• Molecules and Cells
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• 제23권2호
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• pp.252-257
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• 2007

Escherichia coli HslVU is an ATP-dependent protease consisting of two heat shock proteins, the HslU ATPase and HslV peptidase. In the reconstituted enzyme, HslU stimulates the proteolytic activity of HslV by one to two orders of magnitude, while HslV increases the rate of ATP hydrolysis by HslU several-fold. Here we show that HslV alone can efficiently degrade certain unfolded proteins, such as unfolded lactalbumin and lysozyme prepared by complete reduction of disulfide bonds, but not their native forms. Furthermore, HslV alone cleaved a lactalbumin fragment sandwiched by two thioredoxin molecules, indicating that it can hydrolyze the internal peptide bonds of lactalbumin. Surprisingly, ATP inhibited the degradation of unfolded proteins by HslV. This inhibitory effect of ATP was markedly diminished by substitution of the Arg86 residue located in the apical pore of HslV with Gly, suggesting that interaction of ATP with the Arg residue blocks access of unfolded proteins to the proteolytic chamber of HslV. These results suggest that uncomplexed HslV is inactive under normal conditions, but may can degrade unfolded proteins when the ATP level is low, as it is during carbon starvation.

• Animal Bioscience
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• 제36권10호
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• pp.1604-1611
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• 2023

Objective: The aim of this study was to investigate the protective effect of wheat phytase as a structural decomposer of inflammatory nucleotides, extracellular adenosine triphosphate (ATP), and uridine diphosphate (UDP) on HT-29 cells. Methods: Phosphatase activities of wheat phytase against ATP and UDP was investigated in the presence or absence of inhibitors such as L-phenylalanine and L-homoarginine using a Pi Color Lock gold phosphate detection kit. Viability of HT-29 cells exposed to intact- or dephosphorylated-nucleotides was analyzed with an EZ-CYTOX kit. Secretion levels of pro-inflammatory cytokines (IL-6 and IL-8) in HT-29 cells exposed to substrate treated with or without wheat phytase were measured with enzyme-linked immunosorbent assay kits. Activation of caspase-3 in HT-29 cells treated with intact ATP or dephosphorylated-ATP was investigated using a colorimetric assay kit. Results: Wheat phytase dephosphorylated both nucleotides, ATP and UDP, in a dose-dependent manner. Regardless of the presence or absence of enzyme inhibitors (L-phenylalanine and L-homoarginine), wheat phytase dephosphorylated UDP. Only L-phenylalanine inhibited the dephosphorylation of ATP by wheat phytase. However, the level of inhibition was less than 10%. Wheat phytase significantly enhanced the viability of HT-29 cells against ATP- and UDP-induced cytotoxicity. Interleukin (IL)-8 released from HT-29 cells with nucleotides dephosphorylated by wheat phytase was higher than that released from HT-29 cells with intact nucleotides. Moreover, the release of IL-6 was strongly induced from HT-29 cells with UDP dephosphorylated by wheat phytase. HT-29 cells with ATP degraded by wheat phytase showed significantly (13%) lower activity of caspase-3 than HT-29 cells with intact ATP. Conclusion: Wheat phytase can be a candidate for veterinary medicine to prevent cell death in animals. In this context, wheat phytase beyond its nutritional aspects might be a novel and promising tool for promoting growth and function of intestinal epithelial cells under luminal ATP and UDP surge in the gut.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.299.2-300
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• 2001

• The Korean Journal of Physiology and Pharmacology
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• 제8권2호
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• pp.95-100
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• 2004

Ischemic preconditioning (IPC) has been accepted as a heart protection phenomenon against ischemia and reperfusion (I/R) injury. The activation of ATP-sensitive potassium $(K_{ATP})$ channels and the release of myocardial nitric oxide (NO) induced by IPC were demonstrated as the triggers or mediators of IPC. A common action mechanism of NO is a direct or indirect increase in tissue cGMP content. Furthermore, cGMP has also been shown to contribute cardiac protective effect to reduce heart I/R-induced infarction. The present investigation tested the hypothesis that $K_{ATP}$ channels attenuate DNA strand breaks and oxidative damage in an in vitro model of I/R utilizing rat ventricular myocytes. We estimated DNA strand breaks and oxidative damage by mean of single cell gel electrophoresis with endonuclease III cutting sites (comet assay). In the I/R model, the level of DNA damage increased massively. Preconditioning with a single 5-min anoxia, diazoxide $(100\;{\mu}M)$, SNAP $(300\;{\mu}M)$ and 8-(4-Chlorophenylthio)-guanosine-3',5'-cyclic monophosphate (8-pCPT-cGMP) $(100\;{\mu}M)$ followed by 15 min reoxygenation reduced DNA damage level against subsequent 30 min anoxia and 60 min reoxygenation. These protective effects were blocked by the concomitant presence of glibenclamide $(50\;{\mu}M)$, 5-hydroxydecanoate (5-HD) $(100\;{\mu}M)$ and 8-(4-Chlorophenylthio)-guanosine-3',5'-cyclic monophosphate, Rp-isomer (Rp-8-pCPT-cGMP) $(100\;{\mu}M)$. These results suggest that NO-cGMP-protein kinase G (PKG) pathway contributes to cardioprotective effect of $K_{ATP}$ channels in rat ventricular myocytes.

