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Sample records for female fertility asexual

  1. speciation through asexuality in fish: postzygotic reproductive isolation may be completed in spite of fertility of hybrids

    Directory of Open Access Journals (Sweden)

    Karel Janko

    2015-12-01

    Altogether, it appears that initiation of hybrid asexuality and the completion of speciation process through formation of postRIMs are interconnected phenomena. Both processes are linked to the genetic divergence of hybridizing taxa: initially, hybridization between little diverged species leads to recombinant and fertile hybrids allowing intensive gene flow. As the hybridizing taxa continue to diverge, clonally reproducing hybrid females and sterile males become dominant and the gene flow ceases. The speciation may therefore be completed through asexuality of hybrids The work was supported by grant no. 13-12580S provided by the Czech Science Foundation (www.gacr.cz. Further support was provided by the Academy of Sciences of the Czech Republic (www.cas.cz by the grant no. RVO 67985904

  2. Differential evolution of asexual and sexual females in a benign culture environment

    Science.gov (United States)

    Snell, Terry W.

    2013-01-01

    Here we report one of the first investigations of evolvability of lifespan and reproduction in metazoans, examining both extrinsic and intrinsic factors. We tested effects on senescence of an environmental variable (simulated lake hydroperiod, the length of time an aquatic habitat is inundated), female reproductive physiology (asexual females that reproduce by ameiosis, versus sexual females reproducing by meiosis), and time in a benign culture environment (minimal, if any, external mortality factors). To do this we established chemostat cultures of the rotifer Brachionus plicatilis s.s., and maintained the cultures for 385 d. Hydroperiod alone or in interaction with the effects of time in the benign environment (season) or reproductive physiology had no significant effect on the net reproductive rate, generation time, or rate of aging. Yet combining animals from both ephemeral and permanent hydroperiods revealed a 26% increase in asexual female lifespan across seasons (23% decrease in the rate of aging) and a 56% increase in asexual fecundity, suggesting that maintenance in benign laboratory conditions leads to slower aging. The relative stasis of traits for sexual females implies an impact of reproductive physiology on evolvability. In addition we found a positive correlation between fecundity and lifespan, suggesting an absence of trade-offs in life history traits in the benign laboratory environment. PMID:24795527

  3. Fertility Treatments for Females

    Science.gov (United States)

    ... on: The underlying cause of the problem The woman's age Her history of previous pregnancies How long she has had infertility issues The presence or absence of male factor infertility Fertility treatments are most likely to benefit women whose infertility is due to problems with ovulation. ...

  4. Fertility among female hairdressers.

    Science.gov (United States)

    Axmon, Anna; Rylander, Lars; Lillienberg, Linnea; Albin, Maria; Hagmar, Lars

    2006-02-01

    The study investigated whether working as a hairdresser has a negative impact on fertility, measured as time to pregnancy and miscarriage risk. Self-administered questionnaires were sent to 5289 Swedish hairdressers (response rate 50%) and to 5299 age-matched women from the general Swedish population (response rate 54%). Information was collected on time to pregnancy or trying time for women who had tried, but failed, to conceive at the time of the study. The outcome of the pregnancy was determined and categorized as either miscarriage or stillbirth or live birth. The hairdressers were compared with the referents with respect to these two outcomes. Within the hairdresser cohort, the effects of hair treatments, as well as physical workload and stress were investigated. The hairdressers were less successful than the reference cohort in conceiving (fecundability ratio 0.91, 95% confidence interval 0.83-0.99). The effect was reduced after first-month conceptions were excluded, the indication being that the effect may be the result of birth control bias. Within the hairdresser cohort, a self-perceived stressful work situation seemed to prolong the time to pregnancy. No effects were found for the different chemical hair treatments. There was no cohort difference with respect to miscarriage risk (odds ratio 1.12, 95% confidence interval 0.88-1.42), but miscarriage risks were increased for most of the hair treatments and for self-perceived stressful work situations. However, none of these effects were statistically significant. The present study indicates a negative impact on time to pregnancy and miscarriage risk for working as a hairdresser".

  5. Female relative wages, household specialization and fertility

    OpenAIRE

    Siegel, Christian

    2017-01-01

    Falling fertility rates have often been linked to rising female wages. However, over the last 40 years the US total fertility rate has been rather stable while female wages have continued to grow. Over the same period, women's hours spent on housework have declined, but men's have increased. I propose a model in which households are not perfectly specialized, but both men and women contribute to home production. As the gender wage gap narrows, the time allocations of men and women converge, a...

  6. Fertility in female childhood cancer survivors

    DEFF Research Database (Denmark)

    De Bruin, Marie L; Van Dulmen-den Broeder, Eline; Van den Berg, Marleen H

    2009-01-01

    chemotherapy and radiotherapy may have an adverse effect on ovarian function, ovarian reserve and uterine function, clinically leading to sub-fertility, infertility, premature menopause and/or adverse pregnancy outcomes. Here we will first address normal female fertility and methods to detect decreased...... fertility. Hence we will focus on direct effects as well as late fertility-related adverse effects caused by chemotherapy and radiotherapy, and we will conclude with a summary of current options for fertility preservation in female childhood cancer survivors.......Advances in childhood cancer treatment over the past decades have significantly improved survival, resulting in a rapidly enlarging group of childhood cancer survivors. There is much concern, however, about the effects of treatment on reproductive potential. In women there is evidence that both...

  7. Female employment reduces fertility in rural Senegal.

    Science.gov (United States)

    Van den Broeck, Goedele; Maertens, Miet

    2015-01-01

    Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities.

  8. Female employment reduces fertility in rural Senegal.

    Directory of Open Access Journals (Sweden)

    Goedele Van den Broeck

    Full Text Available Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities.

  9. Fertility Effects on Female Labor Supply

    DEFF Research Database (Denmark)

    Lundborg, Petter; Plug, Erik; Rasmussen, Astrid Würtz

    This paper introduces a new IV strategy based on IVF induced fertility variation in childless families to estimate the causal effect of having children on female labor supply using IVF treated women in Denmark. Because observed chances of IVF success do not depend on labor market histories, IVF...... treatment success provides a plausible instrument for childbearing. Our IV estimates indicate that fertility effects are: (a) negative, large and long lasting; (b) much stronger at the extensive margin than at the intensive margin, and (c) similar for mothers, not treated with IVF, which suggests that IVF...

  10. Fertility and Childbearing Among American Female Physicians.

    Science.gov (United States)

    Stentz, Natalie Clark; Griffith, Kent A; Perkins, Elena; Jones, Rochelle DeCastro; Jagsi, Reshma

    2016-10-01

    Female physicians may experience unique challenges regarding fertility and family planning. We sought to determine childbearing patterns and decision-making among American female physicians. In 2012-2013, we surveyed a random sample of 600 female physicians who graduated medical school between 1995 and 2000. Primary outcome measures included fertility and childbearing history, reflections regarding decision-making, perceptions of workplace support, and estimations of childbearing potential. Response rate was 54.5% (327/600). A majority (82.0%) of the sample were parents, 77.4% had biological children with an average of 2.3 children. Average age at medical school graduation was 27.5 years, at completion of training (completion of medical school, residency, and/or fellowship) was 31.6 years, and at first pregnancy was 30.4 years. Nearly one quarter (24.1%) of respondents who had attempted conception were diagnosed with infertility, with an average age at diagnosis of 33.7 years. Among those with infertility, 29.3% reported diminished ovarian reserve. When asked what they would do differently in retrospect, most respondents (56.8%) would do nothing differently regarding fertility/conception/childbearing, 28.6% would have attempted conception earlier, 17.1% would have gone into a different specialty, and 7.0% would have used cryopreservation to extend fertility. Fewer of those whose first pregnancy was in medical school perceived substantial workplace support (68.2%) than those whose first pregnancies followed training (88.6%). A substantial proportion of female physicians have faced infertility or have regrets about family planning decisions and career decision-making. Combining a medical career with motherhood continues to pose challenges, meriting further investigation and targeted support.

  11. Female Employment and Fertility in Rural China

    OpenAIRE

    Fang, Hai; Eggleston, Karen N.; Rizzo, John A.; Zeckhauser, Richard Jay

    2010-01-01

    Data on 2,288 married women from the 2006 China Health and Nutrition Survey are deployed to study how off-farm female employment affects fertility. Such employment reduces a married woman’s actual number of children by 0.64, her preferred number by 0.48, and her probability of having more than one child by 54.8 percent. Causality flows in both directions; hence, we use well validated instrumental variables to estimate employment status. China has deep concerns with both female employment an...

  12. Fertility in female survivors of Hodgkin's lymphoma

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    Irene Biasoli

    2012-01-01

    Full Text Available Currently, Hodgkin's lymphoma is one of the most curable types of cancer. Patients are often young and so the long-term morbidities of treatment have become of increasing concern. Among these, infertility is one of the most challenging consequences for patients in reproductive age. Premature ovarian failure in premenopausal women is a serious long-term sequel of the toxicity of chemotherapy. The main consequence of this syndrome is infertility, but women also present other symptoms related to estrogen deprivation. Different rates of impaired gonadal function are reported, depending on the patient's age, stage of disease, dose and intensity of chemotherapy and the use of radiation therapy. The most established strategy in female infertility is cryopreservation of embryos after in vitro fertilization. Additionally, the use of oral contraceptives or gonadotropinreleasing hormone analogs (GnRH-a during treatment is under study. This review will provide a general overview of the main studies conducted to evaluate the infertility rate among female Hodgkin's lymphoma survivors and risk factors associated to treatment, different end-point definitions for evaluating fertility and also a brief description of the available strategies for fertility preservation.

  13. Jobs and Kids: Female Employment and Fertility in Rural China

    OpenAIRE

    Hai Fang; Karen N. Eggleston; John A. Rizzo; Richard J. Zeckhauser

    2010-01-01

    Data on 2,355 married women from the 2006 China Health and Nutrition Survey are used to study how female employment affects fertility in China. China has deep concerns with both population size and female employment, so the relationship between the two should be better understood. Causality flows in both directions. A conceptual model shows how employment prospects affect fertility. Then a well-validated instrumental variable isolates this effect. Female employment reduces a married woman's p...

  14. Jobs and kids: Female employment and fertility in China

    OpenAIRE

    Fang, Hai; Eggleston, Karen N.; Rizzo, John A.; Zeckhauser, Richard J.

    2013-01-01

    Data on 2,355 married women from the 2006 China Health and Nutrition Survey are used to study how female employment affects fertility in China. China has deep concerns with both population size and female employment, so the relationship between the two should be better understood. Causality flows in both directions. A conceptual model shows how employment prospects affect fertility. Then a well-validated instrumental variable isolates this effect. Female employment reduces a married woman’s...

  15. Female labour force participation and fertility.

    Science.gov (United States)

    Concepcion, M B

    1974-01-01

    The levels of labor force participation by women in selected Asian countries were recorded in a series of censuses taken over a period of years. These levels were less influenced than male employment levels by economic conditions and more influenced by cultural traits of the country. Postwar trends seem to have fallen in Korea, risen in Singapore and the Philippines, and remained steady in Japan, Malaya, and Thailand. The limitations of these data are mentioned. In Thailand and West Malaysia greater percentages of women worked in agricultural than non-agricultural employment; in the Philippines, where women did not work so much in agricultural pursuits, their jobs were still in traditional rather than in development industries. In the cities of Bangkok, Manila, and Kuala Lumpur, fertility was lower for working than for non-working women. In rural agricultural areas, the fertility of working women was minimally higher, probably due to economic need of lar ger families. It is concluded that urban life separates the employment and the family roles of working women, leading to lowered fertility; this does not occur in rural areas. The creation of new roles for women alternative or supplementary to marriage and motherhood would result in lowered fertility. In high fertility Asian countries, policies directed toward greater participation of women in non-agricultural work and great er exposure to an urban lifestyle might achieve fertility reductions.

  16. “I am no male or female or any other, I have no sex”: a case report on asexuality

    Directory of Open Access Journals (Sweden)

    Niranjan Hebbar YR

    2017-12-01

    Full Text Available A rather less investigated field of sexual orientation, “asexuality” is spread out within the dimensions on lack of sexual attraction or interest on sexual behaviour, and on self-identification issues, or in combination of these. As sex is considered to be one of the basic instincts of human beings which has been followed since centuries, growing reports of asexuality is a concern against the evolution theory. There is lack of studies to assess the exact prevalence of asexuality in Indian setup. Here we are presenting a case of a 20-year-old male, who presented with self-identity issues with no preference for any particular sexual identity.

  17. Female Employment and Fertility: Further Investigation of an Ambivalent Association

    OpenAIRE

    Zeba A. sathar; Shahnaz Kazi

    1989-01-01

    This study of the relationship between female employment and fertility is based on a survey of 1000 ever-married women in Karachi. A distinct pattern of differentials in actual performance and in desired fertility is observed across working and non-working women. Working women are not a homogeneous group, and the differences across six broad occupational groups of working women are more marked than those between working and non-working women. Women in higher status occupations marry much late...

  18. Female Labor Supply and Fertility. Causal Evidence for Latin America

    OpenAIRE

    Darío Tortarolo

    2014-01-01

    In this paper I study the causal relationship between fertility and female labor supply using census data from 14 Latin American countries and the U.S. over the span of three decades (1980, 1990 and 2000). Parental preferences for a gender-balanced family (mixed-sex children) is exploited as a source of exogenous variation in fertility. Although OLS estimates suggest a statistically signi cant negative relationship in the 39 censuses used, instrumental variables approach fails to identify a c...

  19. Fertility in female reindeer: the effects of nutrition and growth

    OpenAIRE

    N. J.C. Tyler

    1987-01-01

    Pregnancy rates in juvenile reindeer (Rangifer tarandus) vary considerably both within and between flocks. This potentially has considerable economic significance for reindeer husbandry. This paper discusses the influence of nutrition and growth on fertility in female reindeer using examples taken from the literature. Fertility in reindeer is related to body weight, like in many other mammals, but the relationship is not invariant. Weight-specific pregnancy rates appear to be density dependen...

  20. Fertility and the changing female educational attainment in Croatia

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    Čipin Ivan

    2016-01-01

    Full Text Available This paper investigates the aggregate relationship between cohort fertility and female educational attainment in Croatia. Numerous demographic studies have examined the link between fertility and the level of education. However, newer research indicates that the field of education might also play a role when trying to explain fertility behavior. We contribute to existing literature on macro-level factors related to reproductive outcomes by considering both the level and field of education as possible sources of cohort fertility differentials. The main goal of the present study is to assess the effect of structural changes in educational attainment on cohort fertility decline by means of demographic decomposition techniques. Our analysis is based on detailed 2011 Census data, which provide information on the number of livebirths by mother’s year of birth, birth order, marital status and educational attainment (i.e. the level and field of education. The results of our decomposition analyses reveal the dominance of the structural effect in explaining the overall completed fertility decline in Croatia. We assumed that the changing distribution of women by field of education at least partially accounts for the observed patterns in completed fertility but found no strong evidence in support of the outlined hypothesis.

  1. Genetic correlations between female fertility and production traits in ...

    African Journals Online (AJOL)

    South African Journal of Animal Science. Journal Home ... Female fertility is increasingly gaining importance in national dairy cattle breeding objectives worldwide. In South Africa ... http://dx.doi.org/10.4314/sajas.v37i3.4090 · AJOL African ...

  2. Household consumption, female employment and fertility decisions; A microeconometric analysis

    NARCIS (Netherlands)

    Kalwij, A.S.

    1999-01-01

    This thesis is mainly concerned with a simultaneous analysis of the economic determinants of female employment and fertility decisions on a household level in the Netherlands. In particular, this thesis is interested in the role of the employment decisions of women in the observed behavior that

  3. Sexual versus Asexual Reproduction: Distinct Outcomes in Relative Abundance of Parthenogenetic Mealybugs following Recent Colonization.

    Science.gov (United States)

    Tabata, Jun; Ichiki, Ryoko T; Tanaka, Hirotaka; Kageyama, Daisuke

    2016-01-01

    Asexual reproduction, including parthenogenesis in which embryos develop within a female without fertilization, is assumed to confer advantages over sexual reproduction, which includes a "cost of males." Sexual reproduction largely predominates in animals, however, indicating that this cost is outweighed by the genetic and/or ecological benefits of sexuality, including the acquisition of advantageous mutations occurring in different individuals and the elimination of deleterious mutations. But the evolution of sexual reproduction remains unclear, because we have limited examples that demonstrate the relative success of sexual lineages in the face of competition from asexual lineages in the same environment. Here we investigated a sympatric occurrence of sexual and asexual reproduction in the pineapple mealybug, Dysmicoccus brevipes. This pest invaded southwestern Japan, including Okinawa and Ishigaki Islands, in the 1930s in association with imported pineapple plants. Our recent censuses demonstrated that on Okinawa sexually reproducing individuals can coexist with and even dominate asexual individuals in the presence of habitat and resource competition, which is considered to be severe for this nearly immobile insect. Molecular phylogeny based on partial DNA sequences in the mitochondrial and nuclear genomes, as well as the endosymbiotic bacterial genome, revealed that the asexual lineage diverged from a common sexual ancestor in the relatively recent past. In contrast, only the asexual lineage exhibiting obligate apomictic thelytoky was discovered on Ishigaki. Co-existence of the two lineages cannot be explained by the results of laboratory experiments, which showed that the intrinsic rate of increase in the sexual lineage was not obviously superior to that of the asexual lineage. Differences in biotic and/or abiotic selective forces operating on the two islands might be the cause of this discrepancy. This biological system offers a unique opportunity to assess

  4. Speciation and reduced hybrid female fertility in house mice.

    Science.gov (United States)

    Suzuki, Taichi A; Nachman, Michael W

    2015-09-01

    In mammals, intrinsic postzygotic isolation has been well studied in males but has been less studied in females, despite the fact that female gametogenesis and pregnancy provide arenas for hybrid sterility or inviability that are absent in males. Here, we asked whether inviability or sterility is observed in female hybrids of Mus musculus domesticus and M. m. musculus, taxa which hybridize in nature and for which male sterility has been well characterized. We looked for parent-of-origin growth phenotypes by measuring adult body weights in F1 hybrids. We evaluated hybrid female fertility by crossing F1 females to a tester male and comparing multiple reproductive parameters between intrasubspecific controls and intersubspecific hybrids. Hybrid females showed no evidence of parent-of-origin overgrowth or undergrowth, providing no evidence for reduced viability. However, hybrid females had smaller litter sizes, reduced embryo survival, fewer ovulations, and fewer small follicles relative to controls. Significant variation in reproductive parameters was seen among different hybrid genotypes, suggesting that hybrid incompatibilities are polymorphic within subspecies. Differences in reproductive phenotypes in reciprocal genotypes were observed and are consistent with cyto-nuclear incompatibilities or incompatibilities involving genomic imprinting. These findings highlight the potential importance of reduced hybrid female fertility in the early stages of speciation. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  5. Asexual reproduction induces a rapid and permanent loss of sexual reproduction capacity in the rice fungal pathogen Magnaporthe oryzae: results of in vitro experimental evolution assays

    Directory of Open Access Journals (Sweden)

    Saleh Dounia

    2012-03-01

    Full Text Available Abstract Background Sexual reproduction is common in eukaryotic microorganisms, with few species reproducing exclusively asexually. However, in some organisms, such as fungi, asexual reproduction alternates with episodic sexual reproduction events. Fungi are thus appropriate organisms for studies of the reasons for the selection of sexuality or clonality and of the mechanisms underlying this selection. Magnaporthe oryzae, an Ascomycete causing blast disease on rice, reproduces mostly asexually in natura. Sexual reproduction is possible in vitro and requires (i two strains of opposite mating types including (ii at least one female-fertile strain (i.e. a strain able to produce perithecia, the female organs in which meiosis occurs. Female-fertile strains are found only in limited areas of Asia, in which evidence for contemporary recombination has recently been obtained. We induced the forced evolution of four Chinese female-fertile strains in vitro by the weekly transfer of asexual spores (conidia between Petri dishes. We aimed to determine whether female fertility was rapidly lost in the absence of sexual reproduction and whether this loss was controlled genetically or epigenetically. Results All the strains became female-sterile after 10 to 19 rounds of selection under asexual conditions. As no single-spore isolation was carried out, the observed decrease in the production of perithecia reflected the emergence and the invasion of female-sterile mutants. The female-sterile phenotype segregated in the offspring of crosses between female-sterile evolved strains and female-fertile wild-type strains. This segregation was maintained in the second generation in backcrosses. Female-sterile evolved strains were subjected to several stresses, but none induced the restoration of female fertility. This loss of fertility was therefore probably due to genetic rather than epigenetic mechanisms. In competition experiments, female-sterile mutants produced similar

  6. Crybb2 deficiency impairs fertility in female mice

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Qian [Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Sun, Li-Li [Aviation Medical Evaluation and Training Center of Airforce in Dalian, Dalian, Liaoning Province 116013 (China); Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Xiang, Fen-Fen [Department of Laboratory Medicine, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200062 (China); Gao, Li [Department of Pathology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Jia, Yin; Zhang, Jian-Rong; Tao, Hai-Bo [Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Zhang, Jun-Jie, E-mail: zhangjj910@163.com [Department of Obstetrics and Gynecology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Li, Wen-Jie, E-mail: wenjieli@pku.org.cn [Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China)

    2014-10-10

    Highlights: • Crybb2 deletion impaired female fertility. • Crybb2 deletion dramatically affected the production of reproduction-related hormones and hormone response. • Crybb2 deletion impaired follicular development and inhibited the proliferation of granulosa cells. • Crybb2 deletion promoted follicular atresia and apoptosis in granulosa cells. - Abstract: Beta-B2-crystallin (CRYBB2), encoded by Crybb2 gene, is a major protein in the mammalian eye lens that plays an important role in maintaining the transparency of the ocular lens. However, CRYBB2 also plays important roles in many extra-lenticular tissues and organs such as the retina, brain and testis. Our previous studies demonstrated that male Crybb2 deficient (Crybb2{sup −/−}) mice have reduced fertility compared with wild-type (WT) mice, while female Crybb2{sup −/−} mice exhibited reduced ovary weights and shorter estrous cycle percentages. Here we specifically investigated the role of CRYBB2 in the female reproductive system. Our studies revealed that ovaries from female Crybb2{sup −/−} mice exhibited significantly reduced numbers of primordial, secondary and pre-ovulatory follicles when compared with WT mice, while the rate of atretic follicles was also increased. Additionally, fewer eggs were collected from the oviduct of Crybb2{sup −/−} female mice after superovulation. Estrogen levels were higher in the metestrus and diestrus cycles of female Crybb2{sup −/−} mice, while progesterone levels were lower in diestrus cycles. Furthermore, the expression of survival and cell cycle genes, Bcl-2, Cdk4 and Ccnd2, were significantly decreased in granulosa cells isolated from female Crybb2{sup −/−} mice, consistent with the predominant expression of CRYBB2 in ovarian granulosa cells. Our results reveal a critical role for CRYBB2 in female fertility and specific effects on the proliferation and survival status of ovarian granulosa cells.

  7. Crybb2 deficiency impairs fertility in female mice

    International Nuclear Information System (INIS)

    Gao, Qian; Sun, Li-Li; Xiang, Fen-Fen; Gao, Li; Jia, Yin; Zhang, Jian-Rong; Tao, Hai-Bo; Zhang, Jun-Jie; Li, Wen-Jie

    2014-01-01

    Highlights: • Crybb2 deletion impaired female fertility. • Crybb2 deletion dramatically affected the production of reproduction-related hormones and hormone response. • Crybb2 deletion impaired follicular development and inhibited the proliferation of granulosa cells. • Crybb2 deletion promoted follicular atresia and apoptosis in granulosa cells. - Abstract: Beta-B2-crystallin (CRYBB2), encoded by Crybb2 gene, is a major protein in the mammalian eye lens that plays an important role in maintaining the transparency of the ocular lens. However, CRYBB2 also plays important roles in many extra-lenticular tissues and organs such as the retina, brain and testis. Our previous studies demonstrated that male Crybb2 deficient (Crybb2 −/− ) mice have reduced fertility compared with wild-type (WT) mice, while female Crybb2 −/− mice exhibited reduced ovary weights and shorter estrous cycle percentages. Here we specifically investigated the role of CRYBB2 in the female reproductive system. Our studies revealed that ovaries from female Crybb2 −/− mice exhibited significantly reduced numbers of primordial, secondary and pre-ovulatory follicles when compared with WT mice, while the rate of atretic follicles was also increased. Additionally, fewer eggs were collected from the oviduct of Crybb2 −/− female mice after superovulation. Estrogen levels were higher in the metestrus and diestrus cycles of female Crybb2 −/− mice, while progesterone levels were lower in diestrus cycles. Furthermore, the expression of survival and cell cycle genes, Bcl-2, Cdk4 and Ccnd2, were significantly decreased in granulosa cells isolated from female Crybb2 −/− mice, consistent with the predominant expression of CRYBB2 in ovarian granulosa cells. Our results reveal a critical role for CRYBB2 in female fertility and specific effects on the proliferation and survival status of ovarian granulosa cells

  8. Tristania Sumatrana Effect On Female Mus Musculus Fertility

    Science.gov (United States)

    Syamsurizal, S.

    2018-04-01

    The use of traditional medicinal plants are generally based on empirical experience, therefore it is necessary scientific approach in order to bring traditional medicine into medical practice and the formal health services. Tristania sumatrana Miq. is one of the traditional medicinal plants are often used as a contraceptive for women in West Sumatra Tristania sumatrana Miq. extract can prolong the estrous cycle in mice to eleven days. This study aimed to influence Tristania sumatrana Miq. extract treatment on fertility of female mice. Experiments conducted a randomized block design 5x2. Five dose groups: control with no treatment, placebo, treatment with doses of 600, 900 and 1200 mg/kgbw and the old two treatment groups: 10 and 20 days. Fertility parameters studied were ovarian weight follicle Graaf number, the corpus luteum and fetal life. The research proves of Tristania sumatrana Miq. extract treatment causes a decrease very significantly the ovarian weight (treatment of 900 mg/kgbw for 10 days), follicles Graaf number (900 mg/kgbw for 20 days), the corpus luteum (600 mg/kgbw for 10 days) and live fetuses (900 mg/kgbw for 10 days). Tristania sumatrana Miq. extract treatment can lead to decreased fertility of female mice.

  9. Female labour force participation, fertility and public policy in Sweden.

    Science.gov (United States)

    Sundstrom, M; Stafford, F P

    1992-01-01

    2nd only to Ireland in total fertility, Sweden has the highest total fertility (TFR) and female labor force participation rates (FLFPR) among European countries in the late 1980s and early 1990s. 1988 TFR and FLFPR were 1.96 and 80.1%, respectively. This paper considers the role of public policy in creating this unique trend, with particular focus on family leave policy. In 1974, Sweden became the 1st country to allow leave to both parents following childbirth. By 1990, leave duration had grown from an initial 6-month period to 15 months. In addition, subsidized day care, flexible working hours, and economic support to families with children is provided in the context of a family-supportive tax structure. While generous, benefits are related to work and income history. Labor income is replaced at 90% of gross earnings, while the unemployed receive only minimal taxable flat payments. Benefits overall are paid from general taxes. Given that benefits reflect job history and income, and income level tends to rise fastest in the initial stages of employment, women in Sweden postpone childbirth in order to realize wage increases and greater job standing over the short- to medium-terms. In sum, Sweden's policies stimulate both fertility and women's paid work by reducing the costs of having children while requiring parents to be employed to receive full benefits. This paper further reviews the development of parental leave and related policies and compares Swedish fertility, female labor force participation, and parental leave benefits to those of countries in the European Community.

  10. Female parthenogenetic apomixis and androsporogenetic parthenogenesis in embryonal cells of Araucaria angustifolia: interpolation of progenesis and asexual heterospory in an artificial sporangium.

    Science.gov (United States)

    Durzan, Don J

    2012-09-01

    Cell fate, development timing and occurrence of reproductive versus apomictic development in gymnosperms are shown to be influenced by culture conditions in vitro. In this study, female parthenogenetic apomixis (fPA), androsporogenetic parthenogenesis (mAP) and progenesis were demonstrated using embryonal initials of Araucaria angustifolia in scaled-up cell suspensions passing through a single-cell bottleneck in darkness and in an artificial sporangium (AS). Expression was based on defined nutrition, hormones and feedforward-adaptive feedback process controls at 23-25 °C and in darkness. In fPA, the nucleus of an embryonal initial undergoes endomitosis and amitosis, forming a diploid egg-equivalent and an apoptotic ventral canal nucleus in a transdifferentiated archegonial tube. Discharge of egg-equivalent cells as parthenospores and their dispersal into the aqueous culture medium were followed by free-nuclear conifer-type proembryogenesis. This replaced the plesiomorphic and central features of proembryogenesis in Araucariaceae. Protoplasmic fusions of embryonal initials were used to reconstruct heterokaryotic expressions of fPA in multiwell plates. In mAP, restitutional meiosis (automixis) was responsible for androsporogenesis and the discharge of monads, dyads, tetrads and polyads. In a display of progenesis, reproductive development was brought to an earlier ontogenetic stage and expressed by embryonal initials. Colchicine increased polyploidy, but androspore formation became aberrant and fragmented. Aberrant automixis led to the formation of chromosomal bouquets, which contributed to genomic silencing in embryonal initials, cytomixis and the formation of pycnotic micronucleated cells. Dispersal of female and male parthenospores displayed heteromorphic asexual heterospory in an aqueous environment.

  11. Female fertility preservation in the pediatric and adolescent cancer patient population.

    Science.gov (United States)

    Algarroba, Gabriela N; Sanfilippo, Joseph S; Valli-Pulaski, Hanna

    2018-04-01

    The 5-year survival rate for childhood cancer is over 80%, thereby increasing the number of young women facing infertility in the future because of the gonadotoxic effects of chemotherapy and radiation. The gonadotoxic effects of childhood cancer treatment vary by the radiation regimen and the chemotherapeutic drugs utilized. Although the American Society of Clinical Oncology guidelines recommend fertility preservation for all patients, there are several barriers and ethical considerations to fertility preservation in the pediatric and adolescent female population. Additionally, the fertility preservation methods for pre- and postpubertal females differ, with only experimental methods available for prepubertal females. We will review the risk of chemotherapy and radiation on female fertility, the approach to fertility preservation in the pediatric and adolescent female population, methods of fertility preservation for both pre- and postpubertal females, barriers to fertility preservation, cost, and psychological and ethical considerations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Oxidative stress and antioxidants: exposure and impact on female fertility

    Science.gov (United States)

    Ruder, Elizabeth H.; Hartman, Terryl J.; Blumberg, Jeffrey; Goldman, Marlene B.

    2009-01-01

    Background Reproductive failure is a significant public health concern. Although relatively little is known about factors affecting fertility and early pregnancy loss, a growing body of literature suggests that environmental and lifestyle factors play an important role. There is sufficient evidence to hypothesize that diet, particularly its constituent antioxidants, and oxidative stress (OS) may influence the timing and maintenance of a viable pregnancy. We hypothesize that conditions leading to OS in the female affect time-to-pregnancy and early pregnancy loss. Methods We review the epidemiology of female infertility related to antioxidant defenses and oxidation and examine potential sources of OS from the ovarian germ cell through the stages of human pregnancy and pregnancy complications related to infertility. Articles were identified through a search of the PubMed database. Results Female OS is a likely mediator of conception and threshold levels for OS exist, dependent on anatomic location and stage of preconception. Conclusions Prospective pregnancy studies with dietary assessment and collection of biological samples prior to conception with endpoints of time-to-pregnancy and early pregnancy loss are needed. PMID:18535004

  13. Fertility and sexual function in female Hodgkin lymphoma survivors of reproductive age

    NARCIS (Netherlands)

    Eeltink, C.M.; Incrocci, L.; Witte, B.I.; Meurs, S.; Visser, O.; Huijgens, P.C.; de Leeuw, I.M.

    2013-01-01

    Aims and objectives: To assess the perceived fertility status and to determine the association between perceived fertility status and sexual function, as reported by young female Hodgkin lymphoma survivors. Background: Young female Hodgkin lymphoma survivors are at risk of infertility and impaired

  14. A Comparison of In Vitro and In Vivo Asexual Embryogenesis

    NARCIS (Netherlands)

    Hand, Melanie; Vries, de S.C.; Koltunow, Anna

    2016-01-01

    In plants, embryogenesis generally occurs through the sexual process of double fertilization, which involves a haploid sperm cell fusing with a haploid egg cell to ultimately give rise to a diploid embryo. Embryogenesis can also occur asexually in the absence of fertilization, both in vitro and in

  15. Fertility in female reindeer: the effects of nutrition and growth

    Directory of Open Access Journals (Sweden)

    N. J.C. Tyler

    1987-06-01

    Full Text Available Pregnancy rates in juvenile reindeer (Rangifer tarandus vary considerably both within and between flocks. This potentially has considerable economic significance for reindeer husbandry. This paper discusses the influence of nutrition and growth on fertility in female reindeer using examples taken from the literature. Fertility in reindeer is related to body weight, like in many other mammals, but the relationship is not invariant. Weight-specific pregnancy rates appear to be density dependent in juvenile reindeer although not in adults. This strongly suggests that nutrition has an important influence on fertility in juveniles.Fruktbarhet hos simler: effekter av ernæring og vekst.Abstract in Norwegian / Sammendrag: Drektighetsprosenten i ungrein varierer sterkt fra individ til individ og fra flokk til flokk. En høy fruktbarhet i reinflokken er selve grunnlaget for en vellykket reindrift. Overraskende er det derfor at man vet lite om hvilke faktorer som bestemmer om rein skal bli drektig eller ikke. I denne artikkelen blir effekten av ernæring på reinsimlenes fruktbarhet diskutert. Undersøkelser indikerer at rein er som andre pattedyr, der fruktbarheten er relatert til kroppsvekten. Forholdet mellom reinens kroppsvekt og fruktbarhet varierer likevel sterkt. Mye tyder på at drektighetsprosenten i ungrein er avhengig av reintettheten. Dette indikerer at ernæringen er en viktig faktor når det gjelder fruktbarhet i ungrein. Vekt-spesifikk fruktbarhet kan derfor være en brukbar indikator for reinflokkens fortilgang. I prinsippet vil slike fruktbarhetsundersøkelser gi et en brukbar indikator for reinflokkens fortilgang. I prinsippet vil slike fruktbarhetsundersøkelser gi et tidlig varsel om reintallet er for høyt i forhold til beitegrunnlaget før en markert nedgang i slaktevekten observeres.Ravitsemustilan ja kasvun vaikutus vaatimien hedelmållisyyteen.Abstract in Finnish / Yhteenveto: Nuorten porojen hedelmåliisyys vaihtelee suuresti

  16. Male chimpanzees' grooming rates vary by female age, parity, and fertility status

    DEFF Research Database (Denmark)

    Proctor, Darby P; Lambeth, Susan P; Schapiro, Steve

    2011-01-01

    , should show little or no preference when choosing mating partners (e.g. should mate indiscriminately). To determine if the preferences indicated by copulations appear in other contexts as well as how they interact, we examined how male chimpanzees' grooming patterns varied amongst females. We found...... that males' preferences were based on interactions among females' fertility status, age, and parity. First, grooming increased with increasing female parity. We further found an effect of the estrous cycle on grooming; when females were at the lowest point of their cycle, males preferentially groomed parous...... females at peak reproductive age, but during maximal tumescence, males preferred the oldest multiparous females. Nulliparous females received relatively little grooming regardless of age or fertility. Thus, male chimpanzees apparently chose grooming partners based on both female's experience and fertility...

  17. Asexual sporulation facilitates adaptation

    NARCIS (Netherlands)

    Zhang, Jianhua; Debets, A.J.M.; Verweij, P.E.; Melchers, W.J.G.; Zwaan, B.J.; Schoustra, S.E.

    2015-01-01

    Understanding the occurrence and spread of azole resistance in Aspergillus fumigatus is crucial for public health. It has been hypothesized that asexual sporulation, which is abundant in nature, is essential for phenotypic expression of azole resistance mutations in A. fumigatus facilitating

  18. Young female cancer patients' experiences with fertility counselling and fertility preservation

    DEFF Research Database (Denmark)

    Hoeg, Didde; Schmidt, Lone; Tryde Macklon, Kirsten

    2016-01-01

    were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how......Introduction: Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment...... in the public Danish health care system. Methods: Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before...

  19. Postmating sexual conflict and female control over fertilization during gamete interaction.

    Science.gov (United States)

    Firman, Renée C

    2018-06-01

    Males and females rarely have identical evolutionary interests over reproduction, and when the fitness of both sexes is dependent upon paternity outcomes, sexual conflict over fertilization is inevitable. In internal fertilizers, the female tract is a formidable selective force on the number and integrity of sperm that reach the egg. Selection on sperm quality is intensified when females mate multiply and rival males are forced to compete for fertilizations. While male adaptations to sperm competition have been well documented (e.g., increased sperm fertilizing capacity), much less attention has been given to the evolutionary consequences of postmating sexual conflict for egg form and function. Specifically, increased sperm competitiveness can be detrimental by giving rise to an elevation in reproductive failure resulting from polyspermy. Spanning literature on both internal and external fertilizers, in this review I discuss how females respond to sperm competition via fertilization barriers that mediate sperm entry. These findings, which align directly with sexual conflict theory, indicate that females have greater control over fertilization than has previously been appreciated. I then consider the implications of gametic sexual conflict in relation to the development of reproductive isolation and speculate on potential mechanisms accounting for "egg defensiveness." Finally, I discuss the functional significance of egg defensiveness for both the sexes, and sperm selection for females. © 2018 New York Academy of Sciences.

  20. Genome-wide Association Studies for Female Fertility Traits in Chinese and Nordic Holsteins.

    Science.gov (United States)

    Liu, Aoxing; Wang, Yachun; Sahana, Goutam; Zhang, Qin; Liu, Lin; Lund, Mogens Sandø; Su, Guosheng

    2017-08-16

    Reduced female fertility could cause considerable economic loss and has become a worldwide problem in the modern dairy industry. The objective of this study was to detect quantitative trait loci (QTL) for female fertility traits in Chinese and Nordic Holsteins using various strategies. First, single-trait association analyses were performed for female fertility traits in Chinese and Nordic Holsteins. Second, the SNPs with P-value Nordic Holsteins. Third, the summary statistics from single-trait association analyses were combined into meta-analyses to: (1) identify common QTL for multiple fertility traits within each Holstein population; (2) detect SNPs which were associated with a female fertility trait across two Holstein populations. A large numbers of QTL were discovered or confirmed for female fertility traits. The QTL segregating at 31.4~34.1 Mb on BTA13, 48.3~51.9 Mb on BTA23 and 34.0~37.6 Mb on BTA28 shared between Chinese and Nordic Holsteins were further ascertained using a validation approach and meta-analyses. Furthermore, multiple novel variants identified in Chinese Holsteins were validated with Nordic data as well as meta-analyses. The genes IL6R, SLC39A12, CACNB2, ZEB1, ZMIZ1 and FAM213A were concluded to be strong candidate genes for female fertility in Holsteins.

  1. Fertility and sexual function in female Hodgkin lymphoma survivors of reproductive age.

    Science.gov (United States)

    Eeltink, Corien M; Incrocci, Luca; Witte, Birgit I; Meurs, Saskia; Visser, Otto; Huijgens, Peter; Verdonck-de Leeuw, Irma M

    2013-12-01

    To assess the perceived fertility status and to determine the association between perceived fertility status and sexual function, as reported by young female Hodgkin lymphoma survivors. Young female Hodgkin lymphoma survivors are at risk of infertility and impaired sexual function. However, little is known about their awareness of infertility and its association with sexual functioning. A descriptive questionnaire survey. In this cross-sectional study, a survey was completed by female Hodgkin lymphoma survivors (40 years). Outcome measures included self-reported fertility status and sexual problems and the internationally validated Female Sexual Function Index. In total, 36 survivors were included (mean age 32 years, SD 4). Eighteen women (50%) thought themselves fertile. Eight survivors (22%) who perceived themselves as being infertile were more often treated with alkylator-based chemotherapy, and 63% reported sexual dysfunction. Ten survivors (28%) were not aware as to whether they were fertile or not; seven of these would like to have children. The reported fertility status was related to age and chemotherapy regimen. Regarding sexuality, 14 (39%) of the female Hodgkin lymphoma survivors reported one or more sexual problem and none reported recovery. Female sexual dysfunction according to the Female Sexual Function Index was reported by 11 (31%) survivors. Almost 30% of Hodgkin lymphoma survivors do not know whether they are fertile or not. Overall sexual dysfunction is common in Hodgkin lymphoma survivors and comparable to the general population. However, a lack of desire was significantly more often reported in female Hodgkin lymphoma survivors. To prevent assumed infertility and unintended childlessness by postponing parenthood in young female survivors, awareness of fertility status is needed. There is also a need to routinely assess sexual function and provide adequate interventions to improve arousal and lubrication problems. © 2013 John Wiley & Sons Ltd.

  2. Fertility outcome in male and female patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

    Directory of Open Access Journals (Sweden)

    Mahdi Kamoun

    2014-06-01

    Conclusion: Fertility in male and female patients with CAH is reduced. Early and adequate glucocorticoid therapy along with good compliance, careful monitoring of androgen levels and continuous psychological management could contribute to improved fertility rates in this population, even among those with the severe variant.

  3. Female age-related fertility decline. Committee Opinion No. 589.

    Science.gov (United States)

    2014-03-01

    The fecundity of women decreases gradually but significantly beginning approximately at age 32 years and decreases more rapidly after age 37 years. Education and enhanced awareness of the effect of age on fertility are essential in counseling the patient who desires pregnancy. Given the anticipated age-related decline in fertility, the increased incidence of disorders that impair fertility, and the higher risk of pregnancy loss, women older than 35 years should receive an expedited evaluation and undergo treatment after 6 months of failed attempts to conceive or earlier, if clinically indicated. In women older than 40 years, more immediate evaluation and treatment are warranted. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  4. Sperm storage and duration of fertility in female ostriches ( Struthio ...

    African Journals Online (AJOL)

    , the duration of sperm storage and the fertile period following separation of sexes were investigated by egg break-out and by counting the sperm in the perivitelline membrane (spermOPVL) above the germinal disc (GD) region. Fertilisation ...

  5. Overview of industries policies and practices on fertile female and ionizing radiation

    International Nuclear Information System (INIS)

    Burns, L.

    1982-01-01

    Health physicists representing nuclear reactors, government contracting agencies, hospitals and universities, cousulting and personnel firms were surveyed on the policies of their organizations regarding the fertile female and her exposure to ionizing radiation. NCRP Report 39 recommends limiting the exposure of pregnant females to 500 mrem during the gestational period. The responses to the survey questionnaire are summarized

  6. Impact of religious faith & female literacy on fertility in a rural community of west Bengal

    Directory of Open Access Journals (Sweden)

    Mandal N

    2007-01-01

    Full Text Available Background : Role of different social factors on fertility control is evident from different studies. What is the impact of religious faith and female literacy on fertility? Objectives : To study the role of religious faith and female literacy on fertility regulation in a rural community of West Bengal. Methods : Cross Sectional Study at rural field practice area of Department of Community Medicine, NRS Medical College, Kolkata, based on interview of married women in reproductive age group. A total of 671 filled in schedules were analyzed by Epi info package. Results : Average number of pregnancies ever occurred among Muslim mothers (2.8 were higher in comparison with Hindu mothers (1.68. Regarding current fertility, live births in last 2 yrs was more among Muslim mothers (25.2% as compared with their counterparts among Hindu community (12.4%. In both the cases differences were found to be statistically significant. Female literacy was found to have no impact on fertility as a whole, but while stratified, its positive role was evident among Hindu mothers but not among Muslim mothers. Conclusions : Factors, which have made differences in fertility between two religious groups, should be properly assessed and duly addressed for better fertility control in the community.

  7. Female-biased dimorphism underlies a female-specific role for post-embryonic Ilp7 neurons in Drosophila fertility

    Science.gov (United States)

    Castellanos, Monica C.; Tang, Jonathan C. Y.; Allan, Douglas W.

    2013-01-01

    In Drosophila melanogaster, much of our understanding of sexually dimorphic neuronal development and function comes from the study of male behavior, leaving female behavior less well understood. Here, we identify a post-embryonic population of Insulin-like peptide 7 (Ilp7)-expressing neurons in the posterior ventral nerve cord that innervate the reproductive tracts and exhibit a female bias in their function. They form two distinct dorsal and ventral subsets in females, but only a single dorsal subset in males, signifying a rare example of a female-specific neuronal subset. Female post-embryonic Ilp7 neurons are glutamatergic motoneurons innervating the oviduct and are required for female fertility. In males, they are serotonergic/glutamatergic neuromodulatory neurons innervating the seminal vesicle but are not required for male fertility. In both sexes, these neurons express the sex-differentially spliced fruitless-P1 transcript but not doublesex. The male fruitless-P1 isoform (fruM) was necessary and sufficient for serotonin expression in the shared dorsal Ilp7 subset, but although it was necessary for eliminating female-specific Ilp7 neurons in males, it was not sufficient for their elimination in females. By contrast, sex-specific RNA-splicing by female-specific transformer is necessary for female-type Ilp7 neurons in females and is sufficient for their induction in males. Thus, the emergence of female-biased post-embryonic Ilp7 neurons is mediated in a subset-specific manner by a tra- and fru-dependent mechanism in the shared dorsal subset, and a tra-dependent, fru-independent mechanism in the female-specific subset. These studies provide an important counterpoint to studies of the development and function of male-biased neuronal dimorphism in Drosophila. PMID:23981656

  8. Obesity and female fertility: a primary care perspective.

    Science.gov (United States)

    Wilkes, Scott; Murdoch, Alison

    2009-07-01

    Infertility affects approximately one in six couples during their lifetime. Obesity affects approximately half of the general population and is thus a common problem among the fertile population. Obese women have a higher prevalence of infertility compared with their lean counterparts. The majority of women with an ovulatory disorder contributing to their infertility have polycystic ovary syndrome (PCOS) and a significant proportion of women with PCOS are obese. Ovulation disorders and obesity-associated infertility represent a group of infertile couples that are relatively simple to treat. Maternal morbidity, mortality and fetal anomalies are increased with obesity and the success of assisted reproductive technology (ART) treatments is significantly reduced for obese women. Body mass index (BMI) treatment limits for ART throughout the UK vary. The mainstay for treatment is weight loss, which improves both natural fertility and conception rates with ART. The most cost-effective treatment strategy for obese infertile women is weight reduction with a hypo-caloric diet. Assisted reproduction is preferable in women with a BMI of 30 kg/m(2) or less and weight loss strategies should be employed within primary care to achieve that goal prior to referral.

  9. Male chimpanzees' grooming rates vary by female age, parity, and fertility status.

    Science.gov (United States)

    Proctor, Darby P; Lambeth, Susan P; Schapiro, Steven J; Brosnan, Sarah F

    2011-10-01

    Copulation preferences in our closest living relative, the chimpanzee, suggest that males prefer older females who have had previous offspring. However, this finding is counter to some behavioral models, which predict that chimpanzee males, as promiscuous breeders with minimal costs to mating, should show little or no preference when choosing mating partners (e.g. should mate indiscriminately). To determine if the preferences indicated by copulations appear in other contexts as well as how they interact, we examined how male chimpanzees' grooming patterns varied amongst females. We found that males' preferences were based on interactions among females' fertility status, age, and parity. First, grooming increased with increasing female parity. We further found an effect of the estrous cycle on grooming; when females were at the lowest point of their cycle, males preferentially groomed parous females at peak reproductive age, but during maximal tumescence, males preferred the oldest multiparous females. Nulliparous females received relatively little grooming regardless of age or fertility. Thus, male chimpanzees apparently chose grooming partners based on both female's experience and fertility, possibly indicating a two-pronged social investment strategy. Male selectivity seems to have evolved to effectively distribute costly social resources in a pattern which may increase their overall reproductive success. © 2011 Wiley-Liss, Inc.

  10. Characterization and fine mapping of a female fertility associated ...

    Indian Academy of Sciences (India)

    2015-03-12

    Mar 12, 2015 ... 1Key Laboratory of Agriculture Responding to Climate Change, Jiangxi ... Female-sterile line can be used as a pollinator which has a great potential for hybrid seeds production. ... Reciprocal crosses and pollen vitality assay suggest that the .... per plant, and seed-setting rate were investigated in ff1(t).

  11. Fertilization in Flowering Plants: 1. Bringing the Male and Female

    Indian Academy of Sciences (India)

    Crop productivity, floral advertisements, plant diversity, pollination, pollinators, pollination by deceit, stigma, anther, nectar, sexual deception. ... As plants lack mobility, they cannot perform, ontheir own, the most important and primary requirement ofbringing the male (pollen grain) and the female (pistil) partnerstogether.

  12. Fibroblast growth factor 21 has no direct role in regulating fertility in female mice

    Directory of Open Access Journals (Sweden)

    Garima Singhal

    2016-08-01

    Full Text Available Objective: Reproduction is an energetically expensive process. Insufficient calorie reserves, signaled to the brain through peripheral signals such as leptin, suppress fertility. Recently, fibroblast growth factor 21 (FGF21 was implicated as a signal from the liver to the hypothalamus that directly inhibits the hypothalamic–gonadotropin axis during fasting and starvation. However, FGF21 itself increases metabolic rate and can induce weight loss, which suggests that the effects of FGF21 on fertility may not be direct and may reflect changes in energy balance. Methods: To address this important question, we evaluated fertility in several mouse models with elevated FGF21 levels including ketogenic diet fed mice, fasted mice, mice treated with exogenous FGF21 and transgenic mice over-expressing FGF21. Results: We find that ketogenic diet fed mice remain fertile despite significant elevation in serum FGF21 levels. Absence of FGF21 does not alter transient infertility induced by fasting. Centrally infused FGF21 does not suppress fertility despite its efficacy in inducing browning of inguinal white adipose tissue. Furthermore, a high fat diet (HFD can restore fertility of female FGF21-overexpressing mice, a model of growth restriction, even in the presence of supraphysiological serum FGF21 levels. Conclusions: We conclude that FGF21 is not a direct physiological regulator of fertility in mice. The infertility observed in FGF21 overexpressing mice is likely driven by the increased energy expenditure and consequent excess calorie requirements resulting from high FGF21 levels. Keywords: FGF21, Fertility, Leptin, Hypothalamic action

  13. Female labour force status and fertility behaviour in Bangladesh: search for policy interventions.

    Science.gov (United States)

    Chaudhury, R H

    1983-09-01

    This paper examines the effect of female labor force participation on fertility behavior because of its immediate relevance to the formulation of small family norm policies. The hypothesis that female employment is inversely related to fertility and positively related to contraceptive use is based on the following assumptions: 1) the satisfactions of outside employment can substitute for those of child rearing; 2) employment delays marriage and increases the probability of women remaining single, thus reducing fertility; 3) every additional child increases the "opportunity cost" (income lost) of a working mother; 4) a working wife has more status with her husband, and the resultant improved spousal communication leads to more contraceptive use; and 5) working women do not have to rely on their children for support in their old age. Using data from various rural and urban surveys of women in Bangladesh (mostly in Dhaka) and data from the 1961 Bangladesh Population Census, the author finds that fertility is reduced and contraceptive use increases for poor and illiterate women if they work outside the home, but employment has no effect on fertility for higher educated women, who have comparatively fewer children to begin with. In Java, Indonesia, it was found that poor working women have the lowest fertility compared to any other higher socioeconomic group. In Thailand, too, it was found that women who worked outside the home and who had modern values had significantly fewer children than other women. Evaluations of income generating programs for women in Bangladesh attest to the fertility lowering success of integrating family planning and health services with employment programs. Employment through these cooperatives has also indirectly lowered fertility by leading to longer birth spacing and marriage delays. The author recommends such integrated programs and cooperatives because they enhance the social and economic status of women, and by doing so, modernize the

  14. The Effect of a First Child on Female Labor Supply: Evidence from Women Seeking Fertility Services

    Science.gov (United States)

    Cristia, Julian P.

    2008-01-01

    Estimating the causal effect of a first child on female labor supply is complicated by the endogeneity of fertility. This paper addresses this problem by focusing on a sample of women from the National Survey of Family Growth (NSFG) who sought help to become pregnant. After a certain period, only some of these women gave birth. Results using this…

  15. Inter-fertility among female parent clones of pineapple involved in a ...

    African Journals Online (AJOL)

    Inter-fertility among female parent clones of pineapple involved in a 6x6 complete diallel crossing system based on typological approach. AE Issali, AE Badou Nguessan, DF Thiemele, A Amoncho, SB Ngoran Koua, HC Keassemon Kone, ZEB Koffi, A Sangare ...

  16. A sterile sperm caste protects brother fertile sperm from female-mediated death in Drosophila pseudoobscura

    DEFF Research Database (Denmark)

    Holman, Luke; Snook, Rhonda R

    2008-01-01

    antispermicidal mechanisms have been definitively identified. One such adaptation may be the enigmatic infertile sperm morphs or "parasperm" produced by many species, which have been hypothesized to protect their fertile brother "eusperm" from spermicide [2, 3]. Here, we show that female Drosophila pseudoobscura...

  17. Fertility preservation in young females with non-gynaecologic malignancy: an emerging speciality.

    LENUS (Irish Health Repository)

    Smyth, C

    2013-06-06

    BACKGROUND: As new treatment and research advances continue to improve the prognosis of cancer patients, oncologists and surgeons are increasingly faced with the issue of fertility protection and preservation. Cancer patients are frequently exposed to gonadotoxic chemotherapy and radiation therapy as a component of their treatment regimens. There are currently various anticipatory techniques available to women who wish to retain future reproductive ability, the most successful of which involves oocyte retrieval followed by in vitro fertilisation and embryo cryopreservation. Innovative methods include oocyte cryopreservation, ovarian follicle cryopreservation and oophoropexy. AIM: The aim of this study was to examine our combined experiences at Mayo General Hospital of treating female patients (<30 years) with non-gynaecologic malignancy and requiring referral to the HARI Unit during a 6-year period (2007-2012). Emphasis was placed on reviewing the fertility-preservation options available. METHODS: The hospital inpatient enquiry system was inspected for all cases of non-gynaecologic malignancy referred for fertility preservation from 2007 to 2012. RESULTS: Three cases of non-gynaecologic malignancy in young females, with an intention to protect and preserve future fertility were identified. The primary treatment plan did not initially incorporate input from a gynaecology or fertility specialist. It was after concerted inquiry and reflection by both physician and patient that oncofertility consultation was sought. CONCLUSION: The responsibility is on both physicians and surgeons to consider a more holistic approach to cancer care in young female patients, which focuses not only on the elimination of malignancy but also on preservation of fertility and quality of life.

  18. Genome Scan Detects Quantitative Trait Loci Affecting Female Fertility Traits in Danish and Swedish Holstein Cattle

    DEFF Research Database (Denmark)

    Höglund, Johanna Karolina; Guldbrandtsen, B; Su, G

    2009-01-01

    Data from the joint Nordic breeding value prediction for Danish and Swedish Holstein grandsire families were used to locate quantitative trait loci (QTL) for female fertility traits in Danish and Swedish Holstein cattle. Up to 36 Holstein grandsires with over 2,000 sons were genotyped for 416 mic...... for QTL segregating on Bos taurus chromosome (BTA)1, BTA7, BTA10, and BTA26. On each of these chromosomes, several QTL were detected affecting more than one of the fertility traits investigated in this study. Evidence for segregation of additional QTL on BTA2, BTA9, and BTA24 was found...

  19. Attitudes towards motherhood and fertility awareness among 20-40-year-old female healthcare professionals

    DEFF Research Database (Denmark)

    Mortensen, Luise Lermark; Hegaard, Hanne Kristine; Andersen, Anders Nyboe

    2012-01-01

    ABSTRACT Objective To explore attitudes towards family formation and fertility awareness among Danish female healthcare professionals. Methods We collected cross-sectional baseline data from a prospective cohort study of 863 women, ranging in age from 20 to 40 years, working at a hospital...... in Denmark. Information about participants' intentions and attitudes towards family formation and fertility knowledge was gathered by means of a questionnaire. Results Only 2% of the respondents did not want children. Most women believed that motherhood is important, and hoped to have two to three children...

  20. Influence of female sex and fertile age on neuromyelitis optica spectrum disorders.

    Science.gov (United States)

    Borisow, Nadja; Kleiter, Ingo; Gahlen, Anna; Fischer, Katrin; Wernecke, Klaus-Dieter; Pache, Florence; Ruprecht, Klemens; Havla, Joachim; Krumbholz, Markus; Kümpfel, Tania; Aktas, Orhan; Ringelstein, Marius; Geis, Christian; Kleinschnitz, Christoph; Berthele, Achim; Hemmer, Bernhard; Angstwurm, Klemens; Weissert, Robert; Stellmann, Jan-Patrick; Schuster, Simon; Stangel, Martin; Lauda, Florian; Tumani, Hayrettin; Mayer, Christoph; Zeltner, Lena; Ziemann, Ulf; Linker, Ralf A; Schwab, Matthias; Marziniak, Martin; Then Bergh, Florian; Hofstadt-van Oy, Ulrich; Neuhaus, Oliver; Winkelmann, Alexander; Marouf, Wael; Rückriem, Lioba; Faiss, Jürgen; Wildemann, Brigitte; Paul, Friedemann; Jarius, Sven; Trebst, Corinna; Hellwig, Kerstin

    2017-07-01

    Gender and age at onset are important epidemiological factors influencing prevalence, clinical presentation, and treatment response in autoimmune diseases. To evaluate the impact of female sex and fertile age on aquaporin-4-antibody (AQP4-ab) status, attack localization, and response to attack treatment in patients with neuromyelitis optica (NMO) and its spectrum disorders (neuromyelitis optica spectrum disorder (NMOSD)). Female-to-male ratios, diagnosis at last visit (NMO vs NMOSD), attack localization, attack treatment, and outcome were compared according to sex and age at disease or attack onset. A total of 186 NMO/SD patients (82% female) were included. In AQP4-ab-positive patients, female predominance was most pronounced during fertile age (female-to-male ratio 23:1). Female patients were more likely to be positive for AQP4-abs (92% vs 55%; p 40 years. Our data suggest an influence of sex and age on susceptibility to AQP4-ab-positive NMO/SD. Genetic and hormonal factors might contribute to pathophysiology of NMO/SD.

  1. Impact of Radiotherapy on Fertility, Pregnancy, and Neonatal Outcomes in Female Cancer Patients

    International Nuclear Information System (INIS)

    Wo, Jennifer Y.; Viswanathan, Akila N.

    2009-01-01

    Purpose: Radiation has many potential long-term effects on cancer survivors. Female cancer patients may experience decreased fertility depending on the site irradiated. Oncologists should be aware of these consequences and discuss options for fertility preservation before initiating therapy. Methods and Materials: A comprehensive review of the existing literature was conducted. Studies reporting the outcomes for female patients treated with cranio-spinal, abdominal, or pelvic radiation reporting fertility, pregnancy, or neonatal-related outcomes were reviewed. Results: Cranio-spinal irradiation elicited significant hormonal changes in women that affected their ability to become pregnant later in life. Women treated with abdomino-pelvic radiation have an increased rate of uterine dysfunction leading to miscarriage, preterm labor, low birth weight, and placental abnormalities. Early menopause results from low-dose ovarian radiation. Ovarian transposition may decrease the rates of ovarian dysfunction. Conclusions: There is a dose-dependent relationship between ovarian radiation therapy (RT) and premature menopause. Patients treated with RT must be aware of the impact of treatment on fertility and explore appropriate options.

  2. Attitudes towards motherhood and fertility awareness among 20-40-year-old female healthcare professionals.

    Science.gov (United States)

    Mortensen, Luise Lermark; Hegaard, Hanne Kristine; Andersen, Anders Nyboe; Bentzen, Janne Gasseholm

    2012-12-01

    To explore attitudes towards family formation and fertility awareness among Danish female healthcare professionals. We collected cross-sectional baseline data from a prospective cohort study of 863 women, ranging in age from 20 to 40 years, working at a hospital in Denmark. Information about participants' intentions and attitudes towards family formation and fertility knowledge was gathered by means of a questionnaire. Only 2% of the respondents did not want children. Most women believed that motherhood is important, and hoped to have two to three children. About half of the respondents intended to have their last child after the age of 35 years. The most important prerequisites for family formation included: living in a stable relationship, having completed one's studies, a sound financial situation, a job that can be kept when having children, access to public child day care, and the possibility of travelling. As many as 50% of women underrated the impact of a woman's age on fertility, and overestimated the success rates of assisted reproductive technology (ART) treatments. Many female healthcare professionals contemplated giving birth after the age of 35 years. Knowledge of fertility and ART success rates is needed to make well-informed decisions about when to have children.

  3. Marginal distribution and high heterozygosity of asexual Caloglossa vieillardii (Delesseriaceae, Rhodophyta) along the Australian coasts.

    Science.gov (United States)

    Kamiya, Mitsunobu; Saba, Erika; West, John A

    2017-12-01

    In animals and land plants, many asexual species originate through inter- or intraspecific crosses, and such heterozygous asexuals frequently are more abundant than their sexual relatives in marginal habitats. Although asexual species have been reported in various macroalgal taxa, detailed information regarding their distribution, heterozygosity, and origin is limited. Because many asexual tetrasporophyte strains of Caloglossa vieillardii have been isolated from South Australia, far from their core tropical habitats, we re-examined the distribution range of asexual C. vieillardii and genotyped these and other western Pacific strains using an actin gene marker. We confirmed the marginal distribution of the asexuals; however, a small patch of sexual thalli was newly discovered 450 km further west from asexual populations in South Australia. Three heterozygous genotypes and one homozygous genotypes were detected from nine asexual populations; 21 heterozygous strains were obligately asexual, but one homozygous strain suddenly produced sexual gametophytes after several years of culture. We hypothesized that the most abundant heterozygous genotype (defined as type 3/4) in asexual populations occurred by a cross between type 3 and type 4 allele gametophytes, both of which were isolated from the Australian coasts. In the crossing experiments, certain combinations between type 3 females and type 4 males produced tetrasporophytes, which recycled successive tetrasporophytes. In the culture experiments, whereas both sexual and asexual strains successfully produced tetraspores at 12°C, no sexual strains released carpospores below 14°C. However, it is uncertain whether this slight difference of maturation temperature was related to the marginal distribution of asexual C. vieillardii. © 2017 Phycological Society of America.

  4. Female labour force participation in Peru: an analysis using the world fertility survey.

    OpenAIRE

    Rodgers G; Viry D

    1980-01-01

    ILO pub-WEP pub. Working paper analysing woman worker labour force participation trends in Peru based on a world fertility survey - examines female wages employment, unpaid work, occupational structure, labour supply determinants such as population variables (incl. Family structure, marital status, age, internal migration and educational level), husband's characteristics, etc., in rural areas and urban areas, with a view to estimating participation economic models. References.

  5. Young female cancer survivors' use of fertility care after completing cancer treatment

    Science.gov (United States)

    Kim, Jayeon; Mersereau, Jennifer E.; Su, H. Irene; Whitcomb, Brian W.; Malcarne, Vanessa L.; Gorman, Jessica R.

