• Title/Summary/Keyword: Choi Chi-won

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Fatty Acid Composition of Antarctic Toothfish Dissostichus mawsoni (남극이빨고기(Dissostichus mawsoni)의 지방산조성)

  • Lim, Chi-Won;Jo, Hyun-Su;Yeon, InJa;Seok, KyuJin;Choi, Seok-Gwan;Yoon, Na-Young;Shim, Kil-Bo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.45 no.6
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    • pp.579-585
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    • 2012
  • The proximate compositions and fatty acid profiles of Antarctic toothfish Dissostichus mawsoni that was caught in the southern Ross Sea (J, L) of the Antarctic Ocean were studied. The lipid contents of samples from J and L were 18.2 and 21.1%, respectively. The protein and ash contents were similar for samples J and L. The prominent fatty acids in the total lipids of the fish muscle were 18:1n-9, 16:1n-7, 16:0, 14:0, 18:1n-7, 20:5n-3 (eicosapentaenoic acid, EPA), and 22:6n-3 (docosahexaenoic acid, DHA). In addition, the total fatty acids of bycatch products in the toothfish stomachs (Pleuragramma antarcticum, Gerlachea australis, Pasiphaea sp., Trematomus eulepidotus, Chionodraco hamatus, Chionodraco myersi, and Neopagetopsis ionah) were determined. The prominent fatty acids in those species were 18:1n-9, 16:0, 14:0, DHA, EPA, and 18:1n-7.

Extraction Methods for Recovering Malachite Green and Leucomalachite Green (추출방법들에 의한 Malachite Green과 Leucomalachite Green 회수율)

  • Bae, Jin-Han;Yun, Young-Soo;Yoon, Sung-Ho;Choi, Kwang-Jin;Lee, Jeong-Seon;Lim, Chi-Won;Kim, Yeon-Kye;Park, Hee-Yeon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.1
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    • pp.13-19
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    • 2008
  • Malachite green (MG), a triphenylmethane dye, is carcinogenic, mutagenic, teratogenic, a respiratory toxin, and causes chromosomal fractures. It is not permitted for use as an aquaculture veterinary drug in a number of countries. Sensitive extraction methods for MG and leucomalachite green (LMG), which have long residence times in fish tissues, were developed. For LMG, the average recovery of liquid extraction (LE) ranged from 41.71 (yellowtail) to 71.60% (snakehead); the recovery of liquid-liquid extraction (LLE) was between 67.68 (yellowtail) and 83.68% (snakehead); and the average recovery of solid-phase extraction (SPE) ranged from 84.16 (yellowtail) to 92.92% (shrimp). The recovery of MG was less than 30% with SPE. However, the dye is found primarily as the colorless reduced leuco form in fish tissues.

A Study on the Radon Concentration in the Office (사무실 내 라돈 농도에 관한 연구)

  • Choi, Hyun Woo;Kim, Chi-Nyon;Won, Jong-Uk;Kim, Hong-Kwan;Roh, Jaehoon
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.26 no.3
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    • pp.334-341
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    • 2016
  • Objectives: This study is aimed at examining radon exposure in offices and the factors that can influence the concentrations. Methods: Indoor radon concentrations in a total of 30 places were measured from January 18 to 21, 2016, targeting six buildings in Seoul with different completion years. The measurement was conducted according to the radon measurement guidelines for indoor air suggested by the Ministry of Environment. Results: As a result of comparing each average concentration, underground area concentration was $42.850{\pm}22.501Bq/m^3$, and that of the ground floors was $27.850{\pm}12.232Bq/m^3$, which was lower than the concentration in the underground areas and statistically significant (p=0.045). As a result of comparing the concentration according to whether or not outside air entered, the average concentration for ventilated areas was $24.876{\pm}11.833Bq/m^3$, and the average concentration for enclosed areas was $47.892{\pm}19.375Bq/m^3$. The concentration in ventilated areas was lower at a statistically significant level (p=0.001). Finally, as a result of the multiple regression analysis for evaluating the factors influencing radon concentration, only ventilation was significant (p=0.007). Conclusions: As a result of measuring radon in office buildings, there was no place that exceeding the recommended standard of the US EPA, but the concentration in poorly ventilated areas was measured to be high. An effort to manage radon concentration and reduce it through the improvement of ventilation systems, repeated measurement is necessary in the future.

