objective: globozoospermia is a rare type of teratozoospermia with incidence of 0.1% among infertile individuals. phospholipase c zeta (plcζ) and postacrosomal sheath ww domain binding protein (pawp) are the main candidates in sperm taking responsibility for oocyte activation during fertilization. therefore, we aimed to evaluate the expression of these two genes at rna and protein levels in glo...

BACKGROUND Oocyte retrieval failure following an ovarian hyperstimulation protocol is uncommon in assisted reproductive technology (ART) programs. We analyzed the predictive factors for oocyte retrieval failure following controlled ovarian hyperstimulation (COH) with gonadotropin-releasing hormone (GnRH) agonist and GnRH antagonist protocols in ART programs. METHODS This study was a retrospec...

The molecular and structural changes in the follicle triggered by the gonadotropin luteinizing hormone (LH) at ovulation require complex interactions between somatic cells and the oocytes. It is well established that the signals originating from the oocytes play an essential role in orchestrating the growth and development of the follicle. Conversely, the exact contribution of local signals in ...

Fertilization in mammals is accompanied by Ca(2+) oscillations in the egg cytoplasm, leading to exit from meiosis and entry into the first embryonic cell cycle. The signal transduction pathway linking these Ca(2+) changes to cell-cycle related kinases has not yet been fully elucidated, but involves activation of calmodulin-dependent kinase II (CaMKII). Here, we develop a computational model to ...

Progesterone (P) is one of the physiological stimuli of human sperm acrosome reaction. It is present in high levels at the site of fertilization (cumulus oophorus) and has been describe to affect several sperm functions including motility, capacitation and acrosome reaction. The effects of the steroid, which is present in high levels in the cumulus matrix that surrounds the oocyte, are mediated...

With increasing medical utilization of assisted reproductive technology (ART), scientists and clinicians have been able to study extensively multiple cell functions operating synchronously and flawlessly during the events preceding, before and after fertilization. Critical evaluation of the functional status of spermatozoa for in vitro techniques such as sperm-mucus interaction, acrosome reacti...

Assisted reproductive technologies refer to procedures in which the oocyte is handled or manipulated in vitro before replacement, either as an oocyte or an embryo. Because of rapid advances in this area, infertile couples may seek direct referral for assisted reproductive treatments, instead of trying simpler measures such as ovulation induction and intrauterine insemination. It is important to...

Assisted reproduction is used to resolve infertility problems in human and in breeding programs to generate livestock. Except for gestation length and birth weight, perinatal outcome of children conceived by In Vitro Fertilization is similar to that of spontaneously conceived children. However, large offspring syndrome observed after In Vitro Production in livestock is quite alarming. The disti...