神经干细胞在PLGA、壳聚糖和明胶膜表面的生长规律

目的探索神经干细胞在PLGA、壳聚糖和明胶膜表面的生长规律,寻找适合中枢神经再生的支架材料.方法大鼠胚胎神经干细胞以105/mL密度分别种植于PLGA、壳聚糖和明胶膜表面,观察神经干细胞的生长、分化情况.结果接种后12h神经干细胞在壳聚糖膜表面呈团簇状贴附,在明胶膜表面24h贴附牢固;第2d起明胶膜表面贴附的神经干细胞周围见有突起的分化细胞;第3d壳聚糖膜表面贴附的神经干细胞周围也见有突起的分化细胞,壳聚糖膜部分溶解,明胶膜完全溶解,第5d分化细胞长满膜表面;观察期内PLGA膜表面无神经干细胞贴附,PLGA膜保持完整.结论神经干细胞不能在PLGA膜表面贴附和生长,在壳聚糖和明胶膜表面贴附和分化良好,壳聚糖比明胶更利于神经干细胞贴附,明胶比壳聚糖更利于神经干细胞分化.PLGA、壳聚糖和明胶都不宜单独作为生物支架材料和神经干细胞共同构建中枢神经工程化组织.     

肝脏组织工程纳米纤维支架材料的比较研究

探讨海藻酸钠、壳聚糖和PLGA纳米纤维支架的机械稳定性、生物相容性及细胞在其表面的生长规律,寻找合适的肝脏组织工程支架材料。用静电纺丝的方法分别制备海藻酸钠、壳聚糖和PLGA纳米纤维支架,观察材料的机械稳定性及肝细胞在材料表面的活性和生长情况。接种后0.5 h内,肝细胞在壳聚糖和海藻酸钠材料表面贴壁,生长良好。第二天起,肝细胞在壳聚糖表面逐渐聚集生长,形成聚集体,而在海藻酸钠材料表面无聚集。第三天后,海藻酸钠材料发生溶胀,纳米结构破坏,而壳聚糖纳米支架保持完好。在观察期间,PLGA材料表面一直没有肝细胞黏附。肝脏细胞不能在PLGA纳米材料表面黏附生长;壳聚糖具有良好的生物相容性,且肝细胞在壳聚糖纳米材料表面能形成球形聚集体;海藻酸钠生物相容性好,但机械稳定性差,容易降解,不能单独作为肝脏组织工程的纳米支架材料。     

壳聚糖材料在脊髓损伤后神经再生的研究与作用

背景：组织工程支架材料壳聚糖能复合多种种子细胞和神经因子,维持受损组织正常的解剖结构,防止胶质瘢痕挤压,对脊髓损伤后神经再生具有重要的意义。 目的：介绍壳聚糖材料在修复脊髓损伤后神经再生领域的研究现状。 方法：由第一作者检索1990至2012年 PubMed数据库、CNKI数据库及万方数据库有关壳聚糖材料特性、壳聚糖导管移植治疗脊髓损伤的相关文献。 结果与结论：壳聚糖具有良好的物理、化学性能,并且具有良好的生物相容性、生物降解性,免疫抗原性小和无毒性等特殊生物医学特性,与嗅鞘细胞、骨髓间充质干细胞及神经干细胞具有良好的亲和性。壳聚糖材料制备的神经导管、支架能在脊髓损伤后桥接神经断端,维持神经再生的正常解剖结构,提供种子细胞及细胞因子载体,为损伤后神经再生提供良好的微环境,但目前对于壳聚糖导管的研究仍不够全面,仍有很多问题待解决。     

