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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.
261

Endogenous Retroviral RNA Expression in Humans

Hu, Lijuan January 2007 (has links)
Human endogenous retroviruses (HERVs) constitute about 8% of the human genome. There are around 4000 pol-containing retroviral integrations in the human genome, which makes it impractical to measure each of them separately. Therefore we developed a set of degenerate real time PCRs to detect major groups bearing sequence similarities to gammaretroviruses, one of the largest groups of human endogenous retrovirus, and betaretroviruses, some of which have integrated into the human genome most recently and which remain the most intact. It was found that, although both gammaretroviral and betaretroviral RNAs were broadly expressed in various healthy tissues including reproductive tissues and brain, a differential expression pattern was observed. My work further revealed that HERVE and HERVW, two gammaretroviral sequences, were ubiquitously and highly expressed in pathologic and normal female reproductive tissues with tissue specific patterns. Expression of HERVE was higher in endometriotic tissue than in normal endometrium. HERVE and HERVW RNAs were higher in normal ovarian tissue than in ovarian cancer. Besides these tissue- and neoplasia-related differences, there were wide differences in HERV expression among individuals. Next, a selective pattern of HERVW upregulation was demonstrated in SK-N-DZ, a neuroblastoma cell line, upon re-oxygenation after a period of hypoxia or with 5-azacytidine, a demethylating agent. Furthermore, broad and high expressions of gammaretrovirus-like transcripts in different brain areas analyzed were identified. The expression levels were variable among different donors. In conclusion a ubiquitous HERV expression was observed in tissues and cell lines, with various patterns. At this stage the data are not sufficient to conclude whether HERV has any physiological or pathological roles in humans. However, their differential expression patterns are compatible with functional roles of HERV in humans.
262

Role of Stromal Cell-Derived Factor-1 in Neoangiogenesis in Endometriosis Lesions

VIRANI, SOPHIA 22 December 2011 (has links)
Endometriosis affects 5-10% of women and is characterized by the growth of endometrial tissue outside of the uterus. Treatment for endometriosis primarily focuses on symptom relief, is short term with severe side effects and often leads to recurrence of the condition. Establishing new blood supply is a fundamental requirement for endometriosis lesions growth. This has led to the idea that antiangiogenic therapy may be a successful approach for inhibiting endometriosis. Recent evidence indicates that endothelial progenitor cells (EPCs) contribute to neoangiogenesis of endometriotic lesions. These EPCs are recruited to the lesion site by stromal cell-derived factor-1 (SDF-1). We hypothesize that SDF-1 is central to the neoangiogenesis and survival of endometriotic lesions and that administration of SDF-1 blocking antibody will inhibit lesion growth by inhibiting angiogenesis in a murine model of endometriosis. Immunohistochemistry for SDF-1 and CD34 was performed on human endometriosis and normal endometrial samples. Quantification of SDF-1 and EPCs was performed in the blood of endometriosis patients and controls using ELISA and flow cytometry, respectively. A new mouse model of endometriosis was developed using BALB/c-Rag2-/-/IL2rg-/- mice to investigate role of SDF-1 in neoangiogenesis. Either SDF-1 blocking antibody or an isotype control was administered on a weekly basis for four weeks. Weekly samples of peripheral blood from mice were analyzed for SDF-1, other cytokines of interest and EPCs. Mice were euthanized at seven weeks to observe lesion growth and blood vessel development. Our results indicate overabundance of SDF-1 and CD34+ progenitor cells in human endometriotic lesions compared to eutopic endometrium. In the mouse model, SDF-1 and circulating EPC levels decreased from pre-treatment levels after one week, and remained constant over the course of the treatment in both SDF-1 blocking antibody and isotype control groups. In the SDF-1 blocking group, reduced vascularity of lesions, identified by immunofluorescence staining for CD31, was revealed compared to isotype controls. These findings suggest that SDF-1 may be responsible for CD34+ progenitor cell recruitment to the neoangiogenic sites in endometriosis. Blocking of SDF-1 reduces neovascularization of human endometriotic lesions in a mouse model. Further studies on blocking SDF-1 in combination with other antiangiogenic agents are needed. / Thesis (Master, Anatomy & Cell Biology) -- Queen's University, 2011-12-21 19:34:43.054
263

