Budak, Erdal; Fernández Sánchez, Manuel; Bellver, José; Cerveró, Ana; Simón, Carlos; Pellicer, Antonio
2006-06-01
To summarize the effects of novel hormones (leptin, ghrelin, adiponectin, resistin, and PYY3-36) secreted from adipose tissue and the gastrointestinal tract that have been discovered to exert different effects on several reproductive functions, such as the hypothalamic-pituitary-gonadal axis, embryo development, implantation physiology, and clinically relevant conditions. A MEDLINE computer search was performed to identify relevant articles. Leptin and ghrelin exert important roles on body weight regulation, eating behavior, and reproduction, acting on the central nervous system and target reproductive organs. As a marker of adequate nutritional stores, these hormones may act on the central nervous system to initiate the complex process of puberty and maintain normal reproductive function. In addition, leptin and ghrelin and their receptors are involved in reproductive events such as gonadal function, embryo development, and embryo-endometrial interaction. Leptin and ghrelin and other adipose tissue-secreted hormones have significant effects on reproduction. Acting through the brain, these hormones may serve as links between adipose tissue and the reproductive system to supply and regulate energy needs for normal reproduction and pregnancy. Future studies are needed to further clarify the role of these hormones in reproductive events and other related gynecological conditions.
Color reproduction for advanced manufacture of soft tissue prostheses.
Xiao, Kaida; Zardawi, Faraedon; van Noort, Richard; Yates, Julian M
2013-11-01
The objectives of this study were to develop a color reproduction system in advanced manufacture technology for accurate and automatic processing of soft tissue prostheses. The manufacturing protocol was defined to effectively and consistently produce soft tissue prostheses using a 3D printing system. Within this protocol printer color profiles were developed using a number of mathematical models for the proposed 3D color printing system based on 240 training colors. On this basis, the color reproduction system was established and their system errors including accuracy of color reproduction, performance of color repeatability and color gamut were evaluated using 14 known human skin shades. The printer color profile developed using the third-order polynomial regression based on least-square fitting provided the best model performance. The results demonstrated that by using the proposed color reproduction system, 14 different skin colors could be reproduced and excellent color reproduction performance achieved. Evaluation of the system's color repeatability revealed a demonstrable system error and this highlighted the need for regular evaluation. The color gamut for the proposed 3D printing system was simulated and it was demonstrated that the vast majority of skin colors can be reproduced with the exception of extreme dark or light skin color shades. This study demonstrated that the proposed color reproduction system can be effectively used to reproduce a range of human skin colors for application in advanced manufacture of soft tissue prostheses. Copyright © 2013 Elsevier Ltd. All rights reserved.
Fetal programming of sexual development and reproductive function.
Zambrano, Elena; Guzmán, Carolina; Rodríguez-González, Guadalupe L; Durand-Carbajal, Marta; Nathanielsz, Peter W
2014-01-25
The recent growth of interest in developmental programming of physiological systems has generally focused on the cardiovascular system (especially hypertension) and predisposition to metabolic dysfunction (mainly obesity and diabetes). However, it is now clear that the full range of altered offspring phenotypes includes impaired reproductive function. In rats, sheep and nonhuman primates, reproductive capacity is altered by challenges experienced during critical periods of development. This review will examine available experimental evidence across commonly studied experimental species for developmental programming of female and male reproductive function throughout an individual's life-course. It is necessary to consider events that occur during fetal development, early neonatal life and prior to and during puberty, during active reproductive life and aging as reproductive performance declines. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
CRITICAL WINDOWS FOR REPRODUCTIVE HEALTH IN CHILDREN AND ADOLESCENTS
This workgroup report addresses the central question: what are the critical windows during development (pre-conception through puberty) when exposure to xenobiotics may have the greatest adverse impact on subsequent reproductive health. The reproductive system develops in stages...
Mathematical modeling of the female reproductive system: from oocyte to delivery.
Clark, Alys R; Kruger, Jennifer A
2017-01-01
From ovulation to delivery, and through the menstrual cycle, the female reproductive system undergoes many dynamic changes to provide an optimal environment for the embryo to implant, and to develop successfully. It is difficult ethically and practically to observe the system over the timescales involved in growth and development (often hours to days). Even in carefully monitored conditions clinicians and biologists can only see snapshots of the development process. Mathematical models are emerging as a key means to supplement our knowledge of the reproductive process, and to tease apart complexity in the reproductive system. These models have been used successfully to test existing hypotheses regarding the mechanisms of female infertility and pathological fetal development, and also to provide new experimentally testable hypotheses regarding the process of development. This new knowledge has allowed for improvements in assisted reproductive technologies and is moving toward translation to clinical practice via multiscale assessments of the dynamics of ovulation, development in pregnancy, and the timing and mechanics of delivery. WIREs Syst Biol Med 2017, 9:e1353. doi: 10.1002/wsbm.1353 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.
Reproductive Medicine in Amphibians.
Chai, Norin
2017-05-01
Reproduction of amphibians includes ovulation, spermiation, fertilization, oviposition, larval stage and development, and metamorphosis. A problem at any stage could lead to reproductive failure. To stimulate reproduction, environmental conditions must be arranged to simulate changes in natural habits. Reproductive life history is well documented in amphibians; a thorough knowledge of this subject will aid the practitioner in diagnosis and treatment. Technologies for artificial reproduction are developing rapidly, and some protocols may be transferable to privately kept or endangered species. Reproductive tract disorders are rarely described; no bacterial or viral diseases are known that specifically target the amphibian reproductive system. Copyright © 2016 Elsevier Inc. All rights reserved.
The role of the leptin in reproduction.
Cervero, Ana; Domínguez, Francisco; Horcajadas, José A; Quiñonero, Alicia; Pellicer, Antonio; Simón, Carlos
2006-06-01
Since its discovery in 1994, leptin has appeared to be a pleiotrophic hormone, governing energy homeostasis and affecting many tissues in the body. Numerous pieces of evidence have accumulated showing that leptin potentially plays an important role in the control of the reproductive function. This review presents the major concepts for the role of leptin in the modulation of reproductive function. As a marker of the nutritional status, leptin affects the hypothalamo-pituitary-gonadal axis, regulating gonadotrophin-releasing hormone and luteinising hormone secretion, and appears to be a permissive factor in the onset of the puberty. This protein and its receptor have been found in the reproductive tissues, indicating that this system could be also implicated in several processes such as embryo development, implantation and pregnancy. Moreover, disorders of the leptin system have been related to some reproductive pathologies such as pre-eclampsia and polycystic ovary syndrome. However, controversy surrounds several aspects of the action of leptin in reproduction that require a deeper investigation of this system. Results to date suggest that this system could be implicated in important reproductive processes such as embryonic development and implantation. Moreover, understanding the role of leptin might be useful for new treatments in reproductive pathologies.
Normal development of the female reproductive system
The embryonic development of the female reproductive system involves a progression of events that is conserved across vertebrate species. The early gonad progresses from a form that is undifferentiated in both genotypic males and females. Rudimentary male (Wolffian) and female (M...
... sexual intercourse. The male reproductive system also produces sex hormones, which help a boy develop into a sexually mature man during puberty . ... Understanding Early Sexual Development Questions and Answers About Sex Talking to Your ... Torsion For Boys: Trouble "Down There" Boys and Puberty All About ...
This workgroup report addresses the central question: what are the critical windows during development (pre-conception through puberty) when exposure to xenobiotics may have the greatest adverse impact on subsequent reproductive health. The reproductive system develops in stages...
Thyroid hormone actions on male reproductive system of teleost fish.
Tovo-Neto, Aldo; da Silva Rodrigues, Maira; Habibi, Hamid R; Nóbrega, Rafael Henrique
2018-04-17
Thyroid hormones (THs) play important roles in the regulation of many biological processes of vertebrates, such as growth, metabolism, morphogenesis and reproduction. An increasing number of studies have been focused on the involvement of THs in the male reproductive system of vertebrates, in particular of fish. Therefore, this mini-review aims to summarize the main findings on THs role in male reproductive system of fish, focusing on sex differentiation, testicular development and spermatogenesis. The existing data in the literature have demonstrated that THs exert their roles at the different levels of the hypothalamic-pituitary-gonadal (HPG) axis. In general a positive correlation has been shown between THs and fish reproductive status; where THs are associated with testicular development, growth and maturation. Recently, the molecular mechanisms underlying the role of THs in spermatogenesis have been unraveled in zebrafish testis. THs promote germ cell proliferation and differentiation by increasing a stimulatory growth factor of spermatogenesis produced by Sertoli cells. In addition, THs enhanced the gonadotropin-induced androgen release in zebrafish testis. Next to their functions in the adult testis, THs are involved in the gonadal sex differentiation through modulating sex-related gene expression, and testicular development via regulation of Sertoli cell proliferation. In conclusion, this mini-review showed that THs modulate the male reproductive system during the different life stages of fish. The physiological and molecular mechanisms showed a link between the thyroid and reproduction, suggesting a possibly co-evolution and interdependence of these two systems. Copyright © 2018 Elsevier Inc. All rights reserved.
Chang, Chawnshang; Lee, Soo Ok; Wang, Ruey-Sheng; Yeh, Shuyuan; Chang, Ta-Min
2013-01-01
ABSTRACT Androgens/androgen receptor (AR) signaling is involved primarily in the development of male-specific phenotypes during embryogenesis, spermatogenesis, sexual behavior, and fertility during adult life. However, this signaling has also been shown to play an important role in development of female reproductive organs and their functions, such as ovarian folliculogenesis, embryonic implantation, and uterine and breast development. The establishment of the testicular feminization (Tfm) mouse model exploiting the X-linked Tfm mutation in mice has been a good in vivo tool for studying the human complete androgen insensitivity syndrome, but this mouse may not be the perfect in vivo model. Mouse models with various cell-specific AR knockout (ARKO) might allow us to study AR roles in individual types of cells in these male and female reproductive systems, although discrepancies are found in results between labs, probably due to using various Cre mice and/or knocking out AR in different AR domains. Nevertheless, no doubt exists that the continuous development of these ARKO mouse models and careful studies will provide information useful for understanding AR roles in reproductive systems of humans and may help us to develop more effective and more specific therapeutic approaches for reproductive system-related diseases. PMID:23782840
Acoustic Performance of a Real-Time Three-Dimensional Sound-Reproduction System
NASA Technical Reports Server (NTRS)
Faller, Kenneth J., II; Rizzi, Stephen A.; Aumann, Aric R.
2013-01-01
The Exterior Effects Room (EER) is a 39-seat auditorium at the NASA Langley Research Center and was built to support psychoacoustic studies of aircraft community noise. The EER has a real-time simulation environment which includes a three-dimensional sound-reproduction system. This system requires real-time application of equalization filters to compensate for spectral coloration of the sound reproduction due to installation and room effects. This paper describes the efforts taken to develop the equalization filters for use in the real-time sound-reproduction system and the subsequent analysis of the system s acoustic performance. The acoustic performance of the compensated and uncompensated sound-reproduction system is assessed for its crossover performance, its performance under stationary and dynamic conditions, the maximum spatialized sound pressure level it can produce from a single virtual source, and for the spatial uniformity of a generated sound field. Additionally, application examples are given to illustrate the compensated sound-reproduction system performance using recorded aircraft flyovers
USDA-ARS?s Scientific Manuscript database
The morphology of female Cyrtobagous salviniae Calder and Sands reproductive system is similar to other weevil species being meroistic and telotrophic and composed of two ovaries each with two tube-like ovarioles where the follicles develop and mature. A physiological age-grading system was develop...
Shimizu, Takashi; Hoshino, Yumi; Miyazaki, Hitoshi; Sato, Eimei
2012-01-01
The female reproductive organs such as ovary, uterus, and placenta are some of the few adult tissues that exhibit regular intervals of rapid growth, and are highly vascularized and have high rates of blood flow. Angiogenesis is a process of vascular growth that is mainly limited to the reproductive system in healthy adult animals. The development of new blood vessels in the ovary and uterus is essential to guarantee the necessary supply of nutrients and hormones. The genetic and molecular mechanisms that control the development of capillary blood vessels in the reproductive organs are beginning to be elucidated. Reproductive organs contain and produce angiogenic factors which may act alone or in concert to regulate the process of vasculature. Vascular endothelial growth factors (VEGFs) and fibroblast growth factor (FGFs) are key factors for vascular system in the reproductive organs. Recent numerous studies reported several roles of VEGFs and FGFs on ovarian and uterine functions. In this review, we focus on the involvement of VEGFs and FGFs as angiogenic factors on reproductive organs and vascular therapy for diseases of reproductive organs using anti-angiogenic agents.
Avanesian, Agnesa; Semnani, Sahar; Jafari, Mahtab
2009-08-01
Once a molecule is identified as a potential drug, the detection of adverse drug reactions is one of the key components of its development and the FDA approval process. We propose using Drosophila melanogaster to screen for reproductive adverse drug reactions in the early stages of drug development. Compared with other non-mammalian models, D. melanogaster has many similarities to the mammalian reproductive system, including putative sex hormones and conserved proteins involved in genitourinary development. Furthermore, the D. melanogaster model would present significant advantages in time efficiency and cost-effectiveness compared with mammalian models. We present data on methotrexate (MTX) reproductive adverse events in multiple animal models, including fruit flies, as proof-of-concept for the use of the D. melanogaster model.
Scsukova, Sona; Rollerova, Eva; Bujnakova Mlynarcikova, Alzbeta
2016-12-01
A growing body of evidence suggests that exposure to chemical substances designated as endocrine disrupting chemicals (EDCs) due to their ability to disturb endocrine (hormonal) activity in humans and animals, may contribute to problems with fertility, pregnancy, and other aspects of reproduction. The presence of EDCs has already been associated with reproductive malfunction in wildlife species, but it remains difficult to prove causal relationships between the presence of EDCs and specific reproductive problems in vivo, especially in females. On the other hand, the increasing number of experiments with laboratory animals and in vitro research indicate the ability of different EDCs to influence the normal function of female reproductive system, and even their association with cancer development or progression. Research shows that EDCs may pose the greatest risk during prenatal and early postnatal development when organ and neural systems are forming. In this review article, we aim to point out a possible contribution of EDCs to the onset and development of female reproductive disorders and endocrine-related cancers with regard to the period of exposure to EDCs and affected endpoints (organs or processes). Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.
Fern Gametophytes in Culture--A Simple System for Studying Plant Development and Reproduction.
ERIC Educational Resources Information Center
Dyer, A. F.
1983-01-01
Discusses fern life cycle and basic techniques for culturing fern gametophytes in the classroom. Also discusses investigations into the reproductive biology of ferns and into the early development of gametophytes. (JN)
Portik, Daniel M.; Blackburn, David C.
2016-01-01
The reproductive modes of anurans (frogs and toads) are the most diverse of terrestrial vertebrates, and a major challenge is identifying selective factors that promote the evolution or retention of reproductive modes across clades. Terrestrialized anuran breeding strategies have evolved repeatedly from the plesiomorphic fully aquatic reproductive mode, a process thought to occur through intermediate reproductive stages. Several selective forces have been proposed for the evolution of terrestrialized reproductive traits, but factors such as water systems and co‐evolution with ecomorphologies have not been investigated. We examined these topics in a comparative phylogenetic framework using Afrobatrachian frogs, an ecologically and reproductively diverse clade representing more than half of the total frog diversity found in Africa (∼400 species). We infer direct development has evolved twice independently from terrestrialized reproductive modes involving subterranean or terrestrial oviposition, supporting evolution through intermediate stages. We also detect associations between specific ecomorphologies and oviposition sites, and demonstrate arboreal species exhibit an overall shift toward using lentic water systems for breeding. These results indicate that changes in microhabitat use associated with ecomorphology, which allow access to novel sites for reproductive behavior, oviposition, or larval development, may also promote reproductive mode diversity in anurans. PMID:27402182
Regulation and roles of the hyaluronan system in mammalian reproduction.
Fouladi-Nashta, Ali A; Raheem, Kabir A; Marei, Waleed F; Ghafari, Fataneh; Hartshorne, Geraldine M
2017-02-01
Hyaluronan (HA) is a non-sulphated glycosaminoglycan polymer naturally occurring in many tissues and fluids of mammals, including the reproductive system. Its biosynthesis by HA synthase (HAS1-3) and catabolism by hyaluronidases (HYALs) are affected by ovarian steroid hormones. Depending upon its molecular size, HA functions both as a structural component of tissues in the form of high-molecular-weight HA or as a signalling molecule in the form of small HA molecules or HA fragments with effects mediated through interaction with its specific cell-membrane receptors. HA is produced by oocytes and embryos and in various segments of the reproductive system. This review provides information about the expression and function of members of the HA system, including HAS, HYALs and HA receptors. We examine their role in various processes from folliculogenesis through oocyte maturation, fertilisation and early embryo development, to pregnancy and cervical dilation, as well as its application in assisted reproduction technologies. Particular emphasis has been placed upon the role of the HA system in pre-implantation embryo development and embryo implantation, for which we propose a hypothetical sequential model. © 2017 Society for Reproduction and Fertility.
Microphysiological modeling of the reproductive tract: a fertile endeavor.
Eddie, Sharon L; Kim, J Julie; Woodruff, Teresa K; Burdette, Joanna E
2014-09-01
Preclinical toxicity testing in animal models is a cornerstone of the drug development process, yet it is often unable to predict adverse effects and tolerability issues in human subjects. Species-specific responses to investigational drugs have led researchers to utilize human tissues and cells to better estimate human toxicity. Unfortunately, human cell-derived models are imperfect because toxicity is assessed in isolation, removed from the normal physiologic microenvironment. Microphysiological modeling often referred to as 'organ-on-a-chip' or 'human-on-a-chip' places human tissue into a microfluidic system that mimics the complexity of human in vivo physiology, thereby allowing for toxicity testing on several cell types, tissues, and organs within a more biologically relevant environment. Here we describe important concepts when developing a repro-on-a-chip model. The development of female and male reproductive microfluidic systems is critical to sex-based in vitro toxicity and drug testing. This review addresses the biological and physiological aspects of the male and female reproductive systems in vivo and what should be considered when designing a microphysiological human-on-a-chip model. Additionally, interactions between the reproductive tract and other systems are explored, focusing on the impact of factors and hormones produced by the reproductive tract and disease pathophysiology. © 2014 by the Society for Experimental Biology and Medicine.
Cotton, Leanne M.; O’Bryan, Moira K.; Hinton, Barry T.
2008-01-01
The major function of the reproductive system is to ensure the survival of the species by passing on hereditary traits from one generation to the next. This is accomplished through the production of gametes and the generation of hormones that function in the maturation and regulation of the reproductive system. It is well established that normal development and function of the male reproductive system is mediated by endocrine and paracrine signaling pathways. Fibroblast growth factors (FGFs), their receptors (FGFRs), and signaling cascades have been implicated in a diverse range of cellular processes including: proliferation, apoptosis, cell survival, chemotaxis, cell adhesion, motility, and differentiation. The maintenance and regulation of correct FGF signaling is evident from human and mouse genetic studies which demonstrate that mutations leading to disruption of FGF signaling cause a variety of developmental disorders including dominant skeletal diseases, infertility, and cancer. Over the course of this review, we will provide evidence for differential expression of FGFs/FGFRs in the testis, male germ cells, the epididymis, the seminal vesicle, and the prostate. We will show that this signaling cascade has an important role in sperm development and maturation. Furthermore, we will demonstrate that FGF/FGFR signaling is essential for normal epididymal function and prostate development. To this end, we will provide evidence for the involvement of the FGF signaling system in the regulation and maintenance of the male reproductive system. PMID:18216218
Cotton, Leanne M; O'Bryan, Moira K; Hinton, Barry T
2008-04-01
The major function of the reproductive system is to ensure the survival of the species by passing on hereditary traits from one generation to the next. This is accomplished through the production of gametes and the generation of hormones that function in the maturation and regulation of the reproductive system. It is well established that normal development and function of the male reproductive system is mediated by endocrine and paracrine signaling pathways. Fibroblast growth factors (FGFs), their receptors (FGFRs), and signaling cascades have been implicated in a diverse range of cellular processes including: proliferation, apoptosis, cell survival, chemotaxis, cell adhesion, motility, and differentiation. The maintenance and regulation of correct FGF signaling is evident from human and mouse genetic studies which demonstrate that mutations leading to disruption of FGF signaling cause a variety of developmental disorders including dominant skeletal diseases, infertility, and cancer. Over the course of this review, we will provide evidence for differential expression of FGFs/FGFRs in the testis, male germ cells, the epididymis, the seminal vesicle, and the prostate. We will show that this signaling cascade has an important role in sperm development and maturation. Furthermore, we will demonstrate that FGF/FGFR signaling is essential for normal epididymal function and prostate development. To this end, we will provide evidence for the involvement of the FGF signaling system in the regulation and maintenance of the male reproductive system.
Portik, Daniel M; Blackburn, David C
2016-09-01
The reproductive modes of anurans (frogs and toads) are the most diverse of terrestrial vertebrates, and a major challenge is identifying selective factors that promote the evolution or retention of reproductive modes across clades. Terrestrialized anuran breeding strategies have evolved repeatedly from the plesiomorphic fully aquatic reproductive mode, a process thought to occur through intermediate reproductive stages. Several selective forces have been proposed for the evolution of terrestrialized reproductive traits, but factors such as water systems and co-evolution with ecomorphologies have not been investigated. We examined these topics in a comparative phylogenetic framework using Afrobatrachian frogs, an ecologically and reproductively diverse clade representing more than half of the total frog diversity found in Africa (∼400 species). We infer direct development has evolved twice independently from terrestrialized reproductive modes involving subterranean or terrestrial oviposition, supporting evolution through intermediate stages. We also detect associations between specific ecomorphologies and oviposition sites, and demonstrate arboreal species exhibit an overall shift toward using lentic water systems for breeding. These results indicate that changes in microhabitat use associated with ecomorphology, which allow access to novel sites for reproductive behavior, oviposition, or larval development, may also promote reproductive mode diversity in anurans. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
Marshall, Eleanor; Costa, Liliana M; Gutierrez-Marcos, Jose
2011-03-01
Cell-cell communication in plants is essential for the correct co-ordination of reproduction, growth, and development. Studies to dissect this mode of communication have previously focussed primarily on the action of plant hormones as mediators of intercellular signalling. In animals, peptide signalling is a well-documented intercellular communication system, however, relatively little is known about this system in plants. In recent years, numerous reports have emerged about small, secreted peptides controlling different aspects of plant reproduction. Interestingly, most of these peptides are cysteine-rich, and there is convincing evidence suggesting multiple roles for related cysteine-rich peptides (CRPs) as signalling factors in developmental patterning as well as during plant pathogen responses and symbiosis. In this review, we discuss how CRPs are emerging as key signalling factors in regulating multiple aspects of vegetative growth and reproductive development in plants.
Evolution: sociality as a driver of unorthodox reproduction.
Schwander, Tanja; Keller, Laurent
2012-07-10
An unusual reproductive system was discovered in desert ants, in which daughter queens are produced asexually via parthenogenesis, whereas workers develop from hybrid crosses between genetically divergent lineages. The system appears to be doomed to extinction. Copyright © 2012 Elsevier Ltd. All rights reserved.
HIGH-THROUGHPUT CELLULAR ASSAYS FOR MODELING TOXICITY IN THE FISH REPRODUCTIVE SYSTEM
The most important benefit of this project is the experimental evaluation of all essential steps in the development and testing of adverse outcome pathways (AOP) for a diverse set of reproductive and non-reproductive toxicants. In contrast to human testing and the toxicity pat...
Eisenberg, Lee; Johnson, Seth; Grodowitz, Michael J
2018-01-01
The morphology of the female Cyrtobagous salviniae Calder and Sands reproductive system is similar to other weevil species being meroistic and telotrophic. The reproductive system is composed of 2 ovaries each containing 2 ovarioles where the follicles mature. A physiological age grading system was developed where the continuum of ovarium development was divided into 2 nulliparous and 3 parous classes. This was based on the differentiation of the ovarioles, presence, and appearance of follicular relics, cuticle hardness/coloration, and fat body quantity/appearance. High correlation occurred between the parous classes and number of eggs produced where the P3 class had over 9-fold higher number of eggs in comparison with the P1 class. Mean number of eggs produced for each parous class was significantly different, however, overlap occurred. Such a system enables a determination of the past, present, and future reproductive status of field populations and mass-rearing colonies. PMID:29371784
The SLIT/ROBO pathway: a regulator of cell function with implications for the reproductive system
Dickinson, Rachel E; Duncan, W Colin
2010-01-01
The secreted SLIT glycoproteins and their Roundabout (ROBO) receptors were originally identified as important axon guidance molecules. They function as a repulsive cue with an evolutionarily conserved role in preventing axons from migrating to inappropriate locations during the assembly of the nervous system. In addition the SLIT-ROBO interaction is involved in the regulation of cell migration, cell death and angiogenesis and, as such, has a pivotal role during the development of other tissues such as the lung, kidney, liver and breast. The cellular functions that the SLIT/ROBO pathway controls during tissue morphogenesis are processes that are dysregulated during cancer development. Therefore inactivation of certain SLITs and ROBOs is associated with advanced tumour formation and progression in disparate tissues. Recent research has indicated that the SLIT/ROBO pathway could also have important functions in the reproductive system. The fetal ovary expresses most members of the SLIT and ROBO families. The SLITs and ROBOs also appear to be regulated by steroid hormones and regulate physiological cell functions in adult reproductive tissues such as the ovary and endometrium. Furthermore several SLITs and ROBOs are aberrantly expressed during the development of ovarian, endometrial, cervical and prostate cancer. This review will examine the roles this pathway could have in the development, physiology and pathology of the reproductive system and highlight areas for future research that could further dissect the influence of the SLIT/ROBO pathway in reproduction. PMID:20100881
The SLIT-ROBO pathway: a regulator of cell function with implications for the reproductive system.
Dickinson, Rachel E; Duncan, W Colin
2010-04-01
The secreted SLIT glycoproteins and their Roundabout (ROBO) receptors were originally identified as important axon guidance molecules. They function as a repulsive cue with an evolutionarily conserved role in preventing axons from migrating to inappropriate locations during the assembly of the nervous system. In addition the SLIT-ROBO interaction is involved in the regulation of cell migration, cell death and angiogenesis and, as such, has a pivotal role during the development of other tissues such as the lung, kidney, liver and breast. The cellular functions that the SLIT/ROBO pathway controls during tissue morphogenesis are processes that are dysregulated during cancer development. Therefore inactivation of certain SLITs and ROBOs is associated with advanced tumour formation and progression in disparate tissues. Recent research has indicated that the SLIT/ROBO pathway could also have important functions in the reproductive system. The fetal ovary expresses most members of the SLIT and ROBO families. The SLITs and ROBOs also appear to be regulated by steroid hormones and regulate physiological cell functions in adult reproductive tissues such as the ovary and endometrium. Furthermore several SLITs and ROBOs are aberrantly expressed during the development of ovarian, endometrial, cervical and prostate cancer. This review will examine the roles this pathway could have in the development, physiology and pathology of the reproductive system and highlight areas for future research that could further dissect the influence of the SLIT/ROBO pathway in reproduction.
Sex-specific inhibition and stimulation of worker-reproductive transition in a termite.
Sun, Qian; Haynes, Kenneth F; Hampton, Jordan D; Zhou, Xuguo
2017-09-06
In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.
Sex-specific inhibition and stimulation of worker-reproductive transition in a termite
NASA Astrophysics Data System (ADS)
Sun, Qian; Haynes, Kenneth F.; Hampton, Jordan D.; Zhou, Xuguo
2017-10-01
In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.
Tribbles role in reproduction.
Basatvat, Shaghayegh; Carter, Deborah Angela Louise; Kiss-Toth, Endre; Fazeli, Alireza
2015-10-01
Tribbles (TRIB) proteins, a family of evolutionary conserved psuedokinase proteins, modulate various signalling pathways within the cell. The regulatory roles of TRIB make them an important part of a number of biological processes ranging from cell proliferation to metabolism, immunity, inflammation and carcinogenesis. Innate immune system plays a pivotal role during the regulation of reproductive processes that allows successful creation of an offspring. Its involvement initiates from fertilization of the oocyte by spermatozoon and lasts throughout early embryonic development, pregnancy and labour. Therefore, there is a close cooperation between the reproductive system and the innate immune system. Evidence from our lab has demonstrated that improper activation of the innate immune system can reduce embryo implantation, thus leading to infertility. Therefore, control mechanisms regulating the innate immune system function can be critical for successful reproductive events. © 2015 Authors; published by Portland Press Limited.
Functional significance of GnRH and kisspeptin, and their cognate receptors in teleost reproduction.
Gopurappilly, Renjitha; Ogawa, Satoshi; Parhar, Ishwar S
2013-01-01
Guanine nucleotide binding protein (G-protein)-coupled receptors (GPCRs) are eukaryotic transmembrane proteins found in all living organisms. Their versatility and roles in several physiological processes make them the single largest family of drug targets. Comparative genomic studies using various model organisms have provided useful information about target receptors. The similarity of the genetic makeup of teleosts to that of humans and other vertebrates aligns with the study of GPCRs. Gonadotropin-releasing hormone (GnRH) represents a critical step in the reproductive process through its cognate GnRH receptors (GnRHRs). Kisspeptin (Kiss1) and its cognate GPCR, GPR54 (=kisspeptin receptor, Kiss-R), have recently been identified as a critical signaling system in the control of reproduction. The Kiss1/Kiss-R system regulates GnRH release, which is vital to pubertal development and vertebrate reproduction. This review highlights the physiological role of kisspeptin-Kiss-R signaling in the reproductive neuroendocrine axis in teleosts through the modulation of GnRH release. Moreover, we also review the recent developments in GnRHR and Kiss-R with respect to their structural variants, signaling mechanisms, ligand interactions, and functional significance. Finally, we discuss the recent progress in identifying many teleost GnRH-GnRHR and kisspeptin-Kiss-R systems and consider their physiological significance in the control of reproduction.
Development of a directivity controlled piezoelectric transducer for sound reproduction
NASA Astrophysics Data System (ADS)
Bédard, Magella; Berry, Alain
2005-04-01
One of the inherent limitations of loudspeaker systems in audio reproduction is their inability to reproduce the possibly complex acoustic directivity patterns of real sound sources. For music reproduction for example, it may be desirable to separate diffuse field and direct sound components and project them with different directivity patterns. Because of their properties, poly (vinylidene fluoride) (PVDF) films offer lot of advantages for the development of electroacoustic transducers. A system of piezoelectric transducers made with PVDF that show a controllable directivity was developed. A cylindrical omnidirectional piezoelectric transducer is used to produce an ambient field, and a piezoelectric transducers system, consisting of a series of curved sources placed around a cylinder frame, is used to produce a sound field with a given directivity. To develop the system, a numerical model was generated with ANSYS Multiphysics TM8.1 and used to calculate the mechanical response of the piezoelectric transducer. The acoustic radiation of the driver was then computed using the Kirchoff-Helmoltz theorem. Numerical and experimental results of the mechanical and acoustical response of the system will be shown.
Reproductive immunology: current status and future directions (part I).
Peeva, Elena
2010-12-01
Extensive research work over the past couple of decades has indicated a series of intricate relations between immune and reproductive systems. A range of reproductive immunology topics including the roles of adoptive and innate immunity in infertility and pregnancy, the immune system's role in induction of labor and preterm delivery, and immuno-modulatory effects of the female sex hormones will be discussed in this and the next issue of the Journal. The implications of this research on the development of novel therapeutic approaches are also addressed.
GnRH and GnRH receptors in the pathophysiology of the human female reproductive system.
Maggi, Roberto; Cariboni, Anna Maria; Marelli, Marina Montagnani; Moretti, Roberta Manuela; Andrè, Valentina; Marzagalli, Monica; Limonta, Patrizia
2016-04-01
Human reproduction depends on an intact hypothalamic-pituitary-gonadal (HPG) axis. Hypothalamic gonadotrophin-releasing hormone (GnRH) has been recognized, since its identification in 1971, as the central regulator of the production and release of the pituitary gonadotrophins that, in turn, regulate the gonadal functions and the production of sex steroids. The characteristic peculiar development, distribution and episodic activity of GnRH-producing neurons have solicited an interdisciplinary interest on the etiopathogenesis of several reproductive diseases. The more recent identification of a GnRH/GnRH receptor (GnRHR) system in both the human endometrium and ovary has widened the spectrum of action of the peptide and of its analogues beyond its hypothalamic function. An analysis of research and review articles published in international journals until June 2015 has been carried out to comprehensively summarize both the well established and the most recent knowledge on the physiopathology of the GnRH system in the central and peripheral control of female reproductive functions and diseases. This review focuses on the role of GnRH neurons in the control of the reproductive axis. New knowledge is accumulating on the genetic programme that drives GnRH neuron development to ameliorate the diagnosis and treatment of GnRH deficiency and consequent delayed or absent puberty. Moreover, a better understanding of the mechanisms controlling the episodic release of GnRH during the onset of puberty and the ovulatory cycle has enabled the pharmacological use of GnRH itself or its synthetic analogues (agonists and antagonists) to either stimulate or to block the gonadotrophin secretion and modulate the functions of the reproductive axis in several reproductive diseases and in assisted reproduction technology. Several inputs from other neuronal populations, as well as metabolic, somatic and age-related signals, may greatly affect the functions of the GnRH pulse generator during the female lifespan; their modulation may offer new possible strategies for diagnostic and therapeutic interventions. A GnRH/GnRHR system is also expressed in female reproductive tissues (e.g. endometrium and ovary), both in normal and pathological conditions. The expression of this system in the human endometrium and ovary supports its physiological regulatory role in the processes of trophoblast invasion of the maternal endometrium and embryo implantation as well as of follicular development and corpus luteum functions. The GnRH/GnRHR system that is expressed in diseased tissues of the female reproductive tract (both benign and malignant) is at present considered an effective molecular target for the development of novel therapeutic approaches for these pathologies. GnRH agonists are also considered as a promising therapeutic approach to counteract ovarian failure in young female patients undergoing chemotherapy. Increasing knowledge about the regulation of GnRH pulsatile release, as well as the therapeutic use of its analogues, offers interesting new perspectives in the diagnosis, treatment and outcome of female reproductive disorders, including tumoral and iatrogenic diseases. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Reproductive toxicity of carbon nanomaterials: a review
NASA Astrophysics Data System (ADS)
Vasyukova, I.; Gusev, A.; Tkachev, A.
2015-11-01
In the current review, we assembled the experimental evidences of an association between carbon nanomaterials including carbon black, graphite nanoplatelets, graphene, single- and multi-walled carbon nanotubes, and fullerene exposure and adverse reproductive and developmental effects, in vitro and in vivo studies. It is shown that carbon nanomaterials reveal toxic effect on reproductive system and offspring development of the animals of various system groups to a certain degree depending on carbon crystal structure. Although this paper provides initial information about the potential male and female reproductive toxicity of carbon nanomaterials, further studies, using characterized nanoparticles, relevant routes of administration, and doses closely reflecting all the expected levels of exposure are needed.
Shen, W; Chen, J; Yin, J; Wang, S-L
2016-01-01
Lead is a common environmental contaminant. Lead accumulation in the body is especially dangerous for pregnant women and newborns. Selenium is a trace element which may rectify the damaging effects of lead. Here we tested potential protective effects of selenium against gestational lead exposure. Pregnant SD rats were exposed to 200 mg/L of lead acetate (given with water), with or without sodium selenite supplementation (2-8 mg/kg/day via intragastric administration). Pregnant rats not exposed to lead or selenium served as control animals. The outcomes in pregnant rats were serum lead and selenium levels, reproductive hormone (follicle-stimulating hormone, luteinizing hormone, prolactin, oestradiol, progesterone) levels, and uterine and ovarian morphological changes. The outcomes in the offspring were sex differentiation, survival rates (day 21 after birth), weight (days 0-35 after birth), weight of reproductive organs, and puberty onset (foreskin separation or vaginal opening). Selenium supplementation dose-dependently decreased serum lead levels, rectified reproductive hormone levels, and attenuated reproductive morphological changes caused by lead exposure. Lead exposure did not affect sex differentiation, but significantly (p < 0.05 vs. control animals) decreased the offspring weight on days 0-28 and the weight of their reproductive organs. Furthermore, lead exposure delayed the onset of puberty. These pathological changes were dose-dependently rectified or attenuated by selenium supplementation. Gestational lead exposure causes damages to the reproductive system of pregnant rats, and negatively modulates growth and reproductive system development of the offspring. These adverse effects are rectified or attenuated by selenium supplementation.
Shemesh, Netta; Shai, Nadav; Meshnik, Lana; Katalan, Rotem; Ben-Zvi, Anat
2017-01-01
Caenorhabditis elegans somatic protein homeostasis (proteostasis) is actively remodeled at the onset of reproduction. This proteostatic collapse is regulated cell-nonautonomously by signals from the reproductive system that transmit the commitment to reproduction to somatic cells. Here, we asked whether the link between the reproductive system and somatic proteostasis could be uncoupled by activating downstream effectors in the gonadal longevity cascade. Specifically, we examined whether over-expression of lipl-4 (lipl-4(oe)), a target gene of the gonadal longevity pathway, or increase in arachidonic acid (AA) levels, associated with lipl-4(oe), modulated proteostasis and reproduction. We found that lipl-4(oe) rescued somatic proteostasis and postponed the onset of aggregation and toxicity in C. elegans models of polyglutamine (polyQ) diseases. However, lipl-4(oe) also disrupted fatty acid transport into developing oocytes and reduced reproductive success. In contrast, diet supplementation of AA recapitulated lipl-4(oe)-mediated proteostasis enhancement in wild type animals but did not affect the reproductive system. Thus, the gonadal longevity pathway mediates a trade-off between somatic maintenance and reproduction, in part by regulating the expression of genes, such as lipl-4, with inverse effects on somatic maintenance and reproduction. We propose that AA could uncouple such germline to soma crosstalk, with beneficial implications protein misfolding diseases. PMID:28503130
Salinas-Gamboa, Rigel; Johnson, Susan D; Sánchez-León, Nidia; Koltunow, Anna M G; Vielle-Calzada, Jean-Philippe
2016-06-01
Cowpea reproductive tools. Vigna unguiculata L. Walp. (cowpea) is recognized as a major legume food crop in Africa, but seed yields remain low in most varieties adapted to local conditions. The development of hybrid cowpea seed that could be saved after each generation, enabling significant yield increases, will require manipulation of reproductive development from a sexual to an asexual mode. To develop new technologies that could support the biotechnological manipulation of reproductive development in cowpea, we examined gametogenesis and seed formation in two transformable, African-adapted, day-length-insensitive varieties. Here, we show that these two varieties exhibit distinct morphological and phenological traits but share a common developmental sequence in terms of ovule formation and gametogenesis. We present a reproductive calendar that allows prediction of male and female gametogenesis on the basis of sporophytic parameters related to floral bud size and reproductive organ development, determining that gametogenesis occurs more rapidly in the anther than in the ovule. We also show that the mode of megagametogenesis is of the Polygonum-type and not Oenothera-type, as previously reported. Finally, we developed a whole-mount immunolocalization protocol and applied it to detect meiotic proteins in the cowpea megaspore mother cell, opening opportunities for comparing the dynamics of protein localization during male and female meiosis, as well as other reproductive events in this emerging legume model system.
Toxicity of Nanoparticles on the Reproductive System in Animal Models: A Review.
Brohi, Rahim Dad; Wang, Li; Talpur, Hira Sajjad; Wu, Di; Khan, Farhan Anwar; Bhattarai, Dinesh; Rehman, Zia-Ur; Farmanullah, F; Huo, Li-Jun
2017-01-01
In the last two decades, nanotechnologies demonstrated various applications in different fields, including detection, sensing, catalysis, electronics, and biomedical sciences. However, public concerns regarding the well-being of human may hinder the wide utilization of this promising innovation. Although, humans are exposed to airborne nanosized particles from an early age, exposure to such particles has risen dramatically within the last century due to anthropogenic sources of nanoparticles. The wide application of nanomaterials in industry, consumer products, and medicine has raised concerns regarding the potential toxicity of nanoparticles in humans. In this review, the effects of nanomaterials on the reproductive system in animal models are discussed. Females are particularly more vulnerable to nanoparticle toxicity, and toxicity in this population may affect reproductivity and fetal development. Moreover, various types of nanoparticles have negative impacts on male germ cells, fetal development, and the female reproductive system. These impacts are associated with nanoparticle modification, composition, concentration, route of administration, and the species of the animal. Therefore, understanding the impacts of nanoparticles on animal growth and reproduction is essential. Many studies have examined the effects of nanoparticles on primary and secondary target organs, with a concentration on the in vivo and in vitro effects of nanoparticles on the male and female reproductive systems at the clinical, cellular, and molecular levels. This review provides important information regarding organism safety and the potential hazards of nanoparticle use and supports the application of nanotechnologies by minimizing the adverse effects of nanoparticles in vulnerable populations.
Toxicity of Nanoparticles on the Reproductive System in Animal Models: A Review
Brohi, Rahim Dad; Wang, Li; Talpur, Hira Sajjad; Wu, Di; Khan, Farhan Anwar; Bhattarai, Dinesh; Rehman, Zia-Ur; Farmanullah, F.; Huo, Li-Jun
2017-01-01
In the last two decades, nanotechnologies demonstrated various applications in different fields, including detection, sensing, catalysis, electronics, and biomedical sciences. However, public concerns regarding the well-being of human may hinder the wide utilization of this promising innovation. Although, humans are exposed to airborne nanosized particles from an early age, exposure to such particles has risen dramatically within the last century due to anthropogenic sources of nanoparticles. The wide application of nanomaterials in industry, consumer products, and medicine has raised concerns regarding the potential toxicity of nanoparticles in humans. In this review, the effects of nanomaterials on the reproductive system in animal models are discussed. Females are particularly more vulnerable to nanoparticle toxicity, and toxicity in this population may affect reproductivity and fetal development. Moreover, various types of nanoparticles have negative impacts on male germ cells, fetal development, and the female reproductive system. These impacts are associated with nanoparticle modification, composition, concentration, route of administration, and the species of the animal. Therefore, understanding the impacts of nanoparticles on animal growth and reproduction is essential. Many studies have examined the effects of nanoparticles on primary and secondary target organs, with a concentration on the in vivo and in vitro effects of nanoparticles on the male and female reproductive systems at the clinical, cellular, and molecular levels. This review provides important information regarding organism safety and the potential hazards of nanoparticle use and supports the application of nanotechnologies by minimizing the adverse effects of nanoparticles in vulnerable populations. PMID:28928662
Heterochrony, cannibalism, and the evolution of viviparity in Salamandra salamandra.
Buckley, David; Alcobendas, Marina; García-París, Mario; Wake, Marvalee H
2007-01-01
The way in which novelties that lead to macroevolutionary events originate is a major question in evolutionary biology, and one that can be addressed using the fire salamander (Salamandra salamandra) as a model system. It is exceptional among amphibians in displaying intraspecific diversity of reproductive strategies. In S. salamandra, two distinct modes of reproduction co-occur: the common mode, ovoviviparity (females giving birth to many small larvae), and a phylogenetically derived reproductive strategy, viviparity (females producing only a few large, fully metamorphosed juveniles, which are nourished maternally). We examine the relationship between heterochronic modifications of the ontogeny and the evolution of the new reproductive mode in the fire salamander. The in vitro development of embryos of ovoviviparous and viviparous salamanders from fertilization to metamorphosis is compared, highlighting the key events that distinguish the two modes of reproduction. We identify the heterochronic events that, together with the intrauterine cannibalistic behavior, characterize the derived viviparous reproductive strategy. The ways in which evolutionary novelties can arise by modification of developmental programs can be studied in S. salamandra. Moreover, the variation in reproductive modes and the associated variation of sequences of development occur in neighboring, conspecific populations. Thus, S. salamandra is a unique biological system in which evolutionary developmental research questions can be addressed at the level of populations.
Colvin, Caroline Wingo; Abdullatif, Hussein
2013-01-01
Puberty is the period of biologic transition from childhood to adulthood. The changes that occur at this time are related to the increasing concentrations of sex steroid hormones. In females, most pubertal changes are caused by estrogen stimulation that results from the onset of central puberty. Significant development occurs in the organs of the female reproductive system and results in anatomic changes that characterize reproductive maturity. Adrenal and ovarian androgens also increase during puberty, affecting change that includes the promotion of certain secondary sex characteristics. The ability to recognize normal pubertal anatomy and distinguish between estrogen and androgen effects is important in the ability to diagnose and treat disorders of sex development, precocious puberty, pubertal delay, and menstrual irregularities in children and adolescents. An understanding of this developmental process can also help clinicians identify and treat reproductive pathology in adults and across all female life stages. Copyright © 2012 Wiley-Liss, Inc.
[Influencing factors for reproductive health of female workers in petrochemical industry].
Kou, Z X; Wang, S L; Chen, Z L; He, Y H; Yu, W L; Mei, L Y; Zhang, H D
2018-02-20
Objective: To investigate the reproductive health status of female workers in petrochemical industry, and to provide a reference for improving reproductive health status and developing preventive and control measures for female workers in petrochemical industry. Methods: A face-to-face questionnaire survey was performed from January to October, 2016. The Questionnaire on Women's Reproductive Health was used to investigate the reproductive health of female workers in petrochemical industry. The multivariate logistic regression model was used to identify the influencing factors for reproductive health of female workers in petrochemical industry. Results: Among the 7485 female workers, 1 268 (40.9%) had abnormal menstrual period, 1 437 (46.4%) had abnormal menstrual volume, 177 (28.5%) had hyperplasia of mammary glands, and 1 807 (24.6%) had gynecological inflammation. The reproductive system diseases in female workers in petrochemical industry were associated with the factors including age, marital status, education level, unhealthy living habits, abortion, overtime work, work shift, workload, video operation, occupational exposure, positive events, and negative events, and among these factors, negative events (odds ratio[ OR ]= 1.856) , unhealthy living habits ( OR =1.542) , and positive events ( OR =1.516) had greater impact on reproductive system diseases. Conclusion: Many chemical substances in the occupational environment of petrochemical industry can cause damage to the reproductive system, which not only affects the health of the female workers, but also poses potential threats to the health of their offspring. Occupational exposure, unhealthy living habits, overtime work, and work shift have great influence on reproductive system diseases in female workers.
Reproductive competence: a recurrent logic module in eukaryotic development
Noble, Luke M.; Andrianopoulos, Alex
2013-01-01
Developmental competence is the ability to differentiate in response to an appropriate stimulus, as first elaborated by Waddington in relation to organs and tissues. Competence thresholds operate at all levels of biological systems from the molecular (e.g. the cell cycle) to the ontological (e.g. metamorphosis and reproduction). Reproductive competence, an organismal process, is well studied in mammals (sexual maturity) and plants (vegetative phase change), though far less than later stages of terminal differentiation. The phenomenon has also been documented in multiple species of multicellular fungi, mostly in early, disparate literature, providing a clear example of physiological differentiation in the absence of morphological change. This review brings together data on reproductive competence in Ascomycete fungi, particularly the model filamentous fungus Aspergillus nidulans, contrasting mechanisms within Unikonts and plants. We posit reproductive competence is an elementary logic module necessary for coordinated development of multicellular organisms or functional units. This includes unitary multicellular life as well as colonial species both unicellular and multicellular (e.g. social insects such as ants). We discuss adaptive hypotheses for developmental and reproductive competence systems and suggest experimental work to address the evolutionary origins, generality and genetic basis of competence in the fungal kingdom. PMID:23864594
Functional Significance of GnRH and Kisspeptin, and Their Cognate Receptors in Teleost Reproduction
Gopurappilly, Renjitha; Ogawa, Satoshi; Parhar, Ishwar S.
2012-01-01
Guanine nucleotide binding protein (G-protein)-coupled receptors (GPCRs) are eukaryotic transmembrane proteins found in all living organisms. Their versatility and roles in several physiological processes make them the single largest family of drug targets. Comparative genomic studies using various model organisms have provided useful information about target receptors. The similarity of the genetic makeup of teleosts to that of humans and other vertebrates aligns with the study of GPCRs. Gonadotropin-releasing hormone (GnRH) represents a critical step in the reproductive process through its cognate GnRH receptors (GnRHRs). Kisspeptin (Kiss1) and its cognate GPCR, GPR54 (=kisspeptin receptor, Kiss-R), have recently been identified as a critical signaling system in the control of reproduction. The Kiss1/Kiss-R system regulates GnRH release, which is vital to pubertal development and vertebrate reproduction. This review highlights the physiological role of kisspeptin-Kiss-R signaling in the reproductive neuroendocrine axis in teleosts through the modulation of GnRH release. Moreover, we also review the recent developments in GnRHR and Kiss-R with respect to their structural variants, signaling mechanisms, ligand interactions, and functional significance. Finally, we discuss the recent progress in identifying many teleost GnRH-GnRHR and kisspeptin-Kiss-R systems and consider their physiological significance in the control of reproduction. PMID:23482509
Reproductive Steroid Regulation of Mood and Behavior.
Schiller, Crystal Edler; Johnson, Sarah L; Abate, Anna C; Schmidt, Peter J; Rubinow, David R
2016-06-13
In this article, we examine evidence supporting the role of reproductive steroids in the regulation of mood and behavior in women and the nature of that role. In the first half of the article, we review evidence for the following: (i) the reproductive system is designed to regulate behavior; (ii) from the subcellular to cellular to circuit to behavior, reproductive steroids are powerful neuroregulators; (iii) affective disorders are disorders of behavioral state; and (iv) reproductive steroids affect virtually every system implicated in the pathophysiology of depression. In the second half of the article, we discuss the diagnosis of the three reproductive endocrine-related mood disorders (premenstrual dysphoric disorder, postpartum depression, and perimenopausal depression) and present evidence supporting the relevance of reproductive steroids to these conditions. Existing evidence suggests that changes in reproductive steroid levels during specific reproductive states (i.e., the premenstrual phase of the menstrual cycle, pregnancy, parturition, and the menopause transition) trigger affective dysregulation in susceptible women, thus suggesting the etiopathogenic relevance of these hormonal changes in reproductive mood disorders. Understanding the source of individual susceptibility is critical to both preventing the onset of illness and developing novel, individualized treatments for reproductive-related affective dysregulation. © 2016 American Physiological Society. Compr Physiol 6:1135-1160, 2016e. Copyright © 2016 John Wiley & Sons, Inc.
Activins in reproductive biology and beyond.
Wijayarathna, R; de Kretser, D M
2016-04-01
Activins are members of the pleiotrophic family of the transforming growth factor-beta (TGF-β) superfamily of cytokines, initially isolated for their capacity to induce the release of FSH from pituitary extracts. Subsequent research has demonstrated that activins are involved in multiple biological functions including the control of inflammation, fibrosis, developmental biology and tumourigenesis. This review summarizes the current knowledge on the roles of activin in reproductive and developmental biology. It also discusses interesting advances in the field of modulating the bioactivity of activins as a therapeutic target, which would undoubtedly be beneficial for patients with reproductive pathology. A comprehensive literature search was carried out using PUBMED and Google Scholar databases to identify studies in the English language which have contributed to the advancement of the field of activin biology, since its initial isolation in 1987 until July 2015. 'Activin', 'testis', 'ovary', 'embryonic development' and 'therapeutic targets' were used as the keywords in combination with other search phrases relevant to the topic of activin biology. Activins, which are dimers of inhibin β subunits, act via a classical TGF-β signalling pathway. The bioactivity of activin is regulated by two endogenous inhibitors, inhibin and follistatin. Activin is a major regulator of testicular and ovarian development. In the ovary, activin A promotes oocyte maturation and regulates granulosa cell steroidogenesis. It is also essential in endometrial repair following menstruation, decidualization and maintaining pregnancy. Dysregulation of the activin-follistatin-inhibin system leads to disorders of female reproduction and pregnancy, including polycystic ovary syndrome, ectopic pregnancy, miscarriage, fetal growth restriction, gestational diabetes, pre-eclampsia and pre-term birth. Moreover, a rise in serum activin A, accompanied by elevated FSH, is characteristic of female reproductive aging. In the male, activin A is an autocrine and paracrine modulator of germ cell development and Sertoli cell proliferation. Disruption of normal activin signalling is characteristic of many tumours affecting reproductive organs, including endometrial carcinoma, cervical cancer, testicular and ovarian cancer as well as prostate cancer. While activin A and B aid the progression of many tumours of the reproductive organs, activin C acts as a tumour suppressor. Activins are important in embryonic induction, morphogenesis of branched glandular organs, development of limbs and nervous system, craniofacial and dental development and morphogenesis of the Wolffian duct. The field of activin biology has advanced considerably since its initial discovery as an FSH stimulating agent. Now, activin is well known as a growth factor and cytokine that regulates many aspects of reproductive biology, developmental biology and also inflammation and immunological mechanisms. Current research provides evidence for novel roles of activins in maintaining the structure and function of reproductive and other organ systems. The fact that activin A is elevated both locally as well as systemically in major disorders of the reproductive system makes it an important biomarker. Given the established role of activin A as a pro-inflammatory and pro-fibrotic agent, studies of its involvement in disorders of reproduction resulting from these processes should be examined. Follistatin, as a key regulator of the biological actions of activin, should be evaluated as a therapeutic agent in conditions where activin A overexpression is established as a contributing factor. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Reproductive health/family planning and the health of infants, girls and women.
Sadik, N
1997-01-01
The 1994 International Conference on Population and Development developed international consensus amongst health providers, policy makers, and group representing the whole of civil society regarding the concept of reproductive health and its definition. In line with this definition, reproductive health care is defined as the constellation of methods, techniques and services that contribute to reproductive health and well-being by preventing and solving reproductive health problems. Reproductive health care saves lives and prevents significant levels of morbidity through family planning programmes, antenatal, delivery and post-natal services, prevention and management programmes for reproductive tract infections (including sexually transmitted diseases and HIV/AIDS), prevention of abortion and management of its complications, cancers of the reproductive system, and harmful practices that impact on reproductive function. Reproductive health care needs are evident at all stages of the life cycle and account for a greater proportion of disability adjusted life years (DALYS) in girls and women than in boys and men. Reproductive health protects infant health by enabling birth spacing and birth limitation to be practiced through family planning. The prevention and early detection of reproductive tract infections, including sexually transmitted diseases and HIV, through the integration of preventive measures in family planning service delivery not only improves the quality of care provided but is also directly responsible for improvement in survival and health of infants. Addressing harmful practices such as son preference, sex selection, sexual violence and female genital mutilation complements the positive impact of planned and spaced children through family planning services on infant mortality and the reproductive health of young girls and women. They are also in addition to prenatal, delivery and postnatal services, positive determinants of low maternal mortality and morbidity and are integral to the promotion of reproductive health in women of child bearing age. Reproductive tract infections, including sexually transmitted diseases and HIV contribute to significant level of ill-health in women of reproductive age and continue to pose a threat through the menopause which in turn brings with it increasing risk of cancers of the reproductive system.
Thyroid hormones and female reproduction.
Silva, Juneo F; Ocarino, Natália M; Serakides, Rogéria
2018-05-14
Thyroid hormones are vital for the proper functioning of the female reproductive system, since they modulate the metabolism and development of ovarian, uterine and placental tissues. Therefore, hypo- and hyperthyroidism may result in subfertility or infertility in both women and animals. Other well-documented sequelae of maternal thyroid dysfunctions include menstrual/estral irregularity, anovulation, abortion, preterm delivery, preeclampsia, intrauterine growth restriction, postpartum thyroiditis, and mental retardation in children. Several studies have been carried out involving prospective and retrospective studies of women with thyroid dysfunction, as well as in vivo and in vitro assays of hypo- and hyperthyroidism using experimental animal models and/or ovarian, uterine and placental cell culture. These studies have sought to elucidate the mechanisms by which thyroid hormones influence reproduction to better understand the physiology of the reproductive system and to provide better therapeutic tools for reproductive dysfunctions that originate from thyroid dysfunctions. Therefore, this review aims to summarize and update the available information related to the role of thyroid hormones in the morphophysiology of the ovary, uterus and placenta in women and animals and the effects of hypo- and hyperthyroidism on the female reproductive system.
2014-01-01
Background The Sterile Insect Technique (SIT) is an accepted species-specific genetic control approach that acts as an insect birth control measure, which can be improved by biotechnological engineering to facilitate its use and widen its applicability. First transgenic insects carrying a single killing system have already been released in small scale trials. However, to evade resistance development to such transgenic approaches, completely independent ways of transgenic killing should be established and combined. Perspective Most established transgenic sexing and reproductive sterility systems are based on the binary tTA expression system that can be suppressed by adding tetracycline to the food. However, to create 'redundant killing' an additional independent conditional expression system is required. Here we present a perspective on the use of a second food-controllable binary expression system - the inducible Q system - that could be used in combination with site-specific recombinases to generate independent transgenic killing systems. We propose the combination of an already established transgenic embryonic sexing system to meet the SIT requirement of male-only releases based on the repressible tTA system together with a redundant male-specific reproductive sterility system, which is activated by Q-system controlled site-specific recombination and is based on a spermatogenesis-specifically expressed endonuclease acting on several species-specific target sites leading to chromosome shredding. Conclusion A combination of a completely independent transgenic sexing and a redundant reproductive male sterility system, which do not share any active components and mediate the induced lethality by completely independent processes, would meet the 'redundant killing' criteria for suppression of resistance development and could therefore be employed in large scale long-term suppression programs using biotechnologically enhanced SIT. PMID:25471733
Lectin-functionalized magnetic iron oxide nanoparticles for reproductive improvement
USDA-ARS?s Scientific Manuscript database
Background: Semen ejaculates contain heterogeneous sperm populations that can jeopardize male fertility. Recent development of nanotechnology in physiological systems may have applications in reproductive biology. Here, we used magnetic nanoparticles as a novel strategy for sperm purification to imp...
REPRODUCTIVE TOXICITY OF PHTHALATE ESTERS
Phthalate esters display several modes of toxicity in mammalian species. In the rat, in utero exposure at relatively low dosage levels disrupts development of the reproductive system of the male rat by altering fetal testis hormone production. This presentation is a review of t...
Development of an in vitro diaphragm motion reproduction system.
Liao, Ai-Ho; Chuang, Ho-Chiao; Shih, Ming-Chih; Hsu, Hsiao-Yu; Tien, Der-Chi; Kuo, Chia-Chun; Jeng, Shiu-Chen; Chiou, Jeng-Fong
2017-07-01
This study developed an in vitro diaphragm motion reproduction system (IVDMRS) based on noninvasive and real-time ultrasound imaging to track the internal displacement of the human diaphragm and diaphragm phantoms with a respiration simulation system (RSS). An ultrasound image tracking algorithm (UITA) was used to retrieve the displacement data of the tracking target and reproduce the diaphragm motion in real time using a red laser to irradiate the diaphragm phantom in vitro. This study also recorded the respiration patterns in 10 volunteers. Both simulated and the respiration patterns in 10 human volunteers signals were input to the RSS for conducting experiments involving the reproduction of diaphragm motion in vitro using the IVDMRS. The reproduction accuracy of the IVDMRS was calculated and analyzed. The results indicate that the respiration frequency substantially affects the correlation between ultrasound and kV images, as well as the reproduction accuracy of the IVDMRS due to the system delay time (0.35s) of ultrasound imaging and signal transmission. The utilization of a phase lead compensator (PLC) reduced the error caused by this delay, thereby improving the reproduction accuracy of the IVDMRS by 14.09-46.98%. Applying the IVDMRS in clinical treatments will allow medical staff to monitor the target displacements in real time by observing the movement of the laser beam. If the target displacement moves outside the planning target volume (PTV), the treatment can be immediately stopped to ensure that healthy tissues do not receive high doses of radiation. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Yu, Miao; Chen, Liangkai; Peng, Zhao; Nüssler, Andreas K; Wu, Qinghua; Liu, Liegang; Yang, Wei
2017-06-01
Deoxynivalenol (DON) is a toxic fungal secondary metabolite produced by molds of the Fusarium genus, and it is known to cause a spectrum of diseases both in humans and animals, such as emesis, diarrhea, anorexia, immunotoxicity, hematological disorders, impairment of maternal reproduction, and fetal development. The recently revealed teratogenic potential of DON has received much attention. In various animal models, it has been shown that DON led to skeletal deformities of the fetus. However, the underlying mechanisms are not yet fully understood, and toxicological data are also scarce. Several animal research studies highlight the potential link between morphological abnormalities and changes of autophagy in the reproductive system. Because autophagy is involved in fetal development, maintenance of placental function, and bone remodeling, this mechanism has become a high priority for future research. The general aim of the present review is to deliver a comprehensive overview of the current state of knowledge of DON-induced reproductive toxicity in different animal models and to provide some prospective ideas for further research. The focus of the current review is to summarize toxic and negative effects of DON exposure on the reproductive system and the potential underlying molecular mechanisms in various animal models. Copyright © 2017 Elsevier B.V. All rights reserved.
PE are a large family of compounds used in a wide array of consumer, industrial and medical products. Studies have shown that in utero treatment with PE such as diethyl hexyl phthalate (DEHP) during the critical period of fetal reproductive development produced male reproductive ...
Plant reproduction in spaceflight environments
NASA Technical Reports Server (NTRS)
Musgrave, M. E.; Kuang, A.; Porterfield, D. M.
1997-01-01
Because plant reproduction is a complex developmental process there are many possible sites of perturbation by the unusual environments of orbital spacecraft. Previous long-duration experiments on Soviet platforms shared features of slowed development through the vegetative stage of plant growth and aborted reproductive function. Our goal has been to understand how special features of the spaceflight environment impact physiological function and reproductive development. In a series of short-duration experiments in the Shuttle mid-deck we studied early reproductive development in Arabidopsis thaliana. Pollen and ovule development aborted at an early stage in the first experiment on STS-54 which utilized closed plant growth chambers. Post-flight analysis suggested that the plants may have been carbon dioxide limited. Subsequent experiments utilized carbon dioxide enrichment (on STS-51) and cabin air flow-through with an air exchange system (on STS-68). Both modifications allowed pollen and ovule development to occur normally on orbit, and full reproductive development up to the stage of an immature seed occurred on STS-68. However, analysis of plant roots from these experiments demonstrated a limitation in rootzone aeration in the spaceflight material that was not mitigated by these procedures. In the future, additional resources (crew time, upgraded flight hardware, and special platforms) will invite more elaborate, long-duration experimentation. On the ISS, a variable speed centrifuge and upgraded plant habitats will permit detailed experiments on the role of gravity in shaping the plant micro-environment, and what influence this plays during reproduction.
Novel Use of Ultrasound to Teach Reproductive System Physical Examination Skills and Pelvic Anatomy.
Parikh, Tejal; Czuzak, Maria; Bui, Naomi; Wildner, Corinna; Koch, Bryna; Leko, Elizabeth; Rappaport, William; Adhikari, Srikar; Gordon, Paul; Gura, Mike; Ellis, Susan
2018-03-01
To determine whether integration of ultrasound (US) into a reproductive system examination clinical skills lab can increase confidence in palpating key reproductive structures during testicular and bimanual pelvic examinations, reduce anxiety about conducting testicular and bimanual pelvic examinations, and improve performance on multiple-choice questions based on structure identification using US images. Second-year medical students enrolled in the Life Cycle preclinical course participated in this cross-sectional study. A single learning activity was developed to pair the teaching of the reproductive system physical examination with the use of US in the clinical skills lab. The evaluation of the teaching session consisted of a pre-post analysis of student self-reported knowledge, confidence, and anxiety. The response rate for the pre survey was 82% (n = 96), and the rate for the post survey was 79% (n = 93). Students' confidence in their ability to identify reproductive system structures on US images increased from pre to post survey. Their confidence in their ability to palpate the epididymis, uterus, and ovary during a physical examination improved, and their anxiety about conducting testicular and bimanual pelvic examinations decreased. Student satisfaction with the session was high. Students' performance on multiple-choice questions based on structure identification using US images was at 96% or higher. Our study findings support the integration of US into a reproductive system examination clinical skills lab. Medical students acquire competency and confidence in reproductive system physical examination skills with US integration. © 2017 by the American Institute of Ultrasound in Medicine.
Major advances associated with reproduction in dairy cattle.
Moore, K; Thatcher, W W
2006-04-01
The purpose of this overview is to review some of the major advances in reproductive technologies, and how they may be applied to meet the challenge of enhancing reproductive efficiency in the high-producing dairy cow of the 21st century. The current population of high-producing dairy cows is considered to be subfertile, as characterized by low pregnancy rates and high rates of embryonic mortality. Coordinated systems of reproductive management have been developed based upon a thorough understanding of the endocrine, cellular, and molecular factors controlling ovarian and uterine function. These systems will partially restore herd reproductive performance. Advances in other reproductive technologies offer possibilities for wider use of superior germplasm. Technologies such as sexed semen, cloning, transgenesis, and preimplantation genetic diagnosis offer the potential to enhance the influence of superior animals on production of food for human consumption. However, at this time, additional research is needed to counteract the higher rates of embryonic and fetal mortality associated with some of these technologies. Furthermore, use of genomics, proteomics, and bioinformatics in the study of reproduction will undoubtedly provide investigators with a greater understanding of the limitations to efficient reproductive processes in the subfertile lactating dairy cow.
Oviparous vertebrates generally occupy important niches in aquatic as well as terrestrial systems, and reproductive and developmental effects on these species can be of relatively great ecological significance. Because these organisms have critical windows of development, they ma...
Developmental and reproductive toxixology (DART) has routinely been a part of safety assessment. Attention is now focused on the effects of chemicals on the developing nervous and immune systems. This focus on developmental neurotoxicology (DNT) and developmental immunotoxicolo...
Viruses in the Mammalian Male Genital Tract and Their Effects on the Reproductive System
Dejucq, Nathalie; Jégou, Bernard
2001-01-01
This review describes the various viruses identified in the semen and reproductive tracts of mammals (including humans), their distribution in tissues and fluids, their possible cell targets, and the functional consequences of their infectivity on the reproductive and endocrine systems. The consequences of these viral infections on the reproductive tract and semen can be extremely serious in terms of organ integrity, development of pathological and cancerous processes, and transmission of diseases. Furthermore, of essential importance is the fact that viral infection of the testicular cells may result not only in changes in testicular function, a serious risk for the fertility and general health of the individual (such as a fall in testosteronemia leading to cachexia), but also in the possible transmission of virus-induced mutations to subsequent generations. In addition to providing an exhaustive account of the data available in these domains, this review focuses attention on the fact that the interface between endocrinology and virology has so far been poorly explored, particularly when major health, social and economical problems are posed. Our conclusions highlight the research strategies that need to be developed. Progress in all these domains is essential for the development of new treatment strategies to eradicate viruses and to correct the virus-induced dysfunction of the endocrine system. PMID:11381100
Gao, Ming-Qing; Zhang, Ruiqi; Yang, Yange; Luo, Yuru; Jiang, Ming; Zhang, Yingli; Zhang, Yong; Qing, Suzhu
2018-05-01
Bovine mastitis is an infectious disease of the mammary gland which has been generally treated by antibiotic delivery. While the increasing drug-resistant bacteria and the high consumption of the antibiotic had become a noticeable concern. In a previous study, a mammary special vector expressing human β-defensin 3 (hBD3) was transfected into bovine fetal fibroblasts to produce mastitis-resistant bovine. This investigation focused on potential unintended effects of transgenic milk containing hBD3 produced by these mastitis-resistant bovine on the reproductive system of C57BL/6J mice. Mice were fed with diets containing transgenic milk or conventional milk, nutritionally balanced to an AIN93G diet for 90 days, and non-milk diet was selected as the negative group. The reproductive system was given special attention including reproductive organ/body ratios, necropsy and histopathology, serum sex hormone, sperm parameters, estrus cycle and the expression level of some specific genes which could indicate the development and function of reproductive system. No diet-related significant differences were observed among three groups in this 90-day feeding study. The results indicated that hBD3 milk does not appear to exert any effect on the reproductive system in C57BL/6J rats compared with conventional milk or the control diet. Copyright © 2018 Elsevier Ltd. All rights reserved.
