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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.
61

Desenvolvimento do sistema reprodutivo de Echinostoma paraensei (Trematoda: Digenea) de hamsters (Mesocricetus auratus) experimentalmente infectados, analisado por microscopia de luz de campo e microscopia laser confocal / Development of the reproductive system of Echinostoma paraensei (Trematoda: Digenea) from hamsters (Mesocricetus auratus) experimentally, analised by light and confocal scanning laser microscopy

Joyce Gonçalves Rozário de Souza 16 September 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O conhecimento da morfologia e ultraestrutura dos helmintos permite a correta classificação destes organismos, bem como fornece subsídios que poderão ser utilizados para diagnóstico e controle. A microscopia laser confocal é uma ferramenta para estudar a organização estrutural de várias espécies de helmintos, possibilitando acesso a detalhes morfológicos não evidenciados pela microscopia óptica. Echinostoma paraensei é um trematódeo, digenético, hermafrodita parasito de numerosos hospedeiros vertebrados. Neste trabalho foi investigado o desenvolvimento dos órgãos reprodutivo e a morfometria de E. paraensei, desde a fase jovem até a adulta, como contribuição ao conhecimento do desenvolvimento reprodutivo desta espécie. Os trematódeos foram recuperados aos 3, 4, 5, 6, 7, 10, 14 e 21 dias posterior à infecção (dpi) experimental em hamsters. Estes foram corados em carmim clorídrico, desidratados em série alcoólica e montados em lâmina permanente em bálsamo do Canadá, fotografados e medidos usando microscopia de luz de campo claro (MCC) e microscopia de varredura laser confocal (MVLC). Entre 3 e 4 dpi, os primórdios genitais estavam presentes e nenhuma organização do sistema reprodutivo foi visualizada por MCC e MVLC. Os primórdio do ovário, dos testículos e da bolsa do cirro foram visualizados por MCC aos 5 e 6 dpi, no entanto, MVLC dos helmintos aos 5dpi mostra que estes primórdios, o ootipo e o útero estavam presentes, como estruturas individualizadas. A bolsa do cirro apresenta metratermo e o ovário com primórdio do oótipo adjacente aos 7dpi por MVLC. A vesícula seminal, receptáculo seminal, células diferenciadas nos testículos, ducto e reservatório vitelínico e oviducto foram visualizados após 10 dias, enquanto os espermatozóides na vesícula seminal, ovos e oócitos, células vitelínicas, poro e canal de Laurer aos 14 dias. A morfometria evidencia um acelerado crescimento dos órgãos reprodutores a partir do 7 dia. Os testículos apresentam aumento significativo no comprimento do 7 ao 21 dia e o ovário durante o período de 7 à 10 dpi. Aos 21 dpi, todos os helmintos apresentaram glândulas vitelínicas, útero contendo ovos e espermatozóides no oviducto enquanto outros ovos estão sendo formados. As mudanças morfológicas acentuadas durante a gametogênese consistem no aumento do comprimento do helminto, maturação das gônadas, desenvolvimento e maturação das glândulas vitelínicas. O desenvolvimento do helminto como um todo está relacionado à maturação dos órgãos reprodutivo masculino e feminino indicando o investimento deste trematódeo em garantir a produção e eliminação dos ovos ao meio exterior. / The knowledge about morphology and ultra structure of helminthes are great importance in correct classification these organisms. The Scanning Laser Microscopy (LSM) is an important tool to study the structural organization of several helminthes species. Echinostoma paraensei is a trematode, digenetic, hermaphroditic parasite of several hosts. In this study, the development of reproductive organs and the morphometry of E. paraensei from young stage to adult worm were investigated, to contribute knowledge of the reproductive development of this specie. The trematodes were recovered on 3, 4, 5, 6, 7, 10, 14 and 21 days post infection (dpi) from experimental hamsters. It were dehydrated in alcohol series, stained with hydrochloric carmine, mounted on permanent slide using Canada balsam, photographed and measured using light microscopy (LM) and Scanning Laser Microscopy (LSM). Between 3 and 4 dpi the genital anlage were present and were not observed reproductive system organization by either LM and LSM. The anlage of ovary, testes and Cirruss sac were seen at 5 and 6dpi by LM, however LSM from 5dpi image shows theses anlage, ootype and uterus are present as individualized structure. Cirrus sac showed metraterm and ootype adjacent to primordial ovary were seen at 7 dpi by LSM. The seminal vesicle, seminal receptacle, differentiated cells in the testes, viteline ducts and oviduct were visualized after 10 days infection, while sperms in seminal vesicle, eggs, oocyte, Laurer canal and pore from 14 dpi by LSM. The morphometry shows a rapid growth of reproductive organs from 7th day. The testes have significantly increased length from 7 until 21dpi and ovary from 7 until 10dpi. All helminthes showed vitellines glands, uterus contained eggs and sperm in oviduct while another eggs were forming at 21 dpi. The marked morphologic changes during gametogenesis are increase of body length of helminthes, gonad maturation and development and maturation of vitelline glands. The development of helminthes as a whole is related to maturation of female and male organs of reproductive system showing the investment this trematode taken to ensuring the production, maintenance and delivery the eggs to external environment.
62

