• Journal of Korean Neurosurgical Society
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• 제55권5호
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• pp.244-247
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• 2014

Objective : The aim of this study was to evaluate the microanatomy and histological features of the central myelin in the root exit zone of facial nerve. Methods : Forty facial nerves with brain stem were obtained from 20 formalin fixed cadavers. Among them 17 facial nerves were ruined during preparation and 23 root entry zone (REZ) of facial nerves could be examined. The length of medial REZ, from detach point of facial nerve at the brain stem to transitional area, and the thickness of glial membrane of central myelin was measured. We cut brain stem along the facial nerve and made a tissue block of facial nerve REZ. Each tissue block was embedded with paraffin and serially sectioned. Slices were stained with hematoxylin and eosin (H&E), periodic acid-Schiff, and glial fibrillary acid protein. Microscopy was used to measure the extent of central myelin and thickness of outer glial membrane of central myelin. Thickness of glial membrane was examined at two different points, the thickest area of proximal and distal REZ. Results : Special stain with PAS and GFAP could be differentiated the central and peripheral myelin of facial nerve. The length of medial REZ was mean 2.6 mm (1.6-3.5 mm). The glial limiting membrane of brain stem is continued to the end of central myelin. We called it glial sheath of REZ. The thickness of glial sheath was mean $66.5{\mu}m(40-110{\mu}m$) at proximal REZ and $7.4{\mu}m(5-10{\mu}m$) at distal REZ. Conclusion : Medial REZ of facial nerve is mean 2.6 mm in length and covered by glial sheath continued from glial limiting membrane of brain stem. Glial sheath of central myelin tends to become thin toward transitional zone.

• Biomolecules & Therapeutics
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• 제25권3호
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• pp.231-238
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• 2017

Myelin is a specialized structure of the nervous system that both enhances electrical conductance and insulates neurons from external risk factors. In the central nervous system, polarized oligodendrocytes form myelin by wrapping processes in a spiral pattern around neuronal axons through myelin-related gene regulation. Since these events occur at a distance from the cell body, post-transcriptional control of gene expression has strategic advantage to fine-tune the overall regulation of protein contents in situ. Therefore, many research interests have been focused to identify RNA binding proteins and their regulatory mechanism in myelinating compartments. Fragile X mental retardation protein (FMRP) is one such RNA binding protein, regulating its target expression by translational control. Although the majority of works on FMRP have been performed in neurons, it is also found in the developing or mature glial cells including oligodendrocytes, where its function is not well understood. Here, we will review evidences suggesting abnormal translational regulation of myelin proteins with accompanying white matter problem and neurological deficits in fragile X syndrome, which can have wider mechanistic and pathological implication in many other neurological and psychiatric disorders.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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• pp.14-23
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• 2002

The nervous system consists of two types of cells, which are neurons and glial cells. Among the glial cells, oligodendrodendrocytes and schwann cells form myelin sheaths in the central nervous system (CNS) and the peripheral nervous system (PNS), respectively. The major function of myelin in vertebrates is to insulate axonal and help action potential travel faster.(omitted)

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.736-740
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• 2008

The interaction of myelin basic protein (MBP) from bovine central nervous system with divalent calcium ion was studied by isothermal titration calorimetry at 27 ${^{\circ}C}$ in aqueous solution. The extended solvation model was used to reproduce the enthalpies of $Co^{2+}$-MBP interaction over the whole $Co^{2+}$ concentrations. The solvation parameters recovered from the solvation model were attributed to the structural change of MBP due to the metal ion interaction. It was found that there is a set of three identical and noninteracting binding sites for $Co^{2+}$ ions. The association equilibrium constant is 0.015 ${\mu}M^{-1}$. The molar enthalpy of binding is $\Delta$H = −14.60 kJ $mol^{-1}$.

• Investigative Magnetic Resonance Imaging
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• 제25권3호
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• pp.189-192
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• 2021

Anti-myelin oligodendrocyte glycoprotein (anti-MOG) syndrome is an immune-mediated inflammatory condition of the central nervous system, which usually involves spinal cord and optic nerves. Herein, we studied the case of a 57-year-old female patient who presented with acute/subacute symptoms of sphincter dysfunction, paraparesis, and ocular pain. The patient was diagnosed with anti-MOG syndrome with findings resembling snake-eye appearance (SEA), characterized by nearly symmetrical round high signal intensity lesions located at anterior horns (gray matter) on T2-weighted image.

• Journal of Nutrition and Health
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• 제40권2호
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• pp.130-137
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• 2007

Myelin basic protein (MBP), a major structural protein of the myelin, is thought to be important for the maintenance of myelin in the central nervous system (CNS). We investigated the effect of maternal folic acid nutritional status on the folate level and the synthesis of MBP in the offspring. In order to test this hypothesis, female Sprague-Dawley rats were fed either folic acid sufficient (8 mg/kg diet) or deficient (0 mg/kg diet) diet from 2 wks prior to the mating throughout the entire pregnancy, lactation and weaning period. We examined plasma folate level by the radioimmunoassay and homocysteine level by HPLC, respectively. The MBP expression was measured by the western blot analysis. The maternal folic acid deficiency decreased plasma folate level with a concomitant increase in plasma homocysteine level in their offspring. The maternal folic acid deficiency decreased hepatic levels of SAM and SAM/SAH ratio with a concomitant increase in hepatic levels of SAH and the MBP expression of spinal cord in their offspring at 7 wks of age. These results suggest that maternal folic acid nutritional status affect plasma folate and homocysteine level in their offspring. Moreover, the maternal folic acid deficiency mi호t inhibit the MBP expression of the spinal cord and disrupt many other vital CNS reactions in their offspring.

