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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.
81

Avaliação da estimulação ovariana com uso de análogos do gnrh

Montenegro, Ivan Sereno January 2012 (has links)
Introdução: Novos medicamentos trouxeram um considerável aumento na chance de gravidez no momento em que a estimulação ovariana controlada permitiu aumentar o número de oócitos a serem recuperados e, consequentemente, um maior número de embriões para serem transferidos. Os análogos de hormônio liberador de gonadotrofina, em associação com gonadotrofinas, trouxeram a solução para um dos problemas da estimulação ovariana controlada: o pico precoce de hormônio luteinizante, que prejudicava a coleta de oócitos em torno de 20% dos casos. Rotineiramente, usamos o protocolo com agonista, mas a possibilidade do uso de antagonistas resulta em maior facilidade de manuseio pelo usuário, envolve um único menstrual ciclo e dispensa orientação para uso de drogas, no final do ciclo anterior. Assim, buscamos avaliar o uso dos dois protocolos e analisar seus resultados. Objetivos: Análise e comparação de dados entre dois protocolos de indução (longo com agonista e flexível com antagonista) em pacientes submetidas a técnicas de reprodução assistida na SEGIR – Serviço de Ecografica, Genética e Reprodução Assistida – Porto Alegre. Métodos: Estudo transversal comparando os resultados intermediários com o uso de dois diferentes protocolos de estimulação ovariana com de agonista versus antagonista do hormônio liberador de gonadotrofina para técnicas de reprodução assistida. A análise estatística dos dados recuperados (idade, índice de massa corpórea, número de oócitos recuperados, número de oócitos fertilizados, número de oócitos clivados, dose total de FSH utilizada e ocorrência de síndrome do hiperestímulo ovariano) foi realizada através de teste t de Student para dados paramétricos e análise de covariância para as variáveis dependentes, calculados com o programa SPSS 16.0. Resultados: Um total de 50 pacientes preencheram os critérios para inclusão no estudo entre janeiro e março no ano de 2010, sendo 25 em cada grupo. Houve diferença estatística apenas na idade média entre os grupos (p=0,031). Não houve diferença estatística para os demais dados analizados (índice de massa corpórea, número de oócitos recuperados, número de oócitos fertilizados, número de oócitos clivados e dose de FSH utilizada) entre os grupos. Não houve casos de síndrome do hiperestímulo ovariano. Conclusão: Ambos protocolos os são iguais em termos de resultados. O agonista tem vantagens sobre o agendamento do procedimento, mas leva muito tempo para começar a estimulação e tem a possibilidade de iniciar a medicação em uma paciente grávida. Somado a isso, temos a possibilidade de ter síndrome do hiperestímulo ovariano como complicação. No grupo antagonista, está claro a maior facilidade de uso da medicação e o início mais rápido da estimulação ovariana. / Background: New medications have brought a considerable increase in the chance of pregnancy at the time that controlled ovarian stimulation allowed an increase in the number of oocytes to be recruited and, consequently, a greater number of embryos to be transferred. The gonadotropin-releasing hormone analogues, in association with gonadotropins, brought the solution to one of the controlled ovarian stimulation's problems: the early peak of luteinizing hormone, which harmed the oocytes collection around 20% of the cases. We, routinely, used the agonist protocol, but the possibility of antagonists usage results in greater ease of handling by the user, involves a single menstrual cycle and dispensation guidance for drug use, at the end of the previous cycle. Thus we seek to evaluate the use of the two protocols and analyze their results. Objective: Analysis and compare data between two induction protocols (long agonist and flexible antagonist) in patients submitted an assisted reproduction technique in SEGIR – Serviço de Ecografia Genética e Reprodução assistida – Porto Alegre. Methods: Cross-sectional study comparing the intermediate results with the use of two different ovarian stimulation protocols with gonadotropin-releasing hormone agonist versus antagonist to assisted reproductive techniques. The statistical analysis of the retrieved data (age, body mass index, number of oocytes recovered, number of fertilized oocytes, number of oocytes cleaved, total dose of FSH used and occurrence of ovarian hyperstimulation syndrome) was performed by Student t test for parametric data and analysis of covariance for the dependent variables, calculated with the program SPSS 16.0. Results: A total of 50 patients, 25 in each group, met the criteria for inclusion in the study between January and March in the year 2010. There was statistically significant difference only in the middle ages between the groups (p = 0 .031). There was no statistical difference for the remaining data analyzed (body mass index, number of oocytes recovered, number of fertilized oocytes, number of oocytes cleaved and dose of FSH utilized) between the groups. There were no cases of ovarian hyperstimulation syndrome. Conclusion: Both protocols are equal in terms of results. The agonist has advantages about scheduling of the procedure, but it takes too long to start the stimulation and have possibility to start medication in a pregnant patient. Added to this, we have the possibility of getting the ovarian hyperstimulation syndrome as complication. In the antagonist group, is clear the ease-of-use of the medication and the fastest start of the ovarian stimulation.
82

