Induction of heme oxygenase-1 protects against podocyte apoptosis under diabetic conditions

Lee, Sang Choel,Han, Seung Hyeok,Li, Jin Ji,Lee, Sun Ha,Jung, Dong-Sub,Kwak, Seung-Jae,Kim, Seung Hye,Kim, Dong Ki,Yoo, Tae-Hyun,Kim, Jin Hyun,Chang, Se-Ho,Han, Dae Suk,Kang, Shin-Wook International Society of Nephrology 2009 Kidney international Vol.76 No.8

Heme oxygenase-1 (HO-1) is an anti-oxidant enzyme normally upregulated in response to oxidant injury. Here we determined the role of HO-1 in podocyte apoptosis in glomeruli of streptozotocin-treated rats and in immortalized mouse podocytes cultured in media containing normal or high glucose. HO-1 expression, its activity, the ratio of Bax/Bcl-2 protein, and active caspase-3 fragments were all significantly higher in isolated glomeruli of diabetic rats and in high glucose–treated podocytes. These increases were inhibited by zinc protoporphyrin treatment of the rats or by HO-1 siRNA treatment of the podocytes in culture. The number of apoptotic cells was also significantly increased in the glomeruli of diabetic rats and in high glucose–treated podocytes. Inhibition of HO-1 accentuated the increase in apoptotic cells both in vivo and in vitro. Our findings suggest that HO-1 expression protects against podocyte apoptosis under diabetic conditions.

컴포넌트기반 소프트웨어 개발 도구에 관한 연구

곽상호 順天靑巖大學 2000 論文集-順天靑巖大學 Vol.24 No.-

In most organizations the task of component recovery will be an on-going affair. Initially, large parts of an existing application may be considered to be one component, with a single, complex interface. This is the way in which most component wrapping techniques are intended to be used today. However, even taking this potentially provides greater external access to the functionality that application provides. Gradually, as the component is understood in more detail, it may be decomposed into several smaller components, increasing the reusability of each piece. As component-based development approaches mature the task of creating components from existing legacy applications is likely to be a prime target for increasing automated tool support. Here is an excellent source of information on techniques and tools for performing program understanding, and re-engineering of applications. Moving to CBSD will require signification changes in the way an organization builds software. As a result, significant financial, cultural, and emotional barriers will need to be overcome to introduce the techniques in an effective way. It is useful to consider the steps which must be taken to move to CBSD in a systematic way.

Azoloquinoxaline類의 간편한 合成에 관한 硏究 : 第1報

郭美玉,南順花,金恩慶,金眞姬,韓盛旭,李萬佶,朴義煥,金浩植 고신대학교 자연과학연구소 1993 고신대학교 자연과학연구소 논문집 Vol.3 No.-

The reaction of 2, 6-dichoroquinoxaline with m-chloroperbenzoic acid gave 2, 6-dichloroquinoxaline 4-oxide, whose reaction with sodium azide provided 7-chlorotetrazolo[1, 5-a]quinoxaline 5-oxide and not the isomeric azide. The structures of the synthesized compounds were confirmed on the basis of IR, ¹H-NMR, elemental analysis and mass spectral data.

관상 동맥 질환에서 아포 E 지단백 유전자 다형성과 혈청 지질치와의 관계

곽선영,김성구,정호석,이유경,이광희,김철현,최태명,현민수,권영주 순천향의학연구소;Soonchunhyang Medical Research Institute 2000 Journal of Soonchunhyang Medical Science Vol.6 No.1