• Clinical and Experimental Pediatrics
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• 제64권3호
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• pp.103-110
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• 2021

Inflammatory or immune-mediated demyelinating central nervous system (CNS) syndromes include a broad spectrum of clinical phenotype and different overlapping diseases. Antibodies against myelin oligodendrocyte glycoprotein (MOG-Ab) have been found in some cases of these demyelinating diseases, particularly in children. MOG-Ab is associated with a wider clinical phenotype not limited to neuromyelitis optica spectrum disorder, with most patients presenting with optic neuritis, acute disseminated encephalomyelitis (ADEM) or ADEM-like encephalitis with brain demyelinating lesions, and/or myelitis. Using specific cell-based assays, MOG-Ab is becoming a potential biomarker of inflammatory demyelinating disorders of the CNS. A humoral immune reaction against MOG was recently found in monophasic diseases and recurrent/multiphasic clinical progression, particularly in pediatric patients. This review summarizes the data regarding MOG-Ab as an impending biological marker for discriminating between these diverse demyelinating CNS diseases and discusses recent developments, clinical applications, and findings regarding the immunopathogenesis of MOG-Ab-associated disorders.

• 한국동물학회지
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• 제33권4호
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• pp.454-460
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• 1990

Acrylamide의 신경독성에 대해 조사하기 위하여 초기운동실조증이 유도된 생쥐의 신경계에 대한 Acrylamide의 영향을 관찰한 결과, 중추 및 말초신경조직에 있어서의 손상이 보여 척수의 전반적 공포현상, 신경원 및 신경교의 세포손상 그리고 말초신경섬유의 퇴행현상들이 보였다. 또한 이들에 대한 미세구조적 관찰에 의하여 신경원에서의 비정상적 미토콘드리아 및 척수전근 섬유에서의 수초의 균혈화 현상등이 야기됨을 알았으며 좌골신경에서의 수초의 부분적 붕괴 및 축삭형질내의 퇴행현상들도 보였다. 위와 같은 실험결과는 Acrylamide로 인한 중독의 영향이 말초신경장애의 증상으로 나타나나 최초의 신경독성효과는 중추 및 말초신경계에 대해 거의 유사한 시기에 작용함을 시사한다.

• 대한의생명과학회지
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• 제28권4호
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• pp.290-297
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• 2022

Through previous studies, the central nervous system (CNS) was collected by dividing the scuttle fly into larval, pupa, and adult stages by developmental stage, and the morphological characteristics were observed. In situ hybridization (ISH) using the collected central nervous system, it was possible to confirm the location and extent of expression of the neurotransmitter corazonin (Crz) at each stage of development. In this study, paraffin specimens were prepared using central nervous system tissues of 3rd instar larval stage of scuttle fly, which had completed in situ hybridization, and general histochemical staining (hematoxylin-eosin, H-E) and special histochemical staining (luxol fast blue-cresyl violet) was performed to observe the histological and cytological morphology characteristics of corazonin neurons. As a result, a variety of nerve cell body existed between many myelin sheath. The corazonin neurons compose cortex of central nervous system with other neurons congregating in this tissue and show larger cell body relatively in neurohistochemical analysis.

• Journal of Preventive Medicine and Public Health
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• 제20권2호
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• pp.236-246
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• 1987

n-Hexane and benzene are organic compounds which have been widely used as industrial solvents. However, they are also increasingly recognized as important pollutants in working environment. The purpose of this study is tp analyze neurotoxicity of benzene and n-hexane. In this study, tibial nerve of Sprague-Dawley rats were observed after exposing them to two different concentrations of these compounds (6000 ppm of n-hexane and 2000 ppm of benzene) which were known to be the levels to cause subacute toxicity for the three different periods; two weeks, four weeks, and six weeks. The following results were obtained from the analysis of variance, Duncan's multiple comparison test, and regression analysis: 1) Myelin sheath thickness of nerve fiber for two n-hexane exposed groups (four weeks and six weeks) were both reduced compared with the control group and the benzene exposed group. 2) There were positive relationships between nerve fiber diameter and myelin sheath thickness for both exposed and control groups. 3) There was no significant difference in myelin sheath thickness from equal diameter nerve fibers between benzene exposed group and control group, but the greater number of thin myelin sheath were observed for n-hexane exposed group compared with control group. Thus, it is concluded that n-hexane tends to reduce the rate of growth of nerve fiber more than the benzene and control group. While these results shed light on understanding the effects of benzene and n-hexane, the duration of exposure was not long enough to apply these results to real working environments. In addition, to further understand the mechanims of nerve degeneration caused by organic solvents, both epidemiological and biochemical studies should accompanied by this kind of study.