周围神经端侧吻合研究进展

目前临床上常用的神经吻合方法仍为神经端端吻合，但在临床实际工作中经常遇到神经远端完好，而近端已经撕脱或严重损害，不能用常规的端端吻合方法进行神经的重建。虽然神经移植能重建损伤的神经，但将损伤另外一条神经，并牺牲其支配区的功能。寻找一种即能达到修复损伤...     

自体骨髓单个核细胞移植治疗糖尿病下肢周围神经病变

背景：有研究表明移植骨髓单个核细胞治疗糖尿病下肢神经病变动物模型,通过在组织内能促进血管再生和增加血管生成因子及神经营养因子能改善临床症状。                             目的：观察自体骨髓单个核细胞移植治疗糖尿病下肢周围神经病变的临床效果。 方法：30例糖尿病下肢闭塞症患者60条下肢,按治疗方式的不同分为2组：自体骨髓单个核细胞移植的治疗组和对侧下肢非自体骨髓单个核细胞移植的对照组,各30条下肢。 结果与结论：移植4周后,治疗组总有效率高于对照组(P < 0.05)。两组治疗后神经病变自主症状问卷神经病变主觉症状问卷评分均较治疗前明显降低,治疗组评分降低更明显(P < 0.01),治疗组胫神经和腓总神经感觉和运动神经传导速度均较对照组快(P < 0.01),患者未出现并发症和不良反应。说明自体骨髓单个核细胞移植治疗糖尿病下肢周围神经病变的临床效果较好。     

合成可生物降解神经导管修复损伤周围神经：生物相容性良好

背景：临床对周围神经损伤进行修复治疗的时候,可以利用自体神经进行治疗或者利用不同材质的神经导管进行治疗。 目的：探索合成可生物降解材料神经导管在周围神经损伤修复中的应用效果。 方法：48只新西兰大白兔,随机等分为3组,自体神经移植组、硅胶导管组和可降解神经导管组。各组动物切除10 mm坐骨神经,构建坐骨神经缺损动物模型,并分别利用自体神经、硅胶导管以及可降解神经导管进行坐骨神经修复。 结果与结论：造模后3周,硅胶导管组兔运动神经传导效果、小腿三头肌肌肉湿质量恢复率比自体神经移植组差,但可降解神经导管组兔运动神经传导效果、小腿三头肌肌肉湿质量恢复率与自体神经移植组接近。造模后12周时,自体神经移植组中存在大量呈均匀排列的有髓神经纤维,可降解神经导管组中可见大量分布不均匀的再生有髓神经纤维,而硅胶导管组中存在少量呈不均匀排列的髓神经纤维。表明合成可生物降解材料神经导管在周围神经损伤修复中可以获得与自体神经较为接近的良好效果。  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     

合成材料神经导管与自体神经移植修复周围神经缺损的比较

背景：生物可降解材料制成的神经导管可在体内降解,避免出现的神经卡压等问题,因而受到越来越多的关注。 目的：比较自体神经移植与3种合成可生物降解材料神经导管在修复周围神经损伤的效果差异。 方法：通过电生理学检测,形态学观察等神经恢复效果评价方法,对比分析近年来常用的胶原神经导管、DL-乳酸-ε-己内酯神经导管、聚乙醇酸神经导管与自体神经移植修复周围神经缺损的效果。 结果与结论：虽然神经导管与自体神经移植相比在理论上有其优势的一面,但不同合成材料的神经导管之间在神经功能恢复中存在明显差异性,DL-乳酸-ε-己内酯神经导管修复效果与自体神经移植无明显差异,是较为理想的神经导管材料,聚乙醇酸神经导管因自身的因素影响其降解性能,在3种神经导管中的修复周围神经损伤效果最差,胶原神经导管需要交联剂改善其机械性能,其修复周围神经损伤效果居于前两者之间,因此,这3种神经导管在神经功能再生方面还有潜在的缺陷,不能完全替代自体神经移植,而且3者之间的性价比,还缺少足够的大样本长期随机对照实验结果来验证,还需要进一步的实验观察。     

