TTAC-0001, a human monoclonal antibody targeting VEGFR-2/KDR, blocks tumor angiogenesis

Lee, Weon Sup,Pyun, Bo-Jeong,Kim, Sung-Woo,Shim, Sang Ryeol,Nam, Ju Ryoung,Yoo, Ji Young,Jin, Younggeon,Jin, Juyoun,Kwon, Young-Guen,Yun, Chae-Ok,Nam, Do-Hyun,Oh, Keunhee,Lee, Dong-Sup,Lee, Sang Hoon Taylor Francis 2015 mAbs Vol.7 No.5

Asiatic acid derivatives protect primary cultures of rat hepatocytes against carbon tetrachloride-induced injury via the cellular antioxidant system.

Lee, Mi Kyeong,Kim, Seung Hyun,Yang, Hyekyung,Lim, Doo-Yeon,Ryu, Je-Ho,Lee, Eung Seok,Jew, Sang-Sup,Park, Hyeung-Guen,Sung, Sang Hyun,Kim, Young Choong Natural Product Communications 2009 Natural product communications Vol.4 No.6

<P>We attempted to elucidate the hepatoprotective mechanism of two asiatic acid (AS) derivatives, 3beta,23-dihydroxyurs-2-oxo-12-ene-28-oic acid (AS-10) and 3beta,23-dihydroxyurs-12-ene-28-oic acid (AS-14), which exhibited significant protective activity against carbon tetrachloride (CCl4)-induced hepatotoxicity in primary cultures of rat hepatocytes. Our findings showed that AS-10 and AS-14 preserved the level of glutathione and the activities of antioxidant enzymes such as glutathione reductase, glutathione peroxidase, superoxide dismutase and catalase. In addition, these compounds ameliorated lipid peroxidation, as demonstrated by a reduction in the production of malondialdehyde. Furthermore, AS-10 and AS-14 did not restore the reduced total GSH level by BSO, indicating that the hepatoprotective activities of these compounds may be involved, in part, by regulating GSH synthesis. From these results, we suggest that both AS-10 and AS-14 exerted their hepatoprotective activities against CCl4-induced injury by preserving the cellular antioxidative defense system.</P>

An Under-Frequency Load Shedding Scheme Design for a Large Steelworks with Self-Generation System

Sang-Seok Lee,Ji-Ho Park,Ki-Seok Jeong,Heung-Guen Kim 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.5

This paper presents a load-shedding scheme for a large steelworks with several self-generation units. The power system of the steelworks can be separated from a utility grid in case of disturbances. Also, some substations with generators in the steelworks can be isolated due to the tie line tripping. These situations cause an under-frequency events as the result of the imbalance between generation and load. A system stabilizing controller (SSC) system is the core of the proposed load shedding scheme for the frequency stabilization. The SSC system performs a pre-calculation for load-shedding (LS) quantity before an event and a post-calculation to provide against a deficient load-shedding in the pre-calculated load-shedding. The back-up protection system is used to counteract situations in which the SSC system does not operate normally. Also, the load-shedding by frequency calculation is carried out for subsequent disturbance such as an additional generator tripping. The hardware based proposed scheme has been applied to the steelworks. The several under-frequency events causing a load-shedding are examined through the transient stability analysis by using ETAP. The simulation results show that the proposed scheme effectively stabilizes the frequency within the continuous frequency operation range of generators.

Performance of a Coagulant-Membrane Bioreactor for the Removal of Dissolved Organic Matter and Phosphorus

Lee, Jung-Yeol,Choi, Bo-Kyung,Maeng, Sung Kyu,Ahn, Kyu-Hong,Song, Kyung-Guen The Society of Chemical Engineers Japan 2013 Journal of chemical engineering of Japan Vol.46 No.2

An efficient modeling technique for floor vibration in multi-story buildings

Lee, Dong-Guen,Ahn, Sang-Kyoung,Kim, Jinkoo Techno-Press 2000 Structural Engineering and Mechanics, An Int'l Jou Vol.10 No.6

Analysis of a framed structure for vertical vibration requires a lot of computational efforts because large number of degrees of freedom are generally involved in the dynamic responses. This paper presents an efficient modeling technique for vertical vibration utilizing substructuring technique and super elements. To simplify the modeling procedure each floor in a structure is modeled as a substructure. Only the vertical translational degrees of freedom are selected as master degrees of freedom in the inside of each substructure. At the substructure-column interface, horizontal and rotational degrees of freedom are also included considering the compatibility condition of slabs and columns. For further simplification, the repeated parts in a substructure are modeled as super elements, which reduces computation time required for the construction of system matrices in a substructure. Finally, the Guyan reduction technique is applied to enhance the efficiency of dynamic analysis. In numerical examples, the efficiency and accuracy of the proposed method are demonstrated by comparing the response time histories and the analysis time.

