甲壳素涂层并预置引导纤维神经导管的实验研究

目的探讨甲壳素涂层并预置引导纤维神经导管修复周围神经缺损的效果。方法成年雌性SD大鼠24只，无菌条件下切断双侧坐骨神经，制成14mm的大鼠坐骨神经缺损模型。根据不同修复材料随机分为4组，每组6只。A组：甲壳素涂层并预置引导纤维的聚乳酸聚羟基乙酸共聚物（polyglycolic-lacticacid，PGLA）神经导管；B组：甲壳素涂层的PGLA神经导管；C组：单纯PGLA神经导管；D组：自体神经移植作为对照。术后4周和12周行大体观察、肌电图检查、S-100免疫组织化学染色和组织学观察，图像分析评价修复效果。结果术后4周A、B及C组观察到神经导管中有新生轴索通过，再生神经发育不成熟；D组近段有髓神经纤维均匀疏散分布，远段未见明显再生神经束形成。术后12周各组再生神经已通过神经导管长入远端，肌电图、S100免疫组织化学染色和图像分析结果表明A组再生神经轴突数量及再生神经质量优于B、C组，差异有统计学意义（P〈0．05）。D组移植神经轴突直径、髓鞘厚度、纤维密度与A、B及C组比较，差异有统计学意义（P〈0．05），但D组近段神经髓鞘部分空泡样变性及脱髓鞘改变，远段再生神经束形成少。结论甲壳素涂层并预置引导纤维的神经导管能有效修复周围神经缺损。     

壳聚糖神经导管修复犬胫神经缺损的实验研究

目的:探讨壳聚糖涂层并预置引导纤维神经导管修复周围神经缺损的效果。方法:18条杂交犬,平均分成3组,无菌条件下切断左侧胫神经,制成25mm的犬胫神经缺损模型。采用壳聚糖涂层并预置引导纤维的聚乳酸和聚羟基乙酸共聚物(PLGA)神经导管作为实验组A组,以单纯PLGA神经导管为B组,自体神经移植组为C组作对照,每组6条犬。术后12周后通过一般观察,肌电图检查,HE染色和S-100免疫组化观察,再生神经图像分析等评价修复的效果。结果:术后12周各组再生神经已通过神经导管长入远端,肌电图,HE染色和图像分析结果表明A组再生神经轴突数量及再生神经质量优于B组(P<0.05);C组优于A、B组。结论:壳聚糖涂层并预置引导纤维的神经导管能有效修复周围神经缺损。     

神经导管联合自体变性肌桥修复大鼠周围神经缺损的实验研究

目的探讨PLGA神经导管联合化学萃取的自体骨骼肌肌桥,修复大鼠坐骨神经缺损的可能性。方法SD大鼠45只,建立大鼠左侧坐骨神经缺损模型。随机分为3组．分别采用自体神经（A组）、PLGA神经导管（B组）和PLGA神经导管联合化学萃取自体骨骼肌肌桥（C组）．来修复神经缺损。术后通过大体观察、坐骨神经功能指数测定、腓肠肌湿质量恢复率测定、组织学观察和图像分析对比等,检测神经缺损修复情况。结果神经导管联合化学萃取自体骨骼肌肌桥能促进坐骨神经再生．各项指标均优于单纯神经导管移植．但是效果略差于自体神经移植。结论PLGA神经导管联合化学萃取自体骨骼肌肌桥．对大鼠坐骨神经缺损具有良好的桥梁作用和促神经生长的作用。     

血管化人工神经导管修复大鼠坐骨神经缺损的实验研究

目的 研究血管化人工神经导管修复SD大鼠坐骨神经缺损的效果.方法 将成年雌性SD大鼠18只,制成14 mm的大鼠坐骨神经缺损模型,随机分为3组,用不同的材料修复缺损.A组:自体神经修复组;B组:普通PGLA神经导管修复组;C组:血管化人工神经导管修复组.术后行大体观察;术后6、12周行肌电图和再生神经轴突检测,评价神经修复效果.结果 术后6、12周,C组与B组相比,神经传导速度快,动作电位振幅大,再生神经轴突数量多且质量高,差异有显著的统计学意义(P<0.05).结论 血管化人工神经导管能促进神经再生,有效地修复长段神经缺损.     

