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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.
121

The child’s best interest : Perspectives of gamete recipients and donors

Isaksson, Stina January 2015 (has links)
Background: An increasing number of couples turn to treatment with oocyte or sperm donation, but there is limited knowledge regarding the consequences of these treatments in a program using identifiable donors. Aim: The overall aim was to study information-sharing among heterosexual couples following identity-release gamete donation. A further aim was to study donors’ attitudes towards future contact with donation offspring. Methods: The four studies were part of The Swedish Study on Gamete Donation; a prospective, longitudinal study of donors and recipients of donated oocytes and sperm. Study I and II had a quantitative approach with recipients of donated oocytes or sperm participating through questionnaires at start of treatment, two months after the first treatment and when their child was 1-4 years old. Study III was a qualitative interview study with 30 parents following sperm donation with school-aged children. Study IV had a quantitative approach with oocyte and sperm donors participating through questionnaires 5-8 years post-donation. Results: Study I revealed that the recipients of donated gametes in general were open about their treatment with the people around them and supported disclosure to offspring regarding his/her genetic origin. Study II reported that most of those who became parents following donor conception intended to share information about the donation with their offspring and some had already started the information-sharing process with their young child. Study III described information sharing with the offspring to be a process of several levels, revealing various amounts of information about the way of conception. The parent was seen to be the owner of the process and moving the process forward with different aspects and the reactions of the offspring serving as driving or impeding forces of the process. Study IV reported that a majority of the gamete donors seem to have a positive or neutral attitude towards a future meeting with a donation offspring. Conclusion: The present thesis suggests that there is a trend towards more openness among recipients of donated gametes in Sweden. It also points out that most recipients and donors within the Swedish gamete donation programme acknowledge the child’s right to his/her genetic origin and have the best interest of the child in mind.
122

A FUNCTIONAL, COMPARATIVE AND CLINICAL ANALYSIS OF SPERM-BORNE OOCYTE ACTIVATING FACTOR, PAWP

Aarabi, Mahmoud 01 October 2013 (has links)
Successful fertilization depends upon the activation of metaphase II arrested oocytes by sperm-borne oocyte activating factor (SOAF). Failure of oocyte activation is considered as the cause of treatment failure in a proportion of infertile couples. SOAF induces the release of intracellular calcium in oocyte which leads to meiotic resumption and pronuclear formation. Calcium release is either in the form of single calcium transient in echinoderm and amphibian oocytes or several calcium oscillations in ascidian and mammalian oocytes. Although the SOAF attributes are established, it is not clear which sperm protein(s) play such role. Sperm postacrosomal WW binding protein (PAWP) satisfies a developmental criteria set for a candidate SOAF. This study shows that recombinant human PAWP protein or its transcript acts upstream of calcium release and fully activates the amphibian and mammalian oocytes. Interference trials provided evidence for the first time that PAWP mediates sperm-induced intracellular calcium release through a PPXY/WWI domain module in Xenopus, mouse and human oocytes. Clinical applications of PAWP were further investigated by prospective study on the sperm samples from patients undergoing intracytoplasmic sperm injection (ICSI). PAWP expression level, analyzed by flow cytometry, was correlated to ICSI success rate and embryonic development. This study also explored the developmental expression of the other SOAF candidate, PLCζ in male reproductive system and its function during fertilization. Our findings showed for the first time that PLCζ most likely binds to the sperm head surface during epididymal passage and is expressed in epididymis. We demonstrated that PLCζ is also compartmentalized early in spermiogenesis and thus could play an important role during spermiogenesis. Detailed analysis of in vitro fertilization revealed that PLCζ disappears from sperm head during acrosome reaction and is not detectable during sperm incorporation into the oocyte cytoplasm. In conclusion, this dissertation provides evidence for the essential non-redundant role of sperm PAWP in amphibian and mammalian fertilization; recommends PAWP as a biomarker for prediction of ICSI outcomes in infertile couples; and proposes that sperm PLCζ may have functions other than inducing oocyte activation during fertilization. / Thesis (Ph.D, Anatomy & Cell Biology) -- Queen's University, 2013-09-29 23:45:35.395
123

