OBJECTIVE In vitro culture of preimplantation embryos is improved by grouping embryos together in a drop of media. Individually cultured embryos are deprived of paracrine factors; with this in mind, we investigated whether the addition of a single embryo-secreted factor, interleukin-6 (IL-6), could improve the development of individually cultured embryos. METHODS Mouse embryos were cultured i...

  SUMMARY Since at oocyte retrieval for in vitro fertilization there is some FF become incorporate to egg, we decided to investigate the effect of this fluid on preimplantation embryo development in vitro. FF was obtained at the time of oocyte retrieval for IVF, centrifuged and then either inactivated by heat and stored at 4°c or without inactivation stored at-20°c until used. Late 2-cell emb...

Background: The advances in cytogenetic techniques during the last few years have permitted not only the study of large populations of wild and domestic animals, but also the detection of chromosome anomalies in embryos. Chromosomal abnormalities are the most common cause of embryonic and fetal mortality in mammals. Most reports of chromosome anomalies in parthenogenetic embryos describe numeri...

A microsurgical grafting technique has been used to introduce primordial germ cell (PGC) precursors into intact primitive-streak-stage mouse embryos in vitro. Operated embryos were cultured for 36-40 h and then analysed by a combined histochemical and autoradiographic method. PGC chimaerism occurred in embryos that received grafts of caudal primitive streak cells but not adjacent embryonic endo...

The cdk1/cyclin B1 complex is a universal regulator known to be responsible for driving the cell-cycle from the G2- to the M-phase. To investigate the effects of irradiation on the activity of this complex in preimplantation embryos, we irradiated one- and two-cell mouse embryos with X-rays, and measured the fluctuations of histone H1 and cdk1 kinase activity. Four mouse strains with different ...