Avaliação da estimulação ovariana com uso de análogos do gnrh

Montenegro, Ivan Sereno January 2012 (has links)
Introdução: Novos medicamentos trouxeram um considerável aumento na chance de gravidez no momento em que a estimulação ovariana controlada permitiu aumentar o número de oócitos a serem recuperados e, consequentemente, um maior número de embriões para serem transferidos. Os análogos de hormônio liberador de gonadotrofina, em associação com gonadotrofinas, trouxeram a solução para um dos problemas da estimulação ovariana controlada: o pico precoce de hormônio luteinizante, que prejudicava a coleta de oócitos em torno de 20% dos casos. Rotineiramente, usamos o protocolo com agonista, mas a possibilidade do uso de antagonistas resulta em maior facilidade de manuseio pelo usuário, envolve um único menstrual ciclo e dispensa orientação para uso de drogas, no final do ciclo anterior. Assim, buscamos avaliar o uso dos dois protocolos e analisar seus resultados. Objetivos: Análise e comparação de dados entre dois protocolos de indução (longo com agonista e flexível com antagonista) em pacientes submetidas a técnicas de reprodução assistida na SEGIR – Serviço de Ecografica, Genética e Reprodução Assistida – Porto Alegre. Métodos: Estudo transversal comparando os resultados intermediários com o uso de dois diferentes protocolos de estimulação ovariana com de agonista versus antagonista do hormônio liberador de gonadotrofina para técnicas de reprodução assistida. A análise estatística dos dados recuperados (idade, índice de massa corpórea, número de oócitos recuperados, número de oócitos fertilizados, número de oócitos clivados, dose total de FSH utilizada e ocorrência de síndrome do hiperestímulo ovariano) foi realizada através de teste t de Student para dados paramétricos e análise de covariância para as variáveis dependentes, calculados com o programa SPSS 16.0. Resultados: Um total de 50 pacientes preencheram os critérios para inclusão no estudo entre janeiro e março no ano de 2010, sendo 25 em cada grupo. Houve diferença estatística apenas na idade média entre os grupos (p=0,031). Não houve diferença estatística para os demais dados analizados (índice de massa corpórea, número de oócitos recuperados, número de oócitos fertilizados, número de oócitos clivados e dose de FSH utilizada) entre os grupos. Não houve casos de síndrome do hiperestímulo ovariano. Conclusão: Ambos protocolos os são iguais em termos de resultados. O agonista tem vantagens sobre o agendamento do procedimento, mas leva muito tempo para começar a estimulação e tem a possibilidade de iniciar a medicação em uma paciente grávida. Somado a isso, temos a possibilidade de ter síndrome do hiperestímulo ovariano como complicação. No grupo antagonista, está claro a maior facilidade de uso da medicação e o início mais rápido da estimulação ovariana. / Background: New medications have brought a considerable increase in the chance of pregnancy at the time that controlled ovarian stimulation allowed an increase in the number of oocytes to be recruited and, consequently, a greater number of embryos to be transferred. The gonadotropin-releasing hormone analogues, in association with gonadotropins, brought the solution to one of the controlled ovarian stimulation's problems: the early peak of luteinizing hormone, which harmed the oocytes collection around 20% of the cases. We, routinely, used the agonist protocol, but the possibility of antagonists usage results in greater ease of handling by the user, involves a single menstrual cycle and dispensation guidance for drug use, at the end of the previous cycle. Thus we seek to evaluate the use of the two protocols and analyze their results. Objective: Analysis and compare data between two induction protocols (long agonist and flexible antagonist) in patients submitted an assisted reproduction technique in SEGIR – Serviço de Ecografia Genética e Reprodução assistida – Porto Alegre. Methods: Cross-sectional study comparing the intermediate results with the use of two different ovarian stimulation protocols with gonadotropin-releasing hormone agonist versus antagonist to assisted reproductive techniques. The statistical analysis of the retrieved data (age, body mass index, number of oocytes recovered, number of fertilized oocytes, number of oocytes cleaved, total dose of FSH used and occurrence of ovarian hyperstimulation syndrome) was performed by Student t test for parametric data and analysis of covariance for the dependent variables, calculated with the program SPSS 16.0. Results: A total of 50 patients, 25 in each group, met the criteria for inclusion in the study between January and March in the year 2010. There was statistically significant difference only in the middle ages between the groups (p = 0 .031). There was no statistical difference for the remaining data analyzed (body mass index, number of oocytes recovered, number of fertilized oocytes, number of oocytes cleaved and dose of FSH utilized) between the groups. There were no cases of ovarian hyperstimulation syndrome. Conclusion: Both protocols are equal in terms of results. The agonist has advantages about scheduling of the procedure, but it takes too long to start the stimulation and have possibility to start medication in a pregnant patient. Added to this, we have the possibility of getting the ovarian hyperstimulation syndrome as complication. In the antagonist group, is clear the ease-of-use of the medication and the fastest start of the ovarian stimulation.
83

