• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.29-29
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• 2001

Leukocytes are important elements in the host defense against microbial infections. A variety of antimicrobial peptides named as the cathelicidin family have been identified from leukocytes. PMAP-23 derived from porcine myeloid cells is an antimicrobial peptide belong to the cathelicidin family. PMAP-23 was reported to have potent growth inhibition activity against bacterial and tumor cells with no hemolytic activity.(omitted)

• Bulletin of the Korean Chemical Society
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• v.22 no.4
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• pp.388-394
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• 2001

Quantitative Structure-Activity Relationship (QSAR) have been established of 57 fluorovinyloxyacetamides compounds to correlate and predict EC50 values. Genetic algorithm (GA) and multiple linear regression analysis were used to select the descriptors and to generate the equations that relate the structural features to the biological activities. This equation consists of three descriptors calculated from the molecular structures with molecular mechanics and quantum-chemical methods. The results of MLR and GA show that dipole moment of z-axis, radius of gyration and logP play an important role in growth inhibition of barnyard grass.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.175.4-176
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• 2003

Our long-term research goals involve the SARs study and the synthetic procedure development of wogonin and its analogs. We investigated efficient synthetic pathways of wogonin and its bioisosteres in a large quantity to decipher the structural requirements for anti-inflammatory activities. We plan to serially delete or modify the 5,7-dihydroxyl groups of wogonin to observe the effects of the hydroxyl groups on anti-inflammatory activity. Also we modofied the 8- methoxy group on a ring since it is known to be necessary for biological activity. (omitted)

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.367-370
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• 2018

Lysozyme is an antibacterial enzyme that is found in most of body fluids. Lysozyme in tears plays a primary role in protecting eye from harmful environments; if lysozyme is degraded or inhibited, eyes are likely to be more vulnerable to bacterial infection. In this study, lysozyme activity was evaluated according to varying concentrations of heavy metals, copper, zinc, cobalt and manganese and light metal, calcium that are frequently found in airborne particulate matters and was assayed using a dye-quenching lysozyme substrate, Micrococcus lysodeikticus. Less fluorescence intensity was observed with increasing amounts of copper, zinc, manganese and cobalt but not with calcium suggesting that these metals have some affinity with lysozyme and inhibit lysozyme activity. When albumin, the second most common protein in tears, was added on the reaction of lysozyme and metals, lysozyme activity was partially restored. This finding suggests that the albumin might protect damage caused by metals on lysozyme. To identify whether the decrease in enzymatic activity was related to structural changes of lysozyme, SDS-PAGE was conducted and only with copper did lysozyme show marked smearing bands on the SDS-gel, meaning that copper degraded lysozyme consistent with the sharpest activity decrease.

• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.343-351
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• 2021

Screening was conducted using 200 kinds of plant extracts to explore herbicide-activated components of plant origin. We separated and purified active substances and elucidated chemical structures using Ligularia stenocephala M., which has strong activity and has not yet been studied. When the solvent fractions of the leaves of Ligularia stenocephala M. were tested for their herbicidal activity, ethyl acetate and chloroform layer showed an inhibition rate of 95.2% and 94.1%, respectively. In particular, the chloroform layer exerted more than 50% herbicidal activity at 10 ppm. From the chloroform layer with the highest herbicidal activity, we isolated three herbicidal active compounds using stepwise chromatography, specifically silica gel or octadecyl silica (ODS) column chromatography, Sep-pak cartridges, and high performance liquid chromatography (HPLC). Based on the analysis of the active compounds using electron ionization mass spectroscopy (EI-MS), ¹H-NMR, and ¹³C-NMR, we identified the active compounds as euparin, 5,6-dimethoxy-2-isopropenylbenzofuran, and liguhodgsonal. When the herbicidal activity of the identified compounds was tested, euparin showed selective herbicidal activity for lettuce at 10^-3 M, and both liguhogsonal and 5,6-dimethoxy-2-isoprophenylbenzofuran exerted selective activity for rice and Echinochloa crus-galli.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.227-237
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• 2021

