Publications by authors named "Livia A Lisboa"

Folliculogenesis is a process of development and maturation of the ovarian follicles, being essential for the maintenance of fertility. In in vivo conditions, 99.9% of the follicles of an ovary do not ovulate and undergo atresia.

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The objective of this study was to evaluate the effects of adding ascorbic acid to the media for in vitro culture of cattle ovarian fragments and to determine their effects on growth activation and viability of early-stage follicles. The ovarian cortex was divided into small fragments; one fragment was immediately fixed (control) and the other fragments were cultured in minimum essential medium (MEM) supplemented or not with various doses of ascorbic acid. Ovarian tissue was processed for histology, transmission electron microscopy (TEM) and immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA).

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Dynamic changes in chromatin structure and gene expression occur during follicular and oocyte growth. Epigenetic mechanisms regulate these changes through biochemical reactions that modify the nucleosome structure, and consequently affect transcription. Chromatin remodellers that alter DNA-histone interactions can influence transcriptional activity by facilitating or repressing DNA access.

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