BACKGROUND Although unsaturated fatty acids such as eicosapentaenoic acid (EPA, C20:5n-3), docosahexaenoic acid (DHA, C22:6n-3) and arachidonic acid (ARA, C20:4n-6), collectively known as the highly unsaturated fatty acids (HUFA), play pivotal roles in vertebrate reproduction, very little is known about their synthesis in the ovary. The zebrafish (Danio rerio) display capability to synthesize a...

Experimental immune ovarian failure induced in CBA mice by either administration of xenogenic anti-ovarian antibodies or immunization with allogenic ovarian extracts impaired the meiotic maturation of oocytes and increased apoptosis of follicular cells. Immunization was accompanied with the inflammation and active immune reaction, as shown by the enlargement of regional lymph nodes, the increas...

The ultrastructural analysis of oocytes and ovarian follicles has been used to evaluate the effects of assisted reproductive techniques, such as cryopreservation or in vitro oocyte maturation. It also benefits the understanding of such complex mechanisms that occur during folliculogenesis. From the beginning of primordial follicles growth until oocyte maturation in preovulatory follicles oocyte...

Xenopus laevis has been used for many decades to study oocyte development and maturation. The Xenopus oocytes' large size, relative abundance, and clearly defined progression of physical characteristics from oogonia to eggs make them ideal for studying oogenesis. In addition, the ability of steroids to trigger Xenopus oocyte maturation in vitro has resulted in their extensive use for the study ...

Background: Mammalian oocyte undergoes a series of structural nuclear modulations during maturation in order to obtain full competence to support fertilization and early embryonic development. Microtubules are major cytoskeleton components and have pivotal modulators for chromosomal movement, and it has been shown that partial or immature spindle organization may compromise correct ploidy of th...

Two decades ago, the diagnosis of premature sexual development was considered to be simple; the conditions that were recognised were either central precocious puberty, isolated premature thelarche or an adrenal aetiology. The use of pelvic ultrasound and gonadotrophin-releasing hormone (GnRH) analogue treatment was to completely alter our understanding of these disorders. Pelvic ultrasound led ...

Maturation arrest of human oocytes may occur at various stages of the cell cycle. A total failure of human oocytes to complete meiosis is rarely observed during assisted conception cycles. We describe here a case series of infertile couples for whom all oocytes repeatedly failed to mature during IVF/ICSI. Eight couples, all presenting with unexplained infertility, underwent controlled ovarian s...

In-vitro fertilization (IVF) relies heavily on controlled ovarian stimulation to increase the number of available oocytes and embryos, and therefore the pregnancy rate. However, the side effects, such as nausea, mood swings, menopausal symptoms, ovarian hyperstimulation syndrome (OHSS), and potential cancer risk of ovarian stimulation may not be avoided. Therefore, the recovery of immature oocy...

In newborn mammals, most of the germ cell population rests in a pool of quiescent small follicles in the ovaries. Regularly throughout adulthood, a small percentage of these oocytes and follicles grows to a certain stage of development and then either degenerates or matures and ovulates. This entire process is under both exogenous and endogenous control. Recent work, including my laboratory's, ...

to investigate the effects of different hormonal treatments on the oocyte maturation in wild- caught grey mullet ( mugil cephalus ), fish were subjected to 4 different hormonal treatments as follows: (a) a control group received 0.5 ml/kg b.w. physiological saline, (b) fish injected with 20 mg/kg carp pituitary extract (cpe) as a priming dose followed by 200 µg/kg sgnrha as resolving dose, (c) ...