This article introduces cryosurgery devices, cryopreservation devices, some cryogenic freezing methods in medicine and the recent progress about cryotherapy technology.
Cryopreservation ; instrumentation ; Cryotherapy ; instrumentation ; methods

Vitrification, as a cryoprotective method for freezing cells or tissues at very high cooling rates, can avoid the formation of intracellular ice crystals that are potentially lethal during freezing and thawing, and maximally reduce the damage to cells. Considerable progress has been achieved in the cryopreservation of human gametes and embryos. Vitrification has been used to successfully cryopreserve immature and mature oocytes, spermatozoa and embryos at various developmental stages in the last decade, and has led to the birth of many healthy babies. Vitrification, with its simple operation and rapid process, is becoming one of the important techniques in human assisted reproduction.
Cryopreservation ; methods ; Humans ; Reproductive Techniques, Assisted

In this paper we studied cryopreservation of Cyclamen persicum Mill. callus to avoid variations produced by sub-culture. The callus in the logarithmic phase after sub-culture were used for experiments. Firstly, the callus were pre-cultured in culture-medium containing 4%, 6% or 8% sucrose for different time periods, transferred to different cryoprotectants to directly cryopreserve or incubated for 2 hours at -20 degrees C, then submersed in liquid nitrogen, lastly thawed rapidly in a waterbath at 37 degrees C, and washed with liquid culture-medium containing the corresponding concentration of sucrose. Cell survival rate was computed after stained by Neutral Red, and SPSS 13.0 software was used for statistical analysis. The results showed that sucrose concentration, pre-culture time, cryoprotectants had various impacts on cell survival rate. We have developed a simple but effective protocol for the cryopreservation of callus of C. persicum. Of the different protocols tested, 4%sucrose, pre-culturing for 3 days, No. 9 cryoprotectant and freezing directly after 30 minutes at 0 degrees C results in the highest cell survival rate.
Cryopreservation ; Culture Techniques ; methods ; Cyclamen ; growth & development

Despite the worldwide application of sperm-freezing technology as a means of preserving male fertility functions, few reports are seen about the transmission of microorganisms to cryopreserved sperm via contaminated liquid nitrogen (LN). Although the risk of cross-contamination between samples stored in liquid nitrogen is "vanishingly small", it must be accepted as a finite risk and all reasonable measures taken to reduce the likelihood of its occurrence. Moreover, all methods employed, including collection, cryopreservation, storage and thawing of human sperm as well as the clinical use of cryobanked human sperm, must reduce the risk of contamination from any source throughout the entire process.
Cryopreservation ; methods ; Equipment Contamination ; Humans ; Male ; Semen Preservation ; methods

Human sperm cryopreservation is an increasingly mature technique in assisted reproduction. However, conventional sperm cryopreservation is not suitable for the cryopreservation of small numbers of sperm. The solution to the cryopreservation of small numbers of sperm may contribute a lot to the clinical treatment of asthenospermia, oligospermia and azoospermatism. Recently, many researchers focus on searching for appropriate carriers for the cryopreservation of small numbers of sperm. This article outlines the effects of current cryopreservation methods including empty zona pellucida, microdrops, other mocrocarriers, testicular tissue cryopreservation and testicular sperm and epididymal sperm refrigeration.
Cryopreservation ; methods ; Humans ; Male ; Semen Preservation ; methods ; Testis

Vitrification of human oocytes and embryos has become an important assisted reproductive technology. It can be used to cryopreserve immature oocytes, mature oocytes, pronuclear embryos, blastomeres, and blastocysts. This article reviewed the clinical application of vitrification of human oocytes and embryos at different developmental stages.
Cryopreservation ; methods ; Embryo, Mammalian ; Humans ; Oocytes ; Reproductive Techniques, Assisted

OBJECTIVETo explore the feasibility and safety of microdrop-vitrification for epididymal spermatozoa obtained by percutaneous epididymal sperm aspiration (PESA) without cryoprotectants.