Role of TrkB in neonatal ovary development

Lannagan, Tamsin R. M. January 2009 (has links)
The signalling cascade induced by the binding of neurotrophins (NGF, BDNF, NT3 and NT4) to their high-affinity tyrosine kinase receptors (TrkA, B and C) is well documented to be important for neuronal cell survival, proliferation and differentiation. Evidence has accumulated demonstrating the importance of these signalling pathways in nonneuronal tissues, including the ovary where all neurotrophins and their receptors are expressed. In the mouse, effects on ovulation have been demonstrated but the role of Trk signalling in neonatal ovary development is less clear. Previous work had found that TrkB expression is upregulated at the time of follicle formation in the mouse and transgenic mice null for the TrkB receptor demonstrate significant loss of oocytes neonatally (TrkB knockouts, KO, die shortly after birth). This thesis examines the phenotype of the TrkB KO using morphological, histological and surgical techniques with the aim being to further investigate the role of TrkB signalling in oocyte survival, and to contribute to our understanding of neonatal ovary development. The main questions addressed are: 1) what developmental defects are occurring on a morphological level that result in the phenotype of the TrkB KO; 2) can these defects be quantified; and 3) what are the longterm survival prospects for TrkB KO oocytes. Morphological assessment revealed that TrkB KO ovaries exhibit poorer follicle health than their Controls and this was confirmed by assessment of basement membrane (BM) composition. TrkB KO brain and kidney were also assessed and found to have similarly affected BM. It is well known that cells require contact with the BM to maintain survival, thus it is postulated that TrkB signalling contributes to oocyte survival through regulation of the BM. Due to the postnatal lethality of the mutation, TrkB KO ovaries were transplanted to ascertain long-term oocyte survival. Unexpectedly it was found that TrkB KO oocytes are able to survive and follicles grow as well as they do in the Control transplants. Consequently, the in vivo effect has to be indirect. It is known that oocytes in the neonatal ovary undergo an increased rate of cell death but it is not known how the cell debris is removed. A novel observation of a neonatal ovarian immune response has been made in this thesis and is postulated to be a physiological mechanism for cell debris clearance. In conclusion, this thesis has demonstrated that signalling through TrkB has an effect on regulating BM in the ovary and other organs, but that surprisingly it has an indirect effect on oocyte survival.
124

Etude des régulateurs d’apoptose de la famille Bcl-2 au cours du développement embryonnaire précoce humain / Study of anti- and pro-apoptotic Bcl-2 family genes during human early embryonic development

Boumela, Imene 03 September 2012 (has links)
Des signes d'apoptose, une forme de suicide cellulaire programmé, ont été décrits dans les gamètes et l'embryon préimplantatoire de nombreuses espèces de mammifères y compris l'homme, à la fois in vitro et in vivo. Parce que le développement embryonnaire serait lié à un équilibre entre prolifération et mort cellulaire, l'étude du contrôle génétique de l'apoptose dans les embryons préimplantatoires est d'une importance considérable. Par ailleurs, on sait que la qualité des gamètes (en particulier des ovocytes) influencerait leur propre survie mais également le développement embryonnaire précoce. Les régulateurs d'apoptose appartenant à la famille Bcl-2 occupent une place centrale dans les voies de décision de vie ou de mort cellulaire. Dans le premier volet de ce travail de thèse, nous avons analysé l'expression des membres de la famille Bcl-2 lors de la transition ovocyte-embryon au troisième jour (J3) et montré que les trois sous-groupes de la famille Bcl-2 présentent un profil d'expression dynamique tout au long du développement embryonnaire précoce humain. La régulation des niveaux d'expression de ces gènes au cours du développement embryonnaire précoce pourrait donc s'avérer cruciale pour le contrôle de la survie embryonnaire, notamment sous des conditions de culture suboptimales. Dans le second volet, nous nous sommes intéressés à l'analyse du transcriptome au cours du développement embryonnaire précoce humain, et plus particulièrement lors de la spécification du trophectoderme. La confrontation du transcriptome des embryons à J3 avec celui des cellules du trophectoderme nous a permis de mettre en évidence des processus moléculaires qui pourraient jouer un rôle important lors de la différenciation du TE, tels que la stéroïdogenèse et les régulations épigénétiques. En plus de son intérêt fondamental, la connaissance de l'expression génique et des mécanismes moléculaires régulant des processus clés tels que l'apoptose et la différenciation cellulaire au cours du développement embryonnaire préimplantatoire peut permettre d'ouvrir des pistes de recherche diagnostique et thérapeutique intéressantes. / Apoptosis, a form of cell death by self-destruction, has been reported in gametes and preimplantation embryos both in vitro and in vivo. Recent evidence suggests that cell death processes can impact embryo developmental competence. Moreover, quality of the gametes (particularly of the oocytes) is relevant not only for their own survival but can also influence embryonic development during the early cleavage stages. Thus, the investigation of apoptosis-related genes and mechanisms in early embryos is crucial. Bcl-2 family proteins, through balanced interactions between pro- and anti-apoptotic members, play a pivotal role in controlling cell life and death. In a first part, we analyzed the expression patterns of Bcl-2 family members during the human oocytes-to-day 3 embryo transition and showed that several members were differentially regulated. The regulation of the expression levels of anti- and pro-apoptotic Bcl-2 family members during early embryonic development may therefore be crucial for the control of early embryo survival, especially under suboptimal culture conditions. In a second part, we were interested in studying the transcriptome during human early embryonic development, and particularly during the trophectoderm specification. The comparison of the transcriptome of embryos on day 3 with that of trophectoderm cells allowed us to identify new molecular processes that could play an important role during trophectoderm differentiation and development, such as steroidogenesis and epigenetic regulations. In addition to its fundamental interest, a better knowledge of gene expression and molecular mechanisms regulating key processes such as apoptosis and cell differentiation during human early embryonic development may provide new guides for diagnosis and therapeutic strategies.
125