Background and aims: The Apolipoprotein E is a ligand of both the protein component LDL receptor as well as the apo E LDL-Receptor related protein (LRP). It modulates the receptor binding of lipoproteins, with the apolipoprotein E found on cell surfaces as its component, thus serving an important role in the lipid metabolism by carrying out the intracellular transport of cholesterol in lipoproteins. The gene for apolipoprotein E is the product of three common genotypes as well as many more rare alleles. The common genotypes are ε2, ε3, and ε4, and are expressed in the three phenotype isoforms of E2, E3, and E4. In the event that E4 is the main component, a rise in the cholesterol level, as the result of down-regulation of the LDL receptor, is observed. Therefore, those samples with E4 genotypes are known to be in much higher risk of coronary artery disease than those with ε3/ε3, while those with ε2 are in low risk (with the exception of hypertiglyceremai Ⅲ). The aim of this study is to analyze in patients with ischemic heart disease the role of aplipoprotein E alleles in order to seek its correlation with coronary artery disease, as well as to seek whether the polymorphism of apo E produces any differences in the severity of coronary artery disease according to plasma lipid levels. Methods: The subjects for study were 273 patients admitted to the Internal Cardiology Division of the Soonchunhyang University Hospital form December 1998 to February 1999. The subjects were divided into the two groups of which one was ischemic heart disease (IHD) experiment group totaling 105 (avg.60.1 years of age, male/female ratio = 69/36) and the control group totaling 168 (avg. 59.7 years of age, male/female = 73:95). The coronary angiogram was given to 127 subjects, and of this total, 94 have developed significant stenosis in the coronary artery. The stages of the analyzing of the apo E phenotype was first, the separation of DNA from the blood samples, subjecting it to the PCR from with 228 base pairs of expanded products were obtained. The band was determined by means of the reverse hybridization principle on the nitrocellulose strip. Results: From the 105 patients the distributions of apo E phenotypes were as follows: ε3/2(5.7%), ε4/2(1.9%), ε3/3(70%), ε4/3(20%), ε4/4(1.9%). The relative frequencies of each allele are as follow: ε2 (0.038), ε3 (0.833), ε4 (0.128). The results show as follows: ⅰ) The IHD experiment group to have a higher occurrence of ε4/3 phenotypes as well as ε4 alleles than the control group. ⅱ) Both the control group and IHD group showed the largest distribution of ε3/3 for phenotypes, and ε4 for alleles. ⅲ) The IHD group showed less ε2/3 phenotypes as well as significantly less allele frequency of ε3 in comparison to the control group. ⅳ) the IHD group showed a much lower level of HDL in comparison to the control group, while the LDL was significantly higher; samples including the apo ε2 showed a significantly higher level of HDL than those without. Among the control group, samples including apo ε2 showed a significantly higher level of TG (triglyceride) than samples without. No significant difference was found between the experiment apo ε4 sample and the control plasma lipid sample. ⅴ) No significant correlation was found between an apo E polynorphism and the number of involved arteries of a coronary angiogram. Conclusion: Between the experiment IHD group and control group were found differences in the frequency of alleles. The polymorphism of apo E alleles may contribute as a risk factor to the development of heart disease by involving itself in the metabolism and modulation of plasma lipids.

