitofish population, and we discuss the presence of chemicals with antiandrogenic effects in Lake Apopka as a possible cause of the observed alterations. PMID:12727596

Toft, Gunnar; Edwards, Thea M; Baatrup, Erik; Guillette, Louis J

2003-01-01

335

[Using single primer PCR to amplify the orf25 gene fragment related to plant male-sterility in Salicornia europaea].  

PubMed

The gene orf25 encodes functional protein that may play an important role in plant fertility control in nature. To clone the orf25 from Salicornia europaea Xinjiang into a T-vector, a single designed primer was used to amplify 1.7kb cDNA fragment with RT-PCR. Sequence analysis reveals that the cloned fragment contains entire orf25 coding region with 98%, 95%, 92% and 88% identity to that of orf25 from Beta vulgaris, Nicotiana, wheat and maize mitochondrion, respectively. This analysis suggests that orf25 gene is highly conserved in terms of evolution in plant; and it also suggests that wild plant Salicornia europaea contain a male-sterility gene similar to crops that is of great importance in improvement of the breed of crop. PMID:15969049

Li, Jin-Yao; Zhang, Fu-Chun; Ma, Ji; Shan, Wen-Juan; Wang, Bin

2003-01-01

336

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

PubMed Central

Background Previous qualitative research has examined male sex workers in the Czech Republic, but this mapping study is the first to investigate male sex work in a quantitative research design and focus on the mental health of these sex workers. This study also examines male sex workers’ mental health problems in relation to their sexual identity or orientation. Material/Methods A sample of Czech male sex workers (N=40) were examined on a range of sexual and psychological variables using a quantitative survey administered face-to-face. The study employed locally validated versions of Beck’s Depression Inventory and Zung’s Self-Report Anxiety Scale. Results The results indicate that for homosexuals, working as a male sex worker is not related to any serious mental health problems. However, those identifying as heterosexual and bisexual more frequently reported symptoms of depression and bisexuals showed significantly more anxiety. Conclusions These findings suggest sexual identity is an important issue to consider when addressing the mental health needs of this population. PMID:25239091

Bar-Johnson, Michael; Weiss, Petr

2014-01-01

337

Sexual selection on cuticular hydrocarbons of male sagebrush crickets in the wild.  

PubMed

Cuticular hydrocarbons (CHCs) play an essential role in mate recognition in insects but the form and intensity of sexual selection on CHCs has only been evaluated in a handful of studies, and never in a natural population. We quantified sexual selection operating on CHCs in a wild population of sagebrush crickets, a species in which nuptial feeding by females imposes an unambiguous phenotypic marker on males. Multivariate selection analysis revealed a saddle-shaped fitness surface, suggesting a complex interplay between the total abundance of CHCs and specific CHC combinations in their influence on female choice. The fitness surface resulting from two axes of disruptive selection reflected a trade-off between short- and long-chained CHCs, suggesting that males may be sacrificing some level of desiccation resistance in favour of increased attractiveness. There was a significant correlation between male body size and total CHC abundance, suggesting that male CHCs provide females with a reliable cue for maximizing benefits obtained from males. Notwithstanding the conspicuousness of males' acoustic signals, our results suggest that selection imposed on males via female mating preferences may be far more complex than previously appreciated and operating in multiple sensory modalities. PMID:24197415

Steiger, Sandra; Ower, Geoffrey D; Stökl, Johannes; Mitchell, Christopher; Hunt, John; Sakaluk, Scott K

2013-12-22

338

What Is So Special About Male Adolescent Sexual Offending? A Review and Test of Explanations Through Meta-Analysis  

Microsoft Academic Search

We tested special and general explanations of male adolescent sexual offending by conducting a meta-analysis of 59 independent studies comparing male adolescent sex offenders (n = 3,855) with male adolescent non-sex offenders (n = 13,393) on theoretically derived variables reflecting general delinquency risk factors (antisocial tendencies), childhood abuse, exposure to violence, family problems, interpersonal problems, sexuality, psychopathology, and cognitive abilities.

Michael C. Seto; Martin L. Lalumière

2010-01-01

339

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

PubMed

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

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

2012-11-01

340

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

SciTech Connect

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 la calidad de las moscas que la irradiacion en atmosferas con proporcion normal de oxigeno. Aunque esta ha sido por mucho tiempo parte del protocolo de irradiacion en plantas de produccion de mosca esteril, hasta ahora no se ha medido el contenido de oxigeno dentro de los recipientes de empaque de pupa durante la irradiacion. El presente estudio investigo los contenidos de O{sub 2} en los contenedores de pupas de la mosca de las frutas del Mediterraneo (Ceratitis capitata Wiedeman), la habilidad de pupas de crear hipoxia dentro de los contenedores, y los efectos del contenido de O{sub 2} durante la irradiacion del contenedor en la calidad y capacidad de apareamiento de moscas esteriles. Pupas de un dia antes de emerger como adultos crearon atmosferas de maxima hipoxia dentro del empaque en aproximadamente una hora. La proporcion de consumo de O{sub 2} en contenedores sellados es dependiente de la edad de la pupa, y de la temperatura de incubacion. La temperatura de incubacion no afecto significativamente la calidad ni la capacidad de apareamiento de machos derivados de pupas irradiadas bajo condiciones de hipoxia. Sin embargo, la capacidad de apareamiento de machos irradiados como pupas en contenedores abiertos y en condiciones oxigenadas fue drasticamente afectada. En comparacion a los resultados anteriores, atmosferas de 2% y 10% O{sub 2} durante la irradiacion no afectaron la capacidad de apareamiento de moscas esteriles. Polvo fluorescente, aplicado a pupas para marcar las moscas esteriles, no tuvo efectos sobre la capacidad de las pupas de crear hipoxia. Los resultados de este estudio se discuten en base a las practicas actuales de produccion e irradiacion. (author)

Nestel, D.; Nemny-Lavy, E. [Department of Entomology, Institute of Plant Protection, Agricultural Research Organization, Volcani Center, P.O. Box 6, 50250 Beit-Dagan (Israel); Islam, S.M.; Wornoayporn, V.; Caceres, C. [Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Agency's Laboratories, A-2444 Seibersdorf (Austria)

2007-03-15

341

What is so special about male adolescent sexual offending? A review and test of explanations through meta-analysis.  

PubMed

We tested special and general explanations of male adolescent sexual offending by conducting a meta-analysis of 59 independent studies comparing male adolescent sex offenders (n = 3,855) with male adolescent non-sex offenders (n = 13,393) on theoretically derived variables reflecting general delinquency risk factors (antisocial tendencies), childhood abuse, exposure to violence, family problems, interpersonal problems, sexuality, psychopathology, and cognitive abilities. The results did not support the notion that adolescent sexual offending can be parsimoniously explained as a simple manifestation of general antisocial tendencies. Adolescent sex offenders had much less extensive criminal histories, fewer antisocial peers, and fewer substance use problems compared with non-sex offenders. Special explanations suggesting a role for sexual abuse history, exposure to sexual violence, other abuse or neglect, social isolation, early exposure to sex or pornography, atypical sexual interests, anxiety, and low self-esteem received support. Explanations focusing on attitudes and beliefs about women or sexual offending, family communication problems or poor parent-child attachment, exposure to nonsexual violence, social incompetence, conventional sexual experience, and low intelligence were not supported. Ranked by effect size, the largest group difference was obtained for atypical sexual interests, followed by sexual abuse history, and, in turn, criminal history, antisocial associations, and substance abuse. We discuss the implications of the findings for theory development, as well as for the assessment, treatment, and prevention of adolescent sexual offending. PMID:20565168

Seto, Michael C; Lalumière, Martin L

2010-07-01

342

Extra-marital sexual partnerships and male friendships in rural Malawi  

PubMed Central

Extra-marital sexual partnerships (EMSPs) are a major route of HIV/AIDS transmission in sub-Saharan Africa. In this paper, we investigate the roles of two types of male friendships – best friends and friends with whom they talk about AIDS – in determining whether men have EMSPs. Using data from men in rural Malawi, we find that men's current extra-marital sexual behavior is most closely correlated with their best friends', but that the behaviors of both types of friends are associated with men's subsequent EMSPs. These findings suggest that men's friendships could be used to help combat the AIDS epidemic. PMID:20531977

Clark, Shelley

2010-01-01

343

Analysis of mitochondrial DNA using amplified fragment length polymorphism markers of isonuclear allocytoplasmic male sterile wheat accessions and their maintainer lines.  

PubMed

To produce a good F1 hybrid variety wheat crop, it is necessary to explore novel cytoplasmic male sterility (CMS) lines and their maintainer line. This study aimed to identify cytoplasmic variation in three isonuclear-alloplasmic male sterile lines Aegilops kotschyi (Ae.kots) -90-110, Aegilops ventricosa (Ae.ven) -90-110, and Triticum spelta (T.spelta) -90-110 and their maintainer line, A-90-110, at the molecular level. Mitochondrial DNA (mtDNA) was isolated using a combination of centrifugation and density gradient ultracentrifugation, sucrose sedimentation, lysis with sodium dodecyl sulfate (SDS), potassium proteinase, and phenol/chloroform extraction methods. To detect mtDNA purity, specific primers were designed for nuclear (?-actin) and mitochondrial (COXIII) genes. Results indicated that the mtDNA was pure, and therefore suitable for polymerase chain reaction (PCR) and genetic analysis. Comparative analysis of mtDNA was conducted using amplified fragment length polymorphism (AFLP) markers. Reproducible polymorphisms were detected between the Aegilops and Triticum species and the male sterile lines. Four specific primers were screened from 64 AFLP marker primers, which provided the molecular basis for further studies investigating specific cytoplasmic male sterility characteristics. PMID:24301781

Ejaz, M; Qidi, Z; Gaisheng, Z; Qunzhu, W; Xinbo, Z

2013-01-01

344

Additional tests on the efficacy of ginger root oil in enhacing the mating competitiveness of sterile males of the Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recent studies have shown that exposure to the aroma of ginger root oil (Zingiber officinale Roscoe; termed GRO hereafter) increases the mating competitiveness of males of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann). This result suggests that pre-release exposure of sterile ...

345

MRG1-1 , a dominant allele that confers methomyl resistance in yeast expressing the cytoplasmic male sterility T- urf13 gene from maize  

Microsoft Academic Search

We have previously described a eukaryotic heterologous expression system, with the urf13TW gene in yeast, which mimics the disease susceptibility associated with the Texas cytoplasmic male sterility in maize. This yeast model was used to isolate yeast nuclear mutants conferring methomyl resistance. The genetic strategy we have developed focused on screening for nuclear dominant yeast mutations which restore methomyl resistance.

Nathalie Glab; Marie-Ange Teste; Piotr P. Slonimski

1994-01-01

346

Prevalence rates of male and female sexual violence perpetrators in a national sample of adolescents.  

