• Herbal Formula Science
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• v.6 no.1
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• pp.215-226
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• 1998

Geagibokrounghwan (桂技茯笭湯) has long been used to cure human diseases such as vascular and blood disorders. However, it is still unkown on its action mechanism, physiolosical and biochemical meaning. Thus, many attempts were tried to show the scientific background covering the above mentioned mechanism. The effect of Geagibokrounghwan, which was known to date, as follow; effective circulation of body blood system, proliferation of leucocytes and antioxidative action. In this study, we have applied the Geagibokrounghwan administration and feed to mouse, to see effects on the expression of superoxide dismutase(SOD) mRNA as antioxidative agent and oxygen radical scavenger. Total RNAs includingmRNA have been isolated from liver and white blood cells after mice were fed with cholesterol in high dose. Also, in a separate group, the cholesterol-administrated mice were fed with Geagibokrounghwan to see the effects on SOD transcription. and then reverse transcriptase-polymerase chain reaction (RT-PCR) usion each primer set (SOD-F;GATGAAAGCGGTGT-3'; SOD-R; 5'-CCTGTGGAGTGATT-3') were performed to trace theamounts of mRNA. SOD mRNA was specifically expressed in Geagibokrounghwan-fed mice at 2 weeks after treatment, however, gradually reduced after 4 weeks. These results indicate that Geagibokrounghwan is highly applicable in treatment of the above mentioned human diseases.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.2
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• pp.11-22
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• 1996

It has been generally accepted that NOx formation increases as the maximum temperature or correspondingly the maximum pressure of a combustion system increases. Recently some exceptional experimental results have been reportes that under certain circumstance NOx formation could be reduced while the maximum pressure was increasing by varying the methods of combustion for the same kind of premixed gases. Until now that kind of results have been acquired only for the case of a dual opposed prechamber. But the mechanism has not been clearly understood yet. 3D computer simulation has been tried to clarify the mechanism. Flor this purpose KIVA-Ⅱ has been modified and applied to the model combustion chamber with which the same kind of experimental works have been done by the authors. A good agreement with the experimental results was achieved with the spatial and temporal resolution which is hard th be obtained by the experimental methods. And it was observed that for the dual opposed prechamber case the time for the NOx formation, which is non-equilibrium reaction, is shorter than any other case by an appropriate mixing process in the main combustion chamber. The shorter time reduceed heat loss through the combustion chamber walls and thereby obtaines the higher maximum pressure.

• Journal of dental hygiene science
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• v.17 no.5
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• pp.433-438
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• 2017

Relative to its incidence, oral cancer has serious negative social effects. The exact causes of oral cancer have not been clarified, but many studies have implicated smoking and drinking. However, the fundamental mechanism of oral cancer causation has yet to be elucidated. Lysophosphatidic acid (LPA) augments epithelial mesenchymal transition (EMT) and development of various cancer cells. However, a detailed mechanistic explanation for LPA-induced EMT and the effects of EMT-promoting conditions on oral squamous cell carcinoma development remain elusive. In the present study, a quantitative reverse transcription polymerase chain reaction was used to analyze TWIST1, Slug, E-cadherin, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) transcript expression. Immunoblotting was used to analyze TWIST1, Slug, E-cadherin, and GAPDH protein expression. siRNAs were used to silence TWIST1 and Slug transcript expression. A matrigel-coated in vitro invasion insert was used to analyze oral cancer cell invasion. The results of the present study show that the expression levels of TWIST1 and Slug, which are EMT factors, were increased by LPA treatment in YD-10B oral squamous cell carcinoma. Conversely, E-cadherin expression was significantly reduced. In addition, transfection of the cells with TWIST1 and Slug siRNA strongly inhibited LPA-induced oral cancer cell invasion. The present study shows that TWIST1 and Slug mediate LPA-induced oral cancer cell EMT and invasiveness. The present study confirmed the mechanism by which LPA promotes oral cancer cell development, with TWIST1 and Slug providing novel biomarkers and promising therapeutic targets for oral cancer cell development.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.251-258
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• 2005

