• Journal of Plant Biology
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• v.39 no.2
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• pp.85-92
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• 1996

Small GTP-binding proteins are divided into three major group: Ras, Rho and Ypt/Rab. They have the conserved regions designed G1 to G5 that are critical in GDP/GTP exchange, GTP-induced conformational change and GTP hydrolysis. We isolated and characterized genomic DNA or cDNAfragments encoding G1 to G3 domains of small GTP-binding protein Rab and Rho from several plant species using two different PCR-based cloning strategies. Seven rab DNA fragments were isolated from 4 different plants, mung-bean, tobacco, rice and pepper using two degenerate primers corresponding to the GTP-binding domain G1 and G3 in small GTP-binding proteins. The amino acid sequences among these rab DNA fragments and other known small GTP-binding proteins shows that they belong to the Ypt/Rab family. Six rho DNA fragments were isolated from 5 different plants, mung-bean, rice, Arabidopsis, Allium and Gonyaulax using the nested PCR method that involves four degenerate primers corresponding to the GTP-binding domain G1, G3 and G4. The rho DNA fragments cloned show more than 90% homology to each other. Sequence comparison between plant and other known Rho family genes suggests that they are closely related (67 to 82% amino acid identity). Sequence analysis and southern blot analysis of rab and rho in mung-bean suggest than thses genes are encoded by multigene family in mung-bean.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.59-73
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• 1980

A detailed procedure was described for the isolation of cratine kinase (ATP-Creatine phosphotransferase, E. C. 2. 7. 3. 2.) from the muscle of the snake Bungarus fasciatus. The original isolation procedure of Kuby et al. for the rabbit muscle enzyme has been modified and extended to include a chromatographic step. The properties of the enzyme have been investigated and kinetic constants for the reverse reactions determined as the followings: 1) A molecular weight of the enzyme was determined by gel filteration on Sephadex G-100 and by electrophoresis on SDS-polyacrylamide was 86,000. 2) Two reactive sulphydryl groups were detected with dithiobis nitrobenzoic acid (DTNB). 3) The nucleotide substrate specificity in the reverse reaction was determined as ADP*2'-dADP＞GDP＞XDP＞UDP with magnesium as the activating metal ion. 4) The order of the metal specificity in the reverse reaction Mg>Mn>$Ca{\sim}Co$ was determined with ADP as substrate. 5) A detailed kinetic analysis was carried out in the reverse direction with $MaADP^-$ as the nucleotide substrate. Initial velocity and product inhibition studies($MaADP^{2-}$ competitive with respect to MgADP- and noncompetitive with respect to $N-phosphorycreatine^{2-}$ ; Creatine competitive with respect to $N-phosphorycreatine^{2-}$ and noncompetitive with respect to Ma $ADP^-)$ indicated that the reaction obeyed a sequential mechanism of the rapid equilibrium random type.

• Journal of Korean Society of Rural Planning
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• v.28 no.4
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• pp.11-18
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• 2022

Recently, the relevance of the Air Quality Index considering major factors related to the air environment and the local economy and community was analyzed in abraod. In Korea, a comprehensive air-quality index has been proposed. In this study, the comprehensive air-quality index and the index that can integrate Gross Domestic Product per capita were summarized as regional attractiveness. As a result of the analysis, Ulsan, Chungnam, Seoul, Chungbuk, and Jeonnam had the highest Gross domestic product per capita, and Jeju, Gyeongnam, and Gyeongbuk had the best Comprehensive air-quality index, and Ulsan had the highest attractiveness. As a result of the correlation analysis, it was found that there was no correlation between the two variables, Gross domestic product per capita and Comprehensive air-quality index, because various factors such as topographical characteristics, hazardous substances, and local government's efforts were not taken into account. As a result of sensitivity analysis, Ulsan had the highest sensitivity and variance for Gross domestic product per capita and Comprehensive air-quality index. As for the relative ratio of attractiveness between regions, Ulsan's attractiveness was 2.95 times that of Daegu's, indicating a large difference between regions.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.109-118
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• 1996