PubMed

IMPORTANCE Sexual violence can emerge in adolescence, yet little is known about youth perpetrators-especially those not involved with the criminal justice system. OBJECTIVE To report national estimates of adolescent sexual violence perpetration and details of the perpetrator experience. DESIGN, SETTING, AND PARTICIPANTS Data were collected online in 2010 (wave 4) and 2011 (wave 5) in the national Growing Up With Media study. Participants included 1058 youths aged 14 to 21 years who at baseline read English, lived in the household at least 50% of the time, and had used the Internet in the last 6 months. Recruitment was balanced on youths' biological sex and age. MAIN OUTCOMES AND MEASURES Forced sexual contact, coercive sex, attempted rape, and completed rape. RESULTS Nearly 1 in 10 youths (9%) reported some type of sexual violence perpetration in their lifetime; 4% (10 females and 39 males) reported attempted or completed rape. Sixteen years old was the mode age of first sexual perpetration (n?=?18 [40%]). Perpetrators reported greater exposure to violent X-rated content. Almost all perpetrators (98%) who reported age at first perpetration to be 15 years or younger were male, with similar but attenuated results among those who began at ages 16 or 17 years (90%). It is not until ages 18 or 19 years that males (52%) and females (48%) are relatively equally represented as perpetrators. Perhaps related to age at first perpetration, females were more likely to perpetrate against older victims, and males were more likely to perpetrate against younger victims. Youths who started perpetrating earlier were more likely than older youths to get in trouble with caregivers; youths starting older were more likely to indicate that no one found out about the perpetration. CONCLUSIONS AND RELEVANCE Sexual violence perpetration appears to emerge earlier for males than females, perhaps suggesting different developmental trajectories. Links between perpetration and violent sexual media are apparent, suggesting a need to monitor adolescents' consumption of this material. Victim blaming appears to be common, whereas experiencing consequences does not. There is therefore urgent need for school programs that encourage bystander intervention as well as implementation of policies that could enhance the likelihood that perpetrators are identified. PMID:24100409

Ybarra, Michele L; Mitchell, Kimberly J

2013-12-01

347

Drug Use and Sexually Transmitted Diseases among Female and Male Arrested Youths  

PubMed Central

Knowledge of the rates and correlates of juvenile offenders’ sexually transmitted diseases (STD) has been limited to samples of incarcerated youths comprised mostly of males. Data collected on 442 female and 506 male youths processed at a centralized intake facility enabled us to study this important public health problem among a sample of juvenile offenders at the front end of the justice system. Female-male, multi-group latent class analyses identified two subgroups, High Risk and Lower Risk, of youths described by a latent construct of risk based on drug test results, STD test results, and a classification for the seriousness of arrest charge. The results found: (1) a similar classification distinguished High Risk and Lower Risk male and female youths, and (2) important gender group differences in sexual risk related factors (e.g., substance use during sexual encounters). Among the youths in this sample who tested positive for an STD, 66% of the girls and 57% of the boys were released back into the community after arrest. Overall, our findings raise serious public health and social welfare concerns, for both the youths and the community. Prevention and intervention implications of these findings are also discussed. PMID:18979194

Dembo, Richard; Belenko, Steven; Childs, Kristina; Wareham, Jennifer

2009-01-01

348

Interaction between temperature and male pheromone in sexual isolation in Drosophila melanogaster  

PubMed Central

In Drosophila, female hydrocarbons are known to be involved in premating isolation between different species and pheromonal races. The role of male-specific hydrocarbon polymorphism is not as well documented. The dominant cuticular hydrocarbon (CHC) in male D. melanogaster is usually 7-tricosene (7-T), with the exception of African populations, in which 7-pentacosene (7-P) is dominant. Here, we took advantage of a population from the Comoro Islands (Com), in which males fell on a continuum of low to high levels of 7-T, to perform temperature selection and selection on CHCs’ profiles. We conducted several experiments on the selected Com males to study the plasticity of their CHCs in response to temperature shift, their role in resistance to desiccation and in sexual selection. We then compared the results obtained for selected lines to those from three common laboratory strains with different and homogenous hydrocarbon profiles: CS, Cot and Tai. Temperature selection modified the CHC profiles of the Com males in few generations of selection. We showed that the 7-P/7-T ratio depends on temperature with generally more 7-P at higher temperatures and observed a relationship between chain length and resistance to desiccation in both temperature- and phenotypically selected Com lines. There was partial sexual isolation between the flies with clear-cut phenotypes within the phenotypically selected lines and the laboratory strains. These results indicate that the dominant male pheromones are under environmental selection and may have played a role in reproductive isolation. PMID:23944628

Bontonou, G; Denis, B; Wicker-Thomas, C

2013-01-01

349

Sexual maturation in common vole (Microtus arvalis) males raised under laboratory conditions.  

PubMed

The common vole is one ofthe most numerous rodents in Europe and Asia but its reproductive biology is not fully described. It is thought that females reach reproductive abilities at a very young age, however, there is no data concerning male sexual maturation. The aim of the present study was to determine the rate of sexual maturation of males of the common vole. Research was carried out on 4, 6, 8 and 10 week-old animals. Body, testes and accessory sex glands weights were compared to evaluate morphological development. Epididymal sperm quality was assessed by a motility test, sperm tail membrane integrity, viability, maturity and sperm head morphology. Moreover, the number of sperm cells in 1 mm3 of semen was evaluated. The largest body weights were observed in 8 and 10 week-old males, which also possessed the highest relative weights of gonads and accessory sex glands. These groups of males produce about 2 times more gametes than 6 week-old individuals. The highest seamen quality was noted in 8 and 10 week-old males. Based on the obtained results, it is concluded that among the investigated age groups the most appropriate male age for fertile copulation is between 8 and 10 weeks. PMID:25134343

Miska, Agata; Kruczek, Ma?gorzata; Kapusta, Joanna

2014-01-01

350

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

Microsoft Academic Search

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 (Oâ) in

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

2007-01-01

351

Improving panicle exsertion of rice cytoplasmic male sterile line by combination of artificial microRNA and artificial target mimic.  

PubMed

The adoption of hybrid rice caused the second leap in rice yield after the 'green revolution' and contributes substantially to food security of China and the world. However, almost all cytoplasmic male sterile lines (A lines) as females of hybrid rice have a natural deficiency of 'panicle enclosure', which blocks pollination between the A line and the fertility restorer line as the male (R line) of hybrid rice and decreases seed yield. In hybrid rice seed production, exogenous '920' (the active ingredient is gibberellin A3 ) must be applied to eliminate or alleviate panicle enclosure of the A line; however, this not only increases production cost and pollutes the environment, it also decreases seed quality. In this study, we designed a transgenic approach to improve plant height and panicle exsertion of the A line to facilitate hybrid rice production and maintain the semi-dwarf plant type of the hybrid. This approach comprising two components-artificial microRNA (amiRNA) and artificial target mimicry-can manipulate the differential expression of the endogenous Eui1 gene that is associated with rice internode elongation in the A line and the hybrid. amiRNA is a recently developed gene silencing method with high specificity, while target mimicry is a natural mechanism inhibiting the miRNA function that was also recently characterized. This approach provides a paradigm to tune the expression of endogenous genes to achieve the desired phenotype by combining amiRNA and artificial target mimicry technologies. PMID:23164055

Chen, Hao; Jiang, Shan; Zheng, Jie; Lin, Yongjun

2013-04-01

352

Sexual behavior attenuates the effects of chronic stress in body weight, testes, sexual accessory glands, and plasma testosterone in male rats.  

PubMed

The aim of this study was to evaluate whether continuous sexual behavior could attenuate the effects of chronic stress on spermatogenesis, sexual glands, plasma testosterone and corticosterone in sexually experienced male rats. Rats were exposed to stress by immersion in cold water (ICW) daily for 20 or 50 consecutive days. Plasma testosterone and corticosterone, masculine sexual behavior, as well as the number of offspring, the epithelial area of seminiferous, prostatic and seminal glands were assessed. In stressed males, body and testicular weights decreased, male sexual behavior was disrupted, and adrenal weights increased. In males stressed for 50 days, prostate and seminal glands had lower weights compared with controls. Prostate and seminal epithelial areas also decreased in these males. Seminiferous tubules in testes from rats stressed for 20 or 50 days showed several degenerative signs, such as vacuoles in the basal epithelium, with picnotic indicia; moderate to severe exfoliation of degenerative germinal cells in the tubule lumen was also observed. In males stressed for 50 days a significant decrease in seminiferous epithelial area was observed from stages I-VIII, regardless of copulation. The litters from females that copulated with males stressed for 50 days decreased significantly. Chronic stress caused increase in plasma levels of corticosterone, which were higher in males stressed for 20 days than in males stressed for 50 days. Testosterone decreased in stressed males and it was lower in males stressed for 50 days. In stressed males allowed to copulate, body and testicular weights were similar to controls. Adrenal, seminal glands, and prostate weights, as well as epithelial areas of males stressed for 50 days allowed to copulate were also similar to controls. Corticosterone was lower than in males stressed for 50 days, but still higher than in controls. Testosterone in males stressed for 50 days and allowed to copulate was higher than in stressed males not allowed to copulate and control males without copulation, but still lower than in control copulating males. These results show that chronic stress causes germ cell loss in testes and a decrease in prostate and seminal epithelium, possibly as a result of testosterone decrease, affecting fertility. Continuous copulation can attenuate the effects of stress on testosterone levels and on the epithelial area in male sexual glands, but not on the seminiferous epithelium after 50 days of stress. PMID:25236886

Retana-Márquez, S; Vigueras-Villaseñor, R M; Juárez-Rojas, L; Aragón-Martínez, A; Torres, G Reyes

2014-11-01

353

Characteristics of sex partners and sexual partnership correlates of inconsistent condom use among male injection drug users in India.  

PubMed

Previous studies have established the risky behaviors of IDUs in India, and that IDUs are sexually active; however, there is a need to better understand the nature of sexual partnerships of IDUs. A total of 783 (Delhi) and 766 (Imphal) male IDUs were recruited into the study through respondent-driven sampling. We examined characteristics of sex partners of male IDUs and individual and sexual partnership characteristics associated with unprotected sex in Delhi and Imphal. While 16.8% of sexual partnerships in Delhi were male-to-male, there were almost no male-to-male partnerships in Imphal. The majority of partners of male IDUs in Delhi (82.5%) and Imphal (92.3%) do not inject drugs, with the exception of male partners of male IDUs in Delhi. Commercial partners (females: 58.3%; males: 71.3%) were the most common type of sex partners of male IDUs in Delhi, while regular partners (65.2%) were the most common type of sex partners in Imphal. In Delhi, characteristics of sex partners significantly associated with unprotected sex were being male/transgender (AOR 2.2; 95% CI: 1.2-4.0), being a regular (AOR 5.1; 95% CI: 2.8-9.4) or non-regular partner (AOR 2.7; 95% CI: 1.7- 4.5), and sharing needles/syringes with the index IDU (AOR 2.8; 95% CI: 1.4-5.3). In Imphal, partner characteristics associated with unprotected sex were being a regular (AOR 10.1; 95% CI: 41-25.1) or non-regular partner (AOR 3.4; 95% CI: 1.5-7.6), and living outside of town or state (AOR 3.3; 95% CI: 1.2-9.6). Enhanced understanding of disassortative sexual mixing and context of unprotected sex within sexual partnerships may enhance sexual risk reduction interventions for IDUs. PMID:25427360

Tun, Waimar; Bhattacharya, Aruna; Apicella, Louis; Shasikumar Singh, Yumnam; Lewis, Dean

2014-07-01

354

DMRT1 protects male gonadal cells from retinoid-dependent sexual transdifferentiation.  

PubMed

Mammalian sex determination initiates in the fetal gonad with specification of bipotential precursor cells into male Sertoli cells or female granulosa cells. This choice was long presumed to be irreversible, but genetic analysis in the mouse recently revealed that sexual fates must be maintained throughout life. Somatic cells in the testis or ovary, even in adults, can be induced to transdifferentiate to their opposite-sex equivalents by loss of a single transcription factor, DMRT1 in the testis or FOXL2 in the ovary. Here, we investigate what mechanism DMRT1 prevents from triggering transdifferentiation. We find that DMRT1 blocks testicular retinoic acid (RA) signaling from activating genes normally involved in female sex determination and ovarian development and show that inappropriate activation of these genes can drive sexual transdifferentiation. By preventing activation of potential feminizing genes, DMRT1 allows Sertoli cells to participate in RA signaling, which is essential for reproduction, without being sexually reprogrammed. PMID:24856513

Minkina, Anna; Matson, Clinton K; Lindeman, Robin E; Ghyselinck, Norbert B; Bardwell, Vivian J; Zarkower, David

2014-06-01

355

Indiscriminate Males: Mating Behaviour of a Marine Snail Compromised by a Sexual Conflict?  

PubMed Central

Background In promiscuous species, male fitness is expected to increase with repeated matings in an open-ended fashion (thereby increasing number of partners or probability of paternity) whereas female fitness should level out at some optimal number of copulations when direct and indirect benefits still outweigh the costs of courtship and copulation. After this fitness peak, additional copulations would incur female fitness costs and be under opposing selection. Hence, a sexual conflict over mating frequency may evolve in species where females are forced to engage in costly matings. Under such circumstance, if females could avoid male detection, significant fitness benefits from such avoidance strategies would be predicted. Methodology/Principal Findings Among four Littorina species, one lives at very much higher densities and has a longer mating season than the other three species. Using video records of snail behaviour in a laboratory arena we show that males of the low-density species discriminate among male and female mucous trails, trailing females for copulations. In the high-density species, however, males fail to discriminate between male and female trails, not because males are unable to identify female trails (which we show using heterospecific females), but because females do not, as the other species, add a gender-specific cue to their trail. Conclusions/Significance We conclude that there is likely a sexual conflict over mating frequency in the high-density species (L. saxatilis) owing to females most likely being less sperm-limited in this species. This has favoured the evolution of females that permanently or optionally do not release a cue in the mucus to decrease excessive and costly matings resulting in unusually high frequencies of male-male copulating attempts in the wild. This is one of few examples of masking gender identity to obtain fewer matings. PMID:20711254

Johannesson, Kerstin; Saltin, Sara H.; Duranovic, Iris; Havenhand, Jon N.; Jonsson, Per R.

