• Title/Summary/Keyword: $D_{50}$

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Recovery from the Two-generation Reproductive Toxicity in Sprague-Dawley Rats by Treatment with Decursin and Decursinol Angelate (Decursin and decursinol angelate가 2세대 출산률 회복에 미치는 영향)

  • Kim, Kang Min;Ok, Seon;Go, Youn Suk;Kang, Jae Seon
    • Journal of Life Science
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    • v.25 no.7
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    • pp.765-772
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    • 2015
  • The aim of this study was to determine the effect of decursin (D) and decursinol angelate (DA) against bisphenol A (BPA) toxicity in a rat two-generation study. Adult rats were divided into the following three groups: (1) control, (2) BPA, and (3) BPA+D/DA. The D and DA treatment of F0 parents increased the terminal body weight and relative adult organ weights (testes, kidneys, spleen, and liver) when compared with the BPA group. A significant decrease in sperm count was found in the BPA+D/DA (7.69%) and BPA (64.70%, p<0.01) groups, when compared with the sperm count in the control group. No offspring were obtained in the F1 generation of the BPA (50 mg/kg/day) group, but the addition of D/DA in the BPA+D/DA group significantly restored fertility (55.78%) and gestation indices (98.87%) in the F1 generation. No significant differences were found in the fertility index between the control (75.02%) and the BPA+D/DA (78.11%) groups in the two-generation study, when compared with the one-generation study. The viability ratio during lactation in the D/DA group was also similar to that of the control group. These data indicate that D/DA (50 mg/kg/day) administered over two generations causes significant positive changes in reproductive or developmental parameters.

Studies on the Chemical Control of White-tip Nematode, Aphelenchoides besseyi Christie, before Transplanting (모내기전 벼이삭선충(Aphelenchoides besseyi Christie)의 약제방제에 관한 연구)

  • Lee Y. B.;Park J. S.;Han S. C.
    • Korean journal of applied entomology
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    • v.11 no.1
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    • pp.37-40
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    • 1972
  • Experiments were carried out to control white-tip nematode, Aphelenchoides besseyi Christie, during the period just before transplanting. The experimental results were summarized as fellows: 1: From a 12-hr to a 24-hr sled-soaking application into 500 times dilutions of Malathion $80\%$ Ec, Sumithion $50\%$ EC and Lebaycid $50\%$ EC were highly effective than other emulsifierble concentrations of chemicals. 2) The water surface application of PSP-204 $5\%$ G, Diazinon $3\%$ G, Nemagon $20\%$ G and Terracurr-P $5\%$ G were effective. 3: Root·dipping application of Sumithion $50\%$ Ec, Lebaycid $50\%$ Ec and Nemagon $80\%$ Ec were more effective chemicals than others.

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A Fibrinolytic Enzyme from Bacillus amyloliquefaciens D4-7 Isolated from Chungkook-Jang; It′s Characterization and Influence of Additives on Thermostability. (청국장으로부터 분리한 Bacillus amyloliquefaciens D4-7이 분비하는 혈전용해효소의 특성 및 열안정성에 미치는 첨가물의 효과)

  • 김상숙;이주훈;안용선;김정환;강대경
    • Microbiology and Biotechnology Letters
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    • v.31 no.3
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    • pp.271-276
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    • 2003
  • Bacillus amyloliquefaciens D4, which produces a strongly fibrinolytic enzyme, was isolated from Chungkook-Jang, a traditional Korean soybean-fermented food. B. amyloliquefaciens D4 was mutated with N-methyl-N-nitro-N-nitrosoguanidine (MNNG) to yield a series of mutants with increasing levels of fibrinolytic enzyme production. After mutation, a mutant D4-7 was obtained with fibrinolytic activity about eight times stronger than the parent strain. The fibrinolytic activity of B. amyloliquefaciens D4-7, reached a maximum, when the producer was cultivated in 2% Isolated Soy Protein (ISP) broth for 48 h at $37^{\circ}C$. Compared to commercial fibrinolytic enzymes, the cell-free culture supernatant of B. amyloliquefaciens D4-7 showed stronger activity than plasmin and streptokinase. The optimum temperature and pH were $50^{\circ}C$ and 10.0 and thermostability was increased by the addition of glycerol, glucose, and NaCl.

Clinical Study on Tendency of Addition Power with Age (연령별 노안 가입도 경향에 관한 임상적 연구)

  • Kim, Mi-Yeon;Kim, Jae-Gwang;Kim, Tae-Hun;Sung, A-Young
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.2
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    • pp.131-135
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    • 2006
  • The purposes of this study is examining a wearing tendency of a progressive multifocal lens. We measured refractive error values using subjective and objective refraction method with subjects in 40-65 ages. Also, we investigated and analyzed distribution of addition power and wearing tendency of progressive multifocal lens. Detected addition powers were ranged of +0.75D - +3.00D. In case of average addition, they were detected with +1.18D in 40's, +1.55D - +1.97D in 50's and +2.38D in above 61's age. The distributions of visual ability at a distant were measured that the hyperopia and hyperopic astigmatism 43%, the myopia and myopic astigmatism characteristic astigmatism 7% appeared highly with 36%. The male who uses the interior aspect multi focal lens with the short-range work were appeared the male 20%, the woman 19%.