Estudo dos efeitos dos elementos traços presentes nas partículas provenientes da queima do diesel no sistema reprodutivo de Danio rerio (zebrafisch): análise morfológica e histológica / Effects of trace elements present in diesel exhaust particulates in the reproductive system of Danio rerio (zebrafish): Morphological and histological analysis

Fabiana Moura Novaes Mendez 11 December 2012 (has links)
A qualidade do ar nas áreas urbanas tende a apresentar concentrações indesejáveis de contaminantes provenientes da queima de biomassa, não havendo um sistema abrangente de monitoramento. Achados in vivo mostram que o diesel pode conter compostos que modulam a atividade do estrógeno. Estudos in vitro apoiam essa ideia, como o estudo realizado com cloreto de metileno extraído do diesel que comprova atuar como ativadores de ligação para os receptores de estrógeno. Esse trabalho tem por objetivo avaliar o efeito da exposição à metais presentes nas partículas de exaustao de diesel (PED) na morfologia do ovaário através da histologia, e análise do padrão de expressão dos receptores de estrógeno (ERs) no ovário de zebrafish (Danio rerio) usando a metodologia de PCR em tempo real. Fêmeas adultas de zebrafish foram expostas à concentrações ambientais de combinado de metais (Ni = 0,181 mg/L ; Fe = 0,07455 mg/L ; Pb= 0,05 mg/ L; Cd = 0,029 mg/ L; Cr = 0,161 mg/L ; Cu = 0,017 mg / L) por 3 dias. Em relação a contagem de ovócitos atrésicos a média observada nos animais expostos foi de 1,5 ± 0,4 e nos controles foi de 1,34 ± 0,3. Contudo, não houve diferença significativa entre os grupos (p > 0,05). Na expressão dos três genes receptores de estrógeno (esr1, esr2a, esr2b) as médias foram: 0,68; 1,32; 0,54; respectivamente. No entanto, não houve alteração significativa na expressão desses genes em relação aos controles. Os elementos traços presentes nas PED em concentração ambiental e em exposição aguda na fase adulta não alteram a expressão dos ERs o também não afetam o número de folículos atrésicos nos ovários / The air quality in urban areas tends to have undesirable concentrations of contaminants from biomass combustion, without a monitoring system. In vivo findings show that diesel may contain compounds that modulate the activity of estrogen. In vitro studies support this idea, as the study with methylene chloride extract from diesel proves that this substance act as activators binding to the estrogen receptors (ERs). This study aims to evaluate the effect of exposure to metals present in diesel exhaust particles (PED) in ovary morphology through histology, and analysis of expression pattern of ERs in ovary of zebrafish (Danio rerio) using real time PCR metodology. Adult females were exposed to ambient concentrations of combined metals (Ni = 0.181 mg / L, Fe = 0.07455 mg / L Pb = 0,05 mg / L; Cd = 0.029 mg / L; = 0.161 mg Cr / L, Cu = 0.017 mg / L) for 3 days. The mean of atretic oocytes counting observed in animals exposed was 1.5 ± 0.4 and the controls was 1.34 ± 0.3. However, no significant difference between groups was observed (p> 0.05). The expression of the three genes estrogen receptor (esr1, esr2a, esr2b) mean were: 0.68, 1.32, 0.54, respectively. However, no significant change in the expression of these genes in relation to controls was observed. In conclusion, the trace elements present in the PED concentration in environmental and acute exposure in adulthood not alter the expression of ERs and does not affect the number of atretic follicles in the ovary
63

Identificação e localização das procineticinas e seus receptores no ovário de ratas com síndrome dos ovários policísticos induzida por esteroides sexuais / Identification and localization of prokineticins and their receptors in ovary of polycystic ovary syndrome rat models induced by sex steroids

