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Influence of $TiO_2$ Concentrations and Irradiation Lights on the Photocatalytic Reaction for Inhibiting Growth of Streptococcus mutans ($TiO_2$ 농도 및 여기광에 따른 광촉매 반응이 Streptococcus mutans의 생장에 미치는 영향)

  • Kang, Si-Mook;Lee, Hae-Na;Kim, Hee-Eun;Kim, Baek-Il
    • Journal of dental hygiene science
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    • v.14 no.3
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    • pp.319-324
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    • 2014
  • The aim of this study was to evaluate influences of titanium dioxide ($TiO_2$) concentrations and irradiation times on growth of Streptococcus mutans when irradiated by visible light (405 nm wavelength) and by ultraviolet light (254 nm wavelength). To find the optimal antibacterial concentration of $TiO_2$, 0.01, 0.1, 1.0, and 10.0 mg/ml $TiO_2$ suspension was prepared with sterilized distilled water. S. mutans cultured media was added to $TiO_2$ solution to set the final cell count to $10^4CFU/ml$. The photocatalytic reaction was induced by irradiating 254 nm and 405 nm lights for 10 minutes. To compare the bactericidal activities according to irradiation times, all photocatalytic reaction was carried out with 0.1 mg/ml $TiO_2$ for 0, 10, 20, 30, and 40 minutes with both lights. After the photocatalytic reaction, $100{\mu}m$ of the reaction mixture was immediately plated on brain heart infusion agar. These plates were placed at 5% $CO_2$, $37^{\circ}C$, for 24 hours and the bacterial colonies were counted. All experiments were performed in quintuplicate. One-way ANOVA was used to determine whether there were any significant differences between the $TiO_2$ concentrations or the irradiation times. The most effective concentration of $TiO_2$ for its photocatalytic bactericidal effect on S. mutans was 0.1 mg/ml when irradiated with 254 nm and 405 nm lights. The longer the irradiation time, the bigger the bactericidal effect for both wavelengths. Over 99% of bacteria in the inoculum were killed after irradiation with 254 nm for 20 minutes and with 405 nm for 40 minutes. In conclusion, a photocatalytic reaction of $TiO_2$ induced by visible light of 405 nm constitutes the bactericidal effect on S. mutans.

Antioxidative Activity of Rumex crispus L. Extract (소리쟁이 추출물의 항산화 효능)

  • Rhim, Tae-Jin;Choi, Moo-Young;Park, Hee-Juhn
    • Korean Journal of Plant Resources
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    • v.25 no.5
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    • pp.568-577
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    • 2012
  • The objective of this study was to investigate the antioxidative capacity of ethanol extracts from Rumex crispus L. The concentration of R. crispus L. extract at which DPPH radical scavenging activity was inhibited by 50% was 2.15 mg/mL, which was lower than that of ${\alpha}$-tocopherol (0.43 mg/mL), as compared to 100% by pyrogallol as a reference. Total antioxidant status was examined by total antioxidant capacity against ABTS radical reactions. Total antioxidant capacities of R. crispus L. extract at concentrations of 0.1 and 1 mg/mL were 0.47 and 2.33 mM Trolox equivalents, respectively, which were higher than those of ${\alpha}$-tocopherol. Superoxide scavenging activities of R. crispus L. extract at concentrations of 0.1 and 1 mg/mL were 21.5 and 78.9%, respectively, which were not significantly (p>0.05) different from those of catechin. Oxygen radical absorbance capacities of R. crispus L. extract at concentrations of 20 and 100 ${\mu}g/mL$ were 62.5 and 156.4 ${\mu}M$ Trolox equivalents, respectively, which were lower than those of ascorbic acid. Cupric reducing antioxidant capacities of R. crispus L. extract at concentrations of 0.1 and 1 mg/mL were 0.28 and 1.88 mM Trolox equivalents, which were similar or significantly (p<0.05) higher than those of ${\alpha}$-tocopherol, respectively. R. crispus L. extract prevented supercoiled DNA strand breakage induced by hydroxyl radical and peroxyl radical. Total phenolic contents of R. crispus L. extract at concentrations of 0.5 and 5 mg/mL were 0.58 and 3.85 mM gallic acid equivalents, respectively. R. crispus L. extract at concentration of 0.1 and 0.5 mg/mL inhibited 0.2 mM tert-butyl hydroperoxide-induced cytotoxicity by 38.5 and 63.5%, respectively, in HepG2 cell culture system. Thus, strong antioxidant and cytotoxicity-inhibiting effects of R. crispus L. extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation as well as high levels in total phenolic contents.