Cellular Transport of Prostaglandins in the Ovine Uterus

Lee, Je Hoon 03 October 2013 (has links)
In ruminants, prostaglandin F2 alpha (PGF2α) is released from the endometrium in a pulsatile pattern at the time of luteolysis. The luteolytic PGF2α pulses are transported from the uterus to the corpus luteum (CL) through the utero-ovarian plexus (UOP) to cause luteolysis. At the time of establishment of pregnancy, interferon tau (IFNT) secreted by the conceptus suppresses the pulsatile release of PGF2α and thereby rescues the CL and maintains its secretion of progesterone. However, basal concentrations of PGF2α are higher in pregnant ewes than in cyclic ewes. The pulsatile release of PGF2α likely requires selective carrier-mediated transport and cannot be supported by a simple diffusion mechanism. The molecular and functional aspects of carrier mediated transport of PGF2α from the uterus to the ovary through the utero- ovarian plexus (UOP) at the time of luteolysis and recognition/establishment of pregnancy are largely unknown ruminants. Results indicate that intrauterine inhibition of (PGT) prevents the pulsatile release of PGF2α independently of spatial expressions of estrogen receptor (ESR-1) and oxytocin receptor (OXTR) proteins by the endometrium at the time of luteolysis in sheep. PGT protein is expressed in the UOP during the estrous cycle and pharmacological inhibition of PGT prevents transport of luteolytic PGF2α pulse through the UOP in sheep. IFNT activates novel JAK-SRC-EGFR-RAS-RAF-ERK1/2-EGR-1 signaling modules in endometrial luminal epithelial (LE) cells and regulates PGT- mediated release of PGF2α through these novel cell-signaling pathways. IFNT stimulates ERK1/2 pathways in endometrial LE cells and inhibition of ERK1/2 inhibits IFNT action and restores spatial expression of OXTR and ESR-1 proteins in endometrial LE cells and restores endometrial luteolytic pulses of PGF2α in sheep. Collectively, the results of the present study provide the first evidence to indicate that transport of endometrial luteolytic PGF2α pulses from the uterus to the ovary through the UOP is controlled by a PGT-mediated mechanism in sheep, new mechanistic insight into molecular mechanisms regulating cellular and compartmental transport of PGF2α at the time of luteolysis, and new mechanistic understanding of IFNT action and release of PGF2α from the endometrial LE cells and thus opens a new arena of research in IFNT signaling and PGT function.
264

Qualidade de vida e eventos adversos após a radioterapia em mulheres com câncer ginecológico = um estudo de coorte prospectivo / Quality of life and adverse events after radiotherapy in gynecologic cancer survivors : a cohort study

Vaz, Ana Francisca 18 August 2018 (has links)
Orientador: Aarão Mendes Pinto-Neto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-18T03:36:10Z (GMT). No. of bitstreams: 1 Vaz_AnaFrancisca_D.pdf: 1602661 bytes, checksum: 0dbc9ea54c85593a5a17af092c3b8961 (MD5) Previous issue date: 2011 / Resumo: Objetivos: Investigar a frequência de eventos adversos antes e após a radioterapia, a proporção de mulheres sexualmente ativas, avaliar a qualidade de vida (QV) e identificar seus preditores em uma coorte de mulheres com câncer ginecológico. Métodos: Estudo de coorte prospectivo com 107 mulheres com câncer ginecológico (colo do útero ou endométrio), idade (21 a 75) anos, tratadas com radioterapia, 89 (teleterapia e braquiterapia) 10 (braquiterapia) 8 (teleterapia) no Hospital da Mulher Prof. Dr. José Aristodemo Pinotti CAISM/UNICAMP. A QV foi avaliada através do questionário da Organização Mundial da Saúde - (WHOQOL-breve), antes da radioterapia (T0), 4 meses (T1), 1ano (T2) e 3 anos (T3) após o tratamento. Os eventos adversos após a radioterapia foram graduados de acordo com a escala Common Terminology Criteria Adverse Event (CTCAE) v 3.0. Os escores de QV foram avaliados através do teste de Wilcoxon pareado e os seus preditores identificados por meio de regressão linear. Utilizou-se o teste de McNemar para avaliar as diferenças entre as frequências de sintomas sexuais e da menopausa, e da proporção de mulheres sexualmente ativas após a radioterapia em relação à avaliação inicial. Resultados: A mediana da idade das participantes antes da radioterapia foi 60 anos. O domínio meio ambiente e a saúde geral eram os mais comprometidos antes da radioterapia. Dor (49,5%) e sangramento vaginal (36,9%) foram as queixas mais frequentes. Anemia (p<0,01) e náusea e/ou vômito (p=0,01) interferiram negativamente no domínio físico; dor no domínio físico (p<0,01), QV global (p=0,02) e saúde geral (p=0,01), e história de cirurgia positivamente na saúde geral (p<0,01). Três anos após a radioterapia observou-se uma redução da frequência de secura vaginal (26,7% em T0 vs 8,3% em T3; p<0,005), aumento da proporção de mulheres sexualmente ativas (21,5% em T0 vs 44,2% em T3; p=0,005) em relação à avaliação inicial, e aumento significativo dos escores de QV para o domínio psicológico, saúde geral e QV global. Dor associou-se negativamente com os domínios físico, psicológico e relacionamento social (p<0,05); dispareunia com os domínios físico e relacionamento social (p<0,05); diminuição do interesse sexual com o domínio psicológico (p<0,01) e maior renda positivamente com o domínio psicológico e saúde geral (p<0,05). Conclusão: O domínio meio ambiente e a questão relacionada à saúde eram os mais prejudicados antes da radioterapia. Os sintomas do câncer foram os fatores de maior interferência na QV. Três anos após a radioterapia verificou-se melhora da QV e aumento significativo do número de mulheres sexualmente ativas em relação à avaliação prévia. A presença de dor, dispareunia e diminuição do interesse sexual interferiram negativamente na QV / Abstract: Objectives: To investigate the frequency of adverse events before and after radiotherapy, the proportion of sexually active women, evaluate quality of life (QOL) and identify their predictors in a cohort of women with gynecologic cancer. Methods: A prospective cohort study of 107 women with gynecologic cancer (cervical or endometrial), aged (21 to 75) years, treated with radiotherapy, 89 (teletherapy and brachytherapy) 10 (brachytherapy) 8 (teletherapy) in the Prof. Dr. José Aristodemo Pinotti Women?s Hospital-CAISM/UNICAMP. QOL was assessed by the World Health Organization- (WHOQOL-BREF) questionnaire, before radiotherapy (T0), 4 months (T1),1year (T2) and 3 years (T3) after treatment. The adverse events following radiotherapy were scored according to the Common Terminology Criteria Adverse Event (CTCAE) scale, v 3.0. QOL scores were assessed by the paired Wilcoxon test and their predictors were identified by linear regression analysis. The McNemar test was used to assess the differences between the frequencies of sexual symptoms and menopause, as well as the proportion of sexually active women after radiotherapy compared to baseline evaluation. Results: The median age of the participants before radiotherapy was 60 years. The environmental domain and general health were the most impaired before radiotherapy. Pain (49.5%) and vaginal bleeding (36.9%) were the most frequent complaints encountered. Anemia (p<0.01), nausea and/or vomiting (p=0.01) negatively interfered with the physical domain. Pain negatively interfered with the physical domain (p<0.01), global QOL (p=0.02) and general health (p=0.01). A history of surgery positively interfered with general health (p<0.01). Three years after radiotherapy, there was a decrease in the frequency of vaginal dryness (26.7% in T0 vs 8.3% in T3; p<0.005), an increase in the proportion of sexually active women (21.5% in T0 vs 44.2% in T3; p=0.005) in comparison to baseline assessment, and a significant increase in QOL scores for the psychological domain, general health and global QOL. Pain was negatively associated with the physical, psychological and social relationship domains (p<0.05). Dyspareunia was negatively associated with the physical and social relationship domains (p<0.05). Decreased sexual interest was negatively associated with the psychological domain (p<0.01). A higher income was positively associated with the psychological domain and general health (p<0.05). Conclusion: The environmental domain and the question related to general health were the most compromised before radiotherapy. Cancer symptoms were the factors that most interfered with QOL. Three years after radiotherapy, there was an improvement in QOL and a significant increase in the number of sexually active women compared to prior evaluation. Pain, dyspareunia and decreased sexual interest negatively interfered with QOL / Doutorado / Fisiopatologia Ginecológica / Doutor em Ciências da Saúde
265