    2016-01-01

    Purpose To investigate factors associated with female young adult cancer survivors’ (YCS) use of fertility care (FC), including consultation or fertility treatment, after completing their cancer treatment. Methods In this cross-sectional study, females between that ages of 18 and 35 years who had been diagnosed with childhood, adolescent, or young adult cancers completed a 20-min web-based survey that included demographics, reproductive history, use of FC, fertility-related informational needs, and reproductive concerns. Results A total of 204 participants completed the survey. Participants’ mean age was 28.3±4.5 years. Thirty (15%) participants reported using FC after cancer treatment. The majority of participants recalled not receiving enough information about FP options at the time of cancer diagnosis (73%). In multivariable analysis, those with higher concerns about having children because of perceived risk to their personal health (P=0.003) were less likely to report use of FC after cancer treatment. Those who had used FC before cancer treatment (P=0.003) and who felt less fertile than age-matched women (P=0.02) were more likely to use FC after their cancer treatment. Conclusions While most YCS in this cohort believed that they did not receive enough information about fertility and most wanted to have children, the vast majority did not seek FC. The findings of this study offer further evidence of the need for improved education and emotional support regarding reproductive options after cancer treatment is completed. Targeted discussions with YCS about appropriate post-treatment FC options may improve providers’ capacity to help YCS meet their parenthood goals. PMID:26939923

  6. Female Labor Supply and Fertility in Iran: A Comparison Between Developed, Semi Developed and Less Developed Regions.

    Science.gov (United States)

    Emamgholipour Sefiddashti, Sara; Homaie Rad, Enayatollah; Arab, Mohamad; Bordbar, Shima

    2016-02-01

    Female labor supply has been changed dramatically in the recent yr. In this study, we examined the effects of development on the relationship between fertility and female labor supply. We used data of population and housing census of Iran and estimated three separate models. To do this we employed Logistic Regressions (BLR). The estimation results of our study showed that there was a negative relationship between fertility rate and female labor supply and there are some differences for this relationship in three models. When fertility rate increases, FLS would decreases. In addition, for higher fertility rates, the woman might be forced to work more because of the economic conditions of her family; and negative coefficients of the fertility rate effects on FLS would increase with a diminishing rate.

  7. Sexual signalling in female crested macaques and the evolution of primate fertility signals.

    Science.gov (United States)

    Higham, James P; Heistermann, Michael; Saggau, Carina; Agil, Muhammad; Perwitasari-Farajallah, Dyah; Engelhardt, Antje

    2012-06-18

    Female signals of fertility have evolved in diverse taxa. Among the most interesting study systems are those of multimale multifemale group-living primates, where females signal fertility to males through multiple signals, and in which there is substantial inter-specific variation in the composition and reliability of such signals. Among the macaques, some species display reliable behavioural and/or anogenital signals while others do not. One cause of this variation may be differences in male competitive regimes: some species show marked sexual dimorphism and reproductive skew, with males fighting for dominance, while others show low dimorphism and skew, with males queuing for dominance. As such, there is variation in the extent to which rank is a reliable proxy for male competitiveness, which may affect the extent to which it is in females' interest to signal ovulation reliably. However, data on ovulatory signals are absent from species at one end of the macaque continuum, where selection has led to high sexual dimorphism and male reproductive skew. Here we present data from 31 cycles of 19 wild female crested macaques, a highly sexually dimorphic species with strong mating skew. We collected measures of ovarian hormone data from faeces, sexual swelling size from digital images, and male and female behaviour. We show that both sexual swelling size and female proceptivity are graded-signals, but relatively reliable indicators of ovulation, with swelling size largest and female proceptive behaviours most frequent around ovulation. Sexual swelling size was also larger in conceptive cycles. Male mating behaviour was well timed to female ovulation, suggesting that males had accurate information about this. Though probabilistic, crested macaque ovulatory signals are relatively reliable. We argue that in species where males fight over dominance, male dominance rank is surrogate for competitiveness. Under these circumstances it is in the interest of females to increase

  8. Epigenetic variation in asexually reproducing organisms

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Preite, V.

    2014-01-01

    The role that epigenetic inheritance can play in adaptation may differ between sexuals and asexuals because (1) the dynamics of adaptation differ under sexual and asexual reproduction and the opportunities offered by epigenetic inheritance may affect these dynamics differently; and (2) in asexual

  9. Male-female crosstalk during pollen germination, tube growth and guidance, and double fertilization.

    Science.gov (United States)

    Dresselhaus, Thomas; Franklin-Tong, Noni

    2013-07-01

    Sperm cells of flowering plants are non-motile and thus require transportation to the egg apparatus via the pollen tube to execute double fertilization. During its journey, the pollen tube interacts with various sporophytic cell types that support its growth and guide it towards the surface of the ovule. The final steps of tube guidance and sperm delivery are controlled by the cells of the female gametophyte. During fertilization, cell-cell communication events take place to achieve and maximize reproductive success. Additional layers of crosstalk exist, including self-recognition and specialized processes to prevent self-fertilization and consequent inbreeding. In this review, we focus on intercellular communication between the pollen grain/pollen tube including the sperm cells with the various sporophytic maternal tissues and the cells of the female gametophyte. Polymorphic-secreted peptides and small proteins, especially those belonging to various subclasses of small cysteine-rich proteins (CRPs), reactive oxygen species (ROS)/NO signaling, and the second messenger Ca(2+), play center stage in most of these processes.

  10. The role of oxidative stress in female infertility and in vitro fertilization

    Directory of Open Access Journals (Sweden)

    Joanna Wojsiat

    2017-05-01

    Full Text Available Infertility problem involves many couples of reproductive age. It has been estimated that in Poland 0.7-1.0 million pairs require treatment, while for more than half of them assisted reproduction is the only recommended and effective method. Infertility affects 13 to 15% of the world’s population. A major concern is the age-related decline in female fertility even more that often a decision about pregnancy is taken at later age. Recent studies show that increased production of reactive oxygen species is an important factor in etiopathogenesis of pregnancy and affects female reproduction. It was found that oxidative stress may damage the oocytes and may impair their fertilization capacity. Oxidative stress may also lead to embryo fragmentation and formation of numerous developmental abnormalities, and is regarded to be one of the important reasons of spontaneous and recurrent miscarriage. Moreover, overproduction of reactive oxygen species has a significant impact on the success of in vitro fertilization (IVF.

  11. Sexual signalling in female crested macaques and the evolution of primate fertility signals

    Directory of Open Access Journals (Sweden)

    Higham James P

    2012-06-01

    Full Text Available Abstract Background Female signals of fertility have evolved in diverse taxa. Among the most interesting study systems are those of multimale multifemale group-living primates, where females signal fertility to males through multiple signals, and in which there is substantial inter-specific variation in the composition and reliability of such signals. Among the macaques, some species display reliable behavioural and/or anogenital signals while others do not. One cause of this variation may be differences in male competitive regimes: some species show marked sexual dimorphism and reproductive skew, with males fighting for dominance, while others show low dimorphism and skew, with males queuing for dominance. As such, there is variation in the extent to which rank is a reliable proxy for male competitiveness, which may affect the extent to which it is in females’ interest to signal ovulation reliably. However, data on ovulatory signals are absent from species at one end of the macaque continuum, where selection has led to high sexual dimorphism and male reproductive skew. Here we present data from 31 cycles of 19 wild female crested macaques, a highly sexually dimorphic species with strong mating skew. We collected measures of ovarian hormone data from faeces, sexual swelling size from digital images, and male and female behaviour. Results We show that both sexual swelling size and female proceptivity are graded-signals, but relatively reliable indicators of ovulation, with swelling size largest and female proceptive behaviours most frequent around ovulation. Sexual swelling size was also larger in conceptive cycles. Male mating behaviour was well timed to female ovulation, suggesting that males had accurate information about this. Conclusion Though probabilistic, crested macaque ovulatory signals are relatively reliable. We argue that in species where males fight over dominance, male dominance rank is surrogate for competitiveness. Under these

  12. Alpha-Fetoprotein: From a Diagnostic Biomarker to a Key Role in Female Fertility

    Directory of Open Access Journals (Sweden)

    Christelle De Mees

    2006-01-01

    Full Text Available Alpha-fetoprotein (AFP is a well-known diagnostic biomarker used in medicine to detect fetal developmental anomalies such as neural tube defects or Down's syndrome, or to follow up the development of tumors such as hepatocellular carcinomas. However, and despite the fact that the protein was discovered almost half a century ago, little was known about its physiological function. The study of Afp knock-out mice uncovered a surprising function of AFP: it is essential for female fertility and for expression of normal female behaviors, and this action is mediated through its estrogen binding capacity. AFP sequestrates estrogens and by so doing protects the female developing brain from deleterious (defeminizing/ masculinizing effects of these hormones

  13. Fertility of Czech Females Could Be Lower than Expected: Trends in Future Development of Age-Specific Fertility Rates up to the Year 2050

    Directory of Open Access Journals (Sweden)

    Ondřej Šimpach

    2015-03-01

    Full Text Available Fertility is an essential aspect of reproduction or population replacement of each country. The challenge for demographers is to model fertility and also to estimate its potential future level for the purposes of population projections. In the case of the Czech Republic we have the population projections provided by the Czech Statistical Office (CZSO with overlooking of the total fertility rate in low, medium and high variant. These estimates despite being based on expert judgments, seem to be too positive compared to the past development of the time series of age-specific fertility rates. The aim of this paper is to assess the situation of fertility in the Czech Republic, to analyse the past development of the time series of age-specific fertility rates using one-dimensional Box-Jenkins models and multidimensional stochastic Lee-Carter approach. Together with found trend in time series and principal components estimated by Lee-Carter’s model a forecasts of age-specific fertility rates up to the year 2050 is constructed. Th ese rates are lower than those provided by CZSO in its three variants of the Czech Republic’s population projection, and therefore we discuss the causes at the end of the paper. We would like to point out that the potential future development of Czech females fertility could be lower than which are currently expected.

  14. Fertility Preservation in Females with Turner Syndrome: A Comprehensive Review and Practical Guidelines

    Science.gov (United States)

    Oktay, K; Bedoschi, G; Berkowitz, K; Bronson, R; Kashani, B; McGovern, P; Pal, L; Quinn, G; Rubin, K

    2016-01-01

    This article reviews the existing fertility preservation options for females diagnosed with Turner syndrome and provides practical guidelines for the practitioner. Turner syndrome is the most common sex chromosome abnormality in females, occurring in approximately one in 2500 live births. Women with Turner syndrome are at extremely high risk for primary ovarian insufficiency (POI) and infertility. Although about 70–80% have no spontaneous pubertal development and 90% experience primary amenorrhea, the remainder may possess a small residual of ovarian follicles at birth or early childhood. The present challenge is to identify these women as early in life as is possible, so as to allow them to benefit from a variety of existing fertility preservation options. To maximize the benefits of fertility preservation, all women with Turner syndrome should be evaluated by an expert as soon as possible in childhood as the vast majority will have their ovarian reserve depleted before adulthood. Cryopreservation of mature oocytes and embryos is a proven fertility preservation approach, while cryopreservation of ovarian tissue is a promising technique with a growing number of live births, but remain investigational. Oocyte cryopreservation has been performed in children with Turner syndrome as young as 13 and ovarian tissue cryopreservation in prepubertal children affected. However, current efficacy of these approaches is unknown in this cohort.. For those who have already lost their ovarian reserve, oocyte or embryo donation and adoption are strategies that allow fulfillment of desire for parenting. For those with Turner syndrome related cardiac contraindications to pregnancy, utilization of gestational surrogacy allows the possibility of biological parenting by using their own oocytes. Alternatively, gestational surrogacy can serve to carry pregnancy resulting from the use of donor oocytes or embryos, if needed. PMID:26485320

  15. Female sexual function and fertility after ileal pouch-anal anastomosis.

    Science.gov (United States)

    Hor, Thevy; Lefevre, Jeremie H; Shields, Conor; Chafai, Najim; Tiret, Emmanuel; Parc, Yann

    2016-03-01

    A potential complication in women after ileal pouch-anal anastomosis (IPAA) is sexual impairment and reduced fertility. The aim was to evaluate sexual function and fertility after IPAA. All female patients who underwent an IPAA between 2004 and 2013 were retrospectively included. Sexual function, fertility, and continence were explored by the female sexual function index (FSFI), telephonic interview, and Wexner's score. Among 127 women included, 93 responded to the questionnaires (73.2%). Seventy five were sexually active, and 48 (64%) had normal sexual function (FSFI > 26). In univariate analysis, there was a significant relationship between ulcerative colitis (p = 0.0161), age > 40 years (p = 0.01311), number of bowel movements (p = 0.0238), nocturnal pouch activity (p = 0.0094), use of loperamide (p = 0.0283), and existence of sexual dysfunction. After multivariate analysis, age and nocturnal pouch activity were associated with a worse sexual function (p = 0.0235, OR = 3.3 (1.2-9.9) and p = 0.0094, OR = 4.1 (1.4-13.5)). Of 16 patients who wished to have children, 10 (63%) became pregnant without recourse to in vitro fertilization, of whom 3 had two or more pregnancies. In total, there were 13 children born after IPAA. The mean time between the first pregnancy and surgery was 24.8 ± 22 months. At 12 and 24 months after cessation of contraception, 57 and 67% had at least one pregnancy. While sexual function is impaired in a limited number of patients, the impact of surgery can be regarded as modest. Age and nocturnal pouch activity were some independent factors of worse sexual function. The risk of infertility should not preclude consideration of IPAA as a treatment option.

  16. Freedom, invisibility, and community: a qualitative study of self-identification with asexuality.

    Science.gov (United States)

    MacNeela, Pádraig; Murphy, Aisling

    2015-04-01

    A significant body of research is now emerging on the subjective meaning of asexuality. This study explored how self-identification as asexual is managed, both as a threat to the self-concept and a source of personal meaning. A total of 66 self-identified asexuals were recruited from an asexuality internet community and responded to open-ended questions on an online survey. Of these, 31 participants identified as female, 15 as male, 18 gave a different label such as genderqueer or androgynous, and two did not provide information on gender. A thematic analysis of the transcripts resulted in three themes. Socially, asexuality attracted denial and resistance due to incompatibility with heteronormative societal expectations. Despite the threat to self-integrity arising from asexuality being socially rejected, it was typically assimilated as a valued and meaningful orientation on an intra-personal level, aided by information and support from the online community. A second level of threat to self arose whereby other self-identifications, especially gender, had to be reconciled with a non-sexual persona. The accommodation made to other elements of the self was reflected in complex sub-identities. The findings were interpreted using identity process theory to understand how threats arising from self-identifying as asexual are managed. Although asexuality emerges as an orientation to sexuality that can be reconciled with the self, its invisibility or outright rejection in society constitute an on-going challenge.

  17. Fertility preservation in females with malignant disease-1: causes, clinical needs and indications

    Directory of Open Access Journals (Sweden)

    Murat Sönmezer

    2009-09-01

    Full Text Available Cancer incidence is progressively increasing in parallel with an increase in the rate of cancer survivors with the help of advanced treatment modalities. By the year 2010, it is estimated that one in every 250 persons will have survived a childhood malignancy. The increased rates of survival bring about complications related to reproductive health. Cytotoxic treatments due to chemo- and radiotherapy or bone marrow transplantation suppress or irreversibly harm not only female ovarian reserve but also male testicular sperm production. In this review, cryopreservation of gametes and gonads with fertility preservation options and indications prior to cancer treatments are discussed.

  18. Female autonomy and fertility: an overview of the situation in South Asia.

    Science.gov (United States)

    1987-12-01

    The persistence of moderate to high fertility in many countries in the South Asian region can be traced to sociocultural factors that prevent women from translating their family size preferences into practice through conscious use of family planning. Female autonomuy -- the ability to obtain information and to use it as the basis for decision making -- is strongly influenced by factors such as kinship and marriage relationships, age, religion, the political system, and the division of labor between the sexes. The complete dependence of younger women on men and older women, deference to age, and lack of access to the outside world combine to make it difficult for South Asian women to practice fertility control. Early marriage increases their exposure to the risk of pregnancy even further. Since women in this region are taught that their own interests are subordinate to those of the family group, they are likely to sacrifice their own desire to regulate fertility. Confronted with social isolation and an insecure future, women turn to children as a potential source of security, especially sons. The forces of modernization have the potential to give South Asian women the autonomy they need to resist pronatalist pressures. Such forces include overall development of the locality, opportunities for education and employment, legal reforms, the presence of change agents, the availability of family planning clinics, and the adoption of innovations in the immediate environment.

  19. Long-term effects of prenatal X ray on development and fertility of human females

    International Nuclear Information System (INIS)

    Meyer, M.B.; Tonascia, J.A.; Merz, T.

    1976-01-01

    This continuing epidemiologic study investigates possible effects of X-ray exposure during foetal life on the subsequent development and fertility of human females and on their offspring. The study population comprises 1458 females exposed in utero to maternal diagnostic X ray such as pelvimetry, and 1458 unexposed controls matched by hospital of birth, parity, race and birthdate (1947-1952). Phase I of the study showed a 10-15% increase in fertility in young exposed women, based on ascertainment of live births and foetal deaths registered in Baltimore City. This statistically significant difference (p=0.011) remained after adjustment for differences between exposed and control women in economic, social and medical factors. Phase II of the study, a direct follow-up of exposed control pairs of women now aged 22-28, continues to show more total pregnancies among exposed women. Exposed-in-utero women had 15% more total pregnancies than controls in 1960-1969, and 7% more in 1970-1975. Exposed and control women are similar in number of siblings, number of children wanted, contraceptive use, and frequency of therapeutic abortion. Other findings suggest possible exposed-control differences in growth, development and behaviour. Exposed women have completed fewer grades of school, have poorer general health, more menstrual problems, more of certain diseases and accidents, and are heavier for height than controls. (author)

  20. Sexual and asexual oogenesis require the expression of unique and shared sets of genes in the insect Acyrthosiphon pisum

    Directory of Open Access Journals (Sweden)

    Gallot Aurore

    2012-02-01

    Full Text Available Abstract Background Although sexual reproduction is dominant within eukaryotes, asexual reproduction is widespread and has evolved independently as a derived trait in almost all major taxa. How asexuality evolved in sexual organisms is unclear. Aphids, such as Acyrthosiphon pisum, alternate between asexual and sexual reproductive means, as the production of parthenogenetic viviparous females or sexual oviparous females and males varies in response to seasonal photoperiodism. Consequently, sexual and asexual development in aphids can be analyzed simultaneously in genetically identical individuals. Results We compared the transcriptomes of aphid embryos in the stages of development during which the trajectory of oogenesis is determined for producing sexual or asexual gametes. This study design aimed at identifying genes involved in the onset of the divergent mechanisms that result in the sexual or asexual phenotype. We detected 33 genes that were differentially transcribed in sexual and asexual embryos. Functional annotation by gene ontology (GO showed a biological signature of oogenesis, cell cycle regulation, epigenetic regulation and RNA maturation. In situ hybridizations demonstrated that 16 of the differentially-transcribed genes were specifically expressed in germ cells and/or oocytes of asexual and/or sexual ovaries, and therefore may contribute to aphid oogenesis. We categorized these 16 genes by their transcription patterns in the two types of ovaries; they were: i expressed during sexual and asexual oogenesis; ii expressed during sexual and asexual oogenesis but with different localizations; or iii expressed only during sexual or asexual oogenesis. Conclusions Our results show that asexual and sexual oogenesis in aphids share common genetic programs but diverge by adapting specificities in their respective gene expression profiles in germ cells and oocytes.

  1. Substance p regulates puberty onset and fertility in the female mouse.

    Science.gov (United States)

    Simavli, Serap; Thompson, Iain R; Maguire, Caroline A; Gill, John C; Carroll, Rona S; Wolfe, Andrew; Kaiser, Ursula B; Navarro, Víctor M

    2015-06-01

    Puberty is a tightly regulated process that leads to reproductive capacity. Kiss1 neurons are crucial in this process by stimulating GnRH, yet how Kiss1 neurons are regulated remains unknown. Substance P (SP), an important neuropeptide in pain perception, induces gonadotropin release in adult mice in a kisspeptin-dependent manner. Here, we assessed whether SP, through binding to its receptor NK1R (neurokinin 1 receptor), participates in the timing of puberty onset and fertility in the mouse. We observed that 1) selective NK1R agonists induce gonadotropin release in prepubertal females; 2) the expression of Tac1 (encoding SP) and Tacr1 (NK1R) in the arcuate nucleus is maximal before puberty, suggesting increased SP tone; 3) repeated exposure to NK1R agonists prepubertally advances puberty onset; and 4) female Tac1(-/-) mice display delayed puberty; moreover, 5) SP deficiency leads to subfertility in females, showing fewer corpora lutea and antral follicles and leading to decreased litter size. Thus, our findings support a role for SP in the stimulation of gonadotropins before puberty, acting via Kiss1 neurons to stimulate GnRH release, and its involvement in the attainment of full reproductive capabilities in female mice.

  2. Cdc20 is critical for meiosis I and fertility of female mice.

    Directory of Open Access Journals (Sweden)

    Fang Jin

    2010-09-01

    Full Text Available Chromosome missegregation in germ cells is an important cause of unexplained infertility, miscarriages, and congenital birth defects in humans. However, the molecular defects that lead to production of aneuploid gametes are largely unknown. Cdc20, the activating subunit of the anaphase-promoting complex/cyclosome (APC/C, initiates sister-chromatid separation by ordering the destruction of two key anaphase inhibitors, cyclin B1 and securin, at the transition from metaphase to anaphase. The physiological significance and full repertoire of functions of mammalian Cdc20 are unclear at present, mainly because of the essential nature of this protein in cell cycle progression. To bypass this problem we generated hypomorphic mice that express low amounts of Cdc20. These mice are healthy and have a normal lifespan, but females produce either no or very few offspring, despite normal folliculogenesis and fertilization rates. When mated with wild-type males, hypomorphic females yield nearly normal numbers of fertilized eggs, but as these embryos develop, they become malformed and rarely reach the blastocyst stage. In exploring the underlying mechanism, we uncover that the vast majority of these embryos have abnormal chromosome numbers, primarily due to chromosome lagging and chromosome misalignment during meiosis I in the oocyte. Furthermore, cyclin B1, cyclin A2, and securin are inefficiently degraded in metaphase I; and anaphase I onset is markedly delayed. These results demonstrate that the physiologically effective threshold level of Cdc20 is high for female meiosis I and identify Cdc20 hypomorphism as a mechanism for chromosome missegregation and formation of aneuploid gametes.

  3. Low-Dose Aspirin Treatment Alleviates Gamma Irradiation Impaired Fertility in Female Albino Rats

    International Nuclear Information System (INIS)

    Ibrahim, M.F.

    2013-01-01

    Recent experimental evidence suggests that Aspirin (acetylsalicylic acid), the extensively prescribed analgesic, can improve female fertility by suppressing the prostaglandin (PG) biosynthesis and modulating the uterine circulation. Aspirin has also been found to exhibit a protective ability on the radiation induced oxidative stress. Thus the present work aims to investigate the effect of oral low-dose Aspirin treatment on the radiation induced female reproductive disturbance. Adult female rats were used in the current experiment. All rat group treatments started at the onset of the proestrus phase and terminated at the diestrus encompassing 2 complete estrus cycles. Subsequently, the rats were divided into 4 equal groups: Group 1-Control: female rats receiving distilled water via an oral gavage; Group 2- Irradiation: female rats subjected to 6 Gy gamma rays at the proestrus cycle and receiving distilled water; Group 3-Aspirin: rats orally administered a daily dose of 7mg/kg body weight aspirin dissolved in distilled water via an oral gavage and Group 4- Irradiation + Aspirin: female rats irradiated as group 2 and receiving aspirin treatment. A number of rats from each experimental group were allowed to mate following every treatment to serve as Control mated (Subgroup 1), Irradiated mated (Subgroup 2), Aspirin administered mated (Subgroup 3) and Irradiated + Aspirin treated mated (Subgroup 4). At the assigned day of the second estrus cycle completion, blood was collected from Groups 1-4 for subsequent hormonal assay, lipid peroxides and glutathione (GSH) estimation whereas Subgroups 1-4 were carefully monitored for reproduction and infertility rates. Results have shown that the 6 Gy γ- irradiation of the rats at the proestrus cycle (Group 2) caused a decrease in follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL) and estradiol (E2) levels associated with a drastic increase in the progesterone levels in addition to the significant

  4. Possible Outcome of Fenugreek Seeds Powder Administration on the Fertility of Female and Male Albino Rat

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, M F; El-Tawill, G.A., E-mail: gkyrillos@hotmail.co [Radiation Biology Department, National Centre for Radiation Research and Technology (NCRRT), Atomic Energy Authority, Cairo (Egypt)

    2010-07-01

    Fenugreek (Trigonella foenum-graecum) is an annual plant from the family of Papilionaceae-Leguminosae that has been credited with many medicinal properties. The current study aims to evaluate the possible fertility activity of fenugreek seeds powder on female and male albino rats. To achieve the theme, fenugreek seeds powder (200 mg/rat) were daily administered orally to both female and male Wistar rats for 15 and 30 consecutive days, after which the rats were sacrificed for both biochemical and histopathological observations. Fenugreek treatment significantly decreased the serum cholesterol levels in both female and male rats with a marked increase in the ovary and testis cholesterol levels following 30 days of consecutive administration. The circulating serum female hormones showed an initial elevation at the end of 15 days of fenugreek intake followed by a significant drop in the group of rats that continued to receive the daily fenugreek dose for 30 days. These observations were supported by the notable decline in the ovarian weights further validated by their ovarian histological sections revealing remarkable dissolution of some follicles and prominent abundance of inflammatory cells. In the 30 days interval treated males, the serum testosterone hormone concentrations significantly declined and the testis weights were reduced with evident damage to the seminiferous tubules and interstitial tissues as shown by the histopathological picture of testis tissue sections. Accordingly, it can be deduced that fenugreek seeds powder exert a significant antifertility adverse effect on the female and male rats when supplemented at a considerable dose for an extended time interval

  5. Modelling female fertility traits in beef cattle using linear and non-linear models.

    Science.gov (United States)

    Naya, H; Peñagaricano, F; Urioste, J I

    2017-06-01

    Female fertility traits are key components of the profitability of beef cattle production. However, these traits are difficult and expensive to measure, particularly under extensive pastoral conditions, and consequently, fertility records are in general scarce and somehow incomplete. Moreover, fertility traits are usually dominated by the effects of herd-year environment, and it is generally assumed that relatively small margins are kept for genetic improvement. New ways of modelling genetic variation in these traits are needed. Inspired in the methodological developments made by Prof. Daniel Gianola and co-workers, we assayed linear (Gaussian), Poisson, probit (threshold), censored Poisson and censored Gaussian models to three different kinds of endpoints, namely calving success (CS), number of days from first calving (CD) and number of failed oestrus (FE). For models involving FE and CS, non-linear models overperformed their linear counterparts. For models derived from CD, linear versions displayed better adjustment than the non-linear counterparts. Non-linear models showed consistently higher estimates of heritability and repeatability in all cases (h 2  linear models; h 2  > 0.23 and r > 0.24, for non-linear models). While additive and permanent environment effects showed highly favourable correlations between all models (>0.789), consistency in selecting the 10% best sires showed important differences, mainly amongst the considered endpoints (FE, CS and CD). In consequence, endpoints should be considered as modelling different underlying genetic effects, with linear models more appropriate to describe CD and non-linear models better for FE and CS. © 2017 Blackwell Verlag GmbH.

  6. Does fertility status influence impulsivity and risk taking in human females? Adaptive influences on intertemporal choice and risky decision making.

    Science.gov (United States)

    Kaighobadi, Farnaz; Stevens, Jeffrey R

    2013-07-18

    Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males), become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted--i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

  7. Does Fertility Status Influence Impulsivity and Risk Taking in Human Females? Adaptive Influences on Intertemporal Choice and Risky Decision Making

    Directory of Open Access Journals (Sweden)

    Farnaz Kaighobadi

    2013-07-01

    Full Text Available Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males, become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted—i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

  8. Sexual conflict and the evolution of asexuality at low population densities.

    Science.gov (United States)

    Gerber, Nina; Kokko, Hanna

    2016-10-26

    Theories for the evolution of sex rarely include facultatively sexual reproduction. Sexual harassment by males is an underappreciated factor: it should at first sight increase the relative advantage of asexual reproduction by increasing the cost of sex. However, if the same females can perform either sexual or asexual life cycles, then females trying to reproduce asexually may not escape harassment. If resisting male harassment is costly, it might be beneficial for a female to accept a mating and undertake a sexual life cycle rather than 'insist' on an asexual one. We investigate the effects of sexual harassment on the maintenance of sex under different population densities. Our model shows that resisting matings pays off at low population densities, which leads to the complete extinction of males, and thus to the evolution of completely asexual populations. Facultative sex persists in a narrow range of slightly higher densities. At high densities, selection favours giving up resisting male mating attempts and thus sexual reproduction takes over. These interactions between the outcomes of sexual conflict and population density suggest an explanation for the rarity of facultative sex and also patterns of geographical parthenogenesis, where marginal environments with potentially low densities are associated with asexuality. © 2016 The Author(s).

  9. Rac1 is dispensable for oocyte maturation and female fertility in vivo.

    Science.gov (United States)

    Hao, Jian-Xiu; Meng, Tie-Gang; Fan, Li-Hua; Yao, Yuan-Qing

    2017-01-01

    Oocyte maturation, the important process to produce female haploid gamete, accompanies with polarity establishment and highly asymmetric cell division to emit minor polar body within little cytoplasm. Microfilaments play central roles in polarity establishment and asymmetric cell division. Several actin regulators like WASP protein family as well as small GTPases function in microfilament dynamics, involving the process. Rac1, one member of RhoGTPases, has been reported to regulate the polarity and asymmetric cell division in mouse oocytes in vitro. The physiological role of Rac1 in mouse oocyte remains unknown. By conditional knockout technology, we specifically deleted Rac1 gene in mouse oocyte, and found that Rac1 deletion exerted little effect on mouse oocyte maturation including polarity establishment and asymmetric division, and the mutant mice showed normal fertility.

  10. Intrauterine Exposure to Paracetamol and Aniline Impairs Female Reproductive Development by Reducing Follicle Reserves and Fertility

    DEFF Research Database (Denmark)

    Holm, Jacob Bak; Mazaud-Guittot, Severine; Danneskiold-Samsøe, Niels Banhos

    2016-01-01

    in shortening of the anogenital distance in adult offspring, suggesting that fetal hormone signaling had been disturbed. Female offspring of paracetamol-exposed mothers had ovaries with diminished follicle reserve and reduced fertility. Fetal gonads of exposed animals had also reduced gonocyte numbers......, suggesting that the reduced follicle count in adults could be due to early disruption of germ cell development. However, ex vivo cultures of ovaries from 12.5 days post coitum fetuses showed no decrease in proliferation or expression following exposure to paracetamol. This suggests that the effect...... of paracetamol occurs prior to this developmental stage. Accordingly, using embryonic stem cells as a proxy for primordial germ cells we show that paracetamol is an inhibitor of cellular proliferation, but without cytotoxic effects. Collectively, our data show that intrauterine exposure to paracetamol at levels...

  11. How the FMR1 gene became relevant to female fertility and reproductive medicine

    Directory of Open Access Journals (Sweden)

    Norbert eGleicher

    2014-08-01

    Full Text Available This manuscript describes the 6-year evolution of our center’s research into ovarian functions of the FMR1 gene, which led to the identification of a new normal CGGn range of 26-34. This new normal range, in turn, led to definitions of different alleles (haplotypes based on whether no, one or both alleles are within range. Specific alleles then were demonstrated to represent distinct ovarian aging patterns, suggesting an important FMR1 function in follicle recruitment and ovarian depletion of follicles. So called low alleles, characterized by CGGn34 alleles. Because low FMR1 alleles present in approximately 25% of all females, FMR1 testing at young ages may offer an opportunity for earlier diagnosis of OPOI than current practice allows. Earlier diagnosis of OPOI, in turn, would give young women the options of reassessing their reproductive schedules and/or pursue fertility preservation via oocyte cryopreservation when most effective.

  12. How Large Asexual Populations Adapt

    Science.gov (United States)

    Desai, Michael

    2007-03-01

    We often think of beneficial mutations as being rare, and of adaptation as a sequence of selected substitutions: a beneficial mutation occurs, spreads through a population in a selective sweep, then later another beneficial mutation occurs, and so on. This simple picture is the basis for much of our intuition about adaptive evolution, and underlies a number of practical techniques for analyzing sequence data. Yet many large and mostly asexual populations -- including a wide variety of unicellular organisms and viruses -- live in a very different world. In these populations, beneficial mutations are common, and frequently interfere or cooperate with one another as they all attempt to sweep simultaneously. This radically changes the way these populations adapt: rather than an orderly sequence of selective sweeps, evolution is a constant swarm of competing and interfering mutations. I will describe some aspects of these dynamics, including why large asexual populations cannot evolve very quickly and the character of the diversity they maintain. I will explain how this changes our expectations of sequence data, how sex can help a population adapt, and the potential role of ``mutator'' phenotypes with abnormally high mutation rates. Finally, I will discuss comparisons of these predictions with evolution experiments in laboratory yeast populations.

  13. Coming to an Asexual Identity: Negotiating Identity, Negotiating Desire.

    Science.gov (United States)

    Scherrer, Kristin S

    2008-10-01

    Sexuality is generally considered an important aspect of self-hood. Therefore, individuals who do not experience sexual attraction, and embrace an asexual identity are in a unique position to inform the social construction of sexuality. This study explores the experiences of asexual individuals utilizing open ended Internet survey data from 102 self-identified asexual people. In this paper I describe several distinct aspects of asexual identities: the meanings of sexual, and therefore, asexual behaviors, essentialist characterizations of asexuality, and lastly, interest in romance as a distinct dimension of sexuality. These findings have implications not only for asexual identities, but also for the connections of asexuality with other marginalized sexualities.

  14. LH prevents cisplatin-induced apoptosis in oocytes and preserves female fertility in mouse.

    Science.gov (United States)

    Rossi, Valerio; Lispi, Monica; Longobardi, Salvatore; Mattei, Maurizio; Rella, Francesca Di; Salustri, Antonietta; De Felici, Massimo; Klinger, Francesca G

    2017-01-01

    Premature ovarian failure and female infertility are frequent side effects of anticancer therapies, owing to the extreme sensitivity of the ovarian reserve oocytes to the damaging effects of irradiation and chemotherapy on DNA. We report here a robust protective effect of luteinizing hormone (LH) on the primordial follicle pool of prepubertal ovaries against the cisplatin (Cs)-induced apoptosis. In vitro LH treatment of prepubertal ovarian fragments generated anti-apoptotic signals by a subset of ovarian somatic cells expressing LH receptor (LHR) through cAMP/PKA and Akt pathways. Such signals, reducing the oocyte level of pro-apoptotic TAp63 protein and favoring the repair of the Cs-damaged DNA in the oocytes, prevented their apoptosis. Noteworthy, in vivo administration to prepubertal female mice of a single dose of LH together with Cs inhibited the depletion of the primordial follicle reserve caused by the drug and preserved their fertility in reproductive age, preventing significant alteration in the number of pregnancy and of delivered pups. In conclusion, these findings establish a novel ovoprotective role for LH and further support the very attracting prospective to use physiological 'fertoprotective' approaches for preventing premature infertility and risks linked to precocious menopause in young patients who survived cancer after chemotherapy.

  15. LH prevents cisplatin-induced apoptosis in oocytes and preserves female fertility in mouse

    Science.gov (United States)

    Rossi, Valerio; Lispi, Monica; Longobardi, Salvatore; Mattei, Maurizio; Rella, Francesca Di; Salustri, Antonietta; De Felici, Massimo; Klinger, Francesca G

    2017-01-01

    Premature ovarian failure and female infertility are frequent side effects of anticancer therapies, owing to the extreme sensitivity of the ovarian reserve oocytes to the damaging effects of irradiation and chemotherapy on DNA. We report here a robust protective effect of luteinizing hormone (LH) on the primordial follicle pool of prepubertal ovaries against the cisplatin (Cs)-induced apoptosis. In vitro LH treatment of prepubertal ovarian fragments generated anti-apoptotic signals by a subset of ovarian somatic cells expressing LH receptor (LHR) through cAMP/PKA and Akt pathways. Such signals, reducing the oocyte level of pro-apoptotic TAp63 protein and favoring the repair of the Cs-damaged DNA in the oocytes, prevented their apoptosis. Noteworthy, in vivo administration to prepubertal female mice of a single dose of LH together with Cs inhibited the depletion of the primordial follicle reserve caused by the drug and preserved their fertility in reproductive age, preventing significant alteration in the number of pregnancy and of delivered pups. In conclusion, these findings establish a novel ovoprotective role for LH and further support the very attracting prospective to use physiological 'fertoprotective' approaches for preventing premature infertility and risks linked to precocious menopause in young patients who survived cancer after chemotherapy. PMID:27689876

  16. Severe Fertility Effects of sheepish Sperm Caused by Failure To Enter Female Sperm Storage Organs in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Masatoshi Tomaru

    2018-01-01

    Full Text Available In Drosophila, mature sperm are transferred from males to females during copulation, stored in the sperm storage organs of females, and then utilized for fertilization. Here, we report a gene named sheepish (shps of Drosophila melanogaster that is essential for sperm storage in females. shps mutant males, although producing morphologically normal and motile sperm that are effectively transferred to females, produce very few offspring. Direct counts of sperm indicated that the primary defect was correlated to failure of shps sperm to migrate into the female sperm storage organs. Increased sperm motion parameters were seen in the control after transfer to females, whereas sperm from shps males have characteristics of the motion parameters different from the control. The few sperm that occasionally entered the female sperm storage organs showed no obvious defects in fertilization and early embryo development. The female postmating responses after copulation with shps males appeared normal, at least with respect to conformational changes of uterus, mating plug formation, and female remating rates. The shps gene encodes a protein with homology to amine oxidases, including as observed in mammals, with a transmembrane region at the C-terminal end. The shps mutation was characterized by a nonsense replacement in the third exon of CG13611, and shps was rescued by transformants of the wild-type copy of CG13611. Thus, shps may define a new class of gene responsible for sperm storage.

  17. Through the smoke: Use of in vivo and in vitro cigarette smoking models to elucidate its effect on female fertility

    International Nuclear Information System (INIS)

    Camlin, Nicole J.; McLaughlin, Eileen A.; Holt, Janet E.

    2014-01-01

    A finite number of oocytes are established within the mammalian ovary prior to birth to form a precious ovarian reserve. Damage to this limited pool of gametes by environmental factors such as cigarette smoke and its constituents therefore represents a significant risk to a woman's reproductive capacity. Although evidence from human studies to date implicates a detrimental effect of cigarette smoking on female fertility, these retrospective studies are limited and present conflicting results. In an effort to more clearly understand the effect of cigarette smoke, and its chemical constituents, on female fertility, a variety of in vivo and in vitro animal models have been developed. This article represents a systematic review of the literature regarding four of experimental model types: 1) direct exposure of ovarian cells and follicles to smoking constituents’ in vitro, 2) direct exposure of whole ovarian tissue with smoking constituents in vitro, 3) whole body exposure of animals to smoking constituents and 4) whole body exposure of animals to cigarette smoke. We summarise key findings and highlight the strengths and weaknesses of each model system, and link these to the molecular mechanisms identified in smoke-induced fertility changes. - Highlights: • In vivo exposure to individual cigarette smoke chemicals alters female fertility. • The use of in vitro models in determining molecular mechanisms • Whole cigarette smoke inhalation animal models negatively affect ovarian function

  18. Through the smoke: Use of in vivo and in vitro cigarette smoking models to elucidate its effect on female fertility

    Energy Technology Data Exchange (ETDEWEB)

    Camlin, Nicole J. [School of Environment and Life Sciences, University of Newcastle, Callaghan, NSW 2308 (Australia); McLaughlin, Eileen A., E-mail: eileen.mclaughlin@newcastle.edu.au [School of Environment and Life Sciences, University of Newcastle, Callaghan, NSW 2308 (Australia); Holt, Janet E. [School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308 (Australia)

    2014-12-15

    A finite number of oocytes are established within the mammalian ovary prior to birth to form a precious ovarian reserve. Damage to this limited pool of gametes by environmental factors such as cigarette smoke and its constituents therefore represents a significant risk to a woman's reproductive capacity. Although evidence from human studies to date implicates a detrimental effect of cigarette smoking on female fertility, these retrospective studies are limited and present conflicting results. In an effort to more clearly understand the effect of cigarette smoke, and its chemical constituents, on female fertility, a variety of in vivo and in vitro animal models have been developed. This article represents a systematic review of the literature regarding four of experimental model types: 1) direct exposure of ovarian cells and follicles to smoking constituents’ in vitro, 2) direct exposure of whole ovarian tissue with smoking constituents in vitro, 3) whole body exposure of animals to smoking constituents and 4) whole body exposure of animals to cigarette smoke. We summarise key findings and highlight the strengths and weaknesses of each model system, and link these to the molecular mechanisms identified in smoke-induced fertility changes. - Highlights: • In vivo exposure to individual cigarette smoke chemicals alters female fertility. • The use of in vitro models in determining molecular mechanisms • Whole cigarette smoke inhalation animal models negatively affect ovarian function.

  19. MicroRNAs: From Female Fertility, Germ Cells, and Stem Cells to Cancer in Humans

    Directory of Open Access Journals (Sweden)

    Irma Virant-Klun

    2016-01-01

    Full Text Available MicroRNAs are a family of naturally occurring small noncoding RNA molecules that play an important regulatory role in gene expression. They are suggested to regulate a large proportion of protein encoding genes by mediating the translational suppression and posttranscriptional control of gene expression. Recent findings show that microRNAs are emerging as important regulators of cellular differentiation and dedifferentiation, and are deeply involved in developmental processes including human preimplantation development. They keep a balance between pluripotency and differentiation in the embryo and embryonic stem cells. Moreover, it became evident that dysregulation of microRNA expression may play a fundamental role in progression and dissemination of different cancers including ovarian cancer. The interest is still increased by the discovery of exosomes, that is, cell-derived vesicles, which can carry different proteins but also microRNAs between different cells and are involved in cell-to-cell communication. MicroRNAs, together with exosomes, have a great potential to be used for prognosis, therapy, and biomarkers of different diseases including infertility. The aim of this review paper is to summarize the existent knowledge on microRNAs related to female fertility and cancer: from primordial germ cells and ovarian function, germinal stem cells, oocytes, and embryos to embryonic stem cells.

  20. Emergency IVF for embryo freezing to preserve female fertility: a French multicentre cohort study.

    Science.gov (United States)

    Courbiere, B; Decanter, C; Bringer-Deutsch, S; Rives, N; Mirallié, S; Pech, J C; De Ziegler, D; Carré-Pigeon, F; May-Panloup, P; Sifer, C; Amice, V; Schweitzer, T; Porcu-Buisson, G; Poirot, C

    2013-09-01

    What are the outcomes of French emergency IVF procedures involving embryo freezing for fertility preservation before gonadotoxic treatment? Pregnancy rates after emergency IVF, cryopreservation of embryos, storage, thawing and embryo transfer (embryo transfer), in the specific context of the preservation of female fertility, seem to be similar to those reported for infertile couples undergoing ART. A French retrospective multicentre cohort study initiated by the GRECOT network-the French Study Group for Ovarian and Testicular Cryopreservation. We sent an e-mail survey to the 97 French centres performing the assisted reproduction technique in 2011, asking whether the centre performed emergency IVF and requesting information about the patients' characteristics, indications, IVF cycles and laboratory and follow-up data. The response rate was 53.6% (52/97). Fourteen French centres reported that they performed emergency IVF (56 cycles in total) before gonadotoxic treatment, between 1999 and July 2011, in 52 patients. The patients had a mean age of 28.9 ± 4.3 years, and a median length of relationship of 3 years (1 month-15 years). Emergency IVF was indicated for haematological cancer (42%), brain tumour (23%), sarcoma (3.8%), mesothelioma (n = 1) and bowel cancer (n = 1). Gynaecological problems accounted for 17% of indications. In 7.7% of cases, emergency IVF was performed for autoimmune diseases. Among the 52 patients concerned, 28% (n = 14) had undergone previous courses of chemotherapy before beginning controlled ovarian stimulation (COS). The initiation of gonadotoxic treatment had to be delayed in 34% of the patients (n = 19). In total, 56 cycles were initiated. The mean duration of stimulation was 11.2 ± 2.5 days, with a mean peak estradiol concentration on the day on which ovulation was triggered of 1640 ± 1028 pg/ml. Three cycles were cancelled due to ovarian hyperstimulation syndrome (n = 1), poor response (n = 1) and treatment error (n = 1). A mean of 8

  1. On the age-specific correlation between fertility and female employment: Heterogeneity over space and time in OECD countries

    Directory of Open Access Journals (Sweden)

    Uta Brehm

    2015-03-01

    Full Text Available Background: Though there has been profound research on the curious change in correlation between total fertility rate (TFR and female labor force participation (FLP in the mid-1980s, aspects of the compositional character of age-specific effects and the nature of countries' heterogeneity have been neglected. Objective: The present paper aims to contribute to filling this gap by analyzing annual total fertility rates and their equivalents for four age groups between 20 and 39 years as well as the respective lagged FLP from 17 OECD countries between 1985 and 2010. Methods: Random Intercept and Random Coefficient Models are applied, allowing us to assess both effects and country heterogeneity in slopes and intercepts. Results: The analyses reveal that the development of the correlation between FLP and TFR after 1985 is comprised of very different relations between age-specific fertility and labor participation. The youngest group's situation is determined by a decrease in both fertility and FLP, while countries' effects differ increasingly. The oldest women's fertility decisions seem to be detached from labor market influences, though country variation is high. Women in their late 20s and early 30s, in contrast, appear to be most affected by the incompatibility of childbearing and gainful employment. Though these effects seem to have overcome their low points during the mid-1990s, only women in their early 30s show country-convergence. Conclusions: The results highlight the fact that total and age-specific fertility behavior, FLP-effects and country variances are distinct concepts that add considerably to the broad understanding of the correlation between fertility and FLP.

  2. Male and female experiences of having fertility matters raised alongside a cancer diagnosis during the teenage and young adult years.

    Science.gov (United States)

    Crawshaw, M A; Glaser, A W; Hale, J P; Sloper, P

    2009-07-01

    Discussion and management of potential reproductive health sequelae of adolescent cancer are essential and challenging components of care for the multidisciplinary team. Despite this, research has been limited to specific experiences (e.g. sperm banking) or fertility-related concerns of adult survivors. This grounded theory study of 38 male and female survivors of adolescent cancer aged 16-30 years drew on in-depth single interviews to map the range of experiences of being advised that treatment might affect fertility. Strong support for being told at around diagnosis was found regardless of gender, age, incapacity or availability of fertility preservation services. Age and life stage appeared less significant for impact than the perceived level of threat to personal and social well-being. Women were more likely to achieve lower levels of comprehension about the physiological impact, to report later distress from lack of fertility preservation services and to revisit more frequently those decisions made by the few offered fertility preservation. Men found decision making about sperm banking straightforward on the whole and reported satisfaction with having the choice regardless of outcome. Findings suggest that young people can cope with this information alongside diagnosis especially when professional and parental support is proportionate to the particular impact on them.

  3. Gendered Divisions of Fertility Work: Socioeconomic Predictors of Female versus Male Sterilization

    Science.gov (United States)

    Bertotti, Andrea M.

    2013-01-01

    Domestic labor researchers have examined a multitude of duties disproportionately performed by women, yet the responsibility associated with navigating a couple's fertility--fertility work--has been overlooked. Using data from the 2006-2010 National Survey of Family Growth ("N" = 1,415), the author examined how racial and socioeconomic…

  4. Genome-wide association mapping for female fertility traits in Danish and Swedish Holstein cattle

    DEFF Research Database (Denmark)

    Sahana, G; Guldbrandtsen, B; Bendixen, C

    2010-01-01

    A genome-wide association study was conducted using a mixed model analysis for QTL for fertility traits in Danish and Swedish Holstein cattle. The analysis incorporated 2,531 progeny tested bulls, and a total of 36 387 SNP markers on 29 bovine autosomes were used. Eleven fertility traits were ana...

  5. Fertility information needs and concerns post-treatment contribute to lowered quality of life among young adult female cancer survivors.

    Science.gov (United States)

    Benedict, Catherine; Thom, Bridgette; Friedman, Danielle N; Pottenger, Elaine; Raghunathan, Nirupa; Kelvin, Joanne F

    2018-07-01

    Cancer treatment may lead to premature menopause and infertility. Young adult female cancer survivors (YAFCS) are often concerned about their fertility and future family-building options, but research is limited on how concerns may affect more general quality of life (QOL) domains. This study examined how fertility factors relate to QOL among YAFCS who received gonadotoxic therapy. A national sample of YAFCS completed an online, anonymous survey. The survey included investigator-designed questions about perceived fertility information needs (five items; Cronbach's α = .83) and general QOL (four items; α = .89), the Reproductive Concerns after Cancer Scale (RCACS) and Decisional Conflict Scale (DCS). Analyses included Pearson's correlation, t tests, and stepwise regression. Participants (N = 314) were an average of 30 years old (SD = 4.1) and 5 years (SD = 5.4) post-treatment; 31% reported being infertile and 19% had undergone fertility preservation (FP). Overall, QOL was relatively high (M = 7.3, SD = 1.9, range 0-10) and did not vary by fertility status (t[272] = .743, p = .46), prior FP (t[273] = .53, p = .55) or sociodemographic/clinical factors (p's > .05) except socioeconomic indicators (p's < .05).In separate models, greater unmet fertility information needs (β = - .19, p = .004) and, among fertile women, greater reproductive concerns (β = - .26, p = .001) related to lower QOL. Among fertile women without prior FP, greater decisional distress about future FP related to lower QOL (β = - .19, p = .03). These preliminary findings suggest that unaddressed fertility information needs, concerns, and decision distress may affect general QOL among post-treatment YAFCS who hope to have children in the future. Future work should identify ways to optimally incorporate fertility counseling and support resources into survivorship care programs, including referrals to reproductive

  6. On low fertility from the aspect of the economic activity of female population: Possibilities and restrictions in encouragement of childbearing

    Directory of Open Access Journals (Sweden)

    Šobot Ankica

    2014-01-01

    Full Text Available Below replacement fertility was the outcome of changes in the education and socio-professional structure of women, as well as modifications in values and life aspirations. On the other hand, economic strengthening of women and encourage-ment of jobs which require greater dedication and more of their time are important aspects of achieving gender equality. These two circumstances gave rise to contemplations on the connection between economic activities of female population and the level of births in postindustrial societies. The aim of this article is to point out to the positive influence of female employment on the fertility level, as a capacity for encouraging births in Serbia. When observing the most developed European countries, it can be noticed that greater birth rates are noted in those countries in which there are greater economic activity and employment rates of female population. Furthermore, a series of researches and comparative analyses confirm the positive relation between female employment and fertility. The differences regarding of birth rates among European welfare states are seen as a result of the possibilities of female employment, reconciliation between work and parenthood and the division of gender roles within the family. The influence of economic activity on fertility levels is determined by an institutional framework of family support and gender equality (Engelhardt and Prskawetz, 2004, Neyer, 2006; Andersson and Scott, 2007; Rovny, A.E. 2011; Seeleib-Kaise and Toivonen, 2011. During the first decade of the 21st century, the birth rates in Serbia were by about 30% lower than in the countries which had the highest fertility within European frameworks. The traditional labor division in the household and parenthood produces conflicts between families and employment, recognized in the practices of everyday life (Blagojević, 1997; Blagojević-Hjuson, 2013 and standpoints on the relation between parenthood and employment

  7. Multivariate Cholesky models of human female fertility patterns in the NLSY.

    Science.gov (United States)

    Rodgers, Joseph Lee; Bard, David E; Miller, Warren B

    2007-03-01

    Substantial evidence now exists that variables measuring or correlated with human fertility outcomes have a heritable component. In this study, we define a series of age-sequenced fertility variables, and fit multivariate models to account for underlying shared genetic and environmental sources of variance. We make predictions based on a theory developed by Udry [(1996) Biosocial models of low-fertility societies. In: Casterline, JB, Lee RD, Foote KA (eds) Fertility in the United States: new patterns, new theories. The Population Council, New York] suggesting that biological/genetic motivations can be more easily realized and measured in settings in which fertility choices are available. Udry's theory, along with principles from molecular genetics and certain tenets of life history theory, allow us to make specific predictions about biometrical patterns across age. Consistent with predictions, our results suggest that there are different sources of genetic influence on fertility variance at early compared to later ages, but that there is only one source of shared environmental influence that occurs at early ages. These patterns are suggestive of the types of gene-gene and gene-environment interactions for which we must account to better understand individual differences in fertility outcomes.

  8. The Trade-Off between Female Fertility and Longevity during the Epidemiological Transition in the Netherlands

    DEFF Research Database (Denmark)

    Kaptijn, Ralf; Thomese, Fleur; Liefbroer, Aart C

    2015-01-01

    as an evolutionary trade-off between reproduction and survival. We examine the relationship between fertility and longevity during the epidemiological transition in the Netherlands. This period of rapid decline in mortality from infectious diseases offers a good opportunity to study the relationship between...... fertility and longevity, using registry data from 6,359 women born in The Netherlands between 1850 and 1910. We hypothesize that an initially negative relationship between women's fertility and their longevity gradually turns less negative during the epidemiological transition, because of decreasing costs...

  9. Awareness, knowledge, and perceptions of infertility, fertility assessment, and assisted reproductive technologies in the era of oocyte freezing among female and male university students.

    Science.gov (United States)

    Meissner, C; Schippert, C; von Versen-Höynck, Frauke

    2016-06-01

    The aims of our study were to analyze university student's knowledge and attitude towards parenthood, female fertility, fertility assessment, and oocyte freezing and to explore associations between these aspects and the participant's sex or degree program they were registered for. The study was designed as an online-based cross-sectional survey. A total of 1144 participants answered 27 questions. The data were analyzed using descriptive statistics. Linear regression models were employed to explore associations between sex or university program and attitude towards parenthood, fertility assessment, and oocyte freezing. Female students and students of non-medical degree programs were more likely to plan to have children earlier than male students or students of medical degree programs. Female sex or medical degree program was associated with an overall better knowledge about women's fertility. The better the participant's knowledge about fertility, the more likely the students would consider assisted reproductive technology (ART) treatments as an option to become pregnant when ovarian reserve is low. The majority of students knew the principal of oocyte freezing but would not consider using it. However, in the case of a low ovarian reserve, oocyte freezing would be accepted as an option. Students planned to have children at an age when women's fertility is already declining. Gaps in knowledge about female fertility and the potential of ART were more pronounced in male students and students of non-medical degree programs suggesting an increase of fertility awareness is necessary in these groups to prevent them from infertility and unwanted childlessness.

  10. Which female cancer patients fail to receive fertility counseling before treatment in the state of Georgia?

    Science.gov (United States)

    Chin, Helen B; Howards, Penelope P; Kramer, Michael R; Mertens, Ann C; Spencer, Jessica B

    2016-12-01

    To assess which characteristics are associated with failure to receive fertility counseling among a cohort of young women diagnosed with cancer. Population-based cohort study. Not applicable. A total of 1,282 cancer survivors, of whom 1,116 met the inclusion criteria for the analysis. None. The main outcome in this study was whether or not women reported receiving any information at the time of their cancer diagnosis on how cancer treatment might affect their ability to become pregnant. Forty percent of cancer survivors reported that they did not receive fertility counseling at the time of cancer diagnosis. Women were more likely to fail to receive counseling if they had only a high school education or less or if they had given birth. Cancer-related variables that were associated with a lack of counseling included not receiving chemotherapy as part of treatment and diagnosis with certain cancer types. Counseling about the risk of infertility and available fertility preservation options is important to cancer patients. Additionally, counseling can make women aware of other adverse reproductive outcomes, such as early menopause and its associated symptoms. Less-educated women and parous women are at particular risk of not getting fertility-related information. Programs that focus on training not just the oncologist, but also other health care providers involved with cancer care, to provide fertility counseling may help to expand access. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Consequences of hyperthyroidism in male and female fertility: pathophysiology and current management.

    Science.gov (United States)

    Mintziori, G; Kita, M; Duntas, L; Goulis, D G

    2016-08-01

    Thyroid hormone acts on the oocytes, sperm and embryo during fertilization, implantation and placentation. Both hypothyroidism and hyperthyroidism may influence fertility. However, evidence of the association of hyperthyroidism with infertility is scarce and sometimes conflicting. Thyroid hormone influences human reproduction via a variety of mechanisms at both the central and the peripheral level. Infertility may occur in hyperthyroid men and women, but it is usually reversible upon restoration of euthyroidism. This review aims to summarize the available data on the association of hyperthyroidism and infertility in both men and women and to provide practical suggestions for the management of these patients.

  12. Cryopreservation of ovarian tissue for fertility preservation in young female oncological patients

    DEFF Research Database (Denmark)

    Andersen, Claus Yding; Kristensen, Stine Gry; Greve, Tine

    2012-01-01

    Girls and women suffering from a cancer that requires treatment with gonadotoxic drugs may experience cessation of reproductive function as a side effect due to obliteration of the ovarian pool of follicles. Techniques are now available for fertility preservation, such as cryopreservation of mature...... and growth of follicles, giving rise to menstrual cycles and hormone production for several years. Worldwide, the procedure has resulted in the birth of 15 healthy children. Many cancer patients including girls and young women want fertility preservation, and the techniques are now being further developed...

  13. Case series of fertility treatment in HIV-discordant couples (male positive, female negative: the Ontario experience.

    Directory of Open Access Journals (Sweden)

    Trent Newmeyer

    Full Text Available The success of combination antiretroviral therapies for the treatment of human immunodeficiency virus (HIV has resulted in prolonged life expectancy (over 40 years from diagnosis and an improved quality of life for people living with HIV. The risk of vertical HIV transmission during pregnancy has been reduced to less than 1%. As a result of these breakthroughs and as many of these individuals are of reproductive age, fertility issues are becoming increasingly important for this population. One population in which conception planning and reduction of horizontal HIV transmission warrants further research is HIV-discordant couples where the male partner is HIV-positive and the female partner is HIV-negative. Sperm washing is a technique carried out in a fertility clinic that separates HIV from the seminal fluid. Although sperm washing followed by intrauterine insemination significantly reduces the risk of horizontal HIV transmission, there has been limited access to the procedure in North America. Furthermore, little is known about the conception decision-making experiences of HIV-discordant couples who might benefit from sperm washing. Chart reviews and semi-structured interviews were completed with 12 HIV-discordant couples in Ontario, Canada. Couples were recruited through HIV clinics and one fertility clinic that offered sperm washing. Participants identified a number of factors that affected their decision-making around pregnancy planning. Access to sperm washing and other fertility services was an issue (cost, travel and few clinics. Participants identified a lack of information on the procedure (availability, safety. Sources of support (social networks, healthcare providers were unevenly distributed, especially among those who did not disclose their HIV status to friends and family. Finally, the stigmatisation of HIV continues to have a negative affect on HIV-discordant couples and their intentions to conceive. Access to sperm washing and

  14. Improving patient-centredness in partnership with female patients: a cluster RCT in fertility care

    NARCIS (Netherlands)

    Huppelschoten, A.G.; Nelen, W.L.D.M.; Westert, G.P.; Golde, R.J.T. van; Adang, E.M.M.; Kremer, J.A.M.

    2015-01-01

    QUESTION: What is the effect of a multifaceted intervention with participation of patients on improvement of patient-centredness in fertility care? SUMMARY ANSWER: A multifaceted intervention with participation of patients did not improve total patient-centredness scores provided by women in

  15. Should access to fertility treatment be determined by female body mass index?

    Science.gov (United States)

    Pandey, S; Maheshwari, A; Bhattacharya, S

    2010-04-01

    Resource allocation towards fertility treatment has been extensively debated in countries where fertility treatment is publicly-funded. Medical, social and ethical aspects have been evaluated prior to allocation of resources. Analysis of cost-effectiveness, risks and benefits and poor success rates have led to calls of restricting fertility treatment to obese women. In this debate article, we critically appraise the evidence underlying this issue and highlight the problems with such a policy. Poor success rate of treatment is unsubstantiated as there is insufficient evidence to link high body mass index (BMI) to reduction in live birth. Obstetric complications have a linear relationship with BMI but are significantly influenced by maternal age. The same is true for miscarriage rates which are influenced by the confounding factors of polycystic ovary syndrome and age. Studies have shown that the direct costs per live birth are no greater for overweight and obese women. With changing demographics over half the reproductive-age population is overweight or obese. Restricting fertility treatment on the grounds of BMI would cause stigmatization and lead to inequity, feelings of injustice and social tension as affluent women manage to bypass these draconian restrictions. Time lost and poor success of conventional weight loss strategies would jeopardize the chances of conception for many women.

  16. Identification of Phytophthora sojae genes involved in asexual ...

    Indian Academy of Sciences (India)

    ual sporulation or germination. But molecular details about asexual spore development in P. sojae are limited (Tyler et al. 2006). In the present study, to understand the molecular basis of asexual spore development in P. sojae, we investigated gene expression changes involved in asexual sporulation after ul- traviolet (UV) ...

  17. Origins of asexuality in Bryobia mites (Acari: Tetranychidae)

    NARCIS (Netherlands)

    Ros, V.I.D.; Breeuwer, J.A.J.; Menken, S.B.J.

    2008-01-01

    Background Obligate asexual reproduction is rare in the animal kingdom. Generally, asexuals are considered evolutionary dead ends that are unable to radiate. The phytophagous mite genus Bryobia contains a large number of asexual species. In this study, we investigate the origin and evolution of

  18. Morphological peculiarities of bryophytes asexual organs

    Directory of Open Access Journals (Sweden)

    Oksana Lobachevska

    2013-04-01

    Full Text Available The main types of brood organs of dominant bryophyte species on dumps of the mining factories were determined. The special features of morphology, localization and genesis of specialized asexual propagula and gemmae were detected. The analysis of their role in reproductive strategy of colonist species was conducted.

  19. Young female cancer patients' experiences with fertility counselling and fertility preservation-a qualitative small-scale study within the Danish health care setting.

    Science.gov (United States)

    Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T

    2016-07-14

    Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before initiation of cancer treatment. Participants were interviewed at a place chosen by them, and interviews were recorded and transcribed verbatim. Data were analysed using systematic text condensation developed by Malterud and inspired by Giorgi's phenomenological analysis. None of the participants were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how the possibility of fertility preservation removed a huge concern and enabled them to concentrate on their cancer treatment and on getting better. Overall, the specialized fertility counselling and treatment to preserve fertility was highly valued. The women felt it gave them a choice about their future fertility. The fertility expert presented the various fertility-preserving scenarios, and the women were content that they had an actual choice.

  20. Young female cancer patients’ experiences with fertility counselling and fertility preservation—a qualitative small-scale study within the Danish health care setting

    Science.gov (United States)

    Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T.

    2016-01-01

    Introduction Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Methods Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before initiation of cancer treatment. Participants were interviewed at a place chosen by them, and interviews were recorded and transcribed verbatim. Data were analysed using systematic text condensation developed by Malterud and inspired by Giorgi’s phenomenological analysis. Results None of the participants were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how the possibility of fertility preservation removed a huge concern and enabled them to concentrate on their cancer treatment and on getting better. Conclusion Overall, the specialized fertility counselling and treatment to preserve fertility was highly valued. The women felt it gave them a choice about their future fertility. The fertility expert presented the various fertility-preserving scenarios, and the women were content that they had an actual choice. PMID:27413812

  1. Cryopreservation of ovarian tissue for fertility preservation in young female oncological patients.

    Science.gov (United States)

    Andersen, Claus Yding; Kristensen, Stine Gry; Greve, Tine; Schmidt, Kirsten Tryde

    2012-05-01

    Girls and women suffering from a cancer that requires treatment with gonadotoxic drugs may experience cessation of reproductive function as a side effect due to obliteration of the ovarian pool of follicles. Techniques are now available for fertility preservation, such as cryopreservation of mature oocytes, embryos or ovarian cortical tissue. Whereas collection of mature oocytes and embryos requires at least a 2-week period, ovarian tissue may on short notice be frozen prior to treatment and can be transplanted back into women with ovarian failure. Transplanted frozen/thawed tissue supports survival and growth of follicles, giving rise to menstrual cycles and hormone production for several years. Worldwide, the procedure has resulted in the birth of 15 healthy children. Many cancer patients including girls and young women want fertility preservation, and the techniques are now being further developed and implemented in several centers.

