为提高纳米纤维神经移植物的接触引导,设计了一种含有取向纳米纤维束的"芯鞘"型神经移植物,它利用静电纺高取向纳米纤维膜,两次卷绕形成"芯"和"鞘",最后通过静电纺丝喷覆而成.利用扫描电镜观察并表征了纤维及其移植物形态,测试了力学性能,将此移植物用于大鼠10 mm坐骨神经缺损,术后两月通过体外刺激和组织学观察了修复效果.结果表明:通过调整静电纺收集转辊转速可获得高取向聚乳酸纳米纤维,纳米纤维膜工程应力和伸长率达到(49.32±14.83)MPa和17.71%±0.06%,利用该膜构建的神经移植物缝合强力达到(1.18±0.40)N/针,能支持与保护神经再生,移植两月后,大鼠能够感知热与外力刺激,组织学观察发现,有神经纤维和血旺细胞长入神经移植物,证明了该构建技术的可行性,并有可能为神经修复提供一种新的移植材料.%To promote contact guidance,we constructed a novel nerve regeneration graft with'core-shell'structure.The aligned nanofibers membrane was collected using electrospinning technology and then rolled twice to form nanofibers bundle 'core ' and 'shell '. The morphologies of nanofibers were observed using SEM and their alignment was characterized. The tensile and suture strength were also tested by a micro-mechanical tester.The results showed that desirable alignment could be obtained by adjusting rotation speed.Along the fiber axial direction,strength of aligned PLA nanofibers membrane reached (49.32±14.83) MPa,the elongation was17.71%±0.06%,which could protect and support nervous system tissue regeneration. The suture strength was more than adequate for suturing during implantation (1.18±0.40)N/needle.Two months after transplantation,rats could sense heat and external stimulation,histological observation found that nerve fibers and Schwann cells infiltrated into the constructs from both proximal and distal nerve stumps.These results proved the feasibility of the construction technology.The new kind of graft may be a promising substitute for nerve regeneration.
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