Long/Short 훈련심볼을 이용하는 개선된 채널추정기법에 의한 IEEE 802.11a 무선 LAN 시스템의 성능 개선

곽재민,정해원,조성준,이형호 한국항행학회 2002 韓國航行學會論文誌 Vol.6 No.3

본 논문에서 IEEE 802.11a 의 규격에 따라 OFDM 무선 LAN 모뎀과 프레임 포맷을 구성하여 시뮬레이션에 의해 BER 성능을 분석하고 수정된 채널 예측 알고리즘을 적용하여 채널 예측 성능이 개선됨을 보인다. 채널 예측에 이용되는 실내 무선채널로서는 AWGN과 TDL모델을 적용한 지연확산채널을 고려한다. 우선 AWGN환경에서 규격에 제시된 전송속도 및 부호율에 따른 OFDM 무선 LAN 시스템의 성능을 분석한다. 다음으로 실내무선 채널 환경에서 채널추정이 불완전한 경우에 대해, 기존의 채널추정방식으로서 프리앰블 내의 2개의 Long 훈련 심볼을 이용하여 채널을 추정하는 경우에 대한 성능을 분석하고, 수수정된 채널 추정기법으로는 IEEE 802.11a의 프리앰블 구조를 변경하지 않으면서 Long 훈련심볼뿐만 아니라 전체 10개의 Shot 훈련심볼 중 8개의 훈련심볼들을 채널추정에 부가적으로 사용하는 방식을 채용한 경우의 성능을 분석하여 기존의 방식과 비교한다. 시뮬레이션 결과의 분석으로부터 수정된 채널 추정방식을 적용하는 경우, 규격에 정의된 프리앰블 구조의 변경없이도 잡음을 억제하는 효과를 향상시킴으로써 채널추정오차가 감소되어 채널추정성능이 개선됨을 확인하였다. In this paper, the BER performance of IEEE 802.11a OFDM WLAN system is obtained by simulation and it is shown that the proposed modified channel estimation algorithm improves the channel estimation performance of the system. The wireless channel used in channel simulation includes AWGN and delay spread channel implemented by TDL model. At first, the performance of OFDM WLAN system according to data rate and coding rate defined in standard is evaluated in AWGN channel. Then, imperfect channel estimation in indoor wireless channel is considered. After the performance of conventional channel estimation scheme using only two long training symbols is evaluated, and that of proposed modified channel estimation scheme using additional 8 short training symbol is compared with it. From the simulation results, it is shown that modified channel estimation scheme provides reduced channel estimation error and improves the channel estimation performance due to noise averaging effect with the same preamble format as defined in specification.

고속 주행 모드에서 자동차 디퓨저의 스트레이크 개수와 배치에 따른 공기저항 유동해석

이진호,박성하,최동석,한영진,곽나영,이상욱 순천향대학교 부설 산업기술연구소 2021 순천향 산업기술연구소논문집 Vol.27 No.2

This study proposes an optimized diffuser strake design that can improve driving performance for cars in high-speed driving mode. The speed of the vehicle is set to 160km/h, and the number of strake is set to 4, 6 and 8, and the angle of the diffuser is set to 4, 5 and 6 degrees. The arrangement of the strake is centered, edged and equally arranged. The optimized diffuser design induced with the Ansys Fluent analysis shows a drag coefficient of 16% less than the basic diffuser-free model at a diffuser angle of 6 degree, 8 strakes, and equal arrangement.

D-Amino Acid Aminotransferase 활성보유 고온성미생물의 탐색 및 분류학적 특성 연구

곽미선,이승구,정상철,서승현,이재흥,전영중,김영호,성문희 충남대학교 약학대학 의약품개발연구소 1999 藥學論文集 Vol.15 No.-

To acquire an industrially useful biocatalyst for the enzymatic synthesis and production of various D-amino acids, 1,300 thermophiles isolated from the soil of Korea were analyzed for D-amino acid aminotransferase (D-AAT) activity. The enzyme activity was found from 110 strains of isolated thermophiles revealing its wide occurrence in thermophiles. Enzyme activity and thermal stability of the D-AAT producers were compared. Finally we have selected four thermophiles as producers of potent biocatalysts for the D-amino acid production; two therrnophiles, Bacillus sp. LK-I and LK-2, having higher specific activity and two thermophiles, B. stearothermophilus KL-01 and Bacillus sp. KLS-0l, having higher thermal stability than the D-AAT producers. Taxonomic and physiological characteristics of the four isolated thermophiles were described herein.

종합정보통신망을 통한 제주지역 농산물 유통정보모델 구축에 관한 연구

곽호영,이상준,김장형 濟州大學校工科大學産業技術硏究所 1995 尖端技術硏究所論文集 Vol.6 No.-

In this paper, we proposed a total information system model for cheju farming industry. The purpose of the model is to provide the useful informations and services about cheju farmings. For this purpose, we analized the various types of the cheju farming system. And analized the distribution channels of the agricultural products. And surveyed the kind of agricultural informations needed for the peasants. Using the surveyed data, we designed a computer information system model which is conceptually attached on the ISDN.

