• Title/Summary/Keyword: PEP

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A Study on the Evaluation of Pro-environmental Potential of Streams in Sunchon City (중.소도시 하천의 친환경적 활용 잠재력 평가에 관한 연구 -전남 순천시 하천을 사례로-)

  • 정정채;이상석
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.1
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    • pp.96-112
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    • 1998
  • This study aims to evaluate the potential of pro-environmental application(PEP) in streams conceptualized ecological conservation and recreational use to be in harmony with. The main content of research are to clarify the PEP, to establish the evaluation model, and to evaluate 3 streams(Dongchon, Seokhyunchon, Okchon) in Sunchon city. Researchers introduced 12 evaluation items(water quality, water quantity, vegetation-water area, vegetation conservation, streamscape, neighborhood landscape, stream width, optimum area, nearby landuse, facility in stream, distance from user, obstacle to acces) by 5 scales to evaluate the characteristics of natural and artificial factors in stream area and nearby area. Also to decide the weight of items, researchers surveyed the opinion of 22 landscape architects experienced stream-plan through delphi method. Lastly the pro-environmental potential on streams were calculated by the ecological potential and recreational potential indices to be standardized and indicidual sections in streams were divided 5 grades on the basis of PEP. The result of this study are as follows; 1) The evaluation model of PEP was constructed by 4 steps, such as the decision of weight, the measurement of scale, the calculation of potential indices, the gradation of individual sections in streams. 2) The ecological potential were highly influenced by natural factor such as water quality, vegetation conservation, vegetation-water area, but on the other hand the recreational potential were influenced by optimum area, distance from user, water quantity, obstacle to access. 3) The factors such as vegetation conservation, optimum area, nearby landuse, distance from user were function as discernment factors to evaluate relatively ecological and recreational potential. and water quality, water quantity, vegetation -water area, neighborhood landscape were acted as important items to decide PEP.

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Characterization of Alanine Scanning Mutants of a Peptide Specifically Binding to $TiO_{2}$ Nanoparticles ($TiO_{2}$ Nanoparticle에 특이적으로 결합하는 Peptide의 Alanine Scanning Mutant의 성질에 관한 연구)

  • Seo, Min-Hee;Chael, Hee-Kwon;Myung, Heejoon
    • Microbiology and Biotechnology Letters
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    • v.33 no.4
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    • pp.319-321
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    • 2005
  • We have previously reported the isolation and characterization of peptides binding to $TiO_{2}$ nanoparticles from phage display peptide libraries. One of the peptides (PEP9) was selected and mutant peptide-displaying phages were produced by alanine scanning mutagenesis. The mutant phages were subjected to binding analysis to $TiO_{2}$ nanoparticles. When the proline at residue 4 was substituted by alanine, the binding activity was reduced to $10\%$ of that of wild type PEP9. Substitution of valine at residue 2, serine at residue 3, and isoleucine at residue 5 also decreased the binding to $40\%$. Based on these observations, we concluded that the three dimensional structure generated by residues 2-5 was the critical factor for the binding between PEP9 and the nanoparticle.

Solution Structure of a GSK 3$\beta$ Binding Motif, A $AXIN^{pep}$

  • Kim, Yong-Chul;Jung, JIn-Won;Park, Hee-Yong;Kim, Hyun-Yi;Lee, Weon-tae
    • Journal of the Korean Magnetic Resonance Society
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    • v.9 no.1
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    • pp.38-47
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    • 2005
  • Axin is a scaffold protein of the APC/axin/GSK complex, binding to all of the other signalling components. Axin interacts with Glycogen synthase kinase 3$\beta$ (GSK 3$\beta$) and functions as a negative regulator of Wnt signalling pathways. To determine the solution structure of the GSK3$\beta$ binding regions of the axin, we initiated NMR study of axin fragment comprising residues 3$Val^{388} - Arg^{401}$using circular dichroism (CD) and two-dimensional NMR spectroscopy. The CD spectra of 3$axin^{pep}$ in the presence of 30% TFE displayed a standard 3$\alpha$-helical conformation, exhibiting the bound structure of 3$axin^{pep}$ to GSK3$\bata$. On the basis of experimental restraints including $NOE_s$, and $^3J_{HN\alpha} $ coupling constants, the solution conformation of $axin^{pep}$ was determined with program CNS. The 20 lowest energy structures were selected out of 50 final simulated-annealing structures in both water and TFE environment, respectively. The $RMSD_s$ for the 20 structures in TFE solution were 0.086 nm for backbone atoms and 0.195 nm for all heavy atoms, respectively. The Ramachandran plot indicates that the $\varphi$, $\psi$ angles of the 20 final structures is properly distributed in energetically acceptable regions. $Axin^pep$ in aqueous solutions consists of a stable $\alpha$-helix spanning residues form $Glu^{391}$ to $Val^{391} $, which is an interacting motif with GSK3$\beta$.

