Background: The beneficial effect of supplementing culture medium with melatonin has been reported during in vitro embryo development of species such as mouse, bovine and porcine. However, the effect of melatonin on the mouse somatic cell nuclear transfer remained unknown. Materials and Methods: In this study, we assessed the effects of various concentrations of melatonin (10-6 to 10-12 M) on t...

LKB1/PAR-4 is essential for the earliest polarization steps in Caenorhabditis elegans embryos and Drosophila oocytes. Although LKB1 (also known as STK11) is sufficient to initiate polarity in a single mammalian intestinal epithelial cell, its necessity in the formation and maintenance of mammalian epithelia remains unclear. To address this, we completely remove LKB1 from mouse embryos by genera...

This study was aimed at evaluating the effects of multi-layered cumulus cells (MCCs) during vitrification and in vitro fertilization (IVF) of mature bovine oocytes and embryogenesis after IVF. The rates of cleavage and blastocyst formation were higher in vitrified and fertilized oocytes with MCCs than in denuded oocytes (P < 0.05), but were comparable to the rates in fresh oocytes with MCCs or ...

Background: The growth factors that drive the division and differentiation of stem cells during early human embryogenesis are unknown. The secretion of endorphins, progesterone (P(4)), human chorionic gonadotropin, 17beta-estradiol, and gonadotropin-releasing hormone by trophoblasts that lie adjacent to the embryoblast in the blastocyst suggests that these pregnancy-associated factors may direc...

OBJECTIVE To evaluate the developmental competence and chromosomal normality of oocytes vitrified at various times after maturation culture. DESIGN In vitro model study. SETTING A university-affiliated hospital. PATIENT(S) Unstimulated women who underwent cesarean section or oophorectomy and infertile women who underwent a long protocol of GnRH stimulation. INTERVENTION(S) Retrieved ooc...

Transgenic porcine induced pluripotent stem (iPS) cells are attractive cell sources for the development of genetically engineered pig models, because they can be expanded without senescence and have the potential for multiple gene manipulation. They are also useful cell sources for disease modeling and treatment. However, the generation of transgenic porcine iPS cells is rare, and their embryon...

BACKGROUND Since there is considerable disagreement in grading cytoplasmic haloes, this prospective study was set up to evaluate if certain subtypes of haloes are related to further development. METHODS Out of a total of 152 patients, 713 zygotes could be checked for the formation of a halo. Where present, haloes were subdivided into concentric (symmetric) and polar (asymmetric) types. In add...

Increases in Na/K-ATPase activity occur concurrently with the onset of cavitation and are associated with increases in Na(+)-pump subunit mRNA and protein expression. We have hypothesized that the alpha1-isozyme of the Na/K-ATPase is required to mediate blastocyst formation. We have tested this hypothesis by characterizing preimplantation development in mice with a targeted disruption of the Na...