The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform
Justin D. Vidal - One of the best experts on this subject based on the ideXlab platform.
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Pathology of the Male and Female Reproductive System and Mammary Gland
Toxicologic Pathology for Non-Pathologists, 2019Co-Authors: Justin D. VidalAbstract:Test article–related effects on the Reproductive System can have a profound effect on pharmaceutical development. The Reproductive System has several unique features that differ from other organ Systems, including complex hormonal regulation; age-related changes such as puberty and Reproductive senescence; sex-specific characteristics such as spermatogenesis in the male and cyclicity in the Female; pronounced species differences; and evaluation occurring in the context of both repeated-dose general toxicology studies and stand-alone developmental and Reproductive toxicology (DART) studies. This requires a broad integration of toxicology and pathology with knowledge of Reproductive endocrinology, development, and comparative biology. This chapter reviews the pathology of the male and Female Reproductive System, including the mammary gland in Females. In males, the functional anatomy and physiology are reviewed. Key issues for toxicologists, including stage-aware evaluation of spermatogenesis and sexual maturity, are discussed. Background lesions for common laboratory animals, common test article–related lesions and reversibility, ancillary testing, and issues of relevance to humans are covered. The Female Reproductive System and mammary gland are covered in a similar format with important issues for toxicologists including Reproductive senescence and sexual maturity.
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Species Comparison of Postnatal Development of the Female Reproductive System.
Birth defects research, 2017Co-Authors: Susan B. Laffan, Lorraine M. Posobiec, Jenny E. Uhl, Justin D. VidalAbstract:The postnatal development of the Female Reproductive System in laboratory animals and humans is reviewed. To enable a meaningful species comparison of the developing Female Reproductive System, common definitions of developmental processes were established with a focus made on aspects that are similar across species. A species comparison of the key endocrine, morphologic, and functional (onset of ovarian cycles and ability to reproduce) features of postnatal development of the Female Reproductive System is provided for human, nonhuman primate, dog, rat, and also mouse, minipig, and rabbit where possible. Species differences in the timing and control of Female sexual maturation are highlighted. Additionally, a species comparison of the type and timing of Female Reproductive ovarian cycles was compiled. Human development provided the frame of reference, and then other common laboratory species were compared. The comparison has inherent challenges because the processes involved and sequence of events can differ greatly across species. Broad strokes were taken to assign a particular average age to an event and are to be used with caution. Methods of evaluation of postnatal Female Reproductive development in laboratory animals are discussed. Lastly, control rodent data from one of the author's laboratory on vaginal opening, first estrus, estrous cyclicity, and the histopathology involved with the developing Female rat and mouse are presented. The information provided in this review is intended to be a resource for the design and interpretation of juvenile animal toxicity testing and ultimately, the relevance of the data to characterize potential risks for women and girls. Birth Defects Research 110:163-189, 2018. © 2017 Wiley Periodicals, Inc.
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The Impact of Age on the Female Reproductive System.
Toxicologic pathology, 2016Co-Authors: Justin D. VidalAbstract:Evaluation of the Female Reproductive System in a general toxicity setting can be challenging for the toxicologic pathologist due to the cyclic nature of the estrous and menstrual cycles, timing of puberty and Reproductive senescence, and species differences. Age in particular can have a significant impact on the histologic appearance of the Female Reproductive System and create challenges when trying to distinguish test article-related findings from normal developmental or senescent changes. This review describes the key physiologic and histologic features of immaturity, the transition through puberty, sexual maturity, and Reproductive senescence in the Female Reproductive System, with an emphasis on practical applications for the toxicologic pathologist, and includes recommendations for distinguishing and documenting these developmental periods. Rats and cynomolgus monkeys are used as examples throughout with correlations to clinically observed end points to better aid the toxicologic pathologist in understanding how age may impact study interpretation.
Nel Roeleveld - One of the best experts on this subject based on the ideXlab platform.
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Pesticide exposure: the hormonal function of the Female Reproductive System disrupted?
