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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

The structure of the reproductive system in the male vervet monkey, Chlorocebus Aethiops, with special reference to spermatogenesis. /

Lebelo, Segolo Lucky. January 2007 (has links) (PDF)
Thesis (Ph. D. (Dept. of Medical Biosciences)--University of the Western Cape, 2007. / Includes bibliographical references (leaves 215-239).
22

Altered gene expression a mechanism of reproductive toxicity in zebrafish (Danio rerio) exposed to benzo[a]pyrene /

Hoffmann, Jennifer L. January 2004 (has links)
Thesis (Ph. D.)--Miami University, Dept. of Zoology, 2004. / Title from second page of PDF document. Includes bibliographical references (p. 116-127).
23

Desenvolvimento reprodutivo de ratos machos expostos ao fenvalerato in utero e lactação / Reproductive development of male rats exposed to fenvalerate in utero and lactation

Nassr, Azize Cristina Capelli 14 October 2005 (has links)
Orientador: Wilma De Grava Kempinas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T10:14:11Z (GMT). No. of bitstreams: 1 Nassr_AzizeCristinaCapelli_M.pdf: 10674778 bytes, checksum: 6e73e575f70e9f4c4cdd81eb7eac3586 (MD5) Previous issue date: 2005 / Resumo: o fenvalerato é um inseticida piretróide sintético usado na agricultura, pecuária e no controle de insetos domésticos, e seus efeitos reprodutivos são pouco conhecidos. Algunsestudos têm proposto que o fenvaleratoseja um desregulador endócrino,atuando como um estrógeno ambiental. Estudos realizados com ratos adultos expostos a determinados piretróides mostraram a redução do número de espermatozóides e das concentrações plasmáticas de testosterona. Sabendo-se que o sistema reprodutor masculino de ratos é mais sensível ao efeito de substâncias tóxicas durante as fases fetal e neonatal, o objetivo deste trabalho foi avaliar os possíveis efeitos tardios sobre o desenvolvimento reprodutivo na pré-puberdade (40 dias de idade), puberdade (60 dias) e maturidadesexual (90 dias), em ratos machos cujas mães foram expostas ao fenvalerato durante a prenhez e lactação. Adicionalmente,investigou-seo comportamentosexual, a fertilidadedos ratos adultos,a transferênciado fenvaleratodas mães para a prole,e a sua persistência no organismo dos descendentes machos. Para este estudo ratas prenhes (n=8) foram tratadas com fenvalerato técnico (96% de pureza), na dose diária de 40 mg/Kg, do 12° dia de prenhez até o final da lactação (período crítico de diferenciação do sistema reprodutor masculino da prole). Ratas controles (n=8) receberam óleo de milho (veículo), nas mesmas condições experimentais. O desenvolvimento reprodutivo foi avaliado através da idade da descida testiculare da separação prepucial,pesos dos órgãos reprodutores, concentração plasmática de testosterona, contagem de células germinativas no testículo e epidídimo, morfologia espermática, estudo do processo espermatogênico, número de células de Sertoli, do diâmetro dos túbulos seminíferos e altura de epitélio germinativo. Tambémfo~m avaliados o comportamentosexual e a fertilidadedos ratos adultos após acasalamentos naturais. A quantificação de resíduos de fenvalerato foi realizada por Cromatografia Líquida de Alta Precisão (CLAP) em amostras de órgãos e tecidos das mães, fetos e filhotes. Os resultados da quantificação de fenvalerato revelaram que o piretróide foi transferido das mães para os fetos, pela placenta, e para os filhotes, pelo leito matemo, respectivamente. O piretróide permaneceu no organismo dos filhotes até, pelo menos, 40 dias de idade, com destaque para o testículo e epidídimo. A exposição in utero e lactacional ao fenvalerato foi tóxica para o testículo, conforme mostrado pela diminuição dos pesos deste órgão nos grupos tratados e pela redução da produção espermática na puberdade, sem que tenha havido depleção androgênica ou diminuição da população de células de Sertoli. Os estudos morfológicos e morfométricos não mostraram danos sobre o aspecto histológico do testículo e o processo espermatogênico, sugerindo a ação do fenvalerato sobre a formação dos cordões seminíferos nos testículos fetais. Na idade adulta houve aumento significativo do peso da vesícula seminal e do número de