壳聚糖改性聚醚醚酮表征及对MC3T3-E1细胞黏附、增殖的影响

背景：聚醚醚酮的生物惰性表面限制了其医学应用,如何提高聚醚醚酮的生物活性亟待解决。目的：分析壳聚糖生物活性涂层改性聚醚醚酮的表面特征及其对MC3T3-E1细胞增殖、黏附的影响。方法：取圆片状聚醚醚酮材料,依次进行NaBH4、3-氨丙基三乙氧基硅烷、戊二醛水溶液及壳聚糖溶液处理,获得壳聚糖生物活性涂层改性的聚醚醚酮材料。使用X射线光电子能谱、扫描电镜、原子力显微镜与全自动接触角测量仪观察化学处理前后聚醚醚酮材料的表面特征。将MC3T3-E1细胞分别接种于聚醚醚酮与壳聚糖改性聚醚醚酮材料表面,观察细胞的增殖与黏附情况。结果与结论：(1)X射线光电子能谱检测显示,聚醚醚酮材料仅含有C、O元素,壳聚糖改性聚醚醚酮材料含有C、O、N、Si元素;壳聚糖改性聚醚醚酮材料表面的接触角小于聚醚醚酮材料(P <0.05);(2)扫描电镜下可见,聚醚醚酮材料表面有明显的凹槽状起伏,壳聚糖改性聚醚醚酮材料表面存在壳聚糖分子,大小为1.0-2.0μm;原子力显微镜下可见,聚醚醚酮材料表面有较多的微小凹坑,大小约为0.1μm,壳聚糖改性聚醚醚酮材料表面的凹坑增大,大小为0.2-0.5μm,表面粗糙度大于聚醚...     

氧化石墨烯/壳聚糖复合涂层影响成骨细胞的生物学行为

背景：壳聚糖作为医用金属表面的涂层材料可以有效改善其生物学性能,但单纯壳聚糖存在自身生物活性与成骨诱导能力不足的问题;氧化石墨烯能够提高多种聚合物材料的机械性能和生物相容性,并具有促进成骨分化的作用,将两者结合得到的涂层材料可能具有更好的生物性能和成骨活性。目的：构建氧化石墨烯改性的壳聚糖复合涂层材料,分析涂层材料的表面形貌、化学组成和物理性质,并进一步分析涂层材料对成骨细胞增殖、黏附和成骨分化行为的影响。方法：使用3-氨丙基三乙氧基硅烷对钛片表面进行处理,在钛片表面形成硅烷基团,然后利用戊二醛使壳聚糖与硅烷基团形成交联,分别制备单纯壳聚糖涂层与氧化石墨烯/壳聚糖复合涂层。通过原子力显微镜、扫描电镜、傅里叶变换红外光谱仪、接触角测量系统表征涂层的表面形貌、化学结构及亲水性能。将大鼠成骨细胞直接接种于两种涂层材料表面,通过CCK-8实验、扫描电镜和半定量PCR分析材料对大鼠成骨细胞增殖、细胞铺展与成骨分化的影响。结果与结论：(1)通过原子力显微镜测得氧化石墨烯片层的厚度为2 nm左右;扫描电镜下可见,两种涂层表面均光滑致密,其中壳聚糖分子紧密排列,氧化石墨烯能够均匀分布于壳聚糖中,同时由...     

壳聚糖修饰丝素蛋白与人脂肪间充质干细胞体外构建组织工程脂肪

背景:在保留丝素蛋白原有优点的基础上,采用带正电荷的水溶性壳聚糖对其表面进行修饰,可改善细胞在支架材料上的黏附性。目的:验证壳聚糖表面修饰丝素蛋白支架材料与人脂肪间充质干细胞的生物相容性及两者体外构建组织工程脂肪的可行性。方法:将第3代人脂肪间充质干细胞悬液以1×107 L-1浓度接种于壳聚糖表面修饰丝素蛋白支架材料上作为实验组,以单纯的细胞悬液为对照组,MTT法检测细胞在支架材料上的黏附和增殖能力。将第3代人脂肪间充质干细胞悬液以1×109 L-1浓度接种于壳聚糖表面修饰丝素蛋白支架材料上,分别进行成脂诱导培养与高糖培养基常规培养,14 d后行细胞-支架复合物油红O染色与RT-PCR检测。结果与结论:人脂肪间充质干细胞在壳聚糖表面修饰丝素蛋白支架材料上黏附、增殖良好。成脂诱导14 d后,油红O染色显示壳聚糖修饰丝素蛋白支架材料上有大量脂肪细胞生成,且过氧化物酶增殖物活化受体γ2基因表达阳性。结果表明壳聚糖表面修饰丝素蛋白支架材料具有良好的体外生物相容性,与人脂肪间充质干细胞共培养可被成功诱导为成熟脂肪细胞。     

