• BMB Reports
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• 제48권3호
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• pp.166-171
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• 2015

We previously demonstrated that resveratrol and clofarabine elicited a marked cytotoxicity on malignant mesothelioma (MM) MSTO-211H cells but not on the corresponding normal mesothelial MeT-5A cells. Little is known of the possible molecules that could be used to predict preferential chemosensitivity on MSTO-211H cells. Resveratrol and clofarabine induced downregulation of Mcl-1 protein level in MSTO-211H cells. Treatment of cells with cycloheximide in the presence of proteasome inhibitor MG132 suggested that Mcl-1 protein levels were regulated at the post-translational step. The siRNA-based knockdown of Mcl-1 in MSTO-211H cells triggered more growth-inhibiting and apoptosis-inducing effects with the resultant cleavages of procaspase-3 and its substrate PARP, increased caspase-3/7 activity, and increased percentage of apoptotic propensities. However, the majority of the observed changes were not shown in MeT-5A cells. Collectively, these studies indicate that the preferential activation of caspase cascade in malignant cells might have important applications as a therapeutic target for MM.

• 상하수도학회지
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• 제22권1호
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• pp.159-168
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• 2008

A special field experiment has been carried out from March 2001 to June 2001 at the Changhowon in Kyunggi to investigate a better methodology for the estimation of dry deposition of pollutions applicable in Korea. In this study, dry deposition plate was used to measure of total and water soluble acidic mass fluxes, and CPRI(Coarse Particle Rotary Impactor), CI(Cascade Impactor) were also used to measure ambient concentrations in various particle size ranges. Sehmel-Hodgson model was used to estimate dry depostion velocity and Weibull probability distribution function was applied to get generalized particle size distribution for the size fractioned concentration data sampled by CPRI and CI. Atmospheric dry deposition fluxes of mass and ionic matters estimated by the various techniques(one-step, multi-step, equi-concentration, subdivision for only the coarse particle range, applying Weibull distribution function, etc.) were compared to flux data sampled by DDP. It was found out that the deposition fluxes estimation methodology calculated by the each particle size range devided by particle size distribution characteristics and the rapidly changed points of deposition velocity using Weibull probability distribution function was the most applicable.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.848-854
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• 2006

In this study, a computational analysis system has been developed in order to investigate flow-induced vibration(FIV) phenomenon for general stator-rotor cascade configurations. Relative movement of the rotor with respect to stator is reflected by modeling independent two computational domains. Fluid domains are modeled using the unstructured grid system with dynamic moving and local deforming methods. Unsteady, Reynolds-averaged Navier-Stokes equations with one equation Spalart-Allmaras and two-equation SST $k-\omega$ turbulence models are solved for unsteady flow problems. A fully implicit time marching scheme based on the Newmark direct integration method is used flow computing the coupled governing equations of the fluid-structure interaction problem. Detailed FIV responses for different flow conditions are presented with respect to time and vibration characteristics are also physically investigated in the time domain.

• Journal of Microbiology and Biotechnology
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• 제16권1호
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• pp.46-51
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• 2006

The inhibitory effects of flavanone derivatives on Helicobacter pylori (HP) growth, infection and VacA toxininduced vacuolation were investigated. Among flavanones tested, ponciretin potently inhibited the growth of HP with a MIC value of 0.01 mg/ml and VacA toxin-induced vacuolation in HeLa cells with $IC_{50}$ value of 0.078 mM. However, other flavanones inhibited neither HP growth nor VacA toxininduced vacuolation. All flavanones tested did not inhibit HP infection to KATO III cells. Ponciretin also inhibited activation of procaspase-3 to caspase-3 in HeLa cell induced by HP VacA toxin, but did not affect Bax and Bcl-2 protein levels. These findings indicate that ponciretin inhibits growth as well as vacuolation by HP VacA toxin, which induces cell death via proteolytic activation of a cascade of caspases.

• 한국미생물·생명공학회지
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• 제28권2호
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• pp.87-91
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• 2000

미생물로부터 U937 세포주의 etoposide에 유발된 apoptosis 저해물질을 탐색한 결과 곰팡이 F80834 균주를 선발하였다. 균주 배양액으로부터 저해물질을 분리한 후 UV, EIMS, 1H-NMR, 13C-NMR, DEPT 등의 기기분석을 실시한 결과 terrein으로 동정되었다. 이 물질은 $IC_{50}$ $20\mu\textrm{g}/ml$의 농도로 U937 세포주의 etoposide에 의한 caspase 3 유도를 저해하였다. Etoposide에 의한 세포의 사멸도 IC50 $10\mu\textrm{g}/ml$ 농도로 저해하였으며, 동일한 농도 조건에서 단독 처리시 세포 독성을 나타내지 않았다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7439-7444
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• 2013