Davies, Scott; Behbahaninia, Hirbod; Giraudeau, Mathieu; Meddle, Simone L; Waites, Kyle; Deviche, Pierre
2015-12-01
Urban animals inhabit an environment considerably different than do their non-urban conspecifics, and to persist urban animals must adjust to these novel environments. The timing of seasonal reproductive development (i.e., growth of gonads and secondary sex organs) is a fundamental determinant of the breeding period and is frequently advanced in urban bird populations. However, the underlying mechanism(s) by which birds adjust the timing of reproductive development to urban areas remain(s) largely unknown. Here, we compared the timing of vernal reproductive development in free-ranging urban and non-urban male Abert's Towhees, Melozone aberti, in Phoenix, Arizona, USA, and tested the non-mutually exclusive hypotheses that earlier reproductive development is due to improved energetic status and/or earlier increase in endocrine activity of the reproductive system. We found that urban birds initiated testicular development earlier than non-urban birds, but this disparity was not associated with differences in body condition, fat stores, or innate immune performance. These results provide no support for the hypothesis that energetic constraints are responsible for delayed reproductive development of non-urban relative to urban male Abert's Towhees. Urban birds did, however, increase their plasma luteinizing hormone, but not plasma testosterone, earlier than non-urban birds. These findings suggest that adjustment to urban areas by Abert's Towhees involves increases in the endocrine activity of the anterior pituitary gland and/or hypothalamus earlier than non-urban towhees. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Ji, Ting; Xu, Jing-Jing; Mace, Ruth
2014-03-01
Here we argue that models developed to examine cooperation and conflict in communal breeders, using a "tug-of-war" model of reproductive skew generated by incomplete control, are an appropriate way to model human kinship systems. We apply such models to understand the patterns of effort put into competition between father and son and between brothers in conflict over family resources in a patrilineal kinship system. Co-resident kin do not necessarily emerge with equal shares of the cake in terms of reproductive output. The models show that, depending on the efficiency with which they can gain more control of the resource, on the marriage system, and on the relatedness of the partners in conflict, individuals can do better to help their relatives breed rather than fight each other for the resources needed to reproduce. The models show that when a son's father is still breeding with his mother, sons should not compete for any share of reproduction. However, under polygyny, increased effort is spent on father/son and brother/brother conflict. Fathers will win the majority of reproduction if dominant to sons (in contrast to the finding that daughters-in-law win in conflict over mothers-in-law in patrilocal kinship systems, which has been suggested as explaining the evolution of menopause). Hence who wins in the sharing of reproduction depends not just on which sex disperses but also on the relative competitive ability of all individuals to exploit family resources. Anthropologists have long argued that cultural norms can reduce conflict. These formal evolutionary models help us to quantify the effects of reproductive conflict in families, throwing light on the evolutionary basis not just of patterns of reproductive scheduling, but also human kinship and marriage systems.
The male reproductive system of Hippolyte inermis Leach 1815 (Decapoda, Caridea)
NASA Astrophysics Data System (ADS)
Cobos, Vanesa; Díaz, Vanessa; Raso, Jose Enrique García; Manjón-Cabeza, M. E.
2011-03-01
The present work completes a series of studies on the biology of the shrimp Hippolyte inermis Leach 1815, where we suggested the species to be gonochoristic. The morphology of the male reproductive system (testes, vasa deferentia, gonopores) and the different stages of male germ cell development are described for the first time in the genus Hippolyte, using TEM, SEM, and histological methods. All males from 1.70 to 3.42 mm in carapace length had active testes and well-developed vasa deferentia. No case of sex reversal could be found.
Endocrine control of epigenetic mechanisms in male reproduction.
Ankolkar, Mandar; Balasinor, N H
2016-01-01
Endocrine control of reproduction is very well known and has been echoed by many research groups. However, recent developments point to the ability of toxic endocrine disrupting chemicals (EDC) to alter epigenetic information of the gametes which gets transferred to the developing embryo and affects the immediate reproductive outcome or even persists transgenerationally. These epigenetic aberrations contribute to the ensuing pathophysiology of reproductive disorders. Investigations of the female in cases of poor reproductive outcome have been the main strategy towards diagnosis. However, despite the male partner contributing half of his genome to the progeny, thorough investigations in the male have been ignored. Environmental pollutants are all pervading and are encountered in our day-to-day life. Many of these pollutants have potential to disrupt the endocrine system. Here, we discuss how the male gametes (spermatozoa) are susceptible to a myriad of epigenetic insults inflicted by exposure to endocrine disruptors and how important is the contribution of the epigenetic marks of the spermatozoa in healthy reproduction. We advocate that sperm epigenetics should be considered as a significant contributor to reproductive health and should be researched further and be subsequently included in routine diagnostic workup in cases of poor reproductive outcome.
REPRODUCTIVE AND DEVELOPMENTAL TOXICITY ASSOCIATED WITH DISINFECTION BY-PRODUCTS OF DRINKING WATER
Over the past decade many toxicologic studies have addressed the potential for disinfection byproducts of drinking water to elicit alterations on the reproductive system and fetal development.
The types and designs of these studies vary considerably, but in general they can ...
Adverse trends in male reproductive health have been reported for increased rates of testicular germ cell tumor, low semen quality, cryptorchidism, and hypospadias. An association with prenatal environmental exposure has been inferred from human and animal studies underlying male...
Maffucci, Jacqueline A.; Gore, Andrea C.
2009-01-01
The hypothalamic-pituitary-gonadal (HPG) axis undergoes a number of changes throughout the reproductive life cycle that are responsible for the development, puberty, adulthood, and senescence of reproductive systems. This natural progression is dictated by the neural network controlling the hypothalamus including the cells that synthesize and release gonadotropin-releasing hormone (GnRH) and their regulatory neurotransmitters. Glutamate and GABA are the primary excitatory and inhibitory neurotransmitters in the central nervous system, and as such contribute a great deal to modulating this axis throughout the lifetime via their actions on receptors in the hypothalamus, both directly on GnRH neurons as well as indirectly though other hypothalamic neural networks. Interactions among GnRH neurons, glutamate, and GABA, including the regulation of GnRH gene and protein expression, hormone release, and modulation by estrogen, are critical to age-appropriate changes in reproductive function. Here, we present evidence for the modulation of GnRH neurosecretory cells by the balance of glutamate and GABA in the hypothalamus, and the functional consequences of these interactions on reproductive physiology across the life cycle. PMID:19349036
Studies of lead exposure on reproductive system: a review of work in China.
Xuezhi, J; Youxin, L; Yilan, W
1992-09-01
This paper, based on a review of a series studies conducted in China from 1978 through 1991, describes the possible links between low level lead exposure and the adverse effects on reproductive system. Effects on menstrual status and pregnancy outcome manifested mainly as higher prevalences of menstrual disturbance, spontaneous abortion and threatened abortion in exposed females. Transfer of lead via placenta and human milk was shown by higher lead levels in milk and blood of infant. Impairment of male reproductive function was observed as decreased volume of ejaculation, prolonged latency of semen melting, reduced total sperm count and alive spermatozoa, retarded sperm activity as well as lowered density of semen fluid in exposed male workers with Pb-B over 40 micrograms.dl-1. In addition, poorer performance of WISC-R test was revealed in children with Pb-B level over 30 micrograms.dl-1, and retarded physical development was observed in children with Pb-B over 20 micrograms.dl-1. Therefore, health surveillance including the assessment of adverse effects on reproductive system of both female and male lead exposed workers should not be ignored. Furthermore, safety exposure limit of work place, particularly for female workers of child-bearing age, should be developed.
Wang, Guo-yao; Ji, Yun-xin; Ding, Hui-qing; Gui, Zhong-bao; Liang, Xiao-ming; Fu, Jian-fei; Cheng, Yue
2015-12-01
To investigate how network education can improve college students' knowledge on sexual and reproductive health in Ningbo city. From December 2012 to June 2013, we conducted a questionnaire investigation among college students in Ningbo city about the effects of network education on their knowledge about sexual psychology, sexual physiology, sexual ethics, and reproductive health. A total of 7 362 college students accomplished the investigation, of whom 2 483 (42.1% males and 57.9% females) received network education, while the other 4 879 (24.1% males and 75.9% females) did not. Approximately 47.1% of the male and 28.0% of the female students acquired sexual and reproductive knowledge via network education. Reproductive health-related network education significantly enriched the students' knowledge about the reproductive system and sex, pubertal development, sexual physiology, conception and embryonic development, methods of contraception, sexual psychology, sexually transmitted diseases and their prevention, pregnancy care and eugenics, and environment- and occupation-related reproductive health (P < 0.01). It also remarkably improved their cognitive attitude towards reproductive health knowledge (P < 0.01). Those who received reproductive health-related network education showed a significantly higher rate of masturbation (P < 0.01) but markedly later time of the first masturbation (P < 0.01) than those who did not. Network education can enhance the effect of reproductive health education among college students and improve their sexual experience and health.
Cryptic postzygotic isolation in an eruptive species of bark beetle (Dendroctonus ponderosae)
Ryan R. Bracewell; Michael E. Pfrender; Karen E. Mock; Barbara J. Bentz
2011-01-01
Studies of postzygotic isolation often involve well-differentiated taxa that show a consistent level of incompatibility, thereby limiting our understanding of the initial stages and development of reproductive barriers. Dendroctonus ponderosae provides an informative system because recent evidence suggests that distant populations produce hybrids with reproductive...
ERIC Educational Resources Information Center
Hodge, N. J.
This autoinstructional lesson can be used with health education and/or biology classes in a high school curriculum. It deals with the study of human development with emphasis on the female reproductive organs and cycles. The behavioral objectives are given, and the materials and equipment needed to gain these objectives are itemized. Fifteen…
The reproductive tract is a complex, integrated organ system with diverse embryology and unique sensitivity to prenatal environmental exposures that disrupt morphoregulatory processes and endocrine signaling. U.S. EPA’s in vitro high-throughput screening (HTS) database (ToxCastDB...
Phenology of perennial native grass below-ground axillary buds in the northern mixed-grass prairie
USDA-ARS?s Scientific Manuscript database
Vegetative reproduction from belowground bud banks is the primary driver of grassland systems. Despite the importance of vegetative reproduction, the timing of belowground bud recruitment is unknown for most dominant, perennial native grasses as is the relationship between bud development and envir...
Occupational exposure associated with reproductive dysfunction.
Kumar, Sunil
2004-01-01
Evidence suggestive of harmful effects of occupational exposure on the reproductive system and related outcomes has gradually accumulated in recent decades, and is further compounded by persistent environmental endocrine disruptive chemicals. These chemicals have been found to interfere with the function of the endocrine system, which is responsible for growth, sexual development and many other essential physiological functions. A number of occupations are being reported to be associated with reproductive dysfunction in males as well as in females. Generally, occupations involving the manufacture/or application of some of the persistent chemicals that are not easily degradable as well as bio-accumulative chemicals, occupations involving intensive exposure to heat and radiation, occupations involving the use of toxic solvents as well as toxic fumes are reported to be associated with reproductive dysfunction. Occupational exposure of males to various persistent chemicals have been reported to have male mediated adverse reproductive outcomes in the form of abortion, reduction in fertility etc. with inconclusive or limited evidence. Nevertheless, there is a need for more well designed studies in order to implicate any individual chemical having such effects as in most occupations workers are exposed to raw, intermediate and finished products and there are also several confounding factors associated with lifestyles responsible for reproductive dysfunction. There is an urgent need to look at indiscriminate use of persistent chemicals especially pesticides and persistent organic pollutants (POP's) as these chemicals enter the food chain also and could be potential for exposure during the critical period of development. It is also necessary to impart information, and to educate about the safe use of these chemicals, as a very sensitive reproduction issue is involved with exposure to these chemicals. Occupational exposures often are higher than environmental exposures, so that epidemiological studies should be conducted on these chemicals, on a priority basis, which are reported to have adverse effects on reproduction in the experimental system.
Herrler, Claudia; Bramesfeld, Anke; Brodowski, Marc; Prytherch, Helen; Marx, Irmgard; Nafula, Maureen; Richter-Aairijoki, Heide; Musyoka, Lucy; Marx, Michael; Szecsenyi, Joachim
2015-01-01
To develop a model aiming to improve the quality of services for reproductive health care in rural Kenya and designed to measure the quality of reproductive health services in such a way that allows these services to identify measures for improving their performance. The Integrated Quality Management System (IQMS) was developed on the basis of a pre-existing and validated model for quality promotion, namely the European Practice Assessment (EPA). The methodology for quality assessment and feedback of assessment results to the service teams was adopted from the EPA model. Quality assessment methodology included data assessment through staff, patient surveys and service visitation. Quality is assessed by indicators, and so indicators had to be developed that were appropriate for assessing reproductive health care in rural Kenya. A search of the Kenyan and international literature was conducted to identify potential indicators. These were then rated for their relevance and clarity by a panel of Kenyan experts. 260 indicators were rated as relevant and assigned to 29 quality dimensions and 5 domains. The implementation of IQMS in ten facilities showed that IQMS is a feasible model for assessing the quality of reproductive health services in rural Kenya. IQMS enables these services to identify quality improvement targets and necessary improvement measures. Both strengths and limitations of IQMS will be discussed. Copyright © 2015. Published by Elsevier GmbH.
Stress and the HPA Axis: Balancing Homeostasis and Fertility
Whirledge, Shannon
2017-01-01
An organism’s reproductive fitness is sensitive to the environment, integrating cues of resource availability, ecological factors, and hazards within its habitat. Events that challenge the environment of an organism activate the central stress response system, which is primarily mediated by the hypothalamic–pituitary–adrenal (HPA) axis. The regulatory functions of the HPA axis govern the cardiovascular and metabolic system, immune functions, behavior, and reproduction. Activation of the HPA axis by various stressors primarily inhibits reproductive function and is able to alter fetal development, imparting a biological record of stress experienced in utero. Clinical studies and experimental data indicate that stress signaling can mediate these effects through direct actions in the brain, gonads, and embryonic tissues. This review focuses on the mechanisms by which stress activation of the HPA axis impacts fertility and fetal development. PMID:29064426
Fajans, Peter; Simmons, Ruth; Ghiron, Laura
2006-03-01
Public sector health systems that provide services to poor and marginalized populations in developing countries face great challenges. Change associated with health sector reform and structural adjustment often leaves these already-strained institutions with fewer resources and insufficient capacity to relieve health burdens. The Strategic Approach to Strengthening Reproductive Health Policies and Programs is a methodological innovation developed by the World Health Organization and its partners to help countries identify and prioritize their reproductive health service needs, test appropriate interventions, and scale up successful innovations to a subnational or national level. The participatory, interdisciplinary, and country-owned process can set in motion much-needed change. We describe key features of this approach, provide illustrations from country experiences, and use insights from the diffusion of innovation literature to explain the approach's dissemination and sustainability.
Shifting from clonal to sexual reproduction in aphids: physiological and developmental aspects.
Le Trionnaire, Gaël; Hardie, Jim; Jaubert-Possamai, Stéphanie; Simon, Jean-Christophe; Tagu, Denis
2008-08-01
Developmental biology is one of the fastest growing and fascinating research fields in life sciences. Among the wide range of embryonic development, a fundamental difference exists between organisms with sexual or asexual development. Aphids are unusual organisms which display alternative pathways of sexual and asexual development, the orientation of the pathway being determined by environmental conditions. These insects offer an adapted system in which to study developmental plasticity, because a side-by-side comparison of sexual and asexual development can be made in individuals with the same genotype. In this review, we describe the developmental mechanisms that have evolved in aphids for alternative sexual and asexual reproduction. In particular, we discuss how environmental cues orientate the reproductive mode of aphids from signal perception to endocrine regulation, and propose a comparative analysis of sexual and asexual gametogenesis and embryogenesis, which has been possible due to the development of molecular methods. As a result of the recent development of genomic resources in aphids, we expect these species will permit major advances in the study of the genomic basis underlying the choice of developmental fate and multiple reproduction strategies.
Some assembly required: evolutionary and systems perspectives on the mammalian reproductive system.
Mordhorst, Bethany R; Wilson, Miranda L; Conant, Gavin C
2016-01-01
In this review, we discuss the way that insights from evolutionary theory and systems biology shed light on form and function in mammalian reproductive systems. In the first part of the review, we contrast the rapid evolution seen in some reproductive genes with the generally conservative nature of development. We discuss directional selection and coevolution as potential drivers of rapid evolution in sperm and egg proteins. Such rapid change is very different from the highly conservative nature of later embryo development. However, it is not unique, as some regions of the sex chromosomes also show elevated rates of evolutionary change. To explain these contradictory trends, we argue that it is not reproductive functions per se that induce rapid evolution. Rather, it is the fact that biotic interactions, such as speciation events and sexual conflict, have no evolutionary endpoint and hence can drive continuous evolutionary changes. Returning to the question of sex chromosome evolution, we discuss the way that recent advances in evolutionary genomics and systems biology and, in particular, the development of a theory of gene balance provide a better understanding of the evolutionary patterns seen on these chromosomes. We end the review with a discussion of a surprising and incompletely understood phenomenon observed in early embryos: namely the Warburg effect, whereby glucose is fermented to lactate and alanine rather than respired to carbon dioxide. We argue that evolutionary insights, from both yeasts and tumor cells, help to explain the Warburg effect, and that new metabolic modeling approaches are useful in assessing the potential sources of the effect.
Figueira, Marília I; Cardoso, Henrique J; Correia, Sara; Maia, Cláudio J; Socorro, Sílvia
2017-10-01
The tyrosine kinase receptor c-KIT and its ligand, the stem cell factor (SCF) are expressed in several tissues of male and female reproductive tract, playing an important role in the regulation of basic biological processes. The activation of c-KIT by SCF controls, cell survival and death, cell differentiation and migration. Also, the SCF/c-KIT system has been implicated in carcinogenesis of reproductive tissues due to its altered expression pattern or overactivation in consequence of gain-of-functions mutations. Over the years, it has also been shown that hormones, the primary regulators of reproductive function and causative agents in the case of hormone-dependent cancers, are also able to control the SCF/c-KIT tissue levels. Therefore, it is liable to suppose that disturbed SCF/c-KIT expression driven by (de)regulated hormone actions can be a relevant step towards carcinogenesis. The present review describes the SCF and c-KIT expression in cancers of reproductive tissues, discussing the implications of the hormonal regulation of the SCF/c-KIT system in cancer development. Understanding the relationship between hormonal imbalance and the SCF/c-KIT expression and activity would be relevant in the context of novel therapeutic approaches in reproductive cancers. Copyright © 2017 Elsevier B.V. All rights reserved.
Leite, Gabriel Adan Araújo; Figueiredo, Thamiris Moreira; Sanabria, Marciana; Dias, Ana Flávia Mota Gonçalves; Silva, Patrícia Villela E; Martins Junior, Airton da Cunha; Barbosa Junior, Fernando; Kempinas, Wilma De Grava
2017-10-01
Dyslipidemias are occurring earlier in the population due to the increase of obesity and bad eating habits. Rosuvastatin inhibits the enzyme HMG-CoA reductase, decreasing total cholesterol. Ascorbic acid is an important antioxidant compound for male reproductive system. This study aimed to evaluate whether ascorbic acid supplementation may prevent the reproductive damage provoked by rosuvastatin administration at prepuberty. Male pups were distributed into six experimental groups that received saline solution 0.9%, 3 or 10mg/kg/day of rosuvastatin, 150mg/day of ascorbic acid, or 150mg/day of ascorbic acid associated with 3 or 10mg/kg/day of rosuvastatin from post-natal day (PND) 23 until PND53. Rosuvastatin-treated groups showed delayed puberty installation, androgen depletion and impairment on testicular and epididymal morphology. Ascorbic acid partially prevented these reproductive damages. In conclusion, rosuvastatin exposure is a probable risk to reproductive development and ascorbic acid supplementation may be useful to prevent the reproductive impairment of rosuvastatin exposure. Copyright © 2017 Elsevier Inc. All rights reserved.
Reproductive rights approach to reproductive health in developing countries.
Pillai, Vijayan K; Gupta, Rashmi
2011-01-01
Research on reproductive health in developing countries focuses mostly on the role of economic development on various components of reproductive health. Cross-sectional and empirical research studies in particular on the effects of non-economic factors such as reproductive rights remain few and far between. This study investigates the influence of two components of an empowerment strategy, gender equality, and reproductive rights on women's reproductive health in developing countries. The empowerment strategy for improving reproductive health is theoretically situated on a number of background factors such as economic and social development. Cross-national socioeconomic and demographic data from a number of international organizations on 142 developing countries are used to test a model of reproductive rights and reproductive health. The findings suggest that both economic and democratic development have significant positive effects on levels of gender equality. The level of social development plays a prominent role in promoting reproductive rights. It is found that reproductive rights channel the influences of social structural factors and gender equality on reproductive health.
Nikpour, Maryam; Tirgar, Aram; Ebadi, Abbas; Ghaffari, Fatemeh; Firouzbakht, Mojgan; Hajiahmadi, Mahmod
2018-02-06
Although shift works is a certain treat for female reproductive health, but currently, there is no standardized instrument for measuring reproductive health among female shift workers. This study aims to develop and evaluate the psychometric properties of a Women Shift Workers' Reproductive Health Questionnaire (WSW-RHQ). This is a sequential exploratory mixed-method study with a qualitative and a quantitative phase. In the qualitative phase, semi-structured interviews will be held with female shift workers who live in Mazandaran Province, Iran, additionally, the literature review will be performed by searching electronic databases. Sampling will be done in different workplaces and with maximum variation respecting female shift workers' age and job and educational and different economic situation. Interview data will be analyzed using conventional content analysis and then, the primary item pool for the questionnaire will be developed. In the quantitative phase, we will evaluate the psychometric properties of the questionnaire, i.e. its face, content, construct as well as reliability via the internal consistency, stability. Finally, a scoring system will be developed for the questionnaire. The development of WSW-RHQ will facilitate the promotion and implementation of reproductive health interventions and assessment of their effectiveness. Other scholars can cross-culturally adapt and use the questionnaire according to their immediate contexts.
A critical evaluation of developmental and reproductive toxicology in nonhuman primates.
Faqi, Ali S
2012-02-01
The nonhuman primates (NHPs) are used in many areas of biomedical research where their similarities to humans make them exclusively valuable animal models. The use of NHPs in pre-clinical testing is expected to increase due to the increase in the development of biological compounds for therapeutic uses. The regulatory agencies around the world including Food and Drug Administration (FDA) generally requires developmental and reproductive toxicity (DART) testing of all new drugs to be used by women of childbearing age or men of reproductive potential. NHPs are most frequently used for DART testing when commonly used rodents and/or rabbits are not pharmacologically relevant species. Animal studies are unique in that assessment of reproduction and development as DART studies are not performed in controlled clinical trials; therefore, pre-clinical safety assessment forms the basis for risk assessment for marketed drug products. This paper provides a critical evaluation of developmental and reproductive toxicity studies in NHPs. The manuscript will focus on species selection, limitation of International Conference for Harmonization stages (A-F) using NHPs as a test system, study designs, logistical/technical challenges, and strength, and limitations. It will also pinpoint confounding factors inherent to the test system that may complicate the interpretation of the NHP DART data.
Genome constraint through sexual reproduction: application of 4D-Genomics in reproductive biology.
Horne, Steven D; Abdallah, Batoul Y; Stevens, Joshua B; Liu, Guo; Ye, Karen J; Bremer, Steven W; Heng, Henry H Q
2013-06-01
Assisted reproductive technologies have been used to achieve pregnancies since the first successful test tube baby was born in 1978. Infertile couples are at an increased risk for multiple miscarriages and the application of current protocols are associated with high first-trimester miscarriage rates. Among the contributing factors of these higher rates is a high incidence of fetal aneuploidy. Numerous studies support that protocols including ovulation-induction, sperm cryostorage, density-gradient centrifugation, and embryo culture can induce genome instability, but the general mechanism is less clear. Application of the genome theory and 4D-Genomics recently led to the establishment of a new paradigm for sexual reproduction; sex primarily constrains genome integrity that defines the biological system rather than just providing genetic diversity at the gene level. We therefore propose that application of assisted reproductive technologies can bypass this sexual reproduction filter as well as potentially induce additional system instability. We have previously demonstrated that a single-cell resolution genomic approach, such as spectral karyotyping to trace stochastic genome level alterations, is effective for pre- and post-natal analysis. We propose that monitoring overall genome alteration at the karyotype level alongside the application of assisted reproductive technologies will improve the efficacy of the techniques while limiting stress-induced genome instability. The development of more single-cell based cytogenomic technologies are needed in order to better understand the system dynamics associated with infertility and the potential impact that assisted reproductive technologies have on genome instability. Importantly, this approach will be useful in studying the potential for diseases to arise as a result of bypassing the filter of sexual reproduction.
Sidze, Estelle M; Beekink, Erik; Maina, Beatrice W
2015-05-05
Universal access to reproductive health services entails strengthening health systems, but requires significant resource commitments as well as efficient and effective use of those resources. A number of international organizations and governments in developing countries are putting efforts into tracking the flow of health resources in order to inform resource mobilization and allocation, strategic planning, priority setting, advocacy and general policy making. The UNFPA/NIDI-led Resource Flows Project ("The UNFPA/NIDI RF Project") has conducted annual surveys since 1997 to monitor progress achieved by developing countries in implementing reproductive health financial targets. This commentary summarizes the Project experiences and challenges in gathering data on allocation of resources for reproductive health at the domestic level in sub-Saharan African countries. One key lesson learnt from the Project experience is the need for strengthening tracking mechanisms in sub-Saharan African countries and making information on reproductive health resources and expenditures available, in particular the private sector resources.
Human leukocyte antigen-G in the male reproductive system and in seminal plasma.
Larsen, Margit Hørup; Bzorek, Michael; Pass, Malene B; Larsen, Lise Grupe; Nielsen, Mette Weidinger; Svendsen, Signe Goul; Lindhard, Anette; Hviid, Thomas Vauvert F
2011-12-01
One of the non-classical human leukocyte antigen (HLA) class Ib proteins, HLA-G, is believed to exert important immunoregulatory functions, especially during pregnancy. The presence of HLA protein in paternal seminal fluid has been suggested to have an influence on the risk of developing pre-eclampsia. We have investigated whether HLA-G protein is present in human seminal plasma and in different tissue samples of the male reproductive system. Western blot technique and a soluble HLA-G (sHLA-G) assay were used to detect sHLA-G in human seminal plasma samples. Immunohistochemical staining was performed on paraffin-embedded tissue samples. We detected sHLA-G protein in seminal plasma, and HLA-G expression in normal testis and in epididymal tissue of the male reproductive system but not in the seminal vesicle. Furthermore, the results indicated a weak expression of HLA-G in hyperplastic prostatic tissue. In summary, several of the findings reported in this study suggest an immunoregulatory role of HLA-G in the male reproductive system and in seminal plasma.
Glycobiology of Reproductive Processes in Marine Animals: The State of the Art
Gallo, Alessandra; Costantini, Maria
2012-01-01
Glycobiology is the study of complex carbohydrates in biological systems and represents a developing field of science that has made huge advances in the last half century. In fact, it combines all branches of biomedical research, revealing the vast and diverse forms of carbohydrate structures that exist in nature. Advances in structure determination have enabled scientists to study the function of complex carbohydrates in more depth and to determine the role that they play in a wide range of biological processes. Glycobiology research in marine systems has primarily focused on reproduction, in particular for what concern the chemical communication between the gametes. The current status of marine glycobiology is primarily descriptive, devoted to characterizing marine glycoconjugates with potential biomedical and biotechnological applications. In this review, we describe the current status of the glycobiology in the reproductive processes from gametogenesis to fertilization and embryo development of marine animals. PMID:23247316
Saving and Reproduction of Human Motion Data by Using Haptic Devices with Different Configurations
NASA Astrophysics Data System (ADS)
Tsunashima, Noboru; Yokokura, Yuki; Katsura, Seiichiro
Recently, there has been increased focus on “haptic recording” development of a motion-copying system is an efficient method for the realization of haptic recording. Haptic recording involves saving and reproduction of human motion data on the basis of haptic information. To increase the number of applications of the motion-copying system in various fields, it is necessary to reproduce human motion data by using haptic devices with different configurations. In this study, a method for the above-mentioned haptic recording is developed. In this method, human motion data are saved and reproduced on the basis of work space information, which is obtained by coordinate transformation of motor space information. The validity of the proposed method is demonstrated by experiments. With the proposed method, saving and reproduction of human motion data by using various devices is achieved. Furthermore, it is also possible to use haptic recording in various fields.
Reproductive toxicity evaluation of dietary butyl benzyl phthalate (BBP) in rats.
Tyl, Rochelle W; Myers, Christina B; Marr, Melissa C; Fail, Patricia A; Seely, John C; Brine, Dolores R; Barter, Robert A; Butala, John H
2004-01-01
Butyl benzyl phthalate (BBP) was administered in the diet at 0, 750, 3750, and 11,250 ppm ad libitum to 30 rats per sex per dose for two offspring generations, one litter/breeding pair/generation, through weaning of F2 litters. Adult F0 systemic toxicity and adult F1 systemic and reproductive toxicity were present at 11,250 ppm (750 mg/kg per day). At 11,250 ppm, there were reduced F1 and F2 male anogenital distance (AGD) and body weights/litter during lactation, delayed acquisition of puberty in F1 males and females, retention of nipples and areolae in F1 and F2 males, and male reproductive system malformations. At 3750 ppm (250 mg/kg per day), only reduced F1 and F2 offspring male AGD was present. There were no effects on parents or offspring at 750 ppm (50 mg/kg per day). The F1 parental systemic and reproductive toxicity no observable adverse effect level (NOAEL) was 3750 ppm. The offspring toxicity NOAEL was 3750 ppm. The offspring toxicity no observable effect level (NOEL) was 750 ppm, based on the presence of reduced AGD in F1 and F2 males at birth at 3750 ppm, but no effects on reproductive development, structures, or functions.
Involvement of opioid peptides in the regulation of reproduction in the prawn Penaeus indicus
NASA Astrophysics Data System (ADS)
Sreenivasula Reddy, P.
The possible involvement of an endogenous opioid system in the regulation of ovarian development in the prawn Penaeus indicus was investigated. Injection of leucine-enkephalin significantly increased the ovarian index and oocyte diameter in a dose-dependent manner. In contrast, injection of methionine-enkephalin significantly decreased the ovarian index and oocyte diameters. These results provide evidence to support the hypothesis that an opioid system is involved in the regulation of reproduction in crustaceans.
Young, C D; Schrick, F N; Pohler, K G; Saxton, A M; Di Croce, F A; Roper, D A; Wilkerson, J B; Edwards, J L
2017-07-01
We developed a reproductive tract size and position score (SPS) system as a reproductive management tool to identify lactating dairy cows with decreased fertility. This system, relying solely on transrectal palpation, considers the size (cervical and uterine) and position of the reproductive tract relative to the pelvis. Cows undergoing pre-breeding exams were identified as having reproductive tracts that were small (SPS1), medium (SPS2), or large (SPS3). Cows designated SPS1 had small and compact uterine horns that rested within the pelvic cavity; SPS2 cows had reproductive tracts that were intermediate in cervical and uterine horn diameter, with longer uterine horns resting partially outside the pelvic cavity; and SPS3 cows had reproductive tracts that were larger and rested mostly outside the pelvic cavity. Cows that were SPS1 had a higher rate of pregnancy per artificial insemination (43.3 ± 3.7%) than cows that were SPS2 (36.9 ± 3.6%) or SPS3 (27.7 ± 4.3%). The percentage of cows with an SPS2 score differed in pregnancies per artificial insemination compared with SPS3 cows. The average days in milk was similar for SPS1, SPS2, and SPS3 cows (104.3 ± 3.5, 98.4 ± 3.4, and 94.7 ± 7.7, respectively). Ultrasound measurements of the uterine horn and cervical diameter, and length measurements of the uterine horns, cervix, and vagina confirmed differences among the SPS groups derived by transrectal palpation. The ease with which transrectal palpation can be used to determine the size and position of the reproductive tract attests to the relevance and usefulness of this scoring system to identify less fertile lactating dairy cows. The ability to do so with ease provides an opportunity to make economically relevant management decisions and maximize reproductive efficiency in a given herd. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Prenatal testosterone exposure worsen the reproductive performance of male rat at adulthood.
Ramezani Tehrani, Fahimeh; Noroozzadeh, Mahsa; Zahediasl, Saleh; Ghasemi, Asghar; Piryaei, Abbas; Azizi, Fereidoun
2013-01-01
The reproductive system is extremely susceptible to environmental insults, for example exogenous steroids during gestational development and differentiation. Experimental induction of androgen excess during prenatal life in female animal models reprograms their reproductive physiology, however the fetal programming of the male reproductive system by androgen excess has not been well studied. We aimed to determine the effect of prenatal exposure of two different doses of testosterone on different gestational days, on the male reproductive system using a rat model. Sixteen pregnant rats were randomly divided into two experimental groups and two control groups. Experimental group І were subcutaneously injected with 3 mg free testosterone on gestational days 16-19 and its controls received solvent for that time; experimental group П were subcutaneously injected with 20 mg free testosterone on day 20 of gestational period and its controls received solvent at the same time. The reproductive system morphology and function of 32 male offspring of these study groups were compared at days 6-30-60 of age and after puberty. The anogenital distance of the male offspring of both experimental groups had no significant differences on the different days of measurement, compared with controls. In the offspring of experimental group І, the testes weight, number of Sertoli, Spermatocyte and Spermatid cells, sperm count and motility and the serum concentration of testosterone after puberty were significantly decreased; except for reduction of sperm motility (p< 0.01), the other effects were not observed in the offspring of experimental group ІІ. In summary, our data show that prenatal exposure of male rat fetuses to excess testosterone disrupted reproductive function, an effect highly dependent on the time, duration and level of exposure. It seems that the reproductive system in individuals exposed to high levels of androgens during fetal life should be evaluated at puberty and likely to be treated.
Prenatal Testosterone Exposure Worsen the Reproductive Performance of Male Rat at Adulthood
Ramezani Tehrani, Fahimeh; Noroozzadeh, Mahsa; Zahediasl, Saleh; Ghasemi, Asghar; Piryaei, Abbas; Azizi, Fereidoun
2013-01-01
The reproductive system is extremely susceptible to environmental insults, for example exogenous steroids during gestational development and differentiation. Experimental induction of androgen excess during prenatal life in female animal models reprograms their reproductive physiology, however the fetal programming of the male reproductive system by androgen excess has not been well studied. We aimed to determine the effect of prenatal exposure of two different doses of testosterone on different gestational days, on the male reproductive system using a rat model. Sixteen pregnant rats were randomly divided into two experimental groups and two control groups. Experimental group І were subcutaneously injected with 3 mg free testosterone on gestational days 16-19 and its controls received solvent for that time; experimental group П were subcutaneously injected with 20 mg free testosterone on day 20 of gestational period and its controls received solvent at the same time. The reproductive system morphology and function of 32 male offspring of these study groups were compared at days 6-30-60 of age and after puberty. The anogenital distance of the male offspring of both experimental groups had no significant differences on the different days of measurement, compared with controls. In the offspring of experimental group І, the testes weight, number of Sertoli, Spermatocyte and Spermatid cells, sperm count and motility and the serum concentration of testosterone after puberty were significantly decreased; except for reduction of sperm motility (p< 0.01), the other effects were not observed in the offspring of experimental group ІІ. In summary, our data show that prenatal exposure of male rat fetuses to excess testosterone disrupted reproductive function, an effect highly dependent on the time, duration and level of exposure. It seems that the reproductive system in individuals exposed to high levels of androgens during fetal life should be evaluated at puberty and likely to be treated. PMID:23967236
Reproductive rights approach to reproductive health in developing countries
Pillai, Vijayan K.; Gupta, Rashmi
2011-01-01
Background Research on reproductive health in developing countries focuses mostly on the role of economic development on various components of reproductive health. Cross-sectional and empirical research studies in particular on the effects of non-economic factors such as reproductive rights remain few and far between. Objective This study investigates the influence of two components of an empowerment strategy, gender equality, and reproductive rights on women's reproductive health in developing countries. The empowerment strategy for improving reproductive health is theoretically situated on a number of background factors such as economic and social development. Design Cross-national socioeconomic and demographic data from a number of international organizations on 142 developing countries are used to test a model of reproductive rights and reproductive health. Results The findings suggest that both economic and democratic development have significant positive effects on levels of gender equality. The level of social development plays a prominent role in promoting reproductive rights. It is found that reproductive rights channel the influences of social structural factors and gender equality on reproductive health. PMID:22184501
TRIENNIAL REPRODUCTION SYMPOSIUM: Developmental programming of fertility.
Reynolds, L P; Vonnahme, K A
2016-07-01
The 2015 Triennial Reproduction Symposium focused on developmental programming of fertility. The topics covered during the morning session included the role of the placenta in programming of fetal growth and development, effects of feeding system and level of feeding during pregnancy on the annual production cycle and lifetime productivity of heifer offspring, effects of litter size and level of socialization postnatally on reproductive performance of pigs, effects of postnatal dietary intake on maturation of the hypothalamic-pituitary-gonadal axis and onset of puberty in heifers, effects of housing systems on growth performance and reproductive efficiency of gilts, and effects of energy balance on sexual differentiation in rodent models. The morning session concluded with presentation of the American Society of Animal Science L. E. Casida Award for Excellence in Graduate Education to Dr. Michael Smith from the University of Missouri, Columbia, who shared his philosophy of graduate education. The afternoon session included talks on the role of epigenetic modifications in developmental programming and transgenerational inheritance of reproductive dysfunction, effects of endocrine disrupting compounds on fetal development and long-term physiology of the individual, and potential consequences of real-life exposure to environmental contaminants on reproductive health. The symposium concluded with a summary talk and the posing of 2 questions to the audience. From an evolutionary standpoint, programming and epigenetic events must be adaptive; when do they become maladaptive? If there are so many environmental factors that induce developmental programming, are we doomed, and if not, what is or are the solution or solutions?
Burke, C R; Verkerk, G A
2010-01-01
The New Zealand (NZ) economy and its dairy industry are sensitive to global consumer perception of farming practices used to generate milk products because milk exports account for > 25% of national export earnings and > 90% of milk produced is exported as products. Astute management of product image and market risk is, therefore, important for the viability of the industry and country. More than 95% of milk produced in NZ comes from strictly seasonal, pasture-based systems, with associated constraints on reproductive performance. Increasing herd sizes, operational changes and genetic selection priorities have further challenged dairy farmers to achieve optimal levels of herd fertility. Reproductive management practices have developed to address the need to maintain a 365-day inter-calving interval, essentially through maximizing the number of cyclic cows during the breeding period and minimizing the duration of the seasonal calving period. Aspects of the hormonal interventions developed and routinely used to achieve these objectives have been the subject of product quality and market risk concerns forcing the industry to explore alternative ways of achieving reproductive performance goals. One approach has been to exploit the inherently high level of fertility in NZ dairy herds. This approach has seen the inclusion of fertility-related traits in the national genetic evaluation system to prevent further decline in genetic fertility. More recently, a nationally coordinated extension program has been adopted to support farmers and their advisors to identify, prioritize and improve on key management areas for incremental gains in herd reproductive performance. Advances in automation and bio-sensing are yet to make a significant impact, but remain potentially valuable additions in supporting the dairy farmer to manage the areas having the largest effects on reproductive performance.
Bai, Jun; Wu, Ke-Ming; Gao, Ran-Ran
2018-03-01
In the theory of traditional Chinese medicine(TCM) that "kidney storing essence and governing reproduction", reproductive essence is an important part of the kidney essence and acts as the original material of offspring embryos. Sperm, oocyte and zygote should be all included in the range of reproductive essence. Ovum is the essence of reproduction from inborn. The follicles maturation depends on the quality of oocyte and the vigor of kidney essence. Meanwhile, discharge of mature ovum relies on the stimulation and promotion by kidney Qi. Autophagy almost exists in different cells stages and all various of mammalian cells. Many studies have found that autophagy not only participates in the formation of follicles, but also in every phase of the follicles development, and is involved in the occurrence and development of ovarian diseases. Recently, more and more scholars believe that autophagy is a new field to explore the microcosmic relationship between autophagy and TCM. Kidney-nourishing TCM could promote follicular growth and improve variety clinical symptoms by inhibiting the apoptosis of ovarian granulosa cells and reducing follicular atresia. Meanwhile, apoptosis of ovarian granulosa cells is closely related to autophagy of ovarian granulosa cells. In order to provide some theoretical foundation for kidney-nourishing therapy's promoting effect on follicular growth and improving effect on ovarian function, also to further explore the molecular mechanism of kidney-nourishing medicine in promoting follicular development, this paper would explain the microcosmic relationship between autophagy and follicular development based on the theory of "kidney governing reproduction". All of these would be of great significance to prevent and intervene the diseases of reproductive system timely and effectively. Copyright© by the Chinese Pharmaceutical Association.
Ethical and legal aspects in medically assisted human reproduction in Romania.
Ioan, Beatrice; Astarastoae, Vasile
2008-01-01
Up to the present, there have not been any specific norms regarding medically assisted human reproduction in Romanian legislation. Due to this situation the general legislation regarding medical assistance (law no. 95/2006, regarding the Reform in Health Care System), the Penal and Civil law and the provisions of the Code of Deontology of the Romanian College of Physicians are applied to the field of medically assisted human reproduction. By analysing the ethical and legal conflicts regarding medically assisted human reproduction in Romania, some characteristics cannot be set apart because they derive from religious, cultural and socio-economic aspects. In this article the authors identify the development stages of medically assisted human reproduction in Romania, beginning from these characteristics and insisting upon the failure of the legal system in this specific field. The authors consider that the law regarding medically assisted human reproduction cannot be effective because it did not take into account the ethical and cultural aspects that might appear. Furthermore, in this framework of the legal process, no public debate involving the representatives of civil society was undertaken although the Council of Europe Oviedo Convention approved by our country according to law no. 17/2001 stipulated exactly this working method.
Ageing and inflammation in the male reproductive tract.
Frungieri, M B; Calandra, R S; Bartke, A; Matzkin, M E
2018-05-08
Ageing is usually characterised by a mild chronic proinflammatory state. Despite the tight association between both processes, the phenomenon has recently been termed inflammageing. Inflammation in the male reproductive tract is frequently linked with bacterial or virus infections but also with a broad range of noninfectious processes. Prostatitis, epididymitis and orchitis, among others, can lead to infertility. However, in spite of the inflammation theory of disease, chronic inflammation in male urogenital system does not always cause symptoms. With advancing age, inflammatory processes are commonly observed in the male reproductive tract. Nevertheless, the incidence of inflammation in reproductive organs and ducts varies greatly among elderly men. Inflammageing is considered a predictor of pathogenesis and the development of age-related diseases. This article briefly summarises the current state of knowledge on inflammageing in the male reproductive tract. Yet, the precise aetiology of inflammageing in the male urogenital system, and its potential contribution not only to infertility but most importantly to adverse health outcomes remains almost unknown. Thus, further investigations are required to elucidate the precise cross-links between inflammation and male reproductive senescence, and to establish the impact of anti-inflammatory drug treatments on elder men's general health status. © 2018 Blackwell Verlag GmbH.
Bajaj, Vijay Kumar; Gupta, Radhey S
2013-08-01
Male contraceptive development in the present scenario is most viable aspect of research due to uncontrolled population growth in the world. In this respect investigators are busy to find out a safe male contraceptive drug. Researchers have started their finding for a suitable drug from natural sources because these are safe and easily acceptable for common man, most of natural sources are plants and their products. In this review 137 plants and their effects on reproduction and reproductive physiology are summarized. Some of them have intense effect on male reproductive system and do not produce any side effects. Reproductive toxicological studies are also important aspects of these kinds of researches, so it is important that drugs are safe and widely acceptable. An ideal male contraceptive can influence semen, testes, hormone level, accessory reproductive organs and general physiology of animals and produced some alterations. Many plants in this review are showing antifertility as well as antispermatogenic effects, so these may be used for further study for contraceptives development but it is important to find out the mechanism of reaction and further laboratory and clinical research on some plants are needed for final male contraceptive drug development. In conclusion this review will help for finding suitable plant products for male contraceptive clinical and laboratory studies.
Metabolic control of oocyte development: linking maternal nutrition and reproductive outcomes
Liu, Honglin; Gu, Xi; Boots, Christina; Moley, Kelle H.
2015-01-01
Obesity, diabetes, and related metabolic disorders are major health issues worldwide. As the epidemic of metabolic disorders continues, the associated medical comorbidities, including the detrimental impact on reproduction, increase as well. Emerging evidence suggests that the effects of maternal nutrition on reproductive outcomes are likely to be mediated, at least in part, by oocyte metabolism. Well-balanced and timed energy metabolism is critical for optimal development of oocytes. To date, much of our understanding of oocyte metabolism comes from the effects of extrinsic nutrients on oocyte maturation. In contrast, intrinsic regulation of oocyte development by metabolic enzymes, intracellular mediators, and transport systems is less characterized. Specifically, decreased acid transport proteins levels, increased glucose/lipid content and elevated reactive oxygen species in oocytes have been implicated in meiotic defects, organelle dysfunction and epigenetic alteration. Therefore, metabolic disturbances in oocytes may contribute to the diminished reproductive potential experienced by women with metabolic disorders. In-depth research is needed to further explore the underlying mechanisms. This review also discusses several approaches for metabolic analysis. Metabolomic profiling of oocytes, the surrounding granulosa cells, and follicular fluid will uncover the metabolic networks regulating oocyte development, potentially leading to the identification of oocyte quality markers and prevention of reproductive disease and poor outcomes in offspring. PMID:25280482
Peso, Marianne; Even, Naïla; Søvik, Eirik; Naeger, Nicholas L; Robinson, Gene E; Barron, Andrew B
2016-02-01
Reproductive and behavioural specialisations characterise advanced social insect societies. Typically, the honey bee (Apis mellifera) shows a pronounced reproductive division of labour between worker and queen castes, and a clear division of colony roles among workers. In a queenless condition, however, both of these aspects of social organisation break down. Queenless workers reproduce, forage and maintain their colony operating in a manner similar to communal bees, rather than as an advanced eusocial group. This plasticity in social organisation provides a natural experiment for exploring physiological mechanisms of division of labour. We measured brain biogenic amine (BA) levels and abdominal fat body vitellogenin gene expression levels of workers in queenright and queenless colonies. Age, ovary activation and social environment influenced brain BA levels in honey bees. BA levels were most influenced by ovary activation state in queenless bees. Vitellogenin expression levels were higher in queenless workers than queenright workers, but in both colony environments vitellogenin expression was lower in foragers than non-foragers. We propose this plasticity in the interacting signalling systems that influence both reproductive and behavioural development allows queenless workers to deviate significantly from the typical worker bee reaction norm and develop as reproductively active behavioural generalists.
Ovarian function and reproductive senescence in the rat: role of ovarian sympathetic innervation.
Cruz, Gonzalo; Fernandois, Daniela; Paredes, Alfonso H
2017-02-01
Successful reproduction is the result of a myriad interactions in which the ovary and the ovarian follicular reserve play a fundamental role. At present, women who delay maternity until after 30 years of age have a decreased fertility rate due to various causes, including damaged follicles and a reduction in the reserve pool of follicles. Therefore, the period just prior to menopause, also known as the subfertile period, is important. The possibility of modulating the follicular pool and the health of follicles during this period to improve fertility is worth exploring. We have developed an animal model to study the ovarian ageing process during this subfertile period to understand the mechanisms responsible for reproductive senescence. In the rat model, we have shown that the sympathetic nervous system participates in regulating the follicular development during ovarian ageing. This article reviews the existing evidence on the presence and functional role of sympathetic nerve activity in regulating the follicular development during ovarian ageing, with a focus on the subfertile period.Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/153/2/R61/suppl/DC1. © 2017 Society for Reproduction and Fertility.
Socioeconomic and Reproductive Health Outcomes of Female Genital Mutilation.
Refaei, Mansoureh; Aghababaei, Soodabeh; Pourreza, Abolghasem; Masoumi, Seyedeh Zahra
2016-11-01
Female genital mutilation (FGM) is one of the important aspects of reproductive health. The economic, social and health consequences of FGM threaten the achievement of sustainable development goals. The purpose of this study was to assess the economic, social and reproductive health consequences of FGM from the perspective of individual, family, community and health system. In this study, we reviewed 1536 articles from 1979 to 2015. Fifty-one studies were directly related to our goal. Research papers, review articles, case studies and books on the research topic were used. The results of this review showed that most studies on FGM, have investigated health complications of FGM, and few studies have addressed its socioeconomic aspects. The complications from the FGM can impose a significant economic burden on individuals, society and health system. Social consequences of FGM are more irritating than health consequences, so to tackle this practice; its social aspects should be more emphasized. Significant short and long term consequences of FGM threaten women's reproductive health; Reproductive health is one of the essential prerequisites of sustainable development. Sustainable development will be achieved if women are healthy. This practice can threaten achieving sustainable development. In Iran, FGM is performed in some areas, but there are no official statistics about it and there has yet been no plan to deal with FGM. FGM is a form of social injustice which women suffer. Ending FGM requires a deep and long-term commitment. Knowing its consequences and its effects on individual, families, the health system and community will help supporters to continue fighting this practice. Any money spent on eliminating this harmful practice, compared with the costs of complications, would not be wasteful. It seems that further studies are needed to assess socioeconomic effects of FGM and the relationship between type of FGM and induced complications. Such studies will help policymakers to tackle this practice.
Rogiers, Suzy Y.; Clarke, Simon J.
2013-01-01
Heterogeneity in root-zone temperature both vertically and horizontally may contribute to the uneven vegetative and reproductive growth often observed across vineyards. An experiment was designed to assess whether the warmed half of a grapevine root zone could compensate for the cooled half in terms of vegetative growth and reproductive development. We divided the root system of potted Shiraz grapevines bilaterally and applied either a cool or a warm treatment to each half from budburst to fruit set. Shoot growth and inflorescence development were monitored over the season. Simultaneous cooling and warming of parts of the root system decreased shoot elongation, leaf emergence and leaf expansion below that of plants with a fully warmed root zone, but not to the same extent as those with a fully cooled root zone. Inflorescence rachis length, flower number and berry number after fertilization were smaller only in those vines exposed to fully cooled root zones. After terminating the treatments, berry enlargement and the onset of veraison were slowed in those vines that had been exposed to complete or partial root-zone cooling. Grapevines exposed to partial root-zone cooling were thus delayed in vegetative and reproductive development, but the inhibition was greater in those plants whose entire root system had been cooled. PMID:24244839
Neuroendocrine and behavioral implications of endocrine disrupting chemicals in quail
Ottinger, M.A.; Abdelnabi, M.A.; Henry, P.; McGary, S.; Thompson, N.; Wu, J.M.
2001-01-01
Studies in our laboratory have focused on endocrine, neuroendocrine, and behavioral components of reproduction in the Japanese quail. These studies considered various stages in the life cycle, including embryonic development, sexual maturation, adult reproductive function, and aging. A major focus of our research has been the role of neuroendocrine systems that appear to synchronize both endocrine and behavioral responses. These studies provide the basis for our more recent research on the impact of endocrine disrupting chemicals (EDCs) on reproductive function in the Japanese quail. These endocrine active chemicals include pesticides, herbicides, industrial products, and plant phytoestrogens. Many of these chemicals appear to mimic vertebrate steroids, often by interacting with steroid receptors. However, most EDCs have relatively weak biological activity compared to native steroid hormones. Therefore, it becomes important to understand the mode and mechanism of action of classes of these chemicals and sensitive stages in the life history of various species. Precocial birds, such as the Japanese quail, are likely to be sensitive to EDC effects during embryonic development, because sexual differentiation occurs during this period. Accordingly, adult quail may be less impacted by EDC exposure. Because there are a great many data available on normal development and reproductive function in this species, the Japanese quail provides an excellent model for examining the effects of EDCs. Thus, we have begun studies using a Japanese quail model system to study the effects of EDCs on reproductive endocrine and behavioral responses. In this review, we have two goals: first, to provide a summary of reproductive development and sexual differentiation in intact Japanese quail embryos, including ontogenetic patterns in steroid hormones in the embryonic and maturing quail. Second, we discuss some recent data from experiments in our laboratory in which EDCs have been tested in Japanese quail. The Japanese quail provides an excellent avian model for testing EDCs because this species has well-characterized reproductive endocrine and behavioral responses. Considerable research has been conducted in quail in which the effects of embryonic steroid exposure have been studied relative to reproductive behavior. Moreover, developmental processes have been studied extensively and include investigations of the reproductive axis, thyroid system, and stress and immune responses. We have conducted a number of studies, which have considered long-term neuroendocrine consequences as well as behavioral responses to steroids. Some of these studies have specifically tested the effects of embryonic steroid exposure on later reproductive function in a multigenerational context. A multigenerational exposure provides a basis for understanding potential exposure scenarios in the field. In addition, potential routes of exposure to EDCs for avian species are being considered, as well as differential effects due to stage of the life cycle at exposure to an EDC. The studies in our laboratory have used both diet and egg injection as modes of exposure for Japanese quail. In this way, birds were exposed to a specific dose of an EDC at a selected stage in development by injection. Alternatively, dietary exposure appears to be a primary route of exposure; therefore experimental exposure through the diet mimics potential field situations. Thus, experiments should consider a number of aspects of exposure when attempting to replicate field exposures to EDCs.
Spiegel, Carolina N; Bretas, Jorge A C; Peixoto, Alexandre A; Vigoder, Felipe M; Bruno, Rafaela V; Soares, Maurilio J
2013-01-01
The male reproductive system of insects can have several tissues responsible for the secretion of seminal fluid proteins (SFPs), such as testes, accessory glands, seminal vesicles, ejaculatory duct and ejaculatory bulb. The SFPs are transferred during mating and can induce several physiological and behavioral changes in females, such as increase in oviposition and decrease in sexual receptivity after copulation. The phlebotomine Lutzomyia longipalpis is the main vector of visceral leishmaniasis. Despite its medical importance, little is known about its reproductive biology. Here we present morphological aspects of the male L. longipalpis reproductive system by light, scanning and transmission electron microscopy, and compare the mating frequency of both virgin and previously mated females. The male L. longipalpis reproductive system is comprised by a pair of oval-shaped testes linked to a seminal vesicle by vasa deferentia. It follows an ejaculatory duct with an ejaculatory pump (a large bulb enveloped by muscles and associated to tracheas). The terminal endings of the vasa deferentia are inserted into the seminal vesicle by invaginations of the seminal vesicle wall, which is composed by a single layer of gland cells, with well-developed endoplasmic reticulum profiles and secretion granules. Our data suggest that the seminal vesicle acts both as a spermatozoa reservoir and as an accessory gland. Mating experiments support this hypothesis, revealing a decrease in mating frequency after copulation that indicates the effect of putative SFPs. Ultrastructural features of the L. longipalpis male seminal vesicle indicated its possible role as an accessory gland. Behavioral observations revealed a reduction in mating frequency of copulated females. Together with transcriptome analyses from male sandfly reproductive organs identifying ESTs encoding orthologs of SFPs, these data indicate the presence of putative L. longipalpis SFPs reducing sexual mating frequency of copulated females.
2003-04-01
TThe National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (CERHR) conducted an evaluation of the potential for di-n-butyl phthalate (DBP) to cause adverse effects on reproduction and development in humans. DBP is one of 7 phthalate chemicals evaluated by the NTP CERHR Phthalates Expert Panel. These phthalates were selected for evaluation because of high production volume, extent of human exposures, use in children's products, and/or published evidence of reproductive or developmental toxicity. Unlike many phthalates, DBP is not currently used as a plasticizer in polyvinyl chloride plastics. DBP is a component of latex adhesives and is used in cosmetics and other personal care products, as a plasticizer in cellulose plastics, and as a solvent for dyes. The results of this evaluation on DBP are published in a NTP-CERHR monograph which includes: 1) the NTP Brief, 2) the Expert Panel Report on the Reproductive and Developmental Toxicity of Di-n-Butyl Phthalate, and 3) public comments received on the Expert Panel Report. As stated in the NTP Brief, the NTP reached the following conclusions regarding the possible effects of exposure to DBP on human development and reproduction. First, although DBP could possibly affect human reproduction and development if exposures are sufficiently high, the NTP concludes that there is negligible concern for reproductive toxicity in exposed adults. Second, the NTP concludes that there is minimal concern for developmental effects when pregnant women are exposed to DBP levels estimated by the panel (2-10 mug/kg body weight/day). There is no direct evidence that exposure of people to DBP adversely affects reproduction or development, but studies reviewed by the expert panel show that oral exposure to high doses of DBP (>/=100 mg/kg body weight/day) may adversely affect the prenatal and early postnatal development in rodents. Finally, based on exposure estimates in women of reproductive age, the NTP concludes that there is some concern for DBP causing adverse effects to human development, particularly development of the male reproductive system. NTP-CERHR monographs are transmitted to federal and state agencies, interested parties, and the public and are available electronically in PDF format on the CERHR web site (http://cerhr.niehs.nih.gov) and in printed text or CD-ROM from the CERHR (National Institute of Environmental Health Sciences, P.O. Box 12233, MD EC-32, Research Triangle Park, NC; fax: 919-316-4511).
Electromagnetic field and brain development.
Kaplan, Suleyman; Deniz, Omur Gulsum; Önger, Mehmet Emin; Türkmen, Aysın Pınar; Yurt, Kıymet Kübra; Aydın, Işınsu; Altunkaynak, Berrin Zuhal; Davis, Devra
2016-09-01
Rapid advances in technology involve increased exposures to radio-frequency/microwave radiation from mobile phones and other wireless transmitting devices. As cell phones are held close to the head during talking and often stored next to the reproductive organs, studies are mostly focused on the brain. In fact, more research is especially needed to investigate electromagnetic field (EMF)'s effects on the central nervous system (CNS). Several studies clearly demonstrate that EMF emitted by cell phones could affect a range of body systems and functions. Recent work has demonstrated that EMF inhibit the formation and differentiation of neural stem cells during embryonic development and also affect reproductive and neurological health of adults that have undergone prenatal exposure. The aim of this review is to discuss the developing CNS and explain potential impacts of EMF on this system. Copyright © 2015 Elsevier B.V. All rights reserved.
Multigeneration Reproduction and Male Developmental Toxicity Studies on Atrazine in Rats
DeSesso, John M; Scialli, Anthony R; White, Tacey E K; Breckenridge, Charles B
2014-01-01
BACKGROUND Reproductive toxicity of Atrazine (ATR) was evaluated in two rat multigenerational studies. Development of male reproductive parameters was evaluated in separate studies after prenatal or postnatal exposure. METHODS In multigenerational studies, rats received dietary concentrations of 0, 10, 50, 100 or 500 ppm ATR. In separate studies in female rats, ATR was administered by gavage at 0, 1, 5, 25 or 125 mg/kg/day during pregnancy (GD6–21) or lactation (LD2–21). Plasma testosterone concentration, testicular and epididymal weights, and sperm counts were measured in male offspring on PND70 and 170. RESULTS In the multigenerational studies, parental systemic toxicity occurred at 500 ppm (38.7 mg/kg/day), but reproductive endpoints were unaffected. In the prenatal study, maternal toxicity and embryo-fetal mortality occurred at 125 mg/kg/day. In male offspring, testosterone levels and sperm counts were unaffected, although the percentage of abnormal sperm increased at 125 mg/kg/day (PND 70) and 25 mg/kg/day (PND170). In the postnatal study, maternal toxicity and reduced body weights of male offspring occurred at 125 mg/kg/day. Additionally, reduced testicular (PND70, PND170) and epididymal (PND70) weights and increased numbers of abnormal sperm (PND70, PND170) were seen, but no changes in plasma testosterone or sperm counts. CONCLUSIONS Dietary administration of ATR did not affect rat reproduction up to a parentally toxic dose of 38.7 mg/kg/day. Some effects on male reproductive system development occurred after high dose, bolus administration to dams, but doses were much higher than expected under normal use conditions. Thus, oral RfDs for ATR would be protective for reproductive effects PMID:24797874
Multigeneration reproduction and male developmental toxicity studies on atrazine in rats.
DeSesso, John M; Scialli, Anthony R; White, Tacey E K; Breckenridge, Charles B
2014-06-01
Reproductive toxicity of Atrazine (ATR) was evaluated in two rat multigenerational studies. Development of male reproductive parameters was evaluated in separate studies after prenatal or postnatal exposure. In multigenerational studies, rats received dietary concentrations of 0, 10, 50, 100 or 500 ppm ATR. In separate studies in female rats, ATR was administered by gavage at 0, 1, 5, 25 or 125 mg/kg/day during pregnancy (GD6-21) or lactation (LD2-21). Plasma testosterone concentration, testicular and epididymal weights, and sperm counts were measured in male offspring on PND70 and 170. In the multigenerational studies, parental systemic toxicity occurred at 500 ppm (38.7 mg/kg/day), but reproductive endpoints were unaffected. In the prenatal study, maternal toxicity and embryo-fetal mortality occurred at 125 mg/kg/day. In male offspring, testosterone levels and sperm counts were unaffected, although the percentage of abnormal sperm increased at 125 mg/kg/day (PND 70) and 25 mg/kg/day (PND170). In the postnatal study, maternal toxicity and reduced body weights of male offspring occurred at 125 mg/kg/day. Additionally, reduced testicular (PND70, PND170) and epididymal (PND70) weights and increased numbers of abnormal sperm (PND70, PND170) were seen, but no changes in plasma testosterone or sperm counts. Dietary administration of ATR did not affect rat reproduction up to a parentally toxic dose of 38.7 mg/kg/day. Some effects on male reproductive system development occurred after high dose, bolus administration to dams, but doses were much higher than expected under normal use conditions. Thus, oral RfDs for ATR would be protective for reproductive effects. © 2014 Wiley Periodicals, Inc.
First births with a simplified culture system for clinical IVF and embryo transfer.
Van Blerkom, Jonathan; Ombelet, Willem; Klerkx, Elke; Janssen, Mia; Dhont, Nathalie; Nargund, Geeta; Campo, Rudi
2014-03-01
This study reports the outcome results from a pilot clinical trial using a simplified laboratory method for human IVF. This system reproducibly generates de novo the atmospheric and culture conditions that support normal fertilization and preimplantation embryogenesis to the hatched blastocyst stage without the need for specialized medical-grade gases or equipment. Development from insemination to the hatched blastocyst stage occurs undisturbed in a completely closed system that enables timed performance assessments for embryo selection in situ that, in this study, involved single-embryo transfers on day 3. With the simplified culture system, 8/23 embryos implanted, one miscarried at 8weeks of gestation and seven healthy babies have been born. The methodology and results are discussed with regard to how this simplified system can be adopted worldwide to meet the growing need for accessible and affordable IVF. A common notion concerning the demographics of infertility is that it is largely a phenomenon associated with developed countries, where infertility treatments are commonplace. In fact, most infertile couples reside in developing/low-resource countries where infertility diagnosis and treatment is nonexistent, inaccessible or unaffordable by the vast majority of young men and women in need. The irony of this situation is that bilateral tubal occlusions, for which IVF was originally indicated and is the most effective treatment, is by far the most common cause of their infertility. We have addressed one aspect of this issue, the IVF laboratory, as part of a wider effort by the Walking Egg Project to design and establish small, dedicated centres in developing countries to provide assisted reproduction technologies that are affordable and accessible to a wider proportion of the population in need. The methods for conventional IVF designed to addresses tubal obstructions are relatively simple and free of complex instrumentation and the highly developed infrastructure common to high-resource centres. This simplified IVF system self-generates culture conditions in a closed system. After prolonged preclinical testing, a pilot clinical study was initiated in 2012 in Genk, Belgium. The findings suggest that a significant first step has been achieved in the effort to bring advanced assisted reproduction to developed countries using a low-resource but highly effective IVF system capable of bringing modern reproductive medicine to infertile couples in low-resource societies. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Analgesic use in pregnancy and male reproductive development
Hurtado-Gonzalez, Pablo; Mitchell, Rod T.
2017-01-01
Purpose of review Male reproductive disorders are common and increasing in incidence in many countries. Environmental factors (including pharmaceuticals) have been implicated in the development of these disorders. This review aims to summarise the emerging epidemiological and experimental evidence for a potential role of in-utero exposure to analgesics in the development of male reproductive disorders. Recent findings A number of epidemiological studies have demonstrated an association between in-utero exposure to analgesics and the development of cryptorchidism, although these findings are not consistent across all studies. Where present, these associations primarily relate to exposure during the second trimester of pregnancy. In-vivo and in-vitro experimental studies have demonstrated variable effects of exposure to analgesics on Leydig cell function in the fetal testis of rodents, particularly in terms of testosterone production. These effects frequently involve exposures that are in excess of those to which humans are exposed. Investigation of the effects of analgesics on human fetal testis have also demonstrated effects on Leydig cell function. Variation in species, model system, dosage and timing of exposure is likely to contribute to differences in the findings between studies. Summary There is increasing evidence for analgesic effects on the developing testis that have the potential to impair reproductive function. However, the importance of these findings in relation to human-relevant exposures and the risk of male reproductive disorders remains unclear. PMID:28277341
NASA Astrophysics Data System (ADS)
Philbrook, Nicola Anne
Manufactured nanoparticles (NPs) are a class of small (≤ 100 nm) materials that are being used for a variety of purposes, including industrial lubricants, food additives, antibacterial agents, as well as delivery systems for drug and gene therapies. Their unique characteristics due to their small size as well as their parent materials allow them to be exploited in convenience applications; however, some of these properties also allow them to interact with and invade biological systems. Few studies have been performed to determine the potential harm that NPs can inflict on reproductive and developmental processes in organisms. In this study, Drosophila melanogaster and CD-1 mice were orally exposed to varying doses of titanium dioxide (TiO 2) NPs, silver (Ag) NPs, or hydroxyl-functionalized carbon nanotubes (fCNTs) and Drosophila were also exposed to microparticles (MPs) as a control for particle size. The subsequent effect of these materials on reproduction and development were evaluated. Strikingly, each type of NP studied negatively affected either reproduction or development in one or both of the two model systems. TiO2 NPs significantly negative effected both CD-1 mouse development (100 mg/kg or 1000 mg/kg) as well as Drosophila female fecundity (0.005%-0.5% w/v). Ag NPs significantly reduced mouse fetus viability after prenatal exposure to10 mg/kg. Ag NPs also significantly decreased the developmental success of Drosophila when they were directly exposed to these NPs (0.05% - 0.5% w/v) compared to both the vehicle and MP controls. fCNTs significantly increased the presence of morphological defects, resorptions and skeletal abnormalities in CD-1 mice, but had little effect on Drosophila. We speculate that the differences seen in the effects of NP types may be partially due to differences in reproductive physiology as well as each organism's ability to internalize these NPs. Whereas the differing response of each organism to a NP type was likely due in part to varying durations of exposure. Since NPs are a popular commodity in today's consumer world, the research presented here accentuates the need for further studies on the detrimental effects that these particles may have on a variety of developing organisms and on female reproductive health.
21 CFR 884.6200 - Assisted reproduction laser system.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Assisted reproduction laser system. 884.6200... Assisted reproduction laser system. (a) Identification. The assisted reproduction laser system is a device that images, targets, and controls the power and pulse duration of a laser beam used to ablate a small...
21 CFR 884.6200 - Assisted reproduction laser system.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Assisted reproduction laser system. 884.6200... Assisted reproduction laser system. (a) Identification. The assisted reproduction laser system is a device that images, targets, and controls the power and pulse duration of a laser beam used to ablate a small...
21 CFR 884.6200 - Assisted reproduction laser system.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Assisted reproduction laser system. 884.6200... Assisted reproduction laser system. (a) Identification. The assisted reproduction laser system is a device that images, targets, and controls the power and pulse duration of a laser beam used to ablate a small...
21 CFR 884.6200 - Assisted reproduction laser system.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Assisted reproduction laser system. 884.6200... Assisted reproduction laser system. (a) Identification. The assisted reproduction laser system is a device that images, targets, and controls the power and pulse duration of a laser beam used to ablate a small...
21 CFR 884.6200 - Assisted reproduction laser system.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Assisted reproduction laser system. 884.6200... Assisted reproduction laser system. (a) Identification. The assisted reproduction laser system is a device that images, targets, and controls the power and pulse duration of a laser beam used to ablate a small...
ERIC Educational Resources Information Center
Hadjichambis, Andreas Ch.; Georgiou, Yiannis; Paraskeva-Hadjichambi, Demetra; Kyza, Eleni A.; Mappouras, Demetrios
2016-01-01
Despite the importance of understanding how the human reproductive system works, adolescents worldwide exhibit weak conceptual understanding, which leads to serious risks, such as unwanted pregnancies and sexually transmitted diseases. Studies focusing on the development and evaluation of inquiry-based learning interventions, promoting the…
ERIC Educational Resources Information Center
Sattler, Barbara
2005-01-01
Each of the elements required to create a healthy baby--genetics, the anatomy of the male and female reproductive system, the processes by which eggs and sperm are produced, the processes by which the embryo is created and implanted, maternal health during pregnancy, and embryonic/fetal growth and development--is vulnerable to damage by…
Early-life nutritional effects on the female reproductive system.