La Yemanucléine de Drosophile est nécessaire à la méiose ovocytaire et l’assemblage de la chromatine paternelle dans le zygote / Drosophila Yemanuclein is required for meiosis in the oocyte and paternal chromatin assembly in the zygote

Algazeery, Ahmed 08 April 2013 (has links)
La reproduction sexuée repose sur deux processus fondamentaux : la méiose qui permet la formation des gamètes dont le génome est haploïde et la syngamie qui permet, après fécondation, de restaurer la diploïdie par fusion des deux noyaux parentaux haploïdes. Alors que la méiose repose respectivement sur le génome maternel pour l'ovocyte et paternel pour le spermatozoïde, la restauration de la diploïdie dans le zygote repose exclusivement sur le génome maternel. Si un pronucleus maternel compétent pour la réplication est formé au terme de la méiose ovocytaire, le génome paternel quant à lui, n'acquiert cette compétence que sous l'influence de facteurs maternels. En effet, à la fin de la méiose, le génome paternel est « empaqueté » avec des protamines qui le rendent inactif pour toute fonction biologique, en particulier la réplication. L'éviction des protamines et leur remplacement par des histones maternelles sont des étapes indispensables à l'acquisition par le génome paternel de sa compétence à la réplication, préalable à la syngamie. Tous ces événements doivent être extrêmement coordonnés afin de permettre à un premier noyau zygotique comportant les deux lots de chromosomes parentaux de se former et d'entrer dans le premier cycle mitotique.Notre laboratoire a identifié yemanuclein-alpha, aussi appelé yemanuclein (yem) dans un crible moléculaire pour des gènes exprimés spécifiquement dans la lignée germinale femelle, et son premier allèle muté yem1. Cette mutation ponctuelle (V478E) a été identifiée dans un crible génétique de « stérilité femelle ». Une descendance exceptionnelle observée chez les femelles yem1, présente la propriété inattendue d'être parthénogénétique. Cette propriété révèle un double défaut chez le mutant : dans le processus de méiose ovocytaire qui conduit à la formation d'un pronucleus maternel haploïde mais aussi dans la formation d'un pronucleus paternel compétent pour la syngamie. Mes travaux de thèse ont porté sur les deux aspects de la fonction de la Yemanucléine. En conjuguant des méthodes de génétique, de biochimie, et de biologie cellulaire, nous avons pu mettre en évidence des fonctions essentielles de la Yemanucléine dans les étapes initiales de la prophase méiotique de l'ovocyte de drosophile. Nous avons pu montrer que la Yemanucléine joue un rôle clé dans la recombinaison méiotique et plus particulièrement dans la fréquence et la cinétique d'apparition des cassures double brin. Son association au complexe synaptonémal et au complexe cohésine, tous deux connus comme étant nécessaires à la ségrégation chromosomique, est un élément clé de cette fonction.Outre cette fonction méiotique, la Yemanucléine, facteur maternel, est aussi requise pour l'assemblage de la chromatine du pronucleus paternel. Nous montrons dans ce manuscrit qu'elle joue ce rôle à travers son action dans un troisième complexe, en partenariat avec la protéine HIRA. Le complexe multiprotéique contenant la protéine HIRA est connu pour sa fonction de chaperon du variant de l'histone H3.3 et son rôle dans l'assemblage de la chromatine du pronucleus paternel. La Yemanucléine est le premier membre de la famille HPC2/UBN1 caractérisé. Son rôle dans l'assemblage des nucléosomes découplé de la réplication est décrit pour la première fois dans ce manuscrit. C'est aussi la première fois qu'une protéine spécifique de la reproduction est décrite pour son implication à deux étapes clés de ce processus. / Sexual reproduction relies on two key events: formation of cells with a haploid genome through meiosis and restoration of diploidy through syngamy in the zygote. Meiosis completion is supported exclusively by the maternal genome for the oocyte and the paternal genome for the sperm cell. In contrast diploidy restoration in the zygote is entirely dependent on maternal factors. At the end of meiosis the maternal pronucleus is competent for replication, whereas the paternal genome is packed with protamines. These proteins need to be removed in the zygote and replaced by maternally provided histones before the paternal genome acquires competence for replication, a prerequisite for syngamy. All these events must be highly coordinated to allow the first zygotic nucleus to form with the two sets of parental chromosomes and enter the first mitotic cycle. Our laboratory has identified yemanuclein-alpha, also called yemanuclein (yem) in a molecular screen for genes specifically expressed in the female germ line and its first mutant allele yem1, in a female sterile screen. The role played by yem not only in the meiotic process through which a haploid maternal pronucleus is formed but also in the zygotic process that makes a paternal pronucleus competent for syngamy, is underscored by the obtention of exceptional parthenogenetic progeny from yem1 mothers.My thesis work is precisely dedicated to the analysis of both aspects of Yemanuclein function: in the oocyte and the zygote. Using genetic, biochemical and cell biology methods we were able to uncover essential functions of Yemanuclein in early meiotic prophase in the Drosophila oocyte. Using yem1 allele (V478E), we could show its requirement for meiotic recombination especially for the frequency and timing of the double strand breaks formation. Yemanuclein association with two protein complexes, the Synaptonemal Complex (SC) and the Cohesin complex known to be required for proper chromosome segregation, supports these findings. Beyond its meiotic function, Yemanuclein is also required in the zygote for assembly of paternal pronucleus chromatin. This is achieved through a third complex that acts as histone H3.3 chaperone. In the present manuscript we identify Yemanuclein as a partner of HIRA in its role in H3.3 nucleosome assembly and deposition on the paternal pronucleus. Interestingly Yemanuclein is the first member of the HPC2/UBN1 protein family ever characterized. The role of Yem/ HPC2/ UBN1 in replication independent chromatin remodeling remained elusive until very recently. Our work is original in that it is the first to report on a role of one member of this family in oocyte meiosis and paternal chromatin assembly in the zygote.
126

