1.Study on the Effect of Vitamin E Against Methylmercury-induced Neurotoxicity in Cultured Spinal Motor Neurons .
Yeun Tai CHUNG ; Seung Taeck PARK
Korean Journal of Physical Anthropology 1996;9(1):109-116
In order to investigate the neurotoxic effect of methylmercury (MM) on cultured mouse spinal motoneuron cell line, NSC-19, neurotoxic effect of MM was evaluated by MTT assay after neurons were incubated with various concentrations of methylmercuric chloride (MMC) for 24 hours. In addition, neuroprotective effect of vitamin E against MMC-induced neurotoxicity was examined by MTT assay and neurofilament enzymeimmunoassay (EIA) in these cultures. The results were as follows : 1. MTT50 value was a concentration of 20µM methylmercuric chloride. 2. Methylmercuric chloride was toxic on cultured spinal motor neurons, NSC-19 cells in a time-and dose-dependent manner by severe decrease of cell viability. 3. Methylmercuric chloride induced the decrease of cell number and the loss of neuritis on these cultures. 4. Vitamin E remarkably increased the viabilily of cultured neurons damaged by methylmercury-induced neurotoxicity at a concentration of 250µM vitamin E. From above the results, it is suggested that methylmercury induces severe toxic effect on cultured mouse spinal motor neurons, NSC-19 cells, and the selective antioxidants such as vitamin E are effective in the neurotoxicity induced by methylmercury in these cultures.
Animals
;
Antioxidants
;
Cell Count
;
Cell Culture Techniques
;
Cell Line
;
Cell Survival
;
Intermediate Filaments
;
Mice
;
Motor Neurons*
;
Neuritis
;
Neurons
;
Neuroprotective Agents
;
Vitamin E*
;
Vitamins*
2.Effect of Midkine (MK) on Cultured Spinal Motor Neurons Damaged by Oxidative Stress.
Seung Taeck PARK ; Yeun Tai CHUNG
Korean Journal of Physical Anthropology 1996;9(1):101-107
To evaluate the effect of midkine (MK), neurotrophic factor on cultured mouse spinal motor neuron, NSC-19 which was inhibited by glucose oxidase (GO)-induced oxygen radicals, MTT assay and neurofilament enzymeimmunoassay were carried out after NSC-19 cells were preincubated with various concentrations of midkine for 2 hours prior to exposure of glucose oxidase. The results were as follows : 1. MK increased the rate of cell viability and neurofilamental development in a dose-dependent manner on motoneurons inhibited by glucose oxidase-induced oxygen radicals. 2. MTT50 value was 25 mU/ml GO. 3. GO-induced oxygen radicals were toxic on cultured motor neurons in a time and dose-dependent manner. 4. GO-induced oxygen radicals induced the decrease of cells in number and the loss of neurites in cultured mouse spinal motor neurons. From above the results, it is concluded that oxygen radicals are toxic in cultured mouse spinal motor neurons, and selective neurotrophic factors such as MK enhance the viability of motor neurons inhibited by oxygen radicals.
Animals
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Cell Survival
;
Glucose
;
Glucose Oxidase
;
Intermediate Filaments
;
Mice
;
Motor Neurons*
;
Nerve Growth Factor
;
Nerve Growth Factors
;
Neurites
;
Oxidative Stress*
;
Reactive Oxygen Species
3.Effect of Allopurinol on Methylmercuric Chloride in Cultured O1igodendrocytes.
Seung Taeck PARK ; Byung Rim PARK ; Yeun Tai CHUNG
Korean Journal of Physical Anthropology 1996;9(2):183-188
To elucidate the neurotoxic mechanism of methylmercury on cultured bovine oligodendrocytes, neurotoxic effect was estimated by MTT assay after cultures were exposed to various concentrations of methylmercuric chloride (MMC). In addition, neuroprotective effect of antioxidant, allopurinol agonist MMC-induced neurotoxicity was examined on these cultures. Exposure of cultured bovine oligodendrocytes to MMC showed less than 50% of the cell viability 24 hours after treatment with 35µM of MMC. And also, allopurinol blocked the neurotoxicity induced by MMC on these cultures. These results suggest that oxygen radicals involve in MMC-mediated neurotoxicity, and also seletive antioxidants such as allopurinol are effective in blocking the neurotoxicity induced by MMC on cultured bovine oligodendrocytes.