冷冻保存胎兔周围神经异体移植

目的 :探讨胚胎兔周围神经经冷冻保存后 ,同种异体移植修复周围神经缺损的作用。方法 :以采用两步冷冻方法制备冷冻保存的胎兔坐骨神经 (维持温度值 - 4 0℃ )为供体 ,移植桥接成年兔腓总神经缺损区 ,并与自体神经移植、新鲜异体神经移植、空白缺损比较 ,16周后作再生神经电生理检测、神经断面图像分析及透射电镜观察。结果 :胎神经移植组神经再生效果不如自体神经好 ,但优于新鲜异体神经组。结论 :冷冻保存胎神经移植桥接周围神经缺损 ,可以促进和引到轴突再生 ,有可能代替自体神经移植     

组织工程神经修复周围神经缺损研究及其展望

长段周围神经缺损的修复和功能重建仍然是手外科、显微外科临床的难题之一,目前常采用的自体神经移植属于"拆东墙补西墙"式的修复方法,存在供体神经支配区永久性失神经功能障碍及供移植神经来源局限等缺点.因此,临床期盼一种能替代自体神经移植的有效治疗方法,而组织工程技术的发展促进了构建神经移植替代物修复周围神经缺损的研究与应用[1].     

冻干辐照异体神经的制备及保存

冻干辐照异体神经的制备及保存李祥鹏，常洪贤，王殿柱，张习高，彭东，沙建慧（空军医学高等专科学校吉林１３２０１１）由于创伤、肿瘤等引起的周围神经缺损，临床多采用显微外科技术行自体神经移植修复。因自体神经移植，无排斥反应，效果肯定。但自体神经移植也有其不...     

膈神经移位治疗臂丛损伤的研究进展

臂丛根性撕脱伤是临床常见的损伤,其发病率高,致残严重,给社会生产带来严重影响。臂丛损伤早期以保守治疗为主,20世纪初开始引入手术治疗,并先后经历了损伤切除直接缝合、新鲜同种神经移植和自体神经移植三个阶段,但效果欠佳。后又有人采用多功能重建手术以改善屈肘功能。70年代     

组织工程修复周围神经损伤的研究进展

临床上常见的周围神经缺损一直是国内外学者亟待解决的难题.目前周围神经缺损的治疗方法 主要是依靠自体神经移植,但自体神经移植是"拆东墙补西墙"的方法 ,因此探索修复周围神经缺损的新方法 ,具有重人现实意义,组织工程学研究为解决这一问题提供了新的思路.种子细胞与导管支架制成的复合体是构建组织.工程的核心,本文就将种子细胞、导管支架的应用研究做一综述.     

干细胞移植治疗脊髓损伤的研究进展

背景：干细胞移植作为治疗脊髓损伤最具前景的方法,已经在大量的动物实验和临床试验中得到证实。 目的：综述干细胞移植治疗脊髓损伤的相关研究进展。 方法：应用计算机检索2006-01/2010-12中国知网、Medline数据库相关文章,中文检索词“干细胞,脊髓损伤,细胞移植”,英文检索词“stem cells,spinal cord injury,cells transplantation”,共检索到文献494篇,最终纳入符合标准的文献24篇。 结果与结论：研究发现,移植的干细胞可以在脊髓内迁移、分化为神经元并分泌神经营养物质,促进神经组织的修复,改善神经功能。胚胎干细胞最早用于治疗脊髓损伤,但潜在的致瘤性等成为其临床应用的障碍;神经干细胞理论上是治疗脊髓损伤的首选干细胞,由于分离纯化技术要求严格,费用昂贵等使其在研究中进展缓慢;骨髓间充质干细胞来源丰富、取材方便,可行自体移植,避开了伦理学和移植后排斥等问题,目前被认为是一种理想的自体干细胞移植来源。随着细胞联合移植、基因修饰及组织工程支架移植治疗脊髓损伤的研究不断取得进展,许旺细胞、嗅鞘细胞的应用范围和治疗效果也得到提升。     