Prospecção retrospectiva de lipídos presentes no líquido folicular associados ao potencial de desenvolvimento dos oócitos / Retrospective analysis follicular fluid lipids associated with the oocytes development potential

Andrade, Gabriella Mamede 28 January 2014 (has links)
A produção in vitro de embriões, no Brasil, ocupa lugar de destaque dentre as biotecnologias da reprodução animal e o atual desafio é torná-la cada vez mais acessível, para tanto, é fundamental aproximar os resultados de produção e sobrevivência dos embriões produzidos in vitro daqueles desenvolvidos naturalmente. Boa parte desta variação do potencial de desenvolvimento do embrião está relacionada à características do oócito. Há a possibilidade de essa capacidade estar relacionada ao perfil lipídico do líquido folicular e das células do folículo, neste sentido, este projeto teve como objetivo principal avaliar a correlação do potencial de desenvolvimento de oócitos com o conteúdo do perfil lipídico no líquido folicular e das células foliculares, baseado no sistema de ativação partenogenética, cultivo individual e analise retrospectiva. Não existe, até o momento, uma caracterização detalhada do microambiente folicular, um componente importante dos fluídos são os lipídios e recentemente tem sido demonstrado que eles estão envolvidos em vários aspectos do metabolismo além de também funcionarem como moléculas sinalizadoras ou até mesmo serem capazes de induzir modificações na cromatina. Os íons oriundos do estudo do perfil lipídico foram avaliados em comparação ao potencial de desenvolvimento do oócito. No conjunto de dados do MALDI observou-se maior concentração de triacilglicerídeos, principalmente contendo ácidos graxos como o oleico, linoleico e esteárico nos líquidos foliculares e células do folículo provenientes do ambiente folicular de oócitos que clivaram. No perfil lipídico do líquido folicular feito por LC-MS/MS os lipídios identificados foram de classes diversas, com participação expressiva no modo positivo de triacilgliceróis, fosfatidilcolinas, esfingomielinas, monoacildiacilglicerídeos entre outros e no modo negativo a classe lipídica que prevaleceu foi dos lipídios mitocondriais, as cardiolipinas. Também foram detectados lipídios citosólicos como o CE e alguns pouco descritos no líquido folicular como o PIP2 e PIP3, além disso, alguns lipídios foram característicos dos grupos clivados e blastocistos. O perfil lipídico do líquido folicular e das células do folículo é complexo e alguns lipídios deste ambiente tem potencial para serem biomarcadores de qualidade oocitária. / In vitro embryo production in Brazil occupies a prominent place among the animal reproduction biotechnology, the current challenge is to make it increasingly accessible so it is essential to approach the results of production and survival of in vitro produced embryos of those developed naturally. Much of this potential change of embryo development is related to the oocyte characteristics. There is the possibility of this ability is related to the lipid profile of follicular fluid and follicle cells , in this sense, this project aimed to evaluate the correlation of the oocytes development potential with the content of the lipid profile in follicular fluid and cells follicular, based on parthenogenetic activation , individual cultivation and retrospective analysis system. There isn\'t, to date, a detailed characterization of the follicular microenvironment, an important component of the follicular fluid and cels are the lipids and recently has been shown that they are involved in various aspects of metabolism in addition also function as signaling molecules or even be capable of inducing changes in chromatin. Derived ions from the study of lipid profile were evaluated compered with oocyte developmental potential. In MALDI dataset observed triacylglycerides higher concentration, mainly containing fatty acids such as oleic, linoleic and stearic acids in follicular fluid and follicle cells from follicular environment of cleaved oocytes. In follicular fluid lipid profile done by LC-MS/MS lipids were identified in diferent classes, with significant participation in positive mode of triacylglycerols, phosphatidylcholines, sphingomyelins, monoacildiacilglicerídeos among others and in negative mode prevailed lipid class was of mitochondrial lipids, the cardiolipin. Cytosolic lipids were also detected as CE and some little follicular fluid as described in the PIP2 and PIP3, and others lipids were characteristic of cleaved and blastocysts groups. The lipid profile of follicular fluid and follicle cells is complex and some of this lipid environment has the potential to be biomarkers of oocyte quality.
127