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Broadband Active RF Attenuator with Maximun Attenuation of -110dBm (최대 -110dBm 감쇄기능을 제공하는 능동형 광대역 RF 감쇄기)

  • Paik, Junghoon
    • Journal of Broadcast Engineering
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    • v.22 no.5
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    • pp.665-670
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    • 2017
  • In this paper, we propose an implementation technology for an active attenuator with the maximum attenuation of -110dBm in the frequency band of 50MHz to 2,15GHz. It provides USB interface to connect to PC providing GUI that sets signal frequency and attenuation step of minimum 1dB. As it attenuates the input signal level down to -110dBm, circuit and equipment design technologies are applied to control both internal and external electro-magnetic noises.. Through the performance test, it is assured that it attenuates input signal level down to -110dBm for the input signal levels of -10 to -30dBm.

A PROMISING NEW ANTI-WRINKLE INGREDIENT: Pericarpium castaneae extracts

  • Kim, Beom-Jun;Jo, Byoung-Kee;Kim, Jeong-Ha
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.25 no.4 s.34
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    • pp.57-63
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    • 1999
  • Pericarpium castaneae extracts have variously potent activities, such as anti-oxidative activity and free radical scavenging activity. in vivo and in vitro studies both indicate that pericarpium castaneae extracts acts as a free radical scavenger($IC_{50}:7.6{\mu}g/ml$) stronger than gallic acid($IC_{50}:12.5{\mu}g/ml$) and ellagic acid($IC_{50}:15{\mu}g/ml$) which could prevent cutaneous UV damages and skin aging. The extracts showed a good effect as a anti-oxidant($IC_{50}:50{\mu}g/ml$). It was shown that the appearance of wrinkle in human skin was reduced by topical application of pericarpium castaneae extracts. And the treatment of human skin with the extracts increased the elasticity and moisture of the skin. We investigated the effect of the pericarpium castaneae extracts on production of extracellular matrix using cultured A431 fibroblast cells. The results indicated that the extracts had no detectable effect on collagen synthesis. But synthesis of cell adhesion protein was increased by the extracts. The results suggest that increase of cell adhesion protein synthesis by pericarpium castaneae extracts has closely related to reduction of wrinkle in skin.

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A PROMISING NEW ANTI-WRINKLE INGREDIENT : Pericarpium castaneae extracts

  • Kim, Beom-Jun;Jo, Byoung-Kee;Kim, Jeong-Ha
    • Proceedings of the SCSK Conference
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    • 1999.10a
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    • pp.57-64
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    • 1999
  • Pericarpium castaneae extracts have variously potent activities, such as anti-oxidative activity and free radical scavenging activity. in vivo and in vivo studies both indicate that pericarpium castaneae extracts acts as a flee radical scavenger ($IC_{50}$/: 7.6$\mu\textrm{g}$/ml) stronger than gallic acid($IC_{50}$/: 12.5$\mu\textrm{g}$/ml) and ellagic acid($IC_{50}$/: 15$\mu\textrm{g}$/ml) which could prevent cutaneous UV damages and skin aging. The extracts showed a good effect as a anti-oxidant ($IC_{50}$/: 50$\mu\textrm{g}$/ml). It was shown that the appearance of wrinkle in human skin was reduced by topical application of pericarpium castaneae extracts. And the treatment of human skin with the extracts increased the elasticity and moisture of the skin. We investigated the effect of tile pericarpium castaneae extracts on production of extracellular matrix using cultured A431 fibroblast cells. The results indicated that the extracts had no detectable effect on collagen synthesis, But synthesis of cell adhesion protein was increased by the extracts. The results suggest that increase of cell adhesion protein synthesis by pericarpium castaneae extracts has closely related to reduction of wrinkle in skin.

