• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권6호
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• pp.465-473
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• 2004

Purpose : The essential triad for nerve regeneration is nerve conduit, supporting cell and neurotrophic factor. In order to improve the peripheral nerve regeneration, we used polyglycolic acid(PGA) tube and brain-derived neurotrophic factor(BDNF) gene transfected Schwann cells in sciatic nerve defects of SD rat. Materials and methods : Nerve conduits were made with PGA sheet and outer surface was coated with poly(lactic-co-glycolic acid) for mechanical strength and control the resorption rate. The diameter of conduit was 1.8mm and the length was 17mm Schwann cells were harvested from dorsal root ganglion(DRG) of SD rat aged 1 day. Schwann cells were cultured on the PGA sheet to test the biocompatibility adhesion of Schwann cell. Human BDNF gene was obtained from cDNA library and amplified using PCR. BDNF gene was inserted into E1 deleted region of adenovirus shuttle vector, pAACCMVpARS. BDNF-adenovirus was multiplied in 293 cells and purified. The BDNF-Adenovirus was then infected to the cultured Schwann cells. Left sciatic nerve of SD rat (250g weighing) was exposed and 14mm defects were made. After bridging the defect with PGA conduit, culture medium(MEM), Schwann cells or BDNF-Adenovirus infected Schwann cells were injected into the lumen of conduit, respectively. 12 weeks after operation, gait analysis for sciatic function index, electrophysiology and histomorphometry was performed. Results : Cultured Schwann cells were well adhered to PGA sheet. Sciatic index of BDNF transfected group was $-53.66{\pm}13.43$ which was the best among three groups. The threshold of compound action potential was between 800 to $1000{\mu}A$ in experimental groups which is about 10 times higher than normal sciatic nerve. Conduction velocity and peak voltage of action potential of BDNF group was the highest among experimental groups. The myelin thickness and axonal density of BDNF group was significantly greater than the other groups. Conclusion : BDNF gene transfected Schwann cells could regenerate the sciatic nerve gap(14mm) of rat successfully.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권1호
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• pp.96-107
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• 1995

The purpose of this experimental study was to examine and compare the regeneration capacity between crushed nerve & transected nerve. For this study, 20 Sprague-Dawley female albino rats were used as experimental animals and divided into two groups. In group 1, the sciatic nerves were crushed 6mm. in length for 1 min. using maximum force with a needle holder. In group 2, the sciatic nerves were resected 6mm. in length and the gaps were encased by inserting the proximal and distal stumps into each end of silicone tubes. The animals were sacrificed 1 month & 2 months after the experiment. All specimens were fixed in 2.5% glutaraldehyde and 1% Osmium tetroxide solution then embedded in epon 812 and were cross-sectioned at $1{\mu}m.$ After these procedures, specimens were observed under Light microscope. The results obtained were as follows. 1. Group 1 showed greter diameters of regenerating nerves than group 2. 2. Group 1 showed greater number of axons than group 2.

• 통합자연과학논문집
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• 제15권3호
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• pp.123-129
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• 2022

Schwann cells play a critical role for myelination in peripheral nerve system. It also plays an important role in nerve protection and regeneration. In peripheral nerve damage, regeneration is induced by the migration and proliferation of Schwann cells which were promoted by suppressing the oxidative stress. In this study, Human placental extract was prepared by homogenization and estimated its efficacy in RSC96 cells. Placental extract exhibited a protective effect against hydrogen peroxide-induced oxidative stress in RSC96 cells, confirmed by MTT assay. Furthermore, placental extract decreased intracellular ROS against oxidative stress, confirmed by DCFH-DA assay. Autophagy was visualized with Cyto-ID staining to confirm the autophagy activity of placental extracts. The activity of autophagy was confirmed by immunoblot analysis of autophagy flux-associated proteins such as LC3 conversion and SQSTM1 degradation. Thus, we confirmed the antioxidant effect of placental extract to protect RSC96 cells from oxidative stress, and observed that it activated autophagy and restored autophagy flux.

• Archives of Reconstructive Microsurgery
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• 제8권1호
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• pp.92-96
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• 1999

Neuroma is formed by abnormal, incomplete nerve regeneration after nerve injury. A painful neuroma in the hand can be psychologically and physically disabling. The goal of treating painful neuroma is to relieve pain and to restore nerve function. A numerous treatment modality was reported for alleviating the problem. These treatments include crushing the neuroma, ligating it, burying in soft tissue, bone, and muscle, injecting it with alcohol, phenol, and steroid, capping it with silicone cuff. But, none of these methods has been uniformly successful, although each has its advocates. No one technique reliably prevents formation of a painful neuroma. However, the principles of treatment is resection of neuroma and proximal stump of the nerve is transposed to appropriate adjacent tissue. Our current technique was resection of neuroma with partial normal neural tissue, and then the nerve ending was transposed and sutured to the side of the proximal stump with 10-0 nylon, so end-to-side neurorrhaphy was made. The nerve ending had to be placed and fixed into the proximal nerve epineurium like as a figure of a loop. We believe this technique is another useful method for the treatment of painful neuroma.