Avaliação anatomofuncional do sistema genital de fêmeas bubalinas (Bubalus bubalis), e suas implicações na múltipla ovulação e transferência de embriões / Anatomic and functional evaluation of buffalo (Bubalus bubalis) females genital system: implications on multiple ovulation and embryo transfer

Carvalho, Nelcio Antonio Tonizza de 31 March 2006 (has links)
Para aferir as prováveis causas da baixa taxa de recuperação de estruturas embrionárias em búfalas superovuladas, foram realizados 4 experimentos. No Exp.1, foram utilizados sistemas genitais de búfalas e de vacas tratadas para a indução de ovulações única ou múltipla (fatorial 2x2). Os sistemas genitais foram submetidos à morfometria, os ovidutos foram lavados para a recuperação dos oócitos e, posteriormente, foram encaminhados à histologia. A taxa de recuperação de oócitos e o volume dos ovários foram maiores para as vacas que para as búfalas (P<0,05). A área das fímbrias foi maior para as búfalas que para as vacas (P<0,05). As camadas musculares do infundíbulo e do istmo foram mais espessas para as búfalas que para as vacas (P<0,05) e, na ampola, não foi verificado diferença nesta medida entre as espécies (P>0,05). No Exp.2 foram utilizados ovidutos de búfalas e de vacas, tratadas para a indução de ovulação única. Os ovidutos foram abertos, colocados em meio de cultura com ou sem E2 (fatorial 2x2) e incubados por 30 minutos. Após o período de incubação, foram colocadas microesferas na superfície dos ovidutos para a aferição do movimento ciliar. As microesferas no infundíbulo direcionaram-se para o útero (P>0,05). Na ampola, direcionaram-se para o útero e para o ovário (P>0,05). No istmo das vacas, direcionaram-se para o ovário e no das búfalas, para o útero (P<0,05). A presença de E2 no meio de cultura não interferiu na direção do deslocamento das microesferas em nenhuma porção dos ovidutos de búfalas e de vacas. No Exp.3 foram utilizados ovidutos de búfalas e de vacas tratadas para a indução de ovulação única. Os ovidutos foram colocados em meio de cultura com ou sem E2 e receberam oócitos de búfalas ou de vacas (fatorial 2x2x2). Posteriormente, foram incubados por 24 horas e, após isso, foram lavados para a recuperação e contagem dos oócitos. O número e a taxa de recuperação de oócitos foi maior para as vacas que para as búfalas (P<0,05) e, estas variáveis não foram influenciadas pelo tratamento (P>0,05). Não foi verificada diferença no número de oócitos de búfalas ou de vacas recuperados (P>0,05). Os dados são indicativos de que o transporte de oócitos pelo oviduto de búfalas e de vacas independe da espécie do oócito e não é influenciado pelo E2. No Exp.4, búfalas e vacas foram tratadas para a indução de ovulações única ou múltipla. As fêmeas foram inseminadas e submetidas à laparotomia para a inserção no interior do oviduto de oócitos de búfalas ou de vacas (fatorial 2x2x2). Os sistemas genitais foram lavados 5 (oócitos de búfala) e 6 dias (oócitos de vaca) após a laparotomia para a recuperação das estruturas embrionárias. O número de estruturas embrionárias recuperadas foi maior para as vacas que para as búfalas (P<0,05) e, o número e a taxa de recuperação de estruturas embrionárias não foram influenciados pelo tratamento ou pela espécie dos oócitos (P>0,05). A espécie dos oócitos e o tratamento parecem não influenciar no transporte dos oócitos pelos ovidutos de búfalas e de vacas / In order to study the probable causes of the low embryo recovery rates in superovulated buffaloes, 4 experiments were performed. The experiment 1, consisted of treating buffaloes and cows in order to induce single or multiple ovulation (2x2 factorial). Genital systems were morphometrycally evaluated; oviducts were flushed in order to recover the oocytes, and subsequently submitted to histological examination. The oocyte recovery rate and the ovarian volume were higher for cows when compared to buffaloes (P<0.05). In contrast, fimbria area was higher for buffaloes than cows (P<0.05). Likewise, infundibulum and isthmus muscle layers were thicker in buffalo than cows (P<0.05). In addition, histological measurements were similar in cows and buffaloes (P>0.05). In the experiment 2, oviducts of buffaloes and cows treated to show a single ovulation, were dissected and placed in two media (with or without estradiol [E2] in a 2x2 factorial) and incubated for 30 minutes. After this period, microesferes were used to assess of the cilia movements. When placed in the infundibulum, microesferes moved toward the uterus (P>0.05). The microesferes in the ampulla moved towards the uterus and ovary in a similar fashion in both genetic groups (P>0.05). The microesferes in the isthmus, moved towards the ovary in cows; whereas, they moved towards the uterus in buffalo (P<0.05). There was no effect of media in the cilia movements at any portion of the oviduct neither in buffaloes or cows. In the experiment 3, oviducts of buffaloes and cows in the same conditions as in the previous experiment (single ovulation in with or without E2), received oocytes originated from buffaloes or cows (2x2x2 factorial). These oviducts were incubated for 24h and then flushed for oocyte recovery. The total number and the recovery rate of oocytes were higher for cows than for buffaloes (P<0.05). Interestingly, there was no effect of treatment in these same variables (P>0.05). The number of oocytes from buffaloes and cows that were recovered was similar (P>0.05). These results indicate that oocytes transport through the oviduct of buffaloes or cows does not depend on the oocyte specie and is not influenced by the E2. In the experiment 4, buffaloes and cows were treated in order to induce single or multiple ovulation. Females were inseminated and submitted to laparotomy in order to insert, inside the oviduct, oocytes of buffaloes or cows (2x2x2 factorial). Genital tracts were flushed on day 5 (oocytes from buffaloes) and on day 6 (oocytes from cows) after laparotomy for recovery of embryonic structures. The number of embryonic structures recovered was higher for cows when compared to the buffaloes (P<0.05). No effect of treatment or oocyte origin were found for the number or the rate of embryonic structures recovery (P>0.05). In conclusion, it is likely that type of oocyte and treatment do not affect transport of oocytes in the oviducts of buffaloes and cows
128