Giulia Silva Araujo 14 March 2017 (has links)
A síndrome dos ovários policísticos (SOP) é um distúrbio endócrino caracterizado por anovulação crônica e hiperandrogenismo. Modelos animais em ratas são usados para estudar processos complexos da SOP. As procineticinas (PROKs) são proteínas relacionadas a apoptose, proliferação vascular e regulação do sistema reprodutor. No entanto, seu padrão de expressão e função não são bem conhecidos no ovário com SOP. Este estudo propõe-se a identificar e localizar as PROKs e seus receptores nos ovários de ratas com SOP experimental. Foram utilizadas 33 ratas Wistar divididas em 3 grupos que receberam, entre o 1º e o 3º dia de vida, uma única injeção por via subcutânea de: propionato de testosterona (1,25 mg/0,1 mL, GT, n=12); benzoato de estradiol (0,5 mg/0,1 mL, GE, n=11) e óleo de oliva (0,1 mL, GC, n=10). Aos 90-95 dias de idade, os animais foram eutanaziados e os ovários removidos para avaliação da expressão gênica e proteica das procineticinas 1 e 2 e seus receptores por qRT-PCR e imunoistoquímica. A expressão dos genes Prok1 e Prok2 nos ovários de ratas do GT foi maior quando comparado ao GC (p=0,0157 e p=0,0354). Houve maior expressão da proteína PROK2 em células da teca interna (p=0,0049) e nas células intersticiais (p=0,0068) de folículos antrais nos ovários de ratas do GT em relação ao GC. PROK2 foi mais expressa em células da granulosa dos folículos pré-antrais comparado aos folículos antrais no GT (p=0,0098). Concluímos que as procineticinas estão expressas no ovário do modelo estudado em diferentes padrões, e que a PROK2 parece exibir maior expressão no grupo testosterona. Por apresentar papéis relevantes no controle do eixo hipotálamo-hipófise-gonadal, acreditamos que esses resultados podem abrir uma linha de investigação sobre o papel dessa proteína na fisiopatologia da síndrome / Polycystic ovary syndrome (PCOS) is an endocrine disorder characterized by chronic anovulation and hyperandrogenism. Animal models have been used to study PCOS pathophysiology. Prokineticins (PROKs) are proteins with functions related to apoptosis, vascular proliferation and reproductive physiology. However, their expression patterns and functions are unknown in the PCOS ovary. The aim of this study is to identify and localize the PROKs and their receptors in PCOS rat models induced by testosterone or estradiol. Thirty-three female Wistar rats aged between 1-3 days were sorted into three groups according to the compounds injected subcutaneously: Testosterone propionate (1.25 mg / 0.1 mL, TG, n = 12); Estradiol benzoate (0.5 mg / 0.1 mL, EG, n = 11) and olive oil (0.1 mL, CG, n = 10). At 90-95 days of age, the animals were euthanized and the ovaries removed for evaluation of prokineticins 1 and 2 and their receptors by qRT-PCR and immunohistochemistry. The expression of the genes Prok1 and Prok2 in the ovaries was higher in TG compared to CG (p=0.0157 and p=0.0345). There was higher expression of PROK2 in theca interna (p=0.0049) and interstitial cells (p=0.0068) of antral follicles in the ovaries of TG vs CG; PROK2 was higher expressed in the granulosa cells of the preantral follicles compared to the antral follicles in the TG (p=0.0098). We conclude that prokineticins are expressed in the ovary of the animal model studied and they present different patterns, PROK2 seems to exhibit higher expression in the testosterone group. Due important roles in the control of the hypothalamicpituitary- gonadal axis, we believe that these results may open a line of investigation about the role of this protein in the pathophysiology of the syndrome
64

História de vida e variabilidade morfológica e molecular de Leptinaria unilamellata (d’Orbigny, 1835) (Mollusca, Pulmonata, Subulinidae)