雪旺细胞复合PLGA修复兔面神经缺损的实验研究

目的：探讨高分子可吸收材料PLGA(聚乳酸-聚羟基乙酸共聚物)复合体体外培养的雪旺细胞修复兔面神经缺损的可行性。方法：取胎兔坐骨神经体外增殖培养雪旺细胞后，复合于PLGA，用于修复兔面神经1cm缺损，以单用导管修复组为对照。评价修复效果。结果：术后8周及16周的组织学及电生理结果表明，导管加细胞修复效果优于单纯导管修复。结论：导管复合雪旺细胞是一种较好的外周神经缺损修复手段。     

脉冲等离子体涂层神经导管修复周围神经缺损实验研究

目的:探讨经脉冲等离子体涂层并固定睫状神经营养因子(CNTF)的聚羟基乙酸和聚乳酸共聚物(PGLA)神经导管修复周围神经缺损的效果.方法:应用脉冲等离子方法对PGLA膜片或神经导管表面进行处理,然后固定CNTF.该膜片表面种植人胚胎视神经细胞,经处理的神经导管修复SD大鼠坐骨神经1.5 cm缺损.观察人胚胎视神经细胞在经处理的膜片上生长情况,并用电生理和轴突计数法评价经处理的神经导管内神经再生质量.设立未固定CNTF的PGLA膜片组和未经过脉冲等离子体涂层的神经导管组作为对照组比较.结果:在经处理的PGLA膜片上,人胚胎视神经细胞生长较对照组密集,且发现有轴突延伸相接现象.经处理的PGLA修复大鼠坐骨神经缺损,在1个月和3个月时,均发现神经导管内神经传导速度和再生神经轴突均明显大于对照组(P＜0.05).结论:经脉冲等离子体涂层并固定睫状神经营养因子(CNTF)的PGLA神经导管可能通过CNTF的接触诱导和持续缓释作用,促进周围神经再生.     

联合运用冻融法和化学法去细胞同种异体神经修复兔面神经缺损

目的：通过对去细胞同种异体神经处理方法的改进,找出一种修复兔面神经缺损的理想替代材料。方法：取24只兔子,将兔左侧面神经上颊支切断以造成面神经缺损1.0cm的模型,根据修复方法不同,随机分成2组：实验组为联合运用冻融法和化学法去细胞同种异体神经修复组,对照组为自体面神倒置修复组,每组12只。术后3个月行大体观察、神经电生理检测、有髓神经纤维计数以及电镜观察,采用SPSS17.0软件包对数据进行t检验,对面神经恢复情况进行综合评价。结果：两组兔子均存活,切口愈合良好,兔面形基本对称;实验组与对照组左侧面神经上颊支传导速度分别为（55.74±10.56）m/s及（61.34±9.72）m/s,差异无显著性（P〉0.05）;实验组与对照组移植体远端吻合口邻近4.0mm段有髓神经纤维数量分别为（18173.62±918.38）n/mm2及（18601.21±982.31）n/mm2,差异亦无显著性（P〉0.05）;电镜检查结果相似。结论：联合运用冻融法和化学法去细胞同种异体神经能满意修复一定长度的面神经缺损,可以作为自体神经的一种有效替代物。     

睫状神经营养因子涂层的聚羟基乙酸聚乳酸神经导管修复犬胫神经缺损

目的 探讨应用脉冲等离子体方法涂层睫状神经营养因子（CNTF）的聚羟基乙酸聚乳酸（PGLA）神经导管修复犬胫冲经缺损的疗效。方法 18只杂交犬．每只犬左后肢制成胫神经2．5cm缺损模型，随机分别应用三种方法修复。A组：应用脉冲等离子体方法涂层CNTF的PGLA神经导管；B组：单纯PGLA神经咩管；C组：自体神经。应用苏木精-伊红和Masson染色、S-100免疫组化染色、神经电生理及神经轴突计数方法评价神经再生效果。同时动态记录犬行走步态变化，实验观察期3个月。结果 神经导管血管化良好且大部分降解吸收，再生神经均已通过所有神经导管。A组与C组的神经传导速度和神经轴突计数差异无统计学意义（P〉0．05），而A组和C组的数据均优于B组（P〈0．05）。A组和C组的犬基本恢复正常行走步态，而B组犬仍有跛行。结论 脉冲等离子体方法涂层CNTF的PGLA神经导管能有效修复犬2．5cm胫神经缺损，取得与自体神经相近的效果。     

