• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.154-159
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• 1999

EDTA (ethylenediaminetetraacetic acid), a chelating agent is most widely used in industrial applications, especially for cleaning of metals in water, frequently prohibits metal removal from water in conventional water treatment technologies. It could be easier to remove aqueous metal ions by the breakdown of DETA complexed bonds first. This study investigated the availability of $TiO_2$ photo-catalysis for the aqueous phase oxidation of Cu(II)-EDTA, under an aerobic condition at $20^{\circ}C$ with $TiO_2$ (Degussa P-25) and 1.79mM of Cu(II)-EDTA. When $TiO_2$ loading was 2.0 g/L, the photo-catalytic oxidation of Cu(II)-EDTA was maximal. The tendency of EDTA adsorption onto the catalyst surface was affected by $TiO_2$ surface charge, and the oxidation rate of Cu(II)-EDTA by photo-catalysis was shown to be dependent upon the tendency of EDTA adsorption before photo-irradiation.

• Journal of Life Science
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• v.9 no.2
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• pp.169-175
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• 1999

Salmonella typhimurium can encounter a wide variety of environments during its life cycle. In nature, S. typhimurium can experience and survive dramatic acid stresses that occur in diverse ecological niches ranging from pond water to phagolysosomes. These survival mechanism is aquired by the Acid Tolerance Response(ATR) in Salmonella. The ATR of S. typhimurium is a complex inducible phenomenon in which exposures to slight or moderate low pH will produce a stress response capable of protecting the organism against more severe acid challenges. ATR in Salmonella has two different systems that are called RpoS dependent and independent. We found that ATR in anaerobic was showed RpoS independent because rpoS$\Omega$AP had ATR as S. typhimurium UK1. Using the P22 MudJ(Km, lacZ) operon fusion technique and a lethal selection procedure combining low pH(pH4.5) and sodium acetate(10mM, pH4.5), we isolated LF487 aatA::MudJ which showed acid sensitive in anaerobic condition. aatA locus was determined at 12 min on Salmonella Genetic Map. The survival rate of aatA mutant was showed significantly diminished at pH4.3 than virulent wild type Salmonella in anaerobic condition(5% $CO_2$, 5% H$_2$, 90% $N_2$). Therefore isolated gene was confirmed important gene for anaerobic ATR system.

• Journal of Life Science
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• v.22 no.6
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• pp.807-814
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• 2012

Saururus chinensis has long been widely used in oriental folk medicines to treat diseases. In the current study, organic solvent fractions obtained from the main methanolic extract of S chinensis were evaluated for their antioxidative and related physiological activities. The antioxidant activity of the fractions was measured using DPPH free radical scavenging activity, increased in a dose-dependent manner, and the $ED_{50}$ of the ethyl acetate fractions exhibited a value of 12.84 ${\mu}g/ml$ higher than 27.22 ${\mu}g/ml$ compared to the BHT. Also, the cell viability of S. chinensis on $H_2O_2$-induced HDF cell death ($IC_{50}$) showed the highest cell viability of 89.39% in 50 ${\mu}g/ml$ of ethyl acetate fraction and 67.98% of visible cell survival rate in n-butanolic fraction. Meanwhile, all fractions of the S. chinensis extract led to a slight down regulation of the mRNA expression of fibulin-5, which is related to skin elasticity, and the ethyl acetate fraction having high antioxidant activity showed a markedly inhibitory effect on chick embryonic angiogenesis using the CAM assay. These results suggest that the ethyl acetate fraction of S. chinensis extract could be a good material in therapeutic application for antioxidant and related anti-angiogenesis activities.

• Journal of Life Science
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• v.18 no.10
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• pp.1415-1419
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• 2008

This study was carried out to determine the inhibitory effects of methanol extracts from Korean Orysa sartiva and Coix lachryma-jobi var. ma-yuen on mutagenicity using Ames test and growth of AGS human gastric adenocarcinoma and HT-29 human colon cancer cells. Both treatments of methanol extracts (5 mg/assay) from Orysa sartiva and Coix lachryma-jobi var. ma-yuen to Ames test system inhibited aflatoxin $B_1$ ($AFB_1$) induced mutagenicity by 76%. In case of N-methyl-N'-nitro-N-nitrosoguamidine (MNNG) induced mutagenicity, the methanol extracts (5 mg/assay) from Orysa sartiva and Coix lachryma-jobi var. ma-yuen showed 79% and 69% inhibitory rate, respectively and the inhibitory effect was a little stronger in Orysa sartiva Inhibitory effects of methanol extracts from Orysa sartiva. and Coix lachryma-jobi var. ma-yuen on the growth of AGS and HT-29 human cancer cells were increased as dose dependent patterns and the inhibitory effects on AGS and HT-29 cells were similar. The above results indicate that the consumption of these cereals, which contain many nutrients with good quality, may be recommended as potent functional foods for improving health.

