• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.4
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• pp.710-718
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• 2011

Edema factor(EF) is a portion of anthrax toxin which produces edema when combined with protective antigen. This paper describes about technique for cloning, expression, purification and activity test of EF. Using the E. coli expression system, we could make recombinant EF protein although it's origin is Bacillus anthracis. And also we could culture massively and purify highly pure protein. Finally we confirm a enzyme activity of purified EF to increase intracellular cAMP level. Through establishing this technique, it can be possible to research about EF in depth and apply to expression and purification of many other protein in biology.

• The Journal of Internal Korean Medicine
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• v.33 no.3
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• pp.272-283
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• 2012

Objectives : The purpose of this study was to investigate the mechanism of protective effect of Jinmu-tang (JMT, Zhenwu-tang) extract on $H_2O_2$-induced cell death in C6 glial cells. Methods : Cultured C6 glial cells of white mice were pretreated with JMT extract and exposed to $H_2O_2$ for inducing cell death. We measure the cell viability by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and investigate the cell morphology using a light microscope after crystal violet (CV) staining. Reactive oxygen species (ROS) formation was analyzed using a flow cytometer and a fluorescent microscope after staining with 2'7'-dichlorofluorescein diacetate (DCF-DA). DNA fragmentation was analyzed using a flow cytometer after propidium iodide (PI) staining and nuclei morphology was investigated using a fluorescent microscope after 2-[4-amidinophenyl]-6-indo-lecarbamidine dihydrochloride (DAPI) staining. We analyzed expression of Bax, processing of procaspase-3 and poly (ADP-ribose) polymerase (PARP), and activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) by western blot method. Tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) secretion was analyzed using Quantikine kit. Results : We determined the elevated cell viability by JMT extract on $H_2O_2$-induced C6 glial cell death. ROS formation, DNA fragmentation, $I{\kappa}B{\alpha}$ phosphorylation, NF-${\kappa}B$ activation, and secretion of TNF-${\alpha}$ induced by $H_2O_2$ are inhibited by JMT extract pre-treatment. JMT extract inhibits Bax expression, processing of caspase-3 and PARP that are critical biochemical markers of apoptotic cell death. Conclusions : These results suggest that JMT extract has a protective effect on $H_2O_2$-induced C6 glial cell death in various pathways.

• Korean Journal of Social Welfare Studies
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• no.39
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• pp.315-342
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• 2008

The aim of this study was to examine growth trajectories of delinquent behaviors during adolescence. In addition, the effects of protective and risk factors that might account for individual difference in the level of delinquent behaviors and in the rate of change were examined. Four waves of data in the Korea Youth Panel Survey(KYPS) were used to analyze the linear growth modeling. The sample consisted of 3346 adolescents who were assessed at 4 measurement waves with approximately 1-year intervals. The results showed significant individual differences in both final level of delinquent behaviors and in the rate of change across 3 measurement occasions. Adolescent gender, family's socioeconomic background predicted the final level and the rate of change of delinquent behaviors. The protective effects of positive parenting and self-control were significantly associated with problem behaviors and the risk effects of the association with deviant peers and negative stigma were significant on the final level of delinquency. Self-control and deviant peer affiliation had differential influences over time significantly. Practice and policy implications as well as further research topic were discussed in the light of searching for important factors in preventing adolescent problem behaviors.

• The Korea Journal of Herbology
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• v.36 no.1
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• pp.59-66
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• 2021

Objectives : Forsythiae Fructus has been reported to have anti-inflammatory effects in many diseases, and Corydalis Tuber has been used as a pain suppressor in Eastern Asia. However, the protective effects of individual water extract of Forsythiae Fructus (FF) and Corydalis Tuber (CT) and the mixture of FF and CT (FC) on chronic pancreatitis (CP) were not well-investigated. Therefore, we investigated the protective effects of FF, CT, and FC on CP in mice. Methods : To induce CP, cerulein was injected 6 times a day, 4 times a week for 3 weeks. 1 h before the every cerulein injection, 200 mg/kg of FF, CT, or FC was intraperitoneally injected to mice. Histological analysis of pancreas was examined by hematoxylin and eosin stain and collagen deposition was examined by Masson's trichrome stain. Fibrogenic parameters such as α-smooth muscle actin (α-SMA), extracellular matrix (ECM) deposition, and fibrotic cytokines such as transforming growth factor (TGF)-β1 and platelet-derived growth factor (PDGF) were also analyzed by immunofluorescence stain and real-time PCR. Results : Histological damages in pancreas were inhibited by pre-treatment of FF or FC but not CT. α-SMA and ECM in pancreas were inhibited by pre-treatment of CT or FC but not FF. Moreover, the expression of TGF-β1 and PDGF in pancreas were inhibited by FF, CT or FC. Conclusions : Our results suggest that FC have protective effect on CP in mice through inhibition of α-SMA, ECM, TGF-β1 and PDGF in pancreas, and these findings could suggest new clinical strategy for CP.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.290-293
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• 2001