几丁糖/聚乙烯醇神经导管修复猕猴周围神经缺损的实验研究

目的探讨应用几丁糖/聚乙烯醇神经导管修复猕猴周围神经缺损的效果。方法成年猕猴12只,雄性5只,雌性7只,体重3.26～5.35 kg。实验动物随机分成A、B、C 3组,制备左侧桡神经2 cm缺损模型,分别用几丁糖/聚乙烯醇神经导管移植、神经切除旷置和自体神经逆行原位移植处理。实验动物右侧为正常对照。术后8个月,行大体观察、组织学观测及电生理检测评价神经再生效果。结果术后8个月,A组再生神经通过神经导管长入神经缺损的远侧端,再生神经粘连较轻;B组未见再生神经通过神经缺损断端;C组移植神经与周围组织粘连较重。A、C组可检测出肌电图表现,B组未检测到。A、C组间波幅差异无统计学意义(P>0.05),但均不及正常对照侧,差异有统计学意义(P<0.05);C组潜伏期和神经传导速度优于A组,但均不及正常对照侧,差异均有统计学意义(P<0.05)。有髓神经纤维密度:A、C组较正常对照侧小,差异有统计学意义(P<0.05);A、C组间差异无统计学意义(P>0.05)。有髓神经纤维直径和髓鞘厚度:C组优于A组,但均不及正常对照侧,差异均有统计学意义(P<0.05)。结论几丁糖/聚乙烯醇神经导管具有促进猕猴神经轴突再生的作用,有望成为自体神经替代材料应用于周围神经缺损修复。     

自组装多肽与神经生长因子导管修复兔周围神经缺损

[目的]探索自组装多肽凝胶复合神经生长因子(NGF)的神经导管修复周围神经损伤的可行性及效果。[方法]以静电纺丝技术制备单纯聚乳酸-羟基乙酸(PLGA)和PLGA复合NGF的纳米纤维复合神经导管,制备"异亮氨酸-赖氨酸-缬氨酸-丙氨酸-缬氨酸"(IKVAV)顺序的自组装多肽凝胶。选取新西兰大白兔72只,制备兔坐骨神经10 mm缺损模型。按随机数字法分为4组,每组18只,分别给予以下处理:A组自体神经移植,B组单纯PLGA神经导管+NGF桥接,C组单纯PLGA神经导管+IKVAV多肽凝胶+NGF桥接、D组复合NGF的PLGA导管+IKVAV多肽凝胶桥接。术后1、2、3个月行电生理检测、大体观察、小腿三头肌湿重恢复率测量和组织学检查。[结果]术后复合NGF导管逐渐吸水膨胀并降解,周围组织未见明显炎性反应,无神经卡压。术后1个月,再生神经已通过缺损,但直径细小,随着时间延长逐渐增粗。各组间比较发现,D组神经再生效果接近A组,各项指标优于B组(P0.05),部分指标优于C组(P0.05)。D组和A组之间比较,差异无统计学意义(P0.05),但小腿三头肌湿重恢复率较A组稍差。[结论]自组装多肽凝胶联合复合神经生长因子的神经导管具有良好的组织相容性,能够有效促进神经生长,效果接近自体神经移植。     

Sciatic nerve repair with tissue engineered nerve: Olfactory ensheathing cells seeded poly(lactic-co-glygolic acid) conduit in an animal model

Background and Aim:

Synthetic nerve conduits have been sought for repair of nerve defects as the autologous nerve grafts causes donor site morbidity and possess other drawbacks. Many strategies have been investigated to improve nerve regeneration through synthetic nerve guided conduits. Olfactory ensheathing cells (OECs) that share both Schwann cell and astrocytic characteristics have been shown to promote axonal regeneration after transplantation. The present study was driven by the hypothesis that tissue-engineered poly(lactic-co-glycolic acid) (PLGA) seeded with OECs would improve peripheral nerve regeneration in a long sciatic nerve defect.

Materials and Methods:

Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM) examination and immunohistochemical analysis were performed at the end of the study.

Results:

Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 ΁ 0.4 m/s at week 2 to 27.3 ΁ 5.7 m/s at week 6 post-implantation (P < 0.0001). Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix.

