The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Yumin Yang - One of the best experts on this subject based on the ideXlab platform.
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bridging peripheral Nerve defects with a tissue engineered Nerve Graft composed of an in vitro cultured Nerve equivalent and a silk fibroin based scaffold
Biomaterials, 2012Co-Authors: Xin Tang, Chengbin Xue, Yaxian Wang, Fei Ding, Yumin YangAbstract:Tissue engineered Nerve Grafts are considered as a promising alternative to autologous Nerve Grafts used for peripheral Nerve repair. The differences between these two types of Nerve Grafts are mainly in the regenerative microenvironment established by them. To construct ideal tissue engineered Nerve Grafts, it is therefore required to develop a better way to introduce biochemical cues into a neural scaffold, as compared to single or combined use of support cells and growth factors. Here, we used a co-culture system of dorsal root ganglia and Schwann cells to create an in vitro formed Nerve equivalent, which was introduced into a silk fibroin-based scaffold to furnish a tissue engineered Nerve Graft (TENG). At 4- and 12- weeks after the TENG was implanted to bridge a 10-mm-long sciatic Nerve defect in rats, histological and functional assessments as well as Western blot analysis were performed to evaluate the influences of the TENG on peripheral Nerve regeneration. We found that at an early stage of Nerve regeneration, the TENG significantly accelerated axonal growth, and up-regulated expressions of N-cadherin and PMP22. Twelve weeks after Nerve Grafting, the TENG produced a further improved outcome of Nerve regeneration and functional recovery, which was more close to that of the autologous Nerve Graft than that of the silk fibroin-based scaffold. The introduction of an in vitro cultured Nerve equivalent into a scaffold might contribute to establishing a native-like microenvironment for Nerve regeneration.
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chitosan polyglycolic acid Nerve Grafts for axon regeneration from prolonged axotomized neurons to chronically denervated segments
Biomaterials, 2009Co-Authors: Haishan Jiao, Yumin Yang, Xue Chen, Yi Li, Xiaosong Gu, Xiaodong WangAbstract:Peripheral Nerve regeneration for long-term delayed injuries is usually unsatisfied. Here we attempted to use a chitosan/polyglycolic acid (PGA) artificial Nerve Graft to bridge a long-term delayed 10-mm defect in SD rats based on the previous studies on the Graft used for immediate repair of 30-mm-long dog sciatic Nerve defects and for clinical treatment of a 35-mm-long median Nerve defect at elbow of a human patient. In this study, for experimental groups, the rat sciatic Nerve had been transected leaving a 10-mm defect, which was maintained for 3 or 6 months before implantation with the chitosan/PGA artificial Nerve Graft. The animals non-Grafted or Grafted with autoGraft served as negative or positive control group. In experiment groups, Nerve regeneration with functional recovery was achieved as measured by electrophysiological and histological techniques, although differences in the quantity and the quality of the regenerated Nerve were observed between the 3- and 6-month delayed subgroups. The results showed that: (1) a few denervated Schwann cells survived and sustained their ability to myelinate axons at least 6 months, and (2) the atrophic denervated muscle could be reinnervated by regenerated axons through new muscle-Nerve connections. These observations provide the possibility of guiding regenerated axons from survived axotomized neurons to distal Nerve stump by the chitosan/PGA artificial Nerve Graft.
Alvaro Cabello - One of the best experts on this subject based on the ideXlab platform.
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facial reanimation with gracilis muscle transfer neurotized to cross facial Nerve Graft versus masseteric Nerve a comparative study using the facial clima evaluating system
Plastic and Reconstructive Surgery, 2013Co-Authors: Bernardo Hontanilla, Diego Marre, Alvaro CabelloAbstract:Background Longstanding unilateral facial paralysis is best addressed with microneurovascular muscle transplantation. Neurotization can be obtained from the cross-facial or the masseter Nerve. The authors present a quantitative comparison of both procedures using the FACIAL CLIMA system. Methods Forty-seven patients with complete unilateral facial paralysis underwent reanimation with a free gracilis transplant neurotized to either a cross-facial Nerve Graft (group I, n=20) or to the ipsilateral masseteric Nerve (group II, n=27). Commissural displacement and commissural contraction velocity were measured using the FACIAL CLIMA system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using the independent samples t test. Mean percentage of recovery of both parameters were compared between the groups using the independent samples t test. Results Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I (p=0.001 and p=0.014, respectively) but not in group II. Intergroup comparisons showed that both commissural displacement and commissural contraction velocity were higher in group II, with significant differences for commissural displacement (p=0.048). Mean percentage of recovery of both parameters was higher in group II, with significant differences for commissural displacement (p=0.042). Conclusions Free gracilis muscle transfer neurotized by the masseteric Nerve is a reliable technique for reanimation of longstanding facial paralysis. Compared with cross-facial Nerve Graft neurotization, this technique provides better symmetry and a higher degree of recovery. Clinical question/level of evidence Therapeutic, III.