Considerable attention has been given to Comprehensive School Physical Activity Program(CSPAP) to promote children's health and physical activity(PA) in Sport Pedagogy. This study examined the structural characteristics and effects of CSPAP using literature review analysis to comprehensively overview CSPAP model, which emphasizes the necessity of promoting PA and establishing a healthy lifestyle. Based on the results of the study, CSPAP provide health-enhancing PA in conjunction with schools, communities, and family. CSPAP suggested the importance of PA promotion in sport pedagogy via the uptake of moderate-to-vigorous physical activity(MVPA) accrual in line with the goal of high-quality physical education.

• Journal of Applied Biological Chemistry
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• v.58 no.1
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• pp.1-3
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• 2015

This study investigated the inhibitory activities of 2-hydroxyquinoline and its analogs against ${\alpha}$-glucosidase and ${\alpha}$-amylase. Based on the $IC_{50}$ values of 2-hydroxyquinoline analogs tested against ${\alpha}$-glucosidase and ${\alpha}$-amylase, 2-hydroxyquinoline had potent inhibitory activity (64.4 and $130.5{\mu}g/mL$, respectively), while 2-methyl-8-hydroxyquinoline showed weakly inhibitory activity (90.7 and $215.4{\mu}g/mL$, respectively). 2-Methylquinoline demonstrated no activity against ${\alpha}$-glucosidase and ${\alpha}$-amylase. In conclusion, 2-hydroxyquinoline analogs, with the existence of a methyl group and hydroxyl on quinoline, can be useful as a new diabetes treatment.

• 한국경영정보학회:학술대회논문집
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• 2007.11a
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• pp.123-128
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• 2007

It has been argued that Enterprise systems (ES) implementations are overshadowed by a high failure rate despite their promised benefits. One of the commonly cited reasons for ES implementation failures in the context of mandatory use is end-user's unwillingness or sabotage to adopt or use systems. Considering that the appropriate management of expectations may play an important role in making positive behavior toward newly implemented systems, this study examines the effect of outcome expectations on the system use activity in the mandatory use context of information systems from the Social Cognitive Theory perspective. Structural equation model analysis using LISREL 8.7 provides significant support for the proposed relationships. The empirical results suggest that outcome expectations and user satisfaction have positive effects on system use activity conceptualized by immersion, reinvention, and learning. Theoretical and practical implications of the study shed some light on how to improve system use activity in the mandatory use context of information systems.

• Mycobiology
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• v.48 no.1
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• pp.51-57
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• 2020

A polysaccharide (LVP) was purified from fruiting body of Lentinus velutinus by ethanol precipitation fractionation and DEAE and Sephadex G-100 column chromatography. The yield of purified polysaccharide was 0.025%. Molecular characteristics of LVP were determined by gel permeation chromatography, FT-IR spectroscopy, and thin-layer chromatography. Our results revealed that LVP is a polysaccharide composed of only glucose units, and has a molecular weight of 336 kDa. Biological activity assays indicated that LVP exhibits both cytotoxic and antioxidant activity. LVP showed specific cytotoxicity against cancer cells (HeLa and HepG2 cells), and alterations in cancer cell morphology were found after LVP treatment.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.108-114
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• 2015

The purpose of this study is to find the relationships among communication competency, social network centrality(trust centrality and knowledge sharing centrality), discussion performance, and online boarding activity in the team based learning situation. For investigating this topic, 44 students are participated in the classes of educational technology. In order to find out the relationships among communication competency, social network centrality, discussion performance, and online boarding activity, compared t-test and path analysis are used. Followings are the results of the research: (a) Communication competency is improved significantly after team based learning. (b) Trust centrality effects significantly on the knowledge sharing centrality. (c) Knowledge sharing effects significantly on discussion performance. (d) Trust centrality effects on the online boarding activity in the team based learning.