Carvalho, Camila de Medeiros de 17 February 2009 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-11T11:12:29Z No. of bitstreams: 1 camillademedeirosdecarvalho.pdf: 2802334 bytes, checksum: 24c8eb756878e03e092c98273834a1a8 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-10-11T15:56:30Z (GMT) No. of bitstreams: 1 camillademedeirosdecarvalho.pdf: 2802334 bytes, checksum: 24c8eb756878e03e092c98273834a1a8 (MD5) / Made available in DSpace on 2016-10-11T15:56:30Z (GMT). No. of bitstreams: 1 camillademedeirosdecarvalho.pdf: 2802334 bytes, checksum: 24c8eb756878e03e092c98273834a1a8 (MD5) Previous issue date: 2009-02-17 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / No presente estudo, foram elucidados aspectos da história de vida e morfologia do gastrópode terrestre Leptinaria unilamellata (d’Orbigny, 1835), além disso, foi verificada a ocorrência de variabilidade nos padrões conquiliomorfológicos e conquiliomorfométricos, assim como na morfologia do sistema reprodutor de moluscos provenientes de diferentes populações. A estratégia de história de vida da espécie foi caracterizada. Foram determinados os padrões de crescimento, reprodução e longevidade e elucidada a estratégia relacionada ao desenvolvimento dos embriões. Com base nos resultados obtidos, L. unilamellata foi classificada como espécie K-estrategista, ovovivípara, cujo padrão de história de vida é determinado pela alocação diferencial de energia para diferentes funções biológicas, nas diferentes fases do ciclo de vida. O sistema reprodutor foi caracterizado anatomicamente e histologicamente. Os resultados forneceram informações até então inexistentes, a cerca da morfologia microscópica do sistema reprodutor dessa espécie, corroborando aspectos comportamentais, como o hermafroditismo simultâneo e a ovoviviparidade. Foram observados o padrão geral da morfologia da concha de L. unilamellata e sua variação entre os espécimes das localidades de Juiz de Fora, MG; Cruzília, MG; Barra Mansa, RJ, e Floriano, distrito do município de Barra Mansa, RJ. O padrão de crescimento da concha foi descrito através do estudo da alometria do crescimento de moluscos de diferentes idades. As relações entre os padrões morfométricos dos diferentes morfotipos demonstraram a presença de dois grupos similares, um composto pelos morfotipos de Barra Mansa e Floriano, e outro pelos morfotipos de Juiz de Fora e Cruzília. O estudo permitiu o conhecimento sobre o padrão de formação da concha ao longo do desenvolvimento, bem como as relações entre as diferentes medidas lineares aferidas. Foi investigada a variabilidade morfológica do sistema reprodutor de espécimes de L. unilamellata das localidades de Juiz de Fora, MG; Cruzília, MG; Belo Horizonte, MG; Barra Mansa, RJ e Floriano, distrito do município de Barra Mansa, RJ. Os moluscos provenientes das diferentes populações estudadas apresentam diferenças na morfologia do sistema reprodutor, podendo assim ser reconhecidos como morfotipos distintos. Entretanto, tais morfotipos não puderam ser distinguidos pelo perfil molecular gerado através da técnica de PCR-RFLP. Os resultados do estudo da morfologia e análises morfométricas confirmaram a maior semelhança entre os morfotipos de Barra Mansa e Floriano, e entre os morfotipos de Juiz de Fora e Cruzília. A morfologia e morfometria dos moluscos de Belo Horizonte mostraram-se mais relacionadas àquelas dos dois últimos 9   morfotipos. As variações foram verificadas principalmente nos órgãos da região proximal do sistema reprodutor, os quais, provavelmente por estarem envolvidos no sucesso do acasalamento, sofrem maiores pressões seletivas. O presente estudo representa uma contribuição para o melhor entendimento da biologia reprodutiva de L. unilamellata. O estudo da conquiliomorfometria foi uma ferramenta útil para o conhecimento do padrão de crescimento dos moluscos e para a detecção de variabilidade morfológica interpopulacional. O conhecimento da morfologia do sistema reprodutor permitiu compreender aspectos da história de vida e distinguir morfotipos provenientes de diferentes populações. A combinação das diferentes abordagens utilizadas constitui um modelo que pode ser empregado para o melhor conhecimento da biologia de diferentes espécies de invertebrados. / In this study, were elucidated aspects of life history traits and morphology of the terrestrial gastropod Leptinaria unilamellata (d'Orbigny, 1835). In addition, was verified the occurrence of variability in patterns of shell morphology and shell morphometrics, as well as morphology of the reproductive system of snails from different populations. The life history strategy of L. unilamellata was characterized. We determined growth, reproduction, and longevity patterns of this species and the strategy related to development of embryos were determined. We might conclude from the results that L. unilamellata is a K-strategist species, ovoviviparous, whose life history patterns are determined by the differential allocation of energy for different biological functions, in different stages of life cycle. The reproductive system was characterized in terms of anatomical and histological aspects. The results provided new information about histological morphology of reproductive system of this species, corroborating behavioral aspects, such as simultaneous hermaphroditism and ovoviviparity. We were observed the general pattern of shell morphology of L. unilamellata and its variation among populations from Juiz de Fora, MG; Cruzília, MG, Barra Mansa, RJ, and Floriano, district of Barra Mansa, RJ. To describe the shell growth pattern, was accomplished the study of growth allometry with molluscs of different ages. The relationships between morphometric patterns of the morphotypes demonstrated the presence of two similar groups, one comprising the morphotypes of Barra Mansa and Floriano, and another by morphotypes of Juiz de Fora and Cruzília. The results of the present study clarified the shell growth pattern during the snails’ development, and the relationships between different shell linear variables. There was investigated the morphological variability of the reproductive system of specimens of L. unilamellata from Juiz de Fora, MG; Cruzília, MG, Belo Horizonte, MG, Barra Mansa, RJ and Floriano, RJ. As a result, were found differences in morphology of the reproductive system between molluscs from different populations, especially regarding the penial complex. So, snails from each locality could be recognized as distinct morphotypes. However, such morphotypes could not be distinguished through the molecular profile generated by PCRRFLP. The length of bursa copulatrix, width of epifalo, width of flagellum and width of oviduct were the linear measurements that differed more between snails from different localities and these, therefore, are the variables with greater strength for the distinction of morphotypes. The results of the morphological and morphometric studies, as well as the Euclidean analysis and cluster analysis, confirmed the greatest similarity between the 11   morphotypes from Barra Mansa and Floriano, and between morphotypes from Juiz de Fora and Cruzília. The morphology and morphometry of reproductive system of molluscs from Belo Horizonte were more related to those of the last two morphotypes. The patterns of similarity resulting from discriminant analysis confirmed these results. The variations were observed mainly in organs of the proximal region of reproductive system, probably because they are involved in success of mating, and consequently, more exposed to selective pressures. The present study represents a contribution to a better understanding of the reproductive biology of L. unilamellata, focusing on both biological and behavioral aspects, such as morphology of reproductive system and shell. The study of shell morphometrics has been proved to be a useful tool for understanding the pattern of growth of snails over lifetime and also for detection of morphological interpopulation variability. Similarly, knowledge of reproductive system morphology clarified aspects of life history and allowed distinguish morphotypes from different populations. The combination of the different approaches used in this study constitutes a study model that can be used for reach a better understanding about the biology of different invertebrate species.
65

Insights Into The Mechanism Of Actions Of Luteinizing Hormone And Prostaglandin F2α In The Regulation Of Corpus Luteum Function Of Monoovulatory Species