Avaliação comparativa do potencial miogênico de células tronco mesenquimais adultas obtidas de diferentes fontes / Comparative analysis of the myogenic potencial of adult mesenchymal stem cells derived from different tissues

Marcos Costa Valadares 10 January 2014 (has links)
As Distrofias Musculares Progressivas (DMPs) constituem um grupo de doenças genéticas caracterizadas por uma degeneração progressiva e irreversível da musculatura esquelética. Dentre as diferentes abordagens terapêuticas propostas para esse grupo de doenças, a terapia celular com células-tronco mesenquimais (CTMs) tem sido um foco importante de pesquisas. Muitos tipos de CTMs já foram descritas com o intuito de reconhecer qual o tipo ideal a ser usado em uma possível terapia celular para DMPs. Neste trabalho comparamos o potencial terapêutico de células-tronco de diferentes fontes obtidas de um mesmo doador. Escolhemos as células de pericito (CP) como ferramenta de estudo, uma vez que elas estão presentes em todos os tecidos irrigados por vasculatura. Isolamos pericitos de 4 tecidos da mesma doadora (endométrio, trompa, tecido adiposo e músculo). Em seguida, injetamos 1 milhão dessas células intraperitonialmente em camundongos Utrntm1KedDmdmdx/J (duplo knockout para o gene da distrofina e utrofina) semanalmente, por 8 semanas, e avaliamos a clínica e a sobrevida desses animais. Observamos que nas condições experimentais desse estudo, o potencial miogênico dessas células é insuficiente para ser utilizado como terapia regenerativa. Entretanto, apesar dos testes padronizados não detectarem nenhuma melhora clínica aparente, os animais tratado com pericitos de gordura mostraram uma curva de sobrevivência significativamente maior do que os controles não tratados. Como não houve diferenciação miogênica, esses resultados sugerem que os efeitos benéficos ocorreram através de liberação de fatores tróficos e imunoreguladores (efeito parácrino). É digno de nota que apesar das células serem todas derivadas de pericito e de uma mesma doadora o aumento de sobrevida só foi observado com células do tecido adiposo. Esses resultados indicam que o potencial terapêutico de CP difere de acordo com sua origem e que essa diferença não depende do genoma do doador. Esses resultados constituem um passo inicial, porém, valioso na compreensão do potencial de utilização dessas células em terapias / Progressive Muscular Disorders (PMDs) are a group of heterogeneous genetic diseases characterized by an irreversible degeneration of the muscle tissue due to mutation or absence of a protein. Among the many different available therapeutic approaches to treat PMDs, cell therapy using mesenchymal stem cells (MSCs) are one of the most studied ones. There are many types of MCSs described to date and the need to identify the best one suited to treat PMDs has yet to be addressed. In this thesis, we compared the therapeutic potential of different types of stem cells derived from the same donor. First, we chose pericytes as a tool of comparison, as this cell is unequivocally present in all vascularized tissues. We isolated pericytes of 4 different tissues from the same donor (endometrium, fallopian tubes, adipose tissue and muscle). We injected 1 million of these cells intraperitonially in Utrntm1KedDmdmdx/J mice (knockout for the dystrophin and utrophin gene) weekly for 8 weeks evaluating the clinical features and survival curve of these mice. We observed that, in the experimental conditions of this study, the myogenic potential of these cells is insufficient to be harnessed as therapy for regenerative purposes. However, despite the fact that the standardized tests did not detect any apparent clinical improvement, mice treated with pericytes derived from adipose tissue had a survival curve greater than control treated mice. As we could not observe any myogenic differentiation or cell engraftment, this results suggests that the beneficial effect observed could be due to the releasing of trophic and immune modulator factors (paracrine effect). It is noteworthy that despite all cells being derived from the same donor, the increase in life expectancy was only observed in pericytes derived from the adipose tissue. These results indicate that the therapeutic potential of pericytes differs according to their tissue of origin and the difference is not due to genetic differences. This is still preliminary data but it is valuable in understanding the therapeutic potential of these cells
266

