• Journal of dental hygiene science
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• v.18 no.3
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• pp.164-171
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• 2018

To improve the oral health status of Korean people, it is necessary to encourage proper oral hygiene management habits, such as toothbrushing, through appropriate health promotion techniques. Therefore, the purpose of this study was to evaluate the removal of plaque and tooth abrasion using ultra-soft (filament 0.11~0.12 mm) and soft toothbrushes for toothbrushing. The plaque removal was performed using a dentiform and Arti-spray, and the Patient Hygiene Performance (PHP) index was calculated as the sum total score divided by the total number of surfaces. In the abrasivity experiment, according to the number of brushings, a micro Vickers hardness tester was used, and a sample in the range of 280~380 Vickers hardness number was selected. The number of toothbrushing stroke were 1,800 (2 months), 5,400 (6 months), 10,800 (12 months), and 21,600 (24 months). The tooth abrasion was measured using a scanning electron microscope. Statistical analysis was performed using IBM SPSS Statistics 22.0 and a p-value <0.05 was considered significant. According to the results, there was no statistically significant difference in the degree of plaque removal between ultra-soft and soft toothbrushes. The difference in tooth abrasion between before and after toothbrushing was found to be greater with the soft toothbrushes than with the ultra-soft toothbrushes. Therefore, the ultra-soft toothbrush not only lowers tooth damage by reducing tooth abrasion, but also shows a similar ability to remove plaque as soft toothbrushes.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.5
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• pp.380-387
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• 2014

Piper Alpha disaster drew attention to the damage likely to arise from explosions and fires on an offshore platform. And great concerns have been increased to prevent these hazards. Blast wall is one of the passive safety systems; it plays a key part of minimizing the consequences. However, a buckling due to explosion loads is a factor which can reduce the strength of blast wall. The buckling often occurs between web and flange at the center of blast wall. This study aims to find a solution for reinforcing its strength by installing a flat plate at the spot where the buckling occurs. First of all, ANSYS finite element method is adopted to numerically compute the structural resistance characteristic of blast wall by using a quasi-static approach. Sequentially, the impact response characteristics of blast wall are investigated the effect on thickness of flat plate by using ANSYS/LS-DYNA. Finally, pressure-impulse diagrams (P-I diagram) are presented to permit easy assessment of structural response characteristics of stiffened blast wall. In this study, effective use is made to increase structural intensity. of blast wall and acquired important insights have been documented.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.514-521
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• 2010

Epimedium koreanum nakai (EKN) has been used for treatment of reproductive disorders. In this study, we evaluated the effects of EKN water extract on the 2-bromopropane (2-BP) induced reproductive dysfunction. The daily sperm production (DSP), sperm counts and histological changes of reproductive organs were investigated after 4 weeks of EKN administration in 2-BP induced reproductive damaged rats. Although the weights of epididymis and seminal vesicle were increased dose-dependently, they were lower than control group. DSP of EKN-dosing groups were increased compared to control group. In EKN-dosing groups, the number of degenerative seminiferous tubules and the number of epididymal tubules showing epithelial cell vacuolation and decreased spermatozoa in the lumen were significantly (p < 0.01) decreased compared to control group dose-dependently. Significant (P < 0.05 or P < 0.01) increases of the number of sertoli cells, spermatogonia, patchytene spermatocytes, round spermatids and elongated spermatids were observed in EKN-dosing groups compared control group. Consequently, based on the results, EKN water extract could treat 2-BP induced reproductive damages dramatically.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.54-62
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• 1998

This experiment was conducted to find out the effects of ABA and IAA on activities of antioxidant enzymes, antioxidant content, and growth of tobacco under exposure to ozone. The exposure to ozone in tobacco plant significantly decreased plant height, but it did not show any difference in vegetative characteristics except plant height of IAA $10^{-3}$M treated. Total chlorophyll content of NC 82 was dramatically decreased with increase in days after ozone treatment. However, reduction of chlorophyll was minimized when plant growth regulators were treated before ozone exposure. Three days treament of ozone in tobacco increased ascorbic acid of oxidised form, while slightly decreased `in reduced ascorbic acid by IAA treatment. But seven days of ozone treatment showed increase in ascorbic acid and decrease in dehydroascorbic acid. Ozone treatment did not show any difference in glutathione content and glutathione reductase activity when plant growth regulators were treated. Activities of superoxide dismutase(SOD), ascorbate peroxidase(AP) and guaiacol peroxidase(GP) were increased by the exposure to ozone for three days. However, there were no difference in activities of SOD, AP and GP due to exposure to ozone for seven days. These reactions may be interpreted as protective responses to prevent or alleviate the damage of tobacco plant by ozone exposure.

