Cryobank of plant genetic resources in Russian Academy of Sciences

Cryopreservation is the most reliable method for long-term storage of plant genetic resources. A review of cell injury by ice crystals and dehydration during a freeze–thaw cycle is given. For successful regeneration of plants and cultures after cryopreservation of their cells, the development of reliable cryopreservation procedure is required including preliminary cultivation, treatment by cryoprotectors, freezing by different methods, thawing and recultivation. Up to now 27 cell lines successfully resumed their growth after storage in liquid nitrogen and preserved their specific features and biosynthetic potential. Besides, shoot tips of 40 cultivars of potato, rose, strawberry and raspberry regenerated plants both in vitro and in vivo after cryopreservation. The longest storage duration was 25 years. Now in liquid nitrogen we continuously store 24 cell strains of rare medicinal plants, shoot tips of seven cultivars of strawberry and raspberry and seeds of 250 endangered plant species collected over all Russian territory.     

人类冷冻精子经卵黄缓冲液冷处理后的受精率变化

本研究应用人精子－去透明带地鼠卵穿透试验（SPA），探讨了人类冷冻精子经卵黄缓冲液4℃冷处理后的受精率改变。结果表明，卵黄液对冷冻精子SAP受精率有改善的效应，但这种效应存在明显的标本差异。     

The Phospholipid Composition of Kangaroo Spermatozoa Verified by Mass Spectrometric Lipid Analysis

Cryopreservation of kangaroo sperm has not been successful so far, and yet there is no promising cryopreservation protocol for these cells available. However, conservation of gametes is extremely important, particularly in the context of preserving endangered species. As spermatozoa are comprised of different membrane systems, the composition of these membranes might account for difficulties in cryopreservation. Lipids, as the main components, affect the physical properties of biological membranes and play a major role in sperm maturation. Therefore, knowledge of the lipid composition is crucial for any further step toward the preservation of the species. We used MALDI‐TOF, ESI‐IT, tandem mass spectrometry, and thin layer chromatography to investigate the lipid composition of epididymal spermatozoa of four different kangaroo species. Spectra of these species were very similar with respect to the identified lipid species. Tremendous changes in the lipid composition during the transit of sperm from caput to cauda epididymis could be seen, specifically an increase in poly‐unsaturated fatty acids, ether lipids, and plasmalogens, as well as a reduction in mono‐ and di‐unsaturated fatty acids. Additionally, phosphatidylcholines containing docosatrienoic acid (22:3), a heretofore unknown fatty acid for sperm membranes, showed the highest abundance in kangaroo sperm.     

用于酶热传感器的酶标甲胺磷农药的低温贮存研究

采用加速实验中获得的较优保护剂配方(2.0mol/L氯化钠、4.0mol/L木糖醇、1.25mol/L甘油),对酶热传感器中酶标甲胺磷农药低温贮存过程中的酶活变化进行了研究。结果显示:加或未加复合保护剂时,酶标农药的贮存温度与酶活损失速率常数之间符合Arrhenius关系,且酶标农药-18℃条件下贮存6个月后,酶活保留率分别为77.13%(未加保护剂)和97.44%(加保护剂)。与化学动力学方法获得的理论预测值相比,相对标准偏差分别为3.10%(未加保护剂)和0.51%(加保护剂)。这一结果将为下一步的农残检测酶热传感器的开发奠定基础。     

糖醇类物质对人肝细胞低温保存的影响

将传统肝细胞冻存保护剂配方中的DMSO的浓度减为5%,并添加不同浓度的D-山梨醇、木糖醇或麦芽糖醇,置于-80℃的冰箱冻存两周,两周后将细胞快速复温,进行细胞存活率、24h贴壁率以及细胞形态学的检测,并与10%浓度DMSO组对照比较。结果表明,D-山梨醇、木糖醇、麦芽糖醇均对人肝细胞的低温保存有一定的保护作用,其中5%DMSO+0.4M D-山梨醇组复温后细胞的存活率、贴壁率均优于其他冻存液组,D-山梨醇与DMSO联合使用降低了冻存保护剂DMSO的浓度,表明两者有协同作用。     

寄生虫低温保存的研究现状

传统的寄生虫保存方法有体外培养和动物转种,这些方法操作繁琐,成本较高,而且易发生遗传漂变、人为差错或混淆等问题。低温保存寄生虫可克服传统保存方法的弊端,并可保持寄生虫原有的生物学特性。本文就低温保存寄生虫的种类及主要影响因素作一综述,为寄生虫低温保存的研究提供参考。     

低温冷冻对CIK细胞诱导及活性影响的研究

目的 研究低温冷冻对CIK(cytokine-induced killer cells)细胞诱导及活性的影响,方法 用经过程序降温仪冷冻后的脐血单个核细胞定向诱导CIK细胞,其活性与用新鲜的脐血单个核细胞定向诱导生成的CIK细胞进行比较,并对冷冻过的经21d诱导生成的CIK细胞,与未冻存过的细胞进行活性比较。用乳酸脱氢酶(LDH)分析法分析细胞毒活性,用流式细胞分析仪分析CIK细胞的纯度。结果 冻存后的脐血单个核细胞诱导生成的CIK细胞在扩增能力、纯度和细胞毒性方面与新鲜细胞诱导生成的CIK细胞无明显差异;经过冻存的CIK细胞在纯度和细胞毒性方面与未冻存前也无明显差异。结论 对于CIK细胞的临床应用具有指导意义。     

生物档案系统在脐带血冻存中的应用

BioArchive System(生物档案系统)是ThermoGenesis公司开发的专门用于脐带血造血干细胞冻存的设备。其集程控降温和冷冻保存于一体。我们采用该设备冻存311份脐带血,结果表明生物档案系统具有冻存效果良好、操作方便和节约空间等优点,是同类产品中最先进的仪器。     

Cellular cryobiology: thermodynamic and mechanical effects

Several physical stresses kill cells at low temperatures. Intracellular ice is usually fatal, so survival of freezing temperatures involves combinations of dehydration, freezing point depression, supercooling and intracellular vitrification. Artificial cryopreservation achieves intracellular vitrification with rapid cooling, modest osmotic contraction and, often, added cryoprotectants. High warming rates are required to avoid crystallization during warming. Environmental cooling is much slower and temperatures less cold, but environmental freezing damage is important ecologically and agronomically. For modest sub-freezing temperatures, supercooling sometimes allows survival. At lower temperatures, extracellular water usually freezes and cells may suffer large osmotic contractions. This contraction concentrates solutes and thus assists vitrification, but is not necessarily reversible: the rapid osmotic expansion during thawing may rupture membranes. Further, membranes and other ultrastructural elements may be damaged by the large, anisotropic mechanical stresses produced when their surfaces interact via hydration forces. Solutes reduce these stresses by osmotic, volumetric and other effects.