2010-01-01

356

The mesolimbic system participates in the naltrexone-induced reversal of sexual exhaustion: opposite effects of intra-VTA naltrexone administration on copulation of sexually experienced and sexually exhausted male rats.  

PubMed

Male rats allowed to copulate until reaching sexual exhaustion exhibit a long-lasting sexual behavior inhibition (around 72 h) that can be reversed by systemic opioid receptor antagonist administration. Copulation activates the mesolimbic dopaminergic system (MLS) and promotes endogenous opioid release. In addition, endogenous opioids, acting at the ventral tegmental area (VTA), modulate the activity of the MLS. We hypothesized that endogenous opioids participate in the sexual exhaustion phenomenon by interacting with VTA opioid receptors and consequently, its reversal by opioid antagonists could be exerted at those receptors. In this study we determined the effects of intra-VTA infusion of different doses of the non-specific opioid receptor antagonist naltrexone (0.1-1.0 ?g/rat) on the already established sexual behavior inhibition of sexually exhausted male rats. To elucidate the possible involvement of VTA ?-opioid receptors in the naltrexone-mediated reversal of sexual exhaustion, the effects of different doses of the selective ?-opioid receptor antagonist, naltrindole (0.03-1.0 ?g/rat) were also tested. Results showed that intra-VTA injection of 0.3 ?g naltrexone reversed the sexual inhibition of sexually exhausted rats, evidenced by an increased percentage of animals capable of showing two successive ejaculations. Intra-VTA infused naltrindole did not reverse sexual exhaustion at any dose. It is concluded that the MLS is involved in the reversal of sexual exhaustion induced by systemic naltrexone, and that ?-, but not ?-opioid receptors participate in this effect. Intra-VTA naltrexone infusion to sexually experienced male rats had an inhibitory effect on sexual activity. The opposite effects of intra-VTA naltrexone on male rat sexual behavior expression of sexually experienced and sexually exhausted rats is discussed. PMID:23933468

Garduño-Gutiérrez, René; León-Olea, Martha; Rodríguez-Manzo, Gabriela

2013-11-01

357

Unique changes in mitochondrial genomes associated with reversions of S-type cytoplasmic male sterility in maizemar.  

PubMed

Cytoplasmic male sterility (CMS) in plants is usually associated with the expression of specific chimeric regions within rearranged mitochondrial genomes. Maize CMS-S plants express high amounts of a 1.6-kb mitochondrial RNA during microspore maturation, which is associated with the observed pollen abortion. This transcript carries two chimeric open reading frames, orf355 and orf77, both unique to CMS-S. CMS-S mitochondria also contain free linear DNA plasmids bearing terminal inverted repeats (TIRs). These TIRs recombine with TIR-homologous sequences that precede orf355/orf77 within the main mitochondrial genome to produce linear ends. Transcription of the 1.6-kb RNA is initiated from a promoter within the TIRs only when they are at linear ends. Reversions of CMS-S to fertility occur in certain nuclear backgrounds and are usually associated with loss of the S plasmids and/or the sterility-associated region. We describe an unusual set of independently recovered revertants from a single maternal lineage that retain both the S plasmids and an intact orf355/orf77 region but which do not produce the 1.6-kb RNA. A 7.3-kb inversion resulting from illegitimate recombination between 14-bp microrepeats has separated the genomic TIR sequences from the CMS-associated region. Although RNAs containing orf355/orf77 can still be detected in the revertants, they are not highly expressed during pollen development and they are no longer initiated from the TIR promoter at a protein-stabilized linear end. They appear instead to be co-transcribed with cytochrome oxidase subunit 2. The 7.3-kb inversion was not detected in CMS-S or in other fertile revertants. Therefore, this inversion appears to be a de novo mutation that has continued to sort out within a single maternal lineage, giving rise to fertile progeny in successive generations. PMID:21858103

Matera, John T; Monroe, Jessica; Smelser, Woodson; Gabay-Laughnan, Susan; Newton, Kathleen J

2011-01-01

358

Variation in male sailfin molly, preference for female size: does sympatry with sexual parasites, drive preference for smaller conspecifics?  

Microsoft Academic Search

Male sailfin mollies (Poecilia latipinna )a re sexually parasitized by gyno genetic Amazon mollies (Poecilia formosa). In areas of sympatry, Amazon mollies are frequently larger than female sailfin mollies. In sympatry, selection may favor males that prefer smaller conspecific mates (avoid mismating with Amazon mollies), or selection may favor males that prefer larger conspecific mates (higher fecundity). To explore this

Caitlin R. Gabor; Rosalinda Gonzalez; Michelle Parmley; Andrea S. Aspbury

2009-01-01

359

Effects of exposure to a mobile phone on sexual behavior in adult male rabbit: an observational study  

Microsoft Academic Search

The accumulating effects of exposure to electromagnetic radiation emitted by a conventional mobile phone (MP) on male sexual behaviour have not yet been analyzed. Therefore, we studied these effects in 18 male rabbits that were randomly divided into phone and control groups. Six female teasers were taken successively to the male's cage and the copulatory behavior was recorded. Serum total

N Salama; T Kishimoto; H-o Kanayama; S Kagawa

2010-01-01

360

Increased vigilance of paired males in sexually dimorphic species: distinguishing between alternative explanations in wintering Eurasian wigeon  

Microsoft Academic Search

In animal pairs, males are often more vigilant than females. This is generally assumed to result from mate guarding (either against predators or other males). However, when males have conspicuous secondary sexual characteristics, they could be constrained to be more vigilant because of a higher predation risk than females. We attempted to distinguish between the \\

Matthieu Guillemain; Richard W. G. Caldow; Kathy H. Hodder; John D. Goss-Custard

2003-01-01

361

Sexually explicit media on the internet: a content analysis of sexual behaviors, risk, and media characteristics in gay male adult videos.  

PubMed

Recent research suggests that viewing sexually explicit media (SEM), i.e., adult videos, may influence sexual risk taking among men who have sex with men. Despite this evidence, very little is known about the content of gay male SEM on the Internet, including the prevalence of sexual risk behaviors and their relation to video- and performer-characteristics, viewing frequency, and favorability. The current study content analyzed 302 sexually explicit videos featuring male same-sex performers that were posted to five highly trafficked adult-oriented websites. Findings revealed that gay male SEM on the Internet features a variety of conventional and nonconventional sexual behaviors. There was a substantial prevalence of unprotected anal intercourse (UAI) (34 %) and was virtually the same as the prevalence of anal sex with a condom (36 %). The presence of UAI was not associated with video length, amateur production, number of video views, favorability, or website source. However, the presence of other potentially high-risk behaviors (e.g., ejaculation in the mouth, and ejaculation on/in/rubbed into the anus) was associated with longer videos, more views, and group sex videos (three or more performers). The findings of high levels of sexual risk behavior and the fact that there was virtually no difference in the prevalence of anal sex with and without a condom in gay male SEM have important implications for HIV prevention efforts, future research on the role of SEM on sexual risk taking, and public health policy. PMID:23733156

Downing, Martin J; Schrimshaw, Eric W; Antebi, Nadav; Siegel, Karolynn

2014-05-01

362

Elevated sexual risk behaviors among postincarcerated young african american males in the South.  

PubMed

The dramatic racial disparities in the rates of HIV/STIs(sexually transmitted infections) among African Americans make understanding broader structural factors that increase the risk for HIV/STIs crucial. The current study of young 564 African American men attending STI clinics investigated whether those who had ever been incarcerated reported recent sexual behaviors relatively more risky than their counterparts who had never been incarcerated. Participants were recruited from clinics treating STIs in three southern U.S. cities. Males 15 to 23 years of age who identified as Black/African American and reported recent (past 2 months) sexual activity were eligible. Linear mixed-effects models and generalized estimating equation models were used to assess associations between baseline incarceration history and sexual risk behavior over a 6-month follow-up period. Mean age was 19.6 years (SD = 1.87). At baseline, 240 (42.6%) men reported history of incarceration. Incarceration history predicted several risk behaviors over a 6-month follow-up period. Compared with those with no incarceration history, men previously incarcerated reported a desire to conceive a pregnancy (? = .40, p = .02), were less likely to have used a condom at last sex act (odds ratio = .91, p = .02) and were more likely to have used drugs and alcohol before sex in the past 2 months (? = .69, p < .001; ? = .41, p < .001). A history of incarceration may influence the sexual risk behavior of young African American males. Prevention programs and interventions should intensify support for postincarceration African American males to help mitigate this behavior. PMID:24794821

Ricks, JaNelle M; Crosby, Richard A; Terrell, Ivy

2015-03-01

363

Sex hormones and pituitary function in male epileptic patients with altered or normal sexuality.  

PubMed

Male epileptic patients frequently complain of sexual dysfunction, particularly impotence and loss of libido. Epilepsy itself, antiepileptic drugs (AEDs), and psychosocial factors are believed to contribute to impaired sexuality. We studied luteinizing hormone (LH) pulsatile secretion, gonadotropin, and prolactin (PRL) responses to LH-releasing hormone (LHRH) and thyrotropin-releasing hormone (TRH) in 37 adult male epileptic patients receiving AED monotherapy who were seizure-free and had normal EEGs. Sexuality was assessed by psychological interview. Impotence was diagnosed in 8 patients (in 2 combined with loss of sexual desire). The occurrence of hyposexuality (approximately 20%) was independent of epilepsy syndrome or AED. No change in total testosterone (T) level was observed. Free T (fT) and dihydrotestosterone (DHT) levels were lower and sex hormone binding globulin (SHBG) levels were higher in epileptic subjects than in healthy controls, but a statistically significant difference was not observed between hypo- and normosexual patients. In impotent epileptic patients, estradiol (E2) levels were significantly increased as compared with those of patients with preserved sexuality and of healthy controls. The unbalanced relation between androgen and E2 levels was emphasized by decreased T/E2, fT/E2, and DHT/E2 ratios obtained in hyposexual epileptic patients. In this group, LHRH induced blunted LH peaks. No changes were noted in LH pulsatility features. These findings of higher E2 levels and of decreased LH response to LHRH administration in some epileptic patients with impaired sexuality, may suggest they have subclinical hypogonadotropic hypogonadism. PMID:7607114

Murialdo, G; Galimberti, C A; Fonzi, S; Manni, R; Costelli, P; Parodi, C; Solinas, G P; Amoretti, G; Tartara, A

1995-04-01

364

Evolution of male life histories and age-dependent sexual signals under female choice  

PubMed Central

Sexual selection theory models evolution of sexual signals and preferences using simple life histories. However, life-history models predict that males benefit from increasing sexual investment approaching old age, producing age-dependent sexual traits. Age-dependent traits require time and energy to grow, and will not fully mature before individuals enter mating competition. Early evolutionary stages pose several problems for these traits. Age-dependent traits suffer from strong viability selection and gain little benefit from mate choice when rare. Few males will grow large traits, and they will rarely encounter choosy females. The evolutionary origins of age-dependent traits therefore remain unclear. I used numerical simulations to analyze evolution of preferences, condition (viability) and traits in an age-structured population. Traits in the model depended on age and condition (“good genes”) in a population with no genetic drift. I asked (1) if age-dependent indicator traits and their preferences can originate depending on the strength of selection and the size of the trait; (2) which mode of development (age-dependent versus age-independent) eventually predominates when both modes occur in the population; and (3) if age-independent traits can invade a population with age-dependent traits. Age-dependent traits evolve under weaker selection and at smaller sizes than age-independent traits. This result held in isolation and when the types co-occur. Evolution of age-independent traits depends only on trait size, whereas evolution of age-dependent traits depends on both strength of selection and growth rate. Invasion of age-independence into populations with established traits followed a similar pattern with age-dependence predominating at small trait sizes. I suggest that reduced adult mortality facilitates sexual selection by favoring the evolution of age-dependent sexual signals under weak selection. PMID:24392289

2013-01-01

365

Impaired male sexual behavior in activin receptor type II knockout mice.  