  2. Cold-shock eliminates female nucleus in fertilized eggs to induce androgenesis in the loach (Misgurnus anguillicaudatus, a teleost fish

    Directory of Open Access Journals (Sweden)

    Morishima Kagayaki

    2011-11-01

    Full Text Available Abstract Background Androgenesis (all-male inheritance is generally induced by means of irradiating the eggs to inactivate the maternal genome, followed by fertilization with normal sperm. In fish, the conventional technique for induced androgenesis has been applied for rapid fixation to traits, recovery of cryopreserved genotypes, sex-control, etc. A new method of androgenesis that eliminates the need to irradiate the egg was proposed using the loach, Misgurnus anguillicaudatus (a teleost fish. Results When the eggs of wild-type females were fertilized with sperm of albino or orange phenotype males and cold-shocked at 0 to 3°C for 60 min duration just after fertilization, generally more than 30% (with a peak of 100% of the hatched progeny were androgenotes. While a few of them were the normal diploid, most of them turned out to be abnormal haploid. All-male inheritance was verified by the expression of the recessive color trait (albino or orange and microsatellite genotypes comprising only paternally derived alleles. Nuclear behavior after the cold-shock treatment was traced by microscopic observation of DAPI (4'6-diamidino-2-phenylindole-stained samples and hematoxylin-eosin stained histological sections, and the extrusion of egg (maternal nucleus was observed in eggs treated in the optimum timing. Conclusion In this paper, we demonstrate that cold-shock treatment (at 0 and 3°C of loach eggs for 60 min just after fertilization successfully induces androgenetic haploid development. The most likely mechanism of cold-shock induced androgenesis is an elimination of the egg nucleus together along with the second polar body and subsequent development of a decondensed sperm nucleus or male pronucleus.

  3. inter-fertility among female parent clones of pineapple involved in a ...

    African Journals Online (AJOL)

    ACSS

    Ivoireconsiders fruit diversification as key component in the international pineapple industry. The objective of this study was to determine the sexual compatibility of female pineapple clones recently developed in Côte d'Ivoire. Three female hybrid clones, ...

  4. Beta-Thalassemia Major and Female Fertility: The Role of Iron and Iron-Induced Oxidative Stress

    Science.gov (United States)

    Roussou, Paraskevi; Tsagarakis, Nikolaos J.; Diamanti-Kandarakis, Evanthia

    2013-01-01

    Endocrine complications due to haemosiderosis are present in a significant number of patients with beta-thalassemia major (BTM) worldwide and often become barriers in their desire for parenthood. Thus, although spontaneous fertility can occur, the majority of females with BTM is infertile due to hypogonadotropic hypogonadism (HH) and need assisted reproductive techniques. Infertility in these women seems to be attributed to iron deposition and iron-induced oxidative stress (OS) in various endocrine organs, such as hypothalamus, pituitary, and female reproductive system, but also through the iron effect on other organs, such as liver and pancreas, contributing to the impaired metabolism of hormones and serum antioxidants. Nevertheless, the gonadal function of these patients is usually intact and fertility is usually retrievable. Meanwhile, a significant prooxidants/antioxidants imbalance with subsequent increased (OS) exists in patients with BTM, which is mainly caused by tissue injury due to overproduction of free radicals by secondary iron overload, but also due to alteration in serum trace elements and antioxidant enzymes. Not only using the appropriate antioxidants, essential trace elements, and minerals, but also regulating the advanced glycation end products, could probably reduce the extent of oxidative damage and related complications and retrieve BTM women's infertility. PMID:24396593

  5. Maternal MEMI Promotes Female Meiosis II in Response to Fertilization in Caenorhabditis elegans.

    Science.gov (United States)

    Ataeian, Maryam; Tegha-Dunghu, Justus; Curtis, Donna G; Sykes, Ellen M E; Nozohourmehrabad, Ashkan; Bajaj, Megha; Cheung, Karen; Srayko, Martin

    2016-12-01

    In most animals, female meiosis completes only after fertilization. Sperm entry has been implicated in providing a signal for the initiation of the final meiotic processes; however, a maternal component required for this process has not been previously identified. We report the characterization of a novel family of three highly similar paralogs (memi-1, memi-2, memi-3) that encode oocyte-specific proteins. A hyper-morphic mutation memi-1(sb41) results in failure to exit female meiosis II properly; however, loss of all three paralogs results in a "skipped meiosis II" phenotype. Mutations that prevent fertilization, such as fer-1(hc1), also cause a skipped meiosis II phenotype, suggesting that the MEMI proteins represent a maternal component of a postfertilization signal that specifies the meiosis II program. MEMI proteins are degraded before mitosis and sensitive to ZYG-11, a substrate-specific adapter for cullin-based ubiquitin ligase activity, and the memi-1(sb41) mutation results in inappropriate persistence of the MEMI-1 protein into mitosis. Using an RNAi screen for suppressors of memi-1(sb41), we identified a sperm-specific PP1 phosphatase, GSP-3/4, as a putative sperm component of the MEMI pathway. We also found that MEMI and GSP-3/4 proteins can physically interact via co-immunoprecipitation. These results suggest that sperm-specific PP1 and maternal MEMI proteins act in the same pathway after fertilization to facilitate proper meiosis II and the transition into embryonic mitosis. Copyright © 2016 by the Genetics Society of America.

  6. Mlh1 is required for female fertility in Drosophila melanogaster: An outcome of effects on meiotic crossing over, ovarian follicles and egg activation.

    Science.gov (United States)

    Vimal, Divya; Kumar, Saurabh; Pandey, Ashutosh; Sharma, Divya; Saini, Sanjay; Gupta, Snigdha; Ravi Ram, Kristipati; Chowdhuri, Debapratim Kar

    2018-03-01

    Mismatch repair (MMR) system, a conserved DNA repair pathway, plays crucial role in DNA recombination and is involved in gametogenesis. The impact of alterations in MMR family of proteins (bacterial MutS and MutL homologues) on mammalian fertility is well documented. However, an insight to the role of MMR in reproduction of non-mammalian organisms is limited. Hence, in the present study, we analysed the impact of mlh1 (a MutL homologue) on meiotic crossing over/recombination and fertility in a genetically tractable model, Drosophila melanogaster. Using mlh1 e00130 hypomorphic allele, we report female specific adverse reproductive outcome for reduced mlh1 in Drosophila: mlh1 e00130 homozygous females had severely reduced fertility while males were fertile. Further, mlh1 e00130 females contained small ovaries with large number of early stages as well as significantly reduced mature oocytes, and laid fewer eggs, indicating discrepancies in egg production and ovulation. These observations contrast the sex independent and/or male specific sterility and normal follicular development as well as ovulation reported so far for MMR family proteins in mammals. However, analogous to the role(s) of mlh1 in meiotic crossing over and DNA repair processes underlying mammalian fertility, ovarian follicles from mlh1 e00130 females contained significantly increased DNA double strand breaks (DSBs) and reduced synaptonemal complex foci. In addition, large proportion of fertilized eggs display discrepancies in egg activation and fail to proceed beyond stage 5 of embryogenesis. Hence, reduction of the Mlh1 protein level leads to defective oocytes that fail to complete embryogenesis after fertilization thereby reducing female fertility. Copyright © 2017 Elsevier GmbH. All rights reserved.

  7. PRELIMINARY CLINICAL OBSERVATIONS ON THE GINGIVAL-PERIODONTAL MANIFESTATIONS IN IN VITRO FERTILIZED FEMALE PATIENTS

    Directory of Open Access Journals (Sweden)

    Ana GIURA

    2012-06-01

    Full Text Available Scope of the study – determination of the types and intensity of the gingival-periodontal manifestations in in vitro fertilized pregnant women, and establishment of the role played by the hormonal treatment in the initiation and maintenance of such manifestations. Materials and method. The study was performed on patients fertilized in vitro between the years 2010-2012, in the Section of Assisted Human Reproduction of the “Panait Sârbu” Clinical Hospital of Obstretics and Ginecology – Bucuresti. All patients received the same amount and concentration of progesteronic compounds for maintaining their state of pregnancy, being examined in the first gestation weeks, immediately after confirmation of pregnancy through the β-hCG blood test. Results anddiscussion: In the last decades, the effects of estrogen and progesterone have drawn special attention from the part of the researchers. During pregnancy, the gingiva represents the maintissular target for the action of steroid hormones. Pregnancy-induced gingivitis is directly correlated with the presence of the microbial flora, known as the determining factor of the disease, being still exacerbated by the action of the sexual hormones, especially during the second and third quarter of pregnancy. Conclusions: The influence of gestational hormones upon the immune system of the organism may further contribute to the initiation and worsening of pregnancy-induced gingivitis, by reducing the immune response vs. the bacterial plaque.

  8. Public goods dilemma in asexual ant societies

    OpenAIRE

    Dobata, Shigeto; Tsuji, Kazuki

    2013-01-01

    This study reports experimental evidence for the “public goods dilemma” between cooperators and cheaters in an asexual ant society, in which cheating is always more rewarding for individuals but cooperation at the cost of individual fitness leads to better performance of groups. Although this dilemma provides the basic principle of social evolution, its experimental demonstration with underlying genetics and fitness evaluation for both cooperators and cheaters still lacks in societies other t...

  9. The role of anti-Müllerian hormone in female fertility and infertility - an overview

    DEFF Research Database (Denmark)

    Grynnerup, Anna Garcia-Alix; Lindhard, Anette; Sørensen, Steen

    2012-01-01

    and hyper-responses. However, recent research has also highlighted the use of AMH in a variety of ovarian pathological conditions, including polycystic ovary syndrome, granulosa cell tumors and premature ovarian failure. A new commercial enzyme-linked immunosorbent assay for measuring AMH levels has been......Anti-Müllerian hormone (AMH) plasma levels reflect the continuous non-cyclic growth of small follicles, thereby mirroring the size of the resting primordial follicle pool and thus acting as a useful marker of ovarian reserve. Anti-Müllerian hormone seems to be the best endocrine marker...... for assessing the age-related decline of the ovarian pool in healthy women; thus, it has a potential ability to predict future reproductive lifespan. The most established role for AMH measurements is before in vitro fertilization is initiated, because AMH can be predictive of the ovarian response, namely poor...

  10. Identification of Common Genetic Variants Influencing Spontaneous Dizygotic Twinning and Female Fertility

    Science.gov (United States)

    Mbarek, Hamdi; Steinberg, Stacy; Nyholt, Dale R.; Gordon, Scott D.; Miller, Michael B.; McRae, Allan F.; Hottenga, Jouke Jan; Day, Felix R.; Willemsen, Gonneke; de Geus, Eco J.; Davies, Gareth E.; Martin, Hilary C.; Penninx, Brenda W.; Jansen, Rick; McAloney, Kerrie; Vink, Jacqueline M.; Kaprio, Jaakko; Plomin, Robert; Spector, Tim D.; Magnusson, Patrik K.; Reversade, Bruno; Harris, R. Alan; Aagaard, Kjersti; Kristjansson, Ragnar P.; Olafsson, Isleifur; Eyjolfsson, Gudmundur Ingi; Sigurdardottir, Olof; Iacono, William G.; Lambalk, Cornelis B.; Montgomery, Grant W.; McGue, Matt; Ong, Ken K.; Perry, John R.B.; Martin, Nicholas G.; Stefánsson, Hreinn; Stefánsson, Kari; Boomsma, Dorret I.

    2016-01-01

    Spontaneous dizygotic (DZ) twinning occurs in 1%–4% of women, with familial clustering and unknown physiological pathways and genetic origin. DZ twinning might index increased fertility and has distinct health implications for mother and child. We performed a GWAS in 1,980 mothers of spontaneous DZ twins and 12,953 control subjects. Findings were replicated in a large Icelandic cohort and tested for association across a broad range of fertility traits in women. Two SNPs were identified (rs11031006 near FSHB, p = 1.54 × 10−9, and rs17293443 in SMAD3, p = 1.57 × 10−8) and replicated (p = 3 × 10−3 and p = 1.44 × 10−4, respectively). Based on ∼90,000 births in Iceland, the risk of a mother delivering twins increased by 18% for each copy of allele rs11031006-G and 9% for rs17293443-C. A higher polygenic risk score (PRS) for DZ twinning, calculated based on the results of the DZ twinning GWAS, was significantly associated with DZ twinning in Iceland (p = 0.001). A higher PRS was also associated with having children (p = 0.01), greater lifetime parity (p = 0.03), and earlier age at first child (p = 0.02). Allele rs11031006-G was associated with higher serum FSH levels, earlier age at menarche, earlier age at first child, higher lifetime parity, lower PCOS risk, and earlier age at menopause. Conversely, rs17293443-C was associated with later age at last child. We identified robust genetic risk variants for DZ twinning: one near FSHB and a second within SMAD3, the product of which plays an important role in gonadal responsiveness to FSH. These loci contribute to crucial aspects of reproductive capacity and health. PMID:27132594

  11. Prenatal maternal effects on body condition score, female fertility, and milk yield of dairy cows.

    Science.gov (United States)

    Banos, G; Brotherstone, S; Coffey, M P

    2007-07-01

    In this study, maternal effects were described as age of dam at first and second calving, first-lactation body condition score (BCS) of the dam during gestation, and milk yield of the dam. The impact of these effects on first-lactation daughter BCS, fertility, and test-day milk yield was assessed. The effect of milk yield of dam on daughter 305-d yield in the latter's first 3 lactations was also investigated. The proportion of total phenotypic variance in daughter traits accounted for by maternal effects was calculated. Dams calving early for the first time (18 to 23 mo of age) had daughters that produced 4.5% more first-lactation daily milk, had 7% higher BCS, and had their first service 3 d earlier than cows whose dams calved late (30 to 36 mo). However, daughters of dams that calved early had difficulties conceiving as they needed 7% more inseminations and had a 7.5% higher return rate. Cows from second calvings of relatively young (36 to 41 mo) dams produced 6% more first-lactation daily milk, had 2% higher BCS, and showed a significantly better fertility profile than cows whose dams calved at a late age (47 to 55 mo). High maternal BCS during gestation had a favorable effect on daughter BCS, nonreturn rate, and number of inseminations per conception. However, it was also associated with a small decrease in daughter daily milk yield. Changes in dam BCS during gestation did not affect daughter performance significantly. Maternal effects of milk yield of the dam, expressed as her permanent environment during lactation, adversely affected daughter 305-d milk, fat, and protein yield. However, although the effect was significant, it was practically negligible (<0.3% of the mean). Finally, overall maternal effects accounted for a significant proportion of the total phenotypic variance of calving interval (1.4 +/- 0.6%) and nonreturn rate (1.1 +/- 0.5%).

  12. Effects of lung exposure to carbon nanotubes on female fertility and pregnancy. A study in mice

    DEFF Research Database (Denmark)

    Hougaard, Karin S.; Jackson, Petra; Kyjovska, Zdenka O.

    2013-01-01

    We studied the effects of preconceptional exposure to multiwalled carbon nanotubes (MWCNTs): mature, female C57BL/6J mice were intratracheally instilled with 67μg NM-400 MWCNT, and the following day co-housed with mature males, in breeding pairs. Time to delivery of the first litter, litter...

  13. Genetic parameters for reproductive traits in female Nile tilapia (Oreochromis niloticus): II. Fecundity and fertility

    NARCIS (Netherlands)

    Trong, T.Q.; Arendonk, van J.A.M.; Komen, J.

    2013-01-01

    Harvest weight is the main trait in Nile tilapia (Oreochromis niloticus) breeding programmes. The effects of selection for harvest weight on female reproductive traits are unknown. In this paper we estimate genetic parameters for reproductive traits and their correlation with harvest weight using

  14. Young female cancer patients? experiences with fertility counselling and fertility preservation?a qualitative small-scale study within the Danish health care setting

    OpenAIRE

    Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T.

    2016-01-01

    Introduction Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Methods Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselli...

  15. Detailed clinical and molecular study of 20 females with Xq deletions with special reference to menstruation and fertility.

    Science.gov (United States)

    Mercer, Catherine L; Lachlan, Katherine; Karcanias, Alexandra; Affara, Nabeel; Huang, Shuwen; Jacobs, Patricia A; Thomas, N Simon

    2013-01-01

    Integrity of the long arm of the X chromosome is important for maintaining female fertility and several critical regions for normal ovarian function have been proposed. In order to understand further the importance of specific areas of the X chromosome, we describe a series of 20 previously unreported patients missing part of Xq in whom detailed phenotypic information has been gathered as well as precise chromosome mapping using array Comparative Genomic Hybridization. Features often associated with Turner syndrome were not common in our study and excluding puberty, menarche and menstruation, the phenotypes observed were present in only a minority of women and were not specific to the X chromosome. The most frequently occurring phenotypic features in our patients were abnormalities of menstruation and fertility. Larger terminal deletions were associated with a higher incidence of primary ovarian failure, occurring at a younger age; however patients with similar or even identical deletions had discordant menstrual phenotypes, making accurate genetic counselling difficult. Nevertheless, large deletions are likely to be associated with complete skewing of X inactivation so that the resulting phenotypes are relatively benign given the amount of genetic material missing, even in cases with unbalanced X;autosome translocations. Some degree of ovarian dysfunction is highly likely, especially for terminal deletions extending proximal to Xq27. In conjunction with patient data from the literature, our study suggests that loss of Xq26-Xq28 has the most significant effect on ovarian function. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  16. Birth Order and Sibling Sex Ratio in a Population with High Fertility: Are Turkish Male to Female Transsexuals Different?

    Science.gov (United States)

    Bozkurt, Ali; Bozkurt, Ozlem Hekim; Sonmez, Ipek

    2015-07-01

    Western studies have consistently found that androphilic (sexually attracted to men) male-to-female transsexuals have a later birth order and a relative excess of brothers compared with appropriate control participants. However, non-Western studies on birth order and sibling sex ratio in androphilic males (transsexual or non-transsexual) are rare. The objective of the study was to test the hypothesis that androphilic male-to-female transsexuals have a late birth order and a relative excess of brothers in a non-Western culture with a higher fertility rate. The participants were 60 androphilic male-to-female transsexuals and 61 male heterosexual controls. The transsexual participants had significantly more older brothers than the control participants, but the groups did not differ in their numbers of older sisters, younger brothers, or younger sisters. The foregoing pattern is usually referred to as the "fraternal birth order effect." Slater's and Berglin's Indexes both showed that the mean birth order of the control participants was very close to that expected from a random sample drawn from a demographically stable population whereas the mean birth order of the transsexual participants was later. A measure of sibship composition, brothers/all siblings, showed that the transsexual group had a higher proportion of male siblings compared with the control group. In conclusion, the present study found that Turkish androphilic male-to-female transsexuals show the same high fraternal birth order that has been found in comparable androphilic samples in Western Europe, North America, and the South Pacific, which suggests a common underlying biological causal mechanism.

  17. Genome-wide association study for female fertility in Nordic Red cattle

    DEFF Research Database (Denmark)

    Höglund, Johanna; Buitenhuis, Albert Johannes; Guldbrandtsen, Bernt

    2015-01-01

    cattle. The sub-traits of FTI are: number of inseminations per conception (AIS) in cows (C) and heifers (H), the length in days of the interval from calving to first insemination (ICF) in cows, days from first to last insemination (IFL) in cows and heifers, and 56-day non-return rate (NRR) in cows...... and heifers. The aim of this study was first to identify QTL for FTI by conducting a genome scan for variants associated with fertility index using imputed whole genome sequence data based on 4207 Nordic Red sires, and subsequently analyzing which of the sub-traits were affected by each FTI QTL by associating......). Conclusion This study 1) shows that many markers within FTI QTL regions were significantly associated with both AISH and IFLH, and 2) identified candidate genes for FTI located on BTA6 (GPR125), BTA13 (ANKRD60), BTA15 (GRAMD1B), and BTA24 (ZNF521). It is not known how the genes/variants identified...

  18. Female infertility in India: Causes, treatment and impairment of fertility in selected districts with high prevalence

    Directory of Open Access Journals (Sweden)

    Shraboni Patra

    2017-01-01

    Full Text Available Although the ‘universal access to sexual and reproductive health care’ has received priority in the SDG‐3, the rural women experiencing infertility problem in India are unable to access and afford quality reproductive health care. The study investigates the present infertility situation, with a focus on risk factors, treatment seeking for infertility, and impact of infertility on fertility in India and its districts with high infertility prevalence. The DLHS‐3 data is used. Top fifteen districts with high infertility prevalence are selected for analysis. Simple bivariate and multivariate techniques are applied. In India, the prevalence of ever‐experienced primary, secondary, and current infertility is 6.6%, 2.1% and 4.6% respectively, whereas, in the selected districts, the estimates for the same indicators are 15%, 3.1%, and 5% respectively. A higher prevalence of reported symptoms of RTIs/STIs and menstrual problems is observed among women who ever had infertility. Treatment seeking for infertility is low in Korba and Koryia. The MCEB is less among women who ever had experienced infertility. The prevalence of ever‐experienced infertility and current infertility is considerably higher among women from socio‐economically disadvantaged sections. Awareness of RTIs, STIs, and menstrual problems, and preventive care can reduce infertility among rural women.

  19. [Artistic representation of the female breast as an attribute of femininity and fertility and also the origin of life force and wisdom].

    Science.gov (United States)

    Kirchhoff, H

    1990-03-01

    The artistic representation of the female breasts is based upon two totally independent concepts, which are different in their expression. On the one hand, the figure, clasping her hands around her breasts, stands for womanliness and fertility. On the other hand, the act of voiding milk or water, symbolizes donation of or wisdom. These two functions of the female breasts are a large number of illustrations.

  20. Genetic parameters for body weight ratio, fertility and growth traits in Canchim breed females

    Directory of Open Access Journals (Sweden)

    Silvio de Paula Mello

    2013-03-01

    Full Text Available The objective of this study was to estimate the heritability of age at first calving (AFC, body condition score at first calving (BCF, body condition score at calving (BCC, weaning weight (WW, yearling weight (W12, weaning weight of calf/weight of cow at calving (RCC and weaning weight of first calf/weight of cow at first calving (RCCF ratios, and genetic correlations of AFC, BCF, WW and W12 with RCCF, in a Canchim beef cattle herd. The variance and covariance components were obtained by bayesian inference with single and two-trait analyses. The statistical models included the additive direct and maternal, the permanent environmental and the residual random effects, and the fixed effects of year and month of birth or of calving, age of cow at calving and sex of calf, depending on the trait. The posterior means of heritability, obtained by single-trait analyses, were 0.12 (AFC, 0.36 (BCF, 0.18 (BCC, 0.50 (WW, 0.46 (W12, 0.16 (RCC and 0.40 (RCCF indicating that these traits have enough genetic variability to  show response to mass selection with the exception of AFC. The genetic correlations of AFC (-0.61, BCF (-0.36, WW (-0.20 and W12 (-0.05 with RCCF suggest that selection to reduce age and body condition score at first calving should improve the productivity trait of females at first calving, while selection for heavier females at young ages would not promote any change in the productivity of dams.

  1. Identification of genomic regions associated with female fertility in Danish Jersey using whole genome sequence data

    DEFF Research Database (Denmark)

    Höglund, Johanna; Guldbrandtsen, Bernt; Lund, Mogens Sandø

    2015-01-01

    6 QTL were detected for FTI: one QTL on each of BTA7, BTA20, BTA23, BTA25, and two QTL on BTA9 (QTL9–1 and QTL9–2). In the second step, ICF showed association with the QTL regions on BTA7, QTL9–2 QTL2 on BTA9, and BTA25, AIS for cows on BTA20 and BTA23, AIS for heifers on QTL9–2 on BTA9, IFL...... for cows on BTA20, BTA23 and BTA25, IFL for heifers on BTA7 and QTL9-2 on BTA9, NRR for heifers on BTA7 and BTA23, and NRR for cows on BTA23. Conclusion: The genome wide association study presented here revealed 6 genomic regions associated with FTI. Screening these 6 QTL regions for the underlying female...... quantitative trait locus regions were re-analyzed using a linear mixed model (animal model) for both FTI and its component traits AIS, NRR, IFL and ICF. The underlying traits were analyzed separately for heifers (first parity cows) and cows (later parity cows) for AIS, NRR, and IFL. Results: In the first step...

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

    Science.gov (United States)

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

    2011-05-01

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

  3. Omics Analyses of Trichoderma reesei CBS999.97 and QM6a Indicate the Relevance of Female Fertility to Carbohydrate-Active Enzyme and Transporter Levels.

    Science.gov (United States)

    Tisch, Doris; Pomraning, Kyle R; Collett, James R; Freitag, Michael; Baker, Scott E; Chen, Chia-Ling; Hsu, Paul Wei-Che; Chuang, Yu Chien; Schuster, Andre; Dattenböck, Christoph; Stappler, Eva; Sulyok, Michael; Böhmdorfer, Stefan; Oberlerchner, Josua; Wang, Ting-Fang; Schmoll, Monika

    2017-11-15

    The filamentous fungus Trichoderma reesei is found predominantly in the tropics but also in more temperate regions, such as Europe, and is widely known as a producer of large amounts of plant cell wall-degrading enzymes. We sequenced the genome of the sexually competent isolate CBS999.97, which is phenotypically different from the female sterile strain QM6a but can cross sexually with QM6a. Transcriptome data for growth on cellulose showed that entire carbohydrate-active enzyme (CAZyme) families are consistently differentially regulated between these strains. We evaluated backcrossed strains of both mating types, which acquired female fertility from CBS999.97 but maintained a mostly QM6a genetic background, and we could thereby distinguish between the effects of strain background and female fertility or mating type. We found clear regulatory differences associated with female fertility and female sterility, including regulation of CAZyme and transporter genes. Analysis of carbon source utilization, transcriptomes, and secondary metabolites in these strains revealed that only a few changes in gene regulation are consistently correlated with different mating types. Different strain backgrounds (QM6a versus CBS999.97) resulted in the most significant alterations in the transcriptomes and in carbon source utilization, with decreased growth of CBS999.97 on several amino acids (for example proline or alanine), which further correlated with the downregulation of genes involved in the respective pathways. In combination, our findings support a role of fertility-associated processes in physiology and gene regulation and are of high relevance for the use of sexual crossing in combining the characteristics of two compatible strains or quantitative trait locus (QTL) analysis. IMPORTANCE Trichoderma reesei is a filamentous fungus with a high potential for secretion of plant cell wall-degrading enzymes. We sequenced the genome of the fully fertile field isolate CBS999.97 and

  4. Patterns of Asexuality in China: Sexual Activity, Sexual and Romantic Attraction, and Sexual Desire.

    Science.gov (United States)

    Zheng, Lijun; Su, Yanchen

    2018-05-01

    This study examined patterns of asexuality in Chinese asexual people in terms of sexual activities, sexual/romantic attraction, and sexual desire. The sample included 227 (64 men and 163 women) asexual participants and 57 (26 men and 31 women) uncertain asexual participants recruited from social networks for asexual people. The control group included 217 (115 men and 102 women) heterosexual participants recruited from general social networks. Participants scoring 40 or higher on the Asexuality Identification Scale were classified as asexual. Asexual participants reported having less frequent masturbation, sexual intercourse experience, and sexual and romantic attraction compared to heterosexual participants. Lower sexual attraction among asexuals indicated that "people who experience little or no sexual attraction" would be a more appropriate definition of asexuality. The pattern of uncertain asexual participants' sexual/romantic attraction and sexual desire was intermediate between heterosexual and asexual participants. Asexual participants scored significantly lower on dyadic sexual desire and slightly lower on solitary sexual desire than heterosexual participants. There were significant differences in sexual activities and solitary sexual desire among romantic orientation categories. Homoromantic participants showed higher dyadic sexual desire and were more likely to engage in masturbation, indicating the heterogeneity among asexual people. The findings indicated that Chinese asexual people showed similar patterns of asexuality as in Western nations. Specifically, asexual people have little or no sexual attraction, non-partner-orientated sexual desire, and are heterogeneous in sexual activities and sexual desire. This implies similar mechanisms underlying the etiology of asexuality across cultures.

  5. Asexuality development among middle aged and older men.

    Directory of Open Access Journals (Sweden)

    Yan-Ping Huang

    Full Text Available OBJECTIVES: To assess erectile function in middle-aged and older men with asexuality status and further analyze their specific reasons for this condition. SUBJECTS AND METHODS: Men who had regular sexual intercourse attempts (sex frequency ≥ 1 time per month were classified into mild erectile dysfunction (ED, moderate to severe ED and non-ED according to International Index of Erectile Function-5, and men having no sexual intercourse attempts for at least 6 months were defined as having an asexuality status. The risk factors associated with ED were collected in a sample of 1,531 Chinese men aged 40 to 80 years, and the self-report reasons for asexuality were recorded in asexual cohort individually. Comparative analyses and multivariate regression models were conducted among these groups. RESULTS: The prevalence rates of ED and asexuality status were 49.9% and 37.2%. The asexuality status group had higher risk factors than the moderate to severe ED group in terms of old age (age ≥ 65, adjusted odds ratio (OR 17.69 versus (Vs. 7.19, diabetes (crude OR: 2.40 Vs. 2.36 and hypertension (crude OR: 1.78 Vs. 1.72. The specific reasons for the asexuality status were "erectile difficulty" (52.9%, "do not care about sexuality" (53.5%", "no longer necessary to have sexuality at this age" (47.7%, "severe stress" (44.4%, "severe fatigue" (26.3% and "masturbation" (26.9%. CONCLUSIONS: Men with an asexual status suffer from higher risk factors for ED than men with moderate to severe ED. The majority of this asexual status could be attributed to a full ED, although the reasons for this transient asexuality also involved sexual attitudes and interests, sexual partners and masturbation.

  6. Asexuality development among middle aged and older men.

    Science.gov (United States)

    Huang, Yan-Ping; Chen, Bin; Ping, Ping; Wang, Hong-Xiang; Hu, Kai; Yang, Hao; Zhang, Tao; Feng, Tan; Jin, Yan; Han, Yin-Fa; Wang, Yi-Xin; Huang, Yi-Ran

    2014-01-01

    To assess erectile function in middle-aged and older men with asexuality status and further analyze their specific reasons for this condition. Men who had regular sexual intercourse attempts (sex frequency ≥ 1 time per month) were classified into mild erectile dysfunction (ED), moderate to severe ED and non-ED according to International Index of Erectile Function-5, and men having no sexual intercourse attempts for at least 6 months were defined as having an asexuality status. The risk factors associated with ED were collected in a sample of 1,531 Chinese men aged 40 to 80 years, and the self-report reasons for asexuality were recorded in asexual cohort individually. Comparative analyses and multivariate regression models were conducted among these groups. The prevalence rates of ED and asexuality status were 49.9% and 37.2%. The asexuality status group had higher risk factors than the moderate to severe ED group in terms of old age (age ≥ 65, adjusted odds ratio (OR) 17.69 versus (Vs.) 7.19), diabetes (crude OR: 2.40 Vs. 2.36) and hypertension (crude OR: 1.78 Vs. 1.72). The specific reasons for the asexuality status were "erectile difficulty" (52.9%), "do not care about sexuality" (53.5%)", "no longer necessary to have sexuality at this age" (47.7%), "severe stress" (44.4%), "severe fatigue" (26.3%) and "masturbation" (26.9%). Men with an asexual status suffer from higher risk factors for ED than men with moderate to severe ED. The majority of this asexual status could be attributed to a full ED, although the reasons for this transient asexuality also involved sexual attitudes and interests, sexual partners and masturbation.

  7. Factors associated with the receipt of fertility preservation services along the decision-making pathway in young Canadian female cancer patients.

    Science.gov (United States)

    Yee, Samantha

    2016-02-01

    This study investigated the factors associated with the receipt of fertility preservation (FP) services along the decision-making pathway in young Canadian female cancer patients. The roles of the oncologists were examined. A total of 188 women who were diagnosed with cancer between the ages of 18-39 after the year 2000 and had finished active cancer treatment by the time of the survey (2012-2013) participated in the study. Logistic regression models and Pearson χ (2) tests were used for analyses. The mean ages of participants at diagnosis and at survey time were 30.2 (SD = 3.7) and 33.9 (SD = 5.9). One quarter (n = 45, 23.9 %) did not recall having a fertility discussion with their oncologists. Of the three quarters who had a fertility discussion (n = 143, 76.1 %), discussions were equally initiated by oncologists (n = 71) and patients (n = 72). Of the 49 women (26 %) who consulted a fertility specialist, 17 (9 %) underwent a FP procedure. Fertility concern at diagnosis was the driving force of the receipt of FP services at all decision points. Our findings suggest that not only was the proactive approach of oncologists in initiating a fertility discussion important, the quality of the discussion was equally critical in the decision-making pathway. Oncologists play a pivotal role in the provision of fertility services in that they are not only gate keepers, knowledge brokers, and referral initiators of FP consultation, but also they are catalysts in supporting cancer patients making important FP decision in conjunction with the consultation provided by a fertility specialist.

  8. Profiling the repertoire of phenotypes influenced by environmental cues that occur during asexual reproduction.

    Science.gov (United States)

    Dombrovsky, Aviv; Arthaud, Laury; Ledger, Terence N; Tares, Sophie; Robichon, Alain

    2009-11-01

    The aphid Acyrthosiphon pisum population is composed of different morphs, such as winged and wingless parthenogens, males, and sexual females. The combined effect of reduced photoperiodicity and cold in fall triggers the apparition of sexual morphs. In contrast they reproduce asexually in spring and summer. In our current study, we provide evidence that clonal individuals display phenotypic variability within asexual morph categories. We describe that clones sharing the same morphological features, which arose from the same founder mother, constitute a repertoire of variants with distinct behavioral and physiological traits. Our results suggest that the prevailing environmental conditions influence the recruitment of adaptive phenotypes from a cohort of clonal individuals exhibiting considerable molecular diversity. However, we observed that the variability might be reduced or enhanced by external factors, but is never abolished in accordance with a model of stochastically produced phenotypes. This overall mechanism allows the renewal of colonies from a few adapted individuals that survive drastic episodic changes in a fluctuating environment.

  9. Decision-making in female fertility preservation is balancing the expected burden of fertility preservation treatment and the wish to conceive

    NARCIS (Netherlands)

    Baysal, O.; Bastings, L.; Beerendonk, C.C.M.; Postma, S.A.; Hout, J. in't; Verhaak, C.M.; Braat, D.D.M.; Nelen, W.L.D.M.

    2015-01-01

    STUDY QUESTION: What are the decisive factors in fertility preservation (FP) decision-making in young women scheduled for gonadotoxic therapy? SUMMARY ANSWER: FP decision-making in young women scheduled for gonadotoxic therapy is mainly based on weighing two issues: the intensity of the wish to

  10. The Trojan Female Technique for pest control: a candidate mitochondrial mutation confers low male fertility across diverse nuclear backgrounds in Drosophila melanogaster.

    Science.gov (United States)

    Dowling, Damian K; Tompkins, Daniel M; Gemmell, Neil J

    2015-10-01

    Pest species represent a major ongoing threat to global biodiversity. Effective management approaches are required that regulate pest numbers, while minimizing collateral damage to nontarget species. The Trojan Female Technique (TFT) was recently proposed as a prospective approach to biological pest control. The TFT draws on the evolutionary hypothesis that maternally inherited mitochondrial genomes are prone to the accumulation of male, but not female, harming mutations. These mutations could be harnessed to provide trans-generational fertility-based control of pest species. A candidate TFT mutation was recently described in the fruit fly, Drosophila melanogaster, which confers male-only sterility in the specific isogenic nuclear background in which it is maintained. However, applicability of the TFT relies on mitochondrial mutations whose male-sterilizing effects are general across nuclear genomic contexts. We test this assumption, expressing the candidate TFT-mutation bearing haplotype alongside a range of nuclear backgrounds and comparing its fertility in males, relative to that of control haplotypes. We document consistently lower fertility for males harbouring the TFT mutation, in both competitive and noncompetitive mating contexts, across all nuclear backgrounds screened. This indicates that TFT mutations conferring reduced male fertility can segregate within populations and could be harnessed to facilitate this novel form of pest control.

  11. Genetic parameters for female fertility, locomotion, body condition score, and linear type traits in Czech Holstein cattle

    DEFF Research Database (Denmark)

    Zink, Vojtech; Stipkova, M; Lassen, Jan

    2011-01-01

    The aim of this study was to estimate genetic parameters for fertility traits and linear type traits in the Czech Holstein dairy cattle population. Phenotypic data regarding 12 linear type traits, measured in first lactation, and 3 fertility traits, measured in each of first and second lactation,...

  12. Effect of Pasak Bumi (Eurycoma longifolia Jack) Root In Precopulation Stage to the Fertility of Female Mouse (Mus musculus L.)

    OpenAIRE

    Marlinza, Rosa

    2012-01-01

    Pasak Bumi (Eurycoma longifolia Jack) have potency to be used to increase bodyendurance, to cure malaria drug, and to act as afrodisiak. However, the effect of pasak bumi onwomen fertility, especially at pre-copulation stage was not widely known. This research seeks toreveal the effect pasak bumi extract treated at pre-copulation phase on fertility. This experimentemploy mice (Mus Musculus L.) and was undertaken at Biology and Cemistry laboratories PMIPA, andVeterinary laboratory of Jambi Uni...

  13. An empirical investigation of female labor-force participation, fertility, age at marriage, and wages in Korea.

    Science.gov (United States)

    Lee, B S; Mcelwain, A M

    1985-07-01

    The Korean experience raises questions about the assumption that successful economic development and equitable income distribution are preconditions for rapid fertility declines. During the 1960-70 decade, the total fertility rate in Korea declined by 36% and the crude birth rate fell by 33%, in the absence of significant economic development. This paper uses data from the 1974 Korean Fertility Survey to explore the relationships between the factors responsible for this rapid fertility decline. A simultaneous equation model of fertility, age at marriage, extent of labor force participation during marriage, quality of children, and wages is developed and tested. Rather than to provide definitive measures of these interrelationships, the aim was to investigate the utility of treating several variables as being jointly determined. The results suggest that parental education affects fertility by influencing age at marriage, implying that adult education programs will have little effect on marital fertility. There was some evidence that working women whose jobs are compatible with child care have more children than nonworking women, a finding that should be considered in planning increased job opportunities for women. Urbanized women and those who work before marriage tend to marry later than their less urbanized counterparts or women who do not work prior to marriage. Finally, women who used modern methods of birth control had significantly lower fertility than nonusers of modern methods. There is concern that the Government has reduced budgetary appropriations to family planning since the goal of reducing the annual population growth rate from 3% in 1960 to 2% in 1970 was achieved. It is suggested that family planning expenditures should be deployed to areas such as urban slums that have not yet been reached by family planning programs.

  14. Chromosome length scaling in haploid, asexual reproduction

    International Nuclear Information System (INIS)

    Oliveira, P M C de

    2007-01-01

    We study the genetic behaviour of a population formed by haploid individuals which reproduce asexually. The genetic information for each individual is stored along a bit-string (or chromosome) with L bits, where 0-bits represent the wild allele and 1-bits correspond to harmful mutations. Each newborn inherits this chromosome from its parent with a few random mutations: on average a fixed number m of bits are flipped. Selection is implemented according to the number N of 1-bits counted along the individual's chromosome: the smaller N the higher the probability an individual has to survive a new time step. Such a population evolves, with births and deaths, and its genetic distribution becomes stabilized after sufficiently many generations have passed. The question we pose concerns the procedure of increasing L. The aim is to get the same distribution of genetic loads N/L among the equilibrated population, in spite of a larger L. Should we keep the same mutation rate m/L for different values of L? The answer is yes, which intuitively seems to be plausible. However, this conclusion is not trivial, according to our simulation results: the question also involves the population size

  15. A Unique Egg Cortical Granule Localization Motif Is Required for Ovastacin Sequestration to Prevent Premature ZP2 Cleavage and Ensure Female Fertility in Mice.

    Directory of Open Access Journals (Sweden)

    Bo Xiong

    2017-01-01

    Full Text Available Monospermic fertilization is mediated by the extracellular zona pellucida composed of ZP1, ZP2 and ZP3. Sperm bind to the N-terminus of ZP2 which is cleaved after fertilization by ovastacin (encoded by Astl exocytosed from egg cortical granules to prevent sperm binding. AstlNull mice lack the post-fertilization block to sperm binding and the ability to rescue this phenotype with AstlmCherry transgenic mice confirms the role of ovastacin in providing a definitive block to polyspermy. During oogenesis, endogenous ovastacin traffics through the endomembrane system prior to storage in peripherally located cortical granules. Deletion mutants of ovastacinmCherry expressed in growing oocytes define a unique 7 amino acid motif near its N-terminus that is necessary and sufficient for cortical granule localization. Deletion of the 7 amino acids by CRISPR/Cas9 at the endogenous locus (AstlΔ prevents cortical granule localization of ovastacin. The misdirected enzyme is present within the endomembrane system and ZP2 is prematurely cleaved. Sperm bind poorly to the zona pellucida of AstlΔ/Δ mice with partially cleaved ZP2 and female mice are sub-fertile.

  16. Improvement in genetic evaluation of female fertility in dairy cattle using multiple-trait models including milk production traits

    DEFF Research Database (Denmark)

    Sun, C; Madsen, P; Lund, M S

    2010-01-01

    This study investigated the improvement in genetic evaluation of fertility traits by using production traits as secondary traits (MILK = 305-d milk yield, FAT = 305-d fat yield, and PROT = 305-d protein yield). Data including 471,742 records from first lactations of Denmark Holstein cows, covering...... the years of inseminations during first lactations from 1995 to 2004, were analyzed. Six fertility traits (i.e., interval in days from calving to first insemination, calving interval, days open, interval in days from first to last insemination, numbers of inseminations per conception, and nonreturn rate...... stability and predictive ability than single-trait models for all the fertility traits, except for nonreturn rate within 56 d after first service. The stability and predictive ability for the model including MILK or PROT were similar to the model including all 3 milk production traits and better than...

  17. Effects of enoxaparin and unfractionated heparin in prophylactic and therapeutic doses on the fertility of female Wistar rats.

    Science.gov (United States)

    Figueiró-Filho, Ernesto Antonio; Aydos, Ricardo Dutra; Senefonte, Flávio Renato de Almeida; Ferreira, Cristiane Munaretto; Pereira, Erica Freire de Vasconcelos; Oliveira, Vanessa Marcon de; Menezes, Giovanna Pádoa de; Bósio, Marco Antonio Costa

    2014-07-01

    To evaluate the effects of exposure of enoxaparin and unfractionated heparin (UFH) in prophylactic and therapeutic doses on the fertility rates of pregnant healthy Wistar rats. Enoxaparin and UFH were administered in prophylactic doses 1 mg/Kg/day 72 UI/Kg/day, and in therapeutic doses at 2 mg/kg/day 400UI/Kg/day. The rats were divided into five groups. The number of live and dead foetuses was quantified. The uterine horns were dissected and the presence of early and late reabsorptions (abortions) was determined. A peffect on fertility with the use of anticoagulant drugs in pregnant healthy Wistar rats.

  18. Decision-making in female fertility preservation is balancing the expected burden of fertility preservation treatment and the wish to conceive.

    Science.gov (United States)

    Baysal, Ö; Bastings, L; Beerendonk, C C M; Postma, S A E; IntHout, J; Verhaak, C M; Braat, D D M; Nelen, W L D M

    2015-07-01

    What are the decisive factors in fertility preservation (FP) decision-making in young women scheduled for gonadotoxic therapy? FP decision-making in young women scheduled for gonadotoxic therapy is mainly based on weighing two issues: the intensity of the wish to conceive a child in the future and the expected burden of undergoing FP treatment. Future fertility is of importance for young cancer patients whose reproductive function is being threatened by oncological therapy. To prevent or reduce severe psychological effects of infertility as well as feelings of regret about their FP decision after cancer treatment, the quality of fertility preservation counselling (FPC) should be improved. To improve care, those issues forming a decisive factor in FP decision-making for patients should be clarified, as these issues deserve extensive discussion during FPC. Until now, decisive factors have not been isolated from the complex interplay of all aspects of FP that women contemplate during FP decision-making. By using a mixed methods methodology, a questionnaire developed after qualitative research involving a selected group of five women who previously received FPC was retrospectively sent to eligible patients (n = 143) who had received FPC (1999 - July 2013) and to whom at least one FP option was offered. Patients had received FPC at a university hospital in the Netherlands, in a setting where financial factors do not play a role in FP. They were aged ≥16 years and were scheduled for gonadotoxic treatment. The relationship between patients' baseline characteristics, their attributed importance to 28 relevant importance items and their FP choices was investigated. After five interviews, 28 importance items for FP decision-making were identified and included in our questionnaire. Of these 28 importance items, 24 items could be clustered into seven importance themes. A total of 87 patients (61%) responded to our questionnaire. After performing a multivariable logistic

  19. A unique mating strategy without physical contact during fertilization in Bombay Night Frogs (Nyctibatrachus humayuni) with the description of a new form of amplexus and female call.

    Science.gov (United States)

    Willaert, Bert; Suyesh, Robin; Garg, Sonali; Giri, Varad B; Bee, Mark A; Biju, S D

    2016-01-01

    Anurans show the highest diversity in reproductive modes of all vertebrate taxa, with a variety of associated breeding behaviours. One striking feature of anuran reproduction is amplexus. During this process, in which the male clasps the female, both individuals' cloacae are juxtaposed to ensure successful external fertilization. Several types of amplexus have evolved with the diversification of anurans, and secondary loss of amplexus has been reported in a few distantly related taxa. Within Nyctibatrachus, a genus endemic to the Western Ghats of India, normal axillary amplexus, a complete loss of amplexus, and intermediate forms of amplexus have all been suggested to occur, but many species remain unstudied. Here, we describe the reproductive behaviour of N. humayuni, including a new type of amplexus. The dorsal straddle, here defined as a loose form of contact in which the male sits on the dorsum of the female prior to oviposition but without clasping her, is previously unreported for anurans. When compared to known amplexus types, it most closely resembles the form of amplexus observed in Mantellinae. Furthermore, we prove that, opposed to the situation in most anurans, male semen release happens before egg deposition. We hypothesize that the male ejaculates on the female's dorsum and that sperm subsequently runs from her back and hind legs before fertilizing the eggs. A second feature characterizing anuran breeding is the advertisement call, mostly produced solely by males. Despite recent descriptions of several new Nyctibatrachus species, few studies have explored their vocal repertoire. We describe both the male advertisement call and a female call for N. humayuni. The presence of a female call has not been reported within Nyctibatrachidae, and has been reported in less than 0.5% of anuran species. Altogether, our results highlight a striking diversity and several unique aspects of Nyctibatrachus breeding behaviour.

  20. Genetic parameters for female fertility, locomotion, body condition score, and linear type traits in Czech Holstein cattle.

    Science.gov (United States)

    Zink, V; Štípková, M; Lassen, J

    2011-10-01

    The aim of this study was to estimate genetic parameters for fertility traits and linear type traits in the Czech Holstein dairy cattle population. Phenotypic data regarding 12 linear type traits, measured in first lactation, and 3 fertility traits, measured in each of first and second lactation, were collected from 2005 to 2009 in the progeny testing program of the Czech-Moravian Breeders Corporation. The number of animals for each linear type trait was 59,467, except for locomotion, where 53,436 animals were recorded. The 3-generation pedigree file included 164,125 animals. (Co)variance components were estimated using AI-REML in a series of bivariate analyses, which were implemented via the DMU package. Fertility traits included days from calving to first service (CF1), days open (DO1), and days from first to last service (FL1) in first lactation, and days from calving to first service (CF2), days open (DO2), and days from first to last service (FL2) in second lactation. The number of animals with fertility data varied between traits and ranged from 18,915 to 58,686. All heritability estimates for reproduction traits were low, ranging from 0.02 to 0.04. Heritability estimates for linear type traits ranged from 0.03 for locomotion to 0.39 for stature. Estimated genetic correlations between fertility traits and linear type traits were generally neutral or positive, whereas genetic correlations between body condition score and CF1, DO1, FL1, CF2 and DO2 were mostly negative, with the greatest correlation between BCS and CF2 (-0.51). Genetic correlations with locomotion were greatest for CF1 and CF2 (-0.34 for both). Results of this study show that cows that are genetically extreme for angularity, stature, and body depth tend to perform poorly for fertility traits. At the same time, cows that are genetically predisposed for low body condition score or high locomotion score are generally inferior in fertility. Copyright © 2011 American Dairy Science Association

  1. Biological markers of asexuality: Handedness, birth order, and finger length ratios in self-identified asexual men and women.

    Science.gov (United States)

    Yule, Morag A; Brotto, Lori A; Gorzalka, Boris B

    2014-02-01

    Human asexuality is defined as a lack of sexual attraction to anyone or anything and it has been suggested that it may be best conceptualized as a sexual orientation. Non-right-handedness, fraternal birth order, and finger length ratio (2D:4D) are early neurodevelopmental markers associated with sexual orientation. We conducted an Internet study investigating the relationship between self-identification as asexual, handedness, number of older siblings, and self-measured finger-lengths in comparison to individuals of other sexual orientation groups. A total of 325 asexuals (60 men and 265 women; M age, 24.8 years), 690 heterosexuals (190 men and 500 women; M age, 23.5 years), and 268 non-heterosexuals (homosexual and bisexual; 64 men and 204 women; M age, 29.0 years) completed online questionnaires. Asexual men and women were 2.4 and 2.5 times, respectively, more likely to be non-right-handed than their heterosexual counterparts and there were significant differences between sexual orientation groups in number of older brothers and older sisters, and this depended on handedness. Asexual and non-heterosexual men were more likely to be later-born than heterosexual men, and asexual women were more likely to be earlier-born than non-heterosexual women. We found no significant differences between sexual orientation groups on measurements of 2D:4D ratio. This is one of the first studies to test and provide preliminary empirical support for an underlying neurodevelopmental basis to account for the lack of sexual attraction characteristic of asexuality.

  2. [Female age - related fertility decline: Far from the myth of the "selfish working-girl" and the "right to have a child"].

    Science.gov (United States)

    Vialle, M; Perrin, J; Amar-Hoffet, A; Boyer, P; Courbiere, B

    2016-04-01

    To study the social dimension of age-related female infertility through an analysis of three key themes: the personal life histories of infertile women over 40 years of age; representations of age and the desire to become pregnant after age 40; opinions of French legislations framing Assisted Reproductive Technologies, age limits, egg donation, and egg freezing for non-medical reasons. This qualitative sociological study was based on semi-structured interviews with infertile women over age 40 going through fertility treatments. The interviews contained three parts: personal and relationship histories; experiences related to age; opinions related to French legislation. Twenty-three interviews were conducted; each lasting between 90 to 120minutes. Far from having similar life histories, the women interviewed had very different backgrounds leading to their desire for a pregnancy after 40 years of age. From the beginning of their fertility treatments, they perceived a "race against the clock". This feeling of urgency accompanied their experiences and was related to the desire to not be too old for their future child. The women interviewed were mainly in favor of loosening French bioethical laws in order to avoid the need to travel abroad to pursue fertility treatments. The profiles studied attest to a growing gap between biological and biographical temporalities, as well as an inability of women to reduce their desire for a child. Faced with this disparity, egg donation and egg freezing were seen as practical solutions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  3. High-dose radioiodine treatment for differentiated thyroid carcinoma is not associated with change in female fertility or any genetic risk to the offspring

    International Nuclear Information System (INIS)

    Bal, Chandrasekhar; Kumar, Ajay; Tripathi, Madhavi; Chandrashekar, Narayana; Phom, Hentok; Murali, Nadig R.; Chandra, Prem; Pant, Gauri S.

    2005-01-01

    Background: We tried to evaluate the female fertility and genetic risk to the offspring from the exposure to high-dose 131 I by assessing the pregnancy outcomes and health status of the children of female patients with differentiated thyroid cancer who had received therapeutic doses of 131 I. Materials and Methods: From 1967 to 2002, a total of 1,282 women had been treated with 131 I. Of these patients, 692 (54%) were in the reproductive age group (18-45 years). Forty women had a total of 50 pregnancies after high-dose 131 I. Age at presentation ranged from 16 to 36 years (mean, 23 ± 4 years). Histopathology was papillary thyroid cancer in 32 cases and follicular thyroid cancer in 8 cases. Results: Single high-dose therapy was given in 30 cases, 2 doses were given in 7 cases, 3 doses were given in 2 cases, and four doses were given in 1 case in which lung metastases had occurred. In 37 patients (92%), disease was successfully ablated before pregnancy. Ovarian absorbed-radiation dose calculated by the MIRD method ranged from 3.5 to 60 cGy (mean, 12 ± 11 cGy). The interval between 131 I therapy and pregnancy varied from 7 to 120 months (37.4 ± 28.2 months). Three spontaneous abortions occurred in 2 women. Forty-seven babies (20 females and 27 males) were born. Forty-four babies were healthy with normal birth weight and normal developmental milestones. Twenty women delivered their first baby after 131 I therapy. The youngest child in our series is 11 months of age, and the oldest is 8.5 years of age. Conclusions: Female fertility is not affected by high-dose radioiodine treatment, and the therapy does not appear to be associated with any genetic risks to the offspring

  4. The Drosophila Su(var)3-7 gene is required for oogenesis and female fertility, genetically interacts with piwi and aubergine, but impacts only weakly transposon silencing.

    Science.gov (United States)

    Basquin, Denis; Spierer, Anne; Begeot, Flora; Koryakov, Dmitry E; Todeschini, Anne-Laure; Ronsseray, Stéphane; Vieira, Cristina; Spierer, Pierre; Delattre, Marion

    2014-01-01

    Heterochromatin is made of repetitive sequences, mainly transposable elements (TEs), the regulation of which is critical for genome stability. We have analyzed the role of the heterochromatin-associated Su(var)3-7 protein in Drosophila ovaries. We present evidences that Su(var)3-7 is required for correct oogenesis and female fertility. It accumulates in heterochromatic domains of ovarian germline and somatic cells nuclei, where it co-localizes with HP1. Homozygous mutant females display ovaries with frequent degenerating egg-chambers. Absence of Su(var)3-7 in embryos leads to defects in meiosis and first mitotic divisions due to chromatin fragmentation or chromosome loss, showing that Su(var)3-7 is required for genome integrity. Females homozygous for Su(var)3-7 mutations strongly impair repression of P-transposable element induced gonadal dysgenesis but have minor effects on other TEs. Su(var)3-7 mutations reduce piRNA cluster transcription and slightly impact ovarian piRNA production. However, this modest piRNA reduction does not correlate with transposon de-silencing, suggesting that the moderate effect of Su(var)3-7 on some TE repression is not linked to piRNA production. Strikingly, Su(var)3-7 genetically interacts with the piwi and aubergine genes, key components of the piRNA pathway, by strongly impacting female fertility without impairing transposon silencing. These results lead us to propose that the interaction between Su(var)3-7 and piwi or aubergine controls important developmental processes independently of transposon silencing.

  5. The Drosophila Su(var)3–7 Gene Is Required for Oogenesis and Female Fertility, Genetically Interacts with piwi and aubergine, but Impacts Only Weakly Transposon Silencing

    Science.gov (United States)

    Begeot, Flora; Koryakov, Dmitry E.; Todeschini, Anne-Laure; Ronsseray, Stéphane; Vieira, Cristina; Spierer, Pierre; Delattre, Marion

    2014-01-01

    Heterochromatin is made of repetitive sequences, mainly transposable elements (TEs), the regulation of which is critical for genome stability. We have analyzed the role of the heterochromatin-associated Su(var)3–7 protein in Drosophila ovaries. We present evidences that Su(var)3–7 is required for correct oogenesis and female fertility. It accumulates in heterochromatic domains of ovarian germline and somatic cells nuclei, where it co-localizes with HP1. Homozygous mutant females display ovaries with frequent degenerating egg-chambers. Absence of Su(var)3–7 in embryos leads to defects in meiosis and first mitotic divisions due to chromatin fragmentation or chromosome loss, showing that Su(var)3–7 is required for genome integrity. Females homozygous for Su(var)3–7 mutations strongly impair repression of P-transposable element induced gonadal dysgenesis but have minor effects on other TEs. Su(var)3–7 mutations reduce piRNA cluster transcription and slightly impact ovarian piRNA production. However, this modest piRNA reduction does not correlate with transposon de-silencing, suggesting that the moderate effect of Su(var)3–7 on some TE repression is not linked to piRNA production. Strikingly, Su(var)3–7 genetically interacts with the piwi and aubergine genes, key components of the piRNA pathway, by strongly impacting female fertility without impairing transposon silencing. These results lead us to propose that the interaction between Su(var)3–7 and piwi or aubergine controls important developmental processes independently of transposon silencing. PMID:24820312

  6. The evolution of polyandry: patterns of genotypic variation in female mating frequency, male fertilization success and a test of the sexy-sperm hypothesis.

    Science.gov (United States)

    Simmons, L W

    2003-07-01

    The sexy-sperm hypothesis predicts that females obtain indirect benefits for their offspring via polyandy, in the form of increased fertilization success for their sons. I use a quantitative genetic approach to test the sexy-sperm hypothesis using the field cricket Teleogryllus oceanicus. Previous studies of this species have shown considerable phenotypic variation in fertilization success when two or more males compete. There were high broad-sense heritabilities for both paternity and polyandry. Patterns of genotypic variance were consistent with X-linked inheritance and/or maternal effects on these traits. The genetic architecture therefore precludes the evolution of polyandry via a sexy-sperm process. Thus the positive genetic correlation between paternity in sons and polyandry in daughters predicted by the sexy-sperm hypothesis was absent. There was significant heritable variation in the investment by females in ovaries and by males in the accessory gland. Surprisingly there was a very strong genetic correlation between these two traits. The significance of this genetic correlation for the coevolution of male seminal products and polyandry is discussed.

  7. Understanding asexual identity as a means to facilitate culturally competent care: A systematic literature review.

    Science.gov (United States)

    Jones, Catriona; Hayter, Mark; Jomeen, Julie

    2017-12-01

    To provide a contemporary overview of asexuality and the implications this has for healthcare practice. Individuals belonging to sexual minority groups face many barriers in accessing appropriate health care. The term "sexual minority group" is usually used to refer to lesbian women, gay, bisexual and transgender individuals. Anecdotal and research evidence suggests that those who identify as asexual have similar poor experiences. Systematic review and qualitative analysis. This work uses a systematic review and qualitative analysis of the existing interview data from self-identified asexuals, to construct features of the asexual identity. The findings will help practitioners and health professionals develop an understanding of this poorly understood construct. Ultimately this work is aimed at facilitating culturally competent care in the context of asexuality. Qualitative analysis produced three themes, which can be used, not only to frame asexuality in a positive and normalising way, but also to provide greater understanding of asexuality, "romantic differences coupled with sexual indifference," "validation through engagement with asexual communities" and "a diversity of subasexual identities." Having some understanding of what it means to identify as asexual, and respecting the choices made by asexuals can markedly improve the experiences of those who embrace an asexual identity when engaging with health care. Anecdotal evidence, taken from one of the largest asexual online forums, suggests that a number of self-identified asexuals choose not to disclose their identity to healthcare professionals through fear of their asexual status being pathologised, problematised or judged. Given that asexuality is a poorly understood concept, this may be due to lack of understanding on behalf of healthcare providers. The review provides health professionals and practitioners working in clinical settings with some insights of the features of an asexual identity to facilitate

  8. Female fertility following dose-adjusted EPOCH-R chemotherapy in primary mediastinal B-cell lymphomas.

    Science.gov (United States)

    Gharwan, Helen; Lai, Catherine; Grant, Cliona; Dunleavy, Kieron; Steinberg, Seth M; Shovlin, Margaret; Fojo, Tito; Wilson, Wyndham H

    2016-07-01

    We assessed fertility/gonadal function in premenopausal women treated with dose-adjusted EPOCH-Rituximab for untreated primary mediastinal B-cell lymphoma (PMBL). Eligible patents were ≤ 50 years and premenopausal. Serial reproductive histories were obtained and hormonal assays were performed on serum samples before, at the end of treatment and 4-18 months later. Twenty-eight eligible women had a median age (range) of 31 (21-50) years and were followed a median of 7.3 years. Of 23 patients who completed a questionnaire, 19 (83%) were and four were not menstruating prior to chemotherapy. Amenorrhea developed in 12 patients during chemotherapy. At > 1-year follow-up, 14/19 (74%) patients were menstruating, all years old, and six (43%) of these patients delivered healthy children. Hormonal assays showed ovarian dysfunction during chemotherapy in all patients with varying recovery at 4-18 months after treatment. Fertility was preserved in most women with ovarian failure confined to patients > 40 years old.

  9. Evolution of complex asexual reproductive strategies in jellyfish

    DEFF Research Database (Denmark)

    Schnedler-Meyer, Nicolas Azaña; Pigolotti, Simone; Mariani, Patrizio

    2018-01-01

    Many living organisms in terrestrial and aquatic ecosystems rely on multiple reproductive strategies to reduce the risk of extinction in variable environments. Examples are provided by the polyp stage of several bloom-forming jellyfish species, which can reproduce asexually using different buddin...

  10. Paradoxical Impact of Ileal Pouch-Anal Anastomosis on Male and Female Fertility in Patients With Ulcerative Colitis.

    Science.gov (United States)

    Pachler, Frederik R; Brandsborg, Søren B; Laurberg, Søren

    2017-06-01

    Birth rates in males with ulcerative colitis and ileal pouch-anal anastomosis have not been studied. This study aimed to estimate birth rates in males and females with ulcerative colitis and study the impact of ileal pouch-anal anastomosis. This was a retrospective registry-based cohort study that was performed over a 30-year period. Records for parenting a child from the same period were cross-linked with patient records, and birth rates were calculated using 15 through 49 years as age limits. All data were prospectively registered. All patients with ulcerative colitis and ulcerative colitis with ileal pouch-anal anastomosis between 1980 and 2010 were identified in Danish national databases. The primary outcomes measured were birth rates in females and males with ulcerative colitis and ulcerative colitis with ileal pouch-anal anastomosis. We included 27,379 patients with ulcerative colitis (12,812 males and 14,567 females); 1544 had ileal pouch-anal anastomosis (792 males and 752 females). Patients with ulcerative colitis have slightly reduced birth rates (males at 40.8 children/1000 years, background population 43.2, females at 46.2 children/1000 years, background population 49.1). After ileal pouch-anal anastomosis, males had increased birth rates at 47.8 children/1000 years in comparison with males with ulcerative colitis without ileal pouch-anal anastomosis (40.5 children/1000 years), whereas females had reduced birth rates at 27.6 children/1000 years in comparison with females with ulcerative colitis without ileal pouch-anal anastomosis (46.8 children/1000 years). Only birth rates were investigated and not fecundability. Furthermore, there is a question about misattributed paternity, but this has previously been shown to be less than 5%. Ulcerative colitis per se has little impact on birth rates in both sexes, but ileal pouch-anal anastomosis surgery leads to a reduction in birth rates in females and an increase in birth rates in males. This has clinical

  11. Process of egg formation in the female body cavity and fertilization in male eggs of Phytoseiulus persimilis (Acari: Phytoseiidae).

    Science.gov (United States)

    Toyoshima, S; Nakamura, M; Nagahama, Y; Amano, H

    2000-01-01

    The process of egg formation in the body cavity of a phytoseiid mite, Phytoseiulus persimilis, was observed to examine fertilization of male eggs. After insemination, one of the ova at the periphery of the ovary began to expand, taking up yolk. Two pronuclei appeared in the expanded egg, located dorsally in the ovary, and yolk granules were formed gradually. After the egg became filled with yolk granules the two pronuclei fused. The egg moved via the narrow entrance at the ventral region into the oviduct, where the eggshell was formed. When the eggshell was complete, and while embryogenesis proceeded, the egg was deposited. In the meantime some ova began to expand sequentially and two joining pronuclei appeared in expanding eggs. The joining pronuclei in the first egg proved male diploidy. This is additional evidence of pseudo-arrhenotoky in this phytoseiid mite species, since the first eggs developed into males.

