• Molecules and Cells
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• 제25권3호
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• pp.397-406
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• 2008

Computational modeling of signal transduction is currently attracting much attention as it can promote the understanding of complex signal transduction mechanisms. Although several mathematical models have been used to examine signaling pathways, little attention has been given to crosstalk mechanisms. In this study, an attempt was made to develop a computational model for the pathways involving growth-factor-mediated mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3'-kinase/protein kinase B (PI3K/Akt). In addition, the dynamics of the protein activities were analyzed based on a set of kinetic data. The simulation approach integrates the information on several levels and predicts systems behavior. The in-silico analysis conducted revealed that the Raf and Akt pathways act independently.

• Molecules and Cells
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• 제27권2호
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• pp.211-215
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• 2009

Toll-like receptors (TLRs) play a critical role in sensing microbial components and inducing innate immune and inflammatory responses by recognizing invading microbial pathogens. Lipopolysaccharide-induced dimerization of TLR4 is required for the activation of downstream signaling pathways including nuclear factor-kappa B ($NF-{\kappa}B$). Therefore, TLR4 dimerization may be an early regulatory event in activating ligand-induced signaling pathways and induction of subsequent immune responses. Here, we report biochemical evidence that 6-shogaol, the most bioactive component of ginger, inhibits lipopolysaccharide-induced dimerization of TLR4 resulting in the inhibition of $NF-{\kappa}B$ activation and the expression of cyclooxygenase-2. Furthermore, we demonstrate that 6-shogaol can directly inhibit TLR-mediated signaling pathways at the receptor level. These results suggest that 6-shogaol can modulate TLR-mediated inflammatory responses, which may influence the risk of chronic inflammatory diseases.

• KSBB Journal
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• 제23권6호
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• pp.535-540
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• 2008

In this study, the effects of several factors such as initial nitrate concentration, C/N ratio, biomass amount and external carbon source on denitrification process were investigated using synthetic wastewater and sludge obtained from wastewater treatment facility. As a result, the condition of lower initial nitrate concentration was increased to the removal rate of nitrate than that of high concentration. The increases of C/N ratio and initial biomass amount were linearly enhanced the removal rate. The use of ethanol as external carbon source was shown the highest removal yield than that of others.

• The Korean Journal of Physiology and Pharmacology
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• 제12권1호
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• pp.1-6
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• 2008

Ribbon-type antisense oligonucleotide to TGF-${\beta}1$ (TGF-${\beta}1$ RiAS) was designed and tested to prevent or resolve the fibrotic changes induced by $CCl_4$ injection. When Hepa1c1c7 cells were transfected with TGF-${\beta}1$ RiAS, the level of TGF-${\beta}1$ mRNA was effectively reduced. TGF-${\beta}1$ RiAS, mismatched RiAS, and normal saline were each injected to mice via tail veins. When examined for the biochemical effects on the liver, TGF-${\beta}1$ mRNA levels were significantly reduced only in the TGF-${\beta}1$ RiAS-treated group. The results of immunohistochemical studies showed that TGF-${\beta}1$ RiAS prevented the accumulation of collagen and ${\alpha}$-smooth muscle actin, but could not resolve established fibrosis. These results indicate that ribbon antisense to TGF-${\beta}1$ with efficient uptake can effectively prevent fibrosis of the liver.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.322-324
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• 2003

Leaf C:N ratio is a new factor in the field of biochemical inversion with hyperspectral data. Effects of common-used spectral transformations including log(R), log(1/R), 1/R, etc. from 400nm to 2490nm on its inversion are compared. Results show that their effects on statistical modeling are not apparent. Continuum removal is used on original reflectance in the range of 2030nm to 2220nm, in which exists an apparent absorption peak due to cellulose, lignin, protein, etc. The effect is distinctive and tends to improve the precision of C:N ratio inversion. Further, it is a robust and physically based transformation.

• 대한화장품학회지
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• 제26권2호
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• pp.41-50
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• 2000

- Biochemical studies show that in the process of mixed melanogenesis, cysteinyldopas are produced first which are next oxidized to give pheomelanin. After all of the cysteine is consumed, eumelanin is then deposited on the preformed pheomelanin. - In vitro and in vivo studies show that tyrosinase activity is the most important factor that regulates the switch of melanogenesis, with higher activities increasing melanogenesis, especially eumelanogenesis. - In culturted melanocytes, the tyrosine to cysteine ratio is critical in determining the eumelanin to pheomelanin ratio. - Our HPLC method to analyze eumelanin and pheomelanin has become a useful tool in the study of melanogenesis regulation. There are many problems to be solved before we fully understand the regulation of melanogenesis. Mutations in mouse models are ideal models for studying the genetic and molecular control of melanogenesis. Even in the mouse models, it is not known how cysteine is excluded from being incorporated into melanins in black and other eumelaninc mice, Conversely, it is not known how cysteine is continuously incorporated into pheomelanin in lethal yellow and recessive yellow mice.