METHODSWe treated the epididymal sperm samples from 22 patients by conventional freezing (Group 1) and microdrop-vitrification without cryoprotectants (Group 2), and evaluated the effectiveness of the two methods by comparing their revival rate, retrieval rate and incidence of sperm nuclear DNA fractures.

RESULTSMotile sperm were found in all but 1 case in Group 1. The revival rates of the frozen sperm were low in both Groups 1 and 2 ([18.16 +/- 9.38]% vs [21.99 +/- 10.95]%, P > 0.05), but statistically significant differences were shown between the two groups in the retrieval rate ([58.39 +/- 12.67]% vs [70.82 +/- 14.94]%, P < 0.01). Before freezing, nuclear DNA fractures existed in the epididymal sperm samples of all the 22 patients, comet sperm were seen after unicellular gel electrophoresis, and the incidence of sperm nuclear DNA fracture was (26.68 +/- 9.45)%. After freezing, no increase was observed in the incidence of sperm nuclear DNA fracture in either Group 1 or 2 ([28.68 +/- 12.54]% vs [27.64 +/- 10.70]%, P > 0.05).

CONCLUSIONMicrodrop can be used as a suitable freezing carrier for a low number of sperm, and cryoprotectant-free vitrification with microdrop may be a simple, safe and effective method for the cryopreservation of a low number of epididymal sperm.

Cryopreservation is essential for the long-term storage and banking of cartilage grafts. This paper reviews the developments on the cryopreservation of cartilage and transplantation of cryopreserved cartilage grafts during the past 10 years. It is stated that the current technologies for cryopreservation of cartilage grafts are not mature. Further systematic studies are necessary.
Animals ; Cartilage ; transplantation ; Cryopreservation ; Humans ; Tissue Preservation ; methods

OBJECTIVETo evaluate the safety and risk of cryopreservation in female fertility preservation.

DATA SOURCESThe data analyzed in this review were the English articles from 1980 to 2013 from journal databases, primarily PubMed and Google scholar. The criteria used in the literature search show as following: (1) human; embryo; cryopreservation/freezing/vitrification, (2) human; oocyte/immature oocyte; cryopreservation/ freezing/vitrification, (3) human; ovarian tissue transplantation; cryopreservation/freezing/vitrification, (4) human; aneuploidy/DNA damage/epigenetic; cryopreservation/freezing/vitrification, and (5) human; fertility preservation; maternal age.

STUDY SELECTIONThe risk ratios based on survival rate, maturation rate, fertilization rate, cleavage rate, implantation rate, pregnancy rate, and clinical risk rate were acquired from relevant meta-analysis studies. These studies included randomized controlled trials or studies with one of the primary outcome measures covering cryopreservation of human mature oocytes, embryos, and ovarian tissues within the last 7 years (from 2006 to 2013, since the pregnancy rates of oocyte vitrification were significantly increased due to the improved techniques). The data involving immature oocyte cryopreservation obtained from individual studies was also reviewed by the authors.

RESULTSVitrifications of mature oocytes and embryos obtained better clinical outcomes and did not increase the risks of DNA damage, spindle configuration, embryonic aneuploidy, and genomic imprinting as compared with fresh and slow-freezing procedures, respectively.

CONCLUSIONSBoth embryo and oocyte vitrifications are safe applications in female fertility preservation.

Human sperm cryopreservation has been widely applied in human assisted reproduction technologies, but ultra-low temperature may damage the structure and function of sperm, which in turn may affect the success rate of human reproductive technology. However, this view is not yet universally accepted. Researchers around the world are endeavoring for the mechanisms of cyrodamage and discoveries of cryo-protection. This article gives an overview on the types of human sperm cryodamage, mechanisms of sperm functional changes, and latest discoveries of cryo-protection.
Cryopreservation ; Humans ; Male ; Semen Preservation ; adverse effects ; methods