Global demethylation of DNA which marks the onset of development occurs asynchronously in the mouse; paternal DNA is demethylated at the the zygote stage, whereas maternal DNA is demethylated later in development. The biological function of such asymmetry and its underlying mechanisms are currently unknown. To test the hypothesis that the early demethylation of male DNA may be associated with p...

The endgame of Lines of Action (LOA) is problematic because (1) LOA evaluation functions are not good predictors in the case of forced wins and (2) the state-space complexity of the LOA endgame is too large to use endgame databases. Because of the frequency of forced moves and the mobility component in the LOA endgame the utility of proof-number (PN) search is investigated in this paper. Also t...

Non-Mendelian genes in Chamydomonas reinhardtii are inherited in a uniparental (UP) fashion. Most zygotes and their progeny receive UP genes only from the mt(+) or maternal parent. However, a few exceptional zygotes are also found in which the mt(-) or paternal UP genome is transmitted. Most of the exceptional zygotes are biparental in that their progeny segregate UP genes transmitted by both p...

Tripronuclear human zygotes were used to determine the feasibility of an enucleation procedure without the use of cytoskeleton inhibitors to obtain intact cytoplasts for nuclear transfer research. Of 61 tripronuclear human zygotes manipulated, 100% of the zygotes survived after removal of one pronucleus and 90.1% after complete enucleation, proving the reliability of the proposed microsurgical ...

This study was undertaken to compare the efficiency of fresh and frozen-thawed buck semen on in vitro fertilization (IVF) of goat oocytes. Cumulus oocytes complexes (COCs) were collected by aspiration of 2-6 mm diameter follicles, which were obtained from slaughterhouse. Upon grading, only normal quality COCs were maturated in TCM-199 for 48 hours. The percentage of COCs reached to the M-II sta...

Mutant mice are indispensable to biological and medical research, and transgenic mouse production by DNA injection into zygotes has been an important method for producing these mice which are used to examine the over-expression of genes and to analyze gene transcriptional regulatory sequences. Recently, cryopreservation of zygotes by a simple vitrification method has become popular, saving the ...

The reproduction, or duplication, of the centrosome is an important event in a cell's preparation for mitosis. We sought to determine if centrosome reproduction is regulated by the synthesis and accumulation of cyclin proteins and/or the synthesis of centrosome-specific proteins at each cell cycle. We continuously treat sea urchin eggs, starting before fertilization, with a combination of emeti...

The aim of the present study was to investigate the effects of centrifugation pretreatment on the viability and nuclear status of porcine in vitro matured (IVM) oocytes and on the developmental competence of in vitro fertilized (IVF) oocytes (zygotes) after cryopreservation by vitrification (Solid Surface Vitrification; SSV). Mature oocytes having the first polar body after IVM and zygotes havi...

Recently, there is a need for fostering the critical reflective side of L2 teacher education. This study investigated the implications of personal narrative (PN) and reflective journal (RJ) writing for Iranian EFL teachers’ reflective writing. Sixty (36 women and 24 men) in-service secondary school EFL teachers were selected based on the convenience sampling from Iran. L2 teachers equally divid...