is believed to occur during the early stages of gamete fusion, and thus before the sperm tail is incorporated into the oocyte. Thus, our figure represents a specific temporal stage of fertilization and not the entire sequence of events. It would, therefore, be inaccurate and misleading to have shown the sperm tail incorporated into the oocyte at this stage. While we are content with the fact th...

Oocyte maturation is a key issue of current animal biotechnology. This study was designed to examine the morphodynamics of the cumulus-oocyte association during oocyte maturation. Porcine cumulus-oocyte complexes were recovered from slaughterhouse ovaries; matured in vitro for 0, 24, 36, and 44 h; and evaluated by scanning electron microscopy either combined or not combined with the osmium-dime...

background: in vitro maturation (ivm) is a promising treatment option for certain infertile women. nowadays, with the aid of polscope, it has become possible to evaluate zona pellucida (zp) characteristics as a parameter of oocyte quality. moreover, quality of oocytes can be influenced by many factors, such as patient’s age. the polscope system is a non-invasive technique to assess birefringent...

objective: the purpose of the present study was to verify the ultrastructural characteristics of cultured mouse preantral follicles from fresh and vitrified –warmed ovarian tissues. materials and methods: the ovaries of 14-day-old mice (n = 5) were vitrified using a mixture of ethylene glycol, ficoll 70 and sucrose. the preantral follicles were isolated and cultured in α-minimum essential mediu...

CONTEXT Our center's quality improvement optimization process on many occasions anecdotally suggested that oocyte assessments might enhance embryo assessment in predicting pregnancy chances with in vitro fertilization (IVF). OBJECTIVE To prospectively compare a morphologic oocyte grading system to standard day-3 morphologic embryo assessment. DESIGN, SETTING, PATIENTS We prospectively inves...

This paper reports a quick, relatively simple and reproducible technique for obtaining populations of zona fasciculata and zona glomerulosa cells up to 80-90% pure, which can be maintained in vitro for study of adrenocortical cell function. Isolated guinea pig adrenocortical cells were separated on a 1-28% bovine serum albumin/Ca++, Mg++-free buffer gradient (wt/vol at 4% increments) using equi...

Objective(s): The present day challenge is how to obtain germ cells from stem cells to treat patients with cancer and infertility. Much more efforts have been made to develop a procedure for attaining germ cells in vitro. Recently, human umbilical cord-derived mesenchymal stem cells (HUMSCs) have been introduced with higher efficacy for differentiation. In this work, we tried to explore the eff...

Background: The slow-freezing method is one of the most popular techniques to freeze human oocytes and it is also used in routine in vitro-fertilization (IVF) programs, particularly in those countries where embryo freezing is not allowed. Slow-freezing damages some of the structures of the egg, among which the meiotic spindle (MS) and the zona pellucida (ZP). Polarized Light Microscopy (PLM) pe...

background: para-nonylphenol (p-np) is one of the environmental pollutants which cause reproductive system disorders. objective: the effects of vitamin e on ovary structure during its development in rats treated with p-np. materials and methods: 32 wistar female rats after mating were divided into 4 groups; control vitamin e (100mg/kg/day) p-np (250mg/kg/day) and p-np + vitamin e. the rats were...