Hepatoprotective Effect of a Preparation of Combined Glutathione- Enriched Yeast and Rice Embryo/Soybean Extracts

Dongsun Park,Heon-Sik Lee,Tae Myoung Kim,Jugyeong Song,Jeong Hee Jeon,Sunhee Shin,Seong Soo Joo,Hyoung Kook Park,Won Kyung Lee,Jin Tae Hong,Yun-Bae Kim 한국실험동물학회 2009 Laboratory Animal Research Vol.25 No.1

The effects of GEY+RES, a preparation of combined glutathione-enriched yeast (GEY) and rice embryo/soybean (RES) extracts (20:1), on carbon tetrachloride (CCl₄)-induced hepatic injury were investigated in male Sprague-Dawley rats. The rats were orally administered with GEY+RES at low (GEY+RES=50+2.5 ㎎/㎏), medium (100+5 ㎎/㎏) or high (200+10 mg/kg) doses for 2 weeks, followed by intraperitoneal challenge with CCl₄ (1 mL/㎏) 30 min after the final treatment. Twenty four hours later, initial biliary excretion and time-course of blood concentration of intravenously-injected bromosulphalein were examined. In addition, blood parameters of hepatic injury in accordance with histopathological findings were analyzed. The biliary excretion time and clearance of bromosulphalein were greatly delayed by CCl₄ injection, which were recovered by GEY+RES in a dose-dependent manner, resulting in decreases to a half level by medium and high doses. CCl₄ drastically increased the blood markers of hepatotoxicity, and caused centrilobular congestion, hepatocytic degeneration, lipid droplets and inflammatory cell infiltration, leading to disintegration of hepatic cords. The increased biochemical parameters and hepatic lesions induced by CCl₄ were significantly attenuated by GEY+RES treatment. The results suggest that GEY+RES might prevent liver dysfunction induced by CCl₄, and that GEY+RES could be a potential candidate for the prevention of hepatic disorders.

Antioxidative and Antidiarrheal Effects of Persimmon Extracts

Dongsun Park,Sun Hee Lee,Dae-Kwon Bae,Young Jin Choi,Tea Kyun Kim,Yun-Hui Yang,Goeun Yang,Sang-Chul Kwon,Do Ik Lee,Sung Soo Joo,Yun-Bae Kim 한국실험동물학회 2010 Laboratory Animal Research Vol.26 No.4

Since oxidative stresses are involved in gastroenteritis and diarrhea, we investigated antioxidative and antidiarrheal activities of persimmon flesh extract (PFE) and persimmon calyx extract (PCE) in vitro and in vivo, respectively. PCE significantly scavenged 1,1-diphenyl-2-picrylhydrazyl hydrate and 2,2'-azinobis (3-ethylbenzthiazoline-6-sulfonic acid) from 500 ㎍/mL, although PFE was ineffective. In addition, PFE and PCE exhibited strong nitric oxide-scavenging effects from 1 μg/mL, in which PCE was superior to ascorbic acid (50 μM). Furthermore, PFE and PCE significantly inhibited FeCl3-induced lipid peroxidation as well as Cu<SUP>2+</SUP>/H₂O₂-induced protein oxidation from 10 μg/mL. In vivo charcoal-propulsion assay, in contrast to a negligible effect of PFE, treatment with PCE (160-500 ㎎/㎏) markedly inhibited intestinal motility. The results indicate that extracts of persimmon, especially PCE, possess antioxidative, antiinflammatory and antidiarrheal activities. Therefore, it is suggested that persimmon extracts could be used for the relief of gastroenteritis and diarrhea.

Static and dynamic mechanics analysis on artificial hip joints

DONGSUN LEE,Fethma,Joong Yeon Yim,Junseok Kim 한국산업응용수학회 2009 한국산업응용수학회 학술대회 논문집 Vol.4 No.2

The purpose of this paper is to present the optimization of appearance and displacement of the prostheses. Artificial hip joints would reduce pains as well as restore walking motion. But dislocation and wearness of this are considered as serious side effects of the surgical replacement beyond the prostheses’ excellent performance. New design based on mathematical model for an artificial hip joint will elongate lifetime and provide much more natural movement by engaging forces. And to manipulate model parameters such as the radius of femoral and acetabular cup and structural support, we take advantage of ABAQUS 6.8-1 which is a finite element solver used for stress strain and types of in mechanical and structural analysis. The finite element method was employed in this paper to compare.

