• Journal of Korean Neurosurgical Society
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• v.54 no.2
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• pp.118-124
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• 2013

Objective : Subthalamic nucleus (STN) deep brain stimulation (DBS) is an effective treatment of choice for patients with advanced idiopathic Parkinson's disease (PD) who have motor complication with medication. The objectives of this study are to analyze long-term follow-up data of STN DBS cases and to identify the factors related to outcomes. Methods : Fifty-two PD patients who underwent STN DBS were followed-up for more than 3 years. The Unified Parkinson's Disease Rating Scale (UPDRS) and other clinical profiles were assessed preoperatively and during follow-up. A linear regression model was used to analyze whether factors predict the results of STN DBS. We divided the study individuals into subgroups according to several factors and compared subgroups. Results : Preoperative activity of daily living (ADL) and the magnitude of preoperative levodopa response were shown to predict the improvement in UPDRS part II without medication, and preoperative ADL and levodopa equivalent dose (LED) were shown to predict the improvement in UPDRS part II with medication. In UPDRS part III with medication, the magnitude of preoperative levodopa response was a predicting factor. Conclusion : The intensity of preoperative levodopa response was a strong factor for motor outcome. And preoperative ADL and LED were strong factors for ADL improvement. More vigorous studies should be conducted to elucidate how levodopa-induced motor complications are ameliorated after STN DBS.

• The Journal of Korean Medicine
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• v.25 no.3
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• pp.67-77
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• 2004

Objectives : Many studies have reported that acupuncture analgesia was mediated through the activation of peripheral and central opioid receptors. However, there has been little electrophysiological study on the adrenergic mechanism of acupuncture analgesia in chronic inflammatory and neuropathic pain. The present study was undertaken to elucidate the role of adrenoceptors in the production of acupuncture analgesia in the chronic pain model. Methods : In the rat with chronic inflammation and nerve injury, dorsal horn cell (DHC) responses to afferent C fiber stimulation were used as a pain index and changes in electroacupuncture (EA) analgesia were recorded before and after intravenous administration of selective adrenoceptor antagonists. EA stimulations (2Hz, 0.5msec, 3mA) were applied to the contralateral Zusanli point for 30 min. Results : EA stimulation induced long-lasting inhibition of DHC responses in the rat with chronic inflammation and nerve injury. In both models of inflammation and neuropathic pain, α-adrenoceptor antagonist (phentolamine) significantly attenuated an inhibitory effect of EA on DHC responses. Selective α2-adrenoceptor antagonist (yohimbine) also had a similar suppressive action on DHC responses to that of phentolamine. However, β-adrenoceptor antagonist (propranolol) did not have any inhibitory effect on DHC responses in either model of chronic pain. Conclusions : These experimental findings suggest that in rats with chronic pain, EA stimulation with low frequency and high intensity produced an analgesic effect which was mediated through an activation of α2-adrenoceptors.

• Journal of Acupuncture Research
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• v.18 no.6
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• pp.215-224
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• 2001

Objcetive : Neuropathic pain sometimes arises from a partial peripheral nerve injury. This kind of pain is usually accompanied by spontaneous burning pain, allodynia and hyperalgesia. It has been well known that acupuncture is effective to the pain control from ancient time in Asia. However, it is not clear whether acupuncture can control neuropathic pain. The aim of the present study is to examine if acupuncture stimulation may be effective to the mechanical allodynia in a rat model of neuropathic pain. Methods : To produce neuropathic pain, under sodium pentobarbital anesthesia, the right superior caudal trunk was resected between the S3 and S4 spinal nerves. After the neuropathic surgery, we examined if the animals exhibited the behavioral signs of mechanical allodynia. The mechanical allodynia was assessed by stimulating the tail with von Frey hair (bending force : 2.0g). three or 6 weeks after the neuropathic surgery, acupuncture stimulation was delivered to Houxi (SI 3) as the following parameters (2HZ frequency, 0.07mA intensity and 3msec duration) for 30 minutes. Results : The stimulation of Houxi (SI 3) acupoint relieved the behavioral signs of mechanical allodynia. Conclusion : Our results suggest that acupuncture can control the mechanical allodynia of neuropathic pain.

• Physical Therapy Korea
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• v.21 no.4
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• pp.1-8
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• 2014

Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers low-intensity direct current to cortical areas, thereby facilitating or inhibiting spontaneous neuronal activity. This study was designed to investigate changes in various sensory functions after tDCS. We conducted a single-center, single-blinded, randomized trial to determine the effect of a single session of tDCS with the current perception threshold (CPT) in 50 healthy volunteers. Nerve conduction studies were performed in relation to the median sensory and motor nerves on the dominant hand to discriminate peripheral nerve lesions. The subjects received anodal tDCS with 1 mA for 15 minutes under two different conditions, with 25 subjects in each groups: the conditions were as follows tDCS on the primary motor cortex (M1) and sham tDCS on M1. We recorded the parameters of the CPT a with Neurometer$^{(R)}$ at frequencies of 2000, 250, and 5 Hz in the dominant index finger to assess the tactile sense, fast pain and slow pain, respectively. In the test to measure CPT values of the M1 in the tDCS group, the values of the distal part of the distal interphalangeal joint of the second finger statistically increased in all of 2000 Hz (p=.000), 250 Hz (p=.002), and 5 Hz (p=.008). However, the values of the sham tDCS group decreased in all of 2000 Hz (p=.285), 250 Hz (p=.552), and 5 Hz (p=.062), and were not statistically significant. These results show that M1 anodal tDCS can modulate sensory perception and pain thresholds in healthy adult volunteers. The study suggests that tDCS may be a useful strategy for treating central neurogenic pain in rehabilitation medicine.