Clomifeno e letrozol para estimulação ovariana controlada em técnicas de reprodução assistida: revisão sistematizada e meta-análise / Clomiphene and Letrozole for controlled ovarian stimulation in assisted reproduction techniques: systematic review and meta-analysis

Tatiana Nascimbem Bechtejew 22 September 2017 (has links)
Objetivo: Avaliar as evidências disponíveis comparando a eficácia da estimulação ovariana (EO) com uso de citrato de clomifeno (CC) e/ ou letrozol (LTZ) para reduzir o consumo de FSH, em relação à estimulação ovariana padrão (EOP). Métodos: Realizamos uma revisão sistematizada e meta-análise de ensaios clínicos randomizados (ECRs) que compararam os desfechos reprodutivos na fertilização in vitro. As buscas foram realizadas em onze bancos de dados eletrônicos e avaliamos manualmente a lista de referência dos estudos incluídos e revisões similares. Nós estratificamos os resultados separando os estudos baseados no agente oral utilizado (CC ou LTZ) e nas características da mulher incluída (em que se espera e em que não se espera má resposta ovariana). Os desfechos avaliados foram risco relativo (RR) para nascimento vivo, gravidez clínica, aborto, e taxa de cancelamento de ciclo, Peto Odds Ratio (OR) para síndrome de hiperestímulo ovariano (SHO), e diferença média (MD) para número de óocitos captados e consumo de FSH (ampolas). Resultados: Foram incluídos 22 estudos nesta revisão. Considerando o grupo de mulheres em que se espera má resposta, a evidência sugere que o uso de CC durante a estimulação ovariana resulta em similares taxas de nascidos vivos (RR= 0,9, IC95% = 0,6 a 1,2, evidência de moderada qualidade) e de gravidez clínica (RR= 1,0, IC95% = 0,8 a 1,4, evidência de moderada qualidade); o uso de LTZ não causa alteração significativa no número de oócitos captados (MD= -0,4, IC95% = -0,9 a +0,1, evidência de alta qualidade). Considerando os estudos que avaliaram mulheres em que não se esperava má resposta, a evidência sugere que o uso de CC reduz o número de oócitos captados (MD= -4,6, IC95%= -6,1 a -3,0, evidência de alta qualidade) e o risco de SHO (Peto OR= 0,2, IC95%= 0,1 a 0,3, evidência de moderada qualidade), enquanto os resultados são semelhantes para taxas de nascidos vivos (RR= 0,9, IC 95% = 0,7 a 1,1, evidência de moderada qualidade) e de gravidez clínica (RR= 1,0, IC95% = 0,9 a 1,2, evidência de alta qualidade). Para os demais desfechos a qualidade das evidências foi baixa ou muito baixa. Conclusões: A utilização de CC em mulheres em que se espera má resposta tem a vantagem de alcançar resultados reprodutivos semelhantes com redução dos custos. Para as demais mulheres, o uso do CC tem a vantagem adicional de reduzir o risco de SHO, mas também reduz o número de oócitos captados. Mais estudos seriam necessários para avaliar o efeito do LTZ com o mesmo propósito. Estudos futuros devem ter como objetivo estudar a taxa de gravidez cumulativa por oócito captado, insatisfação da paciente e aceitação para repetir o ciclo se não engravidar, que são dados importantes para a tomada de decisões clínicas. / Objective: To assess the available evidence comparing effectiveness of ovarian stimulation (OS) using clomiphene citrate (CC) and/or letrozole (LTZ) for reducing FSH consumption compared with standard OS. Methods: We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) that compared the reproductive outcomes following in vitro fertilization. We searched eleven electronic databases and hand-searched the reference list of included studies and related reviews. We stratified the results separating the studies depending on the oral agent (CC or LTZ) and on the characteristics of the included women (expected poor ovarian response or other women). When combining the results of included studies, we assessed the relative risk (RR) for live birth, clinical pregnancy, miscarriage, and cycle cancelation, Peto Odds Ratio (OR) for OHSS, and mean difference (MD) for the number of oocytes retrieved and FSH consumption. Results: A total of 22 studies were included in this review. Considering women with expected poor ovarian response, the available evidence suggests that using CC for reducing FSH consumption during OS provide similar live birth (RR=0.9, 95%CI=0.6-1.2, moderate quality evidence) and clinical pregnancy rates (RR=1.0, 95%CI=0.8-1.4, moderate quality evidence); the use of LTZ doesn\'t cause a relevant change on the number of oocytes retrieved (MD=-0.4, 95%CI= -0.9 to +0.1, high quality evidence). Considering the studies evaluating other women, the available evidence suggests that using CC for reducing FSH consumption during OS reduces the number of oocytes retrieved (MD=-4.6, 95%CI=-6.1 to -3.0, high quality evidence) and the risk of OHSS (Peto OR=0.2, 95%CI=0.1-0.3, moderate quality evidence), while results in similar live birth (RR=0.9, 95%CI=0.7-1.1, moderate quality evidence) and clinical pregnancy rates (RR=1.0, 95%CI=0.9-1.2, high quality evidence). The quality of the evidence was low or very low for the other outcomes. Conclusion: The use of CC for reducing FSH consumption in women with expected poor ovarian response has the advantage of providing similar reproductive outcomes with reduced costs. For the other women, the use of CC for reducing FSH consumption has the additional advantage of reducing OHSS, but also reduces the total number of oocytes retrieved. More studies are necessary to evaluate the effect of LTZ for the same purpose. Future studies should aim on cumulative pregnancy per oocyte retrieval, patient dissatisfaction and agreement to repeat the cycle if not pregnant; which are important outcomes for clinical decisions.
84