NUMERICAL ANALYSIS OF CELL GROWTH IN SCAFFOLDS

Dongsun Lee,Darea Jeong,Hyun Geun Lee,Junseok Kim 한국산업응용수학회 2009 한국산업응용수학회 학술대회 논문집 Vol.2009 No.5

A mathematical model to predict the growth of cells is a powerful tool in scaffold designing. The improved understanding derived from this mathematical model and its numerical analysis are useful in the design of three-dimensional scaffolds that can support more confirm growth of cells.

Silk and silkworm pupa peptides suppress adipogenesis in preadipocytes and fat accumulation in rats fed a high-fat diet.

Lee, Sun Hee,Park, Dongsun,Yang, Goeun,Bae, Dae-Kwon,Yang, Yun-Hui,Kim, Tae Kyun,Kim, Dajeong,Kyung, Jangbeen,Yeon, Sungho,Koo, Kyo Chul,Lee, Jeong-Yong,Hwang, Seock-Yeon,Joo, Seong Soo,Kim, Yun-Bae Steinkopff 2012 EUROPEAN JOURNAL OF NUTRITION Vol.51 No.8

<P>The objective was to confirm the anti-obesity activity of a silk peptide (SP) and a silkworm pupa peptide (SPP) in rats fed a high-fat diet (HFD) and to elucidate their action mechanism(s) in a preadipocyte culture system. In an in vitro mechanistic study, the differentiation and maturation of 3T3-L1 preadipocytes were stimulated with insulin (5 mu g/mL), and effects of SP and SPP on the adipogenesis of mature adipocytes were assessed. In an in vivo anti-obesity study, male C57BL/6 mice were fed an HFD containing SP or SPP (0.3, 1.0, or 3.0%) for 8 weeks, and blood and tissue parameters of obesity were analyzed. Hormonal stimulation of preadipocytes led to a 50-70% increase in adipogenesis. Polymerase chain reaction and Western blot analyses revealed increases in adipogenesis-specific genes (leptin and Acrp30) and proteins (peroxisome proliferator-activated receptor-gamma and Acrp30). The hormone-induced adipogenesis and activated gene expression was substantially inhibited by treatment with SP and SPP (1-50 mu g/mL). The HFD markedly increased body weight gain by increasing the weight of epididymal and mesenteric fat. Body and fat weights were significantly reduced by SP and SPP, in which decreases in the area of abdominal adipose tissue and the size of epididymal adipocytes were confirmed by magnetic resonance imaging and microscopic examination, respectively. Long-term HFD caused hepatic lipid accumulation and increased blood triglycerides and cholesterol, in addition to their regulatory factors Acrp30 and leptin. However, SP and SPP recovered the concentrations of Acrp30 and leptin, and attenuated steatosis. SP and SPP inhibit the differentiation of preadipocytes and adipogenesis by modulating signal transduction pathways and improve HFD-induced obesity by reducing lipid accumulation and the size of adipocytes.</P>

The fractional Allen–Cahn equation with the sextic potential

Lee, Seunggyu,Lee, Dongsun Elsevier 2019 Applied mathematics and computation Vol.351 No.-

<P><B>Abstract</B></P> <P>We extend the classical Allen–Cahn (AC) equation to the fractional Allen–Cahn equation (FAC) with triple-well potential. By replacing the spatial Laplacian and double-well potential with fractional Laplacian and triple-well potential, we observe different dynamics. This study leads us to understand different properties of the FAC equation. We seek the existence, boundedness, and unique solvability of numerical solutions for the FAC equation with triple-well potential. In addition, the inclusion principle for the Allen–Cahn equation is considered. These different properties make us enhance the applicability of the phase-field method to the mathematical modeling in materials science. In computation, the spectral decomposition for the fractional operator allows us to develop a numerical method for the fractional Laplacian problem. For the periodic and discrete Laplacian matrix and vector multiplication, circulant submatices are formed in more than two-dimensional case. Even if the fast Fourier transform (FFT) can be utilized in this modeling, we construct the inverse of the doubly-block-circulant matrix for the solution of the fractional Allen–Cahn equation. In doing so, it helps to straightforwardly understand the numerical treatment, and exploit the properties of the discrete Fourier transforms.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Boundedness of numerical solutions for the fractional Allen – Cahn equation with sextic polynomial is under consideration. </LI> <LI> From the numerical aspect, the inclusion principle is proven to hold only for the Allen – Cahn equation. </LI> <LI> Effects of the fractional order and parameters of the equation is analyzed. </LI> <LI> Eigenvectors of the discrete Laplacian are used for investigating the behaviors of the fractional Allen – Cahn equation. </LI> <LI> The numerical study of the fractional Allen – Cahn equation with the sextic polynomial is verified by various simulations. </LI> </UL> </P>

