65 resultados para STERILITY
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Morphological caste differences and ovary conditions were analyzed in four colonies of Brachygastra augusti collected in different stages of the colony cycle. Differences between castes are distinct suggesting pre-imaginal determination. Many intermediates (non-inseminated ovary-developed females) were found. Because these intermediate females were morphologically similar to workers, it is suggested that they are young ovary-developed workers. Because there is a more evident overlap between queens and workers in the colony in pre-emergence of workers stage, and in three colonies in latter stages, especially in worker-production colonies, it is suggested that smaller queens are probably less viable than larger queens as observed in previously studied epiponines.
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Frieseomelitta varia worker bees do not lay eggs even when living in queenless colonies, a condition that favors ovary development and oviposition in the majority of highly social bees. The permanent sterility of these worker bees was initially attributed to a failure in ovary morphogenesis and differentiation. Using transmission electron microscopy we found that at the beginning of the pupal phase the ovaries of F. varia workers are formed by four ovarioles, each of them composed of 1) a terminal filament at the apex of the ovarioles, containing juxtaposed and irregularly shaped cells, 2) a germarium with clusters of cystocytes and prefollicular cells showing long cytoplasmic projections that envelop the cystocyte clusters, 3) fusiform interfollicular and basal stalk precursor cells, and 4) globular, irregularly contoured basal cells with large nuclei. However, during the pupal phase an accentuated and progressive process of cell death takes place in the ovarioles. The dying cells are characterized by large membrane bodies, electron-dense apoptotic bodies, vacuoles, vesiculation, secondary lysosomes, enlarged rough endoplasmic reticulum cisternae, swollen mitochondria, pycnotic nuclei, masses of chromatin adjacent to the convoluted nuclear envelope, and nucleoli showing signs of fragmentation. Cell death continues in ovarioles even after the emergence of the workers. Once they become nurse bees, the ovaries have become transformed into a cell mass in which structurally organized ovarioles can no longer be identified. In F. varia workers, ovariole cell death most certainly is part of the program of caste differentiation.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Regression analysis of 538 semen samples demonstrated that percentages of normal nuclear sperm and all spermatozoa with abnormalities of nuclear form at high magnification had significant negative correlation with percentages of DNA fragmentation. on the other hand, there was a positive correlation between percentages of spermatozoa with nuclear vacuoles and those with DNA fragmentation. (Fertil Steril (R) 2010;94:1937-40. (C) 2010 by American Society for Reproductive Medicine.)
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The comparison between the outcomes of intracytoplasmic morphologically selected sperm injection performed in couples with male factor infertility according to the World Health Organization guidelines from 1999 and 2010 was the objective of this study. Our results suggest that the sperm selection under high magnification results in improved treatment outcomes in patients with oligoasthenoteratozoospermia, according to the new World Health Organization guidelines. (Fertil Steril (R) 2011;95:2711-4. (C)2011 by American Society for Reproductive Medicine.)
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Objective: To evaluate the effect of artificial oocyte activation (AOA) on intracytoplasmic sperm injection (ICSI) cycles using surgically retrieved sperm.Design: Laboratory study.Setting: Fertility/assisted fertilization center.Patient(s): Couples undergoing surgical sperm retrieval for ICSI (n = 204).Intervention(s): Application of calcium ionophore A23187 for AOA.Main Outcome Measure(s): Cycles were divided into experimental groups according to the origin of the sperm used for injection and the type of azoospermia: [1] testicular sperm aspiration in nonobstructive-azoospermic patients (TESA-NOA group, n = 58), [2] TESA in obstructive-azoospermic patients (TESA-OA group, n = 48), [3] and percutaneous epididymal sperm aspiration in obstructive-azoospermic patients (PESA-OA, n = 98). For each experimental group, cycles where AOA was applied (subgroup: activation) were compared with cycles in which AOA was not applied (Subgroup: control). The fertilization, high-quality embryo, implantation, and pregnancy rates were compared among the subgroups.Result(s): For patients undergoing TESA, AOA did not improve ICSI outcomes for either type of azoospermia. However, for cases in which the injected sperm were retrieved from the epididymis, a statistically significantly increased rate of high-quality embryos was observed with AOA.Conclusion(s): Artificial oocyte activation may improve ICSI outcomes in azoospermic patients when epididymal, but not testicular spermatozoa, are injected. (Fertil Steril (R) 2009;92:131-6. (C)2009 by American Society for Reproductive Medicine.)
SEMEN ANALYSIS BY MOTILE SPERM ORGANELLE MORPHOLOGY EXAMINATION (MSOME) IN INFERTILE and FERTILE MEN
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Objective: To describe the prevalence of hysteroscopic findings and histologic diagnoses inpatients with abnormal uterine bleeding (AUB).Design: Retrospective series of consecutive patients.Setting: Tertiary care University hospital and private office.Patient(s): Four thousand fifty-four hysteroscopies with biopsy in patients with AUB evaluated between June 1993 and December 2004.Intervention(S): Hysteroscopies were performed using 2.9-mm or 4-mm telescopes with CO2 or saline as the distension media. Biopsies were (lone with a 5-mm grasper or with a Novak's curette.Main Outcome Measure(s): Prevalence of hysteroscopic findings and histologic analysis of biopsies.Result(S): Endometrial polyp was the most frequent hysteroscopic finding, accounting for 1,374 (33.9%) cases. Normal uterine cavity and cervical canal were found in 814 (20.1%) patients. Submucous fibroids were diagnosed in 302 (7.5%) women. Normal endometrium was the most frequent histologic diagnosis, accounting for 1,888 (46.6%) cases. Endometrial polyp was found in 1, 115 (27.5%) patients. Endometrial hyperplasia was diagnosed in 613 (15.1%) and endometrial cancer in 105 (2.6%) women.Conclusion(s): Endometrial polyps are the most frequent hysteroscopic findings in patients with AUB, whereas normal endometrium is the most frequent histologic diagnosis.