Shah, Kunal B 07 1900 (has links) (PDF)
Corpus luteum (CL), a transient endocrine structure formed from the ruptured ovarian follicle after ovulation, secretes progesterone (P4) that is essential for establishment and maintenance of pregnancy in mammals. The biosynthesis and secretion of P4 from CL depends, in general, on trophic hormones of the anterior pituitary gland and on hormones or factors originating from ovary, uterus, embryo and placenta. The structure and function of CL tissue is regulated by intricate interplay between two types of factors, namely, the luteotrophic factors, which stimulate CL growth and function, i.e., P4 secretion, and the luteolytic factors, which inhibit CL function and lead to luteal regression. In monoovulatory species such as higher primates and bovines, a striking diversity in the regulation of CL function exists not only between species, but also within the species during different stages of the luteal phase. In higher primates, unlike other species, one of the important characteristics of CL regulation is that, during non-fertile cycle, circulating LH appears to be the sole trophic factor responsible for maintenance of its function, and during fertile cycle, chorionic gonadotropin (CG), an LH analogue, originating from placenta maintains CL function. In higher primates, the role/involvement of luteolytic factors during luteolysis remains elusive. On the other hand, in the bovine species, the role/involvement of luteolytic factor, prostaglandin (PG) F2α during luteolysis is well established. It should be pointed out that in both the species, the mechanism of luteolysis is still poorly understood and the work presented in this thesis attempts to address these lacunae. Further, in bovines, studies have been carried out to examine potential trophic factor(s) responsible for the maintenance of CL function. Chapter I provides an extensive review of literature on CL structure and function with emphasis on factors that influence its growth, development, function and demise in primates and bovines. In Chapter II, employing bonnet monkey (Macaca radiata) as the representative animal model for higher primates, various studies have been conducted to examine the role of molecular modulators involved in regulation of CL function, particularly during spontaneous luteolysis. Although, it is well established that LH is essential for the maintenance of CL function in higher primates, the mechanism(s) responsible for the decline in serum P4 levels at the end of non-fertile cycles, without a concomitant change in circulating LH milieu, remains to be addressed. Several experiments have been conducted to examine the component(s) of luteotrophic (LH/CG) signaling that is/are modulated during luteolysis in the bonnet monkey CL. To understand the relative lack of responsiveness of CL to the circulating LH during the late luteal phase, LH/CG receptor (R) dynamics (expression of LH/CGR and its various transcript variants) was examined throughout the luteal phase and during different functional states of the monkey CL. The results indicated presence of LH/CGR mRNA, its transcript variants and functional LH/CGR protein in the monkey CL on day 1 of menses. Moreover, the functionality of receptors was tested by confirming the biological response of the CL to bolus administration of exogenous LH preparations, which eventually suggested factor(s) downstream of LH/CGR activation to account for the decline in CL function observed during non-fertile cycle. Studies have been conducted to identify molecular modulators that would selectively exploit intraluteal processes to regulate trophic signaling pathways that are critical to the control of luteal function. Immunoblot and qPCR analyses were carried out to examine presence and activation of Src family of kinases (SFKs) and cAMP-phosphodiesterases (PDEs) during various functional states of CL. The results revealed an increased activation of Src (phosphorylated at Tyr 416) during spontaneous and PGF2α/CET-induced luteolysis that may participate in the regulation of cAMP levels in part by increasing the cAMP-PDE activity observed during spontaneous luteolysis. This observation raised the question on the possible mechanism by which CG, an analog of pituitary LH, rescues CL function during early pregnancy. Thus, subsequent experiments involving LH/hCG administration in CET-treated animals as well as simulated early pregnancy animal model were conducted and the results revealed that, a bolus of LH/hCG decreased Src activation and cAMP-PDE activity accompanying a momentous increase in cAMP levels in both these models that further led to a concomitant increase in P4 secretion. Although the mechanisms of action of LH/CG involve modulation of a number of signaling pathways in the CL, by far, the results from various experiments suggested that it leads to activation of Src kinase and cAMP-PDE, thus causing inhibition of various elements of the primary signaling cascade- AC/cAMP/PKA/CREB during spontaneous luteolysis. One of the consequences of activation of Src kinase and cAMP-PDE was the regulation of expression of genes associated with steroidogenesis and it was observed that expression of SR-B1, a membrane receptor