The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
A. Groger - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of functional Nerve recovery with Visual-SSI--a novel computerized approach for the assessment of the static sciatic index (SSI).
Journal of neuroscience methods, 2008Co-Authors: Ahmet Bozkurt, S. Tholl, Sarah Wehner, Julian Tank, Miriam M. Cortese, Dan Mon O'dey, Ronald Deumens, F. Lassner, Frank Schügner, A. GrogerAbstract:Complete Nerve transection (neurotmesis) of the rat sciatic Nerve is a well-established animal model. The most frequently used behavioural for evaluation of neurotmesis-induced deficits is the walking track analysis with calculation of the sciatic functional index (SFI). More recently, the static sciatic index (SSI) has been developed, which shows a good correlation with the SFI. However, despite all advantages (high accessibility, easy handling, high accuracy, cost-effectiveness), the SSI is still not widely used. We, therefore, developed a novel programme ("Visual-SSI"), which will be made freely available for the assessment of the SSI. As gold-standard for the treatment of neurotmesis-induced Nerve gaps, autologous Nerve Transplantation studies in the rat sciatic Nerve model (n=16 [6 weeks], n=8 [12 weeks]) were carried out to test the effectiveness and feasibility of the Visual-SSI software. We observed a significant recovery starting from the pre-operative condition over the 3rd, 6th, 9th weeks until the 12th week after surgery (p 0.05). The present method combines efficiency (simplicity of use, rapid and economical setup) with accurate and precise quantification of the functional regeneration in the sciatic Nerve lesion model of the rat.
Ahmet Bozkurt - One of the best experts on this subject based on the ideXlab platform.
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retrograde tracing and toe spreading after experimental autologous Nerve Transplantation and crush injury of the sciatic Nerve a descriptive methodological study
Journal of Brachial Plexus and Peripheral Nerve Injury, 2014Co-Authors: Sabien Van Neerven, Ahmet Bozkurt, Dan Mon Odey, J Scheffel, A Boecker, Janphilipp Stromps, Sebastian E Dunda, Gary A Brook, Norbert PalluaAbstract:Evaluation of functional and structural recovery after peripheral Nerve injury is crucial to determine the therapeutic effect of a Nerve repair strategy. In the present study, we examined the relationship between the structural evaluation of regeneration by means of retrograde tracing and the functional analysis of toe spreading. Two standardized rat sciatic Nerve injury models were used to address this relationship. As such, animals received either a 2 cm sciatic Nerve defect (neurotmesis) followed by autologous Nerve Transplantation (ANT animals) or a crush injury with spontaneous recovery (axonotmesis; CI animals). Functional recovery of toe spreading was observed over an observation period of 84 days. In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading. After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons) and spinal cord (motor neurons), respectively. No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals. In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading) measured by SSI and the number of labelled (motor and sensory) neurons evaluated by retrograde tracing. The present findings demonstrate that a multimodal approach with a variety of independent evaluation tools is essential to understand and estimate the therapeutic benefit of a Nerve repair strategy.
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Evaluation of functional Nerve recovery with Visual-SSI--a novel computerized approach for the assessment of the static sciatic index (SSI).
Journal of neuroscience methods, 2008Co-Authors: Ahmet Bozkurt, S. Tholl, Sarah Wehner, Julian Tank, Miriam M. Cortese, Dan Mon O'dey, Ronald Deumens, F. Lassner, Frank Schügner, A. GrogerAbstract:Complete Nerve transection (neurotmesis) of the rat sciatic Nerve is a well-established animal model. The most frequently used behavioural for evaluation of neurotmesis-induced deficits is the walking track analysis with calculation of the sciatic functional index (SFI). More recently, the static sciatic index (SSI) has been developed, which shows a good correlation with the SFI. However, despite all advantages (high accessibility, easy handling, high accuracy, cost-effectiveness), the SSI is still not widely used. We, therefore, developed a novel programme ("Visual-SSI"), which will be made freely available for the assessment of the SSI. As gold-standard for the treatment of neurotmesis-induced Nerve gaps, autologous Nerve Transplantation studies in the rat sciatic Nerve model (n=16 [6 weeks], n=8 [12 weeks]) were carried out to test the effectiveness and feasibility of the Visual-SSI software. We observed a significant recovery starting from the pre-operative condition over the 3rd, 6th, 9th weeks until the 12th week after surgery (p 0.05). The present method combines efficiency (simplicity of use, rapid and economical setup) with accurate and precise quantification of the functional regeneration in the sciatic Nerve lesion model of the rat.
Satheesha B Nayak - One of the best experts on this subject based on the ideXlab platform.
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Sural Nerve entrapment in gastrocnemius muscle – a case report
2007Co-Authors: Bincy M George, Satheesha B NayakAbstract:Although the sural Nerve is the most extensively studied Nerve in man, there is a dearth of data regarding the normal variations in the size and distribution of axons in normal subjects. The sural Nerve is the most frequently used sensory Nerve in Nerve Transplantation. The knowledge of variations in its course and distribution play an important role in the surgical procedures. Here, we report an entrapment of the sural Nerve in the gastrocnemius. Neuroanatomy; 2007; 6: 41–42.
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Sural Nerve and short saphenous vein entrapment—a case report
Indian Journal of Plastic Surgery, 2005Co-Authors: Satheesha B NayakAbstract:Although the sural Nerve is the most extensively studied Nerve in man, there is a dearth of data regarding the normal variations in the size and distribution of axons in normal subjects. Since the sural Nerve is the most frequently used sensory Nerve in Nerve Transplantation, knowledge of variations in its course and distribution plays an important role in the surgical procedures. Here, an entrapment of the sural Nerve in the gastrocnemius is reported. The short saphenous vein also passed through the gastrocnemius muscle along with the sural Nerve.