• Journal of Life Science
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• v.24 no.5
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• pp.498-504
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• 2014

Mammalian hyaluronidases (HAase, EC 3.2.1.35) are a family of enzymes that hydrolyse N-acetyl-D-glucosamine (1-4) glycosidic bonds in hyaluronic acid, which is found in skin, cartilage, and the vitreous body. Although HAase is generally present in an inactive form within subcellular lysosomes, it is released in an active form in some types of inflammation and tissue injuries, thereby contributing to the inflammatory response. The HAase inhibitory activity of 500 methanolic extracts of 500 species from medicinal plants was screened using a Morgan microplate assay. The viscosity of the hyaluronic acid was measured with an Ubbelohde viscometer. Three MeOH extracts inhibited more than 50% of HAase activity at a concentration of 2 mg/ml. HAase inhibitory rates (%) of three species of medicinal plant extracts, Styrax japonica, Deutzia coreana, and Osmanthus insularis were 57.28%, 53.50%, and 53.19%, respectively. The rate of HAase inhibition of the extracts was dose dependent. In the HAase inhibitory assay using the Ubbelohde viscometer, the results were in good agreement with the results from the Morgan assay. The results suggest that HAase inhibitory compounds extracted from the stem of S. japonica, D. coreana, and O. insularis might be multifunctional and prevent the degradation of hyaluronic acid and the induction of allergic reactions and inflammation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1179-1185
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• 2004

The Korean traditional medicine, Seonghyangjeonggisan (SHJGS) has long been used for acute cerebral infarction (Cl). However, scientific investigation has been carried out a little. Cytokines, involved in the regulation of inflammatory reactions and immune responses, may play an important role in the pathogenesis of Cl. The aim of this study is to investigate the effects of SHJGS on the production of various cytokines in the patients with acute Cl. Peripheral blood mononuclear cells (PBMC) obtained from the patients with acute Cl were cultured for 24hr in the presence or absence of lipopolysaccharide (LPS) and phytohaemagglutinin (PHA). The amount of TNF-α, IL-1β, IL-6 and IL-8, in PBMC culture supernatant, was significantly increased in the LPS and PHA treated cells, compared with unstimulated cells (P<0.05). This study showed that increased TNF-α, IL-1β, IL-6 and IL-8 level stimulated by LPS and PHA was inhibited by SHJGS (0.01-1 ㎎/㎖) in a dose-dependent manner but IL-8 level was not inhibited significantly at 1㎎/㎖ (P>0.05). The maximal inhibition rate of TNF-α, IL-1β, IL-6 and IL-8 by SHJGS (1㎎/㎖) was 68% (P<0.05), 53.9% (P<0.05), 45.5% (P<0.05), 46.7% (P>0.05) respectively. These results suggest that SHJGS might have anti-inflammatory effects through cytokine modulation. which might explain its beneficial effects in the treatment of acute Cl.

• Parasites, Hosts and Diseases
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• v.28 no.2
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• pp.71-78
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• 1990

To assess the role of cAMP on the growth and proliferation of Toxoplasma in HL-60 cells we tested the effect of exogenous cAMP and cAMP analogues to the co-culture system of Toxoplasma and HL-60 cells. cAMP, dbcAMP, and br-cAMP stimulated the growth of Texoplasma at a specific concentration, i.e., 100 mM, l00 mM, and 10-1 mM, respectively. There were differences in growth induction kinetics and in the rate of promotion. These results were further verified by treating the co-culture with adenylate cyclase activator, pNHppG, cAMP phosphodiesterase activators, imidasole and A23187, and cAMP phosphodiesterase inhibitors, IBMX, compound 48/80, and theophylline, separately. When the cytosolic cAMP levels increased by the reagents mentioned above, Toxoplasma in the cytoplasm of HL-60 cells stimulated to proliferate more rapidly with concentration-dependent modes compared to the control, and vice versa. It is suggested that some mechanisms are activated by the high levels of cAMP in the cytoplasm, which result in the stimulation of Toxoplasma proliferation.

