• Ocean and Polar Research
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• 제33권3호
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• pp.303-308
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• 2011

Polar psychrophiles which thrive under extreme conditions such as cold temperature, high salinity, and high dose ultraviolet light, emerge as novel targets for biotechnology. To prevent genetic drift and the possibility of contamination by subculturing, cryopreservation was employed for two psychrophilic microalgae, Porosira sp. (KOPRI AnM0008) and Pyramimonas sp. (KOPRI AnM0046), which have anti-freeze activities. Five cryoprotectants (dimethyl sulphoxide, ethylene glycol, glycerol, methanol and propylene glycol) showed toxicity at 20-30% (v/v). The optimal cryoprotectant concentration and equilibration time were less than 20% and 10 min, respectively. Cryopreservation was carried out in the presence of cryoprotectants either by direct freezing in liquid nitrogen ($LN_2$) or controlled freezing using a controlled rate freezer followed by storage in the $LN_2$ tank. As a result, Pyramimonas sp. (KOPRI AnM0046), a psychrophilic chlorophyta was revived. Cryopreserved Porosira sp. was not revived from either freezing protocols probably due to the silicic cell wall and its relatively large cell size. In the case of Pyramimonas sp. (KOPRI AnM0046), the controlled freezing method showed higher revival yield than the direct freezing method.

• Parasites, Hosts and Diseases
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• 제34권2호
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• pp.155-157
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• 1996

쥐와포자충(MCR주)을 장기간에 걸쳐 그 생명을 유지시키기 위하여 냉동 보존을 시도하였다. 그 오오시스트를 냉동보호제를 첨가하지 않고 증류수에 현탁시켜 $-20^{\circ}C$에서 24시간 예비냉각시킨 다음 $-70^{\circ}C$에 냉동보존하였다. 냉동 오오시스트를 $5^\circ}C$에서 해동시켜 마우스에 접종시킨 바 15개월간 냉동보존시켜토 사멸하지 않고 마우스에의 감염성이 유지되었다. 한편, 2.5% 중크롬산칼륨에 현탁시켜 6.5개월간 $5^{\circ}C$에 냉장한 오오시스트는 이미 사멸하여 감염성이 소실되었다.

• 한국작물학회지
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• 제49권4호
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• pp.354-357
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• 2004

A simplified technique which cryoprotects zygotic embryos by encapsulation-dehydration was developed for the germplasm conservation of herbaceous peony (Paeonia lactiflora Pall.). The highest survival rate $(85\%)$ was obtained from embryos treated by encapsulation-dehydration. The zygotic embryos were precultured on MS medium containing 0.3mg/L $GA_3$ for 1 day. The precultured embryos were encapsulated in $3\%$ (w/v) alginate beads and immersed for 1 h in MS medium containing 2 M glycerol and 0.5 M sucrose. The encapsulated embryos were dehydrated for 5h by air drying prior to direct immersion in liquid nitrogen. This encapsulation-dehydration method appears to be a promising technique for germplasm cryopreservation of a herbaceous peony.

• Journal of Chest Surgery
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• 제23권4호
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• pp.622-639
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• 1990

The use of aortic valve homograft has been developed since 1962 when Ross and Barratt - Boyes independently replaced a diseased aortic valve with an orthotopically inserted homograft valve. And also surgical treatment of complex congenital cardiac malformations utilizing homograft extracardiac conduit has been tried with better result than any other prosthetic material. The present study was undertaken to clarify the safety tissue viability, sterility, after following our protocol of procurement of heart, dissection of aortic and pulmonic homograft, sterilization, cryopreservation, thawing and dilution, and transplantation on experimental animal, sheep. Tissue viability of valve and great artery was assessed by tissue culture. Sterility was evaluated by bacterial and fungal culture. The method used was proven no deleterious effect on the integrity of the valve. Tissue culture of valve tissue before, and after cryopreservation process resulted that active fibroblast growth was observed from homograft sterilized with antibiotics. And culture of the transplanted homograft from sacrificed animal showed active fibroblast growth. Pathologic examination of implanted valve tissue from sacrificed sheep showed mild calcification and minor change, but there were moderate and severe calcification of wall of great arteries.