3D打印胶原/壳聚糖支架改善大鼠脊髓损伤后神经功能恢复

文题释义：壳聚糖：为一种天然多糖,是虾蟹等低等动物外壳的重要成分,具有一定的机械强度,并且具有良好的生物相容性和抗菌性,在生物工程领域具有较好的应用前景。 3D生物打印：是组织工程中最重要的技术之一。目前常用的三维生物打印方法包括喷墨打印、挤压生物打印和激光生物打印,选择好合适的材料后,在计算机指导下根据所选择的生物材料和细胞类型逐层准确地打印出所设计的结构。 背景：3D打印技术可以根据需求制备出满足脊髓植入形状、大小和表面形态要求的生物支架。 目的：观察3D打印胶原/壳聚糖支架对脊髓损伤大鼠神经功能恢复的影响。 方法：将胶原和壳聚糖按2∶1的质量比混合,采用冷冻干燥法制备普通胶原/壳聚糖支架,采用3D打印机制备3D打印胶原/壳聚糖支架,分别测量两种支架的孔隙率和弹性模量,电镜观察支架形态。将神经干细胞分别与3D打印胶原/壳聚糖支架、普通胶原/壳聚糖支架共培养,进行扫描电镜观察与CCK-8检测。将40只雌性SD大鼠(由中国人民解放军医学科学院军事科学院提供)随机分成4组：假手术组、脊髓损伤组、普通胶    原/壳聚糖支架组和3D打印胶原/壳聚糖支架组,后3组制作脊髓全横断损伤模型,普通胶原/壳聚糖支架组和3D打印胶原/壳聚糖支架组损伤处填充对应的支架材料,术后相应时间点进行后肢功能BBB评分、斜坡实验、神经电生理检测与磁共振平扫。实验方案经天津市神经创伤重点实验室伦理委员会批准。 结果与结论：①扫描电镜显示,3D打印胶原/壳聚糖支架具有互连的多孔结构,普通胶原/壳聚糖支架内部结构紊乱;②神经干细胞在3D打印胶原/壳聚糖支架表面生长良好,完全伸展,且3D打印胶原/壳聚糖支架表面神经干细胞的活性显著高于普通胶原/壳聚糖支架组(P < 0.05);③3D打印胶原/壳聚糖支架的孔隙率与弹性模量均高于普通胶原/壳聚糖支架组(P < 0.05);④3D打印胶原/壳聚糖支架组术后3-8周的BBB评分高于脊髓损伤组、普通胶原/壳聚糖支架组(P < 0.05),术后4,6,8周的斜坡实验角度大于脊髓损伤组、普通胶原/壳聚糖支架组(P < 0.05);⑤3D打印胶原/壳聚糖支架组术后8周的运动诱发电位振幅、体感诱发电位振幅大于脊髓损伤组与普通胶原/壳聚糖支架组(P < 0.05),运动诱发电位潜伏期、体感诱发电位潜伏期短于脊髓损伤组与普通胶原/壳聚糖支架组(P < 0.05);⑥磁共振平扫显示与脊髓损伤组及普通胶原/壳聚糖支架组比较,3D打印胶原/壳聚糖支架组损伤处具有较好的连续性与较多的神经纤维束通过;⑦结果表明,3D打印胶原/壳聚糖支架可促进脊髓损伤大鼠神经功能的修复。 ORCID: 0000-0001-5771-8222(史新宇) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

壳聚糖/聚乳酸羟基乙酸组织工程化神经植入犬体内的慢性生物相容性

背景：2个月以内短期生物相容性实验显示,壳聚糖、聚乳酸和聚羟基乙酸对大鼠外周神经均无毒性,可作为组织工程化神经材料。 目的：评价壳聚糖/聚乳酸羟基乙酸组织工程化神经植入Beagle犬体内6个月后的慢性生物相容性。 方法：在壳聚糖神经导管中插入聚乳酸羟基乙酸纤维制备成组织工程化神经,移植桥接Beagle犬坐骨神经50mm缺损,同时以Beagle犬50mm自体神经移植作为对照组。 结果与结论：植入壳聚糖/聚乳酸羟基乙酸组织工程化神经6个月后,Beagle犬精神、食欲、活动等一般情况良好,体质量增加与对照组相当;植入后2,4,6个月血液学和血清生化检测结果与对照组无明显差异;再生神经及其周边组织未出现变性、坏死,心、肝、脾、肺、肾等主要脏器大体解剖和组织切片未见异常。表明壳聚糖/聚乳酸羟基乙酸组织工程化神经植入Beagle犬体内6个月后慢性生物相容性良好。     