The Salmonella rfb gene encoding for the biosynthesis of the oligosaccharide-repeating units of the O-antigenic determinants was cloned and sequenced. A set of nucleotide primers(a forward and reverse) was selected to target a defined region of the guanosine diphospho-mannose(GDP-Man) pyrophosphorylase synthase gene : rfbM of Salmonella C serogroup. The primer set was used to develop a PCR-based rapid and specific detection system for Salmonella C1 serogroup. Amplification bands of predicted size(1,422bp) were generated from 11 different Salmonella C1 isolates. The bands were verified to be specific for the C1 serogroup by Southern blot analysis using reference homologous DNA specificity was further confirmed by the lack of reactivity with heterologous DNA derived from non-salmonella members of the family enterobacteriaeceae. A specificity of 100% was deduced along with a very high sensitivity shown by a detection limit of 1fg of a purified DNA template. The isolated DNA sequence was found to be 99.8% homologous to S montevideo but the related primers amplified with the predicted band sizes with all the Salmonella C1 serogroups tested. It is concluded that the PCR protocol based on the rfbM gene from S cholerasuis is optimal fast and specific for the detection of Salmonella C1 serogroup and also the corresponding probe is suitable for rapid detection of all Salmonella C1 serogroup DNA tested. This technology should facilitate the identification of contaminated pig products and for any other products contaminated with the Salmonalla C1 serogroup. The immediate impact of this developed method will be in the area of food safety of pig products with the potential prospect for adaptation to other food inspection technologies.

• Journal of Life Science
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• v.29 no.9
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• pp.1010-1015
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• 2019

The interstitial cells of Cajal (ICCs) are the pacemaker cells in the gastrointestinal (GI) tract. In the present study, the effects of olanzapine, an atypical antipsychotic agent, on pacemaker potentials in cultured ICCs from the small intestine of the mouse were investigated. The whole-cell patch-clamp configuration was used to record pacemaker potentials from cultured ICCs. Olanzapine produced pacemaker depolarizations in a concentration-dependent manner in current clamp mode. Methoctramine, a muscarinic $M_2$ receptor antagonist, did not inhibit olanzapine-induced pacemaker depolarizations, whereas 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) muscarinic $M_3$ receptor antagonist did inhibit it. When guanosine 5'-[${\beta}$-thio] diphosphate (GDP-${\beta}$-S; 1 mM) was in the pipette solution, olanzapine-induced pacemaker depolarization was blocked. Also, low $Na^+$ solution externally eliminated the generation of pacemaker potentials and inhibited the olanzapine-induced pacemaker depolarizations. Additionally, the nonselective cation channel blocker, flufenamic acid, inhibited the olanzapine-induced pacemaker depolarizations. Pretreatment with U-73122, an active phospholipase C (PLC) inhibitor, also eliminated the generation of pacemaker potentials and suppressed the olanzapine-induced pacemaker depolarizations. These results suggested that olanzapine modulates the pacemaker potentials through muscarinic $M_3$ receptor activation by G protein-dependent external $Na^+$ and PLC pathway in the ICCs. Therefore, olanzapine could affect intestinal motility through ICCs.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.278-280
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• 2007