Bacterial Contamination and Disinfection Status of Laryngoscopes Stored in Emergency Crash Carts

  • Choi, Jae Hyung;Cho, Young Soon;Lee, Jung Won;Shin, Hee Bong;Lee, In Kyung
    • Journal of Preventive Medicine and Public Health
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    • v.50 no.3
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    • pp.158-164
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    • 2017
  • Objectives: To identify bacterial contamination rates of laryngoscope blades and handles stored in emergency crash carts by hospital and area according to the frequency of intubation attempts. Methods: One hundred forty-eight handles and 71 blades deemed ready for patient use from two tertiary hospitals were sampled with sterile swabs using a standardized rolling technique. Samples were considered negative (not contaminated) if no colonies were present on the blood agar plate after an 18-hour incubation period. Samples were stratified by hospital and according to the frequency of intubation attempts (10 attempts per year) using the ${\chi}^2-test$ and Fisher exact test. Results: One or more species of bacteria were isolated from 4 (5.6%) handle tops, 20 (28.2%) handles with knurled surfaces, and 27 (18.2%) blades. No significant differences were found in microbial contamination levels on the handle tops and blades between the two hospitals and two areas according to the frequency of intubation attempts. However, significant differences were found between the two hospitals and two areas in the level of microbial contamination on the handles with knurled surfaces (p<0.05). Conclusions: Protocols and policies must be reviewed to standardize procedures to clean and disinfect laryngoscope blades and handles; handles should be re-designed to eliminate points of contact with the blade; and single-use, one-piece laryngoscopes should be introduced.

Preventive effect of a Schizandrin C derivative DDB-mixed preparation (DWP-04) against hepatotoxicity induced by Carbon Tetrachloride (사염화탄소로 유발된 간독성에 대한 오미자 Schizandrin C 유도체 DDB 복합물 DWP-04의 예방효과)

  • Lee, Jung-Hee;Chi, Sang-Cheol;Kim, Seok-Hwan;Shin, Young-Ho;Park, Hee-Juhn;Choi, Jong-Won
    • Korean Journal of Pharmacognosy
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    • v.36 no.1 s.140
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    • pp.44-49
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    • 2005
  • The protective effects of the DWP-04 [DDB : selenium yeast: glutathione {31.1 : 6.8 : 62.1 (%, w/w)} against hepatotoxicity by carbon tetrachloride $(CCl_4)$ were studied in rats. The rats were intraperitoneally injected with $CCl_4$ (50% in com oil) at initial dose of 1 ml/kg followed by 0.5 ml/kg 3 times during 1 week. The DWP-04 (50, 100 or 200 mg/kg) or its vehicle was administered everyday before the start of $CCl_4$ injection for two weeks. $CCl_4$ induced hepatocelluar degeneration and necrosis, which led to a great increase in serum aminotransferase, alkaline phosphatase activity and serum lipid levels. It was found by biochemical analysis that $CCl_4$ treatment remarkably increased thiobarbituric acid reactive substances and physphatidylcholine hydroperoxide in hepatic tissues and induced antioxidant enzymes such as catalase and superoxide dismutase (SOD). Liver and serum lipids were significantly lower in rats fed on DWP-04 than in rats induced by $CCl_4$ only-treatment. These results suggested that the DWP-04 could be a promising candidate for the protection of liver injury based on the preventive effects against lipid peroxidation and serum biochemical parameters.

Evaluation of a Schzandrin C Derivative DDB-mixed Preparation(DWP-04) on Acetaminophen Detoxification Enzyme System in the Animal Model (오미자 Schizandrin C 유도체 DDB 복합물 DWP-04가 Acetaminophen 해독계에 미치는 영향)

  • Park, Hee-Juhn;Lee, Myeong-Seon;Chi, Sang-Cheol;Lee, Kyung-Tae;Shin, Young-Ho;Choi, Jong-Won
    • Korean Journal of Pharmacognosy
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    • v.36 no.2 s.141
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    • pp.81-87
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    • 2005
  • The effects of the DWP-04 [DDB:selenium yeast:glutathione (31.1 : 6.8 : 62.1 (w/w%)] on acetaminophen detoxification enzyme system were studied in rats. Treatment with DWP-04 was prevented againt acetaminophen-induiced hepatotoxicity in rat as evidenced by the decreased formation of lipid peroxide. Effect of DWP-04 on the activities of free radical-generating enzymes, free radical scavenging enzymes and glutathione-related enzymes as well as detoxification mechanism of DWP-04 against acetaminophen-treated was investigated in rat. Activities of cytochrome p450, cytochrome b5, aminopyrine demethylase and aniline hydroxylase as free radical-generating enzymes activities were decreased by the treatment with DWP-04 against acetaminophen treated. Although acetaminophen-induced hepatotoxicity results in the significantly decrease in the level of hepatic glutathione and activities of glutathine S-transferase, quinone reductase, glutathione reductase and ${\gamma}-glutamyl-$cysteine synthetase, these decreasing effects were markedly lowered in the DWP-04-treated rat. Therefore, it was concluded that the mechanism for the observed preventive effect of DWP-04 against the acetaminophen-induced hepatotoxicity was associated with the decreased activities in the free radical-generating enzyme system.