• The Journal of Korean Society for School & Community Health Education
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• v.20 no.3
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• pp.67-82
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• 2019

Objectives: The purpose of this study is to analyze how the different lifestyles between Koreans and Korean Americans have significant effects on their health. Despite being the same race, Koreans and Korean Americans have different health conditions and health attitudes due to the acquired environmental factors such as social-economic factors, lifestyle risk factors, healthcare systems, and medical utilization. It is crucial to examine how the different lifestyle habits between Koreans and Korean Americans lead to various health conditions for establishing an effective health promotion policy. Methods: In this study, a comparative analysis was conducted using the National Health and Nutrition Survey of Korea and CHIS data of the United States in 2005 and 2015 to provide valuable insights when establishing such a policy. Results: The specific research purpose is as follows: First, socioeconomic factors, such as (1)living habits risk factors, (2)health satisfaction levels, (3)disease outbreaks, and (4)medical uses, are analyzed to find the distinct characteristics among Koreans, Korean Americans, and Americans. Second, the three groups --Koreans, Korean Americans, and Americans-- were compared based on their exposure to disease-related lifestyle risk factors related to their body mass index and their general health condition. The research results are as follows: First, all three groups improved health conditions in 2015 better than in 2005. Koreans maintained relatively higher general health conditions compared to other groups: their prevalence rate of chronic diseases such as diabetes, high blood pressure, heart disease, and asthma was lower than that of U.S. residents. Second, in regards to health behavior factors, the lifetime smoking experience for Koreans and Americans both decreased in 2015 compared to 2005, while the lifetime smoking experience for Korean Americans increased slightly. The number of smokers for Koreans has greatly decreased over a decade while that of Americans has moderately increased. Third, according to the results of the multiple regression, the general health conditions, which is a dependent variable, suggests that the number of men who answered they are healthy is greater than that of women in Korea, compared to the United States. Conclusions: In conclusion, the acquired environmental factors had more significant impacts on health than the racial factors did. Compared to 2005, the health behaviors and health levels of Korean Americans in 2015 gradually became more similar to those of Americans.

• Journal of Intelligence and Information Systems
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• v.9 no.1
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• pp.227-249
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• 2003

Prediction of corporate failure using past financial data is a well-documented topic. Early studies of bankruptcy prediction used statistical techniques such as multiple discriminant analysis, logit and probit. Recently, however, numerous studies have demonstrated that artificial intelligence such as neural networks can be an alternative methodology for classification problems to which traditional statistical methods have long been applied. In building neural network model, the selection of independent and dependent variables should be approached with great care and should be treated as model construction process. Irrespective of the efficiency of a teaming procedure in terms of convergence, generalization and stability, the ultimate performance of the estimator will depend on the relevance of the selected input variables and the quality of the data used. Approaches developed in statistical methods such as correlation analysis and stepwise selection method are often very useful. These methods, however, may not be the optimal ones for the development of neural network model. In this paper, we propose a genetic algorithms approach to find an optimal or near optimal input variables fur neural network modeling. The proposed approach is demonstrated by applications to bankruptcy prediction modeling. Our experimental results show that this approach increases overall classification accuracy rate significantly.

• The Journal of Korean Medicine
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• v.20 no.2
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• pp.108-120
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• 1999

In this study, body weight levels of glucose, insulin and triglyceride in blood and glucosidase activity of the small intestine were investigated to determine the effect of Sangbaegpitang and Supungsungiwhan on the glucose metabolism of db/db mice. The GLUT4 mRNA of muscle tissue and the Acetyl CoA Carboxylase and the activation rate of GLUT2 mRNA of liver tissue were measured by the reverse transcription-polymerase chain reaction method and by the vitro transcription. The results were obtained as follows: 1. In the Sangbaegpitang administration group, (1) The level of triglyceride was decreased significantly and the glucosidase activity of the small intestine was inhibited remarkably, (2) The amounts of the GLUT4 mRNA in muscle tissue and Acetyl CoA Carboxylase mRNA in liver tissue were increased significantly. (3) Though glucose level in both fasting and non-fasting, were decreased and the insulin level in blood was increased, the results showed no statistical significance. 2. In the Supungsungiwhan administration group, (1) The levels of glucose and triglyceride were decreased significantly in the blood of non-fasting animals. (2) The glucosidase activity of small intestine was inhibited markedly and the amounts of GLUT4 mRNA of muscle tissue and GLUT2 mRNA of liver tissue were increased significantly. (3) The glucose levels in the fasting group were reduced, while insulin level was increased but showed no statistical significance, Based on the above results, our conclusions are as follows: Sangbaegpitang & Supungsungiwhan are thought to be capable of inhibiting the activity glucosidase, the enzyme which influences carbohydrate metabolism in the small intestine of db/db mice(the experimental diabetic model) and delaying the absorption of carbohydrate, thus proving effective on inhibiting the increase of non-fasting glucose level effectively. Futhermore Sangbaegpitang and Supungsungiwhan are though: to be capable of preventing the composition of free fatty acids by restoring the production of GLUT4 mRNA of muscle tissues and GLUT2 mRNA of liver tissues. Those results suggests that above prescriptions can be applied to non-insulin dependent diabetes mellitus in order to improve insulin resistance.