This study examined the effects of human menopausal gonadotrophin (HMG) or human chorionic gonadotrophin (HCG) priming on cumulus-oocyte complex (COC) morphology, oocyte maturation and embryo development in patients undergoing in-vitro maturation (IVM) cycles. The patients were primed with nothing (group 1), low-dose HMG (group 2) or 10,000 IU HCG (group 3) before oocyte retrieval. COC with dis...

cussed and compared. Spontaneous oocyte nuclear maturation occurs when large ovarian follicles are isolated into seawater and this process is sensitive to the calcium and hydrogen ion concentrations in seawater. In the presence of calcium ions induction of spontaneous oocyte maturation is closely associated with loss of follicle cells from the oocyte. In the absence of calcium ions, follicle ce...

introduction: superovulation produces complications in some patients, so invitro maturation of oocytes is used to decrease or eliminate these complications and improve ivf. moreover, ivm is used for different aspects of reproductive researches. slaughterhouse ovaries are the main source of oocytes for ivm and ivf studies. different media has been introduced and experimented for in vitro maturat...

4 Introduction 4 A. Zebrafish as a Model Organism for Developmental Biology 4 B. Processes of Oocyte Maturation in Zebrafish 5 C. Wnt Signaling Pathways and Their Possible Role in Oocyte Maturation 11 D. Preliminary Findings and Objectives of This Research Project 15 Materials and Methods 16 A. Overview 16 B. Oocyte Harvesting and in vitro Maturation 17 C. RNA Extraction and cDNA Conversion 18 ...

In sexually reproducing animals, the ability to coordinate oocyte maturation and sperm availability has profound effects on reproductive success. InCaenorhabditis elegans, cell–cell signaling is crucial for promoting germline development, oocyte maturation, and ovulation. In this issue of Genes & Development, Miller et al. (2003) provide new insights into the role that sperm play in oocyte matu...

In the process of oocyte maturation, gonadotrophins are believed as main stimulators for oocyte meiosis resumption. However, which gonadotrophin (i.e. FSH or LH) is the key hormone in this process is still unknown. This study indicated a close relationship between LH and FSH on activating meiotic maturation of oocyte in vitro. FSH efficiently induced oocyte meiosis at concentration of 50 IU/L, ...

Maternal factors are required for oocyte maturation and embryo development. To better understand the role of DNA methyltransferase 1 (Dnmt1) in oocyte maturation and embryo development, small interfering RNA (siRNA) was conducted in porcine oocytes. In this study, our results showed that Dnmt1 localized in oocyte cytoplasm and its expression displayed no obvious change during oocyte maturation....

Oocyte maturation depends on multiple variables. In fact, in dogs, the requirements for oocyte development in vitro are so complex that achievement of female gamete maturation has been viewed as a difficult problem. The conundrum, thus far unanswered, of achieving dog oocyte maturation in vitro, is nowadays the major puzzle of the in vitro program in the canine species. In in vitro studies of d...

In fish, oocyte meiotic maturation is regulated by 17α, 20β-dihydroxy-progesterone through cAMP. To study the role of cAMP response element binding protein (CREB) in meiotic maturation, we cloned and characterized the expression pattern of CREBs from two fish models, the Nile tilapia and catfish. In the Nile tilapia three different CREBs were identified where in CREB1 was found in many tissues ...

We analyzed the expression of mRNAs for growth factor [epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (bFGF) and platelet-derived growth factor A chain (PDGF-A)] and their receptor (R) by reverse transcription-polymerase chain reaction in bovine ova during oocyte maturation in vitro (0-21 hr) and after fertilization in vitro (6-144 hr: zygote...