• 한국군사과학기술학회지
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• 제22권3호
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• pp.392-400
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• 2019

This paper provides a fin actuation system of missile based on electromagnetic-spring mechanism to miniaturize the system and lower the cost. Compared with proportional electro-mechanical actuators, the output of Electromagnetic-Spring Actuators(EMSA) has two or three discrete states, but the mechanical configuration of EMSA is simple since it does not need power trains like gears. The simple mechanism of EMSA makes it easy to build small size, low cost, and relatively high torque actuators. However, fast response time is required to improve the dynamic performance and accuracy of missiles since bang-off-bang operation of EMSA affects the flight performance of missile. In this paper the development of EMSA including parameter optimization and mathematical modeling is described. The simulation results using Simulink and experimental test results of prototype EMSAs are presented.

• The Plant Pathology Journal
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• 제28권1호
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• pp.75-80
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• 2012

$Potato$ $virus$ $X$ (PVX) contains $cis$-acting elements including stem-loop 1 (SL1) RNA at the 5' region; SL1 is conserved among all potexviruses. The SL1 at the positive-sense RNA, SL1(+), is required for PVX RNA replication, cell-to-cell movement, and translation. Previous research demonstrated that SL1(+) RNA also serves as the origin of assembly for encapsidation of PVX RNA. To identify the essential sequences and/or regions for capsid protein (CP) subunit recognition within SL1(+) RNA, we used electrophoretic mobility shift assays (EMSA), UV cross-linking, and yeast three-hybrid analyses. The EMSA and UV cross-linking analyses with PVX CP subunits and RNA transcripts corresponding to the SL1(+) RNA showed that the SL1(+) RNA formed complexes with CP subunits. We also conducted EMSA and yeast three-hybrid analyses with RNAs containing various mutations of SL1(+) RNA elements. These analyses indicated that SL1(+) RNA is required for the interaction with PVX CP and that the RNA sequences located at the loop C and tetra loop of the SL1(+) are crucial for CP binding. These results indicate that, in addition to being important for RNA accumulation, the SL1(+) RNA from the 5' region of the PVX genome is also required for specific binding of PVX CP.

• The Plant Pathology Journal
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• 제22권2호
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• pp.139-146
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• 2006

The 3' region of Potato virus X (PVX) has the 74 nt 3'-nontranslated region (NTR) that is conserved among all potexviruses and contains several cis-acting elements for minus-strand and plus-strand RNA accumulation. Three stem-loop structures (SL1-SL3), especially formation of SL3 and U-rich sequence of SL2, and near upstream elements in the 3' NTR were previously demonstrated as important cis-acting elements. To Investigate the binding of these cis-acting elements within 3' end with host protein, we used the electrophoretic mobility shift assays (EMSA) and UV-cross linking analysis. The EMSA with cellular extracts from tobacco and RNA transcripts corresponding to the 150 nt of the 3' end of PVX RNA showed that the 3' end of PVX formed complexes with cellular proteins. The specificity of protein binding was confirmed through competition assay by using with 50-fold excess of specific and non-specific probes. We also conducted EMSA with RNAs containing various mutants on those cis-acting elements (${\Delta}10$10, SL3B, SL2A and ${\Delta}21$; J Mol Biol 326, 701-720) required for efficient PVX RNA accumulation. These analyses supported that these cis-acting elements are required for interaction with host protein(s). UV-cross linking analysis revealed that at least three major host proteins of about 28, 32, and 42 kDa in mass bound to these cis-elements. These results indicate that cis-acting elements from 3' end which are important for minus and plus-strand RNA accumulation are also required for host protein binding.

• 생명과학회지
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• 제19권9호
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• pp.1289-1293
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• 2009