• 한국전자통신학회논문지
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• 제8권12호
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• pp.1905-1910
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• 2013

논문은 유도 루프식 열차제어시스템에 대하여 준 정량적 안전무결성 등급(Safety Integrity Level : SIL)할당 방법을 적용하여 안전무결성 등급을 할당한 결과이다. 유도 루프식 열차제어시스템은 ATS장치, 지상ATP장치, 차상ATP장치, 지상ATO장치, 차상ATO 지상장치 하드웨어 및 소프트웨어로 구성되어 있으며, 안전무결성 등급 할당은 각 서브시스템에 대한 안전무결성 등급을 의미한다. 준 정량적 방법의 세 원칙에 근거하여, 열차제어시스템을 구성하고 있는 서브시스템에 대한 안전무결성 등급을 할당하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.666-670
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• 2011

ATS(Automatic Train Stop)s are is effected by track environment, signal distance and train braking distance. So onboard signaling systems such as ATP(Automatic Train Protection) are installed on conventional lines by some train operation companies. With the mixed signalling, the onboard signaling system is overlaid on a conventional line with ATS, it is possible to run the line with conventional trains and ATP trains and to use the advantages of ATP(higher speed or more trains on the line). This paper includes guidelines a mixed signalling(ETCS and ATS) system architecture, operation concepts and infill balise installation.

• 약학회지
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• 제33권3호
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• pp.149-155
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• 1989

To predict the influence of carbon monoxide poisonining on cerebral energy metabolism, rats were exposed to 5000 ppm environment for 30 minutes. Carboxyhemoglobin (HBCO) saturation rate in this condition was 72% equally in male and female rats. Cerebral cortex in the rats showed lower level of ATP, glucose, creatine phosphate and higher level of lactate, pyruvate by anaerobic glycolysis. As for the levels of ATP, creatine phsphate and glucose, the cerebral cortex contents of them were larger in female rats of estrus than in male rats, whereas there was no difference between sexes in the levels of pyruvate and lactate. According to time passage from CO intoxication, the mode of changes in cerebral energy metabolite contents was similar in both sexes.

• 한국식품조리과학회지
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• 제16권2호
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• pp.195-201
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• 2000