In this study, a new concept for simulating a long-term mechanical degradation mechanism of shotcrete in tunnels has been proposed. In fact, it is known that the degradation takes place mainly by internal cracks and reduced stiffness, which results mainly from volume expansion of shotcrete and corrosion of cement materials, respectively. This degradation mechanism of shotcrete in tunnels appears similar to those of the most kinds of chemical reactions in tunnels. Therefore, the mechanical degradation induced by a kinds of chemical reaction was generalized and mathematically formulated in the framework of thermodynamics. The numerical model was implemented to a 3D finite element code, which can be used to simulate behaviour of shotcrete structures undergoing external forces as well as chemical degradation in time. A number of illustrative examples were given to show the feasibility of the model in tunnel designs with consideration of long-term degradation effect of shotcrete quantitatively for increase of long-term safety of tunnels.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.989-998
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• 2010

The titled dye of DBPI gives amplified spontaneous emission (ASE) with maximum at 580 nm upon pumping by nitrogen laser (${\lambda}_{ex}\;=\;337.1\;nm$). The ground state absorption cross section (${\sigma}_A$) and emission cross section (${\sigma}_E$) as well as effective emission cross section(${\sigma}^*_E$) have been determined. The electronic absorption spectra of DBPI were measured in ethanol and tetrahydrofuran at room and low temperature. DBPI displays molecular aggregation in water. The photochemical reactivity of DBPI was also studied in carbon tetrachloride upon irradiation with 525 nm light. The electrochemical investigation of DBPI dye has been carried out using cyclic voltammetry and convolution deconvolution voltammetry combined with digital simulation technique at a platinum electrode in 0.1 mol/L tetrabutyl ammonium perchlorate (TBAP) in two different solvents acetonitrile ($CH_3CN$) and dimethylformamide (DMF). The species were reduced via consumption of two sequential electrons to form radical anion and dianion (EE mechanism). In switching the potential to positive direction, the compound was oxidized by loss of two sequential electrons, which were followed by a fast dimerization and/or aggregation process i.e $EC_{dim1}EC_{dim2}$ mechanism. The electrode reaction pathway and the chemical and electrochemical parameters of the investigated compound were determined using cyclic and convolutive voltammetry. The extracted electrochemical parameters were verified and confirmed via digital simulation method.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.818-826
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• 1999

Antidiabetic activity and mechanism of Sangbackpitang (SBPT) was examined in db/db mice, which is a spontaneously hyperglycemic, hyperinsulinemic and obese animal model. SBPT and acarbose were administered orally for 4 weeks. Fasting and non-fasting serum glucose, glycated hemoglobin and triglyceride were all reduced when compared between db/db control group and SBPT treated group. At 12th week after birth, SBPT increased an insulin secretion although statistic significance was not seen. Total activities of sucrase, maltase and lactase in SBPT treated group were all decreased when compared to db/db control. On the other hand, sucrase and maltase activities in acarbose treated groups were increased. Effect of SBPT on mRNA expression of glucose transporter(GLUT-4) was also examined. Quantitation of glucose transporter was performed by RT-PCR and in vitro transcription with co-amplification of rat-action gene as an internal standard. Muscular GLUT-4 mRNA expression in SBPT treated group was increased significantly. These results may suggest that SBPT lowered blood glucose ascribing to inhibition of glycosidase-catalyzed reaction and upregulation of muscular GLUT-4 mRNA expression.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.6
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• pp.1525-1533
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• 2007

The discovery of drugs on the treatment of rhinitis and allergic disease is a very important subject in human heath. The Shinbijen has been used for centruries as a traditional medicine in Korea and is known to have an anti-inflammatory effect. However, its specific mechanism of action is still unknown. In this report, we investigated the effect of hot water extract from Shinbijen on OVA-mediated allergic reaction and studied its possible mechanism of action using fluorescenc microscopy and RT-PCR analysis. Shinbijen inhibited OVA-induced rhinitis, total cells in BFA and lymphocyte related to inflammation in mice. Shinbijen decreased immuno response, which activated by IL-4, COX-2 and iNOS expression. in tissue. Shinbijen reduced inflammatory molecule release from mice lung tissue and CD4/CD8 cells activated by cardiac blood. Shinbijen decreased OVA-induced IL-4 and iNOS levels in pulmonary alveoli. Our findings provide evidence that Shinbijen inhibits OVA-induced allergic reactions, and also demonstrate the involvement of inflammation and allergic disease in these effects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.5
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• pp.1260-1270
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• 2007