ejaculações, embora os resultados dos testes de fertilidade tenham sido semelhantes entre os grupos controle e tratado. Esses achados podem ter sido uma conseqüência tardia de um desequilíbrio neuroendócrino durante o período crítico de diferenciação do sistema reprodutor masculino, quando ocorreu a exposição ao fenvalerato. Concluiu-se que o fenvalerato, diluído em óleo de milho, na dose de 40 mg/Kg, administrado para ratas do 12°. dia de prenhez até o final da lactação, foi transferido pela placenta e pelo leite matemo, provocando efeitos tardios no desenvolvimento reprodutivo da prole masculina / Abstract: Fenvalerate is a synthetic pyrethroid insecticide used in agriculture, cattle raising and in the control of domestic insects, and its reproductive effects are little-known.Some studies already have proposed that fenvalerate is an endocrine disruptor, acting as an environmentalestrogen. Studies done with rats exposed to some pyrethroids showed reduction of sperm number and plasmatic testosterone concentration. Knowingthat the male reproductive system of rats is more sensitive to the effects of toxic substances during fetal and neonatal phases, the objective of this work was to evaluate the possible Iate effects on the reproductive development at pre-puberty (aged 40 days), puberty (aged 60 days) and sexual maturity(aged 90 days) in male rats whose mothers were exposed to fenvalerate during gestation and lactation. Additionally,sexual behavior, fertilityof adult rats, transference of fenvalerate from the mothers to the offspringand its persistence in the organism of the male descendents were investigated. For this study pregnant rats (n=8) were treated with technical fenvalerate (96% purity), in the dose of 40 mglKg, from gestational day 12 until the end of lactation (critical period for differentiation of the male reproductive system of the offspring). Control rats (n=8) received com oil (vehicle), irí the same experimental conditions. The reproductive development was evaluated through of the age when testicular descent and preputial separation occurred, weight of reproductive organs, plasmatictestosterone levels, numbers of germ cells in the testis and epididymis and sperm morphology. The spermatogenic process, the number of Sertoli cells, seminiferous tubule diameter and height of the germinative epithelium were also evaluated. The sexual behavior and fertilityof adult rats were also evaluated by natural matings. Fenvalerate -residues were quantified using High Performance Liquid Chromatography (HPLC)in samples of organs and tissues of mothers,fetuses and pups. The results of the fenvalerate quantification revealed that the pyrethroid was transferred from the mothersto the fetuses through the placenta, and to the pups by maternal milk, respectively. The pyrethroid remained in the organism of the pups until at least 40 days of age, especially in the testis and epididymis. In utero and lactational exposure to fenvalerate was toxic for the testis, as shown by the diminished weight of this organ in the treated groups and reduction of the sperm production at puberty, without androgen depletion or decrease of the Sertoli cell population. The morphological and morphometrical studies did not show injuries in the histological aspect of the testis or the spermatogenic process, suggesting the action of fenvalerate on the formation of seminiferous cords in the fetal testicJe. At adult age there was a significant increase of the seminal vesicJe weight and in the number of ejaculations, although the fertilitytest results were similarbetween control and treated groups. These effects can be a Iate consequence of a neuroendocrinedysregulationduringthe critical period of differentiation of the male reproductive system, when the exposure to fenvalerate occurred. It was concluded that fenvalerate, diluted in com oil at the dose of 40 mg/Kg, administered to rats from the gestational day 12 until the end of lactation was transferred through the placenta and milk, provoking Iate effects in the reproductive development of the male offspring / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural
24

Estrogenic Activity of the Polybrominated Diphenyl Ether Flame Retardant Mixture DE-71