Factors Affecting the Efficiency of Animal Cloning by Somatic Cell Nuclear Transfer

  • Kim, Min-Goo;Park, Chi-Hun;Lee, Sang-Goo;Seo, Hee-Won;Choi, Yo-Han;Lee, Chang-Kyu;Ka, Hak-Hyun
    • Journal of Embryo Transfer
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    • v.23 no.2
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    • pp.67-76
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    • 2008
  • Since the birth of Dolly using fully differentiated somatic cells as a nuclear donor, viable clones were generated successfully in many mammalian species. These achievements in animal cloning demonstrate developmental potential of terminally differentiated somatic cells. At the same time, the somatic cell nuclear transfer (SCNT) technique provides the opportunities to study basic and applied biosciences. However, the efficiency generating viable offsprings by SCNT remains extremely low. There are several explanations why cloned embryos cannot fully develop into viable animals and what factors affect developmental potency of reconstructed embryos by the SCNT technique. The most critical and persuasive explanation for inefficiency in SCNT cloning is incomplete genomic reprogramming, such as DNA methylation and histone modification. Numerous studies on genomic reprogramming demonstrated that incorrect DNA methylation and aberrant epigenetic reprogramming are considerably correlated with abnormal development of SCNT cloned embryos even though its mechanism is not fully understood. The SCNT technique is useful in cloning farm animals because pluripotent stem cells are not established in farm animal species. Therapeutic cloning combined with genetic manipulation will help to control various human diseases. Also, the SCNT technique provides a chance to overcome excessive demand for the organs by production of transgenic animals as xenotransplantation resources. Here, we describe the factors affecting the efficiency of generating cloned farm animals by the SCNT technique and discuss future directions of animal cloning by SCNT to improve the cloning efficiency.

Prediction of Material Behavior and Failure of Fresh Water Ice Based on Viscoplastic-Damage Model (점소성 손상모델 기반 담수빙 재료거동 및 파손 예측)

  • Choi, Hye-Yeon;Lee, Chi-Seung;Lee, Jong-Won;Ahn, Jae-Woo;Lee, Jae-Myung
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.3
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    • pp.275-280
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    • 2011
  • In the present study, a unified viscoplastic-damage model has been applied in order to describe the mechanical characteristics of fresh water ice such as nonlinear material behavior and volume fraction. The strain softening phenomenon of fresh water ice under quasi-static compressive loading has been evaluated based on unified viscoplastic model. The material degradation such as growth of slip/fraction has quite close relation with material inside damage. The volume fraction phenomenon of fresh water ice has been identified based on volume fraction (nucleation and growth of damage) model. The viscoplastic-damage model has been transformed to the fully implicit formulation and the discretized formulation has been implemented to ABAQUS user defined subroutine (User MATerial: UMAT) for the benefit of application of commercial finite element program. The proposed computational analysis method has been compared to uni-axial compression test of fresh water ice in order to validate the compatibilities, clarities and usefulness.

Analysis of Articles Published in Korean Journal of Oriental Physiology and Pathology for Recent 3 Years (최근 3년간 발표된 동의생리병리학회지 논문의 방법론 및 통계처리기법에 관한 보고)

  • Ko, Mi-Mi;Kang, Byeong-Kab;Kang, Kyung-Won;Park, Sae-Wook;Kim, Bo-Young;Kim, Jung-Chul;Choi, Sun-Mi
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.1
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    • pp.189-193
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    • 2008
  • We analyzed the research type and statistical methods in Korean Journal of Oriental Physiology and Pathology for describing the trends of Oriental medicine research. The data for the analysis of trends in Oriental medicine research was taken from a total 808 articles published in Korean Journal of Oriental Physiology and Pathology from 2004 to 2006. We surveyed the number of authors, the institutes involved in each study, and used languages in each study. Also we seperated by epidemiological study design, the studies into categories and statistical methods into 13 categories. Results showed that descriptive statistics was used in 125(14.4%) papers. Also t-test, analysis of variance, multiple comparison, chi-square test, and non-parametric test were used in 338(38.9%), 147(16.9%), 81(9.3%), 27(3.1%), 23(2.6%) papers, respectively. And 62(7.1%) papers of the involved papers didn't use statistical methods. To improve the quality of Oriental medicine related articles, we have to use proper statistical methods with consultation of statistician or other experts before accepting a manuscript are needed.

Benthic Foraminiferal Communities of Surface Sediments in the Southwestern Continental Shelf of the East Sea, Korea (동해 남서대륙붕 표층퇴적물의 살아있는 저서성 유공충 분포)

  • Woo, Han-Jun;Oh, Jae-Kyung;Kim, Hyo-Young;Choi, Dong-Lim;Lee, Chi-Won
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.2 no.1
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    • pp.14-20
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    • 1997
  • The southwestern continental shelf of the East Sea, Korea developed mud deposits as a belt in the inner shelf area from Pusan to Pohang. The general surface sediments consist of very poorly to poorly sorted muddy sediment. The differences of physical, geological and geomorphic conditions in the study area may control and produce distinctive foraminiferal populations. To establish a baseline of environment for the muddy sediments in the southwestern continental shelf of the East Sea, 17 stations were sampled and proved to contain 45 species of living benthic foraminifera. Analysis of the foraminiferal populations in cluster analysis recognized to five habitat zones. These habitat zones contain distinctive cooccurrences of the entire occurring species. Foraminiferal community composition appeared to be closely interrelated of water masses, depths, nutrients and sediment characters.

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