This paper presents the reach accuracy of a distance relay for protection of transmission line according to power system conditions. The apparent impedance of distance relay is considerably affected by source impedance, load current, power factor, fault point and resistance etc. For protective coordination on the variables power system parameters, trip characteristics of distance relay at sending and receiving terminal are discussed.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.66-67
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• 2003

It is well known that osteoblasts and osteoc1asts playa key role in bone metabolism. They involve in osteoformation or bone destruction which are ragulated by various factors such as thyroid hormone, parathyroid hormone, estrogen, growth factor and cytokine. Recently, it is demonstrated that oxidative stress is one of pathological factors in bone metabolism, but it is left unknown about mechanism between oxidative stress and bone metabolism.(omitted)

• Journal of Powder Materials
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• v.11 no.3
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• pp.217-223
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• 2004

Submicron nickel powders were prepared from aqueous solution under hydrothermal condition. The experimental conditions including the types of protective agents, concentration of the solution and the pH were studied in detail. Starting concentration of nickel ion is a dominant factor affecting particle size. It was shown that the subsequent addition of Poly Vinyl Pyrrolidone(PVP) and Sodium Dodecyle Sulfate(SDS) can help to disperse the nickel powder. X-ray diffraction and SEM were employed to characterize the products.

• Korean Journal of Culture and Social Issue
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• v.12 no.5_spc
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• pp.99-116
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• 2006

This paper discuss adolescent's a quality of life related with risk behavior. The purpose of this study investigate to influence on risk behavior(runaway, smoking, sexual behavior) of the protective factors that moderate adolescent's problem behavior(delinquency). The assumption of this study that the protective factors counterbalance the negative influence of risk factors and finally, diminish a the problem behavior including a delinquent. A total of 1,020 students of a vocational high schook and a 216 adolescents of a special groups(the public institution that consisted with a delinquent young man) completed the questionnaires(risk behavior, 5 protective factors) of compiled by this researcher. The protective factors have selected based on the various prior studies analyzed with adolescent's risk behavior a family functioning, a father(a mother) each and child communication, a self efficacy, and a social support. Statistics appled for the data analysis are Chisqure analysis, two-way ANOVA, and Standard Discrimination analysis. The results of this study are as follows. First, the special group is higher than the general group in the rate of runaway, smoking, and sexual deviant behavior. Second, the protective factors are not action in the special group have experienced delinquency, but are only action in the general group consisted with the students of a vocational high schools. This means that the protective factors discriminating the participation of the risk behaviors, and blocking out the intervention of a problem behavior in the general adolescents. Although each protective factor influence to different according to each risk behavior, a role of a parent-child communication, a family functioning, and self-efficacy high orderly. Finally, discussed based on the previous studies that the protective factors moderate the negative influence of risk factors, offset the connection between a risk behavior and a. problem behavior, and improve and a resilience and the quality of life of the adolescents.

• BMB Reports
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• v.29 no.3
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• pp.200-204
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• 1996

Nerve growth factor (NGF) is literally known to promote neural differentiation and survival in several peripheral and central neurons. Thus, it is Widely believed that NGF may serve as a therapeutic agent for many types of neuronal diseases. One of the mechanisms suggested to explain the protective role of NGF is that the trophic factor can prevent the increase of intracellular calcium ions which might be responsible for neural death. To examine whether or not the calcium hypothesis works even under pathological conditions, we applied NGF to cultures deprived of glucose. Surprisingly, what was observed here is that NGF rather promoted cell death under a glucose-deprived condition. What we call the NGF paradox phenomenon occurred in a calcium concentration-dependent manner, indirectly suggesting that NGF might increase intracellular calcium ions in cells deprived of glucose. This suggestion is further supported by the fact that nifedipine, a well-known L-type calcium channel blocker, could block the cell death potentiated by NGF. Here it is still premature to propose the complete mechanism underlying the NGF paradox phenomenon. However, this study certainly indicates that NGF as a therapeutic agent for neuronal diseases should be carefully considered before use.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.195-198
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• 2006

Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.