Análise da Expressão Gênica Diferencial em Endometriose / Differential Gene Expression Analysis in Endometriosis.

Juliana Meola 01 April 2008 (has links)
A endometriose é uma doença ginecológica benigna, de etiologia complexa e multifatorial, caracterizada pela presença de estroma e tecido glandular tipo endométrio fora da cavidade uterina. Afeta de 10 a 15% da população feminina, que apresentam sintomatologia variada, incluindo dor pélvica e infertilidade. Para elucidar mecanismos potenciais que estejam envolvidos com a fisiopatologia complexa desta doença, analisamos o perfil de expressão gênico diferencial pela metodologia de hibridação subtrativa em tecido eutópico e ectópico (lesões peritoniais e endometrioma ovariano) de 17 mulheres com endometriose, no início da fase proliferativa do ciclo menstrual. Foram identificados 291 genes desregulados nas lesões endometrióticas, considerados como genes candidatos. Para a validação dos dados, utilizamos a metodologia de PCR em tempo real para os genes CTGF e SPARC, indicados como superexpressos; e MYC, MMP3, IGFBP1 e PAEP como menos expressos nas lesões. Diferenças significativas de expressão nas lesões peritoniais foram obtidas para os genes SPARC, MYC, IGFBP1, PAEP e nos endometriomas ovarianos para os genes MMP3 e PAEP. Sugerimos que a desregulação dos genes SPARC, MYC, MMP3, IGFBPI e PAEP seja responsável pela perda da homeostase celular nas lesões endometrióticas, contribuindo para a implantação e sobrevivência do tecido ectópico no ambiente extra-uterino. Este trabalho disponibilizou ao banco de dados da literatura, 291 genes com expressão gênica diferencial em lesões endometriótricas peritoniais e ovarianas como candidatos a investigações futuras. / Endometriosis is a benign gynecological disease, which presents a multifactorial and complex etiology, characterized by the presence of stromal and glandular endometrium tissue outside the uterine cavity. Ten to 15% of the female population is affected by the disease with a wideranging symptomatology including pelvic pain and infertility. To clarify the potential mechanisms involved in the complex physiopathology of this disease, we analyzed the differential gene expression profile by subtractive hybridization in eutopic and ectopic tissue (peritoneal lesions and ovarian endometriomas) from 17 women with endometriosis, in the early proliferative phase of the menstrual cycle. We identified 291 genes deregulated in the endometriotic lesions, considered as candidate genes. For data validation, Real Time PCR was applied for genes CTGF and SPARC, indicated as overexpressed; and for genes MYC, MMP3, IGFBP1 and PAEP, indicated as downregulated in the lesions. Significant differences in the peritoneal lesions expression were obtained for genes SPARC, MYC, IGFBP1, PAEP and in the ovarian endometriomas for genes MMP3 and PAEP. We suggest that the deregulation of genes SPARC, MYC, MMP3, IGFBPI and PAEP is responsible for loss of cellular homeostasis in the endometriotic lesions, contributing for the implantation and maintenance of the ectopic tissue in the extra-uterine environment. This study provided 291 genes with differential gene expression, in peritoneal and ovarian lesions, to the literature database as candidates for future investigations.
267