PubMed

Integration of multiple hormonal and neuronal signaling pathways in the medial preoptic area (mPOA) is required for elicitation of male sexual behavior in most vertebrates. Perturbation of nitric oxide synthase (NOS) activity in the mPOA causes significant defects in male sexual behavior. Although activins and their signaling components are highly expressed throughout the brain, including the mPOA, their functional significance in the central nervous system (CNS) is unknown. Here, we demonstrate a neurophysiologic role for activin signaling in male reproductive behavior. Adult activin receptor type II null (Acvr2-/-) male mice display multiple reproductive behavioral deficits, including delayed initiation of copulation, reduced mount, and intromission frequencies, and increased mount, intromission, and ejaculation latencies. These behavioral defects in the adult mice are independent of gonadotropin-releasing hormone (GnRH) homeostasis or mating-induced changes in luteinizing hormone (LH) and testosterone levels. The impairment in behavior can be correlated to the nitric oxide content in the CNS because Acvr2-/- males have decreased NOS activity in the mPOA but not the rest of the hypothalamus or cortex. Olfactory acuity tests confirmed that Acvr2-/- mice have no defects in general odor or pheromone recognition. In addition, motor functions are not impaired and the mutants demonstrate normal neuromuscular coordination and balance. Furthermore, the penile histology in mutant mice appears normal, with no significant differences in the expression of penile differentiation marker genes compared with controls, suggesting the observed behavioral phenotypes are not due to structural defects in the penis. Our studies identify a previously unrecognized role of activin signaling in male sexual behavior and suggest that activins and/or related family members are upstream regulators of NOS activity within the mPOA of the forebrain. PMID:16093358

Ma, Xiaoping; Reyna, Andrea; Mani, Shailaja K; Matzuk, Martin M; Kumar, T Rajendra

2005-12-01

366

Capture of Mediterranean fruit flies (Diptera: Tephritidae) in dry traps baited with a food-based attractant and Jackson traps baited with trimedlure during sterile male release in Guatemala.  

PubMed

Captures of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in Jackson traps baited with trimedlure were compared with captures in cylindrical open-bottom dry traps baited with a food-based synthetic attractant (ammonium acetate, putrescine, and trimethylamine). Tests were conducted in Guatemala during a sterile male release program in an area where wild flies were present in low numbers. More wild and sterile females were captured in food-based traps, and more wild and sterile males were captured in trimedlure traps. The food-based traps captured almost twice as many total (male plus female) wild flies as the trimedlure traps, but the difference was not significant. Females made up approximately 60% of the wild flies caught in the food-based attractant traps; the trimedlure traps caught no females. The ratio of capture of males in trimedlure traps to food-based traps was 6.5:1 for sterile and 1.7:1 for wild flies. Because fewer sterile males are captured in the food-based traps, there is a reduction in the labor-intensive process of examining flies for sterility. The results indicate that traps baited with food-based attractants could be used in place of the Jackson/trimedlure traps for C. capitata sterile release programs because they can monitor distributions of sterile releases and detect wild fly populations effectively; both critical components of fruit fly eradication programs by using the sterile insect technique. PMID:15666775

Midgarden, David; Ovalle, Oscar; Epsky, Nancy D; Puche, Helena; Kendra, Paul E; Rendon, Pedro; Heath, Robert R

2004-12-01

367

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

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

Tao, Yun; Chen, Sining; Hartl, Daniel L; Laurie, Cathy C

2003-01-01

368

HIV sexual risk behaviors and multilevel determinants among male labor migrants from Tajikistan.  

PubMed

The purpose of this study was to investigate HIV risk behaviors and their multilevel determinants in male labor migrants from Tajikistan to Moscow. In Russia and Central Asia, where AIDS rates are amongst the world's highest, conditions in both sending and receiving countries pose serious challenges to HIV prevention. A survey of Tajik married male seasonal labor migrants in Moscow was completed by 200 workers from 4 bazaars and 200 workers from 18 construction sites as part of a mixed method study. The quantitative results indicated that male labor migrants were at risk for HIV due to higher sexual behaviors including sexual relations with sex workers (92 %), multiple partnering in the past month (86 %), unprotected sex with sex workers (33 %), and reduced frequency of condom use while drinking alcohol (57 %). Multivariate tests indicated the multilevel factors that increased HIV sexual risks including: pre-migration factors (e.g. used sex workers in Tajikistan); migrant work and lifestyle factors (e.g. greater number of times visited Moscow); migrant sexual and relational factors (e.g. regular partner in Moscow); and migrant health and mental health factors (e.g. increased frequency of alcohol use). Qualitative findings from longitudinal ethnographic interviews and observations of a subset of 40 purposively sampled Tajik male migrants demonstrated how these multilevel pre-migration and migration factors account for HIV risk and protective behaviors in context. These findings underscore the seriousness of HIV risk for labor migrants and call both for multilevel approaches to prevention and for further study. PMID:23054537

Weine, Stevan; Bahromov, Mahbat; Loue, Sana; Owens, Linda

2013-08-01

369

Sexually disrupting effects of nonylphenol and diethylstilbestrol on male silver carp ( Carassius auratus) in aquatic microcosms  

Microsoft Academic Search

Based on detected nonylphenol (NP) levels in aquaculture water, this study investigated sexually disrupting effects in mature male silver carp (Carassius auratus) exposed to NP and a positive control diethylstilbestrol (DES). The combined evidences of steroid hormone (17?-estradiol, estrone and testosterone) levels and hispathological pictures showed that NP (?10?g\\/L) and DES could exert estrogenic effects through indirect mechanisms [i.e. increased

Lihua Yang; Li Lina; Shaoping Weng; Zhiqin Feng; Tiangang Luan

2008-01-01

370

Psychopathy traits and parental dysfunction in sexual offending and general delinquent adolescent males  

Microsoft Academic Search

The failure to account for differences between adolescent males who offend against children and those who offend against peers may account for the similarities found between sex-offending samples and non-sexual delinquents. Psychopathy traits (grandiosity, impulsivity, lack of empathy, interpersonally exploitative and risk-taking) and antisocial behaviour, including behaviours and age of onset for delinquent behaviours and drug use, were explored in

Jason D. Netland; Michael H. Miner

2012-01-01

371

Psychopathy traits and parental dysfunction in sexual offending and general delinquent adolescent males  

Microsoft Academic Search

The failure to account for differences between adolescent males who offend against children and those who offend against peers may account for the similarities found between sex-offending samples and non-sexual delinquents. Psychopathy traits (grandiosity, impulsivity, lack of empathy, interpersonally exploitative and risk-taking) and antisocial behaviour, including behaviours and age of onset for delinquent behaviours and drug use, were explored in

Jason D. Netland; Michael H. Miner

2011-01-01

372

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

Microsoft Academic Search

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

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

1998-01-01

373

Maize Male sterile 8 (Ms8), a putative ?-1,3-galactosyltransferase, modulates cell division, expansion, and differentiation during early maize anther development.  

PubMed

Precise somatic and reproductive cell proliferation and differentiation in anthers are crucial for male fertility. Loss of function of the Male sterile 8 (Ms8) gene causes male sterility with multiple phenotypic defects first visible in the epidermal and tapetal cells. Here, we document the cloning of Ms8, which is a putative ?-1,3-galactosyltransferase. Ms8 transcript is abundant in immature anthers with a peak at the meiotic stage; RNA expression is highly correlated with protein accumulation. Co-immunoprecipitation coupled with mass spectrometry sequencing identified several MS8-associated proteins, including arabinogalactan proteins, prohibitins, and porin. We discuss the hypotheses that arabinogalactan protein might be an MS8 substrate and that MS8 might be involved in maintenance of mitochondrial integrity. PMID:23887707

Wang, Dongxue; Skibbe, David S; Walbot, Virginia

2013-12-01

374

Circumstances surrounding male sexual assault and rape: findings from the National Violence Against Women Survey.  

PubMed

Much work in the area of male sexual assault and rape relies on small clinical samples. From these samples, researchers reported that most male victims were physically injured during the attack and that penetration occurred. This work rests on a subsample of 219 men from the 1994-1996 Violence and Threats of Violence Against Women and Men in the United States Survey. Findings from the National Violence Against Women Survey (NVAW) show that the vast majority of male sexual assault victims reported that they were not physically injured during the assault, that a weapon was not used, that there was no substance use at the time of the assault, and that penetration did not occur. Only 29% of male respondents in the NVAW sought medical or psychological help after the assault. Prior work may have overrepresented men who reported being physically injured and/or penetrated. An analysis is presented of how those who presented for help in the NVAW differ from the whole sample. Results show that men who presented for help were more likely to have reported being physically injured during the assault and that penetration occurred. Thus, findings from prior work make sense; however, they may not be representative of male assault victims as a whole. PMID:18981191

Light, David; Monk-Turner, Elizabeth

2009-11-01

375

Effect of Bombax ceiba L. on spermatogenesis, sexual behaviour and erectile function in male rats.  

PubMed

A number of herbal drugs are advocated in the traditional Ayurvedic literature for the improvement of overall sexual function. Young roots of Bombax ceiba Linn. (Fam. Bombacaceae) [correction added after online publication 1 August 2011: the family of Bombax ceiba was incorrectly mentioned as Orchidaceae. It has been corrected to Bombacaceae] also known as Semal Musli are used traditionally in Indian subcontinent as sexual stimulant. Its juice is considered nutritive and restorative tonic. Lyophilised aqueous extract of roots was studied for effect on sexual behaviour and spermatogenesis in male albino rats. Administration of 100 mg Kg(-1) body weight of aqueous extract influenced the five parameters evaluated in vivo. Sexual behaviour analysis in the presence of a female rate, serum testosterone level, anabolic effects, epididymal sperm count and seminal fructose level were the parameters evaluated. In B. ceiba extract-treated animals, a gain in body and sexual organ weights was observed. Mount, intromission and ejaculation frequencies were significantly improved (P < 0.05). An increase in serum testosterone levels was also observed, but it was not statistically significant (P > 0.05). Seminal fructose content and epididymal sperm count were significantly improved as well. Penile erection index was also higher compared to control group animals. Hesitation time was significantly reduced (P < 0.01), and copulatory rate was doubled in treated animals compared with control group animals. PMID:21806665

Bhargava, C; Thakur, M; Yadav, S K

2012-05-01

376

Prospective Predictors of Technology-Based Sexual Coercion by College Males  

PubMed Central

Objective Technology-based coercive behavior (TBC) represents an emerging public health problem. This study contributes to the literature by identifying prospective individual-, social-, and community-level predictors of TBC. Method Data were collected from 800 males who participated in a prospective study on attitudes and behaviors regarding relationships with women. Variables across multiple ecological layers were used to predict TBC. Results Bivariate analyses indicated that 16 of the 17 risk variables significantly predicted TBC including anger, impulsivity, sexual compulsivity, hostility towards women, rape supportive beliefs, high-risk drinking, childhood sexual abuse, interparental conflict, peer pressure to engage in sex, peer approval of forced sex, number of sexual partners, perceived negative sanctions for sexual aggression, exposure to pornography, and participation in varsity sports, student government, and religious groups. Multivariate regression analyses indicated five variables uniquely accounted for TBC behaviors, including rape supportive beliefs, peer approval of forced sex, number of sexual partners, exposure to pornography, and participation in student government. Conclusions Our findings that TBC can be prospectively predicted by these risk factors suggest that computer-based technology interventions focusing on these factors through social network ads that promote reflection on healthy social and romantic relationship behaviors and attitudes could help prevent and reduce TBC. PMID:24073356

Thompson, Martie P.; Morrison, Deidra J.