• Archives of Pharmacal Research
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• 제16권2호
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• pp.140-146
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• 1993

A colostral protein that augments natural killer (NK) cell activity was isolated from bovine colostrum. This protein, designated matemal immunity enhancing factor (MIEF), increased NK cell-mediated cytotxicity against human tumor targets wheb added to cultures of resting peripheral blood lymphocytes. The NK cell stimulatory activity of the MIEF was demonstrated at the concentrations as low as 0.1-0.01 $\mu$g/ml. Purified MIEF showed an apparent molecular weight of 22,000 in SDS-polyacrylamide gel electrophoresis. The unusual biochemical characteristics of the MIEF distinguish it from other cytokines. The MIEF was soluble at a cold tgemperature, and precipitated by raising the temperature. This themal precipitability was reversible, and dependent on the concentration, pH and ionic strength. Maximal precipitation was observed at neutral pH, and higher ionic strength.

• Journal of Ginseng Research
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• 제39권3호
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• pp.206-212
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• 2015

Background: Ginseng total saponin (GTS) contains various ginsenosides. These ginsenosides are widely used for treating cardiovascular diseases in Asian communities. The aim of this study was to study the effects of GTS on cardiac injury after global ischemia and reperfusion (I/R) in isolated guinea pig hearts. Methods: Animals were subjected to normothermic ischemia for 60 minutes, followed by 120 minutes of reperfusion. GTS significantly increased aortic flow, coronary flow, and cardiac output. Moreover, GTS significantly increased left ventricular systolic pressure and the maximal rate of contraction ($+dP/dt_{max}$) and relaxation ($-dP/dt_{max}$). In addition, GTS has been shown to ameliorate electrocardiographic changes such as the QRS complex, QT interval, and RR interval. Results: GTS significantly suppressed the biochemical parameters (i.e., lactate dehydrogenase, creatine kinase-MB fraction, and cardiac troponin I levels) and normalized the oxidative stress markers (i.e., malondialdehyde, glutathione, and nitrite). In addition, GTS also markedly inhibits the expression of interleukin-$1{\beta}$ (IL-$1{\beta}$), IL-6, and nuclear factor-${\kappa}B$, and improves the expression of IL-10 in cardiac tissue. Conclusion: These data indicate that GTS mitigates myocardial damage by modulating the biochemical and oxidative stress related to cardiac I/R injury.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.356-358
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• 2003

각질형성세포의 배양법이 개발 후 피부 결손 부위의 치료에 인체 각질형성세포를 배양하여 얻어진 표피를 이식하거나 세포부유물을 도포하는 기존의 방법들은 trypsin 처리 과정을 거치면서 배양된 세포의 부착능력을 가진 단백질이 손상되어 성공적인 피부 재생이 불가능하다. 이 연구에서는 면역결핍 생쥐 모델에서 인간 피부 각질형성에포와 EGF-피브린 고분자 혼합물을 분사하여 피부의 전층 상처를 재생하였다. 조직학 검사와 면역화학검사를 통하여 각질형성세포와 EGF-피브린 고분자를 함께 분사한 경우 이식된 인간 표피세포에 의한 빠른 표피재생을 확인할 수 있었다. 이 피부 재생술은 기존의 배양된 인공피부 sheet의 이식을 이용한 피부재생법에 비해 여러 가지 장점을 가지고 있으므로, 앞으로 화상이나 피부궤양과 같은 피부결손의 효율적인 새로운 치료법으로 사용되어질 수 있을 것이다.

• 대한지역사회영양학회지
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• 제14권3호
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• pp.340-353
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• 2009

It is very important to screen the elderly for nutritional risk, because nutritional status is a critical factor to maintain their health. Some nutrition checklists used in Korea for the elderly are from other countries. Reliability of those checklist in Korea is not studied enough. This survey was done for the elderly over 65-years-old who live in Hong-cheon, An-dong, Dam-yang and Yeon-gi in Korea (subject; summer: 146, winter: 145) to study the reliability of DETERMINE checklist which is adopted widely in Korea. Using the score of DETERMINE checklist, the elderly were divided as high, middle and low risk groups. For nutritional assessment for those elderly, dietary assessment using 24 recall, anthropometry, biochemical assessment and health condition were used. Results for the checklist showed that percentage below EAR for energy intake and protein intake in winter were higher in the high risk group than other groups. The intakes of phosphorus and iron and most vitamins were below the DRI. The percentage of subjects with intake below DRI was highest in the high risk group. Sensitivity, specificity, and positive predictive values using the DETERMINE were calculated using 6 point as a cut-off point. Subjects were divided into two groups by MAR (MAR < 0.75:undernutrition, MAR < 0.75 : normal). Sensitivity recorded 49.4% and 34.3%, specificity did 61.9% and 65.4 and Positive predictive value did 62.1% and 46.0% each for summer and winter. Results of screening using DETERMINE Checklist were not matched with dietary assessment but not with anthropometric and biochemical measurement. In conclusion DETERMINE 'Checklist' is shown be a good screening tool for finding out risk groups for dietary intake in the elderly, It needs to verify reliability and validity through large-scale survey.