  12. EFFECTS OF SILVER NANOPARTICLES IN SOLUTION AND LIPOSOMAL FORM ON SOME BLOOD PARAMETERS IN FEMALE RABBITS DURING FERTILIZATION AND EARLY EMBRYONIC DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Vasyl Syrvatka

    2014-02-01

    Full Text Available Silver nanoparticles are the most rapidly growing classes of nanoproducts. In this study, we investigated the influence of subcutaneous injections of silver nanoparticles in solution and in liposomal form on hematological and biochemical parameters of blood of New Zealand White rabbits during hormonal treatment, fertilization and early embryonic development. The females treated by free silver nanoparticles and silver nanoparticles in liposomal form received silver at a dose of 10 µg/kg/day in 5 % glucose solution during 28 days. Blood sampling was done four times: the day before the compounds administration; on day 7 after the compounds administration; in the period after hormonal induction and fertilization and on the 14th day of pregnancy. Our results showed changes in some biochemical (lactate dehydrogenase activities, progesterone and estradiol concentration, malondialdehyde level, etc. and hematological (hematocrit, mean cell volume, mean corpuscular hemoglobin concentration, etc. parameters under the influence of hormonal treatment and pregnancy. The concentration of progesterone showed significantly higher values (P˂0.05 on GDs 1 in S group than in C group. The percentage of neutrophils was significantly higher in SG rabbits after 7 days of silver nanoparticles administration than that in the CG. There were no significant changes in red blood cells parameters, platelets, and activity of some ferments (ALP, AST, ALT, LDH, GGT between control and silver groups during the entire period of experiment. In conclusion, the hematological and biochemical values of blood obtained in the given study showed that free silver nanoparticles and silver nanoparticles in liposomal form in the investigated concentrations had no toxic effect on hormonal treatment, fertilization and early embryonic development in New Zealand White rabbits.

  13. Long term effects of prenatal X ray on human females: early fertility and frequency of operations to prevent pregnancy

    International Nuclear Information System (INIS)

    Meyer, M.B.; Tonascia, J.A.

    1980-01-01

    The subject of this paper is a long-term epidemiological study of human females who were exposed to radiation from maternal diagnostic x-ray procedures when they were in utero, compared with matched, unexposed controls. The study was designed to investigate possible effects of in-utero exposure, with particular interest being paid to reproductive capacity. In the human female and other mammals, because all mitotic divisions of germ cells occur during fetal life, the female baby is born with a finite supply of oocytes and future eggs. This supply is continuously depleted throughout life by ovulation and by cell degeneration, and there is no way for damaged or lost cells to be replaced. Experimental studies in a number of species have shown that female germ cells are extremely sensitive to radiation damage at two times during development. In humans the first of these probably occurs at around 4 to 5 months of gestation, and the second probably occurs around the time of birth. Radiation damage at these sensitive stages might show up at puberty ad during reproductive life, and might be detected by a well-designed study

  14. The strength of direct selection against female promiscuity is associated with rates of extrapair fertilizations in socially monogamous songbirds

    Czech Academy of Sciences Publication Activity Database

    Albrecht, Tomáš; Kreisinger, J.; Piálek, Jaroslav

    2006-01-01

    Roč. 167, č. 5 (2006), s. 739-744 ISSN 0003-0147 Institutional research plan: CEZ:AV0Z60930519 Keywords : comparative analysis * female infidelity * passerines Subject RIV: EG - Zoology Impact factor: 4.660, year: 2006

  15. Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011–12

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2017-01-01

    Full Text Available Background: District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Objective: Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Material and Methods: Data from Annual Health Survey (2011-12 was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Results: Female married illiteracy positively associated with total fertility rate and explained more than half (53% of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR = 2.7. The next left side branch was again married illiteracy with splits at 23% to determine TFR = 2.1. Conclusion: We conclude that female married illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run.

  16. Oocyte cryopreservation for fertility preservation in postpubertal female children at risk for premature ovarian failure due to accelerated follicle loss in Turner syndrome or cancer treatments.

    Science.gov (United States)

    Oktay, K; Bedoschi, G

    2014-12-01

    To preliminarily study the feasibility of oocyte cryopreservation in postpubertal girls aged between 13 and 15 years who were at risk for premature ovarian failure due to the accelerated follicle loss associated with Turner syndrome or cancer treatments. Retrospective cohort and review of literature. Academic fertility preservation unit. Three girls diagnosed with Turner syndrome, 1 girl diagnosed with germ-cell tumor. and 1 girl diagnosed with lymphoblastic leukemia. Assessment of ovarian reserve, ovarian stimulation, oocyte retrieval, in vitro maturation, and mature oocyte cryopreservation. Response to ovarian stimulation, number of mature oocytes cryopreserved and complications, if any. Mean anti-müllerian hormone, baseline follical stimulating hormone, estradiol, and antral follicle counts were 1.30 ± 0.39, 6.08 ± 2.63, 41.39 ± 24.68, 8.0 ± 3.2; respectively. In Turner girls the ovarian reserve assessment indicated already diminished ovarian reserve. Ovarian stimulation and oocyte cryopreservation was successfully performed in all female children referred for fertility preservation. A range of 4-11 mature oocytes (mean 8.1 ± 3.4) was cryopreserved without any complications. All girls tolerated the procedure well. Oocyte cryopreservation is a feasible technique in selected female children at risk for premature ovarian failure. Further studies would be beneficial to test the success of oocyte cryopreservation in young girls. Copyright © 2014 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  17. Asexuality: Sexual Orientation, Paraphilia, Sexual Dysfunction, or None of the Above?

    Science.gov (United States)

    Brotto, Lori A; Yule, Morag

    2017-04-01

    Although lack of sexual attraction was first quantified by Kinsey, large-scale and systematic research on the prevalence and correlates of asexuality has only emerged over the past decade. Several theories have been posited to account for the nature of asexuality. The goal of this review was to consider the evidence for whether asexuality is best classified as a psychiatric syndrome (or a symptom of one), a sexual dysfunction, or a paraphilia. Based on the available science, we believe there is not sufficient evidence to support the categorization of asexuality as a psychiatric condition (or symptom of one) or as a disorder of sexual desire. There is some evidence that a subset of self-identified asexuals have a paraphilia. We also considered evidence supporting the classification of asexuality as a unique sexual orientation. We conclude that asexuality is a heterogeneous entity that likely meets conditions for a sexual orientation, and that researchers should further explore evidence for such a categorization.

  18. Chromosome Synapsis and Recombination in Male-Sterile and Female-Fertile Interspecies Hybrids of the Dwarf Hamsters (Phodopus, Cricetidae

    Directory of Open Access Journals (Sweden)

    Tatiana I. Bikchurina

    2018-04-01

    Full Text Available Hybrid sterility is an important step in the speciation process. Hybrids between dwarf hamsters Phodopus sungorus and P. campbelli provide a good model for studies in cytological and genetic mechanisms of hybrid sterility. Previous studies in hybrids detected multiple abnormalities of spermatogenesis and a high frequency of dissociation between the X and Y chromosomes at the meiotic prophase. In this study, we found that the autosomes of the hybrid males and females underwent paring and recombination as normally as their parental forms did. The male hybrids showed a significantly higher frequency of asynapsis and recombination failure between the heterochromatic arms of the X and Y chromosomes than the males of the parental species. Female hybrids as well as the females of the parental species demonstrated a high incidence of centromere misalignment at the XX bivalent and partial asynapsis of the ends of its heterochromatic arms. In all three karyotypes, recombination was completely suppressed in the heterochromatic arm of the X chromosome, where the pseudoautosomal region is located. We propose that this recombination pattern speeds up divergence of the X- and Y-linked pseudoautosomal regions between the parental species and results in their incompatibility in the male hybrids.

  19. Modulation of Steroidogenic Pathway in Rat Granulosa Cells with Subclinical Cd Exposure and Insulin Resistance: An Impact on Female Fertility

    Directory of Open Access Journals (Sweden)

    Muskaan Belani

    2014-01-01

    Full Text Available Changes in lifestyle lead to insulin resistance (IR in females ultimately predisposing them towards infertility. In addition, cadmium (Cd, an environmental endocrine disruptor, is reported for detrimental effects on granulosa cells, thus leading to ovarian dysfunction. A combination of these factors, lifestyle and environment, seems to play a role in etiology of idiopathic infertility that accounts for 50% amongst the total infertility cases. To address this issue, we made an attempt to investigate the extent of Cd impact on insulin-resistant (IR granulosa cells. We exposed adult female Charles Foster rats to dexamethasone and confirmed IR condition by fasting insulin resistance index (FIRI. On treatment of IR rats with Cd, the preliminary studies demonstrated prolonged estrous cyclicity, decrease in serum estradiol concentrations, abnormal histology of ovary, and increased granulosa cell death. Further gene and protein expression studies of steroidogenic acute regulatory (StAR protein, 17β-hydroxysteroid dehydrogenase (17β-HSD, and cytochrome P450 aromatase (CYP19A1 were performed. Protein expression studies demonstrated significant decrease in treated groups when compared with control. Study revealed that, in spite of the molecular parameters being affected at varied level, overall ovarian physiology is maximally affected in IR and Cd coexposed group, thus mimicking the condition similar to those prevailing in infertile females.

  20. Polycystic ovary syndrome and endometrial hyperplasia: an overview of the role of bariatric surgery in female fertility.

    Science.gov (United States)

    Charalampakis, Vasileios; Tahrani, Abd A; Helmy, Ahmed; Gupta, Janesh K; Singhal, Rishi

    2016-12-01

    One of the most effective methods to tackle obesity and its related comorbidities is bariatric surgery. Polycystic ovary syndrome (PCOS) and endometrial hyperplasia (EH), which are associated with increased risk of endometrial carcinoma, have been identified as potentially new indications for bariatric surgery. PCOS is the most common endocrine disorder in women in the reproductive age and is associated with several components of the metabolic syndrome such as obesity, insulin resistance and hypertension. EH is a pre-cancerous condition which arises in the presence of chronic exposure to estrogen unopposed by progesterone such as both in PCOS and obesity. The main bariatric procedures are Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy and laparoscopic adjustable gastric banding. These procedures are well established and when correctly selected and performed by experienced bariatric surgeons, they can achieve significant weight loss and remission of obesity related co-morbidities. Studies have shown that bariatric surgery can play an important role in the management of patients with PCOS and improve fertility. Similarly, bariatric surgery has a positive effect on endometrial hyperplasia, making surgically induced weight loss a potentially attractive option for endometrial cancer prevention and treatment. Obesity has an adverse impact on spontaneous pregnancy, assisted reproduction methods and feto-maternal outcomes. After bariatric surgery obese women with subfertility can achieve spontaneous pregnancy. However, while bariatric surgery reduces the risk of pre-eclampsia and gestational diabetes, there is an increased risk of small for gestational age and possible increased risk of stillborn or neonatal death. In this article we will review the evidence regarding the use of bariatric surgery as a treatment modality in patients with PCOS and EH. We also provide an overview of the common bariatric procedures. Copyright © 2016 Elsevier Ireland Ltd. All rights

  1. Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011-12.

    Science.gov (United States)

    Kumar, Rajesh; Dogra, Vishal; Rani, Khushbu; Sahu, Kanti

    2017-01-01

    District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Data from Annual Health Survey (2011-12) was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Female married illiteracy positively associated with total fertility rate and explained more than half (53%) of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR illiteracy with splits at 23% to determine TFR illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run.

  2. Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011–12

    Science.gov (United States)

    Kumar, Rajesh; Dogra, Vishal; Rani, Khushbu; Sahu, Kanti

    2017-01-01

    Background: District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Objective: Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Material and Methods: Data from Annual Health Survey (2011-12) was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Results: Female married illiteracy positively associated with total fertility rate and explained more than half (53%) of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR illiteracy with splits at 23% to determine TFR illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run. PMID:29416999

  3. Gonad establishment during asexual reproduction in the annelid Pristina leidyi.

    Science.gov (United States)

    Özpolat, B Duygu; Bely, Alexandra E

    2015-09-01

    Animals that can reproduce by both asexual agametic reproduction and sexual reproduction must transmit or re-establish their germ line post-embryonically. Although such a dual reproductive mode has evolved repeatedly among animals, how asexually produced individuals establish their germ line remains poorly understood in most groups. We investigated germ line development in the annelid Pristina leidyi, a species that typically reproduces asexually by paratomic fission, intercalating a new tail and head in the middle of the body followed by splitting. We found that in fissioning individuals, gonads occur in anterior segments in the anterior-most individual as well as in new heads forming within fission zones. Homologs of the germ line/multipotency genes piwi, vasa, and nanos are expressed in the gonads, as well as in proliferative tissues including the posterior growth zone, fission zone, and regeneration blastema. In fissioning animals, certain cells on the ventral nerve cord express a homolog of piwi, are abundant near fission zones, and sometimes make contact with gonads. Such cells are typically undetectable near the blastema and posterior growth zone. Time-lapse imaging provides direct evidence that cells on the ventral nerve cord migrate preferentially towards fission zones. Our findings indicate that gonads form routinely in fissioning individuals, that a population of piwi-positive cells on the ventral nerve cord is associated with fission and gonads, and that cells resembling these piwi-positive cells migrate along the ventral nerve cord. We suggest that the piwi-positive ventral cells are germ cells that transmit the germ line across asexually produced individuals via migration along the ventral nerve cord. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Sexual Fantasy and Masturbation Among Asexual Individuals: An In-Depth Exploration.

    Science.gov (United States)

    Yule, Morag A; Brotto, Lori A; Gorzalka, Boris B

    2017-01-01

    Human asexuality is generally defined as a lack of sexual attraction. We used online questionnaires to investigate reasons for masturbation, and explored and compared the contents of sexual fantasies of asexual individuals (identified using the Asexual Identification Scale) with those of sexual individuals. A total of 351 asexual participants (292 women, 59 men) and 388 sexual participants (221 women, 167 men) participated. Asexual women were significantly less likely to masturbate than sexual women, sexual men, and asexual men. Asexual women were less likely to report masturbating for sexual pleasure or fun than their sexual counterparts, and asexual men were less likely to report masturbating for sexual pleasure than sexual men. Both asexual women and men were significantly more likely than sexual women and men to report that they had never had a sexual fantasy. Of those who have had a sexual fantasy, asexual women and men were significantly more likely to endorse the response "my fantasies do not involve other people" compared to sexual participants, and consistently scored each sexual fantasy on a questionnaire as being less sexually exciting than did sexual participants. When using an open-ended format, asexual participants were more likely to report having fantasies about sexual activities that did not involve themselves, and were less likely to fantasize about topics such as group sex, public sex, and having an affair. Interestingly, there was a large amount of overlap between sexual fantasies of asexual and sexual participants. Notably, both asexual and sexual participants (both men and women) were equally likely to fantasize about topics such as fetishes and BDSM.

  5. Hybrid asexuality as a primary postzygotic barrier between nascent species: on the interconnection between asexuality, hybridization and speciation

    Czech Academy of Sciences Publication Activity Database

    Janko, K.; Pačes, J.; Wilkinson-Herbots, H.; Costa, R. J.; Roslein, Jan; Drozd, P.; Iakovenko, N.; Rídl, J.; Hroudová, M.; Kočí, J.; Reifová, R.; Šlechtová, V.; Choleva, L.

    2018-01-01

    Roč. 27, č. 1 (2018), s. 248-263 ISSN 0962-1083 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : pairwise nucleotide differences * mitochondrial-dna variation * multilocus genotype data * reproductive isolation * maximum-likelihood * loaches cobitis * migration model * gene flow * phylogenetic constraints * coalescence time * balance hypothesis * coalescence * evolution of asexuality * hybridization * phylogeography * speciation Subject RIV: EG - Zoology Impact factor: 6.086, year: 2016

  6. Coexistence of sexual individuals and genetically isolated asexual counterparts in a thrips.

    Science.gov (United States)

    Kobayashi, Kazuya; Yoshimura, Jin; Hasegawa, Eisuke

    2013-11-21

    Sex is a paradoxical phenomenon because it is less efficient compared with asexual reproduction. To resolve this paradox we need a direct comparison between sexual and asexual forms. In many organisms, however, sexual and asexual forms do not occur in the same habitat, or at the same time. In a few cases where sexual and asexual forms are found in a single population, some (though rare) genetic exchange is usually detected between the two forms. When genetic exchange occurs a direct comparison is impossible. Here we investigate a thrips exhibiting both sexual and asexual forms (lineages) that are morphologically indistinguishable. We examine if the two forms are genetically isolated. Phylogeny based on nuclear genes confirms that the sexual and asexual lineages are genetically differentiated. Thus we demonstrate that the current system has certain advantages over existing and previously used model systems in the evolution of sexual reproduction.

  7. Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis

    OpenAIRE

    Amat, I; Kacelnik, A; van Alphen, JJM; Desouhant, E; Bernstein, C

    2017-01-01

    Background Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals in...

  8. Plasmodium falciparum Calcium-Dependent Protein Kinase 2 Is Critical for Male Gametocyte Exflagellation but Not Essential for Asexual Proliferation

    Directory of Open Access Journals (Sweden)

    Abhisheka Bansal

    2017-10-01

    Full Text Available Drug development efforts have focused mostly on the asexual blood stages of the malaria parasite Plasmodium falciparum. Except for primaquine, which has its own limitations, there are no available drugs that target the transmission of the parasite to mosquitoes. Therefore, there is a need to validate new parasite proteins that can be targeted for blocking transmission. P. falciparum calcium-dependent protein kinases (PfCDPKs play critical roles at various stages of the parasite life cycle and, importantly, are absent in the human host. These features mark them as attractive drug targets. In this study, using CRISPR/Cas9 we successfully knocked out PfCDPK2 from blood-stage parasites, which was previously thought to be an indispensable protein. The growth rate of the PfCDPK2 knockout (KO parasites was similar to that of wild-type parasites, confirming that PfCDPK2 function is not essential for the asexual proliferation of the parasite in vitro. The mature male and female gametocytes of PfCDPK2 KO parasites become round after induction. However, they fail to infect female Anopheles stephensi mosquitoes due to a defect(s in male gametocyte exflagellation and possibly in female gametes.

  9. Multigeneration Inheritance through Fertile XX Carriers of an NR0B1 (DAX1 Locus Duplication in a Kindred of Females with Isolated XY Gonadal Dysgenesis

    Directory of Open Access Journals (Sweden)

    Michela Barbaro

    2012-01-01

    Full Text Available A 160 kb minimal common region in Xp21 has been determined as the cause of XY gonadal dysgenesis, if duplicated. The region contains the MAGEB genes and the NR0B1 gene; this is the candidate for gonadal dysgenesis if overexpressed. Most patients present gonadal dysgenesis within a more complex phenotype. However, few independent cases have recently been described presenting with isolated XY gonadal dysgenesis caused by relatively small NR0B1 locus duplications. We have identified another NR0B1 duplication in two sisters with isolated XY gonadal dysgenesis with an X-linked inheritance pattern. We performed X-inactivation studies in three fertile female carriers of three different small NR0B1 locus duplications identified by our group. The carrier mothers did not show obvious skewing of X-chromosome inactivation, suggesting that NR0B1 overexpression does not impair ovarian function. We furthermore emphasize the importance to investigate the NR0B1 locus also in patients with isolated XY gonadal dysgenesis.

  10. Increased progesterone production in cumulus-oocyte complexes of female mice sired by males with the Y-chromosome long arm deletion and its potential influence on fertilization efficiency.

    Science.gov (United States)

    Kotarska, Katarzyna; Galas, Jerzy; Przybyło, Małgorzata; Bilińska, Barbara; Styrna, Józefa

    2015-02-01

    It was revealed previously that B10.BR(Y(del)) females sired by males with the Y-chromosome long arm deletion differ from genetically identical B10.BR females sired by males with the intact Y chromosome. This is interpreted as a result of different epigenetic information which females of both groups inherit from their fathers. In the following study, we show that cumulus-oocyte complexes ovulated by B10.BR(Y(del)) females synthesize increased amounts of progesterone, which is important sperm stimulator. Because their extracellular matrix is excessively firm, the increased progesterone secretion belongs presumably to factors that compensate this feature enabling unchanged fertilization ratios. Described compensatory mechanism can act only on sperm of high quality, presenting proper receptors. Indeed, low proportion of sperm of Y(del) males that poorly fertilize B10.BR(Y(del)) oocytes demonstrates positive staining of membrane progesterone receptors. This proportion is significantly higher for sperm of control males that fertilize B10.BR(Y(del)) and B10.BR oocytes with the same efficiency. © The Author(s) 2014.

  11. Hybrid asexuality as a primary postzygotic barrier between nascent species: On the interconnection between asexuality, hybridization and speciation

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel; Pačes, Jan; Wilkinson-Herbots, H.; Costa, R. J.; Roslein, Jan; Drozd, P.; Iakovenko, Nataliia; Rídl, J.; Hroudová, M.; Kočí, Jan; Reifová, R.; Šlechtová, Věra; Choleva, Lukáš

    2018-01-01

    Roč. 27, č. 1 (2018), s. 248-263 ISSN 0962-1083 R&D Projects: GA AV ČR KJB600450902; GA MŠk EF15_003/0000460; GA ČR GA13-12580S; GA ČR GA206/09/1298; GA ČR GAP506/10/1155; GA ČR GJ15-19947Y Institutional support: RVO:67985904 Keywords : balance hypothesis * coalescence * ecolution of asexuality * hybridization Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 6.086, year: 2016

  12. The Effect of Elevated CO2 and Increased Temperature on in Vitro Fertilization Success and Initial Embryonic Development of Single Male:Female Crosses of Broad-Cast Spawning Corals at Mid- and High-Latitude Locations

    Directory of Open Access Journals (Sweden)

    Miriam Schutter

    2015-05-01

    Full Text Available The impact of global climate change on coral reefs is expected to be most profound at the sea surface, where fertilization and embryonic development of broadcast-spawning corals takes place. We examined the effect of increased temperature and elevated CO2 levels on the in vitro fertilization success and initial embryonic development of broadcast-spawning corals using a single male:female cross of three different species from mid- and high-latitude locations: Lyudao, Taiwan (22° N and Kochi, Japan (32° N. Eggs were fertilized under ambient conditions (27 °C and 500 μatm CO2 and under conditions predicted for 2100 (IPCC worst case scenario, 31 °C and 1000 μatm CO2. Fertilization success, abnormal development and early developmental success were determined for each sample. Increased temperature had a more profound influence than elevated CO2. In most cases, near-future warming caused a significant drop in early developmental success as a result of decreased fertilization success and/or increased abnormal development. The embryonic development of the male:female cross of A. hyacinthus from the high-latitude location was more sensitive to the increased temperature (+4 °C than the male:female cross of A. hyacinthus from the mid-latitude location. The response to the elevated CO2 level was small and highly variable, ranging from positive to negative responses. These results suggest that global warming is a more significant and universal stressor than ocean acidification on the early embryonic development of corals from mid- and high-latitude locations.

  13. Do cycle disturbances explain the age-related decline of female fertility? Cycle characteristics of women aged over 40 years compared with a reference population of young women.

    NARCIS (Netherlands)

    Zonneveld, P. van; Scheffer, G.J.; Broekmans, F.J.; Blankenstein, M.A.; Jong, F.H. de; Looman, C.W.; Habbema, J.D.F.; Velde, E.R. te

    2003-01-01

    BACKGROUND: The cause of declining fertility with age, in women who still have regular menstrual cycles, is not clear. METHODS: Follicle development, endometrial growth and hormonal patterns were evaluated in cycles of older women (aged 41-46 years; n = 26) who previously were normally fertile, and

  14. The exact distributions of F(IS under partial asexuality in small finite populations with mutation.

    Directory of Open Access Journals (Sweden)

    Solenn Stoeckel

    Full Text Available Reproductive systems like partial asexuality participate to shape the evolution of genetic diversity within populations, which is often quantified by the inbreeding coefficient F IS. Understanding how those mating systems impact the possible distributions of F IS values in theoretical populations helps to unravel forces shaping the evolution of real populations. We proposed a population genetics model based on genotypic states in a finite population with mutation. For populations with less than 400 individuals, we assessed the impact of the rates of asexuality on the full exact distributions of F IS, the probabilities of positive and negative F IS, the probabilities of fixation and the probabilities to observe changes in the sign of F IS over one generation. After an infinite number of generations, we distinguished three main patterns of effects of the rates of asexuality on genetic diversity that also varied according to the interactions of mutation and genetic drift. Even rare asexual events in mainly sexual populations impacted the balance between negative and positive F IS and the occurrence of extreme values. It also drastically modified the probability to change the sign of F IS value at one locus over one generation. When mutation prevailed over genetic drift, increasing rates of asexuality continuously increased the variance of F IS that reached its highest value in fully asexual populations. In consequence, even ancient asexual populations showed the entire F IS spectrum, including strong positive F IS. The prevalence of heterozygous loci only occurred in full asexual populations when genetic drift dominated.

  15. Effect of Female Body Mass Index on Oocyte Quantity in Fertility Treatments (IVF: Treatment Cycle Number Is a Possible Effect Modifier. A Register-Based Cohort Study.

    Directory of Open Access Journals (Sweden)

    Mette Wulf Christensen

    Full Text Available Overweight and obese women may require higher doses of gonadotrophin when undergoing In Vitro Fertilization Treatment (IVF. Consequently, one may expect a sub-optimal oocyte retrieval in the first treatment cycle and thus a larger compensation in gonadotrophin-dose in the following treatment-cycles and a more favorable outcome. The main objective was to explore if treatment cycle number modifies the outcome when investigating the effect of female Body Mass Index (BMI on oocyte quantity in IVF.A historical cohort study was conducted on 5,342 treatment-cycles during the period 1999-2009. Exclusion criteria were missing information on BMI or treatment type. Further, women were excluded if they had ovulated before oocyte retrieval. According to baseline BMI, women were divided into four categories following the World Health Organization standards. Multiple linear regressions analyses were performed accounting for the non-independence of ≥2 cycles in a woman.Stratification according to cycle number revealed a more suboptimal outcome in the first treatment- cycles than in the following cycles, suggesting a possible interaction or effect modification from cycle number or a factor related to cycle number. The median dose of total follicular stimulating hormone given to the four BMI groups could not straight forwardly explain the less optimal oocyte outcome observed in first treatment cycles. No statistically significant differences were observed in oocyte yield for underweight, overweight and obesity compared to normal weight women when analyzing all treatment-cycles. Overweight women had significantly fewer mature (MII oocytes (p = 0.009 than normal weight women, whereas no differences was observed for underweight and obese women.Our study suggests a possible interaction or effect modification related to treatment cycle number. Investigating the effects of BMI on IVF-results in first treatment-cycles alone should be carried out cautiously.

  16. Abortion legislation, maternal healthcare, fertility, female literacy, sanitation, violence against women and maternal deaths: a natural experiment in 32 Mexican states

    Science.gov (United States)

    Koch, Elard; Chireau, Monique; Pliego, Fernando; Stanford, Joseph; Haddad, Sebastian; Calhoun, Byron; Aracena, Paula; Bravo, Miguel; Gatica, Sebastián; Thorp, John

    2015-01-01

    Objective To test whether there is an association between abortion legislation and maternal mortality outcomes after controlling for other factors thought to influence maternal health. Design Population-based natural experiment. Setting and data sources Official maternal mortality data from 32 federal states of Mexico between 2002 and 2011. Main outcomes Maternal mortality ratio (MMR), MMR with any abortive outcome (MMRAO) and induced abortion mortality ratio (iAMR). Independent variables Abortion legislation grouped as less (n=18) or more permissive (n=14); constitutional amendment protecting the unborn (n=17); skilled attendance at birth; all-abortion hospitalisation ratio; low birth weight rate; contraceptive use; total fertility rates (TFR); clean water; sanitation; female literacy rate and intimate-partner violence. Main results Over the 10-year period, states with less permissive abortion legislation exhibited lower MMR (38.3 vs 49.6; pabortion hospitalisation ratio (β=−0.566 to −0.962), clean water (β=−0.048 to −0.730), sanitation (β=−0.052 to −0.758) and intimate-partner violence (β=0.085 to 0.755). TFR showed an inverse association with MMR (β=−14.329) and MMRAO (β=−1.750) and a direct association with iAMR (β=1.383). Altogether, these factors accounted for (R2) 51–88% of the variance among states in overall mortality rates. No statistically independent effect was observed for abortion legislation, constitutional amendment or other covariates. Conclusions Although less permissive states exhibited consistently lower maternal mortality rates, this finding was not explained by abortion legislation itself. Rather, these differences were explained by other independent factors, which appeared to have a more favourable distribution in these states. PMID:25712817

  17. Abortion legislation, maternal healthcare, fertility, female literacy, sanitation, violence against women and maternal deaths: a natural experiment in 32 Mexican states.

    Science.gov (United States)

    Koch, Elard; Chireau, Monique; Pliego, Fernando; Stanford, Joseph; Haddad, Sebastian; Calhoun, Byron; Aracena, Paula; Bravo, Miguel; Gatica, Sebastián; Thorp, John

    2015-02-23

    To test whether there is an association between abortion legislation and maternal mortality outcomes after controlling for other factors thought to influence maternal health. Population-based natural experiment. Official maternal mortality data from 32 federal states of Mexico between 2002 and 2011. Maternal mortality ratio (MMR), MMR with any abortive outcome (MMRAO) and induced abortion mortality ratio (iAMR). Abortion legislation grouped as less (n=18) or more permissive (n=14); constitutional amendment protecting the unborn (n=17); skilled attendance at birth; all-abortion hospitalisation ratio; low birth weight rate; contraceptive use; total fertility rates (TFR); clean water; sanitation; female literacy rate and intimate-partner violence. Over the 10-year period, states with less permissive abortion legislation exhibited lower MMR (38.3 vs 49.6; ppermissive states. Multivariate regression models estimating effect sizes (β-coefficients) for mortality outcomes showed independent associations (p values between 0.001 and 0.055) with female literacy (β=-0.061 to -1.100), skilled attendance at birth (β=-0.032 to -0.427), low birth weight (β=0.149 to 2.166), all-abortion hospitalisation ratio (β=-0.566 to -0.962), clean water (β=-0.048 to -0.730), sanitation (β=-0.052 to -0.758) and intimate-partner violence (β=0.085 to 0.755). TFR showed an inverse association with MMR (β=-14.329) and MMRAO (β=-1.750) and a direct association with iAMR (β=1.383). Altogether, these factors accounted for (R(2)) 51-88% of the variance among states in overall mortality rates. No statistically independent effect was observed for abortion legislation, constitutional amendment or other covariates. Although less permissive states exhibited consistently lower maternal mortality rates, this finding was not explained by abortion legislation itself. Rather, these differences were explained by other independent factors, which appeared to have a more favourable distribution in these

  18. Cancer and fertility: strategies to preserve fertility.

    Science.gov (United States)

    Diedrich, K; Fauser, B C J M; Devroey, P

    2011-03-01

    Fertility preservation is a key component of cancer management in young people. The Fourth Evian Annual Reproduction Workshop Meeting was held in April 2009 to discuss cancer and fertility in young adults. Specialists in oncology, assisted reproduction, embryology and clinical genetics presented published data and ongoing research on cancer and fertility, with particular focus on strategies to preserve fertility. This report is based on the expert presentations and group discussions, supplemented with publications from literature searches and the authors' knowledge. Fertility preservation should be considered for all young people undergoing potentially gonadotoxic cancer treatment. A variety of options are required to facilitate safe and effective fertility preservation for individual patients. Sperm banking is a simple and low-cost intervention. Embryo cryopreservation is the only established method of female fertility preservation. Oocyte cryopreservation offers a useful option for women without a male partner. Emergency ovarian stimulation and cryopreservation of ovarian tissue (followed by tissue transplantation or in-vitro maturation of oocytes) are experimental techniques for women who require urgent cancer treatment. Further prospective studies are required to validate cryopreservation of oocytes and ovarian tissue, in-vitro maturation of oocytes and new vitrification techniques and to identify any long-term sequelae of slow freezing of embryos. Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  19. Sexual dimorphism in white campion: deletion on the Y chromosome results in a floral asexual phenotype

    International Nuclear Information System (INIS)

    Farbos, I.; Veuskens, J.; Vyskot, B.; Oliveira, M.; Hinnisdaels, S.; Aghmir, A.; Mouras, A.; Negrutiu, I.

    1999-01-01

    White campion is a dioecious plant with heteromorphic X and Y sex chromosomes. In male plants, a filamentous structure replaces the pistil, while in female plants the stamens degenerate early in flower development. Asexual (asx) mutants, cumulating the two developmental defects that characterize the sexual dimorphism in this species, were produced by gamma ray irradiation of pollen and screening in the M1 generation. The mutants harbor a novel type of mutation affecting an early function in sporogenous/parietal cell differentiation within the anther. The function is called stamen-promoting function (SPF). The mutants are shown to result from interstitial deletions on the Y chromosome. We present evidence that such deletions tentatively cover the central domain on the (p)-arm of the Y chromosome (Y2 region). By comparing stamen development in wild-type female and asx mutant flowers we show that they share the same block in anther development, which results in the production of vestigial anthers. The data suggest that the SPF, a key function(s) controlling the sporogenous/parietal specialization in premeiotic anthers, is genuinely missing in females (XX constitution). We argue that this is the earliest function in the male program that is Y-linked and is likely responsible for ''male dimorphism'' (sexual dimorphism in the third floral whorl) in white campion. More generally, the reported results improve our knowledge of the structural and functional organization of the Y chromosome and favor the view that sex determination in this species results primarily from a trigger signal on the Y chromosome (Y1 region) that suppresses female development. The default state is therefore the ancestral hermaphroditic state

  20. Discovery of human posterior head 20 (hPH20) and homo sapiens sperm acrosome associated 1 (hSPACA1) immunocontraceptive epitopes and their effects on fertility in male and female mice.

    Science.gov (United States)

    Chen, Xuemei; Liu, Xiaodong; Ren, Xiuhua; Li, Xuewu; Wang, Li; Zang, Weidong

    2016-03-01

    The key goals of immunocontraception research are to obtain full contraceptive effects using vaccines administered to both males and females. Current research concerning human anti-sperm contraceptive vaccines is focused on delineating infertility-related epitopes to avoid autoimmune disease. We constructed phage-display peptide libraries to select epitope peptides derived from human posterior head 20 (hPH20) and homo sapiens sperm acrosome associated 1 (hSPACA1) using sera collected from infertile women harbouring anti-sperm antibodies. Following five rounds of selection, positive colonies were reconfirmed for reactivity with the immunoinfertile sera. We biopanned and analysed the chemical properties of four epitope peptides, named P82, Sa6, Sa37 and Sa76. Synthetic peptides were made and coupled to either bovine serum albumin (BSA) or ovalbumin. We used the BSA-conjugated peptides to immunise BALB/c mice and examined the effects on fertility in female and male mice. The synthetic peptides generated a sperm-specific antibody response in female and male mice that caused a contraceptive state. The immunocontraceptive effect was reversible and, with the disappearance of peptide-specific antibodies, there was complete restoration of fertility. Vaccinations using P82, Sa6 and Sa76 peptides resulted in no apparent side effects. Thus, it is efficient and practical to identify epitope peptide candidates by phage display. These peptides may find clinical application in the specific diagnosis and treatment of male and female infertility and contraceptive vaccine development.

  1. Sexy males and sexless females: the origin of triploid apomicts.

    Science.gov (United States)

    Muralidhar, P; Haig, D

    2017-05-01

    Apomixis and polyploidy are closely associated in angiosperms, but the evolutionary reason for this association is unknown. Taraxacum officinale, the common dandelion, exists both as diploid sexuals and triploid apomicts. Here, in the context of T. officinale, we provide a model of the evolution of triploid apomicts from diploid sexuals. We posit an apomictic allele that arrests female meiosis in diploids, so that the plant produces diploid egg cells that can develop without fertilization, but haploid pollen. We propose occasional fertilization of diploid egg cells by haploid pollen, resulting in triploid apomicts that produce triploid egg cells but largely nonfunctional pollen. The irreversibility of this process renders diploid partial apomicts evolutionarily short-lived, and results in fixation of triploid apomicts except when they suffer extreme selective disadvantages. Our model can account for the high genetic diversity found in T. officinale triploid populations, because recombinant haploid pollen produced by diploids allows the apomictic allele to spread onto many genetic backgrounds. This leads to multiple clonal lineages in the newly apomictic population, and thereby alleviates some of the usual pitfalls of asexual reproduction.

  2. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Fertil Steril. 2013; 100:1224-31. Chow EJ, et al. Pregnancy after chemotherapy in male and female ... Cancer . Urology. 2016;91:190-6. Loren AW, et al. Fertility preservation for patients with cancer: American ...

  3. Hybrid asexuality as a primary postzygotic barrier between nascent species: On the interconnection between asexuality, hybridization and speciation

    Czech Academy of Sciences Publication Activity Database

    Janko, K.; Pačes, Jan; Wilkinson-Herbots, H.; Costa, R. J.; Roslein, J.; Drozd, P.; Iakovenko, N.; Rídl, Jakub; Hroudová, Miluše; Kočí, J.; Reifová, R.; Šlechtová, V.; Choleva, L.

    2018-01-01

    Roč. 27, č. 1 (2018), s. 248-263 ISSN 0962-1083 R&D Projects: GA AV ČR KJB600450902; GA MŠk(CZ) LM2015047; GA ČR GA13-12580S; GA ČR GA206/09/1298; GA ČR GAP506/10/1155; GA ČR GJ15-19947Y; GA MŠk EF15_003/0000460 Institutional support: RVO:68378050 ; RVO:67985904 Keywords : balance hypothesis * coalescence * evolution of asexuality * hybridization * phylogeography * speciation Subject RIV: CE - Biochemistry OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 6.086, year: 2016

  4. Using web-based and paper-based questionnaires for collecting data on fertility issues among female childhood cancer survivors: differences in response characteristics.

    Science.gov (United States)

    van den Berg, Marleen H; Overbeek, Annelies; van der Pal, Helena J; Versluys, A Birgitta; Bresters, Dorine; van Leeuwen, Flora E; Lambalk, Cornelis B; Kaspers, Gertjan J L; van Dulmen-den Broeder, Eline

    2011-09-29

    Web-based questionnaires have become increasingly popular in health research. However, reported response rates vary and response bias may be introduced. The aim of this study was to evaluate whether sending a mixed invitation (paper-based together with Web-based questionnaire) rather than a Web-only invitation (Web-based questionnaire only) results in higher response and participation rates for female childhood cancer survivors filling out a questionnaire on fertility issues. In addition, differences in type of response and characteristics of the responders and nonresponders were investigated. Moreover, factors influencing preferences for either the Web- or paper-based version of the questionnaire were examined. This study is part of a nationwide study on reproductive function, ovarian reserve, and risk of premature menopause in female childhood cancer survivors. The Web-based version of the questionnaire was available for participants through the Internet by means of a personalized user name and password. Participants were randomly selected to receive either a mixed invitation (paper-based questionnaire together with log-in details for Web-based questionnaire, n = 137) or a Web-only invitation (log-in details only, n = 140). Furthermore, the latter group could request a paper-based version of the questionnaire by filling out a form. Overall response rates were comparable in both randomization groups (83% mixed invitation group vs 89% in Web-only invitation group, P = .20). In addition, participation rates appeared not to differ (66% or 90/137, mixed invitation group vs 59% or 83/140, Web-only invitation group, P =.27). However, in the mixed invitation group, significantly more respondents filled out the paper-based questionnaire compared with the Web-only invitation group (83% or 75/90 and 65% or 54/83, respectively, P = .01). The 44 women who filled out the Web-based version of the questionnaire had a higher educational level than the 129 women who filled out the

  5. Epidemiology of asexuality induced by the endosymbiotic Wolbachia across phytophagous wasp species: host plant specialization matters.

    Science.gov (United States)

    Boivin, T; Henri, H; Vavre, F; Gidoin, C; Veber, P; Candau, J-N; Magnoux, E; Roques, A; Auger-Rozenberg, M-A

    2014-05-01

    Among eukaryotes, sexual reproduction is by far the most predominant mode of reproduction. However, some systems maintaining sexuality appear particularly labile and raise intriguing questions on the evolutionary routes to asexuality. Thelytokous parthenogenesis is a form of spontaneous loss of sexuality leading to strong distortion of sex ratio towards females and resulting from mutation, hybridization or infection by bacterial endosymbionts. We investigated whether ecological specialization is a likely mechanism of spread of thelytoky within insect communities. Focusing on the highly specialized genus Megastigmus (Hymenoptera: Torymidae), we first performed a large literature survey to examine the distribution of thelytoky in these wasps across their respective obligate host plant families. Second, we tested for thelytoky caused by endosymbionts by screening in 15 arrhenotokous and 10 thelytokous species for Wolbachia, Cardinium, Arsenophonus and Rickettsia endosymbionts and by performing antibiotic treatments. Finally, we performed phylogenetic reconstructions using multilocus sequence typing (MLST) to examine the evolution of endosymbiont-mediated thelytoky in Megastigmus and its possible connections to host plant specialization. We demonstrate that thelytoky evolved from ancestral arrhenotoky through the horizontal transmission and the fixation of the parthenogenesis-inducing Wolbachia. We find that ecological specialization in Wolbachia's hosts was probably a critical driving force for Wolbachia infection and spread of thelytoky, but also a constraint. Our work further reinforces the hypothesis that community structure of insects is a major driver of the epidemiology of endosymbionts and that competitive interactions among closely related species may facilitate their horizontal transmission. © 2014 John Wiley & Sons Ltd.

  6. Natural epigenetic variation contributes to heritable flowering divergence in a widespread asexual dandelion lineage

    NARCIS (Netherlands)

    Wilschut, R.A.; Oplaat, C.; Snoek, B.; Kirschner, J.; Verhoeven, K.J.F.

    2016-01-01

    Epigenetic variation has been proposed to contribute to the success of asexual plants, either as a contributor to phenotypic plasticity or by enabling transient adaptation via selection on transgenerationally stable, but reversible, epialleles. While recent studies in experimental plant populations

  7. Data from: Natural epigenetic variation contributes to heritable flowering divergence in a widespread asexual dandelion lineage

    NARCIS (Netherlands)

    Wilschut, Rutger; Oplaat, C.; Snoek, L.B.; Kirschner, J.; Verhoeven, K.J.F.

    2015-01-01

    Epigenetic variation has been proposed to contribute to the success of asexual plants, either as a contributor to phenotypic plasticity or by enabling transient adaptation via selection on transgenerationally stable, but reversible, epialleles. While recent studies in experimental plant populations

  8. Improving the reliability of female fertility breeding values using type and milk yield traits that predict energy status in Australian Holstein cattle.

    Science.gov (United States)

    González-Recio, O; Haile-Mariam, M; Pryce, J E

    2016-01-01

    The objectives of this study were (1) to propose changing the selection criteria trait for evaluating fertility in Australia from calving interval to conception rate at d 42 after the beginning of the mating season and (2) to use type traits as early fertility predictors, to increase the reliability of estimated breeding values for fertility. The breeding goal in Australia is conception within 6 wk of the start of the mating season. Currently, the Australian model to predict fertility breeding values (expressed as a linear transformation of calving interval) is a multitrait model that includes calving interval (CVI), lactation length (LL), calving to first service (CFS), first nonreturn rate (FNRR), and conception rate. However, CVI has a lower genetic correlation with the breeding goal (conception within 6 wk of the start of the mating season) than conception rate. Milk yield, type, and fertility data from 164,318 cow sired by 4,766 bulls were used. Principal component analysis and genetic correlation estimates between type and fertility traits were used to select type traits that could subsequently be used in a multitrait analysis. Angularity, foot angle, and pin set were chosen as type traits to include in an index with the traits that are included in the multitrait fertility model: CVI, LL, CFS, FNRR, and conception rate at d 42 (CR42). An index with these 8 traits is expected to achieve an average bull first proof reliability of 0.60 on the breeding objective (conception within 6 wk of the start of the mating season) compared with reliabilities of 0.39 and 0.45 for CR42 only or the current 5-trait Australian model. Subsequently, we used the first eigenvector of a principal component analysis with udder texture, bone quality, angularity, and body condition score to calculate an energy status indicator trait. The inclusion of the energy status indicator trait composite in a multitrait index with CVI, LL, CFS, FNRR, and CR42 achieved a 12-point increase in

  9. Hispanic Adolescent Fertility.

    Science.gov (United States)

    Darabi, Katherine F.; And Others

    1986-01-01

    Discusses fertility of Hispanic adolescents in the United States. Summarizes what is known about sexuality, contraception, pregnancy, and childbearing among male and female Hispanics of various countries of origin. Indicates Hispanic adolescent birthrates fall between those of non-Hispanic Whites and Blacks, but there is considerable within-group…

  10. A combined approach to heat stress effect on male fertility in Nasonia vitripennis: from the physiological consequences on spermatogenesis to the reproductive adjustment of females mated with stressed males.

    Directory of Open Access Journals (Sweden)

    Marlène Chirault

    Full Text Available In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological control agents, such as parasitic wasps used to control crop pests. Here Nasonia vitripennis, a parasitic wasp of various fly species, was studied to test the effects of 24h-heat stress applied during the first pupal stage on male fertility. Results showed that only primary spermatocytes were present at the first pupal stage in all cysts of the testes. Heat stress caused a delay in spermatogenesis during development and a significant decrease in sperm stock at emergence. Females mated with these heat-stressed males showed a reduce sperm count stored in their spermatheca. Females did not appear to distinguish heat-stressed from control males and did not remate more frequently to compensate for the lack of sperm transferred. As a result, females mated with heat-stressed males produced a suboptimal lifetime offspring sex ratio compared to those mated with control males. This could further impact the population dynamics of this species. N. vitripennis appears to be an interesting biological model to study the mechanisms of subfertility and its consequence on female reproductive strategies and provides new research perspectives in both invertebrates and vertebrates.

  11. A combined approach to heat stress effect on male fertility in Nasonia vitripennis: from the physiological consequences on spermatogenesis to the reproductive adjustment of females mated with stressed males.

    Science.gov (United States)

    Chirault, Marlène; Lucas, Christophe; Goubault, Marlène; Chevrier, Claude; Bressac, Christophe; Lécureuil, Charlotte

    2015-01-01

    In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological control agents, such as parasitic wasps used to control crop pests. Here Nasonia vitripennis, a parasitic wasp of various fly species, was studied to test the effects of 24h-heat stress applied during the first pupal stage on male fertility. Results showed that only primary spermatocytes were present at the first pupal stage in all cysts of the testes. Heat stress caused a delay in spermatogenesis during development and a significant decrease in sperm stock at emergence. Females mated with these heat-stressed males showed a reduce sperm count stored in their spermatheca. Females did not appear to distinguish heat-stressed from control males and did not remate more frequently to compensate for the lack of sperm transferred. As a result, females mated with heat-stressed males produced a suboptimal lifetime offspring sex ratio compared to those mated with control males. This could further impact the population dynamics of this species. N. vitripennis appears to be an interesting biological model to study the mechanisms of subfertility and its consequence on female reproductive strategies and provides new research perspectives in both invertebrates and vertebrates.

  12. Let us not be unfair to asexuals: their ephemerality may be explained by neutral models without invoking any evolutionary constraints of asexuality

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel

    2014-01-01

    Roč. 68, č. 2 (2014), s. 569-576 ISSN 0014-3820 R&D Projects: GA ČR GA13-12580S Institutional support: RVO:67985904 Keywords : age of clones * asexuality * clonal turnover Subject RIV: EG - Zoology Impact factor: 4.612, year: 2014

  13. Nano Fertilizers

    Directory of Open Access Journals (Sweden)

    Hatice DAĞHAN

    2017-06-01

    Full Text Available Agricultural land is decreasing day by day due to erosion, environmental pollution, unconscious irrigation and fertilization. On the other hand, it is necessary to increase agricultural production in order to meet the needs of the developing industry as well as the nutritional needs of the growing population. In the recent years, nano fertilizers have begun to be produced to obtain the highest amount and quality of production from the unit area. Previous research shows that nano fertilizers cause an increase in the use efficiency of plant nutrients, reduce soil toxicity, minimize the potential adverse effects of excessive chemical fertilizer use, and reduce fertilizer application frequency. Nano fertilizers are important in agriculture to increase crop yield and nutrient use efficiency, and to reduce excessive use ofchemical fertilizers. The most important properties of these fertilizers are that they contain one or more of macro and micronutrients, they can be applied frequently in small amounts and are environmentally friendly. However, when applied at high doses, they exhibit decreasing effects on plant growth and crop yields, similar to chemical fertilizers. In this review, the definition, importan ce, and classification of nano fertilizers, their application in plant production, advantages and disadvantages and the results obtained in this field were discussed.

  14. Horizontal transfer generates genetic variation in an asexual pathogen

    Directory of Open Access Journals (Sweden)

    Xiaoqiu Huang

    2014-10-01

    Full Text Available There are major gaps in the understanding of how genetic variation is generated in the asexual pathogen Verticillium dahliae. On the one hand, V. dahliae is a haploid organism that reproduces clonally. On the other hand, single-nucleotide polymorphisms and chromosomal rearrangements were found between V. dahliae strains. Lineage-specific (LS regions comprising about 5% of the genome are highly variable between V. dahliae strains. Nonetheless, it is unknown whether horizontal gene transfer plays a major role in generating genetic variation in V. dahliae. Here, we analyzed a previously sequenced V. dahliae population of nine strains from various geographical locations and hosts. We found highly homologous elements in LS regions of each strain; LS regions of V. dahliae strain JR2 are much richer in highly homologous elements than the core genome. In addition, we discovered, in LS regions of JR2, several structural forms of nonhomologous recombination, and two or three homologous sequence types of each form, with almost each sequence type present in an LS region of another strain. A large section of one of the forms is known to be horizontally transferred between V. dahliae strains. We unexpectedly found that 350 kilobases of dynamic LS regions were much more conserved than the core genome between V. dahliae and a closely related species (V. albo-atrum, suggesting that these LS regions were horizontally transferred recently. Our results support the view that genetic variation in LS regions is generated by horizontal transfer between strains, and by chromosomal reshuffling reported previously.

  15. Distribution of the FMR1 gene in females by race/ethnicity: women with diminished ovarian reserve versus women with normal fertility (SWAN study).

    Science.gov (United States)

    Pastore, Lisa M; Young, Steven L; Manichaikul, Ani; Baker, Valerie L; Wang, Xin Q; Finkelstein, Joel S

    2017-01-01

    To study whether reported, but inconsistent, associations between the FMR1 CGG repeat lengths in the intermediate, high normal, or low normal range differentiate women diagnosed with diminished ovarian reserve (DOR) from population controls and whether associations vary by race/ethnic group. Case-control study. Academic and private fertility clinics. DOR cases (n = 129; 95 Whites, 22 Asian, 12 other) from five U.S. fertility clinics were clinically diagnosed, with regular menses and no fragile X syndrome family history. Normal fertility controls (n = 803; 386 Whites, 219 African-Americans, 102 Japanese, 96 Chinese) from the United States-based SWAN Study had one or more menstrual period in the 3 months pre-enrollment, one or more pregnancy, no history of infertility or hormone therapy, and menopause ≥46 years. Previously, the SWAN Chinese and Japanese groups had similar FMR1 CGG repeat lengths, thus they were combined. None. FMR1 CGG repeat lengths. Median CGG repeats were nearly identical by case/control group. DOR cases had fewer CGG repeats in the shorter FMR1 allele than controls among Whites, but this was not significant among Asians. White cases had fewer CGG repeats in the shorter allele than Asian cases. No significant differences were found in the high normal/intermediate range between cases and controls or by race/ethnic group within cases in the longer allele. This study refutes prior reports of an association between DOR and high normal/intermediate repeats and confirms an association between DOR and low normal repeats in Whites. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  16. Effect of Female Body Mass Index on Oocyte Quantity in Fertility Treatments (IVF): Treatment Cycle Number Is a Possible Effect Modifier. A Register-Based Cohort Study

    DEFF Research Database (Denmark)

    Christensen, Mette Wulf; Ingerslev, Hans Jakob; Degn, Birte

    2016-01-01

    linear regressions analyses were performed accounting for the non-independence of ≥2 cycles in a woman. RESULTS: Stratification according to cycle number revealed a more suboptimal outcome in the first treatment- cycles than in the following cycles, suggesting a possible interaction or effect......INTRODUCTION: Overweight and obese women may require higher doses of gonadotrophin when undergoing In Vitro Fertilization Treatment (IVF). Consequently, one may expect a sub-optimal oocyte retrieval in the first treatment cycle and thus a larger compensation in gonadotrophin-dose in the following...

  17. Collaborative work on evaluation of ovarian toxicity. 13) Two- or four-week repeated dose studies and fertility study of PPAR alpha/gamma dual agonist in female rats.

    Science.gov (United States)

    Sato, Norihiro; Uchida, Keisuke; Nakajima, Mikio; Watanabe, Atsushi; Kohira, Terutomo

    2009-01-01

    The main focus of this study was to determine the optimal dosing period in a repeated dose toxicity study based on toxic effects as assessed by ovarian morphological changes. To assess morphological and functional changes induced in the ovary by a peroxisome proliferator-activated receptor (PPAR) alpha/gamma dual agonist, the compound was administered to female rats at dose levels of 0, 4, 20, and 100 mg/kg/day in a repeated dose toxicity study for 2 or 4 weeks, and from 2 weeks prior to mating to Day 7 of pregnancy in a female fertility study. In the repeated dose toxicity study, an increase in atresia of large follicles, a decrease in corpora lutea, and an increase in stromal cells were observed in the treated groups. In addition, the granulosa cell exfoliations into antrum of large follicles and corpora lutea with retained oocyte are morphological characteristics induced by this compound, and they might be related with abnormal condition of ovulation. In the female fertility study, the pregnancy rate tended to decrease in the 100 mg/kg/day group. At necropsy, decreases in the number of corpora lutea, implantations and live embryos were noted in the 20 and 100 mg/kg/day group. No changes were observed in animals given 4 mg/kg/day. These findings indicated that histopathological changes in the ovary are important endpoints for evaluation of drugs inducing ovarian damage. In conclusion, a 2-week administration period is sufficient to detect ovarian toxicity of this test compound in the repeated dose toxicity study.

  18. Asexual sporulation facilitates adaptation: The emergence of azole resistance in Aspergillus fumigatus.

    Science.gov (United States)

    Zhang, Jianhua; Debets, Alfons J M; Verweij, Paul E; Melchers, Willem J G; Zwaan, Bas J; Schoustra, Sijmen E

    2015-10-01

    Understanding the occurrence and spread of azole resistance in Aspergillus fumigatus is crucial for public health. It has been hypothesized that asexual sporulation, which is abundant in nature, is essential for phenotypic expression of azole resistance mutations in A. fumigatus facilitating subsequent spread through natural selection. Furthermore, the disease aspergilloma is associated with asexual sporulation within the lungs of patients and the emergence of azole resistance. This study assessed the evolutionary advantage of asexual sporulation by growing the fungus under pressure of one of five different azole fungicides over seven weeks and by comparing the rate of adaptation between scenarios of culturing with and without asexual sporulation. Results unequivocally show that asexual sporulation facilitates adaptation. This can be explained by the combination of more effective selection because of the transition from a multicellular to a unicellular stage, and by increased mutation supply due to the production of spores, which involves numerous mitotic divisions. Insights from this study are essential to unravel the resistance mechanisms of sporulating pathogens to chemical compounds and disease agents in general, and for designing strategies that prevent or overcome the emerging threat of azole resistance in particular. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  19. Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis.

    Science.gov (United States)

    Amat, Isabelle; van Alphen, Jacques J M; Kacelnik, Alex; Desouhant, Emmanuel; Bernstein, Carlos

    2017-01-01

    Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals instead are common in anthropic environments (e.g., grain stores) where host outbreaks offer periods when egg-load is the main constraint on reproductive output. We present a meta-analysis of known adaptations to these habitats. Differences in behavior, physiology and life-history traits between sexual and asexual wasps were standardized in term of effect size (Cohen's d value; Cohen, 1988). Seeking consilience from the differences between multiple traits, we found that sexuals invest more in longevity at the expense of egg-load, are more mobile, and display higher plasticity in response to thermal variability than asexual counterparts. Thus, each form has consistent multiple adaptations to the ecological circumstances in the contrasting environments.

  20. Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Isabelle Amat

    2017-09-01

    Full Text Available Background Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals instead are common in anthropic environments (e.g., grain stores where host outbreaks offer periods when egg-load is the main constraint on reproductive output. Methods We present a meta-analysis of known adaptations to these habitats. Differences in behavior, physiology and life-history traits between sexual and asexual wasps were standardized in term of effect size (Cohen’s d value; Cohen, 1988. Results Seeking consilience from the differences between multiple traits, we found that sexuals invest more in longevity at the expense of egg-load, are more mobile, and display higher plasticity in response to thermal variability than asexual counterparts. Discussion Thus, each form has consistent multiple adaptations to the ecological circumstances in the contrasting environments.

  1. Mutation accumulation and fitness effects in hybridogenetic populations: a comparison to sexual and asexual systems

    Directory of Open Access Journals (Sweden)

    Bagheri Homayoun C

    2007-05-01

    Full Text Available Abstract Background Female only unisexual vertebrates that reproduce by hybridogenesis show an unusual genetic composition. They are of hybrid origin but show no recombination between the genomes of their parental species. Instead, the paternal genome is discarded from the germline prior to meiosis, and gametes (eggs only contain solely unrecombined maternal genomes. Hence hybridogens only transmit maternally inherited mutations. Hybridity is restored each generation by backcrossing with males of the sexual parental species whose genome was eliminated. In contrast, recombining sexual species propagate an intermixed pool of mutations derived from the maternal and paternal parts of the genome. If mutation rates are lower in female gametes than males, it raises the possibility for lower mutation accumulation in a hybridogenetic population, and consequently, higher population fitness than its sexual counterpart. Results We show through Monte-Carlo simulations that at higher male to female mutation ratios, and sufficiently large population sizes, hybridogenetic populations can carry a lower mutation load than sexual species. This effect is more pronounced with synergistic forms of epistasis. Mutations accumulate faster on the sexual part of the genome, and with the purifying effects of epistasis, it makes it more difficult for mutations to be transmitted on the clonal part of the genome. In smaller populations, the same mechanism reduces the speed of Muller's Ratchet and the number of fixed mutations compared to similar asexual species. Conclusion Since mutation accumulation can be less pronounced in hybridogenetic populations, the question arises why hybridogenetic organisms are so scarce compared to sexual species. In considering this, it is likely that comparison of population fitnesses is not sufficient. Despite competition with the sexual parental species, hybrid populations are dependent on the maintenance of – and contact with – their

  2. The Key Role of Epigenetics in the Persistence of Asexual Lineages

    Directory of Open Access Journals (Sweden)

    Emilie Castonguay

    2012-01-01

    Full Text Available Asexual organisms, often perceived as evolutionary dead ends, can be long-lived and geographically widespread. We propose that epigenetic mechanisms could play a crucial role in the evolutionary persistence of these lineages. Genetically identical organisms could rely on phenotypic plasticity to face environmental variation. Epigenetic modifications could be the molecular mechanism enabling such phenotypic plasticity; they can be influenced by the environment and act at shorter timescales than mutation. Recent work on the asexual vertebrate Chrosomus eos-neogaeus (Pisces: Cyprinidae provides broad insights into the contribution of epigenetics in genetically identical individuals. We discuss the extension of these results to other asexual organisms, in particular those resulting from interspecific hybridizations. We finally develop on the evolutionary relevance of epigenetic variation in the context of heritability.

  3. Fertility desires and fertility outcomes.

    Science.gov (United States)

    Bracher, M; Santow, G

    1991-05-01

    An Australian 1-in-1000 national probability sample conducted in 1986 yielded 2547 women aged 20-59 who provided detailed life histories on marital unions, childbearing, and contraception. Age specific fertility rates, desired family size, differentials in desired family size, desired fertility and achieved fertility, and sequential family building are examined. The results indicate that the desired family size at 1st marriage has declined only slightly over the past 30 years. 3 children are generally desired, and ver few desire 2. The constance of fertility desires in contrasted with the fertilitydecline to below replacement levels. Several reasons are suggested for the desired family size: the desire is for a family size within the family tradition and modified by the desire to have 1 of each sex, the desire reflects less on intentions but more on normative pressure to become a parent. Marrying is self selecting on the desire for a traditional family of at least 2 children. There is a rising age at marriage as well as a decline in marriages. Desired family size exceeds completed fertility. Period factors and personal circumstances affect fertility intentions. Future inquires should explore the multiple factors relating to fertility, rather than in comparing fertility desires and actual fertility. The data collected on age specific fertility were comparable to official estimates. The fertility decline was evidenced in all groups except teenagers. The decline was nearly 50% for those 20-24 years between the 1050's-80's, 33% for ages 25-29. Marriage patterns explain this decline in part. Between 1971-76, women aged 20-25 were married 37 months out of 60 months in 1971-76 versus 25 out of 60 months in 1981-86. Within the 25 year age group, marital fertility has declined and unmarried fertility, which is low, has risen, Women in a marital union of any kind has remained stable. Fertility within de facto unions, which is lower than within marriage, is higher than

  4. Fertility outcomes in asthma

    DEFF Research Database (Denmark)

    Gade, Elisabeth Juul; Thomsen, Simon Francis; Lindenberg, Svend

    2016-01-01

    Evidence is increasing of an association between asthma and aspects of female reproduction. However, current knowledge is limited and furthermore relies on questionnaire studies or small populations. In a prospective observational cohort study to investigate whether time to pregnancy, the number...... of fertility treatments, and the number of successful pregnancies differ significantly between women with unexplained infertility with and without asthma.245 women with unexplained infertility (aged 23-45 years) underwent questionnaires and asthma and allergy testing while undergoing fertility treatment. 96...... women entering the study had either a former doctor's diagnosis of asthma or were diagnosed with asthma when included. After inclusion they were followed for a minimum of 12 months in fertility treatment, until they had a successful pregnancy, stopped treatment, or the observation ended.The likelihood...

  5. [Stress and fertility].

    Science.gov (United States)

    Ősapay, György; Ősapay, Klára

    2015-08-30

    In Western countries, sperm quality and fertility of men significantly worsened. Female infertility does not show a better trend either. Subtle defects in the reproductive functions can not be explained by the current methods, and "unexplained infertility" is becoming a more common diagnosis. Every year 1 million couples seek expensive and time consuming fertility treatment in the world. Deeper understanding of an unhealthy lifestyle and the environmental damages may lead to personalized treatments to increase the chance of conception.The effects of various stressors on the male and female reproductive performance were scientifically substantiated by Selye and coworkers in 1976. Cognitive therapy methods can be applied against emotional stressors, supplementation by antioxidants against reactive oxygen compounds, and administration of vitamins and trace elements, especially when deficiency is found, may help before medical intervention on a rational and economical way in the fight against infertility.

  6. Changes in genomic methylation patterns during the formation of triploid asexual dandelion lineages

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Van Dijk, P.J.; Biere, A.

    2010-01-01

    DNA methylation is an epigenetic mechanism that has the potential to affect plant phenotypes and that is responsive to environmental and genomic stresses such as hybridization and polyploidization. We explored de novo methylation variation that arises during the formation of triploid asexual

  7. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex

    NARCIS (Netherlands)

    Groenewald, M.; Groenewald, J.Z.; Harrington, T.C.; Abeln, E.C.A.; Crous, P.W.

