神经干细胞和骨髓间充质干细胞移植治疗脊髓损伤效果与机制对比

目的比较神经干细胞和骨髓间充质干细胞移植治疗脊髓损伤的机制及实验效果。方法选择40只Wistar成年大鼠做脊髓半横切模型,随机分为神经干细胞注射组,骨髓间充质干细胞注射组,磷酸盐缓冲液注射组和假手术组,每组10只。对比4组大鼠移植后的运动功能和脊髓损伤的修复情况。结果神经干细胞注射组各个时间点的BBB评分明显高于骨髓间充质干细胞注射组,且2组BBB评分明显高于磷酸盐缓冲液注射组,差异具有统计学意义(P0.05);神经干细胞和骨髓间充质干细胞移植后的第8周,MRI显示空洞明显缩小,信号强度正常,能看到完整的脊髓,脊髓切片中能看到被标记的NSCs及BMSCs。结论脊髓损伤大鼠通过静脉注射NSCs和BMSCs均能改善运动功能,但NSCs治疗效果更为明显,应将两种方法结合起来,进一步提高治疗效果。     

分区式脊髓导管联合骨髓基质干细胞修复脊髓横断损伤模型大鼠

BACKGROUND: There is a high morbidity after spinal cord injury, and the therapeutic strategy is limited to early surgical intervention, medication and post-treatment exercise that only can improve the motor function slightly. However, there is no effective cure method.OBJECTIVE: To study the effect of partition-type spinal cord catheter combined with bone marrow stromal stem cells on T₈ spinal cord transection damage in rats.METHODS: Fifty rats were randomized into five groups (n=10 per group): group I, T₈ spinal cord transection    (5 mm) was made in rats with no treatment; group II, the partition-type tube was inserted into the injured site after modeling; group III, partition-type tube combined with bone marrow stromal stem cells was implanted into the injured site after modeling; group IV, partition-type tube combined with polyglycolic acid fibers was implanted into the injured site after modeling; group V, partition-type tube combined with bone marrow stromal stem cells and polyglycolic acid fibers was implanted into the injured site after modeling. RESULTS AND CONCLUSION: At 2 and 12 weeks postoperatively, Basso, Beattie and Bresnahan scores were significantly higher in the groups III and IV than the groups I, II, IV (P < 0.05). At 12 weeks postoperatively, the latency of motor evoked potential below the injury plane was significantly decreased in group V compared with groups I, II, III, IV (P < 0.05). Immunohistochemical results displayed that in the groups III and V, regenerated nerve fibers grew positively and arranged orderly among the tubes, and there was no obvious winding phenomenon. Under transmission electron microscopy, a certain number of myelinated nerve fibers were found as bridges among groups. These findings indicate that the partition-type chitosan tube combined with bone marrow stromal stem cells has a good connection with the injured spinal cord a good connection to restore part of electrophysiological properties, accelerate the axon regeneration, recover the motor function, thereby providing a new direction for the treatment of spinal cord injury.  中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

Let-7d通过靶向调控Rhotekin基因抑制骨肉瘤细胞的增殖、迁移和侵袭

目的 探讨let-7d在骨肉瘤组织中的表达,并研究let-7d及其靶基因对人骨肉瘤细胞U2OS增殖、迁移和侵袭的影响。方法 收集2010年至2015年于我科行手术切除的25例骨肉瘤患者的肿瘤组织和癌旁组织（距肿瘤组织边缘>5 cm）,并用qPCR检测let-7d的表达情况。构建稳定过表达let-7d的U2OS细胞,用qPCR验证let-7d过表达情况,以转染pCDH空病毒载体的U2OS细胞作为对照组细胞,并分别采用CCK-8实验、划痕实验和Transwell实验检测过表达let-7d对U2OS细胞增殖、迁移和侵袭能力的影响。通过微RNA靶基因预测软件和双荧光素酶实验明确let-7d的下游靶基因,检测过表达let-7d的U2OS细胞中靶基因的表达水平,并通过小干扰RNA技术研究抑制靶基因表达对U2OS细胞增殖、迁移和侵袭的影响。结果 骨肉瘤组织中let-7d表达水平低于癌旁组织（P<0.01）。与人成骨细胞hFOB1.19相比,U2OS细胞中let-7d表达水平下调（P<0.01）。与对照组相比,过表达let-7d能抑制U2OS细胞的增殖、迁移和侵袭（P均<0.05）。微RNA靶基因预测软件和双荧光素酶实验结果显示,Rhotekin（RTKN）基因是let-7d的直接靶基因,且过表达let-7d导致U2OS细胞中RTKN mRNA表达水平较对照组降低（P<0.01）。干扰RTKN表达能抑制U2OS细胞增殖、迁移和侵袭（P均<0.05）。结论 Let-7d通过靶向调控RTKN抑制骨肉瘤细胞的增殖、迁移和侵袭,可作为骨肉瘤治疗一个新的靶点。