Effect of buchu (Allium tuberosum) on lipid peroxidation and antioxidative defense system in streptozotocin-induced diabetic rats (부추가 Streptozotocin 유발 당뇨쥐의 지질과산화와 항산화방어체계에 미치는 영향)

  • 송영선;정현실;노경희;조혜연;박지영;최춘연;권태완
    • Journal of Life Science
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    • v.13 no.3
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    • pp.333-342
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    • 2003
  • The pathogenic effort of high glucose, possibly in concert with fatty acids, is mediated to vascular complications of diabetes via increased production of reactive oxygen species(ROS), reactive nitrogen species(RNS), and subsequent oxidative stress. This study was carried out to investigate the suppressive effect of buchu(Allium tuberosum) on oxidative stress in streptozotocin(STZ)-induced diabetes in Sprague Dawley male rats. The effect of buchu supplementation (10%) on lipid peroxidation, and antioxidative defense system in blood and liver was compared among normal rats fed basal diet(normal) and diabetic rats fed basal diet(DM-control) or 10% buchu-supplemented diet(DM-buchu). Diabetes was experimentally induced by the femoral muscle injection of 50 mg STZ per kg of body weight. Animals were sacrificed after 4 wks of experimental diets feeding. The induction of diabetes by STZ elevated the level of lipid peroxidation represented by thiobarbituric acid-reactive substances(TBARS) and conjugated dienes in plasma, LDL, liver, and erythrocytes. 10% buchu-supplemented diet significantly reduced the levels of conjugated dienes in erythrocytes(p<0.05) and lowered TBARS in liver and LDL to the levels of control. Induction of diabetes by STZ elevated Mn-superoxide dismutase(Mn-SOD) activity and lowered activities of glutathionine reductase(GSH-red) and glutathionine peroxidase(GSH-px). Catalase activity was not affected by the induction of diabetes by STZ. However, buchu supplementation to diabetic rats significantly elevated catalase activity(p<0.05) and slightly elevated GSH-px and GSH-red activities in liver. GSH levels of blood and liver were lowered or not changed by induction of diabetes by STZ, respectively, while buchu supplementation to diabetic rats significantly elevated hepatic GSH level (p<0.05). In conclusion, it can be concluded that buchu might be a food source to attenuate oxidative stress in diabetic patients by inhibiting lipid peroxidation, by increasing hepatic GSH level, and by inducing anti-oxidative enzyme systems.

Effects of Halogenated Compounds on in vitro Fermentation Characteristics in the Rumen and Methane Emissions (할로겐 화합물의 첨가가 반추위 발효성상과 메탄생성에 미치는 영향)

  • Hwang, Hee-Soon;Ok, Ji-Un;Lee, Shin-Ja;Chu, Gyo-Moon;Kim, Kyoung-Hoon;Oh, Young-Kyoon;Lee, Sang-Suk;Lee, Sung-Sill
    • Journal of Life Science
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    • v.22 no.9
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    • pp.1187-1193
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    • 2012
  • This study was conducted to evaluate effects of halogenated compounds on in vitro rumen fermentation characteristics and methane emissions. A fistulated Holstein cow of 650 kg body weight was used as a donor of rumen fluid. Five kinds of halogenated compounds (bromochloromethane (BCM), 2-bromoethane sulfonic acid (BES), 3-bromopropanesulfonic acid (BPS), chloroform (CLF), and pyromellitic diimide (PMDI) known to inhibit methyl-coenzyme M reductase activity were added to an in vitro fermentation incubated with rumen fluid. The microbial population including bacteria, protozoa, and fungi were enumerated, and gas production including methane and fermentation characteristics were observed in vitro. The pH values ranged from 6.25 to 6.72 in all the treatments, and these showed a similar level at 48 hr. The total gas production in the treatments showed a similar pattern with C at 48 hr, whereas methane production in the treatments was lower (p<0.05) than C. Concentrations of total volatile fatty acids (VFAs) and propionic acid were higher (p<0.05) in the treatments than in C at 12 hr. Therefore, halogenated compounds (BCM, BES, BPS, CLF, and PMDI) inhibited in vitro methane emissions by inhibiting methanogens in the rumen. Further studies on safety are needed.

