We have evaluated the safety of intracytoplasmic sperm injection(ICSI) procedures by using bovine zygotes. Bovine zygotes were injected with a small amount (2-3 pl) of either medium alone or medium containing polyvinylpyrrolidone (PVP) (sham-ICSI, without spermatozoon) using the same procedure as ICSI, and the subsequent in-vitro embryonic development and embryo quality (number of cells/blastoc...

It is generally assumed that light has no effect on the physiology of oocytes, zygotes, or early embryos. Therefore, little or no attention has been paid to lighting conditions during the handling of these cells in vitro. Here we show that cool white fluorescent light, rich in short-wavelength visible light and commonly used in research and clinical laboratories, produces more reactive oxygen s...

We classify, up to homeomorphism, all closed manifolds having the homotopy type of a connected sum of two copies of real projective n-space. 1. Statement of results Let P = Pn(R) be real projective n-space. López de Medrano [LdM71] and C.T.C. Wall [Wal68, Wal99] classified, up to PL homeomorphism, all closed PL manifolds homotopy equivalent to P when n > 4. This was extended to the topological ...

The effect of pronuclear microinjection of DNA and culture in excised mouse oviducts on the development of porcine zygotes was assessed in this study. Precocious ovulation was induced in prepubertal gilts with pregnant mare's serum gonadotrophin and hCG. Zygotes received either pronuclear microinjection of buffer alone, buffer containing a DNA construct, or no microinjection. Zygotes were cultu...

Because the diploid human embryonic stem cells (hESCs) can be successfully derived from tripronuclear zygotes thus, they can serve as an alternative source of derivation of normal karyotype hESC lines. The aim of the present study was to compare the pluripotency and trophoblast differentiation ability of hESCs derived from tripronuclear zygotes and diploid hESCs. In the present study, a total o...

The CRISPR/Cas system is an efficient genome-editing tool to modify genes in mouse zygotes. However, only the Streptococcus pyogenes Cas9 (SpCas9) has been systematically tested for generating gene-modified mice. The protospacer adjacent motif (PAM, 5'-NGG-3') recognized by SpCas9 limits the number of potential target sites for this system. Staphylococcus aureus Cas9 (SaCas9), with its smaller ...

Although around 1-4% of human zygotes have been found to be tripronuclear, there is little information about the subsequent development and chromosomal composition of embryos that derive from these zygotes. Herein, we report a pregnancy and subsequent delivery of a healthy newborn after the transfer of a blastocyst that developed from a tripronuclear zygote that had a euploid microarray result.

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...