Viability assessment of oocytes and embryos by means of Biodynamic Imaging

IIka M Lorenzo (8812349) 08 May 2020 (has links)
<p>Infertility is the disease of the reproductive system and is estimated to affect more than 10% of the people of reproductive age. Assisted reproductive technologies (ART) are methods designed to alleviate infertility problems. <i>In vitro </i>embryo production is part of most infertility treatments and the efficiency of ART is low due to the lack of reliable methods to measure embryo viability. In order to improve the success rate of ART procedures, the current study was designed to investigate the use of an optical analyzer technology known as the Biodynamic Imaging (BDI) system for viability assessment. BDI is a novel approach that is able to measure intracellular dynamic processes that are directly related to functional events. During a series of experiments, 13 different biomarkers of oocytes and embryos were monitored by the BDI microscope and used for machine learning and evaluation of BDI sensitivity. We monitored cellular mechanisms essential for proper embryo development such as (1) extrusion of first and second polar body (2) energy status and mitochondrial activity, and (3) viability of embryos with different cellular composition. We were able to identify several biomarkers that have the potential to indicate viability: (1) slope, (2) NSD, (3) Knee (4) Floor, and (5) R<sup>2</sup> could consistently differentiate between oocytes and embryos of different viability. In addition, the BDI microscope could successfully predict the energy status of embryos by identifying 4 biomarkers (Slope, Knee, Floor, and Dy). Finally, a lipidomic analysis was done to evaluate the lipid composition of oocytes with different cytoplasm integrities. This analysis demonstrated that there is a difference in lipid subclasses among oocytes with dark vs. light cytoplasm. The results indicate that the BDI is useful for viability assessment of oocytes and embryos and may be helpful for the improvement of the efficiency of assisted reproductive technologies.</p>
85

How the experiences of Infertility and In Vitro Fertilization and Embryo Transfer (IVF -ET) are understood by South African women attending fertility clinics.