Effect of Roasted Ground Coffee Residue Extract on Shelf-life and Quality of Salted Mackerel (커피박 추출물이 간고등어의 저장성과 품질에 미치는 영향)

  • Song, Eu-Jin;Kim, Jin-Yul;Lee, So-Young;Kim, Koth-Bong-Woo-Ri;Kim, Seo-Jin;Yoon, So-Young;Lee, So-Jeong;Lee, Chung-Jo;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.6
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    • pp.780-786
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    • 2009
  • To develop a novel application for roasted ground coffee residue, hot water extract of roasted ground coffee residue was used in manufacturing salted mackerels. First, DPPH radical scavenging effect of roasted ground coffee residue extract was measured. As a result, roasted ground coffee residue extract showed high activity of about 92% in the concentration of 0.4 to 4 mg/mL. Thereafter, the salted mackerel was treated with 5, 10 and 15% of roasted ground coffee residue extract and its shelf-life and quality was investigated. The salted mackerels treated with 15% roasted ground coffee residue extract showed significantly low TBARS and VBN as compared to the control. In sensory evaluation, the salted mackerels treated with 10 and 15% roasted ground coffee residue extracts scored higher as compared to the control. In conclusion, roasted ground coffee residue extract increased the shelf-life of salted mackerel and improved the sensual quality by inhibiting lipid oxidation.

Physico.chemical Properties of Peatmoss and Coir Dust Currently Used as Root Medium Components for Crop Production in Korean Plant Factories (국내에서 식물공장용 배지 재료로 유통되는 피트모스와 코이어 더스트의 물리.화학적 특성)

  • Shin, Bo Kyoung;Son, Jung Eek;Choi, Jong Myung
    • Journal of Bio-Environment Control
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    • v.21 no.4
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    • pp.362-371
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    • 2012
  • Objective of this research was to secure the information on physical and chemical properties of peatmoss and coir dust. To achieve this, 6 kinds of peatmoss and 10 kinds of coir dust currently used in the country as the root medium components in plant factories were collected and analysed. The mean ${\pm}$ standard deviation (SD) of total porosity and container capacity in peatmoss and coir dust were $79.6{\pm}5.04$ and $83.6{\pm}6.18%$, and $69.9{\pm}10.17$ and $65.9{\pm}3.46%$, respectively. These indicate that peatmoss has higher water holding capacity than coir dust and the characteristics are highly varied among peatmoss. The 4 out of 5 kinds of peatmoss had lower than 10%, but coir dust had 12~26%, of air-filled porosity. The percentage of easily available water and buffering water in peatmoss and coir dust was 18~22 and 11~16% and 9~13 and 5.5~7.5%, respectively. These results indicate that precise irrigation is required when coir dust is used as the root medium. The ranges of pH and electrical conductivity (EC) were 3.46~4.17 and $0.137{\sim}0.253dS{\cdot}m^{-1}$ in peatmoss and 5.31~6.48 and $0.250{\sim}0.1.580dS{\cdot}m^{-1}$ in coir dust. However, $0.563{\pm}0.83dS{\cdot}m^{-1}$ in mean ${\pm}$SD of coir dust EC indicates that it is higher than that of peatmoss, and the coir dust are highly varied in EC. The cation exchange capacity of peatmoss was 3 to 4 times as high as that of coir dust. The coir dust had higher $NO_3$ and $PO_4$ and lower $NH_4$ than peatmoss. The K and Na concentrations in coir dust were extremely high indicating that these ions caused the rising in EC. The percentage of hot water and alkali extracts of peatmoss were 6.67~16.37 and 0~38%, whereas those of coir dust were 30.0~65.1 and 23.1~70.3%. These results mean that possible existence of growth inhibiting materials in coir dust.