• The Journal of Korean Physical Therapy
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• 제13권3호
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• pp.569-578
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• 2001

The purpose of the present study was to examine the functional recovery of the crushed sciatic nerve of rats after low-power laser irradiation applied to the corresponding segments of the spinal cord. After a crushed injury on the left sciatic nerve in rats. low-power laser irradiation was applied transcutaneously to corresponding segments of the spinal cord immediately after suture the wound by using 2000 mW, 2000Hz, 830 nm CaAIAs(Gallium-aluminum-arsenide) semiconductor diode laser. The laser treatment was performed with 10 minutes daily for 4 successive weeks. Functional recovery was evaluated per weekly following injury by sciatic function index(SFI),using data obtained by walking track analysis. For four weeks after crush injury, experimental group had significantly greater functional improvement than control group(${\alpha}$=0.05). In a experimental group, SFI was significantly increased for three weeks, but control group not increased for two weeks. This study suggests that low-power laser irradiation applied directly to the spinal cord can improve functional recovery of the crushed sciatic nerve in rats.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권2호
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• pp.148-154
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• 2012

Peripheral nerve injuries in the oral and maxillofacial regions require nerve repairs for the recovery of sensory and/or motor functions. Primary indications for the peripheral nerve grafts are injuries or continuity defects due to trauma, pathologic conditions, ablation surgery, or other diseases, that cannot regain normal functions without surgical interventions, including microneurosurgery. For the autogenous nerve graft, sural nerve and greater auricular nerve are the most common donor nerves in the oral and maxillofacial regions. The sural nerve has been widely used for this purpose, due to the ease of harvest, available nerve graft up to 30 to 40 cm in length, high fascicular density, a width of 1.5 to 3.0 mm, which is similar to that of the trigeminal nerve, and minimal branching and donor sity morbidity. Many different surgical techniques have been designed for the sural nerve harvesting, such as a single longitudinal incision, multiple stair-step incisions, use of nerve extractor or tendon stripper, and endoscopic approach. For a better understanding of the sural nerve graft and in avoiding of uneventful complications during these procedures as an oral and maxillofacial surgeon, the related surgical anatomies with their harvesting tips are summarized in this review article.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1998년도 한국생물과학협회 학술발표대회
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• pp.233.2-233
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• 1998

No Abstract, See Full Text

• 대한치과의사협회지
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• 제23권9호통권196호
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• pp.783-801
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• 1985

• 한국진공학회:학술대회논문집
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• 한국진공학회 2006년도 제31회 학술논문발표회 초록집
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• pp.49-49
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• 2006

• The Korean Journal of Pain
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• 제14권1호
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• pp.83-92
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• 2001

Background: This study was undertaken to observe the functional changes of the hind limb and histopathological changes in the sciatic nerve after an injection of alcohol or phenol, which are commonly used neurolytic agents, highlighting the time of recovery. Methods: Forty-eight Sprague-Dawley rats weighing 200-300 g were used for the experiment. Histopathological changes under the electron microscope, were observed in the distal part of the sciatic nerve, into which 0.1 ml of alcohol or phenol was injected. This was severed in 3 rats of each group at 10 minutes, 1 hour, 24 hours, 3 days, 1, 2, 4 and 6 weeks later. The functional changes in the hind limbs were observed for 6 weeks by noting their walking pattern. Results: Following the injection of alcohol or phenol into the right sciatic nerve, the right hind limb showed a severe pronounced motor weakness and obvious gait changes. About 2 weeks later, gradual improvement of gait changes began, and after 6 weeks, the motor weakness and gait changes were no longer perceptible in both groups. The findings of any histopathological change were similar in both alcohol or phenol groups. At 10 minutes after injection, destructive lesions were confined to the unmyelinated fibers and the myelin sheath of small the myelinated fibers. On the 3rd day and at 1 week, pathologic changes in axonal fibers and Schwann cells were in being phagocytized in spite of myelin restitution. From 2 to 4 weeks, axonal regeneration and remyelination appeared at the same time a myelin disintegration and axonolysis. At 6 weeks, neural regeneration was similar to that of the contralateral control group. Conclusions: These results suggest that functional and histopathological changes, after injection of neurolytics into the peripheral nerves, are quite similar in both alcohol and phenol groups. The progression of functional and histopathological changes become more obvious according to the time interval following the injection. Consequently, side effects that develop following the use of alcohol or phenol may begin to improve around the time that nerve regeneration occurs, i.e., two to four weeks later.