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Antioxidative and Cellular Protective Effects of Dolwoe (Gynostemma pentaphyllum Makino) Extracts against Oxidative Stress (돌외(Gynostemma pentaphyllum Makino) 추출물의 산화적 스트레스에 대한 항산화 및 세포보호효과)

  • Kim, Kyoung Mi;Kim, A-Rang;Kim, A-Young;Ha, Ji Hun;Xuan, Song Hua;Jeong, Yoon Ju;Park, Young Min;Jeong, Hyo Jin;Hong, In Gi;Park, Soo Nam
    • Korean Journal of Pharmacognosy
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    • v.48 no.2
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    • pp.125-133
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    • 2017
  • In this study, we investigated the total phenolic and flavonoid contents, component analysis, antioxidative activity and cellular protective effects against oxidative stress on human skin cells in 50% ethanol extract, ethyl acetate fraction and aglycone fraction obtained from Gynostemma pentaphyllum (G. pentaphyllum) Makino. The DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activites ($FSC_{50}$) of the 50% ethanol extracts, ethyl acetate fraction and aglycone fraction were 246.8, 147.2, $128.9{\mu}g/mL$, respectively. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of the 50% ethanol extract, ethyl acetate fraction and aglycone fraction on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescence assay were 37.15, 10.74, $7.19{\mu}g/mL$, respectively. We investigated the cellular protective activity and the results showed that treatment of aglycone fraction ($0.05-0.39{\mu}g/mL$) protect human skin cells in a concentration-dependent manner when the skin cell damages were induced by treating them with $H_2O_2$. These results suggest that extract/fractions of G. pentaphyllum Makino may be applicable as natural antioxidants in cosmetics.

Antioxidant Activities and Cytoprotective Effects of Lonicera japonica Thunb. Extract and Fraction against Oxidative Stress (인동덩굴 추출물과 분획물의 항산화 활성 및 산화적 스트레스에 대한 세포 보호 효과)

  • Lee, Ye Seul;Yun, Mid Eum;Lee, Yun Ju;Park, Young Min;Lee, Sang Lae;Park, Soo Nam
    • Microbiology and Biotechnology Letters
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    • v.46 no.1
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    • pp.18-28
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    • 2018
  • In this study, the antioxidant activities and cytoprotective effects against oxidative stress of Lonicera japonica Thunb. 50% ethanol extract and ethyl acetate fraction were investigated. Using the 1,1-diphenyl-2-picrylhydrazyl assay, the free radical scavenging activity (FSC50) of L. japonica Thunb. 50% ethanol extract and ethyl acetate fraction was determined as 152.00 and $77.25{\mu}g/ml$, respectively. To measure the reactive oxygen species (ROS) scavenging activity, the total antioxidant capacity (OSC50) was determined by using a luminol-dependent chemiluminescence assay. The antioxidant activity of the ethyl acetate fraction ($0.33{\mu}g/ml$) was approximately four times stronger than that of the 50% ethanol extract ($1.12{\mu}g/ml$). The protective effect against $^1O_2$-induced cellular damage of human erythrocytes (${\tau}_{50}$) was 46.0 min at $10{\mu}g/ml$ of the 50% ethanol extract and 52.3 min at $1{\mu}g/ml$ of the ethyl acetate fraction. We also investigated the cytoprotective effects against oxidative stress induced by $H_2O_2$ and the intracellular ROS scavenging activity in response to UVB irradiation and found that the extract and fraction protected human skin cells from damage and reduced ROS. These results confirmed that L. japonica Thunb. was a valuable plant-derived natural antioxidant with potential for development as an antioxidative functional ingredient.

Comparison of on rat intestinal ${\alpha}-glucosidase$ activity and the chemical compositions of Korean and Chinese Schizandra chinensis

  • Chae, Hee-Jun;Lee, Min-Hu;Kim, Sun-Hyo;Moon, Hae-Yeon
    • 한국생물공학회:학술대회논문집
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    • 2005.04a
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    • pp.546-552
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    • 2005
  • The purpose of this study was to determine the effect of rat intestinal ${\alpha}-glucosidase$ inhibitor ; methanol(80%), ethanol(80%) and $dH_2O$ extract of Schizandra chinensis in Korea(KS : Schizandra chinensis in Korea) and China(CS : Schizandra chinensis in China). When the final concentration was 1 $mg/m{\ell}$ for each sample(KS and CS), MeOH extract of KS($IC_{50}$ 1.62 mg/ml) showed 46.8%, EtOH extract of KS($IC_{50}$ 1.48 mg/ml) showed 47.4%, $dH_2O$ extract of KS($IC_{50}$ 1.72 mg/ml) showed 46.3% and MeOH extract of CS($IC_{50}$ 8.35 mg/ml) showed 13.3%, EtOH extract of CS($IC_{50}$ 8.05 mg/ml) showed 16%, $dH_2O$ extract of CS($IC_{50}$ 8.37 mg/ml) showed 11.54% of inhibiter for p-nitrophenyl ${\alpha}$, D-glucopyranoside ${\alpha}-glcosidase$ activity, respectively, And the contents of total phenol, flavonoid of Schizandra chinensis were measured. When the final concentration was 1 $mg/m{\ell}$ for each sample(KS and CS), total phenol and flavonoid in KS were higher than CS, respectively.

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