Mercado-Feliciano, Minerva 05 March 2008 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Polybrominated diphenyl ethers (PBDEs) are widely used flame retardants suspected to act as endocrine disruptors. We tested the commercial PBDE mixture DE-71 and its in vivo metabolites for estrogenic activity. MCF-7 breast cancer cells culture, ERE-luciferase gene expression, 3H-β-estradiol displacement from recombinant ERα, and ovariectomized (OVX) mice served as bioassays. Although DE-71 did not bind ERα, it was able to increase MCF-7 cell proliferation and this was prevented by the antiestrogen fulvestrant. DE-71 co-treatment reduced the effect of estradiol in MCF-7 cells. In the OVX mouse (BALB/c) 3-day assay, DE-71 administered alone had no effect on uterine or vaginal tissues but when administered subcutaneously potentiated estradiol’s effect on uterine weight in a dose-dependent manner. DE-71 administered SQ to BALB/c mice for 34 days slightly increased uterine epithelial height (UEH), vaginal epithelial thickness (VET) and mammary ductal lumen area, and attenuated the estradiol-induced increase in UEH; these effects were not seen in C57BL/6 mice. DE-71 increased liver weight in BALB/c, C57BL/6 and estrogen receptor-alpha knockout (ERαKO) mice. Liver cytochrome P450 1A (CYP1A) and CYP2B activities increased 2.5-fold and 7-fold respectively when DE-71 was administered PO, but only CYP2B increased (5-fold) after SQ treatment. Six OH-PBDE metabolites were found in mice after 34-day DE-71 treatment and all were able to bind recombinant ERα. Para-hydroxylated metabolites displayed a 10- to 30-fold higher affinity for ERα compared to ortho-hydroxylated PBDEs. Para-OH-PBDEs induced ERE-luciferase and produced an additive effect when coadministered with β-estradiol. DE-71 was also additive with β-estradiol. At high concentrations (≥ 5x10-5 M), ortho-OH-PBDEs were antiestrogenic in the ERE-luciferase assay. In conclusion, DE-71 behaves as a weak estrogen in both MCF-7 breast cancer cells and ovariectomized adult mice. Mice strain, treatment route and duration determined if DE-71 was estrogenic. BALB/c mice are more susceptible to DE-71 effects in estrogen target tissues than C57BL/6 mice. DE-71 increased liver weight, 5%-51% depending on mouse strain and treatment regime, independently of ERα. The observations that the DE-71 mixture does not displace 3H-β-estradiol from ERα while the hydroxylated metabolites do, suggest that the cellular and tissue effects were due to a metabolic activation of individual congeners.
25

EXPOSURE TO CIGARETTE SMOKE AND ITS IMPACT ON THE OVARIAN FOLLICLE POPULATION: MECHANISMS OF FOLLICLE LOSS

Gannon, Anne M. 04 1900 (has links)
<p>Cigarette smoking is a lifestyle behaviour associated with adverse reproductive health effects including premature exhaustion of the follicle population and premature menopause; however, the mechanisms mediating its effects on follicle loss are largely unexplored. Therefore, this thesis was undertaken to examine the effect of cigarette smoke (CS), at concentrations representative of human exposure, on follicle loss in mouse ovaries and determine the underlying mechanisms mediating their loss. CS contains over 4,000 chemicals, many of which result in reactive oxygen species (ROS) generation, which can cause cell death. In the first study, we hypothesized that follicles exposed to CS would be lost via apoptosis in a selective stage-dependent manner. Although apoptosis is a cell death pathway through which follicles are thought to die, the studies herein found no changes in apoptosis, despite increased follicle loss. Given these findings, we hypothesized that an alternative cell death mechanism was responsible. At the time, the relevance of autophagy, a novel ovarian cell death pathway, to granulosa cell death and toxicant-induced changes in ovarian function were unknown. We further demonstrated increased oxidative stress, decreased antioxidant expression, and autophagy in treated ovaries. Finally, we tested the hypothesis that CS exposure results in dysregulation of mitochondrial repair mechanisms, leading to follicle loss via autophagy-mediated granulosa cell death. We demonstrated that CS exposure activates autophagy and alters mitochondrial dynamics. Taken together, these studies provide evidence that CS causes significant follicle loss, decreases the cell’s ability to cope with ROS disrupting mitochondrial repair mechanisms, leading to autophagy-mediated follicle loss.</p> / Doctor of Philosophy (PhD)
26

