Background: The cryopreservation of immature oocytes at the germinal vesicle (GV) stage would create an easily accessible, nonseasonal source of female gametes for research and reproduction. The present study investigated the ability of ovine oocytes vitrified at the GV stage using a cryoloop to be subsequently matured, fertilized and cultured in vitro to blastocyst-stage embryos. Materials and...

BACKGROUND Some reports show that it is possible to isolate immature oocytes from human ovarian tissue retrieved by a cortex biopsy or ovariectomy of non-stimulated ovaries and mature them in vitro. The mature oocytes can be vitrified and stored for in vitro fertilization, which, along with ovarian tissue cryopreservation, is mostly practiced in young cancer patients to preserve their fertility...

Oocyte developmental competence is one of the determining factors that in?uence outcomes an IVF cycle regarding ability a female gamete to reach maturation and be fertilized. A non-invasive approach using proteomic analysis oocyte cumulus cells (CCs) can used as method predict viability could potentially function molecular predictors for program prognosis. Our study was aimed at quantifying pro...

One of the first events that occurs at fertilization is a transient modification of the electrical properties of the oocyte plasma membrane. The whole-cell voltage clamp technique was used to demonstrate an outward ion current and a hyperpolarization of the plasma membrane after fertilization in bovine oocytes. These electrical events, together with measurement of internal calcium concentration...

Zona-free oocytes of the mouse were inseminated at prometaphase I or metaphase I of meiotic maturation in vitro, and the behavior of the sperm nuclei within the oocyte cytoplasm was examined. If the oocytes were penetrated by up to three sperm, maturation continued during subsequent incubation and became arrested at metaphase II. Meanwhile, each sperm nucleus underwent the following changes. Fi...

Abstract Background The gene expression of anti-Mullerian hormone receptor type 2 ( AMHR2 ) and follicle stimulating (FSHR) in cumulus cells (CCs) isolated from mature immature oocytes was studied as a possible non-invasive approach for determining oocyte maturity quality. CCs 100 infertile women with different etiologic factors were subdivided into control (CCs MII) case GV) group. Q-PCR used ...

The aim of this study was to evaluate the suitability of a commercial kit for bovine embryo vitrification for cryopreserving cat oocytes and to evaluate comparatively the effects of its use with slow freezing procedure on cryotolerance in terms of morphology and oocyte resumption of meiosis. Germinal vesicle stage oocytes isolated from cat ovaries were either vitrified (n = 72) using a vitrific...