Estudo comparativo das alterações morfológicas e vasculares do útero durante a prenhez precoce de embriões de clones bovinos produzidos por SCNT em três diferentes apresentações gestacionais / Comparative study of morphological and vascular changes of the uterus during the early pregnancy of bovine embryos clones produced by SCNT in three different gestational phenotypes

Marcelo de Luna Freire Oliveira 19 July 2017 (has links)
A clonagem por transferência de núcleo de células somáticas (SCNT) em bovinos é uma biotécnica ineficiente, porém é uma ferramenta muito importante para pesquisas em biologia do desenvolvimento. Estudos prévios em nosso laboratório identificaram três fenótipos gestacionais de clones bovinos produzidos por SCNT: (1) gestação normal (CNG) - presença do embrião (EP), vesícula embrionária (VE) e corpo lúteo ativo (CL); (2) gestação anembrionada (CAG) - presença da VE e CL ativo e ausência de EP; (3) receptoras com CL ativo persistente sem a presença de EP e VE (CPCL). Vacas doadoras de embriões foram sincronizadas pelo protocolo de super-ovulação (SOV) e inseminadas artificialmente, os embriões obtidos após sete dias da ovulação foram transferidos para receptoras que ao ficarem gestantes formaram o grupo controle (GC). O objetivou do estudo foi investigar as características morfovasculares do útero nestes quatro fenótipos gestacionais. A hipótese central foi que as características morfovasculares do útero são moduladas diferentemente nos três fenótipos gestacionais de embriões clonados por SCNT e gestação controle. Vacas Nelores foram sincronizadas e utilizadas como receptoras de embriões. Coletas de sangue para análise de progesterona e exames ultrassonográficos nos modos B e Doppler para análise da morfologia e vascularização uterina foram realizados a cada dois dias a partir do dia 6 até o dia 30 pós-ovulação. Entre os dias 31 e 36, as receptoras foram abatidas e o útero coletado para análises in situ. A simetria entre cornos, o grau de desenvolvimento de carúnculas e da VE foram mensurados e amostras endometriais coletadas para quantificação relativa do fator de crescimento endotelial vascular (VEGF) e seu receptor do tipo 2 (VEGF-R2) por western-blotting. No total foram realizadas 212 sincronizações do ciclo estral, das quais 79 receptoras receberam embriões de clones por SCNT e 49 receberam embriões produzidos in vivo. Aos 25 dias pós-ovulação as taxas de concepção por grupo foram: CNG = 15,1% (12/79), CAG = 2,5% (2/79), CPCL = 8,8% (7/79) e CG = 24,4% (10/49). Duas receptoras da raça Tabapuã (Bos taurus indicus) do fenótipo do grupo CAG provindas de outro experimento foram incluídas nas análises. Algumas receptoras foram excluídas do experimento devido a perdas gestacionais ocorridas antes do momento do abate, restando para as análises sete receptoras no grupo CNG, três no CAG, quatro no CPCL e nove no CG. Somente o grupo CG apresentou diferença de perfusão vascular entre os cornos uterinos ipso e contralateral (P&LT;0,05). Em relação ao corno ipsolateral, os grupos CG e CNG apresentaram maior perfusão vascular em relação ao grupo CPCL do dia 24 ao 30 (P&LT;0,05). Porém, com a média dos escores da perfusão vascular endometrial de ambos os cornos, o grupo CNG apresentou maiores valores em relação aos grupos CAG e CPCL nos dias 24 e 30. Os índices de resistência vascular (RI) nas artérias uterinas confirmaram os dados subjetivos de diferença de perfusão vascular entre cornos, o corno ipsolateral do grupo CG apresentou menor RI em relação ao contralateral nos dias 22, 24, 28 e 30 (P&LT;0,05) e os grupos CNG e CPCL não apresentaram diferença entre cornos (P&GT;0,05). Entre os grupos, o RI no CG e CAG foi menor que no CPCL no dia 30 (P&LT;0,05). A concentração de progesterona (P4) sanguínea foi menor no grupo CPCL em relação aos grupos CG e CNG nos dias 18 e 26 (P&LT;0,05). A P4 atingiu valores próximos de 8 ng/ml a partir do dia 22 nos grupos CG e CNG, sendo que no grupo CPCL os valores foram inferiores à 6 ng/ml a partir do dia 14. As análises in situ revelaram maior frequência de assimetria de cornos uterinos no grupo CG em relação aos grupos CNG, CAG e CPCL; o grupo CNG obteve maior frequência de ocorrência de carúnculas e VE desenvolvidas nos dois cornos uterinos em relação aos grupos CAG e CPCL (P&LT;0,05), não diferindo do grupo CG (P&GT;0,05). O comprimento dos embriões do grupo CNG foi maior que dos embriões do grupo CG (P&LT;0,05), entre os dias 28 e 34. Não foi detectada diferença de abundância relativa das proteínas VEGF e VEGF-R2 entre os quatro grupos estudados, porém quando os grupos de gestações normais (CG e CNG) foram comparados com os grupos de gestações alteradas (CAG e CPCL) foi detectada maior abundância relativa para o fragmento de 75 kDa da proteína do VEGF-R2 no grupo de gestações alteradas. A hipótese central do estudo, que afirma que as alterações morfovasculares do útero gestante durante o primeiro mês são moduladas em diferentes graus de forma dependente à qualidade de desenvolvimento do concepto foi confirmada. Por fim, este estudo proporcionou um melhor entendimento da fisiologia endócrina, morfológica e vascular das gestações normais e alteradas de embriões clonados por SCNT durante o primeiro mês gestacional, fornecendo base para novos estudos