Aim: ATF3, a member of the ATF/CREB family of transcription factors, has been found to be selectively induced by calcineurin/NFAT inhibition and to enhance keratinocyte tumor formation, although the precise role of ATF3 in human skin cancer and possible mechanisms remain unknown. Methods: In this study, clinical analysis of 30 skin cancer patients and 30 normal donors revealed that ATF3 was accumulated in skin cancer tissues. Functional assays demonstrated that ATF3 significantly promoted skin cancer cell proliferation. Results: Mechanically, ATF3 activated Stat3 phosphorylation in skin cancer cell through regulation of p53 expression. Moreover, the promotion effect of ATF3 on skin cancer cell proliferation was dependent on the p53-Stat3 signaling cascade. Conclusion: Together, the results indicate that ATF3 might promote skin cancer cell proliferation and enhance skin keratinocyte tumor development through inhibiting p53 expression and then activating Stat3 phosphorylation.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.153-156
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• 2006

A turbine stage consists of a stator and rotor. A stator provides the required inlet flow conditions so that a rotor can produce the necessary power. Passing wakes generated at the trailing edge of a stator make an interaction with a rotor. In the present study, this interaction flow mechanism is investigated using the numerical analysis. In case of the large gap distance between the stator and rotor, the stator and rotor flow analysis can be separated. First, only the stator flow field is solved. Second, the rotor flow field is solved including the passing wake information from the stator analysis. The passing wake experiences the shearing as it approaches to the rotor leading edge. And it is chopped when it strikes the rotor body. After that, the chopped wakes becomes the prolongation as it goes downstream. Also, the aerodynamic characteristics with the variation of the gap distance between a stator and rotor was investigated. Pressure jumps due to the passing wakes result in the pressure and lift loss and it gets stronger with the closer gap distance. This unsteady effect proves to be directly related to the fatigue and noise in turbomachinery and this study would be helpful to investigate such fields.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.619-622
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• 2002

It has been recognized that the flow in the blade passage of an axial turbomachinery rotor is very complex and is influenced by various flow phenomena, of which the tip leakage flow passing through the gap between rotor blade tip and casing plays a significant role. The losses produced due to the existence of the clearance have been known to be a large contributor of the rotor overall losses. Despite several experimental studies on non-rotating blade in the cascade configuration, and on actual rotating blades, the detailed nature of the complex flow phenomena associated with tip leakage, however, remains largely unresolved. Thus, a single-stage compressor test rig was built and measurements were taken at upstream and downstream of the rotor of this compressor at the aerodynamics laboratory of University of New South Wales. A five-hole probe and a hot-wire probe were used to measure mean and fluctuating flow parameters. The results show that tip leakage losses rise rapidly beyond tip gap of 0.01 Furthermore, the present project also identifies the regions in the wake behind the rotor of the axial compressor where such losses are concentrated. These results should be useful in the better design of rotors for improved performance of axial compressor.

• 한국수산과학회지
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• 제44권3호
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• pp.216-224
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• 2011

Capsosiphon fulvescens is well-known green sea algae that, in recent years, has been proposed as a potential anticancer drug. In this study, we found that C. fulvescens glycoprotein (Cf-GP) had pro-apoptotic effects on human gastric carcinoma cells. By SDS-PAGE, we confirmed that C. fulvescens extract contained a glycoprotein. Using H33342 staining, we found that the Cf-GP caused cell death in a does-dependent manner, while an MTS assay showed decreased cellular viability due to induction of apoptosis. To determine the effect of Cf-GP on apoptosis-related cellular events, cells were treated with Cf-GP and the expression of several apoptosis-related protein was determined by Western blotting. Our results indicate that Cf-GP activated both a caspase cascade and PARP, which is a substrate of caspase-3, caspase-8 and the Bcl-2 family proteins. In addition, we assessed caspase-3, and -8 activation and annexin V staining. Our results revealed a cell cycle arrest, itself leading to an increased percentage of sub-G1 cells. Our findings indicate that Cf-GP may be a source of bio-functional material with therapeutic effects on human gastrointestinal cancer.

• 대한한의학회지
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• 제23권4호
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• pp.125-139
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• 2002

Objectives: The purpose of this investigation is to evaluate the effects of Woohwangcheongsim-won and to study the mechanism for neuronal death protection in OGD (oxygen-glucose deprivation) model with embryonic day 20 (E20) cortical cells of a rat (Sprague Dawley). Methods: E20 cortical cells were dissociated in neurobasal media and grown for 14 days in vitro (DIV). On 14 DIV, Woohwangcheongsim-won was added to the culture media for 72 hrs. On 17 DIV, cells were given an oxygen-glucose deprivation shock (2hrs and 4hrs) and further incubated in normoxia for another three days. On 20 DIV, Woohwangcheongsim-won's effects for neuronal death protection were evaluated by LDH assay and the mechanisms were studied by Bcl-2, Bak, Bax, caspase family. Results & Conclusions: 1. This study indicates that Woohwangcheongsim-won's effects for neuronal death protection in OGD model is confirmed by LDH assay in culture method of embryonic day 20(E20) cortical neuroblasts. 2. Woohwangcheongsim-won's mechanisms for neuronal death protection in OGD model are to restrain inflow of cytochrome c into cellularity caused by Bcl-2 increase (2hrs and 4hrs), to reduce the caspase cascade initiator caspase-8 (4hrs).