Chan, K A; Tsoulis, M W; Sloboda, D M
2015-02-01
There is now considerable epidemiological and experimental evidence indicating that early-life environmental conditions, including nutrition, affect subsequent development in later life. These conditions induce highly integrated responses in endocrine-related homeostasis, resulting in persistent changes in the developmental trajectory producing an altered adult phenotype. Early-life events trigger processes that prepare the individual for particular circumstances that are anticipated in the postnatal environment. However, where the intrauterine and postnatal environments differ markedly, such modifications to the developmental trajectory may prove maladaptive in later life. Reproductive maturation and function are similarly influenced by early-life events. This should not be surprising, because the primordial follicle pool is established early in life and is thus vulnerable to early-life events. Results of clinical and experimental studies have indicated that early-life adversity is associated with a decline in ovarian follicular reserve, changes in ovulation rates, and altered age at onset of puberty. However, the underlying mechanisms regulating the relationship between the early-life developmental environment and postnatal reproductive development and function are unclear. This review examines the evidence linking early-life nutrition and effects on the female reproductive system, bringing together clinical observations in humans and experimental data from targeted animal models. © 2015 Society for Endocrinology.
Developmental Programming and Endocrine Disruptor Effects on Reproductive Neuroendocrine Systems
Gore, Andrea C.
2009-01-01
The ability of a species to reproduce successfully requires the careful orchestration of developmental processes during critical time points, particularly the late embryonic and early postnatal periods. This article begins with a brief presentation of the evidence for how gonadal steroid hormones exert these imprinting effects upon the morphology of sexually differentiated hypothalamic brain regions, the mechanisms underlying these effects, and their implications in adulthood. Then, I review the evidence that aberrant exposure to hormonally-active substances such as exogenous endocrine-disrupting chemicals (EDCs), may result in improper hypothalamic programming, thereby decreasing reproductive success in adulthood. The field of endocrine disruption has shed new light on the discipline of basic reproductive neuroendocrinology through studies on how early life exposures to EDCs may alter gene expression via non-genomic, epigenetic mechanisms, including DNA methylation and histone acetylation. Importantly, these effects may be transmitted to future generations if the germline is affected via transgenerational, epigenetic actions. By understanding the mechanisms by which natural hormones and xenobiotics affect reproductive neuroendocrine systems, we will gain a better understanding of normal developmental processes, as well as to develop the potential ability to intervene when development is disrupted. PMID:18394690
Reproductive research on farm animals for Australia--some long-distance goals.
Martin, G B
1995-01-01
In Australia, much of the research on the reproduction of farm animals has emphasised the technological manipulation of the reproductive tract, gametes and embryos. However, most of the animal production in Australia is still based on sheep and beef cattle enterprises that are managed on an extensive scale; the managers need technologies that can be easily and cheaply implemented on a large scale, and that are aimed at extensive control rather than intensive manipulation. For example, for synchronizing oestrus in the wool flocks the "ram effect' has, and probably always will have, far more impact on extensive grazing systems than technologies based on exogenous prostaglandins or progestagens. This can also apply to the newer animal industries (such as emu farming), to human problems (such as population control), and to environmental problems (such as control of feral animals). Moreover, under the pressure of public opinion, the industries that are currently intensive are going 'free range'. In addition, surgical managerial tools (such as castration) will probably have to be abandoned or replaced. To cope with such profound influences, new types of reproductive management systems will be needed. This paper is an attempt to broaden our research horizons by developing the concept of 'control systems technologies', aimed at controlling reproductive performance rather than simply improving it. Ideas for such technologies already exist and are evident in the responses to environmental factors that our farm animals developed under the pressure of natural selection (before domestication). Stress, nutrition, photoperiod, lactation, and socio-sexual cues (e.g. pheromones) can all exert profound effects on reproductive activity. We already have a good grasp of the final common pathway through which the brain responses to these factors affect gonadal activity, namely the hypothalamic system that generates pulses of gonadotrophin-releasing hormone. All we need to do is learn how the major environmental cues exert their impact on the systems that control the final common pathway. When we understand them, we shall be able to manipulate them. This is not too speculative; we already have several technologies that take advantage of this approach, including steroid-based contraceptives, the "ram effect', a vaccine-based antifertility treatment for rangeland cattle and the melatonin formulation used to control seasonal breeding in sheep. These and the other pathways linking environmental inputs to reproductive output are waiting to be explored, explained and exploited.
Environmental endocrine disruptors: Effects on the human male reproductive system.
Sweeney, M F; Hasan, N; Soto, A M; Sonnenschein, C
2015-12-01
Incidences of altered development and neoplasia of male reproductive organs have increased during the last 50 years, as shown by epidemiological data. These data are associated with the increased presence of environmental chemicals, specifically "endocrine disruptors," that interfere with normal hormonal action. Much research has gone into testing the effects of specific endocrine disrupting chemicals (EDCs) on the development of male reproductive organs and endocrine-related cancers in both in vitro and in vivo models. Efforts have been made to bridge the accruing laboratory findings with the epidemiological data to draw conclusions regarding the relationship between EDCs, altered development and carcinogenesis. The ability of EDCs to predispose target fetal and adult tissues to neoplastic transformation is best explained under the framework of the tissue organization field theory of carcinogenesis (TOFT), which posits that carcinogenesis is development gone awry. Here, we focus on the available evidence, from both empirical and epidemiological studies, regarding the effects of EDCs on male reproductive development and carcinogenesis of endocrine target tissues. We also critique current research methodology utilized in the investigation of EDCs effects and outline what could possibly be done to address these obstacles moving forward.
Male pregnancy in seahorses and pipefish: beyond the mammalian model.
Stölting, Kai N; Wilson, Anthony B
2007-09-01
Pregnancy has been traditionally defined as the period during which developing embryos are incubated in the body after egg-sperm union. Despite strong similarities between viviparity in mammals and other vertebrate groups, researchers have historically been reluctant to use the term pregnancy for non-mammals in recognition of the highly developed form of viviparity in eutherians. Syngnathid fishes (seahorses and pipefishes) have a unique reproductive system, where the male incubates developing embryos in a specialized brooding structure in which they are aerated, osmoregulated, protected and likely provisioned during their development. Recent insights into physiological, morphological and genetic changes associated with syngnathid reproduction provide compelling evidence that male incubation in these species is a highly specialized form of reproduction akin to other forms of viviparity. Here, we review these recent advances, highlighting similarities and differences between seahorse and mammalian pregnancy. Understanding the changes associated with the parallel evolution of male pregnancy in the two major syngnathid lineages will help to identify key innovations that facilitated the development of this unique form of reproduction and, through comparison with other forms of live bearing, may allow the identification of a common set of characteristics shared by all viviparous organisms.
ERIC Educational Resources Information Center
Manpower Administration (DOL), Washington, DC. Job Corps.
This self-study program for the high-school level contains lessons in the following subjects: Plants and Photosynthesis; The Human Digestive System; Functions of the Blood; Human Circulation and Respiration; Reproduction of a Single Cell; Reproduction by Male and Female Cells; The Human Reproductive System; Genetics and Heredity; The Nervous…
Reproductive toxicity: Male and female reproductive systems as targets for chemical injury
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mattison, D.R.; Plowchalk, D.R.; Meadows, M.J.
On the basis of current knowledge of reproductive biology and toxicology, it is apparent that chemicals affecting reproduction may elicit their effects at a number of sites in both the male and the female reproductive system. This multiplicity of targets is attributable to the dynamic nature of the reproductive system, in which the hypothalamic-pituitary-gonadal axis is controlled by precise positive and negative feedback mechanisms among its components. Interference by a xenobiotic at any level in either the male or the female reproductive system may ultimately impair hypothalamic or pituitary function. Normal gonadal processes such as spermatogenesis or oogenesis, ejaculation ormore » ovulation, hormone production by Leydig or granulosa cells, and the structure or function of the accessory reproductive structures (e.g., epididymis, fallopian tube) also appear vulnerable to xenobiotics. The reproductive system is a complex one that requires local and circulating hormones for control. This brief review illustrates a system for characterizing the mechanism of action of reproductive toxicants, as well as for defining the sites available for disruption of reproduction. Unfortunately, at present, data addressing the actual vulnerability of reproduction are sorely lacking. However, when experiments have been conducted and combined with epidemiologic data or clinical observation, it has been possible to demonstrate impairment of reproductive processes by xenobiotics. The role of environmental exposure to xenobiotics in the increase in infertility that has been observed remains to be defined. 87 references.« less
Rouhana, Labib; Tasaki, Junichi; Saberi, Amir; Newmark, Phillip A.
2017-01-01
Cytoplasmic polyadenylation is a mechanism of mRNA regulation prevalent in metazoan germ cells; it is largely dependent on Cytoplasmic Polyadenylation Element Binding proteins (CPEBs). Two CPEB homologs were identified in the planarian Schmidtea mediterranea. Smed-CPEB1 is expressed in ovaries and yolk glands of sexually mature planarians, and required for oocyte and yolk gland development. In contrast, Smed-CPEB2 is expressed in the testes and the central nervous system; its function is required for spermatogenesis as well as non-autonomously for development of ovaries and accessory reproductive organs. Transcriptome analysis of CPEB knockdown animals uncovered a comprehensive collection of molecular markers for reproductive structures in S. mediterranea, including ovaries, testes, yolk glands, and the copulatory apparatus. Analysis by RNA interference revealed contributions for a dozen of these genes during oogenesis, spermatogenesis, or capsule formation. We also present evidence suggesting that Smed-CPEB2 promotes translation of Neuropeptide Y-8, a prohormone required for planarian sexual maturation. These findings provide mechanistic insight into potentially conserved processes of germ cell development, as well as events involved in capsule deposition by flatworms. PMID:28434803
Antidiabetic therapies and male reproductive function: where do we stand?
Tavares, R S; Escada-Rebelo, S; Silva, A F; Sousa, M I; Ramalho-Santos, J; Amaral, S
2018-01-01
Diabetes mellitus has been increasing at alarming rates in recent years, thus jeopardizing human health worldwide. Several antidiabetic drugs have been introduced in the market to manage glycemic levels, and proven effective in avoiding, minimizing or preventing the appearance or development of diabetes mellitus-related complications. However, and despite the established association between such pathology and male reproductive dysfunction, the influence of these therapeutic interventions on such topics have been scarcely explored. Importantly, this pathology may contribute toward the global decline in male fertility, giving the increasing preponderance of diabetes mellitus in young men at their reproductive age. Therefore, it is mandatory that the reproductive health of diabetic individuals is maintained during the antidiabetic treatment. With this in mind, we have gathered the available information and made a critical analysis regarding the effects of several antidiabetic drugs on male reproductive function. Unlike insulin, which has a clear and fundamental role on male reproductive function, the other antidiabetic therapies' effects at this level seem incoherent. In fact, studies are highly controversial possibly due to the different experimental study approaches, which, in our opinion, suggests caution when it comes to prescribing such drugs to young diabetic patients. Overall, much is still to be determined and further studies are needed to clarify the safety of these antidiabetic strategies on male reproductive system. Aspects such as the effects of insulin levels variations, consequent of insulin therapy, as well as what will be the impact of the side effect hypoglycemia, common to several therapeutic strategies discussed, on the male reproductive system are still to be addressed. © 2018 Society for Reproduction and Fertility.
Okamura, Hiroaki; Yamamura, Takashi; Wakabayashi, Yoshihiro
2013-05-01
The hypothalamo-pituitary-gonadal (HPG) axis is the regulatory system for reproduction in mammals. Because secretion of gonadotropin-releasing hormone (GnRH) into the portal vessels is the final step at which the brain controls gonadal activities, the GnRH neuronal system had been thought to be central to the HPG axis. A newly discovered neural peptide, kisspeptin, has opened a new era in reproductive neuroendocrinology. As shown in a variety of mammals, kisspeptin is a potent endogenous secretagogue of GnRH, and the kisspeptin neuronal system governs both the pulsatile GnRH secretion that drives folliculogenesis, spermatogenesis and steroidogenesis, and the GnRH surge that triggers ovulation in females. The kisspeptin neuronal system is therefore considered a master player in the central control of mammalian reproduction, and kisspeptin and related substances could therefore be valuable for the development of novel strategies for the management of fertility in farm animals. To this end, the present review aimed to summarize the current research on kisspeptin signaling with a focus on domestic animals such as sheep, goats, cattle, pigs and horses. © 2013 Japanese Society of Animal Science.
Sense and Nonsense in Metabolic Control of Reproduction
Schneider, Jill E.; Klingerman, Candice M.; Abdulhay, Amir
2012-01-01
An exciting synergistic interaction occurs among researchers working at the interface of reproductive biology and energy homeostasis. Reproductive biologists benefit from the theories, experimental designs, and methodologies used by experts on energy homeostasis while they bring context and meaning to the study of energy homeostasis. There is a growing recognition that identification of candidate genes for obesity is little more than meaningless reductionism unless those genes and their expression are placed in a developmental, environmental, and evolutionary context. Reproductive biology provides this context because metabolic energy is the most important factor that controls reproductive success and gonadal hormones affect energy intake, storage, and expenditure. Reproductive hormone secretion changes during development, and reproductive success is key to evolutionary adaptation, the process that most likely molded the mechanisms that control energy balance. It is likely that by viewing energy intake, storage, and expenditure in the context of reproductive success, we will gain insight into human obesity, eating disorders, diabetes, and other pathologies related to fuel homeostasis. This review emphasizes the metabolic hypothesis: a sensory system monitors the availability of oxidizable metabolic fuels and orchestrates behavioral motivation to optimize reproductive success in environments where energy availability fluctuates or is unpredictable. PMID:22649413
Sense and nonsense in metabolic control of reproduction.
Schneider, Jill E; Klingerman, Candice M; Abdulhay, Amir
2012-01-01
An exciting synergistic interaction occurs among researchers working at the interface of reproductive biology and energy homeostasis. Reproductive biologists benefit from the theories, experimental designs, and methodologies used by experts on energy homeostasis while they bring context and meaning to the study of energy homeostasis. There is a growing recognition that identification of candidate genes for obesity is little more than meaningless reductionism unless those genes and their expression are placed in a developmental, environmental, and evolutionary context. Reproductive biology provides this context because metabolic energy is the most important factor that controls reproductive success and gonadal hormones affect energy intake, storage, and expenditure. Reproductive hormone secretion changes during development, and reproductive success is key to evolutionary adaptation, the process that most likely molded the mechanisms that control energy balance. It is likely that by viewing energy intake, storage, and expenditure in the context of reproductive success, we will gain insight into human obesity, eating disorders, diabetes, and other pathologies related to fuel homeostasis. This review emphasizes the metabolic hypothesis: a sensory system monitors the availability of oxidizable metabolic fuels and orchestrates behavioral motivation to optimize reproductive success in environments where energy availability fluctuates or is unpredictable.
Environmental factors, epigenetics, and developmental origin of reproductive disorders.
Ho, Shuk-Mei; Cheong, Ana; Adgent, Margaret A; Veevers, Jennifer; Suen, Alisa A; Tam, Neville N C; Leung, Yuet-Kin; Jefferson, Wendy N; Williams, Carmen J
2017-03-01
Sex-specific differentiation, development, and function of the reproductive system are largely dependent on steroid hormones. For this reason, developmental exposure to estrogenic and anti-androgenic endocrine disrupting chemicals (EDCs) is associated with reproductive dysfunction in adulthood. Human data in support of "Developmental Origins of Health and Disease" (DOHaD) comes from multigenerational studies on offspring of diethylstilbestrol-exposed mothers/grandmothers. Animal data indicate that ovarian reserve, female cycling, adult uterine abnormalities, sperm quality, prostate disease, and mating behavior are susceptible to DOHaD effects induced by EDCs such as bisphenol A, genistein, diethylstilbestrol, p,p'-dichlorodiphenyl-dichloroethylene, phthalates, and polyaromatic hydrocarbons. Mechanisms underlying these EDC effects include direct mimicry of sex steroids or morphogens and interference with epigenomic sculpting during cell and tissue differentiation. Exposure to EDCs is associated with abnormal DNA methylation and other epigenetic modifications, as well as altered expression of genes important for development and function of reproductive tissues. Here we review the literature exploring the connections between developmental exposure to EDCs and adult reproductive dysfunction, and the mechanisms underlying these effects. Copyright © 2016 Elsevier Inc. All rights reserved.
DOH to integrate reproductive health in health care delivery.
According to a Department of Health (DOH) official speaking at the recent Reproductive Health Advocacy Forum in Zamboanga City, the concept of reproductive health (RH) is now on the way to being fully integrated into the Philippines' primary health care system. The DOH is also developing integrated information, education, and communication material for an intensified advocacy campaign on RH among target groups in communities. The forum was held to enhance the knowledge and practice of RH among health, population and development program managers, field workers, and local government units. In this new RH framework, family planning becomes just one of many concerns of the RH package of services which includes maternal and child health, sexuality education, the prevention and treatment of abortion complications, prevention of violence against women, and the treatment of reproductive tract infections. Of concern, however, the Asian economic crisis has led the Philippine government to reduce funding, jeopardizing the public sector delivery of basic services, including reproductive health care. The crisis has also forced other governments in the region to reassess their priorities and redirect their available resources into projects which are practical and sustainable.
Macejova, Dana; Toporova, L; Brtko, J
2016-07-01
Retinoic acid (RA), an active form of vitamin A, regulates the embryonic development, male and female reproduction and induces important effects on the cell development, proliferation, and differentiation. These effects are mediated by the retinoid (RAR) and rexinoid nuclear receptors (RXR), which are considered to be a ligand-activated, DNA-binding, trans-acting, and transcription-modulating proteins, involved in a general molecular mechanism responsible for the transcriptional responses in target genes. Organotin compounds are typical environmental contaminants and suspected endocrine disrupting substances. They may affect processes of reproductive system in mammals, predominantly via nuclear receptor signaling pathways. Triorganotins, such as tributyltin chloride (TBTCl) and triphenyltin chloride (TPTCl), are capable to bind to RXR molecules, and thus represent potent agonists of RXR subtypes of nuclear receptors not sharing any structural characteristics with endogenous ligands of nuclear receptors. Th is article summarizes selected effects of biologically active retinoids and rexinoids on both male and female reproduction and also deals with the effects of organotin compounds evoking endocrine disrupting actions in reproduction.
Environmental Factors, Epigenetics, and Developmental Origin of Reproductive Disorders
Ho, Shuk-Mei; Cheong, Ana; Adgent, Margaret A.; Veevers, Jennifer; Suen, Alisa A.; Tam, Neville N.C.; Leung, Yuet-Kin; Jefferson, Wendy N.; Williams, Carmen J.
2016-01-01
Sex-specific differentiation, development, and function of the reproductive system are largely dependent on steroid hormones. For this reason, developmental exposure to estrogenic and anti-androgenic endocrine disrupting chemicals (EDCs) is associated with reproductive dysfunction in adulthood. Human data in support of “Developmental Origins of Health and Disease” (DOHaD) comes from multigenerational studies on offspring of diethylstilbestrol-exposed mothers/grandmothers. Animal data indicate that ovarian reserve, female cycling, adult uterine abnormalities, sperm quality, prostate disease, and mating behavior are susceptible to DOHaD effects induced by EDCs such as bisphenol A, genistein, diethylstilbestrol, p,p′-dichlorodiphenyl-dichloroethylene, phthalates, and polyaromatic hydrocarbons. Mechanisms underlying these EDC effects include direct mimicry of sex steroids or morphogens and interference with epigenomic sculpting during cell and tissue differentiation. Exposure to EDCs is associated with abnormal DNA methylation and other epigenetic modifications, as well as altered expression of genes important for development and function of reproductive tissues. Here we review the literature exploring the connections between developmental exposure to EDCs and adult reproductive dysfunction, and the mechanisms underlying these effects. PMID:27421580
Witorsch, Raphael J
2016-01-01
This article reviews the influence of the hypothalamo-pituitary-adrenocortical (HPA) axis on mammalian male and female reproduction and development of offspring and its potential impact on the identification of endocrine disruptive chemicals by in vivo assays. In the adult male rat and baboon, stress suppresses testosterone secretion via a direct inhibitory effect of elevated glucocorticoids on Leydig cells. In adult female sheep, stress disrupts reproductive function via multi-stage mechanisms involving glucocorticoid-mediated suppression of LH secretion, LH action on the ovary and the action of estradiol on its target cells (e.g., uterus). While physiological concentrations of endogenous glucocorticoids are supportive of fetal development, excessive glucocorticoids in utero (i.e., maternal stress) adversely affect mammalian offspring by "programing" abnormalities that are primarily manifest postpartum. The influence of stress on reproduction and development can also be mediated by 11β-hydroxysteroid dehydrogenase (HSD), a bi-directional oxidative:reductive pathway, which governs the balance between biologically active (reduced) endogenous glucocorticoid and inactive (oxidized) metabolites. This pathway is mediated primarily by two isozymes, 11β - HSD1 (reductase) and 11β-HSD2 (oxidase) which act both in an intracrine (intracellular) and endocrine (systemic) fashion. The 11β-HSD pathway appears to play a variety of physiological roles in mammalian reproduction and development and is a target for selected xenobiotics. The effects of the HPA axis on mammalian reproduction and development are potential confounders for in vivo bioassays in rodents employed to identify endocrine disruptive chemicals. Accordingly, consideration of the impact of the HPA axis should be incorporated into the design of bioassays for evaluating endocrine disruptors.
Prokineticins in central and peripheral control of human reproduction.
Traboulsi, Wael; Brouillet, Sophie; Sergent, Frederic; Boufettal, Houssine; Samouh, Naima; Aboussaouira, Touria; Hoffmann, Pascale; Feige, Jean Jacques; Benharouga, Mohamed; Alfaidy, Nadia
2015-11-01
Prokineticin 1 (PROK1) and (PROK2), are two closely related proteins that were identified as the mammalian homologs of their two amphibian homologs, mamba intestinal toxin (MIT-1) and Bv8. PROKs activate two G-protein linked receptors (prokineticin receptor 1 and 2, PROKR1 and PROKR2). Both PROK1 and PROK2 have been found to regulate a stunning array of biological functions. In particular, PROKs stimulate gastrointestinal motility, thus accounting for their family name "prokineticins". PROK1 acts as a potent angiogenic mitogen, thus earning its other name, endocrine gland-derived vascular endothelial factor. In contrast, PROK2 signaling pathway has been shown to be a critical regulator of olfactory bulb morphogenesis and sexual maturation. During the last decade, strong evidences established the key roles of prokineticins in the control of human central and peripheral reproductive processes. PROKs act as main regulators of the physiological functions of the ovary, uterus, placenta, and testis, with marked dysfunctions in various pathological conditions such as recurrent pregnancy loss, and preeclampsia. PROKs have also been associated to the tumor development of some of these organs. In the central system, prokineticins control the migration of GnRH neurons, a key process that controls reproductive functions. Importantly, mutations in PROK2 and PROKR2 are associated to the development of Kallmann syndrome, with direct consequences on the reproductive system. This review describes the finely tuned actions of prokineticins in the control of the central and peripheral reproductive processes. Also, it discusses future research directions for the use of these cytokines as diagnostic markers for several reproductive diseases.
Impact of the environment on reproductive health.
1991-01-01
The WHO workshop on the impact of the environment on reproductive health is summarized. Topics include the nature of environmental factors affecting reproductive health, environmental factors blamed for declining sperm quantity and quality, the effects of natural and man-made disasters on reproductive health, chemical pollutants, how the environment damages reproductive health, and research needs for better research methodologies and surveillance data. Recommendations are made to: 1) promote international research collaboration with an emphasis on consistency of methodological approaches for assessing developmental and reproductive toxicity, on development of improved surveillance systems and data bases, an strengthening international disaster alert and evaluation systems; 2) promote research capabilities for multidisciplinary studies, for interactive studies of the environment and cellular processes, and for expansion of training and education; and 3) take action on priority problems of exposure to chemical, physical, and biological agents, of exposure to pesticides among specific populations, and of inadequate screening methods for identification of environmental chemicals. The costs of environmental injury to reproduction include subfertility, intrauterine growth retardation, spontaneous abortion, and various birth defects. Developed country's primary threats are from chemical pollution, radiation, and stress. There is a large gap in knowledge. Caution is urged in understanding the direct relationship between environmental causes and infertility. Sexual health is difficult to assess and research is suggested. Exposure to excessive vitamin A and toxic chemicals are cited as agents probably having serious effects on malformations. Sperm quality has declined over the decades; there is speculation about the potential causes. The effects of radiation such as at Chernobyl are described. Toxic chemical exposure such as in Bhopal, India killed thousands. Neurological damage is reported for fetuses and infants exposed to methyl mercury. There is the beginning of evidence that complications of pregnancy may be related to pollution levels surrounding industrial plants. Reproductive health is affected through chromosome damage and cell destruction, prenatal death, altered growth, fetal abnormalities, postnatal death, functional learning deficits, and premature aging.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tian, Hua; Li, Yun; Wang, Wei
Monocrotophos is a highly toxic organophosphorus pesticide that has been confirmed to be an endocrine‐disrupting chemical. To evaluate the influence of this pollutant on the reproductive system of male fish, we studied the sex steroid levels, reproductive traits, sex ratio, and reproductive success in male guppies (Poecilia reticulata) exposed to 40% monocrotophos pesticide at the nominal concentrations of 0.01, 0.10, and 1.00 mg/L for 90 days from birth to adulthood in a semi‐static exposure system. Radioimmunoassay and western blot analyses demonstrated that the long‐term exposure to monocrotophos pesticide during the sexual development of male guppies caused a significant increase inmore » 17β‐estradiol levels and consequently induced vitellogenin synthesis, suggesting the feminization of the males. Monocrotophos pesticide also caused a significant decrease in testosterone levels, which consequently inhibited testis growth and reduced the sperm count and the area and intensity of their sexually attractive orange spots, which collectively indicated the significant demasculinization of the male sexual characteristics. Furthermore, these changes in the sexual characteristics at the cellular and organ levels translated into ecologically important effects on the reproductive success at the individual level, as measured by a decrease in offspring production and survival rate. The present study provides the first evidence that monocrotophos pesticide can cause severe reproductive abnormalities in fish due to its endocrine‐disrupting action. -- Highlights: ► Monocrotophos pesticide caused an increase in 17β‐estradiol levels of male guppies. ► Monocrotophos pesticide induced vitellogenin synthesis of male guppies. ► Monocrotophos pesticide caused a decrease in testosterone levels of male guppies. ► Monocrotophos pesticide caused demasculinization of male sexual characteristics. ► Monocrotophos pesticide caused a reduction in reproductive success of male guppies.« less
Malignant Tumors of the Female Reproductive System
Labrèche, France
2012-01-01
This review summarizes the epidemiology of cancer of the female reproductive system and associated lifestyle factors. It also assesses the available evidence for occupational factors associated with these cancers. Cervical, endometrial, and ovarian cancers are relatively common, and cause significant cancer morbidity and mortality worldwide, whereas vulvar, vaginal, fallopian tube cancers, and choriocarcinomas are very rare. As several lifestyle factors are known to play a major role in the etiology of these cancers, very few published studies have investigated possible relationships with occupational factors. Some occupational exposures have been associated with increased risks of these cancers, but apart from the available evidence on the relationships between asbestos fibers and ovarian cancer, and tetrachloroethylene and cervical cancer, the data is rather scarce. Given the multifactorial nature of cancers of the female reproductive system, it is of the utmost importance to conduct occupational studies that will gather detailed data on potential individual confounding factors, in particular reproductive history and other factors that influence the body's hormonal environment, together with information on socio-economic status and lifestyle factors, including physical activity from multiple sources. Studies on the mechanisms of carcinogenesis in the female reproductive organs are also needed in order to elucidate the possible role of chemical exposures in the development of these cancers. PMID:23019529
Systems Toxicology of Male Reproductive Development ...
Adverse trends in male reproductive health have been reported for increased rates of testicular germ cell tumor, low semen quality, cryptorchidism, and hypospadias. An association with prenatal environmental exposure has been inferred from human and animal studies underlying male reproductive developmental defects. The present study established the links between environmental chemicals, molecular targets, and adverse outcomes using U.S. EPA animal study (ToxRefDB) and high-throughput screening (ToxCast) databases. This systems-based approach revealed a phenotypic hierarchy across 63 chemicals and a pleiotropic in vitro bioactivity profile. Although estrogenic and anti-androgenic activities have been extensively studied in male reproductive developmental toxicity, the present study showed these receptor targets to be only a subset of the potential landscape of molecular targets. A variety of chemical (e.g. phthalates, conazoles, carbamates, and phenol compounds) and bioactivity (e.g. nuclear receptors, vascular remodeling proteins, and cytochrome-P450 reductases) clusters further suggested multiple pathways leading to the adverse outcomes. This points to the need for multi-scale systems models to predict whether the occurrence of one adverse outcome may predict the risk of another. Imbalances in androgen and estrogen signaling have been a general focus in male reproductive toxicology research. While a number of recent studies have demonstrated that both hormonal
Kisspeptin modulates sexual and emotional brain processing in humans.
Comninos, Alexander N; Wall, Matthew B; Demetriou, Lysia; Shah, Amar J; Clarke, Sophie A; Narayanaswamy, Shakunthala; Nesbitt, Alexander; Izzi-Engbeaya, Chioma; Prague, Julia K; Abbara, Ali; Ratnasabapathy, Risheka; Salem, Victoria; Nijher, Gurjinder M; Jayasena, Channa N; Tanner, Mark; Bassett, Paul; Mehta, Amrish; Rabiner, Eugenii A; Hönigsperger, Christoph; Silva, Meire Ribeiro; Brandtzaeg, Ole Kristian; Lundanes, Elsa; Wilson, Steven Ray; Brown, Rachel C; Thomas, Sarah A; Bloom, Stephen R; Dhillo, Waljit S
2017-02-01
Sex, emotion, and reproduction are fundamental and tightly entwined aspects of human behavior. At a population level in humans, both the desire for sexual stimulation and the desire to bond with a partner are important precursors to reproduction. However, the relationships between these processes are incompletely understood. The limbic brain system has key roles in sexual and emotional behaviors, and is a likely candidate system for the integration of behavior with the hormonal reproductive axis. We investigated the effects of kisspeptin, a recently identified key reproductive hormone, on limbic brain activity and behavior. Using a combination of functional neuroimaging and hormonal and psychometric analyses, we compared the effects of kisspeptin versus vehicle administration in 29 healthy heterosexual young men. We demonstrated that kisspeptin administration enhanced limbic brain activity specifically in response to sexual and couple-bonding stimuli. Furthermore, kisspeptin's enhancement of limbic brain structures correlated with psychometric measures of reward, drive, mood, and sexual aversion, providing functional significance. In addition, kisspeptin administration attenuated negative mood. Collectively, our data provide evidence of an undescribed role for kisspeptin in integrating sexual and emotional brain processing with reproduction in humans. These results have important implications for our understanding of reproductive biology and are highly relevant to the current pharmacological development of kisspeptin as a potential therapeutic agent for patients with common disorders of reproductive function. National Institute for Health Research (NIHR), Wellcome Trust (Ref 080268), and the Medical Research Council (MRC).
Prenatal programming of neuroendocrine reproductive function.
Evans, Neil P; Bellingham, Michelle; Robinson, Jane E
2016-07-01
It is now well recognized that the gestational environment can have long-lasting effects not only on the life span and health span of an individual but also, through potential epigenetic changes, on future generations. This article reviews the "prenatal programming" of the neuroendocrine systems that regulate reproduction, with a specific focus on the lessons learned using ovine models. The review examines the critical roles played by steroids in normal reproductive development before considering the effects of prenatal exposure to exogenous steroid hormones including androgens and estrogens, the effects of maternal nutrition and stress during gestation, and the effects of exogenous chemicals such as alcohol and environment chemicals. In so doing, it becomes evident that, to maximize fitness, the regulation of reproduction has evolved to be responsive to many different internal and external cues and that the GnRH neurosecretory system expresses a degree of plasticity throughout life. During fetal life, however, the system is particularly sensitive to change and at this time, the GnRH neurosecretory system can be "shaped" both to achieve normal sexually differentiated function but also in ways that may adversely affect or even prevent "normal function". The exact mechanisms through which these programmed changes are brought about remain largely uncharacterized but are likely to differ depending on the factor, the timing of exposure to that factor, and the species. It would appear, however, that some afferent systems to the GnRH neurons such as kisspeptin, may be critical in this regard as it would appear to be sensitive to a wide variety of factors that can program reproductive function. Finally, it has been noted that the prenatal programming of neuroendocrine reproductive function can be associated with epigenetic changes, which would suggest that in addition to direct effects on the exposed offspring, prenatal programming could have transgenerational effects on reproductive potential. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Management considerations in heifer development and puberty.
Patterson, D J; Perry, R C; Kiracofe, G H; Bellows, R A; Staigmiller, R B; Corah, L R
1992-12-01
Management of replacement beef heifers should focus on factors that enhance physiological processes that promote puberty. Age at puberty is important as a production trait when heifers are bred to calve as 2-yr-olds and in systems that impose restricted breeding periods. Calving by 24 mo of age is necessary to obtain maximum lifetime productivity. Because the reproductive system is the last major organ system to mature, factors that influence puberty are critical. The influence of environment on the sequence of events leading to puberty in the heifer is dictated largely by the nutritional status of the animal and related effects on growth rate and development. Management strategies have been designed to ensure that heifers reach a prebreeding target weight that supports optimum reproductive performance, and consequences of inadequate or excessive development have been evaluated. Those strategies are based on evidence linking postweaning nutritional development with key reproductive events that include age at puberty and first breeding, conception, pregnancy loss, incidence and severity of dystocia, and postpartum interval to estrus. Management alternatives that ultimately affect lifetime productivity and reproductive performance of heifers begin at birth and include decisions that involve growth-promoting implants, creep-feeding, breed type and(or) species, birth date and weaning weight, social interaction, sire selection, and exogenous hormonal treatments to synchronize or induce estrus. Basic and applied future research efforts should converge to match in a realistic manner the production potential of the animal with available resources. Strategies that incorporate consideration of nutrition, genetics, and emerging management techniques will need to be tested to enable producers to make decisions that result in profit. This review evaluates the current status of knowledge relating to management of the replacement beef heifer and serves to stimulate research needed to enhance management techniques to ensure puberty at an optimal age.
21 CFR 884.6170 - Assisted reproduction water and water purification systems.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high quality...
21 CFR 884.6170 - Assisted reproduction water and water purification systems.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high quality...
21 CFR 884.6170 - Assisted reproduction water and water purification systems.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high quality...
21 CFR 884.6170 - Assisted reproduction water and water purification systems.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high quality...
21 CFR 884.6170 - Assisted reproduction water and water purification systems.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Assisted reproduction water and water purification... Devices § 884.6170 Assisted reproduction water and water purification systems. (a) Identification. Assisted reproduction water purification systems are devices specifically intended to generate high quality...
[Impact on environmental factors on the reproductive system and fetal development].
Dulskiene, Virginija; Maroziene, Ligita
2002-01-01
A literature review discusses the effect of selected environmental factors on women reproductive system, fetal development and growth. According to recent reports, 2-3% of newborns have congenital malformations. These malformations are caused by interaction of genetic and environmental factors. Exposure of paternal or maternal organisms to environmental hazards may damage germ cells or interfere fetal development, resulting in malformation of various organ systems. Since environmental hazards exposures are complex, it is difficult to establish the primary effect of single factor. Factors, that are known to increase the risk of congenital malformations, preterm delivery or spontaneous abortion, are classified into five groups--psychological, social, biological, physical and chemical factors. The governments of most counties recognize the effect of hazardous environmental factors on public health as global problem. World Health Organization encourages researches, aimed at evaluation of various environmental factors impact on health of pregnant women and their offsprings.
Gao, Shanshan; Xiong, Wenfeng; Wei, Luting; Liu, Juanjuan; Liu, Xing; Xie, Jia; Song, Xiaowen; Bi, Jingxiu; Li, Bin
2018-06-01
Latrophilin of Tribolium castaneum (Tclph) has been reported to play crucial roles in growth, development and reproduction. However, the regulatory mechanism of Tclph associated with these physiology processes is unknown. Thus, the global transcriptome profiles between RNAi treated (ds-Tclph) and control larvae of T. castaneum were analyzed by RNA-sequencing. Totally, 274 differentially expressed genes (DEGs) were identified between the ds-Tclph and control samples. These DEGs were classified into 42 GO functional groups, including developmental process, reproduction and stress response. The results indicated that knockdown of Tclph disturbed the antioxidant activity process, and partially inhibited the serine protease (SP) and lipase signaling pathways to regulate the development and reproduction as well as the decreasing of the stress response in T. castaneum. Additionally, knockdown of Tclph suppressed IMD immunity pathways which likely modulated the effects of Tclph on stress response. Interestingly, CSPs, ESTs, CYPs, AOXs and BGs were significantly down-regulated in ds-Tclph larvae, implying that they cooperated with Tclph to reduce the activity of cellular metabolism system. FMOs was up-regulated in ds-Tclph insects suggested it may be involved in detoxifying alkaloid of insect metabolism system. These results implied that Tclph participated in phase 0, I and II cellular detoxification. Furthermore, RNAi against Tclph increased larval susceptibility to carbamates and organophosphates insecticides, supporting that Tclph was indeed involved into the insecticide susceptibility in T. castaneum.
Is Your Child at Risk for Lead Poisoning?
ERIC Educational Resources Information Center
Berg, Nancy
1992-01-01
Lead poisoning is the number one environmental threat to children. At low levels it harms development, damages blood cells, and lowers IQ. At higher levels, it damages the nervous system, kidneys, reproductive system, and mental development. The article examines risk factors and discusses contamination, testing for lead, and prevention. (SM)
A growth stage and heat unit model for Hedysarum Boreale
USDA-ARS?s Scientific Manuscript database
A system for staging sweetvetch (Hedysarum boreale Nutt. [Fabaceae]) through vegetative and reproductive plant development was developed that corresponds with a heat-unit or growing degree day (GDD) model. This system designates 14 finite stages, V1 through V6 (pre-flowering or vegetative), and R1 ...
At the crossroads of physiology and ecology: food supply and the timing of avian reproduction.
Davies, Scott; Deviche, Pierre
2014-06-01
This article is part of a Special Issue “Energy Balance”. The decision of when to breed is crucial to the reproductive success and fitness of seasonally breeding birds. The availability of food for adults prior to breeding has long been thought to play a critical role in timing the initiation of seasonal reproductive events, in particular laying. However, unequivocal evidence for such a role remains limited and the physiological mechanisms by which an increase in food availability results in seasonal activation of the reproductive system are largely speculative. This lack of mechanistic information partly reflects a lack of integration of ecological and physiological approaches to study seasonal reproduction. Indeed, most work pertaining to the role of food availability for adults on the timing of avian reproduction has been ecological and has focused almost exclusively on female traits associated with reproductive timing (e.g., lay date and clutch size). By contrast, most work on the physiological bases of the relationship between food availability and the timing of reproduction has investigated male traits associated with reproductive development (e.g., reproductive hormones and gonadal development). To advance our understanding of these topics, we review the role of proximate factors including food availability, social factors, and ambient temperature in the control of breeding decisions, and discuss the role of three potential candidates (leptin, glucocorticoids, and GnIH-neuropeptide Y) that may mediate the effects of food availability on these decisions. We emphasize that future progress in this area is heavily contingent upon the use of physiology-based approaches and their integration into current ecological frameworks. Published by Elsevier Inc.
Santiago-Moreno, Julian; Esteso, Milagros Cristina; Villaverde-Morcillo, Silvia; Toledano-Díaz, Adolfo; Castaño, Cristina; Velázquez, Rosario; López-Sebastián, Antonio; Goya, Agustín López; Martínez, Javier Gimeno
2016-01-01
Postcopulatory sexual selection through sperm competition may be an important evolutionary force affecting many reproductive traits, including sperm morphometrics. Environmental factors such as pollutants, pesticides, and climate change may affect different sperm traits, and thus reproduction, in sensitive bird species. Many sperm-handling processes used in assisted reproductive techniques may also affect the size of sperm cells. The accurately measured dimensions of sperm cell structures (especially the head) can thus be used as indicators of environmental influences, in improving our understanding of reproductive and evolutionary strategies, and for optimizing assisted reproductive techniques (e.g., sperm cryopreservation) for use with birds. Computer-assisted sperm morphometry analysis (CASA-Morph) provides an accurate and reliable method for assessing sperm morphometry, reducing the problem of subjectivity associated with human visual assessment. Computerized systems have been standardized for use with semen from different mammalian species. Avian spermatozoa, however, are filiform, limiting their analysis with such systems, which were developed to examine the approximately spherical heads of mammalian sperm cells. To help overcome this, the standardization of staining techniques to be used in computer-assessed light microscopical methods is a priority. The present review discusses these points and describes the sperm morphometric characteristics of several wild and domestic bird species. PMID:27678467
Koebele, Stephanie V; Bimonte-Nelson, Heather A
2017-08-01
Female mammals undergo natural fluctuations in sex steroid hormone levels throughout life. These fluctuations span from early development, to cyclic changes associated with the menstrual or estrous cycle and pregnancy, to marked hormone flux during perimenopause, and a final decline at reproductive senescence. While the transition to reproductive senescence is not yet fully understood, the vast majority of mammals experience this spontaneous, natural phenomenon with age, which has broad implications for long-lived species. Indeed, this post-reproductive life stage, and its transition, involves significant and enduring physiological changes, including considerably altered sex steroid hormone and gonadotropin profiles that impact multiple body systems, including the brain. The endocrine-brain-aging triad is especially noteworthy, as many paths meet and interact. Many of the brain regions affected by aging are also sensitive to changes in ovarian hormone levels, and aging and reproductive senescence are both associated with changes in memory performance. This review explores how menopause is related to cognitive aging, and discusses some of the key neural systems and molecular factors altered with age and reproductive hormone level changes, with an emphasis on brain regions important for learning and memory. Copyright © 2017. Published by Elsevier Inc.
[The function of ERα in male reproductive system].
Dong, Yu-Hang; Wei, Jin-Hua; Li, Zhen
2014-12-01
Estrogen receptors (ERs), including two sub-types ERα and ERβ, belong to the steroid hormone superfamily of nuclear receptors. ERα distributes in the male reproductive system and plays a crucial role in the regulation of male reproduction through estrogen-dependent and -independent ways. In this article, we mainly reviewed the molecular structure, mode of action and location of ERα in the male reproductive system, and explored the mechanism of ERα in regulating the male reproductive system by analyzing different animal models of disrupted ERα.
2012-01-01
The role of steroids in carcinogenesis has become a major concern in environmental protection, biomonitoring, and clinical research. Although historically oestrogen has been related to development of reproductive system, research over the last decade has confirmed its crucial role in the development and homeostasis of other organ systems. As a number of anthropogenic agents are xenoestrogens, environmental health research has focused on oestrogen receptor level disturbances and of aromatase polymorphisms. Oestrogen and xenoestrogens mediate critical points in carcinogenesis by binding to oestrogen receptors, whose distribution is age-, gender-, and tissue-specific. This review brings data about cancer types whose eatiology may be found in environmental exposure to xenoestrogens. Cancer types that have been well documented in literature to be related with environmental exposure include the reproductive system, breast, lung, kidney, pancreas, and brain. The results of our data mining show (a) a significant correlation between exposure to xenoestrogens and increased, gender-related, cancer risk and (b) a need to re-evaluate agents so far defined as endocrine disruptors, as they are also key molecules in carcinogenesis. This revision may be used to further research of cancer aetiology and to improvement of related legislation. Investigation of cancers caused by xenoestrogens may elucidate yet unknown mechanisms also valuable for oncology and the development of new therapies. PMID:22759508
Environmental risk factors and male fertility and reproduction.
Petrelli, Grazia; Mantovani, Alberto
2002-04-01
Several environmental substances and pesticides exert a direct, cytotoxic effect on male germ cells. However, an increasing concern has been raised by compounds that may act through more subtle mechanisms, for example, specific pesticides that are potentially capable of modulating or disrupting the endocrine system. Overall, exposure to pesticides with endocrine-disrupting potential raise a particular concern for male fertility because of the possible occurrence of both effects at low concentrations and additive interactions with other environmental risk factors. Delayed reproductive problems deserve special attention, since experimental data consistently indicate a high vulnerability in the developing male reproductive system. Epidemiologic studies have confirmed an increased risk of conception delay associated with occupational exposure to pesticides. Moreover, an increased risk of spontaneous abortion has been noted among wives of exposed workers.
Dos Santos, Alice Hartmann; Ramos, Aline Camargo; Silveira, Kennia Moura; Kiss, Ana Carolina Inhasz; Longhini, Renata; Diniz, Andréa; de Mello, João Carlos Palazzo; Gerardin, Daniela Cristina Ceccatto
2015-05-26
Trichilia catigua is broadly used in folk medicine due to its mental and physical tonic activities and stimulant effects. In animal models, its antidepressant-like effects have been associated with the dopaminergic (DA) system modulation, which has an important role on maternal behavior and male offspring reproductive development. Since little is known about the adverse effects of the exposure to T. catigua crude extract (CAT) in rats, specially regarding maternal homeostasis and offspring development, the aim of the present study was to evaluate whether CAT exposure may influence maternal toxicity parameters and behavior or disrupt male offspring physical and reproductive development. Dams were treated daily (by gavage) with 400mg/kg of CAT or vehicle (control=CTR) throughout pregnancy and lactation. Fertility and maternal behavior tests were conducted in dams. Male offspring reproductive and behavioral parameters were analyzed. Dams exposed to CAT showed increased pre- and post-implantation losses rates when compared to CTR group. No significant changes regarding maternal behavior or male offspring parameters were observed. In conclusion, maternal exposure to CAT interfered with implantation during the initial phases of pregnancy but did not induce changes on maternal behavior or male offspring reproductive and behavioral parameters. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
PHOTOPERIODISM, REPRODUCTION(PHYSIOLOGY)), (*ENDOCRINE GLANDS , REPRODUCTION(PHYSIOLOGY)), RODENTS, REPRODUCTIVE SYSTEM, EYE, EXCISION, TESTES, OVARIES, ADRENAL GLANDS , THYROID GLAND , IODINE, THIOUREA, RATS, HAMSTERS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Magliulo-Cepriano, L.; Schreibman, M.P.
1999-07-01
In all vertebrates, the neuroendocrine system serves as the primary and essential link between the external and internal environments and a multitude of physiological systems, including the reproductive system. In response to changes in the environment and fluctuations in levels of circulating humoral agents, the neuroendocrine system is able to reverse, maintain or advance physiological events. Endocrine disrupting compounds are believed to wreak havoc on reproduction and development by interfering in the normal flow of information along the brain-pituitary-gonad axis. While the final effects of these compounds may be easily determined in a number of species, utilization of non-traditional researchmore » animals, such as some fishes in which the pattern of information flow along the brain-pituitary-gonad axis has been meticulously detailed and documented, will provide excellent and novel means of elucidating not only the final effects but the cytological, histological and systemic mechanisms of action of these endocrine disruptors. This report presents methods of assessing the effects of endocrine disrupting compounds on a variety of physiological and morphological parameters in fishes.« less
Pandey, Ajai K; Gupta, Anumegha; Tiwari, Meenakshi; Prasad, Shilpa; Pandey, Ashutosh N; Yadav, Pramod K; Sharma, Alka; Sahu, Kankshi; Asrafuzzaman, Syed; Vengayil, Doyil T; Shrivastav, Tulsidas G; Chaube, Shail K
2018-07-01
Stress is deeply rooted in the society and women are frequently exposed to psychological, physical and physiological stressors. Psychological stress disturbs reproductive health by inducing generation of reactive oxygen species (ROS) and thereby oxidative stress (OS). The increased OS may affect physiology of ovary, oocyte quality and cause female reproductive health disorders. To overcome stress-mediated reproductive health disorders in women, shatavari (Asparagus racemosus) is frequently recommended in Ayurvedic system of medicine. Although shatavari is one of the major health tonics and most popular rasayana drugs to treat reproductive ailments of women, underlying mechanism of shatavari action at the level of ovary remains poorly understood. Based on the existing studies, we propose that shatavari may improve female reproductive health complications including hormonal imbalance, polycystic ovarian syndrome (PCOS), follicular growth and development, oocyte quality and infertility possibly by reducing OS level and increasing antioxidants level in the body. Further studies are required to elucidate the mechanism of shatavari actions at the level of ovary and oocyte that directly impacts the reproductive health of women. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Leung, Maxwell C.K.; Phuong, Jimmy; Baker, Nancy C.; Sipes, Nisha S.; Klinefelter, Gary R.; Martin, Matthew T.; McLaurin, Keith W.; Setzer, R. Woodrow; Darney, Sally Perreault; Judson, Richard S.; Knudsen, Thomas B.
2015-01-01
Background: Trends in male reproductive health have been reported for increased rates of testicular germ cell tumors, low semen quality, cryptorchidism, and hypospadias, which have been associated with prenatal environmental chemical exposure based on human and animal studies. Objective: In the present study we aimed to identify significant correlations between environmental chemicals, molecular targets, and adverse outcomes across a broad chemical landscape with emphasis on developmental toxicity of the male reproductive system. Methods: We used U.S. EPA’s animal study database (ToxRefDB) and a comprehensive literature analysis to identify 774 chemicals that have been evaluated for adverse effects on male reproductive parameters, and then used U.S. EPA’s in vitro high-throughput screening (HTS) database (ToxCastDB) to profile their bioactivity across approximately 800 molecular and cellular features. Results: A phenotypic hierarchy of testicular atrophy, sperm effects, tumors, and malformations, a composite resembling the human testicular dysgenesis syndrome (TDS) hypothesis, was observed in 281 chemicals. A subset of 54 chemicals with male developmental consequences had in vitro bioactivity on molecular targets that could be condensed into 156 gene annotations in a bipartite network. Conclusion: Computational modeling of available in vivo and in vitro data for chemicals that produce adverse effects on male reproductive end points revealed a phenotypic hierarchy across animal studies consistent with the human TDS hypothesis. We confirmed the known role of estrogen and androgen signaling pathways in rodent TDS, and importantly, broadened the list of molecular targets to include retinoic acid signaling, vascular remodeling proteins, G-protein coupled receptors (GPCRs), and cytochrome P450s. Citation: Leung MC, Phuong J, Baker NC, Sipes NS, Klinefelter GR, Martin MT, McLaurin KW, Setzer RW, Darney SP, Judson RS, Knudsen TB. 2016. Systems toxicology of male reproductive development: profiling 774 chemicals for molecular targets and adverse outcomes. Environ Health Perspect 124:1050–1061; http://dx.doi.org/10.1289/ehp.1510385 PMID:26662846
Normal Female Reproductive Anatomy
... hyphen, e.g. -historical Searches are case-insensitive Reproductive System, Female, Anatomy Add to My Pictures View /Download : ... 1500x1575 View Download Large: 3000x3150 View Download Title: Reproductive System, Female, Anatomy Description: Anatomy of the female reproductive ...
Reproduction in the space environment: Part I. Animal reproductive studies
NASA Technical Reports Server (NTRS)
Santy, P. A.; Jennings, R. T.; Craigie, D.
1990-01-01
Mankind's exploration and colonization of the frontier of space will ultimately depend on men's and women's ability to live, work, and reproduce in the space environment. This paper reviews animal studies, from microorganisms to mammals, done in space or under space-simulated conditions, which identify some of the key areas which might interfere with human reproductive physiology and/or embryonic development. Those space environmental factors which impacted almost all species included: microgravity, artificial gravity, radiation, and closed life support systems. These factors may act independently and in combination to produce their effects. To date, there have been no studies which have looked at the entire process of reproduction in any animal species. This type of investigation will be critical in understanding and preventing the problems which will affect human reproduction. Part II will discuss these problems directly as they relate to human physiology.
Indigenous peoples of North America: environmental exposures and reproductive justice.
Hoover, Elizabeth; Cook, Katsi; Plain, Ron; Sanchez, Kathy; Waghiyi, Vi; Miller, Pamela; Dufault, Renee; Sislin, Caitlin; Carpenter, David O
2012-12-01
Indigenous American communities face disproportionate health burdens and environmental health risks compared with the average North American population. These health impacts are issues of both environmental and reproductive justice. In this commentary, we review five indigenous communities in various stages of environmental health research and discuss the intersection of environmental health and reproductive justice issues in these communities as well as the limitations of legal recourse. The health disparities impacting life expectancy and reproductive capabilities in indigenous communities are due to a combination of social, economic, and environmental factors. The system of federal environmental and Indian law is insufficient to protect indigenous communities from environmental contamination. Many communities are interested in developing appropriate research partnerships in order to discern the full impact of environmental contamination and prevent further damage. Continued research involving collaborative partnerships among scientific researchers, community members, and health care providers is needed to determine the impacts of this contamination and to develop approaches for remediation and policy interventions.
Indigenous Peoples of North America: Environmental Exposures and Reproductive Justice
Cook, Katsi; Plain, Ron; Sanchez, Kathy; Waghiyi, Vi; Miller, Pamela; Dufault, Renee; Sislin, Caitlin; Carpenter, David O.
2012-01-01
Background: Indigenous American communities face disproportionate health burdens and environmental health risks compared with the average North American population. These health impacts are issues of both environmental and reproductive justice. Objectives: In this commentary, we review five indigenous communities in various stages of environmental health research and discuss the intersection of environmental health and reproductive justice issues in these communities as well as the limitations of legal recourse. Discussion: The health disparities impacting life expectancy and reproductive capabilities in indigenous communities are due to a combination of social, economic, and environmental factors. The system of federal environmental and Indian law is insufficient to protect indigenous communities from environmental contamination. Many communities are interested in developing appropriate research partnerships in order to discern the full impact of environmental contamination and prevent further damage. Conclusions: Continued research involving collaborative partnerships among scientific researchers, community members, and health care providers is needed to determine the impacts of this contamination and to develop approaches for remediation and policy interventions. PMID:22899635
Barreix, Maria; Tunçalp, Özge; Mutombo, Namuunda; Adegboyega, Ayotunde A; Say, Lale
2017-05-01
Universal access to sexual and reproductive health remains part of the unfinished business of global development in Africa. To achieve it, health interventions should be monitored using programmatic indicators. WHO's Strengthening Measurement of Reproductive Health Indicators in Africa initiative, implemented in Ghana, Nigeria, Kenya, Uganda, and Zimbabwe, aimed to improve national information systems for routine monitoring of reproductive health indicators. Participating countries developed action plans employing a two-pronged strategy: (1) revising, standardizing, and harmonizing existing reproductive health indicators captured through routine information-systems; and (2) building data-collection capacity through training and supervision at select pilot sites. Country teams evaluated existing and new indicators, and outlined barriers to strengthening routine measurement. Activities included updating abortion-care guidelines (spontaneous and induced abortions), providing training on laws surrounding induced abortions, and improving feedback mechanisms. The country teams updated monitoring and evaluation frameworks, and attempted to build recording/reporting capacity in selected pilot areas. Barriers to implementing the initiative that were encountered included restrictive induced-abortion laws, staff turn-over, and administrative delays, including low capacity among healthcare staff and competing priorities for staff time. The areas identified for further improvement were up-scaling programs to a national level, creating scorecards to record data, increasing collaborations with the private sector, conducting related costing exercises, and performing ex-post evaluations. © 2017 World Health Organization; licensed by Wiley on behalf of International Federation of Gynecology and Obstetrics.
Pilot production system cost/benefit analysis: Digital document storage project
NASA Technical Reports Server (NTRS)
1989-01-01
The Digital Document Storage (DDS)/Pilot Production System (PPS) will provide cost effective electronic document storage, retrieval, hard copy reproduction, and remote access for users of NASA Technical Reports. The DDS/PPS will result in major benefits, such as improved document reproduction quality within a shorter time frame than is currently possible. In addition, the DDS/PPS will provide an important strategic value through the construction of a digital document archive. It is highly recommended that NASA proceed with the DDS Prototype System and a rapid prototyping development methodology in order to validate recent working assumptions upon which the success of the DDS/PPS is dependent.
CONFOCAL MICROSCOPY SYSTEM PERFORMANCE: AXIAL RESOLUTION
Abstract
Confocal Microscopy System Performance: Axial resolution.
Robert M. Zucker, PhD
Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Re...
Different ontogenetic processes promote dicliny in Ficus L. (Moraceae)
NASA Astrophysics Data System (ADS)
Basso-Alves, João Paulo; Pereira, Rodrigo Augusto Santinelo; Peng, Yang-Qiong; Teixeira, Simone Pádua
2014-05-01
The absence of reproductive organs in flowers may ontogenetically arise from inception or by abortion during development. Ficus L., a species-rich genus of angiosperms, is an interesting model for floral developmental studies because of the diversity of sexual systems it contains. This study compares the floral morphology of Ficus citrifolia (monoecious), Ficus religiosa (monoecious), Ficus racemosa (secondarily monoecious), and Ficus hispida (gynodioecious) across development to establish the ontogenetic pathways that result in diclinous flowers. Figs were collected at various developmental stages and were prepared for surface (scanning electron microscopy) and histological (light microscopy) analyses. Dicliny in Ficus is defined by stamen absence from inception in pistillate flowers and either pistil absence from inception (F. citrifolia, F. racemosa and F. religiosa) or by abortion (F. hispida) in staminate flowers. The perianth is formed by a single whorl of sepals, as found in other families related to Moraceae. The gynoecium is tubular during development, a condition that may be related with pseudomonomery. The staminate and neutral flowers in F. hispida develop by similar mechanisms. The diversity in the sexual systems in Ficus results from combinations of different floral morphs (dicliny), which originate from both previously established ontogenetic mechanisms (loss of reproductive organ function by abortion or from inception). These mechanisms act independently of phylogenetic proximity or mechanisms of sex system evolution in Ficus. Other aspects of floral development observed in Ficus are discussed in relation to their systematic position and reproductive biology.
Sifakis, Stavros; Androutsopoulos, Vasilis P; Tsatsakis, Aristeidis M; Spandidos, Demetrios A
2017-04-01
Endocrine disrupting chemicals (EDCs) comprise a group of chemical compounds that have been examined extensively due to the potential harmful effects in the health of human populations. During the past decades, particular focus has been given to the harmful effects of EDCs to the reproductive system. The estimation of human exposure to EDCs can be broadly categorized into occupational and environmental exposure, and has been a major challenge due to the structural diversity of the chemicals that are derived by many different sources at doses below the limit of detection used by conventional methodologies. Animal and in vitro studies have supported the conclusion that endocrine disrupting chemicals affect the hormone dependent pathways responsible for male and female gonadal development, either through direct interaction with hormone receptors or via epigenetic and cell-cycle regulatory modes of action. In human populations, the majority of the studies point towards an association between exposure to EDCs and male and/or female reproduction system disorders, such as infertility, endometriosis, breast cancer, testicular cancer, poor sperm quality and/or function. Despite promising discoveries, a causal relationship between the reproductive disorders and exposure to specific toxicants is yet to be established, due to the complexity of the clinical protocols used, the degree of occupational or environmental exposure, the determination of the variables measured and the sample size of the subjects examined. Future studies should focus on a uniform system of examining human populations with regard to the exposure to specific EDCs and the direct effect on the reproductive system. Copyright © 2017 Elsevier B.V. All rights reserved.
Species Comparison of the Role of p38 MAP Kinase in the Female Reproductive System.
Radi, Zaher A; Marusak, Rosemary A; Morris, Dale L
2009-06-01
The p38 mitogen-activated protein kinases (MAPKs) are members of discrete signal transduction pathways that have significant regulatory roles in a variety of biological processes, depending on the cell, tissue and organ type. p38 MAPKs are involved in inflammation, cell growth and differentiation and cell cycle. In the female reproductive system, p38 MAPKs are known to regulate various aspects of the reproductive process such as mammalian estrous and menstrual cycles as well as early pregnancy and parturition. p38 MAPKs have also been implicated in alterations and pathologies observed in the female reproductive system. Therefore, pharmacologic modulation of p38 MAPKs, and inter-connected signaling pathways (e.g., estrogen receptor signaling, c-fos, c-jun), may influence reproductive physiology and function. This article provides a critical, comparative review of available data on the roles of p38 MAPKs in the mammalian female reproductive system and in reproductive pathophysiology in humans and preclinical species. We first introduce fundamental differences and similarities of the mammalian female reproductive system that should be considered by toxicologists and toxicologic pathologists when assessing the effects of new pharmacologic agents on the female reproductive system. We then explore in detail the known roles for p38 MAPKs and related molecules in female reproduction. This foundation is then extended to pathological conditions in which p38 MAPKs are thought to play an integral role.
Kisspeptin modulates sexual and emotional brain processing in humans
Comninos, Alexander N.; Wall, Matthew B.; Demetriou, Lysia; Shah, Amar J.; Clarke, Sophie A.; Narayanaswamy, Shakunthala; Nesbitt, Alexander; Izzi-Engbeaya, Chioma; Prague, Julia K.; Abbara, Ali; Ratnasabapathy, Risheka; Salem, Victoria; Nijher, Gurjinder M.; Jayasena, Channa N.; Tanner, Mark; Bassett, Paul; Mehta, Amrish; Rabiner, Eugenii A.; Hönigsperger, Christoph; Silva, Meire Ribeiro; Brandtzaeg, Ole Kristian; Wilson, Steven Ray; Brown, Rachel C.; Thomas, Sarah A.; Bloom, Stephen R.; Dhillo, Waljit S.
2017-01-01
BACKGROUND. Sex, emotion, and reproduction are fundamental and tightly entwined aspects of human behavior. At a population level in humans, both the desire for sexual stimulation and the desire to bond with a partner are important precursors to reproduction. However, the relationships between these processes are incompletely understood. The limbic brain system has key roles in sexual and emotional behaviors, and is a likely candidate system for the integration of behavior with the hormonal reproductive axis. We investigated the effects of kisspeptin, a recently identified key reproductive hormone, on limbic brain activity and behavior. METHODS. Using a combination of functional neuroimaging and hormonal and psychometric analyses, we compared the effects of kisspeptin versus vehicle administration in 29 healthy heterosexual young men. RESULTS. We demonstrated that kisspeptin administration enhanced limbic brain activity specifically in response to sexual and couple-bonding stimuli. Furthermore, kisspeptin’s enhancement of limbic brain structures correlated with psychometric measures of reward, drive, mood, and sexual aversion, providing functional significance. In addition, kisspeptin administration attenuated negative mood. CONCLUSIONS. Collectively, our data provide evidence of an undescribed role for kisspeptin in integrating sexual and emotional brain processing with reproduction in humans. These results have important implications for our understanding of reproductive biology and are highly relevant to the current pharmacological development of kisspeptin as a potential therapeutic agent for patients with common disorders of reproductive function. FUNDING. National Institute for Health Research (NIHR), Wellcome Trust (Ref 080268), and the Medical Research Council (MRC). PMID:28112678
Peixoto, Alexandre A.; Vigoder, Felipe M.; Bruno, Rafaela V.; Soares, Maurilio J.
2013-01-01
Background The male reproductive system of insects can have several tissues responsible for the secretion of seminal fluid proteins (SFPs), such as testes, accessory glands, seminal vesicles, ejaculatory duct and ejaculatory bulb. The SFPs are transferred during mating and can induce several physiological and behavioral changes in females, such as increase in oviposition and decrease in sexual receptivity after copulation. The phlebotomine Lutzomyia longipalpis is the main vector of visceral leishmaniasis. Despite its medical importance, little is known about its reproductive biology. Here we present morphological aspects of the male L. longipalpis reproductive system by light, scanning and transmission electron microscopy, and compare the mating frequency of both virgin and previously mated females. Results The male L. longipalpis reproductive system is comprised by a pair of oval-shaped testes linked to a seminal vesicle by vasa deferentia. It follows an ejaculatory duct with an ejaculatory pump (a large bulb enveloped by muscles and associated to tracheas). The terminal endings of the vasa deferentia are inserted into the seminal vesicle by invaginations of the seminal vesicle wall, which is composed by a single layer of gland cells, with well-developed endoplasmic reticulum profiles and secretion granules. Our data suggest that the seminal vesicle acts both as a spermatozoa reservoir and as an accessory gland. Mating experiments support this hypothesis, revealing a decrease in mating frequency after copulation that indicates the effect of putative SFPs. Conclusion Ultrastructural features of the L. longipalpis male seminal vesicle indicated its possible role as an accessory gland. Behavioral observations revealed a reduction in mating frequency of copulated females. Together with transcriptome analyses from male sandfly reproductive organs identifying ESTs encoding orthologs of SFPs, these data indicate the presence of putative L. longipalpis SFPs reducing sexual mating frequency of copulated females. PMID:24058637
Evolution and functional divergence of NLRP genes in mammalian reproductive systems
2009-01-01
Background NLRPs (Nucleotide-binding oligomerization domain, Leucine rich Repeat and Pyrin domain containing Proteins) are members of NLR (Nod-like receptors) protein family. Recent researches have shown that NLRP genes play important roles in both mammalian innate immune system and reproductive system. Several of NLRP genes were shown to be specifically expressed in the oocyte in mammals. The aim of the present work was to study how these genes evolved and diverged after their duplication, as well as whether natural selection played a role during their evolution. Results By using in silico methods, we have evaluated the evolution and functional divergence of NLRP genes, in particular of mouse reproduction-related Nlrp genes. We found that (1) major NLRP genes have been duplicated before the divergence of mammals, with certain lineage-specific duplications in primates (NLRP7 and 11) and in rodents (Nlrp1, 4 and 9 duplicates); (2) tandem duplication events gave rise to a mammalian reproduction-related NLRP cluster including NLRP2, 4, 5, 7, 8, 9, 11, 13 and 14 genes; (3) the function of mammalian oocyte-specific NLRP genes (NLRP4, 5, 9 and 14) might have diverged during gene evolution; (4) recent segmental duplications concerning Nlrp4 copies and vomeronasal 1 receptor encoding genes (V1r) have been undertaken in the mouse; and (5) duplicates of Nlrp4 and 9 in the mouse might have been subjected to adaptive evolution. Conclusion In conclusion, this study brings us novel information on the evolution of mammalian reproduction-related NLRPs. On the one hand, NLRP genes duplicated and functionally diversified in mammalian reproductive systems (such as NLRP4, 5, 9 and 14). On the other hand, during evolution, different lineages adapted to develop their own NLRP genes, particularly in reproductive function (such as the specific expansion of Nlrp4 and Nlrp9 in the mouse). PMID:19682372
Yoshida-Noro, Chikako; Tochinai, Shin
2010-01-01
Enchytraeus japonensis is a small oligochaete species that proliferates asexually via fragmentation and regeneration. As sexual reproduction can also be induced, it is a good model system for the study of both regenerative and germline stem cells. It has been shown by histological study that putative mesodermal stem cells called neoblasts, and dedifferentiated epidermal and endodermal cells are involved in blastema formation. Recently, we isolated three region-specific marker genes expressed in the digestive tract and showed by in situ hybridization that morphallactic as well as epimorphic regulation of the body patterning occurs during regeneration. We also cloned two vasa-related genes and analyzed their expression during development and in mature worms that undergo sexual reproduction. The results arising form these studies suggest that the origin and development of germline stem cells and neoblasts may be independent. Furthermore, we carried out functional analysis using RNA interference (RNAi) and showed that a novel gene termed grimp is required for mesodermal cell proliferation at the initial stages of regeneration. These findings indicate that the stem cell system in E. japonensis is regulated by both internal and external environmental factors.
Giordano, J O; Fricke, P M; Wiltbank, M C; Cabrera, V E
2011-12-01
Because the reproductive performance of lactating dairy cows influences the profitability of dairy operations, predicting the future reproductive and economic performance of dairy herds through decision support systems would be valuable to dairy producers and consultants. In this study, we present a highly adaptable tool created based on a mathematical model combining Markov chain simulation with partial budgeting to obtain the net present value (NPV; $/cow per year) of different reproductive management programs. The growing complexity of reproductive programs used by dairy farms demands that new decision support systems precisely reflect the events that occur on the farm. Therefore, the model requires productive, reproductive, and economic input data used for simulation of farm conditions to account for all factors related to reproductive management that increase costs and generate revenue. The economic performance of 3 different reproductive programs can be simultaneously compared with the current model. A program utilizing 100% visual estrous detection (ED) for artificial insemination (AI) is used as a baseline for comparison with 2 other programs that may include 100% timed AI (TAI) as well as any combination of TAI and ED. A case study is presented in which the model was used to compare 3 different reproductive management strategies (100% ED baseline compared with two 100% TAI options) using data from a commercial farm in Wisconsin. Sensitivity analysis was then used to assess the effect of varying specific reproductive parameters on the NPV. Under the simulated conditions of the case study, the model indicated that the two 100% TAI programs were superior to the 100% ED program and, of the 100% TAI programs, the one with the higher conception rate (CR) for resynchronized AI services was economically superior despite having higher costs and a longer interbreeding interval. A 4% increase in CR for resynchronized AI was sufficient for the inferior 100% TAI to outperform the superior program. Adding ED to the 100% TAI programs was only beneficial for the program with the lower CR. The improvement in service rate required for the 100% ED program to have the same NPV as the superior 100% TAI program was 12%. The decision support system developed in this study is a valuable tool that may be used to assist dairy producers and industry consultants in selecting the best farm-specific reproductive management strategy. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Improving education and resources for health care providers.