Shinya Kawai - One of the best experts on this subject based on the ideXlab platform.
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Vascularized allogeneic joint, muscle, and peripheral Nerve Transplantation.
Clinical orthopaedics and related research, 1995Co-Authors: Keiichi Muramatsu, Kazuteru Doi, Shinya KawaiAbstract:Joint, muscle, and peripheral Nerve alloTransplantation was done with short-term cyclosporine immunosuppression. To investigate the effectiveness of this regimen, the allografts were examined after withdrawal of cyclosporine. Using inbred rats, vascularized orthotopic alloTransplantation of the knee joint, rectus femoris muscle, and great saphenous Nerve was done across a major histocompatibility complex barrier. Cyclosporine was administered for 4 to 6 weeks postoperatively, and the grafts were observed until Week 12. Long-term administration of cyclosporine and nonvascularized Transplantation were used as controls. Although rejection of the allografts could be delayed for 2 to 3 weeks after the withdrawal of cyclosporine, all transplanted joints, muscles, and Nerves eventually were rejected completely and immunotolerance could not be induced. The joint allografts at first achieved bony union, but eventually were destroyed because of pathologic fractures. In the group treated with long-term immunosuppression, the allografts showed no rejection and functional improvement was obtained. However, rats given a high dose (10 mg/kg per day) of cyclosporine died from adverse effects of the drug by Week 12. In the nonvascularized treatment group, the results were poor in every patient, and the need for graft vascularization for skeletal tissue alloTransplantation was confirmed.
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Vascularized allogeneic Nerve Transplantation with cyclosporine immunosuppression
Annals of plastic surgery, 1994Co-Authors: Keiichi Muramatsu, Kazuteru Doi, Shinya KawaiAbstract:Allogenic grafts have many advantages over autogenous grafts. An experimental rat model using the great saphenous Nerve was developed to study the reconstruction of long peripheral Nerve defects with vascularized allogeneic Nerve grafts, and the effects of cyclosporine therapy on graft survival were assessed. In animals receiving short-term immunosuppression, the number of regenerated axons increased steadily during the treatment, but rejection began immediately after cyclosporine was discontinued. As the tissues transplanted with the Nerves underwent necrosis, the grafts showed demyelination. In contrast, in animals receiving long-term cyclosporine therapy, Nerve regeneration assessed in terms of the myelinated axon count was excellent until at least 12 weeks postoperatively but was less active than in vascularized autografts or conventional allografts. These results indicate that the short-term immunosuppressive therapy with cyclosporine cannot produce immunological tolerance of vascularized Nerve allografts. In addition, even when administration of cyclosporine was prolonged, Nerve regeneration did not exceed that in autografts.
Zhenbing Chen - One of the best experts on this subject based on the ideXlab platform.
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Dihydrotestosterone Treatment Accelerates Autograft Reversal Sciatic Nerve Regeneration in Rats
Neurochemical research, 2018Co-Authors: Xiaofan Yang, Pingping Xue, Ruozheng Wei, Xin Liu, Zhenyu Liu, Yanhua Chen, Zhenbing ChenAbstract:Neuroactive steroids such as progesterone, testosterone, and their derivatives have been widely studied for their neuroprotective roles in the nervous system. Autologous Nerve Transplantation is considered as the gold standard repair technique when primary suture is impossible; nevertheless, this method is far from ideal. In this study, we aimed to explore the impact of dihydrotestosterone (DHT), a 5α-reduced derivative of testosterone, on the recovery of peripheral Nerve injury treated with autologous Nerve Transplantation. Sprague–Dawley rats were subjected to a 10-mm right side sciatic Nerve reversed autologous Nerve Transplantation and randomly divided into groups that received DHT or DHT + flutamide (an androgen receptor blocker) daily for 8 weeks after operation. Our results demonstrated that DHT could speed up the rate of axonal regeneration and increase the expression of myelin protein zero (P0) in autograft reversal sciatic Nerves. Thus, our study provided new insights into improving the prognosis of patients with long gap peripheral Nerve defects.
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Effect of transforming growth factor beta1 plasmid on frosted allogenic Nerve Transplantation
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery, 2004Co-Authors: Yu-xiong Weng, Zhenbing Chen, Qi-shun HuangAbstract:OBJECTIVE To study the effect of transforming growth factor beta1 (TGF-beta1) plasmid on poly frosted-defrosted allogenic Nerve Transplantation. METHODS Forty Wistar rats were randomly divided into two groups equally. A 2.0 cm sciatic Nerve segment, 5 mm away from infrapiriformis muscle space, was removed and the defect was repaired with poly frosted-defrosted allogenic Nerve. The TGF-beta1 plasmids were injected into the Nerve anastomosis and adjacent muscles in the experimental group, normal saline in the control group. The Nerve specimens were sectioned for staining in the 6th and 12th weeks. Axonal count and statistical analyses were done. RESULTS The grafted and distal Nerve segments showed regenerated fibers in both groups. In the experimental group, less edema and more Nerve fibers were observed in the 6th week. The grafted Nerve segment was filled with regeneration axons, the myelinated Nerve fibers arranged regularly, and the axons and the myelin sheaths developed well in the 12th week. There was significant difference in the number of regenerating axons between the experimental group 98.6 +/- 4.8/microm2 and control group 75.8 +/- 5.1/microm2 (P < 0.01). CONCLUSION Multiple frost-defrost of allogenic Nerve can reduce its antigenicity and increase its usefulness in repairing Nerve defects. Local use of TGF-beta1 plasmid can enhance immunosuppression to reduce immuno rejection.