Pedro, Athena January 2008 (has links)
Philosophiae Doctor - PhD / Infertility is currently a serious problem that is escalating, not only in South Africa, but also worldwide. In Cape Town, a culturally diverse, urban community of approximately 1000 couples are referred to the Groote Schuur Hospital Infertility Clinic annually. Although infertility is primarily regarded as a medical condition, the treatments have emotional effects on infertile couples due to the recurring highs and lows that often accompany treatments. This study aimed to qualitatively explore and understand the emotional and psychological experiences of infertility and its treatments (specifically In Vitro Fertilisation and Embryo Transfer). Social constructionism is based on the premise that realities are not constructed in a vacuum but rather undergo a process whereby the subjective and inter-subjective experiences over time and through cultural processes come to be regarded as truths. These truths become internalised and function as lenses through which we see ourselves, compose and invent ourselves accordingly, making sense of what would otherwise have been chaotic and meaningless experiences. Additional aims were to examine women's experiences of infertility care whilst undergoing treatment and describe their experiences of coping with infertility and In Vitro Fertilisation and Embryo Transfer (IVF-ET). Semi-structured, in-depth individual interviews were conducted with 21 women presenting with primary infertility at a fertility clinic. This study utilised an ethnographic case study design. The results of the study suggested that women perceived themselves as not conforming to a dominant belief system that promotes motherhood as the most important role for women. The women described their 'failure' to fulfill socio-cultural expectations as emotionally turbulent. Some of the psychological responses to infertility included feelings of disappointment, shock, denial, devastation, anger, frustration, sadness, inadequacy, poor self-image and self-esteem. The women's personal accounts of their experiences of In Vitro Fertilisation and Embryo Transfer (IVF-ET) revealed that they found the treatment to be highly stressful, with emotional bouts of anxiety, nervousness, excitement and optimism. A psychological synopsis of infertility and IVF-ET is infertility and IVF-ET presents. The fmdings in this study suggest the need for the incorporation of presented. This diagrammatic representation shows the intensity of the emotional rollercoaster that psychosocial intervention into infertility management. Greater attention to the psychological and emotional repercussions of infertility treatment could lead to a more personalised approach which, in turn, would optimise patient satisfaction and also prepare couples for the demands of the program by informing them about better ways of coping.
86

Devenir à long terme de couples traités par fécondation in vitro dans la cohorte DAIFI / Long-term outcome of couples treated by in vitro fertilization in the DAIFI cohort

Troude, Pénélope 21 June 2013 (has links)
Les études sur les couples traités par fécondation in vitro (FIV) ont jusqu’à présent porté essentiellement sur l’évaluation du succès en FIV. Très peu de données sont disponibles sur le devenir à long terme de couples traités par FIV. L’objectif de ce travail était d’estimer la fréquence de réalisation du projet parental à long terme, et d’étudier les facteurs associés aux interruptions précoces des traitements et aux naissances naturelles.L’enquête DAIFI-2009 a inclus 6 507 couples ayant débuté un programme de FIV en 2000-2002 dans l’un des 8 centres de FIV participant à l’étude. Les données médicales des couples et leur parcours dans le centre ont été obtenus à partir des dossiers médicaux des centres de FIV pour tous les couples. L’information sur le devenir des couples après le départ du centre a été obtenue par questionnaire postal auprès des couples en 2008-2009 (38% de participation 7 à 9 ans après l’initiation des FIV). L’étude des facteurs associés à la participation à l’enquête postale suggérait que la fréquence de réalisation du projet parental estimée sur les répondants seulement pourrait être biaisée. Les différentes méthodes mises en œuvre pour corriger la non réponse (pondération, imputation multiple) n’ont pas modifié l’estimation de la fréquence de réalisation du projet parental. Au total, 7 à 9 ans après l’initiation des FIV, 60% des couples ont réalisé leur projet parental de façon biologique, suite à un traitement ou suite à une conception naturelle. Lorsque les adoptions sont aussi prises en compte, 71% des couples ont réalisé leur projet parental. Après l’échec d’une première tentative de FIV, un couple sur 4 (26%) a interrompu les FIV dans le centre d’inclusion. Globalement, les couples avec de mauvais facteurs pronostiques ont un plus grand risque d’interrompre les FIV. Cependant, la proportion plus importante d’interruption parmi les couples avec une origine inexpliquée de l’infécondité pourrait s’expliquer par la survenue plus fréquente de naissance naturelle dans ce sous-groupe de couples. Parmi les couples n’ayant pas eu d’enfant suite aux traitements, 24% ont ensuite conçu naturellement en médiane 28 mois après l’initiation des FIV. Parmi les couples ayant eu un enfant suite aux traitements, 17% ont ensuite conçu naturellement en médiane 33 mois après la naissance de l’enfant conçu par AMP. Les facteurs associés aux naissances naturelles sont des indicateurs d’un meilleur pronostic de fertilité, particulièrement chez les couples sans enfant AMP.L’enquête DAIFI-2009 a permis d’apporter des informations sur le parcours à long terme des couples traités par FIV qui n’avait jusqu’à présent été que peu étudié, souvent sur de faibles effectifs et avec un suivi plus court. Ces résultats doivent apporter de l’espoir aux couples inféconds, puisque la majorité d’entre eux ont finalement réalisé leur projet parental, même si cela peut prendre de nombreuses années. / Until now, most studies of couples treated by in vitro fertilization (IVF) have been centered on IVF success. Very few data are available on the long-term outcome of these couples, including spontaneous conception and adoptions. This work aimed to estimate the long-term cumulative parenthood rate, and to study factors associated with early IVF discontinuation and with spontaneous live births.The DAIFI study is a retrospective cohort including 6,507 couples who began IVF in 2000-2002 in one of the eight participating French IVF centres. Medical data on all couples were obtained from centre databases. Information on long-term outcome after leaving the IVF center was collected by postal questionnaire sent to couples in 2008-2010 (7 to 9 years after IVF initiation, participation rate 38%). Study of factors associated with participation in the postal survey suggested that the cumulative parenthood rate estimated only in participants might be biased. The different methods used to correct for non-response bias (inverse probability weighting, multiple imputation) did not modify the estimation of the cumulative parenthood rate obtained with the complete case approach. Finally, 7 to 9 years after IVF initiation, the cumulative parenthood rate was estimated at 60%, including live births following IVF, other treatment or spontaneous conception. When adoptions were also considered, the cumulative parenthood rate reached 71%. After a first failed IVF cycle, just over one couple out of four (26%) discontinued IVF treatment. Globally, couples with poor prognostic factors had a higher risk of early discontinuation of IVF treatment. However, the higher proportion of early discontinuation observed among couples with unexplained infertility could be linked to a higher chance of spontaneous pregnancy in this subpopulation. Among couples who remained childless after treatment, 24% later had a spontaneous live birth (SLB), at a median of 28 months after the first IVF attempt. Among couples who had had a child during medical treatment, 17% later had an SLB, at a median of 33 months after the birth following medical treatment. Regarding factors associated with SLB, they can be viewed as indicators of a better fertility prognosis, especially among unsuccessfully treated couples.The DAIFI study has provided information on the long-term outcome of couples treated by IVF, which has until now been little studied, often on small samples and with a shorter duration of follow-up. These results should give hope to infertile couples as nearly three couples out of four finally became parents, even if it may take many years.
87