The Haptic Perception Aspect shown in Landscape Architecture before Modernism - Focused on Historical Development Process - (모더니즘 이전 조경에 나타난 촉지적 지각 양상 - 역사적 전개 과정을 중심으로 -)

  • Kim, Jin-Seob;Kim, Jin-Seon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.4
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    • pp.1-14
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    • 2015
  • In the West, of the body's five senses sight is considered the most important but Ocular-centralistic thinking contains many issues. Privileging the subject and inhibiting interaction with the other senses, Ocular-centrism limits the experience of the world to the visual area. However, experiences can be understood as 'touching' various forms and are related to touch. With the heightened interest in the multi-sensuous side of the body contrary to Ocular-centrism, the intervention of the body in the external space has become an important issue in modern landscape architecture. This study explores the possibility of the haptic perception system that causes the active experience of a subject. Haptic perception plays a catalytic role leading an active experience of the subject and the subject experiences a sense of place through such haptic perception. By revealing what was known through the sense of touch through the concurrency and interaction of the various senses, haptic perception draws active participation The haptic perception system has been studied in various fields but has not been studied in the field of landscape architecture. Thus, this study discusses the aspect of haptic perception limited to landscape architecture shown before modernism. In a discussion on haptic perception, the concept of haptic perception is clarified through previous study reviews and literature and the characteristics of haptic perception are derived. Then, the problems of the Ocular-centrism system and the need for haptic perception are discussed. In the historical development process of haptic perception, the change process of the scopic regime is examined chronologically and the ways in which Ocular-centralistic thinking and anti-Ocular-centralistic thinking have been projected on the architecture and landscape architecture of each age are studied via literature and cases studies. The impact of the scopic regime on the landscape architecture field in the historical change process is examined.

Antioxidant and Inhibitory Effects of Korean Panax ginseng Extract on Pro-inflammatory Mediators in LPS-stimulated RAW264.7 Macrophages (산양삼(Korean Panax ginseng) 추출물의 항산화 효과 및 LPS로 염증이 활성화된 RAW 264.7 대식세포에서의 염증매개물질 억제효과)

  • Kim, Ye-Jin;Son, Dae-Yeul
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.10
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    • pp.1371-1377
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    • 2012
  • Biological activities of Korean Panax ginseng 55% ethanol extract (KPGE) were investigated. The measured total polyphenol content of KPGE was 357.45 mg/100 g. KPGE showed the highest ${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) radical scavenging activities of 80% and 86% at 1,000 ${\mu}g/mL$, respectively. DPPH and ABTS radical scavenging activities significantly increased in a KPGE concentration-dependent manner. SOD-like activity of KPGE (1, 10, and 100 ${\mu}g/mL$) increased from 22% up to 33% at KPGE concentrations of 500 and 1,000 ${\mu}g/mL$. KPGE treatment significantly suppressed the generation of pro-inflammatory mediators, including nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), and cytokines (tumor necrosis factor-alpha: TNF-${\alpha}$, interleukin-6: IL-6, interleukin-$1{\beta}$: IL-$1{\beta}$), in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. KPGE demonstrated strong anti-inflammatory activity that reduced NO and $PGE_2$ production in LPS-stimulated RAW 264.7 cells. Even low concentrations of KPGE (1 and 10 ${\mu}g/mL$) reduced $PGE_2$ and NO production in RAW 264.7 macrophages without LPS-stimulation, respectively. At concentrations of 100, 500, and 1,000 ${\mu}g/mL$, TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 production were significantly suppressed. The results of our study suggest the potential of Korean Panax ginseng as an excellent antioxidant substance for inhibiting inflammatory mediators. Therefore, Korean Panax ginseng (KPGE) may be used as a therapeutic approach to various inflammatory diseases.