• Physical Therapy Rehabilitation Science
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• v.3 no.2
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• pp.112-118
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• 2014

Objective: The purpose of this study was to investigate the effects of an exercise with and without neuromuscular electrical stimulation (NMES) of the quadriceps femoris muscle, on strength, pain, and weight distribution in patients with knee instability post surgery. Design: Randomized controlled trial. Methods: Twenty patients in the early stage of rehabilitation after knee surgery were recruited as subjects and were randomly divided into either experimental group (exercise combined with NMES) (n=10) or control group (n=10). Both groups received strength training of the lower limb for 20 min/day, 5 days/week for 4 weeks. The experimental group used NMES for unilateral quadriceps femoris training with incremental increases in the intensity of isometric contraction over 4 weeks. Outcome measurements were assessed using the digital manual muscle testing, 30-chair stand test (30CST), numeric pain rating scale (NPRS) and weight distribution using the foot analyzer before and after 4 weeks of training. Results: After the 4-week intervention, knee extensor strength increased significantly in the experimental group post intervention (p<0.05), and there was a significant improvement in the experimental group compared with the control group (p<0.05). The 30CST and NPRS scores improved significantly in the experimental group compared to the control group (p<0.05), and there was a significant difference between the two groups (p<0.05). Weight distribution was significantly improved in the experimental group compared with the control group, (p<0.05), but there was no significant difference in improvement between the two groups. Conclusions: This study showed that NMES combined with strengthening exercises of the lower limbs is effective in improving lower limb pain and strength in patients with instability after knee surgery.

• The Journal of Korean Physical Therapy
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• v.36 no.1
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• pp.39-44
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• 2024

Purpose: Cybersickness is a type of motion sickness induced by virtual reality (VR) or augmented reality (AR) environments that presents symptoms including nausea, dizziness, and headaches. This study aimed to investigate how cathodal transcranial direct current stimulation (tDCS) alleviates motion sickness symptoms and modulates brain activity in individuals experiencing cybersickness after exposure to a VR environment. Methods: This study was performed on two groups of healthy adults with cybersickness symptoms. Subjects were randomly assigned to receive either cathodal tDCS intervention or sham tDCS intervention. Brain activity during VR stimulation was measured by 38-channel functional near-infrared spectroscopy (fNIRS). tDCS was administered to the right temporoparietal junction (TPJ) for 20 minutes at an intensity of 2mA, and the severity of cybersickness was assessed pre- and post-intervention using a simulator sickness questionnaire (SSQ). Result: Following the experiment, cybersickness symptoms in subjects who received cathodal tDCS intervention were reduced based on SSQ scores, whereas those who received sham tDCS showed no significant change. fNIRS analysis revealed that tDCS significantly diminished cortical activity in subjects with high activity in temporal and parietal lobes, whereas high cortical activity was maintained in these regions after intervention in subjects who received sham tDCS. Conclusion: These findings suggest that cathodal tDCS applied to the right TPJ region in young adults experiencing cybersickness effectively reduces motion sickness induced by VR environments.

• The Korean Journal of Physiology
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• v.27 no.2
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• pp.185-197
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• 1993

The rostral ventrolateral medulla (RVLM) includes vasopressor neurons, which transmit activation signals to the intermediolateral nucleus (IML) of the spinal cord, where the preganglionic sympathetic nucleus is located, to raise arterial blood pressure (BP). However, controversy exists as to the possible depressor area in the RVLM and the pathway involved. The present study persued evidence far the location of depressor neurons and the pathway by simultaneously observing changes in BP and the firing rate (FR) of cardiovascular neurons (CVNs) in the RVLM during the somatosympathetic reflex (SSR) elicited by peripheral nerve stimulation, since CVNs are known to contribute to the generation of the sympathetic nerve discharge. In 42 cats, anaesthetized with $\alpha-chloralose$, single unit recording was performed, using carbon filament electrodes inserted into the RVLM, enabling estimation of the post R wave unit histogram (PR-UNlT) and the spike triggered average of sympathetic nerve discharge (STA-SND), allowing identification of CVNs. Antidromic stimulation of spinal $T_2$ segment was followed to determine whether the identified CVN projects axonal endings to the spinal cord (reticulospinal neuron). The sciatic nerve was electrically stimulated at $A\delta-intensity$ (1 mA, 0.1 ms), 1 Hz and C-intensity (10 mA, 0.5 ms), 20 Hz to elicit the depressor, and pressor responses of the SSR, respectively. Simultaneous measurement of CVN firing rate was made. Experimental results are summarized as follows. 1) 20 out of 98 CVNs had axonal projections to the spinal cord and 17 out of 98 CVNs showed FR changes during SSR. 2) Response patterns of FR and BP during SSR were classified into 8 types. 3) These 8 different response patterns could be further classified into those from pressor and depressor neurons. These results demonstrate that some CVNs were identifiable as reticulospinal neurons responding to anti-dromic stimulation and that CVNs operating as depressor neurons as well as pressor neurons exist in the RVLM, both of which are involved with SSR mediation. Therefore, evidence was found that an independent depressor pathway might be involved in the mediation of SSR.