2013-01-01

377

Transgenic rescue of ataxia mice reveals a male-specific sterility defect  

PubMed Central

Homozygous ataxia (axJ) mice have reduced expression of ubiquitin-specific protease 14 (Usp14), resulting in severe neuromuscular defects and death by 2 months of age. Transgenic expression of Usp14 exclusively in the nervous system of axJ mice (axJ-Tg) prevents early lethality and restores motor system function to the axJ mice, enabling an analysis of the reproductive capabilities of Usp14-deficient mice. Although female axJ-Tg mice had a 75% reduction of Usp14 in the ovaries, they were able to produce normal litters. Ovary transfer experiments also demonstrated that the ovaries of axJ mice were capable of producing viable pups. In contrast, male axJ and axJ-Tg mice displayed a 50% reduction in testicular Usp14 levels and were infertile, indicating that Usp14 is required for development and function of the male reproductive system. Immunohistochemistry experiments showed that Usp14 is found in the redundant nuclear envelope and cytoplasmic droplet of epididymal spermatozoa. Analysis of axJ testes demonstrated a 50% reduction in testis weight, a 100-fold reduction in sperm number and the presence of abnormal spermatozoa in the epididymis. Histological examination of the Usp14-deficient testes revealed abnormal spermatogenesis and the presence of degenerating germ cells, indicating that Usp14 and the ubiquitin proteasome system are required for spermatid differentiation during spermiogenesis. PMID:18926813

Crimmins, Stephen; Sutovsky, Miriam; Chung, Ping-Chen; Huffman, Alexis; Wheeler, Crystal; Swing, Deborah A.; Roth, Kevin; Wilson, Julie; Sutovsky, Peter; Wilson, Scott

2009-01-01

378

Aerodynamic costs of long tails in male barn swallows Hirundo rustica and the evolution of sexual size dimorphism  

Microsoft Academic Search

Exaggerated tail feathers of birds constitute a standard example of evolution of extravagant characters due to sexual selection. Such secondary sexual traits are assumed to be costly to produce and maintain, and they usually are accompanied by morpho- logical adaptations that tend to reduce their costs. The aerodynamic costs for male barn swallows Hirundo rustica of having long tails were

Andres Barbosa; Anders Pape Møller

1999-01-01

379

Prevalence of Same-Sex Sexual Behavior and Associated Characteristics among Low-Income Urban Males in Peru  

Microsoft Academic Search

Background. Peru has a concentrated HIV epidemic in which men who have sex with men are particularly vulnerable. We describe the lifetime prevalence of same-sex sexual contact and associated risk behaviors of men in Peru's general population, regardless of their sexual identity. Methods and Results. A probability sample of males from low-income households in three Peruvian cities completed an epidemiologic

Jesse L. Clark; Carlos F. Caceres; Andres G. Lescano; Kelika A. Konda; Segundo R. Leon; Franca R. Jones; Susan M. Kegeles; Jeffrey D. Klausner; Thomas J. Coates

2007-01-01

380

Sexual isolation of male moths explained by a single pheromone response QTL containing four receptor genes.  

PubMed

Long distance sexual communication in moths has fascinated biologists because of the complex, precise female pheromone signals and the extreme sensitivity of males to specific pheromone molecules. Progress has been made in identifying some genes involved in female pheromone production and in male response. However, we have lacked information on the genetic changes involved in evolutionary diversification of these mate-finding mechanisms that is critical to understanding speciation in moths and other taxa. We used a combined quantitative trait locus (QTL) and candidate gene approach to determine the genetic architecture of sexual isolation in males of two congeneric moths, Heliothis subflexa and Heliothis virescens. We report behavioral and neurophysiological evidence that differential male responses to three female-produced chemicals (Z9-14:Ald, Z9-16:Ald, Z11-16:OAc) that maintain sexual isolation of these species are all controlled by a single QTL containing at least four odorant receptor genes. It is not surprising that pheromone receptor differences could control H. subflexa and H. virescens responses to Z9-16:Ald and Z9-14:Ald, respectively. However, central rather than peripheral level control over the positive and negative responses of H. subflexa and H. virescens to Z11-16:OAc had been expected. Tight linkage of these receptor genes indicates that mutations altering male response to complex blends could be maintained in linkage disequilibrium and could affect the speciation process. Other candidate genes such as those coding for pheromone binding proteins did not map to this QTL, but there was some genetic evidence of a QTL for response to Z11-16:OH associated with a sensory neuron membrane protein gene. PMID:20404144

Gould, Fred; Estock, Marie; Hillier, N Kirk; Powell, Bekah; Groot, Astrid T; Ward, Catherine M; Emerson, Jennifer L; Schal, Coby; Vickers, Neil J

2010-05-11

381

Fertility, sexuality and testicular adrenal rest tumors in adult males with congenital adrenal hyperplasia  

PubMed Central

Objective Fertility in males with congenital adrenal hyperplasia (CAH) is reported from normal to severely impaired. Therefore, we investigated fertility/fecundity, social/sexual situation, and pituitary–gonadal function in CAH males. Subjects and methods The patient cohort comprised 30 males, aged 19–67 years, with 21-hydroxylase deficiency. Their fertility was compared with age-matched national population data. For the evaluation of social/sexual factors and hormone status, age-matched controls were recruited (n=32). Subgroups of different ages (<30 years and older) and CYP21A2 genotypes (null (severe salt-wasting (SW)), I2splice (milder SW), and I172N (simple virilizing)) were also studied. Patients underwent testicular ultrasound examination (n=21) and semen analysis (n=14). Results Fertility was impaired in CAH males compared with national data (0.9±1.3 vs 1.8±0.5 children/father, P<0.001). There were no major differences in social and sexual factors between patients and controls apart from more fecundity problems, particularly in the I172N group. The patients had lower testosterone/estradiol (E2) ratio and inhibin B, and higher FSH. The semen samples were pathological in 43% (6/14) of patients and sperm concentration correlated with inhibin B and FSH. Testicular adrenal rest tumors (TARTs) were found in 86% (18/21). Functional testicular volume correlated positively with the testosterone/E2 ratio, sperm concentration, and inhibin B. Patients with pathological semen had increased fat mass and indications of increased cardiometabolic risk. Conclusions Fertility/fecundity was impaired in CAH males. The frequent occurrence of TARTs resulting in testicular insufficiency appears to be the major cause, but other factors such as elevated fat mass may contribute to a low semen quality. PMID:22157069

Falhammar, Henrik; Nyström, Helena Filipsson; Ekström, Urban; Granberg, Seth; Wedell, Anna; Thorén, Marja

2012-01-01

382

Sexual isolation of male moths explained by a single pheromone response QTL containing four receptor genes  

PubMed Central

Long distance sexual communication in moths has fascinated biologists because of the complex, precise female pheromone signals and the extreme sensitivity of males to specific pheromone molecules. Progress has been made in identifying some genes involved in female pheromone production and in male response. However, we have lacked information on the genetic changes involved in evolutionary diversification of these mate-finding mechanisms that is critical to understanding speciation in moths and other taxa. We used a combined quantitative trait locus (QTL) and candidate gene approach to determine the genetic architecture of sexual isolation in males of two congeneric moths, Heliothis subflexa and Heliothis virescens. We report behavioral and neurophysiological evidence that differential male responses to three female-produced chemicals (Z9-14:Ald, Z9-16:Ald, Z11-16:OAc) that maintain sexual isolation of these species are all controlled by a single QTL containing at least four odorant receptor genes. It is not surprising that pheromone receptor differences could control H. subflexa and H. virescens responses to Z9-16:Ald and Z9-14:Ald, respectively. However, central rather than peripheral level control over the positive and negative responses of H. subflexa and H. virescens to Z11-16:OAc had been expected. Tight linkage of these receptor genes indicates that mutations altering male response to complex blends could be maintained in linkage disequilibrium and could affect the speciation process. Other candidate genes such as those coding for pheromone binding proteins did not map to this QTL, but there was some genetic evidence of a QTL for response to Z11-16:OH associated with a sensory neuron membrane protein gene. PMID:20404144

Gould, Fred; Estock, Marie; Hillier, N. Kirk; Powell, Bekah; Groot, Astrid T.; Ward, Catherine M.; Emerson, Jennifer L.; Schal, Coby; Vickers, Neil J.

2010-01-01

383

Role of the Vomeronasal Organ in the Male-Induced Enhancement of Sexual Receptivity in Female Rats  

Microsoft Academic Search

The role of the vomeronasal organ (VNO) in the male-induced enhancement of sexual receptivity in ovariectomized estrogen-primed rats was investigated. Removal of the VNO significantly reduced the enhancement of sexual receptivity following mating, as compared with the sham-operated controls. The sham-operated females exhibited a surge of luteinizing hormone (LH) following mating; however, LH release induced by pairing with males was

Gopalan Rajendren; Carol A. Dudley; Robert L. Moss

1990-01-01

384

Anabolic-androgenic steroids and appetitive sexual behavior in male rats.  

PubMed

Anabolic-androgenic steroids (AAS) increase libido and sexual behavior, but the underlying behavioral mechanisms are unclear. One way AAS may enhance expression of sexual behavior is by increasing the willingness to work for sex. In the present study, sexually-experienced male rats received daily injections of testosterone at supraphysiologic doses (7.5 mg/kg in water with 13% cyclodextrin) or vehicle and were tested for appetitive sexual behavior measured by operant responding for access to an estrous female. Initially, rats were trained in their home cage to respond on a nose-poke under a 10-min fixed-interval schedule for food reward. Once rats achieved stable response rates, the food was replaced by a female, followed by mating for 10 min. There was no effect of testosterone on operant responding for food (28.1 ± 4.4 responses/10 min for testosterone, 30.6 ± 4.3 for vehicle) or sex (35.0 ± 4.0 responses/10 min for testosterone, 37.3 ± 5.2 for vehicle). However, rats made significantly more responses for sex than for food (p < 0.05), and responses for food and sex were positively correlated among individuals (R(2) = 0.6). Additional groups of rats were trained to respond on a lever for the female under a 2nd-order schedule of reinforcement, where 5 responses opened a door to show the female for 5s. After 15 door openings, the male gained access to the female. There was no effect of testosterone on time to complete 75 responses: 38.4 ± 7.8 min for vehicle controls vs 43.3 ± 6.6 min for testosterone-treated rats (p > 0.05). These findings suggest that chronic high-dose testosterone does not enhance appetitive drive for sexual behavior. PMID:25200201

Kim, Jessica Y; Wood, Ruth I

2014-09-01

385

A reevaluation of rice mitochondrial evolution based on the complete sequence of male-fertile and male-sterile mitochondrial genomes.  

PubMed

Plant mitochondrial genomes have features that distinguish them radically from their animal counterparts: a high rate of rearrangement, of uptake and loss of DNA sequences, and an extremely low point mutation rate. Perhaps the most unique structural feature of plant mitochondrial DNAs is the presence of large repeated sequences involved in intramolecular and intermolecular recombination. In addition, rare recombination events can occur across shorter repeats, creating rearrangements that result in aberrant phenotypes, including pollen abortion, which is known as cytoplasmic male sterility (CMS). Using next-generation sequencing, we pyrosequenced two rice (Oryza sativa) mitochondrial genomes that belong to the indica subspecies. One genome is normal, while the other carries the wild abortive-CMS. We find that numerous rearrangements in the rice mitochondrial genome occur even between close cytotypes during rice evolution. Unlike maize (Zea mays), a closely related species also belonging to the grass family, integration of plastid sequences did not play a role in the sequence divergence between rice cytotypes. This study also uncovered an excellent candidate for the wild abortive-CMS-encoding gene; like most of the CMS-associated open reading frames that are known in other species, this candidate was created via a rearrangement, is chimeric in structure, possesses predicted transmembrane domains, and coopted the promoter of a genuine mitochondrial gene. Our data give new insights into rice mitochondrial evolution, correcting previous reports. PMID:22128137

Bentolila, Stéphane; Stefanov, Stefan

2012-02-01

386

Psychosocial profile of male patients presenting with sexual dysfunction in a psychiatric outpatient department in Mumbai, India  

PubMed Central

Introduction: Sexual dysfunction can occur due to biological problems, relationship problems, lack of proper sexual knowledge or a combination of these. India is often known as the land of Kamasutra. But as far as sexuality research is concerned, there is a paucity of relevant data from India. In view of this, we conducted a study to assess the psychosocial profile of males presenting with sexual dysfunction to psychiatry out-patient department of a tertiary medical hospital. Materials and Methods: Hundred consecutive male patients presenting with sexual dysfunction were screened using Arizona Sexual Experiences Scale for clinical sexual dysfunction and after obtaining their informed consent were included in this study. They were assessed using a semi-structured proforma, Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision criteria, Mini-International Neuropsychiatric Interview, and Dyadic Adjustment Scale. Results: Majority of our respondents were in the 18–30 years age group and were married. The main source of sex knowledge for 69% of them was peer group. Age of onset of masturbation was 11–13 years for 43% of them. Premature ejaculation was the most common sexual dysfunction seen in the respondents. Marital discord was seen in significantly lesser number of respondents (32.35%) as also major depressive disorder that was seen in only 16%. Discussion: Premature ejaculation was the most common sexual dysfunction in our sample. Despite the sexual dysfunction, marital discord and depression were seen less commonly in our respondents. PMID:25657457

Kalra, Gurvinder; Kamath, Ravindra; Subramanyam, Alka; Shah, Henal

2015-01-01

387

[Different proteins in mitochondrial proteome of T-type maize cytoplasmic male-sterile line and its maintainer line].  