Paul, M; Welch, L
1993-01-01
Workers and citizens are turning increasingly to the health care system for information about occupational and environmental reproductive hazards, yet most primary care providers and specialists know little about the effects of occupational/environmental toxicants on the reproductive system or how to evaluate and manage patients at potential risk. Although it is unrealistic to expect all clinicians to become experts in this area, practitioners should know how to take a basic screening history, identify patients at potential risk, and make appropriate referrals. At present, occupational and environmental health issues are not well integrated into health professional education in the United States, and clinical information and referral resources pertaining to reproductive hazards are inadequate. In addressing these problems, the conference "Working Group on Health Provider Education and Resources" made several recommendations that are detailed in this report. Short-term goals include enhancement of existing expertise and resources at a regional level and better integration of information on occupational/environmental reproductive hazards into curricula, meetings, and publications of medical and nursing organizations. Longer term goals include development of a comprehensive, single-access information and referral system for clinicians and integration of occupational and environmental medicine into formal health professional education curricula at all levels. PMID:8243391
The Blind, From Braille to the Present.
ERIC Educational Resources Information Center
Truquet, Monique
1980-01-01
Traces the historical development of processing information for the blind from the system devised by Barbier to present systems of producing Braille documents using computers. Cites the impact of microprocessors and outlines possibilities for Braille reproductions in the future. (GS)
Rouhana, Labib; Tasaki, Junichi; Saberi, Amir; Newmark, Phillip A
2017-06-01
Cytoplasmic polyadenylation is a mechanism of mRNA regulation prevalent in metazoan germ cells; it is largely dependent on Cytoplasmic Polyadenylation Element Binding proteins (CPEBs). Two CPEB homologs were identified in the planarian Schmidtea mediterranea. Smed-CPEB1 is expressed in ovaries and yolk glands of sexually mature planarians, and required for oocyte and yolk gland development. In contrast, Smed-CPEB2 is expressed in the testes and the central nervous system; its function is required for spermatogenesis as well as non-autonomously for development of ovaries and accessory reproductive organs. Transcriptome analysis of CPEB knockdown animals uncovered a comprehensive collection of molecular markers for reproductive structures in S. mediterranea, including ovaries, testes, yolk glands, and the copulatory apparatus. Analysis by RNA interference revealed contributions for a dozen of these genes during oogenesis, spermatogenesis, or capsule formation. We also present evidence suggesting that Smed-CPEB2 promotes translation of Neuropeptide Y-8, a prohormone required for planarian sexual maturation. These findings provide mechanistic insight into potentially conserved processes of germ cell development, as well as events involved in capsule deposition by flatworms. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
2017-04-01
The reporting of research in a manner that allows reproduction in subsequent investigations is important for scientific progress. Several details of the recent study by Patrizi et al., 'Comparison between low-cost marker-less and high-end marker-based motion capture systems for the computer-aided assessment of working ergonomics', are absent from the published manuscript and make reproduction of findings impossible. As new and complex technologies with great promise for ergonomics develop, new but surmountable challenges for reporting investigations using these technologies in a reproducible manner arise. Practitioner Summary: As with traditional methods, scientific reporting of new and complex ergonomics technologies should be performed in a manner that allows reproduction in subsequent investigations and supports scientific advancement.
Male Reproductive System (For Teens)
... genes come from the father's sperm and the mother's egg, which are produced by the male and female reproductive systems. What Is the Male Reproductive System? Most species have two sexes: male and female. Each sex has its own ...
CONFOCAL MICROSCOPY SYSTEM PERFORMANCE: QA TESTS, QUANTITATION AND SPECTROSCOPY
Confocal Microscopy System Performance: QA tests, Quantitation and Spectroscopy.
Robert M. Zucker 1 and Jeremy M. Lerner 2,
1Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research Development, U.S. Environmen...
Page, Robert E; Scheiner, Ricarda; Erber, Joachim; Amdam, Gro V
2006-01-01
How does complex social behavior evolve? What are the developmental building blocks of division of labor and specialization, the hallmarks of insect societies? Studies have revealed the developmental origins in the evolution of division of labor and specialization in foraging worker honeybees, the hallmarks of complex insect societies. Selective breeding for a single social trait, the amount of surplus pollen stored in the nest (pollen hoarding) revealed a phenotypic architecture of correlated traits at multiple levels of biological organization in facultatively sterile female worker honeybees. Verification of this phenotypic architecture in "wild-type" bees provided strong support for a "pollen foraging syndrome" that involves increased senso-motor responses, motor activity, associative learning, reproductive status, and rates of behavioral development, as well as foraging behavior. This set of traits guided further research into reproductive regulatory systems that were co-opted by natural selection during the evolution of social behavior. Division of labor, characterized by changes in the tasks performed by bees, as they age, is controlled by hormones linked to ovary development. Foraging specialization on nectar and pollen results also from different reproductive states of bees where nectar foragers engage in pre-reproductive behavior, foraging for nectar for self-maintenance, while pollen foragers perform foraging tasks associated with reproduction and maternal care, collecting protein.
NASA Astrophysics Data System (ADS)
Zhao, Chunyan; Xu, Shihong; Feng, Chengcheng; Liu, Yifan; Yang, Yang; Wang, Yanfeng; Xiao, Yongshuang; Song, Zongcheng; Liu, Qinghua; Li, Jun
2017-10-01
Turbots (Schophthalmus maximus), one of the most important economic marine flatfish species, fail to undergo final spawning and spermiation naturally under artificial farming conditions. In vertebrates, reproduction is regulated by the brain-pituitary-gonadal axis (BPG-axis), and gonadotropin releasing hormone (GnRH) is one of its key components. Therefore, to better understand the physiology of reproduction in the turbot, three of the genes encoding GnRH subtypes—sbGnRH, cGnRH-II and sGnRH—were cloned and sequenced by isolating the cDNA sequences. The localizations and patterns of expression of their mRNAs were also evaluated during seasonal gonadal development. All three mRNAs were expressed abundantly in the brain; sbGnRH and sGnRH mRNAs were also detected in the gonads and pituitary gland, and sbGnRH expression was much higher than that of sGnRH, indicating the critical role of sbGnRH in regulating the BPG-axis. Moreover, the brain expression patterns of sbGnRH and sGnRH mRNAs showed an increased trend during gonadal development, peaking in mature stages. This indicated the direct regulation of gonadal development by the GnRH system. In addition, cGnRH-II mRNA expression showed no significant variations, suggesting that cGnRH-II is not critically involved in the control of reproduction. Further, the mRNA abundances of the three GnRH forms in the breeding season were significantly higher than those in immature and post-breeding stages in all analyzed brain areas. Therefore, we propose that sbGnRH is the most important hormone for the regulation of reproduction in turbot via the BPG-axis. These results will help in better understanding the reproductive endocrine mechanisms of turbots and lay the groundwork for additional studies aimed at comparing the reproductive physiology of wild individuals with those raised under artificial conditions.
Zebrafish: A Versatile Animal Model for Fertility Research.
Hoo, Jing Ying; Kumari, Yatinesh; Shaikh, Mohd Farooq; Hue, Seow Mun; Goh, Bey Hing
2016-01-01
The utilization of zebrafish in biomedical research is very common in the research world nowadays. Today, it has emerged as a favored vertebrate organism for the research in science of reproduction. There is a significant growth in amount numbers of scientific literature pertaining to research discoveries in reproductive sciences in zebrafish. It has implied the importance of zebrafish in this particular field of research. In essence, the current available literature has covered from the very specific brain region or neurons of zebrafish, which are responsible for reproductive regulation, until the gonadal level of the animal. The discoveries and findings have proven that this small animal is sharing a very close/similar reproductive system with mammals. More interestingly, the behavioral characteristics and along with the establishment of animal courtship behavior categorization in zebrafish have laid an even stronger foundation and firmer reason on the suitability of zebrafish utilization in research of reproductive sciences. In view of the immense importance of this small animal for the development of reproductive sciences, this review aimed at compiling and describing the proximate close similarity of reproductive regulation on zebrafish and human along with factors contributing to the infertility, showing its versatility and its potential usage for fertility research.
Zebrafish: A Versatile Animal Model for Fertility Research
Hoo, Jing Ying; Kumari, Yatinesh; Shaikh, Mohd Farooq; Hue, Seow Mun
2016-01-01
The utilization of zebrafish in biomedical research is very common in the research world nowadays. Today, it has emerged as a favored vertebrate organism for the research in science of reproduction. There is a significant growth in amount numbers of scientific literature pertaining to research discoveries in reproductive sciences in zebrafish. It has implied the importance of zebrafish in this particular field of research. In essence, the current available literature has covered from the very specific brain region or neurons of zebrafish, which are responsible for reproductive regulation, until the gonadal level of the animal. The discoveries and findings have proven that this small animal is sharing a very close/similar reproductive system with mammals. More interestingly, the behavioral characteristics and along with the establishment of animal courtship behavior categorization in zebrafish have laid an even stronger foundation and firmer reason on the suitability of zebrafish utilization in research of reproductive sciences. In view of the immense importance of this small animal for the development of reproductive sciences, this review aimed at compiling and describing the proximate close similarity of reproductive regulation on zebrafish and human along with factors contributing to the infertility, showing its versatility and its potential usage for fertility research. PMID:27556045
[Causes and Factors of Male Infertility].
Kolesnikova, L I; Kolesnikov, S I; Kurashova, N A; Bairova, T A
2015-01-01
The preservation of reproductive health of the population is an important factor of demographic policy of the state. According to some authors from 14 to 30% of couples of reproductive age suffer from infertility, malefactor in such marriages is detected in more than half of the cases. As you know, in recent years there has been a significant deterioration in the main indicators of reproductive function of men. Increased the number of andrological diseases, morphological disorders of the male reproductive system, almost halved the production of sperm in men of reproductive age. The reason probably lies behind a whole range ofstressfactors, such as medical ignorance, uncontrolled and inappropriate use of medication, metabolic disturbances, lack of vitamins and minerals, the impact of industrial pollutants, as well as the growth of addictive disorders (alcoholism, smoking and drug addiction). The forms of infertility differ according to its etiology and severity from minor changes to complete spermatogenesis dysfunction of the gonads, and can also occur due to genetic disorders. The lack of analysis of the relationship between clinical and genetic-biochemical components in men with infertility makes it impossible to understand the pathogenesis of infertility and to assess the risks of male infertility. High level of current medicine does not always guarantee an identification of the cause of male infertility. The article analyzes data from the review of specialized literature on the diagnosis and etiopathogenesis of male infertility. Frequency and clinical signs of pathology of the male reproductive system depend on the combinatorial effects of environmental influences, manifested most often in mutually reinforcing effect. A combination of several, seemed to be imperceptible factors makes the risk of development of male reproductive pathology very high. This situation compels specialists to conduct comprehensive studies on the men reproductive potential.
Newlin, David B
2002-04-01
A new theory of substance use disorders is proposed-the SPFit theory-that is based on evolutionary biology and adaptive systems. Self-perceived survival ability and reproductive fitness (SPFit) is proposed as a human psychobiological construct that prioritizes and organizes (i.e. motivates) behavior, but is highly vulnerable to temporary, artificial activation by drugs of abuse. Autoshaping/sign-tracking/feature positive phenomena are proposed to underlie the development of craving and expectations about drugs as the individual learns that abused drugs will easily and reliably inflate SPFit. The cortico-mesolimbic dopamine system and its modulating interconnections are viewed as the biological substrate of SPFit; it is proposed to be a survival and reproductive motivation system rather than a reward center or reward pathway. Finally, the concept of modularity of mind is applied to the SPFit construct. Although considerable empirical data are consistent with the theory, new research is needed to test specific hypotheses derived from SPFit theory.
Özyurt, Nurcan; Candan, Selami; Suludere, Zekiye
2013-01-01
The male reproductive system of Dolycoris baccarum (Linnaeus 1758) is studied morphologically and histologically using both light and scanning electron microscopes (SEM). The reproductive system of the male D. baccarum consists of a pair of testis, a pair of vas deferens, a pair of seminal vesicles, accessory glands (mesadenia, ectadenia), a bulbus ejaculatorius, a pair of ectodermal sacs, and a ductus ejaculatorius. The number of testicular follicles varies from four to six. The testicular follicles have three different development zones (growth zone, maturation zone, differentiation zone). The testes are connected to the seminal vesicles by the vas deferens. Vas deferens and seminal vesicles, which are fine-long and cylindrical. The seminal vesicle is connected with bulbus ejaculatorius which is balloon-shaped and surrounded with accessory glands. The bulbus ejaculatorius is continuous with ductus ejaculatorius which connected to the aedeagus. Copyright © 2012 Elsevier Ltd. All rights reserved.
High-speed reference-beam-angle control technique for holographic memory drive
NASA Astrophysics Data System (ADS)
Yamada, Ken-ichiro; Ogata, Takeshi; Hosaka, Makoto; Fujita, Koji; Okuyama, Atsushi
2016-09-01
We developed a holographic memory drive for next-generation optical memory. In this study, we present the key technology for achieving a high-speed transfer rate for reproduction, that is, a high-speed control technique for the reference beam angle. In reproduction in a holographic memory drive, there is the issue that the optimum reference beam angle during reproduction varies owing to distortion of the medium. The distortion is caused by, for example, temperature variation, beam irradiation, and moisture absorption. Therefore, a reference-beam-angle control technique to position the reference beam at the optimum angle is crucial. We developed a new optical system that generates an angle-error-signal to detect the optimum reference beam angle. To achieve the high-speed control technique using the new optical system, we developed a new control technique called adaptive final-state control (AFSC) that adds a second control input to the first one derived from conventional final-state control (FSC) at the time of angle-error-signal detection. We established an actual experimental system employing AFSC to achieve moving control between each page (Page Seek) within 300 µs. In sequential multiple Page Seeks, we were able to realize positioning to the optimum angles of the reference beam that maximize the diffracted beam intensity. We expect that applying the new control technique to the holographic memory drive will enable a giga-bit/s-class transfer rate.
Beadex Function in the Motor Neurons Is Essential for Female Reproduction in Drosophila melanogaster
Kairamkonda, Subhash; Nongthomba, Upendra
2014-01-01
Drosophila melanogaster has served as an excellent model system for understanding the neuronal circuits and molecular mechanisms regulating complex behaviors. The Drosophila female reproductive circuits, in particular, are well studied and can be used as a tool to understand the role of novel genes in neuronal function in general and female reproduction in particular. In the present study, the role of Beadex, a transcription co-activator, in Drosophila female reproduction was assessed by generation of mutant and knock down studies. Null allele of Beadex was generated by transposase induced excision of P-element present within an intron of Beadex gene. The mutant showed highly compromised reproductive abilities as evaluated by reduced fecundity and fertility, abnormal oviposition and more importantly, the failure of sperm release from storage organs. However, no defect was found in the overall ovariole development. Tissue specific, targeted knock down of Beadex indicated that its function in neurons is important for efficient female reproduction, since its neuronal knock down led to compromised female reproductive abilities, similar to Beadex null females. Further, different neuronal class specific knock down studies revealed that Beadex function is required in motor neurons for normal fecundity and fertility of females. Thus, the present study attributes a novel and essential role for Beadex in female reproduction through neurons. PMID:25396431
Adipokines in human reproduction.
Dupont, Joëlle; Pollet-Villard, Xavier; Reverchon, Maxime; Mellouk, Namya; Levy, Rachel
2015-10-01
Adipose tissue communicates with other central and peripheral organs by the synthesis and release of substances called adipokines. The most studied adipokine is leptin but others have been recently identified including resistin, adiponectin, chemerin, omentin and visfatin. These adipokines have a critical role in the development of obesity-related complications and inflammatory conditions. However, they are also involved in other functions in the organism including reproductive functions. Indeed, many groups have demonstrated that adipokine receptors, such as adiponectin and chemerin, but also adipokines themselves (adiponectin, chemerin, resistin, visfatin and omentin) are expressed in human peripheral reproductive tissues and that these adipokines are likely to exert direct effects on these tissues. After a brief description of these new adipokines, an overview of their actions in different human reproductive organs (hypothalamus, pituitary, ovary, testis, uterus and placenta) will be presented. Finally, comments will be made on the eventual alterations of these adipokines in reproductive disorders, with special attention to polycystic ovary syndrome, a disease characterized by dysfunction of gonadal axis and systemic nerve endocrine metabolic network with a prevalence of up to 10% in women of reproductive age.
In response to legislation, the USEPA is developing assessment tools for identifying chemicals likely to cause sublethal effects on reproduction and reproductive development with ultimate adverse impacts on fish populations. While fecundity and fertility data from short-term adul...
The role of adiponectin in reproduction: from polycystic ovary syndrome to assisted reproduction
Michalakis, Konstantinos G.; Segars, James H.
2011-01-01
Objective To summarize the effects of the adipokine adiponectin on the reproductive endocrine system, from the hypothalamic-pituitary axis to the gonads and target tissues of the reproductive system. Design A Medline computer search was performed to identify relevant articles. Setting Research institution. Intervention(s) None. Result(s) Adiponectin is a hormone secreted by adipose tissue that acts to reduce insulin resistance and atherogenic damage, but it also exerts actions in other tissues. Adiponectin mediates its actions in the periphery mainly via two receptors, AdipoR1 and AdipoR2. Adiponectin receptors are present in many reproductive tissues, including the central nervous system, ovaries, oviduct, endometrium, and testes. Adiponectin influences gonadotropin release, normal pregnancy, and assisted reproduction outcomes. Conclusion(s) Adiponectin, a beneficial adipokine, represents a major link between obesity and reproduction. Higher levels of adiponectin are associated with improved menstrual function and better outcomes in assisted reproductive cycles. PMID:20561616
Schlotz, Nina; Roulin, Anne; Ebert, Dieter; Martin-Creuzburg, Dominik
2016-11-01
Eicosanoids derive from essential polyunsaturated fatty acids (PUFA) and play crucial roles in immunity, development, and reproduction. However, potential links between dietary PUFA supply and eicosanoid biosynthesis are poorly understood, especially in invertebrates. Using Daphnia magna and its bacterial parasite Pasteuria ramosa as model system, we studied the expression of genes coding for key enzymes in eicosanoid biosynthesis and of genes related to oogenesis in response to dietary arachidonic acid and eicosapentaenoic acid in parasite-exposed and non-exposed animals. Gene expression related to cyclooxygenase activity was especially responsive to the dietary PUFA supply and parasite challenge, indicating a role for prostanoid eicosanoids in immunity and reproduction. Vitellogenin gene expression was induced upon parasite exposure in all food treatments, suggesting infection-related interference with the host's reproductive system. Our findings highlight the potential of dietary PUFA to modulate the expression of key enzymes involved in eicosanoid biosynthesis and reproduction and thus underpin the idea that the dietary PUFA supply can influence invertebrate immune functions and host-parasite interactions. Copyright © 2016 Elsevier Inc. All rights reserved.
O'Neill, C J; Bishop-Hurley, G J; Williams, P J; Reid, D J; Swain, D L
2014-12-10
Reproductive efficiency is an important determinant of profitable cattle breeding systems and the success of assisted reproductive techniques (ART) in wildlife conservation programs. Methods of estrous detection used in intensive beef and dairy cattle systems lack accuracy and remain the single biggest issue for improvement of reproductive rates and such methods are not practical for either large-scale extensive beef cattle enterprises or free-living mammalian species. Recent developments in UHF (ultra high frequency) proximity logger telemetry devices have been used to provide a continuous pair-wise measure of associations between individual animals for both livestock and wildlife. The objective of this study was to explore the potential of using UHF telemetry to identify the reproductive cycle phenotype in terms of intensity and duration of estrus. The study was conducted using Belmont Red (interbred Africander Brahman Hereford-Shorthorn) cattle grazing irrigated pasture on Belmont Research Station, northeastern Australia. The cow-bull associations from three groups of cows each with one bull were recorded over a 7-week breeding season and the stage of estrus was identified using ultrasonography. Telemetry data from bull and cows, collected over 4 8-day logger deployments, were log transformed and analyzed by ANOVA. Both the number and duration of bull-cow affiliations were significantly (P<0.001) greater in estrous cows compared to anestrus cows. These results support the development of the UHF technology as a hands-off and noninvasive means of gathering socio-sexual information on both wildlife and livestock for reproductive management. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.
Nutritional programming of reproductive development in heifers
USDA-ARS?s Scientific Manuscript database
Developmental programming is the biological process by which environmental factors influence the development of the organs and tissues in the body. There are two areas of developmental programming being investigated with applicability to beef production systems to improve performance of replacement...
Grollman, Christopher; Arregoces, Leonardo; Martínez-Álvarez, Melisa; Pitt, Catherine; Mills, Anne; Borghi, Josephine
2017-01-01
Tracking aid flows helps to hold donors accountable and to compare the allocation of resources in relation to health need. With the use of data reported by donors in 2015, we provided estimates of official development assistance and grants from the Bill & Melinda Gates Foundation (collectively termed ODA+) to reproductive, maternal, newborn, and child health for 2013 and complete trends in reproductive, maternal, newborn, and child health support for the period 2003-13. We coded and analysed financial disbursements to reproductive, maternal, newborn, and child health to all recipient countries from all donors reporting to the creditor reporting system database for the year 2013. We also revisited disbursement records for the years 2003-08 and coded disbursements relating to reproductive and sexual health activities resulting in the Countdown dataset for 2003-13. We matched this dataset to the 2015 creditor reporting system dataset and coded any unmatched creditor reporting system records. We analysed trends in ODA+ to reproductive, maternal, newborn, and child health for the period 2003-13, trends in donor contributions, disbursements to recipient countries, and targeting to need. Total ODA+ to reproductive, maternal, newborn, and child health reached nearly US$14 billion in 2013, of which 48% supported child health ($6·8 billion), 34% supported reproductive and sexual health ($4·7 billion), and 18% maternal and newborn health ($2·5 billion). ODA+ to reproductive, maternal, newborn, and child health increased by 225% in real terms over the period 2003-13. Child health received the most substantial increase in funding since 2003 (286%), followed by reproductive and sexual health (194%), and maternal and newborn health (164%). In 2013, bilateral donors disbursed 59% of all ODA+ to reproductive, maternal, newborn, and child health, followed by global health initiatives (23%), and multilateral agencies (13%). Targeting of ODA+ to reproductive, maternal, newborn, and child health to countries with the greatest health need seems to have improved over time. The increase in reproductive, maternal, newborn, and child health funding over the period 2003-13 is encouraging. Further increases in funding will be needed to accelerate maternal mortality reduction while keeping a high level of investment in sexual and reproductive health and in child health. Subgrant OPP1058954 from the US Fund for UNICEF under their Countdown to 2015 for Maternal, Newborn and Child Survival Grant from the Bill & Melinda Gates Foundation. Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.
Identification and assessment of endocrine disruptors: limitations of in vivo and in vitro assays.
Zacharewski, T
1998-01-01
It has been suggested that chemicals and complex mixtures capable of modulating the endocrine system may contribute to adverse health, reproduction, and developmental effects in humans and wildlife. These effects include increased incidence of hormone-dependent cancers, compromised reproductive fitness, and abnormal reproductive system development. In response to public concern, regulatory agencies in North America and Europe are formulating potential strategies to systematically test chemicals and complex mixtures for their endocrine-disrupting activities. Because of the complexity of the endocrine system and the number of potential endocrine disruptor targets, a tiered approach involving a complementary battery of short- and long-term in vivo and in vitro assays that assesses both receptor and nonreceptor-mediated mechanisms of action is being considered. However, the available established assays use a limited number of end points, and significant information gaps exist for other potential targets in the endocrine system. In addition to discussing the merits and limitations of the assays that may be adopted, this paper also highlights potential problems associated with the use of a tiered testing strategy. PMID:9599705
Effect of electromagnetic waves on human reproduction.
Wdowiak, Artur; Mazurek, Paweł A; Wdowiak, Anita; Bojar, Iwona
2017-03-31
Electromagnetic radiation (EMR) emitting from the natural environment, as well as from the use of industrial and everyday appliances, constantly influence the human body. The effect of this type of energy on living tissues may exert various effects on their functioning, although the mechanisms conditioning this phenomenon have not been fully explained. It may be expected that the interactions between electromagnetic radiation and the living organism would depend on the amount and parameters of the transmitted energy and type of tissue exposed. Electromagnetic waves exert an influence on human reproduction by affecting the male and female reproductive systems, the developing embryo, and subsequently, the foetus. Knowledge concerning this problem is still being expanded; however, all the conditionings of human reproduction still remain unknown. The study presents the current state of knowledge concerning the problem, based on the latest scientific reports.
Abrams, Elizabeth T; Miller, Elizabeth M
2011-01-01
Life history theory posits that, as long as survival is assured, finite resources are available for reproduction, maintenance, and growth/storage. To maximize lifetime reproductive success, resources are subject to trade-offs both within individuals and between current and future investment. For women, reproducing is costly and time-consuming; the bulk of available resources must be allocated to reproduction at the expense of more flexible systems like immune function. When reproducing women contract infectious diseases, the resources required for immune activation can fundamentally shift the patterns of resource allocation. Adding to the complexity of the reproductive-immune trade-offs in women are the pleiotropic effects of many immune factors, which were modified to serve key roles in mammalian reproduction. In this review, we explore the complex intersections between immune function and female reproduction to situate proximate immunological processes within a life history framework. After a brief overview of the immune system, we discuss some important physiological roles of immune factors in women's reproduction and the conflicts that may arise when these factors must play dual roles. We then discuss the influence of reproductive-immune trade-offs on the patterning of lifetime reproductive success: (1) the effect of immune activation/infectious disease on the timing of life history events; (2) the role of the immune system, immune activation, and infectious disease on resource allocation within individual reproductive events, particularly pregnancy; and (3) the role of the immune system in shaping the offspring's patterns of future life history trade-offs. We close with a discussion of future directions in reproductive immunology for anthropologists. Copyright © 2011 Wiley Periodicals, Inc.
Analysis of SI models with multiple interacting populations using subpopulations.
Thomas, Evelyn K; Gurski, Katharine F; Hoffman, Kathleen A
2015-02-01
Computing endemic equilibria and basic reproductive numbers for systems of differential equations describing epidemiological systems with multiple connections between subpopulations is often algebraically intractable. We present an alternative method which deconstructs the larger system into smaller subsystems and captures the interactions between the smaller systems as external forces using an approximate model. We bound the basic reproductive numbers of the full system in terms of the basic reproductive numbers of the smaller systems and use the alternate model to provide approximations for the endemic equilibrium. In addition to creating algebraically tractable reproductive numbers and endemic equilibria, we can demonstrate the influence of the interactions between subpopulations on the basic reproductive number of the full system. The focus of this paper is to provide analytical tools to help guide public health decisions with limited intervention resources.
The effects of kisspeptin in human reproductive function - therapeutic implications.
Ratnasabapathy, Risheka; Dhillo, Waljit S
2013-03-01
Kisspeptin is a 54-amino acid peptide which is encoded by the KiSS-1 gene and activates the G protein-coupled receptor GPR54. Evidence suggests that this system is a key regulator of mammalian and human reproduction. Animal studies have shown that GPR54-deficient mice have abnormal sexual development. Central and peripheral administration of kisspeptin stimulates the hypothalamic-pituitary-gonadal (HPG) axis whilst pre-administration of a gonadotrophin releasing hormone (GnRH) antagonist abolishes this effect. In humans, inactivating GPR54 mutations cause normosmic hypogonadotrophic hypogonadism whilst activation of GPR54 signalling is associated with premature puberty. In healthy human volunteers, the acute intravenous administration of kisspeptin potently increases plasma luteinising hormone (LH) levels and significantly increases plasma follicle stimulating hormone (FSH) and testosterone without side effects in both males and in females particularly in the preovulatatory phase of the menstrual cycle. In infertility due to hypothalamic amenorrhoea acute administration of kisspeptin results in stimulation of reproductive hormones. The kisspeptin/GPR54 system therefore appears to play an important role in the regulation of reproduction in humans. Hence kisspeptin has potential as a novel tool for the manipulation of the HPG axis and treatment of infertility in humans. This review discusses the evidence highlighting kisspeptin's key role in human reproduction.
Doe, J E
2014-10-01
There is an issue in the EU classification of substances for carcinogenicity and for reproductive or developmental toxicity which has brought difficulties to those involved in the process. The issue lies in the inability of the classification system to distinguish between carcinogens and reproductive toxicants with different levels of concern. This has its origins in the early years of toxicology when it was thought that a relatively small number of chemicals would be either carcinogens or reproductive toxicants, but this has turned out not to be the case. This can cause problems in communicating to the users of chemicals, including the public, the nature of the hazard presented by chemicals. Processes have been developed within the classification system for setting specific concentration limits which assess the degree of hazard for carcinogens and reproductive toxicants as high, medium or low. However these categories are not otherwise used in classification. It is proposed that their wider use would bring the advantages of transparency, clarity of communication, certainty of the process and would allow chemicals with a high degree of hazard to be identified and managed in an appropriate way. Copyright © 2014. The Authors. Journal of Applied Toxicology Published by John Wiley & Sons Ltd.
Background: Trends in male reproductive health have been reported for increased rates of testicular germ cell tumors, low semen quality, cryptorchidism, and hypospadias, which have been associated with prenatal environmental chemical exposure based on human and animal studies.Objective: In the present study we aimed to identify significant correlations between environmental chemicals, molecular targets, and adverse outcomes across a broad chemical landscape with emphasis on developmental toxicity of the male reproductive system.Methods: We used U.S. EPA??s animal study database (ToxRefDB) and a comprehensive literature analysis to identify 774 chemicals that have been evaluated for adverse effects on male reproductive parameters, and then used U.S. EPA??s in vitro high-throughput screening (HTS) database (ToxCastDB) to profile their bioactivity across approximately 800 molecular and cellular features. Results: A phenotypic hierarchy of testicular atrophy, sperm effects, tumors, and malformations, a composite resembling the human testicular dysgenesis syndrome (TDS) hypothesis, was observed in 281 chemicals. A subset of 54 chemicals with male developmental consequences had in vitro bioactivity on molecular targets that could be condensed into 156 gene annotations in a bipartite network. Conclusion: Computational modeling of available in vivo and in vitro data for chemicals that produce adverse effects on male reproductive end points revealed a phenotypic hierarch
Reproduction in the space environment: Part II. Concerns for human reproduction
NASA Technical Reports Server (NTRS)
Jennings, R. T.; Santy, P. A.
1990-01-01
Long-duration space flight and eventual colonization of our solar system will require successful control of reproductive function and a thorough understanding of factors unique to space flight and their impact on gynecologic and obstetric parameters. Part II of this paper examines the specific environmental factors associated with space flight and the implications for human reproduction. Space environmental hazards discussed include radiation, alteration in atmospheric pressure and breathing gas partial pressures, prolonged toxicological exposure, and microgravity. The effects of countermeasures necessary to reduce cardiovascular deconditioning, calcium loss, muscle wasting, and neurovestibular problems are also considered. In addition, the impact of microgravity on male fertility and gamete quality is explored. Due to current constraints, human pregnancy is now contraindicated for space flight. However, a program to explore effective countermeasures to current constraints and develop the required health care delivery capability for extended-duration space flight is suggested. A program of Earth- and space-based research to provide further answers to reproductive questions is suggested.
[Human reproduction and environmental risk factors].
Petrelli, G; Mantovani, A; Menditto, A
1999-01-01
Environmental pollution is a great cause of concern, in particular, growing attention is being paid to the potential of many chemicals to affect the reproductive system in humans. The key role of prevention and control of reproductive hazards is recognized world-wide. Many chemicals have been shown to impair fertility and/or prenatal and perinatal development in experimental studies. However, a sufficient evidence of an effect on human reproduction is available for some compounds only. The use of biological markers may improve the assessment of exposure to chemicals, contribute to identify mechanisms of action and put into evidence early, reversible, biological effects. Valid biological markers are also needed in epidemiological studies: without reliable data on the level of current and past exposures it is difficult to establish a causal relationship between a pollutant and the occurrence of adverse health effects. A multidisciplinary approach to risk assessment is required. Priorities for interdisciplinary research on environmental chemicals and reproduction include the identification of susceptible population subgroups and risk assessment of exposure to multiple chemicals.
Parham, Peter; Moffett, Ashley
2013-02-01
Natural killer (NK) cells have roles in immunity and reproduction that are controlled by variable receptors that recognize MHC class I molecules. The variable NK cell receptors found in humans are specific to simian primates, in which they have progressively co-evolved with MHC class I molecules. The emergence of the MHC-C gene in hominids drove the evolution of a system of NK cell receptors for MHC-C molecules that is most elaborate in chimpanzees. By contrast, the human system of MHC-C receptors seems to have been subject to different selection pressures that have acted in competition on the immunological and reproductive functions of MHC class I molecules. We suggest that this compromise facilitated the development of the bigger brains that enabled archaic and modern humans to migrate out of Africa and populate other continents.
Jung, Seok-Won; Kim, Hyeon-Joong; Lee, Byung-Hwan; Choi, Sun-Hye; Kim, Hyun-Sook; Choi, Yang-Kyu; Kim, Joon Yong; Kim, Eun-Soo; Hwang, Sung-Hee; Lim, Kwang Yong; Kim, Hyoung-Chun; Jang, Minhee; Park, Seong Kyu; Cho, Ik-Hyun; Nah, Seung-Yeol
2015-07-01
Anticancer agents induce a variety of adverse effects when administered to cancer patients. Busulfan is a known antileukemia agent. When administered for treatment of leukemia in young patients, busulfan could cause damage to the male reproductive system as one of its adverse effects, resulting in sterility. We investigated the effects of Korean Red Ginseng extract (KRGE) on busulfan-induced damage and/or dysfunction of the male reproductive system. We found that administration of busulfan to mice: decreased testis weight; caused testicular histological damage; reduced the total number of sperm, sperm motility, serum testosterone concentration; and eventually, litter size. Preadministration of KRGE partially attenuated various busulfan-induced damages to the male reproductive system. These results indicate that KRGE has a protective effect against busulfan-induced damage to the male reproduction system. The present study shows a possibility that KRGE could be applied as a useful agent to prevent or protect the male reproductive system from the adverse side effects induced by administration of anticancer agents such as busulfan.
Mageroy, Jon H; Grepperud, Eldfrid J; Jensen, Knut Helge
2011-12-01
We investigated whether parasites or hosts benefit from reduced reproduction in infected hosts. When parasites castrate their hosts, the regain of host reproduction is necessary for castration to be a host adaptation. When infecting Daphnia magna with Pasteuria ramosa, in a lake water based medium, 49 2% of the castrated females regained reproduction. We investigated the relationship between castration level, and parasite and host fitness proxies to determine the adaptive value of host castration. Hosts which regained reproduction contained less spores and had a higher lifetime reproduction than permanently castrated hosts. We also found a negative correlation between parasite and host lifetime reproduction. For hosts which regained reproduction we found no optimal level of castration associated with lifetime reproduction. These results support the view that host castration only is adaptive to the parasite in this system. In addition, we suggest that permanent castration might not be the norm under natural conditions in this system. Finally, we argue that a reduction in host reproduction is more likely to evolve as a property favouring parasites rather than hosts. To our knowledge this is the only experimental study to investigate the adaptive value of reduced host reproduction when castrated hosts can regain reproduction.
Minelli, Alessandro
2016-09-01
Descriptions and interpretations of the natural world are dominated by dichotomies such as organism vs. environment, nature vs. nurture, genetic vs. epigenetic, but in the last couple of decades strong dissatisfaction with those partitions has been repeatedly voiced and a number of alternative perspectives have been suggested, from perspectives such as Dawkins' extended phenotype, Turner's extended organism, Oyama's Developmental Systems Theory and Odling-Smee's niche construction theory. Last in time is the description of biological phenomena in terms of hybrids between an organism (scaffolded system) and a living or non-living scaffold, forming unit systems to study processes such as reproduction and development. As scaffold, eventually, we can define any resource used by the biological system, especially in development and reproduction, without incorporating it as happens in the case of resources fueling metabolism. Addressing biological systems as functionally scaffolded systems may help pointing to functional relationships that can impart temporal marking to the developmental process and thus explain its irreversibility; revisiting the boundary between development and metabolism and also regeneration phenomena, by suggesting a conceptual framework within which to investigate phenomena of regular hypermorphic regeneration such as characteristic of deer antlers; fixing a periodization of development in terms of the times at which a scaffolding relationship begins or is terminated; and promoting plant galls to legitimate study objects of developmental biology.
microRNA in Human Reproduction.
Eisenberg, Iris; Kotaja, Noora; Goldman-Wohl, Debra; Imbar, Tal
2015-01-01
microRNAs constitute a large family of approximately 21-nucleotide-long, noncoding RNAs. They emerged more than 20 years ago as key posttranscriptional regulators of gene expression. The regulatory role of these small RNA molecules has recently begun to be explored in the human reproductive system. microRNAs have been shown to play an important role in control of reproductive functions, especially in the processes of oocyte maturation, folliculogenesis, corpus luteum function, implantation, and early embryonic development. Knockout of Dicer, the cytoplasmic enzyme that cleaves the pre-miRNA to its mature form, results in postimplantation embryonic lethality in several animal models, attributing to these small RNA vital functions in reproduction and development. Another intriguing characteristic of microRNAs is their presence in body fluids in a remarkably stable form that is protected from endogenous RNase activity. In this chapter we will describe the current knowledge on microRNAs, specifically relating to human gonadal cells. We will focus on their role in the ovarian physiologic process and ovulation dysfunction, regulation of spermatogenesis and male fertility, and putative involvement in human normal and aberrant trophoblast differentiation and invasion through the process of placentation.
Fractional parentage analysis and a scale-free reproductive network of brown trout.
Koyano, Hitoshi; Serbezov, Dimitar; Kishino, Hirohisa; Schweder, Tore
2013-11-07
In this study, we developed a method of fractional parentage analysis using microsatellite markers. We propose a method for calculating parentage probability, which considers missing data and genotyping errors due to null alleles and other causes, by regarding observed alleles as realizations of random variables which take values in the set of alleles at the locus and developing a method for simultaneously estimating the true and null allele frequencies of all alleles at each locus. We then applied our proposed method to a large sample collected from a wild population of brown trout (Salmo trutta). On analyzing the data using our method, we found that the reproductive success of brown trout obeyed a power law, indicating that when the parent-offspring relationship is regarded as a link, the reproductive system of brown trout is a scale-free network. Characteristics of the reproductive network of brown trout include individuals with large bodies as hubs in the network and different power exponents of degree distributions between males and females. © 2013 Elsevier Ltd. All rights reserved.
de Ziegler, Dominique; de Ziegler, Nathalie; Sean, Sokteang; Bajouh, Osama; Meldrum, David R
2015-07-01
Standardized, high-quality training in reproductive endocrinology, infertility, and assisted reproductive technologies (REI-ART) faces challenges owing to the high-tech nature of ART and the important country-to-country differences in clinical practice and regulations overseeing training. Moreover, while the training capacity of the classical by-fellowship training platforms is shrinking, an increasing demand for REI-ART specialists is coming from emerging countries. To meet this expanding need for REI-ART specialists, we propose a novel by-network model linking a reference training center to satellite practical training sites. Simulation should be used more extensively to achieve competency before initiating live clinical experience, analogous to the highly effective training systems that have been used in aviation for decades. Large ART databases that exist because of obligations to report ART activity and results constitute unique yet so far untapped sources for developing by-scenario simulation training models. Online training materials incorporating these state-of-the-art information technology tools could be developed as a means of fulfilling training needs worldwide. Copyright © 2015. Published by Elsevier Inc.
Chemosignals, Hormones and Mammalian Reproduction
Petrulis, Aras
2013-01-01
Many mammalian species use chemosignals to coordinate reproduction by altering the physiology and behavior of both sexes. Chemosignals prime reproductive physiology so that individuals become sexually mature and active at times when mating is most probable and suppress it when it is not. Once in reproductive condition, odors produced and deposited by both males and females are used to find and select individuals for mating. The production, dissemination and appropriate responses to these cues are modulated heavily by organizational and activational effects of gonadal sex steroids and thereby intrinsically link chemical communication to the broader reproductive context. Many compounds have been identified as “pheromones” but very few have met the expectations of that term: a unitary, species-typical substance that is both necessary and sufficient for an experience-independent behavioral or physiological response. In contrast, most responses to chemosignals are dependent or heavily modulated by experience, either in adulthood or during development. Mechanistically, chemosignals are perceived by both main and accessory (vomeronasal) olfactory systems with the importance of each system tied strongly to the nature of the stimulus rather than to the response. In the central nervous system, the vast majority of responses to chemosignals are mediated by cortical and medial amygdala connections with hypothalamic and other forebrain structures. Despite the importance of chemosignals in mammals, many details of chemical communication differ even among closely related species and defy clear categorization. Although generating much research and public interest, strong evidence for the existence of a robust chemical communication among humans is lacking. PMID:23545474
Robo1/2 regulate follicle atresia through manipulating granulosa cell apoptosis in mice
Li, Jiangchao; Ye, Yuxiang; Zhang, Renli; Zhang, Lili; Hu, Xiwen; Han, Dong; Chen, Jiayuan; He, Xiaodong; Wang, Guang; Yang, Xuesong; Wang, Lijing
2015-01-01
Secreted Slit proteins and their Roundabout (Robo) receptors act as a repulsive cue to preventaxons from migrating to inappropriate locations during the development of the nervous system. Slit/Robo has also been implicated in reproductive system development, but the molecular mechanism of the Slit/Robo pathway in the reproductive system remains poorly understood. Using a transgenic mouse model, we investigated the function of the Slit/Robo pathway on ovarian follicle development and atresia. We first demonstrated that more offspring were born to mice with a partial knockout of the Robo1/2 genes in mice. We next showed that Robo1 and Robo2 are strongly expressed in ovarian granulosacells. Apoptosis in granulosa cells was reduced when Robo1/2 were partially knocked out, and this observation was further verified by in vitro Robo1/2 knockout experiments in mouse and human granulosa cells. We also found that ovarian angiogenesis wasenhanced by a partial lack of Robo1/2 genes. In summary, our data suggest that the Slit/Robo pathway can impact follicle development and atresia by influencinggranulosa cell apoptosis. PMID:25988316
Clarke, D O; Hilbish, K G; Waters, D G; Newcomb, D L; Chellman, G J
2015-12-01
The reproductive and developmental toxicity of ixekizumab, a selective inhibitor of interleukin-17A (IL-17A), was assessed in the following studies in cynomolgus monkeys: fertility (3-month dosing), embryo-fetal development (EFD; dosing from gestation day (GD) 20 through 139), and pre-postnatal development (PPND; dosing from GD 20 through parturition). Because IL-17A has functional roles in innate and humoral immunity, immune system modulation was evaluated in the EFD and PPND studies; immunological evaluations in infants comprised peripheral blood immunophenotyping, Natural Killer cell cytolytic activity, and T-cell-dependent antibody (IgG and IgM) primary and secondary responses to antigen challenge. Ixekizumab exposure was sustained during the dosing periods in most adult monkeys. Fetal exposure at Cesarean section (GD 140-142; EFD study) was 18-25% of maternal exposure and ixekizumab was present in infants for up to 29 weeks postpartum. There were no adverse effects attributed to ixekizumab in any study. Importantly, immune system development and maturation were unaffected. Copyright © 2015 Elsevier Inc. All rights reserved.
Transgenic Reproductive Cell Ablation.
Lawit, Shai J; Chamberlin, Mark A
2017-01-01
Numerous cell ablation technologies are available and have been used in reproductive tissues, particularly for male tissues and cells. The importance of ablation of reproductive tissues is toward a fundamental understanding reproductive tissue development and fertilization, as well as, in developing sterility lines important to breeding strategies. Here, we describe techniques for developing ablation lines for both male and female reproductive cells. Also discussed are techniques for analysis, quality control, maintenance, and the lessening of pleiotropism in such lines.
Neethling, Lourelle Alicia Martins; Avenant-Oldewage, Annemariè
2015-02-01
The morphology of the male reproductive system as well as sperm transfer in Branchiura has been described for Dolops ranarum and Argulus japonicus. In this study, the reproductive system and accessory structures are described for male Chonopeltis australis using histology, light microscopy, and scanning electron microscopy. For the first time, we describe sperm transfer by means of a spermatophore in this genus. The internal and external morphology and mechanism of sperm transfer is compared with other Branchiura, where it has been described. The morphology of the reproductive system of C. australis is similar to that of D. ranarum while the accessory structures and the spermatophore produced are similar to that of A. japonicus. A revision of the definition of Branchiura with respect to reproduction is provided. © 2014 Wiley Periodicals, Inc.
Fujii, Junichi; Iuchi, Yoshihito; Okada, Futoshi
2005-09-02
Controlled oxidation, such as disulfide bond formation in sperm nuclei and during ovulation, plays a fundamental role in mammalian reproduction. Excess oxidation, however, causes oxidative stress, resulting in the dysfunction of the reproductive process. Antioxidation reactions that reduce the levels of reactive oxygen species are of prime importance in reproductive systems in maintaining the quality of gametes and support reproduction. While anti-oxidative enzymes, such as superoxide dismutase and peroxidase, play a central role in eliminating oxidative stress, reduction-oxidation (redox) systems, comprised of mainly glutathione and thioredoxin, function to reduce the levels of oxidized molecules. Aldo-keto reductase, using NADPH as an electron donor, detoxifies carbonyl compounds resulting from the oxidation of lipids and proteins. Thus, many antioxidative and redox enzyme genes are expressed and aggressively protect gametes and embryos in reproductive systems.
NASA Astrophysics Data System (ADS)
Miyakawa, Misato O.; Mikheyev, Alexander S.
2015-04-01
Evolution of reproduction strategies is affected by both phylogenetic and physiological constraints. Although clonality may benefit females, it may not be selected if a male contribution is necessary to start egg laying and embryo development. In little fire ant, Wasmannia auropunctata, sexual populations employ a typical Hymenopteran system of reproduction. In clonal populations, however, queens and males are produced with only maternal and paternal genomes, respectively, whereas sterile workers are produced sexually. Although this system requires both sexes for worker production, previous work has shown that workers may also be produced clonally by the queens. If so, why are males maintained in this species? Our data suggest that fertilization is necessary to increase the hatching rate of eggs. Although clonal queens can indeed produce both workers and queens without mating, the hatching rate is far below the level necessary to maintain functional colonies. On the other hand, virgin queens from populations exhibiting the original Hymenopteran reproduction system also show low hatching rates, but produce only haploid male eggs. Reasons for the existence of W. auropunctata males have been disputed. However, our data suggest that physiological constraints, such as the requirement for insemination, must be considered in regard to evolution of reproduction systems, in addition to ecological data and theoretical considerations of fitness.
FMRFamide-like peptides expand the behavioral repertoire of a densely connected nervous system
Schaedel, Oren N.; Rogers, Alicia K.
2017-01-01
Animals, including humans, can adapt to environmental stress through phenotypic plasticity. The free-living nematode Caenorhabditis elegans can adapt to harsh environments by undergoing a whole-animal change, involving exiting reproductive development and entering the stress-resistant dauer larval stage. The dauer is a dispersal stage with dauer-specific behaviors for finding and stowing onto carrier animals, but how dauers acquire these behaviors, despite having a physically limited nervous system of 302 neurons, is poorly understood. We compared dauer and reproductive development using whole-animal RNA sequencing at fine time points and at sufficient depth to measure transcriptional changes within single cells. We detected 8,042 genes differentially expressed during dauer and reproductive development and observed striking up-regulation of neuropeptide genes during dauer entry. We knocked down neuropeptide processing using sbt-1 mutants and demonstrate that neuropeptide signaling promotes the decision to enter dauer rather than reproductive development. We also demonstrate that during dauer neuropeptides modulate the dauer-specific nictation behavior (carrier animal-hitchhiking) and are necessary for switching from repulsion to CO2 (a carrier animal cue) in nondauers to CO2 attraction in dauers. We tested individual neuropeptides using CRISPR knockouts and existing strains and demonstrate that the combined effects of flp-10 and flp-17 mimic the effects of sbt-1 on nictation and CO2 attraction. Through meta-analysis, we discovered similar up-regulation of neuropeptides in the dauer-like infective juveniles of diverse parasitic nematodes, suggesting the antiparasitic target potential of SBT-1. Our findings reveal that, under stress, increased neuropeptide signaling in C. elegans enhances their decision-making accuracy and expands their behavioral repertoire. PMID:29167374
Pallarés, María Eugenia; Adrover, Ezequiela; Baier, Carlos Javier; Bourguignon, Nadia S; Monteleone, Melisa C; Brocco, Marcela A; González-Calvar, Silvia I; Antonelli, Marta C
2013-07-01
Several studies have demonstrated that the presence of stressors during pregnancy induces adverse effects on the neuroendocrine system of the offspring later in life. In the present work, we investigated the effects of early programming on the male reproductive system, employing a prenatal stress (PS) paradigm. This study found that when pregnant dams were placed in a plastic restrainer three times a day during the last week of pregnancy, the offspring showed reduced anogenital distance and delayed testicular descent. Serum luteinising hormone (LH) and follicle-stimulating hormone (FSH) levels were decreased at postnatal day (PND) 28 and testosterone was decreased at PND 75. Increased testosterone plus dihydrotestosterone (T + DHT) concentrations correlated with increased testicular 5α Reductase-1 (5αR-1) mRNA expression at PND 28. Moreover, PS accelerated spermatogenesis at PND 35 and 60, and increased mean seminiferous tubule diameter in pubertal offspring and reduced Leydig cell number was observed at PND 35 and 60. PS offspring had increased androgen receptor (AR) mRNA level at PND 28, and at PND 35 had increased the numbers of Sertoli cells immunopositive for AR. Overall, the results confirm that stress during gestation can induce long-term effects on the male offspring reproductive system. Of particular interest is the pre-pubertal imbalance of circulating hormones that probably trigger accelerated testicular development, followed by an increase in total androgens and a decrease in testosterone concentration during adulthood. Exposure to an unfavourable intrauterine environment might prepare for harsh external conditions by triggering early puberty, increasing reproductive potential.
Impact of reproductive health on socio-economic development: a case study of Nigeria.
Adinma, J I B; Adinma, E D
2011-03-01
The link between reproductive health, sexual and reproductive right, and development was highlighted at the International Conference on Population and Development held in Egypt. Developmental disparities are related to socio-economic differences which have led to the identification of distinct socio-economic classifications of nations. Human development represents the socioeconomic standing of any nation, in addition to literacy status and life expectancy. Africa accounts for 25% of the world's landmass but remains the world's poorest continent. Nigeria, the most populous country in Africa, has policies and programmes geared towards the improvement of its socio-economic standing and overal development, with little positive result. Reproductive health is a panacea towards reversing the stalled socio-economic growth of Nigeria as evident from the linkage between reproductive health and development, highlighted in Millennium Development Goals 3, 4, 5 and 6. Fast tracking Nigeria's development requires implementation of reproductive health policies and programmes targeted on women and children.
Endocrine-disrupting chemicals-Mechanisms of action on male reproductive system.
Sidorkiewicz, Iwona; Zaręba, Kamil; Wołczyński, Sławomir; Czerniecki, Jan
2017-07-01
Endocrine-disrupting chemicals (EDCs) are exogenous compounds that can cause disturbances in the endocrine system and have multiple harmful effects on health by targeting different organs and systems in the human body. Mass industrial production and widespread use of EDCs have resulted in worldwide contamination. Accumulating evidence suggest that human exposure to EDCs is related to the impairment of male reproductive function and can interrupt other hormonally regulated metabolic processes, particularly if exposure occurs during early development. Investigation of studies absent in previous reviews and meta-analysis of adverse effects of EDCs on functioning of the male reproductive system is the core of this work. Four main modes of action of EDCs on male fertility have been summarized in this review. First, studies describing estrogen- pathway disturbing chemicals are investigated. Second, androgen-signaling pathway alterations and influence on androgen sensitive tissues are examined. Third, evaluation of steroidogenesis dysfunction is discussed by focusing on the steroid hormone biosynthesis pathway, which is targeted by EDCs. Last, the reportedly destructive role of reactive oxygen species (ROS) on sperm function is discussed. Spermatogenesis is a remarkably complex process, hence multiple studies point out various dysfunctions depending on the development state at which the exposure occurred. Collected data show the need to account for critical windows of exposure such as fetal, perinatal and pubertal periods as well as effects of mixtures of several compounds in future research.
Effects of environmental pollutants on the reproduction and welfare of ruminants
Rhind, S. M.; Evans, N. P.; Bellingham, M.; Sharpe, R. M.; Cotinot, C.; Mandon-Pepin, B.; Loup, B.; Sinclair, K. D.; Lea, R. G.; Pocar, P.; Fischer, B.; van der Zalm, E.; Hart, K.; Schmidt, J.-S.; Amezaga, M. R.; Fowler, P. A.
2010-01-01
Anthropogenic pollutants comprise a wide range of synthetic organic compounds and heavy metals, which are dispersed throughout the environment, usually at low concentrations. Exposure of ruminants, as for all other animals, is unavoidable and while the levels of exposure to most chemicals are usually too low to induce any physiological effects, combinations of pollutants can act additively or synergistically to perturb multiple physiological systems at all ages but particularly in the developing foetus. In sheep, organs affected by pollutant exposure include the ovary, testis, hypothalamus and pituitary gland and bone. Reported effects of exposure include changes in organ weight and gross structure, histology and gene and protein expression but these changes are not reflected in changes in reproductive performance under the conditions tested. These results illustrate the complexity of the effects of endocrine disrupting compounds on the reproductive axis, which make it difficult to extrapolate between, or even within, species. Effects of pollutant exposure on the thyroid gland, immune, cardiovascular and obesogenic systems have not been shown explicitly, in ruminants, but work on other species suggests that these systems can also be perturbed. It is concluded that exposure to a mixture of anthropogenic pollutants has significant effects on a wide variety of physiological systems, including the reproductive system. Although this physiological insult has not yet been shown to lead to a reduction in ruminant gross performance, there are already reports indicating that anthropogenic pollutant exposure can compromise several physiological systems and may pose a significant threat to both reproductive performance and welfare in the longer term. At present, many potential mechanisms of action for individual chemicals have been identified but knowledge of factors affecting the rate of tissue exposure and of the effects of combinations of chemicals on physiological systems is poor. Nevertheless, both are vital for the identification of risks to animal productivity and welfare. PMID:20582145
NASA Astrophysics Data System (ADS)
Huang, Qingyu; Luo, Lianzhong; Alamdar, Ambreen; Zhang, Jie; Liu, Liangpo; Tian, Meiping; Eqani, Syed Ali Musstjab Akber Shah; Shen, Heqing
2016-09-01
Arsenic is a widespread metalloid in environment, whose exposure has been associated with a broad spectrum of toxic effects. However, a global view of arsenic-induced male reproductive toxicity is still lack, and the underlying mechanisms remain largely unclear. Our results revealed that arsenic exposure decreased testosterone level and reduced sperm quality in rats. By conducting an integrated proteomics and metabolomics analysis, the present study aims to investigate the global influence of arsenic exposure on the proteome and metabolome in rat testis. The abundance of 70 proteins (36 up-regulated and 34 down-regulated) and 13 metabolites (8 increased and 5 decreased) were found to be significantly altered by arsenic treatment. Among these, 19 proteins and 2 metabolites were specifically related to male reproductive system development and function, including spermatogenesis, sperm function and fertilization, fertility, internal genitalia development, and mating behavior. It is further proposed that arsenic mainly impaired spermatogenesis and fertilization via aberrant modulation of these male reproduction-related proteins and metabolites, which may be mediated by the ERK/AKT/NF-κB-dependent signaling pathway. Overall, these findings will aid our understanding of the mechanisms responsible for arsenic-induced male reproductive toxicity, and from such studies useful biomarkers indicative of arsenic exposure could be discovered.
Huang, Qingyu; Luo, Lianzhong; Alamdar, Ambreen; Zhang, Jie; Liu, Liangpo; Tian, Meiping; Eqani, Syed Ali Musstjab Akber Shah; Shen, Heqing
2016-09-02
Arsenic is a widespread metalloid in environment, whose exposure has been associated with a broad spectrum of toxic effects. However, a global view of arsenic-induced male reproductive toxicity is still lack, and the underlying mechanisms remain largely unclear. Our results revealed that arsenic exposure decreased testosterone level and reduced sperm quality in rats. By conducting an integrated proteomics and metabolomics analysis, the present study aims to investigate the global influence of arsenic exposure on the proteome and metabolome in rat testis. The abundance of 70 proteins (36 up-regulated and 34 down-regulated) and 13 metabolites (8 increased and 5 decreased) were found to be significantly altered by arsenic treatment. Among these, 19 proteins and 2 metabolites were specifically related to male reproductive system development and function, including spermatogenesis, sperm function and fertilization, fertility, internal genitalia development, and mating behavior. It is further proposed that arsenic mainly impaired spermatogenesis and fertilization via aberrant modulation of these male reproduction-related proteins and metabolites, which may be mediated by the ERK/AKT/NF-κB-dependent signaling pathway. Overall, these findings will aid our understanding of the mechanisms responsible for arsenic-induced male reproductive toxicity, and from such studies useful biomarkers indicative of arsenic exposure could be discovered.
Many environmental contaminants have the potential to disrupt endocrine systems of wildlife and humans resulting in impairment of reproductive and other systems. A subset of these contaminants may initiate these effects by binding to the estrogen receptor. In oviparous vertebrate...
Multiscale Systems Modeling of Male Reproductive Tract ...
The reproductive tract is a complex, integrated organ system with diverse embryology and unique sensitivity to prenatal environmental exposures that disrupt morphoregulatory processes and endocrine signaling. U.S. EPA’s in vitro high-throughput screening (HTS) database (ToxCastDB) was used to profile the bioactivity of 54 chemicals with male developmental consequences across ~800 molecular and cellular features [Leung et al., accepted manuscript]. The in vitro bioactivity on molecular targets could be condensed into 156 gene annotations in a bipartite network. These results highlighted the role of estrogen and androgen signaling pathways in male reproductive tract development, and importantly, broadened the list of molecular targets to include GPCRs, cytochrome-P450s, vascular remodeling proteins, and retinoic acid signaling. A multicellular agent-based model was used to simulate the complex interactions between morphoregulatory, endocrine, and environmental influences during genital tubercle (GT) development. Spatially dynamic signals (e.g., SHH, FGF10, and androgen) were implemented in the model to address differential adhesion, cell motility, proliferation, and apoptosis. Urethral tube closure was an emergent feature of the model that was linked to gender-specific rates of ventral mesenchymal proliferation and urethral plate endodermal apoptosis, both under control of androgen signaling [Leung et al., manuscript in preparation]. A systemic parameter sweep w
Cross-Generational Reproductive Fitness Enforced by Microchimeric Maternal Cells.
Kinder, Jeremy M; Jiang, Tony T; Ertelt, James M; Xin, Lijun; Strong, Beverly S; Shaaban, Aimen F; Way, Sing Sing
2015-07-30
Exposure to maternal tissue during in utero development imprints tolerance to immunologically foreign non-inherited maternal antigens (NIMA) that persists into adulthood. The biological advantage of this tolerance, conserved across mammalian species, remains unclear. Here, we show maternal cells that establish microchimerism in female offspring during development promote systemic accumulation of immune suppressive regulatory T cells (Tregs) with NIMA specificity. NIMA-specific Tregs expand during pregnancies sired by males expressing alloantigens with overlapping NIMA specificity, thereby averting fetal wastage triggered by prenatal infection and non-infectious disruptions of fetal tolerance. Therefore, exposure to NIMA selectively enhances reproductive success in second-generation females carrying embryos with overlapping paternally inherited antigens. These findings demonstrate that genetic fitness, canonically thought to be restricted to Mendelian inheritance, is enhanced in female placental mammals through vertically transferred maternal cells that promote conservation of NIMA and enforce cross-generational reproductive benefits. Copyright © 2015 Elsevier Inc. All rights reserved.
Development of a directivity-controlled piezoelectric transducer for sound reproduction
NASA Astrophysics Data System (ADS)
Bédard, Magella; Berry, Alain
2008-04-01
Present sound reproduction systems do not attempt to simulate the spatial radiation of musical instruments, or sound sources in general, even though the spatial directivity has a strong impact on the psychoacoustic experience. A transducer consisting of 4 piezoelectric elemental sources made from curved PVDF films is used to generate a target directivity pattern in the horizontal plane, in the frequency range of 5-20 kHz. The vibratory and acoustical response of an elemental source is addressed, both theoretically and experimentally. Two approaches to synthesize the input signals to apply to each elemental source are developed in order to create a prescribed, frequency-dependent acoustic directivity. The circumferential Fourier decomposition of the target directivity provides a compromise between the magnitude and the phase reconstruction, whereas the minimization of a quadratic error criterion provides a best magnitude reconstruction. This transducer can improve sound reproduction by introducing the spatial radiation aspect of the original source at high frequency.
Caste development and reproduction: a genome-wide analysis of hallmarks of insect eusociality
Cristino, A S; Nunes, F M F; Lobo, C H; Bitondi, M M G; Simões, Z L P; Da Fontoura Costa, L; Lattorff, H M G; Moritz, R F A; Evans, J D; Hartfelder, K
2006-01-01
The honey bee queen and worker castes are a model system for developmental plasticity. We used established expressed sequence tag information for a Gene Ontology based annotation of genes that are differentially expressed during caste development. Metabolic regulation emerged as a major theme, with a caste-specific difference in the expression of oxidoreductases vs. hydrolases. Motif searches in upstream regions revealed group-specific motifs, providing an entry point to cis-regulatory network studies on caste genes. For genes putatively involved in reproduction, meiosis-associated factors came out as highly conserved, whereas some determinants of embryonic axes either do not have clear orthologs (bag of marbles, gurken, torso), or appear to be lacking (trunk) in the bee genome. Our results are the outcome of a first genome-based initiative to provide an annotated framework for trends in gene regulation during female caste differentiation (representing developmental plasticity) and reproduction. PMID:17069641
Pask, Andrew
2016-01-01
Correct sexual development is arguably the most important trait in an organism's life history since it is directly related to its genetic fitness. The developing gonad houses the germ cells, the only legacy we pass on to subsequent generations. Given the pivotal importance of correct reproductive function, it is confounding that disorders of sex development (DSDs) are among the most common congenital abnormalities in humans (Lee et al. J Pediatr Urol 8(6):611-615, 2012). Urogenital development is a highly complex process involving coordinated interactions between molecular and hormonal pathways in a tightly regulated order. The controls that regulate some of the key events in this process are beginning to be unraveled. This chapter provides an overview of our understanding of urogenital development from the gonads to the urogenital ducts and external genitalia.
2011-01-01
Background We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. Results The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. Conclusions Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution. PMID:21854559
Renfree, Marilyn B; Papenfuss, Anthony T; Deakin, Janine E; Lindsay, James; Heider, Thomas; Belov, Katherine; Rens, Willem; Waters, Paul D; Pharo, Elizabeth A; Shaw, Geoff; Wong, Emily S W; Lefèvre, Christophe M; Nicholas, Kevin R; Kuroki, Yoko; Wakefield, Matthew J; Zenger, Kyall R; Wang, Chenwei; Ferguson-Smith, Malcolm; Nicholas, Frank W; Hickford, Danielle; Yu, Hongshi; Short, Kirsty R; Siddle, Hannah V; Frankenberg, Stephen R; Chew, Keng Yih; Menzies, Brandon R; Stringer, Jessica M; Suzuki, Shunsuke; Hore, Timothy A; Delbridge, Margaret L; Patel, Hardip R; Mohammadi, Amir; Schneider, Nanette Y; Hu, Yanqiu; O'Hara, William; Al Nadaf, Shafagh; Wu, Chen; Feng, Zhi-Ping; Cocks, Benjamin G; Wang, Jianghui; Flicek, Paul; Searle, Stephen M J; Fairley, Susan; Beal, Kathryn; Herrero, Javier; Carone, Dawn M; Suzuki, Yutaka; Sugano, Sumio; Toyoda, Atsushi; Sakaki, Yoshiyuki; Kondo, Shinji; Nishida, Yuichiro; Tatsumoto, Shoji; Mandiou, Ion; Hsu, Arthur; McColl, Kaighin A; Lansdell, Benjamin; Weinstock, George; Kuczek, Elizabeth; McGrath, Annette; Wilson, Peter; Men, Artem; Hazar-Rethinam, Mehlika; Hall, Allison; Davis, John; Wood, David; Williams, Sarah; Sundaravadanam, Yogi; Muzny, Donna M; Jhangiani, Shalini N; Lewis, Lora R; Morgan, Margaret B; Okwuonu, Geoffrey O; Ruiz, San Juana; Santibanez, Jireh; Nazareth, Lynne; Cree, Andrew; Fowler, Gerald; Kovar, Christie L; Dinh, Huyen H; Joshi, Vandita; Jing, Chyn; Lara, Fremiet; Thornton, Rebecca; Chen, Lei; Deng, Jixin; Liu, Yue; Shen, Joshua Y; Song, Xing-Zhi; Edson, Janette; Troon, Carmen; Thomas, Daniel; Stephens, Amber; Yapa, Lankesha; Levchenko, Tanya; Gibbs, Richard A; Cooper, Desmond W; Speed, Terence P; Fujiyama, Asao; Graves, Jennifer A M; O'Neill, Rachel J; Pask, Andrew J; Forrest, Susan M; Worley, Kim C
2011-08-29
We present the genome sequence of the tammar wallaby, Macropus eugenii, which is a member of the kangaroo family and the first representative of the iconic hopping mammals that symbolize Australia to be sequenced. The tammar has many unusual biological characteristics, including the longest period of embryonic diapause of any mammal, extremely synchronized seasonal breeding and prolonged and sophisticated lactation within a well-defined pouch. Like other marsupials, it gives birth to highly altricial young, and has a small number of very large chromosomes, making it a valuable model for genomics, reproduction and development. The genome has been sequenced to 2 × coverage using Sanger sequencing, enhanced with additional next generation sequencing and the integration of extensive physical and linkage maps to build the genome assembly. We also sequenced the tammar transcriptome across many tissues and developmental time points. Our analyses of these data shed light on mammalian reproduction, development and genome evolution: there is innovation in reproductive and lactational genes, rapid evolution of germ cell genes, and incomplete, locus-specific X inactivation. We also observe novel retrotransposons and a highly rearranged major histocompatibility complex, with many class I genes located outside the complex. Novel microRNAs in the tammar HOX clusters uncover new potential mammalian HOX regulatory elements. Analyses of these resources enhance our understanding of marsupial gene evolution, identify marsupial-specific conserved non-coding elements and critical genes across a range of biological systems, including reproduction, development and immunity, and provide new insight into marsupial and mammalian biology and genome evolution.
Vitamins are substances that your body needs to grow and develop normally. Vitamin A plays a role in your Vision Bone growth Reproduction Cell functions Immune system Vitamin A is an antioxidant. It can come from ...
Chalivendra, Subbaiah C.; Lopez-Casado, Gloria; Bedinger, Patricia A.
2013-01-01
Although self-incompatibility (SI) in plants has been studied extensively, far less is known about interspecific reproductive barriers. One interspecific barrier, known as unilateral incongruity or incompatibility (UI), occurs when species display unidirectional compatibility in interspecific crosses. In the wild tomato species Solanum pennellii, both SI and self-compatible (SC) populations express UI when crossed with domesticated tomato, offering a useful model system to dissect the molecular mechanisms involved in reproductive barriers. In this study, the timing of reproductive barrier establishment during pistil development was determined in SI and SC accessions of S. pennellii using a semi-in vivo system to track pollen-tube growth in developing styles. Both SI and UI barriers were absent in styles 5 days prior to flower opening, but were established by 2 days before flower opening, with partial barriers detected during a transition period 3–4 days before flower opening. The developmental expression dynamics of known SI factors, S-RNases and HT proteins, was also examined. The accumulation of HT-A protein coincided temporally and spatially with UI barriers in developing pistils. Proteomic analysis of stigma/styles from key developmental stages showed a switch in protein profiles from cell-division-associated proteins in immature stigma/styles to a set of proteins in mature stigma/styles that included S-RNases, HT-A protein and proteins associated with cell-wall loosening and defense responses, which could be involved in pollen–pistil interactions. Other prominent proteins in mature stigma/styles were those involved in lipid metabolism, consistent with the accumulation of lipid-rich material during pistil maturation. PMID:23166371
Le Moal, Joëlle; Sharpe, Richard M; Jϕrgensen, Niels; Levine, Hagai; Jurewicz, Joanna; Mendiola, Jaime; Swan, Shanna H; Virtanen, Helena; Christin-Maître, Sophie; Cordier, Sylvaine; Toppari, Jorma; Hanke, Wojciech
2016-02-01
Worrying trends regarding human reproductive endpoints (e.g. semen quality, reproductive cancers) have been reported and there is growing circumstantial evidence for a possible causal link between these trends and exposure to endocrine disrupting chemicals (EDCs). However, there is a striking lack of human data to fill the current knowledge gaps. To answer the crucial questions raised on human reproductive health, there is an urgent need for a reproductive surveillance system to be shared across countries. A multidisciplinary network named HUman Reproductive health and Global ENvironment Network (HURGENT) was created aiming at designing a European monitoring system for reproductive health indicators. Collaborative work allowed setting up the available knowledge to design such a system. Furthermore we conducted an overview of 23 potential indicators, based upon a weight of evidence (WoE) approach according to their potential relation with EDC exposure. The framework and purposes of the surveillance system are settled as well as the approach to select suitable reproductive indicators. The indicators found with the highest scores according to the WoE approach are prostate and breast cancer incidence, sex ratio, endometriosis and uterine fibroid incidence, indicators related to the testicular dysgenesis syndrome, precocious puberty incidence and reproductive hormone levels. Not only sentinel health endpoints, but also diseases with high burdens in public health are highlighted as prior indicators in the context of EDC exposure. Our work can serve as a basis to construct, as soon as possible, the first multi-country reproductive monitoring system. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.