• Clinical and Experimental Reproductive Medicine
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• 제48권1호
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• pp.11-26
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• 2021

Advances in anticancer treatments have resulted in increasing survival rates among cancer patients. Accordingly, the quality of life after treatment, particularly the preservation of fertility, has gradually emerged as an essential consideration. Cryopreservation of embryos or unfertilized oocytes has been considered as the standard method of fertility preservation among young women facing gonadotoxic chemotherapy. Other methods, including ovarian suppression and ovarian tissue cryopreservation, have been considered experimental. Recent large-scale randomized controlled trials have demonstrated that temporary ovarian suppression using gonadotropin-releasing hormone agonists (GnRHa) during chemotherapy is beneficial for preventing chemotherapy-induced premature ovarian insufficiency in breast cancer patients. It should also be emphasized that GnRHa use during chemotherapy does not replace established fertility preservation methods. All young women facing gonadotoxic chemotherapy should be counseled about and offered various options for fertility preservation, including both GnRHa use and cryopreservation of embryos, oocytes, and/or ovarian tissue.

• Journal of Genetic Medicine
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• 제5권1호
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• pp.55-60
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• 2008

목 적 : 염색체 검사는 의학의 많은 영역과 혈액종양학 분야에서 중요한 역할을 하고 있다. 세포의 기능을 잘 유지하면서 장기간 보관할 수 있는 가장 효과적인 방법은 냉동보존(cryopreservation)으로 알려져 있으며, 이는 미래에 신기술을 적용할 수 있고 회귀연구를 가능하게 한다. 이에 본 연구에서는 제대혈에서 분리된 단핵세포의 냉동전과 해동후의 염색체 검사 결과를 비교하고자 한다. 방 법 : 실험에 대한 동의서를 획득한 제대혈 1례가 검사되었다. Ficoll-Hypaue로 단핵세포를 분리하였고, DMSO 등 냉동보존을 위한 전처리 후 프로그램 냉동기(Cryomed 1010, 미국)로 냉동하여 질소탱크($-196^{\circ}C$)에 3일간 보관하였고, 급속냉동 후 염색체 검사를 시행하였다. 냉동전과 해동후의 염색체 핵형을 분석하였다. 결 과 : 1례의 제대혈은 3군으로 나누어, 냉동 전 배양과정 없던 CB-1군은 염색체 핵형 검사가 판독 불가능하였으며, 냉동 전 3일간 배양 후 냉동보관을 하였던 CB-2와 CB-3군은 냉동전과 해동후의 염색체 핵형이 판독 가능하였고, 서로 일치하였다. 결 론 : 검체의 분포 불균형과 검체 수가 적다는 제한점이 있으나, 제대혈에서 냉동전과 해동후의 염색체 핵형이 일치하는 결과에서 제대혈 단핵세포의 유전적 안정성과 장기간 보관의 가능성을 예측할 수 있을 것으로 사료된다.

• ALGAE
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• 제18권4호
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• pp.321-331
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• 2003

Cryopreservation of sporothalli of the red alga Porphyra (P. seriata, P. yezoensis, P. tenera, P. pseudolinearis and P. dentata) was performed by the two-step cooling method in liquid nitrogen. The algal samples were suspended in various cryoprotective solutions, and slowly cooled to -40$^{\circ}C$ in 4 hours using a programmed freezer. After the first slow cooling the suspensions with cryoprotectants were immediately immersed in liquid nitrogen. The suspension from the programmed freezer was thawed quickly by agitation of the vial in a water bath at 40°C. When ice in the suspension of cryogenic vial was mostly melted, the vial was transferred to an ice bath for complete melting of the residual ice. The cryoprotectants in the vial were washed off by gradual dilution with seawater. The viability of the cell was assessed with neutral red staining. The viability of Porphyra samples ranged 54.6-70.9% when the mixed suspension of 10% dimethylsulfoxide and 0.5 M sorbitol in 50% seawater used as a cryoprotectant.

