• 대한세포병리학회지
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• 제9권1호
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• pp.15-20
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• 1998

Mutant form of the p53 gene product is abnormally accumulated in the nuclei of the tumor cells due to prolonged half life, and readily detected by immunohistochemical methods. To determine the positivity rate of p53 in body cavity fluid according the primary site and histological types of tumors and the utility of p53 immunostaining as an adjunct in the diagnosis of malignancy, we reviewed 69 effusions, including pleural effusion, ascitic fluid, and pericardial fluid, that were diagnosed as overt malignancy and 21 effusions of suspicious malignancy, immunohistochemistry was performed on paraffin-embedded cell blocks using a monoclonal antibody to p53 supressor gene product(Clone DO7) and a standard avidin-biotin complex technique with a citrate buffer antigen retrieval solution. The results were as follows; of the 46 pleural effusions with overt malignancy, 22 were immunopositive for p53 protein; of the 21 ascitic fluids with overt malignancy, 5 were positive for p53. Positivity rates according to the primary sites of tumors were 18 of 34(52.9%), 8 of 21(38.1%), 1 of 9(11.1%) cases of the tumors of the lung, GI tract, and ovary, respectively. According to the histologic types of lung cancer, 11 cases(61.6%) were positive out of 18 adenocarcinomas, 2 of 5 large cell undifferentiated carcinomas, and 1 of 2 small cell undifferentiated carcinomas. Of 21 cases of suspicious malignancy, 6 were positive for p53 and all of them(6/6) were confirmed as adenocarcinoma of the lung or GI tract. These findings indicate that p53 immunostaining using paraffin embedded cell block is useful diagnostic and prognostic marker in body fluid cytology although negative immunostaining does not exclude malignancy.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.26-32
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• 2000

Monospecific red tide by a toxic dinoflagellate belonging to the genus Alexandrium occurred at Chindong Bay in the southern coast of Korea and continued from April 6th to 15th in 1997. The ratio of its cell number to total phytoplankton cell number was much higher than $95\%$. This organism was identified as Alexandrium tamarense, although slight morphological differences were found comparing to the original and successive descriptions of the species. We found neither anterior nor posterior attachment pores in these cells of the bloom population. The occurrence of red tide caused by A. tamarense was first reported in Korea. Its plate formula is Po, Pc, 4', 6"c, 8s, 5"' and 2"". Thecal plates are thin with pore-like ornamentation. In those plates, the anterior part of the first apical plate (1') is narrower and its posterior end has sometimes a block-like accessory, but this variation was considered within the range of the morphological variability of this taxon. The cell density during the red tide exhibited a wide range of variation by the depth of water column, ranging from $2\times10^6$ cells$l^{-1}$ to $5\times10^6$ cells·$l^{-1}$. Water temperature varied from 11.8 to $12.3^{\circ}C$. Toxicity of A. tamarense during red tide was measured as $8.8\times10^5$. $MU\;\cdot\;cell^{-1}$ by mouse bioassay.

• 한국음향학회지
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• 제18권2호
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• pp.53-60
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• 1999

본 논문에서는 CSH(Current Sample-and-Hold)와 CCMP(Current Comparator)로 구성된 1.5-비트 비트 셀을 이용한 새로운 구조의 CMOS IADC(Current-mode Analog-to-Digital Convener)를 제안한다. 전체적인 IADC의 선형성 향상을 위하여 CFT(Clock Feedthrough)가 제거된 9-비트 해상도 CSH를 설계하여 각 비트 셀 전단에 배치하였다. 제안한 IADC를 구성하는 비트 셀은 2개의 래치 CCMP를 사용하기 때문에 디지털 교정 로직이 간소화되고 소비전력이 감소된다. 또한 IADC를 구성하는 모든 블록들의 회로는 MOS 트랜지스터로만 설계되었기 때문에 혼성모드 집적화에 유리하다. 제안한 IADC를 현대 0.8 ㎛ CMOS 파라미터로 HSPICE 시뮬레이션 결과, 20Ms/s에서 100 ㎑의 입력 신호에 대한 SNR은 43 dB로 7-비트의 해상도를 만족하였고 27 ㎽의 소비전력 특성을 나타냈다.