    2006-01-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to

  8. Is meiosis a fundamental cause of inviability among sexual and asexual plants and animals?

    Science.gov (United States)

    Levitis, Daniel A; Zimmerman, Kolea; Pringle, Anne

    2017-08-16

    Differences in viability between asexually and sexually generated offspring strongly influence the selective advantage and therefore the prevalence of sexual reproduction (sex). However, no general principle predicts when sexual offspring will be more viable than asexual offspring. We hypothesize that when any kind of reproduction is based on a more complex cellular process, it will encompass more potential failure points, and therefore lower offspring viability. Asexual reproduction (asex) can be simpler than sex, when offspring are generated using only mitosis. However, when asex includes meiosis and meiotic restitution, gamete production is more complex than in sex. We test our hypothesis by comparing the viability of asexual and closely related sexual offspring across a wide range of plants and animals, and demonstrate that meiotic asex does result in lower viability than sex; without meiosis, asex is mechanistically simple and provides higher viability than sex. This phylogenetically robust pattern is supported in 42 of 44 comparisons drawn from diverse plants and animals, and is not explained by the other variables included in our model. Other mechanisms may impact viability, such as effects of reproductive mode on heterozygosity and subsequent viability, but we propose the complexity of cellular processes of reproduction, particularly meiosis, as a fundamental cause of early developmental failure and mortality. Meiosis, the leading cause of inviability in humans, emerges as a likely explanation of offspring inviability among diverse eukaryotes. © 2017 The Author(s).

  9. "Asexual propagation of a virulent clone complex in human and feline outbreak of sporotrichosis"

    NARCIS (Netherlands)

    Teixeira, Marcus de Melo; Rodrigues, Anderson Messias; Tsui, Clement K M; de Almeida, Luiz Gonzaga Paulo; Van Diepeningen, Anne D; Gerrits van den Ende, Bert; Fernandes, Geisa Ferreira; Kano, Rui; Hamelin, Richard C; Lopes-Bezerra, Leila Maria; Ribeiro Vasconcelos, Ana Tereza; de Hoog, Sybren; de Camargo, Zoilo Pires; Felipe, Maria Sueli Soares

    2014-01-01

    Sporotrichosis is one of the most frequent subcutaneous fungal infections to human and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual, as no sexual stage has ever

  10. Induction of cell death on Plasmodium falciparum asexual blood stages by Solanum nudum steroids

    DEFF Research Database (Denmark)

    López, Mary Luz; Vommaro, Rossiane; Zalis, Mariano

    2010-01-01

    Solanum nudum Dunal (Solanaceae) is a plant used in traditional medicine in Colombian Pacific Coast, from which five steroids denominated SNs have been isolated. The SNs compounds have antiplasmodial activity against asexual blood stages of Plasmodium falciparum strain 7G8 with an IC50 between 20...

  11. Ontology for the asexual development and anatomy of the colonial chordate Botryllus schlosseri.

    Directory of Open Access Journals (Sweden)

    Lucia Manni

    Full Text Available Ontologies provide an important resource to integrate information. For developmental biology and comparative anatomy studies, ontologies of a species are used to formalize and annotate data that are related to anatomical structures, their lineage and timing of development. Here, we have constructed the first ontology for anatomy and asexual development (blastogenesis of a bilaterian, the colonial tunicate Botryllus schlosseri. Tunicates, like Botryllus schlosseri, are non-vertebrates and the only chordate taxon species that reproduce both sexually and asexually. Their tadpole larval stage possesses structures characteristic of all chordates, i.e. a notochord, a dorsal neural tube, and gill slits. Larvae settle and metamorphose into individuals that are either solitary or colonial. The latter reproduce both sexually and asexually and these two reproductive modes lead to essentially the same adult body plan. The Botryllus schlosseri Ontology of Development and Anatomy (BODA will facilitate the comparison between both types of development. BODA uses the rules defined by the Open Biomedical Ontologies Foundry. It is based on studies that investigate the anatomy, blastogenesis and regeneration of this organism. BODA features allow the users to easily search and identify anatomical structures in the colony, to define the developmental stage, and to follow the morphogenetic events of a tissue and/or organ of interest throughout asexual development. We invite the scientific community to use this resource as a reference for the anatomy and developmental ontology of B. schlosseri and encourage recommendations for updates and improvements.

  12. Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides

    Science.gov (United States)

    The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plant...

  13. Female infertility

    International Nuclear Information System (INIS)

    Hall, D.A.; Yoder, I.

    1984-01-01

    Infertility, defined as 1 year of unprotected intercourse without conception, is becoming of increasingly important medical concern. Fertility in both the male and the female is at its peak in the twenties. Many couples today have postponed marriage and/or childbearing into their 30s until careers are established, but at that point fertility may be diminished. The current epidemic of venereal disease has been associated with an increasing incidence of tubal scarring. In addition, the use of intrauterine devices (IUDs) and birth control pills for contraception have let to later problems with pelvic inflammatory disease (PID) and ovulation disturbances. The problem of infertility intensifies as the number of babies available for adoption decreases. Therefore, it is estimated that approximately 10-20% of couples will eventually seek medical attention for an infertility-related problem. Fortunately, marked improvements in the results of tubal surgery are concurrently occurring secondary to refinements in microsurgical techniques, and many medical alternatives to induce ovulation are being developed. The male factor causes infertility in 30-40 % of couples, and the female factor is responsible in approximately 50% of couples. No cause is found in 10-20% of couples. This chapter discusses the role of coordinated imaging in the diagnosis and therapy of infertility in the female

  14. Cryptic sexual populations account for genetic diversity and ecological success in a widely distributed, asexual fungus-growing ant.

    Science.gov (United States)

    Rabeling, Christian; Gonzales, Omar; Schultz, Ted R; Bacci, Maurício; Garcia, Marcos V B; Verhaagh, Manfred; Ishak, Heather D; Mueller, Ulrich G

    2011-07-26

    Sex and recombination are central processes in life generating genetic diversity. Organisms that rely on asexual propagation risk extinction due to the loss of genetic diversity and the inability to adapt to changing environmental conditions. The fungus-growing ant species Mycocepurus smithii was thought to be obligately asexual because only parthenogenetic populations have been collected from widely separated geographic localities. Nonetheless, M. smithii is ecologically successful, with the most extensive distribution and the highest population densities of any fungus-growing ant. Here we report that M. smithii actually consists of a mosaic of asexual and sexual populations that are nonrandomly distributed geographically. The sexual populations cluster along the Rio Amazonas and the Rio Negro and appear to be the source of independently evolved and widely distributed asexual lineages, or clones. Either apomixis or automixis with central fusion and low recombination rates is inferred to be the cytogenetic mechanism underlying parthenogenesis in M. smithii. Males appear to be entirely absent from asexual populations, but their existence in sexual populations is indicated by the presence of sperm in the reproductive tracts of queens. A phylogenetic analysis of the genus suggests that M. smithii is monophyletic, rendering a hybrid origin of asexuality unlikely. Instead, a mitochondrial phylogeny of sexual and asexual populations suggests multiple independent origins of asexual reproduction, and a divergence-dating analysis indicates that M. smithii evolved 0.5-1.65 million years ago. Understanding the evolutionary origin and maintenance of asexual reproduction in this species contributes to a general understanding of the adaptive significance of sex.

  15. Fertility prognosis for infertile couples

    DEFF Research Database (Denmark)

    Bostofte, E; Bagger, P; Michael, A

    1993-01-01

    OBJECTIVE: To develop a fertility prognosis model for infertile couples. DESIGN: Prospective follow-up study. PARTICIPANTS: In the period November 30, 1977 to June 1, 1985, 321 consecutive couples were investigated for infertility at Hvidovre University Hospital. Investigation of the female...... MEASURE: The Cox regression model was used to predict the time required to conceive based on informations provided by fertility investigations. RESULTS: Three of 16 prognostic variables (the period of infertility, the female infertility factor, and the P-test) possess significant prognostic information...

  16. Relationships among body composition, circulating concentrations of leptin and follistatin, and the onset of puberty and fertility in young female sheep.

    Science.gov (United States)

    Rosales Nieto, C A; Thompson, A N; Macleay, C A; Briegel, J R; Hedger, M P; Ferguson, M B; Martin, G B

    2014-12-30

    The onset of puberty depends on the attainment of critical body mass, so should also be affected by increases in the rate of accumulation of muscle and adipose tissue. Adipose tissue and reproduction are linked by leptin. For muscle, a link has not yet been identified, although one possibility is follistatin. We assessed the relationships among circulating concentrations of follistatin and leptin and the rates of growth and accumulation of muscle and fat during pubertal development in female sheep. We used 326 animals with known phenotypic values for live weight (LW), depths of eye muscle (EMD) and fat (FAT), and known breeding values at post-weaning age for body mass (PWT) and depths of eye muscle (PEMD) and fat (PFAT). Leptin concentration was positively correlated with values for EMD, PEMD, FAT, PFAT, LW and PWT (Preproductive rate (Preproductive rate (Preproductive performance. We conclude that leptin and follistatin are probably both involved in effects of accelerated accumulation of muscle and adipose tissues on the onset of puberty. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Expression and putative function of fibronectin and its receptor (integrin alpha(5)beta(1)) in male and female gametes during bovine fertilization in vitro.

    Science.gov (United States)

    Thys, Mirjan; Nauwynck, Hans; Maes, Dominiek; Hoogewijs, Maarten; Vercauteren, Dries; Rijsselaere, Tom; Favoreel, Herman; Van Soom, Ann

    2009-09-01

    Fibronectin (Fn) is a 440 kDa glycoprotein assumed to participate in sperm-egg interaction in human. Recently, it has been demonstrated that Fn--when present during bovine IVF--strongly inhibits sperm penetration. The present study was conducted firstly to evaluate the expression of Fn and its integrin receptor (alpha(5)beta(1)) on male and female bovine gametes using indirect immunofluorescence and secondly, to determine the function of Fn during bovine IVF. Endogenous Fn was detected underneath the zona pellucida (ZP) and integrin alpha(5) on the oolemma of cumulus-denuded oocytes. Bovine spermatozoa displayed integrin alpha(5) at their equatorial segment after acrosome reaction. We established that the main inhibitory effect of exogenously supplemented Fn was located at the sperm-oolemma binding, with a (concurrent) effect on fusion, and this can probably be attributed to the binding of Fn to spermatozoa at the equatorial segment, as shown by means of Alexa Fluor 488-conjugated Fn. Combining these results, the inhibitory effect of exogenously supplemented Fn seemed to be exerted on the male gamete by binding to the exposed integrin alpha(5)beta(1) receptor after acrosome reaction. The presence of endogenous Fn underneath the ZP together with integrin alpha(5) expression on oolemma and acrosome-reacted (AR) sperm cell surface suggests a 'velcro' interaction between the endogenous Fn ligand and corresponding receptors on both (AR) sperm cell and oolemma, initiating sperm-egg binding.

  18. Nutrition and fertility.

    Science.gov (United States)

    Pinelli, G; Tagliabue, A

    2007-12-01

    The first studies about fertility and nutrition date back to the 70ies and already showed a strict relation among female fertility, weight and body composition. However, the mechanisms of this connection started to be explained only after leptin's discovery. According to some authors' opinion, leptin could interact with reproductive axis at multiple sites with stimulatory effects at the hypothalamus and pituitary and stimulatory or inhibitory actions at the gonads. Leptin could play a role in other physiologic processes such as menstruation and pregnancy, and could initiate the complex process of puberty. It has been showed that conditions in which nutritional status is suboptimal, such as eating disorders, exercise induced amenhorrea, functional hypothalamic amenhorrea and polycystic ovarian syndrome, are associated with abnormal leptin levels. These conditions, are characterized by severe changes in body composition and dietary habits. Since leptin is regulated by body composition and dietary factors, (such as energy intake and macronutrient composition), a strict connection between nutritional intake and fertility regulated by leptin is confirmed. This review focuses on the current knowledge about nutritional factors that influence leptin levels. Since clinical and subclinical nutritional imbalance can determine the development and the maintenance of neuroendocrine and metabolic aberrations, studies on fertility need a deeper attention about dietary habits and nutritional status.

  19. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Ethics Committee of the American Society for Reproductive Medicine. Fertility preservation and reproduction in patients facing gonadotoxic therapies: a committee opinion. Fertil Steril. 2013; 100:1224-31. Chow EJ, et al. Pregnancy after chemotherapy in male and female survivors of ...

  20. Asexual queen succession mediates an accelerated colony life cycle in the termite Silvestritermes minutus

    Czech Academy of Sciences Publication Activity Database

    Fougeyrollas, R.; Křivánek, Jan; Roy, V.; Dolejšová, Klára; Frechault, S.; Roisin, Y.; Hanus, Robert; Sillam-Dusses, D.

    2017-01-01

    Roč. 26, č. 12 (2017), s. 3295-3308 ISSN 0962-1083 R&D Projects: GA ČR(CZ) GA14-12774S Institutional support: RVO:61388963 Keywords : asexual queen succession * breeding system * life history * parthenogenesis * Silvestritermes minutus * termites Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 6.086, year: 2016

  1. Evolutionary history of asexual hybrid loaches (Cobitis: Teleostei) inferred from phylogenetic analysis of mitochondrial DNA variation

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel; Kotlík, Petr; Ráb, Petr

    2003-01-01

    Roč. 16, - (2003), s. 1280-1287 ISSN 1010-061X R&D Projects: GA AV ČR KSK6005114; GA ČR GA206/00/0668; GA ČR GA206/01/0989; GA AV ČR IBS5045111 Institutional research plan: CEZ:AV0Z5045916 Keywords : asexual vertebrates * Cobitis * maternal ancestry Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.010, year: 2003

  2. Will sex selection reduce fertility?

    Science.gov (United States)

    Leung, S F

    1994-01-01

    Population control is one of the primary policies applied against poverty in many low income countries. The widespread prevalence of son preference in some countries such as China and India, however, works against any reduction of fertility. This is so because parents often continue to have children until they obtain the number of sons which they desire. The bias against girls has also led to higher abortion and mortality rates of female children. It is frequently argued that if sex selection methods are made available to parents so that they can control the gender of their children, population growth would be lowered and women's welfare improved. The author investigates both theoretically and numerically the impact of sex selection on fertility. A static quantity-quality model of fertility is used to compare fertility choices when parents cannot choose the gender of children versus a situation in which parents can choose gender. Empirical data are drawn from the 1976 Malaysian Family Life Survey. Analysis found that whether sex selection reduces fertility depends upon the second and third derivatives of the utility function and the child expenditure function. A numerical dynamic analysis is also presented. The simulation shows, using empirical dynamic models of fertility and the Monte Carlo integration technique, that sex selection on the firstborn child among the Chinese in Malaysia could reduce fertility by about 3%.

  3. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana.

    Science.gov (United States)

    Park, Yong-Soon; Park, Kyungseok; Kloepper, Joseph W; Ryu, Choong-Min

    2015-09-01

    Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR) stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  4. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana

    Directory of Open Access Journals (Sweden)

    Yong-Soon Park

    2015-09-01

    Full Text Available Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  5. Evidence of parasexual activity in "asexual amoebae" Cochliopodium spp. (Amoebozoa): extensive cellular and nuclear fusion.

    Science.gov (United States)

    Tekle, Yonas I; Anderson, O Roger; Lecky, Ariel F

    2014-09-01

    The majority of microbial eukaryotes have long been considered asexual, though new evidence indicates sex, or sexual-like (parasexual) behaviors that deviate from the usual union of two gametes, among other variant aspects. Over a dozen amoebozoans are implicated to have sexual stages. However, the exact mechanism by which sex occurs in these lineages remains elusive. This is mainly due to the diverse quality and cryptic nature of their life cycle. In this study we present evidence of some previously unreported aspects of the life cycle of an amoeba, Cochliopodium, that undergoes unusual intraspecific interactions using light microscopy and immunocytochemistry. Similar to other amoebozoans, Cochliopodium, is considered asexual with no published reports of sex or parasexuality. We also investigated environmental conditions that govern the observed intraspecific interactions. Both light microscopic and immunocytochemistry evidence demonstrates Cochliopodium undergoes cellular fusion (plasmogamy) and nuclear fusion (karyogamy). Large plasmodia eventually undergo karyogamy and contain large fused, polyploid, nuclei. These are observed to fragment, subsequently, by karyotomy (nuclear fission) and cytoplasmic fission to yield uninucleated amoebae. This process could lead to a non-meiotic, parasexual exchange of chromosomes in Cochliopodium. These findings strongly suggest that Cochliopodium is involved in parasexual activity and should no longer be considered strictly asexual. Copyright © 2014 Elsevier GmbH. All rights reserved.

  6. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Doctor Information for Patients Many adult survivors of childhood cancer feel fertility preservation and the ability to ... after chemotherapy in male and female survivors of childhood cancer treated between 1970 and 1999: a report ...

  7. Fertility and age

    Directory of Open Access Journals (Sweden)

    Korula George

    2010-01-01

    Full Text Available The changing social scenario together with economic growth and an increase in job opportunities has to a great extent reduced gender inequality and has resulted in more and more older women seeking help from infertility clinics. Fertility and aging have always been closely linked and the age of the female partner remains the single most important factor in predicting success with treatment. Although tests for the ovarian reserve are an important informative tool and are helpful in selecting treatment options, they are poor predictors of the outcome.

  8. The first multi-gene phylogeny of the Macrostomorpha sheds light on the evolution of sexual and asexual reproduction in basal Platyhelminthes.

    Science.gov (United States)

    Janssen, Toon; Vizoso, Dita B; Schulte, Gregor; Littlewood, D Timothy J; Waeschenbach, Andrea; Schärer, Lukas

    2015-11-01

    The Macrostomorpha-an early branching and species-rich clade of free-living flatworms-is attracting interest because it contains Macrostomum lignano, a versatile model organism increasingly used in evolutionary, developmental, and molecular biology. We elucidate the macrostomorphan molecular phylogeny inferred from both nuclear (18S and 28S rDNA) and mitochondrial (16S rDNA and COI) marker genes from 40 representatives. Although our phylogeny does not recover the Macrostomorpha as a statistically supported monophyletic grouping, it (i) confirms many taxa previously proposed based on morphological evidence, (ii) permits the first placement of many families and genera, and (iii) reveals a number of unexpected placements. Specifically, Myozona and Bradynectes are outside the three classic families (Macrostomidae, Microstomidae and Dolichomacrostomidae) and the asexually fissioning Myomacrostomum belongs to a new subfamily, the Myozonariinae nov. subfam. (Dolichomacrostomidae), rather than diverging early. While this represents the first evidence for asexuality among the Dolichomacrostomidae, we show that fissioning also occurs in another Myozonariinae, Myozonaria fissipara nov. sp. Together with the placement of the (also fissioning) Microstomidae, namely as the sister taxon of Dolichomacrostomidae, this suggests that fissioning is not basal within the Macrostomorpha, but rather restricted to the new taxon Dolichomicrostomida (Dolichomacrostomidae+Microstomidae). Furthermore, our phylogeny allows new insights into the evolution of the reproductive system, as ancestral state reconstructions reveal convergent evolution of gonads, and male and female genitalia. Finally, the convergent evolution of sperm storage organs in the female genitalia appears to be linked to the widespread occurrence of hypodermic insemination among the Macrostomorpha. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Slow fertilization of stickleback eggs: the result of sexual conflict?

    Directory of Open Access Journals (Sweden)

    Frommen Joachim G

    2006-05-01

    Full Text Available Abstract Background The fertilization success in sperm competition in externally fertilizing fish depends on number and quality of sperm. The time delay between sequential ejaculations may further influence the outcome of sperm competition. Such a time interval can load the raffle over fertilization if fertilization takes place very fast. Short fertilization times are generally assumed for externally fertilizing fish such as the three-spined stickleback (Gasterosteus aculeatus. In this pair-spawning fish, territorial males often try to steal fertilizations in nests of neighbouring males. This sneaking behaviour causes sperm competition. Sneakers will only get a share of paternity when eggs are not fertilized immediately after sperm release. Contrary to males, females may be interested in multiple paternity of their clutch of eggs. There thus may be a sexual conflict over the speed of fertilization. Results In this study we used two different in vitro fertilization experiments to assess how fast eggs are fertilized in sticklebacks. We show that complete fertilization takes more than 5 min which is atypically long for externally fertilizing fishes. Conclusion This result suggests that the time difference does not imply high costs to the second stickleback male to ejaculate. Slow fertilization (and concomitant prolonged longevity of sperm may be the result of sexual conflict in which females aimed at complete fertilization and/or multiple paternity.

  10. Fertility in female survivors of hodgkin's lymphoma.

    OpenAIRE

    Biasoli, I.; Falorio, S.; Luminari, S.; Spector, N.; Federico, M.

    2012-01-01

    Currently, Hodgkin's lymphoma is one of the most curable types of cancer. Patients are often young and so the long-term morbidities of treatment have become of increasing concern. Among these, infertility is one of the most challenging consequences for patients in reproductive age. Premature ovarian failure in premenopausal women is a serious long-term sequel of the toxicity of chemotherapy. The main consequence of this syndrome is infertility, but women also present other symptoms related to...

  11. Fertility in Female Childhood Cancer Survivors

    NARCIS (Netherlands)

    Bruin, de M.; Broeder, den E.; Berg, van den M.H.; Lambalk, C.B.

    2009-01-01

    Advances in childhood cancer treatment over the past decades have significantly improved survival, resulting in a rapidly enlarging group of childhood cancer survivors. There is much concern, however, about the effects of treatment on reproductive potential. In women there is evidence that both

  12. Fertility of female ostriches (Struthio camelus)

    African Journals Online (AJOL)

    Irek Malecki

    Fertilisation rate in ostrich eggs is high because most eggs contain excessive ... The ostrich breeding system is complex and a “breeding unit” can range from a .... commercial ostrich farm in Western Australia and brought to the Field Station at ...

  13. Fertility preservation in Turner syndrome.

    Science.gov (United States)

    Grynberg, Michaël; Bidet, Maud; Benard, Julie; Poulain, Marine; Sonigo, Charlotte; Cédrin-Durnerin, Isabelle; Polak, Michel

    2016-01-01

    Premature ovarian insufficiency is a relatively rare condition that can appear early in life. In a non-negligible number of cases the ovarian dysfunction results from genetic diseases. Turner syndrome (TS), the most common sex chromosome abnormality in females, is associated with an inevitable premature exhaustion of the follicular stockpile. The possible or probable infertility is a major concern for TS patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The severely reduced follicle pool even during prepubertal life represents the major limit for fertility preservation and is the root of numerous questions regarding the competence of gametes or ovarian tissue crybanked. In addition, patients suffering from TS show higher than usual rates of spontaneous abortion, fetal anomaly, and maternal morbidity and mortality, which should be considered at the time of fertility preservation and before reutilization of the cryopreserved gametes. Apart from fulfillment of the desire of becoming genetic parents, TS patients may be potential candidates for egg donation, gestational surrogacy, and adoption. The present review discusses the different options for preserving female fertility in TS and the ethical questions raised by these approaches. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  14. Female age, serum antimüllerian hormone level, and number of oocytes affect the rate and number of euploid blastocysts in in vitro fertilization/intracytoplasmic sperm injection cycles.

    Science.gov (United States)

    La Marca, Antonio; Minasi, Maria Giulia; Sighinolfi, Giovanna; Greco, Pierfrancesco; Argento, Cindy; Grisendi, Valentina; Fiorentino, Francesco; Greco, Ermanno

    2017-11-01

    To study the relative role of female age and ovarian reserve, measured through serum antimüllerian hormone (AMH) in determining the rate and number of euploid blastocysts in in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles. Retrospective analysis of cycles performed in 2014-2015. Tertiary referral IVF center. A total of 578 infertile couples undergoing IVF/ICSI and preimplantation genetic screening (PGS) analysis. All embryos were cultured and biopsied at the blastocyst stage. The method involved whole-genome amplification followed by array comparative genome hybridization. Serum AMH was measured by means of the modified Beckman Coulter AMH Gen II assay. The rate and number of euploid blastocysts and their correlation with ovarian reserve and response to stimulation. The mean (±SD) age of patients was 37.6 ± 4.1 years, and the mean number of blastocysts per patient was 3.1 ± 2. The total number of blastocysts available to the analysis was 1,814, and 36% of them were euploid after PGS. Age and serum AMH were significantly and independently related to the rate of euploid blastocysts available for patients. As an effect of the cohort size, the number of mature oocytes positively affected the total number of euploid blastocysts per patient. A strong positive age-independent relationship between AMH level and the rate of euploid blastocysts was found. This confirms that the measurement of ovarian reserve by means of AMH has high relevance when counseling infertile patients. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  15. The roles of sexual and asexual reproduction in the origin and dissemination of strains causing fungal infectious disease outbreaks.

    Science.gov (United States)

    Ashu, Eta Ebasi; Xu, Jianping

    2015-12-01

    Sexual reproduction commonly refers to the reproductive process in which genomes from two sources are combined into a single cell through mating and then the zygote genomes are partitioned to progeny cells through meiosis. Reproduction in the absence of mating and meiosis is referred to as asexual or clonal reproduction. One major advantage of sexual reproduction is that it generates genetic variation among progeny which may allow for faster adaptation of the population to novel and/or stressful environments. However, adaptation to stressful or new environments can still occur through mutation, in the absence of sex. In this review, we analyzed the relative contributions of sexual and asexual reproduction in the origin and spread of strains causing fungal infectious diseases outbreaks. The necessity of sex and the ability of asexual fungi to initiate outbreaks are discussed. We propose a framework that relates the modes of reproduction to the origin and propagation of fungal disease outbreaks. Our analyses suggest that both sexual and asexual reproduction can play critical roles in the origin of outbreak strains and that the rapid spread of outbreak strains is often accomplished through asexual expansion. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Lineage dynamics and mutation-selection balance in non-adapting asexual populations

    Science.gov (United States)

    Pénisson, Sophie; Sniegowski, Paul D.; Colato, Alexandre; Gerrish, Philip J.

    2013-02-01

    In classical population genetics, mutation-selection balance refers to the equilibrium frequency of a deleterious allele established and maintained under two opposing forces: recurrent mutation, which tends to increase the frequency of the allele; and selection, which tends to decrease its frequency. In a haploid population, if μ denotes the per capita rate of production of the deleterious allele by mutation and s denotes the selective disadvantage of carrying the allele, then the classical mutation-selection balance frequency of the allele is approximated by μ/s. This calculation assumes that lineages carrying the mutant allele in question—the ‘focal allele’—do not accumulate deleterious mutations linked to the focal allele. In principle, indirect selection against the focal allele caused by such additional mutations can decrease the frequency of the focal allele below the classical mutation-selection balance. This effect of indirect selection will be strongest in an asexual population, in which the entire genome is in linkage. Here, we use an approach based on a multitype branching process to investigate this effect, analyzing lineage dynamics under mutation, direct selection, and indirect selection in a non-adapting asexual population. We find that the equilibrium balance between recurrent mutation to the focal allele and the forces of direct and indirect selection against the focal allele is closely approximated by γμ/(s + U) (s = 0 if the focal allele is neutral), where γ ≈ eθθ-(ω+θ)(ω + θ)(Γ(ω + θ) - Γ(ω + θ,θ)), \\theta =U/\\tilde {s}, and \\omega =s/\\tilde {s}; U denotes the genomic deleterious mutation rate and \\tilde {s} denotes the geometric mean selective disadvantage of deleterious mutations elsewhere on the genome. This mutation-selection balance for asexual populations can remain surprisingly invariant over wide ranges of the mutation rate.

  17. Effects of functionally asexual reproduction on quantitative genetic variation in the evening primroses (Oenothera, Onagraceae).

    Science.gov (United States)

    Godfrey, Ryan M; Johnson, Marc T J

    2014-11-01

    It has long been predicted that a loss of sexual reproduction leads to decreased heritable variation within populations and increased differentiation between populations. Despite an abundance of theory, there are few empirical tests of how sex affects genetic variation in phenotypic traits, especially for plants. Here we test whether repeated losses of two critical components of sex (recombination and segregation) in the evening primroses (Oenothera L., Onagraceae) affect quantitative genetic variation within and between populations. We sampled multiple genetic families from 3-5 populations from each of eight Oenothera species, which represented four independent transitions between sexual reproduction and a functionally asexual genetic system called "permanent translocation heterozygosity." We used quantitative genetics methods to partition genetic variation within and between populations for eight plant traits related to growth, leaf physiology, flowering, and resistance to herbivores. Heritability was, on average, 74% higher in sexual Oenothera populations than in functionally asexual populations, with plant growth rate, specific leaf area, and the percentage of leaf water content showing the strongest differences. By contrast, genetic differentiation among populations was 2.8× higher in functionally asexual vs. sexual Oenothera species. This difference was particularly strong for specific leaf area. Sexual populations tended to exhibit higher genetic correlations among traits, but this difference was weakly supported. These results support the prediction that sexual reproduction maintains higher genetic variation within populations, which may facilitate adaptive evolution. We also found partial support for the prediction that a loss of sex leads to greater population differentiation, which may elevate speciation rates. © 2014 Botanical Society of America, Inc.

  18. Fertility Clinic Success Rates

    Science.gov (United States)

    ... Defects ART and Autism 2013 Assisted Reproductive Technology Fertility Clinic Success Rates Report Recommend on Facebook Tweet ... Additional Information About ART in the United States. Fertility Clinic Tables Introduction to Fertility Clinic Tables [PDF - ...

  19. Fertility and Population Policy

    OpenAIRE

    Ouedraogo, Abdoulaye; Tosun, Mehmet S.; Yang, Jingjing

    2018-01-01

    There have been significant changes in both the fertility rates and fertility perception since 1970s. In this paper, we examine the relationship between government policies towards fertility and the fertility trends. Total fertility rate, defined as the number of children per woman, is used as the main fertility trend variable. We use panel data from the United Nations World Population Policies database, and the World Bank World Development Indicators for the period 1976 through 2013. We find...

  20. Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011–12

    OpenAIRE

    Rajesh Kumar; Vishal Dogra; Khushbu Rani; Kanti Sahu

    2017-01-01

    Background: District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Objective: Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Material and Methods: Data from Annual Health Survey (2011-12) was analysed using STATA and R software packages. Multiple linear regression models...

  1. Fertility preservation in young cancer patients

    Directory of Open Access Journals (Sweden)

    Ariel Revel

    2010-01-01

    Full Text Available As a result of advances in treatment, almost 80% of children and adolescents who receive a diagnosis of cancer become long-term survivors. The increased survival rate of children and adolescents with cancer has resulted in a major interest in the long-term effects of cancer treatment on the possibility for future fertility. Currently established methods for the preservation of fertility are available only for pubertal males and females. Pubertal male cancer patients should be encouraged to freeze numerous sperm samples even when sperm count and motility are poor. In these cases, intracytoplasmic sperm injection is a powerful technique compared with intrauterine insemination since thawed sperm samples with poor parameters can produce relatively high fertilization rates resulting in normal pregnancies and deliveries. Married pubertal women should be proposed ovulation induction, follicular aspiration, and fertilization with husband sperm. Single women could benefit from vitrification of oocytes. This requires a delay of about 3 weeks in the commencement of chemotherapy to enable follicular growth. Fertility preservation for prepubertal patients is more of a problem. Young girls could be offered cryopreservation of gametes in the gonadal tissue. Cryopreservation of testicular tissue was suggested for fertility preservation for young boys, but this method is totally experimental and not currently offered. Discussing future fertility is part of the consultation of young female and male patients facing potentially gonadotoxic cancer therapy. It is the role of reproductive specialists to create various options in their laboratory to preserve fertility potential of cancer patients.

  2. Lycosides, Unusual Carotenoid-Derived Terpenoid Glycosides from a Vegetable Juice, Inhibit Asexual Reproduction of the Plant Pathogen Phytophthora.

    Science.gov (United States)

    Iwai, Rika; Han, Chunguang; Govindam, Sudhakar V S; Ojika, Makoto

    2018-01-10

    Vegetable juices, typical culture media for the plant pathogen Phytophthora, effectively induce its asexual reproduction (zoosporangia formation). However, some chromatographic fractions from a vegetable juice were found to inhibit asexual reproduction. Bioassay-guided chromatographic steps led to the isolation of four novel compounds, named lycosides A-D, 1-4, that could be metabolic products from a carotenoid. They showed 50% inhibitory activity against the asexual reproduction of P. capsici at 2.1-7.6 μM. The structure-activity relationship and the universality of the inhibitory activity within the Phytophthora genus were also investigated. In addition, the quantitative analysis of lycosides in fresh vegetables and vegetable juices revealed that tomato is the source of these active substances. These food-derived chemicals could help provide safe agents to control the outbreak of the agricultural pest Phytophthora in fields.

  3. Widespread occurrence of lysine methylation in Plasmodium falciparum proteins at asexual blood stages.

    Science.gov (United States)

    Kaur, Inderjeet; Zeeshan, Mohammad; Saini, Ekta; Kaushik, Abhinav; Mohmmed, Asif; Gupta, Dinesh; Malhotra, Pawan

    2016-10-20

    Post-transcriptional and post-translational modifications play a major role in Plasmodium life cycle regulation. Lysine methylation of histone proteins is well documented in several organisms, however in recent years lysine methylation of proteins outside histone code is emerging out as an important post-translational modification (PTM). In the present study we have performed global analysis of lysine methylation of proteins in asexual blood stages of Plasmodium falciparum development. We immunoprecipitated stage specific Plasmodium lysates using anti-methyl lysine specific antibodies that immunostained the asexual blood stage parasites. Using liquid chromatography and tandem mass spectrometry analysis, 570 lysine methylated proteins at three different blood stages were identified. Analysis of the peptide sequences identified 605 methylated sites within 422 proteins. Functional classification of the methylated proteins revealed that the proteins are mainly involved in nucleotide metabolic processes, chromatin organization, transport, homeostatic processes and protein folding. The motif analysis of the methylated lysine peptides reveals novel motifs. Many of the identified lysine methylated proteins are also interacting partners/substrates of PfSET domain proteins as revealed by STRING database analysis. Our findings suggest that the protein methylation at lysine residues is widespread in Plasmodium and plays an important regulatory role in diverse set of the parasite pathways.

  4. Characterization of leaf area of Agave fourcroydes Lem. plants obtained from asexual propagation

    Directory of Open Access Journals (Sweden)

    Maryla Sosa del Castillo

    2014-01-01

    Full Text Available The henequen (Agave fourcroydes Lem. is a crop of great economic importance. This study was aimed to characterize the leaf surface of henequen plants variety `Sac Ki' obtained by asexual propagation methods. In vitro plants, shoots of bulbils of in vitro plants, shoots of rhizomes of in vitro plants, shoots of bulbils of field plants and shoots of field rhizomes were used. At 7 and 15 months after planting in the nursery, the epidermis was characterized through the stomatal index and stomatal density. Moreover, the conductor vessels and fiber bundles in leaf mesophyll, were characterized. It was found that the leaf surface of henequen plants variety `Sac Ki' obtained by different methods of asexual propagation showed similar anatomical structures. However, it was observed that in vitro plants were different from the rest in terms of stomatal index and stomatal density in both time points. It was suggesting a accommodate response to environmental conditions. Key words: stomatic density, stomatic index, in vitro plants

  5. Memory and obesity affect the population dynamics of asexual freshwater planarians

    International Nuclear Information System (INIS)

    Dunkel, Jörn; Talbot, Jared; Schötz, Eva-Maria

    2011-01-01

    Asexual reproduction in multicellular organisms is a complex biophysical process that is not yet well understood quantitatively. Here, we report a detailed population study for the asexual freshwater planarian Schmidtea mediterranea, which can reproduce via transverse fission due to a large stem cell contingent. Our long-term observations of isolated non-interacting planarian populations reveal that the characteristic fission waiting time distributions for head and tail fragments differ significantly from each other. The stochastic fission dynamics of tail fragments exhibits non-negligible memory effects, implying that an accurate mathematical description of future data should be based on non-Markovian tree models. By comparing the effective growth of non-interacting planarian populations with those of self-interacting populations, we are able to quantify the influence of interactions between flatworms and physical conditions on the population growth. A surprising result is the non-monotonic relationship between effective population growth rate and nutrient supply: planarians exhibit a tendency to become 'obese' if the feeding frequency exceeds a critical level, resulting in a decreased reproduction activity. This suggests that these flatworms, which possess many genes homologous to those of humans, could become a new model system for studying dietary effects on reproduction and regeneration in multicellular organisms

  6. [Nutrition and fertility].

    Science.gov (United States)

    Szostak-Węgierek, Dorota

    2011-01-01

    There is a growing body of evidence that nutritional habits may have a significant effect on both male and female fertility. Maintenance of normal body mass may be effective in the prevention of infertility resulting from ovulatory disorders. Underweight and, to a larger degree, overweight and/or obesity, are related to the enhanced risk of infertility. Insulin resistance is an important pathogenic mechanism that may impair ovulation. Adequate intake of monounsaturated fatty acids, derived mainly from vegetable fats, as well as avoidance of trans isomers of unsaturated fatty acids which are present in industrially produced cakes and sweets, crisps, fast-foods, powdered soups and hard margarines, may be effective in the prevention of infertility in females. Choice of plant rather than animal sources of proteins, decrease in glycemic load of the diet, use of dietary supplements containing iron and folic acid, could also be beneficial. Avoidance of vitamin B12 deficiency and its supplementation seem to be important in the prevention of early miscarriages. Sufficient intake of antioxidants also promotes female reproductive functions. Free radical processes play an important role in the development of male factor infertility. It was shown that proper intake or supplementation with antioxidants may be effective in its prevention and treatment. Such nutrients as zinc, selenium and folic acid act beneficially on sperm quality. A well-balanced diet seems to play an important role in the prevention of infertility in both sexes.

  7. CONTRIBUTIONS OF SEXUAL AND ASEXUAL REPRODUCTION TO POPULATION STRUCTURE IN THE CLONAL SOFT CORAL, ALCYONIUM RUDYI.

    Science.gov (United States)

    McFadden, Catherine S

    1997-02-01

    Numerous studies of population structure in sessile clonal marine invertebrates have demonstrated low genotypic diversity and nonequilibrium genotype frequencies within local populations that are monopolized by relatively few, highly replicated genets. All of the species studied to date produce planktonic sexual propagules capable of dispersing long distances; despite local genotypic disequilibria, populations are often panmictic over large geographic areas. The population structure paradigm these species represent may not be typical of the majority of clonal invertebrate groups, however, which are believed to produce highly philopatric sexual propagules. I used allozyme variation to examine the population structure of the temperate soft coral, Alcyonium rudyi, a typical clonal species whose sexually produced larvae and asexually produced ramets both have very low dispersal capabilities. Like other clonal plants and invertebrates, the local population dynamics of A. rudyi are dominated by asexual reproduction, and recruitment of new sexually produced genets occurs infrequently. As expected from its philopatric larval stage, estimates of genetic differentiation among populations of A. rudyi were highly significant at all spatial scales examined (mean θ = 0.300 among 20 populations spanning a 1100-km range), suggesting that genetic exchange seldom occurs among populations separated by as little as a few hundred meters. Mapping of multilocus allozyme genotypes within a dense aggregation of A. rudyi ramets confirmed that dispersal of asexual propagules is also very limited: members of the same genet usually remain within invertebrates, populations of A. rudyi do not appear to be dominated by a few widespread genets: estimates of genotypic diversity (G o ) within 20 geographically distinct populations did not differ from expectations for outcrossing, sexual populations. Despite theoretical suggestions that philopatric dispersal combined with typically small effective

  8. Fertility trends in Singapore.

    Science.gov (United States)

    Singh, K; Viegas, O; Ratnam, S S

    1988-10-01

    In 1966, the Singapore National Family Planning and Population Program established the goal of reaching replacement fertility by 1990 and zero population growth by the year 2030. To achieve this goal, the government relied on a series of incentives and disincentives to discourage births above the 3rd birth order, including tax relief for the 1st 3 children only, paid medical leave for women undergoing sterilization after the 3rd or subsequent birth, monetary stipends in some cases where the mother is sterilized after the 1st or 2nd birth, and increasing accouchement charges for increasing birth orders. Also important to demographic planning were liberalization of Singapore's abortion legislation and more aggressive promotion of contraception. As a result of these efforts, Singapore's crude birth rate has declined from 29.5/1000 population in 1965 to 16.6/1000 in 1985. Also observed have been dramatic declines in infant mortality in this same period, from 26.2/1000 live births to 9.3/1000, and in maternal mortality, from 52/100,000 live births to 10/100,000. In 1985, 42% of total births were to women in the 25-29-year age group. The numbers of 4th and later births fell by 90% between 1966 and 1985. The total fertility rate has declined from 4.6/woman in 1965 to 3.1 in 1970 to 1.6 in 1986. Below replacement level fertility was achieved in 1975, in part because of government policy but also as a result of cultural and socioeconomic factors such as increasing female labor force participation rates, a break-up of the extended family system, a rise in the age at 1st marriage, and rises in educational attainment. The drop in fertility was contributed mainly by the higher socioeconomic class, more affluent, and educated Singaporeans. Thus, in 1981, the government introduced certain pronatalist policies and incentives to encourage better educated women to produce more children, e.g., tax relief and the elimination of monetary incentives to sterilization acceptors above a

  9. Protein Kinase A subunits of the ascomycete pathogen Mycosphaerella graminicola regulate asexual fructification, filamentation, melanization and osmosensing

    NARCIS (Netherlands)

    Mehrabi, R.; Kema, G.H.J.

    2006-01-01

    As in many fungi, asexual reproduction of Mycosphaerella graminicola in planta is a complex process that requires proper differentiation of the infectious hyphae in the substomatal cavities of foliar tissue before pycnidia with conidia can be formed. In this study, we have investigated the role of

  10. Asexual propagation in the coral reef macroalga Halimeda (Chlorophyta, Bryopsidales) : production, dispersal and attachment of small fragments

    NARCIS (Netherlands)

    Walters, LJ; Coyer, JA; Hunter, CL; Beach, KS; Vroom, PS

    2002-01-01

    Siphonous, green macroalgae of the genus Halimeda are ubiquitous and ecologically important in tropical and subtropical marine environments. It has been hypothesized that the abundance of Halimeda on coral reefs is in part due to the ability of this genus to propagate asexually via vegetative

  11. Discourses Governing Lesbian, Gay, Bisexual, Transgender, Queer, Intersex, and Asexual Teachers' Disclosure of Sexual Orientation and Gender History

    Science.gov (United States)

    Bower-Phipps, Laura

    2017-01-01

    Significant progress has been made in equal rights for lesbian, gay, bisexual, transgender, queer, intersex, and asexual (LGBTQIA) individuals, yet schools remain institutions where sexual and gender diversity are marginalized and/or silenced. Queer theory, a non-linear theory that disrupts dominant beliefs about gender and sexuality and what…

  12. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex.

    Science.gov (United States)

    Groenewald, Marizeth; Groenewald, Johannes Z; Harrington, Thomas C; Abeln, Edwin C A; Crous, Pedro W

    2006-12-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to determine the full length mating type genes of these species. Primers were developed to amplify and sequence homologous portions of the mating type genes of additional species. Phylogenetic analyses of these sequences revealed little variation among members of the C. apii complex, whereas C. zeae-maydis and C. zeina were found to be dissimilar. The presence of both mating types in approximately even proportions in C. beticola, C. zeae-maydis and C. zeina populations, in contrast to single mating types in C. apii (MAT1) and C. apiicola (MAT2), suggests that a sexual cycle may be active in some of these species.

  13. Transmission of a heterologous clade C Symbiodinium in a model anemone infection system via asexual reproduction

    Directory of Open Access Journals (Sweden)

    Wan-Nan U. Chen

    2016-08-01

    Full Text Available Anemones of genus Exaiptasia are used as model organisms for the study of cnidarian-dinoflagellate (genus Symbiodinium endosymbiosis. However, while most reef-building corals harbor Symbiodinium of clade C, Exaiptasia spp. anemones mainly harbor clade B Symbiodinium (ITS2 type B1 populations. In this study, we reveal for the first time that bleached Exaiptasia pallida anemones can establish a symbiotic relationship with a clade C Symbiodinium (ITS2 type C1. We further found that anemones can transmit the exogenously supplied clade C Symbiodinium cells to their offspring by asexual reproduction (pedal laceration. In order to corroborate the establishment of stable symbiosis, we used microscopic techniques and genetic analyses to examine several generations of anemones, and the results of these endeavors confirmed the sustainability of the system. These findings provide a framework for understanding the differences in infection dynamics between homologous and heterologous dinoflagellate types using a model anemone infection system.

  14. Morphology offers no clues to asexual vs. sexual origin of small Acropora cervicornis (Scleractinia: Acroporidae colonies

    Directory of Open Access Journals (Sweden)

    D. E Williams

    2006-12-01

    Full Text Available Sexual recruitment of the staghorn coral, Acropora cervicornis, is accepted to be very rare. Instead, these branching corals proliferate through fragmentation leading to dense mono-specific and possibly monoclonal stands. For acroporid corals, which have suffered drastic population declines, dominance of asexual reproduction results in low levels of genotypic diversity and limited ability to re-colonize extirpated areas. Small colonies with a single encrusting, symmetrical base, and few incipient branches are frequently presumed to be the result of a settled planula (i.e. sexual reproduction. Here, we show that colonies fitting this description (i.e., presumed sexual recruits can result from asexual fragmentation. Acropora cervicornis colonies (~20 cm diameter were tagged and observed over eighteen months. In several cases, colony offshoots fused with the adjacent substrate forming secondary disc-like attachment points. Following natural fragmentation, these discs of tissue became separated from the original colony, and were observed to heal and give rise to smaller colonies with striking similarity to the expected morphology of a sexual recruit. Thus, presuming a colony is a sexual recruit based on appearance is unreliable and may lead to inflated expectations of genetic diversity among populations. The accurate assessment of recruitment and genetic diversity is crucial to predicting the recovery potential of these imperiled and ecologically irreplaceable reef corals. Rev. Biol. Trop. 54 (Suppl. 3: 145-151. Epub 2007 Jan. 15.Se ha aceptado que el reclutamiento sexual del coral asta de venado, Acropora cervicornis, es muy raro. Por el contrario, estos corales ramificados proliferan a través de fragmentación, generando densas bases monoespecíficas e incluso monoclonales. Para corales acropóridos, los cuales han sufrido disminuciones de población drásticas, la dominancia de reproducción asexual resulta en bajos niveles de diversidad genot

  15. Fixation probability of a nonmutator in a large population of asexual mutators.

    Science.gov (United States)

    Jain, Kavita; James, Ananthu

    2017-11-21

    In an adapted population of mutators in which most mutations are deleterious, a nonmutator that lowers the mutation rate is under indirect selection and can sweep to fixation. Using a multitype branching process, we calculate the fixation probability of a rare nonmutator in a large population of asexual mutators. We show that when beneficial mutations are absent, the fixation probability is a nonmonotonic function of the mutation rate of the mutator: it first increases sublinearly and then decreases exponentially. We also find that beneficial mutations can enhance the fixation probability of a nonmutator. Our analysis is relevant to an understanding of recent experiments in which a reduction in the mutation rates has been observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Global Fertilizer and Manure, Version 1: Nitrogen Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nitrogen Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of nitrogen fertilizer nutrients...

  17. Global Fertilizer and Manure, Version 1: Phosphorus Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phosphorus Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of phosphorus fertilizer nutrients...

  18. A Multinomial Model of Fertility Choice and Offspring Sex-Ratios in India

    OpenAIRE

    Rubiana Chamarbagwala; Martin Ranger

    2007-01-01

    Fertility decline in developing countries may have unexpected demographic consequences. Although lower fertility improves nutrition, health, and human capital investments for surviving children, little is known about the relationship between fertility outcomes and female-male offspring sex-ratios. Particularly in countries with a cultural preference for sons, like India and China, fertility decline may deteriorate the already imbalanced sex-ratios. We use the fertility histories of over 90,00...

  19. Fertilization Mechanisms in Flowering Plants.

    Science.gov (United States)

    Dresselhaus, Thomas; Sprunck, Stefanie; Wessel, Gary M

    2016-02-08

    Compared with the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells, they interact and fuse with two dimorphic female gametes (the egg and the central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here, we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion, as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca(2+) is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes, including mammals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Batch fertility and larval parameters of the jaguar cichlid (Cichlasoma managuense spawned in the laboratory (ESP

    Directory of Open Access Journals (Sweden)

    Jorge Günther Nonell

    2016-03-01

    Full Text Available Batch fertility and larval parameters of 32 spawns of the jaguar guapote (Cichlasoma managuense in the laboratory were analyzed. Batch fertility was positively correlated with the female weight with spawns between about 3000 to 6000 larvae for females between 100 and 500 g wet weight. No significant correlation was found between larval parameters (fresh weight and % dry weight and female weight.

  1. Barriers to Managing Fertility: Findings From the Understanding Fertility Management in Contemporary Australia Facebook Discussion Group.

    Science.gov (United States)

    Holton, Sara; Rowe, Heather; Kirkman, Maggie; Jordan, Lynne; McNamee, Kathleen; Bayly, Christine; McBain, John; Sinnott, Vikki; Fisher, Jane

    2016-02-15

    As part of research investigating the complexities of managing fertility in Australia, public opinions about how Australians manage their fertility were sought from women and men. To identify public opinion about sexual and reproductive health in Australia. To ensure access to a diverse group of people throughout Australia, an online group was advertised and convened on Facebook from October through December 2013. In a closed-group moderated discussion, participants responded to questions about how people in Australia attempt to manage three aspects of fertility: avoiding pregnancy, achieving pregnancy, and difficulties conceiving. Nonidentifiable demographic information was sought; no personal accounts of fertility management were requested. The discussion transcript was analyzed thematically. There were 61 female and 2 male Facebook users aged 18 to 50 years living in Australia participating in the study. Four main themes about fertility management were identified: access, geographical location, knowledge, and cost. Participants reported that young people and people from rural areas face barriers accessing contraception and fertility services. Limited knowledge about sex and reproduction and the cost of fertility services and contraception were also said to impede effective fertility management. Reasons for inequalities in effective fertility management that are amenable to change were identified. Facebook is an effective method for gaining insights into public opinion about sexual and reproductive health.

  2. Barriers to Managing Fertility: Findings From the Understanding Fertility Management in Contemporary Australia Facebook Discussion Group

    Science.gov (United States)

    Rowe, Heather

    2016-01-01

    Background As part of research investigating the complexities of managing fertility in Australia, public opinions about how Australians manage their fertility were sought from women and men. Objective To identify public opinion about sexual and reproductive health in Australia. Methods To ensure access to a diverse group of people throughout Australia, an online group was advertised and convened on Facebook from October through December 2013. In a closed-group moderated discussion, participants responded to questions about how people in Australia attempt to manage three aspects of fertility: avoiding pregnancy, achieving pregnancy, and difficulties conceiving. Nonidentifiable demographic information was sought; no personal accounts of fertility management were requested. The discussion transcript was analyzed thematically. Results There were 61 female and 2 male Facebook users aged 18 to 50 years living in Australia participating in the study. Four main themes about fertility management were identified: access, geographical location, knowledge, and cost. Participants reported that young people and people from rural areas face barriers accessing contraception and fertility services. Limited knowledge about sex and reproduction and the cost of fertility services and contraception were also said to impede effective fertility management. Conclusions Reasons for inequalities in effective fertility management that are amenable to change were identified. Facebook is an effective method for gaining insights into public opinion about sexual and reproductive health. PMID:26878865

  3. A Combined Approach to Heat Stress Effect on Male Fertility in Nasonia vitripennis: From the Physiological Consequences on Spermatogenesis to the Reproductive Adjustment of Females Mated with Stressed Males

    OpenAIRE

    Chirault, Marl?ne; Lucas, Christophe; Goubault, Marl?ne; Chevrier, Claude; Bressac, Christophe; L?cureuil, Charlotte

    2015-01-01

    In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological contro...

  4. Male Fertility Issues

    Science.gov (United States)

    Fertility issues are common in boys and men getting cancer treatment. Fertility preservation options include sperm banking, testicular shielding, testicular sperm extraction (TESE), and testicular tissue freezing. Support and clinical trials are listed.

  5. New histochemical and morphological findings in the female genital tract of Boophilus microplus (Acari, Ixodidae: an attempt toward the elucidation of fertilization in ticks Novas características histoquímicas e morfológicas no trato genital feminino de Boophilus microplus (Acari: Ixodidae: uma tentativa para a elucidação da fertilização nos carrapatos

    Directory of Open Access Journals (Sweden)

    Casimiro García-Fernández

    2005-09-01

    Full Text Available At present not only is the site of fertilization in ticks still unknown but it is also unclear as to how this mystery can be solved. Signs of fertilization can be observed throughout the female genital tract and these can be clues for the elucidation of the unsolved questions relating to ticks fertilization. In Boophilus microplus (Canestrini, 1887 the most important signs are the following: the final eversion of the acrosomal canal in females ready for oviposition; the presence of small tubules, resembling the subplasmalemal process of the spermatozoon between the oviduct cells; budding nuclei throughout the female genital tract; and the two Feulgen and DAPI positive areas in the oocyte at vitelogenesis. These morphological characteristics suggest that fertilization takes place in the internal cylinder which extends from the uterus to the ovary itself.Até o momento, não só o lugar da fertilização em carrapatos é desconhecido, mas também não é claro como este mistério possa ser esclarecido. Sinais de fertilização podem ser observados ao longo do trato genital feminino e estes podem ser pistas para a elucidação das questões relacionadas à fertilização em ácaros. Em Boophilus microplus (Canestrini, 1887, os sinais mais importantes são os seguintes: a eversão final do canal acrossômico em fêmeas prestes à oviposição; a presença de pequenos túbulos assemelhando-se a processos subplasmalêmicos dos espermatozóides entre as células do oviduto; brotamentos nucleares ao longo do trato genital feminino e as duas áreas Feulgen e DAPI positivas nos ovócitos em processo de vitelogênese. Estas características morfológicas sugerem que a fertilização ocorra no cilindro interno, o qual se estende desde o útero até o ovário inclusive.

  6. In-Vitro Fertilization Practice: Awareness and Perceptions ...

    African Journals Online (AJOL)

    BACKGROUND: In-vitro fertilization(IVF) is a procedure that is one of the options in managing infertility. It involves fertilizing the egg from the female with the spermatozoa from the male outside the human body. It is a common practice in the developed world. However it is still a new phenomenon in the developing countries.

  7. Fertilization failure after IVF in 304 couples

    DEFF Research Database (Denmark)

    Krog, Maria; Prior, Maria; Carlsen, Elisabeth

    2015-01-01

    OBJECTIVES: To identify predictors of total fertilization failure (TFF) and thereby optimize the primary allocation of patients with no well-defined male factor to either IVF or intracytoplasmatic sperm injection (ICSI). Further, to evaluate the long-term fertility prognosis of couples experiencing...... TFF. STUDY DESIGN: A retrospective case-control study including 304 couples with TFF and 304 controls with fertilization after IVF during a 10-year period from year 2000-2010. The controls were the patients with minimum one fertilized oocyte just prior to the cases. Multiple logistic regression...... analysis was used to evaluate the predictors of TFF. RESULTS: The multiple regression analysis identified the following independent predictors of TFF: female smoking, adjusted odds ratio (AOR) 1.7 (95% CI 1.1-2.3), non-tubal factor AOR 2.2 (95% CI 1.5-3.4), progressive motile spermatozoa after preparation...

  8. Female self-employment and children

    NARCIS (Netherlands)

    Noseleit, Florian

    2014-01-01

    Several analyses report a positive correlation between fertility and female self-employment; however, scholars disagree about the direction of this relationship. Knowing about the causal relationship is important because the relevant mechanisms and possible implications differ tremendously. This

  9. Couples' fertility decision-making

    Directory of Open Access Journals (Sweden)

    Petra Stein

    2014-06-01

    Full Text Available Background: The decision about whether to start a family within a partnership can be viewed as a result of an interaction process. The influence of each of the partners in a couple differs depending on their individual preferences and intentions towards having children. Both of the partners additionally influence each other's fertility intentions and preferences. Objective: We specify, estimate, and test a model that examines the decision about whether to have a child as a choice that is made jointly by the two partners. The transition to the birth of a (further child is investigated with the explicit consideration of both the female partner and the male partner in the partnership context. Methods: An approach for modelling the interactive influences of the two actors in the decision-making process was proposed. A trivariate distribution consisting of both the female and the male partners' fertility intentions, as well as the joint generative decision, was modelled. A multivariate non-linear probit model was chosen and the problem of identification in estimating the relative effects of the actors was resolved. These parameters were used to assess the relative importance of each of the partners' intentions in the decision. We carried out the analysis with MPLUS. Data from the panel of intimate relationships and family dynamics (pairfam was used to estimate the model. Results: The biographical context of each of the partners in relation to their own as well as to their partner's fertility intentions was found to be of considerable importance. Of the significant individual and partner effects, the male partner was shown to have the greater influence. But the female partner was found to have stronger parameters overall and she ultimately has a veto power in the couple's final decision.

  10. Dynamic formation of asexual diploid and polyploid lineages: multilocus analysis of Cobitis reveals the mechanisms maintaining the diversity of clones.

    Directory of Open Access Journals (Sweden)

    Karel Janko

    Full Text Available Given the hybrid genomic constitutions and increased ploidy of many asexual animals, the identification of processes governing the origin and maintenance of clonal diversity provides useful information about the evolutionary consequences of interspecific hybridization, asexuality and polyploidy. In order to understand the processes driving observed diversity of biotypes and clones in the Cobitis taenia hybrid complex, we performed fine-scale genetic analysis of Central European hybrid zone between two sexual species using microsatellite genotyping and mtDNA sequencing. We found that the hybrid zone is populated by an assemblage of clonally (gynogenetically reproducing di-, tri- and tetraploid hybrid lineages and that successful clones, which are able of spatial expansion, recruit from two ploidy levels, i.e. diploid and triploid. We further compared the distribution of observed estimates of clonal ages to theoretical distributions simulated under various assumptions and showed that new clones are most likely continuously recruited from ancestral populations. This suggests that the clonal diversity is maintained by dynamic equilibrium between origination and extinction of clonal lineages. On the other hand, an interclonal selection is implied by nonrandom spatial distribution of individual clones with respect to the coexisting sexual species. Importantly, there was no evidence for sexually reproducing hybrids or clonally reproducing non-hybrid forms. Together with previous successful laboratory synthesis of clonal Cobitis hybrids, our data thus provide the most compelling evidence that 1 the origin of asexuality is causally linked to interspecific hybridization; 2 successful establishment of clones is not restricted to one specific ploidy level and 3 the initiation of clonality and polyploidy may be dynamic and continuous in asexual complexes.

  11. Dynamic Formation of Asexual Diploid and Polyploid Lineages: Multilocus Analysis of Cobitis Reveals the Mechanisms Maintaining the Diversity of Clones

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel; Kotusz, J.; de Gelas, K.; Šlechtová, Věra; Opoldusová, Zuzana; Drozd, P.; Choleva, Lukáš; Popiolek, M.; Baláž, M.

    2012-01-01

    Roč. 7, č. 9 (2012), s. 1-14 E-ISSN 1932-6203 R&D Projects: GA ČR GA206/09/1298 Grant - others:University of Wroclav(PL) 10/19/S/MP Institutional research plan: CEZ:AV0Z50450515 Keywords : asexual lineages Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.730, year: 2012

  12. Comparative Transcriptomic and Proteomic Analyses Reveal a FluG-Mediated Signaling Pathway Relating to Asexual Sporulation of Antrodia camphorata.

    Science.gov (United States)

    Li, Hua-Xiang; Lu, Zhen-Ming; Zhu, Qing; Gong, Jin-Song; Geng, Yan; Shi, Jin-Song; Xu, Zheng-Hong; Ma, Yan-He

    2017-09-01

    Medicinal mushroom Antrodia camphorata sporulate large numbers of arthroconidia in submerged fermentation, which is rarely reported in basidiomycetous fungi. Nevertheless, the molecular mechanisms underlying this asexual sporulation (conidiation) remain unclear. Here, we used comparative transcriptomic and proteomic approaches to elucidate possible signaling pathway relating to the asexual sporulation of A. camphorata. First, 104 differentially expressed proteins and 2586 differential cDNA sequences during the culture process of A. camphorata were identified by 2DE and RNA-seq, respectively. By applying bioinformatics analysis, a total of 67 genes which might play roles in the sporulation were obtained, and 18 of these genes, including fluG, sfgA, SfaD, flbA, flbB, flbC, flbD, nsdD, brlA, abaA, wetA, ganB, fadA, PkaA, veA, velB, vosA, and stuA might be involved in a potential FluG-mediated signaling pathway. Furthermore, the mRNA expression levels of the 18 genes in the proposed FluG-mediated signaling pathway were analyzed by quantitative real-time PCR. In summary, our study helps elucidate the molecular mechanisms underlying the asexual sporulation of A. camphorata, and provides also useful transcripts and proteome for further bioinformatics study of this valuable medicinal mushroom. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Distribution of Phoxinus eos, Phoxinus neogaeus, and their asexually-reproducing hybrids (Pisces: Cyprinidae in Algonquin Provincial Park, Ontario.

    Directory of Open Access Journals (Sweden)

    Jonathan A Mee

    Full Text Available Hybrid Phoxinus are one of the few asexually reproducing vertebrates species. The distribution of hybrid Phoxinus among lakes in Algonquin Park, Ontario, was evaluated relative to the distribution of parental species and relative to physiochemical lake characteristics. No association between the distribution of hybrids and the distribution of parental species was found, suggesting that the hybrids can successfully coexist with either parental species. In addition, we found no association between hybrid distribution and the physiochemical characteristics of lakes, suggesting that the hybrids are generalists with respect to the ecological niches available in Algonquin Park. There was a difference between the physiochemical characteristics of lakes with and without the parental species P. neogaeus. The lakes containing P. neogaeus were lower elevation than the lakes containing the other parental species, P. eos. The difference in distribution between the parental species may therefore be due to different dispersal abilities, to later arrival following post-glacial dispersal, or to differences in ecology. These results suggest that asexual reproduction is a successful strategy for hybrid Phoxinus in Algonquin Park because these sperm-dependent asexual hybrids are able to survive and persist regardless of which parental species is present, and regardless of the physiochemical characteristics of their habitat.

  14. Asexual sporulation signalling regulates autolysis of Aspergillus nidulans via modulating the chitinase ChiB production.

    Science.gov (United States)

    Pócsi, I; Leiter, E; Kwon, N-J; Shin, K-S; Kwon, G-S; Pusztahelyi, T; Emri, T; Abuknesha, R A; Price, R G; Yu, J-H

    2009-08-01

    Elucidation of the regulation of ChiB production in Aspergillus nidulans. Mutational inactivation of the A. nidulans chiB gene resulted in a nonautolytic phenotype. To better understand the mechanisms controlling both developmental progression and fungal autolysis, we examined a range of autolysis-associated parameters in A. nidulans developmental and/or autolytic mutants. Investigation of disorganization of mycelial pellets, loss of biomass, extra-/intracellular chitinase activities, ChiB production and chiB mRNA levels in various cultures revealed that, in submerged cultures, initialization of autolysis and stationary phase-induced ChiB production are intimately coupled, and that both processes are controlled by the FluG-BrlA asexual sporulation regulatory pathway. ChiB production does not affect the progression of apoptotic cell death in the aging A. nidulans cultures. The endochitinase ChiB plays an important role in autolysis of A. nidulans, and its production is initiated by FluG-BrlA signalling. Despite the fact that apoptosis is an inseparable part of fungal autolysis, its regulation is independent to FluG-initiated sporulation signalling. Deletion of chiB and fluG homologues in industrial filamentous fungal strains may stabilize the hyphal structures in the autolytic phase of growth and limit the release of autolytic hydrolases into the culture medium.

