Mitochondrial function and intracellular distribution is severely affected in in vitro cultured mouse embryos.

Studies of mitochondrial dynamics have identified an intriguing link between energy supply balance and mitochondrial architecture. This suggests that inappropriate culture conditions might inhibit mitochondrial functions, and affect embryonic development. Therefore, this study was conducted to determine whether in vitro culture (IVC) might affect mitochondrial function, distribution, organization (by Mitotracker Green), gene expression on RNA level (by qPCR), and protein expression and localization (by western blot and immunostaining) involved in regulation of mitochondrial functions.

Establishment of a Wisent () Germplasm Bank.

The wisent, or European bison (), belongs to the same family (Bovidae) as the American bison and domestic cattle. The wisent is the largest mammal in Europe, and is called the "Forest Emperor". The wisent is listed as "Vulnerable" on the IUCN Red List, and is protected by international law.

Influence of embryo transfer on embryo preimplantation development.

Objective: To investigate the impact of injection speeds of the transferred load on embryo development.

Design: A laboratory model for in vitro simulation of ET was developed to investigate the impact of varying injection speeds of the transferred load on embryo development.

Setting: Academic research institutes of reproduction biotechnology and private centers of reproductive medicine.

Pressure induced nucleus DNA fragmentation.

Purpose: The present study was designed to investigate the impact of pressure on nuclear DNA integrity in viable cells of mouse blastocysts.

Methods: The blastocysts of hybrid F1 females [(C57Bl/10 J × CBA-H);N = 15] aged 2-3 months were exposed into the pressure impulse lasting ~0.021 s and characterized by a positive pressure peak of ~76 mmHg.

Enucleated GV oocytes as recipients of embryonic nuclei in the G1, S, or G2 stages of the cell cycle.

Universal recipients in the G2 phase of mitotic cell cycle (preactivated oocytes, zygotes, blastomeres) accept embryonic nuclei in all the stages of their cell cycle. To test if recipients in the G2 of meiotic cycle (immature oocytes) are universal recipients, mouse germinal vesicle (GV) oocytes were enucleated and reconstructed with blastomere nuclei in the G1, S, or G2 stages. Analysis of their maturation has shown that about 30% of the G1 nuclei and 60% of G2 nuclei allow for normal metaphase II (MII), both in the oocytes with and without the first polar body (1st PB).

Influence of embryo transfer on blastocyst viability.

Objective: To investigate the impact of injection speeds of the transferred load on embryo viability.

Design: Laboratory model for in vitro simulation of embryo transfer (ET).

Setting: Academic research institutes of reproduction biotechnology and private centers of reproductive medicine.

Mouse zygotes as recipients in embryo cloning.

Zygotes have not been recognized as nuclear recipients since enucleated zygotes receiving nuclei from beyond two-cell stage embryos are not able to form blastocysts. In the present study, a new technique of zygote enucleation is presented, which consists in selectively removing the nuclear membrane with genetic material of pronuclei, but leaving other pronuclear components in the cytoplasm. With selective enucleation it is possible - after transfer of eight-cell stage nuclei - to obtain 70.