PubMed

Using T-type maize cytoplasmic male sterile line (T-CMS) and maintainer line as experimental materials, we separated mitochondrial proteins from leaves at seedling, shooting, booting stages, mesocotyl, root and anther at meiosis of pollen mother cell, single-double nucleus stage of pollen grain by two-dimensional electrophoresis with immobilized pH3-10 gradients. About 150 mitochondrial protein spots in seedling leaves, 150 spots in mesocotyls, 150 spots in roots and 100 spots in meiosis anther were observed respectively in this investigation. 6 difference protein spots were identified by MALDI-TOF-MS analysis and NCBI database searching. r40c1 protein was present in mesocotyl of T-CMS and absent in maintainer line. Mature anther-specific protein, DNA-directed RNA polymerase 23kDa subunit, hexokinase II were present and glutathione S-transferase, putative polyprotein were absent in pollen aborted anther of T-CMS. Developmental changes in mitochondrial proteins were found in leaves but no differences were observed in T-CMS and its maintainer line. Obvious differences of mitochondrial proteins were found at single-double nucleus stage anther in T-CMS and maintainer line. These different proteins were considered to be associated to pollen aborted in T-CMS. PMID:18198583

Zhang, Wei Jia; Li, Chun Zheng; Huang, Hai Quan; Wang, Zhen Ying; Peng, Yong Kang

2007-12-01

388

[Cytological observation and DNA methylation analysis of two new cytoplasmic male sterile lines of maize during microsporogenesis].  

PubMed

Cytoplasmic male sterility (CMS) is a widespread phenomenon in higher plants and has been applied in the commercial production of hybrid seeds. Two CMS lines A1 and A2 of maize were obtained previously by a transgenic experiment. In this study, we conducted cytological observation of developmental microspores with CMS line A1, A2 and their maintainer line (18 red) using paraffin section technology. We also analyzed DNA methylation levels at different developmental stages using high performance liquid chromatography (HPLC). Our results showed that the pollen abortion of A1 and A2 mainly happened from the tetrad stage to the middle of mononuclear stage. Another abortive phenomenon found in CMS line A2 occurred at the pollen mother cell stage. The DNA methylation level of leaf increased rapidly from the seedling stage to the shooting stage in 18 red, while it remained constant in A1 and A2. For the tassel, the DNA methylation levels in 18 red increased gradually during the anther development, while a peak of DNA methylation level occurred in A1 and A2 at the tetrad stage, corresponding to the abortion period of microspore. This result suggested that the level of DNA methylation in the tassels is associated with the pollen abortion characteristics in CMS lines. In summary, our results implied a connection between pollen abortion and epigenetic regulation in maize CMS. PMID:25406250

Zhang, Yanhua; Yi, Hongyang; Fang, Ming; Rong, Tingzhao; Cao, Moju

2014-10-01

389

Mitochondrial RNA editing truncates a chimeric open reading frame associated with S male-sterility in maize.  

PubMed

Adjacent mitochondrial open reading frames orf355 and orf77 are associated with S cytoplasmic male sterility (CMS-S) in maize, but the mechanisms leading to collapse of developing CMS-S pollen are unknown. Sequence similarity between orf77 and the mitochondrial ATP synthase subunit 9 (atp9) locus led us to examine RNA editing in orf77 and atp9 transcripts of pre-collapse CMS-S microspores. Editing of atp9 was not influenced by the presence of orf77 transcripts. Sequence analysis of cDNA clones demonstrated that atp9 transcripts are fully edited in CMS-S microspores. Orf77 nucleotides corresponding to edited nucleotides in atp9 were either not edited or edited inefficiently within the context of orf77, perhaps due to limited conservation of flanking sequences between orf77 and atp9. However, eight of ten orf77 cDNA clones carried an unexpected terminating edit that truncated orf77 to predict a peptide of 17 amino acids (ORF17) sharing significant identity with the C-terminal transmembrane domain of the ATP9 protein. PMID:12491012

Gallagher, Larbi J; Betz, Stephanie K; Chase, Christine D

2002-12-01

390

Intraspecific variation in mitochondrial genome sequence, structure, and gene content in Silene vulgaris, an angiosperm with pervasive cytoplasmic male sterility.  

PubMed

In angiosperms, mitochondrial-encoded genes can cause cytoplasmic male sterility (CMS), resulting in the coexistence of female and hermaphroditic individuals (gynodioecy). We compared four complete mitochondrial genomes from the gynodioecious species Silene vulgaris and found unprecedented amounts of intraspecific diversity for plant mitochondrial DNA (mtDNA). Remarkably, only about half of overall sequence content is shared between any pair of genomes. The four mtDNAs range in size from 361 to 429 kb and differ in gene complement, with rpl5 and rps13 being intact in some genomes but absent or pseudogenized in others. The genomes exhibit essentially no conservation of synteny and are highly repetitive, with evidence of reciprocal recombination occurring even across short repeats (< 250 bp). Some mitochondrial genes exhibit atypically high degrees of nucleotide polymorphism, while others are invariant. The genomes also contain a variable number of small autonomously mapping chromosomes, which have only recently been identified in angiosperm mtDNA. Southern blot analysis of one of these chromosomes indicated a complex in vivo structure consisting of both monomeric circles and multimeric forms. We conclude that S. vulgaris harbors an unusually large degree of variation in mtDNA sequence and structure and discuss the extent to which this variation might be related to CMS. PMID:23009072

Sloan, Daniel B; Müller, Karel; McCauley, David E; Taylor, Douglas R; Storchová, Helena

2012-12-01

391

Male Takeovers Are Reproductively Costly to Females in Hamadryas Baboons: A Test of the Sexual Coercion Hypothesis  

PubMed Central

During male takeovers, in addition to fighting off the female’s current mating partner, males may exhibit intense aggressive mate guarding of the newly acquired females. Recent studies indicate that coercive sexual aggression by males is an important strategy through which sexual conflict is expressed. Previous tests of the sexual coercion hypothesis in primates have focused on assessing if female mate choice is effectively reduced by male aggression, however, only one recent study has tested a critical prediction of this hypothesis, namely, that male coercion is reproductively costly to victim females. The present study uses 15 years of data on inter-birth intervals from a large multilevel colony of baboons, mostly Papio h. hamadryas, with a mating system based on harem-defence polygyny to examine if male takeovers impact the length of the abducted females’ inter-birth intervals. Our analysis of 121 inter-birth intervals from 45 adult females indicates that male takeovers are reproductively costly to abducted females as they are associated with an increase in the time they take to conceive and a lengthening of the inter-birth intervals. We discuss how several factors may contribute to this reproductive cost, including male-female sexual conflict, male-male competition, and female-female competition. Our findings suggest that the male’s aggressive herding is the main contributor to the abducted females’ immediate reproductive cost. We argue that although some of the male’s aggressive herding may be driven by male-male competition, nonetheless, it serves a coercive function as it both constrains the female’s mate choice options and hampers her immediate breeding performance. This conclusion is backed up by results obtained in the only other study that has tested the same prediction and which has been carried out in a wild population of hamadryas baboons. PMID:24621865

Polo, Pablo; Hernández-Lloreda, Victoria; Colmenares, Fernando

2014-01-01

392

The C. elegans adult male germline: stem cells and sexual dimorphism  

PubMed Central

The hermaphrodite C. elegans germline has become a classic model for stem cell regulation, but the male C. elegans germline has been largely neglected. This work provides a cellular analysis of the adult C. elegans male germline, focusing on its predicted stem cell region in the distal gonad. The goals of this study were two-fold: to establish the C. elegans male germline as a stem cell model and to identify sex-specific traits of potential relevance to the sperm/oocyte decision. Our results support two major conclusions. First, adult males do indeed possess a population of germline stem cells (GSCs) with properties similar to those of hermaphrodite GSCs (lack of cell cycle quiescence, lack of reproducibly oriented divisions). Second, germ cells in the mitotic region, including those most distal within the niche, exhibit sex-specific behaviors (e.g. cell cycle length) and therefore have acquired sexual identity. Previous studies demonstrated that some germ cells are not committed to a sperm or oocyte cell fate, even in adults. We propose that germ cells can acquire sexual identity without being committed to a sperm or oocyte cell fate. PMID:20659446

Morgan, Dyan E.; Crittenden, Sarah L.; Kimble, Judith

2010-01-01

393

Antiandrogenic pesticides disrupt sexual characteristics in the adult male guppy Poecilia reticulata.  

PubMed Central

Environmental contaminants have been identified as endocrine disruptors through their antiandrogenic activity. Thus, as androgen receptor antagonists, the fungicide vinclozolin and the principal DDT metabolite p,p'-DDE have been demonstrated to induce demasculinization in rats. Whether this is also the case in fish remains to be demonstrated. For a period of 30 days, groups of adult male guppies were exposed to vinclozolin, p,p'-DDE, or the therapeutic antiandrogen flutamide (used as positive control) applied to the fodder at concentrations between 0.1 and 100 microg/g fodder. Subsequently, sexual characteristics of relevance to the male reproductive capacity were measured and compared with untreated control fish. All three chemicals caused profound alterations at increasing levels of biological organization, even in these fully matured males. At the cellular level, the three compounds induced a significant reduction in the number of ejaculated sperm cells. At the organ level, the sexually attractive orange-yellow coloration was reduced in area and discolored, and treated fish also had smaller testes. Further, at the organismal level, computer-aided behavior analyses demonstrated a severe disruption in male courtship behavior. We conclude that this demasculinization is consistent with an antiandrogenic action of vinclozolin and p,p'-DDE and is likely to compromise reproductive capability in this fish. PMID:11675272

Baatrup, E; Junge, M

2001-01-01

394

Antiandrogenic pesticides disrupt sexual characteristics in the adult male guppy Poecilia reticulata.  

PubMed

Environmental contaminants have been identified as endocrine disruptors through their antiandrogenic activity. Thus, as androgen receptor antagonists, the fungicide vinclozolin and the principal DDT metabolite p,p'-DDE have been demonstrated to induce demasculinization in rats. Whether this is also the case in fish remains to be demonstrated. For a period of 30 days, groups of adult male guppies were exposed to vinclozolin, p,p'-DDE, or the therapeutic antiandrogen flutamide (used as positive control) applied to the fodder at concentrations between 0.1 and 100 microg/g fodder. Subsequently, sexual characteristics of relevance to the male reproductive capacity were measured and compared with untreated control fish. All three chemicals caused profound alterations at increasing levels of biological organization, even in these fully matured males. At the cellular level, the three compounds induced a significant reduction in the number of ejaculated sperm cells. At the organ level, the sexually attractive orange-yellow coloration was reduced in area and discolored, and treated fish also had smaller testes. Further, at the organismal level, computer-aided behavior analyses demonstrated a severe disruption in male courtship behavior. We conclude that this demasculinization is consistent with an antiandrogenic action of vinclozolin and p,p'-DDE and is likely to compromise reproductive capability in this fish. PMID:11675272

Baatrup, E; Junge, M

2001-10-01

395

Enhancing mating performance after juvenile hormone treatment in Anastrepha fraterculus (Diptera:Tephritidae): a differential response in males and females acts as a physiological sexing system  

Technology Transfer Automated Retrieval System (TEKTRAN)

Methoprene treatment can reduce the time required for sexual maturation in Anastrepha fraterculus (Diptera: Tephritidae) (Wiedemann) males under laboratory conditions, supporting its use as a treatment for sterile males within the context of the Sterile Insect Technique (SIT). Here we evaluated sexu...

396

Sexual incentive motivation in male rats requires both androgens and estrogens.  

PubMed

In Experiment 1 castrated male rats were implanted with a Silastic capsule containing either E or cholesterol (CHOL) 35 days after castration. They were then tested for sexual incentive motivation and copulatory behaviors every 5th day for 3 weeks. None of the treatments affected sexual incentive motivation. After the last test, all subjects were implanted with DHT-containing Silastic capsules, and tests continued for another 3 weeks. While E+DHT enhanced sexual incentive motivation and copulatory behavior, DHT alone failed to do so. In Experiment 2 the aromatase inhibitor fadrozole (F) was combined with testosterone (T). T restored all behaviors to the level seen in intact rats, and F significantly reduced these effects. In fact, T+F was not different from DHT. T and DHT restored the weight of the prostate and seminal vesicles to levels close to those of intact rats. In Experiment 3 a lower dose of E was employed. Also this dose of E failed to affect sexual incentive motivation while E+DHT restored it to the level of intact animals. Castration enhanced the serum concentrations of LH and FSH. E alone caused a marked reduction, and E+DHT brought both gonadotropins back to the level of intact animals. It was concluded that the doses of E and DHT employed in these experiments were within or close to the physiological range, and that such doses of E completely fail to enhance sexual incentive motivation in castrated animals. DHT has small or no effects. It appears that sexual incentive motivation and copulation require simultaneous stimulation of androgen and estrogen receptors. PMID:19769979

Attila, Martti; Oksala, Riikka; Agmo, Anders

2010-07-01

397

Effects of pesticides used on citrus grown in Spain on the mortality of Ceratitis capitata (Diptera: Tephritidae) Vienna-8 strain sterile males.  

