Background Polycystic ovary syndrome (PCOS) is one of the reasons of infertility in women with chronic anovulation. Ovulation process is tightly regulated by molecular mechanisms controlling proliferation/differentiation of cells. Telomeres, TTAGGG tandem repeats, are transcribed into a non coding RNA, named TERRA. Recent studies suggest that TERRA sustain several important functions at chromos...

BACKGROUND Oocytes are the female gametes which establish the program of life after fertilization. Interactions between oocyte and the surrounding cumulus cells at germinal vesicle (GV) stage are considered essential for proper maturation or 'programming' of oocytes, which is crucial for normal fertilization and embryonic development. However, despite its importance, little is known about the m...

BACKGROUND Gene expression of cumulus cells (CC) could predict oocyte developmental quality. Knowledge of the genes involved in determining oocyte quality is scanty. The aim was to correlate clinical and biological characteristics during ovarian stimulation with the expression of 10 selected genes in CC. METHODS Sixty-three ICSI patients were stimulated with GnRH-agonist plus highly purified ...

This paper postulates that in the ovary, the close association between the cumulus cells and the oocytes permits the fertilizing ability of the oocytes to be determined indirectly through cumulus cell DNA status. The objective was to use a modified comet assay to analyse cumulus cell DNA and relate the data to oocyte fertilization after intracytoplasmic sperm injection (ICSI) procedures. Oocyte...

Ovulation is the complex, inflammatory-like process by which the cumulus oocyte complex (COC) is released from a mature, preovulatory follicle through a rupture site at the ovarian surface and requires expression of genes that generate and stabilize the expanded extracellular COC matrix. Gene profiling analyses of COCs at selected time intervals during ovulation revealed that many genes associa...

CD44 is a polymorphic and polyfunctional transmembrane glycoprotein widely expressed in many types of cells. Here, the expression of this protein on human membrana granulosa was studied by two techniques. Using confocal laser scanning microscopy (CLSM) with the mouse monoclonal antibody to human CD44 (clone G44-26), cells immunoreactive for CD44 were observed in both cumulus and mural granulosa...

Background An evaluation of the developmental competence of vitrified mouse germinal vesicle (GV) oocytes with various equilibration and vitrification times; in the presence or absence of cumulus cells and by comparison between the cryotop method and straws was performed. MaterialsAndMethods Mouse GV oocytes were considered in cumulus-denuded oocytes (CDOs) and cumulus-oocyte complexes (COCs) g...

In human IVF procedures objective and reliable biomarkers of oocyte and embryo quality are needed in order to increase the use of single embryo transfer (SET) and thus prevent multiple pregnancies. During folliculogenesis there is an intense bi-directional communication between oocyte and follicular cells. For this reason gene expression profile of follicular cells could be an important indicat...

A search for genes expressed more highly in mouse cumulus cells than mural granulosa cells by subtraction hybridization yielded Slc38a3. SLC38A3 is a sodium-coupled neutral amino acid transporter having substrate preference for l-glutamate, l-histidine, and l-alanine. Detectable levels of Slc38a3 mRNA were found by in situ hybridization in granulosa cells of large preantral follicles, but level...

The perivitelline space is the gap between the plasma membrane and the zona pellucida of the oocyte. Although not present in the oocytes in the germinal vesicle stage, the perivitelline space is known to start forming when meiotic maturation resumes and to enlarge in matured oocytes at the metaphase II stage (Kaufman et al., 1989; Okada et al., 1993). Recently, it has been suggested that there ...