猪卵巢体外保存温度对卵母细胞染色质构型和成熟能力的影响

Most porcine oocytes used in studies on embryo biotechnology and the in vitro production of embryos are currently obtained from the ovaries of slaughtered gilts. The duration and temperature during ovary transportation and handling might, therefore, affect the recovery of culturable COCs, chromatin configuration and developmental competence of oocytes. The effects of ovary storage temperature on chromatin configuration and in vitro maturation of porcine oocytes were examined in this study. Ovaries collected from a slaughterhouse were stored in vitro for 8 h under different temperatures. The results showed that more culturable COCs were isolated from the ovares stored at 39℃ than that from ovaries stored at 31℃ or 20℃ and before storage. Thirty-one centidegree was the best storage temperature in terms of cumulus expansion, nuclear maturation and morphology of the first polar body after in vitro maturation culture. The ability of cumulus expansion was completely lost in COCs derived from ovaries stored at 39℃ for 8 hours. Ovary storage （at both 31℃ and at 20℃ ） increased the proportion of oocytes with the GVc configuration in which chromatin condensed into a single big clump at the nucleolus and the functional significance of this configuration needs further investigations [ Acta Zoologica Sinica 51 （5）： 919 923, 2005].     

真菌防御素plectasin研究进展

抗生素耐受现象日益严重,迫切需要研发新型抗菌药物。Plectasin是第一例报道的真菌防御素,其抗菌谱窄,仅对革兰氏阳性菌具有强大的杀菌活性,对其进行结构改造可进一步提高其抗菌作用特异性。Plectasin抗菌机制明晰,作用于细胞壁合成。其药物代谢动力学研究较为透彻,同时可在体外高产量表达且活性更高。这些研究为其应用提供了理论基础。综上,plectasin具有极大的临床应用潜力。