Biomedical engineering strategies for peripheral nerve repair: surgical applications, state of the art, and future challenges

Damage to the peripheral nervous system is surprisingly common and occurs primarily from trauma or a complication of surgery. Although recovery of nerve function occurs in many mild injuries, outcomes are often unsatisfactory following severe trauma. Nerve repair and regeneration presents unique clinical challenges and opportunities, and substantial contributions can be made through the informed application of biomedical engineering strategies. This article reviews the clinical presentations and classification of nerve injuries, in addition to the state of the art for surgical decision-making and repair strategies. This discussion presents specific challenges that must be addressed to realistically improve the treatment of nerve injuries and promote widespread recovery. In particular, nerve defects a few centimeters in length use a sensory nerve autograft as the standard technique; however, this approach is limited by the availability of donor nerve and comorbidity associated with additional surgery. Moreover, we currently have an inadequate ability to noninvasively assess the degree of nerve injury and to track axonal regeneration. As a result, wait-and-see surgical decisions can lead to undesirable and less successful "delayed" repair procedures. In this fight for time, degeneration of the distal nerve support structure and target progresses, ultimately blunting complete functional recovery. Thus, the most pressing challenges in peripheral nerve repair include the development of tissue-engineered nerve grafts that match or exceed the performance of autografts, the ability to noninvasively assess nerve damage and track axonal regeneration, and approaches to maintain the efficacy of the distal pathway and targets during the regenerative process. Biomedical engineering strategies can address these issues to substantially contribute at both the basic and applied levels, improving surgical management and functional recovery following severe peripheral nerve injury.     

Sural nerve defects after nerve biopsy or nerve transfer as a sensory regeneration model for peripheral nerve conduit implantation

Nerve repair after injury can be effectively accomplished by direct suture approximation of the proximal and distal segments. This is more successful if coadaptation can be achieved without tension. Currently, the gold standard repair of larger deficits is the transplantation of an autologous sensory sural nerve graft. However, a significant disadvantage of this technique is the inevitable donor morbidity (sensory loss, neuroma and scar formation) after harvesting of the sural nerve. Moreover, limitation of autologous donor nerve length and fixed diameter of the available sural nerve are major drawbacks of current autograft treatment. Another approach that was introduced for nerve repair is the implantation of alloplastic nerve tubes made of, for example, poly-l-lactide. In these, nerve stumps of the transected nerves are surgically bridged using the biosynthetic conduit. A number of experimental studies, primarily in rodents, indicate axonal regeneration and remyelination after implantation of various conduits. However, only limited clinical studies with conduit implantation have been performed in acute peripheral nerve injuries particularly on digital nerves. Clinical transfer of animal studies, which can be carefully calibrated for site and extent of injury, to humans is difficult to interpret due to the intrinsic variability in human nerve injuries. This prevents effective quantification of improvement and induces bias in the study. Therefore, standardization of lesion/repair in human studies is warranted.     

Peripheral nerve injury,scarring, and recovery

ABSTRACT

Peripheral nerve injuries (PNI) resulting from trauma can be severe and permanently debilitating. Despite the armamentarium of meticulous microsurgical repair techniques that includes direct repair, grafting of defects with autograft nerve, and grafting with cadaveric allografts, approximately one-third of all PNI demonstrate incomplete recovery with poor restoration of function. This may include total loss or incomplete recovery of motor and/or sensory function, chronic pain, muscle atrophy, and profound weakness, which can result in lifelong morbidity. Much of this impaired nerve healing can be attributed to perineural scarring and fibrosis at the site of injury and repair. To date, this challenging clinical problem has not been adequately addressed. In this review, we summarize the existing literature surrounding biological aspects of perineural fibrosis following PNI, detail current strategies to limit nerve scarring, present our own work developing reliable nerve injury models in animal studies, and discuss potential future studies which may ultimately lead to new therapeutic strategies.     