生物玻璃/壳聚糖三维多孔支架的抗感染性能和生物相容性研究

目的 研发制备生物玻璃/壳聚糖三维多孔支架(BG/CS),对其生物相容性及抗感染性能进行研究,阐明其抗感染作用的关键因素。方法 通过模板法制备多孔生物玻璃(BG)支架,注入壳聚糖乙酸,合成生物玻璃/壳聚糖多孔支架,此后以BG作为对照组,通过场发射扫描电镜(FESEM)观察各组材料的表面形貌和孔结构;接种Balb/c小鼠胚胎成纤维细胞(Balb/c 3T3 cells)于不同材料表面培养,分析其对细胞黏附及增殖的影响;各组支架材料分别与标准菌株ATCC 35984(表皮葡萄球菌)和ATCC 25923(金黄色葡萄球菌)共培养,以复合染料染色,在激光共聚焦显微镜(CLSM)下观察各组支架材料表面活菌和死菌的荧光强度;采用结晶紫染色法,定量分析材料表面细菌生物膜形成情况;进行细菌涂板并计数菌落(CFUs/cm2),测算抑菌效率。结果 BG/CS支架材料表面被覆一层壳聚糖,支架呈多孔结构,孔径较均一(200～400 m);材料细胞共培养4 h,BG/CS和BG表面的黏附细胞数量比较差异无统计学意义;共培养1 d,两组材料表面细胞均可正常黏附和铺展;第1～7 d的增殖过程中,各组材料表面细胞的增殖趋势接近,组间细胞增殖率比较差异无统计学意义;经过8 h细菌与材料共培养,CLSM下观测BG支架表面存在大量的细菌黏附(绿色荧光),BG/CS表面则显示出代表死亡细菌的红色荧光;生物膜定量实验显示在2～5 h,5～8 h,与BG组相比,BG/CS支架则明显抑制了生物膜的形成(P0.01);共培养12 h,与BG组相比,BG/CS组胰酶大豆琼脂平板(TSA)培养板表面细菌的单克隆菌落数明显较少,表现出较高的抑菌效率(P0.01)。结论 生物玻璃/壳聚糖三维多孔支架(BG/CS)具有较好的体外生物相容性和抗感染性能,有望作为一种应用于骨关节感染预防及治疗的骨修复填充材料。     

组织工程神经支架材料的临床应用

背景：神经损伤后没有自我修复的能力,因此,神经组织工程支架材料应用于神经修复、促进神经再生成为研究的热点。 目的：分析目前常用的神经组织工程支架材料的应用范围及效果。 方法：分别对胶原、壳聚糖、凝胶以及透明质酸与人工合成材料形成的聚合物用于神经损伤修复进行动物模型分析,应用免疫染色、生化检测等方法观察评估再生神经的结构和生理功能,确定不同神经组织工程支架材料的应用效果。 结果与结论：神经组织工程支架材料胶原、壳聚糖、凝胶、透明质酸以及人工合成材料均可以通过不同的方式用于损伤神经的再生修复,既可以联合细胞进行生物聚合,也可以联合神经片段移植形成损伤神经桥状联接导管,应用于动物模型实验均显示较好的治疗效果。     

壳聚糖和PHBHHx用作神经修复导管材料的研究

壳聚糖(Chitosan)和PHBHHx（羟基丁酸酯和羟基己酸酯共聚物）都是天然可降解材料。我们通过对这两种材料的亲水性、保持吸附蛋白有序结构的能力、胎鼠大脑皮层细胞在材料上生长情况以及两种材料的机械性能和后处理可加工性的研究，综合评价了它们作为神经修复导管材料的可行性。指出它们都有希望作为神经修复导管的材料。     

几丁糖与聚乳酸合成生物材料修复周围神经缺损

背景：单纯几丁糖材料制成的神经导管机械强度较差,易于塌陷,不利于再生神经的生长。 目的：观察几丁糖与聚乳酸复合物修复大鼠周围神经缺损的可行性。 方法：取30只SD大鼠,制作单侧坐骨神经缺损模型,随机均分为3组,分别采用自体神经、硅胶导管及几丁糖与聚乳酸复合导管修复神经缺损,修复后12周,观察桥接神经外观、表面粘连情况及有无神经瘤生成等,检测大鼠神经传导速度、动作电位波幅及潜伏期,苏木精-伊红染色观察坐骨神经桥接物中段神经再生轴突数量及再生神经横截面积,称量大鼠完整小腿三头肌湿质量。 结果与结论：修复后12周,3组再生神经均通过5 mm神经缺损间隙,硅胶管组形成神经瘤,其余两组均未出现神经瘤;自体神经组再生神经直径大于几丁糖-聚乳酸组、硅胶管组(P < 0.05),几丁糖-聚乳酸组再生神经直径大于硅胶管组(P < 0.05);几丁糖-聚乳酸组、自体神经组可见排列整齐的高密度再生轴突,再生轴突数量多于硅胶管组(P < 0.05),且神经传导速度、动作电位波幅、小腿三头肌湿质量显著大于硅胶管组(P < 0.05),潜伏期低于硅胶管组(P < 0.05)。表明几丁糖-聚乳酸复合导管可促进缺损周围神经的再生。  中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