Allopurinol*
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Antioxidants
;
Cell Survival
;
Neuroprotective Agents
;
Oligodendroglia
;
Reactive Oxygen Species
4.A study on the cytotoxic effect of some heavy metals on the rat liver cell.
Yeun Tai CHUNG ; Min Kyu CHOI ; Seung Taeck PARK ; Jeong Joong KIM
Korean Journal of Anatomy 1991;24(1):102-111
No abstract available.
Animals
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Liver*
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Metals, Heavy*
;
Rats*
5.Two Cases of Graves Disease Associated The Empty Sella Syndrome
Yeun Jong CHOI ; Hong Seung KIM ; Eui Ryun PARK ; Young Gu SHIN ; Choon Hee CHUNG
Journal of Korean Society of Endocrinology 1996;11(4):517-522
The empty sella syndrome is characterized by obesity, frequent pregnancy, headache and high blood pressure, but its exact cause remains unknown. Usually the incomplete diaphragmatic sella has been considered as the cause of the empty sella syndrome, but some authors recently have suggested that the antipituitary antibody way be related to development of pituitary atrophy and the pituitary empty sella syndrome, and thus it may be clinically useful as screening test for the empty sella syndrome. We experienced two empty sella syndromes associated Graves disease and applied the antipituitary antibody as the diagnostic tool of the empty sella syndrome. But none of this two patients had antipituitary antibody and we report these cases with reviews of literatures.
Atrophy
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Empty Sella Syndrome
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Graves Disease
;
Headache
;
Humans
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Hypertension
;
Mass Screening
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Obesity
;
Pregnancy
6.A Case of Treatment of Acute Occlusion Complicating Percutaneous Transluminal Coronary Angioplasty.
Yeun Sun KIM ; Jin Iee CHUNG ; Bo In CHUNG ; Jae Woong CHOI ; In Seok CHOI ; Seung Woon AHN ; Eak Kyun SHIN
Korean Circulation Journal 1991;21(5):932-939
Management of unstable angina has evolved progressively. Although coronary angioplasty has recently shown to be relatively safe and effective treatment strategy for unstable angina, aute occlusion due to intracoronary thrombus accumulation during or immediately after coronary angioplasty remains to be one of the most common serious complication of this procedure. Intracoronary urokinase has been used to treat flow-limiting intracoronary thrombus accumulation that complicated initial successful percutaneous transluminal coronary angioplasty(PTCA) in unstable angina patient, which made the patient stablilzed. Thus in patient with flow-limiting intracoronary thrombus accumulation complicating PTCA, intracoronary urokinase proved to be highly effective in restoring vessel patency and preventing acute myocardial infarction. We report a case of successful revascularization with intracoronary infusion of urokinase in patient with intracoronary thrombus accumulation that complicated PTCA.
Angina, Unstable
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Angioplasty
;
Angioplasty, Balloon, Coronary*
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Humans
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Myocardial Infarction
;
Thrombosis
;
Urokinase-Type Plasminogen Activator
7.Effect of Allopurinol on Methylmercuric Chloride in Cultured O1igodendrocytes.