Repairing injured peripheral nerves: Bridging the gap

Peripheral nerve injuries that induce gaps larger than 1-2 cm require bridging strategies for repair. Autologous nerve grafts are still the gold standard for such interventions, although alternative treatments, as well as treatments to improve the therapeutic efficacy of autologous nerve grafting are generating increasing interest. Investigations are still mostly experimental, although some clinical studies have been undertaken. In this review, we aim to describe the developments in bridging technology which aim to replace the autograft. A multi-disciplinary approach is of utmost importance to develop and optimise treatments of the most challenging peripheral nerve injuries.     

Assessment of processed human amniotic membrane as a protective barrier in rat model of sciatic nerve injury

Following nerve injury, scar formation is thought to be a considerable impediment to axonal regeneration at the nerve injury site. Nerve wrapping can protect the regenerating axons, and human amniotic membrane (HAM) derived from human placenta is an effective material for that purpose. The impact of nerve wrapping with HAM on functional recovery after nerve injuries, especially after autograft repair of long gap lesions, has not been comprehensively investigated. In the current study, we investigated whether the application of HAM as a nerve wrap to a 10mm segment of transected and repaired nerve would reduce scar formation and permit better axonal regeneration and/or functional recovery in rats. The outcome was assessed with morphological and functional measures. We found that nerves wrapped with HAM had significantly fewer adhesions and less scar formation than controls. Although the final outcome, both functionally and morphologically, was not significantly improved by wrapping the nerve with HAM, the observed decrease in adhesions and scar formation might help the nerve retain its mobility and thus prevent traction injury and ischemia, which are caused by nerve tethering to the adjacent tissue during the healing process.     

The effect of intraluminal contact mediated guidance signals on axonal mismatch during peripheral nerve repair

The current microsurgical gold standard for repairing long gap nerve injuries is the autograft. Autograft provides a protective environment for repair and a natural internal architecture, which is essential for regeneration. Current clinically approved hollow nerve guidance conduits allow provision of this protective environment; however they fail to provide an essential internal architecture to the regenerating nerve. In the present study both structured and unstructured intraluminal collagen fibres are investigated to assess their ability to enhance conduit mediated nerve repair. This study presents a direct comparison of both structured and unstructured fibres in?vivo. The addition of intraluminal guidance structures was shown to significantly decrease axonal dispersion within the conduit and reduced axonal mismatch of distal nerve targets (p?相似文献   

人工组织神经移植物修复狗缺损坐骨神经后腓肠肌的形态观察

目的 了解复合型医用可降解材料制成的人工组织神经移植物辅加神经再生素修复狗坐骨神经缺损后，腓肠肌的形态变化。方法 将人工组织神经移植物连接在狗的坐骨神经缺损30mm处。以自体神经桥接和神经缺损的狗为对照组Ⅰ和Ⅱ。术后6个月时取腓肠肌进行称重、特殊染色和组织化学染色，显微镜下了解腓肠肌的形态变化并进行图像定量分析，同时了解肌纤维的超微结构变化。结果 术后6个月，实验组腓肠肌的萎缩形态指标变化均轻于对照组Ⅱ，而与对照组Ⅰ相似。结论 经人工组织神经移植物修复缺损的坐骨神经后，使腓肠肌又重新获得神经支配，肌肉萎缩明显减轻。     

