The sensitivity of early preimplantation mouse embryos to drugs which disrupt microfilament function (cytochalasin B-CB and cytochalasin D-CD and microtubule assembly (colchicine, colcemid, vinblastine and griseofulvin) was examined. CD inhibited cleavage at a concentration 35-fold lower than CB (3 X 10-7 M v. 1 X 10-5 M). Treatment of 2-cell embryos for 6 h with 1 X 10-5 M CB or 1 X 10-6 M CD...

In this prospective randomized study on 1380 consecutive in-vitro fertilization (IVF) treatments, the results were compared of culture of human oocytes and embryos for the first 2 or 3 days of development in microdroplets of medium under oil using a gas phase containing either atmospheric (approximately 20%) or reduced (5%) O2 concentrations. No significant differences were found between the tw...

The effects of mechanical vibration during in vitro maturation and/or in vitro culture after artificial activation of pig oocytes on maturation and development were examined. In addition, the optimal conditions were applied to in vitro production of blastocysts derived from miniature pig somatic cell nuclear transfer (SCNT) embryos. Mechanical vibration during in vitro maturation did not affect...

Eleven patients underwent controlled ovarian hyperstimulation yielding 72 embryos for evaluation. Mean nitric oxide metabolite levels in the insemination media were 2.6 times higher in embryos that progressed to blastocysts by culture day 5 than in those that did not. A comparison of the receiver operating characteristic curves between morphological predictors and nitric oxide metabolite levels...

Analysis of the developmental capacities of androgenetic and gynogenetic mouse embryos (bearing two paternal or two maternal pronuclei, respectively) revealed a defect in blastocyst formation of androgenetic, but not gynogenetic, embryos that was a function of the maternal genotype. Androgenetic embryos constructed using fertilized eggs from C57BL/6 or (B6D2)F1 mice developed to the blastocyst ...

The study investigated the feasibility of lyophilization for long-term preservation of somatic cells and embryonic development after whole cell intracytoplasmic injection (WCICI) into enucleated pig oocyte. Confluent cultured porcine fetal fibroblast (pFF) cells were lyophilized and stored at 4°C for at least 6 months. Results showed that compared to non-lyophilized control cells, lyophilized c...

The present study was designed as 5 x 4 factorial to investigate the effects of using sperm from 5 bulls, and varied sperm-oocyte incubation times (5, 10, 15 and 20 h) on the fertilization, cleavage rates and blastocyst formation on an in vitro bovine embryo production system. The bulls included a tetraparental Chimera, its sires (Japanese Black and Limousin), its maternal grand-sires (Japanese...

This paper reports studies on the effects of re-vitrification by the CPS (Closed Pulled Straw) method on the development of 4-cell stage mouse embryos. The procedure involved culturing 2-cell mouse embryos in G-1 medium until the 4-cell stage followed by the division of the normal 4-cell stage embryos into a control group (non-vitrified) and two experimental subgroups (vitrified and re-vitrifie...

Elevated CO(2) is required for in vitro embryo culture to maintain proper media pH and to supply embryo metabolic pathways. As an alternative to current approaches using gas cylinders, we examined use of a chemical reaction to supply CO(2). A closed culture system was constructed and chemicals added to generate CO(2), which was then supplied to developing embryos. This system was shown to provi...

Although mosaicism was shown to be a normal feature in cleaving embryos, its consequences for the late preimplantation stages are unknown. We performed blastocyst immunosurgery, followed by fluorescent in-situ hybridization (FISH), to determine the number of cells and degree of mosaicism in the inner cell mass (ICM) of human blastocysts. Of 47 ICM samples analysed, 20 had aneuploid cells, and t...