• Title/Summary/Keyword: $Tf_2O$

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Tissue Factor Inhibitory Sesquiterpene Glycoside from Eriobotrya japonica

  • Lee, Ming-Hong;Son, Yeon-Kyoung;Han, Yong-Nam
    • Archives of Pharmacal Research
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    • v.27 no.6
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    • pp.619-623
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    • 2004
  • Tissue factor (TF, tissue thromboplastin) is a membrane bound glycoprotein, which acceler-ates the blood clotting, activating both the intrinsic and the extrinsic pathways to serve as a cofactor for activated factor VII (Vila). The TF-factor Vila complex (TF/VIIa) proteolytically activates factors IX and X, which leads to the generation of thrombin and fibrin clots. In order to isolate TF inhibitors, by means of a bioassay-directed chromatographic separation technique, from the leaves of Eriobotrya japonica Lindley (Rosaceae), a known sesquiterpene glycoside (2) and ferulic acid (3) were isolated as inhibitors that were evaluated using a single-clotting assay method for determining TF activity. Another sesquiterpene glycoside (1) was also isolated but was inactive in the assay system. Compound 3 was yielded by alkaline hydrolysis of compound 2. The structures of compounds 1, 2, and 3 were identified by means of spectral analysis as $3-O-{\alph}-L-rhamnopyranosyl-(1{\rightarrow}4)-a-L-rhamnopyranosyl-(1{\rightarrow}2)-[{\alph}-L-rhamnopyrano-syl-(1{\rightarrow}6)]-{\beta}-D-glucopyranosyl nerolidol$ (1), $3-O-{\alph}-L-rhamnopyranosyl-(1{\rightarrow}4)-{\alph}-L-rhamnopyr-anosyl-(1{\rightarrow}2)-[{\alph}-L-(4-trans-feruloyl)-rhamnopyranosyl-(1{\rightarrow}6)]-{\beta}-D-glucopyranosyl$ nerolidol (2) and ferulic acid (3), respectively. Compounds 2 and 3 inhibited 50% of the TF activity at con-centrations of 2 and $369{\;}\mu\textrm{m}/TF$ units, respectively.

Improved Purification of Thermophilic FoF1-ATP Synthase c-Subunit Rings and Solid-State NMR Characterization of Them in Different Lipid Membranes

  • Bak, Suyeon;Kang, Su-Jin;Suzuki, Toshiharu;Yoshida, Masasuke;Fujiwara, Toshimichi;Akutsu, Hideo
    • Journal of the Korean Magnetic Resonance Society
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    • v.17 no.2
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    • pp.67-75
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    • 2013
  • ATP synthase produces ATP, a major energy source for metabolic processes in organisms, from ADP and inorganic phosphate in cellular membranes. ATP synthase is known as a rotary motor, in which the c-subunit ring functions as a rotor. In this work, we have tried to develop a more general preparation procedure of thermophilic $F_oc$-ring ($TF_oc$-ring) for NMR measurements. The expression of $TF_oF_1$ is easily affected by various experimental conditions such as temperature, shape and size of a flask, a volume of medium, and shaking rate of an incubator. Accordingly, we have tried to optimize the expression conditions of $TF_oF_1$. $TF_oc$-rings were purified from $TF_oF_1$ according to a reported method. We modified purification procedures to improve purity and yield of $TF_oc$. On top of them, we found a new combination of detergents for the purification at anion-exchange column chromatography. To examine the effect of lipid environments on the structure, the $TF_oc$-rings were reconstituted into two kinds of lipid bilayers, namely, saturated and unsaturated lipid ones. Then, we have compared characteristics of the $TF_oc$-ring structures in these membranes with solid-state NMR.

Solubility of Hydrogen Sulfide and Methane in Ionic Liquids: 1-Ethy-3-methylimidazolium Trifluoromethanesulfonate and 1-Butyl-1-methylpyrrolidinium Trifluoromethanesulfonate (1-Ethyl-3-methylimidazolium trifluoromethanesulfonate와 1-Butyl-1-methylpyrrolidinium trifluoromethanesulfonate 이온성 액체에 대한 황화수소와 메탄의 용해도)

  • Lee, Byung-Chul
    • Korean Chemical Engineering Research
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    • v.54 no.2
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    • pp.213-222
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    • 2016
  • Solubility data of hydrogen sulfide ($H_2S$) and methane ($CH_4$) in two kinds of ionic liquids with the same anion: 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([emim][TfO]) and 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate ([bmpyr][TfO]) are presented at pressures up to about 30 MPa and at temperatures between 303 K and 343 K. The gas solubilities in ionic liquids were determined by measuring the bubble point pressures of the gas + ionic liquid mixtures with various compositions at different temperatures using a high-pressure equilibrium apparatus equipped with a variable-volume view cell. The $H_2S$ solubilities in ionic liquid increased with the increase of pressure and decreased with the increase of temperature. On the other hand, the $CH_4$ solubilities in ionic liquid increased significantly with the increase of pressure, but there was little effect of temperature on the $CH_4$ solubility. For the ionic liquds [emim][TfO] and [bmpyr][TfO] with the same anion, the solubility of $H_2S$ as a molality basis was substantially similar, regardless of the temperature and pressure conditions as a molar concentration basis. Comparing the solubilities of $H_2S$ and $CH_4$ in the ionic liquid [emim][TfO], the solubilities of $H_2S$ were much greater than those of $CH_4$. For the same type of ionic liquid, the solubility data of $H_2S$ and $CH_4$ obtained in this study were compared to the solubility data of $CO_2$ from the literature. When compared at the same pressure and temperature conditions, the $CO_2$ solubility was in between the solubility of $H_2S$ and $CH_4$.