sobre o desenvolvimento e manutenção da gestação inicial em bovinos. / Cloning by nuclear transfer of somatic cells (SCNT) in cattle is an inefficient biotechnique. However, it is a very important tool for research in developmental biology. Previous studies from our lab have identified three gestational phenotypes of bovine clones: (1) Clone normal gestation (CNG) - presence of embryo (EP = embryo proper), embryonic vesicle (EV) and corpus luteum (CL); (2) Clone anembryonic gestation (CAG) - presence of EV and CL and no EP; (3) Recipient presenting only a persistent CL (CPCL). Embryo donor cows were synchronized by superovulation protocol (SOV) and artificially inseminated, embryos obtained after seven days of ovulation were transferred to the control group (CG). This study aimed to investigate whether modulation of the morphological and vascular abnormalities of the uterus by the presence of the cloned conceptus is different between the three gestational clone phenotypes and control. The central hypothesis was that the morphovascular characteristics of the uterus are modulated differently in the three gestational phenotypes of embryos cloned by SCNT and control gestation. Nellore cows were synchronized and used as embryo recipients. Blood collections for progesterone analysis and ultrasound examinations in B and Doppler modes for analysis of uterine morphology and vascularization were performed every two days from day 6 to day 30. Between 31-36 days, the recipients were slaughtered and the uteri were collected for in situ analyzes. The symmetry between horns, the degree of caruncle and EV development were measured and endometrial samples were collected for relative quantification of vascular endothelial growth factor (VEGF) and its receptor type 2 (VEGF-R2) by western blotting. A total of 212 estrous cycle synchronizations were performed, 79 recipients cows received clone embryos by SCNT and 49 embryos produced in vivo. At 25 days after ovulation the conception rates by group were: CNG = 15.1% (12/79), CAG = 2.5% (2/79), CPCL = 8.8% (7/79), and CG = 24.4% (10/49). Two pregnant cows Tabapuã (Bos taurus indicus) of CAG phenotype from another experiment were included in the analyzes. Some recipients were excluded from the experiment due to gestational losses occurring before the time of slaughter, remaining seven recipients in CNG group, three in CAG, four in CPCL and nine in CG. Only the CG group had a difference in vascular perfusion between the ipso and contralateral uterine horns (P&LT;0.05). In relation to the ipsilateral horn, the CG and CNG groups presented higher vascular perfusion compared to the CPCL group from day 24 to 30 (P&LT;0.05). However, with the average of endometrial vascular perfusion scores of both uterine horns, the CNG group presented higher values in compared to the CAG and CPCL groups on days 24 and 30. The vascular resistance index (RI) of the uterine arteries confirmed the subjective data of vascular perfusion between horns. The ipsilateral horn of the CG group presented lower RI in compared to the contralateral on days 22, 24, 28 and 30 (P&LT;0, 05) and the CNG and CPCL groups did not show this difference between horns (P&GT;0.05). Among groups, the RI in CG and CAG was lower than in the CPCL on day 30 (P&LT;0.05). The blood progesterone (P4) concentration was lower in the CPCL group than in the CG and CNG groups on days 18 and 26 (P&LT;0.05). P4 reached values close to 8 ng/ml after day 22 in the CG and CNG groups, and in the CPCL group the values were lower than 6 ng/ml after day 14. In situ analyzes revealed a higher frequency of uterine horn asymmetry in the CG group compared to the CNG, CAG and CPCL groups; the CNG group had a higher frequency of caruncles and EV development in the two uterine horns compared to the CAG and CPCL groups (P&LT;0.05), not differing from the CG group (P&GT;0.05). The length of the embryos of the CNG group was higher than that of the embryos of the CG group (P&LT;0.05) between days 28 to 34. No difference was detected in the relative abundance of VEGF and VEGF-R2 proteins among the four groups, but when the normal gestation groups (CG and CNG) were compared with the altered pregnancies groups (CAG and CPCL) a greater relative abundance was detected for the 75 kDa fragment of the VEGF-R2 protein in the group of altered pregnancies. The central hypothesis of the study, which states that the morphovascular changes of the pregnant uterus during the first month are modulated in different degrees depending on the quality of development of the concept was confirmed. Finally, this study provided a better understanding of the endocrine, morphological and vascular physiology of normal and altered embryos of cloning by SCNT during the first gestational month, providing a basis for new studies on the development and maintenance of initial gestation in cattle.
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Caracterização de proteoglicanos do útero de camundongos durante o ciclo estral e em animais ovarectomizados: análise dos efeitos da castração e da reposição hormonal. / Characterization of proteoglycans in the mouse uterus during the estrous cycle and in ovariectomized animals: analysis of the effects of castration and hormone replacement.