Surface modification and characterization of chitosan film blended with poly-L-lysine

Biodegradable nerve guidance conduits (NGCs) represent a promising alternative to current clinical nerve repair procedures. Chitosan, a natural polysaccharide that has excellent biocompatibility and biodegradability, can be used as a nerve conduit material. The purpose of this work was to study the nerve cell affinity of chitosan modified by blending with different content of poly-L-lysine. PC12 cells culture was used to evaluate the nerve cell affinity of the chitosan-poly-L-lysine composite materials. The results showed that composite materials had significantly improved nerve cell affinity compared to chitosan as indicated by increased attachment, differentiation, and growth of nerve cells. The improved nerve cell affinity might be due to both the increased surface charge and hydrophilicity of composite materials. Composite material with 3 wt% poly-L-lysine content (PL-3) is an even better material in nerve cell affinity than collagen, suggesting that poly-L-lysine-blended chitosan is a promising candidate material for nerve regeneration.     

Chitosan tubes of varying degrees of acetylation for bridging peripheral nerve defects

Biosynthetic nerve grafts are desired as alternative to autologous nerve grafts in peripheral nerve reconstruction. Artificial nerve conduits still have their limitations and are not widely accepted in the clinical setting. Here we report an analysis of fine-tuned chitosan tubes used to reconstruct 10 mm nerve defects in the adult rat. The chitosan tubes displayed low, medium and high degrees of acetylation (DAI: ∼2%, DA: ∼5%, DAIII: ∼20%) and therefore different degradability and microenvironments for the regenerating nerve tissue. Short and long term investigations were performed demonstrating that the chitosan tubes allowed functional and morphological nerve regeneration similar to autologous nerve grafts. Irrespective of the DA growth factor regulation demonstrated to be the same as in controls. Analyses of stereological parameters as well as the immunological tissue response at the implantation site and in the regenerated nerves, revealed that DAI and DAIII chitosan tubes displayed some limitations in the support of axonal regeneration and a high speed of degradation accompanied with low mechanical stability, respectively. The chitosan tubes combine several pre-requisites for a clinical acceptance and DAII chitosan tubes have to be judged as the most supportive for peripheral nerve regeneration.     

Studies on nerve cell affinity of biodegradable modified chitosan films

Chitosan, a natural polysaccharide that has excellent biocompatibility and biodegradability,can be used as nerve conduit material. The purpose of this work was to study the ability of chitosan and some chitosan-derived materials to facilitate nerve cell attachment, differentiation and growth. The biomaterials studied were chitosan, poly-L-lysine-blended chitosan (CP), collagen-blended chitosan (CC) and albumin-blended chitosan (CA), with collagen control material. Culture of PC12 cells and fetal mouse cerebral cortex (FMCC) cells on these biomaterials was used to evaluate their nerve cell affinity. The composite materials, including CP, CC and CA, had significantly improved nerve cell affinity compared to chitosan, as established by increasing attachment, differentiation and growth of PC12 cells. FMCC cells could also grow better on composite materials than on chitosan. CP exhibited the best nerve cell affinity among these three types of composite material. CP is an even better material in promoting neurite outgrowth than collagen, a substrate that is widely used in tissue engineering, suggesting that CP is a promising candidate material for nerve regeneration.     

Studies on nerve cell affinity of biodegradable modified chitosan films

Chitosan, a natural polysaccharide that has excellent biocompatibility and biodegradability, can be used as nerve conduit material. The purpose of this work was to study the ability of chitosan and some chitosan-derived materials to facilitate nerve cell attachment, differentiation and growth. The biomaterials studied were chitosan, poly-L-lysine-blended chitosan (CP), collagen-blended chitosan (CC) and albumin-blended chitosan (CA), with collagen control material. Culture of PC12 cells and fetal mouse cerebral cortex (FMCC) cells on these biomaterials was used to evaluate their nerve cell affinity. The composite materials, including CP, CC and CA, had significantly improved nerve cell affinity compared to chitosan, as established by increasing attachment, differentiation and growth of PC12 cells. FMCC cells could also grow better on composite materials than on chitosan. CP exhibited the best nerve cell affinity among these three types of composite material. CP is an even better material in promoting neurite outgrowth than collagen, a substrate that is widely used in tissue engineering, suggesting that CP is a promising candidate material for nerve regeneration.     

