• Journal of Yeungnam Medical Science
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• 제16권1호
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• pp.125-130
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• 1999

저자들은 최근 25세 여자 환자로 뚜렷한 가족력이 없으면서 3-4세경부터 발생한 근육의 강직현상과 현저한 근비대소견이 있는 환자를 경험하였다. 임상적으로 타진성 근긴장증을 보이고 전기생리적 검사로 새끼손가락 외향근에서의 운동과 반복신경자극에서 복합근육활동전위의 감소를 보였으며, 이두박근의 근생검 소견상 용적이 증가된 근섬유와 중심핵화현상이 관찰되었다. 환자는 mexiletin 경구 투여후 근육의 강직현상이 다소 호전되었다. 이에 문헌고찰과 함께 Becker형 선천성 근긴장증 1례를 보고하는 바이다.

• The Korean Journal of Physiology and Pharmacology
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• 제21권4호
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• pp.439-447
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• 2017

Myotonia congenita (MC) is a genetic disease that displays impaired relaxation of skeletal muscle and muscle hypertrophy. This disease is mainly caused by mutations of CLCN1 that encodes human skeletal muscle chloride channel (CLC-1). CLC-1 is a voltage gated chloride channel that activates upon depolarizing potentials and play a major role in stabilization of resting membrane potentials in skeletal muscle. In this study, we report 4 unrelated Korean patients diagnosed with myotonia congenita and their clinical features. Sequence analysis of all coding regions of the patients was performed and mutation, R47W and A298T, was commonly identified. The patients commonly displayed transient muscle weakness and only one patient was diagnosed with autosomal dominant type of myotonia congenita. To investigate the pathological role of the mutation, electrophysiological analysis was also performed in HEK 293 cells transiently expressing homo-or heterodimeric mutant channels. The mutant channels displayed reduced chloride current density and altered channel gating. However, the effect of A298T on channel gating was reduced with the presence of R47W in the same allele. This analysis suggests that impaired CLC-1 channel function can cause myotonia congenita and that R47W has a protective effect on A298T in relation to channel gating. Our results provide clinical features of Korean myotonia congenita patients who have the heterozygous mutation and reveal underlying pathophyological consequences of the mutants by taking electrophysiological approach.

• Annals of Clinical Neurophysiology
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• 제11권2호
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• pp.67-70
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• 2009

Colchicine is widely used in the treatment of gouty arthritis, and chronic use of colchicine can cause vacuolar myopathy. We report colchicine-induced myopathy with electrophysiological myotonia in a patient with gouty arthritis. A 86-year-old man with gouty arthritis presented with progressive proximal weakness and gait disturbance. Electrophysiological finding showed myotonic myopathy and muscle biopsy revealed a vacuolar myopathy. His symptoms soon resolved with the discontinuation of colchicine.

• Molecules and Cells
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• 제37권3호
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• pp.202-212
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• 2014

ClC-1 is a member of a large family of voltage-gated chloride channels, abundantly expressed in human skeletal muscle. Mutations in ClC-1 are associated with myotonia congenita (MC) and result in loss of regulation of membrane excitability in skeletal muscle. We studied the electrophysiological characteristics of six mutants found among Korean MC patients, using patch clamp methods in HEK293 cells. Here, we found that the autosomal dominant mutants S189C and P480S displayed reduced chloride conductances compared to WT. Autosomal recessive mutant M128I did not show a typical rapid deactivation of Cl- currents. While sporadic mutant G523D displayed sustained activation of $Cl^-$ currents in the whole cell traces, the other sporadic mutants, M373L and M609K, demonstrated rapid deactivations. $V_{1/2}$ of these mutants was shifted to more depolarizing potentials. In order to identify potential effects on gating processes, slow and fast gating was analyzed for each mutant. We show that slow gating of the mutants tends to be shifted toward more positive potentials in comparison to WT. Collectively, these six mutants found among Korean patients demonstrated modifications of channel gating behaviors and reduced chloride conductances that likely contribute to the physiologic changes of MC.