Seung Taeck PARK ; Yeun Ja MUN ; Jae Min OH ; Jung Joong KIM ; Min Kyu CHOI ; Jae Han SHIM ; Kye Taek LIM ; Yeun Tai CHUNG
Korean Journal of Physical Anthropology 1996;9(2):189-195
In order to examine the neurotoxic mechanism of oxygen radicals on cultured bovine oligodendrocytes, cytoxic effect of oxygen radicals was examined when cultures were treated with various concentrations of xanthine oxidase (XO) and hypoxanthine (HX) in culture medium. In addition, the neuroprotective effect of iron-chelators against the neurotoxicity induced by oxygen radicals was evaluated by MTT assay. Cell viability was remarkably decreased in a time-dependent manner after exposure of cultured bovine oligodendrocytes to 20mU/ml XO and 0.1mM HX for 4 hours. In the neuroprotective effect of iron-chelators on oxidant-induced neurotoxicity, tetrakis (2-pyridylmethyl)ethylenediamine (TPEN) blocked the neurotoxicity induced by oxygen radicals, while DFX was not effective in blocking oxidant-induced neurotoxicity in these cultures. These results suggest that oxygen radicals are toxic in cultured bovine oligodendrocytes, and also selective iron-chelators such as TPEN are effective in blocking the neurotoxicity induced by oxygen radicals.
Allopurinol*
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Cell Survival
;
Hypoxanthine
;
Neuroprotective Agents
;
Oligodendroglia
;
Reactive Oxygen Species
;
Xanthine Oxidase
8.The peripatetic placenta(II).
Seung Ryoung KIM ; Jung Bae YOO ; Moon Il PARK ; Sung Ro CHUNG ; Yeun Young HWANG ; Hyung MOON ; Doo Sang KIM
Korean Journal of Perinatology 1991;2(2):1-9
No abstract available.
9.We Anesthetized a Patient with Unexpected Pheochromocytoma, Diagnosed during Operation: 1 case report.
Seung Ho KANG ; Yeun Gin CHUNG ; Chun Ik JANG
Korean Journal of Anesthesiology 1997;32(1):139-143
Pheochromocytoma is a tumor which secretes catecholamine and produces remarkable hemodynamic changes during the perioperative period. It is reported that in cases where a patient with undiagnosed pheochromocytoma is operated on, the mortality rate can reach 25% to 50%. The subject in this study was a 55-year-old female patient who was diagnosed having a retroperitoneal mass which looked like a neurogenic tumor. During the manipulation, serious hypertension and tachycardia were developed. The authors at that time suspected a pheochromocytoma, interrupted the operation, and after insertion of arterial line and sodium nitroprusside infusion, the rest of the operation was restarted. After the extirpation of the tumor, as the patient suffered serious hypotension, the concentration of the inhalation agent was reduced, ephedrine was injected, the proper amount of fluid and blood were administered, and, as a result, the operation was carried out safely, and postoperative course was unremarkable.
Ephedrine
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Female
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Hemodynamics
;
Humans
;
Hypertension
;
Hypotension
;
Inhalation
;
Middle Aged
;
Mortality
;
Nitroprusside
;
Perioperative Period
;
Pheochromocytoma*
;
Tachycardia
;
Vascular Access Devices
10.Development of an RNA sequencing panel to detect gene fusions in thyroid cancer
Dongmoung KIM ; Seung-Hyun JUNG ; Yeun-Jun CHUNG
Genomics & Informatics 2021;19(4):e41-
In addition to mutations and copy number alterations, gene fusions are commonly identified in cancers. In thyroid cancer, fusions of important cancer-related genes have been commonly reported; however, extant panels do not cover all clinically important gene fusions. In this study, we aimed to develop a custom RNA-based sequencing panel to identify the key fusions in thyroid cancer. Our ThyChase panel was designed to detect 87 types of gene fusion. As quality control of RNA sequencing, five housekeeping genes were included in this panel. When we applied this panel for the analysis of fusions containing reference RNA (HD796), three expected fusions (EML4-ALK, CCDC6-RET, and TPM3-NTRK1) were successfully identified. We confirmed the fusion breakpoint sequences of the three fusions from HD796 by Sanger sequencing. Regarding the limit of detection, this panel could detect the target fusions from a tumor sample containing a 1% fusion-positive tumor cellular fraction. Taken together, our ThyChase panel would be useful to identify gene fusions in the clinical field.