• BMB Reports
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• 제46권11호
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• pp.533-538
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• 2013

The expression of matrix metalloproteinases (MMPs) produced by cancer cells has been associated with the high potential of metastasis in several human carcinomas, including breast cancer. Several pieces of evidence demonstrate that protein tyrosine phosphatases (PTP) have functions that promote cell migration and metastasis in breast cancer. We analyzed whether PTP inhibitor might control breast cancer invasion through MMP expression. Herein, we investigate the effect of 4-hydroxy- 3,3-dimethyl-2H benzo[g]indole-2,5(3H)-dione (BVT948), a novel PTP inhibitor, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. The expression of MMP-9 and cell invasion increased after TPA treatment, whereas TPA-induced MMP-9 expression and cell invasion were decreased by BVT948 pretreatment. Also, BVT948 suppressed NF-${\kappa}B$ activation in TPA-treated MCF-7 cells. However, BVT948 didn't block TPA-induced AP-1 activation in MCF-7 cells. Our results suggest that the PTP inhibitor blocks breast cancer invasion via suppression of the expression of MMP-9.

• 대한수의학회지
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• 제45권4호
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• pp.495-500
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• 2005

The nucleoside analogue gemcitabine (2', 2-difluorideoxycytide) is potential against a wide variety of solid tumors and considered to be one of the most active drugs in the treatment of non-small cell lung cancer (NSCLC). In this study, we investigated the signals of gemcitabine-induced apoptosis, especially in point of caspase pathway in A549. We exposed A549 cells to gemcitabine for dose/time dependent manner and the results showed that gemcitabine induced apoptotic cell death in a time/dose-dependent manner. We also treated to gemcitabine and Z-VAD-fmk as a pan-caspase inhibitor for 24 hours. Gemcitabine alone induced 35.3% cell death, and co-treatment with gemcitabine and Z-VAD-fmk induced 15.1% apoptotic cell death. Our results demonstrated that Z-VAD-fmk as a pan-caspase did not completely block the gemcitabine-induced apoptosis. Western blotting analysis showed that gemcitabine increased caspase-3, active caspase-8, p21 and p53 protein expressions in A549. Co-treatment with Z-VAD-fmk completely blocked caspase-3 and active caspase-8 protein expressions, but did not change the level of p21 and p53 protein expressions. Our data indicate that gemcitabine induced apoptosis through caspase-dependent and -independent pathways in A549.

• 대한예방한의학회지
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• 제12권2호
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• pp.51-59
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• 2008

Objectives : Buplueri Radix (BR), used medical plant in Korea traditional medicine, contains various compounds, including a series of triterpene saponins known as saikosaponins. We performed this study for the protective effect of BR against oxidative damage induced by 1,2,4-benzentriol(BT) in human lymphocytes. Methods : In order to investigate the protective effect of BR against carcinogens, genotoxicity induced by benzene metabolite, BT were performed using cytokinesis-block micronucleus(CBMN) assay and comet assay. Results : The frequency of micronucleus at 25, 50 and $100{\mu}M$ concentration of BT were $8{\pm}2.36$, $23{\pm}2.31$, $35{\pm}4.17$ respectively. In addition of BR with concentration of 25 and $50{\mu}g/mL$, MN frequencies were significantly decreased. According to comet assay, BT induced DNA damage in a dose-dependent manner at concentration of 10 and 50 while BT with BR treatment decreased DNA breakage. No genotoxicity was observed by BR($25{\sim}50{\mu}g/mL$) treatment alone on DNA breakage. Since BT can induce DNA damage through the generation of reactive oxygen species(ROS), we examined the level of ROS in human lymphocytes treated with BT and/or BR using DCF-DA, ROS-sensitive probe. The generation of ROS in BT-treated cells was also observed, and BR addition inhibited the level of BT-induced DNA damage. Conclusions : From above results it is suggested that BR could protect the cell and DNA from pro-oxidant effect by ROS by BT

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.411.2-411.2
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• 2014