The discovery of drugs on the treatment of mast cell-mediated allergic disease is a very important subject in human heath. The Socheongyoug-tang(SCYT) has been used for centruries as a traditional medicine in Korea and is known to have an anti-inflammatory effect. However, its specific mechanism of action is still unknown. In this report, we investigated the effect of hot water extract from SCYT on RBL-2H3 mast cell-mediated allergic reaction and studied its possible mechanism of action. SCYT inhibited compound 48/80-induced systemic anaphylaxis and serum histamine release in mice. SCYT decreased the passive cutaneous anaphylaxis reaction activated by Anti-lgE antibody-HSA. SCYT dose-dependently reduced histamine release from mice peritoneal mast cells activated by Anti-lgE antibody-HSA. SCYT increased cAMP and decreased compound 48/80-induced intracellular $Ca^{2+}$ levels. Our findings provide evidence that SCYT inhibits mast-derived allergic reactions, and also demonstrate the involvement of cAMP and intracellular $Ca^{2+}$ in these effects.

• Journal of Soil and Groundwater Environment
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• v.20 no.5
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• pp.1-10
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• 2015

FeS, as a natural reduced iron mineral, has been recognized to be a viable reactive material for As(III) sequestration in natural and engineered systems. In this study, FeS-coated sand packed columns were tested to evaluate the As(III) removal capacities under anaerobic conditions at pH 5, 7 and 9. The column obtained As(III) removal capacity was then compared with the capacity result obtained from batch reactors. In the comparison, two different approaches were used. The first approach was used the total As(III) removal capacity which method was proved to be useful for interpreting pH 5 system. The second approach was used to consider sorption non-linearity and proved to be useful for interpreting the pH 9. The results demonstrated that a mechanistic understanding of the different removal processes at different pH conditions is important to interpret the column experimental results. At pH 5, where the precipitation of arsenic sulfide plays the major role in the removal of arsenic, the column shows a greater removal efficiency than the batch system due to the continuous dissolution of sulfide and precipitation of arsenic sulfide. At pH 9, where adsorption mainly governs the arsenic removal, the sorption nonlinearity should be considered in the estimation of the column capacity. This study highlighted the importance of understanding reaction mechanism to predict column performance using batch-obtained experimental results.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.05a
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• pp.107-107
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• 2003

The heavy metal cadmium is a xenobiotic toxicant of environmental and occupational concern and it has been classified as a human carcinogen. Inhalation of cadmium has been implicated in the development of emphysema and pulmonary fibrosis, but, the detailed mechanism by which cadmium induces adverse biological effects is not yet known. Therefore, we undertook the investigation of genes that are induced after cadmium exposure to illustrate the mechanism of cadmium toxicity For this purpose, we employed the polymerase chain reaction-based suppression subtractive hybridization technique. We identified 29 different cadmium-inducible genes in human peripheral mononuclear cells, such as macrophage migration inhibitory factor, lysophosphatidic acid acyltransferase-${\alpha}$, enolase-1${\alpha}$, VEGF, Bax, neuron-derived orphan receptor-1, and Nur77, which are known to be associated with inflammation, cell survival, and apoptosis. Induction of these genes by cadmium treatment was further confirmed by semi-quantitative reverse-transcription polymerase chain reaction. Further, we found that these genes were also induced after cadmium exposure in normal human lung fibroblast cell line, WI-38, suggesting potential use of this induction profile to monitor cadmium toxicity in the lung. Next, Nur77, one of cadmium-inducible genes, was further studied since the products of Nur77 are known to be involved in the apoptotic process of lung cells. Following cadmium treatment, Nur77 gene expression was increased at protein-level in A549 cells. Consistently, the reporter containing Nur77 binding sequence was activated by 2.5-fold after exposure to cadmium in reporter gene analysis by transient transfection experiments. When the plasmid encoding dominant negative Nur77 that represses the transcriptional function of wild-type Nur77 was transfected into A549 cells, the expression of Bax was significantly reduced, suggesting that induction of Nur77 was an important process in cadmium-induced apoptosis in the cells. Cadmium induced the expression of Nur77 in vivo, confirming the relevance of the data obtained in viro. Together our results suggest that Nur77 gene expression in exposure to cadmium leads apoptosis of lung cells which may cause pathological changes in lung.