• Annals of Clinical Neurophysiology
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• 제14권2호
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• pp.64-71
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• 2012

Background: It is generally accepted that upper motor neuron (UMN) lesion can alter lower motor neuron (LMN) function by the plasticity of neural circuit. However there have been only few researches regarding the axonal excitability of LMN after UMN injury especially during the acute stage. The aim of this study was to investigate the nerve excitability properties of the LMNs following an acute to subacute supratentorial corticospinal tract lesion. Methods: An automated nerve excitability test (NET) using the threshold tracking technique was utilized to measure multiple excitability indices in median motor axons of 15 stroke patients and 20 controls. Testing of both paretic and non-paretic side was repeated twice, during the acute stage and subacute stage. The protocols calculated the strength-duration time constant from the duration-charge curve, parameters of threshold electrotonus (TE), the current-threshold relationship from sequential sub-threshold current, and the recovery cycle from sequential supra-threshold stimulation. Results: On the paretic side, compared with the control group, significant decline of superexcitablity and increase in the relative refractory period were observed during the subacute stage of stroke. Additionally, despite the absence of statistical significance, a mildly collapsing in ('fanning in') of the TE was found. Conclusions: Our results suggest that supratentorial brain lesions can affect peripheral axonal excitability even during the early stage. The NET pattern probably suggests background membrane depolarization of LMNs. These features could be associated with trans-synaptic regulation of UMNs to LMNs as one of the "neural plasticity" mechanisms in acute brain injury.

• 대한임상전기생리학회지
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• 제9권2호
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• pp.19-24
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• 2011

Purpose : This study is to examine the effects of transcranial direct current stimulation on the excitability of the central neuron. Methods : This study selected 24 suitable women in their twenties. A positive electrode of transcranial direct current stimulation was placed on the primary motor area (M1) C4 and a negative electrode was placed on the left supraobital. A stimulation of 0.04mA/$cm^2$ was applied for 20 minutes. H-reflex and V wave used diagnostic electromyography. An active electrode was placed at the muscle belly of the medial gastrocnemius muscle at a prone posture. An electrical stimulation was given to the posterior tibial nerve. Measurements were made before and after the stimulation. All data were analyzed with SPSS 12.0 and between each measuring before and after the change of the H-reflex and V wave amplitude. Results : There were no significant differences in all H wave, M wave, and V wave amplitude before and after transcranial direct current stimulation. There were no significant differences in the change of H/M ratio and V/M ratio before and after transcranial direct current stimulation. Conclusion : We know that transcranial direct current stimulation cannot have an influence on a normal grown-up person's central neuron.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2003년도 제27회 추계학술대회
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• pp.73-73
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• 2003

Purpose: To determine the motor cortex dysfunction in hemiparetic patients due to deep intracerebral hematoma, authors performed proton magnetic resonance spectroscopy (lH MRS) for the evaluation of biochemical changes in the cortex on affected hemisphere according to axonal injury at the level of internal capsule. Methods: Ten control subjects and 14 patients with documentable hemiparesis of varying severity hemiparesis were included. All the hemiparesis was caused by deep intracerebral hematoma (putaminal and thalamic hemorrhage). In vivo 1H MRS study was performed on a 3T MRI/MRS system using STEAM sequence. As a single-voxel technique, Spectral parameters were: 20 ms TE, 2000 ms TR, 128 averages, 2500 Hz spectral width, and 2048 data points. Results: We found that the mean N-acetylaspartate (NAA)/phosphocreatine (Cr) and NAA/choline (Cho) ratios were significantly decreased in the motor cortex of the hemiparesis patients compared with control subjects. Conclusions: 1H MRS examinations of the motor cortex might help to differentiate distinct clinical entities of hemiparesis and to monitor pharmacological effects in therapeutic trials, providing a quantitative biological marker for motor neuron dysfunction. Acknowledgement: This study was supported by a grant of the Center for Functional and Metabolic Imaging Technology, Ministry of Health & Welfare, Republic of Korea. (02-PJ3-PG6-EV07-000).

• 한국전문물리치료학회지
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• 제2권2호
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• pp.73-84
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• 1995

Spasticity has been defined as a motor disorder characterised by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks resulting in hyperexcitability of the stretch reflexes as one component of the upper motor neuron syndrome. Weakness and loss of dexterity, however, are considered to be more disabling to the patient than changes in muscle tone. The discussion includes the important role that alterations in the physiology of motor units, notably changes in firing rates and muscle fiber atrophy, play in the manifestation of muscle weakness. This paper considers both the neural and mechanical components of spasticity and discusses, in terms of clinical intervention, the implications arising from recent research. Investigations suggest that the resistance to passive movement in individuals with spasticity is due not only to neural mechanisms but also to changes in mechanical properties of muscle. The emphasis is on training the individual to gain control over the muscles required for different tasks, and on preventing secondary and adaptive soft tissue changes and ineffective adaptive motor behaviours.