Análise do perfil de expressão gênica de oócitos bovinos advindos de complexos cumulus-oócito com diferentes qualidades morfológicas / Analysis of the gene expression profile of bovine oocytes derived from cumulus-oocyte complexes with different morphological qualities

Lemes, Rafaella Curvelano 17 May 2013 (has links)
A busca por melhores resultados nas biotecnologias reprodutivas leva a um estudo dos mecanismos fisiológicos básicos dos gametas e embriões em estágios iniciais. Entender como funciona o desenvolvimento destes, quais os nutrientes que eles precisam para se desenvolver in vitro e quais as condições ambientais necessárias permitem maiores taxas de sucesso. Tendo em vista a heterogeneidade dos complexos cumulus-oócito (COC) bovinos recuperados de ovários obtidos em frigorífico para a maturação in vitro e a relação entre oócito e células do cumulus nos resultados da produção in vitro de embriões, esse trabalho visa a identificação de fatores moleculares que possam explicar as melhores taxas de blastocistos obtidas por COCs com mais de três camadas de células do cumulus compactas e ooplasma homogêneo (COCI) quando comparados com COCs com menos de duas camadas de células do cumulus, com parte da zona pelúcida exposta e ooplasma homogêneo ou heterogêneo (COCIII). Para isso, COCI e III foram maturados in vitro separadamente, foram vortexados para retirada das células do cumulus e os oócitos foram submetidos a extração de RNA. O RNA foi amplificado em aRNA, marcado com biotina, fragmentado e hibridizado em microarray. Os arrays foram escaneados e os dados gerados analisados pelo métodos Significance Analysis of Microarrays e Rank Products em busca de genes diferencialmente expressos (DEG). A análise funcional in silico foi realizada com a ferramenta Ingenuity Pathway Analysis. Os resultados mostraram que o perfil de expressão dos oócitos de COCIII é diferente do perfil dos oócitos de COCI, como pode ser observado pelos 446 DEGs identificados, sendo 24 com expressão aumentada em oócitos de COCIII. Os genes com expressão alterada estão envolvidos em processos básicos da célula, como reassumição da meiose, metabolismo do oócito e maturação molecular, o que corrobora a ideia de que uma grande quantidade de células do cumulus interagindo com o oócito é crucial para a competência de desenvolvimento. / The researches for better results in reproductive biotechnologies have leading to studies of the basic physiological mechanisms of gametes and embryos in the early stages of developmental. Understand about their development, which nutrients they need and what environmental conditions are necessary to allow higher success rates. Because of the cumulus-oocyte complexes (COC) heterogeneous recovered from bovine ovaries obtained from an abattoir used for in vitro maturation and the relationship between oocyte and cumulus cells in the in vitro production of embryos, this study aims to identify molecular factors which might explain the improved rates of blastocyst obtained by COCs with more than three compact layers of cumulus cells and homogeneous ooplasm (COCI) compared with COC with less than two layers of cumulus cells, with part of the zona pellucida exposed and homogeneous or heterogeneous ooplasm (COCIII). For this, COCI and III were matured in vitro separately, their cumulus cells were removed and oocytes were subjected to RNA extraction. The RNA was amplified in aRNA, biotin labeled, fragmented and hybridized on microarray. The arrays were scanned and the data generated analyzed by the Significance Analysis of Microarrays and Rank Products methods in search of differentially expressed genes (DEG). In silico functional analysis were performed using Ingenuity Pathway Analysis. The results showed that the expression profile of COCIII oocytes is different from the profile of COCI oocytes. 446 DEGs were identified of which 24 presented increased expression in COCIII oocytes. Genes with altered expression are, in general, involved in the basic processes of the cell, as reassume of meiosis, metabolism of the oocyte and molecular maturation, which confirms the idea that a large amount of cumulus cells interacting with the oocyte is crucial for the development of competence.
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Estudo da maturação nuclear in vitro de oócitos de cães em meios suplementados com hormônios e co-cultivo em células homólogas da tuba uterina / In vitro canine oocyte nuclear maturation in hormonal supplemented mediums and homologal oviductal cells co-culture in dogs