associated with trafficking of HDL-CE into the luteal cells, was lower in the regressed CL. The results taken together suggest that the decrease in responsiveness of CL to LH milieu during non-fertile cycles is not associated with changes in LH/CGR dynamics, but, is instead coupled to the activation of Src kinase and cAMP-PDE, inhibition of molecules downstream of LH signaling, and a decrease in the SR-B1 expression that regulates cholesterol economy of the luteal cell, and in turn, P4 secretion. The control of primate CL function appears to be dominated by the luteotrophic factors (LH/CG) over the luteolytic factors, since the process of luteal regression was overcome by administration of LH/CG. Further, in the primate CL, the molecular modulators of LH/CG signaling (Src kinase and PDE) are maintained in the repressed state by the luteotrophic factor LH/CG for maximum steroidogenic function. In contrast, in non-primate species, without invoking a role for the luteotrophic factor, essentially the synthesis and secretion of luteolytic factor, PGF2α, from the uterus is kept in check during pregnancy by the trophoblast derived IFN- and thus allowing CL to continue to function that is essential for maintenance of pregnancy. In the bovine species, the mechanism of PGF2α-induced luteolysis that involves a change in expression of genes associated with various processes of cellular function is poorly understood. Experiments were conducted utilizing buffalo cows (Bubalus bubalis) as a model system, to determine temporal changes in the global gene expression profile of the CL in response to PGF2α treatment. For this purpose, CL tissues were collected on day 11 of estrous cycle without treatment (designated as 0 h) and at 3, 6 and 18 h post PGF2α treatment for various analyses. Global changes in gene expression pattern in the CL were investigated employing Affymetrix GeneChip bovine genome array and the results are presented in Chapter III. The hybridization intensity values obtained by microarray analysis were subjected to R/Bioconductor tool. Following the application of highly stringent statistical filters to eliminate false positives, a set of differentially expressed genes were identified. The differentially expressed genes were further classified based on a fold change cut-off filter of ≥2, and the analysis revealed 127 genes to be differentially expressed within 3 h of PGF2α administration, of these 64 and 63 genes were up-regulated and down-regulated, respectively. Analysis of microarray data at 6 h post PGF2α administration revealed 774 genes to be differentially expressed, of which 544 genes were up-regulated, while 230 genes were down-regulated. The microarray analysis performed on CL tissues collected at 18 h post PGF2α administration showed that out of the total 939 differentially expressed genes, 571 genes were up-regulated, while 368 genes were down-regulated. Analysis of the ontology report for the biological processes category showed that initially in response to PGF2α administration, genes regulating steroidogenesis, cell survival and transcription were differentially regulated in the CL, but at later time points, differential expression of genes involved in apoptosis, PGF2α metabolism, tissue remodeling and angiogenesis was observed. Further, involvement of molecules downstream of LH/IGF-1 activation was investigated and the results obtained indicated that PGF2α interfered with the LH/IGF-1 signaling since the expression of LH/CGR, GHR and pAkt were down-regulated following PGF2αadministration. Furthermore, the functional luteolysis observed post PGF2αadministration appeared to be due to an interruption in cholesterol trafficking to inner mitochondrial membrane, since StAR expression was inhibited. The results obtained also demonstrated that the expression of AGTR1, VEGFR2 and R3 were down-regulated following PGF 2α administration. Further, the data obtained also suggested modulation of expression of pro- and anti-angiogenic factors upon PGF2α-treatment indicative of an involvement of other autocrine or paracrine factor(s) in the regression of bovine CL. This was an interesting finding as it suggests a novel and potential functional relationship between angiogenesis and the luteolytic response of CL to PGF2α administration. In bovines, despite extensive research being carried out to examine factors involved in the regulation of development and function of the CL, the trophic factor(s) required for maintenance of CL function, especially, P4 biosynthesis and secretion are not well characterized. It was hypothesized that the function of the CL during its finite lifespan must be responsive to LH as well as to various growth factors. Thus, experiments were conducted to examine the effects of increased LH and GH/IGF-I on the maintenance of CL function during mid luteal phase and post PGF2α administration and the results of these studies are presented in Chapter IV. To elucidate the role of LH as a trophic factor in the regulation of CL function, effects of increased endogenous LH through GnRH administration and exogenous hCG injections were examined. The results indicated an absence of noticeable effect of various hCG/GnRH treatments on circulating P4 