复合他克莫司聚乳酸-乙醇酸缓释导管修复大鼠胫神经缺损

背景：虽然单纯聚乳酸-乙醇酸导管修复大鼠神经缺损可部分恢复大鼠神经功能,但神经直径、再生纤维数量、髓鞘成熟度及功能恢复上均较自体神经移植差。 目的：观察复合他克莫司的聚乳酸-乙醇酸缓释导管修复大鼠胫神经缺损的可行性。 方法：制作SD大鼠右侧胫神经缺损模型,随机分为3组,分别植入自体胫神经、单纯聚乳酸-乙醇酸导管及复合他克莫司的聚乳酸-乙醇酸缓释导管修复。植入后3,6,12周行坐骨神经功能指数检查、电生理检查、组织学观测、腓肠肌湿质量测量。 结果与结论：植入后第6,12周复合他克莫司的聚乳酸-乙醇酸缓释导管组、自体胫神经组坐骨神经功能指数检查、电生理检查、组织学观测、腓肠肌湿质量测量结果优于单纯聚乳酸-乙醇酸导管组(P < 0.05),自体胫神经组、复合他克莫司的聚乳酸-乙醇酸缓释导管组比较差异无显著性意义。说明复合他克莫司的聚乳酸-乙醇酸缓释导管桥接修复大鼠胫神经缺损可明显促进断端神经的再生,在晚期功能恢复上取得接近自体神经移植的效果。 关键词：聚乳酸-乙醇酸;他克莫司;神经导管;大鼠;坐骨神经 doi:10.3969/j.issn.1673-8225.2012.12.003     

组织工程化神经修复周围神经创伤的应用

背景：近年来,随着生物工程技术以及组织工程化神经的发展给周围神经缺损的治疗带来了新的希望,已逐渐成为研究的焦点。 目的：从种子细胞、生物材料以及构建周围神经组织技术3个方面综述组织工程方法修复周围神经损伤的新进展。 方法：由第一作者在2013年7月应用计算机检索PubMed 数据库及CNKI 数据库,英文关键词为“tissue engineering,peripheral nerves,nerve injuries,stem cells,schwann cells,scaffold,growth factor”,中文关键词为“组织工程,周围神经,神经损伤,干细胞,许旺细胞,支架,生长因子”。选择内容与神经组织工程、周围神经损伤修复相关的文章,同一领域文献则选择近期发表或发表在权威杂志文章,共纳入63篇文献。 结果与结论：现阶段组织工程方法修复周围神经损伤的研究虽已取得很大进展,但大多停留于实验探索阶段。将组织工程神经应用于临床尚存下列问题亟待解决：①种子细胞来源及伦理。②细胞扩增后移植的免疫排斥。③移植细胞稳定性问题及致瘤性。④神经支架材料的降解速度、最佳孔隙率、导管厚度、形状等。⑤体外神经构建后移植修复时机。⑥各种神经生物因子的局部释放与调控等等。随着科技的发展,期待上述问题的解决,从而使得众多临床神经损伤患者受益。     

The use of keratin biomaterials derived from human hair for the promotion of rapid regeneration of peripheral nerves

The management of trauma-associated nerve defects is difficult because of the absence of autologous donor motor or sensory nerves. Pre-clinical development and clinical experience has shown that damaged nerves can be surgically repaired using a tubular conduit interposed across the defect. Acceptable patient outcomes are achieved so long as the gap distance does not exceed a few centimeters. Although research in animals has demonstrated that nerve repair can be facilitated across slightly larger gaps by introducing a biomaterial filler into the conduit lumen, these biomaterials are not typically "neuroinductive" (i.e. capable of acting directly on regenerative cells to enhance nerve tissue formation beyond clinical limits). Moreover, their use does not often result in functional recovery equivalent to nerve autograft, the clinical gold standard. Here we show that a biomaterial gel made from the proteins found in human hair can mediate a robust nerve regeneration response, in part through activation of Schwann cells. In vitro, keratins extracted from human hair enhance the activity of Schwann cells by a chemotactic mechanism, increase their attachment and proliferation, and up-regulate expression of important genes. Moreover, these characteristics translate to improved functional nerve recovery in an animal model. These results suggest that a biomaterial derived from human hair keratins is neuroinductive and can facilitate an outcome comparable to autograft in a nerve injury model.