  15. OncoSimulR: genetic simulation with arbitrary epistasis and mutator genes in asexual populations.

    Science.gov (United States)

    Diaz-Uriarte, Ramon

    2017-06-15

    OncoSimulR implements forward-time genetic simulations of biallelic loci in asexual populations with special focus on cancer progression. Fitness can be defined as an arbitrary function of genetic interactions between multiple genes or modules of genes, including epistasis, restrictions in the order of accumulation of mutations, and order effects. Mutation rates can differ among genes, and can be affected by (anti)mutator genes. Also available are sampling from simulations (including single-cell sampling), plotting the genealogical relationships of clones and generating and plotting fitness landscapes. Implemented in R and C ++, freely available from BioConductor for Linux, Mac and Windows under the GNU GPL license. Version 2.5.9 or higher available from: http://www.bioconductor.org/packages/devel/bioc/html/OncoSimulR.html . GitHub repository at: https://github.com/rdiaz02/OncoSimul. ramon.diaz@iib.uam.es. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

  16. Boxer crabs induce asexual reproduction of their associated sea anemones by splitting and intraspecific theft

    Directory of Open Access Journals (Sweden)

    Yisrael Schnytzer

    2017-01-01

    Full Text Available Crabs of the genus Lybia have the remarkable habit of holding a sea anemone in each of their claws. This partnership appears to be obligate, at least on the part of the crab. The present study focuses on Lybia leptochelis from the Red Sea holding anemones of the genus Alicia (family Aliciidae. These anemones have not been found free living, only in association with L. leptochelis. In an attempt to understand how the crabs acquire them, we conducted a series of behavioral experiments and molecular analyses. Laboratory observations showed that the removal of one anemone from a crab induces a “splitting” behavior, whereby the crab tears the remaining anemone into two similar parts, resulting in a complete anemone in each claw after regeneration. Furthermore, when two crabs, one holding anemones and one lacking them, are confronted, the crabs fight, almost always leading to the “theft” of a complete anemone or anemone fragment by the crab without them. Following this, crabs “split” their lone anemone into two. Individuals of Alicia sp. removed from freshly collected L. leptochelis were used for DNA analysis. By employing AFLP (Fluorescence Amplified Fragments Length Polymorphism it was shown that each pair of anemones from a given crab is genetically identical. Furthermore, there is genetic identity between most pairs of anemone held by different crabs, with the others showing slight genetic differences. This is a unique case in which one animal induces asexual reproduction of another, consequently also affecting its genetic diversity.

  17. Implementation strategy for achieving replacement level fertility.

    Science.gov (United States)

    1993-01-01

    The recommendation of the Bali Declaration on Population and Sustainable Development at the ESCAP regional conference was to adopt strategies for attaining replacement-level fertility of 2.1 or 2.2 children by 2010. East Asian countries, except Mongolia and the Democratic People's Republic of Korea, and the Southeast Asian countries Singapore and Thailand have already reached replacement-level fertility. Most larger Oceanic countries have also done so. Only South Asian Sri Lanka and southern India have attained replacement level. The following conditions slow or hinder the goal, but they do not provide an "absolute" barrier to fertility decline: social welfare schemes and old age security, son preference, lack of government family planning, poverty, relatively high mortality, low status of women, and education status. Theories of demographic transition have postulated that economic and social development initially brings a decline in mortality, and later brings a decline in fertility; and high fertility was an adaptation to high mortality. Policy gets caught in the lag between mortality and fertility decline. Eventually the cultural motives for high fertility are undercut by social and economic development. Although the generalization that economic growth slows fertility is true for South Asia, the correlation is uneven. Forceful government-sponsored family planning programs in Bangladesh and China may lead the way to strategies for decline in ESCAP region. A Thailand study suggested important factors were fundamental social change, the increased cost of children, cultural acceptance of birth control, a latent demand for fertility control, and government efforts in family planning. ESCAP countries have in common relatively high morality and inadequate public health programs, patriarchal structures, and limited female autonomy, poverty and landlessness, lack of community cohesiveness, and inadequate family planning programs. Weaknesses in programs are attributed to

  18. Mal-Development of the Penis and Loss of Fertility in Male Rats Treated Neonatally with Female Contraceptive 17α-Ethinyl Estradiol: A Dose-Response Study and a Comparative Study with a Known Estrogenic Teratogen Diethylstilbestrol

    Science.gov (United States)

    Mathews, Ensa; Braden, Tim D.; Williams, Carol S.; Williams, John W.; Bolden-Tiller, Olga; Goyal, Hari O.

    2009-01-01

    The objectives of this study were to find a minimal dose of 17α-ethinyl estradiol (EE) that is detrimental to the developing penis and fertility and to compare estrogenic effects between EE and diethylstilbestrol (DES). Neonatal rats received EE at 10 ng (1 μg/kg), 100 ng, 1 μg, or 10 μg per pup on alternate days from postnatal days 1 to 11 (dose-response study) or received EE or DES at 100 ng per pup daily from postnatal days 1 to 6 (comparative study). Effects of EE were dose dependent, with ≥ 100-ng dose inducing significant (p penis was malformed, characterized by underdeveloped os penis and accumulation of fat cells. Fertility was 0% in the ≥ 1-μg groups, in contrast to 60% in the 100-ng group and 100% in the 10-ng and control groups. Animals treated with ≥ 10 ng had significant reductions in the weight of bulbospongious muscle, testis, seminal vesicle, epididymal fat pad, and in epididymal sperm numbers. A comparison of EE and DES effects showed similar reductions in penile weight and length and the weight of bulbospongiosus muscle, testis, seminal vesicle, epididymis, and epididymal fat pad in both adolescent and adult rats. While 5/6 control males sired, only 1/6 in the EE group and 0/6 in the DES group sired. Hence, neonatal exposure to EE at 10 ng (environmentally relevant dose) adversely affects male reproductive organs. A dose ten times higher than this leads to permanently mal-developed penis and infertility. Furthermore, EE and DES exposures show similar level of toxicity to male reproductive organs. PMID:19729556

  19. Kerala reaps low fertility dividends.

    Science.gov (United States)

    1992-01-01

    Unlike much of India, the state of Kerala has promoted the development of human resources, resulting in lower fertility rates. If current UN projections are correct, India will overtake China as the most populous nation in the world by 2025. Within India, however, great differences exist in fertility rates, reflecting the level of commitment from state governments. In India, state governments control much of the policy and spending on health, education, etc. While the state of Kerala has been among the most committed to human resource development in the developing world, India's 5 northern states (Rajasthan, Uttar Pradesh, Madhya Pradesh, Bihar, and Orissa) have been among the least committed. As a result, Kerala's fertility rate has fallen to 2.3 children/women--a rate lower than that of Thailand, China, the formers USSR, or Ireland. Kerala has a contraceptive prevalence rate 3 times the national average and the lowest infant mortality rate in all of India--only 26/1000 live births (infant mortality is 4-5 times higher in the 5 northern states). Only 27% of Kerala's population lives in poverty, compared to 34-49.5% in the northern states. Real incomes and industrialization have been growing faster in Kerala. And industrialization does not appear to have come at the expense of the environment. 2 factors are responsible for Kerala' accomplishments: 1) State government support of human development--the state has invested in health, education, and has conducted a land reform benefiting 3 million landless peasants. 2) The status of women--in Kerala, women are viewed as an asset, not a liability (as in the north). Kerala's female literacy is 66%, compared to 11-21% in the northern states. Kerala also enjoys the highest level of female labor force participation (35%) anywhere in India.

  20. Hidden Genetic Diversity in an Asexually Reproducing Lichen Forming Fungal Group.

    Directory of Open Access Journals (Sweden)

    Ruth Del-Prado

    Full Text Available Asexual species with vegetative propagation of both symbiont partners (soredia in lichens may harbor lower species diversity because they may indeed represent evolutionary dead ends or clones. In this study we aim to critically examine species boundaries in the sorediate lichen forming fungi Parmotrema reticulatum-Parmotrema pseudoreticulatum complex applying coalescent-based approaches and other recently developed DNA-based methods. To this end, we gathered 180 samples from Africa, Asia, Australasia, Europe, North and South America and generated sequences of internal transcribed spacer of nuclear ribosomal DNA (ITS and DNA replication licensing factor MCM7 (MCM7. The dataset was analysed using different approaches such as traditional phylogeny-maximum likelihood and Bayesian-genetic distances, automatic barcode gap discovery and coalescent-based methods-PTP, GMYC, spedeSTEM and *Beast-in order to test congruence among results. Additionally, the divergence times were also estimated to elucidate diversification events. Delimitations inferred from the different analyses are comparable with only minor differences, and following a conservative approach we propose that the sampled specimens of the P. reticulatum-P. pseudoreticulatum complex belong to at least eight distinct species-level lineages. Seven are currently classified under P. reticulatum and one as P. pseudoreticulatum. In this work we discuss one of only few examples of cryptic species that have so far been found in sorediate reproducing lichen forming fungi. Additionally our estimates suggest a recent origin of the species complex-during the Miocene. Consequently, the wide distribution of several of the cryptic species has to be explained by intercontinental long-distance dispersal events.

  1. Asexual propagation of a virulent clone complex in a human and feline outbreak of sporotrichosis.

    Science.gov (United States)

    Teixeira, Marcus de Melo; Rodrigues, Anderson Messias; Tsui, Clement K M; de Almeida, Luiz Gonzaga Paulo; Van Diepeningen, Anne D; van den Ende, Bert Gerrits; Fernandes, Geisa Ferreira; Kano, Rui; Hamelin, Richard C; Lopes-Bezerra, Leila Maria; Vasconcelos, Ana Tereza Ribeiro; de Hoog, Sybren; de Camargo, Zoilo Pires; Felipe, Maria Sueli Soares

    2015-02-01

    Sporotrichosis is one of the most frequent subcutaneous fungal infections in humans and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual as no sexual stage has ever been reported in Sporothrix schenckii, Sporothrix brasiliensis, or Sporothrix globosa. We have identified the mating type (MAT) loci in the S. schenckii (strain 1099-18/ATCC MYA-4821) and S. brasiliensis (strain 5110/ATCC MYA-4823) genomes by using comparative genomic approaches to determine the mating type ratio in these pathogen populations. Our analysis revealed the presence of a MAT1-1 locus in S. schenckii while a MAT1-2 locus was found in S. brasiliensis representing genomic synteny to other Sordariomycetes. Furthermore, the components of the mitogen-activated protein kinase (MAPK)-pheromone pathway, pheromone processing enzymes, and meiotic regulators have also been identified in the two pathogens, suggesting the potential for sexual reproduction. The ratio of MAT1-1 to MAT1-2 was not significantly different from 1:1 for all three Sporothrix species, but the population of S. brasiliensis in the outbreaks originated from a single mating type. We also explored the population genetic structure of these pathogens using sequence data of two loci to improve our knowledge of the pattern of geographic distribution, genetic variation, and virulence phenotypes. Population genetics data showed significant population differentiation and clonality with a low level of haplotype diversity in S. brasiliensis isolates from different regions of sporotrichosis outbreaks in Brazil. In contrast, S. schenckii isolates demonstrated a high degree of genetic variability without significant geographic differentiation, indicating the presence of recombination. This study demonstrated that two species causing the same disease have contrasting reproductive strategies and genetic variability

  2. Mn(II) oxidation by an ascomycete fungus is linked to superoxide production during asexual reproduction.

    Science.gov (United States)

    Hansel, Colleen M; Zeiner, Carolyn A; Santelli, Cara M; Webb, Samuel M

    2012-07-31

    Manganese (Mn) oxides are among the most reactive minerals within the environment, where they control the bioavailability of carbon, nutrients, and numerous metals. Although the ability of microorganisms to oxidize Mn(II) to Mn(III/IV) oxides is scattered throughout the bacterial and fungal domains of life, the mechanism and physiological basis for Mn(II) oxidation remains an enigma. Here, we use a combination of compound-specific chemical assays, microspectroscopy, and electron microscopy to show that a common Ascomycete filamentous fungus, Stilbella aciculosa, oxidizes Mn(II) to Mn oxides by producing extracellular superoxide during cell differentiation. The reactive Mn oxide phase birnessite and the reactive oxygen species superoxide and hydrogen peroxide are colocalized at the base of asexual reproductive structures. Mn oxide formation is not observed in the presence of superoxide scavengers (e.g., Cu) and inhibitors of NADPH oxidases (e.g., diphenylene iodonium chloride), enzymes responsible for superoxide production and cell differentiation in fungi. Considering the recent identification of Mn(II) oxidation by NADH oxidase-based superoxide production by a common marine bacterium (Roseobacter sp.), these results introduce a surprising homology between some prokaryotic and eukaryotic organisms in the mechanisms responsible for Mn(II) oxidation, where oxidation appears to be a side reaction of extracellular superoxide production. Given the versatility of superoxide as a redox reactant and the widespread ability of fungi to produce superoxide, this microbial extracellular superoxide production may play a central role in the cycling and bioavailability of metals (e.g., Hg, Fe, Mn) and carbon in natural systems.

  3. The cytosolic glyoxalases of Plasmodium falciparum are dispensable during asexual blood-stage development

    Directory of Open Access Journals (Sweden)

    Cletus A. Wezena

    2017-11-01

    Full Text Available The enzymes glyoxalase 1 and 2 (Glo1 and Glo2 are found in most eukaryotes and catalyze the glutathione-dependent conversion of 2-oxoaldehydes to 2-hydroxycarboxylic acids. Four glyoxalases are encoded in the genome of the malaria parasite Plasmodium falciparum, the cytosolic enzymes PfGlo1 and PfcGlo2, the apicoplast enzyme PftGlo2, and an inactive Glo1-like protein that also carries an apicoplast-targeting sequence. Inhibition or knockout of the Plasmodium glyoxalases was hypothesized to lead to an accumulation of 2-oxoaldehydes and advanced glycation end-products (AGE in the host-parasite unit and to result in parasite death. Here, we generated clonal P. falciparum strain 3D7 knockout lines for PFGLO1 and PFcGLO2 using the CRISPR-Cas9 system. Although 3D7Δglo1 knockout clones had an increased susceptibility to external glyoxal, all 3D7Δglo1 and 3D7Δcglo2 knockout lines were viable and showed no significant growth phenotype under standard growth conditions. Furthermore, the lack of PfcGlo2, but not PfGlo1, increased gametocyte commitment in the knockout lines. In summary, PfGlo1 and PfcGlo2 are dispensable during asexual blood-stage development while the loss of PfcGlo2 may induce the formation of transmissible gametocytes. These combined data show that PfGlo1 and PfcGlo2 are most likely not suited as targets for selective drug development.

  4. Dieback Disease Predictive Model for Sexually and Asexually Propagated Dalbergia Sissoo (Shisham)

    International Nuclear Information System (INIS)

    Ahmad, I.; Siddiqui, M. T.; Nawaz, M. F.; Asif, M.; Atiq, M.; Gul, S.

    2016-01-01

    Dieback disease is a potential threat to Dalbergia sissoo (Shisham) which is a multipurpose tree of the Indian subcontinent. Different factors have been found associated with inciting shisham dieback. Fungal pathogens have been recognized as the major causal organism but changing climate is a main threat to forest dieback. Sexually (seedlings) and asexually (cuttings) propagated shisham were inoculated with the different fungi (Fusarium solani, Botryodiplodia theobromae, Curvularia lunata and Ganoderma lucidum). As environmental factors play critical role in the development of the disease, so the present study was designed to observe the impact of rainfall, temperature, relative humidity and wind velocity on the disease and for the management of disease predictive model was developed. A significant negative correlation was observed between disease and relative humidity both for seedlings (r = - 0.97) and cuttings (r = -0.487), respectively while maximum temperature expressed significant positive correlation with seedlings and cuttings with coefficient of correlation r = 0.734 and r = 0.629, respectively. Path analysis expressed that with one unit increase in rainfall the disease would rise by 7.58 and 15.04 and for maximum temperature it was 2.47 and 5.27 units in seedlings and cuttings, respectively. Multiple regression analysis showed that coefficient of determination (R/sup 2/) value was 0.62 and 0.48 for cuttings and seedlings, respectively. Normed fit index (NFI) and comparative fit index (CFI) values indicate that model is quite a good fit. Similarly comparison of observed and predicted data also validated the model for forecasting the disease. (author)

  5. Presence and Functionality of Mating Type Genes in the Supposedly Asexual Filamentous Fungus Aspergillus oryzae

    Science.gov (United States)

    Wada, Ryuta; Maruyama, Jun-ichi; Yamaguchi, Haruka; Yamamoto, Nanase; Wagu, Yutaka; Paoletti, Mathieu; Archer, David B.; Dyer, Paul S.

    2012-01-01

    The potential for sexual reproduction in Aspergillus oryzae was assessed by investigating the presence and functionality of MAT genes. Previous genome studies had identified a MAT1-1 gene in the reference strain RIB40. We now report the existence of a complementary MAT1-2 gene and the sequencing of an idiomorphic region from A. oryzae strain AO6. This allowed the development of a PCR diagnostic assay, which detected isolates of the MAT1-1 and MAT1-2 genotypes among 180 strains assayed, including industrial tane-koji isolates. Strains used for sake and miso production showed a near-1:1 ratio of the MAT1-1 and MAT1-2 mating types, whereas strains used for soy sauce production showed a significant bias toward the MAT1-2 mating type. MAT1-1 and MAT1-2 isogenic strains were then created by genetic manipulation of the resident idiomorph, and gene expression was compared by DNA microarray and quantitative real-time PCR (qRT-PCR) methodologies under conditions in which MAT genes were expressed. Thirty-three genes were found to be upregulated more than 10-fold in either the MAT1-1 host strain or the MAT1-2 gene replacement strain relative to each other, showing that both the MAT1-1 and MAT1-2 genes functionally regulate gene expression in A. oryzae in a mating type-dependent manner, the first such report for a supposedly asexual fungus. MAT1-1 expression specifically upregulated an α-pheromone precursor gene, but the functions of most of the genes affected were unknown. The results are consistent with a heterothallic breeding system in A. oryzae, and prospects for the discovery of a sexual cycle are discussed. PMID:22327593

  6. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei).

    Science.gov (United States)

    Majtánová, Zuzana; Choleva, Lukáš; Symonová, Radka; Ráb, Petr; Kotusz, Jan; Pekárik, Ladislav; Janko, Karel

    2016-01-01

    Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis). We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA). Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  7. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei.

    Directory of Open Access Journals (Sweden)

    Zuzana Majtánová

    Full Text Available Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis. We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA. Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  8. [Fertility transition in Peru].

    Science.gov (United States)

    Ferrando, D; Aramburu, C E

    1992-12-01

    Data from national censuses and sample surveys are the basis for this examintion of differential fertility and the fertility transition in Peru. Changes in the level and structure of fertility in the 3 major geographic regions are compared, and the role of contraceptive usage and nuptiality changes in the fertility decline are analyzed. Peru's total fertility rate was estimated at 6.85 in 1965 and has since declined to 6.56 in 1965-70, 6.00 in 1970-75, 5.30 in 1975-80, 4.65 in 1980-85, and 4.00 in 1985-90. The fertility decline varied in intensity and timing in the geographic regions. A clear fertility decline began among upper and middle income groups in the principal cities in the 1960s, spreading gradually to the urban low income sectors. Not until the late 1970s did the fertility decline spread to the rest of the population, coinciding with the years of severe economic crisis. The urban total fertility rate declined from 6 to 3.77 during 1961-86, but rural fertility increased through 1972 to 8.12, before declining slightly to 7.62 in 1981 and more markedly to 6.65 in 1986. Sociocultural and economic differences between Peru's natural regions are appreciable, and account for the contrasts in fertility trends. The greatest changes occurred in metropolitan Lima, which already had relatively low fertility in 1961. Its total fertility rate declined 44% from 5.6 in 1961 to 3.13 in 1986. Fertility declined by slightly under 40% in the rest of the coast, by almost 25% in the jungle, and by scarcely 14% in the sierra. The total fertility rates in 1961 and 1986, respectively, were 6.38 and 4.13 on the coast, 6.64 and 6.45 in the highlands, and 7.92 and 5.97 in the lowlands. The fertility decline, especially in the lower classes, was a response initially to the process of cultural modernization which in slightly over 2 decades saw a profound transformation of Peru from a rural, Andean, illiterate, and agrarian society to an urban, coastal, literate, and commercial society

  9. Fertility preservation for medical reasons in girls and women: British fertility society policy and practice guideline.

    Science.gov (United States)

    Yasmin, Ephia; Balachandren, Neerujah; Davies, Melanie C; Jones, Georgina L; Lane, Sheila; Mathur, Raj; Webber, Lisa; Anderson, Richard A

    2018-04-01

    Fertility preservation in the female poses several challenges due to the invasive nature of the techniques available to achieve it. The guideline aims to bring together the evidence available for the measures for fertility preservation and their outcome. The guideline addresses fertility preservation for medical reasons and includes both oncological and non-oncological causes. The techniques that the guideline considers are: (i) embryo and oocyte cryopreservation; (ii) ovarian tissue cryopreservation; (iii) GnRH agonist suppression and (iv) ovarian transposition. Although ovarian tissue cryopreservation is still considered experimental, the availability of this technique is gaining momentum as more live births from auto-transplanted tissue are reported. The guideline also highlights use of current treatment modalities for benign and malignant conditions that have a better fertility sparing profile. The guideline recommends a multidisciplinary approach in counselling women and girls about the risk to their fertility and available techniques. The role of psychological support in assisting women and girls with decision-making is highlighted. The guideline also highlights the risks associated with these techniques. Women need to be medically fit to undergo invasive procedures. Fertility preservation techniques are appropriate when treatment has curative intent. Fertility preservation is a subject of on-going research on outcomes of different techniques and at the time of publication, studies are still likely to emerge adding to the available literature.

  10. Low fertilization rates in a pelagic copepod caused by sexual selection?

    DEFF Research Database (Denmark)

    Ceballos, Sara; Sichlau, Mie Hylstofte; Heuschele, Jan

    2014-01-01

    We studied female fertilization status in North Sea summer populations and laboratory cultures of the marine copepod Temora longicornis and found fractions of fertilized females in both field and laboratory populations that were much smaller (<50%) than predicted by a theoretical model that assum...

  11. Protect Your Fertility

    Science.gov (United States)

    ... your teens and early twenties can affect your fertility for years to come. This prevention guide was written by ... loss of testic- ulor size, see your doctor. Fertility is something that you ... approximately 40 percent of infertile couples, the male partner is ...

  12. Fertilization in northern forests

    DEFF Research Database (Denmark)

    Hedwall, Per Ola; Gong, Peichen; Ingerslev, Morten

    2014-01-01

    resources into food, health and industrial products and energy. Fertilization in Sweden and Finland is currently practiced by extensive fertilization regimens where nitrogen fertilizers are applied once, or up to three times, during a rotation period, mainly in mature forest. This type of fertilization...... gives, in most cases, a small and transient effect on the environment as well as a high rate of return to the forest owner with low-economic risk. The increase in biomass production, however, is relatively small and consequently the impact on the processing industry and the bioeconomy is limited. More...... in combination with present management systems and, almost instantly, enhances forest productivity. There may, however, be both economic and environmental constraints to large-scale applications of fertilizers in forest. Here we review the literature concerning biomass production of forests under different...

  13. Mitochondrial functionality in female reproduction

    Directory of Open Access Journals (Sweden)

    Łukasz Gąsior

    2017-01-01

    Full Text Available In most animal species female germ cells are the source of mitochondrial genome for the whole body of individuals. As a source of mitochondrial DNA for future generations the mitochondria in the female germ line undergo dynamic quantitative and qualitative changes. In addition to maintaining the intact template of mitochondrial genome from one generation to another, mitochondrial role in oocytes is much more complex and pleiotropic. The quality of mitochondria determines the ability of meiotic divisions, fertilization ability, and activation after fertilization or sustaining development of a new embryo. The presence of normal number of functional mitochondria is also crucial for proper implantation and pregnancy maintaining. This article addresses issues of mitochondrial role and function in mammalian oocyte and presents new approaches in studies of mitochondrial function in female germ cells.

  14. Mature Oocyte Cryopreservation for Fertility Preservation.

    Science.gov (United States)

    Liang, Tina; Motan, Tarek

    2016-01-01

    In recent decades, advances in cancer treatment have led to a dramatic improvement in long term survival. This has led to an increasing focus on quality of life after surviving cancer treatment, with fertility being an important aspect. Given the known reproductive risks of cancer therapies, there has been a growing interest in the field of fertility preservation (also referred to as oncofertility). Mature oocyte cryopreservation is no longer considered experimental and has become a realistic option for reproductive aged women prior to undergoing cancer treatment. Additionally, as cryopreservation techniques improve, mature oocyte cryopreservation is increasing being marketed to healthy women without cancer wishing to delay child bearing, also termed "social egg freezing". This chapter provides a review of the current technology, use, and outcomes of mature oocyte cryopreservation. It also outlines the ethical debate surrounding social egg freezing and directions for future research in female fertility preservation.

  15. Molecular mechanisms of fertilization: the role of male factor

    Directory of Open Access Journals (Sweden)

    Ewa Maria Kratz

    2011-11-01

    Full Text Available Fertilization, the fusion of male and female gametes, is an incompletely known, multistep, complex process, in which many factors participate. Fertilization is a precisely regulated, species-specific process, but some cellular mechanisms are similar for many mammal species. The studies of mechanisms of male and female gamete production enable understanding of fertilization issues and, as a result, make the analysis of the causes of infertility possible. Male and female infertility is a progressive phenomenon. The development of laboratory medicine enables the analysis of molecular aspects of the reactions between gametes, which may result in better diagnosis of many infertility cases and indicate the direction of therapeutic management. The fertilization process is accompanied by many biochemical reactions, in which glycoproteins present in human ejaculate play a very important role. Glycan structures enable glycoproteins to participate in the interactions between cells, including those between gametes. The analysis of the glycosylation profile and degree of ejaculate glycoproteins not only contributes to deepening the knowledge about mechanisms accompanying the fertilization process, but also may be useful as an additional diagnostic marker of male infertility.The aim of the present review is to approach selected molecular mechanisms occurring in the male genital tract, related to the fertilization process, as well as to analyze their influence on male fertility.

  16. Environmental control of asexual reproduction and somatic growth of Aurelia spp. (Cnidaria, Scyphozoa) polyps from the Adriatic Sea

    OpenAIRE

    Hubot, Nathan; Lucas, Cathy H.; Piraino, Stefano

    2017-01-01

    Polyps of two moon jellyfish species, Aurelia coerulea and A.relicta, from two Adriatic Sea coastal habitats were incubated under multiple combinations of temperature (14, 21 °C), salinity (24, 37 ppt) and food regime (9.3, 18.6, 27.9 μg C ind‾¹ week‾¹) to comparatively assess how these factors may influence major asexual reproduction processes in the two species. Both species exhibited a shared pattern of budding mode (Directly Budded Polyps: DBP; Stolonal Budded Polyps: SBP), with DBP favo...

  17. Phylogeography of herbarium specimens of asexually propagated paper mulberry [Broussonetia papyrifera (L.) L'Hér. ex Vent. (Moraceae)] reveals genetic diversity across the Pacific.

    Science.gov (United States)

    Payacan, Claudia; Moncada, Ximena; Rojas, Gloria; Clarke, Andrew; Chung, Kuo-Fang; Allaby, Robin; Seelenfreund, Daniela; Seelenfreund, Andrea

    2017-09-01

    Paper mulberry or Broussonetia papyrifera (L.) L'Hér. ex Vent. (Moraceae) is a dioecious species native to continental South-east Asia and East Asia, including Taiwan, that was introduced to the Pacific by pre-historic voyagers and transported intentionally and propagated asexually across the full range of Austronesian expansion from Taiwan to East Polynesia. The aim of this study was to gain insight into the dispersal of paper mulberry into Oceania through the genetic analysis of herbaria samples which represent a more complete coverage of the historical geographical range of the species in the Pacific before later introductions and local extinctions occurred. DNA from 47 herbarium specimens of B. papyrifera collected from 1882 to 2006 from different islands of the Pacific was obtained under ancient DNA protocols. Genetic characterization was based on the ribosomal internal transcribed spacer ITS-1 sequence, a sex marker, the chloroplast ndhF-rpl32 intergenic spacer and a set of ten microsatellites developed for B. papyrifera. Microsatellites allowed detection of 15 genotypes in Near and Remote Oceanian samples, in spite of the vegetative propagation of B. papyrifera in the Pacific. These genotypes are structured in two groups separating West and East Polynesia, and place Pitcairn in a pivotal position. We also detected the presence of male plants that carry the Polynesian chloroplast DNA (cpDNA) haplotype, in contrast to findings in contemporary B. papyrifera populations where only female plants bear the Polynesian cpDNA haplotype. For the first time, genetic diversity was detected among paper mulberry accessions from Remote Oceania. A clear separation between West and East Polynesia was found that may be indicative of pulses during its dispersal history. The pattern linking the genotypes within Remote Oceania reflects the importance of central Polynesia as a dispersal hub, in agreement with archaeological evidence. © The Author 2017. Published by Oxford

  18. General aspects of fertility and infertility.

    Science.gov (United States)

    Damario, Mark A

    2014-01-01

    Fertility rates have been declining in most Western nations over the past several decades, although it is not entirely clear if an increased rate of infertility substantially contributes to this. As compared to other species, the reproductive efficiency of humans is relatively low. Factors related to fertility include age, exposure to sexually transmitted diseases, frequency of intercourse, coital timing, as well as diet and lifestyle habits. Infertility is considered a disease due to its major disruption of major organ systems and life functions. An infertility evaluation is recommended after 12 months or more of regular, unprotected intercourse and may be considered after 6 months for those female patients over the age of 35 or with other known abnormalities. A proper infertility evaluation is a comprehensive examination of possibly identifiable infertility factors of both female and male partners, lending itself to the most appropriate and potentially effective treatment.

  19. Men perceive their female partners, and themselves, as more attractive around ovulation

    NARCIS (Netherlands)

    Cobey, Kelly D.; Buunk, Abraham P.; Pollet, Thomas V.; Klipping, Christine; Roberts, S. Craig

    2013-01-01

    The purpose of this study was to test whether men perceive changes in their female partner's attractiveness as a function of her fertility status. We further tested how both male and female self-perception varies in relation to female fertility status. This study benefits from the use of

  20. Polymorphism and methylation patterns in Agave tequilana Weber var. 'Azul' plants propagated asexually by three different methods.

    Science.gov (United States)

    Díaz-Martínez, Miriam; Nava-Cedillo, Alejandro; Guzmán-López, José Alfredo; Escobar-Guzmán, Rocío; Simpson, June

    2012-04-01

    Genetic variation in three forms of asexually propagated Agave tequilana Weber var. 'Azul' plants namely offsets, bulbils and in vitro cultured individuals was studied by AFLP analysis. Low levels of variation were observed between mother plants and offsets and a higher level between mother plant and bulbils. Families obtained from commercial plantations showed lower levels of variation in comparison to families grown as ornamentals. No variation was observed between the original explant and four generations of in vitro cultured plants. Epigenetic variation was also studied by analyzing changes in methylation patterns between mother plants and offspring in each form of asexual reproduction. Offsets and bulbils showed an overall decrease in methylation whereas in vitro cultured plants showed patterns specific to each generation: Generations 1 and 4 showed overall demethylation whereas Generations 2 and 3 showed increased methylation. Analysis of ESTs associated with transposable elements revealed higher proportions of ESTs from Ty1-copia-like, Gypsy and CACTA transposable elements in cDNA libraries obtained from pluripotent tissue suggesting a possible correlation between methylation patterns, expression of transposable element associated genes and somaclonal variation. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  1. Sex in an uncertain world: environmental stochasticity helps restore competitive balance between sexually and asexually reproducing populations.

    Science.gov (United States)

    Park, A W; Vandekerkhove, J; Michalakis, Y

    2014-08-01

    Like many organisms, individuals of the freshwater ostracod species Eucypris virens exhibit either obligate sexual or asexual reproductive modes. Both types of individual routinely co-occur, including in the same temporary freshwater pond (their natural habitat in which they undergo seasonal diapause). Given the well-known two-fold cost of sex, this begs the question of how sexually reproducing individuals are able to coexist with their asexual counterparts in spite of such overwhelming costs. Environmental stochasticity in the form of 'false dawn' inundations (where the first hydration is ephemeral and causes loss of early hatching individuals) may provide an advantage to the sexual subpopulation, which shows greater variation in hatching times following inundation. We explore the potential role of environmental stochasticity in this system using life-history data analysis, climate data, and matrix projection models. In the absence of environmental stochasticity, the population growth rate is significantly lower in sexual subpopulations. Climate data reveal that 'false dawn' inundations are common. Using matrix projection modelling with and without environmental stochasticity, we demonstrate that this phenomenon can restore appreciable balance to the system, in terms of population growth rates. This provides support for the role of environmental stochasticity in helping to explain the maintenance of sex and the occurrence of geographical parthenogenesis. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  2. A Global Survey of ATPase Activity in Plasmodium falciparum Asexual Blood Stages and Gametocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Corrie; Frando, Andrew; Webb-Robertson, Bobbie-Jo; Anderson, Lindsey N.; Fleck, Neil; Flannery, Erika L.; Fishbaugher, Matthew; Murphree, Taylor A.; Hansen, Joshua R.; Smith, Richard D.; Kappe, Stefan H. I.; Wright, Aaron T.; Grundner, Christoph

    2017-10-27

    Effective malaria control and elimination in hyperendemic areas of the world will require treatment of disease-causing Plasmodium falciparum (Pf) blood stage infection but also blocking parasite transmission from humans to mosquito to prevent disease spread. Numerous antimalarial drugs have become ineffective due to parasite drug resistance and many currently used therapies do not kill gametocytes, highly specialized sexual parasite stages with distinct physiology that are necessary for transmission from the human host to the mosquito vector. Further confounding next generation drug development against Pf is the lack of known biochemical activity for most parasite gene products as well as the unknown metabolic needs of non-replicating gametocyte. Here, we take a systematic activity-based proteomics approach to survey the large and druggable ATPase family that is associated with replicating blood stage asexual parasites and transmissible gametocytes. We experimentally confirm existing annotation and predict ATPase function for 38 uncharacterized proteins. ATPase activity broadly changes during the transition from asexual schizonts to gametocytes, indicating altered metabolism and regulatory roles of ATPases specific for each lifecycle stage. By mapping the activity of ATPases associated with gametocytogenesis, we assign biochemical activity to a large number of uncharacterized proteins and identify new candidate transmission blocking targets.

  3. FvSTR1, a striatin orthologue in Fusarium virguliforme, is required for asexual development and virulence.

    Science.gov (United States)

    Islam, Kazi T; Bond, Jason P; Fakhoury, Ahmad M

    2017-08-01

    The soil-borne fungus Fusarium virguliforme causes sudden death syndrome (SDS), one of the most devastating diseases of soybean in North and South America. Despite the importance of SDS, a clear understanding of the fungal pathogenicity factors that affect the development of this disease is still lacking. We have identified FvSTR1, a F. virguliforme gene, which encodes a protein similar to a family of striatin proteins previously reported to regulate signalling pathways, cell differentiation, conidiation, sexual development, and virulence in filamentous fungi. Striatins are multi-domain proteins that serve as scaffolding units in the striatin-interacting phosphatase and kinase (STRIPAK) complex in fungi and animals. To address the function of a striatin homologue in F. virguliforme, FvSTR1 was disrupted and functionally characterized using a gene knock out strategy. The resulting Fvstr1 mutants were largely impaired in conidiation and pigmentation, and displayed defective conidia and conidiophore morphology compared to the wild-type and ectopic transformants. Greenhouse virulence assays revealed that the disruption of FvSTR1 resulted in complete loss of virulence in F. virguliforme. Microtome studies using fluorescence microscopy showed that the Fvstr1 mutants were defective in their ability to colonize the vascular system. The Fvstr1 mutants also showed a reduced transcript level of genes involved in asexual reproduction and in the production of secondary metabolites. These results suggest that FvSTR1 has a critical role in asexual development and virulence in F. virguliforme.

  4. Perchlorate in Fertilizers

    National Research Council Canada - National Science Library

    Eldridge, J. E; Tsui, D. T; Mattie, D. R; Crown, J; Scott, R; Blackman, T

    1999-01-01

    ...) methods for perchlorate analysis in lawn and garden fertilizers. Seven government, private, and commercial laboratories participated in the analysis of 34 aqueous suspensions of the test materials, using similar ion chromatography systems...

  5. Commercial Phosporus Fertilizer Purchased

    Data.gov (United States)

    U.S. Environmental Protection Agency — Amounts of fertilizer P2O5 purchased by states in individual years 2003, 2005, 2007, 2009 and 2011, and the % change in average amounts purchased per year from...

  6. Commercial Nitrogen Fertilizer Purchased

    Data.gov (United States)

    U.S. Environmental Protection Agency — Amounts of fertilizer nitrogen (N) purchased by states in individual years 2003, 2005, 2007, 2009 and 2011, and the % change in average amounts purchased per year...

  7. Cancer and fertility preservation

    DEFF Research Database (Denmark)

    Lambertini, Matteo; Del Mastro, Lucia; Pescio, Maria C

    2016-01-01

    In the last years, thanks to the improvement in the prognosis of cancer patients, a growing attention has been given to the fertility issues. International guidelines on fertility preservation in cancer patients recommend that physicians discuss, as early as possible, with all patients...... of reproductive age their risk of infertility from the disease and/or treatment and their interest in having children after cancer, and help with informed fertility preservation decisions. As recommended by the American Society of Clinical Oncology and the European Society for Medical Oncology, sperm...... data have become available, and several issues in this field are still controversial and should be addressed by both patients and their treating physicians.In April 2015, physicians with expertise in the field of fertility preservation in cancer patients from several European countries were invited...

  8. Queering the fertility clinic.

    Science.gov (United States)

    Mamo, Laura

    2013-06-01

    A sociologist examines contemporary engagements of queer bodies and identities with fertility biomedicine. Drawing on social science, media culture, and the author's own empirical research, three questions frame the analysis: 1. In what ways have queers on the gendered margins moved into the center and become implicated or central users of biomedicine's fertility offerings? 2. In what ways is Fertility Inc. transformed by its own incorporation of various gendered and queered bodies and identities? And 3. What are the biosocial and bioethical implications of expanded queer engagements and possibilities with Fertility Inc.? The author argues that "patient" activism through web 2.0 coupled with a largely unregulated free-market of assisted reproduction has included various queer identities as "parents-in-waiting." Such inclusions raise a set of ethical tensions regarding how to be accountable to the many people implicated in this supply and demand industry.

  9. Sperm preparation for fertilization

    NARCIS (Netherlands)

    Gadella, B.M.

    2014-01-01

    Description This book contains 19 chapters that discuss theoretical and applied andrology for domestic, zoo and wild animals. Topics include semen and its constituents; sperm production and harvest; determinants of sperm morphology; sperm preparation for fertilization; practical aspects of semen

  10. Fertilization in Flowering Plants

    Indian Academy of Sciences (India)

    Ecology and the. Environment ... agents (pollinators), the next step before fertilization is to se- .... the embryo sac are referred to as pollen-pistil interaction and play ..... evolutionary success of flowering plants when compared to other groups of ...

  11. Immunosuppressive drugs and fertility

    OpenAIRE

    Leroy, Clara; Rigot, Jean-Marc; Leroy, Maryse; Decanter, Christine; Le Mapihan, Kristell; Parent, Anne-Sophie; Le Guillou, Anne-Claire; Yakoub-Agha, Ibrahim; Dharancy, Sébastien; Noel, Christian; Vantyghem, Marie-Christine

    2015-01-01

    Immunosuppressive drugs are used in the treatment of inflammatory and autoimmune diseases, as well as in transplantation. Frequently prescribed in young people, these treatments may have deleterious effects on fertility, pregnancy outcomes and the unborn child. This review aims to summarize the main gonadal side effects of immunosuppressants, to detail the effects on fertility and pregnancy of each class of drug, and to provide recommendations on the management of patients who are seen prior ...

  12. Organic Biochar Based Fertilization

    Science.gov (United States)

    Schmidt, Hans-Peter; Pandit, Bishnu Hari; Cornelissen, Gerard; Kammann, Claudia

    2017-04-01

    Biochar produced in cost-efficient flame curtain kilns (Kon-Tiki) was nutrient enriched either with cow urine or with dissolved mineral (NPK) fertilizer to produce biochar-based fertilizers containing between 60-100 kg N, 5-60 kg P2O5 and 60-100 kg K2O, respectively, per ton of biochar. In 21 field trials nutrient-enriched biochars were applied at rates of 0.5 to 2 t ha-1 into the root zone of 13 different annual and perennial crops. Treatments combining biochar, compost and organic or chemical fertilizer were evaluated; control treatments contained the same amounts of nutrients but without biochar. All nutrient-enriched biochar substrates improved yields compared to their respective no-biochar controls. Biochar enriched with dissolved NPK produced on average 20% ± 5.1% (N=4) higher yields than standard NPK fertilization without biochar. Cow urine-enriched biochar blended with compost resulted on average in 123% ± 76.7% (N=13) higher yields compared to the organic farmer practice with cow urine-blended compost and outcompeted NPK-enriched biochar (same nutrient dose) by 103% ± 12.4% (N=4) on average. 21 field trials robustly revealed that low-dosage root zone application of organic biochar-based fertilizers caused substantial yield increases in rather fertile silt loam soils compared to traditional organic fertilization and to mineral NPK- or NPK-biochar fertilization. This can likely be explained by the nutrient carrier effect of biochar causing a slow nutrient release behavior, more balanced nutrient fluxes and reduced nutrient losses especially when liquid organic nutrients are used for the biochar enrichment. The results promise new pathways for optimizing organic farming and improving on-farm nutrient cycling.

  13. High-fertility phenotypes: two outbred mouse models exhibit substantially different molecular and physiological strategies warranting improved fertility.

    Science.gov (United States)

    Langhammer, Martina; Michaelis, Marten; Hoeflich, Andreas; Sobczak, Alexander; Schoen, Jennifer; Weitzel, Joachim M

    2014-01-01

    Animal models are valuable tools in fertility research. Worldwide, there are more than 400 transgenic or knockout mouse models available showing a reproductive phenotype; almost all of them exhibit an infertile or at least subfertile phenotype. By contrast, animal models revealing an improved fertility phenotype are barely described. This article summarizes data on two outbred mouse models exhibiting a 'high-fertility' phenotype. These mouse lines were generated via selection over a time period of more than 40 years and 161 generations. During this selection period, the number of offspring per litter and the total birth weight of the entire litter nearly doubled. Concomitantly with the increased fertility phenotype, several endocrine parameters (e.g. serum testosterone concentrations in male animals), physiological parameters (e.g. body weight, accelerated puberty, and life expectancy), and behavioral parameters (e.g. behavior in an open field and endurance fitness on a treadmill) were altered. We demonstrate that the two independently bred high-fertility mouse lines warranted their improved fertility phenotype using different molecular and physiological strategies. The fertility lines display female- as well as male-specific characteristics. These genetically heterogeneous mouse models provide new insights into molecular and cellular mechanisms that enhance fertility. In view of decreasing fertility in men, these models will therefore be a precious information source for human reproductive medicine. Translated abstract A German translation of abstract is freely available at http://www.reproduction-online.org/content/147/4/427/suppl/DC1.

  14. Prediction of bull fertility.

    Science.gov (United States)

    Utt, Matthew D

    2016-06-01

    Prediction of male fertility is an often sought-after endeavor for many species of domestic animals. This review will primarily focus on providing some examples of dependent and independent variables to stimulate thought about the approach and methodology of identifying the most appropriate of those variables to predict bull (bovine) fertility. Although the list of variables will continue to grow with advancements in science, the principles behind making predictions will likely not change significantly. The basic principle of prediction requires identifying a dependent variable that is an estimate of fertility and an independent variable or variables that may be useful in predicting the fertility estimate. Fertility estimates vary in which parts of the process leading to conception that they infer about and the amount of variation that influences the estimate and the uncertainty thereof. The list of potential independent variables can be divided into competence of sperm based on their performance in bioassays or direct measurement of sperm attributes. A good prediction will use a sample population of bulls that is representative of the population to which an inference will be made. Both dependent and independent variables should have a dynamic range in their values. Careful selection of independent variables includes reasonable measurement repeatability and minimal correlation among variables. Proper estimation and having an appreciation of the degree of uncertainty of dependent and independent variables are crucial for using predictions to make decisions regarding bull fertility. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Conference considers low fertility.

    Science.gov (United States)

    1997-01-01

    At present, at least 51 countries--representing 44% of the world's population--are showing below-replacement fertility rates. In some of these countries, where the number of new births is not adequate to replace aging populations, this trend is problematic. In other countries, most notably China, declining fertility has conferred significant benefits. At an Economic and Social Commission for Asia and the Pacific (ESCAP) Population Commission meeting held in New York in 1997, staff from China's State Statistical Bureau reported the country has a current total fertility rate of 1.8. The birth rate remains high, however, because of the large numbers of Chinese women in the 15-49 year reproductive age group (336 million in 1997). Also buffering the impact of a low fertility rate is a large labor surplus (130 million excess workers in rural China). To keep fertility below the replacement level, China plans to improve the quality of its family planning service, enhance poverty alleviation programs, and increase incentives for small families in rural areas. China's low fertility rate has provided an important impetus for economic development.

  16. Fertility behavior in rural and urban Indonesia.

    Science.gov (United States)

    Chernichovsky, D; Newlon, B; Sigit, H

    1982-06-01

    The cross-sectional picture of urban and rural fertility which emerges from recently published Indonesian national level data from the 1976 Intercensal Survey are described. The data reveal only small differences in the average numbers of children ever born or children surviving of ever married women (or mothers) in urban and rural areas of Indonesia. In urban areas, ever married mothers had a standardized average of 3.4 children ever born, and in rural areas 3.3 These averages cannot reveal any differences in past and present childbearing levels. The fertility of urban women, as opposed to rural women, appeared more highly associated with indicators which tend to directly or indirectly depress the average number of children ever born: a higher age at 1st marriage; a higher level of "sterility;" a higher survival ratio of children born; and a higher level of educational attainment. At least some of these factors might be regarded as associated with modernizing trends in the urban areas: increased accessibility to educational facilities; the opening of female opportunities outside the home so that marriage occurs later in life; and a better health environment so that there is less pregnancy wastage and time spent in bearing children. These factors help to provide an incentive to women to limit their fertility; knowledge of contraception methods provides a means. The depressing factors most highly associated with average rural fertility do not appear associated with modernization but with traditional folk customs regarding acceptable behavior. The inflating effects of early marriage are offset by a greater prevalence of marital disruption. This may reflect a cultural acceptability. The reasons may include adolescent or true sterility leading to disunion, the outmigration of a partner, or some other form of disharmony. Female labor force participation is more prevalent in rural than urban areas. There are both traditional and modern aspects to be seen in its

  17. The impact of development and population policies on fertility in India.

    Science.gov (United States)

    Jain, A K

    1985-01-01

    This article examines the impact of development and population policies on fertility decline and regional variations in India during the 1970s. Indicators of development at the household level include female literacy and education, infant mortality, and poverty; at the village level they include availability of such social services as schools, medical facilities, and transportation and communication facilities. Multiple regression analysis of data aggregated at the state level demonstrates that conditions conducive to fertility decline include high adult female literacy and low infant mortality as indicators of social development, and high contraceptive use and, to a lesser extent, high female age at marriage as proximate determinants of fertility. There are reasons to believe that India's national family planning program contributed to the decline in fertility observed since the 1960s. The pace of fertility decline in the future will depend upon the pace of infant mortality decline, enhancement in female education, and improvements in family planning programs.

  18. Gender equity and fertility intentions in Italy and the Netherlands

    Directory of Open Access Journals (Sweden)

    Maria Letizia Tanturri

    2008-02-01

    Full Text Available Fertility levels have fallen drastically in most industrialized countries. Diverse theoretical and empirical frameworks have had difficulty in explaining these unprecedented low levels of fertility. More recently, however, attention has turned from classic explanations, such as women's increased labour market participation, to gender equity as the essential link to understand this phenomenon. The increase in women's labour market participation did not prompt an increase in men's domestic duties, which is often referred to women's 'dual burden' or 'second shift'. Institutions and policies within countries also facilitate or constrain the combination of women's employment with fertility. This paper provides an empirical test of gender equity theory by examining whether the unequal division of household labour leads to lower fertility intentions of women in different institutional contexts. Italy constitutes a case of high gender inequity, low female labour market participation and the lowest-low fertility. The Netherlands has moderate to low gender inequity, high part-time female labour market participation and comparatively higher fertility. Using data from the 2003 Italian Multipurpose Survey - Family and Social Actors and the 2004/5 Dutch sample from the European Social Survey, a series of logistic regression models test this theory. A central finding is that the unequal division of household labour only has a significant impact on women's fertility intentions when they already carry the load of high paid work hours or children, a finding that is particularly significant for working women in Italy.

  19. Radioactivity in Chemical Fertilizers

    International Nuclear Information System (INIS)

    Jankovic, M.; Nikolic, J.; Pantelic, G.; Rajacic, M.; Sarap, N.; Todorovic, D.

    2013-01-01

    The fertilizers are essential in agriculture as they supply nutrients to the farming fields. One of the sources of radioactivity other than those of natural origin is mainly due to extensive use of fertilizers. The concentrations of natural radionuclides, 40K, 226Ra, 238U and 235U in different chemical fertilizers, which are part of the regular control of imported goods from the border crossing were analyzed using gamma spectrometry with a high purity germanium (HPGe) detector, relative efficiency 20 %, in order to assess the implications of the extended use of chemical fertilizers. Measurements were performed at Vinca Institute, Radiation and Environmental Protection Department. The obtained results show remarkable wide variations in the radioactivity contents of different samples. The mean (ranges) of specific activities for gamma activity of those fertilizer samples for 40K, 226Ra, 238U and 235U are 4857 (23 - 12 324) Bq/kg, 87 (4-393) Bq/kg, 220 (26-1145) Bq/kg and 15 (1.6-53) Bq/kg, respectively. The radium equivalent activity (Ra eq ) as well as the external absorbed gamma dose rate (D) for all samples was also calculated.(author)

  20. Fertility counseling and preservation practices in youth with lupus and vasculitis undergoing gonadotoxic therapy.

    Science.gov (United States)

    Nahata, Leena; Sivaraman, Vidya; Quinn, Gwendolyn P

    2016-11-01

    To assess fertility counseling and preservation practices among children, adolescents, and young adults with rheumatic diseases undergoing cyclophosphamide (CTX) treatment. Retrospective chart review (2006-2016). Academic pediatric center. Male and female patients with systemic lupus erythematosus, Wegener's granulomatosis/granulomatosis with polyangiitis, or other vaculitides, receiving CTX treatment. None. Documentation of fertility counseling and fertility preservation. A total of 58 subjects met the inclusion criteria; 5 were excluded due to incomplete records, thus N = 53. Of these 75% were female (N = 40). Median age was 14 years at diagnosis and 15 years at first CTX treatment. A total of 51% of subjects (69% of males and 45% of females) had no documentation about potential fertility loss before CTX treatment. Among females where fertility counseling was documented, the only fertility preservation option discussed was leuprolide acetate (LA), which was pursued in all of these cases. Of 13 males (77% postpubertal), 3 were offered sperm banking, of whom 2 declined and the other attempted after treatment began and was azoospermic. Of 53 patients, 1 was referred to a fertility specialist. Mean cumulative CTX dose was 9.2 g in males and 8 g in females. Based on these findings, increasing awareness about infertility risk, fertility preservation options, and referral to fertility specialists is needed among pediatric rheumatologists. Prospective studies are needed to assess fertility outcomes in this patient population (including effectiveness of LA with regard to pregnancy rates [PRs]), as well as barriers/facilitators to fertility counseling and fertility preservation. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  1. Fusion: a tale of recombination in an asexual fungus: The role of nuclear dynamics and hyphal fusion in horizontal chromosome transfer in Fusarium oxysporum

    NARCIS (Netherlands)

    Shahi, S.

    2016-01-01

    Recent studies have shown that not only meiotic recombination is responsible for the fast evolution of fungal pathogens. In the asexual fungus F. oxysporum (Fo) the "fast" evolving part of the genome is organized into small chromosomes and one such chromosome houses all effector genes and is

  2. The role of sexual vs. asexual recruitment of Artemisia wudanica in transition zone habitats between inter-dune lowlands and active dunes in Inner Mongolia, China

    Science.gov (United States)

    Wang, Yongcui; Alberto, Busso Carlos; Jiang, Deming; Ala, Musa; Li, Xuehua; Zhou, Quanlai; Lin, Jixiang; Ren, Guohua; Jia, Lian

    2016-04-01

    Artemisia wudanica is an endemic, perennial, pioneering psammophyte species in the sand dune ecosystems of western Horqin Sand Land in northern China. However, no studies have addressed how sexual and asexual reproduction modes of A. wudanica perform at the transitional zones between active dune inter-dune lowlands and active dunes. In early spring, quadrats were randomly set up in the study area to monitor surviving seedling and/or ramet density and frequency coming from sexual/asexual reproduction of A. wudanica. Iron sticks were inserted near each quadrat to determine wind erosion intensity (WE). Additionally, soil samples were collected nearby each quadrat to test for soil moisture (SM), organic matter (OM) and pH. Surviving seedlings of A. wudanica showed an inverse response in comparison with ramets to SM, OM and WE. Soil moisture showed the most positive effect, and WE the negative effect, on surviving, sexual reproduction seedlings. Contrarily, WE had the most positive effect, and SM the negative effect, on asexual reproduction ramets. This suggests that increases in SM and decreases in WE should benefit recruitment of A. wudanica seedlings. On the contrary, ramets coming from asexual reproduction showed a different response to environmental factors in transition zone habitats. While SM was not a key constraint for the survival of seedlings, they showed a better, positive response to wind erosion environments. Overall, various study environmental parameters could be improved to foster A. wudanica invasion and settlement in the plant community through different reproductive modes, thereby promoting vegetation restoration and rehabilitation.

  3. A Gene Expressed during Sexual and Asexual Sporulation in Phytophthora infestans is a Member of the Puf Family of Translational Regulators

    DEFF Research Database (Denmark)

    Cvitanich, Cristina; Judelson, Howard S.

    2003-01-01

    and persisted in mature oospores. Expression was also observed in hyphal tips just prior to asexual sporulation, in sporangiophores, in mature sporangia, and in zoospores. The signal quickly disappeared once spores made the transition to hyphae after germination. Nutrient limitation did not induce the gene...

  4. The fertilizer nitrogen problem

    Energy Technology Data Exchange (ETDEWEB)

    Olson, R A; Halstead, E H

    1974-07-01

    A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

  5. The fertilizer nitrogen problem

    International Nuclear Information System (INIS)

    Olson, R.A.; Halstead, E.H.

    1974-01-01

    A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

  6. Identification of a Golgi apparatus protein complex important for the asexual erythrocytic cycle of the malaria parasite Plasmodium falciparum.

    Science.gov (United States)

    Hallée, Stéphanie; Thériault, Catherine; Gagnon, Dominic; Kehrer, Jessica; Frischknecht, Friedrich; Mair, Gunnar R; Richard, Dave

    2018-03-26

    Compared with other eukaryotic cell types, malaria parasites appear to possess a more rudimentary Golgi apparatus being composed of dispersed, unstacked cis and trans-cisternae. Despite playing a central role in the secretory pathway of the parasite, few Plasmodium Golgi resident proteins have been characterised. We had previously identified a new Golgi resident protein of unknown function, which we had named Golgi Protein 1, and now show that it forms a complex with a previously uncharacterised transmembrane protein (Golgi Protein 2, GP2). The Golgi Protein complex localises to the cis-Golgi throughout the erythrocytic cycle and potentially also during the mosquito stages. Analysis of parasite strains where GP1 expression is conditionally repressed and/or the GP2 gene is inactivated reveals that though the Golgi protein complex is not essential at any stage of the parasite life cycle, it is important for optimal asexual development in the blood stages. © 2018 John Wiley & Sons Ltd.

  7. Fertility and the economy.

    Science.gov (United States)

    Becker, G S

    1992-08-01

    Fertility and the economy is examined in the context of the Malthusian question about the links between family choices and longterm economic growth. Micro level differences are not included not are a comprehensive range of economic or determinant variables. Specific attention is paid to income and price effects, the quality of children, overlapping generations, mortality effects, uncertainty, and economic growth. Fertility and the demand for children in linked to parental incomes and the cost of rearing children, which is affected by public policies that change the costs. Demand is also related to child and adult mortality, and uncertainty about sex of the child. Fertility in one generation affects fertility in the next. Malthusian and neoclassical models do not capture the current model of modern economies with rising income/capita and human and physical capital, extensive involvement of married women in the labor force, and declining fertility to very low levels. In spite of the present advances in firm knowledge about the relationships between fertility and economic and social variables, there is still much greater ignorance of the interactions. The Malthusian utility function that says fertility rises and falls with income did hold up to 2 centuries of scrutiny, and the Malthusian inclusion of the shifting tastes in his analysis could be translated in the modern context to include price of children. The inclusion of net cost has significant consequences, i.e., rural fertility can be higher because the cost of rearing when children contribute work to maintaining the farm is lower than in the city. An income tax deduction for children in the US reduces cost. Economic growth raises the cost of children due the time spent on child care becoming more valuable. The modern context has changed from Malthusian time, and the cost of education, training, and medical care is relevant. The implication is that a rise in income could reduce the demand for children when

  8. Immigrant fertility in Sweden, 2000-2011: A descriptive note

    Directory of Open Access Journals (Sweden)

    Lotta Persson

    2014-03-01

    Full Text Available Background: Modern Scandinavian population registers provide excellent data sources that allow a user to quickly gain an impression of the level of fertility and its structure across subpopulations. This may also allow the analyst to check a feature of the much-cited disruption hypothesis, at least in part. Objective: The purpose of this note is to exploit this potential to give an overview of the structure of recent total fertility after immigration to Sweden from various groups of sending countries, separately for males and females. In the process we demonstrate to what extent the post-migration fertility compensation which is part of the fertility disruption hypothesis is fulfilled in our study population. Due to the nature of our data we have refrained from studying fertility before migration. Methods: Based on data from a combination of two Swedish administrative registers (the Historic Population Register and the Multi-Generation Register that cover both men and women in the entire population for the years 2000-2011, we compute and plot TFR-like age-cumulated fertility levels, specific for years since immigration, for six groups of sending countries, separately for men and women. Results: We find that the post-migration fertility compensation specified as part of the fertility disruption hypothesis is visibly confirmed in our Swedish study population for female European immigrants from non-EU countries and for female immigrants from non-European countries with a low or medium UN Human Development Index, but not so for other female immigrants, i.e. not for those who come from a Nordic country or from a non-Nordic EU country, and not for female immigrants from a non-European country with a high Human Development Index, including the United States. We find mild but less conclusive evidence for the same feature for males. Conclusions: This shows that at least as far as post-migration fertility compensation is concerned, the disruption

  9. Male meiosis in Crustacea: synapsis, recombination, epigenetics and fertility in Daphnia magna.

    Science.gov (United States)

    Gómez, Rocío; Van Damme, Kay; Gosálvez, Jaime; Morán, Eugenio Sánchez; Colbourne, John K

    2016-09-01

    We present the first detailed cytological study of male meiosis in Daphnia (Crustacea: Branchiopoda: Cladocera)-an aquatic microcrustacean with a cyclical parthenogenetic life cycle. Using immunostaining of the testes in Daphnia magna for baseline knowledge, we characterized the different stages of meiotic division and spermiogenesis in relation to the distribution of proteins involved in synapsis, early recombination events and sister chromatid cohesion. We also studied post-translational histone modifications in male spermatocytes, in relation to the dynamic chromatin progression of meiosis. Finally, we applied a DNA fragmentation test to measure sperm quality of D. magna, with respect to levels of inbreeding. As a proxy for fertility, this technique may be used to assess the reproductive health of a sentinel species of aquatic ecosystems. Daphnia proves to be a model species for comparative studies of meiosis that is poised to improve our understanding of the cytological basis of sexual and asexual reproduction.

  10. Globalization and Contemporary Fertility Convergence.

    Science.gov (United States)

    Hendi, Arun S

    2017-09-01

    The rise of the global network of nation-states has precipitated social transformations throughout the world. This article examines the role of political and economic globalization in driving fertility convergence across countries between 1965 and 2009. While past research has typically conceptualized fertility change as a country-level process, this study instead employs a theoretical and methodological framework that examines differences in fertility between pairs of countries over time. Convergence in fertility between pairs of countries is hypothesized to result from increased cross-country connectedness and cross-national transmission of fertility-related schemas. I investigate the impact of various cross-country ties, including ties through bilateral trade, intergovernmental organizations, and regional trade blocs, on fertility convergence. I find that globalization acts as a form of social interaction to produce fertility convergence. There is significant heterogeneity in the effects of different cross-country ties. In particular, trade with rich model countries, joint participation in the UN and UNESCO, and joining a free trade agreement all contribute to fertility convergence between countries. Whereas the prevailing focus in fertility research has been on factors producing fertility declines, this analysis highlights specific mechanisms-trade and connectedness through organizations-leading to greater similarity in fertility across countries. Globalization is a process that propels the spread of culturally laden goods and schemas impinging on fertility, which in turn produces fertility convergence.

  11. Coevolution of interacting fertilization proteins.

    Directory of Open Access Journals (Sweden)

    Nathaniel L Clark

    2009-07-01

    Full Text Available Reproductive proteins are among the fastest evolving in the proteome, often due to the consequences of positive selection, and their rapid evolution is frequently attributed to a coevolutionary process between interacting female and male proteins. Such a process could leave characteristic signatures at coevolving genes. One signature of coevolution, predicted by sexual selection theory, is an association of alleles between the two genes. Another predicted signature is a correlation of evolutionary rates during divergence due to compensatory evolution. We studied female-male coevolution in the abalone by resequencing sperm lysin and its interacting egg coat protein, VERL, in populations of two species. As predicted, we found intergenic linkage disequilibrium between lysin and VERL, despite our demonstration that they are not physically linked. This finding supports a central prediction of sexual selection using actual genotypes, that of an association between a male trait and its female preference locus. We also created a novel likelihood method to show that lysin and VERL have experienced correlated rates of evolution. These two signatures of coevolution can provide statistical rigor to hypotheses of coevolution and could be exploited for identifying coevolving proteins a priori. We also present polymorphism-based evidence for positive selection and implicate recent selective events at the specific structural regions of lysin and VERL responsible for their species-specific interaction. Finally, we observed deep subdivision between VERL alleles in one species, which matches a theoretical prediction of sexual conflict. Thus, abalone fertilization proteins illustrate how coevolution can lead to reproductive barriers and potentially drive speciation.

  12. A STUDY OF FEMALE CIRCUMCISION AMONG THE ISOKO TRIBE ...

    African Journals Online (AJOL)

    drclement

    2009-12-01

    Dec 1, 2009 ... women's health, sexuality and fertility. Objective: To ... them showed a high significant rate of circumcision (66%) ... female genital cutting by its critics) has been practiced ..... mutilation is falling, indicating that it has decreasing ...

  13. Correlations in fertility across generations: can low fertility persist?

    Science.gov (United States)

    Kolk, Martin; Cownden, Daniel; Enquist, Magnus

    2014-01-01

    Correlations in family size across generations could have a major influence on human population size in the future. Empirical studies have shown that the associations between the fertility of parents and the fertility of children are substantial and growing over time. Despite their potential long-term consequences, intergenerational fertility correlations have largely been ignored by researchers. We present a model of the fertility transition as a cultural process acting on new lifestyles associated with fertility. Differences in parental and social influences on the acquisition of these lifestyles result in intergenerational correlations in fertility. We show different scenarios for future population size based on models that disregard intergenerational correlations in fertility, models with fertility correlations and a single lifestyle, and models with fertility correlations and multiple lifestyles. We show that intergenerational fertility correlations will result in an increase in fertility over time. However, present low-fertility levels may persist if the rapid introduction of new cultural lifestyles continues into the future. PMID:24478294

  14. Fertilizing Southern Hardwoods

    Science.gov (United States)

    W. M. Broadfoot; A. F. Ike

    1967-01-01

    If present trends continue, fertilizing may soon be economically feasible in southern hardwood stands. Demands for the wood are rising, and the acreage alloted for growing it is steadily shrinking. To supply anticipated requests for information, the U. S. Forest Service has established tree nutrition studies at the Southern Hardwoods Laboratory in Stoneville,...

