• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1132-1137
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• 2007

This paper describes a Unified Chassis Control (UCC) strategy to prevent vehicle rollover by integrating individual modular chassis control systems such as Electronic Stability Control (ESC) and Continuous Damping Control (CDC). The UCC threshold is determined from a rollover index computed by estimated roll angle, roll rate and measured lateral acceleration. A direct yaw moment control method is used to design the ESC based on a 2-D bicycle model. Similarly, the CDC is designed based on a 2-D roll model using a direct roll moment control method. The performance of the proposed UCC scheme is investigated and compared to that of modular chassis controllers through computer simulations using a validated vehicle simulator. It is shown that the proposed the UCC can lead to improvements in vehicle stability and efficient actuation of chassis control systems.

• Nuclear Engineering and Technology
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• v.4 no.4
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• pp.273-279
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• 1972

Requirements necessary for the construction of a fast critical assembly in this country are briefly reviewed. The critial masses of a spherical plutonium core with various spherical reflectors and its thicknesses are calculated using IDX, which is a computer code written for fast reactor analysis. The compilation of this code was made on CDC 3300/Master and UNIVAC 1106/EXEC 8. The calculated results are completely depicted, and compared with other results in this report. The Russian formatted 29 group cross section set generated by ETOX-2 using ENDF/B Version II file at Hanford is used in the calculations.

• Journal of Life Science
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• v.23 no.9
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• pp.1109-1117
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• 2013

Induction of G1 Arrest by Methanol Extract of Lycopus lucidus in Human Lung Adenocarcinoma A549 Cells Lycopus lucidus, a herbaceous perennial, is used as a traditional remedy in East Asia, including China and Korea. It has been reported that L. lucidus has anti-allergic effects, inhibitory effects on cholesterol acyltransferase in high glucose-induced vascular inflammation, and anti-proliferative effects in human breast cancer cells. However, the molecular mechanisms of the anti-cancer effects of L. lucidus have not yet been fully determined. In this study, we evaluated the anti-cancer effect and the mechanism of action of L. lucidus in human lung adenocarcinoma A549 cells using methanol extracts of L. lucidus (MELL). MELL treatment showed cytotoxic activity in a dose-dependent manner and induced G1 arrest in A549 cells. The induction of G1 arrest by MELL was associated with the up-regulation of phospho-CHK2 and the down-regulation of Cdc25A phosphatase. In addition, MELL treatment induced decreased expression of G1/S transition-related proteins, including CDK2, CDK4, CDK6, cyclin D1 and cyclin E. MELL also regulated the mRNA expression of CDK2 and cyclin E. On the other hand, the expression of p53 and the cyclin-dependent kinase inhibitor p21 was not induced by MELL. Collectively, these results suggest that MELL may exert an anti-cancer effect by cell cycle arrest at G1 phase through the ATM/CHK2/Cdc25A/CDK2 pathway in A549 cells.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.515-515
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• 2005

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.6
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• pp.1666-1672
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• 2005

Oriental medicinal drugs have a broad spectrum of clinical use for the cure of nervous system diseases including brain ischemic damages or neuropathies. Yet, specific drugs or drug components used in the oriental medicine in relation to none fiber regeneration are not known. In the present study, possible growth promoting effects of oriental medicinal drugs were investigated in the injured sciatic nerve system in the rat. By immunofluorescence staining, we found that Jahageo (JHG, Hominis placenta) increased Induction levels of axonal growth associated protein GAP-43 in the rat sciatic none. Small growth promoting activity was found in Golsebo (GSB, Drynariae rhizoma) and Baikhasuo (BHSO, Polygoni multiflori radix) drugs. JHG also increased cell cycle protein Cdc2 levels in the injured area of the sciatic nerves. Immunofluorescence staining indicated that induced Cdc2 protein was mostly localized in the Schwann cells in the injury area, implying that JHG activity might be related to increased Schwann cell proliferation during axonal regeneration. Moreover, levels of phospho-extracellular signal-regulated (ERK) pathway in the injured neNes were elevated by JHG treatment while levels of total ERK were unaltered. In vivo measurement of axonal regeneration using retrograde tracer showed that JHG, GSB and BHSO significantly enhanced Dil-labeled regenerating motor neurons compared with saline control. The present data suggest that oriental medicinal drugs such as JHG, GSB, and BHSO may be a useful target for developing specific drugs of axonal regeneration.

• Biomolecules & Therapeutics
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• v.31 no.3
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• pp.340-349
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• 2023

Mad2B (Mad2L2), the human homolog of the yeast Rev7 protein, is a regulatory subunit of DNA polymerase ζ that shares sequence similarity with the mitotic checkpoint protein Mad2A. Previous studies on Mad2B have concluded that it is a mitotic checkpoint protein that functions by inhibiting the anaphase-promoting complex/cyclosome (APC/C). Here, we demonstrate that Mad2B is activated in response to cisplatin-induced DNA damage. Mad2B co-localizes at nuclear foci with DNA damage markers, such as proliferating cell nuclear antigen and gamma histone H2AX (γ-H2AX), following cisplatin-induced DNA damage. However, unlike Mad2A, the binding of Mad2B to Cdc20 does not inhibit the activity of APC/C in vitro. In contrast to Mad2A, Mad2B does not localize to kinetochores or binds to Cdc20 in spindle assembly checkpoint-activated cells. Loss of the Mad2B protein leads to damaged nuclei following cisplatin-induced DNA damage. Mad2B/Rev7 depletion causes the accumulation of damaged nuclei, thereby accelerating apoptosis in human cancer cells in response to cisplatin-induced DNA damage. Therefore, our results suggest that Mad2B may be a critical modulator of DNA damage response.