원암단백질로 알려진 Human cervical cancer oncogene (HCCR)은 발암억제 단백질인 p53과 작용하여 다양한 암조직에서 암의 유발을 촉진한다. 그러나, 아직 정확한 발암 유도기전이 알려져 있지 않다. 이러한 의문을 해소하기 위한 일환으로 본 연구에서는 HCCR의 발현이 어떻게 조절되는지를 조사하였다. 이를 위해 먼저 HCCR 5' 쪽의 promoter 영역을 분리하여 Luciferase assay법을 이용하여 K562, HEK293, A549 세포에서 분석하였고, Promoter의 -370에서 -406사이 36bp의 첨가로 promoter활성이 의미 있게 억제됨을 관찰하였다. 또한, 36 bp만을 포함하는 probe를 이용한 mobility shift assays (EMSA)에서 핵단백질이 결합함을 관찰하였고, 컴퓨터를 이용한 분석에서 TG-interacting factor (TGIF)에 대한 consensus sequences 존재함을 관찰하였다. TGIF 만을 포함하는 probe (TC)와 돌연변이를 유발한 probe (mTG)를 이용한 EMSA에서 이 자리에 TGIF가 결합함을 보였다. 또한, TGIF 자리에 돌연변이를 유발하면(pGL3-mTGIF) 발현의 억제가 회복됨을 관찰하였다. 본 연구에서는 HCCR promoter의 특성을 분석하였고, 이 과정에서 -390에서 -366 사이에 TGIF 전사인자가 결합하여 전사활성을 조절함을 증명하였다.

• BMB Reports
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• 제38권4호
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• pp.474-480
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• 2005

Curcumin, a major active component of turmeric, has been identified as an inhibitor of the transcriptional activity of activator protein-1 (AP-1). Recently, it was also found that curcumin and synthetic curcumin derivatives can inhibit the binding of Jun-Fos, which are the members of the AP-1 family, to DNA. However, the mechanism of this inhibition by curcumin and its derivatives was not disclosed. Since the binding of Jun-Fos dimer to DNA can be modulated by redox control involving conserved cysteine residues, we studied whether curcumin and its derivatives inhibit Jun-Fos DNA binding activity via these residues. However, the inhibitory mechanism of curcumin and its derivatives, unlike that of other Jun-Fos inhibitors, was found to be independent of these conserved cysteine residues. In addition, we investigated whether curcumin derivatives can inhibit AP-1 transcriptional activity in vivo using a luciferase assay. We found that, among the curcumin derivatives examined, only inhibitors shown to inhibit the binding of Jun-Fos to DNA by Electrophoretic Mobility Shift Assay (EMSA) inhibited AP-1 transcriptional activity in vivo. Moreover, RT-PCR revealed that curcumin derivatives, like curcumin, downregulated c-jun mRNA in JB6 cells. These results suggest that the suppression of the formation of DNA-Jun-Fos complex is the main cause of reduced AP-1 transcriptional activity by curcuminoids, and that EMSA is a suitable tool for identifying inhibitors of transcriptional activation.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3405-3409
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• 2013

The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.

• 한국산학기술학회논문지
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• 제16권11호
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• pp.7237-7243
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• 2015

응급실은 병원으로 입원하는 주요 경로로서, 감염환자의 1차적 내원의 가능성이 높은 곳이다. 국내에서 질병관리본부가 2009년에 제정한 "응급실에서의 감염관리 표준지침"이 응급실 감염환자 관리 방안과 표준시설기준을 규정하고 있으나 각 병원 응급실의 감염환자 시설은 병원마다 차이가 있고 지침에 따른 일관된 감염환자 관리시설을 갖추었다고 보기 어렵다. 본 연구는 응급실에서의 감염관리 표준지침의 실효성을 알아보기 위해 법적 강제성을 갖는 "응급의료에 관한 법률"과 비교하여, 첫째 지침이 법률 시설기준에 반영된 여부를 분석하였고, 둘째 2009년 전후에 신축 또는 개축한 응급실들을 분석대상으로 하여 각 시설기준 항목들의 반영여부를 파악하였다. 그 결과 지침과 법률 시설기준의 상호연관성은 없었다. 분석대상 응급실들의 시설은 법적기준을 모두 충족한 반면 지침의 감염관리시설은 선별적으로 적용되어 있었고, 설치 항목들이 건축년도에 관계없이 분석대상 응급실에 대부분 적용되어 "응급실에서의 감염관리 표준지침"의 제정과는 무관한 것으로 나타났다. 본 연구 결과는 향후 응급실의 감염관리시설의 법적기준 체계 보완에 참고자료로 활용 될 수 있을 것이다.