  15. Fertilizer micro-dosing

    International Development Research Centre (IDRC) Digital Library (Canada)

    Localized application of small quantities of fertilizer (micro-dosing), combined with improved planting pits for rainwater harvesting, has generated greater profits and food security for women farmers in the Sahel. • Women are 25% more likely to use combined applications, and have expanded areas of food crops (cowpea,.

  16. Fertility and Infertility.

    Science.gov (United States)

    Orgebin-Crist, Marie-Claire; And Others

    In this report, emphasis is placed on major research developments in the reproductive sciences, their impact on the health of individuals as well as on that of society, and on current trends that may provide new opportunities for future research in fertility and infertility. In the first section, major developments in the reproductive sciences are…

  17. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  18. Sex and Fertility After SCI

    Science.gov (United States)

    ... Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries ... Coping with a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. ...

  19. Agriculture: Nutrient Management and Fertilizer

    Science.gov (United States)

    Fertilizers and soil amendments can be derived from raw materials, composts and other organic matter, and wastes, such as sewage sludge and certain industrial wastes. Overuse of fertilizers can result in contamination of surface water and groundwater.

  20. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Resources Peer Counseling Blog About Media Donate close search Understanding Spinal Cord Injury What is a Spinal ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ...

  1. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord ... a New Injury Robin Dorman, PsyD Sex and Fertility After Spinal Cord Injury Diane M. Rowles, MS, ...

  2. Foods That Can Affect Fertility

    Science.gov (United States)

    ... That Can Affect Fertility Print Email Foods That Can Affect Fertility By Caroline Kaufman, MS, RDN Published ... the American Society for Reproductive Medicine. While couples can't control all of the causes of infertility, ...

  3. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... male fertility? play_arrow Where can people get information on sex and fertility after a spinal cord ... health care products or services, or control the information found on external websites. The Hill Foundation is ...

  4. Marijuana, the Endocannabinoid System and the Female Reproductive System

    OpenAIRE

    Brents, Lisa K.

    2016-01-01

    Marijuana use among women is highly prevalent, but the societal conversation on marijuana rarely focuses on how marijuana affects female reproduction and endocrinology. This article reviews the current scientific literature regarding marijuana use and hypothalamic-pituitary-ovarian (HPO) axis regulation, ovarian hormone production, the menstrual cycle, and fertility. Evidence suggests that marijuana can reduce female fertility by disrupting hypothalamic release of gonadotropin releasing hormo...

  5. Socioeconomic status and fertility decline

    DEFF Research Database (Denmark)

    Dribe, Martin; Breschi, Marco; Gagnon, Alain

    2017-01-01

    America to analyse the relationship between socio-economic status and fertility during the fertility transition. Using comparable analytical models and class schemes for each population, we examined the changing socio-economic differences in marital fertility and related these to common theories...

  6. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Provider Pocket Guides Provider Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ... Patient Pocket Guides Patient Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ...

  7. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ...

  8. Fertility Preservation for Children Diagnosed with Cancer

    Science.gov (United States)

    ... Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ... with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for ...

  9. Advanced reproductive age and fertility.

    Science.gov (United States)

    Liu, Kimberly; Case, Allison

    2011-11-01

    To improve awareness of the natural age-related decline in female and male fertility with respect to natural fertility and assisted reproductive technologies (ART) and provide recommendations for their management, and to review investigations in the assessment of ovarian aging. This guideline reviews options for the assessment of ovarian reserve and fertility treatments using ART with women of advanced reproductive age presenting with infertility. The outcomes measured are the predictive value of ovarian reserve testing and pregnancy rates with natural and assisted fertility. Published literature was retrieved through searches of PubMed or Medline, CINAHL, and The Cochrane Library in June 2010, using appropriate key words (ovarian aging, ovarian reserve, advanced maternal age, advanced paternal age, ART). Results were restricted to systematic reviews, randomized controlled trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated into the guideline to December 2010. The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table). Primary and specialist health care providers and women will be better informed about ovarian aging and the age-related decline in natural fertility and about options for assisted reproductive technology. 1. Women in their 20s and 30s should be counselled about the age-related risk of infertility when other reproductive health issues, such as sexual health or contraception, are addressed as part of their primary well-woman care. Reproductive-age women should be aware that natural fertility and assisted reproductive technology success (except with egg donation) is significantly lower for women in their late 30s and 40s. (II-2A) 2. Because of the decline in fertility and the

  10. Knowledge about factors that influence fertility among Australians of reproductive age: a population-based survey.

    Science.gov (United States)

    Hammarberg, Karin; Setter, Tracey; Norman, Robert J; Holden, Carol A; Michelmore, Janet; Johnson, Louise

    2013-02-01

    To explore knowledge about the effects on fertility of age, obesity, smoking, and timing of intercourse among Australians of reproductive age. Telephone survey of a representative sample of Australians. Not applicable. Australians aged 18 to 45 years who wish to have a child or another child now or in the future. None. Knowledge about the effect on fertility of age, obesity, smoking, and timing of intercourse. A total of 462 interviews were conducted. The majority of respondents underestimated, by about 10 years, the age at which male and female fertility starts to decline. Only one in four correctly identified that female fertility starts to decline before age 35, and one in three identified that male fertility starts to decline before age 45. Most (59%) were aware that female obesity and smoking affect fertility, but fewer recognized that male obesity (30%) and smoking (36%) also influence fertility. Almost 40% of respondents had inadequate knowledge of when in the menstrual cycle a woman is most likely to conceive. Considerable knowledge gaps about modifiable factors that affect fertility were identified. These are targeted in a national education campaign to promote awareness of factors that influence fertility. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. The dose effect of irradiated rice pollen on double fertilization

    International Nuclear Information System (INIS)

    Wang Houcong; Chen Zhengming; Chen Ruming; Qiu Simi; Yang Juemin; Yang Huijie

    1995-01-01

    The mature panicles of rice were treated with 60 Co γ-rays in the range of 0∼0.372 kGy. The male sterile line used as the female plants were fertilized with γ-irradiated pollen manually. The dose effect of the irradiated pollen on double fertilization was investigated. It was found that double fertilization of the irradiated pollen was suppressed to different degrees as compared with the control. The effect was noticeable as that the fusion time of the male nucleolus with the female one was delayed with the increasing of γ-radiation dose. The delayed time was less than 13 hours when the dose was below 0.186 kGy and it was more than 15 hours when the dose was above 0.279 kGy. Furthermore, several types of deformed embryonic cells and endosperm nuclei were observed

  12. Time trends in biological fertility in Western Europe

    DEFF Research Database (Denmark)

    Joffe, Michael; Holmes, Jane; Jensen, Tina Kold

    2013-01-01

    analyses demonstrated that this rise was visible as a male cohort effect for both TTP and contraceptive failure. On the other hand, the female birth cohort effect showed a slight fall in the first half of the study period for both TTP and contraceptive failure. As a period effect, fertility remained...... of which are calculated to be small. The declining female fertility accords with a falling dizygotic twinning rate during the same period.......We investigated trends in biological fertility in a comprehensive analysis of 5 major European data sets with data on time to pregnancy (TTP) and proportion of contraceptive failures. In particular, we distinguished a period effect from a birth cohort effect (lifelong tendency) in both sexes...

  13. Fertility in midlife women.

    Science.gov (United States)

    Yoldemir, T

    2016-06-01

    Reduced maternal fertility is the consequence of depletion of follicles with maternal aging. In a 35-year-old woman, approximately 9.1% of the residual follicle pool disappears annually without entering into the growing stage, whereas, in a 45-year-old woman, this number triples. After the age of 35 years, the frequency of aneuploidies in oocytes increases sharply. Roughly 50-70% of mature oocytes from a 40-year-old woman have chromosomal abnormalities. The clinical pregnancy and implantation rates are lower in midlife women. Various controlled ovarian stimulation interventions have been suggested for the management of women in advanced age, most of whom are likely to be poor-responder patients. Currently, systematic reviews and meta-analyses suggest that there is insufficient evidence to recommend most of the treatments proposed to improve pregnancy rates in these poor responders. Minimal stimulation or natural cycle in vitro fertilization may be offered, without compromising the already existing pregnancy results.

  14. Status of fertility control in Egypt.

    Science.gov (United States)

    Hefnawi, F I

    1982-01-01

    The concern for fertility control is not alien to the cultural and religious heritage of Egypt. Historically, Egyptian interest in fertility dates to the Pharoahs. Contraceptive recipes written at least 15-18 centuries B.C. have been found. Romans may have borrowed some of the more effective methods from Egypt when it became part of the Roman Empire as evidenced by the decline in size of aristocratic Roman families at the beginning of the Christian era. Muslim conquerors of Egypt encouraged fertility control. In the 9th century differences of opinion about the legality of contraception appeared among the interpreters of Islamic law. Some methods found in the writings of Muslim doctors as al-Razi and Avicenna still survive in the folk medicine of Egypt. In modern times use of barrier methods of contraception were encouraged by family planning organizations in Egypt. The medical profession was not deeply involved since these methods did not require much medical assistance. In 1936 a religiouss verdict declared contraception to be a lawful act of Islam. National programs in family planning in the 1960's encouraged the use of the Lippes Loop IUD. The medical problem of blood loss associated with the IUD caused anxiety because of the high incidence of anemia in the female Egyptian population. There was also a cultural limitation on the wide use of the IUD. "Spotting" due to the IUD resulted in females being ritually unclean and therefore unfit to pray or observe the Islamic fast. The Pill, initially favored caused complications due to its effect on breast milk which is the universal source of nutrition for infants in Egypt. Replacement of the Pill by depo-provera injections during the post partum period of lactation is a practical solution. Permanent sterilization is limited to females and only performed when medically indicated. Abortion is illegal and permitted only as a therapeutic measure.

  15. Too old to have children? Lessons from natural fertility populations

    NARCIS (Netherlands)

    Eijkermans, M.J.C.; van Poppel, F.W.A.; Habbema, J.D.F.; Smith, K.R.; Leridon, H.; te Velde, E.R.

    2014-01-01

    study question: Is it possible to construct an age curve denoting the ages above which women are biologically too old to reproduce? summaryanswer:We constructed a curve based on the distribution of female age at last birth in natural fertility populations reflecting the ages above which women have

  16. Preconception care: The influence of nutrition and lifestyle on fertility

    NARCIS (Netherlands)

    F. Hammiche (Fatima)

    2012-01-01

    textabstractIn Western societies there has been a change in reproductive behaviour with a tendency towards more couples postponing childbearing. As a consequence the number of couples experiencing impaired fertility in the Netherlands is rising. Female age in this respect is the commonly studied

  17. Fertility preservation 2

    Science.gov (United States)

    De Vos, Michel; Smitz, Johan; Woodruff, Teresa K

    2014-01-01

    Enhanced long-term survival rates of young women with cancer and advances in reproductive medicine and cryobiology have culminated in an increased interest in fertility preservation methods in girls and young women with cancer. Present data suggest that young patients with cancer should be referred for fertility preservation counselling quickly to help with their coping process. Although the clinical application of novel developments, including oocyte vitrification and oocyte maturation in vitro, has resulted in reasonable success rates in assisted reproduction programmes, experience with these techniques in the setting of fertility preservation is in its infancy. It is hoped that these and other approaches, some of which are still regarded as experimental (eg, ovarian tissue cryopreservation, pharmacological protection against gonadotoxic agents, in-vitro follicle growth, and follicle transplantation) will be optimised and become established within the next decade. Unravelling the complex mechanisms of activation and suppression of follicle growth will not only expand the care of thousands of women diagnosed with cancer, but also inform the care of millions of women confronted with reduced reproductive fitness because of ageing. PMID:25283571

  18. Soil and fertilizer nitrogen

    International Nuclear Information System (INIS)

    Winteringham, F.P.W.

    1984-01-01

    As a result of the intensified practices and effectively diminishing land resources per capita, increasing weights of both native soil- and added fertilizer-nitrogen will be lost to agriculture and its products, and will find their way into the environment. Soil-nitrogen levels and contingent productivity can nevertheless be maintained in the face of these losses on the basis of improved soil-N management. In some local situations nitrate levels in water for drinking purposes are likely to continue rising. In some cases agriculture and clearance practices are only one of several sources. In others they are clearly mainly responsible. In developing countries these losses represent those of a relatively increasingly costly input. This is due to the fact that industrial fertilizer nitrogen production is a particularly high energy-consuming process. In the more advanced industrialized countries they represent an addition to the problems and costs of environmental quality and health protection. The programmes, information and data reviewed here suggest that these problems can be contained by improved and extended soil and water management in agriculture on the basis of existing technology. In particular there appears to be enormous scope for the better exploitation of existing legumes both as non-legume crop alternatives or as biofertilizers which also possess more desirable C:N ratios than chemical fertilizer

  19. Fertility impairment in radiotherapy

    Directory of Open Access Journals (Sweden)

    Marta Biedka

    2016-02-01

    Full Text Available Infertility as a result of antineoplastic therapy is becoming a very important issue due to the growing incidence of neoplastic diseases. Routinely applied antineoplastic treatments and the illness itself lead to fertility disorders. Therapeutic methods used in antineoplastic treatment may cause fertility impairment or sterilization due to permanent damage to reproductive cells. The risk of sterilization depends on the patient’s sex, age during therapy, type of neoplasm, radiation dose and treatment area. It is known that chemotherapy and radiotherapy can lead to fertility impairment and the combination of these two gives an additive effect. The aim of this article is to raise the issue of infertility in these patients. It is of growing importance due to the increase in the number of children and young adults who underwent radiotherapy in the past. The progress in antineoplastic therapy improves treatment results, but at the same time requires a deeper look at existential needs of the patient. Reproductive function is an integral element of self-esteem and should be taken into account during therapy planning.

  20. The fertility decline in Kenya.

    Science.gov (United States)

    Robinson, W C; Harbison, S F

    1995-01-01

    In Sub-Saharan Africa Kenya is a prime example of a country experiencing a rapid decline in fertility and greater contraceptive prevalence. These changes have occurred since 1980 when fertility was high at 8.0 children per woman. In 1993 the total fertility rate (TFR) was 5.4, and the growth rate declined to about 2.0%. This transition is swifter than any country in contemporary Asia or historical Europe. The likely projection for Kenya is attainment of replacement level fertility during the 2020s and a leveling of population at about 100 million persons. Fertility has declined the most in urban areas and central and eastern regions. Bongaarts' proximate determinants (TFR, total marital fertility rate, total natural marital fertility rate, and total fecundity) are reduced to the proportion of currently married women using contraception, the proportion in lactational nonfecund status, and the proportion currently married. Actual fertility change is accounted for by total fertility change of 3.0 children. Lactational infecundability accounts for 0.5 potential births, and changes in marital fertility account for 1.0 reduced births per woman. About 70% of fertility reduction is accounted for by contraception and abortion. During 1977-78 80% of fertility control was due to lactational nonfecundity, 10% to nonmarriage, and 10% to contraception. In 1993 lactational nonfecundity accounted for 50% of the reduction, nonmarriage for 20%, and abortion about 30%. Future fertility is expected to be dependent on contraceptive prevalence. Kenya has experienced the Coale paradigm of preconditions necessary for demographic transition (willing, ready, and able). High fertility in Africa is not intractable. Creating the change in attitudes that leads to readiness is linked to education, health, and exposure to modernizing media and urban lifestyles. The public sector family planning program in Kenya has created the opportunity for access and availability of contraception. The key

  1. Chinese culture and fertility decline.

    Science.gov (United States)

    Wu, C; Jia, S

    1992-01-01

    Coale has suggested that cultural factors exert a significant influence on fertility reduction; countries in the "Chinese cultural circle" would be the first to show fertility decline. In China, the view was that traditional Chinese culture contributed to increased population. This paper examines the nature of the relationship between Chinese culture and fertility. Attention was directed to a comparison of fertility rates of developing countries with strong Chinese cultural influence and of fertility within different regions of China. Discussion was followed by an explanation of the theoretical impact of Chinese culture on fertility and direct and indirect beliefs and practices that might either enhance or hinder fertility decline. Emigration to neighboring countries occurred after the Qing dynasty. Fertility after the 1950s declined markedly in Japan, Singapore, Hong Kong, South Korea, Taiwan, and mainland China: all countries within the Chinese cultural circle. Other countries within the Chinese circle which have higher fertility, yet lower fertility than other non-Chinese cultural countries, are Malaysia, Thailand, and Indonesia. Within China, regions with similar fertility patterns are identified as coastal regions, central plains, and mountainous and plateau regions. The Han ethnic group has lower fertility than that of ethnic minorities; regions with large Han populations have lower fertility. Overseas Chinese in East Asian countries also tend to have lower fertility than their host populations. Chinese culture consisted of the assimilation of other cultures over 5000 years. Fertility decline was dependent on the population's desire to limit reproduction, favorable social mechanisms, and availability of contraception: all factors related to economic development. Chinese culture affects fertility reduction by affecting reproductive views and social mechanisms directly, and indirectly through economics. Confucianism emphasizes collectivism, self

  2. Female offenders

    NARCIS (Netherlands)

    Vivienne de Vogel; Marijke Louppen

    2017-01-01

    Although girls and women represent only a minority of the forensic mental health and prison populations, studies worldwide suggest that there has been a steady increase in the number of females being convicted for committing offenses, especially violent offenses. In this chapter, an overview will

  3. Fitness consequences of occasional outcrossing in a functionally asexual plant (Oenothera biennis).

    Science.gov (United States)

    Maron, John L; Johnson, Marc T J; Hastings, Amy P; Agrawal, Anurag A

    2018-02-01

    Many clonal organisms occasionally outcross, but the long-term consequences of such infrequent events are often unknown. During five years, representing three to five plant generations, we followed 16 experimental field populations of the forb, Oenothera biennis, originally planted with the same 18 original genotypes. Oenothera biennis usually self fertilizes, which, due to its genetic system (permanent translocation heterozygosity), results in seeds that are clones of the maternal plant. However, rare outcrossing produces genetically novel offspring (but without recombination or increased heterozygosity). We sought to understand whether novel genotypes produced through natural outcrossing had greater fecundity or different multigenerational dynamics compared to our original genotypes. We further assessed whether any differences in fitness or abundances through time between original and novel genotypes were exaggerated in the presence vs. absence of insect herbivores. Over the course of the experiment, we genotyped >12,500 plants using microsatellite DNA markers to identify and track the frequency of specific genotypes and estimated fecundity on a subset (>3,000) of plants. The effective outcrossing rate was 7.3% in the first year and ultimately 50% of the plants were of outcrossed origin by the final year of the experiment. Lifetime fruit production per plant was on average 32% higher across all novel genotypes produced via outcrossing compared to the original genotypes, and this fecundity advantage was significantly enhanced in populations lacking herbivores. Among 43 novel genotypes that were abundant enough to phenotype with replication, plants produced nearly 30% more fruits than the average of their specific two parental genotypes, and marginally more fruits (8%) than their most fecund parent. Mean per capita fecundity of novel genotypes predicted their relative frequencies at the end of the experiment. Novel genotypes increased more dramatically in

  4. Sponge budding is a spatiotemporal morphological patterning process: Insights from synchrotron radiation-based x-ray microtomography into the asexual reproduction of Tethya wilhelma

    OpenAIRE

    Hammel, J. U.; Herzen, J.; Beckmann, F.; Nickel, M.

    2009-01-01

    Abstract Background Primary agametic-asexual reproduction mechanisms such as budding and fission are present in all non-bilaterian and many bilaterian animal taxa and are likely to be metazoan ground pattern characters. Cnidarians display highly organized and regulated budding processes. In contrast, budding in poriferans was thought to be less specific and related to the general ability of this group to reorganize their tissues. Here we test the hypothesis of morphological pattern formation ...

  5. The gynogenetic reproduction of diploid and triploid hybrid spined loaches (Cobitis: Teleostei), and their ability to establish successful clonal lineages - on the evolution of polyploidy in asexual vertebrates

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel; Bohlen, Jörg; Lamatsch, D.; Flajšhans, Martin; Epplen, J. T.; Ráb, Petr; Kotlík, Petr; Šlechtová, Věra

    2007-01-01

    Roč. 131, - (2007), s. 185-194 ISSN 0016-6707 R&D Projects: GA ČR GP206/05/P586 Grant - others:EU Marie Curie Research amd Training Network(EU) MCRTN-CT-2004-512492; German Research Foundation(DE) SFB 567 Institutional research plan: CEZ:AV0Z50450515 Keywords : asexual reproduction * evolution of polyploidy * hybridisation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.396, year: 2007

  6. No detectable fertility benefit from a single additional mating in wild stalk-eyed flies.

    Directory of Open Access Journals (Sweden)

    Elisabeth Harley

    2010-12-01

    Full Text Available Multiple mating by female insects is widespread, and the explanation(s for repeated mating by females has been the subject of much discussion. Females may profit from mating multiply through direct material benefits that increase their own reproductive output, or indirect genetic benefits that increase offspring fitness. One particular direct benefit that has attracted significant attention is that of fertility assurance, as females often need to mate multiply to achieve high fertility. This hypothesis has never been tested in a wild insect population.Female Malaysian stalk-eyed flies (Teleopsis dalmanni mate repeatedly during their lifetime, and have been shown to be sperm limited under both laboratory and field conditions. Here we ask whether receiving an additional mating alleviates sperm limitation in wild females. In our experiment one group of females received a single additional mating, while a control group received an interrupted, and therefore unsuccessful, mating. Females that received an additional mating did not lay more fertilised eggs in total, nor did they lay proportionately more fertilised eggs. Female fertility declined significantly through time, demonstrating that females were sperm limited. However, receipt of an additional mating did not significantly alter the rate of this decline.Our data suggest that the fertility consequences of a single additional mating were small. We discuss this effect (or lack thereof, and suggest that it is likely to be attributed to small ejaculate size, a high proportion of failed copulations, and the presence of X-linked meiotic drive in this species.

  7. Robust inducible Cre recombinase activity in the human malaria parasite Plasmodium falciparum enables efficient gene deletion within a single asexual erythrocytic growth cycle.

    Science.gov (United States)

    Collins, Christine R; Das, Sujaan; Wong, Eleanor H; Andenmatten, Nicole; Stallmach, Robert; Hackett, Fiona; Herman, Jean-Paul; Müller, Sylke; Meissner, Markus; Blackman, Michael J

    2013-05-01

    Asexual blood stages of the malaria parasite, which cause all the pathology associated with malaria, can readily be genetically modified by homologous recombination, enabling the functional study of parasite genes that are not essential in this part of the life cycle. However, no widely applicable method for conditional mutagenesis of essential asexual blood-stage malarial genes is available, hindering their functional analysis. We report the application of the DiCre conditional recombinase system to Plasmodium falciparum, the causative agent of the most dangerous form of malaria. We show that DiCre can be used to obtain rapid, highly regulated site-specific recombination in P. falciparum, capable of excising loxP-flanked sequences from a genomic locus with close to 100% efficiency within the time-span of a single erythrocytic growth cycle. DiCre-mediated deletion of the SERA5 3' UTR failed to reduce expression of the gene due to the existence of alternative cryptic polyadenylation sites within the modified locus. However, we successfully used the system to recycle the most widely used drug resistance marker for P. falciparum, human dihydrofolate reductase, in the process producing constitutively DiCre-expressing P. falciparum clones that have broad utility for the functional analysis of essential asexual blood-stage parasite genes. © 2013 John Wiley & Sons Ltd.

  8. The impact of freedom on fertility decline.

    Science.gov (United States)

    Campbell, Martha M; Prata, Ndola; Potts, Malcolm

    2013-01-01

    Although fertility decline often correlates with improvements in socioeconomic conditions, many demographers have found flaws in demographic transition theories that depend on changes in distal factors such as increased wealth or education. Human beings worldwide engage in sexual intercourse much more frequently than is needed to conceive the number of children they want, and for women who do not have access to the information and means they need to separate sex from childbearing, the default position is a large family. In many societies, male patriarchal drives to control female reproduction give rise to unnecessary medical rules constraining family planning (including safe abortion) or justifying child marriage. Widespread misinformation about contraception makes women afraid to adopt modern family planning. The barriers to family planning can be so deeply infused that for many women the idea of managing their fertility is not considered an option. Conversely, there is evidence that once family planning is introduced into a society, then it is normal consumer behaviour for individuals to welcome a new technology they had not wanted until it became realistically available. We contend that in societies free from child marriage, wherever women have access to a range of contraceptive methods, along with correct information and backed up by safe abortion, family size will always fall. Education and wealth can make the adoption of family planning easier, but they are not prerequisites for fertility decline. By contrast, access to family planning itself can accelerate economic development and the spread of education.

  9. Asexual propagation of sea anemones that host anemonefishes: implications for the marine ornamental aquarium trade and restocking programs.

    Science.gov (United States)

    Scott, Anna; Hardefeldt, Jannah M; Hall, Karina C

    2014-01-01

    Anemonefishes and their host sea anemones form an iconic symbiotic association in reef environments, and are highly sought after in the marine aquarium trade. This study examines asexual propagation as a method for culturing a geographically widespread and commonly traded species of host sea anemone, Entacmaea quadricolor. Two experiments were done: the first to establish whether size or colour morph influenced survival after cutting into halves or quarters; and the second to see whether feeding was needed to maximise survival and growth after cutting. Survival rates were high in both experiments, with 89.3 and 93.8% of the anemones cut in half, and 62.5 and 80.4% cut in quarters surviving in experiments 1 and 2, respectively. Anemones that were cut in half were larger in size, and healed and grew quicker than those cut in quarters. However, even though survival was lower when the individuals were cut in quarters, this treatment produced the greatest number of anemones. Feeding increased oral disc diameter growth and reduced wet weight loss, but did not significantly influence pedal disc diameter. Given that the anemones took up to 56 d to form an off-centre mouth, it is highly likely that feeding may have produced greater effect if the experiment was run for longer. This low technology method of propagation could be used to produce individuals throughout the year and the anemones could then be used to supply the aquarium trade or restock depleted habitats, thus supporting biodiversity conservation in coral reef areas.

  10. Homogeneous population of the brown alga Sargassum polycystum in Southeast Asia: possible role of recent expansion and asexual propagation.

    Directory of Open Access Journals (Sweden)

    Sze Wai Chan

    Full Text Available Southeast Asia has been known as one of the biodiversity hotspots in the world. Repeated glacial cycles during Pleistocene were believed to cause isolation of marine taxa in refugia, resulting in diversification among lineages. Recently, ocean current was also found to be another factor affecting gene flow by restricting larval dispersal in animals. Macroalgae are unique in having mode of reproduction that differs from that of animals. Our study on the phylogeographical pattern of the brown macroalga Sargassum polycystum using nuclear Internal Transcribed Spacer 2 (ITS2, plastidal RuBisCO spacer (Rub spacer and mitochondrial cytochrome oxidase subunit-III (Cox3 as molecular markers revealed genetic homogeneity across 27 sites in Southeast Asia and western Pacific, in sharp contrast to that revealed from most animal studies. Our data suggested that S. polycystum persisted in single refugium during Pleistocene in a panmixia pattern. Expansion occurred more recently after the Last Glacial Maximum and recolonization of the newly flooded Sunda Shelf could have involved asexual propagation of the species. High dispersal ability through floating fronds carrying developing germlings may also contribute to the low genetic diversity of the species.

  11. Genomic and metabolic characterisation of alkaloid biosynthesis by asexual Epichloë fungal endophytes of tall fescue pasture grasses.

    Science.gov (United States)

    Ekanayake, Piyumi N; Kaur, Jatinder; Tian, Pei; Rochfort, Simone J; Guthridge, Kathryn M; Sawbridge, Timothy I; Spangenberg, German C; Forster, John W

    2017-06-01

    Symbiotic associations between tall fescue grasses and asexual Epichloë fungal endophytes exhibit biosynthesis of alkaloid compounds causing both beneficial and detrimental effects. Candidate novel endophytes with favourable chemotypic profiles have been identified in germplasm collections by screening for genetic diversity, followed by metabolite profile analysis in endogenous genetic backgrounds. A subset of candidates was subjected to genome survey sequencing to detect the presence or absence and structural status of known genes for biosynthesis of the major alkaloid classes. The capacity to produce specific metabolites was directly predictable from metabolic data. In addition, study of duplicated gene structure in heteroploid genomic constitutions provided further evidence for the origin of such endophytes. Selected strains were inoculated into meristem-derived callus cultures from specific tall fescue genotypes to perform isogenic comparisons of alkaloid profile in different host backgrounds, revealing evidence for host-specific quantitative control of metabolite production, consistent with previous studies. Certain strains were capable of both inoculation and formation of longer-term associations with a nonhost species, perennial ryegrass (Lolium perenne L.). Discovery and primary characterisation of novel endophytes by DNA analysis, followed by confirmatory metabolic studies, offers improvements of speed and efficiency and hence accelerated deployment in pasture grass improvement programs.

  12. Poverty, Fertility and Child Labor: Does Demand Theory of Fertility Matter? An Exploratory Study in India

    Directory of Open Access Journals (Sweden)

    Gargi Bhattacharya

    2013-07-01

    Full Text Available It is hypothesized that fertility, poverty and child labor are jointly determined variables; neither can be assumed to be an independent determinant of the other. In a simultaneous equation framework, we find that demand theory of fertility does hold good even at the lower level of income where the females are compelled to go outside home for cash in order to avoid destitute and they prefer less number of children. Therefore, in order to regulate fertility in India, one can suggest increasing female employment opportunity at the informal sector, since formal sector job is severely restricted in India. It is observed that child labor is caused by lower health status and poor human capital investment. Thus, if we increase the per capita social sector expenditure on education and healthcare, it directly augments enrollment of the children in school. Since health and education is treated as complementary to each other, a rise in social sector investment has some spillover benefits to the society.

  13. Suppression of fertility in adult cats

    DEFF Research Database (Denmark)

    Goericke-Pesch, Sandra Kathrin; Wehrend, A.; Georgiev, P.

    2014-01-01

    /needed? (iii) sex of the animal? New effective and available methods for hormonal contraception include melatonin implants for short-term post ponement of oestrus in adult queens and slow-release GnRH-agonist implants containing deslorelin (Suprelorin®) for short- and long-term contraception in male and female......Contents: Cats are animals with highly efficient reproduction, clearly pointing to a need for suppression of fertility. Although surgical contraception is highly effective, it is not always the method of choice. This is predominantly because it is cost-intensive, time-consuming and irreversible......, with the latter being of major importance for cat breeders. This article reviews the use of progestins, scleroting agents, immunocontraception, melatonin, GnRH antagonists and finally, GnRH agonists, in adult male and female cats in detail, according to the present state of the art. By now, various scientific...

  14. Immunosuppressive drugs and fertility.

    Science.gov (United States)

    Leroy, Clara; Rigot, Jean-Marc; Leroy, Maryse; Decanter, Christine; Le Mapihan, Kristell; Parent, Anne-Sophie; Le Guillou, Anne-Claire; Yakoub-Agha, Ibrahim; Dharancy, Sébastien; Noel, Christian; Vantyghem, Marie-Christine

    2015-10-21

    Immunosuppressive drugs are used in the treatment of inflammatory and autoimmune diseases, as well as in transplantation. Frequently prescribed in young people, these treatments may have deleterious effects on fertility, pregnancy outcomes and the unborn child. This review aims to summarize the main gonadal side effects of immunosuppressants, to detail the effects on fertility and pregnancy of each class of drug, and to provide recommendations on the management of patients who are seen prior to starting or who are already receiving immunosuppressive treatment, allowing them in due course to bear children. The recommendations for use are established with a rather low level of proof, which needs to be taken into account in the patient management. Methotrexate, mycophenolate, and le- and teri-flunomide, cyclophosphamide, mitoxanthrone are contraindicated if pregnancy is desired due to their teratogenic effects, as well as gonadotoxic effects in the case of cyclophosphamide. Anti-TNF-alpha and mTOR-inhibitors are to be used cautiously if pregnancy is desired, since experience using these drugs is still relatively scarce. Azathioprine, glucocorticoids, mesalazine, anticalcineurins such as cyclosporine and tacrolimus, ß-interferon, glatiramer-acetate and chloroquine can be used during pregnancy, bearing in mind however that side effects may still occur. Experience is limited concerning natalizumab, fingolimod, dimethyl-fumarate and induction treatments. Conclusion: At the time of prescription, patients must be informed of the possible consequences of immunosuppressants on fertility and of the need for contraception. Pregnancy must be planned and the treatment modified if necessary in a pre-conception time period adapted to the half-life of the drug, imperatively in relation with the prescriber of the immunosuppressive drugs.

  15. Ethnicity and fertility in Nigeria.

    Science.gov (United States)

    Kollehlon, Konia T

    2003-01-01

    Using a sample of Hausa-Fulani, Yoruba, Ibo, and all other women from the 1990 Nigerian Demographic and Health Survey, this study examines ethnic fertility differentials in Nigeria within the context of the social characteristics and cultural hypotheses. Among all women, we find the net fertility of Hausa-Fulani women to be lower than that of Other women; with no statistically significant difference in the net fertility of Ibo, Yourba, and Other women. But, among currently married women, we find the net fertility of Hausa-Fulani and Yoruba women to be lower than that of Other women, while the net fertility of Ibo women is higher than that of Other women. Overall, the findings of this study are more consistent with the cultural hypothesis, because statistically significant fertility differentials by ethnicity remain, even after controlling for selected socioeconomic and demographic variables.

  16. Temporal Trends in Fertility Rates

    DEFF Research Database (Denmark)

    Jensen, Martin Blomberg; Priskorn, Lærke; Jensen, Tina Kold

    2015-01-01

    OBJECTIVE: Increasing age at first childbirth has been suggested to increase the risk for infertility. Our objective is to determine whether women above thirty years of age historically have been able to sustain fertility rates above replacement level. DESIGN: A descriptive nationwide Danish study...... to determine total and age specific fertility rates. RESULTS: Total fertility rate (TFR) decreased from 4.1 to 1.8 children per woman and age specific fertility also decreased from 1901 to 2014. Women aged 30-34, 35-39 or 40-44 years in the first decade of the 20th century had higher fertility rates than...... for 10% of TFR in 1901 compared with 4% in 2014 despite usage of assisted reproduction. CONCLUSION: This nationwide study shows that women above 30 years of age historically have been able to sustain fertility rates above replacement level. This implies that other factors besides age are strong...

  17. Does fertility decrease household consumption?

    OpenAIRE

    Jungho Kim; Henriette Engelhardt; Alexia Fürnkranz-Prskawetz; Arnstein Aassve

    2009-01-01

    This paper presents an empirical analysis of the relationship between fertility and a direct measure of poverty for Indonesia, a country, which has experienced unprecedented economic growth and sharp fertility declines over recent decades. It focuses on illustrating the sensitivity of the effect of fertility on household consumption with respect to the equivalence scale by applying the propensity score matching method. The analysis suggests that a newborn child decreases household consumption...

  18. Fertility differentials in rural Bangladesh.

    Science.gov (United States)

    Khan, H T; Islam, S M; Khan, H M; Bari, R

    1993-01-01

    "Data from two sources in rural Bangladesh have been used in this study to examine the differentials in fertility by selected socio-economic and demographic factors. Results [indicate] that age at first marriage, education of spouses and availability of electricity in the household...have [an] inverse relationship with fertility. Higher fertility is observed for Muslim women than for non-Muslims. It has been found that fertility is the lowest to those women whose husbands are service holders and the highest for agriculture." excerpt

  19. Fertilization compatibility of spawning corals

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set includes experimental results of fertilization assays to characterize genetic compatibility between individual parental genotypes. Targeted species...

  20. The beginning of a seed: regulatory mechanisms of double fertilization.

    Science.gov (United States)

    Bleckmann, Andrea; Alter, Svenja; Dresselhaus, Thomas

    2014-01-01

    THE LAUNCH OF SEED DEVELOPMENT IN FLOWERING PLANTS (ANGIOSPERMS) IS INITIATED BY THE PROCESS OF DOUBLE FERTILIZATION: two male gametes (sperm cells) fuse with two female gametes (egg and central cell) to form the precursor cells of the two major seed components, the embryo and endosperm, respectively. The immobile sperm cells are delivered by the pollen tube toward the ovule harboring the female gametophyte by species-specific pollen tube guidance and attraction mechanisms. After pollen tube burst inside the female gametophyte, the two sperm cells fuse with the egg and central cell initiating seed development. The fertilized central cell forms the endosperm while the fertilized egg cell, the zygote, will form the actual embryo and suspensor. The latter structure connects the embryo with the sporophytic maternal tissues of the developing seed. The underlying mechanisms of double fertilization are tightly regulated to ensure delivery of functional sperm cells and the formation of both, a functional zygote and endosperm. In this review we will discuss the current state of knowledge about the processes of directed pollen tube growth and its communication with the synergid cells resulting in pollen tube burst, the interaction of the four gametes leading to cell fusion and finally discuss mechanisms how flowering plants prevent multiple sperm cell entry (polyspermy) to maximize their reproductive success.

  1. Profiles of fertility, labour supply and wages of married women: a complete life-cycle model.

    Science.gov (United States)

    Moffitt, R

    1984-01-01

    Trends in fertility and female labor supply have changed dramatically since World War II. Fertility rates rose steadily from the 1940's until the early 1960's and thereafter declined, while female laborforce participation rates have continually grown since the 1950's. These 2 rates are closely linked. Labor supply and fertility decisions are also life-cycle decisions. In addition, wage and job prospects are related to job choice and in turn to fertility decisions. Labor supply, fertility, and wages are linked in an econometric model which takes into account the problems of heterogeneity of tastes, the problem of missing wage rates through nonworking, and the problem of simultaneous-equations bias. Past works are critiqued, mainly on the basis that few analyses recognize the interrelatedness of fertility and labor supply in any sense--static or dynamic. Nor do most researchers consider age-specific fertility equations in analyzing female labor supply. Moffitt's model is a beginning analysis of fertility and labor supply as a joint consumer-demand choice. Patterns of a couple's future consumption, wife's labor supply, and births are assumed to be planned at the beginning of marriage. These patterns depend on the constraints of budget, fertility, and of inverse production (the differing amounts of time it takes to care for a child as the child matures) as well as wage accumulation. Exogenous wealth and beginning wages are considered as well. This model does not account for a woman's work experience prior to marriage. According to the model, fertility rates rise in the 1st year of marriage and subsequently fall off. Employment rates drop off at an accelerating rate until the 6th year of marriage and then increase. A rise in wage level decreases the probability of birth and increases the probability ow working. Also, changes in fertility rates have more to do with wage changes than with a woman's cohort.

  2. Behavioural ecology: transient sexual mimicry leads to fertilization.

    Science.gov (United States)

    Hanlon, Roger T; Naud, Marié-Jose; Shaw, Paul W; Havenhand, Jon N

    2005-01-20

    Sexual mimicry among animals is widespread, but does it impart a fertilization advantage in the widely accepted 'sneak-guard' model of sperm competition? Here we describe field results in which a dramatic facultative switch in sexual phenotype by sneaker-male cuttlefish leads to immediate fertilization success, even in the presence of the consort male. These results are surprising, given the high rate at which females reject copulation attempts by males, the strong mate-guarding behaviour of consort males, and the high level of sperm competition in this complex mating system.

  3. Culture: an empirical investigation of beliefs, work, and fertility

    OpenAIRE

    Raquel Fernandez; Alessandra Fogli

    2005-01-01

    We study the effect of culture on important economic outcomes by using the 1970 Census to examine the work and fertility behaviour of women 30-40 years old, born in the US, but whose parents were born elsewhere. We use past female labour force participation and total fertility rates from the country of ancestry as our cultural proxies. These variables should capture, in addition to past economic and institutional conditions, the beliefs commonly held about the role of women in society, i.e. c...

  4. Household Fertilizers Use and Soil Fertility Management Practices ...

    African Journals Online (AJOL)

    Household Fertilizers Use and Soil Fertility Management Practices in Vegetable Crops Production: The Case of Central Rift Valley of Ethiopia. ... rate, which could leads to pollution of the environment from over dose application and from runoff in to the water bodies and leaching in to the ground water with economic loss.

  5. Fertile ground? : soil fertility management and the African smallholder

    NARCIS (Netherlands)

    Misiko, M.

    2007-01-01

    Keywords: smallholder farmers, soil fertility, experimentation, "inconvenience", realist.The focus in this thesis is to form a view of how well soil fertility research performs within the ever shifting smallholder contexts. This study examined application of agro-ecological

  6. Aging, fertility, and immortality.

    Science.gov (United States)

    Rauser, Casandra L; Mueller, Laurence D; Rose, Michael R

    2003-01-01

    Evolutionary theory suggests that fecundity rates will plateau late in life in the same fashion as mortality rates. We demonstrate that late-life plateaus arise for fecundity in Drosophila melanogaster. The result qualitatively fits the evolutionary theory of late life based on the force of natural selection. But there are a number of alternative interpretations. Fecundity plateaus could be secondary consequences of mortality-rate plateaus. Female fecundity plateaus might arise from diminished male sexual function. Another alternative hypothesis is analogous to male sexual inadequacy: nutritional shortfalls. These may arise later in life because of a decline in female feeding or digestion. If some females have a life-long tendency to lay eggs at a faster rate, but die earlier, then aging for fecundity could arise from the progressive loss of the fast-layers, with the late-life plateau simply the laying patterns of individual females who were slow-layers throughout adult life. If this type of model is generally applicable to late life, then we should find that the females who survive to lay at a slow but steady rate in late life have a similar laying pattern in mid-life.

  7. The fertility of recent migrants to England and Wales

    Directory of Open Access Journals (Sweden)

    James Robards

    2016-06-01

    Full Text Available Background: Estimates of fertility for the overseas-born based on the period Total Fertility Rate (TFR suggest that levels of childbearing are significantly higher among foreign-born women than women born in the UK. However, migration and timing of subsequent family formation mean that aggregate measures of fertility based on period TFRs may not be a useful indicator of the likely completed family size that migrant women will have at the end of their reproductive lives. Objective: The paper quantifies childbearing according to duration since migration among female migrants to England and Wales arriving between 2001 and 2011, and examines how these patterns differ according to age at arrival and country of birth. Methods: Data from the Office for National Statistics Longitudinal Study, a 1Š sample of the population of England and Wales, are used to identify the reported date of arrival in the UK and to estimate childbearing prior to and subsequent to arrival. Results: Fertility rates peak in the first one to four years subsequent to arrival among migrants from Pakistan and Bangladesh. Migrants from India and Poland show a delay in childbearing after migration to England and Wales, and lower fertility rates compared to migrants from Pakistan and Bangladesh, who show high fertility after migration at least for the first five years. Conclusions: There are large differences in the timing of fertility among migrants according to age at arrival and migrant country of origin, which are likely to be related to the reason for migration. Tempo distortions among some migrant groups mean that the period TFR is not necessarily a useful summary measure of the likely lifetime fertility of migrant groups.

  8. Female condoms.

    Science.gov (United States)

    Bounds, W

    1997-06-01

    Early versions of a female condom were available in the 1920s and 1960s, but they were little used and soon forgotten. It took the arrival of AIDS, and the urgent need for a wider range of female-controlled barrier techniques, to rekindle scientific interest in this method. In the 1980s, three groups in Europe and the USA began development of new female condom designs, comprising 'Femidom (Reality)', the 'Bikini Condom', and 'Women's Choice'. Apart from differences in their physical design, Femidom differs from the others in that it is made of a polyurethane membrane, which has several advantages over latex. Of the three, Femidom is the most advanced in terms of development and clinical testing, and it is the only one to have reached the marketing stage. Laboratory studies and clinical trials suggest that its contraceptive efficacy is similar to that documented for the male condom, though a direct comparison is not possible because no comparative clinical trials have, as yet, been undertaken. Reported 'typical-use' pregnancy rates range from 12.4 to 22.2% at 6 months of use in the USA and Latin America, respectively, while a study in the UK observed a rate of 15% at 12 months. As with all barrier methods, most failures appear to be associated with poor compliance or incorrect use. 'Perfect-use' pregnancy rates were substantially lower, indicating that Femidom can be very effective, if used consistently and correctly. Evidence for Femidom's effectiveness to protect against transmission of sexual disease-causing organisms, including HIV, is still very limited and based largely on laboratory studies. Whilst, in theory, the condom should confer reliable protection, its efficacy in clinical use will depend upon correct and consistent use and upon the product's ability to maintain an effective physical barrier throughout penetrative intercourse. In this respect, the results of recent and ongoing clinical studies are expected with much interest. How valuable Femidom will

  9. Prediction of porcine male fertility

    NARCIS (Netherlands)

    Broekhuijse, M.L.W.J.|info:eu-repo/dai/nl/313871728

    2012-01-01

    Life starts with fertilisation. Variation in fertility is caused by both farm and sow related parameters and boar and semen related parameters. Therefore, achieving high fertility is not obvious. Predominantly, artificial insemination (AI) is used for breeding pigs. The advantage of AI is that you

  10. Fertility treatment in obese women

    NARCIS (Netherlands)

    Koning, A.M.H.

    2015-01-01

    Overweight and obesity are increasing worldwide. This has major adverse consequences for health in general and fertility in women in particular. With the increasing number of women in reproductive age being obese, there is also an increasing need for fertility treatment. And with more pregnant women

  11. Fertility drugs and ovarian cancer.

    Science.gov (United States)

    Ali, Aus Tariq

    2017-06-20

    The aetiology of ovarian cancer is multifactorial with both endogenous and exogenous risk factors playing an important role. The exact pathogenesis of ovarian cancer is still not well understood, despite the number of hypotheses published. Due to an increase in the number of women using fertility drugs, much attention has been focused on the long-term health effects of such drugs. Although fertility drugs facilitate the ovulation process, it is however associated with a significant increase in hormone concentrations, placing exposed women at increased risk of gynaecological cancer. Many clinical and epidemiological studies have examined the association between fertility drugs and ovarian cancer risk. Results from these studies have been contradictory, as some studies have reported an increased risk of ovarian cancer while others reported no increased risk. Nevertheless, recent studies have shown that women who used fertility drugs and did not conceive had a higher risk of developing ovarian cancer, compared to women who used fertility drugs and conceived and delivered successfully. This review discusses the effect of fertility drugs on the risk of developing ovarian cancer, providing details on four possible scenarios associated with fertility treatment. In addition, the limitations of previous studies and their impact on our understanding of the association between fertility drugs and ovarian cancer also have been highlighted. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Fertilizing Douglas-fir forests.

    Science.gov (United States)

    Richard E. Miller; Roger D. Right

    1979-01-01

    This report supplements a slide-tape presentation of the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir forests in western Washington and Oregon and the effects of this fertilization on tree growth and water quality. Part II discusses factors that affect costs and revenues from investments in forest...

  13. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik

    1999-01-01

    To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss.......To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss....

  14. Asexual propagation of sea anemones that host anemonefishes: implications for the marine ornamental aquarium trade and restocking programs.

    Directory of Open Access Journals (Sweden)

    Anna Scott

    Full Text Available Anemonefishes and their host sea anemones form an iconic symbiotic association in reef environments, and are highly sought after in the marine aquarium trade. This study examines asexual propagation as a method for culturing a geographically widespread and commonly traded species of host sea anemone, Entacmaea quadricolor. Two experiments were done: the first to establish whether size or colour morph influenced survival after cutting into halves or quarters; and the second to see whether feeding was needed to maximise survival and growth after cutting. Survival rates were high in both experiments, with 89.3 and 93.8% of the anemones cut in half, and 62.5 and 80.4% cut in quarters surviving in experiments 1 and 2, respectively. Anemones that were cut in half were larger in size, and healed and grew quicker than those cut in quarters. However, even though survival was lower when the individuals were cut in quarters, this treatment produced the greatest number of anemones. Feeding increased oral disc diameter growth and reduced wet weight loss, but did not significantly influence pedal disc diameter. Given that the anemones took up to 56 d to form an off-centre mouth, it is highly likely that feeding may have produced greater effect if the experiment was run for longer. This low technology method of propagation could be used to produce individuals throughout the year and the anemones could then be used to supply the aquarium trade or restock depleted habitats, thus supporting biodiversity conservation in coral reef areas.

  15. Marginal coral populations: the densest known aggregation of Pocillopora in the Galápagos Archipelago is of asexual origin

    Directory of Open Access Journals (Sweden)

    Iliana B Baums

    2014-11-01

    Full Text Available Coral populations at distributional margins frequently experience suboptimal and variable conditions. Recurrent El Niño-Southern Oscillation (ENSO warming events have caused extensive mortality of reef-building corals in the Eastern Pacific, and particularly impacted branching pocilloporid corals in the Galápagos Islands. Pocillopora spp. were previously more common and formed incipient reefs at several locations in the Archipelago but now occur as scattered colonies. Here, we report an unusually concentrated aggregation of colonies and evaluate their current genetic diversity. In particular we focus on a large population of 1614 live Pocillopora colonies found in a volcanic lagoon along the southern shore of Isabela Island. Forty seven colonies were sampled, primarily using a spatially explicit sampling design, and all colonies belonged to Pocillopora mitochondrial open reading frame lineage type 3a. Typing of additional Pocillopora samples (n = 40 from three other islands indicated that this stand is the only known representative of type 3a in the Galápagos Islands. The Isabela Pocillopora type 3a colonies harbored Symbiodinium ITS-2 clade C1d. Multilocus genotyping (n = 6 microsatellites capable of resolving individual clones indicated that this stand is monogenotypic and thus the high density of colonies is a result of asexual reproduction, likely via fragmentation. Colony size distribution, while imperfect, suggested the stand regrew from remnant colonies that survived the 1997/98 ENSO event but may postdate the 1982/83 ENSO. The community of Pocillopora colonies at Isabela is of particular ecological value due to its high density and support of associated organisms such as fish and benthic invertebrates. The Galapagos Pocillopora corals will continue to provide insights into the genetic structure and population dynamics of marginal coral populations.

  16. Vital role for cyclophilin B (CypB) in asexual development, dimorphic transition and virulence of Beauveria bassiana.

    Science.gov (United States)

    Chu, Zhen-Jian; Sun, Huan-Huan; Ying, Sheng-Hua; Feng, Ming-Guang

    2017-08-01

    Cyclophilin B (CypB) was previously revealed as one of many putative secretory proteins in the transcriptome of Beauveria bassiana infection to a lepidopteran pest. Here we show a main localization of CypB in hyphal cell walls and septa and its essential role in the in vitro and in vivo asexual cycles of the fungal insect pathogen. Deletion of cypB reduced colony growth by 16-42% on two rich media and 30 scant media with different carbon or nitrogen sources. The deletion mutant suffered a delayed conidiation on a standard medium and a final 47% reduction in conidial yield, accompanied with drastic transcript depression of several key genes required for conidiation and conidial maturation. The mutant conidia required 10h longer to germinate 50% at optimal 25°C than wild-type conidia. Intriguingly, cultivation of the mutant conidia in a trehalose-peptone broth mimic to insect hemolymph resulted in 83% reduction in blastospore yield but only slight decrease in biomass level, indicating severe defects in transition of hyphae to blastospores. LT 50 for the deletion mutant against Galleria mellonella larvae through normal cuticle infection was prolonged to 7.4d from a wild-type estimate of 4.7d. During colony growth, additionally, the deletion mutant displayed hypersensitivity to Congo red, menadione, H 2 O 2 and heat shock but increased tolerance to cyclosporine A and rapamycin. All of changes were restored by targeted gene complementation. Altogether, CypB takes part in sustaining normal growth, aerial conidiation, conidial germination, dimorphic transition, stress tolerance and pathogenicity in B. bassiana. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. [Fertility and health in Mexico].

    Science.gov (United States)

    Urbina-Fuentes, M; Echánove-Fernández, E

    1989-01-01

    Fertility, health, and family planning are not independent factors, but rather involve a series of biological and social mechanisms in close interaction with one another. The impact that a high fertility rate has on health is reflected mainly in a rise in the rates of maternal and child mortality. Similarly, fertility has a greater negative effect upon the health of groups characterized by high reproductive risk, high parity, short intergenesic intervals, and unwanted pregnancies. On the other hand, family planning -and specifically the use of contraceptive methods-helps to achieve a lowering of the fertility rate and also has a positive effect on maternal-child health. This situation can be observed in the case of Mexico, where fertility rates and tendencies, as well as maternal and child mortality, have been reduced during the past decade.

  18. Isotope studies on rice fertilization

    International Nuclear Information System (INIS)

    1978-01-01

    The aim of the report is to provide practical information on the efficient utilization of nitrogen fertilizers in rice production. Results obtained from field investigations during the years 1970 to 1974 in ten countries (Bangladesh, Burma, Indonesia, Republic of Korea, Sri Lanka, Taiwan, Thailand, Vietnam, India, Philippines), using 15 N-labelled nitrogen fertilizers (ammonium sulfate, urea) are given. The experiments, which were conducted both during the dry and wet seasons, included comparison of varieties, effect of placement, source and time of nitrogen fertilizer application on the yield and quality of rice. The data from the project is presented in table form. In most of the experiments, the addition of nitrogen increased the rice grain yield. The role of soil nitrogen vs. fertilizer nitrogen is compared, and it is concluded that the physiological growth stage at which fertilizer-derived nitrogen is absorbed is of great importance

  19. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... options further? Fertility Preservation - Where Does It Fit? Options for Fertility Preservation The following diagram gives a brief description of fertility preservation options available to children diagnosed with cancer before and ...

  20. Fertilizers in cereals crops. Effect of fertilization in grain quality

    International Nuclear Information System (INIS)

    Melaj, Mariana

    1997-01-01

    In the last years the yields of the maize cultivation in the Pampeana production region have constantly increased, foreseeing higher increases of yield in the next years. Such increase is due, between other motives, to the use of hybrids of higher potential yield. There is a direct relation between the yield potential of a genotype and the nutrients demand, fact that constitutes one of the geneticists concerns. Maize hybrids reach its maximum expression when the plant is cultivated in good supplied soils with balanced quantities of nutrients that in several cases are reached with the practice of fertilization. The quantitative and qualitative vegetal response to the use of phosphate fertilizers depend of soils, of the environmental conditions, of fertilizer and the way of its application as well as of the maize hybrid that was used. To direct the practice of fertilization towards the reposition of the soil nutrients extracted by genotypes of high yield without producing excesses that increase costs and put in danger the environment, it is necessary to know the real coefficient used by the plants of the phosphorus available in the soils. The isotopic methodology allows to distinguish the phosphorus coming from two nutrient sources: soil and fertilizer, even in the juvenile phase of vegetal development and to evaluate the efficiency of fertilizers in plant nutrition. The objective of the present work was to evaluate the use of phosphorus coming from one of the phosphorus source available (soil, fertilizer), that should allow to increase and make more specific the knowledge's level of the different maize hybrids. This is obtained by determination of the grade of use of nutrient (of the soil) and of the nutrient of fertilizers, evaluating the qualitative and quantitative responses to fertilization

  1. The insults of illicit drug use on male fertility.

    Science.gov (United States)

    Fronczak, Carolyn M; Kim, Edward D; Barqawi, Al B

    2012-01-01

    One-third of infertile couples may have a male factor present. Illicit drug use can be an important cause of male factor infertility and includes use of anabolic-androgenic steroids, marijuana, opioid narcotics, cocaine, and methamphetamines. The use of these illicit drugs is common in the United States, with a yearly prevalence rate for any drug consistently higher in males compared with females. We aim to provide a review of recent literature on the prevalence and effects of illicit drug use on male fertility and to aid health professionals when counseling infertile men whose social history suggests illicit drug use. Anabolic-androgenic steroids, marijuana, cocaine, methamphetamines, and opioid narcotics all negatively impact male fertility, and adverse effects have been reported on the hypothalamic-pituitary-testicular axis, sperm function, and testicular structure. The use of illicit drugs is prevalent in our society and likely adversely impacting the fertility of men who abuse drugs.

  2. Too old to have children? Lessons from natural fertility populations.

    Science.gov (United States)

    Eijkemans, Marinus J C; van Poppel, Frans; Habbema, Dik F; Smith, Ken R; Leridon, Henri; te Velde, Egbert R

    2014-06-01

    Is it possible to construct an age curve denoting the ages above which women are biologically too old to reproduce? We constructed a curve based on the distribution of female age at last birth in natural fertility populations reflecting the ages above which women have become biologically too old to have children. The median age at last birth (ALB) for females is ∼40-41 years of age across a range of natural fertility populations. This suggests that there is a fairly universal pattern of age-related fertility decline. However, little is known about the distribution of female ALB and in the present era of modern birth control, it is impossible to assess the age-specific distribution of ALB. Reliable information is lacking that could benefit couples who envisage delaying childbearing. This study is a review of high-quality historical data sets of natural fertility populations in which the distributions of female age at last birth were analysed. The studies selected used a retrospective cohort design where women were followed as they age through their reproductive years. Using a common set of eligibility criteria, large data files of natural fertility populations were prepared such that the analysis could be performed in parallel across all populations. Data on the ALB and confounding variables are presented as box and whisker plots denoting the 5th, 25th, 50th, 75th and 95th percentile distribution of the age at last birth for each population. The analysis includes the estimation of Kaplan-Meier curves for age at last birth of each population. The hazard curve for ALB was obtained by plotting the smoothed hazard curve of each population and taking the lowest hazard within a time period of at least 5 years. This lowest hazard curve was then transformed into a cumulative distribution function representing the composite curve of the end of biological fertility. This curve was based on the data from three of the six populations, having the lowest hazards of end of

  3. Antenatal Diagnosis of an XXX Female

    Science.gov (United States)

    Krone, Lawrence R.; Prichard, Lorraine L.; Bradshaw, Christy L.; Jones, Oliver W.; Peterson, Raymond M.; Dixson, Barbara K.

    1975-01-01

    This report describes the first antenatal diagnosis of an XXX female. Over 150 postnatal cases of XXX females have been described. There is no specific phenotype associated with the sex chromosome abnormality and most such persons are fertile. The frequency of XXX females in mental institutions is 3.9 per 1,000 female subjects whereas the frequency in consecutive newborn infants is 1.1 per 1,000 newborns. Chi-square analysis shows this difference cannot be due to chance. On the other hand, data from consecutive newborn studies suggest that intellectual development in XXX newborns is within normal range. Available evidence favors normal development in XXX female infants although the risk for developmental disabilities may be higher for the XXX than for the XX infant. ImagesFigure 1. PMID:1154778

  4. Laparoscopic evaluation of female infertility

    International Nuclear Information System (INIS)

    Haiderr, G.; Rani, S.; Zehra, N.; Munir, A.

    2010-01-01

    Background: Sub-fertility is inability to ensure child bearing when it is wanted. Prevalence of sub-fertility in industrialised countries has been quoted as 20%, and seems to be on the rise. Traditional way to assess the uterine cavity, tubal structure and tubal patency was hysterosalpingography but it has now been largely superseded by laparoscopy and hysteroscopy. The objective of this study was to highlight the role of laparoscopy in establishing diagnosis of female infertility. Methods: This descriptive study was conducted in Gynaecology Unit of Liaquat University of Medical Health Sciences, Hyderabad, Pakistan from August 28, 2000 to July 1, 2001. Total 200 sub-fertile patients attended the gynaecology OPD. Out of these 30 patients were selected for laparoscopy and dye test who were suspected cases of endometriosis, abnormal HSG and unexplained infertility. Those patients who had medical disorders and contraindication for laparoscopy were excluded from study. Detailed history of every patient was recorded on a proforma and physical examination was performed. Laparoscopy was scheduled in proliferative phase of menstrual cycle. Data were analysed using SPSS 11. Frequency and percentages were calculated to describe the results. Results: Out of 200 sub-fertile patients total 30 patients were selected for laparoscopy. Twenty (66%) patients were in primary infertility group while 10 (33%) patients were in secondary infertility group. Eleven (55%) patients of primary infertility belong to age group of 18-25 years while 6(60%) patients of secondary infertility belong to age group of 26- 33 years. Mean duration of sub fertility at time of presentation in primary infertility group was 1.95 years while in secondary infertility was 2.70 years. In primary infertility group main associated symptoms were dysmenorrhoeal in 8 (40%), irregular cycles 5 (25%), and dyspareunia in 4 (20%). In secondary infertility group 3 (30%) patients had dysmenorrhoeal and dyspareunia while 2

  5. Fertility in Alberta in a Context of Rapid Economic Growth, 1997-2007

    Directory of Open Access Journals (Sweden)

    Frank Trovato

    2010-12-01

    Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to subreplacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman - not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change - that is, periods of economic growth are conducive to fertility increase whereas bad economic times are associated with reduced fertility.

  6. Fertility in Alberta in a Context of Rapid Economic Growth, 1997-2007

    Directory of Open Access Journals (Sweden)

    Frank Trovato

    2010-01-01

    Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to sub-replacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman---not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change --- that is, periods of economic growth are conducive to fertility increase whereas bad economic times lead to reduced fertility.

  7. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for ...

  8. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for Patients Many adult ...

  9. Age- and size-dependent mating performance and fertility in a pelagic copepod, Temora longicornis

    DEFF Research Database (Denmark)

    Sichlau, Mie Hylstofte; Kiørboe, Thomas

    2011-01-01

    Prepress abstract: In many species, size and age have been shown to be strong determinants of the reproductive success for both sexes. Here we examine age- and size dependent reproductive performance (egg- and sperm production, mating success) in a pelagic copepod. Compared to smaller males, larger...... males produce larger spermatophores containing more spermatozoa, and fertilize a larger fraction of available females. Females mating with large males produce more offspring than those mating with small males. Similarly, large females have higher egg production rates as well as a higher life-time egg...... fertilize females for only about eight days after they mature. The strong size- and age-dependent fertility observed in this species is conducive to the development of sexual selection via mate choice for young and large partners, as has been shown in one other copepod species...

  10. Comparison of unenriched versus 15N-enriched fertilizer as a tracer for N fertilizer uptake

    International Nuclear Information System (INIS)

    Meints, V.W.; Shearer, G.; Kohl, D.H.; Kurtz, L.T.

    1975-01-01

    A greenhouse experiment was conducted on three soils with differing cropping and fertilization histories to determine whether unenriched fertilizer N can be used in the same manner as 15 N-enriched fertilizer to estimate the amount of plant N derived from fertilizer. Estimates using unenriched fertilizer N were compared with estimates using two 15 N enrichment levels. Use of unenriched fertilizer N led to underestimation of the amount of fertilizer N in the plant material in four of six cases when compared to 15 N-enriched fertilizer. Standard deviations of the estimates of fertilizer-derived N in plant material were considerably greater when unenriched fertilizer was used. (U.S.)

  11. Incidence and prevalence of sexual dysfunction in infertile females

    Directory of Open Access Journals (Sweden)

    Rohina S. Aggarwal

    2013-09-01

    Results: In our study 170 (63.67% patients in the infertile group (n = 267 had female sexual dysfunction as compared to108 (46.35% in the fertile group (n = 233, which is statistically significant (P 0.0001. Most common dysfunction observed was arousal (70% in infertile patients. Common dysfunctions observed in fertile females were desire (40% and orgasm (40%. FSD was significantly higher in infertile females of the 31–37 years age group (P 0.002, while more common in fertile females of >42 years of age (P < 0.0001. Higher female sexual dysfunction was observed in illiterate infertile females (P 0.039. Among the pathological factors endometriosis was the statistically significant factor associated with female sexual dysfunction and infertility (P < 0.0001. No significant correlation in duration of infertility or type of infertility was observed with female sexual dysfunction. Female sexual dysfunction as the cause or the effect should be ascertained in infertility.

  12. Virus epidemics can lead to a population-wide spread of intragenomic parasites in a previously parasite-free asexual population.