대학 급식 시설의 미생물적 위생상태를 평가하기 위해서 도마, 칼, 식판 그리고 행주에 대하여 ATP bioluminescence와 표준평판 균수를 측정 비교하여 분석, 평가한 결과는 다음과 같다. 1) 도마, 칼, 식판 그리고 행주에 대한 표준평판 균수의 허용기준으로 1 $\textrm{cm}^2$당 40을 기준으로 하고 ATP bioluminescence는 800 RLU을 허용기준으로 하여 만족 할만한 수준과 시정할 수준으로 구분하여 위생상태를 평가하였을 때 ATP bioluminescence 측정값과 표준평판 균수 측정값은 84.7%의 일치도를 보였다. 2) 사용 전 도마, 칼, 식판, 및 행주의 ATP bioluminescence 측정값과 표준평판 균수 측정값의 일치도는 91.7%, 사용 중 두 값의 일치도는 75%. 그리고 세척ㆍ소독 후의 두값의 일치도는 87.5%로 사용 전의 일치도가 가장 높았고 사용 중의 일치도가 가장 낮았다. 3) ATP bioluminescence 측정과 표준 평판 균수 측정으로 얻어진 결과에서 사용 전 도마, 칼, 식판, 및 행주의 87.5%가 허용기준 이하이고, 사용 중 도마, 칼, 식판, 및 행주의 29.2%만이 허용기준 이하이며, 세척ㆍ소독 후 도마, 칼, 식판, 및 행주의 42.7%가 허용기준 이하로 사용전의 위생상태가 가장 양호하며 사용 중인 경우 위생상태가 가장 불량하여 즉각적인 조치가 필요하다. 4) 사용 전 도마, 칼, 식판, 행주 4종류의 표준평판 균수가 허용기준 이하 검출된 대학 급식 시설은 3곳이며, 사용 중 4종류의 표준평판 균수가 허용기준 이하 검출된 곳은 없었고 세척ㆍ소독 후 4종류의 표준평판 균수가 허용기준 이하 검출된 곳도 없었다. 5) 도마, 칼, 식판, 및 행주의 용도별 분리사용은 거의 이루어지고 있지 않고 있다. 특히 칼과 도마는 교차오염의 가능성이 크므로 용도에 따라 구분하여 분리 사용이 필요하며 소독방법 및 횟수에서 행주의 소독이 가장 잘 이루어지고 있으며 도마의 소독이 가장 미흡하게 나타나고 있다. 사용 중 도마, 칼, 행주에 대한 즉각적인 조치와 분리 사용이 필요하며 칼, 도마, 행주에 대한 적절한 소독 방법이 강구되어야 한다고 사려된다. 결론적으로 ATP bioluminescence 측정값은 표준평판균수 측정값과 높은 일치도를 보여 급식 분야의 미생물 품질관리 평가에 ATP bioluminescence 측정의 이용 가능성이 높게 나타나고 있으며 실제로 HACCP system에 적용하기 위하여 보다 지속적인 연구가 필요하다고 사려된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.251-254
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• 2011

This paper describes the design and implementation of the DMI display based on ERTMS specification for the Integrated Onboard Signaling System (IOSS). IOSS is consists of ATS, ATC, and ATP based on ERTMS/ETCS Level 1. We propose an improved DMI display design which has single layout concept for the IOSS. When a train is in the ATS, ATC, or ATP railway section, it is protected by the ATS, ATC, or ATP equipment, respectively. Therefore, DMI should display the different information according to the each signaling system. We design DMI display implemented as single layout for ATP, ATS and ATC information. This single layout display has a well integrated look and feel using the ERTMS specification and layout. This is for the driver to perceive the information easily and not to experience inconvenience resulting from the sense of difference when the train crossed into the different signaling section. Finally, we show the implementation result following this concept.

• 한국환경보건학회지
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• 제27권2호
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• pp.82-91
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• 2001

This study was carried out to elucidate the protective effect of zinc chloride(ZnCl$_2$) and its mechanism against the immuno-cytotoxicity of methylmercury chloide($CH_3$HgCl). This study was observed in the culture of EMT-6 cells which are originated from mammary adenocarcinoma of Balb/c mouse. Cytotoxicity of metals was measured by cell viability and NO$_2$$^{[-10]}$ , and mitochondrial function was evaluated by adenosine triphosohate (ATP) production. $CH_3$HgCl significantly decreased the sythesis of nitric oxide(NO), ATP and glutathione(GSH) in a dose-dependent manner. ZnCl$_2$ significantly increased the synthesis of GSH in a dose-dependent manner, but synthesis of NO and ATP were not changed. The immuno-cytotoxicity of $CH_3$HgCl was not fully protected when combined addition of ZnCl$_2$, whereas ZnCl$_2$ prior to addition of $CH_3$HgCl completly protected the Hg-induced immuno-cytotoxicity. Similarly, intracellular accumulation of mercury significantly decreased by ZnCl$_2$. Degree of diminution of intracellular mercury was larger in ZnCl$_2$ prior to addition of $CH_3$HgCl than in combined addition of ZnCl$_2$ and $CH_3$HgCl.. Dithiothreitol(DTT) or buthionine sulfoximine(BSO) addition at 50$\mu$M or less, which was not toxic to the cells, did not affect synthesis of NO and ATP. DTT increased intracellular GSH level and DTT pretreatment protected toxicity induced by $CH_3$HgCl as shown complete recover in the NO and ATP values. BSO decreased intracellular GSH level and BSO pretreatment exaggerated toxicity induced by $CH_3$HgCl as shown synergistic reduction in the NO and ATP values. These results indicated that the protective effects of zinc against immuno-cytotoxicity of methylmercury associated with increasing cellular level of GSH. Increased intracellular GSH transports methylmercury to out of cells. In accordance with intracellular level of mercury decreased, immuno-cytotoxicity of methylmercury decreased. These result also suggest that the protective mechanism of zinc against the mercury toxicity would be exerted in the immune system in vivo.