Análisis de diferentes factores que afectan al rendimiento de la inyección intracitoplasmática de espermatozoides (ICSI) en la especie porcina

García Roselló, Empar 06 May 2005 (has links)
La ICSI porcina es una herramienta con gran potencial aplicativo en diversos campos, entre los que destacan la producción de animales transgénicos, y la recuperación de razas en peligro de extinción. Aunque en la actualidad existen referencias de obtención de descendencia viva, el rendimiento es inferior al de otras especies, posiblemente debido al desconocimiento de las condiciones idóneas, y la dificultad de los cigotos para alcanzar el estadío de blastocisto in vitro. El presente trabajo se llevó a cabo para determinar diferentes factores que podrían afectar al rendimiento de la técnica, estudiando el efecto de 1) la secuencia de cultivo de los zigotos recién inyectados; 2) modificaciones en el sistema de MIV tradicional, y por último 3) la activación exógena del ovocito mediante la inyección de inositol trifosfato con el espermatozoide. El objetivo global de este estudio fue el de incrementar el rendimiento final de la ICSI en la especie porcina. / ICSI in pigs is a tool with an important applicable potential in diverse fields. One of this is the production of transgenic animals, and the conservation of endangered species. Even though there are some cases of living offspring, its output is still quite low comparing to other species, possibly due to unknown factors referring to ideal conditions for the development, and to the difficulty of the zygotes to reach the blastocyst stage in vitro. The goal of this study was to evaluate different factors affecting the ICSI performance. This was done by studying 1) the sequence of culture of the injected oocytes; 2) In vitro maturation (IVM) modifications, through meiotic inhibitors, such as roscovitine, and changes in IVM duration time, and finally 3) the exogenous oocyte activation through inositol triphosphate (InsP3) injection together with the sperm. The main objective of this study was to increase the final performance of ICSI in pigs.
88

Oxygen and the ovarian follicle : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Bioprocess Engineering at Massey University, Palmerston North, New Zealand