levels. On the other hand, administration of GH resulted in increased serum IGF-1 and P4 levels. It was further observed that the administration of a combination of hCG and GH increased serum P4 levels better than treatment with GH alone. Further experiments were carried out to examine the complex reciprocal relationship between LH/GH and PGF2α on expression of genes involved in the regulation of luteal structure and function. In buffalo cows, administration of exogenous hCG and/or GH following inhibition of CL function by PGF2α administration did not prevent the PGF2α-induced decline in serum P4 levels, but PGF2-mediated decrease in expression of LH/CGR and GHR genes was prevented upon GH administration. However, the decrease in StAR expression was not restored by hCG and GH treatments, thereby indicating that PGF2 action was not prevented by hCG and/or GH treatments. Taken together, the results of studies carried out in buffalo cows employing various experimental model systems suggest essential role for LH and GH/IGF-1, however, these factors were unable to reverse PGF2α-induced luteolysis. Further, our crucial findings of the effects of increased endogenous LH and IGF-1, in addition to their relationship with luteolytic agents such as PGF2α will open new avenues for studying the mechanisms involved in the regulation of structural and functional properties of the buffalo CL. It is well known that a large number of buffalo cows experience loss of pregnancy and infertility due to inadequate luteal function and/or failure of timely insemination. Results from our studies suggest that the incorporation of PGF2α and hCG or GH/IGF-1 protocols in buffalo cows to be beneficial for improving their breeding efficiency as these protocols are likely to increase luteal function with defined luteolysis. To summarize, the results of studies described in the present thesis provide new insights into the physiological and molecular mechanisms involved in the regulation of CL function during luteolysis in the monoovulatory species. The results suggest that the maintenance of CL function appears to be dependent on both luteotrophic and luteolytic factors, but with a varied degree of dominance between the two species examined. Further, the results indicate that while the luteotrophic factors (LH/CG) dominate the CL regulation in primates, the regulation of CL function in bovines is dominated by the actions of luteolytic factor (PGF2α). In monoovulatory species, the luteotrophic and luteolytic factors following binding to their specific plasma membrane receptors on the luteal cells, would counteract each other and modulate activation of various downstream signaling molecules subsequently leading to regulation of gene expression and P4 secretion (Fig.5.1). LH: luteinizing hormone; CG: chorionic gonadotropin; LH/CGR: LH/CG receptor; Gαs: stimulatory α-subunit of trimeric G-protein; AC: adenylate cyclase; cAMP: cyclic adenosine monophosphate; PKA: protein kinase A; p: phosphorylation: CREB: cAMP response element binding protein; SR-B1: scavenger receptor class B, type I; SF-1: steroidogenic factor 1; LRH-1: liver receptor homologue 1; P4; progesterone; Src; sarcoma; PDE4D: cAMP phosphodiesterase 4D; StAR, steroidogenic acute regulatory protein; PGF2α: prostaglandin F2α; PTGFR: PGF2α receptor; PLC: phospholipase C; CYP19A1: cytochrome P450 aromatase; PTGR1: Prostaglandin reductase 1; AREG: Amphiregulin; RTK: receptor tyrosine kinase; Akt: protein kinase B; FKHR: forkhead transcription factor; DAPL1: death associated protein like 1; ARG2: Arginase, type II Growth factor LH/CGR RR AC Gαs ? Gα TT P? Gα K PKP src cAMP ? P Akt PDE4D P PFKHR FKHR CREB P LRH-1CREB P SF-1 Genes associated with Genes associated with apoptosis ? CYP19A1, apoptosis SR-B1 PTGR1 DAPL1 SF-1, LRH-1 AREG ARG 2 P4 biosynthesis Apoptosis? P4 biosynthesis Apoptosis MONKEY BUFFALO COW Shown here is the diagram depicting intracellular signaling pathways regulated by luteotrophic factor (LH) and luteolytic factor (PGF2α) and their cross talk to counteract changes in the expressions of genes associated with the biosynthesis and secretion of P4 and apoptosis in the CL. In primates, LH/CG activates a multitude of intracellular signaling cascades, primarily Gαs/AC/cAMP/PKA/CREB leading to changes in gene expression. LH during early and mid luteal phase and CG during pregnancy maintain the activation of Src and PDE in an inhibitory state. However, during the late luteal phase of non-fertile cycle, results in present study suggests that activated Src levels and PDE activity increase, with accompanying decrease in cAMP and pCREB levels leading to concomitant decrease in SR-B1 expression, and in turn, P4 secretion. Surprisingly, regulation of apoptotic gene expression and CL regression are still unclear. In bovines, PGF2α of uterine origin mediates changes in luteal gene expression and results in decreased P4 secretion, principally by reduction in StAR level. The present study suggests that during luteolysis PGF2α affects the genes regulated by LH, by interfering with LH (and perhaps IGF-1) signaling leading to alteration in the expression of genes crucial for CL structure and function. (Pl refer the abstract file for figures)
66