우리나라는 지난 94년간 1.5도 상승하여 전지구 온난화추세를 상회하였다. 기온뿐만 아니라 강수량 역시 변화하였는데 변동폭이 크기는 하나 장기적으로 증가하는 경향으로 20세기초에 비해 상대적으로 기온이 높고 강수량도 많은 특성을 보인다. 평균적인 기후변화추이와 더불어 특히 최근 10년($1996{\sim}2005$년)은 1850년 이후 지구평균기온이 가장 높았던 기간으로, 세계적으로 열파, 홍수, 가뭄, 태풍 등 기상이변에 의한 인명과 재산 피해, 생물종의 멸종 등 사회경제적 피해가 막대하였다. 우리나라 역시 폭염, 호우등의 빈번한 출현으로 급격해지는 온난화추세 영향을 반영하였는데 이러한 기후 변화양상을 파악하기 위하여 우리나라의 최근 10년간 기후 특성과 계절별 현상일수의 변화를 분석하였다. 최근 10년(1996-2005년) 우리나라 기후변화의 특성을 보면 우리나라(15개 관측지점자료)는 평균기온이 과거 30년$(1971{\sim}2000)$ 평균대비 $0.6^{\circ}C$ 상승하였다. 계절별로 봄은 평년대비 $0.7^{\circ}C$, 여름은 $0.4^{\circ}C$, 가을은 $0.6^{\circ}C$, 겨울은 $0.7^{\circ}C$ 상승하여 봄과 겨울의 상승폭이 가장 크다. 연강수량은 30년 평균대비 최근 10년 강수량은 11% 증가하였고 특히 여름은 증가폭이 가장 커서 18% 증가하였다. 계절에 따라 다양한 기상현상의 변화도 나타났다. 3월 이후에 나타나는 늦서리의 종료일은 평균적으로 3월 말경에 나타났는데 최근 10년에는 3월 중순으로 2주 앞당겨졌고 이 추세는 특히 1993년 이후 뚜렷하다. 늦서리의 발생일수도 평균 4일 정도 줄었다. 일평균기온 $20^{\circ}C$이상인 날은 평년에 비해 최근 10년 동안 약 2일 증가하여 여름 시작시기가 빨라지고 있음을 알 수 있다. 일최저기온이 25도 이상인 열대야는 평년대비 최근 10년간 연간발생일수가 1.3일 증가하였으나 일최고기온 $35^{\circ}C$ 이상인 날의 수는 오히려 감소하는 경향을 보인다. 이것은 여름철 강수량이 증가하고, 호우발생빈도, 특히 8월의 강수일수가 증가하고 있다는 것과 밀접한 관련이 있다. 여름과 가을에 우리나라에 영향을 미치는 태풍의 수는 뚜렷한 추세를 보이지 않으나, 2002년 루사, 2003년 매미로 인하여 각각 6조원, 4조원 이상의 막대한 피해가 발생하였다. 태풍에 의한 피해액은 GDP 대비 약 0.9%(태풍 루사)로 최근 경제상장률과 비교해 보면, 상당한 비율을 차지한다. 우리나라에 영향을 미치는 태풍은 연근해의 해수면 온도가 높아지면 세기가 강해질 가능성이 높다. 폭설과 한파일수도 평년대비 최근 10년 감소하였고 일최저기온이 영하 $10^{\circ}C$ 이하인 날도 연간 발생일수가 감소하였다. 최근 10년간 우리나라 기후의 변화특성은 기온상승과 더불어 서리종료일이 앞당겨지고 열대야가 증가하고 폭설, 한파, 겨울철 일최저기온 영하 10도 이하인 날의 감소 등이 나타나고, 여름철 재해의 원인인 호우일수는 증가하는 추세이다. 앞으로 지구온난화는 가속화될 것으로 전망되고 이로 인한 피해규모도 커질 것으로 예상된다. 최근 우리나라에서 나타나는 기후변화의 추이를 감안할 때, 기후변화에 대한 장기적인 대비책을 마련하여 이로 인한 부정적인 영향을 감소시키기 위하여 국가차원의 체계적인 대응이 필요하다.

• Molecules and Cells
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• v.26 no.2
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• pp.181-185
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• 2008

The effects of calcitonin gene-related peptide (CGRP) on pacemaker currents in cultured interstitial cells of Cajal (ICC) from the mouse small intestine were investigated using the whole-cell patch clamp technique at $30^{\circ}C$. Under voltage clamping at a holding potential of -70 mV, CGRP decreased the amplitude and frequency of pacemaker currents and activated outward resting currents. These effects were blocked by intracellular $GDP{\beta}S$, a G-protein inhibitor and glibenclamide, a specific ATP-sensitive $K^+$ channels blocker. During current clamping, CGRP hyperpolarized the membrane and this effect was antagonized by glibenclamide. Pretreatment with SQ-22536 (an adenylate cyclase inhibitor) or naproxen (a cyclooxygenase inhibitor) did not block the CGRP-induced effects, whereas pretreatment with ODQ (a guanylate cyclase inhibitor) or L-NAME (an inhibitor of nitric oxide synthase) did. In conclusion, CGRP inhibits pacemaker currents in ICC by generating nitric oxide via G-protein activation and so activating ATP-sensitive $K^+$ channels. Nitric oxide- and guanylate cyclase-dependent pathways are involved in these effects.