Biedler, James K.; Qi, Yumin; Pledger, David; Macias, Vanessa M.; James, Anthony A.; Tu, Zhijian
2014-01-01
Anopheles stephensi is a principal vector of urban malaria on the Indian subcontinent and an emerging model for molecular and genetic studies of mosquito biology. To enhance our understanding of female mosquito reproduction, and to develop new tools for basic research and for genetic strategies to control mosquito-borne infectious diseases, we identified 79 genes that displayed previtellogenic germline-specific expression based on RNA-Seq data generated from 11 life stage–specific and sex-specific samples. Analysis of this gene set provided insights into the biology and evolution of female reproduction. Promoters from two of these candidates, vitellogenin receptor and nanos, were used in independent transgenic cassettes for the expression of artificial microRNAs against suspected mosquito maternal-effect genes, discontinuous actin hexagon and myd88. We show these promoters have early germline-specific expression and demonstrate 73% and 42% knockdown of myd88 and discontinuous actin hexagon mRNA in ovaries 48 hr after blood meal, respectively. Additionally, we demonstrate maternal-specific delivery of mRNA and protein to progeny embryos. We discuss the application of this system of maternal delivery of mRNA/miRNA/protein in research on mosquito reproduction and embryonic development, and for the development of a gene drive system based on maternal-effect dominant embryonic arrest. PMID:25480960
The reproductive-cell cycle theory of aging: an update.
Atwood, Craig S; Bowen, Richard L
2011-01-01
The Reproductive-Cell Cycle Theory posits that the hormones that regulate reproduction act in an antagonistic pleiotrophic manner to control aging via cell cycle signaling; promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence. Since reproduction is the most important function of an organism from the perspective of the survival of the species, if reproductive-cell cycle signaling factors determine the rate of growth, determine the rate of development, determine the rate of reproduction, and determine the rate of senescence, then by definition they determine the rate of aging and thus lifespan. The theory is able to explain: 1) the simultaneous regulation of the rate of aging and reproduction as evidenced by the fact that environmental conditions and experimental interventions known to extend longevity are associated with decreased reproductive-cell cycle signaling factors, thereby slowing aging and preserving fertility in a hostile reproductive environment; 2) two phenomena that are closely related to species lifespan-the rate of growth and development and the ultimate size of the animal; 3). the apparent paradox that size is directly proportional to lifespan and inversely proportional to fertility between species but vice versa within a species; 4). how differing rates of reproduction between species is associated with differences in their lifespan; 5). why we develop aging-related diseases; and 6). an evolutionarily credible reason for why and how aging occurs-these hormones act in an antagonistic pleiotrophic manner via cell cycle signaling; promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence (dyosis). In essence, the Reproductive-Cell Cycle Theory can explain aging in all sexually reproductive life forms. Published by Elsevier Inc.
Printing quality control automation
NASA Astrophysics Data System (ADS)
Trapeznikova, O. V.
2018-04-01
One of the most important problems in the concept of standardizing the process of offset printing is the control the quality rating of printing and its automation. To solve the problem, a software has been developed taking into account the specifics of printing system components and the behavior in printing process. In order to characterize the distribution of ink layer on the printed substrate the so-called deviation of the ink layer thickness on the sheet from nominal surface is suggested. The geometric data construction the surface projections of the color gamut bodies allows to visualize the color reproduction gamut of printing systems in brightness ranges and specific color sectors, that provides a qualitative comparison of the system by the reproduction of individual colors in a varying ranges of brightness.
1991-12-06
DSN 343-7322. N fjGARX\\R. GILBERT COL, MS Deputy Chief of Staff for Information Management REPRODUCTION QUALITY NOTICE This document is the best quality...1976. 35. Ogre, P.L.: Karzon, D.T. Distribution of poliovirus antibody in serum, nasopharymrt and alimentary tract folloving segmental limunization...sysemst, In.- Hisholl, DAI. ; Advances in human fertility and reproductive endocrinology. NWe York, Raven Press Books. Ltd; Vol. 2. 1963: 175-199. 52. Tic
Models to study gravitational biology of Mammalian reproduction
NASA Technical Reports Server (NTRS)
Tou, Janet; Ronca, April; Grindeland, Richard; Wade, Charles
2002-01-01
Mammalian reproduction evolved within Earth's 1-g gravitational field. As we move closer to the reality of space habitation, there is growing scientific interest in how different gravitational states influence reproduction in mammals. Habitation of space and extended spaceflight missions require prolonged exposure to decreased gravity (hypogravity, i.e., weightlessness). Lift-off and re-entry of the spacecraft are associated with exposure to increased gravity (hypergravity). Existing data suggest that spaceflight is associated with a constellation of changes in reproductive physiology and function. However, limited spaceflight opportunities and confounding effects of various nongravitational factors associated with spaceflight (i.e., radiation, stress) have led to the development of ground-based models for studying the effects of altered gravity on biological systems. Human bed rest and rodent hindlimb unloading paradigms are used to study exposure to hypogravity. Centrifugation is used to study hypergravity. Here, we review the results of spaceflight and ground-based models of altered gravity on reproductive physiology. Studies utilizing ground-based models that simulate hyper- and hypogravity have produced reproductive results similar to those obtained from spaceflight and are contributing new information on biological responses across the gravity continuum, thereby confirming the appropriateness of these models for studying reproductive responses to altered gravity and the underlying mechanisms of these responses. Together, these unique tools are yielding new insights into the gravitational biology of reproduction in mammals.
Humans are not cooperative breeders but practice biocultural reproduction.
Bogin, Barry; Bragg, Jared; Kuzawa, Christopher
2014-01-01
Alloparental care and feeding of young is often called "cooperative breeding" and humans are increasingly described as being a cooperative breeding species. To critically evaluate whether the human offspring care system is best grouped with that of other cooperative breeders. (1) Review of the human system of offspring care in the light of definitions of cooperative, communal and social breeding; (2) re-analysis of human lifetime reproductive effort. Human reproduction and offspring care are distinct from other species because alloparental behaviour is defined culturally rather than by genetic kinship alone. This system allows local flexibility in provisioning strategies and ensures that care and resources often flow between unrelated individuals. This review proposes the term "biocultural reproduction" to describe this unique human reproductive system. In a re-analysis of human life history data, it is estimated that the intense alloparenting typical of human societies lowers the lifetime reproductive effort of individual women by 14-29% compared to expectations based upon other mammals. Humans are not cooperative breeders as classically defined; one effect of the unique strategy of human biocultural reproduction is a lowering of human lifetime reproductive effort, which could help explain lifespan extension.
Extending color primary set in spectral vector error diffusion by multilevel halftoning
NASA Astrophysics Data System (ADS)
Norberg, Ole; Nyström, Daniel
2013-02-01
Ever since its origin in the late 19th century, a color reproduction technology has relied on a trichromatic color reproduction approach. This has been a very successful method and also fundamental for the development of color reproduction devices. Trichromatic color reproduction is sufficient to approximate the range of colors perceived by the human visual system. However, tricromatic systems only have the ability to match colors when the viewing illumination for the reproduction matches that of the original. Furthermore, the advancement of digital printing technology has introduced printing systems with additional color channels. These additional color channels are used to extend the tonal range capabilities in light and dark regions and to increase color gamut. By an alternative approach the addition color channels can also be used to reproduce the spectral information of the original color. A reproduced spectral match will always correspond to original independent of lighting situation. On the other hand, spectral color reproductions also introduce a more complex color processing by spectral color transfer functions and spectral gamut mapping algorithms. In that perspective, spectral vector error diffusion (sVED) look like a tempting approach with a simple workflow where the inverse color transfer function and halftoning is performed simultaneously in one single operation. Essential for the sVED method are the available color primaries, created by mixing process colors. Increased numbers of as well as optimal spectral characteristics of color primaries are expected to significantly improve the color accuracy of the spectral reproduction. In this study, sVED in combination with multilevel halftoning has been applied on a ten channel inkjet system. The print resolution has been reduced and the underlying physical high resolution of the printer has been used to mix additional primaries. With ten ink channels and halfton cells built-up by 2x2 micro dots where each micro dot can be a combination of all ten inks the number of possible ink combinations gets huge. Therefore, the initial study has been focused on including lighter colors to the intrinsic primary set. Results from this study shows that by this approach the color reproduction accuracy increases significantly. The RMS spectral difference to target color for multilevel halftoning is less than 1/6 of the difference achieved by binary halftoning.
Sexual and reproductive health and rights in public health education.
Allotey, Pascale A; Diniz, Simone; Dejong, Jocelyn; Delvaux, Thérèse; Gruskin, Sofia; Fonn, Sharon
2011-11-01
This paper addresses the challenges faced in mainstreaming the teaching of sexual and reproductive health and rights into public health education. For this paper, we define sexual and reproductive health and rights education as including not only its biomedical aspects but also an understanding of its history, values and politics, grounded in gender politics and social justice, addressing sexuality, and placed within a broader context of health systems and global health. Using a case study approach with an opportunistically selected sample of schools of public health within our regional contexts, we examine the status of sexual and reproductive health and rights education and some of the drivers and obstacles to the development and delivery of sexual and reproductive health and rights curricula. Despite diverse national and institutional contexts, there are many commonalities. Teaching of sexual and reproductive health and rights is not fully integrated into core curricula. Existing initiatives rely on personal faculty interest or short-term courses, neither of which are truly sustainable or replicable. We call for a multidisciplinary and more comprehensive integration of sexual and reproductive health and rights in public health education. The education of tomorrow's public health leaders is critical, and a strategy is needed to ensure that they understand and are prepared to engage with the range of sexual and reproductive health and rights issues within their historical and political contexts. Copyright © 2011 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
Sexual and reproductive health and rights in the post-2015 development agenda.
Sen, Gita
2014-01-01
Women's health is currently shaped by the confluence of two important policy trends - the evolution of health system reform policies and from the early 1990s onwards, a strong articulation of a human rights-based approach to health that has emphasised laws and policies to advance gender equality and sexual and reproductive health and rights (SRHR). The drive for sexual and reproductive rights represents an inclusive trend towards human rights to health that goes beyond the right to health services, directing attention to girls' and women's rights to bodily autonomy, integrity and choice in relation to sexuality and reproduction. Such an expanded concept of the right to health is essential if laws, policies and programmes are to respect, protect and fulfil the health of girls and women. However, this expanded understanding has been ghettoised from the more mainstream debates on the right to health and was only partially included in the Millennium Development Goals. The paper argues in favour of a twofold approach in placing SRHR effectively in the context of the post-2015 development agenda: first, firmly ground it in an inclusive approach to the right to health; and second, drawing on two decades of national-level implementation, propose a forward-looking agenda focusing on quality, equality and accountability in policies and in programmes. This can build on good practice while addressing critical challenges central to the development framework itself.
USDA-ARS?s Scientific Manuscript database
Type of heifer development system can have major impact on the future productivity and retention rate of the cowherd. Therefore, the objective of this experiment was to determine growth, reproductive performance, retention rate, and economic efficiency of heifer’s developed in a range raised (with ...
Hayes, Donald K; Fan, Amy Z; Smith, Ruben A; Bombard, Jennifer M
2011-11-01
Some potentially modifiable risk factors and chronic conditions cause significant disease and death during pregnancy and promote the development of chronic disease. This study describes recent trends of modifiable risk factors and controllable chronic conditions among reproductive-aged women. Data from the 2001 to 2009 Behavioral Risk Factor Surveillance System, a representative state-based telephone survey of health behavior in US adults, was analyzed for 327,917 women of reproductive age, 18 to 44 years. We calculated prevalence ratios over time to assess trends for 4 selected risk factors and 4 chronic conditions, accounting for age, race/ethnicity, education, health care coverage, and individual states. From 2001 to 2009, estimates of 2 risk factors improved: smoking declined from 25.9% to 18.8%, and physical inactivity declined from 25.0% to 23.0%. One risk factor, heavy drinking, did not change. From 2003 to 2009, the estimates for 1 risk factor and 4 chronic conditions worsened: obesity increased from 18.3% to 24.7%, diabetes increased from 2.1% to 2.9%, high cholesterol increased from 10.3% to 13.6%, asthma increased from 13.5% to 16.2%, and high blood pressure increased from 9.0% to 10.1%. All trends were significant after adjustment, except that for heavy drinking. Among women of reproductive age, prevalence of smoking and physical inactivity improved, but prevalence of obesity and all 4 chronic conditions worsened. Understanding reasons for the improvements in smoking and physical activity may support the development of targeted interventions to reverse the trends and help prevent chronic disease and adverse reproductive outcomes among women in this age group.
Khendek, A; Chakraborty, A; Roche, J; Ledoré, Y; Personne, A; Policar, T; Żarski, D; Mandiki, R; Kestemont, P; Milla, S; Fontaine, P
2018-02-08
Pikeperch (Sander lucioperca) is a highly valuable fish in Europe. However, development of aquaculture of pikeperch is highly limited due to seasonality of production. This can be overcome by the controlled reproduction of domesticated fish. The first steps of domestication process may induce changes at anatomical, physiological and molecular levels, thereby affecting a variety of biological functions. While there is abundant literature on their effects on stress and growth for example, these effects on reproduction received limited attention notably in pikeperch, a promising candidate for the development of aquaculture. To answer the question of this life-history effect on pikeperch's reproduction, we compared two groups (weight: 1 kg) originated from Czech Republic and with the same domestication level (F0). The first group was a recirculating aquatic system cultured one (2 years, previously fed with artificial diet, never exposed to natural changes in temperature/photoperiod conditions) and the second one was a pond cultured group (3 to 4 years, bred under natural feeding and temperature/photoperiod). The wild group successfully spawned, while the farmed one did not spawn at all. During the program, gonadosomatic indexes of both males and females were significantly higher for the wild fish, as well as the sexual steroids. Gene expression analysis revealed significantly lower LH transcript levels at the pituitary level for the farmed females and lower FSH transcript levels at the pituitary level for the males. In conclusion this study showed that the previous rearing conditions (e.g. culture system, age, diet, etc.) alter the further progress of gametogenesis and the reproductive performances in response to controlled photothermal program for both sexes in pikeperch.
Aagaard, Jan E; George, Renee D; Fishman, Lila; Maccoss, Michael J; Swanson, Willie J
2013-01-01
Understanding the genetic basis of reproductive isolation promises insight into speciation and the origins of biological diversity. While progress has been made in identifying genes underlying barriers to reproduction that function after fertilization (post-zygotic isolation), we know much less about earlier acting pre-zygotic barriers. Of particular interest are barriers involved in mating and fertilization that can evolve extremely rapidly under sexual selection, suggesting they may play a prominent role in the initial stages of reproductive isolation. A significant challenge to the field of speciation genetics is developing new approaches for identification of candidate genes underlying these barriers, particularly among non-traditional model systems. We employ powerful proteomic and genomic strategies to study the genetic basis of conspecific pollen precedence, an important component of pre-zygotic reproductive isolation among yellow monkeyflowers (Mimulus spp.) resulting from male pollen competition. We use isotopic labeling in combination with shotgun proteomics to identify more than 2,000 male function (pollen tube) proteins within maternal reproductive structures (styles) of M. guttatus flowers where pollen competition occurs. We then sequence array-captured pollen tube exomes from a large outcrossing population of M. guttatus, and identify those genes with evidence of selective sweeps or balancing selection consistent with their role in pollen competition. We also test for evidence of positive selection on these genes more broadly across yellow monkeyflowers, because a signal of adaptive divergence is a common feature of genes causing reproductive isolation. Together the molecular evolution studies identify 159 pollen tube proteins that are candidate genes for conspecific pollen precedence. Our work demonstrates how powerful proteomic and genomic tools can be readily adapted to non-traditional model systems, allowing for genome-wide screens towards the goal of identifying the molecular basis of genetically complex traits.
Stenz, Ludwig; Escoffier, Jessica; Rahban, Rita; Nef, Serge; Paoloni-Giacobino, Ariane
2017-01-01
The endocrine disruptor bis(2-ethylhexyl) phthalate (DEHP) has been shown to exert adverse effects on the male animal reproductive system. However, its mode of action is unclear and a systematic analysis of its molecular targets is needed. In the present study, we investigated the effects of prenatal exposure to 300 mg/kg/day DEHP during a critical period for gonads differentiation to testes on male mice offspring reproductive parameters, including the genome-wide RNA expression and associated promoter methylation status in the sperm of the first filial generation. It was observed that adult male offspring displayed symptoms similar to the human testicular dysgenesis syndrome. A combination of sperm transcriptome and methylome data analysis allowed to detect a long-lasting DEHP-induced and robust promoter methylation-associated silencing of almost the entire cluster of the seminal vesicle secretory proteins and antigen genes, which are known to play a fundamental role in sperm physiology. It also resulted in the detection of a DEHP-induced promoter demethylation associated with an up-regulation of three genes apparently not relevant for sperm physiology and partially related to the immune system. As previously reported, DEHP induced an increase in mir-615 microRNA expression and a genome-wide decrease in microRNA promoter methylation. A functional analysis revealed DEHP-induced enrichments in down-regulated gene transcripts coding for peroxisome proliferator-activated receptors and tumor necrosis factor signaling pathways, and in up-regulated gene transcripts coding for calcium binding and numerous myosin proteins. All these enriched pathways and networks have been described to be associated in some way with the reproductive system. This study identifies a large new array of genes dysregulated by DEHP that may play a role in the complex system controlling the development of the male reproductive system.
Cell biology solves mysteries of reproduction.
Sutovsky, Peter
2012-09-01
Reproduction and fertility have been objects of keen inquiry since the dawn of humanity. Medieval anatomists provided the first accurate depictions of the female reproductive system, and early microscopists were fascinated by the magnified sight of sperm cells. Initial successes were achieved in the in vitro fertilization of frogs and the artificial insemination of dogs. Gamete and embryo research was in the cradle of modern cell biology, providing the first evidence of the multi-cellular composition of living beings and pointing out the importance of chromosomes for heredity. In the 20th century, reproductive research paved the way for the study of the cytoskeleton, cell signaling, and the cell cycle. In the last three decades, the advent of reproductive cell biology has brought us human in vitro fertilization, animal cloning, and human and animal embryonic stem cells. It has contributed to the development of transgenesis, proteomics, genomics, and epigenetics. This Special Issue represents a sample of the various areas of reproductive biology, with emphasis on molecular and cell biological aspects. Advances in spermatology, ovarian function, fertilization, and maternal-fetal interactions are discussed within the framework of fertility and diseases such as endometriosis and diabetes.
The ecology and evolutionary endocrinology of reproduction in the human female.
Vitzthum, Virginia J
2009-01-01
Human reproductive ecology (HRE) is the study of the mechanisms that link variation in reproductive traits with variation in local habitats. Empirical and theoretical contributions from biological anthropology, physiology, and demography have established the foundation necessary for developing a comprehensive understanding, grounded in life history theory (LHT), of temporal, individual, and populational variation in women's reproductive functioning. LHT posits that natural selection leads to the evolution of mechanisms that tend to allocate resources to the competing demands of growth, reproduction, and survival such that fitness is locally maximized. (That is, among alternative allocation patterns exhibited in a population, those having the highest inclusive fitness will become more common over generational time.) Hence, strategic modulation of reproductive effort is potentially adaptive because investment in a new conception may risk one's own survival, future reproductive opportunities, and/or current offspring survival. The hypothalamic-pituitary-ovarian (HPO) axis is the principal neuroendocrine pathway by which the human female modulates reproductive functioning according to the changing conditions in her habitat. Adjustments of reproductive investment in a potential conception are manifested in temporal and individual variation in ovarian cycle length, ovulation, hormone levels, and the probability of conception. Understanding the extent and causes of adaptive and non-adaptive variation in ovarian functioning is fundamental to ascertaining the proximate and remote determinants of human reproductive patterns. In this review I consider what is known and what still needs to be learned of the ecology of women's reproductive biology, beginning with a discussion of the principal explanatory frameworks in HRE and the biometry of ovarian functioning. Turning next to empirical studies, it is evident that marked variation between cycles, women, and populations is the norm rather than an aberration. Other than woman's age, the determinants of these differences are not well characterized, although developmental conditions, dietary practices, genetic variation, and epigenetic mechanisms have all been hypothesized to play some role. It is also evident that the reproductive functioning of women born and living in arduous conditions is not analogous to that of athletes, dieters, or even the lower end of the "normal range" of HPO functioning in wealthier populations. Contrary to the presumption that humans have low fecundity and an inefficient reproductive system, both theory and present evidence suggest that we may actually have very high fecundity and a reproductive system that has evolved to be flexible, ruthlessly efficient and, most importantly, strategic. Copyright 2009 Wiley-Liss, Inc.
Novel function of LHFPL2 in female and male distal reproductive tract development.
Zhao, Fei; Zhou, Jun; Li, Rong; Dudley, Elizabeth A; Ye, Xiaoqin
2016-03-11
Congenital reproductive tract anomalies could impair fertility. Female and male reproductive tracts are developed from Müllerian ducts and Wolffian ducts, respectively, involving initiation, elongation and differentiation. Genetic basis solely for distal reproductive tract development is largely unknown. Lhfpl2 (lipoma HMGIC fusion partner-like 2) encodes a tetra-transmembrane protein with unknown functions. It is expressed in follicle cells of ovary and epithelial cells of reproductive tracts. A spontaneous point mutation of Lhfpl2 (LHFPL2(G102E)) leads to infertility in 100% female mice, which have normal ovarian development, ovulation, uterine development, and uterine response to exogenous estrogen stimulation, but abnormal upper longitudinal vaginal septum and lower vaginal agenesis. Infertility is also observed in ~70% mutant males, which have normal mating behavior and sperm counts, but abnormal distal vas deferens convolution resulting in complete and incomplete blockage of reproductive tract in infertile and fertile males, respectively. On embryonic day 15.5, mutant Müllerian ducts and Wolffian ducts have elongated but their duct tips are enlarged and fail to merge with the urogenital sinus. These findings provide a novel function of LHFPL2 and a novel genetic basis for distal reproductive tract development; they also emphasize the importance of an additional merging phase for proper reproductive tract development.
Role of olfaction in Octopus vulgaris reproduction.
Polese, Gianluca; Bertapelle, Carla; Di Cosmo, Anna
2015-01-01
The olfactory system in any animal is the primary sensory system that responds to chemical stimuli emanating from a distant source. In aquatic animals "Odours" are molecules in solution that guide them to locate food, partners, nesting sites, and dangers to avoid. Fish, crustaceans and aquatic molluscs possess sensory systems that have anatomical similarities to the olfactory systems of land-based animals. Molluscs are a large group of aquatic and terrestrial animals that rely heavily on chemical communication with a generally dispersed sense of touch and chemical sensitivity. Cephalopods, the smallest class among extant marine molluscs, are predators with high visual capability and well developed vestibular, auditory, and tactile systems. Nevertheless they possess a well developed olfactory organ, but to date almost nothing is known about the mechanisms, functions and modulation of this chemosensory structure in octopods. Cephalopod brains are the largest of all invertebrate brains and across molluscs show the highest degree of centralization. The reproductive behaviour of Octopus vulgaris is under the control of a complex set of signal molecules such as neuropeptides, neurotransmitters and sex steroids that guide the behaviour from the level of individuals in evaluating mates, to stimulating or deterring copulation, to sperm-egg chemical signalling that promotes fertilization. These signals are intercepted by the olfactory organs and integrated in the olfactory lobes in the central nervous system. In this context we propose a model in which the olfactory organ and the olfactory lobe of O. vulgaris could represent the on-off switch between food intake and reproduction. Copyright © 2014 Elsevier Inc. All rights reserved.
Detecting local establishment strategies of wild cherry (Prunus avium L.).
Höltken, Aki M; Gregorius, Hans-Rolf
2006-10-04
P. avium, a pioneer tree species that colonizes early forest successional stages, is assumed to require an effective strategy allowing stably repeatable rounds of local establishment, dispersal and local extinction. Consequently, the early replacement of cherry by climax tree species makes the establishment of several local generations very unlikely, especially in central European continuous cover forests. This has to be seen in connection with the mixed reproduction system involving asexual reproduction as a complementary adaptational strategy. Tests of the local establishment of wild cherry must therefore consider the possibility of first generation establishment via seedling recruitment potentially followed by an asexual generation (root suckering). Successful establishment can therefore be determined only among adult individuals with the option of detecting vegetative reproduction at these stages. To test the implied suggestion about local establishment strategies of wild cherry, nuclear microsatellites were used to analyse patterns of asexual propagation among adult stages that have been subjected to one of two major types of forest management. These management types, the historical "coppice with standards system" (CWS) and the "high forest system" (HFS), can be reasonably assumed to have affected the reproduction system of P. avium. Clear differences were found in the reproduction pattern between two stands representing the two forest management types: 1) Clonal propagation is observed in both management systems, but with a distinctly higher frequency in the CWS. Hence, sexual recruitment as a first local generation is followed by a second asexual generation in both, whereas in the CWS there is evidence for an additional clonal generation. 2) The estimation of amounts of clonal reproduction critically depends on the assumptions about multilocus gene associations. This is revealed by the application of newly developed methods of quantifying gene associations. 3) Haplotype diversities are higher in the CWS and found to be associated with a large degree of heterozygosity for the second largest clonal group. 4) Seed set was sparse over the last eight years of observation in the CWS stand. This study provides useful guidelines for more comprehensive investigations, particularly on the interrelationships between degrees of cloning and capacity of sexual reproduction, amounts of multilocus gene associations, effects of heterozygosity on cloning success, and sustainability of different forest management types.
Impacts of reproductive technologies on beef production in the United States.
Dahlen, Carl; Larson, Jamie; Lamb, G Cliff
2014-01-01
Estimations of world population growth indicate that by the year 2050 we will reach nine billion habitants on earth. These estimates impose a tremendous challenge in the current agricultural systems as food supply will need to increase by 100 % in the next 40 years (Food and Agriculture Organization of the United Nations 2009). Beef will be a primary protein source that will assist in meeting the requirements for a portion of the protein in diets of this expanding global populace. Beef is a high-quality protein that contains all essential amino acids for the human body and also contains additional essential nutrients such as iron, zinc, B vitamins, riboflavin, selenium, choline, and conjugated linoleic acid (CLA). Adopting reproductive technologies at greater rates than currently used is a viable method to dramatically enhance production efficiency of beef cattle enterprises.Artificial insemination (AI), estrous synchronization and fixed-time AI (TAI), semen and embryo cryopreservation, multiple ovulation and embryo transfer (MOET), in vitro fertilization, sex determination of sperm or embryos, and nuclear transfer are technologies that are used to enhance the production efficiency of beef operations. In many cases, the development of these technologies is responsible for significant changes to traditional livestock production practices. However, adoption of these technologies appears to has not grown at the same rate in the United States as other formidable beef producing nations. For example, sales of beef semen for AI increased from 3.3 to 11.9 million units between 1993 and 2011 in Brazil, whereas that in the United States has increased from 2.9 to 3.8 million units during the same period. The significant increases in adoption of reproductive technologies in developing countries is likely as a result of the development of practical estrous synchronization and TAI systems that have allowed beef producers the opportunity to eliminate detection of estrus in their AI programs with a high degree of success. In the United States, slow adoption rates of these technologies may result in a future loss of international market share of beef products as other nations take advantage not only of the additional kilogram of beef that can be produced but also the improved quality of beef that can be realized through incorporation of reproductive technologies and resultant genetic improvement. However, current difficulties the US producers have with the incorporation of applied reproductive technologies, such as TAI, MOET, and sex semen, must not be the reason to overlook and incorporate more traditional reproductive technologies such as castration, breeding season management, or weaning. In many cases, beef producers in the United States fail to incorporate these more traditional technologies, which results in a reduction in production efficiency of the US beef industry. This chapter will focus on both traditional and more developed reproductive technologies that will play a role in enhancing future production efficiencies of the US beef cattle production system.
76 FR 48184 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-08
... developed regulations for the establishment of a permit system for various activities in Antarctica and... establish such a permit system to designate Antarctic Specially Protected Areas. The applications received... established in 1986 studying the foraging ecology, population dynamics, census and reproductive success and...
Ovarian function's role during cancer cachexia progression in the female mouse.
Hetzler, Kimbell L; Hardee, Justin P; LaVoie, Holly A; Murphy, E Angela; Carson, James A
2017-05-01
Cachexia is a debilitating condition that occurs with chronic disease, including cancer; our research has shown that some regulation of cancer cachexia progression is affected by sex differences. The Apc Min/+ mouse is genetically predisposed to develop intestinal tumors; IL-6 signaling and hypogonadism are associated with cachexia severity in the male. This relationship in the female warrants further investigation, as we have shown that the ability of IL-6 to induce cachexia differs between the sexes. Since ovarian reproductive function relies on a complex system of endocrine signaling to affect whole body homeostasis, we examined the relationship between ovarian reproductive function and progression of cancer cachexia in the female Apc Min/+ mouse. Our study of ovarian reproductive function in female Apc Min/+ mice showed disease-related cessation of estrous cycling (acyclicity) in 38% of mice. Acyclicity, including morphological and functional losses and enhanced muscle inflammatory gene expression, was associated with severe cachexia. Interestingly, ovariectomy rescued body weight and muscle mass and function but increased muscle sensitivity to systemic IL-6 overexpression. In conclusion, our results provide evidence for a relationship between ovarian reproductive function and cachexia progression in female Apc Min/+ mice. Copyright © 2017 the American Physiological Society.
Ovarian function’s role during cancer cachexia progression in the female mouse
Hetzler, Kimbell L.; Hardee, Justin P.; LaVoie, Holly A.; Murphy, E. Angela
2017-01-01
Cachexia is a debilitating condition that occurs with chronic disease, including cancer; our research has shown that some regulation of cancer cachexia progression is affected by sex differences. The ApcMin/+ mouse is genetically predisposed to develop intestinal tumors; IL-6 signaling and hypogonadism are associated with cachexia severity in the male. This relationship in the female warrants further investigation, as we have shown that the ability of IL-6 to induce cachexia differs between the sexes. Since ovarian reproductive function relies on a complex system of endocrine signaling to affect whole body homeostasis, we examined the relationship between ovarian reproductive function and progression of cancer cachexia in the female ApcMin/+ mouse. Our study of ovarian reproductive function in female ApcMin/+ mice showed disease-related cessation of estrous cycling (acyclicity) in 38% of mice. Acyclicity, including morphological and functional losses and enhanced muscle inflammatory gene expression, was associated with severe cachexia. Interestingly, ovariectomy rescued body weight and muscle mass and function but increased muscle sensitivity to systemic IL-6 overexpression. In conclusion, our results provide evidence for a relationship between ovarian reproductive function and cachexia progression in female ApcMin/+ mice. PMID:28292759
Seminal plasma as a diagnostic fluid for male reproductive system disorders.
Drabovich, Andrei P; Saraon, Punit; Jarvi, Keith; Diamandis, Eleftherios P
2014-05-01
Molecular biomarkers hold promise to advance the noninvasive diagnosis of male reproductive system disorders and facilitate the identification and management of these conditions through screening, early diagnosis and more accurate prognosis. Seminal plasma has great potential as a proximal fluid for protein biomarker discovery and as a clinical sample for noninvasive diagnostics. The seminal plasma proteome contains thousands of proteins and includes a large number of tissue-specific proteins that might accurately indicate a pathological process in the tissue of origin. Potential protein biomarkers for male reproductive system disorders are more abundant in seminal plasma than in blood serum or urine, and, therefore, are more easily identified and quantified in semen by mass spectrometry and other techniques. These methods have enabled elaboration of the composition of the seminal plasma proteome and the tissue specificity of seminal plasma proteins. Strategies have been developed to discover protein biomarkers in seminal plasma through integrated 'omics' approaches. Biomarkers of male infertility and prostate cancer are now emerging, and it is evident that seminal plasma has the potential to complement other diagnostic tools available in urology clinics.
A Mathematical Model Of Dengue-Chikungunya Co-Infection In A Closed Population
NASA Astrophysics Data System (ADS)
Aldila, Dipo; Ria Agustin, Maya
2018-03-01
Dengue disease has been a major health problem in many tropical and sub-tropical countries since the early 1900s. On the other hand, according to a 2017 WHO fact sheet, Chikungunya was detected in the first outbreak in 1952 in Tanzania and has continued increasing until now in many tropical and sub-tropical countries. Both these diseases are vector-borne diseases which are spread by the same mosquito, i.e. the female Aedes aegypti. According to the WHO report, there is a great possibility that humans and mosquitos might be infected by dengue and chikungunya at the same time. Here in this article, a mathematical model approach will be used to understand the spread of dengue and chikungunya in a closed population. A model is developed as a nine-dimensional deterministic ordinary differential equation. Equilibrium points and their local stability are analyzed analytically and numerically. We find that the basic reproduction number, the endemic indicator, is given by the maximum of three different basic reproduction numbers of a complete system, i.e. basic reproduction numbers for dengue, chikungunya and for co-infection between dengue and chikungunya. We find that the basic reproduction number for the co-infection sub-system dominates other basic reproduction numbers whenever it is larger than one. Some numerical simulations are provided to confirm these analytical results.
24 CFR 3500.9 - Reproduction of settlement statements.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Reproduction of settlement... HOUSING AND URBAN DEVELOPMENT REAL ESTATE SETTLEMENT PROCEDURES ACT § 3500.9 Reproduction of settlement... in sections F and H, respectively. (3) Reproduction of the HUD-1 must conform to the terminology...
ERIC Educational Resources Information Center
Azaola, Marta Cristina
2012-01-01
The paper reflects upon the principles and practice of an alternative educational system operating in rural Mexico in the light of Bourdieu's theory of cultural and social reproduction. Bourdieu's theory seeks to explain processes of reproduction of power relations within schools and society; whereas alternative educational systems seek to expand…
Manipulations of the reproductive system of fishes by means of exogenous chemicals
Patino, R.
1997-01-01
Environmental control of reproductive activity of captive fish is feasible (or potentially feasible) but, with few exceptions, is currently impractical for most species. Therefore, chemical methods of manipulating reproductive activity continue to be widely used in fish production operations worldwide. However, the control of fish reproduction in captivity cannot be exercised without regard to adequate environmental conditions, which can differ markedly for different species. This review provides a synopsis of relevant aspects of fish reproductive physiology and addresses current and promising future chemical methods of sex control, gonadal recrudescence, and spawning. Most research on the control of reproduction in fishes has focused on female physiology because ovarian development and maturation are easily disturbed by environmental stressors. Control of sex ratios by steroid treatment has become a well-established technique for several fish species, but the technique continues to be problematic in some cases. Final gonadal growth and spawning usually can be achieved by implant treatment with gonadotropin-releasing hormone analogs (GnRHa), which in some species have to be applied in combination with dopamine antagonists to enhance responsiveness to GnRHa. However, efforts to accelerate gonadal recrudescence and maturational competence by chemical means have yielded mixed results, reflecting a relative lack of understanding of the basic physiological and biochemic mechanisms controlling these processes. The potential benefits of using reproductive pheromone, to manipulate gonadal development and spawning has been demonstrated in a few species, but further research is needed to determine whether this technique is applicable to fish culture. Because a reliable supply of young fish is critical for the expansion and diversification of fish culture operations, the use of chemicals in combination with adequate environmental conditions to contain gametogenesis and spawning in fishes will continue to be an important tool for the fish culture.
Reproductive tourism and the quest for global gender justice.
Donchin, Anne
2010-09-01
Reproductive tourism is a manifestation of a larger, more inclusive trend toward globalization of capitalist cultural and material economies. This paper discusses the development of cross-border assisted reproduction within the globalized economy, transnational and local structural processes that influence the trade, social relations intersecting it, and implications for the healthcare systems affected. I focus on prevailing gender structures embedded in the cross-border trade and their intersection with other social and economic structures that reflect and impact globalization. I apply a social connection model of responsibility for unjust outcomes and consider strategies to counter structural injustices embedded in this industry. The concluding section discusses policy reforms and proposals for collaborative action to preclude further injustices and extend full human rights to all.
A 25 years experience of group-housed sows–reproduction in animal welfare-friendly systems
2014-01-01
Since January 1 2013, group housing of sows has been compulsory within the European Union (EU) in all pig holdings with more than ten sows. Sows and gilts need to be kept in groups from 4 weeks after service to 1 week before the expected time of farrowing (Article 3(4) of Directive 2008/120/EC on the protection of pigs). The legislation regarding group housing was adopted already in 2001 and a long transitional period was allowed to give member states and producers enough time for adaptation. Even so, group housing of sows still seems to be uncommon in the EU, and is also uncommon in commercial pig farming systems in the rest of the world. In this review we share our experience of the Swedish 25 years of animal welfare legislation stipulating that sows must be loose-housed which de facto means group housed. The two most important concerns related to reproductive function among group-housed sows are the occurrence of lactational oestrus when sows are group-housed during lactation, and the stress that is associated with group housing during mating and gestation. Field and clinical observations in non-lactating, group-housed sows in Sweden suggest that by making basic facts known about the pig reproductive physiology related to mating, we might achieve application of efficient batch-wise breeding without pharmacological interventions. Group housing of lactating sows has some production disadvantages and somewhat lower productivity would likely have to be expected. Recordings of behavioural indicators in different housing systems suggest a lower welfare level in stalled animals compared with group-housed ones. However, there are no consistent effects on the reproductive performance associated with different housing systems. Experimental studies suggest that the most sensitive period, regarding disturbance of reproductive functions by external stressors, is the time around oestrus. We conclude that by keeping sows according to the pig welfare-friendly Directive 2008/120/EC, it is possible to combine group-housing of sows with good reproductive performance and productivity. However, substantially increased research and development is needed to optimize these systems. PMID:24910081
20170312 - Computer Simulation of Developmental ...
Rationale: Recent progress in systems toxicology and synthetic biology have paved the way to new thinking about in vitro/in silico modeling of developmental processes and toxicities, both for embryological and reproductive impacts. Novel in vitro platforms such as 3D organotypic culture models, engineered microscale tissues and complex microphysiological systems (MPS), together with computational models and computer simulation of tissue dynamics, lend themselves to a integrated testing strategies for predictive toxicology. As these emergent methodologies continue to evolve, they must be integrally tied to maternal/fetal physiology and toxicity of the developing individual across early lifestage transitions, from fertilization to birth, through puberty and beyond. Scope: This symposium will focus on how the novel technology platforms can help now and in the future, with in vitro/in silico modeling of complex biological systems for developmental and reproductive toxicity issues, and translating systems models into integrative testing strategies. The symposium is based on three main organizing principles: (1) that novel in vitro platforms with human cells configured in nascent tissue architectures with a native microphysiological environments yield mechanistic understanding of developmental and reproductive impacts of drug/chemical exposures; (2) that novel in silico platforms with high-throughput screening (HTS) data, biologically-inspired computational models of
Computer Simulation of Developmental Processes and ...
Rationale: Recent progress in systems toxicology and synthetic biology have paved the way to new thinking about in vitro/in silico modeling of developmental processes and toxicities, both for embryological and reproductive impacts. Novel in vitro platforms such as 3D organotypic culture models, engineered microscale tissues and complex microphysiological systems (MPS), together with computational models and computer simulation of tissue dynamics, lend themselves to a integrated testing strategies for predictive toxicology. As these emergent methodologies continue to evolve, they must be integrally tied to maternal/fetal physiology and toxicity of the developing individual across early lifestage transitions, from fertilization to birth, through puberty and beyond. Scope: This symposium will focus on how the novel technology platforms can help now and in the future, with in vitro/in silico modeling of complex biological systems for developmental and reproductive toxicity issues, and translating systems models into integrative testing strategies. The symposium is based on three main organizing principles: (1) that novel in vitro platforms with human cells configured in nascent tissue architectures with a native microphysiological environments yield mechanistic understanding of developmental and reproductive impacts of drug/chemical exposures; (2) that novel in silico platforms with high-throughput screening (HTS) data, biologically-inspired computational models of
Kim, Hyun Chul; Lee, Chi Hoon; Hur, Sung Pyu; Kim, Byeong Hoon; Park, Jun Young; Lee, Young Don
2015-03-01
This study investigated possible involvement of photoperiodic regulation in reproductive endocrine system of female olive flounder. To investigate the influence on brain-pituitary axis in endocrine system by regulating photoperiod, compared expression level of Kisspeptin and sbGnRH mRNA in brain and FSH-β, LH-β and GH mRNA in pituitary before and after spawning. Photoperiod was treated natural photoperiod and long photoperiod (15L:9D) conditions from Aug. 2013 to Jun. 2014. Continuous long photoperiod treatment from Aug. (post-spawning phase) was inhibited gonadal development of female olive flounder. In natural photoperiod group, the Kiss2 expression level a significant declined in Mar. (spawning period). And also, FSH-β, LH-β and GH mRNA expression levels were increasing at this period. However, in long photoperiod group, hypothalamic Kiss2, FSH-β, LH-β and GH mRNA expression levels did not show any significant fluctuation. These results suggest that expression of hypothalamic Kiss2, GtH and GH in the pituitary would change in response to photoperiod and their possible involvement of photoperiodic regulation in reproductive endocrine system of the BPG axis.
Reproduction and advances in reproductive studies in carnivores.
Jewgenow, Katarina; Songsasen, Nucharin
2014-01-01
Reproductive mechanisms are extraordinarily diverse among species, even within the same phylogenetic clade. Due to this, it has been difficult to directly apply reproductive technologies developed in human and livestock to genetically manage ex situ wildlife, including carnivores. To date, more common, closely related species, e.g., domestic cats, dogs and ferrets have served as valuable models for developing reproductive technologies for managing rare, endangered carnivores. Artificial insemination and sperm cryopreservation have already been successfully used to manage ex situ populations in some carnivore species, such as the black-footed ferret, cheetah and giant panda. However, technologies aiming at preserving genetics of valuable females have not been fully developed in carnivores, due to the lack of fundamental knowledge about reproductive anatomy and physiology, gamete development, embryogenesis and cryopreservation. The present chapter is divided into two parts. The first part focuses on current knowledge about carnivore reproduction, with emphasis on species diversity in reproductive mechanisms. The second part highlights the progress in reproductive science and related technologies made during the last decade. In addition, we provide examples of how reproductive technologies can contribute to carnivore management and conservation. Although carnivores are comprised of 19 families, we will only focus our attention on four taxonomic groups, including felids, canids, ursids and mustelids.
Understanding plant reproductive diversity.
Barrett, Spencer C H
2010-01-12
Flowering plants display spectacular floral diversity and a bewildering array of reproductive adaptations that promote mating, particularly outbreeding. A striking feature of this diversity is that related species often differ in pollination and mating systems, and intraspecific variation in sexual traits is not unusual, especially among herbaceous plants. This variation provides opportunities for evolutionary biologists to link micro-evolutionary processes to the macro-evolutionary patterns that are evident within lineages. Here, I provide some personal reflections on recent progress in our understanding of the ecology and evolution of plant reproductive diversity. I begin with a brief historical sketch of the major developments in this field and then focus on three of the most significant evolutionary transitions in the reproductive biology of flowering plants: the pathway from outcrossing to predominant self-fertilization, the origin of separate sexes (females and males) from hermaphroditism and the shift from animal pollination to wind pollination. For each evolutionary transition, I consider what we have discovered and some of the problems that still remain unsolved. I conclude by discussing how new approaches might influence future research in plant reproductive biology.
Perspectives on improvement of reproduction in cattle during heat stress in a future Japan.
Kadokawa, Hiroya; Sakatani, Miki; Hansen, Peter J
2012-06-01
Heat stress (HS) causes hyperthermia, and at its most severe form, can lead to death. More commonly, HS reduces feed intake, milk yield, growth rate and reproductive function in many mammals and birds, including the important cattle breeds in Japan. Rectal temperatures greater than 39.0°C and respiration rates greater than 60/min indicate cows are undergoing HS sufficient to affect milk yield and fertility. HS compromises oocyte quality and embryonic development, reduces expression of estrus and changes secretion of several reproductive hormones. One of the most effective ways to reduce the magnitude of HS is embryo transfer, which bypasses the inhibitory effects of HS on the oocyte and early embryo. It may also be possible to select for genetic resistance to HS. Cooling can also improve reproductive performance in cows and heifers, and probably, the most effective cooling systems currently in use are those that couple evaporative cooling with tunnel ventilation or cross ventilation. Its effect on improving reproductive performance in Japan remains to be evaluated. © 2012 The Authors. Animal Science Journal © 2012 Japanese Society of Animal Science.
Wildlife and human populations are affected by contaminants in natural settings. This problem has been a growing concern over the last decade with the realization that various environmental chemicals can alter the development and functioning of endocrine organs, cells and target ...
Instructor's Guide for Human Development Student Modules.
ERIC Educational Resources Information Center
South Carolina State Dept. of Education, Columbia. Office of Vocational Education.
This instructor's guide is designed for use with an accompanying set of 61 student learning modules on human development. Included among the topics covered in the individual modules are the following: consumer and homemaking education (health and nutrition, personal appearance and grooming, puberty, menstruation, the human reproductive system,…
1990: Twenty-Second Annual National Council on Family Relations Media Awards Competition.
ERIC Educational Resources Information Center
Anson, Julie; And Others
1991-01-01
Describes winning videotapes and films of Media Competition in 12 categories: Human Development across the Life Span; Parenting Issues; Nontraditional Family Systems; Marital and Family Issues and Communication; Sexuality and Sex Role Development; Substance Abuse/Addiction; Human Reproduction and Family Planning; Stress, Transition, and Crisis…
DEVELOPMENT OF A TEST SYSTEM TO EVALUATE ENDOCRINE EFFECTS IN BIRDS
An overview of the process and status of the development of one and two generation Japanese quail reproduction studies for regulatory use will be presented from the perspective of members of the subgroup of the OECD Expert Group on Assessment of Endocrine Disrupting Effects in Bi...
Arista, M; Berjano, R; Viruel, J; Ortiz, M Á; Talavera, M; Ortiz, P L
2017-09-01
The transition from outcrossing to selfing is a repeated pattern in angiosperm diversification and according to general theory this transition should occur quickly and mixed reproductive systems should be infrequent. However, a large proportion of flowering plants have mixed reproductive systems, even showing inbreeding depression. Recently, several theoretical studies have shown that mixed mating systems can be stable, but empirical studies supporting these assumptions are still scarce. Hypochaeris salzmanniana, an annual species with populations differing in their self-incompatibility expression, was used as a study case to assess the stability of its mixed reproductive system. Here a descriptive study of the pollination environment was combined with measurements of the stability of the self-incompatibility system, outcrossing rate, reproductive assurance and inbreeding depression in four populations for two consecutive years. The reproductive system of populations exhibited a geographical pattern: the proportion of plants decreased from west to east. Pollinator environment also varied geographically, being less favourable from west to east. The self-incompatibility expression of some populations changed markedly in only one year. After selfing, progeny was mainly self-compatible, while after outcrossing both self-incompatible and self-compatible plants were produced. In general, both reproductive assurance and high inbreeding depression were found in all populations and years. The lowest values of inbreeding depression were found in 2014 in the easternmost populations, which experienced a marked increase in self-compatibility in 2015. The mixed reproductive system of H. salzmanniana seems to be an evolutionarily stable strategy, with selfing conferring reproductive assurance when pollinator attendance is low, but strongly limited by inbreeding depression. The fact that the highest frequencies of self-compatible plants appeared in the environments most unfavourable to pollination suggests that these plants are selected in these sites, although high rates of inbreeding depression should impede the complete loss of self-incompatibility. In H. salzmanniana, year-to-year changes in the frequency of self-incompatible individuals are directly derived from the balance between reproductive assurance and inbreeding depression. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please email: journals.permissions@oup.com
Physical activity and its effects on reproduction.
Redman, Leanne M
2006-05-01
The reproductive system is tightly coupled with energy balance, and thereby changes in the status of energy balance through changes in physical activity can impact on the reproductive system. In light of the new physical activity for health recommendations, it is therefore important to understand the inherent effects, both positive and negative, of physical activity on the reproductive system. At both extremes of the energy spectrum, disorders of chronic energy excess and energy deficiency are characterized by a wide range of reproductive disorders, including menstrual irregularity, anovulation, polycystic ovarian syndrome, and infertility in women, and erectile dysfunction and altered spermatogenesis in men. Although laboratory research indicates that individuals may be able to prevent or reverse reproductive disruptions, either by increasing energy expenditure in cases of energy excess or by dietary reform in cases of energy deficits, there is an acute need for applied research to confirm this idea and to identify mechanisms by which the availability of energy per se regulates reproductive function in humans.
Darde, Thomas A.; Sallou, Olivier; Becker, Emmanuelle; Evrard, Bertrand; Monjeaud, Cyril; Le Bras, Yvan; Jégou, Bernard; Collin, Olivier; Rolland, Antoine D.; Chalmel, Frédéric
2015-01-01
We report the development of the ReproGenomics Viewer (RGV), a multi- and cross-species working environment for the visualization, mining and comparison of published omics data sets for the reproductive science community. The system currently embeds 15 published data sets related to gametogenesis from nine model organisms. Data sets have been curated and conveniently organized into broad categories including biological topics, technologies, species and publications. RGV's modular design for both organisms and genomic tools enables users to upload and compare their data with that from the data sets embedded in the system in a cross-species manner. The RGV is freely available at http://rgv.genouest.org. PMID:25883147
NASA Technical Reports Server (NTRS)
Buckner, J. D.; Council, H. W.; Edwards, T. R.
1974-01-01
Description of the hardware and software implementing the system of time-lapse reproduction of images through interactive graphics (TRIIG). The system produces a quality hard copy of processed images in a fast and inexpensive manner. This capability allows for optimal development of processing software through the rapid viewing of many image frames in an interactive mode. Three critical optical devices are used to reproduce an image: an Optronics photo reader/writer, the Adage Graphics Terminal, and Polaroid Type 57 high speed film. Typical sources of digitized images are observation satellites, such as ERTS or Mariner, computer coupled electron microscopes for high-magnification studies, or computer coupled X-ray devices for medical research.
Sundari Ravindran, T K
2014-05-01
Universal access to sexual and reproductive health services is one of the goals of the International Conference on Population and Development of 1994. The Millennium Development Goals were intended above all to end poverty. Universal access to health and health services are among the goals being considered for the post-2015 agenda, replacing or augmenting the MDGs. Yet we are not only far from reaching any of these goals but also appear to have lost our way somewhere along the line. Poverty and lack of food security have, through their multiple linkages to health and access to health care, deterred progress towards universal access to health services, including for sexual and reproductive health needs. A more insidious influence is neoliberal globalisation. This paper describes neoliberal globalisation and the economic policies it has engendered, the ways in which it influences poverty and food security, and the often unequal impact it has had on women as compared to men. It explores the effects of neoliberal economic policies on health, health systems, and universal access to health care services, and the implications for access to sexual and reproductive health. To be an advocate for universal access to health and health care is to become an advocate against neoliberal globalisation. Copyright © 2014 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
Effects of marine toxins on the reproduction and early stages development of aquatic organisms.
Vasconcelos, Vítor; Azevedo, Joana; Silva, Marisa; Ramos, Vítor
2010-01-19
Marine organisms, and specially phytoplankton species, are able to produce a diverse array of toxic compounds that are not yet fully understood in terms of their main targets and biological function. Toxins such as saxitoxins, tetrodotoxin, palytoxin, nodularin, okadaic acid, domoic acid, may be produced in large amounts by dinoflagellates, cyanobacteria, bacteria and diatoms and accumulate in vectors that transfer the toxin along food chains. These may affect top predator organisms, including human populations, leading in some cases to death. Nevertheless, these toxins may also affect the reproduction of aquatic organisms that may be in contact with the toxins, either by decreasing the amount or quality of gametes or by affecting embryonic development. Adults of some species may be insensitive to toxins but early stages are more prone to intoxication because they lack effective enzymatic systems to detoxify the toxins and are more exposed to the toxins due to a higher metabolic growth rate. In this paper we review the current knowledge on the effects of some of the most common marine toxins on the reproduction and development of early stages of some organisms.
Bubnov, Rostyslav V; Drahulian, Maria V; Buchek, Polina V; Gulko, Tamara P
2018-03-01
Liver fibrosis (LF) is a chronic disease, associated with many collateral diseases including reproductive dysfunction. Although the normal liver has a large regenerative capacity the complications of LF could be severe and irreversible. Hormone and sex-related issues of LF development and interactions with male reproductive have not been finally studied. The aim was to study the reproductive function of male rats in experimental CCl 4 -induced liver fibrosis rat model, and the capability for restoration of both the liver and male reproduction system. Studies were conducted on 20 3-month old Wistar male rats. The experimental animals were injected with freshly prepared 50% olive oil solution of carbohydrate tetrachloride (CCl 4 ). On the 8th week after injection we noted the manifestations of liver fibrosis. The rats were left to self-healing of the liver for 8 weeks. All male rats underwent ultrasound and biopsy of the liver and testes on the 8th and 16th weeks. The male rats were mated with healthy females before CCl 4 injection, after modeling LF on the 8th week, and after self-healing of the liver. Pregnancy was monitored on ultrasound. On the 8th week of experiment we observed ultrasound manifestation of advanced liver fibrosis, including hepatosplenomegaly, portal hypertension. Ultrasound exam of the rat testes showed testicular degeneration, hydrocele, fibrosis, scarring, petrifications, size reduction, and restriction of testicular descent; testes size decreased from 1.24 ± 0.62 ml to 0.61 ± 0.13, p < 0.01. Liver histology showed granular dystrophy of hepatocytes, necrotic areas, lipid inclusions in parenchyma. Rats with liver fibrosis demonstrated severe injury of the reproductive system and altering of fertility: the offspring of male rats with advanced LF was 4.71 ± 0.53 born alive vs 9.55 ± 0.47 born from mating with healthy males, p < 0.001. Eight weeks after last CCl 4 injection, we revealed signs of liver regeneration, significant recovery of its structure. The ALT and AST levels significantly decreased and reached background measurements. As a result of the second interbreeding after liver self-healing no significant difference was found vs previous mating. Carbohydrate tetrachloride induces injury of liver parenchyma evoking fast and severe liver fibrosis, and is associated with irreversible structural and functional changes in testes, reducing fertility, decreasing potential pregnancy rate, and affecting its development. Liver showed high potential to regenerate, however the self-restoring after liver fibrosis was not accompanied with recovery of the reproductive system.
Bellingham, M; Fowler, P A; Amezaga, M R; Whitelaw, C M; Rhind, S M; Cotinot, C; Mandon-Pepin, B; Sharpe, R M; Evans, N P
2010-06-01
Animals and humans are chronically exposed to endocrine disrupting chemicals (EDCs) that are ubiquitous in the environment. There are strong circumstantial links between environmental EDC exposure and both declining human/wildlife reproductive health and the increasing incidence of reproductive system abnormalities. The verification of such links, however, is difficult and requires animal models exposed to 'real life', environmentally relevant concentrations/mixtures of environmental contaminants (ECs), particularly in utero, when sensitivity to EC exposure is high. The present study aimed to determine whether the foetal sheep reproductive neuroendocrine axis, particularly gondotrophin-releasing hormone (GnRH) and galaninergic systems, were affected by maternal exposure to a complex mixture of chemicals, applied to pasture, in the form of sewage sludge. Sewage sludge contains high concentrations of a spectrum of EDCs and other pollutants, relative to environmental concentrations, but is frequently recycled to land as a fertiliser. We found that foetuses exposed to the EDC mixture in utero through their mothers had lower GnRH mRNA expression in the hypothalamus and lower GnRH receptor (GnRHR) and galanin receptor (GALR) mRNA expression in the hypothalamus and pituitary gland. Strikingly, this, treatment had no significant effect on maternal GnRH or GnRHR mRNA expression, although GALR mRNA expression within the maternal hypothalamus and pituitary gland was reduced. The present study clearly demonstrates that the developing foetal neuroendocrine axis is sensitive to real-world mixtures of environmental chemicals. Given the important role of GnRH and GnRHR in the regulation of reproductive function, its known role programming role in utero, and the role of galanin in the regulation of many physiological/neuroendocrine systems, in utero changes in the activity of these systems are likely to have long-term consequences in adulthood and represent a novel pathway through which EC mixtures could perturb normal reproductive function.
Macnab, V; Scott, A P; Katsiadaki, I; Barber, I
2011-09-01
Parasites can impact host reproduction by interfering with host endocrine systems, but the adaptive nature of such effects is disputed. Schistocephalus solidus plerocercoids are parasites of three-spined sticklebacks Gasterosteus aculeatus that are often associated with impaired host reproduction. Here, we relate reproductive behavior and physiology to levels of the androgen 11-ketotestosterone (11KT) in naturally infected and non-infected male sticklebacks from two UK populations. In one population infected males harbored heavy infections and showed uniformly reduced 11KT titres and kidney spiggin (nesting glue protein) content compared to non-infected fish. However in a second population infection levels were more variable and males with smaller infections recorded 11KT and spiggin titres that overlapped those of non-infected fish; among infected males from this population 11KT and kidney spiggin also both correlated negatively with infection severity. Male reproductive behavior correlated closely with 11KT titre in both populations, and infected males with high 11KT levels exhibited normal reproductive behavior. Our results suggest that Schistocephalus infection per se does not block reproductive development in male sticklebacks, and that some male fish may have the ability to breed whilst infected. Our results are not consistent with the hypothesis that Schistocephalus adaptively castrates male hosts via endocrine disruption; rather they support the hypothesis that reproductive disruption is a side effect of the energetic costs of infection. Copyright © 2011 Elsevier Inc. All rights reserved.
Distribution and Biological Effects of Nanoparticles in the Reproductive System.
Liu, Ying; Li, Hongxia; Xiao, Kai
2016-01-01
Nanoparticles have shown great potential in biomedical applications such as imaging probes and drug delivery. However, the increasing use of nanoparticles has raised concerns about their adverse effects on human health and environment. Reproductive tissues and gametes represent highly delicate biological systems with the essential function of transmitting genetic information to the offspring, which is highly sensitive to environmental toxicants. This review aims to summarzie the penetration of physiological barriers (blood-testis barrier and placental barrier), distribution and biological effects of nanoparticles in the reproductive system, which is essential to control the beneficial effects of nanoparticles applications and to avoid their adverse effects on the reproductive system. We referred to a large number of relevant peer-reviewed research articles about the reproductive toxicity of nanoparticles. The comprehensive information was summarized into two parts: physiological barrier penetration and biological effects of nanoparticles in male or female reproductive system; distribution and metabolism of nanoparticles in the reproductive system. The representative examples were also presented in four tables. The in vitro and in vivo studies imply that some nanoparticles are able to cross the blood-testis barrier or placental barrier, and their penetration depends on the physicochemical characteristics of nanoparticles (e.g., composition, shape, particle size and surface coating). The toxicity assays indicate that nanoparticles might induce adverse physiological effects and impede fertility or embryogenesis. The barrier penetration, adverse physiological effects, distribution and metabolism are closely related to physicochemical characteristics of nanoparticles. Further systematic and mechanistic studies using well-characterized nanoparticles, relevant administration routes, and doses relevant to the expected exposure level are required to improve our understanding of biological effects of nanoparticles on the reproductive system.
Naufahu, Jane; Cunliffe, Adam D; Murray, Joanne F
2013-01-01
Melanin-concentrating hormone (MCH) is an anabolic neuropeptide with multiple and diverse physiological functions including a key role in energy homoeostasis. Rodent studies have shown that the ablation of functional MCH results in a lean phenotype, increased energy expenditure and resistance to diet-induced obesity. These findings have generated interest among pharmaceutical companies vigilant for potential anti-obesity agents. Nutritional status affects reproductive physiology and behaviours, thereby optimising reproductive success and the ability to meet energetic demands. This complex control system entails the integration of direct or indirect peripheral stimuli with central effector systems and involves numerous mediators. A role for MCH in the reproductive axis has emerged, giving rise to the premise that MCH may serve as an integratory mediator between those discrete systems that regulate energy balance and reproductive function. Hence, this review focuses on published evidence concerning i) the role of MCH in energy homoeostasis and ii) the regulatory role of MCH in the reproductive axis. The question as to whether the MCH system mediates the integration of energy homoeostasis with the neuroendocrine reproductive axis and, if so, by what means has received limited coverage in the literature; evidence to date and current theories are summarised herein.
Updates in Reproduction Coming from the Endocannabinoid System
Bradshaw, Heather B.
2014-01-01
The endocannabinoid system (ECS) is an evolutionarily conserved master system deeply involved in the central and local control of reproductive functions in both sexes. The tone of these lipid mediators—deeply modulated by the activity of biosynthetic and hydrolyzing machineries—regulates reproductive functions from gonadotropin discharge and steroid biosynthesis to the formation of high quality gametes and successful pregnancy. This review provides an overview on ECS and reproduction and focuses on the insights in the regulation of endocannabinoid production by steroids, in the regulation of male reproductive activity, and in placentation and parturition. Taken all together, evidences emerge that the activity of the ECS is crucial for procreation and may represent a target for the therapeutic exploitation of infertility. PMID:24550985
TAM receptor signaling in development.
Burstyn-Cohen, Tal
2017-01-01
TYRO3, AXL and MERTK comprise the TAM family of receptor protein tyrosine kinases. Activated by their ligands, protein S (PROS1) and growth-arrest-specific 6 (GAS6), they mediate numerous cellular functions throughout development and adulthood. Expressed by a myriad of cell types and tissues, they have been implicated in homeostatic regulation of the immune, nervous, vascular, bone and reproductive systems. The loss-of-function of TAM signaling in adult tissues culminates in the destruction of tissue homeostasis and diseased states, while TAM gain-of-function in various tumors promotes cancer phenotypes. Combinatorial ligand-receptor interactions may elicit different molecular and cellular responses. Many of the TAM regulatory functions are essentially developmental, taking place both during embryogenesis and postnatally. This review highlights current knowledge on the role of TAM receptors and their ligands during these developmental processes in the immune, nervous, vascular and reproductive systems.
Scott, L F; Sundaram, S G; Smith, S
1993-09-01
To define both the limits of a mouse embryo bioassay for quality control in an assisted reproductive technology (ART) program and the areas where it can be effectively used. Embryos at the pronuclear and two-cell stage from three different strains of mice were used to assess the effectiveness of this assay for media quality control using five different media routinely used in ART. Pronuclear and two-cell embryos from CD-1 mice were used to test the ability of a mouse embryo bioassay to control for water quality, contaminants in the culture system, and fluctuations in the environmental conditions using a medium, culture system, and scoring technique that were optimized for this strain. The mouse embryo bioassay is not effective in differentiating media appropriate for supporting human embryo development since the development of mouse embryos in vitro is strain, stage, and media related. However, CD-1 embryos were shown to be sensitive to variations in water quality, pH, temperature, incubator conditions, and contaminants in the system when grown in a protein-free medium optimized for their development. Both total blastocyst number and the cell count in the blastocysts were affected. Pronuclear embryos were more sensitive to perturbations in the culture system than two-cell embryos. A mouse embryo bioassay can be effectively used as a means of quality control of water, chemicals, and contact materials and for technique standardization and training in an assisted reproduction program. All the conditions of the test should be defined, pronuclear embryos should be used, and the end point should be fully expanded blastocysts and/or cell numbers in these blastocysts where appropriate.
Conserved Insulin Signaling in the Regulation of Oocyte Growth, Development, and Maturation
DAS, DEBABRATA; ARUR, SWATHI
2017-01-01
Insulin signaling regulates various aspects of physiology, such as glucose homeostasis and aging, and is a key determinant of female reproduction in metazoans. That insulin signaling is crucial for female reproductive health is clear from clinical data linking hyperinsulinemic and hypoinsulinemic condition with certain types of ovarian dysfunction, such as altered steroidogenesis, polycystic ovary syndrome, and infertility. Thus, understanding the signaling mechanisms that underlie the control of insulin-mediated ovarian development is important for the accurate diagnosis of and intervention for female infertility. Studies of invertebrate and vertebrate model systems have revealed the molecular determinants that transduce insulin signaling as well as which biological processes are regulated by the insulin-signaling pathway. The molecular determinants of the insulin-signaling pathway, from the insulin receptor to its downstream signaling components, are structurally and functionally conserved across evolution, from worms to mammals – yet, physiological differences in signaling still exist. Insulin signaling acts cooperatively with gonadotropins in mammals and lower vertebrates to mediate various aspects of ovarian development, mainly owing to evolution of the endocrine system in vertebrates. In contrast, insulin signaling in Drosophila and Caenorhabditis elegans directly regulates oocyte growth and maturation. In this review, we compare and contrast insulin-mediated regulation of ovarian functions in mammals, lower vertebrates, C. elegans, and Drosophila, and highlight conserved signaling pathways and regulatory mechanisms in general while illustrating insulin’s unique role in specific reproductive processes. PMID:28379636
Lafon, D
2006-10-01
European regulations (transcribed into French law) aimed at protecting employees from chemicals toxic to reproduction enable classification and labelling of such substances, if they are liable to cause an alteration of male or female reproductive functions or capacity, or to induce non-hereditary harmful effects on their offspring. Three categories can be used to classify these substances in two areas, namely their impairment of fertility and their effects on development. This classification is rarely based on epidemiological study results, but most often on those of experimental toxicological studies conducted by substance manufacturers. These reproduction toxicological studies are only compulsory above a certain tonnage placed on the market. The high level of this tonnage means that these tests are effectively only conducted on rare occasions. It is reckoned that there is no reproduction experimental data for over 95% of substances newly placed on the market. These products therefore appear to be reproduction non-toxic only because they have not been tested. This is a major fault in the current labelling system, which does not allow non-toxic products to be differentiated from non-tested products. The future EU regulatory framework for Registration, Evaluation and Authorisation of CHemicals (REACH) will only slightly enhance information in this area. It can be estimated that over 80% of chemical products will not be exhaustively tested for reproduction and nearly 75% will not be tested to any degree.
Effect of endocrine disruptors on male reproduction in humans: why the evidence is still lacking?
Bliatka, D; Lymperi, S; Mastorakos, G; Goulis, D G
2017-05-01
The so-called "endocrine disruption hypothesis" suggests that exposures to endocrine disruption (EDs) during fetal, neonatal and adult life may interfere with the development of reproductive organs and alter semen quality and reproductive hormone production. Even though animal studies provide substantial evidence of adverse effects of EDs on male reproductive system, epidemiological studies in humans arrive at conflicting results. The aim of the present study was to systematically review the literature to locate methodological characteristics of the studies that struggle the formation of an association between EDs and human male reproduction. Such characteristics include: (i) definition of the exposed and the non-exposed population, (ii) age, (iii) insufficient control for confounders, (iv) ED assay and threshold, (v) time parameters of ED exposure, and (vi) study outcomes. Additional issues are: (i) the late effect of an early exposure, (ii) the multiple exposure effect, and (iii) the fact the same ED may exhibit different modes of action. Unfortunately, the nature of the field precludes the conduction of randomized-controlled trials, which could result to etiological associations between EDs and human male reproduction. Consequently, there is a great need to conduct well-designed studies of case-control or cohort type to evaluate EDs effects on human male reproductive health, and apply possible measures that could limit dangerous exposures. © 2017 American Society of Andrology and European Academy of Andrology.
Culture without the petri-dish.
Thompson, Jeremy G
2007-01-01
Automation of oocyte maturation and embryo production techniques is a new and exciting development in the field of reproductive technologies. There are two areas where increased automation is having an impact: in the area of embryo diagnostics and in the process of embryo production itself. Benefits include decreased staffing and skill requirements for production and assessment of embryos, as well as increasing quality management systems by removing the "human" factor. However, the uptake of new technologies is likely to be slow, as costs and the conservative nature of the Assisted Reproduction Technology industry to adopt new techniques.