Vannucchi, Camila Infantosi 01 December 2003 (has links)
As novas biotécnicas são ferramentas inovadoras no estudo da fisiologia da reprodução de cães, bem como na preservação do material genético de espécies ameaçadas de extinção. Tendo em vista, pois, a relevância de tais ferramentas, emprestou-se a este estudo o objetivo maior de avaliar os efeitos do 17-ß estradiol, progesterona e do co-cultivo em células da tuba uterina na maturação in vitro de oócitos de cães. Ovários de cadelas em anestro foram fatiados em PBS com 10% SFB. Os oócitos foram selecionados e divididos em 8 grupos: grupo 1 (sem suplementação hormonal), grupo 2 (20 µg/ml de 17-ß estradiol), grupo 3 (20 µg/ml de progesterona), grupo 4 (20 µg/ml de 17-ß estradiol e 20 µg/ml de progesterona), grupo 5 (co-cultivo em células da tuba uterina sem suplementação hormonal), grupo 6 (co-cultivo em células da tuba uterina + 20 mg/ml de 17-ß estradiol), grupo 7 (co-cultivo em células da tuba uterina + 20 µg/ml de progesterona) e grupo 8 (co-cultivo em células da tuba uterina + 20 µg/ml de 17-ß estradiol + 20 µg/ml de progesterona). O cultivo das células da tuba uterina foi realizado por no mínimo 48 horas previamente à adição dos oócitos. Para a maturação, utilizou-se TCM 199 suplementado com 2,5 µg/ml de FSH e 5 µg/ml de LH. Decorridas 48, 72 e 96 horas em estufa a 39&ordm;C, 5% de CO2 em ar e alta umidade, os oócitos foram fixados em paraformaldeído a 4% com Triton 10X e corados com Hoescht 33342 (10 µg/ml) em glicerol. O estágio de maturação nuclear (vesícula germinativa - VG, quebra da vesícula germinativa – QVG, metáfase I – MI, metáfase II – MII, degenerados ou não passíveis de determinação) foi avaliado em microscópio invertido equipado com luz ultravioleta e filtro de 365-420 de excitação/emissão. Os dados foram analisados mediante o PROC NPAR1WAY de análise de variância não paramétrica, sendo o efeito dos tratamentos verificado por meio do teste de Kruskal-Wallis, e as comparações múltiplas do teste de Wilcoxon com os tratamentos comparados dois a dois, considerando as diferenças significativas quando p<0,05. Verificou-se influência positiva da suplementação hormonal no desenvolvimento oocitário in vitro, particularmente com referência à adição de progesterona, associada ou não ao estrógeno. Não houve influência significativa do co-cultivo de células da tuba uterina na maturação oocitária em comparação aos meios de cultivo, sem presença de células epiteliais da tuba uterina, suplementados com hormônios esteróides. Conquanto sem significância estatística, verificou-se tendência de os oócitos, obtidos de cadelas em anestro, desenvolverem-se ao estágio de metáfase II após o período de maturação de 96 horas. Demonstrou-se, portanto, ser plenamente exeqüível o estudo da maturação de oócitos de cães em sistemas de cultivo in vitro a partir de ovários obtidos por ovário-histerectomia, tal estudo propicia, ademais, a pesquisa de características reprodutivas fisiológicas da espécie. / Recent biotechniques are innovative tools for the canine reproductive physiology research, as well as for assisted reproduction of endangered species. The aim of this study was to evaluate the effects of estradiol-17ß, progesterone and the co-culture with oviductal ephitelial cells on in vitro maturation. Ovaries from anestrous bitches were sliced in PBS with 10% FCS. Oocytes were selected and distributed in 8 groups: group 1 (no hormonal suplementation), group 2 (estradiol-17ß at 20 µg/ml), group 3 (progesterone at 20 µg/ml), group 4 (estradiol-17ß at 20 µg/ml + progesterone at 20 µg/ml), group 5 (co-culture in oviductal ephitelial cells without hormonal suplementation), group 6 (co-culture in oviductal ephitelial cells + estradiol-17ß at 20 µg/ml), group 7 (co-culture with oviductal ephitelial cells + progesterone at 20 µg/ml) and group 8 (co-culture with oviductal ephitelial cells + estradiol-17ß at 20 µg/ml + progesterone at 20 µg/ml). Oviductal ephitelial cells culture was performed at least 48 hours prior to oocyte co-culture. For in vitro maturation, TCM 199 supplemented with FSH (2.5 &micro;g/ml) and LH (5 &micro;g/ml) was utilized. After periods of 48, 72 and 96 hour at 39ºC in humidified atmosphere of 5% CO2 in air, oocytes were fixed with Triton-X10 in paraformaldehyde at 4% and and stained with Hoescht 33342 (10 µg/ml) in glycerol. Oocytes were examined through an inverted fluorescence microscope equipped with a 365-420 nm wavelength excitation/emisson filter. Nuclear maturation was classified according to chromatin configuration as: germinal vesicle stage (GV), germinal vesicle break down (GVBD), metaphase I (MI), metaphase II (MII) and degenerated and unidentifiable oocytes. Data was evaluated through PROC NPAR1WAY of non parametrical variance analysis and treatment was verified by the Kruskal-Wallis test and the Wilcoxon test for multiple comparisions. Differences were considered significant at p<0.05. Positive influence of hormonal supplementation for oocyte development rates was verified, particularly with respec to progesterone. No significant influence of oviductal cells co-culture was however verified. In addition, a tendency of the oocytes reaching metaphase II in the 96 hour period was observed. Therefore, the study of canine in vitro oocyte maturation is feasible and provides an important tool for reproductive physiology research.
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Análise da expressão gênica diferencial dos receptores de estrógeno (er&alpha; e er&beta;) e progesterona (pr) em oócitos e células do cumulus nas diferentes fases do ciclo estral em cães / Analysis of differential gene expression of estrogen (er&alpha; and er&beta;) and progesterone (pr) receptors in oocytes and cumulus cells on different phases of the estrous cycle in dogs

