• 한국자기학회:학술대회 개요집
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• 한국자기학회 1998년도 추계연구발표회 논문개요집
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• pp.68-69
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• 1998

• 생명과학회지
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• 제26권10호
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• pp.1214-1217
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• 2016

Rebamipoide는 위궤양과 위염치료에 쓰이는 위보호제로 임상에서 사용되고 있지만 위암에서의 역할에 대해서는 알려지바가 거의 없다. 헬리코박토 파일로리(Helicobacter pylori)의 주요독성인자인 CagA는 위암의 발생과 관련이 있다. CagA는 위암세포에서 NFκB의 활성을 증가시켜 PLD1 단백질의 발현을 증가시킴으로써 위암세포의 증식과 침윤을 유도한다. Rebamipide는 NFκB의 활성을 억제함으로써 H. pylori의 CagA에 의해 유도되는 PLD1의 발현을 저해하는것으로 규명되었다. 게다가, rebamipide는 H. pylori의 CagA에 의해 유도되는 β-catenin과 그 표적 유전자로서 인 암줄기세포 마커 단백질의 발현을 증가시킴으로써 위암줄기세포의 자가재생능력을 감소시킨다. 또한 rebamipide는 항암제 내성을 극복하는 화학감수성을 증가시켜서 위암생성을 감소시키는 것으로 나타났다. 그래서 rebamipide는 위암치료제로서의 잠재적 효능을 가지고 있는 약물로서의 가능성이 제시되고 있다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1998년도 춘계연구발표회 논문개요집
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• pp.84-85
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• 1998

• 한국미생물·생명공학회지
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• 제22권4호
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• pp.333-339
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• 1994

In order to screen microorganisms producing phospholipase D (PLD) [EC 3.1.4.4], culture broths of about 900 strains of soil bacteria were subjected to examine for the PLD activity. When the hydrolytic activity of PLD (H-activity) in the supernatant was determined, 64 strains produced PLD more than 0.3 unit/ml and all of them were actinomycetes. Among 26 culture broths tested, 6 ones had transphosphatidylation activity (T-activity) of 30~68%. When the strains except one were cultivated on 3 different media at 30$\circ$C for 3 days under aerobic condition, strain # 1090 on medium B (yeast extract 1%, peptone 1%, glucose 1.5%, glycerol 1%, CaCO$_{3}$ 0.4%, and pH 7.2) produced PLD with much higher H- and T-activity, which were 8.3 units/ml and 76.3%, respectively. Subsequently, time course of PLD production of the strain # 1090 during cultivation with aeration of 1 v/v/m and agitation of 400 rpm at 30$\circ$C for 5 days on medium B in jar fermentor was investigated. H-activty of PLD reached almost maximum (about 9 units/ml) after 32 hours and maximal T-activity was found to be about 80%.

• BMB Reports
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• 제34권2호
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• pp.182-187
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• 2001

Phospholiapse D (PLD), and phosphatidic acid generated by it, have been implicated in receptor-mediated intracellular signaling. Carbachol (CCh) is known to activate PLD1, and protein kinase C (PKC) is known to mediate in this signaling pathway In recent reports (Kim et al., 1999b; Kim et al., 2000), we published our observations of the direct phosphorylation of PLD1 by PKC and we described the phosphorylation-dependent regulation of PLD1 activity. In this study, we investigated the phasphorylation and compartmentalization of PLD1 in terms of CCh signaling in M3 muscarinic receptor (M3R)-expressing COS-7 cells. CCh treatment of COS-7 cells transiently coexpressing PLD1 and M3R stimulated PLD1 activity and induced direct phosphorylation of PLD1 by PKC. The CCh-induced activation and phosphorylation of PLD1 was completely blocked upon pretreatment of the cells with PKC-specific inhibitors. We looked at the localization of the PLD1 phosphorylation by PKC and found that PLD1 was mainly located in the caveolin-enriched membrane (CEM) fraction. Based on these results, we conclude that CCh induces the activation and phosphorylation of PLD1 via PKC and that the phosphorylation of PLD1 occurs in caveolae.

• Molecules and Cells
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• 제40권11호
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• pp.805-813
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• 2017

The role of phospholipase D (PLD) in cancer development and management has been a major area of interest for researchers. The purpose of this mini-review is to explore PLD and its distinct role during chemotherapy including anti-apoptotic function. PLD is an enzyme that belongs to the phospholipase super family and is found in a broad range of organisms such as viruses, yeast, bacteria, animals, and plants. The function and activity of PLD are widely dependent on and regulated by neurotransmitters, hormones, small monomeric GTPases, and lipids. A growing body of research has shown that PLD activity is significantly increased in cancer tissues and cells, indicating that it plays a critical role in signal transduction, cell proliferation, and anti-apoptotic processes. In addition, recent studies show that PLD is a downstream transcriptional target of proteins that contribute to inflammation and carcinogenesis such as Sp1, $NF{\kappa}B$, TCF4, ATF-2, NFATc2, and EWS-Fli. Thus, compounds that inhibit expression or activity of PLD in cells can be potentially useful in reducing inflammation and sensitizing resistant cancers during chemotherapy.

