Two-dimensional crystallization and preliminary electron crystallographic result of partially purified Fo from porcine mitochondria

After removal of cytoplasmic sector F1 from submitochondrial particles of FoF1-ATP synthase complex with guanidine hydrochloride, the transmembrane sector Fo was specifically extracted from the stripped membranes in the presence of detergent CHAPS and partially purified.Two-dimensional crystals were produced by the reconstitution of the partially purified Fo into asolectin and microdialysis. The obtained crystals are able to diffract to 2 nm. The projection map of the negatively stained crystal shows that the crystal has p4212 symmetry, lattice constant, a = b = 14.4nm. A unit cell contains four Fo molecules.     

人自体血清支持脐血源HSCs和MSCs共培养研究

考察使用cytodex-3微载体共培养人脐带血(UCB)来源的造血干细胞(HSCs)和间充质干细胞(MSCs)的可行性,并评价其应用于未来临床治疗中的可能性.考虑到临床应用的安全性要求,尝试采用采集于UCB的人自体血清(HAS)取代目前广泛使用的胎牛血清(FBS),以期在体外共培养后可同时获得UCB-HSCs和UCB-MSCs.由于MSCs贴附的cytodex-3载体与悬浮的HSCs之间的密度差异,在共培养后自由沉降分离这两种不同类型的干细胞将会十分容易.为优化培养条件,评估了用不同含量的HAS(2.8%、5.6%、8.3%和11.1%)对UCB-MSCs和UCB-HSCs扩增的影响.结果表明,5.6%HAS培养UCB-HSCs最优,扩增倍数达(1.88±0.33)倍,且同时对UCB-MSCs的扩增亦无很大影响.因此,共培养条件下的HAS最佳含量约为5.6%.所研发的共培养体系可为临床应用提供扩增的UCB-HSCs和UCB-MSCs.     

高糖诱导人脐血间充质干细胞向胰岛样细胞分化

目的:探讨脐血间充质干细胞向胰岛样细胞分化的潜能.方法:分离脐血有核细胞,将其置于MesencultTM培养基中进行培养,并利用贴壁法进行纯化、扩增.扩增后的脐血间充质干细胞用含体积分数5%胎牛血清的H-DMEM持续诱导.采用胰岛素免疫荧光染色对诱导后的细胞进行鉴定,定量检测胰岛素分泌水平及其对葡萄糖刺激的反应性.结果:诱导后,细胞形态发生明显变化,变圆而且聚集成团;细胞的胰岛素免疫荧光染色为阳性;而且细胞能分泌少量胰岛素,并对糖刺激具有反应性.结论:在高糖环境中,脐血间充质干细胞具有向胰岛样细胞分化的潜能.