Renato de Mayrinck Salgado 14 August 2009 (has links)
A matriz extracelular (MEC) dos tecidos uterinos é altamente remodelada na gestação de camundongos. Os objetivos deste estudo foram avaliar a influência dos hormônios ovarianos estrógeno (E2) e progesterona (P4) sobre a estrutura dos tecidos uterinos de camundongo e a deposição dos proteoglicanos decorim, biglicam, fibromodulim, lumicam, perlecam e versicam nestes tecidos. Para isto, utilizamos um modelo de castração e reposição hormonal, e o ciclo estral como parâmetro fisiológico. Verificamos que, como na gestação, durante o ciclo estral ocorre intensa remodelação na estrutura e na MEC dos tecidos uterinos. Verificamos ainda que a resposta aos hormônios ovarianos é: compartimento-específica; hormônio-específica e molécula-específica. Notável foi a modulação do versicam pelos hormônios ovarianos. P4 induz a deposição de versicam no estroma, enquanto o miométrio responde apenas a E2. A modulação dos proteoglicanos pelos hormônios ovarianos mostra a relevância destas moléculas para a composição de um ambiente uterino propício para o desenvolvimento do embrião. / The extracellular matrix (ECM) of the mouse uterine tissues is highly remodeled during pregnancy. The aim of this study was to demonstrate the influence of estrogen (E2) and progesterone (P4) on the uterine structure and on the deposition of the proteoglycans decorin, biglycan, fibromodulin, lumican, perlecan and versican in these tissues. For that purpose, we used a model of castration e hormone replacement as main strategy, and the estrous cycle as physiological parameter. We verified that, as in pregnancy, during the estrous cycle an intense remodeling occurs on the structure and the ECM of the uterine tissues. We also showed that the response to the ovarian hormones is: compartment-; hormone- and molecule- specific. Noteworthy was the modulation of versican by the hormones: P4 induces the deposition of versican in the stroma, whereas the myometrium responds only to E2. The modulation of proteoglycans by the ovarian hormones indicates the relevance of these molecules for the composition of a proper microenvironment for embryo development.
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Rôles de l'adiponectine à l'interface foeto-maternelle humaine au cours du premier trimestre de grossesse / Adiponectin roles at the human fetal-maternal interface in first-trimester of pregnancy

Duval, Fabien 10 November 2017 (has links)
L’implantation embryonnaire repose sur une synchronisation spatio-temporelle entre un placenta fonctionnel et un endomètre réceptif. La réceptivité endométriale requiert la différenciation des cellules stromales en cellules déciduales sous l’effet des hormones ovariennes (œstrogènes et progestérone). Le placenta est un organe transitoire constitué de deux types cellulaires. Le cytotrophoblaste villeux est responsable des échanges fœtaux maternels et de la fonction endocrine du placenta. Le cytotrophoblaste extravilleux présente des propriétés invasives et assure ainsi l’ancrage du placenta dans l’endomètre maternel. Un dialogue paracrine complexe entre les cellules placentaires et endométriales s’établit au cours des premières étapes de l’implantation.L’adiponectine est une adipokine produite majoritairement par le tissu adipeux. Elle contrôle le métabolisme glucido-lipidique et joue le rôle d’hormone insulino-sensibilisatrice. Dans de nombreux tissus, l’adiponectine exerce des effets anti-prolifératifs, pro-invasifs et pro-différenciants. L’adiponectine et ses récepteurs ADIPOR1 et ADIPOR2 sont présents à l’interface fœto-maternelle. Le placenta et l’endomètre sont donc des tissus cibles de l’adiponectine.Au cours de ce travail, nous nous sommes intéressés aux effets directs de l’adiponectine à l’interface foeto-maternelle au cours du premier trimestre de grossesse.Dans une première partie, nous avons observé que l’adiponectine exerce des effets anti-différenciants et anti-invasifs dans les cellules stromales endométriales.Dans un second temps, nous avons démontré que l’adiponectine favorise la production de glycogène dans les cellules déciduales. Inversement, l’adiponectine semble limiter l’entrée du glycogène dans les cellules placentaires. Ces résultats démontrent que l’adiponectine pourrait contrôler la nutrition histiotrophe du foetus.Dans une dernière partie, nous avons observé que l’adiponectine diminue l’expression des transporteurs de nutriments et exerce une action pro-apoptotique dans le trophoblaste villeux. Ces derniers résultats pourraient permettre de mieux comprendre le rôle de l’adiponectine dans les pathologies placentaires telles que le retard de croissance intra-utérin qui se caractérise par une diminution du poids foetal et une augmentation de l’apoptose des cellules trophoblastiques.L’ensemble de ces résultats montre que l’adiponectine est un acteur clé du dialogue foeto-maternel au cours de la grossesse précoce en contrôlant la maturation d’un endomètre fonctionnel et en régulant les échanges nutritifs transplacentaires. / Embryo implantation requires a spatiotemporal synchronization between a functional placenta and a receptive endometrium. Endometrium receptivity based on the differentiation of stromal cells into decidual cells, under the influence of ovarian hormones (estrogens and progesterone). The placenta is a transient organ composed of two cell types. Villous trophoblast ensures fetal-maternal exchanges and the endocrine functions. Extravillous trophoblast acquire an invasive phenotype resulting in the placenta anchoring in the endometrium. Then, a complexe paracrine dialog between placental cells and endometrial cells is established during the first stages of the embryo implantation.Adiponectin is an adipokine predominantly produced by the adipose tissue. This cytokine has an important role in the control of energy metabolism and displays an insulin-sensitizing action. In some cell types, adiponectin limits proliferation, but promotes invasion and differentiation. Adiponectin and its receptors ADIPOR1 and ADIPOR2, are expressed at the fetal-maternal interface. Thus, endometrium and placenta are adiponectin targets.In this work, we aimed to determine adiponectin direct effects at the human fetal maternal interface during the first trimester of pregnancy.In a first part, we observed that adiponectin limits differentiation and invasion in endometrial stromal cells.In a second part, we showed that adiponectin promotes glycogen production by decidual cells. Conversely, adiponectin seems to limit glycogen uptake by placental cells. These results demonstrate that adiponectin could regulate histiotrophic nutrition to the fetus.In a last part, we demonstrated that adiponectin down-regulates the expression of nutrient transporters and promotes apoptosis in villous trophoblast. These last results could help to better understand the adiponectin roles in some placental pathologies, as intrauterine growth restriction, characterized by a decreased fetal weight and a enhanced trophoblastic apoptosis. Altogether, these results demonstrate that adiponectin is a key regulator of the fetal-maternal dialog by controlling the differentiation of a functional endometrium and by regulating transplacental nutrient exchanges.
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Rôle de la voie hippo dans la physiologie utérine chez la vache

