• Journal of Electrodiagnosis and Neuromuscular Diseases
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• v.20 no.2
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• pp.77-83
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• 2018

Small fiber neuropathy (SFN) mainly affects thinly myelinated $A{\delta}$-fibers and unmyelinated C-fibers presented with neuropathic pain like burning feet or numbness. Many conditions are known as a causes of SFN, metabolic derangement, especially glucose intolerance, is the most frequent cause of SFN. It has been hard to diagnose SFN because there has been lack of specialized test for small nerve fiber. Quantification of intraepidermal nerve fiber density using skin biopsy is promising method to diagnose SFN. A skin biopsy also could give helps to research pathophysiology of SFN by specialized stain method.

• Journal of Korean Neurosurgical Society
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• v.55 no.6
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• pp.370-374
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• 2014

To present a case of cauda equina syndrome (CES) caused by chronic inflammatory demyelinating polyneuropathy (CIDP) which seemed clinically similar to Charcot-Marie-Tooth disease type1 (CMT1). CIDP is an immune-mediated polyneuropathy, either progressive or relapsing-remitting. It is a non-hereditary disorder characterized by symmetrical motor and sensory deficits. Rarely, spinal nerve roots can be involved, leading to CES by hypertrophic cauda equina. A 34-year-old man presented with low back pain, radicular pain, bilateral lower-extremity weakness, urinary incontinence, and constipation. He had had musculoskeletal deformities, such as hammertoes and pes cavus, since age 10. Lumbar spine magnetic resonance imaging showed diffuse thickening of the cauda equina. Electrophysiological testing showed increased distal latency, conduction blocks, temporal dispersion, and severe nerve conduction velocity slowing (3 m/s). We were not able to find genetic mutations at the PMP 22, MPZ, PRX, and EGR2 genes. The pathologic findings of the sural nerve biopsy revealed thinly myelinated nerve fibers with Schwann cells proliferation. We performed a decompressive laminectomy, intravenous IgG (IV-IgG) and oral steroid. At 1 week after surgery, most of his symptoms showed marked improvements except foot deformities. There was no relapse or aggravation of disease for 3 years. We diagnosed the case as an early-onset CIDP with cauda equine syndrome, whose initial clinical findings were similar to those of CMT1, and successfully managed with decompressive laminectomy, IV-IgG and oral steroid.

• Annals of Clinical Neurophysiology
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• v.15 no.1
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• pp.19-23
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• 2013

Some patients with leprosy may present with atypical features, such as isolated peripheral neuropathy without skin lesions, or marked proprioceptive dysfunction. We report a 56-year-old female who presented with predominant proprioceptive loss without skin lesion, but was finally confirmed as leprous neuropathy by sural nerve biopsy. It is postulated that large myelinated fibers were affected by chronic immunological reactions triggered by inactive bacterial particles, producing a peripheral neuropathy presenting as predominant proprioceptive sensory loss without typical skin lesions.

• Applied Microscopy
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• v.17 no.2
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• pp.41-54
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• 1987

This experiment was performed to investigate the acute and chronic effects of lead on cerebral cortex. In acute treatment, mouse were injected with lead acetate at dose of 0.3 mmole/kg body weight, and in chronic treatment, mouse were supplied 0.03 M lead acetate sol. in the place of water. After treatment, mouse were sacrificed at time intervals of 24, 48, 72, and 96 hours in acute treatment and at time intervals of 4 weeks and 8 weeks in chronic treatment. In acute treatment, acetylcholinesterase activity is reduced at 72 hours and recovered at 96 hours in homogenate, and reduced at 24 hours and recovered at 72 hours in crude synaptosomes. In chronic treatment, acetylcholinesterase activity is increased in young mouse but reduced in mother mouse. Ultrastructural changes were composed of swelling of Golgi apparatus, nerve terminals with diminished synaptic vesicles, and vacuolated myeline lamellae of myelinated axon.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.205-212
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• 2006

Using adipose derived stem cells(ASCs), neurogenic differentiation was induced in a mono layered culture medium containing neuronal induction agents. Cells differentiated to the neuronal cells were observed with a inverted microscope and immunofluorecent study. We made a 15 mm long defect in the sciatic nerve of 14 rats and connected a silicone tube to the defect. Then, we mixed neuronal progenitor cells differentiated from ASCs with collagen gel and grafted them to a group of rats(experimental group) and grafted only collagen gel into another group(control group). In 4 and 8 weeks after the graft, histological observation was made. According to the result, the number and diameter of myelinated axons were significantly increased in the experimental group. In addition, the nerve conduction velocity was improved more in the experimental group and neovascularity also increased. Moreover, reaction with S100 and p75 was observed in regenerated nerves in the experimental group, suggesting that the grafted cells were differentiated into supportive cells such as Schwann's cells. In conclusion, this research proved that ASCs can multiply and differentiate into neuronal cells. If they are grafted into nerve defects, the grafted cells are differ entiated into supportive cells such as Schwann's cells and thus contribute to nerve regeneration. Accordingly, the use of adipose tissue obtained easily without the limitation of donor site can be greatly helpful in treating peripheral nerve defects.