PubMed

Vienna-8 sterile males are currently released in Spain to reduce wild populations of the medfly. Because pesticides are required to maintain populations of some citrus key pests below economic thresholds, there is a need to evaluate the effects of pesticides commonly used in citrus on Vienna-8 males. Males were exposed to differently aged residues of eight pesticides. Abamectin, etofenprox, etoxazole, petroleum spray oil, pymetrozine, and pyriproxyfen resulted harmless to Vienna-8 males. However, fresh residues of chlorpyrifos and spinosad caused high mortalities and had residual effects until 21 and 28 d after treatment, respectively. Following the same method, the lethal effects of chlorpyrifos and spinosad on Ceratitis capitata (Wiedemann) wild-type (wt) males were determined. Surprisingly, these pesticides resulted more toxic for wt than for Vienna-8 males. To determine whether these results could be attributed to intrinsic characteristics of the pesticides or to behavioral differences among Vienna-8 and wt males, a topical application trial was conducted. Vienna-8 males were twice as susceptible to chlorpyrifos as wt males, whereas their susceptibility to spinosad was slightly lower. These results in intrinsic toxicity did not directly explain the differences observed in the extended-laboratory tests with these pesticides. We hypothesize that the lower flight activity ofVienna-8 males relative to wt conspecifics can explain the lower risk observed for Vienna-8 males in the residual tests. Our results should be taken into account when planning area-wide Sterile Insect Technique programs against C. capitata especially in those areas where treatments with chlorpyrifos are approved. PMID:23865187

Juan-Blasco, María; Sabatier-Muñoz, Beatriz; Argilés, Rafael; Jacas, Josep A; Ortego, Félix; Urbaneja, Alberto

2013-06-01

398

Visual method for evaluating the state of sexual development in male grey squirrels (Sciurus carolinensis).  

PubMed

Stages of sexual development in grey squirrels were classified by scoring the presence of periscrotal hair and staining, as well as the position, size and colour of testes, to develop a visual breeding score (VBS). The VBS was a highly significant predictor of the presence and concentration of epididymal spermatozoa, which were produced from 12 months of age. Two classes of producers were identified: 'high' with spermatozoa levels > 10 x 10(6) mL(-1) and 'low' with spermatozoa levels < 10 x 10(6) mL(-1). Sperm motility was variable across all levels of productive males but was generally higher in the 'high' group, indicating that these were 'functional' males. Sexual regression was observed in two autumn periods. The VBS was less effective in determining states of regression and redevelopment; the confidence of classification improved when age class (adult or prepubertal) and date of capture was known. The use of the VBS to classify stages of sexual development in grey squirrels will improve selection of animals for studies of population biology and fertility control, and has potential application in captive breeding studies of rare Sciuridae species. PMID:16554014

Ferryman, Mark; Mayle, Brenda A; Morgan, Geoff W

2006-01-01

399

Male Sterile2 Encodes a Plastid-Localized Fatty Acyl Carrier Protein Reductase Required for Pollen Exine Development in Arabidopsis  

SciTech Connect

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.

Chen, W.; Shanklin, J.; Yu, X.-H.; Zhang, K.; Shi, J.; De Oliveira, S.; Schreiber, L.; Zhang, D.

2011-10-01

400

Effect of Asteracantha longifolia seeds on the sexual behaviour of male rats.  

PubMed

The aim of the present study was to study the effect of seeds of Asteracantha longifolia on the sexual behaviour of male albino rats. The ethanolic extract of seeds of A. longifolia was administered to groups of rats in 100, 150 and 200 mg kg?¹ doses for a period of 28 days, and the action compared with control rats. The changes in body and organ weight, sexual behaviour, histo-architecture and fructose levels of seminal vesicles were observed. The sexual behaviour was assessed by determining parameters such as mount frequency (MF), intromission latency, mount latency (ML) and post-ejaculatory latency. The ethanolic extract exhibited pronounced anabolic effects in treated animals, as evidenced by gains in the body and reproductive organ weights. Increased spermatogenesis due to treatment with extracts was also witnessed in transverse section. The treatment further markedly affected sexual behaviour of the animals, as reflected by the reduction of ML, increase in MF and enhanced attractability towards females. A significant increase in the sperm count as well as fructose levels of seminal vesicles was noted. PMID:19753500

Chauhan, Nagendra S; Sharma, Vikas; Dixit, V K

2011-09-01

401

Socio-Contextual Factors: Moving Beyond Individual Determinants of Sexual Risk Behavior among Gay and Bisexual Adolescent Males  

PubMed Central

This study investigated factors associated with sexual behavior that confers the greatest risk for HIV transmission (i.e., unprotected anal intercourse; UAI) among 52 sexually active gay and bisexual adolescent males in a Midwestern city ages 15-19. A logistic regression model found that ethnicity other than African American, more sexual partners in the past year, greater stigma towards homosexuality, and greater perceived peer sexual norms for risky behavior were significantly associated with UAI (x2=27.96, df=5, p<.001; Nagelkerke R2 = 0.56). Implications for prevention interventions are discussed. PMID:24187600

Torres, Hector; Delonga, Kathryn; Lee, Susanne; Gladstone, Kenneth A.; Barrad, Alex; Huckaby, Scott; Koopman, Cheryl; Gore-Felton, Cheryl

2013-01-01

402

Sequence variation in the androgen receptor gene is not a common determinant of male sexual orientation  

SciTech Connect

To test the hypothesis that DNA sequence variation in the androgen receptor gene plays a causal role in the development of male sexual orientation, the authors have (1) measured the degree of concordance of androgen receptor alleles in 36 pairs of homosexual brothers, (2) compared the lengths of polyglutamine and polyglycine tracts in the amino-terminal domain of the androgen receptor in a sample of 197 homosexual males and 213 unselected subjects, and (3) screened the entire androgen receptor coding region for sequence variation by PCR and denaturing gradient-gel electrophoresis (DGGE) and/or single-strand conformation polymorphism analysis in 20 homosexual males with homosexual or bisexual brothers and one homosexual male with no homosexual brothers, and screened the amino-terminal domain of the receptor for sequence variation in an additional 44 homosexual males, 37 of whom had one or more first- or second-degree male relatives who were either homosexual or bisexual. These analyses show that (1) homosexual brothers are as likely to be discordant as concordant for androgen receptor alleles; (2) there are no large-scale differences between the distributions of polyglycine or polyglutamine tract lengths in the homosexual and control groups; and (3) coding region sequence variation is not commonly found within the androgen receptor gene of homosexual men. The DGGE screen identified two rare amino acid substitutions, ser[sup 205] -to-arg and glu[sup 793]-to-asp, the biological significance of which is unknown. 32 refs., 2 figs., 2 tabs.

Macke, J.P.; Nathans, J.; King, V.L. (Johns Hopkins Univ., Baltimore, MD (United States)); Hu, N.; Hu, S.; Hamer, D.; Bailey, M. (Northwestern Univ., Evanston, IL (United States)); Brown, T. (Johns Hopkins Univ. School of Hygiene and Public Health, Baltimore, MD (United States))

1993-10-01

403

DEVELOPING TRANSGENIC SEXING STRAINS FOR THE RELEASE OF NON-TRANSGENIC STERILE MALE CODLING MOTH, CYDIA POMONELLA  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Sterile Insect Technique (SIT) is currently being used for the control of many agricultural pests including some lepidopteran species. The SIT relies on the rearing and release of large numbers of genetically sterile insects into a wild population. The holokinetic chromosomes of Lepidoptera resp...

404

A 2.5 kb Nco I fragment of Ogura radish mitochondrial DNA is correlated with cytoplasmic male-sterility in Brassica cybrids  

Microsoft Academic Search

Spontaneous reversion to fertility was studied in the progeny of a cytoplasmic male-sterile (CMS) Brassica napus cybrid containing recombinant B. napus\\/Ogura radish mitochondrial genomes. This reversion is concomitant with the disappearance of a 2.5 kb NcoI fragment present in the mitochondrial DNA of Ogura radish, and of CMS cybrids derived from plants carrying Ogura cytoplasm, and absent in the mitochondrial

Sandrine Bonhomme; Françoise Budar; Madina Férault; Georges Pelletier

1991-01-01

405

Expression of the nuclear gene TaFAd is under mitochondrial retrograde regulation in anthers of male sterile wheat plants with timopheevii cytoplasm  

Microsoft Academic Search

Alterations of mitochondrial-encoded subunits of the FoF1-ATP synthase are frequently associated with cytoplasmic male sterility (CMS) in plants; however, little is known about the relationship of the nuclear encoded subunits of this enzyme with CMS. In the present study, the full cDNA of the gene TaFAd that encodes the putative FAd subunit of the FoF1-ATP synthase was isolated from the

Pei Xu; Yuwen Yang; Zhengzhi Zhang; Weihua Chen; Caiqin Zhang; Lixia Zhang; Sixiang Zou; Zhengqiang Ma

2008-01-01

406

Male takeovers are reproductively costly to females in hamadryas baboons: a test of the sexual coercion hypothesis.  

PubMed

During male takeovers, in addition to fighting off the female's current mating partner, males may exhibit intense aggressive mate guarding of the newly acquired females. Recent studies indicate that coercive sexual aggression by males is an important strategy through which sexual conflict is expressed. Previous tests of the sexual coercion hypothesis in primates have focused on assessing if female mate choice is effectively reduced by male aggression, however, only one recent study has tested a critical prediction of this hypothesis, namely, that male coercion is reproductively costly to victim females. The present study uses 15 years of data on inter-birth intervals from a large multilevel colony of baboons, mostly Papio h. hamadryas, with a mating system based on harem-defence polygyny to examine if male takeovers impact the length of the abducted females' inter-birth intervals. Our analysis of 121 inter-birth intervals from 45 adult females indicates that male takeovers are reproductively costly to abducted females as they are associated with an increase in the time they take to conceive and a lengthening of the inter-birth intervals. We discuss how several factors may contribute to this reproductive cost, including male-female sexual conflict, male-male competition, and female-female competition. Our findings suggest that the male's aggressive herding is the main contributor to the abducted females' immediate reproductive cost. We argue that although some of the male's aggressive herding may be driven by male-male competition, nonetheless, it serves a coercive function as it both constrains the female's mate choice options and hampers her immediate breeding performance. This conclusion is backed up by results obtained in the only other study that has tested the same prediction and which has been carried out in a wild population of hamadryas baboons. PMID:24621865

Polo, Pablo; Hernández-Lloreda, Victoria; Colmenares, Fernando

2014-01-01

407

Clark and Hatfield's evidence of women's low receptivity to male strangers' sexual offers revisited.  

PubMed

Although frequently cited, there has been no published scientific replication of Clark and Hatfield's (1989) and Clark's (1990) findings concerning women's low receptivity to male strangers' offers of casual sex. Consistently across three identically designed naturalistic experiments (aggregated N = 144), these authors reported a 0% acceptance rate by women. The present research analyzed an informal "real-life" journalistic project (N= 100) initiated by an Austrian magazine, in which results indicated a 6.1% acceptance rate (95% CI: 2.8-12.6%) for a complete stranger offering women immediate sexual involvement. Various contextual differences, such as setting, subjects' age and attractiveness, and age differences between requestor and receiver, probably contributed to the observed difference in outcome between the journalistic project and the original experiments. The present findings point to the importance of contextual effects in naturalistic investigations of women's receptivity to sexual offers. PMID:16279298

Voracek, Martin; Hofhansl, Angelika; Fisher, Maryanne L

2005-08-01

408

Longitudinal association of HIV conspiracy beliefs with sexual risk among black males living with HIV.  