Avaliação de desreguladores endócrinos em machos: estudo dos efeitos tóxicos da Ipomoea carnea em caprinos / Evaluation of endocrine disruptors in males: study of toxic effects of Ipomoea carnea in goats

Gotardo, André Tadeu 09 September 2013 (has links)
Recentemente, pesquisas vêm claramente demonstrando que xenobióticos podem apresentar efeitos deletérios sobre o sistema endócrino e passam a ser de grande importância toxicológica à medida que se tornam contaminantes ambientais. Tais substâncias passaram a ser denominadas de desreguladores endócrinos (DEs). Entre os diferentes DEs identificados, muitos são praguicidas, amplamente utilizados no meio agropecuário em todo o mundo. Atualmente, já são bem estabelecidas as metodologias para avaliação do potencial efeito DE de diferentes substâncias em roedores; porém uma busca na literatura deixa clara a falta de estudos e de protocolos para avaliação de DEs em animais de produção ruminantes, os quais certamente estão expostos a um grande número de agentes tóxicos com estas características. Assim, foi objetivo desta pesquisa dar início ao desenvolvimento de um protocolo para avaliação de efeitos DEs de xenobióticos em ruminantes. Para tal, estudou-se o bisfenol A (BPA), o qual é, classicamente, um DE para roedores. Além disto, avaliou-se o potencial efeito DE da I. carnea, uma planta tóxica de grande importância para ruminantes no Brasil e em outros países. O estudo foi realizado em duas etapas, na primeira avaliou-se os efeitos do BPA e da planta nos caprinos machos púberes; na segunda etapa propôs-se avaliar os efeitos tóxicos da exposição in utero de caprinos machos púberes a estas mesmas substâncias. Os resultados obtidos mostraram que os bodes púberes expostos ao BPA apresentaram redução significante dos níveis séricos de tiroxina, e da qualidade espermática. Também observou-se nestes mesmos animais degeneração vacuolar na rete testis. Já os caprinos machos púberes que receberam a I. carnea apresentaram aumento significante do numero de espermatozoides com alterações morfológicas e degeneração vacuolar testicular. Ainda, estes mesmos animais apresentaram diminuição estatisticamente significante dos níveis séricos dos hormônios tireoidianos (T3 e T4). O protocolo empregado para avaliação dos efeitos da exposição in utero a I. carnea ou ao BPA em machos púberes, não evidenciou nenhuma alteração hormonal e/ou reprodutiva. Conclui-se que o protocolo empregado para avaliação de possíveis efeitos DEs de xenobióticos, em ruminantes foi eficaz, no entanto, futuras metodologias deverão ser introduzidas neste protocolo, para detectar alterações mais sutis no sistema endócrino. / Recently, many studies clearly showed that xenobiotics may have deleterious effects on the endocrine system. These substances are termed endocrine disruptors (EDs), and have great toxicological significance when they become environmental contaminants. Many of EDs are identified as pesticides, which were widely used in agriculture and livestock worldwide. Currently, there are already well-established methodologies for assessing the potential effect of endocrine disruptor (ED) of different substances in rodents; however, a literature search shows clearly the lack of studies and protocols for assessing EDs in ruminant livestock, which are indubitably exposed to a large number of these substances. Thus, the objective of the present research was to start developing a protocol for evaluation of possible effects of EDs in ruminants. For this, it was studied bisphenol A (BPA), a classic ED and also I. carnea, an important toxic plant to ruminants in Brazil and other countries. The study was conducted in two stages, in the first, it was evaluated the effects of BPA and I. carnea in pubescent male goats, and in the second stage it was studied the effects in pubescent male goats from mothers exposed, during pregnancy, to BPA or the toxic plant. The pubescent male goats treated with BPA showed significant reduction in serum thyroxine levels and in the sperm quality. Those animals also presented vacuolar degeneration in the rete testis. Pubescent male goats exposed to I. carnea showed many alterations: significant increase in morphological changes in the sperm, decrease in serum levels of thyroid hormones (T3 and T4) and testicular vacuolar degeneration. The used protocol for evaluation of the effects of in utero exposure to BPA or I. carnea in pubescent male goats showed no hormonal or reproductive changes in male goats evaluated at the puberty. In conclusion, the protocol used in the present study showed to be worthy to evaluate EDs effects in ruminants; however future methodologies should be introduced to detect more subtle changes in the endocrine system.
27