Redding, Gabe Peter January 2007 (has links)
The role oxygen plays in the developing ovarian follicle is of interest not only to the field of developmental biology but also to in-vitro fertilisation (IVF) technologists, as oxygenation of the oocyte is considered to be a potential determinant of oocyte competence. Oxygen transport through the developing ovarian follicle, and practical aspects of the analysis of oxygen in human follicular fluid were investigated in this work. Mathematical modelling of oxygen transport in the pre-antral, and antrallpreovulatory follicle revealed a number of interesting findings, Contrary to previous conclusions (Gosden & Byatt-Smith, 1986), oxygen can reach the oocyte in the small pre-antral follicle. Improved estimates of diffusion coefficients through the granulosa cell layer and the inclusion of fluid voidage in this layer showed that oxygen can also reach the oocyte in large pre-antral follicles. The amount of oxygen that reaches the oocyte in the pre-antral follicle is a function of its size and degree of vascularisation. Symmetrically distributed vascularisation is superior in achieving a well oxygenated follicle. However, the large pre-antral follicle will eventually reach a size beyond which it cannot grow without anoxic regions developing. The size at which this occurs is consistent with the size at which antrum formation is observed in human follicles. The model predicts that the follicle can avoid an anoxic state through antrum formation, and shows that the follicle develops in a way that is consistent with overcoming mass transport limitations. The oxygen status of the follicle during the antrallpre-ovulatory phase of growth requires that the volume of granulosa cells be balanced by the volume of follicular fluid. Further predictions suggest that oocyte respiration becomes sub-maximal at follicular fluid volumes below approximately 4m1, vascularisation levels below 38%, or fluid i dissolved oxygen levels below 5.1 ~01%. These values are consistent with observations in the literature. It was also shown that the measurement of follicular fluid dissolved oxygen levels could provide a simple measure of the respiratory status of the oocyte, and this may be superior to the measurement of follicular vascularisation which requires knowledge of more parameters. Methodology for the analysis of follicular fluid oxygen solubility and diffusivity was developed using a Clark oxygen electrode. Analysis of these parameters showed that they are similar to human plasma, and allowed the predictive uncertainty of the model to be reduced. Experimental studies into the effects of IVF aspiration on follicular fluid were carried out. Aspiration results in significant changes in the properties of follicular fluid. Dissolved oxygen levels rose 5 * 2 vol%, pH increased by 0.04 * 0.01 pH units, and temperature dropped by 7.7 * 1.3 "C. Mathematical modelling of blood contaminated follicular fluid also showed that contamination results in significant changes in the dissolved oxygen of the fluid. This suggests that if the composition of follicular fluid is to be determined (particularly dissolved oxygen), sampling andlor measurement of fluid must take place before the collection vial of the aspiration kit, and blood contamination must be eliminated. Based on this result, the design and testing of devices capable of reliable sampling andlor rneasurement of oxygen levels of follicular fluid was considered. This presents a continuing challenge, including the integration of routine follicular fluid oxygen measurement into clinical practice.
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Má dítě vzniklé uměle, z darovaných gamet, přirozené právo na poznání svých biologických rodičů? / Does the child born from donated gametes right to know its biological parents?

TOŠNEROVÁ, Jana January 2017 (has links)
This thesis deals with the issue of assisted reproduction, ethical aspects of infertility treatment and in particular looking for the answer to the question of whether they have children from donated gametes natural right to know their biological parents, the gamete donors. The diploma thesis is devoted to the topic of infertility and description of some of the methods of assisted reproduction. Emphasis is on the status of child from gamete donation, especially with regard to its natural right to know the donor. Children only have the right to know the donor of the gametes from which it originated in countries, where the donation is not anonymous.. For these countries, the Czech republic does not belong. Seeking an answer to the question whether it is these children's natural right to know the identity of the donor, is started from how the natiral law is understood in general and also from a bio-psycho-social needs that children have. The work also includes a description of an exploratory survey realized in one of the reproductive clinics. Through survey, Infertile couples commented on the topic of organ donation and the possibility to confer children the natural right to know their biological parents.
90

Estratégias para viabilizar o uso de sêmen congelado na inseminação artificial cervical de ovinos / Strategies to improve the use of frozen semen in the cervical artificial insemination of sheep