Oak Regeneration Using the Two-Age System
Jeffrey W. Stringer
2002-01-01
The two studies presented in this paper were completed in southeastern Kentucky and were designed to evaluate acorn production and development of advanced white oak reproduction from fully released white oak (Quercus alba) trees typical of reserve trees in the two age system. Twelve 2 acre 60- to 90-year-old white oak dominated stands were...
Rivillas, Juan Carlos; Devia Rodriguez, Raul; Song, Gloria; Martel, Andréanne
2018-01-01
This paper assesses inequalities in access to reproductive and maternal health services among females affected by forced displacement and sexual and gender-based violence in conflict settings in Colombia. This was accomplished through the following approaches: first, we assessed the gaps and gradients in three selected reproductive and maternal health care services. Second, we analyzed the patterns of inequalities in reproductive and maternal health care services and changes over time. And finally, we identified challenges and strategies for reaching girls and women who are the hardest to reach in conflict settings, in order to accelerate progress towards universal health coverage and to contribute to meeting the Sustainable Development Goals of good health and well-being and gender equality by 2030. Three types of data were required: data about health outcomes (relating to rates of females affected by conflict), information about reproductive and maternal health care services to provide a social dimension to unmask inequalities (unmet needs in family planning, antenatal care and skilled births attendance); and data on the female population. Data sources used include the National Information System for Social Protection, the National Registry of Victims, the National Administrative Department of Statistics, and Demographic Health Survey at three specific time points: 2005, 2010 and 2015. We estimated the slope index of inequality to express absolute inequality (gaps) and the concentration index to expresses relative inequality (gradients), and to understand whether inequality was eliminated over time. Our findings show that even though absolute health care service-related inequalities dropped over time, relative inequalities worsened or remain unchanged. All summary measures still indicated the existence of inequalities as well as common patterns. Our findings suggest that there is a pattern of marginal exclusion and incremental patterns of inequality in the reproductive and maternal health care service provided to female affected by armed conflict. Overall, the effects of conflict continue to threaten reproductive and maternal health in Colombia, impeding progress towards the realization of universal health care (UHC) and reinforcing already-existing inequities. Key messages and steps forward include the need to understand the two distinct patterns of inequalities identified in this study in order to prompt improved general policy responses. Addressing unmet needs in reproductive and maternal health requires supporting gender equality and prioritizing the girls and women in regions with the highest rates of victims of armed conflict, with the objective of leaving no girl or woman behind. This analysis represents the first attempt to analyze coverage-related inequality in reproductive and maternal health care services for female affected by armed conflict in Colombia. As the World Health Organization and global health systems leaders call for more inclusive engagement, this approach may serve as the key to shaping people-centred health systems. In this particular case, health care facilities must be located in close proximity to girls and women in conflict and post-conflict settings in order to deliver essential reproductive and maternal health care services. Finally, reducing inequalities in opportunities would not only promote equity, but also drive sustainable development.
NASA Astrophysics Data System (ADS)
Okita, Ichiro; Tsuchida, Koji
2016-04-01
In haplodiploid insects such as ants, male sexuals develop from unfertilised haploid eggs, while female sexuals and workers develop from fertilized diploid eggs. However, some ant species do not exchange their gene pool between sexes; both male and female sexuals are clonally produced, while workers are sexually produced. To date, three ant species, Wasmannia auropunctata, Vollenhovia emeryi, and Paratrechina longicornis, have been reported to reproduce using such reproductive systems. In this study, we reveal that in one lineage of the ant Cardiocondyla kagutsuchi, male and female sexuals are also clonally produced. In contrast to the abovementioned three species, the workers were not only sexually produced but had recombinant sequences in their nuclear internal transcribed spacer regions, although the recombinant sequences were not detected in male or female sexuals. These results suggest that the lineage likely possesses a mechanism to compensate for the reduction in genetic variation due to clonal reproduction with somatic recombination that occurs within the workers.
Okita, Ichiro; Tsuchida, Koji
2016-04-01
In haplodiploid insects such as ants, male sexuals develop from unfertilised haploid eggs, while female sexuals and workers develop from fertilized diploid eggs. However, some ant species do not exchange their gene pool between sexes; both male and female sexuals are clonally produced, while workers are sexually produced. To date, three ant species, Wasmannia auropunctata, Vollenhovia emeryi, and Paratrechina longicornis, have been reported to reproduce using such reproductive systems. In this study, we reveal that in one lineage of the ant Cardiocondyla kagutsuchi, male and female sexuals are also clonally produced. In contrast to the abovementioned three species, the workers were not only sexually produced but had recombinant sequences in their nuclear internal transcribed spacer regions, although the recombinant sequences were not detected in male or female sexuals. These results suggest that the lineage likely possesses a mechanism to compensate for the reduction in genetic variation due to clonal reproduction with somatic recombination that occurs within the workers.
[Trends on generation and reproduction of knowledge about economic evaluation and health].
Arredondo, A; Parada, I
2001-08-01
This paper identifies the trends and recent progress in the generation and reproduction of knowledge on health economic evaluation. Analysis is organized along nine public health action fields, namely: health determinants and predictors, economic value of health, healthcare demand, healthcare supply, microeconomic evaluation of healthcare, healthcare market balance, evaluation of policy instruments, general evaluation of the health system, and healthcare planning, regulation and supervision. Each action field is defined to place the reader in the proper setting and level of analysis. In addition, thematic research topics developed in each action field are proposed and discussed. The generation and reproduction of knowledge on the different action fields was based on the review of the bibliographic databases MEDLINE and LILACS for the 1992-2000 period. Results lead to the conclusion that development and application of economic evaluation of healthcare has been uneven across different countries and that there is a growing increase of applications starting in 1994, the year of initiation of healthcare reform in Latin America.
Oktem, Ozgur; Guzel, Yılmaz; Aksoy, Senai; Aydin, Elvin; Urman, Bulent
2015-03-01
Systemic lupus erythematosus (SLE) is a chronic autoimmune systemic disease that mainly affects women of reproductive age. Emerging data from recent molecular studies show us that estrogen hormone plays a central role in the development of this disease. By acting via its cognate receptors ERα and ERβ expressed on immune cells, estrogen can modulate immune function in both the innate and adaptive immune responses. Interestingly, estrogen may also evoke autoimmune responses after binding to B lymphocytes leading to the generation of high-affinity autoantibodies and proinflammatory cytokines (so-called estrogen-induced autoimmunity). Unfortunately, reproductive function of young female patients with this disease is commonly compromised by different pathophysiologic processes. First, ovarian reserve is diminished even in the presence of mild disease suggesting a direct impact of the disease itself on ovarian function possibly due to ovarian involvement in the form of autoimmune oophoritis. Second, SLE patients with severe manifestations of the disease are treated with alkylating chemotherapy agent cyclophosphamide. Cyclophosphamide and other drugs of alkylating category have the highest gonadotoxicity. Therefore, SLE patients exposed to cyclophosphamide have a much higher risk of developing infertility and premature ovarian failure than do the counterparts who are treated with other less toxic treatments. Third, the functions of the hypothalamic pituitary ovarian axis are perturbed by chronic inflammatory state. And finally adverse pregnancy outcomes are more commonly observed in SLE patients such as fetal loss, preterm birth, intrauterine fetal growth restriction, preeclampsia-eclampsia, and fetal congenital heart block. We aimed in this review article to provide the readers an update on how estrogen hormone closely interacts with and induces lupus-prone changes in the immune system. We also discuss ovarian function and other reproductive outcomes in SLE patients and the current strategies to preserve their fertility in the light of the most recent evidence-based findings of the clinical trials and molecular studies.
Life Cycle, Pathogenicity, Histopathology, and Host Range of Race 5 of the Barley Root-Knot Nematode
Ediz, Söngul A.; Dickerson, O. J.
1976-01-01
The optimum temperature for development of race 5 of Meloidogyne naasi was 26 C. A life cycle was completed in 34 days. Growth of sorghum was suppressed when inoculated with M. naasi. Observations of M. naasi-infected sorghum roots demonstrated that roots were penetrated just behind the root cap; giant cells were generally initiated either in the procambial region or in very young phloem. When giant cells developed in the cortex, corresponding areas of the vascular system did not have an endodermis, pericycle, or phloem fibers. Nineteen plant species were tested for suitability as hosts for race 5 of M. naasi. Reproduction occurred on 11 of 12 monocotolydenous hosts and none of 7 dicotolydenous hosts. Reproduction often occurred without gall development. PMID:19308227
Räsänen, Katja; Hendry, Andrew P
2014-01-01
Ecological speciation seems to occur readily but is clearly not ubiquitous – and the relative contributions of different reproductive barriers remain unclear in most systems. We here investigate the potential importance of selection against migrants in lake/stream stickleback (Gasterosteus aculeatus) from the Misty Lake system, Canada. This system is of particular interest because one population contrast (Lake vs. Outlet stream) shows very low genetic and morphological divergence, whereas another population contrast (Lake vs. Inlet stream) shows dramatic genetic and morphological divergence apparently without strong and symmetric reproductive barriers. To test whether selection against migrants might solve this “conundrum of missing reproductive isolation”, we performed a fully factorial reciprocal transplant experiment using 225 individually marked stickleback collected from the wild. Relative fitness of the different ecotypes (Lake, Inlet, and Outlet) was assessed based on survival and mass change in experimental enclosures. We found that Inlet fish performed poorly in the lake (selection against migrants in that direction), whereas Lake fish outperformed Inlet fish in all environments (no selection against migrants in the opposite direction). As predicted from their phenotypic and genetic similarity, Outlet and Lake fish performed similarly in all environments. These results suggest that selection against migrants is asymmetric and, together with previous work, indicates that multiple reproductive barriers contribute to reproductive isolation. Similar mosaic patterns of reproductive isolation are likely in other natural systems. PMID:24772291
The male reproductive system - An overview of common problems.
Wijesinha, Sanjiva; Piterman, Leon; Kirby, Catherine N
2013-05-01
Many male reproductive system problems could be perceived as being embarrassing, which may be one of the reasons that they are often not identified in general practice. This article provides an overview of some common problems affecting the male reproductive system, and outlines current treatment options. Erectile dysfunction, premature ejaculation, loss of libido, testicular cancer and prostate disease may cause embarrassment to the patient and, occasionally, the general practitioner. We describe how patients affected by these conditions may present to general practice, and discuss the reasons why they may not present. We also discuss how GPs can overcome difficulties in identifying and dealing with their male patients suffering from male reproductive system issues.
Marijuana, the Endocannabinoid System and the Female Reproductive System.
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.
Daly, Jonathan; Gunn, Ian; Kirby, Nick; Jones, Robert; Galloway, David
2007-09-01
Serial ultrasound examination of four mature female sevengill sharks (Notorynchus cepedianus) was carried out over 18 months. Monitoring the reproductive cycle and development of follicles and fetuses in sharks in a noninvasive manner using this technique has not been reported previously. Sharks were caught out of the "Oceanarium" tank by divers using a specially made catch-out bag, and brought to a holding area for examination. A behavior scoring system was used to monitor the impact of regular handling on the well-being of the animals. Ultrasound showed the growth and regression of follicles in sevengill ovaries, and allowed an approximation of the reproductive stage of these sharks. Monitoring behavior at five time points during the procedure showed that regular handling of sharks for clinical studies could be done with minimal impact on animal welfare. The ability to follow reproductive events in elasmobranches using ultrasonography is an important step in the application of assisted reproductive technology in these species. Assisted reproductive technology, such as monitoring female reproductive cycles and artificial insemination, could potentially be used to maintain genetic diversity and compliment aquaria-based breeding programs for endangered species such as the gray nurse shark (Carcharias taurus). Zoo Biol 26:383-395, 2007. (c) 2007 Wiley-Liss, Inc.
Cryptococcus neoformans sexual reproduction is controlled by a quorum sensing peptide.
Tian, Xiuyun; He, Guang-Jun; Hu, Pengjie; Chen, Lei; Tao, Changyu; Cui, Ying-Lu; Shen, Lan; Ke, Weixin; Xu, Haijiao; Zhao, Youbao; Xu, Qijiang; Bai, Fengyan; Wu, Bian; Yang, Ence; Lin, Xiaorong; Wang, Linqi
2018-06-01
Bacterial quorum sensing is a well-characterized communication system that governs a large variety of collective behaviours. By comparison, quorum sensing regulation in eukaryotic microbes remains poorly understood, especially its functional role in eukaryote-specific behaviours, such as sexual reproduction. Cryptococcus neoformans is a prevalent fungal pathogen that has two defined sexual cycles (bisexual and unisexual) and is a model organism for studying sexual reproduction in fungi. Here, we show that the quorum sensing peptide Qsp1 serves as an important signalling molecule for both forms of sexual reproduction. Qsp1 orchestrates various differentiation and molecular processes, including meiosis, the hallmark of sexual reproduction. It activates bisexual mating, at least in part through the control of pheromone, a signal necessary for bisexual activation. Notably, Qsp1 also plays a major role in the intercellular regulation of unisexual initiation and coordination, in which pheromone is not strictly required. Through a multi-layered genetic screening approach, we identified the atypical zinc finger regulator Cqs2 as an important component of the Qsp1 signalling cascade during both bisexual and unisexual reproduction. The absence of Cqs2 eliminates the Qsp1-stimulated mating response. Together, these findings extend the range of behaviours governed by quorum sensing to sexual development and meiosis.
Interactions between prolactin and kisspeptin to control reproduction.
Donato, Jose; Frazão, Renata
2016-01-01
Prolactin is best known for its effects of stimulating mammary gland development and lactogenesis. However, prolactin is a pleiotropic hormone that is able to affect several physiological functions, including fertility. Prolactin receptors (PRLRs) are widely expressed in several tissues, including several brain regions and reproductive tract organs. Upon activation, PRLRs may exert prolactin's functions through several signaling pathways, although the recruitment of the signal transducer and activator of transcription 5 causes most of the known effects of prolactin. Pathological hyperprolactinemia is mainly due to the presence of a prolactinoma or pharmacological effects induced by drugs that interact with the dopamine system. Notably, hyperprolactinemia is a frequent cause of reproductive dysfunction and may lead to infertility in males and females. Recently, several studies have indicated that prolactin may modulate the reproductive axis by acting on specific populations of hypothalamic neurons that express the Kiss1 gene. The Kiss1 gene encodes neuropeptides known as kisspeptins, which are powerful activators of gonadotropin-releasing hormone neurons. In the present review, we will summarize the current knowledge about prolactin's actions on reproduction. Among other aspects, we will discuss whether the interaction between prolactin and the Kiss1-expressing neurons can affect reproduction and how kisspeptins may become a novel therapeutic approach to treat prolactin-induced infertility.
Dossi, Fábio C A; Cônsoli, Fernando L
2010-01-01
As many other insects with a restricted diet, the citrus psyllid Diaphorina citri Kuwayama, which vector the causing agent of the Huanglongbing, the bacteria Candidatus Liberibacter spp., is intimately associated with symbiotic microorganisms. These mutualist symbionts play a key role on their host nutritional ecology, and are vertically transmitted to the progeny. However, despite the role symbionts play on host development and reproduction, and the growing opportunities of exploitation of the association insect-symbiont to control insect vectored-pathogens, there are very few studies on the host reproductive biology and on the symbiont transovarial transmission. Therefore, we aimed at analyzing the ovary development during D. citri adulthood, and at verifying for the mating requirement as a trigger to initiate ovary development. Newly-emerged D. citri females were grouped as virgin or mated and ovary development was observed during adulthood. Newly-emerged females have immature ovaries, and ovaries remain without any mature eggs until females mate. Once female mates, the vitellogenesis synthesis and uptake are estimulated, and oocytes are quickly developed. Oocytes maturation in ovarioles is metachronic, with only one oocyte developing at a time in each oogenic cycle. Morphological observations of the reproductive system including the ovaries and spermatheca, after the first cluster of eggs is laid, indicated D. citri is polyandrous, and may require multiple mating to develop additional oogenic maturation cycles.
Makita, Yuji
2008-05-01
1,1-Dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE) is the most prevalent metabolite of DDT used as a pesticide before and tributyltin (TBT) compounds are used primarily as antifouling agents on vessels, ships, and aqua culture facilities, as they exert biocidal actions. Currently, p,p'-DDE and TBT are ubiquitously distributed in the environment and bio-accumulated in marine products, especially fish or shellfish. Thus, oral p,p'-DDE and TBT intake through marine products is demonstrated to be rather high in Japan. Consequently, the fetus and neonate will be exposed to p,p'-DDE and TBT via mother. Therefore, effects of perinatal combined exposure to p,p'-DDE and TBT on the female reproductive system after maturation have been investigated in rat female offspring of dams ingesting 125ppm p,p'-DDE (approximately 10mg/kg) and 25ppm TBT (approximately 2mg/kg) during the perinatal period from gestation to lactation. In the present study, no deleterious reproductive outcomes were recognized in p,p'-DDE and/or TBT-treated dams. In contrast, growth retardation had developed in rat female offspring following perinatal exposure to TBT and sustained even after cessation of exposures. Further, reduced ovarian weights with elevated serum follicle-stimulating hormone (FSH) concentrations were observed in the reproductive system of matured female offspring following perinatal exposure to TBT. At present, biological relevance of these alterations remains unknown, but there is a possibility that these alterations lead to reproductive malfunctions in matured female offspring. Copyright © 2007 Elsevier B.V. All rights reserved.
LOW DOSE PESTICIDE EXPOSURE AND ALTERED REPRODUCTIVE SYSTEM DEVELOPMENT IN REPTILES
In: Environmental Sciences in the 21st Century: Paradigms, Opportunities, and Challenges: Abstract Book: SETAC 21st Annual Meeting, 12-16 November 2000, Nashville, TN. Society of Environmental Toxicology and Chemistry, Pensacola, FL. Pp. 99.
Methyl farnesoate levels in male spider crabs exhibiting active reproductive behavior.
Sagi, A; Ahl, J S; Danaee, H; Laufer, H
1994-09-01
The concentration of methyl farnesoate (MF) in the hemolymph and its synthesis by the mandibular organs (MOs) were investigated to determine whether this compound is related to the differences in the size of the reproductive system and the mating behavior among male morphotypes of the spider crab, Libinia emarginata. Large-claw abraded males displayed mating behavior under competitive conditions. They have the largest reproductive systems, their MOs synthesize large amounts of MF in vitro, and the concentration of MF in their hemolymph is high. Small-claw abraded males displayed mating behavior with receptive females only when isolated. These smaller crabs have intermediate-sized reproductive systems, their MOs synthesize the most MF, and they have the highest circulating level of MF relative to their body size. The unabraded males did not display mating behavior; their reproductive systems are smaller; their MO activity is low, as is their circulating level of MF. The strong relationship between MF levels and the intensity of reproductive behavior suggests that MF may be one of the driving forces behind mating behavior in Crustacea.
Windisch, Ricarda; de Savigny, Don; Onadja, Geneviève; Somda, Antoine; Wyss, Kaspar; Sié, Ali; Kouyaté, Bocar
2011-11-01
Organizational changes, increased funding and the demands of HIV antiretroviral (ARV) treatment create particular challenges for governance in the health sector. We assess resource allocation, policy making and integration of the national responses to ARV provision and reproductive health in Burkina Faso, using national and district budgets related to disease burden, policy documents, organizational structures, and coordination and implementation processes. ARV provision represents the concept of a "crisis scenario", in which reforms are pushed due to a perception of urgent need, whereas the national reproductive health programme, which is older and more integrated, represents a "politics-as-usual scenario". Findings show that the early years of the national response to HIV and AIDS were characterized by new institutions with overlapping functions, and failure to integrate with and strengthen existing structures. National and district budget allocations for HIV compared to other interventions were disproportionately high when assessed against burden of disease. Strategic documents for ARV provision were relatively less developed and referred to, compared to those of the Ministry of Health Directorates for HIV and for Family Health and district health planning teams for reproductive health services. Imbalances and new structures potentially trigger important adverse effects which are difficult to remedy and likely to increase due to the dynamics they create. It therefore becomes crucial, from the outset, to integrate HIV/AIDS funding and responses into health systems. Copyright © 2011 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
Prisoners of progress or hostages to fortune?
Morgan, Derek; Nielsen, Linda
1993-01-01
The new reproductive technologies, especially in vitro fertilization (IVF), have extended the possibilities of assisted reproduction to the benefit of the childless couples. At the same time these technologies and their added techniques, however, have fragmented reproduction and exposed the human egg to intervention yet unknown.... These possibilities have legal as well as ethical implications. The challenge is to obtain all the advantages of the reproduction revolution and avoid the disadvantages: to avoid becoming prisoners of progress, but to control the development and guide it in the directions we want. One of the problems is trying to foresee unwarranted consequences. Another is to agree upon which consequences are unwarranted and how they are best avoided or minimized. Although the questions that arise with respect to law, medicine and bioethics are similar all over the world, there are differences of a philosophical, economic, social, political, religious and even geographical nature which are not easily bridged. It is apparent, though, that core approaches are desirable. This article is an attempt to explore the ways in which these determinants have been manipulated in two European [Great Britain, Denmark] legal systems. We are interested in the ways in which those legal systems have been customized to provide temporary answers and marshalling points for regulating reproduction and we seek to make some observations on the ways in which laws, customs and values have been manipulated to produce pictures of the family and the way in which we want -- literally and figuratively -- to conceive of it in the 21st century.
Comprehensive Reproductive System Care Program - Clinical Breast Care Project (CRSCP-CBCP)
2013-01-01
biomedical informatics group here, the ProLogic team, and the MDR Global leader. This Pathology Checklist tablet data capturing system development with...initiative in developing a prototype tablet application using the Pathology Checklist as the first example following a decision made at the last CBCP...enabling surgery within the center. The Breast Imaging Center has a designated Aurora Breast MRI machine. The merging of the Army and Navy Breast
Survivorship Care in Reducing Symptoms in Young Adult Cancer Survivors
2017-10-13
Breast Carcinoma; Cancer Survivor; Depression; Fatigue; Leukemia; Lymphoma; Malignant Bone Neoplasm; Malignant Digestive System Neoplasm; Malignant Female Reproductive System Neoplasm; Malignant Male Reproductive System Neoplasm; Pain; Sleep Disorder; Soft Tissue Sarcoma
Ginther, Anita J.; Carlson, Anne A.; Ziegler, Toni E.; Snowdon, Charles T.
2006-01-01
In cooperatively breeding groups of mammals, reproduction is usually restricted to a small number of individuals within the social group. Sexual development of mammals can be affected by social environment, but we know little regarding effects of the cooperative-breeding system on males. Cotton-top tamarin (Saguinus oedipus oedipus) offspring typically do not reproduce in their natal group, even though they may be physically mature. We examined neonatal and pubertal development in captive male cotton-top tamarins as an example of reproductive development within a cooperative-breeding system and to compare cotton-top tamarins with the general primate model. Puberty was characterized using both hormonal and physical measures. Data were collected on urinary levels of LH, testosterone (T), dihydrotestosterone (DHT), cortisol, and the ratio of DHT to T; testicular development; body weight; and breeding age. We determined that 1) pubertal LH secretion began at Week 37, 2) a surge of T secretion followed at Weeks 41–44, and 3) an increase in the metabolism of T to DHT may have occurred at an average age of 48.6 wk. Most of the rapid weight gain was completed by Week 24, before hormonal increases and rapid scrotal growth. We concluded that rapid pubertal testicular growth in captive cotton-top males was completed by an average 76 wk, but that completion of the individual pubertal spurt can occur between 56 and 122 wk. In a cooperative-breeding system, the opportunity for successful reproduction is dictated by the social environment, but we found no evidence that male offspring were developmentally suppressed in their natal social groups. Our findings suggest that puberty in male New World callitrichid primates occurs more quickly than puberty in Old World primates, even though both have similar patterns of development. PMID:11804940
Knight, Jessica H; Howards, Penelope P; Spencer, Jessica B; Tsagaris, Katina C; Lim, Sam S
2016-01-01
Systemic lupus erythematosus (SLE) disproportionately affects women and often develops during their reproductive years. Research suggests that some women who receive cyclophosphamide as treatment for SLE experience earlier decline in menstrual function, but reproductive health among women with SLE who have not taken this drug is less well understood. This study aims to better understand the relation between SLE and reproduction by assessing early secondary amenorrhoea and pregnancy in women treated with and without cyclophosphamide from a population-based cohort with large numbers of African-Americans. Female patients with SLE, ages 20-40 at time of diagnosis, who were 40 years or older at the time of the survey were included in this analysis (N=147). Participants in the Georgians Organized Against Lupus (GOAL) study were asked about their reproductive histories including early secondary amenorrhoea, defined as loss of menstruation before age 40. Women who were cyclophosphamide naïve had an increased prevalence of early secondary amenorrhoea compared with population estimates, 13-17% compared with 1-5%. Factors associated with early secondary amenorrhoea in women not treated with cyclophosphamide were marital status and receipt of a kidney transplant. Treatment with cyclophosphamide doubled the prevalence after adjustment for patient characteristics. Over 88% of women reported being pregnant at least once, and about 83% of these had a child, but the majority of pregnancies occurred before diagnosis. SLE diagnosed in early adulthood may affect women's reproductive health even if they are not treated with cyclophosphamide. Better understanding of other factors related to reproductive health in this population will improve clinicians' and patients' abilities to make treatment and family planning decisions.
Knight, Jessica H; Howards, Penelope P; Spencer, Jessica B; Tsagaris, Katina C; Lim, Sam S
2016-01-01
Objective Systemic lupus erythematosus (SLE) disproportionately affects women and often develops during their reproductive years. Research suggests that some women who receive cyclophosphamide as treatment for SLE experience earlier decline in menstrual function, but reproductive health among women with SLE who have not taken this drug is less well understood. This study aims to better understand the relation between SLE and reproduction by assessing early secondary amenorrhoea and pregnancy in women treated with and without cyclophosphamide from a population-based cohort with large numbers of African-Americans. Methods Female patients with SLE, ages 20–40 at time of diagnosis, who were 40 years or older at the time of the survey were included in this analysis (N=147). Participants in the Georgians Organized Against Lupus (GOAL) study were asked about their reproductive histories including early secondary amenorrhoea, defined as loss of menstruation before age 40. Results Women who were cyclophosphamide naïve had an increased prevalence of early secondary amenorrhoea compared with population estimates, 13–17% compared with 1–5%. Factors associated with early secondary amenorrhoea in women not treated with cyclophosphamide were marital status and receipt of a kidney transplant. Treatment with cyclophosphamide doubled the prevalence after adjustment for patient characteristics. Over 88% of women reported being pregnant at least once, and about 83% of these had a child, but the majority of pregnancies occurred before diagnosis. Conclusions SLE diagnosed in early adulthood may affect women's reproductive health even if they are not treated with cyclophosphamide. Better understanding of other factors related to reproductive health in this population will improve clinicians' and patients' abilities to make treatment and family planning decisions. PMID:27752335
A novel spatially-explicit condition for the onset of waterborne diseases in complex environments
NASA Astrophysics Data System (ADS)
Mari, L.; Gatto, M.; Bertuzzo, E.; Casagrandi, R.; Righetto, L.; Rodriguez-Iturbe, I.; Rinaldo, A.
2012-12-01
In spatial models of waterborne infections the condition that all the local reproduction numbers be larger than one is neither necessary nor sufficient for outbreaks to occur. Here, to properly determine epidemic onset conditions, we examine the transition from stable to unstable of the disease-free equilibrium of a system of nonlinear differential equations characterizing the evolution of susceptible and infected individuals within their respective settlements, and pathogen concentration in their accessible environment. Two different network connectivity layers are assumed to link human settlements: hydrologic pathways serve as ecological corridors for pathogens, while human mobility acts as disease vehicle through susceptibles contracting the disease and asymptomatic infectives shedding bacteria at their temporary destinations. We show that an epidemic outbreak can be triggered if the dominant eigenvalue of a generalized reproduction matrix G0, suitably accounting for spatial distribution of human settlements, hydrological pathways for pathogen dispersal and pathogen redistribution mechanisms due to human mobility, is larger than unity. Matrix G0 and its dominant eigenvalue thus replace the usual reproduction number whenever spatial effects on disease propagation cannot be ignored. Conversely, our novel criterion decays into the standard onset condition based on local reproduction numbers in nonspatial settings. By analyzing realistic test cases we show that within a connected network system the disease can start even if all the local reproduction numbers are smaller than unity, or might not start even if all the local reproduction numbers are larger than unity. We also show that onset geography in complex environments is linked to the dominant eigenvector of matrix G0. Applications to cholera outbreaks in developing countries demonstrate that our approach can be successfully used for disease prediction and emergency management.
Mammalian target of rapamycin (mTOR): a central regulator of male fertility?
Jesus, Tito T; Oliveira, Pedro F; Sousa, Mário; Cheng, C Yan; Alves, Marco G
2017-06-01
Mammalian target of rapamycin (mTOR) is a central regulator of cellular metabolic phenotype and is involved in virtually all aspects of cellular function. It integrates not only nutrient and energy-sensing pathways but also actin cytoskeleton organization, in response to environmental cues including growth factors and cellular energy levels. These events are pivotal for spermatogenesis and determine the reproductive potential of males. Yet, the molecular mechanisms by which mTOR signaling acts in male reproductive system remain a matter of debate. Here, we review the current knowledge on physiological and molecular events mediated by mTOR in testis and testicular cells. In recent years, mTOR inhibition has been explored as a prime strategy to develop novel therapeutic approaches to treat cancer, cardiovascular disease, autoimmunity, and metabolic disorders. However, the physiological consequences of mTOR dysregulation and inhibition to male reproductive potential are still not fully understood. Compelling evidence suggests that mTOR is an arising regulator of male fertility and better understanding of this atypical protein kinase coordinated action in testis will provide insightful information concerning its biological significance in other tissues/organs. We also discuss why a new generation of mTOR inhibitors aiming to be used in clinical practice may also need to include an integrative view on the effects in male reproductive system.
The Development of a Web-Based Urban Soundscape Evaluation System
NASA Astrophysics Data System (ADS)
Sudarsono, A. S.; Sarwono, J.
2018-05-01
Acoustic quality is one of the important aspects of urban design. It is usually evaluated based on how loud the urban environment is. However, this approach does not consider people’s perception of the urban acoustic environment. Therefore, a different method has been developed based on the perception of the acoustic environment using the concept of soundscape. Soundscape is defined as the acoustic environment perceived by people who are part of the environment. This approach considers the relationship between the sound source, the environment, and the people. The analysis of soundscape considers many aspects such as cultural aspects, people’s expectations, people’s experience of space, and social aspects. Soundscape affects many aspects of human life such as culture, health, and the quality of life. Urban soundscape management and planning must be integrated with the other aspect of urban design, both in the design and the improvement stages. The soundscape concept seeks to make the acoustic environment as pleasant as possible in a space with or without uncomfortable sound sources. Soundscape planning includes the design of physical features to achieve a positive perceptual outcome. It is vital to gather data regarding the relationship between humans and the components of a soundscape, e.g., sound sources, features of the physical environment, the functions of a space, and the expectation of the sound source. The data can be measured and gathered using several soundscape evaluation methods. Soundscape evaluation is usually conducted using in-situ surveys and laboratory experiments using a multi-speaker system. Although these methods have been validated and are widely used in soundscape analysis, there are some limitations in the application. The in-situ survey needs to be done at one time with many people at the same time because it is hard to replicate the acoustic environment. Conversely, the laboratory experiment does not have a problem with the repetition of the experiment. This method requires a room with a multi-speaker reproduction system. This project used a different method to analyse soundscape developed using headphones via the internet. The internet system for data gathering has been established; a website has enabled to reproduce high-quality audio and it has a system to design online questionnaires. Furthermore, the development of a virtual reality system allows the reproduction of virtual audio-visual stimulus on a website. Although the website has an established system to gather the required data, the problem is the validation of the reproduction system for soundscape analysis, which needs to be done with consideration of several factors: the suitable recording system, the effect of headphone variation, the calibration of the system, and the perception result from internet-based acoustic environment reproduction. This study aims to develop and validate a web-based urban soundscape evaluation method. By using this method, the experiment can be repeated easily and data can be gathered from many respondents. Furthermore, the simplicity of the system allows for the application by the stakeholders in urban design. The data gathered from this system is important for the design of an urban area with consideration of the acoustic aspects.
Smith, Steven E.; Schumaker, Karen S.
2016-01-01
The accumulation of sodium in soil (saline conditions) negatively affects plant growth and development. The Salt Overly Sensitive (SOS) pathway in Arabidopsis (Arabidopsis thaliana) functions to remove sodium from the cytosol during vegetative development preventing its accumulation to toxic levels. In this pathway, the SOS3 and CALCINEURIN B-LIKE10 (CBL10) calcium sensors interact with the SOS2 protein kinase to activate sodium/proton exchange at the plasma membrane (SOS1) or vacuolar membrane. To determine if the same pathway functions during reproductive development in response to salt, fertility was analyzed in wild type and the SOS pathway mutants grown in saline conditions. In response to salt, CBL10 functions early in reproductive development before fertilization, while SOS1 functions mostly after fertilization when seed development begins. Neither SOS2 nor SOS3 function in reproductive development in response to salt. Loss of CBL10 function resulted in reduced anther dehiscence, shortened stamen filaments, and aborted pollen development. In addition, cbl10 mutant pistils could not sustain the growth of wild-type pollen tubes. These results suggest that CBL10 is critical for reproductive development in the presence of salt and that it functions in different pathways during vegetative and reproductive development. PMID:26979332
From esterilología to reproductive biology: The story of the Mexican assisted reproduction business.
González-Santos, Sandra P
2016-06-01
This paper provides the first overview of how assisted reproduction emerged and developed in Mexico. In doing so it addresses two broad points: when and how treatments using assisted reproductive technology became common practice within reproductive medicine; and how the Mexican assisted reproduction industry emerged. The paper begins in 1949, when the first medical association dedicated to esterilología - the biomedical area focused on the study of infertility - was established, thus providing the epistemic and professional ground upon which assisted reproductive technology would later thrive. The paper then traces the way in which this biomedical industry developed, from individual doctors in their practices to networks of clinics and from a clinical practice to a reproductive industry. It also describes the different ways in which the professional community and the government have worked towards developing a regulatory frame for the practice of assisted reproduction. The paper is informed by ethnographic work conducted at clinics, conferences, online forums and websites, as well as by analysis of the contemporary national media, government documents and national medical journals from the early mid-twentieth century to the those published today.
Elsen, A.; Lens, K.; Nguyet, D. T. M.; Broos, S.; Stoffelen, R.; De Waele, D.
2001-01-01
Radopholus similis is one of the most damaging nematodes in bananas. Chemical control is currently the most-used method, but nematode control through genetic improvement is widely encouraged. The objective of this study was to establish an aseptic culture system for R. similis and determine whether R. similis can infect and reproduce on in vitro banana plantlets and in vitro Arabidopsis thaliana. In the study's first part, a suitable aseptic culture system was developed using alfalfa callus. Radopholus similis could penetrate and reproduce in the callus. Six weeks after inoculation with 25 females, the reproduction ratio was 26.3 and all vermiform stages were present. The reproduction ratio increased to 223.2 after 12 weeks. Results of a greenhouse test showed that R. similis did not lose its pathogenicity after culturing on alfalfa callus. In the study's second part, the infection and reproduction of the nematodes cultured on the callus were studied on both in vitro banana plantlets and A. thaliana. Radopholus similis infected and reproduced on both banana and A. thaliana. Furthermore, nematode damage was observed in the root systems of both hosts. These successful infections open new perspectives for rapid in vitro screening for resistance in banana cultivars and anti-nematode proteins expressed in A. thaliana. PMID:19266012
Spatially explicit dynamic N-mixture models
Zhao, Qing; Royle, Andy; Boomer, G. Scott
2017-01-01
Knowledge of demographic parameters such as survival, reproduction, emigration, and immigration is essential to understand metapopulation dynamics. Traditionally the estimation of these demographic parameters requires intensive data from marked animals. The development of dynamic N-mixture models makes it possible to estimate demographic parameters from count data of unmarked animals, but the original dynamic N-mixture model does not distinguish emigration and immigration from survival and reproduction, limiting its ability to explain important metapopulation processes such as movement among local populations. In this study we developed a spatially explicit dynamic N-mixture model that estimates survival, reproduction, emigration, local population size, and detection probability from count data under the assumption that movement only occurs among adjacent habitat patches. Simulation studies showed that the inference of our model depends on detection probability, local population size, and the implementation of robust sampling design. Our model provides reliable estimates of survival, reproduction, and emigration when detection probability is high, regardless of local population size or the type of sampling design. When detection probability is low, however, our model only provides reliable estimates of survival, reproduction, and emigration when local population size is moderate to high and robust sampling design is used. A sensitivity analysis showed that our model is robust against the violation of the assumption that movement only occurs among adjacent habitat patches, suggesting wide applications of this model. Our model can be used to improve our understanding of metapopulation dynamics based on count data that are relatively easy to collect in many systems.
USDA-ARS?s Scientific Manuscript database
We developed a novel scoring system to assess spring phenology in a northern red oak clonal seed orchard. The system was used to score between 304 and 364 ramets for three reproductive seasons and place clones into early, middle, and late phenology groups. While the absolute number of clones in ea...
Endoplasmic Reticulum Stress and Homeostasis in Reproductive Physiology and Pathology.
Guzel, Elif; Arlier, Sefa; Guzeloglu-Kayisli, Ozlem; Tabak, Mehmet Selcuk; Ekiz, Tugba; Semerci, Nihan; Larsen, Kellie; Schatz, Frederick; Lockwood, Charles Joseph; Kayisli, Umit Ali
2017-04-08
The endoplasmic reticulum (ER), comprises 60% of the total cell membrane and interacts directly or indirectly with several cell organelles i.e., Golgi bodies, mitochondria and proteasomes. The ER is usually associated with large numbers of attached ribosomes. During evolution, ER developed as the specific cellular site of synthesis, folding, modification and trafficking of secretory and cell-surface proteins. The ER is also the major intracellular calcium storage compartment that maintains cellular calcium homeostasis. During the production of functionally effective proteins, several ER-specific molecular steps sense quantity and quality of synthesized proteins as well as proper folding into their native structures. During this process, excess accumulation of unfolded/misfolded proteins in the ER lumen results in ER stress, the homeostatic coping mechanism that activates an ER-specific adaptation program, (the unfolded protein response; UPR) to increase ER-associated degradation of structurally and/or functionally defective proteins, thus sustaining ER homeostasis. Impaired ER homeostasis results in aberrant cellular responses, contributing to the pathogenesis of various diseases. Both female and male reproductive tissues undergo highly dynamic cellular, molecular and genetic changes such as oogenesis and spermatogenesis starting in prenatal life, mainly controlled by sex-steroids but also cytokines and growth factors throughout reproductive life. These reproductive changes require ER to provide extensive protein synthesis, folding, maturation and then their trafficking to appropriate cellular location as well as destroying unfolded/misfolded proteins via activating ER-associated degradation mediated proteasomes. Many studies have now shown roles for ER stress/UPR signaling cascades in the endometrial menstrual cycle, ovarian folliculogenesis and oocyte maturation, spermatogenesis, fertilization, pre-implantation embryo development and pregnancy and parturition. Conversely, the contribution of impaired ER homeostasis by severe/prolong ER stress-mediated UPR signaling pathways to several reproductive tissue pathologies including endometriosis, cancers, recurrent pregnancy loss and pregnancy complications associated with pre-term birth have been reported. This review focuses on ER stress and UPR signaling mechanisms, and their potential roles in female and male reproductive physiopathology involving in menstrual cycle changes, gametogenesis, preimplantation embryo development, implantation and placentation, labor, endometriosis, pregnancy complications and preterm birth as well as reproductive system tumorigenesis.
Endoplasmic Reticulum Stress and Homeostasis in Reproductive Physiology and Pathology
Guzel, Elif; Arlier, Sefa; Guzeloglu-Kayisli, Ozlem; Tabak, Mehmet Selcuk; Ekiz, Tugba; Semerci, Nihan; Larsen, Kellie; Schatz, Frederick; Lockwood, Charles Joseph; Kayisli, Umit Ali
2017-01-01
The endoplasmic reticulum (ER), comprises 60% of the total cell membrane and interacts directly or indirectly with several cell organelles i.e., Golgi bodies, mitochondria and proteasomes. The ER is usually associated with large numbers of attached ribosomes. During evolution, ER developed as the specific cellular site of synthesis, folding, modification and trafficking of secretory and cell-surface proteins. The ER is also the major intracellular calcium storage compartment that maintains cellular calcium homeostasis. During the production of functionally effective proteins, several ER-specific molecular steps sense quantity and quality of synthesized proteins as well as proper folding into their native structures. During this process, excess accumulation of unfolded/misfolded proteins in the ER lumen results in ER stress, the homeostatic coping mechanism that activates an ER-specific adaptation program, (the unfolded protein response; UPR) to increase ER-associated degradation of structurally and/or functionally defective proteins, thus sustaining ER homeostasis. Impaired ER homeostasis results in aberrant cellular responses, contributing to the pathogenesis of various diseases. Both female and male reproductive tissues undergo highly dynamic cellular, molecular and genetic changes such as oogenesis and spermatogenesis starting in prenatal life, mainly controlled by sex-steroids but also cytokines and growth factors throughout reproductive life. These reproductive changes require ER to provide extensive protein synthesis, folding, maturation and then their trafficking to appropriate cellular location as well as destroying unfolded/misfolded proteins via activating ER-associated degradation mediated proteasomes. Many studies have now shown roles for ER stress/UPR signaling cascades in the endometrial menstrual cycle, ovarian folliculogenesis and oocyte maturation, spermatogenesis, fertilization, pre-implantation embryo development and pregnancy and parturition. Conversely, the contribution of impaired ER homeostasis by severe/prolong ER stress-mediated UPR signaling pathways to several reproductive tissue pathologies including endometriosis, cancers, recurrent pregnancy loss and pregnancy complications associated with pre-term birth have been reported. This review focuses on ER stress and UPR signaling mechanisms, and their potential roles in female and male reproductive physiopathology involving in menstrual cycle changes, gametogenesis, preimplantation embryo development, implantation and placentation, labor, endometriosis, pregnancy complications and preterm birth as well as reproductive system tumorigenesis. PMID:28397763
Shi, Lihong
2017-12-01
This article explores the creation and ramifications of a stratified reproductive system under China's state control of reproduction. Within this system, an emerging group of "new rich" are able to circumvent birth regulations and have unplanned births because of their financial capabilities and social networks. While China's birth-planning policy is meant to be enforced equally for all couples, the unequal access to wealth and bureaucratic power as a result of China's widening social polarization has created disparate reproductive rights and experiences. This article identifies three ways in which reproductive privileges are created. It further explores how a stratified reproductive system under state population control reinforces social polarization. While many socially marginalized couples are unable to register their unplanned children for citizenship status and social benefits, the new rich are able to legitimate their births and transfer their privilege and status to their children, thus reproducing a new generation of elites. © 2016 by the American Anthropological Association.
ERIC Educational Resources Information Center
Peiter, Andrea; And Others
This instructor guide and the corresponding student reference contain seven lessons about animal reproduction for inclusion in Vocational Instructional Management System (VIMS) agricultural education courses. The lessons cover the following topics: the male and female reproductive systems, puberty and the estrous cycle, conception and gestation,…
Reproductive control via eviction (but not the threat of eviction) in banded mongooses
Cant, Michael A.; Hodge, Sarah J.; Bell, Matthew B. V.; Gilchrist, Jason S.; Nichols, Hazel J.
2010-01-01
Considerable research has focused on understanding variation in reproductive skew in cooperative animal societies, but the pace of theoretical development has far outstripped empirical testing of the models. One major class of model suggests that dominant individuals can use the threat of eviction to deter subordinate reproduction (the ‘restraint’ model), but this idea remains untested. Here, we use long-term behavioural and genetic data to test the assumptions of the restraint model in banded mongooses (Mungos mungo), a species in which subordinates breed regularly and evictions are common. We found that dominant females suffer reproductive costs when subordinates breed, and respond to these costs by evicting breeding subordinates from the group en masse, in agreement with the assumptions of the model. We found no evidence, however, that subordinate females exercise reproductive restraint to avoid being evicted in the first place. This means that the pattern of reproduction is not the result of a reproductive ‘transaction’ to avert the threat of eviction. We present a simple game theoretical analysis that suggests that eviction threats may often be ineffective to induce pre-emptive restraint among multiple subordinates and predicts that threats of eviction (or departure) will be much more effective in dyadic relationships and linear hierarchies. Transactional models may be more applicable to these systems. Greater focus on testing the assumptions rather than predictions of skew models can lead to a better understanding of how animals control each other's reproduction, and the extent to which behaviour is shaped by overt acts versus hidden threats. PMID:20236979
Reproductive science as an essential component of conservation biology.
Holt, William V; Brown, Janine L; Comizzoli, Pierre
2014-01-01
In this chapter we argue that reproductive science in its broadest sense has never been more important in terms of its value to conservation biology, which itself is a synthetic and multidisciplinary topic. Over recent years the place of reproductive science in wildlife conservation has developed massively across a wide and integrated range of cutting edge topics. We now have unprecedented insight into the way that environmental change affects basic reproductive functions such as ovulation, sperm production, pregnancy and embryo development through previously unsuspected influences such as epigenetic modulation of the genome. Environmental change in its broadest sense alters the quality of foodstuffs that all animals need for reproductive success, changes the synchrony between breeding seasons and reproductive events, perturbs gonadal and embryo development through the presence of pollutants in the environment and drives species to adapt their behaviour and phenotype. In this book we explore many aspects of reproductive science and present wide ranging and up to date accounts of the scientific and technological advances that are currently enabling reproductive science to support conservation biology.
NASA Astrophysics Data System (ADS)
Kuruma, Yutetsu
2007-10-01
Self-reproduction is one of main properties that define living cells. In order to explore the self-reproduction process for the study of early cells, and to develop a research line somehow connected to the origin of life, we have built up a constructive ‘synthetic cells (minimal cells)’ approach. The minimal cells approach consists in the investigation of the minimal number of elements to accomplish simple cell-like processes like self-reproduction. Such approach belongs to the field of synthetic biology. The minimal cells are reconstructed from a totally reconstituted cell-free protein synthesis system (PURESYSTEM) and liposome compartments as containers. Based on this approach, we synthesized two membrane proteins (enzymes), GPAT and LPAAT, which are involved in the phosphatidic acid biosynthesis in bacteria. Both membrane proteins were successfully synthesized by PURESYSTEM encapsulated inside POPC liposomes. Additionally, the enzymatic activity of GPAT was restored by mixing the expressed enzyme with lipid and by forming liposomes in situ. Through these experimental evidences, here we present a possible model to achieve self-reproduction in minimal cells. Our results would contribute to the idea that early cells could have been built by an extremely small number of genes.
Nanotechnology in reproductive medicine: emerging applications of nanomaterials.
Barkalina, Natalia; Charalambous, Charis; Jones, Celine; Coward, Kevin
2014-07-01
In the last decade, nanotechnology has been extensively introduced for biomedical applications, including bio-detection, drug delivery and diagnostic imaging, particularly in the field of cancer diagnostics and treatment. However, there is a growing trend towards the expansion of nanobiotechnological tools in a number of non-cancer applications. In this review, we discuss the emerging uses of nanotechnology in reproductive medicine and reproductive biology. For the first time, we summarise the available evidence regarding the use of nanomaterials as experimental tools for the detection and treatment of malignant and benign reproductive conditions. We also present an overview of potential applications for nanomaterials in reproductive biology, discuss the benefits and concerns associated with their use in a highly delicate system of reproductive tissues and gametes, and address the feasibility of this innovative and potentially controversial approach in the clinical setting and for investigative research into the mechanisms underlying reproductive diseases. This unique review paper focuses on the emerging use of nanotechnology in reproductive medicine and reproductive biology, highlighting the role of nanomaterials in the detection and treatment of various reproductive conditions, keeping in mind the benefits and potential concerns associated with nanomaterial use in the delicate system of reproductive tissue and gametes. Copyright © 2014 Elsevier Inc. All rights reserved.
Sills, Eric Scott; Healy, Clifford M
2008-01-01
Surrogacy involves one woman (surrogate mother) carrying a child for another person/s (commissioning person/couple), based on a mutual agreement requiring the child to be handed over to the commissioning person/couple following birth. Reasons for seeking surrogacy include situations where a woman has non-functional or absent reproductive organs, or as a remedy for recurrent pregnancy loss. Additionally, surrogacy may find application in any medical context where pregnancy is contraindicated, or where a couple consisting of two males seek to become parents through oocyte donation. Gestational surrogacy is one of the main issues at the forefront of bioethics and the advanced reproductive technologies, representing an important challenge to medical law. This analysis reviews the history of surrogacy and clinical and legal issues pertaining to this branch of reproductive medicine. Interestingly, the Medical Council of Ireland does not acknowledge surrogacy in its current practice guidelines, nor is there specific legislation addressing surrogacy in Ireland at present. We therefore have developed a contract-based model for surrogacy in which, courts in Ireland may consider when confronted with a surrogacy dispute, and formulated a system to resolve any potential dispute arising from a surrogacy arrangement. While the 2005 report by the Commission on Assisted Human Reproduction (CAHR) is an expert opinion guiding the Oireachtas' development of specific legislation governing assisted human reproduction and surrogacy, our report represents independent scholarship on the contractual elements of surrogacy with particular focus on how Irish courts might decide on surrogacy matters in a modern day Ireland. This joint medico-legal collaborative also reviews the contract for services arrangement between the commissioning person/s and the surrogate, and the extent to which the contract may be enforced. PMID:18983640
Ling, Lin; Kokoza, Vladimir A; Zhang, Changyu; Aksoy, Emre; Raikhel, Alexander S
2017-09-19
Hematophagous female mosquitoes transmit numerous devastating human diseases, including malaria, dengue fever, Zika virus, and others. Because of their obligatory requirement of a vertebrate blood meal for reproduction, these mosquitoes need a lot of energy; therefore, understanding the molecular mechanisms linking metabolism and reproduction is of particular importance. Lipids are the major energy store providing the fuel required for host seeking and reproduction. They are essential components of the fat body, a metabolic tissue that is the insect analog of vertebrate liver and adipose tissue. In this study, we found that microRNA-277 (miR-277) plays an important role in regulating mosquito lipid metabolism. The genetic disruption of miR-277 using the CRISPR-Cas9 system led to failures in both lipid storage and ovary development. miR-277 mimic injection partially rescued these phenotypic manifestations. Examination of subcellular localization of FOXO protein via CRISPR-assisted, single-stranded oligodeoxynucleotide-mediated homology-directed repair revealed that insulin signaling is up-regulated in response to miR-277 depletion. In silico target prediction identified that insulin-like peptides 7 and 8 ( ilp7 and ilp8 ) are putative targets of miR-277; RNA immunoprecipitation and a luciferase reporter assay confirmed that ilp7 and ilp8 are direct targets of this miRNA. CRISPR-Cas9 depletion of ilp7 and ilp8 led to metabolic and reproductive defects. These depletions identified differential actions of ILP7 and ILP8 in lipid homeostasis and ovarian development. Thus, miR-277 plays a critical role in mosquito lipid metabolism and reproduction by targeting ilp7 and ilp8 , and serves as a monitor to control ILP7 and ILP8 mRNA levels.
Study of smell and reproductive organs in a mouse model for CHARGE syndrome
Bergman, Jorieke EH; Bosman, Erika A; van Ravenswaaij-Arts, Conny MA; Steel, Karen P
2010-01-01
CHARGE syndrome is a multiple congenital anomaly syndrome characterised by Coloboma, Heart defects, Atresia of choanae, Retardation of growth and/or development, Genital hypoplasia, and Ear anomalies often associated with deafness. It is caused by heterozygous mutations in the CHD7 gene and shows a highly variable phenotype. Anosmia and hypogonadotropic hypogonadism occur in the majority of the CHARGE patients, but the underlying pathogenesis is unknown. Therefore, we studied the ability to smell and aspects of the reproductive system (reproductive performance, gonadotropin-releasing hormone (GnRH) neurons and anatomy of testes and uteri) in a mouse model for CHARGE syndrome, the whirligig mouse (Chd7Whi/+). We showed that Chromodomain Helicase DNA-binding protein 7 (Chd7) is expressed in brain areas involved in olfaction and reproduction during embryonic development. We observed poorer performance in the smell test in adult Chd7Whi/+ mice, secondary either to olfactory dysfunction or to balance disturbances. Olfactory bulb and reproductive organ abnormalities were observed in a proportion of Chd7Whi/+ mice. Hypothalamic GnRH neurons were slightly reduced in Chd7Whi/+ females and reproductive performance was slightly less in Chd7Whi/+ mice. This study shows that the penetrance of anosmia and hypogonadotropic hypogonadism is lower in Chd7Whi/+ mice than in CHARGE patients. Interestingly, many phenotypic features of the Chd7 mutation showed incomplete penetrance in our model mice, despite the use of inbred, genetically identical mice. This supports the theory that the extreme variability of the CHARGE phenotype in both humans and mice might be attributed to variations in the fetal microenvironment or to purely stochastic events. PMID:19809474
Boric Acid Is Reproductively Toxic to Adult Xenopus laevis, but Not Endocrine Active.
Fort, Douglas J; Fort, Troy D; Mathis, Michael B; Ball, R Wayne
2016-11-01
The potential reproductive and endocrine toxicity of boric acid (BA) in the African clawed frog, Xenopus laevis, was evaluated using a 30-day exposure of adult frogs. Adult female and male frogs established as breeders were exposed to a culture water control and 4 target (nominal) test concentrations [5.0, 7.5, 10.0, and 15 mg boron (B)/L, equivalent to 28.5, 42.8, 57.0, and 85.5 mg BA/L] using flow-through diluter exposure system. The primary endpoints measured were adult survival, growth (weight and snout-vent length [SVL]), necropsy data, reproductive fecundity, and development of progeny (F1) from the exposed frogs. Necropsy endpoints included gonad weight, gonado-somatic index (GSI), ovary profile (oocyte normalcy and stage distribution), sperm count, and dysmorphology. Endocrine endpoints included plasma estradiol (E2), testosterone (T), dihydrotestosteone (DHT), gonadal CYP 19 (aromatase), and gonadal 5α-reductase (5-AR). BA exposure to adult female X. laevis increased the proportion of immature oocytes (< stage II) in the ovaries of females, reduced sperm counts and increased sperm cell dysmorphology frequency in male frogs exposed to 15 mg B/L. No effects on the other general, developmental (F1), or endocrine endpoints were observed. Based on the results of the present study, the no observed adverse effects concentration (NOAEC) for the reproductive endpoints was 10 mg B/L; and 15 mg B/L for reproductive fecundity, F1 embryo larval development, and endocrine function. These results confirmed that although BA is capable of inducing reproductive toxicity at high concentrations, it is not an endocrine disrupting agent. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Reproductive health care strategy -- a gender-sensitive approach to family welfare.
Anita
1996-01-01
The author advocates a reproductive health care strategy to revitalize India's family welfare program. A major shift in focus is needed in population policy and programs to incorporate a gender-sensitive approach. That shift should help to clear the path toward improved health status for women and female children. Consensus reached at the UN's 1994 International Conference on Population and Development supported a change in population and development policies, affording women's empowerment, gender equality, and equity greater priority for a meaningful policy of human-centered sustainable development. Reproductive health care, reproductive health in practice, the quality of care in reproductive health, gender equality as a human right, and empowering women are discussed.
Sex-specific impact of prenatal stress on growth and reproductive parameters of guinea pigs.
Schöpper, Hanna; Klaus, Teresa; Palme, Rupert; Ruf, Thomas; Huber, Susanne
2012-12-01
Body condition and reproductive maturation are parameters of reproductive success that are influenced by sexual hormones rising in the circulation during the time of puberty. Various endocrine systems can be programmed by conditions experienced during early life. Stress for instance is supposed to be capable of influencing fetal development, leading to adjustments of offspring's later physiology. We examined whether prenatal stress (induced by exposure to strobe light) during early- to mid-gestation was capable of affecting later reproductive parameters in guinea pigs (Cavia aperea f. porcellus). Therefore, we measured the levels of testosterone and progesterone from the age of day 12-124 in prenatally stressed (PS, n = 20) and unaffected control animals (n = 24). Furthermore, we determined the timing of puberty and growth. Body weight development revealed significantly faster growth in PS females compared to control animals. The onset of first estrus was slightly earlier in PS females, however not significantly so. Cycle lengths and levels of progesterone differed between groups over the course of time with higher progesterone levels and more constant cycles among PS females compared to control females who displayed marked differences between first and subsequent cycles. Levels of testosterone did not differ between groups. We conclude that prenatal stress accelerates growth and maturity in females, but not in males.
Hernández-Prado, Bernardo; Kestler, Edgar; Díaz, Juan; Walker, Dilys; Langer, Ana; Lewis, Sarah; De la Vara-Salazar, Elvia; Melo-Zurita, María del Carmen; Iriarte, Emma; Danel, Isabella; Donnay, France; Alemán, Denis; Serrano, Roselyn; Morales, Evelyn; Largaespada, Natalia; González, José Douglas Jarquín; Hernández, Ma Del Carmen; Mejía, Claudia E Quiroz; González, Geneva; Carrera, Yadira; Valverde, Clelia; Luna, Rufino; Valencia-Mendoza, Atanacio; Sosa-Rubí, Sandra G; Hernández-Prado, Bernardo; Kestler, Edgar; Díaz, Juan; Walker, Dilys; Langer, Ana; Lewis, Sarah; De la Vara-Salazar, Elvia; Melo-Zurita, María Del Carmen
2011-01-01
To present the main results of the regional situation diagnosis and intervention plan developed in 2010 as part of the planning activities of the Mesoamerican Health System by the Working Group on Maternal, Reproductive and Neonatal Health. A group of experts and representatives from countries in the region (Central America and nine southern Mexican states) conducted an exhaustive review of available data to construct a situational analysis and a review of effective practices for improving maternal, reproductive and neonatal health. Finally, the group proposed a regional action plan, defining regional goals and specific interventions. The situational diagnosis suggests that, although there has been progress in the last 10 years, maternal and neonatal mortality rates are still unnaceptably high in the region, with a substantial variability across countries. The group proposed as a regional goal the reduction of maternal and neonatal mortality in accordance with the Millenium Development Goals. The regional plan recommends specific maternal and neonatal health interventions emphasizing obstetric and neonatal emergency care, skilled birth attendance and family planning. The plan also includes a five year implementation strategy, along with training and evaluation strategies. The regional plan for maternal, neonatal and reproductive health has the potential to be successful, provided it is effectively implemented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnston, P.G.; Boshes, M.; Zucker, I.
White-footed mice were maintained in short or long photoperiods from birth to 60 days of age (10 h vs. 14 h of light per day). Testes weights and spermatogenesis were substantially reduced in short daylengths. Pinealectomy at 5-7 days of age eliminated the suppressive effect of photoperiod on the reproductive system. However, testicular development was not retarded in intact males kept from 25 to 60 days of age in short daylengths. Exposure to short daylengths prior to 25 days of age contributes to photoperiodic inhibition of testicular development. Removal of the pineal gland did not consistently affect gonadal maturation inmore » long photoperiods. The pineal gland transduces the effects of short daylengths on reproductive development. Some effects of long daylengths on the neuroendocrine axis of white-footed mice may also be mediated by the pineal gland.« less
Organizational and activational effects of sex steroids on kisspeptin neuron development
Poling, Matthew C.; Kauffman, Alexander S.
2012-01-01
Kisspeptin, encoded by the Kiss1 gene, is a neuropeptide required for puberty and adult reproductive function. Understanding the regulation and development of the kisspeptin system provides valuable knowledge about the physiology of puberty and adult fertility, and may provide insights into human pubertal or reproductive disorders. Recent studies, particularly in rodent models, have assessed how kisspeptin neurons develop and how hormonal and non-hormonal factors regulate this developmental process. Exposure to sex steroids (testosterone and estradiol) during critical periods of development can induce organizational (permanent) effects on kisspeptin neuron development, with respect to both sexually dimorphic and non-sexually dimorphic aspects of kisspeptin biology. In addition, sex steroids can also impart activational (temporary) effects on kisspeptin neurons and Kiss1 gene expression at various times during neonatal and peripubertal development, as they do in adulthood. Here, we discuss the current knowledge—and in some cases, lack thereof—of the influence of hormones and other factors on kisspeptin neuronal development. PMID:22728025
Novo, Sergi; Penon, Oriol; Barrios, Leonardo; Nogués, Carme; Santaló, Josep; Durán, Sara; Gómez-Matínez, Rodrigo; Samitier, Josep; Plaza, José Antonio; Pérez-García, Luisa; Ibáñez, Elena
2013-06-01
Is the attachment of biofunctionalized polysilicon barcodes to the outer surface of the zona pellucida an effective approach for the direct tagging and identification of cultured embryos? The results achieved provide a proof of concept for a direct embryo tagging system using biofunctionalized polysilicon barcodes, which could help to minimize the risk of mismatching errors (mix-ups) in human assisted reproduction technologies. Even though the occurrence of mix-ups is rare, several cases have been reported in fertility clinics around the world. Measures to prevent the risk of mix-ups in human assisted reproduction technologies are therefore required. Mouse embryos were tagged with 10 barcodes and the effectiveness of the tagging system was tested during fresh in vitro culture (n=140) and after embryo cryopreservation (n = 84). Finally, the full-term development of tagged embryos was evaluated (n =105). Mouse pronuclear embryos were individually rolled over wheat germ agglutinin-biofunctionalized polysilicon barcodes to distribute them uniformly around the ZONA PELLUCIDA surface. Embryo viability and retention of barcodes were determined during 96 h of culture. The identification of tagged embryos was performed every 24 h in an inverted microscope and without embryo manipulation to simulate an automatic reading procedure. Full-term development of the tagged embryos was assessed after their transfer to pseudo-pregnant females. To test the validity of the embryo tagging system after a cryopreservation process, tagged embryos were frozen at the 2-cell stage using a slow freezing protocol, and followed in culture for 72 h after thawing. Neither the in vitro or in vivo development of tagged embryos was adversely affected. The tagging system also proved effective during an embryo cryopreservation process. Global identification rates higher than 96 and 92% in fresh and frozen-thawed tagged embryos, respectively, were obtained when simulating an automatic barcode reading system, although these rates could be increased to 100% by simply rotating the embryos during the reading process. The direct embryo tagging developed here has exclusively been tested in mouse embryos. Its effectiveness in other species, such as the human, is currently being tested. The direct embryo tagging system developed here, once tested in human embryos, could provide fertility clinics with a novel tool to reduce the risk of mix-ups in human assisted reproduction technologies.
A critical number of workers in a honeybee colony triggers investment in reproduction
NASA Astrophysics Data System (ADS)
Smith, Michael L.; Ostwald, Madeleine M.; Loftus, J. Carter; Seeley, Thomas D.
2014-10-01
Social insect colonies, like individual organisms, must decide as they develop how to allocate optimally their resources among survival, growth, and reproduction. Only when colonies reach a certain state do they switch from investing purely in survival and growth to investing also in reproduction. But how do worker bees within a colony detect that their colony has reached the state where it is adaptive to begin investing in reproduction? Previous work has shown that larger honeybee colonies invest more in reproduction (i.e., the production of drones and queens), however, the term `larger' encompasses multiple colony parameters including number of adult workers, size of the nest, amount of brood, and size of the honey stores. These colony parameters were independently increased in this study to test which one(s) would increase a colony's investment in reproduction via males. This was assayed by measuring the construction of drone comb, the special type of comb in which drones are reared. Only an increase in the number of workers stimulated construction of drone comb. Colonies with over 4,000 workers began building drone comb, independent of the other colony parameters. These results show that attaining a critical number of workers is the key parameter for honeybee colonies to start to shift resources towards reproduction. These findings are relevant to other social systems in which a group's members must adjust their behavior as a function of the group's size.
Ichii, Osamu; Nakamura, Teppei; Irie, Takao; Kouguchi, Hirokazu; Sotozaki, Kozue; Horino, Taro; Sunden, Yuji; Elewa, Yaser Hosny Ali; Kon, Yasuhiro
2018-03-01
Cotton rat ( Sigmodon hispidus) is a useful experimental rodent for the study of human infectious diseases. We previously clarified that cotton rats, particularly females, developed chronic kidney disease characterized by cystic lesions, inflammation, and fibrosis. The present study investigated female-associated factors for chronic kidney disease development in cotton rats. Notably, female cotton rats developed separation of the pelvic symphysis and hypertrophy in the vaginal parts of the cervix with age, which strongly associated with pyometra. The development of pyometra closely associated with the deterioration of renal dysfunction or immunological abnormalities was indicated by blood urea nitrogen and serum creatinine or spleen weight and serum albumin/globulin ratio, respectively. These parameters for renal dysfunction and immunological abnormalities were statistically correlated. These phenotypes found in the female reproductive organs were completely inhibited by ovariectomy. Further, the female cotton rats with pyometra tended to show more severe chronic kidney disease phenotypes and immunological abnormalities than those without pyometra; these changes were inhibited in ovariectomized cotton rats. With regard to renal histopathology, cystic lesions, inflammation, and fibrosis were ameliorated by ovariectomy. Notably, the immunostaining intensity of estrogen receptor α and estrogen receptor β were weak in the healthy kidneys, but both estrogen receptors were strongly induced in the renal tubules showing cystic changes. In conclusion, the close correlations among female reproductive organ-associated abnormalities, immunological abnormalities, and renal dysfunction characterize the chronic kidney disease features of female cotton rats. Thus, the cotton rat is a unique rodent model to elucidate the pathological crosstalk between chronic kidney disease and sex-related factors. Impact statement The increasing number of elderly individuals in the overall population has led to a concomitant age-related increase in chronic kidney disease. Moreover, the global prevalence of patients with chronic kidney disease is gradually increasing, which poses a serious public health problem. The limited number of spontaneous chronic kidney disease animal models, which resemble chronic kidney disease pathogenesis in elderly individuals, is a major limitation in the development of experimental and curative medicines for chronic kidney disease. This pathological study clarified that sex-related factors, including hormones, and abnormalities of the female reproductive system, such as pyometra, are closely associated with chronic kidney disease development by using cotton rats ( Sigmodon hispidus). Further, ovariectomy inhibited the phenotypes of the female reproductive system, immunological abnormalities, and chronic kidney disease. Thus, this laboratory rodent serves as a novel and useful spontaneous chronic kidney disease model to elucidate the candidate disease factors and the pathogenesis of chronic kidney disease both in human and experimental medicine.
Since humans are exposed to more than one chemical at a time, concern has arisen about the effects of mixtures of chemicals on human reproduction and development. We are conducting studies to determine the 1) classes of chemicals that disrupt sexual differentiation via different ...
Since humans are exposed to more than one chemical at a time, concern has arisen about the effects ofmixtures ofphthalates and other chemicals on human reproduction and development. We are conducting studies to determine 1) what effects associated with in utero phthalate exposure...
Since humans and wildlife are exposed to more than one chemical at a time, concern has arisen about the effects of complex mixtures on reproduction and development. To date, different regulatory groups have not yet developed consistent approaches to conducting assessments of the ...
TOISHI, Yuko; TSUNODA, Nobuo; NAGATA, Shun-ichi; KIRISAWA, Rikio; NAGAOKA, Kentaro; WATANABE, Gen; YANAGAWA, Yojiro; KATAGIRI, Seiji; TAYA, Kazuyoshi
2017-01-01
Testosterone (T) concentration is a useful indicator of reproductive function in male animals. However, T concentration is not usually measured in veterinary clinics, partly due to the unavailability of reliable and rapid assays for animal samples. In this study, a rapid chemiluminescent enzyme immunoassay system (CLEIA system) that was developed for the measurement of T concentration in humans use was validated for stallion blood samples. First, serum T concentrations were measured using the CLEIA system and compared with those measured by a fluoroimmunoassay that has been validated for use in stallions. The serum T concentrations measured by the two methods were highly correlated (r = 0.9865, n = 56). Second, to validate the use of whole blood as assay samples, T concentrations in whole blood and in the serum were measured by the CLEIA system. T concentrations in both samples were highly correlated (r = 0.9665, n = 64). Finally, to evaluate the practical value of the CLEIA system in clinical settings, T concentrations were measured in three stallions with reproductive abnormalities after the administration of human chorionic gonadotropin (hCG). Two stallions with small or absent testes in the scrotum showed an increase in T production in response to hCG administration and one stallion with seminoma did not. In conclusion, the CLEIA system was found to be a rapid and reliable tool for measuring T concentrations in stallions and may improve reproductive management in clinical settings and in breeding studs. PMID:29129877
Modeling adverse environmental impacts on the reproductive system.