Avaliação de desreguladores endócrinos em machos: estudo dos efeitos tóxicos da Ipomoea carnea em caprinos / Evaluation of endocrine disruptors in males: study of toxic effects of Ipomoea carnea in goats

André Tadeu Gotardo 09 September 2013 (has links)
Recentemente, pesquisas vêm claramente demonstrando que xenobióticos podem apresentar efeitos deletérios sobre o sistema endócrino e passam a ser de grande importância toxicológica à medida que se tornam contaminantes ambientais. Tais substâncias passaram a ser denominadas de desreguladores endócrinos (DEs). Entre os diferentes DEs identificados, muitos são praguicidas, amplamente utilizados no meio agropecuário em todo o mundo. Atualmente, já são bem estabelecidas as metodologias para avaliação do potencial efeito DE de diferentes substâncias em roedores; porém uma busca na literatura deixa clara a falta de estudos e de protocolos para avaliação de DEs em animais de produção ruminantes, os quais certamente estão expostos a um grande número de agentes tóxicos com estas características. Assim, foi objetivo desta pesquisa dar início ao desenvolvimento de um protocolo para avaliação de efeitos DEs de xenobióticos em ruminantes. Para tal, estudou-se o bisfenol A (BPA), o qual é, classicamente, um DE para roedores. Além disto, avaliou-se o potencial efeito DE da I. carnea, uma planta tóxica de grande importância para ruminantes no Brasil e em outros países. O estudo foi realizado em duas etapas, na primeira avaliou-se os efeitos do BPA e da planta nos caprinos machos púberes; na segunda etapa propôs-se avaliar os efeitos tóxicos da exposição in utero de caprinos machos púberes a estas mesmas substâncias. Os resultados obtidos mostraram que os bodes púberes expostos ao BPA apresentaram redução significante dos níveis séricos de tiroxina, e da qualidade espermática. Também observou-se nestes mesmos animais degeneração vacuolar na rete testis. Já os caprinos machos púberes que receberam a I. carnea apresentaram aumento significante do numero de espermatozoides com alterações morfológicas e degeneração vacuolar testicular. Ainda, estes mesmos animais apresentaram diminuição estatisticamente significante dos níveis séricos dos hormônios tireoidianos (T3 e T4). O protocolo empregado para avaliação dos efeitos da exposição in utero a I. carnea ou ao BPA em machos púberes, não evidenciou nenhuma alteração hormonal e/ou reprodutiva. Conclui-se que o protocolo empregado para avaliação de possíveis efeitos DEs de xenobióticos, em ruminantes foi eficaz, no entanto, futuras metodologias deverão ser introduzidas neste protocolo, para detectar alterações mais sutis no sistema endócrino. / Recently, many studies clearly showed that xenobiotics may have deleterious effects on the endocrine system. These substances are termed endocrine disruptors (EDs), and have great toxicological significance when they become environmental contaminants. Many of EDs are identified as pesticides, which were widely used in agriculture and livestock worldwide. Currently, there are already well-established methodologies for assessing the potential effect of endocrine disruptor (ED) of different substances in rodents; however, a literature search shows clearly the lack of studies and protocols for assessing EDs in ruminant livestock, which are indubitably exposed to a large number of these substances. Thus, the objective of the present research was to start developing a protocol for evaluation of possible effects of EDs in ruminants. For this, it was studied bisphenol A (BPA), a classic ED and also I. carnea, an important toxic plant to ruminants in Brazil and other countries. The study was conducted in two stages, in the first, it was evaluated the effects of BPA and I. carnea in pubescent male goats, and in the second stage it was studied the effects in pubescent male goats from mothers exposed, during pregnancy, to BPA or the toxic plant. The pubescent male goats treated with BPA showed significant reduction in serum thyroxine levels and in the sperm quality. Those animals also presented vacuolar degeneration in the rete testis. Pubescent male goats exposed to I. carnea showed many alterations: significant increase in morphological changes in the sperm, decrease in serum levels of thyroid hormones (T3 and T4) and testicular vacuolar degeneration. The used protocol for evaluation of the effects of in utero exposure to BPA or I. carnea in pubescent male goats showed no hormonal or reproductive changes in male goats evaluated at the puberty. In conclusion, the protocol used in the present study showed to be worthy to evaluate EDs effects in ruminants; however future methodologies should be introduced to detect more subtle changes in the endocrine system.
28