산화아연 압전 나노전력발전소자 기반 에너지 하베스팅

  • Kim, Sang-U
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.49-49
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    • 2010
  • Nanopiezotronics is an emerging area of nanotechnology with a variety of applications that include piezoelectric field-effect transistors and diodes, self-powered nanogenerators and biosystems, and wireless nano/biosensors. By exploiting coupled piezoelectric and semiconducting characteristics, it is possible for nanowires, nanobelts, or nanorods to generate rectifying current and potential under external mechanical energies such as body movement (handling, winding, pushing, and bending) and muscle stretching, vibrations (acoustic and ultrasonic waves), and hydraulic forces (body fluid and blood flow). Fully transparent, flexible (TF) nanogenerators that are operated by external mechanical forces will be presented. By controlling the density of the seed layer for ZnO nanorod growth, transparent ZnO nanorod arrays were grown on ITO/PES films, and a TF conductive electrode was stacked on the ZnO nanorods. The resulting integrated TF nanodevice (having transparency exceeding 70 %) generated a noticeable current when it was pushed by application of an external load. The output current density was clearly dependent on the force applied. Furthermore, the output current density depended strongly on the morphology and the work function of the top electrode. ZnO nanorod-based nanogenerators with a PdAu, ITO, CNT, and graphene top electrodes gave output current densities of approximately $1-10\;uA/cm^2$ at a load of 0.9 kgf. Our results suggest that our TF nanogenerators are suitable for self-powered TF device applications such as flexible self-powered touch sensors, wearable artificial skins, fully rollable display mobile devices, and battery supplements for wearable cellular phones.

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Inhibitory Activity of Edible Mushrooms on the Tissue Thromboplastin (Tissue Factor) (조직 혈액응고인자에 대한 식용버섯류의 저해활성)

  • Hwang, Keum-Hee;Kim, Hyun-Ku;Han, Yong-Nam
    • Korean Journal of Food Science and Technology
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    • v.29 no.1
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    • pp.161-166
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    • 1997
  • Tissue thromboplastin (tissue factor), a membrane bound glycoprotein is an important initiating factor in blood coagulation cascade, which leads to the formation of thrombin by activating both factor X and IX. Activation of blood coagulation by TF is essential for blood injury, and stimulates the blood coagulation in myocardial infarction, cancer and blood coagulatory diseases. High density lipoprotein, apolipoprotein A-II were known to be biological TF inhibitors. Recently, studies on search for TF inhibitors from natural products have been active in Korea. Among the edible mushrooms screened for inhibitory activities on the TF, Lentinus edodes showed the most strong activity, followd by Agaricus bisporus and Ganoderma lucidium. And the fractionation of the above mushrooms with the chloroform ($CHCl_3$) and ethylacetate (EtOAc) was done and evaluated for the inhibitory activities on TF. In Ganoderma lucidium, $CHCl_3$ fraction and $H_2O$ layer were not active, but EtOAc fraction exhibited a strong inhibitory activity on TF and the $IC_{50}$ value was $1.07{\times}10^{-4}\;g$. In the case of Agaricus bisporus, there were no inhibitory activities on the TF in all of the fractions. $CHCl_3$ fraction and $H_2O$ layer of Lentinus edodes did not show inhibition on the TF but EtOAc fraction showed strong inhibition on the TF, and the $IC_{50}$ value was $7.70{\times}10^{-4}\;g$.

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The Effect of $WO_3$ Addition on Microwave Dielectric Properties in $BaTiO_3-3{(1-x)TiO_2-xWO_3}$ System ($WO_3$ 첨가량 변화에 따른 $BaTiO_3-3{(1-x)TiO_2-xWO_3}$ 계의 고주파 유전특성)

  • 박찬식;변재동;김왕섭;김경용
    • Journal of the Korean Ceramic Society
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    • v.32 no.4
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    • pp.448-454
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    • 1995
  • The effect of WO3 addition on microwave dielectric properties of BaTiO3-3{(1-x)TiO2-xWO3} system was studied. Addition of WO3 to this system resulted in the formation of BaWO4 and Ba2Ti9O20 phases. Both the dielectric constant (K) and the temperature coefficientof resonant frequency (Tf) were decreased with the amount of WO3 addition. The value of Q$\times$f0 was increased as the amount of WO3 was increased up to x=0.0275, and then decreased when x exceeded 0.03. At x=0.0275, this ceramic showed excellent microwave proprties of K=34-35, Q$\times$f0=50,000-53,000, and near zero ppm/$^{\circ}C$ of Tf.