• International Commerce and Information Review
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• v.16 no.4
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• pp.385-408
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• 2014

The purpose of this paper is to find the determinants of Korean FDI(1996~2012) in China using the spatial autoregressive model and four regions of China is analyzed respectively. Most previous studies ignored spatial interdependence to analyze the determinants of Korean outward FDI in China. Empirical results of total Chinese area shows per RGDP and spatial effects are positive and significant variables. Results of region A reveal that per RGDP is positive and spatial effects are negative and significant. Results of region B shows that both per GDP and spatial effects are positive. All variables of region C are insignificant but those of region D are significant and positive. This means that Korean companies to invest in region D should consider spatial characteristics of surrounding areas of D.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.1
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• pp.25-30
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• 2008

Although many studies show that thromboxane $A_2\;(TXA_2)$ has the action of gastrointestinal (GI) motility using GI muscle cells and tissue, there are no reports on the effects of $TXA_2$ on interstitial cells of Cajal (ICC) that function as pacemaker cells in GI tract. So, we studied the modulation of pacemaker activities by $TXA_2$ in ICC with whole cell patch-clamp technique. Externally applied $TXA_2\;(5{\mu}M)$ produced membrane depolarization in current-clamp mode and increased tonic inward pacemaker currents in voltage-clamp mode. The tonic inward currents by $TXA_2$ were inhibited by intracellular application of GDP-${\beta}$-S. The pretreatment of ICC with $Ca^{2+}$ free solution and thapsigargin, a $Ca^{2+}$-ATPase inhibitor in endoplasmic reticulum, abolished the generation of pacemaker currents and suppressed the $TXA_2$-induced tonic inward currents. However, chelerythrine or calphostin C, protein kinase C inhibitors, did not block the $TXA_2$-induced effects on pacemaker currents. These results suggest that $TXA_2$ can regulate intestinal motility through the modulation of ICC pacemaker activities. This modulation of pacemaker activities by $TXA_2$ may occur by the activation of G protein and PKC independent pathway via extra and intracellular $Ca^{2+}$ modulation.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.176-183
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• 2012

Eukaryotic translation termination is governed by eRF1 and eRF3. eRF1 recognizes the stop codons and then hydrolyzes peptidyl-tRNA. eRF3, which facilitates the termination process, belongs to the GTPase superfamily. In this study, the effect of the MC domain of eRF1a (eRF1aMC) on the GTPase activity of eRF3 was analyzed using fluorescence spectra and high-performance liquid chromatography. The results indicated eRF1aMC promotes the GTPase activity of eRF3, which is similar to the role of eRF1a. Furthermore, the increased affinity of eRF3 for GTP induced by eRF1aMC was dependent on the concentration of $Mg^{2+}$. Changes in the secondary structure of eRF3C after binding GTP/GDP were detected by CD spectroscopy. The results revealed changes of conformation during formation of the eRF3C GTP complex that were detected in the presence of eRF1a or eRF1aMC. The conformations of the eRF3C eRF1a GTP and eRF3C eRF1aMC GTP complexes were further altered upon the addition of $Mg^{2+}$. By contrast, there was no change in the conformation of GTP bound to free eRF3C or the eRF3C eRF1aN complex. These results suggest that alterations in the conformation of GTP bound to eRF3 is dependent on eRF1a and $Mg^{2+}$, whereas the MC domain of eRF1a is responsible for the change in the conformation of GTP bound to eRF3 in Euplotes octocarinatus.