Sexual and asexual lines of the unicellular chlorophyte Chlamydomonas reinhardtii were propagated for about 100 sexual cycles and 1000 vegetative cycles in contrasted environments, liquid and solid growth media, in order to generate divergent natural and sexual selection. Sexual lines were transferred by many zygotes or by a single zygote in each sexual generation. By the end of the experiment ...

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.

introduction: pronuclear size, morphology and orientation are known to affect embryo quality and implantation. the present study was aimed at evaluation of the possible relationship between protamine deficiency with pronuclear morphology and also cleavage and embryo quality. material and methods: semen sample of 160 candidate icsi and ivf couples were analyzed for sperm concentration, and motil...

BACKGROUND Many factors from the oocyte/sperm or the process of fertilization may affect the zygote formation. The zygote score (Z-score) describes the quality of a human zygote based on its pronuclear morphology, nucleolar precursor bodies, and alignment of polar bodies, and it can be used in the selection process at the zygote stage for embryo transfer or cryopreservation. OBJECTIVE The aim...

background: the cells of mammalian female reproductive tract have been widely used for in vitro fertilization (ivf). this study was designed to study the effects of oviductal epithelial cells (oecs) and their conditioned medium during ivf on subsequent embryonic development and the relative abundance of zygote arrest 1 (zar1) transcript in ovine zygotes. methods: the in vitro matured ovine oocy...

BACKGROUND Several randomized controlled trials have not shown a benefit from preimplantation genetic screening (PGS) biopsy of cleavage-stage embryos and assessment of up to 10 chromosomes for aneuploidy. Therefore, a proof-of-principle study was planned to determine the reliability of alternative form of PGS, i.e. PGS by polar body (PB) biopsy, with whole genome amplification and microarray-b...

Rare conjugational progeny formed by crossing each of five Hfr strains with a recA-F- strain have been characterized. Selection was made for a proximal Hfr marker, taking strict precautions to prevent transfer of recA+ to the zygotes. Most of the progeny were found to be F' strains containing deletion mutant plasmids. With two exceptions, these mutant plasmids have lost all of the tra genes, wh...

BACKGROUND The development of the mouse zygote following fertilization in vitro in a KSOM-type medium containing either L-glutamine or glycyl-L-glutamine has been examined, and compared with the development of mouse zygotes produced by natural fertilization. METHODS Mouse IVF, embryo culture and embryo transfer. RESULTS Fertilization rates, development to the blastocyst stage, implantation ...