to mutate the ice nucleation active (ina) gene in erwinia herbicola strains, tn-5 transposon carried by psup2021 plasmid was used. this plasmid was transferred to the bacterial cells by electroporation. electrotransformation was carried out for 2.5 ms at 1800 v and 1 mm distance between the electrodes. polymerase chain reaction was used for determination of presence or loss of ina gene, using a...

During winter, larvae of the Antarctic midge, Belgica antarctica (Diptera, Chironomidae), must endure 7-8 months of continuous subzero temperatures, encasement in a matrix of soil and ice, and severely desiccating conditions. This environment, along with the fact that larvae possess a high rate of water loss and are extremely tolerant of desiccation, may promote the use of cryoprotective dehydr...

T he emerging field of tissue engineering has identified product storage as a significant obstacle for commercialization of products containing living cells. Traditionally employed methods of tissue banking utilize cryopreservation by freezing. Unfortunately, cryopreservation by freezing may result in loss of tissue function and viability by several recognized mechanisms of which ice formation ...

In this study, a survey was conducted to both evaluate the consumers' general attitudes for purchasing and storing the raw chicken and determine the thawing practices used for defrosting frozen chicken at home. About 75% of the consumers indicated purchasing chicken meat at least once a week or more. Furthermore, the majority (82.16%) of those who stored at least a portion of the raw chicken st...

Falls and freezing of gait are two "episodic" phenomena that are common in Parkinson's disease. Both symptoms are often incapacitating for affected patients, as the associated physical and psychosocial consequences have a great impact on the patients' quality of life, and survival is diminished. Furthermore, the resultant loss of independence and the treatment costs of injuries add substantiall...

There have been few reports on the preservation of viruses at the temperature of liquid nitrogen (-196 C). In this study, factors affecting the survival of phage were observed. Phage lysates in broth did not lose titer after a storage period of 4 weeks in liquid nitrogen. The rate of freezing was not critical, but freezing in nitrogen vapor was not satisfactory. When the virus was partially pur...

Bioavailability of dietary folate might be impaired by the polyglutamate chain to which approximately 70% of dietary folates are bound. This chain must be removed enzymatically in the intestine before folate is absorbed as a monoglutamate. To increase formation of monoglutamate folate in vegetables, the vegetables were subjected to various processing treatments. Treatments included freezing (-1...

Large scale extraction and assay of the lymphocyte chalone (LC), the natural lymphocyte proliferation inhibitor, require optimized, reproducible and standardizable methods. To this end we compared the effects on LC yield of storing thymus at different temperatures after collection from calves: Both quick freezing on solid CO2 and slow freezing at -50 degrees C led to a 30% loss of LC yield rela...

Heparinized whole blood, parasitized with Aegyptianella pullorum, was collected from 2 fowls. Buffered lactose peptone (BLP) was added v/v as a stabilizer and the mixture lyophilized in 2 ml aliquots after rapid or slow freezing. At different stages during the freeze-drying process, as well as after lyophilization and reconstitution with 1.8 ml of sterile water, samples were taken and injected ...