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facial reanimation with gracilis muscle transfer neurotized to cross facial Nerve Graft versus masseteric Nerve a comparative study using the facial clima evaluating system
Plastic and Reconstructive Surgery, 2013Co-Authors: Bernardo Hontanilla, Diego Marre, Alvaro CabelloAbstract:BACKGROUND: Longstanding unilateral facial paralysis is best addressed with microneurovascular muscle transplantation. Neurotization can be obtained from the cross-facial or the masseter Nerve. The authors present a quantitative comparison of both procedures using the FACIAL CLIMA system. METHODS: Forty-seven patients with complete unilateral facial paralysis underwent reanimation with a free gracilis transplant neurotized to either a cross-facial Nerve Graft (group I, n=20) or to the ipsilateral masseteric Nerve (group II, n=27). Commissural displacement and commissural contraction velocity were measured using the FACIAL CLIMA system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using the independent samples t test. Mean percentage of recovery of both parameters were compared between the groups using the independent samples t test. RESULTS: Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I (p=0.001 and p=0.014, respectively) but not in group II. Intergroup comparisons showed that both commissural displacement and commissural contraction velocity were higher in group II, with significant differences for commissural displacement (p=0.048). Mean percentage of recovery of both parameters was higher in group II, with significant differences for commissural displacement (p=0.042). CONCLUSIONS: Free gracilis muscle transfer neurotized by the masseteric Nerve is a reliable technique for reanimation of longstanding facial paralysis. Compared with cross-facial Nerve Graft neurotization, this technique provides better symmetry and a higher degree of recovery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.
Yu Wang - One of the best experts on this subject based on the ideXlab platform.
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A novel tissue engineered Nerve Graft constructed with autologous vein and Nerve microtissue repairs a long-segment sciatic Nerve defect.
Neural regeneration research, 2021Co-Authors: Jing Wang, Yaqiong Zhu, Yu Wang, Yue-xiang Wang, Xiao-qing Cheng, Qi QuanAbstract:Veins are easy to obtain, have low immunogenicity, and induce a relatively weak inflammatory response. Therefore, veins have the potential to be used as conduits for Nerve regeneration. However, because of the presence of venous valves and the great elasticity of the venous wall, the vein is not conducive to Nerve regeneration. In this study, a novel tissue engineered Nerve Graft was constructed by combining normal dissected Nerve microtissue with an autologous vein Graft for repairing 10-mm peripheral Nerve defects in rats. Compared with rats given the vein Graft alone, rats given the tissue engineered Nerve Graft had an improved sciatic static index, and a higher amplitude and shorter latency of compound muscle action potentials. Furthermore, rats implanted with the microtissue Graft had a higher density and thickness of myelinated Nerve fibers and reduced gastrocnemius muscle atrophy compared with rats implanted with the vein alone. However, the tissue engineered Nerve Graft had a lower ability to repair the defect than autogenous Nerve transplantation. In summary, although the tissue engineered Nerve Graft constructed with autologous vein and Nerve microtissue is not as effective as autologous Nerve transplantation for repairing long-segment sciatic Nerve defects, it may nonetheless have therapeutic potential for the clinical repair of long sciatic Nerve defects. This study was approved by the Experimental Animal Ethics Committee of Chinese PLA General Hospital (approval No. 2016-x9-07) on September 7, 2016.
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improvement in Nerve regeneration through a decellularized Nerve Graft by supplementation with bone marrow stromal cells in fibrin
Cell Transplantation, 2014Co-Authors: Zhe Zhao, Yu Wang, Jiang Peng, Zhiwu Ren, Li Zhang, Quanyi GuoAbstract:Acellular Nerve Grafting is often inferior as well as an inadequate alternative to autoGrafting for the repair of long gaps in peripheral Nerves. Moreover, the injection method is not perfect. During the injection of cells, the syringe can destroy the acellular Nerve structure and the limited accumulation of seed cells. To resolve this problem, we constructed a Nerve Graft by acellular Nerve Grafting. Bone marrow-mesenchymal stromal cells (BM-MSCs) were affixed with fibrin glue and injected inside or around the Graft, which was then used to repair a 15-mm Nerve defect in rats. The acellular Nerve Graft maintained its structure and composition, and its tensile strength was decreased, as determined by two-photon microscopy and a tensile testing device. In vitro, MSCs embedded in fibrin glue survived and secreted growth factors such as Nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). We repaired 15-mm Sprague-Dawley rat sciatic Nerve defects using this Nerve Graft construction, and MSCs injected around the Graft helped improve Nerve regeneration and functional recovery of peripheral Nerve lesions as determined by functional analysis and histology. Therefore, we conclude that supplying MSCs in fibrin glue around acellular Nerves is successful in maintaining the Nerve structure and can support Nerve regeneration similar to the direct injection of MSCs into the acellular Nerve for long Nerve defects but may avoid destroying the Nerve Graft. The technique is simple and is another option for stem cell transplantation.
