2016年1月22日

玻璃化冷凍精蟲可提高存活率
含0.5M sucrose玻璃化冷凍液用於冷凍精蟲,
可提高存活率達80%(傳統glycerol+蛋黃冷凍僅30-40%)


http://c.ymcdn.com/sites/www.iffs-reproduction.org/resource/resmgr/press_room/sanchez_final.pdf

Press release - International Federation of Fertility Societies EMBARGO: 00.01 Central European Summer Time Tuesday 14 September 2010 New sperm-freezing technique dramatically improves viability of frozen sperm, and may allow safe use of sperm from HIV+ men A new technique for freezing sperm can dramatically increase the viability of frozen sperm. In addition, as the technique does not involve the freezing of seminal plasma, it holds out the possibility of allowing sperm from HIV+ men to be used without the danger of transmitting the virus. The technique has been developed by a team from Temuco (Chile) and Ulm (Germany), led by Professor Raul Sanchez (La Frontera University, Temuco, CHILE), and is presented at the World Congress of Fertility and Sterility in Munich, Germany. Currently, sperm is frozen slowly and then stored in liquid nitrogen at –160 C. This technique allows recovery of around 30 to 40% activity. However the current technique has drawbacks, including loss of motility and vitality, and damage to the membrane The new technique is called sperm vitrification (egg and embryo vitrification are already in use in fertility clinics). Sperm are centrifuged to remove the plasma components, and then resuspended in a sucrose solution before being plunged into liquid nitrogen to fastfreeze. The vitrified sperm can then be stored either in liquid nitrogen or in an ultra-cold deep freeze at -86ºC. This gives several advantages over the existing method, including a significant increase in motility of the rethawed sperm (77% motility versus 29% using current methods). In addition, it seems that the sperm are less damaged by the vitrification technique. It means that a higher concentration of viable sperm can be recovered prior to IVF techniques such as ICSI, which will give a greater chance of fertilization. As a by-product of the technique, the removal of the sperm plasma means that the technique will separate the sperm from many contaminating agents, such as HIV and other viruses, giving HIV+ men the chance to father children without the likelihood of passing on the virus to the mother and child.

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