In men with ART failure, sperm DNA sequencing ultrastructural analysis can identify specific defects and guide treatment. the past 2 years, 22 consenting who failed IVF cycles due to severe astheno-/teratozoospermia were recruited; specimens from 3 fertile used as controls. To assess ultrastructure by transmission electron microscopy (TEM), pelleted spermatozoa fixed, embedded, sectioned 100-nm...

background: the studies have indicated that inter marriage would increases the frequency of congenital disabilities compared with non-inter marriages. it seems that in our country inter marriage is one of the most important factors for disabilities in infants. this research was conducted to compare the relative frequency of congenital disabilities with type of marriage in jiroft city, which has...

Intracellular Ca(2+) oscillations at fertilization are responsible for triggering egg activation. The aim of this study was to examine the effect of the age of the oocyte donor and in-vitro maturation on the generation of Ca(2+) transients at fertilization. The results show that <10% of in-vivo and in-vitro matured oocytes from 19-day old mice develop to the blastocyst stage in vitro. In contra...

Cytokeratins have previously been shown to exist in the Xenopus oocyte cortex. Using three monoclonal antibodies against cytokeratins, we follow the appearance of cytokeratin-containing filaments, and their changes in distribution during oocyte differentiation and maturation. Cytokeratin-containing filaments are shown to change dramatically in distribution in the oocyte during its ontogeny.

Prediction and improvement of oocyte competence are two critical issues in assisted reproductive technology to improve infertility therapy. The lack of reliable and objective predictors of oocyte developmental competence for oocyte/embryo selection during in vitro fertilization hampers the effectiveness of this technology. Likewise, the low pregnancy rate resulting from in vitro maturation of h...

background: it is important to protect oocytes and embryos from oxidative stress in the culture medium. melatonin has been shown to be a direct free radical scavenger. objective: effect of melatonin during in vitro oocyte maturation, fertilization and embryo development of mouse oocytes was evaluated. materials and methods: oocytes from supper-ovulated mouse were divided to two groups: cumulus ...

In Drosophila, a single oocyte develops within a 16-cell germline cyst. Although all 16 cells initiate meiosis and undergo premeiotic S phase, only the oocyte retains its meiotic chromosome configuration and remains in the meiotic cycle. The other 15 cells in the cyst enter the endocycle and develop as polyploid nurse cells. A longstanding goal in the field has been to identify factors that are...

In the growing follicle, communication between the oocyte and its surrounding follicular cells is essential for normal oocyte and follicular development. Maturation of the fully grown oocyte in vivo is associated with the loss of cumulus cell-oocyte gap junctional communication, preventing entry of meiotic-modulating factors such as cAMP into the oocyte. We have previously shown that oocyte and...