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Comparative study of linear and cyclic forms of apoptosis-targeting peptide

  • Ha, Yeong Su;Soni, Nisarg;Huynh, Phuong Tu;Lee, Byung-Heon;An, Gwang Il;Yoo, Jeongsoo
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.2 no.2
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    • pp.96-102
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    • 2016
  • Apoptosis, a genetically determined process of programmed cell death, is considered a vital component of various processes including normal cell turnover, animal development, and tissue homeostasis. It has a crucial role in many medical disorders and hence the development of non-invasive imaging tool is highly demanded. Recently, we have developed a peptide-based radioactive probe (ApoPep-1) for apoptosis detection. In that work the potential of probe for apoptosis detection was verified, however in vivo stability of radiolabeled peptide was not enough to monitor apoptosis for extended period. In current study, we prepared cyclic ApoPep-1 peptides to improve the stability of origianl linear ApoPep-1 and carried out direct comparison studies in vitro and in vivo. A targeting efficacy of newly synthesized cyclic ApoPep-1 peptide for apoptosis was confirmed in acute myocardial infarct model.

Effect of Memory-enhancing Herbal Extract (YMT_02) on Modulating Pentraxin, PEP-19 and Transthyretin gene Expression in Rat Hippocampus (육미지황탕가미방에 의한 흰쥐 기억력 향상과 관련된 Hippocampus 부위의 특이 유전자 발현에 대한 연구)

  • Sim Dea Sik;Rho Sam Woong;Lee Jin Woo;Lee Eun A;Cho Chong Woon;Bae Hyun Su;Shin Min Kyu;Hong Moo Chang
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.3
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    • pp.684-692
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    • 2003
  • The herbal extract(YMT_02) is a modified extracts from Yukmijihwang-tang(YMJ) to promote memory-enhancing. The YMJ extracts has been widely used as replenishing yin and tonifying the kidneys herbal medicine for hundred years ia Asian countries. The purpose of this study is to: 1) quantitatively evaluate the memory-enhancing effect of YMT_02 by passive avoidance test, 2) statistical evaluation of candidate gene expression (pentraxin. PEP-19, transthyretin) in rat hippocampus. The hippocampi of YMT_02 and control group were dissected and mRNA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied to Real Time PCR. The results were as follows : 1) passive avoidance test showed enhancing memory retentin by YMT_02 treatment, 2) expression of pentraxin, that accelerate degenerating of neuronal cell, was significantly decreased, 3) the mRNA of genes that has been known to be associated with protecting neuronal cell degeneration, such as PEP-19 and transthyretin, were significantly increased upon YMT_02 treatment. From above results, the administration of YMT_02 which tonify the function of Kidneys could enhance the ability of memory and learning. In addition, the administration of YMT_02 enhance memory retention through modulating particular gene (pentraxin, PEP-19, transthyretin) expressions in hippocampu.

Performance Analysis on the Multiple Trellis Coded CPFSK for the Noncoherent Receiver without CSI (채널 상태 정보를 사용하지 않는 비동기식 복조기를 위한 다중 격자 부호화 연속 위상 주파수 변조 방식의 성능분석)

  • 김창중;이호경
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.10C
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    • pp.942-948
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    • 2003
  • In this paper, we analyze the performance of multiple trellis coded modulation applied to continuous phase frequency shift keying (MTCM/CPFSK) for the noncoherent receiver without channel state information (CSI) on the interleaved Rician fading channel. In this system, the squared cross-correlation between the received signal and a candidate signal is used as the branch metric of the Viterbi decoder. To obtain the bit error performance of this system, we analyze the approximated pairwise error probability (PEP) and the exact PEP. We also derive the equivalent normalized squared distance (ENSD) and compare it with the ENSD of the noncoherent receiver with perfect CSI. Simulation results are also provided to verify the theoretical performance analysis.

A Dynamic ACK Generation Scheme to Improve Web Traffic Performance over Satellite Internet (위성 인터넷에서 웹 트래픽의 성능 향상을 위한 동적 응답 패킷 생성 기법)

  • Park, Hyun-Gyu;Lee, Ji-Hyun;Lim, Kyung-Shik;Jung, Woo-Young
    • IEMEK Journal of Embedded Systems and Applications
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    • v.1 no.2
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    • pp.64-72
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    • 2006
  • The long propagation delay over satellite internet causes degradation of TCP performance in slow start phase. Especially, web traffic performance is greatly reduced by low throughput in slow start phase. To improve web traffic performance, we propose the Dynamic ACK Generation Scheme which generates ACKs and considers sender RTO in PEP (Performance Enhancing Proxy). The Normal ACK generation mechanism improves TCP throughput, and also decreases sender RTO. if PEP stops generating ACKs, TCP performance will be reduced by frequent RTO expiration. To solve this problem, our scheme adjusts RTO using ACK generation interval. And it supports retransmission mechanism for loss recovery in PEP. The results of the performance analysis provide a good evidence to demonstrate the efficiency of our mechanisms over satellite internet.