• Animal Bioscience
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• 제36권10호
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• pp.1530-1535
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• 2023

Objective: Semen cryopreservation result in decreased sperm parameters and fertilization ability. Sericin exhibits antioxidant activity by reducing lipid peroxidation resulting from free radicals, which can potentially improve cryopreservation outcomes. The present study aimed to examine the efficacy of various sericin concentrations supplemented with a rooster semen-freezing extender on post-thaw semen quality and fertilizing ability of sperm after cryopreservation. Methods: Semen samples were collected from 40 roosters (5 reps), then were pooled, and divided into four groups by the levels of sericin supplementation (0%, 0.25%, 0.50%, and 0.75%) in a freezing extender. Semen suspensions were loaded in medium straw (0.5 mL) and cryopreserved with the traditional liquid nitrogen vapor method. Post-thawed semen was evaluated for sperm motility, sperm viability, and lipid peroxidation. Also, the fertility test was determined. Results: The results showed that supplementation of the freezing extender with 0.50% to 0.75% sericin resulted in greater total motility and progressive motility and lower malondialdehyde levels than the other groups after cryopreservation (p<0.05). However, the viability of 0.75% decreased compared with the value of 0.50% sericin supplementation (p<0.05). Moreover, the fertility and hatchability of total eggs were significantly higher in the 0.50% sericin group than in the other groups (p<0.05). Conclusion: In conclusion, 0.50% sericin is recommended as an alternative component of the freezing extender to improve cryopreserved rooster semen.

• 한국환경농학회지
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• 제36권4호
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• pp.256-262
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• 2017

식물 종자를 비롯한 각종 유전자원을 액체질소에 저장하면 유전형질 특성의 손실 없이 장기간 보존할 수 있다. 본 연구에서 보존조건이 까다로워 단명 종자로 분류되는 들깨 종자를 초저온 동결저장 방법으로 보존할 수 있는지를 조사하였다. 수집한 들깨 품종별 종자의 초기 발아율은 40-95% 수준으로 다양하였는데, 수분함량을 3-8%로 조절한 종자를 액체질소에 처리하여도 발아율은 감소하지 않았다. 종자의 수분함량이 4-5%인 종자의 초저온 처리 후 발아율이 가장 높았으며, 초기 발아율이 낮은 품종에서는 초저온 처리에 의해 발아율이 증가하기도 했다. 인위 노화처리에 따라 종자의 발아율과 ascorbate peroxidase 활성은 감소하였으며, 품종별로 종자의 활력 저하 정도는 크게 달리 나타났다. 대조 처리 종자와 비교하였을 때, 초저온 처리과정에 발생할 수 있는 산화스트레스가 들깨 종자의 활력을 저해하지는 않을 것으로 추정되었다. 따라서 들깨 종자를 4-5% 수분함량으로 건조시켜 초저온 동결 저장하면 활력 손실 없이 장기간 보존할 수 있을 것으로 판단되며, 노화가 급속히 진행되는 품종의 경우에는 고활력 자원을 확보하거나 휴면타파 처리 후 초저온 동결 보존하는 것이 유리할 것으로 생각된다.

• 한국동물생명공학회지
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• 제36권2호
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• pp.106-115
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• 2021

Sperm cryopreservation is an important method of assisted reproductive techniques and storing genetic resources. It plays a vital role in genetic improvement, livestock industrial preservation of endangered species, and clinical practice. Consequently, the cryopreservation technique is well organized through various studies, especially on Korean native cattle (Hanwoo). However, the cryopreservation technique of Korean native brindled cattle, which is one of the native cattle species in Korea, is not well organized. Therefore, it is necessary to develop a Supplementary Table technique for the cryopreservation of Korean native brindled cattle. For this purpose, it is important to first evaluate the quality of the currently produced cryopreserved sperm of Korean native brindled cattle. In this study, we randomly selected 72 individual Korean native brindled cattle semen samples collected from 8 different region research centers and used them to evaluate sperm functions. We focused on the quality evaluation of cryopreserved Korean native brindled cattle semen following the measurement of motion kinematics, capacitation status, intracellular ATP level, sperm motility, and cell viability. Then, the values of each of the eight groups were derived from various sperm parameters of nine individual samples, including sperm motility, kinematics, cellular motility, and intracellular ATP levels, which were used to compare and evaluate sperm function. Overall, differences in various sperm parameters were observed between most of the research centers. Particularly, the deviations of motility and motion kinematics were high according to the sample. Therefore, we suggest that it is necessary to develop a standard method for the cryopreservation of Korean native brindled cattle semen. We also suggest the need for sperm quality evaluation of the cryopreserved semen of Korean native brindled cattle before using artificial insemination to attain a high fertility rate.