Detected Range of the Deicer around the Highway

Sung Hyeon Cho,Goon Taek Lee,Byeong Duk Lee,Jin Hwan Kim,Do Soon Kim,So Young Moon,Dong Guen Lee,Jeong Min Choi,Jun Young Kim 한국도로학회 2018 한국도로학회 학술대회 발표논문 초록집 Vol.2018 No.05

The composition of the deicer sprayed on the highway is spreading over the highway by the scattering or snow removal activity, or car movement and consequently affecting the vegetation environment around the highway. These are the cause of the damage of fruit trees and crops, and also the cause of corrosion of highway structures. The goal of this study is to estimate the detected range of deicer components from a highway. The concentration of the deicer components in gauze and soil were investigated according to the crossing distance from the highway. The data collected were then used to estimate the concentration range of deicer components in a rage of distance up to 100 m from the highway where the deicer was spread. The sample time and weight of gauze were measured before and after installation, and the soil was collected at more than three points in parallel with the highway at the gauze installation point. The components in gauze and soil were investigated in addition to the deicer components (Ca2+, Na+, Cl-) as well as Mg2+ and K+. As Ca2+ and Cl- components of deicer were affected by agricultural use, Na+ component was selected as a tracer and further SAR (Sodium Adsorption Ratio) of soil was analyzed to examine the degree of influence on vegetation indirectly. The gauze concentration was evaluated by the concentration of the deicer ingredient at the background concentration of the blank gauze. The total amount of the deicer sprayed in the study road for 4 months (winter season) was about 93 ton/km. In the gauze test, the spread of the deicer was detected at a distance of 100 m in study area, but the concentration of the deicer in the gauze by distance decreased rapidly within 10 m from the highway. And concentration of the deicer components in gauze and soil came down after rainy season (August ~ Sep.). The results showed that the components of the deicer could be spread widely by the wind. The effective range of the deicer on vegetation based on SAR in soil was estimated to be less than 20 m from the highway. This study examines the concentration changes of the deicer components in gauze and soils and shows that deicer components sprayed on the highway are accumulated and moved over time by wind, snow removal, terrain, water system and land use around the highway.

An Under-Frequency Load Shedding Scheme Design for a Large Steelworks with Self-Generation System

Lee, Sang-Seok,Park, Ji-Ho,Jeong, Ki-Seok,Kim, Heung-Guen The Korean Institute of Electrical Engineers 2016 Journal of Electrical Engineering & Technology Vol.11 No.5

<P>This paper presents a load-shedding scheme for a large steelworks with several self generation units. The power system of the steelworks can be separated from a utility grid in case of disturbances. Also, some substations with generators in the steelworks can be isolated due to the tie line tripping. These situations cause an under-frequency events as the result of the imbalance between generation and load. A system stabilizing controller (SSC) system is the core of the proposed load shedding scheme for the frequency stabilization. The SSC system performs a pre-calculation for load shedding (LS) quantity before an event and a post-calculation to provide against a deficient load shedding in the pre-calculated load-shedding. The back-up protection system is used to counteract situations in which the SSC system does not operate normally. Also, the load-shedding by frequency calculation is carried out for subsequent disturbance such as an additional generator tripping. The hardware based proposed scheme has been applied to the steelworks. The several under-frequency events causing a load-shedding are examined through the transient stability analysis by using ETAP. The simulation results show that the proposed scheme effectively stabilizes the frequency within the continuous frequency operation range of generators.</P>

Expression of Epstein-Barr Virus Gene and Clonality of Infiltrated T Lymphocytes in Epstein-Barr Virus-associated Gastric Carcinoma

Lee, Jae-Myun,Kim, Ho-Guen,Noh, Sung-Hoon,Lee, Won-Young,Kim, Se-Jong,Park, Jeon-Han The Korean Association of Immunobiologists 2011 Immune Network Vol.11 No.1

