Natural freeze-tolerance supports the winter survival of many animals including numerous terrestrial insects, many intertidal marine invertebrates, and selected species of terrestrially hibernating amphibians and reptiles. Freeze-tolerant animals typically endure the conversion of 50% or more of total body water into extracellular ice and employ a suite of adaptations that counter the negative ...

The influence of the synthetic phenylurea cytokinin 4-PU-30 and of the adenin cytokinin kinetin on the chilling and freezing stress of tobacco callus was studied histochemically. The investigations were carried out immediately after the low-temperature stress and after 20 days cultivation. It was established that alcohol dehydrogenase and glutamate dehydrogenase activities decreased but esteras...

streptococcus iniae is one of the most important agents that causes high mortality and losses in rainbow trout farms in iran and the world. these bacteria can affects the consumers and people who deal with aquaculture via affected fish. so, viability of this bacterium in frozen fish and fish product can be useful for health care of consumers. a total of 90 rainbow trout, with average weight of ...

Background: The aim of this study was to develop methods for cryopreservation and long-term maintenance of putative bovine embryonic stem cells (ESCs). Materials and Methods: Putative bovine ESC (bESC) lines (n=3) isolated in conventional medium were used to compare slow-freezing and vitrification. Results: After warming, vitrified cells (96.9%) demonstrated significantly (p<0.05) better surviv...

The colony-forming haptophyte Phaeocystis antarctica is an important primary producer in the Ross Sea, and must survive long periods of darkness and freezing temperature in this extreme environment. We conducted experiments on the responses of P. antarctica-dominated phytoplankton assemblages to prolonged periods of darkness and freezing. Chlorophyll and photosynthetic capacity of the alga decl...