• Journal of Life Science
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• v.21 no.4
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• pp.529-533
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• 2011

Metallothioneins (MT) are a group of low-molecular weight, cysteine-rich, intracellular proteins that are encoded by a family of genes containing at least 10 functional isoforms in human. The expression and induction of these proteins is associated with protection against DNA damage, oxidative stress, and apoptosis. Many studies have shown increased expression of MT in various human tumors, whereas MT is down-regulated in certain tumors such as hepatocellular carcinoma and liver adenocarcinoma. Hence, the expression of MT is not universal to all human tumors but may depend on the differentiation status and proliferative index of tumors, along with other tissue factors and gene mutations. Using Northern blot analysis, we found that laminin induced expression of MT-1 in HSG and PC12 cells, which can be differentiated by laminin, but had no effect on MB-231, MDA-435, and PC-3 cells, which cannot be differentiated by laminin. In addition, we analyzed the expression level of the MT-1 gene in five prostate cancer cell lines possessing different metastatic potential. The expression of MT-1 in normal and less malignant cells (RWPE-1 and WPE1-NA22) was high and up-regulated by laminin, whereas the expression of MT-1 in WPE1-NB14, WPE1-NB11, and WPE1-NB26 cells (malignant) was extremely low and not elevated by laminin. These results suggest that the MT-1 gene is involved in laminin-mediated differentiation and affects the metastatic potential of tumor cells.

• Journal of Life Science
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• v.19 no.8
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• pp.1112-1118
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• 2009

In the present study, the effects of muddy water were compared and examined on the fish inhabiting Imha reservoir, E. erythropterus, H. labeo and Z. platypus in Cypriniformes, S. asotus in Siluriformes and S. scherzeri in Perciformes. In the gills of fish in muddy water, the secondary lamellae of fish in Cypriniformes showed more irregular gaps and more winding than those in Siluriformes and Perciformes. Also, the edema and detachment of epithelial cells was more detected in the gills in Cypriniformes, but clubbing was frequently detected in Perciformes and Siluriformes. Also, we found that muddy debris and minute particles attached to lamellae were frequently detected in Perciformes and Cypriniformes. The glomerulus in the kidney was much more constricted in Z. platypus in Cypriniformes. As a result, it is proposed that fish in Cypriniformes are more affected by muddy water. In the changes of blood components, which might be affected by muddy water, the concentrations of TP, ALB, TG, CHOL and A/G ratio, were high in Cypriniformes, and inorganic matters were abundant in Siluriformes. In addition, AST activity was relatively higher than ALT and both activities were higher in Cypriniformes than in Siluriformes. Taken together, the change in blood plasma may be caused by the reduction in voracity in the wake of muddy water, which results in tissue damage.

• Korean Journal of Plant Resources
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• v.29 no.1
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• pp.39-45
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• 2016

Pink Rot on melon and White Stain Symptom on grape are caused by Trichothecium roseum, one of the most important diseases of grape and melon. These diseases have been occurred in national-wide in Korea and causes irreversible damage on the grape and the melon at harvest season. This research presents the evaluation of the capacity of Bacillus subtillis HK2 to protect both melon and grape against T. reseum and establishes its role as a biocontrol agent. In this study, we isolated a Bacillus strain HK2 from rhizosphere soil, identified it as Bacillus subtillis by 16S rRNA analysis and demonstrated its antifungal activity against T. roseum. Under I-plate assay it was observed that the effect of hyphal growth inhibition was not due to production of volatile compounds. The optimum culture condition of HK2 was found at 30℃ and initial pH of 7.0. Application of HK2 culture suspension reduced 90.2% of white stain symptom on grape as compared to control, resulting in greater protection to grape against T. roseum infestation. Butanol extract of HK2 culture purified using flash column chromatography. The antifungal material was a polar substance as it showed antifungal activity in polar elute. Therefore, our results indicated a clear potential of B. subtilis HK2 to be used for biocontrol of Pink rot in melon and white stain symptom on grape caused by T. roseum.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.976-982
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• 2005