Sussman, N B; Mazumdar, S; Mattison, D R
1999-03-01
When priority topics are being established for the study of women's health, it is generally agreed that one important area on which to focus research is reproduction. For example, increasing attention has been directed to environmental exposures that disrupt the endocrine system and alter reproduction. These concerns also suggest the need to give greater attention to the use of animal toxicologic testing to draw inferences about human reproductive risks. Successful reproduction requires multiple simultaneous and sequential processes in both the male and female, and the effect of toxicity on reproduction-related processes is time dependent. Currently, however, the risk assessment approach does not allow for the use of multiple processes or for considering the reproductive process response as a function of time. We discuss several issues in modeling exposure effects on reproductive function for risk assessment and present an overview of approaches for reproductive risk assessment. Recommendations are provided for an effective animal study design for determining reproductive risk that addresses optimization of the duration of dosing, observation of the effects of exposure on validated biomarkers, analysis of several biomarkers for complete characterization of the exposure on the underlying biologic processes, the need for longitudinally observed exposure effects, and a procedure for estimating human reproductive risk from the animal findings. An approach to characterizing reproductive toxicity to estimate the increased fertility risks in a dibromochloropropane (DBCP)-exposed human population is illustrated, using several reproductive biomarkers simultaneously from a longitudinal rabbit inhalation study of DBCP and an interspecies extrapolation method.
Development of a Novel Tissue Specific Aromatase Activity Regulation Therapeutic Method
2009-09-01
Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Estrogen is essential for normal growth and development of the female ...the ovaries and other tissues of the body using an enzyme called aromatase. Once women have reached menopause, the ovaries no longer produce estrogen...Introduction Estrogen is essential for normal growth and development of the female reproductive system, including breast tissue, and lifetime
NASA Technical Reports Server (NTRS)
Duncan, S.
1984-01-01
Technological goals for a silicon dendritic web growth program effort are presented. Principle objectives for this program include: (1) grow long web crystals front continuously replenished melt; (2) develop temperature distribution in web and melt; (3) improve reproductibility of growth; (4) develop configurations for increased growth rates (width and speed); (5) develop new growth system components as required for improved growth; and (6) evaluate quality of web growth.
The impact of corruption on the sustainable development of human capital
NASA Astrophysics Data System (ADS)
Absalyamova, Svetlana; Absalyamov, Timur; Khusnullova, Asiya; Mukhametgalieva, Chulpan
2016-08-01
The article explains the use of the human capital sustainable development index (HCSDI) to assess the quality of the reproduction of human capital. The paper provides the algorithm for calculating HCSDI and its components. Authors estimated cross-country differences of HCSDI and developed econometric model of the impact of corruption on HCSDI. The use of this model has allowed to reveal the mechanism and assess the impact of corruption on HCSDI and its components. The results of econometric analysis revealed a negative multiplier effect: an increase in the corruption of the socio-economic system of the state by 1% caused HCSDI reduce by more than 1%. The results and conclusions may be proxy-assessments of the socio-economic consequences of violations of the stability of reproduction of human capital in the conditions of the growth of corruption in the country
Promiscuous mating in the harem-roosting fruit bat, Cynopterus sphinx.
Garg, Kritika M; Chattopadhyay, Balaji; Doss D, Paramanatha Swami; A K, Vinoth Kumar; Kandula, Sripathi; Ramakrishnan, Uma
2012-08-01
Observations on mating behaviours and strategies guide our understanding of mating systems and variance in reproductive success. However, the presence of cryptic strategies often results in situations where social mating system is not reflective of genetic mating system. We present such a study of the genetic mating system of a harem-forming bat Cynopterus sphinx where harems may not be true indicators of male reproductive success. This temporal study using data from six seasons on paternity reveals that social harem assemblages do not play a role in the mating system, and variance in male reproductive success is lower than expected assuming polygynous mating. Further, simulations reveal that the genetic mating system is statistically indistinguishable from promiscuity. Our results are in contrast to an earlier study that demonstrated high variance in male reproductive success. Although an outcome of behavioural mating patterns, standardized variance in male reproductive success (I(m)) affects the opportunity for sexual selection. To gain a better understanding of the evolutionary implications of promiscuity for mammals in general, we compared our estimates of I(m) and total opportunity for sexual selection (I(m) /I(f), where I(f) is standardized variance in female reproductive success) with those of other known promiscuous species. We observed a broad range of I(m) /I(f) values across known promiscuous species, indicating our poor understanding of the evolutionary implications of promiscuous mating. © 2012 Blackwell Publishing Ltd.
Safer childbirth: a rights-based approach.
Boama, Vincent; Arulkumaran, Sabaratnam
2009-08-01
The Millennium Development Goals (MDGs) set very high targets for women's reproductive health through reductions in maternal and infant mortality, among other things. Reductions in maternal mortality and morbidity can be achieved through various different approaches, such as the confidential review of maternal deaths, use of evidence-based treatments and interventions, using a health systems approach, use of information technology, global and regional partnerships, and making pregnancy safer through initiatives that increase the focus on human rights. A combination of these and other approaches can have a synergistic impact on reductions in maternal mortality. This paper highlights some of the current global efforts on safer pregnancy with a focus on reproductive rights. We encourage readers to do more in every corner of the world to advocate for women's reproductive rights and, in this way, we may achieve the MDGs by 2015.
Late injury of cancer therapy on the female reproductive tract
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grigsby, P.W.; Russell, A.; Bruner, D.
1995-03-30
The purpose of this article is to review the late effects of cancer therapy on the female reproductive tract. The anatomic sites detailed are the vulva, vagina, cervix, uterus, fallopian tubes, and ovaries. The available pathophysiology is discussed. Clinical syndromes are presented. Tolerance doses of irradiation for late effects are rarely presented in the literature and are reviewed where available. Management strategies for surgical, radiotherapeutic, and chemotherapeutic late effects are discussed. Endpoints for evaluation of therapeutic late effects have been formulated utilizing the symptons, objective, management, and analytic (SOMA) format. Late effects on the female reproductive tract from cancer therapymore » should be recognized and managed appropriately. A grading system for these effects is presented. Endpoints for late effects and tolls for the evaluation need to be further developed. 61 refs., 9 figs., 13 tabs.« less
Marijuana, the Endocannabinoid System and the Female Reproductive System
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 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. PMID:27354844
Haslegrave, Marianne
2014-11-01
Since the International Conference on Population and Development (ICPD) in Cairo in 1994 there have been significant achievements in moving towards the goal of sexual and reproductive health and rights. Yet there have also been disappointments, as demonstrated in the Millennium Development Goals, even though in 2007 a target on reproductive health was added. Most recently, the 20-year review of the implementation of the ICPD Programme of Action, ICPD Beyond 2014, has taken place, which has moved forward the sexual and reproductive health and rights agenda. But, the main arena for future negotiations has changed and the UN is in the process of negotiating the post-2015 development agenda and the sustainable development goals (SDGs). This paper assesses what has been taking place since 2013 and provides information as to how the process for the post-2015 development agenda and the SDGs are likely to move forward. An understanding of what has been achieved, the processes as they are now proceeding and their future development are important for moving towards the ultimate goal of achieving sexual and reproductive health and rights in the next 15 years. Copyright © 2014 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
Waller, Diane L.; Luoma, James A.
2017-01-01
The biopesticide, Zequanox®, is registered for dreissenid mussel control in open water systems in the United States. Previous toxicity trials with nontarget organisms, including several young-of-the-year fish species and invertebrates, demonstrated selectivity of Zequanox for dreissenid mussels, but data are lacking on the treatment-related effects on reproduction and early life stage development of fish. The present study evaluated the effects of Zequanox on spawning and early life stages of the fathead minnow, Pimephales promelas, after exposure to the maximum approved concentration [100 mg active ingredient (AI)/L] and exposure duration (8h) for open water application. The results showed no significant treatment-related effect of Zequanox on survival, condition, or cumulative egg production (21 d) in adult fathead minnow. Eggs (≤24 h old) exposed to Zequanox developed to the eyed-stage at a similar rate to that of untreated eggs. Additionally, Zequanox did not have a significant effect on survival and growth (90 d) of newly hatched larvae (≤24-h old). Zequanox may be an option for control of dreissenid mussels in localized open water habitats where concerns exist regarding reproduction and recruitment of cyprinids and related species.
Mate choice, sexual selection, and endocrine-disrupting chemicals.
Gore, Andrea C; Holley, Amanda M; Crews, David
2018-05-01
Humans have disproportionately affected the habitat and survival of species through environmental contamination. Important among these anthropogenic influences is the proliferation of organic chemicals, some of which perturb hormone systems, the latter referred to as endocrine-disrupting chemicals (EDCs). EDCs are widespread in the environment and affect all levels of reproduction, including development of reproductive organs, hormone release and regulation through the life cycle, the development of secondary sexual characteristics, and the maturation and maintenance of adult physiology and behavior. However, what is not well-known is how the confluence of EDC actions on the manifestation of morphological and behavioral sexual traits influences mate choice, a process that requires the reciprocal evaluation of and/or acceptance of a sexual partner. Moreover, the outcomes of EDC-induced perturbations are likely to influence sexual selection; yet this has rarely been directly tested. Here, we provide background on the development and manifestation of sexual traits, reproductive competence, and the neurobiology of sexual behavior, and evidence for their perturbation by EDCs. Selection acts on individuals, with the consequences manifest in populations, and we discuss the implications for EDC contamination of these processes, and the future of species. Copyright © 2017 Elsevier Inc. All rights reserved.
Rivillas, Juan Carlos; Devia Rodriguez, Raul; Song, Gloria; Martel, Andréanne
2018-01-01
Objectives This paper assesses inequalities in access to reproductive and maternal health services among females affected by forced displacement and sexual and gender-based violence in conflict settings in Colombia. This was accomplished through the following approaches: first, we assessed the gaps and gradients in three selected reproductive and maternal health care services. Second, we analyzed the patterns of inequalities in reproductive and maternal health care services and changes over time. And finally, we identified challenges and strategies for reaching girls and women who are the hardest to reach in conflict settings, in order to accelerate progress towards universal health coverage and to contribute to meeting the Sustainable Development Goals of good health and well-being and gender equality by 2030. Methods Three types of data were required: data about health outcomes (relating to rates of females affected by conflict), information about reproductive and maternal health care services to provide a social dimension to unmask inequalities (unmet needs in family planning, antenatal care and skilled births attendance); and data on the female population. Data sources used include the National Information System for Social Protection, the National Registry of Victims, the National Administrative Department of Statistics, and Demographic Health Survey at three specific time points: 2005, 2010 and 2015. We estimated the slope index of inequality to express absolute inequality (gaps) and the concentration index to expresses relative inequality (gradients), and to understand whether inequality was eliminated over time. Results Our findings show that even though absolute health care service-related inequalities dropped over time, relative inequalities worsened or remain unchanged. All summary measures still indicated the existence of inequalities as well as common patterns. Our findings suggest that there is a pattern of marginal exclusion and incremental patterns of inequality in the reproductive and maternal health care service provided to female affected by armed conflict. Conclusions Overall, the effects of conflict continue to threaten reproductive and maternal health in Colombia, impeding progress towards the realization of universal health care (UHC) and reinforcing already-existing inequities. Key messages and steps forward include the need to understand the two distinct patterns of inequalities identified in this study in order to prompt improved general policy responses. Addressing unmet needs in reproductive and maternal health requires supporting gender equality and prioritizing the girls and women in regions with the highest rates of victims of armed conflict, with the objective of leaving no girl or woman behind. This analysis represents the first attempt to analyze coverage-related inequality in reproductive and maternal health care services for female affected by armed conflict in Colombia. As the World Health Organization and global health systems leaders call for more inclusive engagement, this approach may serve as the key to shaping people-centred health systems. In this particular case, health care facilities must be located in close proximity to girls and women in conflict and post-conflict settings in order to deliver essential reproductive and maternal health care services. Finally, reducing inequalities in opportunities would not only promote equity, but also drive sustainable development. PMID:29346375
78 FR 18629 - Notice of Lodging of Proposed Partial Consent Decree Under the Clean Water Act
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-27
... sewer system, perform initial work over the next four years to address sewer overflows, develop a..., DC 20044- 7611. Please enclose a check or money order for $84.50 (25 cents per page reproduction cost...
KANEKO-ISHINO, Tomoko; ISHINO, Fumitoshi
2015-01-01
Mammals, including human beings, have evolved a unique viviparous reproductive system and a highly developed central nervous system. How did these unique characteristics emerge in mammalian evolution, and what kinds of changes did occur in the mammalian genomes as evolution proceeded? A key conceptual term in approaching these issues is “mammalian-specific genomic functions”, a concept covering both mammalian-specific epigenetics and genetics. Genomic imprinting and LTR retrotransposon-derived genes are reviewed as the representative, mammalian-specific genomic functions that are essential not only for the current mammalian developmental system, but also mammalian evolution itself. First, the essential roles of genomic imprinting in mammalian development, especially related to viviparous reproduction via placental function, as well as the emergence of genomic imprinting in mammalian evolution, are discussed. Second, we introduce the novel concept of “mammalian-specific traits generated by mammalian-specific genes from LTR retrotransposons”, based on the finding that LTR retrotransposons served as a critical driving force in the mammalian evolution via generating mammalian-specific genes. PMID:26666304
Kaneko-Ishino, Tomoko; Ishino, Fumitoshi
2015-01-01
Mammals, including human beings, have evolved a unique viviparous reproductive system and a highly developed central nervous system. How did these unique characteristics emerge in mammalian evolution, and what kinds of changes did occur in the mammalian genomes as evolution proceeded? A key conceptual term in approaching these issues is "mammalian-specific genomic functions", a concept covering both mammalian-specific epigenetics and genetics. Genomic imprinting and LTR retrotransposon-derived genes are reviewed as the representative, mammalian-specific genomic functions that are essential not only for the current mammalian developmental system, but also mammalian evolution itself. First, the essential roles of genomic imprinting in mammalian development, especially related to viviparous reproduction via placental function, as well as the emergence of genomic imprinting in mammalian evolution, are discussed. Second, we introduce the novel concept of "mammalian-specific traits generated by mammalian-specific genes from LTR retrotransposons", based on the finding that LTR retrotransposons served as a critical driving force in the mammalian evolution via generating mammalian-specific genes.
Tricoire-Leignel, Hélène; Thany, Steeve Hervé; Gadenne, Christophe; Anton, Sylvia
2012-01-01
Most animals, including pest insects, live in an "odor world" and depend strongly on chemical stimuli to get information on their biotic and abiotic environment. Although integrated pest management strategies including the use of insect growth regulators (IGRs) are increasingly developed, most insect pest treatments rely on neurotoxic chemicals. These molecules are known to disrupt synaptic transmission, affecting therefore sensory systems. The wide-spread use of neurotoxic insecticides and the growing use of IGRs result in residual accumulation of low concentrations in the environment. These insecticide residues could act as an "info-disruptor" by modifying the chemical communication system, and therefore decrease chances of reproduction in target insects. However, residues can also induce a non-expected hormesis effect by enhancing reproduction abilities. Low insecticide doses might thus induce adaptive processes in the olfactory pathway of target insects, favoring the development of resistance. The effect of sublethal doses of insecticides has mainly been studied in beneficial insects such as honeybees. We review here what is known on the effects of sublethal doses of insecticides on the olfactory system of insect pests.
ASPECTS OF BASIC REPRODUCTIVE BIOLOGY AND ENDOCRINOLOGY IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS)
The fathead minnow has been proposed as a model species for assessing the adverse effects of endocrine-disrupting chemicals (EDCs) on reproduction and development. The purpose of these studies was to develop baseline reproductive biology and endocrinology data for this species to...
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GnRH in the Human Female Reproductive Axis.
Limonta, Patrizia; Marelli, Marina Montagnani; Moretti, Roberta; Marzagalli, Monica; Fontana, Fabrizio; Maggi, Roberto
2018-01-01
Gonadotropin-releasing hormone (GnRH) is recognized as the central regulator of the functions of the pituitary-gonadal axis. The increasing knowledge on the mechanisms controlling the development and the function of GnRH-producing neurons is leading to a better diagnostic and therapeutic approach for hypogonadotropic hypogonadisms and for alterations of the puberty onset. During female life span, the function of the GnRH pulse generator may be affected by a number of inputs from other neuronal systems, offering alternative strategies for diagnostic and therapeutic interventions. Moreover, the identification of a GnRH/GnRH receptor system in both human ovary and endometrium has widened the spectrum of action of the peptide outside its hypothalamic functions. The pharmacological use of GnRH itself or its synthetic analogs (agonists and antagonists) provides a valid tool to either stimulate or block gonadotropin secretion and to modulate the female fertility in several reproductive disorders and in assisted reproduction technology. The use of GnRH agonists in young female patients undergoing chemotherapy is also considered a promising therapeutic approach to counteract iatrogenic ovarian failure. © 2018 Elsevier Inc. All rights reserved.
Hogan, Lindsay A; Janssen, Tina; Johnston, Stephen D
2013-06-01
This review provides an update on what is currently known about wombat reproductive biology and reports on attempts made to manipulate and/or enhance wombat reproduction as part of the development of artificial reproductive technology (ART) in this taxon. Over the last decade, the logistical difficulties associated with monitoring a nocturnal and semi-fossorial species have largely been overcome, enabling new features of wombat physiology and behaviour to be elucidated. Despite this progress, captive propagation rates are still poor and there are areas of wombat reproductive biology that still require attention, e.g. further characterisation of the oestrous cycle and oestrus. Numerous advances in the use of ART have also been recently developed in the Vombatidae but despite this research, practical methods of manipulating wombat reproduction for the purposes of obtaining research material or for artificial breeding are not yet available. Improvement of the propagation, genetic diversity and management of wombat populations requires a thorough understanding of Vombatidae reproduction. While semen collection and cryopreservation in wombats is fairly straightforward there is currently an inability to detect, induce or synchronise oestrus/ovulation and this is an impeding progress in the development of artificial insemination in this taxon.
Reproductive traits affect the rescue of valuable and endangered multipurpose tropical trees
Sinébou, Viviane; Quinet, Muriel; Ahohuendo, Bonaventure C.; Jacquemart, Anne-Laure
2016-01-01
Conservation strategies are urgently needed in Tropical areas for widely used tree species. Increasing numbers of species are threatened by overexploitation and their recovery might be poor due to low reproductive success and poor regeneration rates. One of the first steps in developing any conservation policy should be an assessment of the reproductive biology of species that are threatened by overexploitation. This work aimed to study the flowering biology, pollination and breeding system of V. doniana, a multipurpose threatened African tree, as one step in assessing the development of successful conservation strategies. To this end, we studied (1) traits directly involved in pollinator attraction like flowering phenology, flower numbers and morphology, and floral rewards; (2) abundance, diversity and efficiency of flower visitors; (3) breeding system, through controlled hand-pollination experiments involving exclusion of pollinators and pollen from different sources; and (4) optimal conditions for seed germination. The flowering phenology was asynchronous among inflorescences, trees and sites. The flowers produced a large quantity of pollen and nectar with high sugar content. Flowers attracted diverse and abundant visitors, counting both insects and birds, and efficient pollinators included several Hymenoptera species. We detected no spontaneous self-pollination, indicating a total dependence on pollen vectors. Vitex doniana is self-compatible and no inbreeding depression occurred in the first developmental stages. After extraction of the seed from the fruit, seed germination did not require any particular conditions or pre-treatments and the seeds showed high germination rates. These pollination and breeding characteristics as well as germination potential offer the required conditions to develop successful conservation strategies. Protection, cultivation and integration in agroforestry systems are required to improve the regeneration of the tree. PMID:27354660
Reproductive traits affect the rescue of valuable and endangered multipurpose tropical trees.
Sinébou, Viviane; Quinet, Muriel; Ahohuendo, Bonaventure C; Jacquemart, Anne-Laure
2016-01-01
Conservation strategies are urgently needed in Tropical areas for widely used tree species. Increasing numbers of species are threatened by overexploitation and their recovery might be poor due to low reproductive success and poor regeneration rates. One of the first steps in developing any conservation policy should be an assessment of the reproductive biology of species that are threatened by overexploitation. This work aimed to study the flowering biology, pollination and breeding system of V. doniana, a multipurpose threatened African tree, as one step in assessing the development of successful conservation strategies. To this end, we studied (1) traits directly involved in pollinator attraction like flowering phenology, flower numbers and morphology, and floral rewards; (2) abundance, diversity and efficiency of flower visitors; (3) breeding system, through controlled hand-pollination experiments involving exclusion of pollinators and pollen from different sources; and (4) optimal conditions for seed germination. The flowering phenology was asynchronous among inflorescences, trees and sites. The flowers produced a large quantity of pollen and nectar with high sugar content. Flowers attracted diverse and abundant visitors, counting both insects and birds, and efficient pollinators included several Hymenoptera species. We detected no spontaneous self-pollination, indicating a total dependence on pollen vectors. Vitex doniana is self-compatible and no inbreeding depression occurred in the first developmental stages. After extraction of the seed from the fruit, seed germination did not require any particular conditions or pre-treatments and the seeds showed high germination rates. These pollination and breeding characteristics as well as germination potential offer the required conditions to develop successful conservation strategies. Protection, cultivation and integration in agroforestry systems are required to improve the regeneration of the tree. Published by Oxford University Press on behalf of the Annals of Botany Company.
Multiple births associated with assisted human reproduction in Canada.
Cook, Jocelynn L; Geran, Leslie; Rotermann, Michelle
2011-06-01
Assisted human reproduction has been associated with increased rates of multiple births. Data suggest that twins and higher order multiple pregnancies are at risk for pre- and postnatal health complications that contribute to stress on both the family and the Canadian health care system. No published Canadian data estimate the contribution of assisted human reproduction to multiple birth rates. This study was designed to determine the contributions of age and assisted human reproduction to multiple birth rates in Canada. We performed analyses of existing Canadian databases, using a mathematical model from the Centers for Disease Control and Prevention. More specifically, data from the Canadian Vital Statistics: Births and Stillbirths database were combined with data from the Canadian Assisted Reproductive Technologies Register collected by the Canadian Fertility and Andrology Society. Datasets were standardized to age distributions of mothers in 1978. RESULTS suggest that in vitro fertilization, ovulation induction, and age each contribute more to the rates of triplets than to twins. As expected, the contribution of natural factors was higher to twins than to triplets. These are the first Canadian data analyzed to separate and measure the contributions of age and assisted reproductive technologies to multiple birth rates. Our findings are important for guiding physician and patient education and informing the development of treatment protocols that will result in lower-risk pregnancies and improved long-term health for women and their offspring.
Molecular characterization of the human microbiome from a reproductive perspective.
Mor, Amir; Driggers, Paul H; Segars, James H
2015-12-01
The process of reproduction inherently poses unique microbial challenges because it requires the transfer of gametes from one individual to the other, meanwhile preserving the integrity of the gametes and individuals from harmful microbes during the process. Advances in molecular biology techniques have expanded our understanding of the natural organisms living on and in our bodies, including those inhabiting the reproductive tract. Over the past two decades accumulating evidence has shown that the human microbiome is tightly related to health and disease states involving the different body systems, including the reproductive system. Here we introduce the science involved in the study of the human microbiome. We examine common methods currently used to characterize the human microbiome as an inseparable part of the reproductive system. Finally, we consider a few limitations, clinical implications, and the critical need for additional research in the field of human fertility. Copyright © 2015. Published by Elsevier Inc.
Torretta, Juan Pablo; Basilio, Alicia M
2009-01-01
The "talares" in eastern Buenos Aires province, Argentina, are coastal xerophitic forests structured by few arboreal species surrounded by a lower and moister soil matrix. We studied the reproductive parameters of the most representative arboreal species (Celtis tala, Scutia buxifolia, Jodina rhombifolia, and Schinus longifolia). Pollen dispersion was studied through floral visitor traps (biotic dispersion) and using gravimetric pollen collectors (abiotic dispersion). The reproductive success (fruit formation rate) of the focal species was studied by enclosing flowers with different mesh bags. The reproductive system varied among the different species. C. tala was anemophilous and selfcompatible. S. buxifolia was entomophilous and floral visitors dependant. J. rhombifolia was entomophylous, although spontaneous autogamy could favor reproduction in the absence of pollinators. Lastly, S. longifolia could be an ambophilous species (pollinated by insects and by the wind). This dual system may be the result of system flexibility mechanism or an evolutionary transition.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 42 Public Health 1 2012-10-01 2012-10-01 false Reproduction. 9.7 Section 9.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS STANDARDS OF CARE FOR CHIMPANZEES HELD IN THE FEDERALLY SUPPORTED SANCTUARY SYSTEM § 9.7 Reproduction. Chimpanzee reproduction is prohibited in the sanctuary. Therefore, all...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 42 Public Health 1 2014-10-01 2014-10-01 false Reproduction. 9.7 Section 9.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS STANDARDS OF CARE FOR CHIMPANZEES HELD IN THE FEDERALLY SUPPORTED SANCTUARY SYSTEM § 9.7 Reproduction. Chimpanzee reproduction is prohibited in the sanctuary. Therefore, all...
Code of Federal Regulations, 2013 CFR
2013-10-01
... 42 Public Health 1 2013-10-01 2013-10-01 false Reproduction. 9.7 Section 9.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS STANDARDS OF CARE FOR CHIMPANZEES HELD IN THE FEDERALLY SUPPORTED SANCTUARY SYSTEM § 9.7 Reproduction. Chimpanzee reproduction is prohibited in the sanctuary. Therefore, all...
Effect of TiO2 nanoparticles on the reproduction of silkworm.
Ni, Min; Li, Fanchi; Wang, Binbin; Xu, Kaizun; Zhang, Hua; Hu, Jingsheng; Tian, Jianghai; Shen, Weide; Li, Bing
2015-03-01
Silkworm (Bombyx mori) is an important economic insect and the model insect of Lepidoptera. Because of its high fecundity and short reproduction cycle, it has been widely used in reproduction and development research. The high concentrations of titanium dioxide nanoparticles (TiO2 NPs) show reproductive toxicity, while low concentrations of TiO2 NPs have been used as feed additive and demonstrated significant biological activities. However, whether the low concentrations of TiO2 NPs affect the reproduction of B. mori has not been reported. In this study, the growth and development of gonad of B. mori fed with a low concentration of TiO2 NPs (5 mg/L) were investigated by assessing egg production and expression of reproduction-related genes. The results showed that the low concentration of TiO2 NPs resulted in faster development of the ovaries and testes and more gamete differentiation and formation, with an average increase of 51 eggs per insect and 0.34 × 10(-4) g per egg after the feeding. The expressions of several reproduction-related genes were upregulated, such as the yolk-development-related genes Ovo-781 and vitellogenin (Vg) were increased by 5.33- and 6.77-folds, respectively. This study shows that TiO2 NPs feeding at low concentration can enhance the reproduction of B. mori, and these results are useful in developing new methods to improve fecundity in B. mori and providing new clues for its broad biological applications.
Phenology, dichogamy, and floral synchronization in a northern red oak (Quercus rubra) seed orchard
Lisa W. Alexander; Keith E. Woeste
2016-01-01
We developed a novel scoring system to assess spring phenology in a northern red oak (Quercus rubra L.) clonal seed orchard. The system was used to score from 304 to 364 ramets for three reproductive seasons and to place clones into early, intermediate, and late phenology classes. Although the absolute number of clones in each phenological class...
Bone Morphogenetic Protein (BMP) signaling in animal reproductive system development and function.
Lochab, Amaneet K; Extavour, Cassandra G
2017-07-15
In multicellular organisms, the specification, maintenance, and transmission of the germ cell lineage to subsequent generations are critical processes that ensure species survival. A number of studies suggest that the Bone Morphogenetic Protein (BMP) pathway plays multiple roles in this cell lineage. We wished to use a comparative framework to examine the role of BMP signaling in regulating these processes, to determine if patterns would emerge that might shed light on the evolution of molecular mechanisms that may play germ cell-specific or other reproductive roles across species. To this end, here we review evidence to date from the literature supporting a role for BMP signaling in reproductive processes across Metazoa. We focus on germ line-specific processes, and separately consider somatic reproductive processes. We find that from primordial germ cell (PGC) induction to maintenance of PGC identity and gametogenesis, BMP signaling regulates these processes throughout embryonic development and adult life in multiple deuterostome and protostome clades. In well-studied model organisms, functional genetic evidence suggests that BMP signaling is required in the germ line across all life stages, with the exception of PGC specification in species that do not use inductive signaling to induce germ cell formation. The current evidence is consistent with the hypothesis that BMP signaling is ancestral in bilaterian inductive PGC specification. While BMP4 appears to be the most broadly employed ligand for the reproductive processes considered herein, we also noted evidence for sex-specific usage of different BMP ligands. In gametogenesis, BMP6 and BMP15 seem to have roles restricted to oogenesis, while BMP8 is restricted to spermatogenesis. We hypothesize that a BMP-based mechanism may have been recruited early in metazoan evolution to specify the germ line, and was subsequently co-opted for use in other germ line-specific and somatic reproductive processes. We suggest that if future studies assessing the function of the BMP pathway across extant species were to include a reproductive focus, that we would be likely to find continued evidence in favor of an ancient association between BMP signaling and the reproductive cell lineage in animals. Copyright © 2017 Elsevier Inc. All rights reserved.
Durán-Medina, Yolanda; Serwatowska, Joanna; Reyes-Olalde, J Irepan; de Folter, Stefan; Marsch-Martínez, Nayelli
2017-01-01
The gynoecium is the female reproductive system in flowering plants. It is a complex structure formed by different tissues, some that are essential for reproduction and others that facilitate the fertilization process and nurture and protect the developing seeds. The coordinated development of these different tissues during the formation of the gynoecium is important for reproductive success. Both hormones and genetic regulators guide the development of the different tissues. Auxin and cytokinin in particular have been found to play important roles in this process. On the other hand, the AP2/ERF2 transcription factor BOL/DRNL/ESR2/SOB is expressed at very early stages of aerial organ formation and has been proposed to be a marker for organ founder cells. In this work, we found that this gene is also expressed at later stages during gynoecium development, particularly at the lateral regions (the region related to the valves of the ovary). The loss of DRNL function affects gynoecium development. Some of the mutant phenotypes present similarities to those observed in plants treated with exogenous cytokinins, and AHP6 has been previously proposed to be a target of DRNL. Therefore, we explored the response of drnl-2 developing gynoecia to cytokinins, and found that the loss of DRNL function affects the response of the gynoecium to exogenously applied cytokinins in a developmental-stage-dependent manner. In summary, this gene participates during gynoecium development, possibly through the dynamic modulation of cytokinin homeostasis and response.
Durán-Medina, Yolanda; Serwatowska, Joanna; Reyes-Olalde, J. Irepan; de Folter, Stefan; Marsch-Martínez, Nayelli
2017-01-01
The gynoecium is the female reproductive system in flowering plants. It is a complex structure formed by different tissues, some that are essential for reproduction and others that facilitate the fertilization process and nurture and protect the developing seeds. The coordinated development of these different tissues during the formation of the gynoecium is important for reproductive success. Both hormones and genetic regulators guide the development of the different tissues. Auxin and cytokinin in particular have been found to play important roles in this process. On the other hand, the AP2/ERF2 transcription factor BOL/DRNL/ESR2/SOB is expressed at very early stages of aerial organ formation and has been proposed to be a marker for organ founder cells. In this work, we found that this gene is also expressed at later stages during gynoecium development, particularly at the lateral regions (the region related to the valves of the ovary). The loss of DRNL function affects gynoecium development. Some of the mutant phenotypes present similarities to those observed in plants treated with exogenous cytokinins, and AHP6 has been previously proposed to be a target of DRNL. Therefore, we explored the response of drnl-2 developing gynoecia to cytokinins, and found that the loss of DRNL function affects the response of the gynoecium to exogenously applied cytokinins in a developmental-stage-dependent manner. In summary, this gene participates during gynoecium development, possibly through the dynamic modulation of cytokinin homeostasis and response. PMID:29123539
Women, war, and reproductive health in developing countries.
Pillai, Vijayan; Wang, Ya-Chien; Maleku, Arati
2017-01-01
Globally, millions of people are affected by war and conflicts every year. However, women have increasingly suffered the greatest harm by war in more different ways than men. We conceptualize a reproductive rights approach toward examining the effects of war on women's reproductive health in developing countries. Given the rising concerns of exclusion to adequately address women's rights, sexual and gender-based violence, and post-conflict accountability, we specifically focus on the limitations of the Minimum Initial Service Package, a UN-sponsored reproductive health service program in conflict zones while offering a broad reproductive rights-based conceptual lens for examining reproductive health care services in war-torn areas. In addition, we discuss the roles social workers may play at both micro and macro levels in war-torn areas to bring about both short term and long term gains in women's reproductive health.
1997-08-01
AL/EQ-TR-1997-0050 DEVELOPMENT AND EVALUATION OF REPRODUCTIVE AND DEVELOPMENT TOXICITY TESTS FOR ASSESSING THE HAZARDS OF ENVIRONMENTAL...SUBTITLE Development and Evaluation of Reproductive and Developmental Toxicity Tests for Assessing the Hazards of Environmental Contaminants 6...pd in testing toxicity in surface waters, ground waters and H- ™t™j£J^^^M hazard assessment when used in conjunction in sediments. FETAX can be usea
Role of pigment epithelium-derived factor in the reproductive system.
Chuderland, Dana; Ben-Ami, Ido; Bar-Joseph, Hadas; Shalgi, Ruth
2014-10-01
The physiological function of the female reproductive organs is hormonally controlled. In each cycle, the reproductive organs undergo tissue modifications that are accompanied by formation and destruction of blood vessels. Proper angiogenesis requires an accurate balance between stimulatory and inhibitory signals, provided by pro- and anti-angiogenic factors. As with many other tissues, vascular endothelial growth factor (VEGF) appears to be one of the major pro-angiogenic factors in the female reproductive organs. Pigment epithelium-derived factor (PEDF) is a non-inhibitory member of the serine protease inhibitors (serpin) superfamily, possessing potent physiologic anti-angiogenic activity that negates VEGF activity. The role of PEDF in decreasing abnormal neovascularization by exerting its anti-angiogenic effect that inhibits pro-angiogenic factors, including VEGF, has been investigated mainly in the eye and in cancer. This review summarizes the function of PEDF in the reproductive system, showing its hormonal regulation and its anti-angiogenic activity. Furthermore, some pathologies of the female reproductive organs, including endometriosis, ovarian hyperstimulation syndrome, polycystic ovary syndrome, and others, are associated with a faulty angiogenic process. This review illuminates the role of PEDF in their pathogenesis and treatment. Collectively, we can conclude that although PEDF seems to play an essential role in the physiology and pathophysiology of the reproductive system, its full role and mechanism of action still need to be elucidated. © 2014 Society for Reproduction and Fertility.
Maciel-Silva, Adaíses S.; Marques Valio, Ivany F.; Rydin, Håkan
2012-01-01
Background and aims Short life cycles and trade-offs linked to breeding systems make bryophytes good models for the study of plant reproductive strategies. Our aim was to test if differences in sexual reproductive performance of bryophytes in tropical rainforests are driven by the breeding system of the species (monoicous or dioicous) or are mainly affected by the habitat. Methodology The reproductive performance (sexual branches, gametangia (sex organs), fertilization and sporophyte production) of 11 species was repeatedly monitored and analysed from populations at sea-level and montane sites of a Brazilian Atlantic rainforest over 15 months. Principal results Monoicous species had the highest reproductive performance, particularly for sexual branches, fertilized gametangia and sporophyte production. Species at the sea-level site produced more sexual branches and had more female-biased sex ratios of gametangia than species in the montane site. Fertilizations were more frequent at the montane site, but sporophyte frequency was similar between the two sites. Fertilization tended to occur mostly in the periods of heavy rain (October to December). Conclusions Breeding system is not the only major influence on the reproductive performance of bryophytes. We show that habitat is also an important factor determining life-history differentiation. Female-biased sex ratios and low rates of fertilization are seen to be compensated for by high production of reproductive structures at the initial phases of the reproductive cycle. PMID:22822422
Involvement of the avian song system in reproductive behaviour
Wild, J. Martin; Botelho, João F.
2015-01-01
The song system of songbirds consists of an interconnected set of forebrain nuclei that has traditionally been regarded as dedicated to the learning and production of song. Here, however, we suggest that the song system could also influence muscles used in reproductive behaviour, such as the cloacal sphincter muscle. We show that the same medullary nucleus, retroambigualis (RAm), that projects upon spinal motoneurons innervating expiratory muscles (which provide the pressure head for vocalization) and upon vocal motoneurons for respiratory–vocal coordination also projects upon cloacal motoneurons. Furthermore, RAm neurons projecting to sacral spinal levels were shown to receive direct projections from nucleus robustus arcopallialis (RA) of the forebrain song system. Thus, by indicating a possible disynaptic relationship between RA and motoneurons innervating the reproductive organ, in both males and females, these results potentially extend the role of the song system to include consummatory as well as appetitive aspects of reproductive behaviour. PMID:26631245
Opportunities and questions for the fundamental biological sciences in space
NASA Technical Reports Server (NTRS)
Sharp, Joseph C.; Vernikos, Joan
1992-01-01
The nature of biological issues which can be addressed during long-term space missions is briefly discussed. These issues include structure, from cell to organ to organism; function, the regulation of systems such as immunology, neural sciences, and behavior; and reproduction and development.
The vertebrate hypothalamic-pituitary-gonadal (HPG) axis is a highly dynamic system, which, through various feedback mechanisms, strives to maintain physiological conditions conducive to reproduction even in potentially stressful situations. The development of useful predictive m...
Genetic Circuits that Govern Bisexual and Unisexual Reproduction in Cryptococcus neoformans
Feretzaki, Marianna; Heitman, Joseph
2013-01-01
Cryptococcus neoformans is a human fungal pathogen with a defined sexual cycle. Nutrient-limiting conditions and pheromones induce a dimorphic transition from unicellular yeast to multicellular hyphae and the production of infectious spores. Sexual reproduction involves cells of either opposite (bisexual) or one (unisexual) mating type. Bisexual and unisexual reproduction are governed by shared components of the conserved pheromone-sensing Cpk1 MAPK signal transduction cascade and by Mat2, the major transcriptional regulator of the pathway. However, the downstream targets of the pathway are largely unknown, and homology-based approaches have failed to yield downstream transcriptional regulators or other targets. In this study, we applied insertional mutagenesis via Agrobacterium tumefaciens transkingdom DNA delivery to identify mutants with unisexual reproduction defects. In addition to elements known to be involved in sexual development (Crg1, Ste7, Mat2, and Znf2), three key regulators of sexual development were identified by our screen: Znf3, Spo11, and Ubc5. Spo11 and Ubc5 promote sporulation during both bisexual and unisexual reproduction. Genetic and phenotypic analyses provide further evidence implicating both genes in the regulation of meiosis. Phenotypic analysis of sexual development showed that Znf3 is required for hyphal development during unisexual reproduction and also plays a central role during bisexual reproduction. Znf3 promotes cell fusion and pheromone production through a pathway parallel to and independent of the pheromone signaling cascade. Surprisingly, Znf3 participates in transposon silencing during unisexual reproduction and may serve as a link between RNAi silencing and sexual development. Our studies illustrate the power of unbiased genetic screens to reveal both novel and conserved circuits that operate sexual reproduction. PMID:23966871
Genetic circuits that govern bisexual and unisexual reproduction in Cryptococcus neoformans.
Feretzaki, Marianna; Heitman, Joseph
2013-01-01
Cryptococcus neoformans is a human fungal pathogen with a defined sexual cycle. Nutrient-limiting conditions and pheromones induce a dimorphic transition from unicellular yeast to multicellular hyphae and the production of infectious spores. Sexual reproduction involves cells of either opposite (bisexual) or one (unisexual) mating type. Bisexual and unisexual reproduction are governed by shared components of the conserved pheromone-sensing Cpk1 MAPK signal transduction cascade and by Mat2, the major transcriptional regulator of the pathway. However, the downstream targets of the pathway are largely unknown, and homology-based approaches have failed to yield downstream transcriptional regulators or other targets. In this study, we applied insertional mutagenesis via Agrobacterium tumefaciens transkingdom DNA delivery to identify mutants with unisexual reproduction defects. In addition to elements known to be involved in sexual development (Crg1, Ste7, Mat2, and Znf2), three key regulators of sexual development were identified by our screen: Znf3, Spo11, and Ubc5. Spo11 and Ubc5 promote sporulation during both bisexual and unisexual reproduction. Genetic and phenotypic analyses provide further evidence implicating both genes in the regulation of meiosis. Phenotypic analysis of sexual development showed that Znf3 is required for hyphal development during unisexual reproduction and also plays a central role during bisexual reproduction. Znf3 promotes cell fusion and pheromone production through a pathway parallel to and independent of the pheromone signaling cascade. Surprisingly, Znf3 participates in transposon silencing during unisexual reproduction and may serve as a link between RNAi silencing and sexual development. Our studies illustrate the power of unbiased genetic screens to reveal both novel and conserved circuits that operate sexual reproduction.
NASA Astrophysics Data System (ADS)
Yuniarti, E.; Fadilah, M.; Darussyamsu, R.; Nurhayati, N.
2018-04-01
The higher numbers of cases around sexual behavioral deviance on adolescence are significantly related to their knowledge level about the health of the reproduction system. Thus, teenagers, especially school-aged, have to receive the complete information which emphasizes on recognize promotion and prevention knowledge. This article aims to describe information about health promotion and prevention, which delivered by the teacher in Senior High School learning process on topic reproduction system. The data gained through focused observation using observation sheet and camera recorder. Further, data analyzed descriptively. The result show promotion and preventive approach have been inadequately presented. There are two reasons. Firstly, the promotion and preventive value are not technically requested in the final assessment. The second, the explanation tend to refer to consequences existed in the term of the social and religious norm rather than a scientific basis. It can be concluded suggestion to promote health reproduction and prevent the risk of health reproduction need to be implemented more practice with a scientific explanation which is included in a specific program for adolescence reproductive health improvement.
Sexual Hearing: The influence of sex hormones on acoustic communication in frogs
Arch, Victoria S.; Narins, Peter M.
2009-01-01
The majority of anuran amphibians (frogs and toads) use acoustic communication to mediate sexual behavior and reproduction. Generally, females find and select their mates using acoustic cues provided by males in the form of conspicuous advertisement calls. In these species, vocal signal production and reception are intimately tied to successful reproduction. Research with anurans has demonstrated that acoustic communication is modulated by reproductive hormones, including gonadal steroids and peptide neuromodulators. Most of these studies have focused on the ways in which hormonal systems influence vocal signal production; however, here we will concentrate on a growing body of literature that examines hormonal modulation of call reception. This literature suggests that reproductive hormones contribute to the coordination of reproductive behaviors between signaler and receiver by modulating sensitivity and spectral filtering of the anuran auditory system. It has become evident that the hormonal systems that influence reproductive behaviors are highly conserved among vertebrate taxa, thus studying the endocrine and neuromodulatory bases of acoustic communication in frogs and toads can lead to insights of broader applicability to hormonal modulation of vertebrate sensory physiology and behavior. PMID:19272318
Tang, Haipei; Liu, Yun; Luo, Daji; Ogawa, Satoshi; Yin, Yike; Li, Shuisheng; Zhang, Yong; Hu, Wei; Parhar, Ishwar S.; Lin, Haoran
2015-01-01
The kiss1/gpr54 signaling system is considered to be a critical regulator of reproduction in most vertebrates. However, this presumption has not been tested vigorously in nonmammalian vertebrates. Distinct from mammals, multiple kiss1/gpr54 paralogous genes (kiss/kissr) have been identified in nonmammalian vertebrates, raising the possibility of functional redundancy among these genes. In this study, we have systematically generated the zebrafish kiss1−/−, kiss2−/−, and kiss1−/−;kiss2−/− mutant lines as well as the kissr1−/−, kissr2−/−, and kissr1−/−;kissr2−/− mutant lines using transcription activator-like effector nucleases. We have demonstrated that spermatogenesis and folliculogenesis as well as reproductive capability are not impaired in all of these 6 mutant lines. Collectively, our results indicate that kiss/kissr signaling is not absolutely required for zebrafish reproduction, suggesting that the kiss/kissr systems play nonessential roles for reproduction in certain nonmammalian vertebrates. These findings also demonstrated that fish and mammals have evolved different strategies for neuroendocrine control of reproduction. PMID:25406015
Between a rock and a hard place: the question of money at St. Petersburg women's clinics.
Larivaara, Meri; Dubikaytis, Tatiana; Kuznetsova, Olga; Hemminki, Elina
2008-01-01
The new financing mechanisms introduced into the Russian health care system since the beginning of the 1990s have not resolved its severe financial problems. This article examines the consequences for outpatient services and the daily work of individual doctors in St. Petersburg, using women's reproductive health services as a case example. Interview and observational data reveal a constant opposition between formal rules and informal practices at both the administrative and polyclinic levels. Polyclinics for women's reproductive health services have developed various strategies as a response to insufficient financing, but many of these strategies are questionable within the current mandatory health insurance system. Ordinary doctors perceive the development as mainly negative. The results raise the question of increasing arbitrariness, from patients' perspective, in the health services provided. The study illustrates how in a post-socialist context, the past constantly permeates the present in the form of novel adaptations to the new social context.
Zhang, Shuang-Shuang; Yang, Hongxing; Ding, Lan; Song, Ze-Ting; Ma, Hong; Chang, Fang
2017-01-01
High temperatures have a great impact on plant reproductive development and subsequent fruit and seed set, but the underlying molecular mechanisms are not well understood. We used transcriptome profiling to investigate the effect of heat stress on reproductive development of Arabidopsis thaliana plants and observed distinct response patterns in vegetative versus reproductive tissues. Exposure to heat stress affected reproductive developmental programs, including early phases of anther/ovule development and meiosis. Also, genes participating in the unfolded protein response (UPR) were enriched in the reproductive tissue-specific genes that were upregulated by heat. Moreover, we found that the UPR-deficient bzip28 bzip60 double mutant was sensitive to heat stresses and had reduced silique length and fertility. Comparison of heat-responsive wild type versus bzip28 bzip60 plants identified 521 genes that were regulated by bZIP28 and bZIP60 upon heat stress during reproductive stages, most of which were noncanonical UPR genes. Chromatin immunoprecipitation coupled with high-throughput sequencing analyses revealed 133 likely direct targets of bZIP28 in Arabidopsis seedlings subjected to heat stress, including 27 genes that were also upregulated by heat during reproductive development. Our results provide important insights into heat responsiveness in Arabidopsis reproductive tissues and demonstrate the protective roles of the UPR for maintaining fertility upon heat stress. PMID:28442596
Phthalate esters and reproductive toxicity the presentation described the uses of phthalates, the toxicity to mammals with a focus on reproductive toxicity and the potency of these chemicals to disrupt mammalian reproductive development in utero
Dominoni, Davide M; Quetting, Michael; Partecke, Jesko
2013-01-01
Light pollution is known to affect important biological functions of wild animals, including daily and annual cycles. However, knowledge about long-term effects of chronic exposure to artificial light at night is still very limited. Here we present data on reproductive physiology, molt and locomotor activity during two-year cycles of European blackbirds (Turdus merula) exposed to either dark nights or 0.3 lux at night. As expected, control birds kept under dark nights exhibited two regular testicular and testosterone cycles during the two-year experiment. Control urban birds developed testes faster than their control rural conspecifics. Conversely, while in the first year blackbirds exposed to light at night showed a normal but earlier gonadal cycle compared to control birds, during the second year the reproductive system did not develop at all: both testicular size and testosterone concentration were at baseline levels in all birds. In addition, molt sequence in light-treated birds was more irregular than in control birds in both years. Analysis of locomotor activity showed that birds were still synchronized to the underlying light-dark cycle. We suggest that the lack of reproductive activity and irregular molt progression were possibly the results of i) birds being stuck in a photorefractory state and/or ii) chronic stress. Our data show that chronic low intensities of light at night can dramatically affect the reproductive system. Future studies are needed in order to investigate if and how urban animals avoid such negative impact and to elucidate the physiological mechanisms behind these profound long-term effects of artificial light at night. Finally we call for collaboration between scientists and policy makers to limit the impact of light pollution on animals and ecosystems.
Persson, Sara; Magnusson, Ulf
2015-02-01
The wild American mink, a semi-aquatic top predator, is exposed to high levels of environmental pollutants that may affect its reproductive system. In this study, the reproductive organs from 101 wild male mink collected in Sweden were examined during necropsy. Potential associations between various variables of the reproductive system and fat concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), dichlorodiphenyldichloroethylene (p,p'-DDE) and other organochlorine pesticides and liver concentrations of perfluoroalkyl acids (PFAAs) were investigated using multiple regression models. The anogenital distance was negatively associated (p<0.05) with concentration of p,p'-DDE and some PFAAs (perfluorooctane sulfonate (PFOS), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA) and ∑PFAA). Penis length was positively associated with PCB 28, PCB 47/48, PCB 52 and PCB 110 (p<0.05), and some of these congeners were also associated with baculum length and penis weight. In contrast, penile length tended (p<0.1) to be shorter in mink with high concentrations of p,p'-DDE. These data may help to improve the understanding of how environmental pollution affects male reproduction in both wildlife and humans. Overall, the study suggests endocrine disrupting effects in wild mink and identifies potentially important pollutants in the complex mixture of contaminants in the environment. In addition, the results suggest that the variables of the reproductive system of male mink used in this study are good candidates for use as indicators of environmental pollution affecting the mammalian reproductive system. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Abby E. Fuhrman; Donald A. Larsen; Ashley Steel; Graham Young; Brian R. Beckman
2017-01-01
Water temperature can have a profound influence on development and distribution of aquatic species. Salmon are particularly vulnerable to temperature changes because their reproductive and early development life phases are spent in freshwater river systems where temperature fluctuates widely both daily and seasonally. Flow regulation downstream of dams can also cause...
Analysis of Rhizome Development in Oryza longistaminata, a Wild Rice Species.
Yoshida, Akiko; Terada, Yasuhiko; Toriba, Taiyo; Kose, Katsumi; Ashikari, Motoyuki; Kyozuka, Junko
2016-10-01
Vegetative reproduction is a form of asexual propagation in plants. A wide range of plants develop rhizomes, modified stems that grow underground horizontally, as a means of vegetative reproduction. In rhizomatous species, despite their distinct developmental patterns, both rhizomes and aerial shoots derive from axillary buds. Therefore, it is of interest to understand the basis of rhizome initiation and development. Oryza longistaminata, a wild rice species, develops rhizomes. We analyzed bud initiation and growth of O. longistaminata rhizomes using various methods of morphological observation. We show that, unlike aerial shoot buds that contain a few leaves only, rhizome buds initiate several leaves and bend to grow at right angles to the original rhizome. Rhizomes are maintained in the juvenile phase irrespective of the developmental phase of the aerial shoot. Stem elongation and reproductive transition are tightly linked in the aerial shoots, but are uncoupled in the rhizome. Our findings indicate that developmental programs operate independently in the rhizomes and aerial shoots. Temporal modification of the developmental pathways that are common to rhizomes and aerial shoots may be the source of developmental plasticity. Furthermore, the creation of new developmental systems appears to be necessary for rhizome development. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Management of pre-pubertal small ruminants: physiological basis and clinical approach.
Valasi, I; Chadio, S; Fthenakis, G C; Amiridis, G S
2012-02-01
Puberty is a gradual process, during which animal reproductive competence is attained with respect to physiology, morphology and behaviour. Onset of puberty in small ruminants differs between sexes, due to early sexual differentiation in the control of steroid feedback systems and, thus, GnRH secretion. A number of puberty determinants have been identified, which include genetic factors, as well as endogenous signals, such as energy balance and environmental cues, whose dynamic interplay is responsible for the timing of puberty onset. Puberty timing affects reproduction through age at first lambing, which impacts on subsequent reproductive life and productivity of small ruminants. Thus, a greater knowledge of the mechanisms underlying puberty process would lead to optimisation of commonly applied strategies for selection of replacement animals. In addition, understanding reproductive responses of animals to exteroceptive factors, such as photoperiod, nutrition and socio-sexual signals, will enable development and improvement of those management tools that that will fulfil the requirements of a 'clean, green and ethical' production. Copyright © 2012 Elsevier B.V. All rights reserved.
Paul, M; Kurtz, S
1994-03-01
Material Safety Data Sheets (MSDSs) are essential sources of information regarding health risks from exposure to toxic chemicals. We analyzed the reproductive health hazard descriptions on nearly 700 MSDSs for lead- or ethylene glycol ether-containing products submitted by central Massachusetts firms to the Department of Environmental Protection under provisions of the Massachusetts Right-to-Know Law. Over 60% of the MSDSs made no mention whatsoever of effects on the reproductive system. Those that did were much more likely to address developmental risks than male reproductive effects. The MSDSs from firms employing 100 or more workers mentioned reproductive system effects more frequently than those from smaller companies. While the informativeness of the health hazard descriptions increased over time, 53% of the MSDSs prepared after promulgation of the OSHA Hazard Communication Standard still contained no information on reproductive risks.
The psychology of antecedents to adult reproductive disorders in adolescent girls.
Covington, Sharon N; Martinez, Pedro E; Popat, Vaishali; Nandagopal, Radha; Ryan, Mary; Nelson, Lawrence M
2008-01-01
The normal developmental tasks and roles of adolescence are altered by a diagnosis of a reproductive disorder. The crisis of impaired fertility affects both parent and child, stressing the family system. For the adolescent girl, a reproductive disorder has an impact on her developing sense of self, body-image, and sexuality, which, in turn, can affect her self-esteem and relationships with others. Because of the sexual nature of a reproductive disorder, feelings of embarrassment or protectiveness are often engendered that can make it difficult for families to discuss. Nonetheless, families do best with openness and honesty regarding the condition and should be discouraged from keeping the diagnosis a secret. Adolescence encompasses a broad spectrum of emotional maturity, which needs to be considered by parents and clinicians when communicating information. Understanding that the family is an emotional unit, a family systems approach to deal with health issues is most appropriate. In this context, parents need to first deal with their own feelings about the diagnosis, before they can help their child. Secondly, parents must be provided with tools to build an ongoing conversation with their child that will avoid stigmatizing her condition and handicapping her growth into healthy adulthood. The goal for parent and clinician is to help the adolescent girl formulate positive self-esteem and body image, despite impaired fertility.
Mammalian target of rapamycin (mTOR): a central regulator of male fertility?
Jesus, Tito T.; Oliveira, Pedro F.; Sousa, M ario; Cheng, C. Yan; Alves, Marco G.
2017-01-01
Mammalian target of rapamycin (mTOR) is a central regulator of cellular metabolic phenotype and is involved in virtually all aspects of cellular function. It integrates not only nutrient and energy-sensing pathways but also actin cytoskeleton organization, in response to environmental cues including growth factors and cellular energy levels. These events are pivotal for spermato-genesis and determine the reproductive potential of males. Yet, the molecular mechanisms by which mTOR signaling acts in male reproductive system remain a matter of debate. Here, we review the current knowledge on physiological and molecular events mediated by mTOR in testis and testicular cells. In recent years, mTOR inhibition has been explored as a prime strategy to develop novel therapeutic approaches to treat cancer, cardiovascular disease, autoimmunity, and metabolic disorders. However, the physiological consequences of mTOR dysregulation and inhibition to male reproductive potential are still not fully understood. Compelling evidence suggests that mTOR is an arising regulator of male fertility and better understanding of this atypical protein kinase coordinated action in testis will provide insightful information concerning its biological significance in other tissues/organs. We also discuss why a new generation of mTOR inhibitors aiming to be used in clinical practice may also need to include an integrative view on the effects in male reproductive system. PMID:28124577
Yang, Qiangzhen; Li, Peifei; Wen, Yi; Li, Sisi; Chen, Jun; Liu, Xurui; Wang, Lirui; Li, Xinhong
2018-07-01
The toxic effects of cadmium (Cd) in the reproductive system have been confirmed, and lysine acetylation and succinylation play important roles in spermatogenesis. However, little attention determined whether Cd could affect lysine acylation and how it might have an impact on the reproductive system. Therefore, with the goal of contributing to this subject, we have examined the effects of Cd on lysine acetylation and succinylation of proteins in the germ cells of male mice testes during different developmental stages. We adopted intraperitoneal injection of cadmium chloride (1.2 mg/kg body weight) in mice once every 5 days from postnatal day 5-60. The results showed that Cd could restrict GAPDH activity, ATP and cAMP levels of germ cells to inhibit lysine acetylation and succinylation in the testes, inducing reproductive injuries. Cd also restricts acetylation of histone H4K5 and H4K12, which could result in failure of spermiogenesis. Remarkably, polarized acetylation occurs in meiosis, and high-level acetylation occurs earlier than high-level succinylation during spermatogenesis. Moreover, Cd has a limited effect on body weight but reduces the weight of the testis and litter size. Our research may provide a new way to reveal the mechanisms of Cd reproductive toxicity related to lysine acetylation and succinylation. Copyright © 2018. Published by Elsevier B.V.
Aging changes in the male reproductive system
... 004017.htm Aging changes in the male reproductive system To use the sharing features on this page, ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...
Nwaorgu, Obioma C; Onyeneho, Nkechi G; Okolo, May; Obadike, Ebele; Enibe, Gloria
2008-08-01
This was designed to provide background information for the implementation of family life and HIV/AIDS education in post primary schools in the Enugu State. A cross sectional survey of the reproductive health knowledge and practices of 412 junior secondary school pupils from 12 schools in Enugu State, Nigeria was undertaken using a uniform set of structured self-administered questionnaire. The results revealed that while the pupils demonstrated fair knowledge of human biology, they lacked knowledge of self-protective mechanisms as it related to sexual health. About (50%) of the participants reported that they have had sex, at the age of less than 11 years when they must have been in the primary school and most (89.3%) at age 11-14 years. Half (50.9%) of the respondents hold the belief that a girl would not get pregnant in her first sexual encounter. Statistically more of those who have ever had sex were betrayed this ignorance (p = 0.004). The boys were less certain about what constitutes the wrong ideas about reproductive health systems than the girls (p = 0.042). In the same vein, there was a difference (p < 0.0001) in the proportion of the rural residents, vis-a-vis their urban counterparts that could correctly identify the wrong ideas about human reproduction. This situation urgently calls for concerted efforts at addressing the poor reproductive health knowledge of these sexually active young people, for the millennium development goals (MDGs) target to be realized in Nigeria.
2012-01-01
Backgrounds Previous studies suggested that endocrine disruptors (ED) are toxic on preimplantation embryos and inhibit development of embryos in vitro culture. However, information about the toxicity of endocrine disruptors on preimplantation development of embryo in human reproductive environment is lacking. Methods Bisphenol A (BPA) and Aroclor 1254 (polychlorinated biphenyls) were used as endocrine disruptors in this study. Mouse 2-cell embryos were cultured in medium alone or vehicle or co-cultured with human endometrial epithelial layers in increasing ED concentrations. Results At 72 hours the percentage of normal blastocyst were decreased by ED in a dose-dependent manner while the co-culture system significantly enhanced the rate and reduced the toxicity of endocrine disruptors on the embryonic development in vitro. Conclusions In conclusion, although EDs have the toxic effect on embryo development, the co-culture with human endometrial cell reduced the preimplantation embryo from it thereby making human reproductive environment protective to preimplantation embryo from the toxicity of endocrine disruptors. PMID:22546201
Chromosomes, conflict, and epigenetics: chromosomal speciation revisited.
Brown, Judith D; O'Neill, Rachel J
2010-01-01
Since Darwin first noted that the process of speciation was indeed the "mystery of mysteries," scientists have tried to develop testable models for the development of reproductive incompatibilities-the first step in the formation of a new species. Early theorists proposed that chromosome rearrangements were implicated in the process of reproductive isolation; however, the chromosomal speciation model has recently been questioned. In addition, recent data from hybrid model systems indicates that simple epistatic interactions, the Dobzhansky-Muller incompatibilities, are more complex. In fact, incompatibilities are quite broad, including interactions among heterochromatin, small RNAs, and distinct, epigenetically defined genomic regions such as the centromere. In this review, we will examine both classical and current models of chromosomal speciation and describe the "evolving" theory of genetic conflict, epigenetics, and chromosomal speciation.
Nguyen, Philip V; Kafka, Jessica K; Ferreira, Victor H; Roth, Kristy; Kaushic, Charu
2014-01-01
The male and female reproductive tracts are complex microenvironments that have diverse functional demands. The immune system in the reproductive tract has the demanding task of providing a protective environment for a fetal allograft while simultaneously conferring protection against potential pathogens. As such, it has evolved a unique set of adaptations, primarily under the influence of sex hormones, which make it distinct from other mucosal sites. Here, we discuss the various components of the immune system that are present in both the male and female reproductive tracts, including innate soluble factors and cells and humoral and cell-mediated adaptive immunity under homeostatic conditions. We review the evidence showing unique phenotypic and functional characteristics of immune cells and responses in the male and female reproductive tracts that exhibit compartmentalization from systemic immunity and discuss how these features are influenced by sex hormones. We also examine the interactions among the reproductive tract, sex hormones and immune responses following HIV-1 infection. An improved understanding of the unique characteristics of the male and female reproductive tracts will provide insights into improving clinical treatments of the immunological causes of infertility and the design of prophylactic interventions for the prevention of sexually transmitted infections. PMID:24976268
Stress and its influence on reproduction in pigs: a review
Einarsson, Stig; Brandt, Ylva; Lundeheim, Nils; Madej, Andrzej
2008-01-01
The manifestations of stress, defined as a biological response to an event that the individual perceives as a threat to its homeostasis, are commonly linked to enhanced activity of the hypothalamo-pituitary-adrenal (HPA) axis and the activation of the sympathetic adreno-medullary (SA) system. Activation of the HPA system results in the secretion of peptides from the hypothalamus, principally corticotropin releasing hormone (CRH), which stimulates the release of adrenocorticotropic hormone (ACTH) and beta-endorphin. ACTH induces the secretion of corticosteroids from the adrenal cortex, which can be seen in pigs exposed to acute physical and/or psychological stressors. The present paper is a review of studies on the influence of stressors on reproduction in pigs. The effects of stress on reproduction depend on the critical timing of stress, the genetic predisposition to stress, and the type of stress. The effect of stress on reproduction is also influenced by the duration of the responses induced by various stressors. Prolonged or chronic stress usually results in inhibition of reproduction, while the effects of transient or acute stress in certain cases is stimulatory (e.g. anoestrus), but in most cases is of impairment for reproduction. Most sensitive of the reproductive process are ovulation, expression of sexual behaviour and implantation of the embryo, since they are directly controlled by the neuroendocrine system. PMID:19077201
[Human rights, maternal mortality and reproductive health].
Cook, R J
1993-06-01
This work examines reproductive health within the framework of human rights assured by various international conventions, and analyzes the high maternal mortality rates of developing countries as a violation of several guaranteed rights. The 1st of 3 main sections of the report discusses the failure of governments to make protection of women's reproductive health a priority. Historically, women's principal role has been to bear children, and no recognition was given to the cost in health of accomplishing this duty. Women's reproductive health has created controversies in many traditional juridical systems because of its relation to human sexuality and morals. WHO has estimated that some 500,000 maternal deaths occur each year, with 25-50% resulting from unsafe abortions. The causes of maternal mortality often have their roots in the poor nutrition or inadequate health care provided to the woman long before the 1st pregnancy. Early and frequent pregnancies and heavy physical labor are among the many factors that contribute to maternal death. Laws to protect women's health may be lacking or may not be applied. For example, many countries have no legal minimum age for marriage. To combat the traditional negligence, a new viewpoint is emerging which views women's reproductive health as a condition in which childbearing occurs in a state of physical, mental, and social wellbeing. It implies that women have the capacity to reproduce, regulate their fertility, and enjoy sexual relations. Laws that deny access to reproductive health services or place obstacles or conditions in the way are coming under question as violations of basic human rights of women protected by international conventions. The main such convention discussed in this article is the Convention on the Elimination of All Forms of Discrimination Against Women, although several other conventions are relevant to protecting women's reproductive health. If international law on human rights is to become truly universal, it is necessary to require that nations take preventive and curative measures to protect women's reproductive health and provide women with the capacity for reproductive self-determination. International human rights treaties require that national and international laws guarantee the rights of women to be free from discrimination; enjoy the rights to marriage and formation of a family; rights to private and family life; rights to information and education; and access to medical attention and to the benefits of scientific progress. The 2nd major section of this work discusses interpretations of these treaties using empirical evidence and feminist juridical principles. The 3rd section discusses international protection of women's reproductive rights, including the reporting system and specific categories of clearly differentiable rights.
Jing, Xiaoping; Peng, Quanhui; Hu, Rui; Wang, Hongze; Yu, Xiaoqiang; Degen, Allan; Zou, Huawei; Bao, Shanke; Zhao, Suonan; Wang, Zhisheng
2017-09-01
We examined the development of the reproductive system in prepubertal Tibetan sheep ewes when fed only oat hay (CON) or supplemented with either lick blocks (BS) or concentrate feed (CS) during the cold season. The average daily gain of the CS ewes was greater than that of the BS ewes (P < 0.05), which was greater than that of the CON ewes. The same pattern was observed in the number of ovarian follicles (P < 0.001), that is, CS > BS > CON. Serum concentrations of gonadotropin-releasing hormone, follicle-stimulating hormone, luteotrophic hormone, estradiol and progesterone in the CS and BS groups were higher than in the CON group (P < 0.05). The messenger RNA (mRNA) expression of KiSS-1, GPR54 (G protein-coupled receptor 54), ERα (estradiol receptor α) in the hypothalamic anteroventral periventricular area of the CS group were higher than in both the BS and CON groups (P < 0.05), while the BS group was higher than in the CON group (P < 0.05). Similar differences among groups were observed for gonadotropin-releasing hormone receptor mRNA expression in the pituitary, follicle-stimulating hormone receptor and luteinizing hormone receptor mRNA expression in the ovary. These results indicated that the KiSS1/GPR54 system was more active with nutrition or trace mineral supplementation during the cold season. The system stimulated the hypothalamic-pituitary-gonadal axis and enhanced folliclar development in prepubertal Tibetan sheep ewes. We concluded that energy, protein and trace minerals supplements could improve the reproductive performance of Tibetan sheep on the Qinghai-Tibetan plateau. © 2017 Japanese Society of Animal Science.
Midwifery 2030: a woman's pathway to health. What does this mean?
ten Hoope-Bender, Petra; Lopes, Sofia Tavares Castro; Nove, Andrea; Michel-Schuldt, Michaela; Moyo, Nester T; Bokosi, Martha; Codjia, Laurence; Sharma, Sheetal; Homer, Caroline
2016-01-01
The 2014 State of the World's Midwifery report included a new framework for the provision of woman-centred sexual, reproductive, maternal, newborn and adolescent health care, known as the Midwifery2030 Pathway. The Pathway was designed to apply in all settings (high-, middle- and low-income countries, and in any type of health system). In this paper, we describe the process of developing the Midwifery2030 Pathway and explain the meaning of its different components, with a view to assisting countries with its implementation. The Pathway was developed by a process of consultation with an international group of midwifery experts. It considers four stages of a woman's reproductive life: (1) pre-pregnancy, (2) pregnancy, (3) labour and birth, and (4) postnatal, and describes the care that women and adolescents need at each stage. Underpinning these four stages are ten foundations, which describe the systems, services, workforce and information that need to be in place in order to turn the Pathway from a vision into a reality. These foundations include: the policy and working environment in which the midwifery workforce operates, the effective coverage of sexual, reproductive, maternal, newborn and adolescent services (i.e. going beyond availability and ensuring accessibility, acceptability and high quality), financing mechanisms, collaboration between different sectors and different levels of the health system, a focus on primary care nested within a functional referral system when needed, pre- and in-service education for the workforce, effective regulation of midwifery and strengthened leadership from professional associations. Strengthening of all of these foundations will enable countries to turn the Pathway from a vision into reality. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Heme oxygenase/carbon monoxide in the female reproductive system: an overlooked signalling pathway
Němeček, David; Dvořáková, Markéta; Sedmíková, Markéta
2017-01-01
For a long time, carbon monoxide (CO) was known for its toxic effect on organisms. But there are still many things left to discover on that molecule. CO is formed directly in the body by the enzymatic activity of heme oxygenase (HO). CO plays an important role in many physiological processes, such as cell protections (against various stress factors), and the regulation of metabolic processes. Recent research proves that CO also operates in the female reproductive system. At the centre of interest is the importance of CO for gestation. During the gestation period, CO is an important element affecting the proper function of the feto-placental unit and generally affects fetal survivability rates. Gestation is one of the most important processes of successful reproduction, although there are more relevant processes that need to be researched. While already proven that CO influences steroidogenesis and the corpus luteum survivability rate, our knowledge concerning the function and importance of CO in the reproductive system is still relatively limited. As an example, our knowledge of CO function in an oocyte, the most important cell for reproduction, is almost non-existent. The aim of this review is to summarize our current knowledge concerning the function of CO in the female reproductive system. PMID:28123837
[Prevention and protection of workers' reproductive health].