• 동의생리병리학회지
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• 제17권3호
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• pp.738-741
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• 2003

In order to evaluate the cytotoxicity of methylmercuric chloride(MMC) in cultured spinal motor neurons of neonatal mouse, cell viability was measured by MTT assay in spinal motor neurons treated with 1-30 μM MMC for 48 hours. And also, the protective effect of Radix Polygoni Multiflori(RPM) was examined by cell viability in these cultures. Cell viability was significantly decreased in dose-dependent manner after cultured cells were exposured to 20 μM MMC for 48 hours. Protective effect of RPM on MMC-mediated toxicity was very effective in these cultures. From above the results, it suggests that MMC has toxic effect in cultured mouse spinal motor neurons and herb extract such as RPM is very effective in blocking the neurotoxicity induced by MMC.

• 한방재활의학과학회지
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• 제21권4호
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• pp.13-22
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• 2011

Objectives : This Study was performed to evaluate the effects of Scutellariae Radix(SR) water-extract on the tissue and neuronal apoptosis of the spinal cord injury(SCI). Methods: SCI was induced by mechanical contusion following laminectomy of 10th thoracic vertebra in Sprague-Dawley rats. SR was orally given once a day for 7 days after SCI. Neuronal apoptosis was examined with terminal deoxynucleotidyl transferase-mediated dUTPnick-end labeling(TUNEL) assay. Bax (Bcl-2-asociated X protein), Bcl-2(B-cell blastoma 2), c-Fos(FBJ osteosarcoma oncogene) expressions were examined using immuno-histochemistry. Individual TUNEL and immuno-labeled cells expressing Bax, Bcl-2 and c-Fos were counted on the same level in peri-damaged region and in ventral horn. Results: 1. SR significantly reduced number of TUNEL labeled apoptotic cells induced by the spinal cord contusion injury. 2. SR significantly reduced Bax positive cells expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. 3. SR strengthened Bcl-2 expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. 4. SR reduced c-Fos expression on the motor neuron in the ventral horn induced by the spinal cord contusion injury. Conclusions : These results suggest that SR plays an inhibitory role against neuronal apoptosis and has significant effects for locomotor disfunction induced by SCI.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1509-1510
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• 2013

• 동의생리병리학회지
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• 제17권2호
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• pp.457-460
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• 2003

It has been suggested that oxidative stress of reactive oxygen species(ROS) may play an important role in the pathogenesis of neurological disorder. The aim of this study was to elucidate the oxidative stress of glucose oxidase(GO) in the cultured mouse spinal motor neurons and the preventing effect of Benincasae Semen(BS) on ROS-induced neurotoxicity. Cytotoxic effect of GO and protective effect of BS were performed by MTT assay. 30mU/ml GO decreased cell viability in dose-and time-dependent mannner, and BS diminished GO-induced neurotoxicity in these cultures. From above the results, ROS such as GO has toxic effect, and herb extract of BS is very effective against GO-induced neurotoxicity in cultured spinal motor neurons of neonatal mouse.

• Journal of Yeungnam Medical Science
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• 제39권3호
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• pp.181-189
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• 2022

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative condition characterized by loss of motor neurons, resulting in motor weakness of the limbs and/or bulbar muscles. Pain is a prevalent but neglected symptom of ALS, and it has a significant negative impact on the quality of life of patients and their caregivers. This review outlines the epidemiology, clinical characteristics, underlying mechanisms, and management strategies of pain in ALS to improve clinical practice and patient outcomes related to pain. Pain is a prevalent symptom among patients with ALS, with a variable reported prevalence. It may occur at any stage of the disease and can involve any part of the body without a specific pattern. Primary pain includes neuropathic pain and pain from spasticity or cramps, while secondary pain is mainly nociceptive, occurring with the progression of muscle weakness and atrophy, prolonged immobility causing degenerative changes in joints and connective tissue, and long-term home mechanical ventilation. Prior to treatment, the exact patterns and causes of pain must first be identified, and the treatment should be tailored to each patient. Treatment options can be classified into pharmacological treatments, including nonsteroidal anti-inflammatory drugs, antiepileptic drugs, drugs for cramps or spasticity, and opioid; and nonpharmacological treatments, including positioning, splints, joint injections, and physical therapy. The development of standardized and specific assessment tools for pain-specific to ALS is required, as are further studies on treatments to reduce pain, diminish suffering, and improve the quality of life of patients with ALS.

• 한국지능시스템학회논문지
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• 제24권6호
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• pp.609-614
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• 2014

소뇌 운동실조는 점차 진행되는 신경퇴행질병이며 운동 조절을 위한 기능의 상실을 동반하기에 환자의 삶을 심각하게 저하시킨다. 소뇌 운동실조 환자는 운동제어 과정에서 부적절한 폐회로 소뇌 반응으로 인해 운동 명령이 제한된다. 본 논문에서는 최근 뇌-컴퓨터 인터페이스 기술을 이용하여 소뇌의 이상으로 인한 운동실조 환자들이 외부기기를 제어할 수 있도록 운동상상 기반의 뇌파의 특성을 분석하고 이를 이용한 뇌-컴퓨터 인터페이스 기법을 제안한다. 뇌파 기반의 뇌-컴퓨터 인터페이스의 효용성을 검증하기 위하여 소뇌 운동실조 환자와 정상인 그룹에서 운동상상에 따른 뮤밴드 파워를 조절하는 능력을 비교하였다. 이를 통하여 소뇌 운동실조 환자에의 뇌-컴퓨터 인터페이스의 가능성을 보여준다.