쇼트피닝에 의한 자동차용 베벨기어의 피로설계

이동선(Dongsun Lee),정성균(Seongkyun Cheong) 한국자동차공학회 2008 한국 자동차공학회논문집 Vol.16 No.4

저가형 IMU와 GPS수신기를 이용한 자세결정 시스템

이동선(DongSun Lee),채정근(JeongGeun Chae),이민준(Min-joon Lee),박찬식(Chansik Park) 대한전기학회 2014 대한전기학회 학술대회 논문집 Vol.2014 No.7

Diagnostic Accuracy of Working Memory Tasks Depending on Scoring Unit and Condition in Preschool Children

임동선(Dongsun Yim),김신영(Shinyoung Kim),유지원(Jeewon Yoo),이윤정(Yunjung Lee),이상언(Sangeon Lee),정하은(Haeun Chung) 한국언어청각임상학회 2017 Communication Sciences and Disorders Vol.22 No.3

배경 및 목적: 비단어따라말하기, 문장따라말하기, 매트릭스는 언어능력의 기저요인으로 주목 받아온 작업기억의 각 하위체계를 평가하기 위한 과제로, 많은 선행연구들과 임상에서 사용되어 왔다. 그러나 각 과제의 채점단위 또는 수행조건이 일치되지 않아왔던 바, 본 연구에서는 각 과제별로 언어장애를 보다 정확하고 효과적으로 판별할 수 있는 방식을 재검토하고 정확한 시행방법을 제시하고자 한다. 방법: 본 연구는 5-6세의 어휘발달지체 아동(N=40)과 일반 아동(N=40)을 대상으로 비단어따라말하기 및 문장따라말하기의 채점단위 및 매트릭스 과제의 수행조건에 따른 진단정확도를 민감도, 특이도, 양성우도비 및 음성우도비를 통하여 분석하였다. 결과: 판별분석 결과, 비단어따라말하기 과제는 음절 단위 채점방식에 비해 낱말 단위 채점방식이, 문장따라말하기 과제는 어절 단위 채점방식에 비해 문장 단위 채점방식의 진단정확도가 더욱 높은 것으로 나타났다. 매트릭스 과제는 집단 간 수행력 차이와 판별분석 결과가 순행 및 역행 조건 모두에서 유의하지 않았다. 논의 및 결론: 비단어따라말하기 과제 및 문장따라말하기 과제는 시간적 효율성이 높은 채점 방식이 진단정확도도 높은 것으로 나타나 그 임상적 효용성을 입증하였다. Objectives: The purpose of the current study was to examine the diagnostic accuracy of working memory (WM) tasks, including nonword repetition (NWR), sentence repetition (SR), and matrix tasks, as clinically efficient diagnostic tools depending on the scoring systems and task condition. Methods: Forty children with vocabulary delay (VD group) and 40 typically developing children (TD group) were administered a series of WM tasks (NWR, SR, and matrix tasks). Different scoring units were applied to each task (syllable vs. word for NWR task and word vs. sentence for SR task) while different conditions (forward matrix vs. backward matrix) were used for the matrix task. Separate discriminant function analyses were conducted with the scores calculated by the different scoring units or the different condition of the tasks as predictors. Results: Multiple discriminant function analyses for the NWR task yielded word units with higher overall classification values than syllable units, whereas for the SR task sentence units had a higher overall classification value than word units. For the matrix task, none of the conditions reached the level of significance in the discriminant function analyses. Conclusion: The results in this study support the diagnostic accuracy of the NWR task with word units and the SR task with sentence units in discriminating among the VD group and the TD group. However, caution should be used when regarding these matrix tasks as an accurate diagnostic tool, especially in young children.

GPS와 기압계를 이용한 상하동요 측정 시스템 설계

이동선(DongSun Lee),박준기(JunGi Park),강인숙(In-Suk Kang),박찬식(Chansik Park) 한국통신학회 2015 한국통신학회 학술대회논문집 Vol.2015 No.1