• Proceedings of the Korean Society of Toxicology Conference
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• 2005.05a
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• pp.171-171
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• 2005

• 한국지구물리탐사학회:학술대회논문집
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• 2011.10a
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• pp.197-198
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• 2011

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.144-144
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• 2003

Phosphatidylinositol 3-kinase (PI3K) and Rac play important roles that regulate cellular functions including cell survival and .migration. In the present study, we investigated the functional roles of PI3K and Rac1 pathways in H-ras-induced invasive phenotype and motility of MCF10A cells.(omitted)

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5535-5538
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• 2012

Background: There have been case reports of oral squamous cell carcinoma arising from gingival overgrowth induced by phenytoin - an antiepileptic drug. However, a detailed analysis for the presence of mutations in p53 and ras genes, which are the two most frequently mutated genes in cancers, in phenytoin induced gingival overgrowth tissues has hitherto not been performed. Methods: Cellular DNA isolated from twenty gingival overgrowth tissues collected from patients undergoing phenytoin therapy were amplified using primers for p53 (exons 5-8) and H-ras (exons 1-2) genes. The PCR amplicons were then gel purified and subjected to direct sequencing analysis to screen for mutations. Results: Direct sequencing of twenty samples of phenytoin induced gingival growth did not identify mutations in any of the exons of p53 and H-ras genes that were analyzed. Conclusion: Our result indicates that mutational alteration of p53 and H-ras genes is infrequent in phenytoin induced gingival growth, which thus suggests a non malignant nature of this pathology. The findings in the present study are clinically significant as a large number of epileptic patients are treated with phenytoin.

• Journal of Environmental Science International
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• v.22 no.5
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• pp.571-580
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• 2013

In this study, compared with the result of water surface elevation and water velocity on the establishment of river maintenance basic plan and result of HEC-GeoRAS based GIS, and after use the result of water surface elevation and velocity were observed in the Han stream on Jeju island, analysis 2 dimensional stream flow. the lateral hydraulic characteristics and curved channel of the stream were analyzed by applying SMS-RMA2 a 2 dimensional model. The results of the analysis using HEC-RAS model and HEC-GeoRAS model indicated that the distribution ranges of water surface elevation and water velocity were similar, but the water surface elevation by section showed a difference of 0.7~2.18 EL.m and 0.63~1.16 EL.m respectively, and water velocity also showed differences of maximum 1.58m/sec and 2.67m/sec. SMS-RMA2 analysis was done with the sphere of Muifa the typhoon as a boundary condition, and as a result, water velocity distribution was found to be 1.19 through 3.91 m/sec, and the difference of lateral water velocity in No. 97 through 99 the curved channel of the stream was analyzed to be 1.59 through 2.36 m/sec. In conclusion it is anticipated that the flow analysis of 2 dimension model of stream can reflect the hydraulic characteristics of the stream curved channel or width and shape, and can be applied effectively in the establishment of river maintenance basic plan or management and designing of stream.

• Experimental and Molecular Medicine
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• v.50 no.11
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• pp.12.1-12.12
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• 2018

Drugs targeting the epidermal growth factor receptor (EGFR), such as cetuximab and panitumumab, have been prescribed for metastatic colorectal cancer (CRC), but patients harboring KRAS mutations are insensitive to them and do not have an alternative drug to overcome the problem. The levels of ${\beta}$-catenin, EGFR, and RAS, especially mutant KRAS, are increased in CRC patient tissues due to mutations of adenomatous polyposis coli (APC), which occur in 90% of human CRCs. The increases in these proteins by APC loss synergistically promote tumorigenesis. Therefore, we tested KYA1797K, a recently identified small molecule that degrades both ${\beta}$-catenin and Ras via $GSK3{\beta}$ activation, and its capability to suppress the cetuximab resistance of KRAS-mutated CRC cells. KYA1797K suppressed the growth of tumor xenografts induced by CRC cells as well as tumor organoids derived from CRC patients having both APC and KRAS mutations. Lowering the levels of both ${\beta}$-catenin and RAS as well as EGFR via targeting the $Wnt/{\beta}$-catenin pathway is a therapeutic strategy for controlling CRC and other types of cancer with aberrantly activated the $Wnt/{\beta}$-catenin and EGFR-RAS pathways, including those with resistance to EGFR-targeting drugs attributed to KRAS mutations.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06a
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• pp.494-497
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• 2011

함수 복귀 예측은 이론적으로 오버플로가 발생하지 않는 한도 내에서 100%의 정확도를 보여야 한다. 하지만, 투기적 실행을 지원하는 현대 마이크로프로세서 환경 하에서는 잘못된 실행 경로로의 수행 결과를 무효화 할 때 RAS의 오염이 발생하며, 이는 함수 복귀 주소의 예측 실패로 이어진다. 본 논문에서는 이러한 RAS의 오염을 방지하기 위하여 RAS 재명명 기법을 제안한다. RAS 재명명 기법은 RAS의 스택을 소프트 스택과 하드 스택으로 나누어 관리한다. 소프트 스택은 투기적 실행에 의한 데이터의 변경을 복구할 수 있는 항목을 관리하고, 하드 스택은 소프트 스택의 크기 제한으로 겹쳐쓰기가 일어나는 데이터 가운데 이후에 재사용될 데이터를 관리하는 구조로 구성된다. 제안된 기법을 모의실험 한 결과, RAS 오염방지 기법이 적용되지 않은 시스템과 비교하여 함수 복귀 예측 실패를 약 1/90로 감소시켰으며, 최대 6.95%의 IPC 향상을 가져왔다.

• BMB Reports
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• v.51 no.5
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• pp.225-229
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• 2018

In humans, hormonal regulation is crucial for the preparation of uterine environment leading to either successful implantation or menstrual cycle. Estrogen is a pivotal female steroid hormone that regulates the uterine dynamics along with progesterone in the estrous and menstrual cycles in humans. Estrogen signals act via nuclear estrogen receptor or membrane-bound receptor. The membrane-bound estrogen receptor plays a crucial role in the rapid response of estrogen in the uterine epithelium. Recently, RASD1 has received attention as a novel signal transducer of estrogen in various systems including female reproductive organs. In this review, we discuss the regulation of estrogen and RASD1 signaling in the uterus and also provide insights into RAS as a novel signaling molecule in repeated implantation failure.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.80-80
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• 2002

Cyclooxygenase-2 (COX-2) is an inducible enzyme expressed in response to a variety of cytokines. The presence of oncogenic ras has been associated with sustained induction of COX-2, which confers resistance to apoptosis. Contrary to the above notion, we found that MCF10A-ras cells treated with an anti-tumor agent, ET-18-O-$CH_3$, underwent apoptosis as revealed by proteolytic cleavage of poly(ADP-ribose)polymerase, pro-caspase 3 activity, and TUNEL staining, while the same treatment caused an increased expression of COX-2 as well as the elevated production of prostaglandin E$_2$(PGE$_2$).(omitted)

• Journal of Powder Materials
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• v.10 no.3
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• pp.190-194
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• 2003

Thin Ag films deposited onto $SiO_2/Si$ substrates by DC magnetron sputtering and thereafter annealed ,it temperatures 100-50$0^{\circ}C$ are investigated by scanning tunneling and atomic forte microscopy. It is shown that the film surface topography and microstructure are considerably changed as a result of annealing. To provide a quantitative estimation of the surface topography changes of Ag films the surface fractal dimension was calculated. Elasticity and hardness of the films are studied by a nanoindentation technique. The films are found to have value of elastic modulus close to that of bulk silver while their hardness and yield stress are essentially higher.