Sivochalova, O V; Fesenko, M A; Golovaneva, G V; Morozova, T V; Fedorova, E V; Irmiakova, A R; Gromova, E Iu; Stepanian, I V; Vuĭtsik, P A
2013-01-01
The article mentiones issues of preserving and strengthening the reproductive health of women workers, dealed by researchers of the laboratory, established in 1974. It describes the developed concept of the reproductive health problems and scientific research areas, developed documents, including legislative fields, formulates main prospects of the laboratory to meet the requirements of the present moment. Noted the role of the Problem Commission "Scientific basis for the reproductive health of workers", in the work of the Scientific Council on medical and environmental issues of workers' health.
Vereshchako, G G; Chueshova, N V; Gorokh, G A; Naumov, A D
2014-01-01
The consequences of prolonged exposure to electromagnetic radiation from cellular phone (897 MHz, daily 8 h/day) in male rats of the 1st generation obtained from irradiated parents and subjected to prolonged exposure to electromagnetic radiation of the range of mobile communications during ontogeny and postnatal development were studied. It has been found that irradiation causes a decrease in the number of births of animals, changing the sex ratio towards the increase in the number of males. It had a significant impact on the reproductive system of males, accelerating their sexual development, revealed at the age of two months. Radiation from cell phones led to significant disproportions in the cell number at different stages of spermatogenesis. It increased the number of mature spermatozoa which decreased viability.
Stem cells, in vitro gametogenesis and male fertility.
Nagamatsu, Go; Hayashi, Katsuhiko
2017-12-01
Reconstitution in culture of biological processes, such as differentiation and organization, is a key challenge in regenerative medicine, and one in which stem cell technology plays a central role. Pluripotent stem cells and spermatogonial stem cells are useful materials for reconstitution of germ cell development in vitro , as they are capable of differentiating into gametes. Reconstitution of germ cell development, termed in vitro gametogenesis, will provide an experimental platform for a better understanding of germ cell development, as well as an alternative source of gametes for reproduction, with the potential to cure infertility. Since germ cells are the cells for 'the next generation', both the culture system and its products must be carefully evaluated. In this issue, we summarize the progress in in vitro gametogenesis, most of which has been made using mouse models, as well as the future challenges in this field. © 2017 Society for Reproduction and Fertility.
Epigenetic impacts of endocrine disruptors in the brain☆
Walker, Deena M.; Gore, Andrea C.
2017-01-01
The acquisition of reproductive competence is organized and activated by steroid hormones acting upon the hypothalamus during critical windows of development. This review describes the potential role of epigenetic processes, particularly DNA methylation, in the regulation of sexual differentiation of the hypothalamus by hormones. We examine disruption of these processes by endocrine-disrupting chemicals (EDCs) in an age-, sex-, and region-specific manner, focusing on how perinatal EDCs act through epigenetic mechanisms to reprogram DNA methylation and sex steroid hormone receptor expression throughout life. These receptors are necessary for brain sexual differentiation and their altered expression may underlie disrupted reproductive physiology and behavior. Finally, we review the literature on histone modifications and non-coding RNA involvement in brain sexual differentiation and their perturbation by EDCs. By putting these data into a sex and developmental context we conclude that perinatal EDC exposure alters the developmental trajectory of reproductive neuroendocrine systems in a sex-specific manner. PMID:27663243
Amastae, Jon; Potter, Joseph E.; Hopkins, Kristine; Grossman, Daniel
2013-01-01
Inherent in many reproductive health and family planning programmes is the problematic assumption that the body, its processes, and modifications to it are universally experienced in the same way. This paper addresses contraceptive knowledge and beliefs among Mexican-origin women, based upon data gathered by the qualitative component of the Border Contraceptive Access Study. Open-ended interviews explored the perceived mechanism of action of the pill, side effects, non-contraceptive benefits, and general knowledge of contraception. Findings revealed complex connections between traditional and scientific information. Use of medical terms (“hormone”) illustrated attempts to integrate new information with existing knowledge and belief systems. Conclusions address concerns that existing information and services may not be sufficient if population-specific knowledge and beliefs are not assessed and addressed. Findings can contribute to the development of effective education, screening, and reproductive health services. PMID:23464742
Development of an in vitro test system for assessment of male, reproductive toxicity.
Habas, Khaled; Anderson, Diana; Brinkworth, Martin
2014-02-10
There is a need for improved reproductive toxicology assays that do not require large numbers of animals but are sensitive and informative. Therefore, Staput velocity-sedimentation separation followed by culture of specific mouse testicular cells was used as such a system. The specificity of separation was assessed using immunocytochemistry to identify spermatids, spermatocytes and spermatogonia. The efficacy of the system to detect toxicity was then evaluated by analysing the effects of hydrogen peroxide (H2O2) by the terminal uridine-deoxynucleotide end-labelling (TUNEL) assay to show the rate of apoptosis induced among the different types of germ cells. We found that 2 h of treatment at both 1 and 10 μM induced increases of over ∼10-fold in the percentage of apoptotic cells (p≤0.001), confirming that testicular germ cells are prone to apoptosis at very low concentrations of H2O2. It was also demonstrated for the first time for this compound that spermatogonia are significantly more susceptible than spermatocytes, which are more affected than spermatids. This reflects the proportion of actively dividing cells in these cell types, suggesting a mechanism for the differential sensitivity. The approach should thus form the basis of a useful test system for reproductive and genetic toxicology in the future. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Sexual and reproductive health and rights of older men and women: addressing a policy blind spot.
Aboderin, Isabella
2014-11-01
Global debate on required policy responses to issues of older persons has intensified over the past 15 years, fuelled by a growing awareness of the rapid ageing of populations. Health has been a central focus, but scrutiny of global policies, human rights instruments and reports reveals that just as older people are excluded from sexual and reproductive health and rights agendas, so are issues of sexual and reproductive health and rights wholly marginal to current agendas focused on older people. A critical question is whether the policy lacuna reflects a dearth of research evidence or a faulty translation of existing knowledge. A reading of the current research landscape and literature, summarised in this paper, strongly suggests it is the former. To be sure, sexuality in old age is a burgeoning field of scientific inquiry. What the existing knowledge and discourse fail to provide is an engagement with, and elucidation of, the broader sexual and reproductive health and rights agenda as it relates to older persons. A concerted research effort is needed to provide a basis for developing policy guidance and for pinpointing essential indicators and establishing necessary data systems to enable a routine tracking of progress. Copyright © 2014 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
Pathogenesis and Transmission of Feral Swine Pseudorabies Virus Isolates in Domestic Pigs
USDA-ARS?s Scientific Manuscript database
Pseudorabies is one of the oldest described swine diseases recognized as reproductive failure, and respiratory and central nervous system disease. It is caused by pseudorabies virus (PRV). The development of vaccines and serologic tests that allow the differentiation of vaccinated pigs from naturall...
Regenerating Longleaf Pine Naturally
Thomas C. Croker; William D. Boyer
1975-01-01
Research has developed guides for consistent natural regeneration of longleaf pine by a shelterwood system. Key measures include hardwood control by fire and other means, timely preparatory and seed cuts, seed crop monitoring, seedbed preparation, protection of established seedlings, prompt removal of parent trees when reproduction is adequate, and control of...
Lebigre, Christophe; Arcese, Peter; Reid, Jane M
2013-07-01
Age-specific variances and covariances in reproductive success shape the total variance in lifetime reproductive success (LRS), age-specific opportunities for selection, and population demographic variance and effective size. Age-specific (co)variances in reproductive success achieved through different reproductive routes must therefore be quantified to predict population, phenotypic and evolutionary dynamics in age-structured populations. While numerous studies have quantified age-specific variation in mean reproductive success, age-specific variances and covariances in reproductive success, and the contributions of different reproductive routes to these (co)variances, have not been comprehensively quantified in natural populations. We applied 'additive' and 'independent' methods of variance decomposition to complete data describing apparent (social) and realised (genetic) age-specific reproductive success across 11 cohorts of socially monogamous but genetically polygynandrous song sparrows (Melospiza melodia). We thereby quantified age-specific (co)variances in male within-pair and extra-pair reproductive success (WPRS and EPRS) and the contributions of these (co)variances to the total variances in age-specific reproductive success and LRS. 'Additive' decomposition showed that within-age and among-age (co)variances in WPRS across males aged 2-4 years contributed most to the total variance in LRS. Age-specific (co)variances in EPRS contributed relatively little. However, extra-pair reproduction altered age-specific variances in reproductive success relative to the social mating system, and hence altered the relative contributions of age-specific reproductive success to the total variance in LRS. 'Independent' decomposition showed that the (co)variances in age-specific WPRS, EPRS and total reproductive success, and the resulting opportunities for selection, varied substantially across males that survived to each age. Furthermore, extra-pair reproduction increased the variance in age-specific reproductive success relative to the social mating system to a degree that increased across successive age classes. This comprehensive decomposition of the total variances in age-specific reproductive success and LRS into age-specific (co)variances attributable to two reproductive routes showed that within-age and among-age covariances contributed substantially to the total variance and that extra-pair reproduction can alter the (co)variance structure of age-specific reproductive success. Such covariances and impacts should consequently be integrated into theoretical assessments of demographic and evolutionary processes in age-structured populations. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.
Darwinism without populations: a more inclusive understanding of the "Survival of the Fittest".
Bouchard, Frédéric
2011-03-01
Following Wallace's suggestion, Darwin framed his theory using Spencer's expression "survival of the fittest". Since then, fitness occupies a significant place in the conventional understanding of Darwinism, even though the explicit meaning of the term 'fitness' is rarely stated. In this paper I examine some of the different roles that fitness has played in the development of the theory. Whereas the meaning of fitness was originally understood in ecological terms, it took a statistical turn in terms of reproductive success throughout the 20th Century. This has lead to the ever-increasing importance of sexually reproducing organisms and the populations they compose in evolutionary explanations. I will argue that, moving forward, evolutionary theory should look back at its ecological roots in order to be more inclusive in the type of systems it examines. Many biological systems (e.g. clonal species, colonial species, multi-species communities) can only be satisfactorily accounted for by offering a non-reproductive account of fitness. This argument will be made by examining biological systems with very small or transient population structures. I argue this has significant consequences for how we define Darwinism, increasing the significance of survival (or persistence) over that of reproduction. Copyright © 2010 Elsevier Ltd. All rights reserved.
Evidence of natural reproduction by Muskellunge in middle Tennessee rivers
Warren, Lila H.; Bettoli, Phillip William
2014-01-01
Native Esox masquinongy (Muskellunge) in the Cumberland River drainage, TN, were nearly extirpated in the 1970s due to decades of over-fishing and habitat degradation from coal mining, logging, and other land-use practices. In an effort to preserve the species in that drainage, a stocking program began in 1976 in the upper Caney Fork River system in middle Tennessee where Muskellunge were not native. A trophy Muskellunge fishery eventually developed, but it was unknown whether Muskellunge were reproducing in the upper Caney Fork River system or whether the fishery was wholly dependent on the stocking program. To establish evidence of natural reproduction, we used seines, backpack electrofishing, and boat electrofishing gear in 2012 to find age-0 Muskellunge in the upper Caney Fork River system. Natural reproduction of Muskellunge was documented in the mainstem Caney Fork River above Great Falls Dam and in 3 of its 4 major tributaries. Seventeen age-0 Muskellunge were collected and one other was observed, but not handled. Age-0 Muskellunge grew rapidly (1.80–2.34 mm/day), and the largest fish collected during the study reached a total length of 399 mm by 9 October 2012. A cessation of stocking for several years coupled with routine monitoring could reveal whether natural recruitment is sufficient to sustain the fishery.
Sociality, mating system and reproductive skew in marmots: evidence and hypotheses.
Allainé
2000-10-05
Marmot species exhibit a great diversity of social structure, mating systems and reproductive skew. In particular, among the social species (i.e. all except Marmota monax), the yellow-bellied marmot appears quite different from the others. The yellow-bellied marmot is primarily polygynous with an intermediate level of sociality and low reproductive skew among females. In contrast, all other social marmot species are mainly monogamous, highly social and with marked reproductive skew among females. To understand the evolution of this difference in reproductive skew, I examined four possible explanations identified from reproductive skew theory. From the literature, I then reviewed evidence to investigate if marmot species differ in: (1) the ability of dominants to control the reproduction of subordinates; (2) the degree of relatedness between group members; (3) the benefit for subordinates of remaining in the social group; and (4) the benefit for dominants of retaining subordinates. I found that the optimal skew hypothesis may apply for both sets of species. I suggest that yellow-bellied marmot females may benefit from retaining subordinate females and in return have to concede them reproduction. On the contrary, monogamous marmot species may gain by suppressing the reproduction of subordinate females to maximise the efficiency of social thermoregulation, even at the risk of departure of subordinate females from the family group. Finally, I discuss scenarios for the simultaneous evolution of sociality, monogamy and reproductive skew in marmots.
Munro, Malcolm G; Critchley, Hilary O D; Fraser, Ian S
2012-10-01
In November 2010, the International Federation of Gynecology and Obstetrics formally accepted a new classification system for causes of abnormal uterine bleeding in the reproductive years. The system, based on the acronym PALM-COEIN (polyps, adenomyosis, leiomyoma, malignancy and hyperplasia-coagulopathy, ovulatory disorders, endometrial causes, iatrogenic, not classified) was developed in response to concerns about the design and interpretation of basic science and clinical investigation that relates to the problem of abnormal uterine bleeding. A system of nomenclature for the description of normal uterine bleeding and the various symptoms that comprise abnormal bleeding has also been included. This article describes the rationale, the structured methods that involved stakeholders worldwide, and the suggested use of the International Federation of Gynecology and Obstetrics system for research, education, and clinical care. Investigators in the field are encouraged to use the system in the design of their abnormal uterine bleeding-related research because it is an approach that should improve our understanding and management of this often perplexing clinical condition. Copyright © 2012. Published by Mosby, Inc.
Cooperation, conflict, and the evolution of queen pheromones.
Kocher, Sarah D; Grozinger, Christina M
2011-11-01
While chemical communication regulates individual behavior in a wide variety of species, these communication systems are most elaborated in insect societies. In these complex systems, pheromones produced by the reproductive individuals (queens) are critical in establishing and maintaining dominant reproductive status over hundreds to thousands of workers. The proximate and ultimate mechanisms by which these intricate pheromone communication systems evolved are largely unknown, though there has been much debate over whether queen pheromones function as a control mechanism or as an honest signal facilitating cooperation. Here, we summarize results from recent studies in honey bees, bumble bees, wasps, ants and termites. We further discuss evolutionary mechanisms by which queen pheromone communication systems may have evolved. Overall, these studies suggest that queen-worker pheromone communication is a multi-component, labile dialog between the castes, rather than a simple, fixed signal-response system. We also discuss future approaches that can shed light on the proximate and ultimate mechanisms that underlie these complex systems by focusing on the development of increasingly sophisticated genomic tools and their potential applications to examine the molecular mechanisms that regulate pheromone production and perception.
Elias, Carol F
2014-01-01
The remarkable development and refinement of the Cre-loxP system coupled with the nonstop production of new mouse models and virus vectors have impelled the growth of various fields of investigation. In this article, I will discuss the data collected using these genetic tools in our area of interest, giving specific emphasis to the identification of the neuronal populations that relay leptin action in reproductive physiology. A series of mouse models that allow manipulation of the leptin receptor gene have been generated. Of those, I will discuss the use of two models of leptin receptor gene reexpression (LepR(neo/neo) and LepR(loxTB/loxTB)) and one model of leptin signaling blockade (LepR(flox/flox)). I will also highlight the differences of using stereotaxic delivery of virus vectors expressing DNA-recombinases (Flp and Cre) and mouse models expressing Cre-recombinase. Our findings indicate that leptin action in the ventral premammillary nucleus is sufficient, but not required, for leptin action in reproduction and that leptin action in Kiss1 neurons arises after pubertal maturation; therefore, direct leptin signaling in Kiss1 neurons is neither required nor sufficient for the permissive action of leptin in pubertal development. It also became evident that the full action of leptin in the reproductive neuroendocrine axis requires the engagement of an integrated circuitry, yet to be fully unveiled.
Synchronisation of ovulation for management of reproduction in dairy cows.
Bisinotto, R S; Ribeiro, E S; Santos, J E P
2014-05-01
Important developments have occurred in the last two decades, since the advent of the Ovsynch protocol, on the understanding and use of synchronisation programmes for management of reproduction in dairy herds. This better understanding of oestrus cycle control associated with suboptimal reproductive performance in dairy herds has led dairy producers to quickly adopt timed artificial insemination (AI) protocols. Recent surveys have documented that fixed-time AI has become an important component of management of reproduction in high-producing herds. Furthermore, timed AI protocols have also demonstrated benefits in pasture-based milk production systems because of the ability to increase insemination rate. In general, successful use of the Ovsynch protocol requires some fundamental physiological principles to be respected, including: induction of ovulation to synchronise follicle growth in the first 2 days of the programme such that a young antral follicle is recruited; maintenance of high concentrations of progesterone during the development of the ovulatory follicle, but also effectively lyse the corpus luteum to result in very low concentration of progesterone at AI; and having a healthy pre-ovulatory follicle of moderate diameter that is highly oestrogenic and responsive to gonadotropins to synchronously ovulate 12 to 18 h after insemination. Current methods oestrous and ovulation synchronisation are still not optimal and future improvements will likely require new technologies for hormone formulation and delivery such that additional interventions are minimised to maintain acceptance by producers.
Zhang, Zhengqing; Wang, Huapeng; Hao, Chunfeng; Zhang, Wei; Yang, Miaomiao; Chang, Yong; Li, Menglou
2016-10-21
Dastarcus helophoroides , which has a relatively longer lifespan compared to other insects, is one of the most effective natural enemies of many large-body long-horned beetles. Methuselah (Mth) is associated with the lifespan, stress resistance, and reproduction in Drosophila melanogaster , but Mth is not present in non-drosophiline insects. A number of methuselah-like genes ( mth-likes , mthls ) have been identified in non-drosophiline insects, but it is still unknown whether they are present in Dastarcus helophoroides . We identified three novel mth-like genes in D. helophoroides : mth-like1 , mth-like2 , and mth-like5 , and carried out bioinformatic analysis based on the full-length nucleic acid sequences and deduced amino acid sequences. Real-time quantitative polymerase chain reaction (RT-qPCR) showed variations in expression patterns of mth-like genes in different tissues (highly expressed in reproductive systems) and at different developmental stages, indicating that mth-likes were likely be involved in reproduction and development. The altered mRNA expression in aging adults and under oxidation, high temperature, and starvation stress, indicated that mth-like genes were likely to be involved in aging and the resistance of oxidation, high temperature, and starvation. These results characterize, for the first time, the basic properties of three mth-like genes from D. helophoroides that probably play important roles in development, aging, reproduction, and stress resistance.
Munro, Malcolm G
2017-04-01
The FIGO systems defining the nomenclature and symptoms of abnormal uterine bleeding (AUB) in the reproductive years (System 1) and the PALM-COEIN classification of causes of AUB (System 2) are designed to facilitate research, education, and the provision of optimum clinical care for affected women. Development of these systems has been the result of a collaborative effort of experts in bench and translational and clinical research from six continents aided by a spectrum of representatives from relevant medical societies, journals, and regulatory bodies. Integral to this development has been a decision to cease the use of poorly defined and inconsistently used terms such as menorrhagia, metrorrhagia, and dysfunctional uterine bleeding, to name a few, and replace them with a set of terms and definitions that are relatively easily understood and translated into the spectrum of languages used by medical providers and patients globally. The utilization of these systems requires a disciplined approach to obtaining a menstrual history, relatively simple laboratory investigations, and the appropriate use of imaging techniques accessible to most clinicians worldwide. This section describes the two systems, their crucial role in guiding investigation, and an approach to implementation, all designed to facilitate the creation of a menu of therapeutic options, considering the identified factors contributing to the problem of nongestational AUB. Copyright © 2016. Published by Elsevier Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eskenazi, B.; Kimmel, G.
This summary report focuses on current studies on reproductive effects reported at the workshop on Perinatal Exposure to Dioxin-like Compounds and supporting data noted in the discussion. Recent laboratory studies have suggested that altered development (e.g., low birth weight, spontaneous abortion, congenital malformation) and reproductive health (e.g., fertility, sex organ development, reproductive behavior) may be among the most sensitive end points when examining the effects of dioxin-like compounds. Thus, future research should target the reproductive health of both males and females exposed postnatally and prenatally. Studies in humans are needed and are on-going. In animal models, postnatal exposure to dioxinmore » or dioxinlike compounds has been associated with abnormal spermatogenesis and abnormal testicular morphology and size in males and with reduced fertility and endometriosis in females. In utero exposure may also produce profound reproductive consequences in both males and females including delays in sexual maturation, abnormalities in development of sexual organs, and abnormal sexual behavior. The mechanism by which dioxin-like compounds cause reproductive effects is not well delineated. 13 refs.« less
Gender issues in reproductive health: a review.
Adinma, Echendu D; Adinma, Brian-D J I
2011-01-01
Gender, for its impact on virtually every contemporary life issue, can rightly be regarded as a foremost component of reproductive health. Reproductive health basically emphasises on people and their rights to sexuality, reproduction, and family planning, and the information to actualize these right, which has been inextricably linked to development at the International Conference on Population and Development (ICPD) held in Cairo, Egypt, in 1994. Women's sexual and reproductive rights became recognised as universal human right, violations of which occur in some reproductive health areas including gender concerns. Gender inequality and inequity encompass gender based violence as well as gender discrimination which cuts across the life cycle of the woman; attitudes, religious and cultural practices of various nations; and issues related to employment, economy, politics, and development. The redress of gender inequality is a collective responsibility of nations and supranational agencies. Nations should adopt a framework hinged on three pedestals--legal, institutional and policy, employing the three recommended approaches of equal treatment, positive action, and gender mainstreaming.
Spaceborne synthetic aperture radar signal processing using FPGAs
NASA Astrophysics Data System (ADS)
Sugimoto, Yohei; Ozawa, Satoru; Inaba, Noriyasu
2017-10-01
Synthetic Aperture Radar (SAR) imagery requires image reproduction through successive signal processing of received data before browsing images and extracting information. The received signal data records of the ALOS-2/PALSAR-2 are stored in the onboard mission data storage and transmitted to the ground. In order to compensate the storage usage and the capacity of transmission data through the mission date communication networks, the operation duty of the PALSAR-2 is limited. This balance strongly relies on the network availability. The observation operations of the present spaceborne SAR systems are rigorously planned by simulating the mission data balance, given conflicting user demands. This problem should be solved such that we do not have to compromise the operations and the potential of the next-generation spaceborne SAR systems. One of the solutions is to compress the SAR data through onboard image reproduction and information extraction from the reproduced images. This is also beneficial for fast delivery of information products and event-driven observations by constellation. The Emergence Studio (Sōhatsu kōbō in Japanese) with Japan Aerospace Exploration Agency is developing evaluation models of FPGA-based signal processing system for onboard SAR image reproduction. The model, namely, "Fast L1 Processor (FLIP)" developed in 2016 can reproduce a 10m-resolution single look complex image (Level 1.1) from ALOS/PALSAR raw signal data (Level 1.0). The processing speed of the FLIP at 200 MHz results in twice faster than CPU-based computing at 3.7 GHz. The image processed by the FLIP is no way inferior to the image processed with 32-bit computing in MATLAB.
Croizet, Jean-Claude; Goudeau, Sébastien; Marot, Medhi; Millet, Mathias
2017-12-01
This article examines how the educational system participates in the reproduction of social inequality. After exposing the basics of the Social Reproduction Theory developed in sociology by Bourdieu and Passeron in 1977, we examine the research in social psychology that documents the reality of 'symbolic violence' that is the symbolic power that operates in the classroom and undermines the performance of students from underprivileged backgrounds. Three lines of research are examined: self-esteem, self-threat and research on the non-neutrality of educational settings. Copyright © 2017 Elsevier Ltd. All rights reserved.
Remington, David L; Figueroa, Jennifer; Rane, Mitali
2015-09-17
Perenniality is best understood in quantitative terms, involving the relationship between production vs. turnover of meristems, biomass, or energy reserves. Previous quantitative trait locus (QTL) studies using divergent populations of the perennial rock cress Arabidopsis lyrata have shown that trade-offs in vegetative growth vs. reproduction are due to cascading effects of differences in early vegetative development, which contribute to local adaptation. However, details of the developmental differences and how they affect perenniality remained unclear. In this study, we investigated in detail the developmental differences in perenniality between populations. A. lyrata from Norway and North Carolina populations, representing contrasting environments and degrees of perenniality, were grown under controlled conditions, and data were collected on plant phenology and shoot-level development. We tested hypotheses that differences in perenniality involve strict allocation of lateral meristems to vegetative vs. reproductive fates, or alternatively quantitative effects of pre-reproductive vegetative development. The two populations showed large differences in the degree of vegetative development on individual shoots prior to reproductive transitions. The number of leaves produced on shoots prior to bolting, and not strict meristem allocation or variation in apical dominance, was able to explain variation in the number of inflorescences on individual plants. These results suggested that allocation of time to shoot vegetative vs. reproductive development could be a major factor in resource allocation differences between the populations. Based on these results and those of previous QTL studies, we propose a model in which the degree of shoot vegetative development shapes the developmental context for reproduction and subsequent vegetative growth in different environments. Climate-specific effects of shoot development patterns on reproductive output and survival may result in divergent evolutionary trajectories along a perenniality continuum, which may have broader relevance for plant life history evolution.
Incorporating reproductive endpoints into sediment toxicity tests has become an important consideration in ecological risk assessments. The capacity to assess reproduction was one of the primary objectives underlying the recent development of a life-cycle test with the midge, Ch...
Toxic plants: Effects on reproduction and fetal and embryonic development in livestock
USDA-ARS?s Scientific Manuscript database
Reproductive success is dependent on a large number of carefully orchestrated biological events that must occur in a specifically timed sequence. The interference with one of more of these sequences or events may result in total reproductive failure or a more subtle reduction in reproductive potent...
Endocrine Disruptors in Domestic Animal Reproduction: A Clinical Issue?
Magnusson, Ulf; Persson, Sara
2015-01-01
Contents The objective of this review was to discuss whether endocrine disruption is a clinical concern in domestic animal reproduction. To that end, we firstly summarize the phenomenon of endocrine disruption, giving examples of the agents of concern and their effects on the mammalian reproductive system. Then there is a brief overview of the literature on endocrine disruptors and domestic animal reproduction. Finally, the clinical implications of endocrine disruptors on the reproductive system of farm animals as well as in dogs and cats are discussed. It is concluded that the evidence for clinical cases of endocrine disruption by chemical pollutants is weak, whereas for phytooestrogens, it is well established. However, there is concern that particular dogs and cats may be exposed to man-made endocrine disruptors. PMID:26382024
Zhou, Shuzhi; Holmes, Melissa M; Forger, Nancy G; Goldman, Bruce D; Lovern, Matthew B; Caraty, Alain; Kalló, Imre; Faulkes, Christopher G; Coen, Clive W
2013-09-01
In naked mole-rat (NMR) colonies, breeding is monopolized by the queen and her consorts. Subordinates experience gonadal development if separated from the queen. To elucidate the neuroendocrine factors underlying reproductive suppression/development in NMRs, we quantified plasma gonadal steroids and GnRH-1- and kisspeptin-immunoreactive (ir) neurons in subordinate adults and in those allowed to develop into breeders, with or without subsequent gonadectomy. In males and females, respectively, plasma testosterone and progesterone are higher in breeders than in subordinates. No such distinction occurs for plasma estradiol; its presence after gonadectomy and its positive correlation with adrenal estradiol suggest an adrenal source. Numbers of GnRH-1-ir cell bodies do not differ between gonad-intact breeders and subordinates within or between the sexes. As in phylogenetically related guinea pigs, kisspeptin-ir processes pervade the internal and external zones of the median eminence. Their distribution is consistent with actions on GnRH-1 neurons at perikaryal and/or terminal levels. In previously investigated species, numbers of kisspeptin-ir cell bodies vary from substantial to negligible according to sex and/or reproductive state. NMRs are exceptional: irrespective of sex, reproductive state, or presence of gonads, substantial numbers of kisspeptin-ir cell bodies are detected in the rostral periventricular region of the third ventricle (RP3V) and in the anterior periventricular (PVa), arcuate, and dorsomedial hypothalamic nuclei. Nevertheless, the greater number in the RP3V/PVa of female breeders compared with female subordinates or male breeders suggests that emergence from a hypogonadotrophic state in females may involve kisspeptin-related mechanisms similar to those underlying puberty or seasonal breeding in other species. Copyright © 2013 Wiley Periodicals, Inc.
Williams, N I; Caston-Balderrama, A L; Helmreich, D L; Parfitt, D B; Nosbisch, C; Cameron, J L
2001-06-01
Cross-sectional studies of exercise-induced reproductive dysfunction have documented a high proportion of menstrual cycle disturbances in women involved in strenuous exercise training. However, longitudinal studies have been needed to examine individual susceptibility to exercise-induced reproductive dysfunction and to elucidate the progression of changes in reproductive function that occur with strenuous exercise training. Using the female cynomolgus monkey (Macaca fascicularis), we documented changes in menstrual cyclicity and patterns of LH, FSH, estradiol, and progesterone secretion as the animals developed exercise-induced amenorrhea. As monkeys gradually increased running to 12.3 +/- 0.9 km/day, body weight did not change significantly although food intake remained constant. The time spent training until amenorrhea developed varied widely among animals (7-24 months; mean = 14.3 +/- 2.2 months) and was not correlated with initial body weight, training distance, or food intake. Consistent changes in function of the reproductive axis occurred abruptly, one to two menstrual cycles before the development of amenorrhea. These included significant declines in plasma reproductive hormone concentrations, an increase in follicular phase length, and a decrease in luteal phase progesterone secretion. These data document a high level of interindividual variability in the development of exercise-induced reproductive dysfunction, delineate the progression of changes in reproductive hormone secretion that occur with exercise training, and illustrate an abrupt transition from normal cyclicity to an amenorrheic state in exercising individuals, that is not necessarily associated with weight loss.
Reproduction trends and the emergence of moral panic.
Hanmer, J
1987-01-01
Are we witnessing a moral panic or a moral evaluation in the responses to the new reproductive technologies? Locating women in reproductive technology is a particularly powerful way into a discussion of values and consequences, intended or unintended. Twelve areas are isolated for discussion beginning with issues of definition and location: What is reproductive and genetic engineering? and How does human reproduction fit into bio-technological developments generally? Next issues are raised about how the new developments are being shaped ideologically and how they are being promoted by the state. A series of legal issues affecting women, men, children, embryos and fetuses follow. The focus then shifts to the way women are ideologically constructed: Why is there an assumption that woman = mother, and mother = heterosexual married or stable cohabiting woman?--and socially controlled: Why assume technological change in human reproductive processes means the basic subordination of women to men will not alter? The usefulness of the new technologies in relieving involuntary childlessness is then queried which leads on to a questioning of whether these developments are qualitatively different from other technologies used in human reproduction. Futuristic concerns such as the importance of the male pregnancy and the social consequences of fully medicalising human reproduction are raised. The last area to be considered is protest by women and suggested alternative approaches to increase the social visibility and recognition of the needs and interest of women in the current and potential use of the new medical and scientific developments.
Zhang, Shuang-Shuang; Yang, Hongxing; Ding, Lan; Song, Ze-Ting; Ma, Hong; Chang, Fang; Liu, Jian-Xiang
2017-05-01
High temperatures have a great impact on plant reproductive development and subsequent fruit and seed set, but the underlying molecular mechanisms are not well understood. We used transcriptome profiling to investigate the effect of heat stress on reproductive development of Arabidopsis thaliana plants and observed distinct response patterns in vegetative versus reproductive tissues. Exposure to heat stress affected reproductive developmental programs, including early phases of anther/ovule development and meiosis. Also, genes participating in the unfolded protein response (UPR) were enriched in the reproductive tissue-specific genes that were upregulated by heat. Moreover, we found that the UPR-deficient bzip28 bzip60 double mutant was sensitive to heat stresses and had reduced silique length and fertility. Comparison of heat-responsive wild type versus bzip28 bzip60 plants identified 521 genes that were regulated by bZIP28 and bZIP60 upon heat stress during reproductive stages, most of which were noncanonical UPR genes. Chromatin immunoprecipitation coupled with high-throughput sequencing analyses revealed 133 likely direct targets of bZIP28 in Arabidopsis seedlings subjected to heat stress, including 27 genes that were also upregulated by heat during reproductive development. Our results provide important insights into heat responsiveness in Arabidopsis reproductive tissues and demonstrate the protective roles of the UPR for maintaining fertility upon heat stress. © 2017 American Society of Plant Biologists. All rights reserved.
Melatonin and the circadian system: contributions to successful female reproduction.
Reiter, Russel J; Tamura, Hiroshi; Tan, Dun Xian; Xu, Xiao-Ying
2014-08-01
To summarize the role of melatonin and circadian rhythms in determining optimal female reproductive physiology, especially at the peripheral level. Databases were searched for the related English-language literature published up to March 1, 2014. Only papers in peer-reviewed journals are cited. Not applicable. Not applicable. Melatonin treatment, alterations of the normal light:dark cycle and light exposure at night. Melatonin levels in the blood and in the ovarian follicular fluid and melatonin synthesis, oxidative damage and circadian rhythm disturbances in peripheral reproductive organs. The central circadian regulatory system is located in the suprachiasmatic nucleus (SCN). The output of this master clock is synchronized to 24 hours by the prevailing light-dark cycle. The SCN regulates rhythms in peripheral cells via the autonomic nervous system and it sends a neural message to the pineal gland where it controls the cyclic production of melatonin; after its release, the melatonin rhythm strengthens peripheral oscillators. Melatonin is also produced in the peripheral reproductive organs, including granulosa cells, the cumulus oophorus, and the oocyte. These cells, along with the blood, may contribute melatonin to the follicular fluid, which has melatonin levels higher than those in the blood. Melatonin is a powerful free radical scavenger and protects the oocyte from oxidative stress, especially at the time of ovulation. The cyclic levels of melatonin in the blood pass through the placenta and aid in the organization of the fetal SCN. In the absence of this synchronizing effect, the offspring may exhibit neurobehavioral deficits. Also, melatonin protects the developing fetus from oxidative stress. Melatonin produced in the placenta likewise may preserve the optimal function of this organ. Both stable circadian rhythms and cyclic melatonin availability are critical for optimal ovarian physiology and placental function. Because light exposure after darkness onset at night disrupts the master circadian clock and suppresses elevated nocturnal melatonin levels, light at night should be avoided. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Lake trout restoration in the Great Lakes: stock-size criteria for natural reproduction
Selgeby, James H.; Bronte, Charles R.; Brown, Edward H.; Hansen, Michael J.; Holey, Mark E.; VanAmberg, Jan P.; Muth, Kenneth M.; Makauskas, Daniel B.; Mckee, Patrick; Anderson, David M.; Ferreri, C. Paola; Schram, Stephen T.
1995-01-01
We examined the question of whether the lake trout restoration program in the Great Lakes has developed brood stocks of adequate size to sustain natural reproduction. Stock size criteria were developed from areas of the Great Lakes where natural reproduction has been successful (defined as detection of age-1 or older recruits by assessment fishing). We contrasted them with stocks in areas with no natural reproduction. Based on the relative abundance of spawners measured in the fall and the presence or absence of natural reproduction in 24 areas of the Great Lakes, we found three distinct sets of lake trout populations. In seven areas of successful natural reproduction, the catch-per-unit-effort (CPE) of spawners ranged from 17 to 135 fish/305 m of gillnet. Stock sizes in these areas were used as a gauge against which stocks in other areas were contrasted. We conclude that stock densities of 17-135 fish/305 m of gill net are adequate for natural reproduction, provided that all other requirements are met. No natural reproduction has been detected in seven other areas, where CPEs of spawners ranged from only 3 to 5 fish/305 m. We conclude that spawning stocks of only 3-5 fish/305 m of net are inadequate to develop measurable natural reproduction. Natural reproduction has also not been detected in ten areas where CPEs of spawners ranged from 43 to 195 fish/305 m of net. We conclude that spawning stocks in these ten areas were adequate to sustain natural reproduction, but that some factor other than parental stock size prevented recruitment of wild lake trout.
Webinar Presentation: Effects of Phthalates on the Female Reproductive System
This presentation, Effects of Phthalates on the Female Reproductive System, was given at the NIEHS/EPA Children's Centers 2015 Webinar Series: Phthalates in the Diet and in our Homes held on June 10, 2015.
K Chandra, Amar; Sengupta, Pallav; Goswami, Haimanti; Sarkar, Mahitosh
2012-05-01
Calcium is essential for functioning of different systems including male reproduction. However, it has also been reported as chemo-castrative agent. The study has been undertaken to elucidate the effect of excessive dietary calcium on male reproductive system in animals with possible action. Adult male healthy rats fed CaCl(2) at different doses (0.5, 1.0 and 1.5 g%) in diet for 13 and 26 days to investigate reproductive parameters as well as the markers of oxidative stress. Significant alteration was found (P < 0.05) in testicular and accessory sex organs weight, epididymal sperm count, testicular steroidogenic enzyme (Δ(5) 3β-HSD and 17β-HSD) activities, serum testosterone, LH, FSH, LPO, activities of antioxidant enzymes, testicular histoarchitecture along with adrenal Δ(5) 3β-HSD activity with corticosterone level in dose- and time-dependent manner. Overall observations suggest that excessive dietary calcium enhances the generation of free-radicals resulting in structural and functional disruption of male reproduction.
Saad, Ramadan A; Mahmoud, Yomna I
2014-12-01
Ursodeoxycholic acid is the most widely used drug for treating cholestatic liver diseases. However, its effect on the male reproductive system alterations associated with cholestasis has never been studied. Thus, this study aimed to investigate the effect of ursodeoxycholic acid on cholestasis-induced alterations in the male reproductive system. Cholestasis was induced by bile duct ligation. Bile duct-ligated rats had higher cholestasis biomarkers and lower levels of testosterone, LH and FSH than did the Sham rats. They also had lower reproductive organs weights, and lower sperm motility, density and normal morphology than those of Sham rats. Histologically, these animals suffered from testicular tubular atrophy, interstitial edema, thickening of basement membranes, vacuolation, and depletion of germ cells. After ursodeoxycholic acid administration, cholestasis-induced structural and functional alterations were significantly ameliorated. In conclusion, ursodeoxycholic acid can ameliorate the reproductive complications of chronic cholestasis in male patients, which represents an additional benefit to this drug. Copyright © 2014 Elsevier Inc. All rights reserved.
Huang, Hong Lan; Zhang, Lu; Jia, Li Ming; Liang, Yue-Long; Cai, Jun Huo
2018-04-01
To examine the reproduction fitness coefficients and individual-level fitness of Toona ciliata var. pubescens, their sexual reproduction and natural regeneration were investigated during 2006-2016, with four natural populations in Jiulianshan National Reserve as test objects. The results showed that there were only 2-10 trees for the natural populations of T. ciliata var. pubescens with a small initial number of fruiting plants (3-9 trees), which were from the initial fruiting plants or their first/second generation. The sexual reproduction of these isolated populations were significantly different, and their seed production capacities tended to decline over time. With the maturing of communities, soil seed banks and seed germinations were extremely poor, and the number of trees that could be growing to mature stage was nearly zero. The optimum maturity age of T. ciliata var. pubescens was about 40 a, and the fitness coefficients (2.0-2.8) rapidly increased in early development stage, but then was sharply reduced (0.3-0.5), and then gradually dropped to almost 0. There were significant differences in the fitness at individual level (0-14 tree·cm -2 ) among different populations, but their values were low (close to zero). Based on the existing reproduction rate, the actual values of sexual reproduction and regeneration fitness were much lower than the predicted ones. Due to the low level of genetic fitness, the sexual reproductive ability of different populations all showed decreasing trends. The natural sexual regeneration ability tended to decline, while the fitness of T. ciliata var. pubescens further decreased. All those factors suggested higher investment risks. Therefore, the systems of sexual reproduction became unbalanced and deteriorating. We proposed that more studies, including breeding mating, pollination, seed setting, and genetic diversity evaluation, are needed. Moreover, we should provide suitable forest environment through cleaning up litter in the fruiting stage and applying appropriate thinning during the transition period from seedling to young tree growth.
The role of essential trace elements in embryonic and fetal development in livestock.
Hostetler, Chris E; Kincaid, Ron L; Mirando, Mark A
2003-09-01
This review addresses the concept that essential trace minerals play a vital role in many enzymatic and metabolic pathways that are critical for conceptus development during pregnancy in livestock species. The conceptus relies entirely on the maternal system for a sufficient supply of trace minerals and other nutrients needed for normal development. If this supply is inadequate, growth and/or health of the conceptus can be affected adversely, and many of these effects carry over into the neonatal period. Information, accumulated in our laboratory and presented herein, indicates that zinc, copper and manganese are among the trace minerals that have the greatest impact on reproduction. For example, levels of zinc, copper and manganese were several fold greater in the conceptus than in other reproductive tissues, indicating that the conceptus preferentially accumulates these minerals, an action that may be important for conceptus development, growth and survival. Moreover, some recent results indicate that increasing the biological availability of zinc, copper and manganese, by attachment to short peptide chains (i.e., proteinated trace minerals) can enhance reproductive performance of swine. Mineral concentrations in conceptuses from female pigs consuming proteinated trace minerals were greater than those from females that consumed only inorganic mineral salts. Elucidating the mechanisms whereby conceptus development and survival are enhanced by essential trace minerals may lead to development of specific feeding programs to increase the number and health of offspring at parturition, thereby allowing for further improvements in production efficiency in animal agriculture.
Keeper, D M; Kerrisk, K L; House, J K; Garcia, S C; Thomson, P
2017-09-01
To determine the management practices utilised in automatic milking systems (AMS) that affect reproductive management and performance and how these compare with the management practices used in regionally proximal conventional milking systems (CMS). This study examined demographic and management data from AMS and CMS dairy farms through a survey, with a specific focus on reproductive management procedures. Overall, responses from AMS and CMS dairy farms showed little difference in terms of respondent demographics, farm size, herd structure and most farm management strategies. AMS dairies were more likely to use activity meters or other electronic oestrus detection aids than CMS dairies (P < 0.001) and were also more likely to have changed to electronic recording systems (P = 0.007). Although many respondents indicated that they used key monitoring parameters to assess reproductive performance (e.g. days in milk, conception vs pregnancy rate etc.), the format of responses varied significantly, indicating a relatively widespread (among the respondents) lack of knowledge regarding the meaning and usage of some of these common parameters/terminology. Ultimately, reproductive management practices of AMS dairies were largely similar to those of CMS dairies, indicating that such practices can be implemented in a practical sense, even though the resultant reproductive performance is not yet understood. Understanding that the key reproductive management strategies do not need to change vastly is important to ensure that new adoptees are well informed. Further work is needed to objectively measure AMS performance to increase the knowledge base and generate the confidence that will facilitate further adoption of this innovation. © 2017 Australian Veterinary Association.
[A list and analysis of reproductive medicine periodicals indexed in MEDLINE in 2006].
Xia, Xin-yi; Huang, Yu-feng; Pan, Lian-jun; Shang, Xue-jun
2006-07-01
MEDLINE established by National Library of Medicine (NLM), USA, is the most commonly used biomedical literature retrieval system, whose indexed literature generally represents the top of the medical world. Of the total number of 4959 journals listed in the Lists of Journals Indexed in MEDLINE (2006) published by NLM, 46 are periodicals of reproductive medicine, mainly including andrology, fertility, and sterility. Researchers of reproductive medicine should be familiar with the journals indexed in MEDLINE, closely follow their published frontier researches in this field, and consciously contribute to them in English. Editors of reproductive medicine journals should endeavour to have their journals included in such internationally authoritative systems as MEDLINE, SCI, etc by publishing them in English in compliance with international standards. This article presents a list of the reproductive medicine periodicals indexed in MEDLINE (2006) together with a brief analysis, which is meant to help researchers in reproductive medicine, andrology and other relevant fields with their contribution, subscription, reading and retrieving, as well as to share some more knowledge about MEDLINE and its indexed journals with Chinese editors of reproductive medicine journals.
Evolution of the asexual queen succession system and its underlying mechanisms in termites.
Matsuura, Kenji
2017-01-01
One major advantage of sexual reproduction over asexual reproduction is its promotion of genetic variation, although it reduces the genetic contribution to offspring. Queens of social insects double their contribution to the gene pool, while overuse of asexual reproduction may reduce the ability of the colony to adapt to environmental stress because of the loss of genetic diversity. Recent studies have revealed that queens of some termite species can solve this tradeoff by using parthenogenesis to produce the next generation of queens and sexual reproduction to produce other colony members. This reproductive system, known as asexual queen succession (AQS), has been identified in the subterranean termites Reticulitermes speratus, Reticulitermes virginicus and Reticulitermes lucifugus and in the Neotropical higher termites Embiratermes neotenicus and Cavitermes tuberosus The studies presented here have uncovered the unusual modes of reproduction in termites and have aimed to identify their underlying mechanisms. The study of AQS, the mixed use of sexual and asexual reproduction, is of fundamental importance as it may provide a key to solve the evolutionary paradox of sex. © 2017. Published by The Company of Biologists Ltd.
Over the past decade, our research team at the US EPA Mid-Continent Ecology Division has employed systems biology approaches to examine and understand impacts of environmental contaminants on fish reproduction. Our systems biology approach is one in which iterations of model cons...
Pinto, P; Velez, Z; Sousa, C; Santos, S; Andrade, A; Alvarado, M V; Felip, A; Zanuy, S; Canário, A V M
2017-09-01
The neuropeptide galanin (Gal) is a putative factor regulating puberty onset and reproduction through its actions on the pituitary. The present study investigated the pituitary responsiveness to galanin and the patterns of galanin receptors (Galrs) expression throughout the reproductive cycle of two years old male European sea bass (Dicentrarchus labrax), an important aquaculture species. Quantitative analysis of pituitary and hypothalamus transcript expression of four galr subtypes revealed differential regulation according to the testicular developmental stage, with an overall decrease in expression from the immature stage to the mid-recrudescence stage. Incubation of pituitary cells with mammalian 1-29Gal peptide induced significant changes in cAMP concentration, with sensitivities that varied according to the testicular development stages. Furthermore 1-29Gal was able to stimulate both follicle stimulating hormone (Fsh) and luteinizing hormone (Lh) release from pituitary cell suspensions. The magnitude of the effects and effective concentrations varied according to reproductive stage, with generalized induction of Fsh and Lh release in animals sampled in January (full spermiation). The differential expression of galrs in pituitary and hypothalamus across the reproductive season, together with the differential effects of Gal on gonadotropins release in vitro strongly suggests the involvement of the galaninergic system in the regulation the hypothalamus-pituitary-gonad axis of male sea bass. This is to our knowledge the first clear evidence for the involvement of galanin in the regulation of reproduction in non-mammalian vertebrates. Copyright © 2017 Elsevier Inc. All rights reserved.
Sexual and reproductive rights and the human rights agenda: controversial and contested.
Nowicka, Wanda
2011-11-01
In this paper I share some of my experience and observations, as an advocate for women's rights, of the last 20 years of struggles for sexual and reproductive health and rights, carried out in many key places where these issues have been debated and decided. I do not aspire to be comprehensive about the current status of human rights related to sexuality and reproduction. Given that my expertise is of a practical (rather than theoretical) nature, the complexity of the topic and contradictory events with regard to it, which take place almost everyday, I will highlight some selected achievements and setbacks in this area, particularly regarding abortion rights. I will provide examples of how human rights related to sexual and reproductive health have been addressed in UN policy-setting bodies, such as the Commission on the Status of Women and Commission on Population and Development, as well as in the UN human rights system such as Treaty Monitoring Bodies and Human Rights Council. Given my work with European institutions, I provide examples of important decisions by the Council of Europe and the European Court of Human Rights. Lastly, I discuss growing opposition to a progressive human rights agenda and the universality of human rights. Despite significant successes, sexual and reproductive rights will long remain controversial and contested. Hence, it is crucial to try to find new ways to engage and new partners to work with. Copyright © 2011 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
Scoppettone, Gayton G.; Rissler, Peter H.; Fabes, Mark C.; Shea, Sean P.
2015-01-01
Fishes of the Truckee River basin (California and Nevada) evolved in an aquatic system that has been episodically diminished by extended drought. For potamodromous species, such as the endangered Cui-ui endemic to Pyramid Lake, Nevada, prehistoric episodic severe drought presumably led to periods of failed reproduction due to restricted access to spawning habitat. The response of the Cui-ui population to more recent failed reproduction caused by anthropogenic activity was studied to learn how to manage this species through periods of spawning disruption. Adult Cui-ui survival averaged 91% and 89% for females and males, respectively, in drought years when spawning migrations were either precluded or few fish migrated because of no or low stream flow. In each of 2 years when stream access was precluded, the adult survival was nearly 100% suggesting that Cui-ui survival is extended in the absence of a spawning migration. Survival averaged 62% and 60% for females and males, respectively, in years of spawning migrations. Strong predominant year-classes developed in the year immediately following a period of failed reproduction, indicating the species’ capacity for population rebound. Year-class predominance persisted for 6–10 years and through years of low survival associated with migration years, and this predominance is probably due, in part, to a diverse age at maturity. Contemporary water diversions from the Truckee River provided the opportunity to study the response of the Cui-ui population to years of failed reproduction. A projected drier Truckee River basin associated with global climate change will test the Cui-ui’s adaptive capacity to endure periods of reproductive failure. This study is aimed at assisting Cui-ui managers in conserving the species in this highly regulated and changing system. The study also adds insight into the prehistoric population dynamics of a potamodromous species in the arid western United States subject to wide fluctuations in annual precipitation and water availability
Adipose tissue represents an important and understudied component of the endocrine system. Recent evidence suggests that endocrine-disrupting chemicals (EDCs) may be able to alter lipid development (e.g., adipogenesis) and/or the balance of lipid metabolism. The environmentally a...
Molecular structure and diversity of PBAN/Pyrokinin family peptides in ants
USDA-ARS?s Scientific Manuscript database
Neuropeptides are the largest group of insect hormones. They are produced in the central and peripheral nervous systems and affect insect development, reproduction, feeding and behavior. A variety of neuropeptide families have been identified in insects. One of these families is the PBAN/Pyrokinin f...
Metamorphosis of the amphibian tadpole is a thyroid hormone (TH)-dependent developmental process. For this reason, the tadpole is considered to be an ideal bioassay system to identify disruption of thyroid function by environmental contaminants. Here we provide an in-depth review...
Scientists are increasingly aware of the adverse effects of environmental contaminants, including their ability to alter the normal development and reproduction of wildlife species by modifying the endocrine system. Female mosquitofish living downstream of a paper mill plant loca...
Aquatic organisms are continuously exposed to complex mixtures of chemicals, many of which can interfere with their endocrine system, resulting in impaired reproduction, development or survival, among others. In order to analyze the effects and mechanisms of action of estrogen...
USDA-ARS?s Scientific Manuscript database
Pseudorabies virus (PRV) is a neurotropic alphaherpesvirus that produces fatal encephalitis in newborn pigs, respiratory disorders in fattening pigs and reproductive failure in sows. Following primary infection of the respiratory tract, PRV can develop into a systemic infection with dispersion of t...
Career and Vocational Education. Concepts of Health Management System.
ERIC Educational Resources Information Center
Larson, Curtis G.; Fiedler, Beatrice
This curriculum guide is designed to assist students in developing the ability to understand the many aspects of personal/social/mental health. It emphasizes student performance objectives in physical well-being, disease, reproduction, heredity, mental health and aging. It is also designed to assist the local teacher with organization and…
ERIC Educational Resources Information Center
Marks, Gary N.
2009-01-01
Modernization theory argues that, as societies industrialize and further develop, the influence of social background and other ascribed characteristics on educational and socioeconomic outcomes declines, while achievement in the education system becomes more important. The purpose of this research is to investigate propositions derived from…
Evidence-based recommendations to improve reproductive healthcare for incarcerated women.
Knittel, Andrea; Ti, Angeline; Schear, Sarah; Comfort, Megan
2017-09-11
Purpose The purpose of this paper is to describe standards for evidence-based reproductive healthcare for incarcerated women. Design/methodology/approach The literature on reproductive healthcare in the US criminal justice system and recommendations from professional organizations were reviewed and critical areas of concern were identified. Within these areas, studies and expert opinion were synthesized and policy recommendations were formulated through an iterative process of group discussion and document revision. This brief specifically addresses women's incarceration in the USA, but the recommendations are grounded in a human rights framework with global relevance. Findings Women who are incarcerated have health needs that are distinct from those of men, and there is a clear need for gender-responsive reproductive healthcare within the criminal justice system. This brief identifies five core domains of reproductive healthcare: routine screening, menstruation-related concerns, prenatal and postpartum care, contraception and abortion, and sexually transmitted infections. The recommendations emphasize the continuity between the criminal justice system and the community, as well as the dignity and self-determination of incarcerated women. Originality/value This brief provides a unique synthesis of the available evidence with concrete recommendations for improving the reproductive healthcare for incarcerated women.
Reproductive Physiology of Marsupials
ERIC Educational Resources Information Center
Sharman, G. B.
1970-01-01
Describes some unique features of marsupial reproduction which include (1) chromosomal sex determination, (2) reproductive system, (3) birth, (4) location, and (5) embryonic diapause. These features suggest that viviparity evolved separately in eutherian and marsupial stocks after their derivation from a common oviparous ancestor. Bibliography.…
Multigeneration reproduction studies are used to characterize parental and offspring systemic toxicity, as well as reproductive toxicity of pesticides, industrial chemicals and pharmaceuticals. Results from 329 multigeneration studies on 316 chemicals have been digitized into sta...
Reproduction of Epstein-Barr Virus Infection and Pathogenesis in Humanized Mice
2014-01-01
Epstein-Barr virus (EBV) is etiologically associated with a variety of diseases including lymphoproliferative diseases, lymphomas, carcinomas, and autoimmune diseases. Humans are the only natural host of EBV and limited species of new-world monkeys can be infected with the virus in experimental conditions. Small animal models of EBV infection, required for evaluation of novel therapies and vaccines for EBV-associated diseases, have not been available. Recently the development of severely immunodeficient mouse strains enabled production of humanized mice in which human immune system components are reconstituted and express their normal functions. Humanized mice can serve as infection models for human-specific viruses such as EBV that target cells of the immune system. This review summarizes recent studies by the author's group addressing reproduction of EBV infection and pathogenesis in humanized mice. PMID:24605074
Haslegrave, Marianne
2013-11-01
Since the 1994 International Conference on Population and Development (ICPD) in Cairo placed reproductive health and rights firmly on the international agenda, civil society and other advocates have worked ceaselessly to ensure that they remain central to women's empowerment and have taken all opportunities to expand the framework to include sexual health and rights. When the development process changed with the introduction of the Millennium Development Goals (MDGs) in 2000, sexual and reproductive health and rights were excluded, and only in 2007 was universal access to reproductive health added back in. In 2014 and 2015, the future of ICPD Beyond 2014, the MDGs and the post-2015 development framework will be decided, following consultations and meetings across the globe. This paper takes stock of the key influences on efforts to achieve the ICPD agenda and summarises the past, current and planned future events, reports and processes between 1994 and 2014, leading up to the determination of the post-2015 development framework and sustainable development goals. It concludes that the one thing we cannot afford to allow is what happened with the MDGs in 2000. We must not leave the room empty-handed, but must instead ensure the inclusion of sexual and reproductive health and rights as a priority under a new health goal. Copyright © 2013 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
Why acquiesce? Worker reproductive parasitism in the Eastern honeybee (Apis cerana).
Holmes, M J; Tan, K; Wang, Z; Oldroyd, B P; Beekman, M
2014-05-01
Most societies are vulnerable to rogue individuals that pursue their own interests at the expense of the collective entity. Societies often protect themselves from selfish behaviour by 'policing', thereby enforcing the interests of the collective over those of individuals. In insect societies, for example, selfish workers can activate their ovaries and lay eggs, exploiting the collective brood rearing system for individual benefit. Policing, usually in the form of oophagy of worker-laid eggs, controls selfish behaviour. Importantly, once an effective system of policing has evolved, the incentive for personal reproduction is lost, and 'reproductive acquiescence' in which ovary activation is rare or absent is predicted to evolve. Studies of social Hymenoptera have largely supported the prediction of worker 'acquiescence'; workers of most species where policing is well developed have inactive ovaries. However, the eastern honeybee Apis cerana appears to be an exception. A. cerana colonies are characterized by highly efficient policing, yet about 5% of workers have active ovaries, even when a queen is present. This suggests that the evolution of acquiescence is incomplete in A. cerana. We regularly sampled male eggs and pupae from four A. cerana colonies. Workers had high levels of ovary activation overall (11.7%), and 3.8% of assignable male eggs and 1.1% of assignable male pupae were worker-laid. We conclude that workers with active ovaries lay their eggs, but these rarely survive to pupation because of intense policing. We then used our findings as well as previously published data on A. cerana and A. mellifera to redo the meta-analysis on which reproductive acquiescence theory is based. Including data on both species did not affect the relationship between effectiveness of policing and levels of worker reproduction. Their inclusion did, however, seriously weaken the relationship between relatedness among workers and levels of worker reproduction. Our work thus suggests that relatedness among workers does not affect the probability that workers will attempt to reproduce, but that it is coercion by peers that limits worker reproduction. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.
Steinberg, Rebecca M.; Walker, Deena M.; Juenger, Thomas E.; Woller, Michael J.; Gore, Andrea C.
2009-01-01
Perinatal exposures to endocrine-disrupting chemicals such as polychlorinated biphenyls (PCBs) can cause latent effects on reproductive function. Here, we tested whether PCBs administered during late pregnancy would compromise reproductive physiology in both the fetally-exposed female offspring (F1 generation), as well as in their female offspring (F2 generation). Pregnant Sprague-Dawley rats were treated with the PCB mixture Aroclor (A) 1221 (0, 0.1, 1 or 10 mg/kg) on embryonic days 16 and 18. Somatic and reproductive development of F1 and their F2 female offspring were monitored, including ages of eye opening, pubertal landmarks, and serum reproductive hormones. The results showed that low doses of A1221 given during this critical period of neuroendocrine development caused differential effects of A1221 on F1 and F2 female rats. In both generations, litter sex ratio was skewed towards females. In the F1 generation, additional effects were found including a significant alteration of serum luteinizing hormone (LH) in the 1 mg/kg A1221 group. The F2 generation showed more profound alterations, particularly with respect to fluctuations in hormones and reproductive tract tissues across the estrous cycle. On proestrus, the day of the preovulatory GnRH/gonadotropin surge, F2 females whose mothers had been perinatally exposed to A1221 exhibited substantially suppressed LH and progesterone concentrations, and correspondingly smaller uterine and ovarian weights on estrus, compared to F2 decendants of control rats. These latter changes suggest a dysregulation of reproductive physiology. Thus, low levels of exposure to PCBs during late fetal development cause significant consequences on the maturation and physiology of two generations of female offspring. These findings have implications for reproductive health and fertility of wildlife and humans. PMID:18305224
Zhang, Dapeng; Xiong, Huiling; Mennigen, Jan A; Popesku, Jason T; Marlatt, Vicki L; Martyniuk, Christopher J; Crump, Kate; Cossins, Andrew R; Xia, Xuhua; Trudeau, Vance L
2009-06-05
Many vertebrates, including the goldfish, exhibit seasonal reproductive rhythms, which are a result of interactions between external environmental stimuli and internal endocrine systems in the hypothalamo-pituitary-gonadal axis. While it is long believed that differential expression of neuroendocrine genes contributes to establishing seasonal reproductive rhythms, no systems-level investigation has yet been conducted. In the present study, by analyzing multiple female goldfish brain microarray datasets, we have characterized global gene expression patterns for a seasonal cycle. A core set of genes (873 genes) in the hypothalamus were identified to be differentially expressed between May, August and December, which correspond to physiologically distinct stages that are sexually mature (prespawning), sexual regression, and early gonadal redevelopment, respectively. Expression changes of these genes are also shared by another brain region, the telencephalon, as revealed by multivariate analysis. More importantly, by examining one dataset obtained from fish in October who were kept under long-daylength photoperiod (16 h) typical of the springtime breeding season (May), we observed that the expression of identified genes appears regulated by photoperiod, a major factor controlling vertebrate reproductive cyclicity. Gene ontology analysis revealed that hormone genes and genes functionally involved in G-protein coupled receptor signaling pathway and transmission of nerve impulses are significantly enriched in an expression pattern, whose transition is located between prespawning and sexually regressed stages. The existence of seasonal expression patterns was verified for several genes including isotocin, ependymin II, GABA(A) gamma2 receptor, calmodulin, and aromatase b by independent samplings of goldfish brains from six seasonal time points and real-time PCR assays. Using both theoretical and experimental strategies, we report for the first time global gene expression patterns throughout a breeding season which may account for dynamic neuroendocrine regulation of seasonal reproductive development.
Mennigen, Jan A.; Popesku, Jason T.; Marlatt, Vicki L.; Martyniuk, Christopher J.; Crump, Kate; Cossins, Andrew R.; Xia, Xuhua; Trudeau, Vance L.
2009-01-01
Background Many vertebrates, including the goldfish, exhibit seasonal reproductive rhythms, which are a result of interactions between external environmental stimuli and internal endocrine systems in the hypothalamo-pituitary-gonadal axis. While it is long believed that differential expression of neuroendocrine genes contributes to establishing seasonal reproductive rhythms, no systems-level investigation has yet been conducted. Methodology/Principal Findings In the present study, by analyzing multiple female goldfish brain microarray datasets, we have characterized global gene expression patterns for a seasonal cycle. A core set of genes (873 genes) in the hypothalamus were identified to be differentially expressed between May, August and December, which correspond to physiologically distinct stages that are sexually mature (prespawning), sexual regression, and early gonadal redevelopment, respectively. Expression changes of these genes are also shared by another brain region, the telencephalon, as revealed by multivariate analysis. More importantly, by examining one dataset obtained from fish in October who were kept under long-daylength photoperiod (16 h) typical of the springtime breeding season (May), we observed that the expression of identified genes appears regulated by photoperiod, a major factor controlling vertebrate reproductive cyclicity. Gene ontology analysis revealed that hormone genes and genes functionally involved in G-protein coupled receptor signaling pathway and transmission of nerve impulses are significantly enriched in an expression pattern, whose transition is located between prespawning and sexually regressed stages. The existence of seasonal expression patterns was verified for several genes including isotocin, ependymin II, GABAA gamma2 receptor, calmodulin, and aromatase b by independent samplings of goldfish brains from six seasonal time points and real-time PCR assays. Conclusions/Significance Using both theoretical and experimental strategies, we report for the first time global gene expression patterns throughout a breeding season which may account for dynamic neuroendocrine regulation of seasonal reproductive development. PMID:19503831
Dynamics of asexual reproduction in planarians
NASA Astrophysics Data System (ADS)
Schoetz, Eva-Maria; Lincoln, Bryan; Quinodoz, Sofia
2011-03-01
Planaria research is experiencing a resurgence due to the development of molecular tools, the Planarian genome project and database resources. Despite the resulting progress in planarian biology research, an extensive study of their physical properties remains to be undertaken. We developed a method to collect a large amount of data on the dynamics of clonal reproduction in the freshwater planarian S.mediterranea. The capability of planarians to regenerate an entire organism from a minuscule body part is based on a homogeneously distributed stem cell population that comprises 25-30% of all cells. Due to this stem cell contingent, planarians can reproduce spontaneously by dividing into a larger head and a smaller tail piece, which then will rebuild the missing body parts, including a central nervous system, within about a week. Time-lapse imaging allows us to characterize the fission process in detail, revealing the stages of the process as well as capturing the nature of the rupture itself. A traction force measurement setup is being developed to allow us to quantify the forces planarians exert on the substrate during reproduction, a macroscopic analog to the Traction Force Microscopy setups used to determine local cellular forces. We are particularly interested in the molecular processes during division and the interplay between tissue mechanics and cell signaling.
Human infertility: are endocrine disruptors to blame?
Marques-Pinto, André; Carvalho, Davide
2013-01-01
Over recent decades, epidemiological studies have been reporting worrisome trends in the incidence of human infertility rates. Extensive detection of industrial chemicals in human serum, seminal plasma and follicular fluid has led the scientific community to hypothesise that these compounds may disrupt hormonal homoeostasis, leading to a vast array of physiological impairments. Numerous synthetic and natural substances have endocrine-disruptive effects, acting through several mechanisms. The main route of exposure to these chemicals is the ingestion of contaminated food and water. They may disturb intrauterine development, resulting in irreversible effects and may also induce transgenerational effects. This review aims to summarise the major scientific developments on the topic of human infertility associated with exposure to endocrine disruptors (EDs), integrating epidemiological and experimental evidence. Current data suggest that environmental levels of EDs may affect the development and functioning of the reproductive system in both sexes, particularly in foetuses, causing developmental and reproductive disorders, including infertility. EDs may be blamed for the rising incidence of human reproductive disorders. This constitutes a serious public health issue that should not be overlooked. The exposure of pregnant women and infants to EDs is of great concern. Therefore, precautionary avoidance of exposure to EDs is a prudent attitude in order to protect humans and wildlife from permanent harmful effects on fertility. PMID:23985363
NASA Astrophysics Data System (ADS)
Burton, Jason C.; Wang, Shang; Behringer, Richard R.; Larina, Irina V.
2016-03-01
Infertility is a known major health concern and is estimated to impact ~15% of couples in the U.S. The majority of failed pregnancies occur before or during implantation of the fertilized embryo into the uterus. Understanding the mechanisms regulating development by studying mouse reproductive organs could significantly contribute to an improved understanding of normal development of reproductive organs and developmental causes of infertility in humans. Towards this goal, we report a three-dimensional (3D) imaging study of the developing mouse reproductive organs (ovary, oviduct, and uterus) using optical coherence tomography (OCT). In our study, OCT was used for 3D imaging of reproductive organs without exogenous contrast agents and provides micro-scale spatial resolution. Experiments were conducted in vitro on mouse reproductive organs ranging from the embryonic day 14.5 to adult stages. Structural features of the ovary, oviduct, and uterus are presented. Additionally, a comparison with traditional histological analysis is illustrated. These results provide a basis for a wide range of infertility studies in mouse models. Through integration with traditional genetic and molecular biology approaches, this imaging method can improve understanding of ovary, oviduct, and uterus development and function, serving to further contribute to our understanding of fertility and infertility.
Kaur, Satwant; Baynes, Alice; Lockyer, Anne E; Routledge, Edwin J; Jones, Catherine S; Noble, Leslie R; Jobling, Susan
2016-01-01
Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT) and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT), under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment.
Lockyer, Anne E.; Routledge, Edwin J.; Jones, Catherine S.; Noble, Leslie R.; Jobling, Susan
2016-01-01
Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT) and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT), under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment. PMID:27448327
Bontrager, Megan; Angert, Amy L
2016-01-01
Plant mating systems and geographic range limits are conceptually linked by shared underlying drivers, including landscape-level heterogeneity in climate and in species' abundance. Studies of how geography and climate interact to affect plant traits that influence mating system and population dynamics can lend insight to ecological and evolutionary processes shaping ranges. Here, we examined how spatiotemporal variation in climate affects reproductive output of a mixed-mating annual, Clarkia pulchella. We also tested the effects of population isolation and climate on mating-system-related floral traits across the range. We measured reproductive output and floral traits on herbarium specimens collected across the range of C. pulchella. We extracted climate data associated with specimens and derived a population isolation metric from a species distribution model. We then examined how predictors of reproductive output and floral traits vary among populations of increasing distance from the range center. Finally, we tested whether reproductive output and floral traits vary with increasing distance from the center of the range. Reproductive output decreased as summer precipitation decreased, and low precipitation may contribute to limiting the southern and western range edges of C. pulchella. High spring and summer temperatures are correlated with low herkogamy, but these climatic factors show contrasting spatial patterns in different quadrants of the range. Limiting factors differ among different parts of the range. Due to the partial decoupling of geography and environment, examining relationships between climate, reproductive output, and mating-system-related floral traits reveals spatial patterns that might be missed when focusing solely on geographic position. © 2016 Botanical Society of America.
ERIC Educational Resources Information Center
Miller, Deborah A.; Ellis, Edith B.
2006-01-01
Although critical to understanding human sexuality and reproductive physiology, the male and female reproductive anatomy is often minimally covered by teachers. For teachers and students alike, it is often an embarrassing topic to discuss. This activity allows students and teachers to identify the parts of both reproductive systems with little…