    Science.gov (United States)

    Jalasvuori, Matti; Lehtonen, Jussi

    2014-03-01

    Sexual reproduction is problematic to explain due to its costs, most notably the twofold cost of sex. Yet, sex has been suggested to be favourable in the presence of proliferating intragenomic parasites given that sexual recombination provides a mechanism to confine the accumulation of deleterious mutations. Kraaijeveld et al. compared recently the accumulation of transposons in sexually and asexually reproducing lines of the same species, the parasitoid wasp Leptopilina clavipes. They discovered that within asexually reproducing wasps, the number of gypsy-like retrotransposons was increased fourfold, whereas other retrotransposons were not. Interestingly, gypsy-like retrotransposons are closely related to retroviruses. Endogenous retroviruses are retroviruses that have integrated to the germ line cells and are inherited thereafter vertically. They can also replicate within the genome similarly to retrotransposons as well as form virus particles and infect previously uninfected cells. This highlights the possibility that endogenous retroviruses could play a role in the evolution of sexual reproduction. Here, we show with an individual-based computational model that a virus epidemic within a previously parasite-free asexual population may establish a new intragenomic parasite to the population. Moreover and in contrast to other transposons, the possibility of endogenous viruses to maintain a virus epidemic and simultaneously provide resistance to individuals carrying active endogenous viruses selects for the presence of active intragenomic parasites in the population despite their deleterious effects. Our results suggest that the viral nature of certain intragenomic parasites should be taken into account when sex and its benefits are being considered. © 2014 John Wiley & Sons Ltd.

  13. Transmission rates of the bacterial endosymbiont, Neorickettsia risticii, during the asexual reproduction phase of its digenean host, Plagiorchis elegans, within naturally infected lymnaeid snails.

    Science.gov (United States)

    Greiman, Stephen E; Tkach, Vasyl V; Vaughan, Jefferson A

    2013-10-22

    Neorickettsia are obligate intracellular bacterial endosymbionts of digenean parasites present in all lifestages of digeneans. Quantitative information on the transmission of neorickettsial endosymbionts throughout the complex life cycles of digeneans is lacking. This study quantified the transmission of Neorickettsia during the asexual reproductive phase of a digenean parasite, Plagiorchis elegans, developing within naturally parasitized lymnaeid pond snails. Lymnaea stagnalis snails were collected from 3 ponds in Nelson County, North Dakota and screened for the presence of digenean cercariae. Cercariae were identified to species by PCR and sequencing of the 28S rRNA gene. Neorickettsia infections were initially detected using nested PCR and sequencing of a partial 16S rRNA gene of pooled cercariae shed from each parasitized snail. Fifty to 100 single cercariae or sporocysts were isolated from each of six parasitized snails and tested for the presence of Neorickettsia using nested PCR to estimate the efficiency at which Neorickettsia were transmitted to cercariae during asexual development of the digenean. A total of 616 L. stagnalis were collected and 240 (39%) shed digenean cercariae. Of these, 18 (8%) were Neorickettsia-positive. Six Neorickettsia infections were selected to determine the transmission efficiency of Neorickettsia from mother to daughter sporocyst and from daughter sporocyst to cercaria. The prevalence of neorickettsiae in cercariae varied from 11 to 91%. The prevalence of neorickettsiae in sporocysts from one snail was 100%. Prevalence of Neorickettsia infection in cercariae of Plagiorchis elegans was variable and never reached 100%. Reasons for this are speculative, however, the low prevalence of Neorickettsia observed in some of our samples (11 to 52%) differs from the high prevalence of other, related bacterial endosymbionts, e.g. Wolbachia in Wolbachia-dependent filariid nematodes, where the prevalence among progeny is universally 100

  14. Inbreeding, heterosis, fertility, plasmon differentiation and Phytophthora resistance in Solanum verrucosum Schlechtd., and some interspecific crosses in Solanum

    NARCIS (Netherlands)

    Abdalla, M.M.F.

    1970-01-01

    Solanum verrucosum (2n = 24) is a self-compatible, highly fertile species. This conclusion is drawn from the results of studies on 21 various introductions of this species. In spite of self-compatibility and good male and female fertility, the species generally needs a pollinating agent to

  15. Zinc fertilization of flooded rice

    International Nuclear Information System (INIS)

    1981-02-01

    Local scientists studied Zn fertilization of flooded rice soils in Bangladesh, India, Indonesia, the Republic of Korea, Egypt, the Philippines, Thailand and Turkey. Diagnosis of Zn deficiency was carried out for submerged rice soils. Soil maps were prepared, designating areas as low, medium and high in Zn, based on Zn extraction with DTPA and HCl solutions and on rice leaf analysis. The effectiveness of various Zn fertilizer sources and methods of application in field and greenhouse experiments was measured, using 65 Zn. The percent Zn derived from fertilizer was shown to be a much more sensitive measure of efficiency than yield or total uptake

  16. Effect of war on fertility: a review of the literature.

    Science.gov (United States)

    Abu-Musa, Antoine A; Kobeissi, Loulou; Hannoun, Antoine B; Inhorn, Marcia C

    2008-01-01

    The aim of this study was to review the existing literature on the effect of war on female and male fertility. A MEDLINE search for studies that included participants defined as infertile because they were unsuccessful in achieving a pregnancy after a year and studies that assessed the effect of war on semen parameters and menstrual dysfunction were performed. Twenty articles were included in this review. For female fertility, studies showed that women who were prisoners of war or who were living in areas exposed to bombardment had increased risk of menstrual abnormalities. For male fertility, the results were conflicting. The Vietnam War was not associated with difficulty in conception although one study revealed a decrease in sperm characteristics. Studies of male US and Danish 1990/91 Gulf war veterans showed no evidence of reduced fertility; however, studies of UK and Australian veterans reported increased risk of infertility. The Lebanese and Slovenian civil wars were associated with a decrease in sperm parameters. Exposure to mustard gas was also associated with abnormal semen parameters; however, exposure to depleted uranium had no effect on semen characteristics. Most of the studies examined had major limitations including recall bias and small number of cases included.

  17. Sexual and asexual reproduction in Didemnum rodriguesi (Ascidiacea, Didemnidae Reprodução sexuada e assexuada em Didemnum rodriguesi (Ascidiacea, Didemnidae

    Directory of Open Access Journals (Sweden)

    Nicole F. Ritzmann

    2009-03-01

    Full Text Available Sexual and asexual reproduction and associated population dynamics were investigated in the colonial ascidian Didemnum rodriguesi Rocha & Monniot, 1993 (Didemnidae in southern Brazil. Investment in sexual (production of new individuals and asexual (colony growth reproduction was compared between seasons. Permanently marked quadrats were repeatedly photographed to measure changes in colonies. Eggs and larvae were counted monthly in collected colonies. This species alternates seasonally between sexual (summer and asexual (winter reproduction. In summer, colonies were smaller, brooded eggs and larvae and recruitment rates were greater, while in winter, colony size was larger and eggs and larvae were absent. There is a relationship between fecundity and colony area. Fragmentation and fusion of colonies were similar in summer and winter, as well as mortality. In conclusion, D. rodriguesi has a lifecycle usual for high latitude ascidians with a limited time length for sexual reproduction and alternate investment in sexual and asexual reproduction along the year.Reprodução sexuada e assexuada, mortalidade e a dinâmica de fusões e fissões de colônias de Didemnum rodriguesi Rocha & Monniot, 1993 foram investigados e comparados no sul do Brasil, no inverno e verão. Tais eventos foram analisados por fotografias de áreas permanentemente demarcadas e coletas mensais de colônias. Os resultados indicam que esta espécie alterna sazonalmente a reprodução sexuada (verão e assexuada (inverno. Durante o verão as colônias são mais abundantes e menores, com ovos e larvas incubados e taxas de recrutamento maiores. No inverno há um menor número de colônias, porém de maior tamanho e inférteis. Existe uma relação entre fecundidade e tamanho da colônia. Não foram encontradas diferenças estatísticas no número de eventos de fragmentação e fusão entre o verão e inverno, bem como para mortalidade. Conclui-se que esta espécie tem um ciclo de

  18. Actividad inhibitoria de un polímero de quitosana en el crecimiento vegetativo y la reproducción asexual de un aislado de Phytophthora palmivora Butler

    OpenAIRE

    González-Peña Fundora, Dianevys; Gómez Izaguirre, Guadalupe; Fernández Morales, Ana; Vaillant Flores, Daymara; Falcón-Rodríguez, Alejandro B.

    2016-01-01

    El objetivo del trabajo fue evaluar el efecto de la quitosana sobre el crecimiento vegetativo y las fases de reproducción asexual del ciclo de vida de Phytophthora palmivora Butler. Soluciones con diferentes concentraciones de quitosana, que oscilaron desde 0,5 hasta 2,5g.l-1 se mezclaron con medio de cultivo V8 antes de verterse en placas Petri, donde luego se inoculó un disco de micelio del aislado. Se evaluaron aspectos morfoculturales y el crecimiento radial cuando las colonias del tratam...

  19. A Brazilian Population of the Asexual Fungus-Growing Ant Mycocepurus smithii (Formicidae, Myrmicinae, Attini) Cultivates Fungal Symbionts with Gongylidia-Like Structures

    DEFF Research Database (Denmark)

    Masiulionis, Virginia E.; Rabeling, Christian; de Fine Licht, Henrik Hjarvard

    2014-01-01

    gongylophorus. Higher agriculture fungal cultivars are characterized by specialized hyphal tip swellings, so-called gongylidia, which are considered a unique, derived morphological adaptation of higher attine fungi thought to be absent in lower attine fungi. Rare reports of gongylidia-like structures in fungus...... gardens of lower attines exist, but it was never tested whether these represent rare switches of lower attines to L. gonglyphorus cultivars or whether lower attine cultivars occasionally produce gongylidia. Here we describe the occurrence of gongylidia-like structures in fungus gardens of the asexual...

  20. Fertilization and Embryo Development of Fresh and Cryopreserved Sibling Oocytes

    Directory of Open Access Journals (Sweden)

    Robert F. Casper

    2010-01-01

    Full Text Available Background: Oocyte cryopreservation is potentially the best way to preserve female fertility forunmarried women or young girls at risk of losing ovarian function. The aim of this study was tocompare fertilization and embryo development in frozen-thawed oocytes to their fresh siblings inwomen undergoing in vitro fertilization (IVF and embryo transfer (ET.Materials and Methods: Eleven infertile women undergoing infertility treatment, between theages of 24 to 37 years (mean ± SD = 31.6 ± 3.5, were included in this study. Mature oocytesfrom each patient were randomized into cryopreserved and fresh groups prior to intracytoplasmicsperm injection (ICSI. One hundred and thirty nine oocytes were retrieved, of which 105 were atmetaphase II (MII. Forty- five fresh MII oocytes were kept in culture whereas their sibling 60 MIIoocytes were cryopreserved using a slow cooling protocol. The frozen oocytes remained in LN2for 2 hours before thawing. ICSI was performed 1-2 hours after thawing for frozen oocytes and 4-5hours after retrieval for fresh oocytes. Fertilization and embryo development were compared.Results: Following thawing, 31 oocytes (51.6 % survived and 22 fertilized (79% while 32 freshoocytes fertilized upon ICSI (71%. The mean ± SE scores for embryos developing from frozenthawedoocytes were significantly lower at 48 and 72 hours post-ICSI than for embryos resultingfrom fresh oocytes (p<0.05.Conclusion: Our data demonstrated that oocyte freezing resulted in acceptable survival ratesfollowing cryopreservation, and similar fertilization rates following ICSI as compared to the freshsibling oocytes. However the number of blastomeres and the embryo quality on day three wassuperior in embryos from fresh oocytes when compared to the frozen oocytes.

  1. Impact of migration on fertility in sub-Saharan Africa.

    Science.gov (United States)

    Brockerhoff, M; Yang, X

    1994-01-01

    Much lower levels of fertility in urban than rural areas throughout sub-Saharan Africa imply that fertility decline in the region may be facilitated by rapid urbanization and rural-to-urban migration. The present study uses data from Demographic and Health Surveys in six countries--Ghana, Kenya, Mali, Senegal, Togo and Uganda--to assess the impact of long-term rural-urban female migration on fertility. Results of logit analyses indicate that in most countries women who leave the countryside represent the higher fertility segment of the rural population in the years before migration. Migrants' risk of conception declines dramatically in all countries around the time of migration and remains lower in the long run among most migrant groups than among rural and urban nonmigrants. Descriptive analyses suggest that the decline in migrant fertility is related to the rapid and pronounced improvement in standard of living experienced by migrants after settling in the urban area and may be due in part to temporary spousal separation.

  2. Evaluating bull fertility based on non-return method

    Directory of Open Access Journals (Sweden)

    Prka Igor

    2012-01-01

    Full Text Available In order to evaluate the results of reproductive cows and heifers, different parameters of fertility are used, such as the service period, insemination index, intercalving time and others, and of the breeding bulls the values obtained through non-return. An ejaculate is taken up for further processing by veterinary centres only provided it meets the prescribed quality parameters. Rating semen parameters includes a macroscopic (volume, colour, consistency, smell and pH and a microscopic evaluation (mobility, density, percentage of live sperm and abnormal and damaged sperm. In addition to sperm quality and the fertility of the female animal, the results of the non-return method are also influenced by a number of exogenous causes (season, age, race, insemination techniques that have no small impact on the end result of insemination - pregnancy. In order to obtain more objective results of the fertility of bulls the following tasks were undertaken, namely: 1. to calculate with the non-return method the fertility of bulls in over 10,000 cows inseminated for the first time during a period of 6 years; and 2. to analyze the impact of semen quality, season, age of cow and bull, and the bull breed on the results of fertility.

  3. Semen collection and fertility in naturally fertile sandhill cranes

    Science.gov (United States)

    Chen, G.; Gee, G.F.; Nicolich, Jane M.; Taylor, J.A.; Urbanek, R.P.; Stahlecker, D.W.

    1997-01-01

    Aviculturists often ask if semen collection will interfere with fertility in naturally fertile pairs of cranes. We used 12 naturally fertile Florida sandhill crane (Grus canadensis pratensis) pairs for this study, 6 control and 6 experimental. All pairs had produced fertile eggs in previous years and were in out-of-doors pens scattered throughout different pen complexes, within auditory range but physically isolated. Semen was collected on Tuesday mornings and Friday afternoons from 26 February 1993 to 4 June 1993. We used standard artificial insemination methods to collect and to evaluate the semen and spermatozoa. Semen collection did not affect semen quality or quantity. Semen volume, sperm density, sperm motility, sperm morphology, sperm live, sperm number per collection, and male response to semen collection exhibited significant daily variation (P semen collection began 13 days before the first egg in the experimental group, we observed no differences in the date of first egg laid or in fertility between experimental and control groups. Also, we observed no differences in the interval between clutches or in the percentage of broken eggs between experimental and control groups. Sires consistently producing better semen samples produced fewer fertile eggs than sires producing poorer semen samples (r = 0.60).

  4. Fertility and Public Policies - Evidence from Norway and Finland

    Directory of Open Access Journals (Sweden)

    2004-05-01

    Full Text Available The relatively high and rising fertility rates of Nordic countries in the late 1980s and early 1990s sparked a renewed research interest in the possible pronatalistic effects of generous family policy programs. Several studies have addressed this issue, but few have tried to model policy effects explicitly. The existing evidence so far is mainly from Sweden, where policy indicators have been incorporated in economic fertility models that also control for female wages. This paper complements previous Swedish analyses with evidence from Norway and Finland. The results corroborate earlier findings of a negative effect of female wages. There are also indications of a positive policy impact, as maternity leave extensions are estimated to raise birth rates, although mainly higher parity births and mainly in Finland.

  5. Sexuality and fertility in women with Addison's disease.

    Science.gov (United States)

    Erichsen, Martina M; Husebye, Eystein S; Michelsen, Trond M; Dahl, Alv A; Løvås, Kristian

    2010-09-01

    Females with primary adrenal insufficiency (Addison's disease) have reduced levels of circulating androgens, which are allegedly important for sexual functioning. The aim was to determine peripheral androgen status, sexual functioning, and birth rates in Addison's disease females. In a postal survey, all 269 females in the Norwegian Addison's registry were invited to complete the Sexual Activity Questionnaire (SAQ) and registration of childbirths. Blood samples were analyzed for 5alpha-androstane-3alpha,17beta-diol-3-glucuronide (3alpha-Diol-G) and compared with blood donor levels. The SAQ scores were compared with 740 age-matched controls from the general population and 234 women subjected to risk-reducing salpingo-oophorectomy. Fertility was estimated as standardized incidence ratio for birth; the expected number of births was estimated from population statistics. The SAQ was completed by 174 (65%) of the Addison's patients. Those not taking DHEA had significantly lower 3alpha-Diol-G levels than blood donors (mean, 0.53 vs. 2.2 ng/ml; P Addison's disease females were equally sexually active as the controls, but they reported significantly higher pleasure and less discomfort. They reported lower pleasure but less discomfort than the risk-reducing salpingo-oophorectomy women. The fertility was significantly reduced in females with Addison's disease; 54 children were born to mothers with established diagnosis (87.5 expected), yielding a standardized incidence ratio for birth of 0.69 (confidence interval, 0.52-0.86). Despite androgen depletion, females with Addison's disease do not report impaired sexuality. The fertility is reduced after the diagnosis is made; the reasons for this remain unknown.

  6. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility ... injury? What is a Spinal Cord Injury? SCI Medical Experts People Living With SCI Personal Experiences By ...

  7. Determinants of fertility in Namibia

    African Journals Online (AJOL)

    AJRH Managing Editor

    This examines the fertility trends in Namibia over the past 2 decades .... contraceptive use was small because of the late age at first ..... limited flexibility in terms of maternity leave conditions ... Longer periods in education have increased the.

  8. In vivo fertilization of banana

    Directory of Open Access Journals (Sweden)

    Taliane Leila Soares

    2014-01-01

    Full Text Available The aim of this research was to study the in vivo fertilization process of banana cultivars. The diploid hybrid (AA 091087-01 was the male progenitor. Flower samples were checked for fertilization from the first to the twentieth day after pollination. The size of the diploid ovules increased gradually at the beginning of the seed formation process. On the other hand, in the AAA triploids (Cavendish subgroup, the not fertilized ovules were aborted. In the AAB triploids (Prata subgroup some ovules were fertilized. The flowers of Grand Naine, Nanicão and 'Pacovan' cultivars presented necrosis in the distal part of the ovary on the first day after pollination. Necrosis can hinder pollen tube growth towards the ovule, which might be related to the low seed yield in 'Pacovan' cultivars and to the absence of seeds in the Cavendish subgroup cultivars.

  9. Preserving Fertility while Battling Cancer

    Science.gov (United States)

    Some oncologists neglect to discuss the possibility of treatment-related infertility with patients of reproductive age. Researchers are developing decision aids to help patients make an informed, carefully considered decision about fertility.

  10. Determinants of fertility in Ethiopia

    African Journals Online (AJOL)

    be access to education, media, and providing employment opportunities in the modern economic sector. Besides .... and religion shows that muslim women have 1.7% high- er fertility ... traditional social and economic systems continue, the.

  11. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David Chen, ...

  12. IVF-In Vitro Fertilization.

    Science.gov (United States)

    Kieffer, George H.

    1980-01-01

    Issues surrounding the controversial topic of in vitro fertilization and artificial manipulation of reproduction are discussed. The author examines the moral and ethical implications and presents results of a survey of various religious groups. (SA)

  13. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury ... 2525 info@facingdisability.com SIGN UP FOR OUR NEWSLETTER Your email address * This iframe contains the logic ...

  14. Is fertility falling in Zimbabwe?

    Science.gov (United States)

    Udjo, E O

    1996-01-01

    With an unequalled contraceptive prevalence rate in sub-Saharan Africa, of 43% among currently married women in Zimbabwe, the Central Statistical Office (1989) observed that fertility has declined sharply in recent years. Using data from several surveys on Zimbabwe, especially the birth histories of the Zimbabwe Demographic and Health Survey, this study examines fertility trends in Zimbabwe. The results show that the fertility decline in Zimbabwe is modest and that the decline is concentrated among high order births. Multivariate analysis did not show a statistically significant effect of contraception on fertility, partly because a high proportion of Zimbabwean women in the reproductive age group never use contraception due to prevailing pronatalist attitudes in the country.

  15. Sex and Fertility After SCI

    Medline Plus

    Full Text Available ... Topic Resources Peer Counseling Blog About Media Donate Spinal Cord Injury Medical Expert Videos Topics menu Topics Sex and Fertility After Spinal Cord Injury Adult Injuries Spinal Cord Injury 101 David ...

  16. (ajst) pedological characteristics, general fertility

    African Journals Online (AJOL)

    Administrator

    Key words: Pedological characteristics, fertility, soil classification, benchmark soils, Morogoro. District, Tanzania ... rigorous soil mapping to show their spatial distribution. Although at the ... experience bimodal rainfall pattern characterized by two .... evaluated based on the standards set by EUROCONSULT ... crop growth.

  17. Psychological aspects of male fertility treatment.

    Science.gov (United States)

    Mikkelsen, Alice Toft; Madsen, Svend Aage; Humaidan, Peter

    2013-09-01

    To explore and to identify the possible need for psychological communicative support in men undergoing fertility treatment. Male infertility affects many aspects of a man's life and may cause a life crisis. Although infertility treatment is now commonplace in men, they often feel remote and disconnected from the treatment process. A descriptive survey. A questionnaire with structured and open-ended questions was completed by 210 Danish men undergoing fertility treatment. The questionnaire covered three issues: individual perception of male infertility, gender equality issues, and communication with health professionals in the clinic. Data were collected during 2008. Of the participants, 28% believed that their reduced sperm quality affected their perception of masculinity. 46% stated that equal involvement between partners was a very important element of the treatment; however, 63% said that the health professionals communicated primarily with their female partner. Finally, 62% found that there was a need for a deeper dialogue with the nurses concerning male infertility and 72% lacked information about the psychological consequences of male infertility. In general, participants wanted a more open and balanced dialogue about infertility treatment and the role of the male partner during this process. Infertile men want health professionals to view them on equal terms with their partner. When treating the infertile man, there is a further need to develop more inclusive communication skills. © 2012 Blackwell Publishing Ltd.

  18. Behavior genetic modeling of human fertility

    DEFF Research Database (Denmark)

    Rodgers, J L; Kohler, H P; Kyvik, K O

    2001-01-01

    Behavior genetic designs and analysis can be used to address issues of central importance to demography. We use this methodology to document genetic influence on human fertility. Our data come from Danish twin pairs born from 1953 to 1959, measured on age at first attempt to get pregnant (First......Try) and number of children (NumCh). Behavior genetic models were fitted using structural equation modeling and DF analysis. A consistent medium-level additive genetic influence was found for NumCh, equal across genders; a stronger genetic influence was identified for FirstTry, greater for females than for males....... A bivariate analysis indicated significant shared genetic variance between NumCh and FirstTry....

  19. Fertility Preservation for Children Diagnosed with Cancer

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    Full Text Available ... website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open ... Diagnosed with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation ...

  20. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ... with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for ...

  1. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu Reprotopia_Main_Menu ... Cancer Fertility Preservation for Children Diagnosed with Cancer Patient Pocket Guides Patient Pocket Guides Patient Guides Fertility ...

  2. Method of Euthanasia Influences the Oocyte Fertilization Rate with Fresh Mouse Sperm

    Science.gov (United States)

    Hazzard, Karen C; Watkins-Chow, Dawn E; Garrett, Lisa J

    2014-01-01

    In vitro fertilization (IVF) is used to produce mouse embryos for a variety of reasons. We evaluated the effect of the method of euthanasia on the fertilization rate in 2 different IVF protocols. Oocytes collected from C57BL/6J female mice euthanized by CO2 inhalation or cervical dislocation were used in IVF with fresh sperm from either wild-type or genetically engineered C57BL/6J. Compared with CO2 inhalation, cervical dislocation improved the resulting rate of fertilization by 18% in an IVF method using Cook media and by 13% in an IVF method using methyl-B cyclodextrin and reduced glutathione. The lower fertilization rate due to euthanasia by CO2 inhalation was accompanied by changes in blood pH and body temperature despite efforts to minimize temperature drops. In our hands, euthanasia by cervical dislocation improved fertilization rates and consequently reduced the number of egg-donor mice required. PMID:25650969

  3. Method of euthanasia influences the oocyte fertilization rate with fresh mouse sperm.

    Science.gov (United States)

    Hazzard, Karen C; Watkins-Chow, Dawn E; Garrett, Lisa J

    2014-11-01

    In vitro fertilization (IVF) is used to produce mouse embryos for a variety of reasons. We evaluated the effect of the method of euthanasia on the fertilization rate in 2 different IVF protocols. Oocytes collected from C57BL/6J female mice euthanized by CO2 inhalation or cervical dislocation were used in IVF with fresh sperm from either wild-type or genetically engineered C57BL/6J. Compared with CO2 inhalation, cervical dislocation improved the resulting rate of fertilization by 18% in an IVF method using Cook media and by 13% in an IVF method using methyl-B cyclodextrin and reduced glutathione. The lower fertilization rate due to euthanasia by CO2 inhalation was accompanied by changes in blood pH and body temperature despite efforts to minimize temperature drops. In our hands, euthanasia by cervical dislocation improved fertilization rates and consequently reduced the number of egg-donor mice required.

  4. [Fertility and sterility in domestic animals].

    Science.gov (United States)

    de Kruif, A

    2003-01-01

    For most of the domestic animals the fertility rate is generally very good. If a uniparous female animal is served during the oestrus period by a male with good sperm quality, the pregnancy rate is 60 to 70%. Among the animals that deliver more than one offspring, in many cases the pregnancy rate even reaches more than 90%. Nevertheless, veterinarians are very frequently consulted for fertility problems in individual animals or in cattle or swine herds. The main causes of subfertility are: Insufficient sperm quality An inseminator with insufficient professional knowledge. The majority of the cows, horses and pigs are inseminated artificially (AI). The insemination is not always carried out by experts. Not the right time for insemination. It especially occurs in animals with weak oestrus symptoms. Venereal infections. In earlier days these infections would occur very often. Due to the application of AI, most of these infections have been eradicated. The malfunctioning of the female genital system, which can be caused by various factors, such as cystic ovarian follicles, endometritis and anatomic abnormalities. The research on reproduction which has been going on during the past ten years in the department of Obstetrics, Reproduction and Herd Health, has been mainly concerned with: Embryo transplantation, in vitro fertilisation and ovum pick up The evaluation of sperm quality Improved freezing methods for both sperm and embryo's The development of new insemination techniques The composition of a new diluent for fresh sperm Cystic ovarian follicles in cows Subfertility in different species of animals Next to the above mentioned study fields, the department is also involved in the research into swine fever, respiratory diseases in pigs, antibiotic resistance in pigs and cattle, mastitis and metabolic problems in cattle and salmonella infections in pigs.

  5. Species delimitation in asexual insects of economic importance: The case of black scale (Parasaissetia nigra, a cosmopolitan parthenogenetic pest scale insect.

    Directory of Open Access Journals (Sweden)

    Yen-Po Lin

    Full Text Available Asexual lineages provide a challenge to species delimitation because species concepts either have little biological meaning for them or are arbitrary, since every individual is monophyletic and reproductively isolated from all other individuals. However, recognition and naming of asexual species is important to conservation and economic applications. Some scale insects are widespread and polyphagous pests of plants, and several species have been found to comprise cryptic species complexes. Parasaissetia nigra (Nietner, 1861 (Hemiptera: Coccidae is a parthenogenetic, cosmopolitan and polyphagous pest that feeds on plant species from more than 80 families. Here, we implement multiple approaches to assess the species status of P. nigra, including coalescence-based analyses of mitochondrial and nuclear genes, and ecological niche modelling. Our results indicate that the sampled specimens of P. nigra should be considered to comprise at least two ecotypes (or "species" that are ecologically differentiated, particularly in relation to temperature and moisture. The presence of more than one ecotype under the current concept of P. nigra has implications for biosecurity because the geographic extent of each type is not fully known: some countries may currently have only one of the biotypes. Introduction of additional lineages could expand the geographic extent of damage by the pest in some countries.

  6. Sponge budding is a spatiotemporal morphological patterning process: Insights from synchrotron radiation-based x-ray microtomography into the asexual reproduction of Tethya wilhelma

    Directory of Open Access Journals (Sweden)

    Nickel Michael

    2009-09-01

    Full Text Available Abstract Background Primary agametic-asexual reproduction mechanisms such as budding and fission are present in all non-bilaterian and many bilaterian animal taxa and are likely to be metazoan ground pattern characters. Cnidarians display highly organized and regulated budding processes. In contrast, budding in poriferans was thought to be less specific and related to the general ability of this group to reorganize their tissues. Here we test the hypothesis of morphological pattern formation during sponge budding. Results We investigated the budding process in Tethya wilhelma (Demospongiae by applying 3D morphometrics to high resolution synchrotron radiation-based x-ray microtomography (SR-μCT image data. We followed the morphogenesis of characteristic body structures and identified distinct morphological states which indeed reveal characteristic spatiotemporal morphological patterns in sponge bud development. We discovered the distribution of skeletal elements, canal system and sponge tissue to be based on a sequential series of distinct morphological states. Based on morphometric data we defined four typical bud stages. Once they have reached the final stage buds are released as fully functional juvenile sponges which are morphologically and functionally equivalent to adult specimens. Conclusion Our results demonstrate that budding in demosponges is considerably more highly organized and regulated than previously assumed. Morphological pattern formation in asexual reproduction with underlying genetic regulation seems to have evolved early in metazoans and was likely part of the developmental program of the last common ancestor of all Metazoa (LCAM.

  7. Sponge budding is a spatiotemporal morphological patterning process: Insights from synchrotron radiation-based x-ray microtomography into the asexual reproduction of Tethya wilhelma.

    Science.gov (United States)

    Hammel, Jörg U; Herzen, Julia; Beckmann, Felix; Nickel, Michael

    2009-09-08

    Primary agametic-asexual reproduction mechanisms such as budding and fission are present in all non-bilaterian and many bilaterian animal taxa and are likely to be metazoan ground pattern characters. Cnidarians display highly organized and regulated budding processes. In contrast, budding in poriferans was thought to be less specific and related to the general ability of this group to reorganize their tissues. Here we test the hypothesis of morphological pattern formation during sponge budding. We investigated the budding process in Tethya wilhelma (Demospongiae) by applying 3D morphometrics to high resolution synchrotron radiation-based x-ray microtomography (SR-muCT) image data. We followed the morphogenesis of characteristic body structures and identified distinct morphological states which indeed reveal characteristic spatiotemporal morphological patterns in sponge bud development. We discovered the distribution of skeletal elements, canal system and sponge tissue to be based on a sequential series of distinct morphological states. Based on morphometric data we defined four typical bud stages. Once they have reached the final stage buds are released as fully functional juvenile sponges which are morphologically and functionally equivalent to adult specimens. Our results demonstrate that budding in demosponges is considerably more highly organized and regulated than previously assumed. Morphological pattern formation in asexual reproduction with underlying genetic regulation seems to have evolved early in metazoans and was likely part of the developmental program of the last common ancestor of all Metazoa (LCAM).

  8. New Reproductive Assemblages: Understanding, Managing and ‘Using’ Human In Vitro Fertilization (IVF)

    OpenAIRE

    Just, E.M.

    2009-01-01

    This dissertation is a contribution to the ongoing discussion about the body and in vitro fertilization (IVF), also known as assisted reproduction or technologically enhanced reproduction. With help of empirical research on Dutch and Polish IVF-couples, Edyta Just puts into question the meaning of IVF and discusses the best way of managing the phenomenon and to use it to transform existing ideologies, norms, convictions en discussions on matters such as reproduction, (in)fertility, female/mal...

  9. Uranium and heavy metals in phosphate fertilizers

    International Nuclear Information System (INIS)

    Khater, Ashraf E.M.; King Saud University, Riyadh

    2008-01-01

    Full text: Agricultural applications of chemical fertilizers are a worldwide practice. The specific activity of uranium-238 and heavy metals in phosphate fertilizers depends on the phosphate ore from which the fertilizer produced and on the chemical processing of the ore. Composite phosphate fertilizers samples were collected and the uranium-238 specific activity, in Bq/kg, and As, Cd, Cu, Pb, Se concentration were measured. The annual addition of these elements in soil due to soil fertilization were calculated and discussed. (author)

  10. Fertility and social interaction at the workplace: Does childbearing spread among colleagues?

    Science.gov (United States)

    Pink, Sebastian; Leopold, Thomas; Engelhardt, Henriette

    2014-09-01

    This research investigates whether colleagues' fertility influences women's transitions to parenthood. We draw on Linked-Employer-Employee data (1993-2007) from the German Institute for Employment Research comprising 33,119 female co-workers in 6579 firms. Results from discrete-time hazard models reveal social interaction effects on fertility among women employed in the same firm. In the year after a colleague gave birth, transition rates to first pregnancy double. This effect declines over time and vanishes after two years. Further analyses suggest that the influence of colleagues' fertility is mediated by social learning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. [Fertility of the Yanomami population of Sierra Parima (Amazonas Federal Territory, Venezuela)].

    Science.gov (United States)

    Schkolnik, S

    1983-08-01

    This article presents information on the age structure and level of female fertility obtained on the basis of a sample of the Yanomami population (653 individuals) residing in the Venezuelan margin of Sierra Parima. The population observed is very young, over 50% are less than age 15, and the mean age is 18. The total fertility rate reaches 7.76 children/woman while the age distribution of rates show that fertility begins at a very early age and begins to decrease only after age 30. (author's modified)

  12. Sexual function and fertility issues in cases of exstrophy epispadias complex

    Directory of Open Access Journals (Sweden)

    M S Ansari

    2010-01-01

    Full Text Available In patients with EEC, the issues such as sexuality, sexual function and fertility gain more importance once theses patients advance from puberty to adulthood. The aim of this review is to critically examine the available evidence on these issues. A systemic literature search was performed in Medline over the last 25 years using the key words: Exstrophy, sexual function and pregnancy. Search results were limited to studies of patients with exstrophy published in English literature. A total of 1500 publications were found and subsequently screened by title and when appropriate by abstracts. Of these, 40 publications pertinent to the subject were included for the analysis. The publications were supplemented by an additional 15 publications obtained from their bibliographies. The studies were rated according to the guidelines published by the US department of health and human services. Heterosexuality is usually expressed in both the sexes and most of them have adequate sexual function. Urinary diversion in some series seems to result in better ejaculatory hence fertility outcome in male patients. Recent series have shown equally good results with primary reconstruction. Most of the female patients have normal fertility while male patients have significantly low fertility. Most of the male and female patients with EEC have adequate sexual function. Most of the female patients have normal fertility while most of the male patients have significantly low fertility.

  13. Patriarchy and fertility in Albania

    Directory of Open Access Journals (Sweden)

    Mathias Lerch

    2013-07-01

    Full Text Available BACKGROUND Theories of fertility collapse in the post-socialist era imply a decline in the moral primacy of traditional social institutions. Yet gender inequality actually increased in many countries, and there is a scarcity of empirical evidence for the role played by traditional social institutions in reproductive decision-making. OBJECTIVE We investigate whether patriarchal institutions sustained the fertility levels in Albania. The geography of marriage and family enlargement is related to the importance of patriarchy in kinship organisation and in the public sphere. To account for this spatial relationship we test the evidence for different pathways in patriarchal influence on reproductive decision-making including social effects, socialisation in patriarchal ideals, and the promotion of male fertility. METHODS We reconstruct reproductive histories from the 2001 Census and use data on attitudes and fertility intentions from the Reproductive and Health Survey 2002. Multilevel logistic regressions on marriage and (the intention of higher order births are used. RESULTS A majority of women endorsed patriarchal ideals and fertility transition was less advanced in more patriarchal municipalities. Patriarchal kinship organisation promoted early marriages and high fertility, which is shown to be achieved by social learning among peers and intergenerational social influences respectively, as well as by women's socialisation and a stopping behaviour in childbearing dominated by son-preference. Although gender inequality in the public sphere has also sustained the level of fertility and decreased the risk of marriage, it was not accounted for by these pathways of patriarchal influence. CONCLUSIONS Despite Albania's gradual opening to the world in a period of economic and political crisis, traditional social institutions remain important for family behaviours.

  14. The economics of fertility.

    Science.gov (United States)

    Loraine, J A

    1982-01-01

    The statement that economics and fertility are closely interrelated is a truism. The classical economists--Adam Smith, Thomas Malthus, Karl Marx, John Stuart Mill and John Maynard Keynes appreciated this fact, and their reviews are recounted and their prescience is assessed. Adam Smith (1723-1790) was primarily concerned with the desire of humankind to better his/her material conditions. Although he did not put forward a specific population policy, the tenet of his writing is pronatalist. Economic advantages would accrue to parents by the production of many children. Yet, underneath Smith's optimism, there was an apocalyptic vision of the distant future, i.e., the "steady state" when resources would be depleted or near exhaustion, when capital accumulation would have ceased, and living standards would be dropping vertiginously. In his 1st "Essay on Population" Malthus maintained that "the power of population is infinitely greater than the power of the earth to produce subsistence of men." Malthus can be complimented on his prescience. There is little question that the planet of today is grossly overpopulated and that a great gulf exists between numbers of people and their aspirations and the resources which the earth can provide for them. Malthus was particularly concerned about the population food dilemma, and that is still much in evidence in 1982. 2 concomitants of overpopulation--excessive urbanization and joblessness--could not be foreseen by Malthus. Marx did not deny the basic tenet promulgated by Malthus but to him this was simply an artifact of capitalist society which required "enormous reserves of proletarians" in order to maintain its odius system. Officially Communist governments remain in a Marxist straitjacket regarding the population issue. Mills approach was strongly antinatalist; he saw little need for an increase in human numbers. Mills was concerned that because of unlimited population growth and wealth the earth would lose much of its

  15. Can public policies sustain fertility in the Nordic countries?: Lessons from the past and questions for the future

    Directory of Open Access Journals (Sweden)

    Marit Rønsen

    2010-03-01

    Full Text Available The collective evidence of past research indicates that Nordic social welfare policies have had positive impacts on fertility. Yet, some patterns cause concern. One concern is that the good recuperation at cohort level partly is explained by relatively high fertility levels among women educated for female-dominated jobs with extensive part-time work. One may therefore question whether the present development is compatible with gender equality. Another concern is a more socially selective entry into fatherhood. Based on updated analyses of female as well as male fertility trends in Norway we address these issues, focussing especially on associations with educational level and field.

  16. Mutation in SUMO E3 ligase, SIZ1, disrupts the mature female gametophyte in Arabidopsis

    KAUST Repository

    Ling, Yu; Zhang, Chunyu; Chen, Tong; Hao, Huaiqing; Liu, Peng; Bressan, Ray A.; Hasegawa, Paul M.; Jin, Jing Bo; Lin, Jinxing

    2012-01-01

    Female gametophyte is the multicellular haploid structure that can produce embryo and endosperm after fertilization, which has become an attractive model system for investigating molecular mechanisms in nuclei migration, cell specification, cell

  17. Antioxidants for female subfertility.

    Science.gov (United States)

    Showell, Marian G; Mackenzie-Proctor, Rebecca; Jordan, Vanessa; Hart, Roger J

    2017-07-28

    A couple may be considered to have fertility problems if they have been trying to conceive for over a year with no success. This may affect up to a quarter of all couples planning a child. It is estimated that for 40% to 50% of couples, subfertility may result from factors affecting women. Antioxidants are thought to reduce the oxidative stress brought on by these conditions. Currently, limited evidence suggests that antioxidants improve fertility, and trials have explored this area with varied results. This review assesses the evidence for the effectiveness of different antioxidants in female subfertility. To determine whether supplementary oral antioxidants compared with placebo, no treatment/standard treatment or another antioxidant improve fertility outcomes for subfertile women. We searched the following databases (from their inception to September 2016) with no language or date restriction: Cochrane Gynaecology and Fertility Group (CGFG) specialised register, the Cochrane Central Register of Studies (CENTRAL CRSO), MEDLINE, Embase, PsycINFO, CINAHL and AMED. We checked reference lists of appropriate studies and searched for ongoing trials in the clinical trials registers. We included randomised controlled trials (RCTs) that compared any type, dose or combination of oral antioxidant supplement with placebo, no treatment or treatment with another antioxidant, among women attending a reproductive clinic. We excluded trials comparing antioxidants with fertility drugs alone and trials that only included fertile women attending a fertility clinic because of male partner infertility. Two review authors independently selected eligible studies, extracted the data and assessed the risk of bias of the included studies. The primary review outcome was live birth; secondary outcomes included clinical pregnancy rates and adverse events. We pooled studies using a fixed-effect model, and calculated odds ratios (ORs) with 95% confidence intervals (CIs) for the dichotomous

  18. Male fertility in cystic fibrosis.

    LENUS (Irish Health Repository)

    Chotirmall, S H

    2011-04-05

    Infertility rates among males with cystic fibrosis (CF) approximate 97%. No information is currently available within Ireland determining an understanding of fertility issues and the best methods of information provision to this specialized group. This study aimed to determine understanding and preferred approaches to information provision on fertility issues to Irish CF males. A Descriptive Study utilizing prospective coded questionnaires was mailed to a male CF cohort (n=50). Sections included demographics, fertility knowledge & investigation. Response rate was 16\\/50 (32%). All were aware that CF affected their fertility. More than two-thirds (n=11) were able to provide explanations whilst only one-third (n=5) provided the correct explanation. Significant numbers stated thoughts of marriage and a future family. Half have discussed fertility with a healthcare professional (HCP). Mean age of discussion was 21.9 years. One third preferred an earlier discussion. The commonest first source for information was written material which was also the preferred source. Three-quarters requested further information preferring again, written material. Significant gaps in sex education of Irish CF males exist. Discussion should be initiated by HCPs and centre-directed written material devised to address deficiencies.

  19. Obesity: modern man's fertility nemesis.

    Science.gov (United States)

    Cabler, Stephanie; Agarwal, Ashok; Flint, Margot; du Plessis, Stefan S

    2010-07-01

    The obesity pandemic has grown to concerning proportions in recent years, not only in the Western World, but in developing countries as well. The corresponding decrease in male fertility and fecundity may be explained in parallel to obesity, and obesity should be considered as an etiology of male fertility. Studies show that obesity contributes to infertility by reducing semen quality, changing sperm proteomes, contributing to erectile dysfunction, and inducing other physical problems related to obesity. Mechanisms for explaining the effect of obesity on male infertility include abnormal reproductive hormone levels, an increased release of adipose-derived hormones and adipokines associated with obesity, and other physical problems including sleep apnea and increased scrotal temperatures. Recently, genetic factors and markers for an obesity-related infertility have been discovered and may explain the difference between fertile obese and infertile obese men. Treatments are available for not only infertility related to obesity, but also as a treatment for the other comorbidities arising from obesity. Natural weight loss, as well as bariatric surgery are options for obese patients and have shown promising results in restoring fertility and normal hormonal profiles. Therapeutic interventions including aromatase inhibitors, exogenous testosterone replacement therapy and maintenance and regulation of adipose-derived hormones, particularly leptin, may also be able to restore fertility in obese males. Because of the relative unawareness and lack of research in this area, controlled studies should be undertaken and more focus should be given to obesity as an etiolgy of male infertility.

  20. Innovative fertility preservation strategies and programs for young adults with cancer

    Directory of Open Access Journals (Sweden)

    Johnson RH

    2016-01-01

    Full Text Available Rebecca H Johnson Division of Pediatric Hematology/Oncology, Department of Pediatrics, Mary Bridge Hospital, MultiCare Health System, Tacoma, WA, USA Abstract: Preservation of fertility is a key issue for young adults newly diagnosed with cancer. Up to 90% of cancer patients under the age of 45 are at risk for fertility impairment following cancer therapy. Cancer patients who are not offered fertility preservation (FP and those who become infertile following therapy may experience long-term psychosocial distress. This review summarizes the numerous effective strategies for preserving fertility, including sperm banking, electroejaculation, and testicular sperm extraction in males and cryopreservation of embryos or oocytes in females. This paper also highlights novel methods currently in development, such as gonadal tissue cryopreservation and in vitro maturation of gametes. In women, anti-Mullerian hormone is emerging as an accurate marker of ovarian reserve, and the use of gonadotropin releasing hormone analogs to protect fertility is increasingly well validated. Although national guidelines mandate FP counseling and referral prior to the start of cancer therapy for patients with reproductive potential, only a minority of young cancer patients in the USA currently take steps to preserve fertility prior to the start of therapy. Some cancer centers across the USA are developing institutional strategies to support FP, resulting in increased utilization of fertility services by newly diagnosed cancer patients. Keywords: young adult, cancer, fertility preservation, program, oocyte, sperm

  1. Genetic Compatibility Underlies Benefits of Mate Choice in an External Fertilizer.

    Science.gov (United States)

    Aguirre, J David; Blows, Mark W; Marshall, Dustin J

    2016-05-01

    Mate choice is a common feature of sexually reproducing species. In sessile or sedentary external fertilizers, however, direct interactions between reproductive partners are minimal, and instead mate recognition and choice must occur at the level of gametes. It is common for some sperm and egg combinations to have higher fertilization success than others, but it remains unclear whether differences in fertilization reflect gamete-level mate choice (GMC) for paternal quality or parental compatibility. Here, we examine the mechanisms underlying GMC in an externally fertilizing ascidian. A manipulative mate-choice assay confirmed that offspring viability was greater in clutches where we allowed GMC than in clutches where we precluded GMC. A complementary quantitative genetic experiment then revealed that paternal quality effects were generally weaker than parental compatibility effects, particularly for the trait combination underlying the benefits of GMC. Overall, our data suggest that gametes that are more compatible at fertilization produce more viable offspring than gametes that are less compatible at fertilization. Therefore, although the regalia we typically associate with sexual selection are absent in external fertilizers, mechanisms that allow females to bias fertilization in favor of some males over others produce significant fitness benefits in organisms reproducing via the ancestral strategy.

  2. Female in-nest chatter song increases predation

    OpenAIRE

    Kleindorfer, Sonia; Evans, Christine; Mahr, Katharina

    2016-01-01

    Female song is an ancestral trait in songbirds, yet extant females generally sing less than males. Here, we examine sex differences in the predation cost of singing behaviour. The superb fairy-wren (Malurus cyaneus) is a Southern Hemisphere songbird; males and females provision the brood and produce solo song year-round. Both sexes had higher song rate during the fertile period and lower song rate during incubation and chick feeding. Females were more likely than males to sing close to or ins...

  3. Fertility effects of cancer treatment.

    Science.gov (United States)

    Marsden, Donald E; Hacker, Neville

    2003-01-01

    Cancer sufferers are a subfertile group, and most treatments have the potential to adversely affect gonadal function. As cancer treatment becomes more effective and survival rates improve there are more cancer survivors in the reproductive age group for whom parenting is an important consideration. This article outlines the effects on fertility of cancer treatments and techniques to minimise the risk of infertility. The overall prospects for younger cancer sufferers to either retain their fertility or have genetic offspring is now better than ever before, due to advances in assisted reproductive technology, the appropriate use of fertility sparing surgery and other techniques to reduce the toxicity of therapy on the reproductive organs. These advances raise new moral and ethical concerns that must be considered before advising cancer sufferers of the options for preserving reproductive capacity.

  4. Crystallographic properties of fertilizer compounds

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, A.W.; Dillard, E.F.; Thrasher, R.D.; Waerstad, K.R.; Hunter, S.R.; Kohler, J.J.; Scheib, R.M.

    1991-02-01

    This bulletin is a compilation of crystallographic data collected at NFERC on 450 fertilizer-related compounds. In TVA's fertilizer R and D program, petrographic examination, XRD, and infrared spectroscopy are combined with conventional chemical analysis methods in identifying the individual compounds that occur in fertilizer materials. This handbook brings together the results of these characterization studies and supplemental crystallographic data from the literature. It is in one-compound-per-page, loose-leaf format, ordered alphabetically by IUPAC name. Indexes provided include IUPAC name, formula, group, alternate formula, synonyms, x-ray data, optical data. Tables are given for solids, compounds in commercial MAP and DAP, and matrix materials in phosphate rock.

  5. Effects of gamma radiation on codling moth (Cydia pomonella, Lepidoptera: Tortricidae) fertility and reproductive behaviour

    International Nuclear Information System (INIS)

    Mansour, M.

    2002-01-01

    Studies were conducted with codling moth, Cydia pomonella (L.), to examine the effects of gamma radiation on fertility and reproductive behaviour. Data accumulated during these studies showed that egg production and hatch decreased with increasing radiation dose. Females were more sensitive to radiation treatment than were males. A dose of 150 Gy caused 100% sterility in females and significantly reduced fecundity, and a dose of 350 Gy reduced male fertility to less than 1%. Radiation dosages up to 400 Gy had no adverse effect on male longevity or competitiveness in cages using laboratory reared moths. However, males exposed to a dose of 350 or 400 Gy mated fewer times than unirradiated males. (author)

  6. Marijuana, the Endocannabinoid System and the Female Reproductive System.

    Science.gov (United States)

    Brents, Lisa K

    2016-06-01

    Marijuana use among women is highly prevalent, but the societal conversation on marijuana rarely focuses on how marijuana affects female reproduction and endocrinology. This article reviews the current scientific literature regarding marijuana use and hypothalamic-pituitary-ovarian (HPO) axis regulation, ovarian hormone production, the menstrual cycle, and fertility. Evidence suggests that marijuana can reduce female fertility by disrupting hypothalamic release of gonadotropin releasing hormone (GnRH), leading to reduced estrogen and progesterone production and anovulatory menstrual cycles. Tolerance to these effects has been shown in rhesus monkeys, but the effects of chronic marijuana use on human female reproduction are largely unknown. Marijuana-induced analgesia, drug reinforcement properties, tolerance, and dependence are influenced by ovarian hormones, with estrogen generally increasing and progesterone decreasing sensitivity to marijuana. Carefully controlled regulation of the Endocannabinoid System (ECS) is required for successful reproduction, and the exogenous cannabinoids in marijuana may disrupt the delicate balance of the ECS in the female reproductive system.

  7. Sexuality and fertility outcomes after hand sewn versus stapled ileal pouch anal anastomosis for ulcerative colitis.

    Science.gov (United States)

    Harnoy, Yann; Desfourneaux, Véronique; Bouguen, Guillaume; Rayar, Michel; Meunier, Bernard; Siproudhis, Laurent; Boudjema, Karim; Sulpice, Laurent

    2016-01-01

    Ileal pouch anal anastomosis (IPAA) may alter sexuality and fertility in women. The laparoscopic approach seems to reduce infertility rates in women after IPAA. However, the impact of hand sewn versus stapled IPAA on sexuality and fertility has never been assessed in patients with ulcerative colitis (UC). The objective of this study was to analyze the impact of the IPAA technique on sexuality and fertility in UC. All UC patients who underwent an IPAA between May 1996 and April 2011 were included. The patients answered mailed questionnaires including sexuality validated questionnaires and fertility questionnaires. The risk factors of sexual dysfunction were explored. A total of 135 patients were included. Eighty-eight patients (65%) answered the questionnaires. Their mean age and follow-up were 37.2 ± 13.4 y and 109.7 ± 57.5 mo. The rates of female and male sexual dysfunction were 50% and 29%, respectively. Intestinal transit disorders were identified as risk factors in both men and women and anastomotic stricture in women sexual dysfunction, in univariate analyses. The IPAA technique did not impact sexual function in women but there was a trend for less erectile dysfunction after hand sewn IPAA (16.7% versus 44.4%). The fertility rate was 47% in women and 75% in men, with a trend for a better fertility in women after hand sewn IPAA (P = 0.07). In this preliminary study, the hand sewn or stapled IPAA technique did not impact the sexuality or fertility outcomes of UC patients, but there was a trend for better female fertility and male erectile function after hand sewn IPAA. Intestinal transit disorders contributed to male and female sexual dysfunction after IPAA. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Smoke, alcohol and drug addiction and male fertility.

    Science.gov (United States)

    Sansone, Andrea; Di Dato, Carla; de Angelis, Cristina; Menafra, Davide; Pozza, Carlotta; Pivonello, Rosario; Isidori, Andrea; Gianfrilli, Daniele

    2018-01-15

    In recent decades, the decline in human fertility has become increasingly more worrying: while therapeutic interventions might help, they are vexing for the couple and often burdened with high failure rates and costs. Prevention is the most successful approach to fertility disorders in males and females alike. We performed a literature review on three of the most common unhealthy habits - tobacco, alcohol and drug addiction - and their reported effects on male fertility. Tobacco smoking is remarkably common in most first-world countries; despite a progressive decline in the US, recent reports suggest a prevalence of more than 30% in subjects of reproductive age - a disturbing perspective, given the well-known ill-effects on reproductive and sexual function as well as general health. Alcohol consumption is often considered socially acceptable, but its negative effects on gonadal function have been consistently reported in the last 30 years. Several studies have reported a variety of negative effects on male fertility following drug abuse - a worrying phenomenon, as illicit drug consumption is on the rise, most notably in younger subjects. While evidence in these regards is still far from solid, mostly as a result of several confounding factors, it is safe to assume that cessation of tobacco smoking, alcohol consumption and recreational drug addiction might represent the best course of action for any couple trying to achieve pregnancy.

  9. Lifestyle factors and reproductive health: taking control of your fertility.

    Science.gov (United States)

    Sharma, Rakesh; Biedenharn, Kelly R; Fedor, Jennifer M; Agarwal, Ashok

    2013-07-16

    Approximately 10 to 15% of couples are impacted by infertility. Recently, the pivotal role that lifestyle factors play in the development of infertility has generated a considerable amount of interest. Lifestyle factors are the modifiable habits and ways of life that can greatly influence overall health and well-being, including fertility. Many lifestyle factors such as the age at which to start a family, nutrition, weight, exercise, psychological stress, environmental and occupational exposures, and others can have substantial effects on fertility; lifestyle factors such as cigarette smoking, illicit drug use, and alcohol and caffeine consumption can negatively influence fertility while others such as preventative care may be beneficial. The present literature review encompasses multiple lifestyle factors and places infertility in context for the couple by focusing on both males and females; it aims to identify the roles that lifestyle factors play in determining reproductive status. The growing interest and amount of research in this field have made it evident that lifestyle factors have a significant impact on fertility.

  10. Cohort fertility and educational expansion in the Czech Republic during the 20th century

    Directory of Open Access Journals (Sweden)

    Krystof Zeman

    2018-05-01

    Full Text Available Background: During the 20th century the Czech Republic went through profound changes in female employment, gender roles, population and family policies, and public childcare. The educational structure of the female population changed tremendously. At the same time, completed cohort fertility fluctuated between 1.8 and 2.2 children per woman. Objective: This article analyses the changes in the level of completed cohort fertility by education, during educational expansion in the Czech population under the economic, cultural, and institutional background of the state socialist regime, and after its breakdown. Methods: The changes in the level of completed cohort fertility by education are analysed by means of decomposition, complemented by the analysis of parity composition. Results: During the 20th century, education-specific completed cohort fertility increased, rather than declined. Fertility levels converged upwards, contributing to high uniformity within educational categories. The overall changes in fertility levels were driven by changes in the educational structure. These trends resulted in the dominance of the two-child family, while large families were disappearing and childlessness dropped to the biological minimum. Conclusions: An egalitarian economic system with traditional family-friendly policies, in combination with a family-unfriendly labour market, developed into a male breadwinner model of low gender equity. Future family policies should focus on the reconciliation of work and family. Contribution: The study contributes to the discussion on links between education and fertility, adding a new picture to the mosaic of country-level analyses. The Czech Republic is an example of a country with high educational homogeneity of fertility behaviour where the education-specific levels of fertility converged upwards.

  11. Child survival and changing fertility patterns in Pakistan.

    Science.gov (United States)

    Sathar, Z A

    1992-01-01

    Pakistan is a country with high fertility and high infant and child mortality, and declines in total mortality and substantial development initiatives. The discussion considers whether fertility patterns in Pakistan can be related to changes in child mortality, and whether current and future changes in fertility influence child survival favorably. Omran's study linked large family size to child survival. Resources, which are divided, become more important deficits in households below the poverty line: a situation common in Pakistan. High fertility is associated with short birth intervals, which are related to higher infant and child mortality. In Pakistan, the spacing and mortality link was found among both poverty and higher socioeconomic households. There is some support for the notion that it is birth weight and general health that are linked to survival rather than competition for resources. Other studies link the maternal age at birth and birth order with child mortality (Alam and Cleland). Trussel argues for limiting births in high risk ages of under 20 years and over 35 years. The exact casual link is not well documented. Institutional and community factors are also considered important in influencing child survival: sanitation, potable water, access to roads, electricity, health and family planning services, and sewage. Young infants are more vulnerable to these factors. Bangladesh and some Indian states have shown that population programs and raising per captia incomes are necessary to fertility decline. In India, female autonomy, access to education, and more equal income distribution were considered more important than economic development to child survival. In Pakistan, Sathar and Kazi have linked at least 2 years of elementary, maternal education with reductions in child mortality. The pervasiveness of female illiteracy hinders the chances of child survival. Sex preferences also impact on female children. The probably impacts of declines in breast

  12. Soil Fertility Status on Organic Paddy Experiment

    Directory of Open Access Journals (Sweden)

    Mujiyo

    2015-07-01

    Full Text Available The study aims to determine fertility status of the soil after organic paddy experiments using kinds and doses of organic fertilizers. Experiment was conducted at greenhouse laboratory in Faculty of Agriculture Sebelas Maret University Surakarta. Experimental design used completely randomized design with 9 kinds of treatment was replicated 3 times. Experiments were the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations that are based on fulfilling nutrient requirements of 120 kg N ha-1. Result shows that the use of cow manure, Azolla fertilizers and Azolla inoculum had no effect on changes of soil fertility status. Soil fertility status was not significantly correlated with cow manure (0,16ns, Azolla fertilizer (0,26ns and Azolla inoculum (0,16ns. Average of final soil fertility status included fertile category, which was similar as the initial soil fertility status. Average of final soil properties of treatment but nevertheless was relatively higher than in no treatment, indicating the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations had greater impact to soil properties. Cow manure despite increased available K2O and dry grain, but it did not significantly increase the soil fertility status from fertile to very fertile. This was presumably due to the relatively short experiment period, only one planting season had not given significant effect to soil properties. Implication of this study is the use of cow manure, Azolla fertilizer, Azolla inoculum and its combinations although did not increase the soil fertility status but could maintain soil fertility status as the initial conditions before planting.

  13. Normal Female Reproductive Anatomy

    Science.gov (United States)

    ... historical Searches are case-insensitive Reproductive System, Female, Anatomy Add to My Pictures View /Download : Small: 720x756 ... Large: 3000x3150 View Download Title: Reproductive System, Female, Anatomy Description: Anatomy of the female reproductive system; drawing ...

  14. Sildenafil citrate (Viagra) impairs fertilization and early embryo development in mice.

    Science.gov (United States)

    Glenn, David R J; McClure, Neil; Cosby, S Louise; Stevenson, Michael; Lewis, Sheena E M

    2009-03-01

    To determine the effects of sildenafil citrate, a cyclic monophosphate-specific type 5 phosphodiesterase inhibitor known to affect sperm function, on fertilization and early embryo cleavage. This acute mammal study included male and female mice assigned randomly, the females sacrificed after mating and their oocytes/embryos evaluated at four time periods after treatment. Academic research environment. Male and female CBAB(6) mice. Female mice were injected intraperitoneally with 5 IU gonadotropin (hCG) to stimulate follicular growth and induce ovulation. They were each caged with a male that had been gavaged with sildenafil citrate (0.06 mg/0.05 mL) and allowed to mate. After 12, 36, 60, and 84 h, females were killed, their oviducts were dissected out, and retrieved embryos were assessed for blastomere number and quality. Fertilization rates and numbers of embryos were evaluated after treatment. Fertilization rates (day 1) were markedly reduced (-33%) in matings where the male had taken sildenafil citrate. Over days 2-4, the numbers of embryos developing in the treated group were significantly fewer than in the control group. There was also a trend for impaired cleavage rates within those embryos, although this did not reach significance. The impairments to fertility caused by sildenafil citrate have important implications for infertility centers and for couples who are using this drug precoitally while attempting to conceive.

  15. Flow cytometric readout based on Mitotracker Red CMXRos staining of live asexual blood stage malarial parasites reliably assesses antibody dependent cellular inhibition

    DEFF Research Database (Denmark)

    Jogdand, Prajakta S; Singh, Susheel K; Christiansen, Michael

    2012-01-01

    asynchronous and tightly synchronized asexual blood stage cultures of Plasmodium falciparum were stained with CMXRos and subjected to detection by flow cytometry and fluorescence microscopy. The parasite counts obtained by flow cytometry were compared to standard microscopic counts obtained through examination......ABSTRACT: BACKGROUND: Functional in vitro assays could provide insights into the efficacy of malaria vaccine candidates. For estimating the anti-parasite effect induced by a vaccine candidate, an accurate determination of live parasite count is an essential component of most in vitro bioassays....... Although traditionally parasites are counted microscopically, a faster, more accurate and less subjective method for counting parasites is desirable. In this study mitochondrial dye (Mitotracker Red CMXRos) was used for obtaining reliable live parasite counts through flow cytometry. METHODS: Both...

  16. Dual stage synthesis and crucial role of cytoadherence-linked asexual gene 9 in the surface expression of malaria parasite var proteins

    DEFF Research Database (Denmark)

    Goel, Suchi; Valiyaveettil, Manojkumar; Achur, Rajeshwara N

    2010-01-01

    adherence. However, how CLAG9 influences this process remains unknown. In this study, we show that CLAG9 interacts with VAR2CSA, a PfEMP1 that mediates IRBC adherence to chondroitin 4-sulfate in the placenta. Importantly, our results show that the adherent parasites synthesize CLAG9 at two stages--the early......Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family members mediate the adherence of parasite-infected red blood cells (IRBCs) to various host receptors. A previous study has shown that the parasite protein, cytoadherence-linked asexual gene 9 (CLAG9), is also essential for IRBC...... within the parasite. Based on these findings, we propose that CLAG9 plays a critical role in the trafficking of PfEMP1s onto the IRBC surface. These results have important implications for the development of therapeutics for cerebral, placental, and other cytoadherence-associated malaria illnesses....

  17. Soil fertility and plant nutrition

    International Nuclear Information System (INIS)

    Menzel, R.G.; Smith, S.J.

    1984-01-01

    The applications of isotopic and related techniques, including autoradiography, radiation absorption, radiation scattering and activation analysis, in investigations on soil fertility and plant nutrition are discussed. The unique information that can be obtained with isotopes and radiation techniques is indicated. The advantages and disadvantages of these techniques are discussed in relation to other methods of obtaining similar information. (U.K.)

  18. Plant fertilization: maximizing reproductive success.

    Science.gov (United States)

    Dresselhaus, Thomas; Sprunck, Stefanie

    2012-06-19

    Sperm competition does not occur in flowering plants as typically only a single pair of sperm cells is delivered for double fertilization. Two recent reports show that plants are capable of avoiding reproductive failure when defective sperm cells are released. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Strong families and declining fertility

    NARCIS (Netherlands)

    Hilevych, Yuliya

    2016-01-01

    This dissertation focuses on the role of family and social relationships in individuals’ reproductive careers during the fertility decline in Soviet Ukraine from around 1950 to 1975. These three decades after the Second World War signified the end of the First Demographic Transition in Ukraine

  20. Global fertility and population trends.

    Science.gov (United States)

    Bongaarts, John

    2015-01-01

    Over the past several decades, the world and most countries have undergone unprecedented demographic change. The most obvious example of this change is the rise in human numbers, and there are also important trends in fertility, family structure, mortality, migration, urbanization, and population aging. This paper summarizes past trends and projections in fertility and population. After reaching 2.5 billion in 1950, the world population grew rapidly to 7.2 billion in 2013 and the projections expect this total to be 10.9 billion by 2100. World regions differ widely in their demographic trends, with rapid population growth and high fertility continuing in the poorest countries, particularly in sub-Saharan Africa, while population decline, population aging, and very low fertility are now a key concern in many developed countries. These trends have important implications for human welfare and are of interest to policy makers. The conclusion comments briefly on policy options to address these adverse trends. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.