• Development and Reproduction
• /
• v.1 no.1
• /
• pp.29-36
• /
• 1997

Experiments were performed to study the effects of diluents, cryoprotectant, equilibration time, thawing temperature and addition of BSA and egg yolk. Among the various diluents, Alsever's solution was the best for sperm cryopreservation. A combination of Alsever's solution and 15% ethylene glycol showed the better results than others did. Sperm activity indection and survival rate gradually decreased with the equilibration time. The appropriate thawing temperature was 30 ${\pm}1^{\circ}$C. These results indicate that sperm cryopreservation methods can be developed in tiger puffer.

• IMMUNE NETWORK
• /
• v.20 no.4
• /
• pp.34.1-34.8
• /
• 2020

Cryopreservation and thawing of PBMCs are inevitable processes in expanding the scale of experiments in human immunology. Here, we carried out a fundamental study to investigate the detailed effects of PBMC cryopreservation and thawing on transcriptomes. We sorted Tregs from fresh and cryopreserved/thawed PBMCs from an identical donor and performed single-cell RNA-sequencing (scRNA-seq). We found that the cryopreservation and thawing process minimally affects the key molecular features of Tregs, including FOXP3. However, the cryopreserved and thawed sample had a specific cluster with up-regulation of genes for heat shock proteins. Caution may be warranted in interpreting the character of any cluster of cells with heat shock-related properties when cryopreserved and thawed samples are used for scRNA-seq.

• Integrative Medicine Research
• /
• v.6 no.1
• /
• pp.12-18
• /
• 2017

Cryopreservation is a process that preserves organelles, cells, tissues, or any other biological constructs by cooling the samples to very low temperatures. The responses of living cells to ice formation are of theoretical interest and practical relevance. Stem cells and other viable tissues, which have great potential for use in basic research as well as for many medical applications, cannot be stored with simple cooling or freezing for a long time because ice crystal formation, osmotic shock, and membrane damage during freezing and thawing will cause cell death. The successful cryopreservation of cells and tissues has been gradually increasing in recent years, with the use of cryoprotective agents and temperature control equipment. Continuous understanding of the physical and chemical properties that occur in the freezing and thawing cycle will be necessary for the successful cryopreservation of cells or tissues and their clinical applications. In this review, we briefly address representative cryopreservation processes, such as slow freezing and vitrification, and the available cryoprotective agents. In addition, some adverse effects of cryopreservation are mentioned.

• Development and Reproduction
• /
• v.21 no.1
• /
• pp.79-91
• /
• 2017

The aim of this study was to compare the efficacy of cryopreservation methods for ex situ conservation of spermatozoa from far eastern catfish, Silurus asotus. The spermatozoa activity index (SAI) and hatching rates were higher in spermatozoa stored in Alserver's solution than those of spermatozoa stored in glucose solution. The SAI and hatching rates in all experimental groups gradually decreased with increasing duration of storage. Additionally, the SAI and hatching rates gradually decreased with increasing thawing temperatures at all storage durations (P<0.05). Based on the SAI and hatching rates, our results suggest that the optimal cryopreservation conditions of catfish spermatozoa involve storage in Alserver's solution with 15% ethylene glycol, and thawing at $25^{\circ}C$. Cryopreservation of spermatozoa is a useful and reliable technique for conserving gene resources and for artificial propagation of far eastern catfish.

• Journal of Embryo Transfer
• /
• v.4 no.1
• /
• pp.1-13
• /
• 1989

This paper reviews the most important steps that have generated consistent progress in principles and developmental progress of embryo cryopreservation, and also study on freezing procedure and its application by conventional method and current improved method for freezing procedure and its appilcation of embryo cryopreservation in farm animals. Four were of particular interest: 1.The transport of water across the ccli membrane (zona pellucida) during freezing and thawing accordinglyplays a role in determing whether the celi survives. This movement of water is controlied mainly by extracellular phase changes and by the nature and concentration of any cryoprotective agent present. Therates of cooling, freezing and warming, and the intervals over which they are applied are further decisi've factors in determining whether a cryopreservation procedure allows survival after thawing. 2.The first successful deep freezing experiments with sheep morula and blastocysts during the seventies were based on the early procedures used for mouse embryos.Current research during the eighties is developed with the aim of simplifying and improving current procedures such as one-step dilution and rapid or ultra-rapid cooling by using the model of laboratory animals. 3.The conventional method for the embryo cryopreservation is described. An alternative to this method which may result in high survival and also in reducing of the freezing and thawing time is done by combing a permeable cryoprotectant such as glycerol, DMSO or propanediol and a non-permeable compound such as sucrose, trehalose, raffinose or lactose. 4.Finally a different approach to the preservation of embryos, named vitrification, is introduced. This procedure depends upon the ability of concentrated solutions of cryoprotective agents such as glycerol and propanediol to supercool to very low temperature (-196$^{\circ}C$) during rapid cooling before solidifying without formation of ice. However, more complete data are necessary for successful vitrification of blastocysts.

• Journal of Marine Life Science
• /
• v.1 no.1
• /
• pp.70-78
• /
• 2016

Microalgae are of significant importance for future biotechnological applications. Many microalgae banks or laboratories attempt to maintain various microalgae for further research purposes. Cryopreservation has been preferred to reduce a labor-intensive and costly routine sub-culturing. Cryopreservation can also diminish the genetic drift risk. However, cryopreservation as a long term storage of microalgae method are still in developing progress because it cannot be generalized for all microalgae. Microalgae types, cryoprotectant agents (CPAs) types, freezing and thawing methods are the most important factors that should be considered for cryopreservation. In this short review the basic principles and the current advanced of microalgae cryopreservation methods are discussed with a suggested starting parameters for microalgae cryopreservation.