Estudo da toxicidade reprodutiva do óleo essencial de orégano (Origanum vulgare L.) em ratos Wistar

Hollenbach, Clarissa Boemler January 2013 (has links)
No presente trabalho avaliaram-se os efeitos do óleo essencial do orégano (Origanum vulgare L.) sobre a fertilidade, desenvolvimento ponderal de ratos Wistar, potencial teratogênico, bem como o desenvolvimento físico, motor e comportamental das progênies. A dosagem inicial do óleo essencial foi obtida através de ensaio in vitro frente a linhagens de isolados de Candida spp. O óleo foi extraído pelo processo arraste de vapor e analisado por cromatografia GC/MS. Constituíram-se cinco grupos experimentais com 10 machos e 30 fêmeas cada, um grupo controle negativo (GC-) que recebeu o veículo da emulsão do óleo de orégano (água destilada + Tween 80 0, 001%) um grupo controle positivo (GC+) que recebeu os compostos majoritários do óleo, timol 3% e terpine-4-ol 3%, e três grupos tratados com a emulsão contendo óleo essencial do orégano contendo 3% V / V (GO1), 9% V/ V (GO2) e 27% V / V (GO3). Os animais foram tratados diariamente por via oral usando sonda oro-gástrica flexível, com mesmo volume (10 mg / mL). Os machos foram tratados durante 91 dias, sendo 70 dias antes do acasalamento e 21 dias de acasalamento, após este período, os machos foram eutanasiados para coleta de órgãos para análise histopatológica, coleta de sangue e processamento dos órgãos sexuais para contagens espermáticas. As fêmeas foram tratadas antes (14 dias) e durante o acasalamento, gestação (21 dias) e lactação (21 dias). Metade das fêmeas prenhes sofreu cesariana no 21º dia de gestação, e os fetos foram usados para a avaliação de teratogenia. O restante das fêmeas pariu a termo, tiveram o comportamento maternal avaliado e as suas proles foram avaliadas a partir do nascimento, quanto às características de desenvolvimento e testes reflexos. Na puberdade, aos 65 dias, um filhote de cada sexo por ninhada foi eutanasiado para avaliação histopatológica e contagens espermáticas e aos 75 dias de idade um macho de cada ninhada teve seu comportamento testado em campo aberto. Na idade adulta a prole formou casais não consaguineos para a realização do comportamento sexual. Os resultados mostram que a administração do óleo essencial nas diferentes doses não interferiu no desenvolvimento ponderal de machos e fêmeas tratados nem das suas progênies (ANOVA p > 0,05). Nos machos, o óleo essencial de orégano interferiu diminuindo o número de células espermáticas, o número total de espermatozóides armazenados na cauda do epidídimo e os níveis de testosterona plasmática, na morfologia espermática o óleo aumentou o percentual de malformações espermáticas nos grupos tratados, de forma dose dependentes, igualmente no controle positivo. Nas fêmeas a taxa de acasalamento apresentou diferença estatisticamente significativa em relação ao grupo controle negativo nas duas doses mais altas de óleo essencial (9% e 27%). Na dose mais alta houve perdas pós-implantação, diferentes estatisticamente do GC-. Na avaliação esquelética dos fetos, houve diferença estatisticamente significativa no percentual geral de fetos com anomalias esqueléticas, em relação ao controle negativo, em 3%, 9% e GC+. Com relação às progênies, não houve alterações estatísticamente significativas nos grupos, no que se refere ao desenvolvimento ponderal, nos testes reflexos, nas contagens espermáticas e dosagem de testosterona plasmática realizadas na puberdade, no teste de campo aberto e no teste de comportamento sexual. Com base nos resultados obtidos, é possível