• 대한전자공학회논문지TC
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• 제42권2호
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• pp.75-80
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• 2005

본 논문에서는 5.8GHz 무선랜에 적용할 수 있는 전력증폭기를 설계 및 제작하였다. 제작된 전력증폭기는 2단으로 구성되며 측정결과 중심주파수 5.8GHz에서 21.6dBm의 PldB 출력전력과 100MHz 대역에서 17.6dB 이득과 -17.8dB 이하의 입력반사손실을 얻었다. 설계된 전력증폭기의 왜곡과 출력 ACPR 관계를 분석하기위해, 최대 54Mbps의 전송속도를 가지는 IEEE 802.11a OFDM 변조부와 송신부를 모델링하였다. 전력증폭기의 비선형특성은 behavioral model을 이용하여 AM-to-AM과 AM-to-PM으로 모델링하였으며, 위상 왜곡에 따른 출력스펙트럼 특성을 해석하였다. IEEE 802.11a 무선랜 시스템의 요구 출력스펙트럼 마스크를 만족하기위한 PldB로부터 back-off값을 구하기 위하여 위상왜곡에 따른 전력증폭기의 ACPR 특성을 시뮬레이션하고 사전왜곡방식을 이용하여 증폭기의 위상왜곡을 변화시키며 측정한 결과와 시뮬레이션 특성을 비교 제시하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제7권4호
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• pp.211-215
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• 2003

To examine the localization pattern of phospholipase D2 (PLD2) in the pancreatic islet (the islet of Langerhans) depending on species, we conducted a morphological experiment in the rat and guinea pig. Since individual islets display a typical topography with a central core of B cell mass and a peripheral boundary of A, D, and PP cells, double immunofluorescent staining with a panel of antibodies was performed to identify PLD2-immunoreactive cells in the islets PLD2 immunoreactivity was mainly present in A and PP cells of the rat pancreatic islets. And yet, in the guinea pig, PLD2 immunoreactivity was exclusively localized in A cells, and not in PP cells. These findings suggest a possibility that PLD2 is mainly located in A cells of rodent pancreatic islets, and that the existence of PLD2 in PP cells is not universal in all species. Based on these results, it is suggested that PLD2 may play a significant role in the function of A and/or PP cells via a PLD-mediated signaling pathway.

• 한국어병학회지
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• 제17권2호
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• pp.131-137
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• 2004

본 실험은 넙치 (Paralichthys olivaceus) 간으로부터 membrane부분에 존재하는 PC 가수분해 효소의 특성에 대해 조사하였다. 먼저 간 조직을 초고속 원심 분리기와 nonion-detergent인 1% triton X - 100을 이용하여 membrane 부분을 분리하였으며, Heprain-Sepharose CL-6B 칼럼과 Heparin-5PW 칼럼을 이용하여 분리정제 하였다. 얻어진 PC 가수분해효소에 대한 반응 ․ 생성물을 확인하기 위해 autoradiography를 실시하였다. 지용성 부분의 결과에서 transphosphatidylation 반응의 결과물인 PEtOH을 형성하는 것으로 보아 PC-PLD임을 알 수 있었다. 얻어진 PC 가수분해효소에 대한 생화학적 특성을 조사한 결과 적정 pH가 6.5이하인 산성 조건 및 $37^\circ{C}$의 배양온도에서 최고 활성을 나타내었으며, 이가 이온들에 대한 영향의 경우 칼슘은 1.67mM 농도에서 최고 활성을 나타냈으나, 마그네슘은 활성에 영향을 미치지 않았다. 각종 세포막 기질에 대한 영향을 조사한 결과 PC는 $0.75\mu{M}$, PIP2는 $2.35\mu{M}$, PE는 $26.8\mu{M}$ 농도에서 최고 활성을 나타내었다. 이상의 결과부터 넙치 간조직의 막층부분에 존재하는 PC를 가수분해효소는 PC-PLD가 존재함을 알 수 있었다.

• Journal of electromagnetic engineering and science
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• 제4권4호
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• pp.143-149
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• 2004

This paper describes characteristics of the single-balanced low IF resistive FET mixer for the digital beam forming(DBF) receiver. This DBF receiver based on the direct conversion method is designed with Low IF I and Q channel. A radio frequency(RF), a local oscillator(LO) and an intermediate frequency(IF) considered in this research are 1950 MHz, 1940 MHz and 10 MHz, respectively. Super low noise HJ FET of NE3210S01 is considered in design. The measured results of the proposed mixer are observed IF output power of -22.8 dBm without spurious signal at 10 MHz, conversion loss of -12.8 dB, isolation characteristics of -20 dB below, 1 dB gain compression point(PldB) of -3.9 dBm, input third order intercept point(IIP3) of 20 dBm, output third order intercept point(OIP3) of 4 dBm and dynamic range of 30 dBm. The proposed mixer has 1.0 dB higher IIP3 than previously published single-balanced resistive and GaAs FET mixers, and has 3.0 dB higher IIP3 and 4.3 dB higher PldB than CMOS mixers. This mixer was fabricated on 0.7874 mm thick microstrip $substrate(\varepsilon_r=2.5)$ and the total size is $123.1\;mm\times107.6\;mm$.