• 한국임상수의학회지
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• 제37권5호
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• pp.273-277
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• 2020

A 12-year-old, female Maltese was referred with uncontrolled hyperadrenocorticism (HAC). Despite well management of HAC through treatment with trilostane and serial monitoring with ACTH stimulation tests for over three years, stiffness of the neck and limbs progressively worsened over time. Neurological test was performed, which showed no abnormalities of cranial nerves. Proprioception was delayed but the cause appeared to be due to stiffness of limb muscles. Muscle tone had increased over time and stiffness had worsened to the extent where it made walking difficult. MRI scans showed no orthopedic or spinal diseases, and pituitary microadenoma was confirmed with pituitary gland measurement of 6 × 6.4 × 4.5 mm (H × W × L). Electromyography presented random discharges with fluctuating amplitude and frequency, which were consistent with myotonic discharges. There were no improvements of myotonic signs despite treatment for HAC with trilostane. Supplementation of L-carnitine and coenzyme Q-10 to mitigate muscle stiffness, following diazepam and methocarbamol to help with muscle rigidity, failed to show any positive effect and the dog died a sudden death, 1,182 days after the initial visit.

• Journal of Interdisciplinary Genomics
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• 제3권2호
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• pp.25-29
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• 2021

Myotonic muscular dystrophy is a disease characterized by progressive muscle weakness with myotonia and multiorgan involvement. Two subtypes have been recognized; each subtype is caused by nucleotide repeat expansion. So far, there has been no cure for myotonic muscular dystrophy. In this article, we introduce ongoing clinical trials for new drugs to modify disease course by correcting genetic derangement or its downstream in myotonic dystrophy type 1.

• 대한신경과학회지
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• 제36권4호
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• pp.402-404
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• 2018

• 한국유전체학회:학술대회논문집
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• 한국유전체학회 2002년도 The 11th Korea Genome Conference
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• pp.41.1-41.1
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• 2002

• Molecules and Cells
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• 제37권6호
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• pp.435-440
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• 2014

Hemodynamic shear stress, the frictional force acting on vascular endothelial cells, is crucial for endothelial homeostasis under normal physiological conditions. When discussing blood flow effects on various forms of endothelial (dys)function, one considers two flow patterns: steady laminar flow and disturbed flow because endothelial cells respond differently to these flow types both in vivo and in vitro. Laminar flow which exerts steady laminar shear stress is atheroprotective while disturbed flow creates an atheroprone environment. Emerging evidence has provided new insights into the cellular mechanisms of flowdependent regulation of vascular function that leads to cardiovascular events such as atherosclerosis, atherothrombosis, and myocardial infarction. In order to study effects of shear stress and different types of flow, various models have been used. In this review, we will summarize our current views on how disturbed flow-mediated signaling pathways are involved in the development of atherosclerosis.

• Journal of the Optical Society of Korea
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• 제15권4호
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• pp.373-379
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• 2011

Current therapeutic methods for suppressing muscle spasticity are intensive functional training, surgery, or pharmacological interventions. However, these methods have not been fully supported by confirmed efficacy due to the aggravation of the muscle spasticity in some patients. In this study, a combined system was developed to treat with a low-level laser and to monitor the region of the treatment using an optical spectroscopic probe that measures oxygen saturation and deoxygenation during low-level laser therapy (LLLT). The evaluation of the wavelength dependence for LLLT was performed using a Monte Carlo simulation and the results showed that the greatest amount of heat generation was seen in the deep tissue at ${\lambda}$ = 830 nm. In the oxy- and deoxygenation measurements during and after the treatment, oxygen-Hb concentration was significantly increased in the laser-irradiated group when compared to the control group. These findings suggest that LLLT using ${\lambda}$ = 830 nm may be of benefit in accelerating recovery of muscle spasticity. The combined system that we have developed can monitor the physiological condition of muscle spasticity during the laser treatment in real time and may also be applied to various myotonia conditions such as muscle fatigue, back-pain treatment/monitoring, and ulcer due to paralysis.