The design of DNA nanostructures is of fundamental importance, the intrinsic value of DNA as a building-block material lies in its ability to organize other bio-molecules with nanometer-scale spacing. Here, we report the fabrication of DNA scaffolds with nano-pores (<10 nm size) that formed easily without the use of additives (i.e., avidin, biotin, polyamine, or inorganic materials) into large-scale structures by assembling DNA molecules at near room temperature ($30^{\circ}C$) and low pH (~5.5). Protein immobilization results also confirmed that a fibronectin (FN) proteins/large scale DNA scaffolds/aminopropylytriethoxysilane (APS)/SiO2/Si substrate with high sensitivity formed in a well-defined manner. The DNA scaffolds can be applied for use with DNA-based biochips, biophysics, and cell biology.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.182.3-183
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• 2003

(-)-Antofine is phenanthroindolizidine alkaloid being isolated from Cynanchum vincetoxicum. It has powerful cytotoxicity toward drug-sensitive KB-3-1 and multidrug resistant KB-V1 cancer cell line. We have successfully accomplished stereoselective total synthesis by using palladium catalyzed Stille coupling of l0-bromomethyl-2,3 ,6-trimethoxy-phenanthrene and (R)-(E)-4-(tributylstannanyl)but-3-en-2-o1, Overmann rearrangement of imidate, and RCM(ring-closing metathesis) for construction of pyrrolidine.

• Asian Pacific Journal of Cancer Prevention
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• 제13권10호
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• pp.4993-4998
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• 2012

Vanillic acid, a vegetable phenolic compound, is a strong antioxidant. The aim of the present study was to determine its effects on mitomycin C-induced DNA damage in human blood lymphocyte cultures in vitro, both alone and in combination with mitomycin C (MMC). The cytokinesis block micronucleus test and alkaline comet assay were used to determine genotoxic damage and anti-genotoxic effects of vanillic acid at the DNA and chromosome levels. MMC induced genotoxicity at a dose of $0.25{\mu}g/ml$. Vanillic acid ($1{\mu}g/ml$) significantly reduced both the rates of DNA damaged cells and the frequency of micronucleated cells. A high dose of vanillic acid ($2{\mu}g/ml$) itself had genotoxic effects on DNA. In addition, both test systems showed similar results when tested with the negative control, consisting of dimethyl sulfoxide (DMSO) in combination with vanillic acid ($1{\mu}g/ml$)+MMC. In conclusion, vanillic acid could prevent oxidative damage to DNA and chromosomes when used at an appropriately low dose.

• 대한임상독성학회지
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• 제15권2호
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• pp.107-115
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• 2017

Purpose: Glehnia littoralis has been used to treat ischemic stroke, phlegm, cough, systemic paralysis, antipyretics and neuralgia. The pharmacological mechanisms of Glehnia littoralis include calcium channel block, coumarin derivatives, anticoagulation, anti-convulsive effect, as well as anti-oxidant and anti-inflammatory effects. Alpha-amanitin (${\alpha}$-amanitin) is a major toxin from extremely poisonous Amanita fungi. Oxidative stress, which may contribute to severe hepatotoxicity was induced by ${\alpha}$-amanitin. The aim of this study was to investigate whether Glehnia littoralis ethyl acetate extract (GLEA) has the protective antioxidant effects on ${\alpha}$-amanitin -induced hepatotoxicity. Methods: Human hepatoma cell line HepG2 cells were pretreated in the presence or absence of GLEA (50, 100 and $200{\mu}g/ml$) for 4 hours, then exposed to $60{\mu}mol/L$ of${\alpha}$-amanitin for an additional 4 hours. Cell viability was evaluated using the MTT method. AST, ALT, and LDH production in a culture medium and intracellular MDA, GSH, and SOD levels were determined. Results: GLEA (50, 100 and $200{\mu}g/ml$) significantly increased the relative cell viability by 7.11, 9.87, and 14.39%, respectively, and reduced the level of ALT by 10.39%, 34.27%, and 52.14%, AST by 9.89%, 15.16%, and 32.84%, as well as LDH by 15.86%, 22.98%, and 24.32% in culture medium, respectively. GLEA could also remarkably decrease the level of MDA and increase the content of GSH and SOD in the HepG2 cells. Conclusion: In the in vitro model, Glehnia littoralis was effective in limiting hepatic injury after ${\alpha}$-amanitin poisoning. Its antioxidant effect is attenuated by antidotal therapy.