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repair of Nerve defect with acellular Nerve Graft supplemented by bone marrow stromal cells in mice
Microsurgery, 2011Co-Authors: Zhe Zhao, Yu Wang, Jiang Peng, Zhiwu Ren, Shengfeng Zhan, Yan Liu, Bin Zhao, Qing Zhao, Li Zhang, Quanyi GuoAbstract:The acellular Nerve Graft that can provide internal structure and extracellular matrix components of the Nerve is an alternative for repair of peripheral Nerve defects. However, results of the acellular Nerve Grafting for Nerve repair still remain inconsistent. This study aimed to investigate if supplementing bone marrow mesenchymal stromal cells (MSCs) could improve the results of Nerve repair with the acellular Nerve Graft in a 10-mm sciatic Nerve defect model in mice. Eighteen mice were divided into three groups (n = 6 for each group) for Nerve repairs with the Nerve autoGraft, the acellular Nerve Graft, and the acellular Nerve Graft by supplemented with MSCs (5 × 105) fibrin glue around the Graft. The mouse static sciatic index was evaluated by walking-track testing every 2 weeks. The weight preservation of the triceps surae muscles and histomorphometric assessment of triceps surae muscles and repaired Nerves were examined at week 8. The results showed that the Nerve repair by the Nerve autoGrafting obtained the best functional recovery of limb. The Nerve repair with the acellular Nerve Graft supplemented with MSCs achieved better functional recovery and higher axon number than that with the acellular Nerve Graft alone at week 8 postoperatively. The results indicated that supplementing MSCs might help to improve Nerve regeneration and functional recovery in repair of the Nerve defect with the acellular Nerve Graft. © 2011 Wiley-Liss, Inc. Microsurgery, 2011.
Quanyi Guo - One of the best experts on this subject based on the ideXlab platform.
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improvement in Nerve regeneration through a decellularized Nerve Graft by supplementation with bone marrow stromal cells in fibrin
Cell Transplantation, 2014Co-Authors: Zhe Zhao, Yu Wang, Jiang Peng, Zhiwu Ren, Li Zhang, Quanyi GuoAbstract:Acellular Nerve Grafting is often inferior as well as an inadequate alternative to autoGrafting for the repair of long gaps in peripheral Nerves. Moreover, the injection method is not perfect. During the injection of cells, the syringe can destroy the acellular Nerve structure and the limited accumulation of seed cells. To resolve this problem, we constructed a Nerve Graft by acellular Nerve Grafting. Bone marrow-mesenchymal stromal cells (BM-MSCs) were affixed with fibrin glue and injected inside or around the Graft, which was then used to repair a 15-mm Nerve defect in rats. The acellular Nerve Graft maintained its structure and composition, and its tensile strength was decreased, as determined by two-photon microscopy and a tensile testing device. In vitro, MSCs embedded in fibrin glue survived and secreted growth factors such as Nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). We repaired 15-mm Sprague-Dawley rat sciatic Nerve defects using this Nerve Graft construction, and MSCs injected around the Graft helped improve Nerve regeneration and functional recovery of peripheral Nerve lesions as determined by functional analysis and histology. Therefore, we conclude that supplying MSCs in fibrin glue around acellular Nerves is successful in maintaining the Nerve structure and can support Nerve regeneration similar to the direct injection of MSCs into the acellular Nerve for long Nerve defects but may avoid destroying the Nerve Graft. The technique is simple and is another option for stem cell transplantation.