Functional recoveries of sciatic nerve regeneration by combining chitosan-coated conduit and neurosphere cells induced from adipose-derived stem cells

Suboptimal repair occurs in a peripheral nerve gap, which can be partially restored by bridging the gap with various biosynthetic conduits or cell-based therapy. In this study, we developed a combination of chitosan coating approach to induce neurosphere cells from human adipose-derived stem cells (ASCs) on chitosan-coated plate and then applied these cells to the interior of a chitosan-coated silicone tube to bridge a 10-mm gap in a rat sciatic nerve. Myelin sheath degeneration and glial scar formation were discovered in the nerve bridged by the silicone conduit. By using a single treatment of chitosan-coated conduit or neurosphere cell therapy, the nerve gap was partially recovered after 6 weeks of surgery. Substantial improvements in nerve regeneration were achieved by combining neurosphere cells and chitosan-coated conduit based on the increase of myelinated axons density and myelin thickness, gastrocnemius muscle weight and muscle fiber diameter, and step and stride lengths from gait analysis. High expressions of interleukin-1β and leukotriene B4 receptor 1 in the intra-neural scarring caused by using silicone conduits revealed that the inflammatory mechanism can be inhibited when the conduit is coated with chitosan. This study demonstrated that the chitosan-coated surface performs multiple functions that can be used to induce neurosphere cells from ASCs and to facilitate nerve regeneration in combination with a cells-assisted coated conduit.     

Studies on nerve cell affinity of chitosan-derived materials

Reparation of the central nervous system (CNS) is important because when it is impaired its recovery is difficult and concomitant malfunction of other parts of body occurs. In our previous studies, chitosan was found to be a good material supporting nerve repair. The purpose of this article was to study the ability of chitosan and some chitosan-derived materials to facilitate the growth of nerve cells. Those materials were chitosan, glutaraldehyde-crosslinked chitosan, glutaraldehyde-crosslinked chitosan-gelatin conjugate, a chitosan-gelatin mixture, chitosan coated with polylysine (CAP), and a chitosan-polylysine mixture (CPL). Gelatin and polylysine were used as controls. After nerve cells (gliosarcoma cells and normal cerebral cells) were grown on those materials, their attachment, spread, and growth were observed. The adsorption of some extracellular matrix molecules such as laminin and fibronectin on the materials and the role the molecules play in nerve cell attachment and spreading were also studied by enzyme-linked immunosorbent assay and MTT method. We found that both CAP and CPL have excellent nerve cell affinity, defined as the ability to promote nerve cell to grow and function normally. Those two materials may be promising for the repair of the nervous system. Materials precoated with laminin, fibronectin, and serum were analyzed for their nerve cell affinity. Results suggest that after being precoated with laminin and fibronectin solution or serum, all material have better nerve cell affinity.     

修复周围神经缺损的组织工程研究

取有限的自体可牺牲的神经组织剥去外膜及束膜制成粗品雪旺氏细胞，并保留其中剖分基质，与２％壳聚糖凝胶制成混材料，加入外源性神经生长因子，注江表管内用以套接修复大鼠坐同有神经１００ｍｍ之缺损，术后１２周神经电生理测试及再生神经横面图像分析形态计量提示。     

Study on physical properties and nerve cell affinity of composite films from chitosan and gelatin solutions

A series of chitosan-gelatin composite films was prepared by varying the ratio of constituents. FT-IR and X-ray analysis showed good compatibility between these two biopolymers. Differential scanning calorimetry (DSC) analysis indicated that the water take-up of chitosan film increased when blended with gelatin. Composite film exhibited a lower Young's modulus and a higher percentage of elongation-at-break compared with chitosan film, especially in wet state. All composite films were hydrophilic materials with water contact angles ranging from 55 degrees to 65 degrees. The results obtained from ELISA indicated the adsorption amount of fibronectin on composite films was much higher than on chitosan film. PC12 cells culture was used to evaluate the nerve cell affinity of materials. The cells cultured on the composite film with 60wt% gelatin differentiated more rapidly and extended longer neurites than on chitosan film. The results suggest that the soft and elastic complex of chitosan and gelatin, which has better nerve cell affinity compared to chitosan, is a promising candidate biomaterial for nerve regeneration.