• Korean Journal of Plant Resources
• /
• v.17 no.2
• /
• pp.75-81
• /
• 2004

This study was conducted to investigate effects of cryopreservation by vitrification on the seed germination rate and growth and physiological properties of seedlings of Maackia amurensis. Cryopreservation significantly decreased the germination rate of seeds of M. amurensis, but the reduction of germination rate was mitigated by the treatment of cryoprotectant (plant vitrification solution, PVS2) before plugging into liquid nitrogen and fast thawing rate after cryopreservation. Long-term PVS2 exposure decreased seed germination rate, whereas cryopreservation time didn't have influence on seed germination rate. In addition, growth and physiological properties of seedlings were not affected by PVS2 exposing time and cryopreservation time. Therefore cryopreservation could be widely used as a technique of long-term ex situ conservation without any damage and deterioration of cells or tissues of the forest seeds. However, in order to increase the effect of cryopreservation, we have to develope the lower toxic cryoprotectant and suitable techniques to the structural or chemical properties of a variety of seeds.

• Restorative Dentistry and Endodontics
• /
• v.46 no.2
• /
• pp.26.1-26.15
• /
• 2021

Objectives: The aim of the present systematic review was to investigate the cryopreservation process of dental pulp mesenchymal stromal cells and whether cryopreservation is effective in promoting cell viability and recovery. Materials and Methods: This systematic review was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and the research question was determined using the population, exposure, comparison, and outcomes strategy. Electronic searches were conducted in the PubMed, Cochrane Library, Science Direct, LILACS, and SciELO databases and in the gray literature (dissertations and thesis databases and Google Scholar) for relevant articles published up to March 2019. Clinical trial studies performed with dental pulp of human permanent or primary teeth, containing concrete information regarding the cryopreservation stages, and with cryopreservation performed for a period of at least 1 week were included in this study. Results: The search strategy resulted in the retrieval of 185 publications. After the application of the eligibility criteria, 21 articles were selected for a qualitative analysis. Conclusions: The cryopreservation process must be carried out in 6 stages: tooth disinfection, pulp extraction, cell isolation, cell proliferation, cryopreservation, and thawing. In addition, it can be inferred that the use of dimethyl sulfoxide, programmable freezing, and storage in liquid nitrogen are associated with a high rate of cell viability after thawing and a high rate of cell proliferation in both primary and permanent teeth.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.5
• /
• pp.646-651
• /
• 2016

Cryopreservation of caudal epididymal spermatozoa is an effective technique to conserve genetic potentials of superior dogs when it is not possible to collect ejaculated spermatozoa. Although hen egg yolk is commonly supplemented into the semen extender, active substances within the egg yolk which protect sperm against cryoinjury remain to be discovered. Among its compositions, low-density lipoprotein (LDL) has been reported to have a cryoprotective property for sperm cryopreservation. However, the effects of LDL on dog epididymal spermatozoa during cryopreservation have not yet been investigated. This study aimed to investigate the effects of LDL on epididymal spermatozoa quality following cryopreservation and thawing. After routine castration of 12 dogs, caudal epididymides from individuals were separated from the testes and cut into a few pieces in a Tris-buffer. Spermatozoa recovered from each sample were examined at once for sperm quality and divided into six groups of extender: no LDL, 20% egg yolk, 4%, 8%, 16%, and 24% LDL, before cryopreservation. The sperm aliquots were then equilibrated and conventionally frozen. After thawing, sperm motility, morphology, plasma membrane integrity, and acrosome integrity were evaluated. The results revealed that 4% LDL and 20% egg yolk yielded significantly higher sperm motility (57.69% and 52.69%, respectively, p<0.05) than other LDLs. In addition, 4% LDL yielded the significantly highest plasma membrane integrity (70.54%, p<0.05). In conclusion, the supplementation of 4% LDL in Tris-glucose extender could be applied for cryopreservation of canine epididymal spermatozoa.

• Journal of Genetic Medicine
• /
• v.5 no.1
• /
• pp.55-60
• /
• 2008

Purpose : The ability to perform chromosome analysis of cryopreserved cord blood mononuclear cells is important for future retrospective studies. We compared the karyotypes of cryopreserved cells with cells before cryopreservation. Methods : One cord blood (CB) sample was obtained from normal healthy volunteer. Karyotype analysis was performed before cryopreservation. After mononuclear cell separation with Ficoll-Hypaque, the mononuclear cells were cryopreserved by programmed controlled-rate freezer and then transferred into the liquid nitrogen ($-196^{\circ}C$) for 3 days. After rapid thawing, cytogenetic analysis was performed as the same method for each sample by different conditions. The samples were divided by three groups. The first group was no culture before cryopreservation, the second group was 72 hours culture before cryopreservation, but no 24 hours culture after thawing and the third group was 72 hours culture before cryopreservation and 24 hours culture after thawing. Results : The chromosome analysis was successful in the second and third groups of CB sample. Conclusion : The successful result from CB samples may suggest the usefulness of long-term cryopreservation for retrospective study in various clinical settings including hematologic malignancies.