Casali, Renata 21 February 2014 (has links)
Made available in DSpace on 2016-12-08T16:24:17Z (GMT). No. of bitstreams: 1 PGCA14MA122.pdf: 692452 bytes, checksum: e25e927c8d8beb4236a0bb259e17524a (MD5) Previous issue date: 2014-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Oxidative stress and premature sperm capacitation, generated during cryopreservation of ram semen, reduces their viability, especially after cervical insemination. The use of seminal plasma (SP) and negative pressure have produced protection and the reversion of such damages. Two experiments evaluated these potential enhancers of cryotolerance, and a third experiment compared 2 methods of cervical AI. In experiment 1 ram semen was subjected to the treatments: (TC) control or negative pressure of 200mBar (P200); 500mBar (P500) and 800mBar (P800). In experiment 2, the PS from rams, stallions and bulls was lyophilized (L) and its protein measured. From each SP 600&#956;g of protein per mL was aded to the freezing diluent used, compounding the experimental groups: control (TC), ovine PS (PSLO), bovine PS (PSLB) and equine PS (PSLE). Experiment 3 evaluated 2 methods of AI, the superficial cervical AI (G1), and deep intrauterine or cervical AI with clamping the vaginal fornix (G2). The in vitro data were subjected to ANOVA and test T, and the pregnancy rate to the chi square test, all with 5% significance level. In the experiment 1 higher progressive motility (PM) was observed in TC (49%) compared to P200 (40.9%), P500 (38.9%) and P800 (38.9%) treatments. In PM during the test the thermal resistance (TTR), MP after percoll (PP), acrosome integrity (IAC), IAPP and membrane integrity (MI), there was no difference between the groups. In cleavage rate P800 (34.5%) was less than P200 (51.2%) and P500 (50.9%) did not differ from the control (44.3%). In conclusion the P500 is the most appropriate for use in ram semen cryopreservation, enabling high rates of cleavage after heterologous IVF, maintain membrane integrity. Experiment 2 evaluated MP, MPPP and cleavage rate after heterologous IVF in all groups, with the best group compared with the control in: CASA system; acrossoma integrity (FITC-PSA), membrane stability (M540), chromatin integrity (acridine orange), apoptosis (annexin) and potential of mitochondria (Mitotracker). Also the PSLE showed higher cleavage rate (71.37%), indicating a greater ability to oocyte penetration. The PSLE showed higher VCL (PC-163.5&#956;m/s, PSLE-186.2&#956;m/s) and ALH (PC9&#956;m PSLE-8.2&#956;m) in CASA evaluation, compared to control. In flow cytometry the annexin test revealed a greater amount of non-apoptotic viable cells in PSLE (38.9%), compared to TC (32.1%). In experiment 3 there was no difference in pregnancy rates after superficial (33.3%) or deep and intrauterine (52.2%) IA, possibly due to the reduced number of animals used / O estresse oxidativo e a precoce capacitação espermática, gerados na criopreservação do sêmen ovino, reduzem sua viabilidade, principalmente na inseminação cervical. O uso de plasma seminal (PS) e a pressão negativa têm produzido a proteção e reversão desses danos. Dois experimentos avaliaram esses potenciais melhoradores da criotolerância, e um terceiro avaliou dois métodos de IA cervical. No experimento 1 o sêmen ovino foi submetido aos tratamentos: controle (TC), pressão de 200mBar (P200); 500mBar (P500) e 800mBar (P800). No experimento 2 o PS de carneiros, garanhões e touros foi liofilizado (L) e sua proteína dosada. De cada PS, o equivalente a 600&#956;g de proteína por mL, foi adicionado ao diluente de congelamento, compondo os grupos experimentais: controle (TC), PS ovino (PSLO), PS bovino (PSLB) e PS equino (PSLE). O experimento 3 avaliou 2 métodos de IA, a cervical superficial (G1) e a cervical profunda com pinçamento do fundo de saco vaginal (G2). Os dados in vitro foram submetidos a análise de variância e teste T, e a taxa de prenhez ao chi-quadrado, todos com significância de 5%. No experimento 1, maior motilidade progressiva (MP) foi observada no TC (49%) frente aos tratamentos P200 (40,9%), P500 (38,9%) e P800 (38,9%). Na MP durante o teste de termo resistência (TTR), MP após percoll (PP), integridade de acrossoma (IAC), IACPP, integridade de membrana (IM) e IMPP, não houve diferença entre os grupos. Na clivagem P800 (34,5%) foi inferior a P200 (51,2%) e P500 (50,9%), não diferindo do controle (44,3%). Conclui-se que a P500 é a mais adequada para uso com sêmen ovino, não reduzindo a viabilidade após o congelamento e proporcionando elevada taxa de clivagem após FIV heteróloga. O experimento 2 avaliou MP, MPPP e clivagem após FIV heteróloga de todos os grupos, sendo o melhor grupo comparado ao controle através de: sistema CASA, integridade de acrossoma (FITC-PSA), estabilidade de membrana (M540); integridade de cromatina (acridina orange); apoptose (anexina) e potencial de mitocôndria (mitotracker). O PSLE apresentou a maior taxa de clivagem (71,37%), evidenciando sua maior capacidade de penetração nos oócitos. Observou-se superioridade do PSLE nosparâmetros VCL (PC-163,5&#956;m/s, PSLE-186,2&#956;m/s) e ALH (PC-9&#956;m, PSLE- 8,2&#956;m) do CASA, em relação ao controle. Na citometria de fluxo, o teste da anexina revelou maior quantidade de células viáveis não apoptóticas com o PSLE (38,9%) em relação ao TC (32,1%). No experimento 3 não houve diferença na prenhez após IA superficial (33,3%) e profunda (G2 52,2%), possivelmente devido ao número reduzido de animais

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