• The Korean Journal of Pain
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• v.14 no.1
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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.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.326-335
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• 1996

Background: Though a number of studies have described the distribution of substance P(SP)-like immunoreactivity in the spinal cord, they have been focused on lamina I and II of the dorsal horn and there are little morphological studies on the topographic distribution and ultrastructure of the SP immunoreactive neurons especially in the ventral horn of the spinal cord. this study was conducted to identify distribution pattern of SP immunoreactive neurons and to difine the synaptic organization of their processes in ventral horn of the thoracic cord of the cat by preembbeding immunocytochemical method using SP antiserum. Methods: Five adults cats of either sex were used and deeply anesthetized by intramuscular injection of ketamine. After removal of the spinal cord, samples of thoracic cord were taken and placed in fresh fixative at $4^{\circ}C$ for 2 hours. Transverse sections $50{\mu}m$ thick were processed using the preembbeding immunocytochemical method and incubated consecutively in the specific primary antibody and the 10% normal goat serum, the rabbit anti-substance P antiserum, the biotin-labelled goat anti-rabbit IgG and finally the avidin-biotin-peroxidase complex. The processed tissue sections were throughly washed and stained in the black with 1% uranyl acetate. Section were examined on a electron microscope. Results: 1) SP immunoreactive neurons were observed in the gray matter around central canal. 2) In lamina I and II SP immunoreactivity was observed in both myelinated and unmyelinated nerve fibers, but in ventral horn only in the unmyelinated nerve fibers. 3) SP immunoreactive axon terminals with small round and large dense core vesicles made chemical synapses onto the dendrites of motor neurons in the ventral horn. Conclusion: SP immunoreactive neurons might play an important role in modulation of motor neurons in the ventral horn of the thoracic cord of the cat.

• The Korean Journal of Pain
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• v.35 no.2
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• pp.160-172
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• 2022

Background: The authors established an in vitro model of diabetic neuropathy based on the culture system of primary neurons and Schwann cells (SCs) to mimic similar symptoms observed in in vivo models of this complication, such as impaired neurite extension and impaired myelination. The model was then utilized to investigate the effects of insulin on enhancing neurite extension and myelination of diabetic neurons. Methods: SCs and primary neurons were cultured under conditions mimicking hyperglycemia prepared by adding glucose to the basal culture medium. In a single culture, the proliferation and maturation of SCs and the neurite extension of neurons were evaluated. In a co-culture, the percentage of myelination of diabetic neurons was investigated. Insulin at different concentrations was supplemented to culture media to examine its effects on neurite extension and myelination. Results: The cells showed similar symptoms observed in in vivo models of this complication. In a single culture, hyperglycemia attenuated the proliferation and maturation of SCs, induced apoptosis, and impaired neurite extension of both sensory and motor neurons. In a co-culture of SCs and neurons, the percentage of myelinated neurites in the hyperglycemia-treated group was significantly lower than that in the control group. This impaired neurite extension and myelination was reversed by the introduction of insulin to the hyperglycemic culture media. Conclusions: Insulin may be a potential candidate for improving diabetic neuropathy. Insulin can function as a neurotrophic factor to support both neurons and SCs. Further research is needed to discover the potential of insulin in improving diabetic neuropathy.

• Journal of Ginseng Research
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• v.27 no.3
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• pp.103-109
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• 2003

We investigated the effect of ginseng total saponin (GTS) on the regeneration process of experimentally crush injured rat sciatic nerves. The bilateral sciatic nerves of fifty adult male Sprague-Dawley rats were compressed surgically with a straight hemostat for 30 seconds with 1 mm width. Twenty rats were divided into four groups to test the dose-dependent effect of GTS (0, 50, 100, or 150 mg/kg, i.p.). Saline for vehicle control group or GTS dissolved in saline was administerd for three weeks. After that period of time, the numbers of total myelinated axon and degenerated myelin in the sciatic nerves of bilateral legs were examined and analyzed using image analysis system to confirm a morphological effect of GTS. We found that the most effective concentration of GTS for the regeneration of damaged sciatic nerve was 150 mg/kg. In another set of experiment, thirty rats were divided into two groups as saline-treated vehicle group and GTS-treated group (150 mg/kg, i.p.) for three weeks. Every week we examined the numbers of total myelinated axon and degenerated myelin in the sciatic nerves of bilateral legs using image analysis system to evaluate the effect of GTS on injured nerves. We found that the regeneration of damaged sciatic nerves was facilitated in GTS-treated group compared to saline-treated group until two weeks. However, after that period of time we could not observe the significant difference between saline-treated group and GTS-treated group. These results suggest that GTS is a useful adjuvant therapy for the regeneration of the peripheral nerve injury in short period of treatment.

• The Korean Journal of Pain
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• v.5 no.2
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• pp.213-220
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• 1992

The sciatic nerves of anesthetized rabbits were exposed and stimulated by a nerve stimulator in order to observe the myoneural response. These rabbits were divided into three groups and respectively injected with morphine (Group 1), meperidine(Group 2) and pentazocine (Group 3). The sciatic nerves were stimulated periodically and gait changes were observed to see the myoneural activity after the injections. When the distal part of the sciatic nerves were stimulated by the nerve stimulator after the respective drug injections, the normal muscle twitch responses were observed in all the progressional stages of Group 1. However, in Group 2 and 3, the muscle twitch responses decreased gradually, finally disappearing after approximately 10 minutes in these two groups. Complete motor paralysis continued for about 60 minutes. The muscle reactions returned to normal approximately 90 minutes after injection. Specimens drug-injected tissues were severed 4 hours, 24 hours and 1 week after injection respectively. These tissue were investigated under light as well as electron microscopy. The tissue revealed rare to moderate vacuolizations scattered in the axons of the myelinated and unmyelinated nerves of some of the specimens; however, there were no significant pathologic lesions. These results provide evidence that neurophysiologically, meperidine and pentazocine have a local anesthetic-like effect such as motor paralysis, but morphine does not. In addition, the results indicated that neurohistologically, the three narcotics have no significant toxic effects on the nerve tissue.