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Cardiac systolic time intervals and heather index measured by impedance cardiography during postural changes (체위변화시 심장의 수축기 시간간격 및 Heather Index의 변화)

  • 고성경;김창규;김덕원
    • Journal of the Ergonomics Society of Korea
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    • v.11 no.1
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    • pp.67-79
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    • 1992
  • Cardiac systolic time intervals (STLs) and Heather index (HI) were used to access changes in left ventricular function of six male subjects exposed to postural changes,$0^{\circ}C$, ${\pm}2^{\circ}C$, ${\pm}45^{\circ}C$, ${\pm}90^{\circ}C$, Significant prolongation of the pre-ejection period (PEP) and PEP/ LVET ratio, shortening of the left ventricular ejection time (LVET), STI, HI and $1/PEP^{2}$were observed during exposure to both $+45^{\circ}C $ and $+90^{\circ}C $But the values measured during $-45^{\circ}C $ and$-90^{\circ}C $ were reversed. Changes in fluid shift, filling volume, preload, after load and sympathetic activities may account for the observed findings. Early response of cardiac foctions was recorded using impedance cardiography. This method is very simple but accurate. Thus it will be useful in this aerospace and work physiology. In conclusion, STIs appear to provide reliable noninvasive method for examining changes of cardiac function during exposure to postural changes.

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Investigation of DPPH Radical Scavenging and Pyolyl Endopeptidase Inhibitory Activities of Plant Extracts (천연 식물자원에서 DPPH 라디칼 제거능과 Prolyl Endopeptidase 활성 저해능 탐색)

  • Lee Young Min;Kim Dae Ik;Lee Sung Hyeon;Cho Soo Muk;Chun Hye Kyung;Park Hong Ju;Lee Yeon Sook
    • The Korean Journal of Community Living Science
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    • v.16 no.4
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    • pp.95-102
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    • 2005
  • The present study was performed to investigate the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging and Proly1 endopeptidase (PEP) inhibitory activities of plant extracts. The whole extract of Fragaria yezoensis inhibited the DPPH radical by $90.4\%$ and the stem of Gingko biloba, Gardenia jasminoides for. grandiflora and Rhododendron yedoensa var. poukhanene, the loaves of Rhododendron mucronulatum var. ciliatum, Gardenia jasminoides for. grandiflora and Corylus sieboldiana var. mandshurice, the fruit of Cornus officinalis, and the root of Gingko biloba showed high DPPH radical scavenging activities. In the case of PEP inhibitory activities, high inhibition was observed in the whole Plant of Fragaria ananassa, Fragaria yezoensis and Hypericum erectum, the stem of Actinidia arguta and Rhododendron yedoensa var. poukhanese, the leaves of Rhododendron yedoensa var. poukhanense and Rosa davurica, the fruit of Cornus officinalis. and the root of Acer okamotoanum. There was significant correlation (P=0.000) between DPPH radical scavenging and prolyl endopeptidase inhibitory activities, thus some of plant extracts such as whole Fragaria yezoensis, fruit of Cornus officinalis had high activities in both DPPH-scavenging and prolyl endopeptidase inhibition. Therefore, it is required to examine the mechanical interaction between DPPH-scavenging and prolyl endopeptidase inhibitory activities and further studying plant extracts with both these activities is desired to develop agents for preventing and treating of Alzheimer's disease.

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PEP-1-p18 prevents neuronal cell death by inhibiting oxidative stress and Bax expression

  • Kim, Duk-Soo;Sohn, Eun-Jeong;Kim, Dae-Won;Kim, Young-Nam;Eom, Seon-Ae;Yoon, Ga-Hyeon;Cho, Sung-Woo;Lee, Sang-Hyun;Hwang, Hyun-Sook;Cho, Yoon-Shin;Park, Jin-Seu;Eum, Won-Sik;Choi, Soo-Young
    • BMB Reports
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    • v.45 no.9
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    • pp.532-537
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    • 2012
  • P18, a member of the INK4 family of cyclin-dependent kinase inhibitors, is a tumor suppressor protein and plays a key cell survival role in a variety of human cancers. Under pathophysiological conditions, the INK4 group proteins participate in novel biological functions associated with neuronal diseases and oxidative stress. Parkinson's disease (PD) is characterized by loss of dopaminergic neurons, and oxidative stress is important in its pathogenesis. Therefore, we examined the effects of PEP-1-p18 on oxidative stress-induced SH-SY5Y cells and in a PD mouse model. The transduced PEP-1-p18 markedly inhibited 1-methyl-4-phenyl pyridinium-induced SH-SY5Y cell death by inhibiting Bax expression levels and DNA fragmentation. Additionally, PEP-1-p18 prevented dopaminergic neuronal cell death in the substantia nigra of a 1-methyl-4-phenyl-1,2,3,6,-tetrahydropyridine-induced PD mouse model. These results indicate that PEP-1-p18 may be a useful therapeutic agent against various diseases and is a potential tool for treating PD.