concluir que a dose inicial (3%), considerada terapêutica, é segura para a reprodução de ratos Wistar, no entanto quando esta dose é aumentada para 9% e 27%, alterações nas variáveis reprodutivas dos machos podem acontecer. / In the present study were evaluated the effects of the essential oil of oregano (Origanum vulgare L.) on fertility and weight development of rats on the teratogenic potential as well as the physical, motor and behavioral of the progenies. The initial dose was obtained by in vitro against strains of Candida isolates spp. The oil was extracted by the process of steam drag chromatography and analyzed by GC / MS. Constituted five experimental groups with 10 males and 30 females each, a negative control group (GC-) who received vehicle emulsion emulsion of oil of oregano (distilled water + Tween 80 0, 001%) a positive control group (CG + ) receiving the major compounds from the oil, thymol 3% and terpine-4-ol 3% and three groups treated with the emulsion containing essential oil of oregano containing 3% V / V (GO1 ), 9% V / V (GO2) and 27% V / V (GO3). The animals were treated daily orally using orogastric tube flexible, with the same volume (10 mg / ml). Males were treated for 91 days with 70 days prior to mating and during mating 21 days, after this period, males were euthanized to collect organs for histopathology, blood collection and processing of sexual organs for sperm counts. Females were treated before (14 days) and during mating, gestation (21 days) and lactation (21 days). Half of pregnant females underwent cesarean section on day 21 of gestation, and the fetuses were used for the evaluation of teratogenicity. The rest of the females gave birth at term, had evaluated whether maternal behavior and their offspring were evaluated from birth, for the development traits and reflex tests. At puberty, 65 days, a pup of each sex per litter was euthanized for histopathological assessment and sperm counts at 75 days of age a male from each litter had tested their behavior in the open field. In adulthood the offspring formed consaguineos couples not to perform sexual behavior. The results showed that administration of essential oil at different doses did not affect the weight development of males and females treated or their progeny (ANOVA p> 0.05). In males, the essential oil of oregano interfered decreasing the number of sperm cells, total number of sperm stored in the cauda epididymis and plasma testosterone levels on sperm morphology oil increasing the percentage of sperm abnormalities in the treated groups in a dose dependent manner, equally positive control. In females mating rate was statistically significantly different compared to negative control group in the two higher doses of essential oil (GO2 and GO3). At the higher dose (GO3) losses occurred before and after deployment, the GC-statistically different. In assessing skeletal fetuses of females who underwent cesarean section, there was a statistically significant difference in the overall percentage of fetuses with skeletal anomalies, relative to the negative control in GO1, GO2 and GC +. Regarding progenies, no significant statistics changes in groups, with regard to weight development, testing reflexes, sperm counts and measurement of plasma testosterone at puberty, in open field test, in the test of sexual behavior Based on these results, we conclude that the initial dose (3%), considered therapy is safe for reproduction of rats, however when this dose is increased to 9% and 27%, changes in the male reproductive variables can occur.
29