The Histological Effects of Injections of Fish Pituitary Extracts on the Testes of Male Frogs, (Rana Pipiens), and the Reproductive System of Immature Mice

Robertson, William George 08 1900 (has links)
The purpose of this investigation was first, to make a histological and cytological study of the testis of male frogs, Rana pipiens, and to determine if there were tissue or cellular changes as well as physiological effects caused by fish pituitary-extract injections. Second, to determine if injections of fish pituitary extract into immature female white mice caused histological changes in the ovaries and uteri.
67

Analyse de la fertilité des vaches laitières Holstein «Repeat Breeder»

Bonneville-Hébert, Ariane 12 1900 (has links)
L’importance de la problématique des vaches laitières non gestantes avec multiples inséminations (› 3) communément appelées « Repeat Breeder » (RB), au Québec, repose sur deux facteurs: son incidence et son impact économique. Actuellement, l’incidence du syndrome RB au Québec est de ± 25% (Rapport annuel, juin 2008, www.dsahr.ca). Les pertes monétaires associées à ce problème proviennent des frais vétérinaires et d’insémination, de la diminution de productivité ainsi que des pertes en lien avec la réforme involontaire. Afin d’avoir de meilleures connaissances sur ce syndrome, nous devons connaître les facteurs de risques généraux impliqués et ensuite explorer la condition individuelle de ces vaches problèmes. Dans la première partie de ce mémoire, une banque de données informatisées répertoriant 418 383 lactations fut analysée. L’objectif de ce projet de recherche était d’évaluer l’impact des problèmes reproducteurs post-partum et l’effet du nombre de lactations comme facteurs de risques de la vache Repeat Breeder. L’analyse a permis d’établir la dystocie comme étant la condition ayant le plus de conséquences sur la fertilité future. D’autres facteurs de risques à savoir le nombre de lactations influencent le pronostic reproducteur. La deuxième partie de ce mémoire consistait à explorer, à l’aide d’outils cliniques, la condition individuelle des vaches RB. Une étude cohorte fut menée sur des vaches Holstein en fin de période d’attente volontaire au jour 7 du cycle oestral. Les tests cliniques étudiés furent la vaginoscopie, l’examen transrectal, l’ultrasonographie du système reproducteur, la présence d’estérases leucocytaires, la bactériologie et la biochimie du liquide utérin, la cytologie endométriale et le profil de progestérone sérique. Les résultats de ces tests cliniques dévoilent que l’examen bactériologique du liquide utérin est révélateur du statut reproducteur futur. / Two factors underlie the Repeat Breeder (RB) concerns in Quebec: its incidence and economic impact. Currently RB incidence in Quebec is of ± 25% (yearly Report, June 2008, www.dsahr.ca). Monetary losses related to the RB are the result of veterinary expenses and insemination, loss of productivity and the involuntary culling. In order to have a better knowledge of this syndrome, one must understand the general risk factors involved and then explore the individual condition of these problem cows. The goal of the first part of the project was to assess the impact of the postpartum reproductive problems and the effect of the lactation number as risk factors of the Repeat Breeder cow. A computerized data bank listing 418 383 lactations was analyzed. The analysis established dystocia as being the condition with the most consequences on future fertility. Other risk factors namely the number of lactations influence the reproductive prognosis as well. The second part of the research was to explore the individual condition of the RB using clinical tools. A cohort study was conducted on Holstein cows at the end of the voluntary waiting period on day 7 of the oestrous cycle. The clinical tests studied were vaginoscopy, trans-rectal examination, ultrasonography of the reproductive system, presence of leukocyte esterase, bacteriology and biochemistry of uterine fluid, endometrial cytology and serum progesterone profile. The results of these clinical tests reveal that the bacteriological analysis of uterine fluid is indicative of future reproductive status.
68

Factors associated with cervical cancer among women of reproductive age group in Swaziland

Hlophe, Thabo Trevor 07 1900 (has links)
The study is informed by inadequate information on factors associated with the prevalence, incidence and mortality of cervical cancer cytological abnormalities in Swaziland. The aim of the study was to explore and describe factors associated with cervical cancer among women of reproductive age between 15 and 49 years in Swaziland. Quantitative descriptive design with a data extraction tool was used to retrospectively generate observational data from 1748 patients’ records in Mbabane Government Hospital from January 2014 through to December 2014. Bivariate logistic regression was used to establish relationship between cervical cancer and each explanatory variable. The overall prevalence of cervical cytology test results was 24.9%. The combination of marital status, HIV status, ART status, age at sexual debut have been identified as factors associated with cervical abnormalities. Most importantly, the results will also serve as evidence for the development of a national cervical cancer screening policy and also strengthening the cancer registry in Swaziland. / Health Studies / M.A. (Public Health)
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Efeito do consumo de hidrolisado de clara de ovo sobre as alterações neurológicas, reprodutivas e cardiovasculares promovidas pela exposição crônica ao cloreto de mercúrio (HgCl2) em ratos

Rizzetti, Danize Aparecida January 2016 (has links)
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70

O efeito do anestro induzido por restrição alimentar sobre a morfologia de útero e ovários e a expressão do RNAm do precursor do hormônio concentrador de melanina. / The effect of food restriction-induced anestrus on the morphology of uterus and ovaries and the melanin-concentrating hormone precursor mRNA expression.

Silva, Jéssica Beteto da 14 November 2017 (has links)
Estudos hodológicos sugerem um dimorfismo sexual das projeções da área incerto-hipotalâmica (IHy), com áreas relevantes para o controle reprodutivo mais densamente inervadas em fêmeas. Estudos funcionais mostraram que o RNAm do precursor do hormônio concentrador de melanina (ppMCH) varia apenas na IHy, durante o ciclo estral e é reduzido em ratas em anestro induzido por restrição alimentar (RA). Nosso objetivo foi analisar em camundongos fêmeas, as alterações na morfologia de útero e ovários e na expressão do RNAm do ppMCH da IHy ocasionadas pelo anestro induzido por RA. Para isso, camundongos fêmeas C57BL/6 foram distribuídas em controle (C), restrito (R; ração = 70% do C) e realimentado (RR). Os animais R foram perfundidos após 4, 8 e 12 dias para coleta de encéfalo, útero e ovários. Houve um aumento no número de folículos antrais nos animais R12 comparados ao R4 e redução da área uterina nos animais R8 com recuperação dos RR. Não foi possível detectar alterações na expressão do RNAm do ppMCH na IHy. / Hodological studies suggest a sexual dimorphism of the incerto-hypothalamic area (IHy) projections since relevant areas to the reproductive control are more densely innervated in females. Functional studies have shown that the MCH precursor mRNA (ppMCH) varies only in the IHy during the estrous cycle of an intact rat and is decreased in anestrus rats induced by food restriction. We aim to analyze, in female mice, the changes in uterine and ovarian morphology and expression of IHy ppMCH mRNA in anestrus induced by food restriction. For this, C57BL/6 female mice were distributed in control (C), food restricted (FR) and refed (RR). FR were perfused after 4, 8 and 12 days to collect the brain, uterus and ovaries. Our results show an increased number of antral follicles of R12 compared to R4 and a reduction in the uterine area of R8 with restoration in RR. It was not possible to detect changes in ppMCH mRNA expression in IHy.

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