医药洁净冷胚间设计与施工

药厂生物疫苗类项目,洁净冷胚间的功能相当重要,其温度让病毒和鸡胚停止生长,大概10h,完全冷后再收获。现某疫苗项目冷胚间温度要求为2℃,相对湿度要求为45%~65%,如何在满足温度的同时满足湿度要求,满足货架竖向布置中所有格层的温度的均匀性,满足GMP对医药洁净室洁净度要求,是洁净冷胚间的设计及施工难点,也是本项目成败的关键点。

鸡胚疫苗原液上游工序洁净空调系统的建设

总结了鸡胚疫苗原液上游生产工序中的毒种制备、前孵化、接毒、后孵化、冷胚、收获工序的需求,分析了不同生产工序相对应的洁净空调系统在设计及工程建设过程中应关注的内容,以便企业提高生产效率,降低生物安全风险。

Research Progress on Technique of Frozen Embryo Transfer in Sheep

The paper introduced the research progress on the technique of frozen embryo transfer in sheep,illustrated selection of donors and receptors,superovulation,synchronization of estrus,embryo cryopreservation and embryo transplantation. Frozen embryo transfer in sheep is another breakthrough in the high-quality sheep raising,and this technique in China is in its infancy recommendation stage,but it will be comprehensively popularized in the future.

Factors influencing the outcome of embryo freezing and thawing program

Objective: To investigate the factors that might influence the success of an embryo freezing and thawing program. Method: The relationship between the pregnancy rate in 73 cycles of embryo freezing and thawing program and the following factors was analyzed: maternal age, E 2 level at the time of HCG trigger, embryo storage time, number of thawed embryos transferred, presence of sponsoring embryos and intact embryos. And the survival rate of thawed embryos with different morphology, cell stage and storage time was evaluated. Result: Transfer with three or more than three thawed embryos resulted in pregnancy rates of 38.5% and 35.7%, respectively, compared with 5.3% for transfer of fewer than three embryos. The presence of sponsoring embryos and intact embryos significantly increases pregnancy rate in embryo freezing and thawing program. No other factor examined had any effect on pregnancy outcome. The survival rate of good morphology embryos was higher than poor ones, but was not influenced by cell stage and storage time. Conclusion: Embryo morphology before freezing, number of thawed embryos transferred and the presence of intact embryos are important to the outcome of embryo freezing and thawing program.

Effect of Combinations of Sucrose and Cryoprotectants on the Survival of Catfish Embryos （Pangasidae hypophthamus）

Although cryopreservation of embryos has been used in most terrestrial animals, the application of this technique has not been succeeded for aquatic animals. In this study, the authors investigate the effect of different combinations of sucrose （SUC, C12H22OH） and cryoprotectants （CPAs） on the survival of the catfish embryos （Pangasidae hypophthalmus） at low temperatures （4, 0 and -20 ℃） for short-term storage. For this aim, embryos with somites and optic cups were exposed to different combinations of sucrose with methanol （SUC ＋ MeOH）, 1.2-propylene glycol （SUC ＋ PROH） and ethylene glycol （SUC ＋ EG） at four concentrations ratios： （1） 0.5 M SUC ＋ 0.5 M CPA; （2） 1 M SUC ＋ 0.5 M CPA; （3） 0.5 M SUC ＋ 1 M CPA; （4） 1 M SUC ＋ 1 M CPA for 40 min at 4, 0 and -20 ℃. Embryos kept in water at room temperature （RT）, 4, 0 and -20℃ were used as controls. The survival rate was expressed as a percentage of hatched embryos per total embryos treated. The results showed that the hatching rate declined significantly when embryos were stored in water at 0 ℃ and -20℃. For embryos at 0 ℃ storage, the highest survival rate （87.78%） was obtained with 1 M SUC ＋ 1 M MeOH combination while at -20 ℃, only embryos in the combined treatments of 0.5 M SUC ＋ 1 MEG and 0.5 M SUC ＋ 1 M PROH reached the hatching stage （40% and 83.33%, respectively）. In conclusion, the results showed that the catfish embryos are sensitive to sub-zero temperatures and the combined treatment of 0.5 M sucrose and 1 M propylene glycol can be used to protect catfish embryos from damages caused by low temperature （0 ℃ and -20 ℃）.

Effect of Plant AntifreezeProteins on Porcine Embryo to Cryopreservaton

This study was to research the cryopreservation effect of plant antifieeze proteins(AFPs) on day 7 porcine expanded and hatched blastocysts that were frozen in 1.5 M glycerol by conventional slow freezing method. The developmental rates of porcine embryos frozen with 0.5 mg/ml AFPs in freeze medium and cultured for 12 and 24 hours in vitro are 25% and 0%respectively. With the concentration of AFPs increased to 5 mg/ml, the corresponding values became 80% and 40%. The hatched rates for porcine embryos frozen with 0.5 mg/ml and 5 mg/ml of AFPs and cultured for 24 hours in vitro are 0% and 20% respectively..The developmental and hatched rate of the contnrol are all 0%(0/4). These results indicate that the survival rates of porcine expanded and hatched blastocyst can be improved by supplementing freeze medium with plant AFPs.

An update on primary ovarian insufficiency

Primary ovarian insufficiency(POI) occurs in about 1% of female population under the age of 40,leading to reproductive problems,an earlier encounter with menopausal symptoms,and complicated diseases.There are three presumable mechanisms involved in the development of POI,namely apoptosis acceleration,follicular maturation blocking and premature follicle activation,through the following studied causes:(i) chromosomal abnormalities or gene mutations:mostly involve X chromosome,such as FMR1 premutation;more and more potentially causal genes have been screened recently;(ii) metabolic disorders such as classic galactosaemia and 17-OH deficiency;(iii) autoimmune mediated ovarian damage:observed alone or with some certain autoimmune disorders and syndromes;but the specificity and sensitivity of antibodies towards ovary are still questionable;(iv) iatrogenic:radiotherapy or chemotherapy used in cancer treatment,as well as pelvic surgery with potential threat to ovaries' blood supply can directly damage ovarian function;(v) virus infection such as HIV and mumps;(vi) toxins and other environmental/lifestyle factors:cigarette smoking,toxins(e.g.,4-vinylcyclohexene diepoxide),and other environmental factors are associated with the development of POI.The etiology of a majority of POI cases is not identified,and is believed to be multifactorial.Strategies to POI include hormone replacement and infertility treatment.Assisted conception with donated oocytes has been proven to achieve pregnancy in POI women.Embryo cryopreservation,ovarian tissue cryopreservation and oocyte cryopreservation have been used to preserve ovarian reserve in women undergoing cancer treatments.

Epigenetic reprogramming of embryos derived from sperm frozen at-20℃

Cryopreservation of spermatozoa is a strategy that has been used to conserve the sperm of animal species and animal strains that are valuable for biomedical research. A simple method for preserving spermatozoa after application of intracytoplasmic sperm injection （ICSI） is much needed. It has been shown previously that spermatozoa frozen at -20~C can activate oocytes and support full-term embryo development. However, epigenetic reprogramming could be affected by the environment and by the in vitro manipulation of gametes. Here, we investigated embryo epigenetic reprogramming including DNA methylation and histone modification, in embryos derived from sperm preserved at -20~C without cryoprotectants. The results showed that alt- hough both fertilization and embryo developmental competence were decreased, the dynamic epigenetic reprogramming of embryos derived from frozen sperm was similar to the reprogramrning of embryos derived from fresh sperm. The results re- ported in this study indicate that sperm frozen without cryoprotectant is epigenetically safe for ICSI.