• Proceedings of the Korean Statistical Society Conference
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• 2001.11a
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• pp.109-114
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• 2001

m=2 또는 n=2이고, ${\lambda}_1<{\lambda}_2$인 그룹분류가능계획을 매개디자인으로 사용한 완전이면교배가 A-최적, D-최적임을 보였다. 또한, ${\lambda}_2={\lambda}_1+1$이면 일반화된 최적계획이 됨을 보였다.

• Proceedings of the Korean Society of Toxicology Conference
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• 2006.11a
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• pp.46-54
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• 2006

The methylmercury (MeHg) is a toxic environmental pollutant, causing serious neurological and developmental effects in humans. Recent epidemiological studies have indicated that ingestion of MeHg in fish during pregnancy can result in neuroethological effects in the offspring. However, the mechanism underlying the MeHg-toxicity is not fully understood. To elucidate the mechanisms of toxicity of MeHg and of defense against MeHg, we searched for factors that determine the sensitivity of yeast cells to MeHg, and found that overexpression of Cdc34, a ubiquitin-conjugating enzyme (E2) that is a component of the ubiquitin-proteasome (UP) system, induces a resistance to MeHg toxicity in both yeast and human cells. The UP system is involved in the intracellular degradation of proteins. When Cdc34 is overexpressed in cells, ubiquitination reactions are activated and the degradation of certain proteins by the UP system is enhanced. Therefore, it seems likely that certain as-yet-unidentified proteins that increase MeHg toxicity might exist in cons and that toxicity might be reduced by the enhanced degradation of such proteins, mediated by the UP system, when Cdc34 is overexpressed. SCF ubiquitin-ligase is a component of UP system and consists of Skpl, the scaffold protein Cdc53, the RING-finger protein Hrt1, and one member of the family of F-box proteins. The F-box proteins directly bind to the substrates and are the determinants of substrate specificity of SCF. Therefore, we searched for the f-box protein that cofers resistance to MeHg, and found that overexpression of Hrt3 or Yi1224w induced resistance to MeHg toxicity in yeast cells. Since the protein(5) that enhance toxicity of MeHg might plausibly be induced in substrates of both f-box proteins, we next searched for substrate proteins that are recognized by Hrt3 or Y1r224w using two-hybrid screen. We found that Did3 or Crsl interacts with Hrt3; and Eno2 interacts with Yir224w. The yeast cells that overexpressed each those proteins showed hypersensitivity to MeHg, respectively, indicating that those proteins enhance the MeHg toxicity. Both Dld3 and Eno2 are proteins involved in the synthesis of pyruvate, and overexpression of both proteins might induce increase in interacellular levels of pyruvate. Deletion of Yi1006w that transports pyruvate into the mitochondria induced aresistance to MeHg. These results suggest that the promotion of the pyruvate irdlowinto the mitochondria might enhance MeHg toxicity. This study providesimportant keyfor the elucidauon of the molecular mechanism of MeHg toxicity.

• The Microorganisms and Industry
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• v.19 no.2
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• pp.2-10
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• 1993

이 총론에서는 cell cycle의 조절에 관계하는 p34cdc kinase의 특성과 기질 그리고 cell cycle에서의 역할을 살펴보고, 또 cell cycle에서와 여러가지 세포내의 현상에 중요한 역할을 하는 것으로 알려진 casein kinase II의 특성과 기질 그리고 cell cycle에서의 역할을 살펴보고자 한다. 그리고 이런 효소들을 연구하는 데 필수적인 방법이나 시약들로 소개하고자 한다.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.1042-1052
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• 2010

This study aimed to evaluate the protective effects of Mundongcheongpye-eum (MCE) on elastase-induced lung injury. The extract of MCE was treated to A549 cells and elastase-induced lung injury mice model. Then, various parameters such as cell-based cyto-protective activity and histopathological finding were analyzed. MCE showed a protective effect on elastase-induced cytotoxicity in A549 cells. This effect was correlated with analysis for caspase 3 levels, collagen and elastin contents, protein level of cyclin B1, Cdc2, and Erk1/2, and gene expression of TNF-${\alpha}$ and IL-$1{\beta}$ in A549 cells. MCE treatment also revealed the protective effect on elastase-induced lung injury in mice model. This effect was evidenced via histopathological finding including immunofluence stains against elastin, collagen, caspase 3, and protein level of cyclin B1, Cdc2, and Erk1/2 in lung tissue. These data suggest that MCE has a pharmaceutical properties on lung injury. This study would provide an scientific evidence for the efficacy of MCE for clinical application to patients with chronic obstructive pulmonary disease.