Gonadotropins were used to stimulate luteal function, as determined by progesterone secretion, in both in vitro and in vivo systems. LH and hCG were capable of significantly stimulating progesterone secretion in the in vivo systems. Stimulation of progesterone secretion by hCG was greater than that for LH. PMSG failed to increase progesterone production at any level of treatment. hCG was also used to stimulate progesterone production by the corpus luteum in mares during early gestation. hCG administration resulted in a significant (p < 0.10) increase in peripheral progesterone levels in treatment mares through day 14 post-estrus. Peripheral progesterone concentrations were also higher in hCG treated mares for days 15 through 30 post-estrus in mares that conceived. hCG treatment had no influence on anterior pituitary release of LH.

Acquisition of full developmental competence of oocytes not only occurs during growth stage, and the final preparation during oocyte maturation is also critical. Previous studies have shown that nuclear maturation can occur spontaneously following culture in vitro; however, there may be some insufficiency in cytoplasmic maturation of the in vitro matured oocytes. But till now, the differences of the events of cytoplasmic maturation between in vitro and in vivo matured oocytes are still not clear. Ovarian stimulation by gonadotrophins is used to permits the growth and development of follicles, to time the initiation of pre-ovulatory oocyte maturation, and to increase the numbers of oocytes ovulated. It is one of the foundations of current treatments of human infertility. The success of clinical IVF has been depending on generation of matured oocytes at high frequency. However, ovarian stimulation with gonadotropins is associated with side effects and complications. / In order to illuminate mechanisms which affect the developmental competence of oocytes produced in vitro, in the present study, we have compared the difference of the quality of oocytes produced in vitro with that of the oocytes produced in vivo using mouse model. In order to understand the relationship between oocyte competence and ovarian responses to stimulation in the mouse, we also have compared difference of the quality of oocytes produced in vitro or in vivo from gonadotrophns stimulated ovaries with that of from natural cycling ovaries. / In-vitro matured oocytes were collected from (1) naturally ovulated mice and (2) superovulated (PMSG + hCG) mice. Immature oocytes were retrieved from (3) naturally cycling mice, and (4) from mice primed with PMSG. The results indicate that the percentages of cleavage and blastocyst formation are significantly different (P&lt;0.05) between in-vivo and in-vitro matured oocytes. Blastocyst formation rate is significantly higher (P&lt;0.05) in immature oocytes derived from PMSG primed mice compared to immature oocytes derived from naturally cycling mice. The percentages of oocytes with comet tails and the length of comet tails are significantly higher and longer respectively in in-vitro matured oocytes compared to in-vivo matured oocytes. Total cell numbers of blastocyst are also significantly different (P&lt;0.05) between in-vivo and in-vitro matured oocytes. However, there are no differences in ratio of trophectoderm (TE)/inner cell mass (ICM) between in-vivo and in-vitro matured oocytes. In conclusion, in-vivo matured mouse oocytes are more competent than those of matured in-vitro, suggesting that it may be due to its less damage of DNA. Embryonic development capacity of in-vivo matured oocytes is not promoted by ovarian stimulation. Gonadotropin priming prior to immature mouse oocyte retrieval is beneficial to subsequent embryonic development. / Keywords. mouse oocyte, IVM, IVF, gonadotropin, development

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on March 25, 2010). Vita. Thesis advisor: Michael Roberts. "December 2009" Includes bibliographical references

Graphene is essentially a monolayer of sp2 bonded carbon atoms, arranged in a honeycomb lattice. Graphene has in recent years attracted phenomenal interest from researchers in materials science, condensed matter physics, and electronics since its first demonstration in 2004. The importance of graphene research was epitomised by the Nobel prize for physics being awarded to pioneers of the field in 2010. The main topic of this research was the development of epitaxial graphene on silicon carbide (SiC) substrates. The substrate inferred processability of epitaxial graphene enables graphene devices to be fabricated on full wafers using standard semiconductor processing techniques. Biosensor research is a rapidly expanding field. The major driver comes from the healthcare industry but there are also applications for biosensors in the food quality appraisal and environmental monitoring industries. The key advantages of electrochemical biosensors over competing sensor technologies are the low cost of mass production, and ability to make sensors into small compact systems. Smaller, portable sensors allow for the development of point-ofcare medical devices, which can be crucial in fast diagnosis and long-term monitoring of diseases. Graphene channel resistor devices have been fabricated using electron beam lithography and a successfully developed contact metallisation scheme - using Titanium / Gold contacts. The metal-graphene contacts have been characterised using XPS and electrical current-voltage measurements. The graphene channel device has been used as the basis of an electrochemical sensor for human chorionic gonadotropin (hCG), an indicator of pregnancy - which has also been linked to increased risk of several cancers. The immunosensor developed is a promising tool for point-of-care detection of hCG, due to its excellent detection capability, simplicity of fabrication, low-cost, high sensitivity and selectivity.

