Search results for "Cryobiology"
showing 4 items of 4 documents
Semen characteristics and their ability to predict sperm cryopreservation potential of Atlantic cod, Gadus morhua L.
2010
There is a lack of biomarkers or indices that can be used to predict the quality of fish semen samples following the freezing and thawing cycle. In the present study, a series of semen indices were tested to assess if they could accurately forecast the cryopreservation potential of Atlantic cod (Gadus morhua) semen. Fresh and frozen-thawed sperm activity variables were compared, and relationships between frozen-thawed sperm activity and fertilization success were examined. In comparison with fresh sperm, activity variables of frozen-thawed spermatozoa were reduced. Of the 18 males examined, mean (± SEM) spermatocrit of fresh sperm was 40.72 ± 4.23%, osmolality of the seminal plasma 366.32 ±…
Cell inactivation and membrane damage after long-term treatments at sub-zero temperature in the supercooled and frozen states.
2008
The survival of cells subjected to cooling at sub-zero temperature is of paramount concern in cryobiology. The susceptibility of cells to cryopreservation processes, especially freeze-thawing, stimulated considerable interest in better understanding the mechanisms leading to cell injury and inactivation. In this study, we assessed the viability of cells subjected to cold stress, through long-term supercooling experiments, versus freeze-thawing stress. The viability of Escherichia coli, Saccharomyces cerevisiae, and leukemia cells were assessed over time. Supercooled conditions were maintained for 71 days at -10 degrees C, and for 4 h at -15 degrees C, and -20 degrees C, without additives or…
Vitrification of Immature Porcine Oocytes: Effects of Lipid Droplets, Temperature, Cytoskeleton, and Addition and Removal of Cryoprotectant
1998
Three experiments were conducted to investigate the effects of single-step and stepwise exposure to and removal of cryoprotectant, of temperature, and of a cytoskeletal relaxant on the development of germinal vesicle porcine oocytes to the M-II stage. In experiment I, noncooled cumulus-oocyte complexes (COCs) were treated using single-step/stepwise exposure to ethylene glycol (EG) and removal at 23 or 42 degrees C. Stepwise exposure to EG and dilution at 42 degrees C were found to have a positive effect on the COC developmental rate. In experiment II, also without cooling, COCs were treated with Cytochalasin B at 42 degrees C using single-step and stepwise protocols of exposure to and remov…
A Method for the Cryopreservation of Liver Parenchymal Cells for Studies of Xenobiotics
1993
Abstract An optimized computer-controlled freezing protocol for the cryopreservation of rat liver parenchymal cells was developed. The best survival rates were obtained when a slow cooling rate was used and when the supercooling was interrupted with a shock cooling to initiate ice nucleation. Ten percent dimethyl sulfoxide was added and removed gradually for best results. Thawed rat liver parenchymal cells had a viability, as judged by trypan blue exclusion, of 69% (SD = 6) versus 82% (SD = 7) for freshly isolated cells. The content and activities of the xenobiotic metabolizing enzymes, cytochrome P450. UDP-glucuronosyl transferase, and microsomal and cytosolic epoxide hydrolase, were not a…