Reproductive Biology and Endocrinology, 2006Co-Authors: Reini W Bretveld, Chris Mg Thomas, Paul Tj Scheepers, Gerhard A Zielhuis, Nel RoeleveldAbstract:Some pesticides may interfere with the Female hormonal function, which may lead to negative effects on the Reproductive System through disruption of the hormonal balance necessary for proper functioning. Previous studies primarily focused on interference with the estrogen and/or androgen receptor, but the hormonal function may be disrupted in many more ways through pesticide exposure. The aim of this review is to give an overview of the various ways in which pesticides may disrupt the hormonal function of the Female Reproductive System and in particular the ovarian cycle. Disruption can occur in all stages of hormonal regulation: 1. hormone synthesis; 2. hormone release and storage; 3. hormone transport and clearance; 4. hormone receptor recognition and binding; 5. hormone postreceptor activation; 6. the thyroid function; and 7. the central nervous System. These mechanisms are described for effects of pesticide exposure in vitro and on experimental animals in vivo . For the latter, potential effects of endocrine disrupting pesticides on the Female Reproductive System, i.e. modulation of hormone concentrations, ovarian cycle irregularities, and impaired fertility, are also reviewed. In epidemiological studies, exposure to pesticides has been associated with menstrual cycle disturbances, reduced fertility, prolonged time-to-pregnancy, spontaneous abortion, stillbirths, and developmental defects, which may or may not be due to disruption of the Female hormonal function. Because pesticides comprise a large number of distinct substances with dissimilar structures and diverse toxicity, it is most likely that several of the above-mentioned mechanisms are involved in the pathophysiological pathways explaining the role of pesticide exposure in ovarian cycle disturbances, ultimately leading to fertility problems and other Reproductive effects. In future research, information on the ways in which pesticides may disrupt the hormonal function as described in this review, can be used to generate specific hypotheses for studies on the effects of pesticides on the ovarian cycle, both in toxicological and epidemiological settings.
Elisabete Weiderpass - One of the best experts on this subject based on the ideXlab platform.
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malignant tumors of the Female Reproductive System
Safety and health at work, 2012Co-Authors: Elisabete WeiderpassAbstract: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.
O. A. Anurova - One of the best experts on this subject based on the ideXlab platform.
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Female Reproductive System tumors with Merkel cell phenotype
Russian Journal of Oncology, 2016Co-Authors: Seda O. Nikogosyan, T. Sh Tagibova, V. V. Kuznetsov, O. A. AnurovaAbstract:Diagnostics and treatment of Female Reproductive System tumors with Merkel cell phenotype, rare aggressive tumors with dismal prognosis, is under consideration in this article. Only 20 cases of Merkel cell vulvar carcinoma and 1 case of Merkel cell vagina cancer were described in the literature. Diagnostics must include immunohistochemical analysis, as expression of cytokeratine 20 proves to be the most typical factor. Polyomavirus infection is believed to be associated with the disease pathogenesis. No treatment standards were accepted due to the rarity of the disease. Considering the data on tumor radiosensitivity, the treatment must include radio- or chemoradiotherapy.
Reini W Bretveld - One of the best experts on this subject based on the ideXlab platform.
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Pesticide exposure: the hormonal function of the Female Reproductive System disrupted?
Reproductive Biology and Endocrinology, 2006Co-Authors: Reini W Bretveld, Chris Mg Thomas, Paul Tj Scheepers, Gerhard A Zielhuis, Nel RoeleveldAbstract:Some pesticides may interfere with the Female hormonal function, which may lead to negative effects on the Reproductive System through disruption of the hormonal balance necessary for proper functioning. Previous studies primarily focused on interference with the estrogen and/or androgen receptor, but the hormonal function may be disrupted in many more ways through pesticide exposure. The aim of this review is to give an overview of the various ways in which pesticides may disrupt the hormonal function of the Female Reproductive System and in particular the ovarian cycle. Disruption can occur in all stages of hormonal regulation: 1. hormone synthesis; 2. hormone release and storage; 3. hormone transport and clearance; 4. hormone receptor recognition and binding; 5. hormone postreceptor activation; 6. the thyroid function; and 7. the central nervous System. These mechanisms are described for effects of pesticide exposure in vitro and on experimental animals in vivo . For the latter, potential effects of endocrine disrupting pesticides on the Female Reproductive System, i.e. modulation of hormone concentrations, ovarian cycle irregularities, and impaired fertility, are also reviewed. In epidemiological studies, exposure to pesticides has been associated with menstrual cycle disturbances, reduced fertility, prolonged time-to-pregnancy, spontaneous abortion, stillbirths, and developmental defects, which may or may not be due to disruption of the Female hormonal function. Because pesticides comprise a large number of distinct substances with dissimilar structures and diverse toxicity, it is most likely that several of the above-mentioned mechanisms are involved in the pathophysiological pathways explaining the role of pesticide exposure in ovarian cycle disturbances, ultimately leading to fertility problems and other Reproductive effects. In future research, information on the ways in which pesticides may disrupt the hormonal function as described in this review, can be used to generate specific hypotheses for studies on the effects of pesticides on the ovarian cycle, both in toxicological and epidemiological settings.