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Characteristics of Soil Groups Basd on the Development of Root Rot of Ginseng Seedlings (인삼 유묘 뿌리썩음병 진전에 따른 토양군별 특성)

  • 박규진;정후섭
    • Korean Journal Plant Pathology
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    • v.13 no.1
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    • pp.46-56
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    • 1997
  • Based on the principal component analysis (PCA) of Richards' parameter estimates, ginseng field soils were grouped as the principal component 1 (PC1) and the principal component 2 (PC2). The microflora and physico-chemical characteristics of each soil group were compared to elucidate soil environmental factors affecting the disease development of root rot of ginseng seedling. Among 3 soil groups by PC1, there were differences in the populations of total fungi (TF) and Cylindrocarpon plus Fusarium (C+F), and the population ratio of Cylindrocarpon plus Fusarium to total fungi or total bacteria (C+F/TF, C+F/TB) in rhizoplane of ginseng seedlings, the population of total actinomycetes (TA) and the population ratio of total Fusarium to total actinomycetes (Fus/TA) in soil, and soil chemical properties (EC, NO3-N, K, Mn, ect.). Among 4 soil groups by PC2, there were differences in TF, C+F, TB, C+F/TF and C+F/TB in the rhizoplane, Trichoderma plus Gliocladium (T+G) in soil, and P2O5 content in soil. Especially, EC, NO3-N, K, K/Mg and Mn were positively correlated to PC1, and TA was negatively to PC1; however, TF, C+F, TB, C+F/TF and C+F/TB in the rhizoplane were significantly correlated to PC2 positively. On the other hand, microbes in the rhizoplane were not significantly correlated to the stand-missing rate (SMR), although TA and Fe/Mn were negatively correlated, and pH and Ca were positively correlated to SMR.

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Expression of Bombyx mori Transferrin Gene in Response to Oxidative Stress or Microbes (미생물 및 산화적 스트레스에 의한 누에 트랜스페린 발현)

  • Yun, Eun-Young;Kwon, O-Yu;Hwang, Jae-Sam;Ahn, Mi-Young;Goo, Tae-Won
    • Journal of Life Science
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    • v.21 no.11
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    • pp.1607-1611
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    • 2011
  • To analyze the role of Bombyx mori transferrin (BmTf) in response to microbes or oxidative stress, we investigated the level of BmTf transcripts in B. mori treated with various microbes and oxidative stress inducers. BmTf mRNA was mainly expressed in the epidermis and fat in the bodies of B. mori injected with Escherichia coli, and up regulated in response to microbes such as bacteria, fungi, or viruses, but was hardly altered in response to oxidative stress inducers such as $H_2O_2$, Cu, or $FeCl_3$. We also confirmed that BmTf mRNA expression was increased in Bm5 cells treated with ERK, PLC, PKA, PI3K, MAPK, or JNK inhibitors, respectively. To identify the major inducer of BmTf expression, we analyzed the amount of serum iron in the hemolymph of B. mori after injection or feeding with E. coli or $FeCl_3$. The results showed that the amount of serum iron was not changed by injection and feeding with E. coli, although BmTf mRNA was increased by injection with E. coli. On the contrary, injection and feeding with $FeCl_3$ significantly increased the amount of serum iron, although they did not alter the BmTf mRNA level. On the basis of these results, we assume that up-regulation of BmTf in B. mori is closely related to the defense of microorganism, and BmTf may be expressed at the basal constitutive level when it plays a role in iron metabolism by maintaining iron homeostasis and in the insect defense mechanism against oxidative stress.

Immunoradiometric Assay using Monoclonal Antibody Against Human Serum Transferrin Receptor for Diagnosis of Iron Deficiency (사람 혈청 트란스페린수용체의 단클론 항체를 이용한 방사면역측정과 철영양상태의 진단)

  • 김승렬
    • Journal of Nutrition and Health
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    • v.29 no.9
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    • pp.971-980
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    • 1996
  • The soluble transferrin receptor(TfR) in human serum has been shown recently to be a truncated form of intact membrane bound receptor containing most of the extracellular domain. We purfied the transferin-free TfR from human serum by immounoaffinity chromatography which produced the single protein identity in high resolution gel chormatography. The monoclonal antibodies(MAb) against purifed serum TfR were produced by fusion of spleen cells o fimmunized Balb/c mice and SP2 cells. Ten hybrids producing MAb specific for serum TfR were identifed and determine their iostypes. A immunoraddiometric assay (IRMA) for serum TfR was established using two monoclonal IgG1 antibodies as the coating and indicator antibodies on the bosis of their suitability in sandwich IRMA of serum TfR. The mean serum TfR levels in the 15 normal male, 15 normal female, and 19 iron-deficient subjects were 5.4$\pm$0.98, 4.6$\pm$0/76, and 18.0$\pm$12.8mg/1, respectively, and the difference in mean values between normal and iron deficient subjects was significant(p=0.0005). There existed the inverse logarithmic relationship(r=-0.9336, p<0.0001) between the serum TfR and ferritin levels.

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