Gonçalves, José Sergio de Arruda 17 August 2007 (has links)
O objetivo do presente estudo foi analisar a expressão gênica dos receptores de estrógeno (ER&alpha; e ER&beta;) e progesterona (PR) em oócitos e células do cumulus de cadelas nas diferentes fases do ciclo estral. Ovários de cadelas previamente avaliadas e submetidas à ovário-histerectomia foram fatiados, sob refrigeração, em PBS com 10% de SFB. No momento imediatamente pré-cirúrgico foi colhido sangue da cadela, que foi submetido posteriormente à dosagem de estradiol e progesterona. As cadelas foram agrupadas nas diferentes fases do ciclo estral de acordo com a avaliação prévia por colpocitologia, colposcopia e dosagem sérica de progesterona. Os oócitos recuperados após o fatiamento foram denudados mecanicamente. Oócitos e células do cumulus foram criopreservados separadamente e posteriormente foram submetidas a PCR em tempo real para quantificação relativa dos genes de interesse. A expressão gênica de ER&alpha;, ER&beta; e PR em oócitos e células do cumulus não foi diferente nas fases do ciclo estral. Foi possível, pela primeira vez, relatar a presença de ER&alpha; e ER&beta; em oócitos de cadelas. / The objective of the present study was to analyze the gene expression of estrogen (ER&alpha; and ER&beta;) and progesterone (PR) receptors in oocytes and cumulus cells on different phases of the estrous cycle in dogs. Ovaries from selected bitches were recovered after ovary-hysterectomy and sliced at low temperatures in PBS supplemented with 10% FCS. Immediately after surgery, blood samples were harvested for measurement of estrogen and progesterone serum concentration. Bitches were grouped within different phases of the estrous cycles, according to previous evaluation of colpocytology, colposcopy and serum progesterone levels. Oocytes recovered after slicing were mechanically denuded. Isolated oocytes and cumulus cells were cryopreserved and submitted to RT-PCR followed by a real time PCR for relative quantification of gene expression. Gene expression of ER&alpha;, ER&beta; and PR in oocytes and cumulus cells was not different among phases of the estrous cycles. For the first time it was possible to demonstrate ER&alpha; and ER&beta; in dog oocytes.

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