Background: Epstein-Barr virus associated gastric lymphoepithelioma-like carcinoma (LELC) is characterized by the intensive infiltration of lymphoid cells, the presence of EBV, and the better prognosis over typical adenocarcinoma. Thus, it was assumable that viral latent proteins may be responsible for the recruitment of a certain T cell repertoire to EBV-associated gastric carcinoma. Methods: To examine above possibility, EBV gene expression in gastric carcinoma tissues and usage of TCR among the tumor infiltrating lymphocytes were analyzed. Results: EBV specific DNA and EBERs RNA were detected in 4 out of 30 patients. RT-PCR analysis revealed that all 4 of EBV-positive tumor tissues expressed EBNA1 mRNA and BARTs and LMP2a was detected only one sample out of 4. However, the EBNA2 and LMP-1 transcripts were not detected in these tissues. $CD8^+$ T cells were the predominant population of infiltrating lymphocytes in the EBV-positive gastric carcinoma. According to spectra type analysis of infiltrating T cells, 10 predominant bands were detected by TCR $V{\beta}$ CDR3 specific RT-PCR from 4 EBV-positive tumor tissues. Sequence analysis of these bands revealed oligoclonal expansion of T cells. Conclusion: These findings suggest that clonally expanded T cells in vivo might be a population of cytotoxic T cells reactive to EBV-associated gastric carcinoma.

Analysis of a Building Structure with Added Viscoelastic Dampers

Lee Dong Guen,Hong Sung Il,Kim Jin Koo 한국지진공학회 1998 한국지진공학회논문집 Vol.2 No.3

Steel structures with added viscoelastic dampers are analysed to investigat their behavior under earthquake excitation. The direct integration method, which produces exact solution for the non-proportional or non-classical damping system, is used throughout the analysis. The results from modal strain energy method are also provided for comparison. Then a new analytical a, pp.oach, based on the rigid floor diaphragm assumption and matrix condensation technique, is introduced, and the results are compared with those obtained from direct integration method and modal strain energy method. The well known phenomenon, that the effectiveness of the viscoelastic dampers depends greatly on the location of the dampers, is once again confirmed in the analysis. It is also found that the modal strain energy method generaly underestimates the responses obtained from the direct integration method, especially when the dampers are placed in only a part of the building. The proposed method turns out to be very efficient with considerable saving in computation this and reasonably accurate considering the reduced degrees of freedom.

The Secondary Products by Ozone-initiated Reaction with Terpenes Emitted from Natural Paint : 천연 페인트로부터 방출되는 털핀류와 오존 반응에 의한 이차 오염물질 생성

Sang-Guen Jung(정상근),Rheo B. Lamorena, Woo Jin Lee(이우진),Gwi-Nam Bae(배귀남),Kil-Choo Moon(문길주),Shin-Do Kim(김신도) 한국실내환경학회 2004 한국실내환경학회지 Vol.1 No.1

입자, 알데히드류, 케톤 같은 유해한 휘발성 유기화합물들이 생성된다는 보고가 있었다. 이번 연구에서는 천연 페인트에서 방출되는 털핀과 오존의 반응에 의한 미세 입자와 이차 유기화합물 생성에 대해서 조사하였다. 시편에 페인트를 칠하여 실내에서 건조시킨 후 테플론 챔버 내에서 오존과 반응시켰다. α, β-파이닌은 GC-MS와 FTIR을 사용하여 정성하였다. 입자생성에 대한 오존의 영향을 조사하기 위해 여러가지 실험이 수행되었다. 오존 농도가 100ppb에서 1000ppb로 증가할 때 입자 수농도는 8,000에서 70,000 particles/㎤까지 증가하였다. 포름알데하이드, 아세트알데하이드, 아세톤+아크로레인, 프로피온알데하이드 등의 반응 생성물은 HPLC로 분석하였다. 이런 화합물들은 잠재적으로 유해한 화합물이고, 인체에 해로운 영향을 끼친다. 이번 연구결과는 친환경제품의 실내공기질에 대한 해로운 영향에 대한 보기를 보여주었다. The use of natural paint for the application to walls and furnishings is now increasing to improve indoor air quality, thereby the natural paint could be a significant source of biogenic volatile organic compounds (BVOCs) in indoor environments. Recent studies have shown that gas-phase reactions between terpenes and ozone can generate sub-micron size particles and toxic volatile organic compounds such as aldehydes and ketones. In this research, we have studied the formation of particles and secondary organic compounds during the reaction of ozone with terpenes emitted from commercial natural paint. The paint applied onto stainless steel was dried and oxidized in a teflon chamber. Two monoterpenes (α- and β-pinenes) were identified by FTIR and GC/MS. Several tests were performed to evaluate the effects of ozone concentration on particle formation. Increased ozone levels significantly affect the increase of particle number concentration (monitored with SMPS), which results in the increase of particle counts ranging from 8,000 to 70,000 particles/㎤. Gas-phase products such as formaldehyde, acetaldehyde, acetone + acrolein, and propionaldehyde were identified during the terpene/ozone reactions by HPLC. These compounds are potential hazardous chemical compounds having harmful health effects to animals and plants. The results obtained from this study provide an insight on the adverse effect of eco-friendly natural product on indoor air quality (IAQ).