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Cheongju, South Korea

Keum Y.-S.,Dongguk University | Choi B.Y.,Seowon University
Molecules | Year: 2014

Extracellular and intracellular oxidants or electrophiles are key contributors to the damages in cellular macromolecules, such as DNA, proteins and lipids. Nrf2 is a master transcription factor that modulates a cellular antioxidant response program and plays an important role in the protection against oxidants and electrophiles. Keap1 is a regulator of Nrf2 by serving as a substrate adaptor for Cullin3-dependent E3 ubiquitin ligase. While Nrf2 activation is a feasible strategy for treatment of age-related diseases, aberrant Nrf2 activation also confers a selective growth advantage of tumor cells during chemotherapy or radiotherapy. In the present review, we provide an overview of the Keap1-Nrf2-ARE system, the domain organization of Nrf2 and Keap1, and the regulatory mechanisms of Nrf2 proteolysis by Keap1. We also discuss how Nrf2 prevents tumor promotion, hampers the sensitivity of selected tumors against chemotherapy or radiotherapy, and reprograms the metabolism to facilitate the tumor proliferation. Finally, we illustrate the current status in the development of Nrf2 chemical activators and inhibitors for the use of potential chemopreventive agents and chemotherapeutic adjuvants, respectively.

Lee J.-E.,Seowon University
Journal of the Korean Society of Food Science and Nutrition | Year: 2015

The purpose of this study was to examine dietitians' perception of importance about standards of foodservice management associated with long-term care hospital accreditation. This study was carried out through a postal survey consisting of 500 questionnaires, and 157 returned questionnaires were used in the statistical analysis. The results were summarized as follows. Average scores of perception of importance were 4.54/5 points in foodservice production management domain, 4.56/5 points in foodservice facilities management domain, and 4.70/5 points in foodservice sanitation domain. The average scores of importance of long-term care hospitals without accreditation were significantly (P<0.05) lower than those of hospitals with accreditation in items of ‘establishment of ventilation equipment in kitchen’, ‘establishment of hand-washstand in toilet (warm-water, soap)’, ‘setup of sterilizing foothold in entrance of kitchen and toilet’, ‘division and use of knife, chopping board, gloves, and utensils before and after cook’, ‘establishment of cleaning plan and cyclic practice’, and ‘recording of receiving diary’. Results indicate that there is a need to supplement a casebook of regulations by suggesting detailed and critical limits in the case of below average points of importance. A manual, including HACCP standards for foodservice management of long-term care hospitals, is needed, along with education and webpage for comparing notes on accreditation of long-term care hospitals. © 2015, Korean Society of Food Science and Nutrition. All rights reserved.

The purpose of this study is to examine the relationship between the protein supplements intake satisfaction level and repurchase intention of university students majoring in physical education and verify the mediation effects of word-of-mouth intention. To achieve the purpose of this study, 700 university students majoring in physical education from 10 universities in Korea were selected from October 2013 to December 2013 as the target of this study through the cluster random sampling and data of 228 university students who had experience in the intake of protein supplements among them was analyzed. The composite reliability of each factor was in between 0.869 and 0.958, and the convergent validity and discriminant validity were verified. SPSS 18.0 and Amos 22.0 were utilized as data processing methods and the verification of significance on the medication effects and indirect effects of word-of-mouth intention was carried out using the frequency analysis, correlation analysis, CFA, SEM, and Amos bootstrapping. The result is as follows. The protein supplements intake satisfaction level had a positive effect on the word-of-mouth intention and the word-of-mouth intention had a positive effect on the repurchase intention. Also, it was shown that the word-of-mouth intention played a full mediation role between the intake satisfaction level and the repurchase intention. © 2016 - IOS Press and the authors. All rights reserved.

Kim C.H.,Seowon University
Journal of Applied Biological Chemistry | Year: 2014

A gene encoding thermostable pectinase (TmPec) was isolated from hyperthermophilic microorganism, Thermotoga maritima. The open reading frame (ORF) of TmPec gene is 1,104 bp long and encodes 367 amino acid residues with a molecular weight of 40,605 Da. To analyze the enzymatic activity and biochemical properties, the ORF of TmPec gene excluding putative signal sequence of 27 amino acids was introduced into the E. coli expression vector, pRSET-B, and overexpressed in E. coli BL21. Protein concentration of purified recombinant TmPec was 1.1 mg/ mL with specific activity of 56 U/mg protein on pectin. The recombinant TmPec showed the highest activity at around 85-95°C, and at around pH 6.5. It was stable at temperature below 85°C. In the presence of Ca2+, the activity of recombinant TmPec was increased to 146.3% of normal level. In contrast, Ba2+ and Mn2+ showed strong inhibition to the recombinant TmPec. © The Korean Society for Applied Biological Chemistry 2014.

The aim of this work was to obtain the polysaccharides having good biological activities from low-quality fresh ginseng by employing a simple high-pressure homogenization process with very high shear stress of 4,900,000 (1/sec). The optimal condition of this process was to obtain 2100x103 (g/mol) molecular weight of a crude polysaccharide. This polysaccharide was found to be composed of two polysaccharide fractions: F1, 856 x103 (g/mol) and F2, 1137 x103 (g/mol) respectively and interestingly enough, the fraction 2, F2 had high contents of uronic acid. This fraction was also found to have high biological activity, compared to the F1. The F2 polysaccharide showed high suppression of NO production. These results strongly indicate that high-pressure homogenization can efficiently destroy the crystal structure of intact ginseng polysaccharides as well as to break down the hard cell walls of low quality fresh ginseng, resulting in yielding the polysaccharides.

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