채터링 제거를 위한 유도 전동기의 슬라이딩 모드 제어기 설계

郭君平,安鎬均,金星邑 창원대학교 공작기계기술연구센터 1999 연구업적집 Vol.1 No.1

본 논문에서는 유도 전동기의 슬라이딩 모드 제어기가 설계되었다. 슬라이딩 모드 제어기의 단점인 채터링 현상을 제거하기 위해 연속치 제어입력이 제안되었으며 제안된 기법으로 고속 마이크로 프로세서인 DSP를 이용한 유도전동기의 속도제어를 보였다. 슬라이딩 모드하에서의 유도 전동기는 전동기의 각속도가 지정된 궤적을 추종하도록 동작한다. 실험 결과를 통해 제안된 방법의 유용성을 보였다. This paper presents an improved sliding mode controller design for induction motor. In place of the discontinuous control inputs. continuous inputs are proposed in order to remove the undesirable chattering phenomena. which represent major drawbacks of the sliding mode controller. The design strategy is illustrated with a microprocessor based implementation for the velocity control of an induction motor. An induction motor is operated under sliding mode control such that the motor angular velocity follows a predetermined trajectory. The experimental results confirm the validity of the proposed method.

pH 5.5에서 재광화 용액의 포화도 변화가 인공 탈회된 법랑질의 재광화에 미치는 영향

곽영준,김의성,박성호,공형규,이윤,이찬영 大韓齒科保存學會 2008 Restorative Dentistry & Endodontics Vol.33 No.5

초기 법랑질 우식의 경우 주위의 pH. 유기산의 종류 및 농도,치아의 무기질 및 유기질의 화학적 조성,불소의 농도,용액의 포화도등에 의해 영향을 받는다고 하였다. 본 연구에서는 lactic acid를 이용하여 법랑질을 인공 탈회시키고, pH 5.5인 포화도가 다른 세 가지 재광화 용액 (포화도 0.25,0.30, 0.35)으로 12일간 처리한 후,편광 현미경에서 얻은 상에서 탈회 깊이의 변화,우식 표면층 폭의 변화,무기질의 양적 변화를 Photoshop, Image pro plus, Scion Image, Excel을 이용하여 비교,분석하였다. 1. pH 5.5 에서 재광화 용액의 포화도가 증가할수록 우식 표면층의 폭은 증가하였다. 2. pH 5.5 에서 l 군의 경우 우식 부위에 전반적으로 재광화가 일어났으나,3군의 경우 우식 표면층에서만 재광화의 양상이 뚜렷하게 나타났고, 2군에서는 1군과 3군의 중간적인 양상이 나타났다. 한편,3군의 경우 1, 2 군보다 우식 표면층의 폭이 유의하게 증가하였다. 결론적으로 본 실험의 조건에서 포화도가 가장 낮았던 군에서는 우식 표면층에서 우식 섬부까지 전반적으로 재광화가 일어난 반면,포화도가 높아질수록 우식 표면층의 폭은 증가하였으나 우식 심부에서는 큰 변화를 보이지 않는 양상이 나타났다. The purpose of this study is to observe and compare the remineralization tendencies of artificially demineralized enamel by remineralization solutions of different degree of saturations at pH 5.5, using a polarizing microscope and computer programs (Photoshop, Image pro plus, Scion Image, Excel). For this study, 36 sound permanent teeth with no signs of demineralization, cracks, or dental restorations were used. The specimens were immersed in lactic acid demineralization solution for 3 days in order to produce dental caries artificially that consist of surface and subsurface lesions. Each of 9 or 10 specimens was immersed in pH 5.5 lactic acid buffered remineralization solution of three different degrees of saturation (0.25, 0.30, 0.35) for 12 days. After the demineralization and remineralization, images were taken by a polarizing microscope (× 100). The results were obtained by observing images of the specimens, and using computer programs, the density of caries lesions were determined. In conclusion, in the group with the lowest degree of saturation, remineralization occurred thoroughly from the surface to the subsurface lesion, whereas in the groups with greater degree of saturation showed no significant change in the subsurface lesion, although there was corresponding increase in the remineralization width on the surface zones.