Blais, Étienne 08 1900 (has links)
L'utérus est un organe hautement dynamique, qui subit des changements morphologiques durant le cycle œstral sous l'influence des hormones sexuelles. Ces adaptations sont essentielles à l’homéostasie utérine et résultent d’une régulation minutieuse de la prolifération, de la différenciation et de la survie cellulaire par de nombreuses voies de signalisation. Nous avons émis l'hypothèse que la voie Hippo est impliquée dans l'homéostasie utérine chez l’espèce bovine, et nous avons tenté de déterminer les variations de ses constituants. Des biopsies de l'endomètre et des échantillons de sang ont été obtenus aux jours 0, 3 et 10 du cycle chez 14 vaches. Les concentrations sanguines de progestérone et d’œstrogène ont confirmé la progression du cycle œstral chez cinq vaches. Des analyses immunohistochimiques, Western Blot et RT-PCR ont été réalisées sur les biopsies afin d’évaluer la variation des composantes de la voie Hippo et de ses gènes cibles. Nous avons démontré la présence de YAP et de TAZ dans l'endomètre bovin à tous les moments du cycle œstral. Elles présentaient une expression cytoplasmique dans l'épithélium glandulaire, et présentaient une expression nucléaire dans le stroma à J0 et J10 et dans l'épithélium luminal à J3. Nous avons également noté une tendance à l'augmentation des concentrations de la forme phosphorylée de YAP au jour 3 du cycle œstral par rapport aux jours 0 et 10. Cette augmentation a été corrélée à une diminution de l'expression du gène CTGF au jour 3 par rapport aux autres jours du cycle œstral. En conclusion, nous avons démontré que la voie Hippo est exprimée différentiellement dans l'utérus bovin au cours du cycle œstral. / The uterus is a highly dynamic organ that changes morphologically under the influence of sexual hormones during the estrous cycle. These adaptations are essential for the proper function of the uterus and are due to the careful regulation of cell proliferation, differentiation, and apoptosis by numerous signaling pathways. We hypothesized that the Hippo pathway is implicated in uterine homeostasis in cattle, and we aimed to determine the variation of its canonical constituents during the bovine cycle. Endometrial biopsies and blood samples were obtained on days 0, 3, and 10 of the cycle in 14 cows. Progesterone and estrogens blood concentrations were measured and confirmed the status of the oestrus cycle in five cows. Immunohistochemistry, western blot, and RT-PCR were then performed on their endometrial biopsies to evaluate the Hippo components and targeted genes. Our results showed the presence of YAP and TAZ in the bovine endometrium at all time point. Both proteins displayed cytoplasmic expression in the glandular epithelium while exhibiting nuclear expression in the stroma on D0 and D10 and in the luminal epithelium on D3. We also noted a tendency for an increased amount of phosphorylated YAP during day 3 of the estrous cycle compared to days 0 and 10. It was correlated with a decreased expression of CTGF (Hippo target gene) on day 3 compared to the other day of the cycle. In conclusion, we can confirm that Hippo is differentially expressed in the bovine uterus during the estrous cycle.

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