• Journal of Biomedical Engineering Research
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• v.38 no.4
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• pp.175-182
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• 2017

Microcurrent electrical stimulation(MES) has been used to accelerate recovery of atrophied skeletal muscle. However, convincing stimulation parameters for suppressing muscle atrophy due to injured sciatic nerve remains unclear. The objective of this study was to investigate the effective intensity of MES on restraining muscle atrophy with rat model underwent sciatic nerve injury(SNI). Twenty-5-week-old Sprague Dawley male rats were equally assigned to five groups : Control group(Control, CON, n = 4), Denervation group(Denervation, D, n = 4), Denervation with MES of $22{\mu}A$ group(Denervation + $22{\mu}A$, D+22, n = 4), Denervation with MES of $100{\mu}A$ group (Denervation + $100{\mu}A$, D+100 n = 4), Denervation with MES of $400{\mu}A$ group(Denervation + $400{\mu}A$, D+400, n = 4). To induce muscle atrophy, all rats in the D, D+22, D+100, and D+400 groups, were subjected to sciatic nerve injury on their right hindlimb and allowed to have 1 week of resting period. Following this period, rats underwent daily MES(60 min/ a day, 5times/1week) for 4 weeks. After that, we investigate morphological changes in muscle volume by using in vivo micro-computed tomography at week 0, 1, 3 and 5. After 5 weeks, the muscle volume had the highest value in D+400 group, and also noticeably increased in D+100 group compared to it in D group. The results of this study imply that MES with current intensities between $100-400{\mu}A$ can suppress muscle atrophy effectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.14 no.2
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• pp.69-80
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• 1986

In order to analyse the color preference quantitatively, specially with reference to the subjects in the age of twenties, 100 subjects(M=50, F=50) that unconsidered other factors were adopted and responded to 4 items of the questionaire. The item no. 1 was to investigate the most prefered color on the white background, no. 2 was to most preferred stimulation -level of lightness in the same hues, no. 3 was to most prefered color on 5 different backgrounds -grey, blue, pink, yellow, and yellow green-, and no. 4 was same as no. 3 but with different color-arrangement Materials for item 1 and 3 were made with transparent acryl-boards(30cm$\times$30cm), on which 16 color chips arranged on circle, for item 4 on lattice, and for item 2 with 16 white boards(8cm$\times$21cm), on which 7 color chips of different lightness-level arranged. Reflectance(Y) and color coordinate(x, y) of all color chips measured with color difference meter were transfered into wavelength(nm), exitation purity(%), and Munsell's value. The results may be summarized as follows: 1) Most prefered color was bluish green with wave1ength about 500nm. As increasing of exitation purity of color, more prefered. 2) When there were 7 different levels of lightness in the same hues, the relationship between the number of preference and the stimulation was inverted U-shaped. 3) With changing the background -color, the prefered colors were contrasting when backgrounds were low or high intensity-stimulation and familiar colors when backgrounds were medium intensity.

• Clinical Pain
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• v.18 no.1
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• pp.1-7
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• 2019

Objective: To investigate the cortical disinhibition in diabetic patients with neuropathic pain and without pain. In addition, we assessed the cortical disinhibition and pain relief after repetitive transcranial magnetic stimulation (rTMS). Method: We recruited diabetic patients with neuropathic pain (n = 15) and without pain (n = 15). We compared the TMS parameters such as motor evoked potential (MEP) amplitude, cortical silent period (CSP), intracortical inhibition (ICI %) and intracortical facilitation (ICF %) between two groups. Moreover, we evaluated the changes of pain and TMS parameters after five consecutive high frequency (10 Hz) rTMS sessions in diabetic patients with neuropathic pain. The neuropathic pain intensity (visual analog scale) and TMS parameters were assessed on pre-rTMS, post-rTMS 1day, and post-rTMS 5 day. Results: The comparison of the CSP, ICI % revealed significant differences between two groups (p<0.01). After rTMS sessions, the decrease in pain intensity across the three time points revealed a pattern of significant differences (p<0.01). The change of CSP and ICI % across the three test points revealed a pattern of significant differences (p<0.01). The ICI % revealed immediate increase after first rTMS application and significant increase after five rTMS application (p<0.01) in diabetic patients with neuropathic pain. The MEP amplitude and ICF % did not reveal any significant changes. Conclusion: Our findings demonstrate that cortical inhibition was decreased in diabetic patients with neuropathic pain compared with patients without pain. Furthermore, we also identified that five daily rTMS sessions restored the defective intracortical inhibition which related to improvement of neuropathic pain in diabetic patients.