Conclusion:

Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model.     

甲壳质生物套管膜与许旺细胞生物相容性的实验研究

目的 研究甲壳质生物套管膜与许旺细胞的生物相容性。方法 将甲壳质生物套管膜与许旺细胞共同培养，观察、检测细胞在膜上和膜外的生长情况。结果 在套管膜周围细胞形态和数量与对照培养孔内细胞无明显差别。套管膜上有细胞贴附生长。鼠尾胶原包被的套管膜上细胞数量较单纯套管膜上细胞数量多。结论 甲壳质生物套管膜与许旺细胞有良好的生物相容性，经过鼠尾胶原包被后更有利于细胞贴附生长。     

聚乳酸-聚羟基乙酸神经导管和骨髓间充质干细胞构建组织工程神经

[目的]用聚乳酸-聚羟基乙酸共聚物(poly lactide-co-glycolide acid,PLGA)为原料制备新型神经导管,同时对兔骨髓间充质干细胞与PLGA构建组织工程神经的可行性进行观察.[方法]以聚乳酸-聚羟基乙酸共聚物和壳寡糖为原料,采用静电纺丝工艺制备中空的PLGA神经导管.通过扫描电镜观察材料的微观结构,排水法测定材料的孔隙率.将兔的骨髓间充质干细胞(BMSCs)分离培养后与导管共培养,扫描电镜观察细胞在材料上的生长粘附情况,MTT方法检测细胞在材料上的增殖活性.[结果]PLGA神经导管管壁具有疏松多孔结构,管壁纤维直径为18 μm左右,孔隙率为85.4%±1.6%,MTT结果显示导管无细胞毒性.兔骨髓间充质干细胞在导管表面生长良好.[结论]PLGA神经导管具有良好的孔隙率,生物相容性好,是构建组织工程神经的良好材料.     

Large-area irradiated low-level laser effect in a biodegradable nerve guide conduit on neural regeneration of peripheral nerve injury in rats

This study used a biodegradable composite containing genipin-cross-linked gelatin annexed with β-tricalcium phosphate ceramic particles (genipin-gelatin-tricalcium phosphate, GGT), developed in a previous study, as a nerve guide conduit. The aim of this study was to analyse the influence of a large-area irradiated aluminium-gallium-indium phosphide (AlGaInP) diode laser (660 nm) on the neural regeneration of the transected sciatic nerve after bridging the GGT nerve guide conduit in rats. The animals were divided into two groups: group 1 comprised sham-irradiated controls and group 2 rats underwent low-level laser (LLL) therapy. A compact multi-cluster laser system with 20 AlGaInP laser diodes (output power, 50 mW) was applied transcutaneously to the injured peripheral nerve immediately after closing the wound, which was repeated daily for 5 min for 21 consecutive days. Eight weeks after implantation, walking track analysis showed a significantly higher sciatic function index (SFI) score (P < 0.05) and better toe spreading development in the laser-treated group than in the sham-irradiated control group. For electrophysiological measurement, both the mean peak amplitude and nerve conduction velocity of compound muscle action potentials (CMAPs) were higher in the laser-treated group than in the sham-irradiated group. The two groups were found to be significantly different during the experimental period (P < 0.005). Histomorphometric assessments revealed that the qualitative observation and quantitative analysis of the regenerated nerve tissue in the laser-treated group were superior to those of the sham-irradiated group. Thus, the motor functional, electrophysiologic and histomorphometric assessments demonstrate that LLL therapy can accelerate neural repair of the corresponding transected peripheral nerve after bridging the GGT nerve guide conduit in rats.     

碱性成纤维细胞生长因子结合静脉套接修复正中神经缺损

目的 探讨碱性成纤维细胞生长因子（bFGF）结合静脉套接修复周围神经缺损的效果.方法 8例4cm以内正中神经缺损,取自体静脉套接并对断面进行处理,静脉内注入碱性成纤维细胞生长因子0.5ml,术后检查Tinel征、神经肌电图,受损靶肌肉注射0.2mlbFGF.结果 随访10月～2年,3例神经缺损1～1.9cm,神经功能评定为优.2例神经缺损2～2.9cm,神经功能评定为优.2例神经缺损3.0～3.5cm,神经功能评定为优1良1.1例神经缺损3.6～4.0cm,神经功能评定为良.所有病例神经再生速度大于2mm/天.结论 碱性成纤维细胞生长因子（BFGF）结合静脉套接是修复神经缺损的有效方法,能明显促进神经再生.     

