BACKGROUND Digynic zygotes with three pronuclei and one polar body obtained after intracytoplasmic sperm injection (ICSI) were studied cytogenetically to elucidate the frequency and origin of chromosomal abnormalities at the earliest stage of conception. METHODS Uncleaved, single-cell zygotes were incubated with podophyllotoxin and vinblastine and fixed by a gradual fixation air drying method...

background: the basal medium that supports isolated mouse oviduct (imo) is important for supporting embryo development and quality. methods: the culture of ovine ivm/ivf zygotes was done in imo using sofaacibsa and sofaabsa as basal medium of imo and in sofaabsa alone as control. for preparation of imo mature inbred strain c57bl/6 female mice were synchronized and mated with vasectomized males....

The present study was conducted to examine the development of nucLear transplant embryos produced by transplanting nucLei to either oocytes or zygotes in the mouse. Metaphase II oocytes and one-cell zygotes were enucleated and fused with transferred nuclei from late two-, fourand eight-cell stage embryos. Enucleation of metaphase oocytes was achieved using the interference microscope without st...

The present work describes analysis of the growth hormone gene (GH) expression in non-matured and in vitro matured bovine oocytes as well as zygotes after in vitro fertilization. The Leu/Val polymorphism described in the 5th exon of the bovine GH gene was applied to investigate the expression of genetic variants in the analyzed material. Experiments were performed on oocytes collected from hete...

In zygotes, DNA damage delays the first cleavage to enable repair. Our previous study found that 0.03 mM hydrogen peroxide (H2O2) was the minimum concentration required for induction of oxidative DNA damage in mouse zygotes and that this represented the most similar situation to the clinical phenomenon. In this study, we quantified the cleavage rates of cells in blastocysts at different develop...

Transgenic mammals, from small laboratory rodents to domestic animals, have been successfully produced to date, but their production efficiency within or across species has been variable. This is probably due to the differences in the type of injected DNA and/or technical procedures employed in each laboratory, as well as the reproductive characteristics of the species. Here we report the direc...

OBJECTIVE It has previously been suggested that embryos developing from intracytoplasmic sperm-injected (ICSI) zygotes with three pronuclei (3PN) are endowed with a mechanism for self-correction of triploidy to diploidy. 3PN are also observed in zygotes after conventional in vitro fertilization (IVF). The parental origin, however, differs between the two fertilization methods. Whereas the vast ...

The present study was conducted to examine the development of nuclear transplant embryos produced by transplanting nuclei to either oocytes or zygotes in the mouse. Metaphase II oocytes and one-cell zygotes were enucleated and fused with transferred nuclei from late two-, four- and eight-cell stage embryos. Enucleation of metaphase oocytes was achieved using the interference microscope without ...

The idea of “hopeful monster” was proposed by Goldschmidt who envisioned that speciation could occur instantaneously via major chromosomal rearrangement in a onestep process; but he could not unravel how similar individual in the opposite sex to appear on the same time and location to generate next generation. This paper provides the answer for the challenge. In this paper, a model of speciatio...

BACKGROUND Embryo quality may be accurately assessed as early as the pronuclear zygote phase, as shown in recent studies. However, it is not known whether good quality zygotes are destined to become good quality cleavage stage embryos and blastocysts. METHODS In this retrospective study, 86 intracytoplasmic sperm injection-embryo transfer cycles were studied where each available embryo was sc...