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repair of Nerve defect with acellular Nerve Graft supplemented by bone marrow stromal cells in mice
Microsurgery, 2011Co-Authors: Zhe Zhao, Yu Wang, Jiang Peng, Zhiwu Ren, Shengfeng Zhan, Yan Liu, Bin Zhao, Qing Zhao, Li Zhang, Quanyi GuoAbstract:The acellular Nerve Graft that can provide internal structure and extracellular matrix components of the Nerve is an alternative for repair of peripheral Nerve defects. However, results of the acellular Nerve Grafting for Nerve repair still remain inconsistent. This study aimed to investigate if supplementing bone marrow mesenchymal stromal cells (MSCs) could improve the results of Nerve repair with the acellular Nerve Graft in a 10-mm sciatic Nerve defect model in mice. Eighteen mice were divided into three groups (n = 6 for each group) for Nerve repairs with the Nerve autoGraft, the acellular Nerve Graft, and the acellular Nerve Graft by supplemented with MSCs (5 × 105) fibrin glue around the Graft. The mouse static sciatic index was evaluated by walking-track testing every 2 weeks. The weight preservation of the triceps surae muscles and histomorphometric assessment of triceps surae muscles and repaired Nerves were examined at week 8. The results showed that the Nerve repair by the Nerve autoGrafting obtained the best functional recovery of limb. The Nerve repair with the acellular Nerve Graft supplemented with MSCs achieved better functional recovery and higher axon number than that with the acellular Nerve Graft alone at week 8 postoperatively. The results indicated that supplementing MSCs might help to improve Nerve regeneration and functional recovery in repair of the Nerve defect with the acellular Nerve Graft. © 2011 Wiley-Liss, Inc. Microsurgery, 2011.
Bernardo Hontanilla - One of the best experts on this subject based on the ideXlab platform.
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facial reanimation with gracilis muscle transfer neurotized to cross facial Nerve Graft versus masseteric Nerve a comparative study using the facial clima evaluating system
Plastic and Reconstructive Surgery, 2013Co-Authors: Bernardo Hontanilla, Diego Marre, Alvaro CabelloAbstract:Background Longstanding unilateral facial paralysis is best addressed with microneurovascular muscle transplantation. Neurotization can be obtained from the cross-facial or the masseter Nerve. The authors present a quantitative comparison of both procedures using the FACIAL CLIMA system. Methods Forty-seven patients with complete unilateral facial paralysis underwent reanimation with a free gracilis transplant neurotized to either a cross-facial Nerve Graft (group I, n=20) or to the ipsilateral masseteric Nerve (group II, n=27). Commissural displacement and commissural contraction velocity were measured using the FACIAL CLIMA system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using the independent samples t test. Mean percentage of recovery of both parameters were compared between the groups using the independent samples t test. Results Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I (p=0.001 and p=0.014, respectively) but not in group II. Intergroup comparisons showed that both commissural displacement and commissural contraction velocity were higher in group II, with significant differences for commissural displacement (p=0.048). Mean percentage of recovery of both parameters was higher in group II, with significant differences for commissural displacement (p=0.042). Conclusions Free gracilis muscle transfer neurotized by the masseteric Nerve is a reliable technique for reanimation of longstanding facial paralysis. Compared with cross-facial Nerve Graft neurotization, this technique provides better symmetry and a higher degree of recovery. Clinical question/level of evidence Therapeutic, III.
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facial reanimation with gracilis muscle transfer neurotized to cross facial Nerve Graft versus masseteric Nerve a comparative study using the facial clima evaluating system
Plastic and Reconstructive Surgery, 2013Co-Authors: Bernardo Hontanilla, Diego Marre, Alvaro CabelloAbstract:BACKGROUND: Longstanding unilateral facial paralysis is best addressed with microneurovascular muscle transplantation. Neurotization can be obtained from the cross-facial or the masseter Nerve. The authors present a quantitative comparison of both procedures using the FACIAL CLIMA system. METHODS: Forty-seven patients with complete unilateral facial paralysis underwent reanimation with a free gracilis transplant neurotized to either a cross-facial Nerve Graft (group I, n=20) or to the ipsilateral masseteric Nerve (group II, n=27). Commissural displacement and commissural contraction velocity were measured using the FACIAL CLIMA system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using the independent samples t test. Mean percentage of recovery of both parameters were compared between the groups using the independent samples t test. RESULTS: Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I (p=0.001 and p=0.014, respectively) but not in group II. Intergroup comparisons showed that both commissural displacement and commissural contraction velocity were higher in group II, with significant differences for commissural displacement (p=0.048). Mean percentage of recovery of both parameters was higher in group II, with significant differences for commissural displacement (p=0.042). CONCLUSIONS: Free gracilis muscle transfer neurotized by the masseteric Nerve is a reliable technique for reanimation of longstanding facial paralysis. Compared with cross-facial Nerve Graft neurotization, this technique provides better symmetry and a higher degree of recovery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.