• Animal cells and systems
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• 제3권3호
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• pp.311-317
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• 1999

Prolactin (PRL) was reported to be locally synthesized in many brain areas including the hypothalamus, thalamus (TH) and hippocampus (HIP). In the pituitary lactotrophs, PRL synthesis is dependent upon a pituitary-specific transcription factor, Pit-1. In the present study, we attempted to identify Pit-1 or Pit-1-like protein in brain areas known as the synthetic sites of PRL. Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analysis showed the same Pit-1 transcripts in brain areas such as the medial basal hypothalamus (MBH), preoptic area (POA), TH, and HIP with the Pit-1 transcripts in the anterior pituitary (AP). Electrophoretic mobility shift assay (EMSA) was run with nuclear protein extracts from brain tissues using a double strand oligomer probe containing a putative Pit-1 binding domain. Shifted bands were found in EMSA results with nuclear proteins from MBH, POA, TH and HIP. Specific binding of the Pit-1-like protein was further confirmed by competition with an unlabeled cold probe. Antisense Pit-1 oligodeoxynucleotide (Pit-1 ODN), which was designed to bind to the Pit-1 translation initiation site and block Pit-1 biosynthesis, was used to test Pit-1 dependent brain PRL transcription. Two nmol of Pit-1 ODN was introduced into the lateral ventricle of a 60-day old male rat brain. RNA blot hybridization and in situ hybridization indicated a decrease of PRL mRNA signals by the treatment of Pit-1 ODN. Taken together, the present study suggests that Pit-1 may play an important role in the transcriptional regulation of local PRL synthesis in the brain.

• Journal of Acupuncture Research
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• 제25권2호
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• pp.75-89
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• 2008

목적 : 후박(厚朴)(Magnolia obovata)에서 추출한 낮은 농도의 obovatol 약침액의 RAW264.7 세포에서 LPS로 유발된 염증, $TNF-{\alpha}$로 유발된 human colon carcinoma SW620 및 HCT116 세포의 세포증식에 대한 영향과 그 기전을 살펴보고자 하였다. 방법 : RAW264.7 세포에서 LPS로 염증을 유발하고 낮은 농도의 obovatol 약침액을 처리한 후 cell viability, NO 생성량, iNOS와 COX-2의 발현, $NF-{\kappa}B$활성, 전사능력을 관찰하기 위해 WST-1 assay, NO determination assay, western blot analysis, EMSA, luciferase activity assay를 시행하였고, HCT116, SW620 세포에 $TNF-{\alpha}$로 증식을 유도하고 낮은 농도의 obovatol 약침액을 처리한 후 cell growth, apoptosis 및 apoptosis와 연관된 $NF-{\kappa}B$의 활성 변화를 관찰하기 위해 WST-1, Cell morphogy test, DAPI staining and TUNEL assay, EMSA, luciferase activity assay를 시행하였다. 결과 : 1. RAW264.7 세포에서 낮은 농도의 obovatol 약침액 처리는 $NF-{\kappa}B$의 활성 및 전사능력을 낮추고 iNOS와 COX-2의 발현과 NO 생성을 감소시켜 LPS로 유발된 염증을 억제하였다. 2. HCT116, SW620 세포에서 낮은 농도의 obovatol 약침액 처리는 $NF-{\kappa}B$의 활성을 낮추어 세포자멸사를 촉진함으로써 $TNF-{\alpha}$로 유발된 암세포의 성장을 억제하였다. 결론 : 이상의 결과는 낮은 농도의 obovatol 약침액이 항염 및 인간 전립선암세포주인 SW620, HCT116에 대한 증식억제 효과가 있음을 입증한 것이며, 향후 이를 바탕으로 한 생체 연구에서의 긍정적인 결과는 obovatol 약침액이 만성염증성 질환 및 대장암의 예방과 치료에 대한 효과적인 치료제 개발에 초석이 될 것으로 기대된다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5659-5663
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• 2012

To investigate the expression of hPOT1 in the HeLa cell line and screen point mutations of hpot1 in different tumor tissues a two step osmotic method was used to extract nuclear proteins. EMSA was performed to determine the expression of hPOT1 in the HeLa cell line. PCR was also employed to amplify the exon14 sequence of the hpot1 gene in various of cancer tissues. A SV gel and PCR clean-up system was performed to enrich PCR products. DNAStar was used to analyse the exon14 sequence of the hpot1 gene. hPOT1 was expressed in the HeLa cell line and the signal was gradually enhanced as the amount of extracted nuclear proteins increased. The DNA fragment of exon14 of hpot1 was successfully amplified in the HeLa cell line and all cancer tissues, point mutations being observed in 2 out of 3 cases of endometrial cancer (66.7%) despite the hpot1 sequence being highly conserved. However, the sequence of hpot1 exon14 do not demonstrate point mutations in most cancer tissues. Since hPOT1 was expressed in HeLa cell and the probability of gene point variants was obviously higher in endometrial cancer than other cancers, it may be involved in the pathogenesis of gynecological cancers, especially in cervix and endometrium.