Made available in DSpace on 2014-10-09T12:53:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:22Z (GMT). No. of bitstreams: 1 12446.pdf: 3602261 bytes, checksum: 6845356e112313cd1d8624dcc0ef1554 (MD5) / Tese (Doutoramento) / IEA/T / Instituto de Biociencias, Universidade de Sao Paulo - IB/USP

Orientador: Wilter Ricardo Russiano Vicente / Coorientador: Márcia Rita Fernandes Machado / Banca: Leandro Zuccolotto Crivellenti / Banca: Eliandra Antônia Pires Buttler / Banca: Maricy Apparício Ferreira / Resumo: Nos últimos anos, com a escassez de alimentos, o ser humano vem buscando alternativas de possíveis fontes de proteínas para a sua nutrição. A criação de pacas em cativeiro pode ser uma opção viável desde que explorada adequadamente. Fatos como esse favorecem o desenvolvimento de pesquisas científicas relacionadas à biotecnologia da reprodução, onde essas deixam de ser realizadas unicamente devido a uma preocupação com a conservação da espécie, mas também como uma forma de melhorar a sua produção zootécnica. Com a escassez de dados na literatura surgem dúvidas se seria possível obter oócitos viáveis de pacas para maturação in vitro (MIV). Dessa forma, objetivou-se com esse estudo estabelecer técnica viável de aspiração folicular em pacas, testando efeitos de protocolos hormonais sobre taxa de recuperação de oócitos e MIV, além de avaliar os procedimentos cirúrgicos e os aspectos reprodutivos. Para isso oito fêmeas adultas foram submetidas a quatro tratamentos cada, para a coleta de oócitos por meio de aspirações foliculares auxiliada por videolaparoscopia, onde em três desses tratamentos, houve estímulos hormonais utilizando eCG e FSH. Oócitos recuperados em cada tratamento foram classificados qualitativamente e em seguida submetidos à MIV. Posteriormente, os mesmos foram avaliados quanto ao estado de maturação nuclear. Após todas as análises, conclui-se que a administrações de gonadotrofinas não foram eficientes para superestimular os grupos tratados ou aumentar a eficiência ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In recent years, with food shortages, the being human has been seeking possible alternative sources of protein for nutrition. Breeding of spotted pacas in captivity would be one of those alternatives, if exploited properly. Facts as that favor the development of scientific research related to biotechnology of reproduction, where these are no longer held solely because of a concern for conservation of this species, but also as a way to improve their zootechnical production. Due to lack of data in the literature doubts arise whether it would be possible to obtain viable oocytes from spotted pacas for in vitro maturation. Thus, the aim of this study was to establish viable technique of ovum pick-up in spotted pacas, testing effects of hormonal protocols on recovery rate of oocyte and IVM, and to evaluate the surgical and reproductive aspects. For this eight adult females were subjected to four treatments each, to collect oocytes by laparocoic ovum pick-up, which in three of these treatments were used hormonal stimulation with eCG and FSH. Retrieved oocytes in each treatment were classified qualitatively and then submitted to IVM. Subsequently, they were evaluated for nuclear maturation. After all analyzes, we conclude that the gonadotropin treatments were not efficient to hyperstimulate the treated groups or increased the oocyte recovery efficiency. Thus, further studies are needed, especially for new protocols, such as higher doses or frequency of administration as well as accu... (Complete abstract click electronic access below) / Doutor

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No description available.

Purpose - The purpose of the present study is to compare intrauterine msemination (IUI) pregnancy rates (PR) as a function of diagnosis and ovulation protocol utilizing an extended semen transport time. This allowed clients to conveniently collect IUI specimens in the comfort and privacy of their home. A single IUI per treatment cycle was performed. Basic Procedures - Three-hundred-ten consecutive infertilty couples having unexplained, male factor, ovulatory dysfunction, endometriosis, tubal factor or combined diagnostic factors receiving a total of 584 cycles of IUI were included. Ovulation protocols included LH surge, clomiphene citrate (CC)-hCG, CC-gonadotropins(Gn)-hCG, Gn-hCG or leuprolide acetate (L)-Gn-hCG followed 36-42 hours by a single IUI. Pregnancy rates per cycle (fecundity) and per couple (fertility) as a function of diagnosis, ovulation protocol and cycle number were evaluated. In each cycle the couples processed the specimen by adding sperm washing medium at room temperature to the specimen 30 min following collection and allowed it to incubate for two hours prior to IUI during transport. Main Findings - Overall, fecundity was 11.8% (69/584) and fertility was 22.3% (69/310); respectively by diagnosis was: unexplained 22.6%,38.8%; male factor 18.8%,42.9%; ovulatory dysfunction 12.4,22.6%; endometriosis 5.3%,11.1%; tubal factor 7.6%,13.3%; and combined factors 9.7%, 20.0%. Unexplained vs endometriosis (P < 0.0001, P < 0.005), tubal factor (fecundity P < 0.008) and ovulatory dysfunction (fecundity P < 0.027) was statistically different. Male factor vs endometriosis (P < 0.011, P < 0.036) was significantly different. Ovulatory dysfunction vs endometriosis was significantly different (fecundity P < 0.027). Pregnancies by ovulation protocol: LH surge 4.5%,10.5%; CC-hCG 9.4%,14.9%; CC-Gn-hCG 13.7%,23.7%; Gn-hCG 17.5%,45.3%; L-Gn-hCG 3.5%,6.7%. For Gn-hCG vs L-Gn-hCG (P < 0.009, P < 0.030) and LH surge (fecundity P < 0.033). CC-Gn-hCG vs CC-hCG (fertility P < 0.050) and L-Gn-hCG (P < 0.033, P < 0.034). Gn-hCG vs CC-hCG (fecundity P < 0.043). Conclusions - We conclude that IUI is effective when utilizing an extended transport time allowing most couples to collect the specimen at home and is most effective when utilizing Gn-hCG therapy. Based on our analysis, endometriosis, tubal factor and combined diagnostic categories should proceed earlier to higher level assisted reproductive technologies.