PubMed

Research is needed to identify culturally relevant factors that may contribute to sexual risk among African Americans. We investigated HIV-specific medical mistrust as one such cultural factor, often exhibited as conspiracy beliefs about HIV (e.g., "AIDS was produced in a government laboratory"), which may be indicative of general suspicion of HIV treatment and prevention messages. Over a 6-month time-period, we measured endorsement of HIV conspiracy beliefs three times and frequency of condom use monthly among 181 HIV-positive African American males. A hierarchical multivariate repeated-measures logistic random effects model indicated that greater belief in HIV conspiracies was associated with a higher likelihood of reporting unprotected intercourse across all time-points. An average of 54% of participants who endorsed conspiracies reported unprotected intercourse, versus 39% who did not endorse conspiracies. Secondary prevention interventions may need to address medical mistrust as a contributor to sexual risk among African Americans living with HIV. PMID:20734227

Bogart, Laura M; Galvan, Frank H; Wagner, Glenn J; Klein, David J

2011-08-01

409

Prenatal letrozole produces a subpopulation of male rats with same-sex preference and arousal as well as female sexual behavior.  

PubMed

Disruption of the sexual differentiation process during critical periods in male rodents produces changes in partner preference and sexual behavior. In this study we used prenatal (gestation days 10-22) letrozole (0.31 and 0.56?g/kg) to inhibit aromatase and alter normal sexual differentiation of males. These animals and control rats (injected with vehicle) were used when adults to study: a) sexual preference (where the experimental male could choose to interact with a receptive female or a sexually experienced male); b) masculine and feminine sexual behaviors (tested in cylindrical arenas); c) non-contact erections when exposed to a female or a male and, d) serum sex steroids and gonadotropin levels. The results showed that 30% of the males treated with letrozole (0.56?g/kg) had same-sex preference, 33% displayed lordosis and 63% showed non-contact erections in the presence of a sexually experienced male. However, 44% of these males also exhibited complete masculine sexual behavior towards receptive females. None of the control males displayed lordosis when mounted by another male and very few (12%) showed non-contact erections when exposed to a sexually experienced male. Similar low percentages were found in those males prenatally treated with the low letrozole dose (0.31?g/kg). No difference was found in the serum levels of testosterone, estradiol, LH and FSH between control and letrozole-treated males regardless of their sexual preference. These results indicate that prenatal selective inhibition of aromatization produces feminization of sexual partner preference, arousal and sexual behavior but does not affect masculine sexual behavior. PMID:25462593

Olvera-Hernández, Sandra; Chavira, Roberto; Fernández-Guasti, Alonso

2015-02-01

410

Transcriptome Sequencing and De Novo Analysis of a Cytoplasmic Male Sterile Line and Its Near-Isogenic Restorer Line in Chili Pepper (Capsicum annuum L.)  

PubMed Central

Background The use of cytoplasmic male sterility (CMS) in F1 hybrid seed production of chili pepper is increasingly popular. However, the molecular mechanisms of cytoplasmic male sterility and fertility restoration remain poorly understood due to limited transcriptomic and genomic data. Therefore, we analyzed the difference between a CMS line 121A and its near-isogenic restorer line 121C in transcriptome level using next generation sequencing technology (NGS), aiming to find out critical genes and pathways associated with the male sterility. Results We generated approximately 53 million sequencing reads and assembled de novo, yielding 85,144 high quality unigenes with an average length of 643 bp. Among these unigenes, 27,191 were identified as putative homologs of annotated sequences in the public protein databases, 4,326 and 7,061 unigenes were found to be highly abundant in lines 121A and 121C, respectively. Many of the differentially expressed unigenes represent a set of potential candidate genes associated with the formation or abortion of pollen. Conclusions Our study profiled anther transcriptomes of a chili pepper CMS line and its restorer line. The results shed the lights on the occurrence and recovery of the disturbances in nuclear-mitochondrial interaction and provide clues for further investigations. PMID:23750245

Wang, Ping-Yong; Fu, Nan; Shen, Huo-Lin

2013-01-01

411

Analysis of a Partial Male-Sterile Mutant of Arabidopsis thaliana Isolated from a Low-Energy Argon Ion Beam Mutagenized Pool  

NASA Astrophysics Data System (ADS)

A screen for Arabidopsis fertility mutants, mutagenized by low-energy argon ion beam, yielded two partial male-sterile mutants tc243-1 and tc243-2 which have similar phenotypes. tc243-2 was investigated in detail. The segregation ratio of the mutant phenotypes in the M2 pools suggested that mutation behaved as single Mendelian recessive mutations. tc243 showed a series of mutant phenotypes, among which partial male-sterile was its striking mutant characteristic. Phenotype analysis indicates that there are four factors leading to male sterility. a. Floral organs normally develop inside the closed bud, but the anther filaments do not elongate sufficiently to position the locules above the stigma at anthesis. b. The anther locules do not dehisce at the time of flower opening (although limited dehiscence occurs later). c. Pollens of mutant plants develop into several types of pollens at the trinucleated stage, as determined by staining with DAPI (4',6-diamidino-2-phenylindole), which shows a variable size, shape and number of nucleus. d. The viability of pollens is lower than that of the wild type on the germination test in vivo and vitro.

Xu, Min; Bian, Po; Wu, Yuejin; Yu, Zengliang

2008-04-01

412

The evaluation of sexual dysfunction in male patients with migraine and tension type headache  

PubMed Central

Background Erectile dysfunction (ED), defined as the inability to achieve or maintain an erection sufficient for satisfactory sexual performance, is a common condition. The psychological, hormonal, neurogenic and arterial pathologies, medications, chronic diseases have been reported in the etiology of the ED. This paper aims to study sexual dysfunction in the male patients with migraine and Tension type headache (TTH). Methods 30 migraine cases (Group M), 31 TTH cases (Group T) and 30 control cases (Group C) were included in the study. Patients were evaluated with medical history, physical examination, body mass index (BMI), Beck Depression Inventory, biochemical analysis and hormone profiles. ED was evaluated via International Index of Erectile Function Scale (IIEF). In statistical analysis, variant analysis, post-hoc tukey test, Pearson correlation test, t-test, and fisher's exact chi-square test were used. Results The patients' mean age was 34.96+/?1.30, 35.54+/?1.52 and 32.26+/?1.38 for group M,T and C, respectively. There was no significant difference between the groups in terms of testosterone levels. Mean IIEF scores was 19.83+/?2.2, 20.39+/?1.35 and 27.83+/?0.34 in groups M,T,C. When M and T groups were compared with group C, there were significant differences, and there was no statistical difference when T and M groups were compared to each other. Beck Depression Scores were not significantly different in groups M, T and C. Conclusion In this study, it was shown that, migraine and TTH affects the sexual functions negatively in male patients. Chronic diseases may cause sexual disorders in patients because of despair, guilt, and fear of death or pain. Our results suggest that, along with the effect of chronic disease and pain, there must be other complicated factors exist causing the development of SD in patients with migraine and TTH. PMID:23718759

2013-01-01

413

Sexual coevolution of spermatophore envelopes and female genital traits in butterflies: Evidence of male coercion?  

PubMed Central

Signa are sclerotized structures located on the inner wall of the corpus bursa of female Lepidoptera whose main function is tearing open spermatophores. The sexually antagonistic coevolution (SAC) hypothesis proposes that the thickness of spermatophore envelopes has driven the evolution of the females signa; this idea is based in the fact that in many lepidopterans female sexual receptivity is at least partially controlled by the volume of ejaculate remaining in the corpus bursa. According to the SAC hypothesis, males evolved thick spermatophore envelopes to delay the post-mating recovery of female sexual receptivity thus reducing sperm competition; in response, females evolved signa for breaking spermatophore envelopes faster, gaining access to the resources contained in them and reducing their intermating intervals; the evolution of signa, in turn, favored the evolution of even thicker spermatophore envelopes, and so on. We tested two predictions of the SAC hypothesis with comparative data on the thickness of spermatophore envelopes of eleven species of Heliconiinae butterflies. The first prediction is that the spermatophore envelopes of polyandrous species with signa will be thicker than those of monandrous species without signa. In agreement with this prediction, we found that the spermatophore envelopes of a polyandrous Heliconius species with signa are thicker than those of two monandrous Heliconius species without signa. The second prediction is that in some species with signa males could enforce monandry in females by evolving “very thick” spermatophore envelopes, in these species we predict that their spermatophore envelopes will be thicker than those of their closer polyandrous relatives with signa. In agreement with this prediction, we found that in two out of three comparisons, spermatophore envelopes of monandrous species with signa have thicker spermatophore envelopes than their closer polyandrous relatives with signa. Thus, our results support the idea that selective pressures arising from sexually antagonistic interactions have been important in the evolution of spermatophore envelopes, female signa and female mating patterns. PMID:24498577

Sánchez, Víctor

2014-01-01

414

Courtship raises male fertilization success through post-mating sexual selection in a spider  

PubMed Central

Courtship is well known for its positive effects on mating success. However, in polyandrous species, sexual selection continues to operate after copulation. Cryptic female choice is expected under unpredictable mating rates in combination with sequential mate encounters. However, there are very few accounts of the effects of courtship on cryptic female choice, and the available evidence is often correlative. Mature Argiope bruennichi females are always receptive and never attack or reject males before mating, although sexual cannibalism after mating occurs regularly. Still, males usually perform an energetic vibratory display prior to copulation. We tested the hypothesis that beneficial effects of courtship arise cryptically, during or after mating, resulting in increased paternity success under polyandry. Manipulating courtship duration experimentally, we found that males that mated without display had a reduced paternity share even though no differences in post-copulatory cannibalism or copulation duration were detected. This suggests that the paternity advantage associated with courtship arose through female-mediated processes after intromission, meeting the definition of cryptic female choice. PMID:19515667

Schneider, Jutta M.; Lesmono, Kristiani

2009-01-01

415

Dextromethorphan-induced psychotoxic behaviors cause sexual dysfunction in male mice via stimulation of ?-1 receptors.  

PubMed

Dextromethorphan (DM) is a well-known antitussive dextrorotatory morphinan. We and others have demonstrated that sigma (?) receptors may be important for DM-mediated neuromodulation. Because an earlier report suggested that DM might affect sexual function and that ? receptor ligands affect signaling pathways in the periphery, we examined whether DM-induced psychotoxic burden affected male reproductive function. We observed that DM had a high affinity at ?-1 receptors in the brain and testis but relatively low affinity at ?-2 receptors. Prolonged treatment with DM resulted in conditioned place preference and hyperlocomotion, followed by an increase in Fos-related antigen expression in the nucleus accumbens in male mice. Simultaneously, DM induced significant reductions in gonadotropin-releasing-hormone immunoreactivity in the hypothalamus. Moreover, we observed that DM induced increased sperm abnormalities and decreased sperm viability and sexual behavior. These phenomena were significantly attenuated by combined treatment with BD1047, a ?-1 receptor antagonist, but not by SM-21, a ?-2 receptor antagonist. Thus, these results suggest that DM psychotoxicity might lead to reproductive stress in male mice by activating ?-1 receptors. PMID:22326744

Nam, Yunsung; Shin, Eun-Joo; Yang, Boo-Keun; Bach, Jae-Hyung; Jeong, Ji Hoon; Chung, Yoon Hee; Park, Eon Sub; Li, Zhengyi; Kim, Kee-Won; Kwon, Young-Bae; Nabeshima, Toshitaka; Kim, Hyoung-Chun

2012-11-01

416

Evidence against a typology: a taxometric analysis of the sexuality of male-to-female transsexuals.  

PubMed

Previous theories and research have suggested there are two distinct types of male-to-female (MF) transsexuals and these types can be distinguished by their sexuality. Using the scales Attraction to Femininity in Males, Core Autogynephilia, Autogynephilic Interpersonal Fanasy, and Attraction to Transgender Fiction as indicator variables, taxometric analysis was applied to an online-recruited sample of 308 MF transsexuals to investigate whether such a distinction is justified. In accordance with previous research findings, MF transsexuals categorized as "nonandrophilic" scored significantly higher on Core Autogynephilia than did those categorized as "androphilic"; they also scored significantly higher on Attraction to Femininity in Males and Attraction to Transgender Fiction. Results of one of the taxometric procedures, L-Mode, gave slightly more support for a dimensional, rather than taxonic (two-type), latent structure. Results of the two other taxometric procedures, MAMBAC and MAXCOV, showed greater support for a dimensional latent structure. Although these results require replication with a more representative sample, they show little support for a taxonomy, which contradicts previous theory that has suggested MF transsexuals' sexuality is typological. PMID:24619650

Veale, Jaimie F

2014-08-01