RGD多肽接枝聚复合导管桥接神经缺损的实验研究

Objective To investigate the effect of RGD peptide conjugated poly[ LA-(Glc-Lys) ]/βTCP/PLA nerve conduit for bridging peripheral nerve regeneration defect. Methods Forty-five male Wister rots were randomly divided into 3 groups, with 15 rats each. A 10 mm defect was created in the right sciatic nerve. In group A the gap was bridged by PLA tube. In group B RGD peptide conjugated poly[ LA-(Glc-Lys) ]/β-TCP/PLA nerve conduit was used to repair the defect. Autologous nerve graft was done in group C which served as control. Twelve weeks postoperatively nerve regeneration was evaluated by gross observation,electrophysiology, muscle weight and muscle morphometry of triceps surae, and ultrastructure of the regenerating nerve. Results Twelve weeks after the operation, nerve conduction velocity and muscle weight recovery of group B were better than those of group A. The differences were statistically significant( P < 0.05). There was no significant difference between group B and group C ( P > 0. 05). The results of histology and ultrastructure showed that nerve regeneration in group B and group C was significantly superior to that in group A.Conclusion RGD peptide conjugated poly[LA-(Glc-Lys)]/β-TCP/PLA conduit can achieve similar results in repairing sciatic nerve defect to that of autogentic nerve graft. It may be an ideal material to repair nerve defect.     

RGD多肽接枝聚复合导管桥接神经缺损的实验研究

Objective To investigate the effect of RGD peptide conjugated poly[ LA-(Glc-Lys) ]/βTCP/PLA nerve conduit for bridging peripheral nerve regeneration defect. Methods Forty-five male Wister rots were randomly divided into 3 groups, with 15 rats each. A 10 mm defect was created in the right sciatic nerve. In group A the gap was bridged by PLA tube. In group B RGD peptide conjugated poly[ LA-(Glc-Lys) ]/β-TCP/PLA nerve conduit was used to repair the defect. Autologous nerve graft was done in group C which served as control. Twelve weeks postoperatively nerve regeneration was evaluated by gross observation,electrophysiology, muscle weight and muscle morphometry of triceps surae, and ultrastructure of the regenerating nerve. Results Twelve weeks after the operation, nerve conduction velocity and muscle weight recovery of group B were better than those of group A. The differences were statistically significant( P < 0.05). There was no significant difference between group B and group C ( P > 0. 05). The results of histology and ultrastructure showed that nerve regeneration in group B and group C was significantly superior to that in group A.Conclusion RGD peptide conjugated poly[LA-(Glc-Lys)]/β-TCP/PLA conduit can achieve similar results in repairing sciatic nerve defect to that of autogentic nerve graft. It may be an ideal material to repair nerve defect.     

RGD多肽接枝聚复合导管桥接神经缺损的实验研究

Objective To investigate the effect of RGD peptide conjugated poly[ LA-(Glc-Lys) ]/βTCP/PLA nerve conduit for bridging peripheral nerve regeneration defect. Methods Forty-five male Wister rots were randomly divided into 3 groups, with 15 rats each. A 10 mm defect was created in the right sciatic nerve. In group A the gap was bridged by PLA tube. In group B RGD peptide conjugated poly[ LA-(Glc-Lys) ]/β-TCP/PLA nerve conduit was used to repair the defect. Autologous nerve graft was done in group C which served as control. Twelve weeks postoperatively nerve regeneration was evaluated by gross observation,electrophysiology, muscle weight and muscle morphometry of triceps surae, and ultrastructure of the regenerating nerve. Results Twelve weeks after the operation, nerve conduction velocity and muscle weight recovery of group B were better than those of group A. The differences were statistically significant( P < 0.05). There was no significant difference between group B and group C ( P > 0. 05). The results of histology and ultrastructure showed that nerve regeneration in group B and group C was significantly superior to that in group A.Conclusion RGD peptide conjugated poly[LA-(Glc-Lys)]/β-TCP/PLA conduit can achieve similar results in repairing sciatic nerve defect to that of autogentic nerve graft. It may be an ideal material to repair nerve defect.