Abilities of various edible plants and natural antioxidants to protect brain against oxidative damages were evaluated using brain homogenate of perfused Sprague-Dawley rat. Oxidative damage, expressed as lipid peroxidation (LPO), indicating total quantity of malondialdehyde and 4-hydroxyalkenal, increased from 4.1 to 6.9nmol/mg protein by treatment of $2.5{\mu}M$ ferrous sulfate and 7.5mM hydrogen peroxide as source of reactive oxygen species (ROS) on brain homogenate for 10min at $37^{\circ}C$ Mallow(88%) in leafy vegetables, small potato (93%) in root vegetables, green red pepper (76%) in fruit vegetables, and avocado (96%) in fruits showed highest LPO inhibition capacities. Ability of mushrooms decreased in order of nameko, shiitake, pine mushroom, oyster mushroom, and new type pine mushroom. Among natural antioxidants tested, (+)catechin (91%), (-)epigallocatechin gallate (85%), (-)epicatechin gallate (83%), and kaempferol(83%) showed high LPO inhibition capacities.

• Preventive Nutrition and Food Science
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• v.8 no.4
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• pp.383-389
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• 2003

This study was conducted to investigate the antioxidative effects of Paeonia lactiftora Pall. (PL) seed extracts and Forsythia viridissima Lindl. (FVL) extracts on the antioxidative defense system and lipid peroxidation in the erythrocytes of rats fed a high-cholesterol diet. Sprague-Dawley male rats weighing 100 10 g were randomly assigned to nine experimental groups and fed 0.5 % cholesterol. The HC group did not receive any supplement, while the MP group was supplemented with 0.1 % methanol extract of PL seed, the MP2 group with 0.2 % methanol extract of PL seed, the EP1 group with 0.05 % ether-soluble fraction of PL seed, the EP2 group with 0.1 % ether-soluble fraction of PL seed, the MS1 group with 0.05 % methanol extract of FVL, the MS2 group with 0.1 % methanol extract of FVL, the ES group with 0.025% ethyl acetate-soluble fraction of FVL, and the ES2 group with 0.05 % ethyl acetate-soluble fraction of FVL. The experimental diets were fed ad libitum for 3 weeks. The erythrocyte SOD activity in the EP1 and EP2 groups increased 38% and 59%, respectively, when compared with the HC group, while the erythrocyte GSHpx activity in the EP1, EP2, and ES2 groups increased 30%, 31 %, and 29%, respectively, when compared with the HC group. The level of erythrocyte TBARS was significantly lower in the MP2, EP1, and EP2 groups than in the HC group, yet the level of serum TBARS was significantly lower in the all supplemented groups than in the HC group. The level of serum HDL- TBARS was significantly lower in the EP1 and EP2 groups than in the HC group, while the level of serum LDL- TBARS was significantly lower in the all the supplemented groups than in the HC group. Accordingly, the results indicated that the PL seed extracts and FVL extracts reduced oxidative damage by activating the antioxidative defense system in the erythrocytes of rats fed a high-cholesterol diet.

• Herbal Formula Science
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• v.23 no.2
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• pp.189-198
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• 2015

Objectives : Sparganii Rhizoma is frequently used in traditional herbal medicine for treatment of blood stasis, amenorrhea and functional dyspepsia and has been reported to exhibit anti-oxidant, anti-proliferation and anti-angiogenesis peoperties. In this study, we investigated the cytoprotective effect and underlying mechanism of Sparganii Rhizoma water extract (SRE) against oxidative stress-induced mitochondrial dysfunction and apoptosis in hepatocyte. Methods : To determine the effects of SRE on oxidative stress, we induced synergistic cytotoxicity by co-treatment of arachidonic acid (AA) and iron in the HepG2 cell, a human derived hepatocyte cell line. Results : Treatment of SRE increased relative cell viability and altered the expression levels of apoptosis-related proteins such as Bcl-xL, Bcl-2 and procaspase-3. And SRE also inhibited the mitochondrial dysfunction and excessive reactive oxygen species production induced by AA+iron. In addition, SRE activated of AMP-activated protein kinase (AMPK), a potential target for cytoprotection, by increasing the phosphorylation of AMPKα at Thr-172. Morever, SRE increased phosphorylation of acetyl-CoA carboxylase, a direct downstream target of AMPK. Conclusion : These results indicated that SRE has the ability to protect against oxidative stress-induced hepatocyte damage, which may be mediated with AMPK pathway.