Caffeine treatment during in vitro maturation improves developmental competence of morphologically poor oocytes after somatic cell nuclear transfer in pigs (돼지 난자의 체외성숙에서 Caffeine 처리가 난자 성숙과 체세포 핵이식 배아의 체외발육에 미치는 영향)

  • Lee, Joohyeong;You, Jinyoung;Lee, Hanna;Shin, Hyeji;Lee, Geun-Shik;Lee, Seung Tae;Lee, Eunsong
    • Journal of Embryo Transfer
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    • v.32 no.3
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    • pp.131-138
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    • 2017
  • In most mammals, metaphase II (MII) oocytes having high maturation promoting factor (MPF) activity have been considered as good oocytes and then used for assisted reproductive technologies including somatic cell nuclear transfer (SCNT). Caffeine increases MPF activity in mammalian oocytes by inhibiting p34cdc2 phosphorylation. The objective of this study was to investigate the effects of caffeine treatment during in vitro maturation (IVM) on oocyte maturation and embryonic development after SCNT in pigs. To this end, morphologically good (MGCOCs) and poor oocytes (MPCOCs) based on the thickness of cumulus cell layer were untreated or treated with 2.5 mM caffeine during 22-42, 34-42, or 38-42 h of IVM according to the experimental design. Caffeine treatment for 20 h during 22-42 h of IVM significantly inhibited nuclear maturation compared to no treatment. Blastocyst formation of SCNT embryos was not influenced by the caffeine treatment during 38-42 h of IVM in MGCOCs (41.1-42.1%) but was significantly improved in MPCOCs compared to no treatment (43.4 vs. 30.1%, P<0.05). No significant effects of caffeine treatment was observed in embryo cleavage (78.7-88.0%) and mean cell number in blastocyst (38.7-43.5 cells). The MPF activity of MII oocytes in terms of p34cdc2 kinase activity was not influenced by the caffeine treatment in MGCOCs (160.4 vs. 194.3 pg/ml) but significantly increased in MPCOCs (133.9 vs. 204.8 pg/ml). Our results demonstrate that caffeine treatment during 38-42 h of IVM improves developmental competence of SCNT embryos derived from MPCOCs by influencing cytoplasmic maturation including increased MPF activity in IVM oocytes in pigs.

Antifungal effects of synthetic human β-defensin 3-C15 peptide

  • Lim, Sang-Min;Ahn, Ki-Bum;Kim, Christine;Kum, Jong-Won;Perinpanayagam, Hiran;Gu, Yu;Yoo, Yeon-Jee;Chang, Seok Woo;Han, Seung Hyun;Shon, Won-Jun;Lee, Woocheol;Baek, Seung-Ho;Zhu, Qiang;Kum, Kee-Yeon
    • Restorative Dentistry and Endodontics
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    • v.41 no.2
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    • pp.91-97
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    • 2016
  • Objectives: The purpose of this ex vivo study was to compare the antifungal activity of a synthetic peptide consisting of 15 amino acids at the C-terminus of human ${\beta}$-defensin 3 (HBD3-C15) with calcium hydroxide (CH) and Nystatin (Nys) against Candida albicans (C. albicans) biofilm. Materials and Methods: C. albicans were grown on cover glass bottom dishes or human dentin disks for 48 hr, and then treated with HBD3-C15 (0, 12.5, 25, 50, 100, 150, 200, and $300{\mu}g/mL$), CH ($100{\mu}g/mL$), and Nys ($20{\mu}g/mL$) for 7 days at $37^{\circ}C$. On cover glass, live and dead cells in the biomass were measured by the FilmTracer Biofilm viability assay, and observed by confocal laser scanning microscopy (CLSM). On dentin, normal, diminished and ruptured cells were observed by field-emission scanning electron microscopy (FE-SEM). The results were subjected to a two-tailed t-test, a one way analysis variance and a post hoc test at a significance level of p = 0.05. Results: C. albicans survival on dentin was inhibited by HBD3-C15 in a dose-dependent manner. There were fewer aggregations of C. albicans in the groups of Nys and HBD3-C15 (${\geq}100{\mu}g/mL$). CLSM showed C. albicans survival was reduced by HBD3-C15 in a dose dependent manner. Nys and HBD3-C15 (${\geq}100{\mu}g/mL$) showed significant fungicidal activity compared to CH group (p < 0.05). Conclusions: Synthetic HBD3-C15 peptide (${\geq}100{\mu}g/mL$) and Nys exhibited significantly higher antifungal activity than CH against C. albicans by inhibiting cell survival and biofilm.