Effects of some Endocrine Disruptors on Human and Grey Seal Uterine Cells

Bredhult, Carolina January 2007 (has links)
<p>The effects of environmental contaminants in humans and animals are of great concern. Some contaminants are endocrine disruptors that may interfere with the endogenous hormonal signalling and disturb, for example, reproductive organs and functions.</p><p>Primary uterine myometrial cells originating from women and Baltic grey seals were exposed to some polychlorinated biphenyls (PCBs) and their metabolites. Even though human and Baltic grey seal myometrial cells responded differently to the tested PCBs, the results indicate that PCBs can influence myometrial cell proliferation <i>in vitro</i>.</p><p>The prevalence of uterine leiomyomas was investigated among 257 Baltic grey seals. Leiomyomas were only present in females older than 22 years, at a prevalence of 65%. Proliferation in leiomyoma cells was detected in individuals lacking ovarian proliferation support, suggesting the presence of an exogenous stimulant. By taking into account temporal alterations in the contaminant burden of the seals, PCB exposure was found to be associated with leiomyoma prevalence. In conclusion, PCB exposure may be related to uterine leiomyoma development and proliferation in Baltic grey seals <i>in vivo</i>.</p><p>Human endometrial endothelial cells (HEECs) were exposed to some endocrine disruptors, and the effects of the endocrine disruptors on cell proliferation and viability were studied. All evaluated endocrine disruptors decreased HEEC proliferation and most also decreased HEEC viability. Further studies revealed that the reduction in HEEC proliferation after exposure to o,p’-DDT was associated with differential expression of mRNA involved in proliferation, defence response, and lipid and cholesterol metabolism compared to untreated HEEC. </p><p>In conclusion, these studies suggest that endocrine disruptors affect cultured cells from the female reproductive tract of humans and grey seals, and may have deleterious effects on proliferation, viability, and genes involved in defence response, and lipid or cholesterol metabolism.</p>
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Effects of some Endocrine Disruptors on Human and Grey Seal Uterine Cells

Bredhult, Carolina January 2007 (has links)
The effects of environmental contaminants in humans and animals are of great concern. Some contaminants are endocrine disruptors that may interfere with the endogenous hormonal signalling and disturb, for example, reproductive organs and functions. Primary uterine myometrial cells originating from women and Baltic grey seals were exposed to some polychlorinated biphenyls (PCBs) and their metabolites. Even though human and Baltic grey seal myometrial cells responded differently to the tested PCBs, the results indicate that PCBs can influence myometrial cell proliferation in vitro. The prevalence of uterine leiomyomas was investigated among 257 Baltic grey seals. Leiomyomas were only present in females older than 22 years, at a prevalence of 65%. Proliferation in leiomyoma cells was detected in individuals lacking ovarian proliferation support, suggesting the presence of an exogenous stimulant. By taking into account temporal alterations in the contaminant burden of the seals, PCB exposure was found to be associated with leiomyoma prevalence. In conclusion, PCB exposure may be related to uterine leiomyoma development and proliferation in Baltic grey seals in vivo. Human endometrial endothelial cells (HEECs) were exposed to some endocrine disruptors, and the effects of the endocrine disruptors on cell proliferation and viability were studied. All evaluated endocrine disruptors decreased HEEC proliferation and most also decreased HEEC viability. Further studies revealed that the reduction in HEEC proliferation after exposure to o,p’-DDT was associated with differential expression of mRNA involved in proliferation, defence response, and lipid and cholesterol metabolism compared to untreated HEEC. In conclusion, these studies suggest that endocrine disruptors affect cultured cells from the female reproductive tract of humans and grey seals, and may have deleterious effects on proliferation, viability, and genes involved in defence response, and lipid or cholesterol metabolism.

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