Probing metabolism in mouse embryos using Raman spectroscopy and deuterium tags.

The use of deuterated compounds is an interesting opportunity to expand the capabilities of Raman spectroscopy to study metabolism in living cells. Different biological objects have different tolerances to different deuterated compounds, and their metabolic chains may differ. Here, we explore the potential of this approach to probe metabolism in early mouse embryos.

Reversal of crystallization in cryoprotected samples by laser editing.

Advances in cryobiology techniques commonly target either the cooling or the warming cycle, while little thought has been given to ≪repair≫ protocols applicable during cold storage. In particular, crystallization is the dominant threat to cryopreserved samples but proceeds from small nuclei that are innocuous if further growth is forestalled. To this end, we propose a laser editing technique that locally heats individual crystals above their melting point by a focused nanosecond pulse, followed by amorphization during rapid resolidification.

Effects of stearic acid on the embryo cryopreservation in mouse.

Background: Intracellular lipids are sensitive to freezing. Lipidome modification is an important tool for studying the role of intracellular lipids in cryotolerance of mammalian oocytes and preimplantation embryos.

Objective: To study the effects of in vitro exposure of murine embryos to saturated stearic acid (SA) on the lipid content, embryo development and cryotolerance.

Irreversible lipid phase transition detected in a porcine oocyte at chilling.

Under physiological conditions, the membranes and lipid droplets of germ cells are in a conformationally disordered phase. Typically, during cooling, lipids undergo the transition to ordered phases and, upon heating, melt into a disordered phase. In this communication, we report the lipid phase transition in lipid droplets observed in porcine oocytes.

Program freezing of diapausing embryos in the mouse.

Embryonal diapause is a characteristic feature of about 130 mammalian species. However, very few studies have addressed cryopreservation of diapausing embryos. This work is aimed to apply program freezing to blastocysts obtained from CD1 mice, which were at diapause state after ovariectomy and the subsequent hormonal therapy.