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121.
Jae Woong Shim Seong Ho Jo Sang Doo Kim Ha Young Lee Jeanho Yun Yoe-Sik Bae 《Experimental & molecular medicine》2009,41(8):584-591
In this study, we observed that lysophosphatidylglycerol (LPG) completely inhibited a formyl peptide receptor like-1 (FPRL1) agonist (MMK-1)-stimulated chemotactic migration in human phagocytes, such as neutrophils and monocytes. LPG also dramatically inhibited IL-1β production by another FPRL1 agonist serum amyloid A (SAA) in human phagocytes. However, LPG itself induced intracellular calcium increase and superoxide anion production in human phagocytes. Keeping in mind that phagocytes migration and IL-1β production by FPRL1 are important for the induction of inflammatory response, our data suggest that LPG can be regarded as a useful material for the modulation of inflammatory response induced by FPRL1 activation. 相似文献
122.
Cheuk-Lam Ho Wai-Yeung Wong Bing Yao Lixiang Wang 《Journal of organometallic chemistry》2009,694(17):2735-1081
A series of cyclometalating platinum(II) complexes with substituted 9-arylcarbazolyl chromophores have been synthesized and characterized. These complexes are thermally stable and most of them have been characterized by X-ray crystallography. The phosphorescence emissions of the complexes are dominated by 3MLCT excited states. The excited state properties of these complexes can be modulated by varying the electronic characteristics of the cyclometalating ligands via substituent effects, thus allowing the emission to be tuned from bright green to yellow, orange and red light. The correlation between the functional properties of these metallophosphors and the results of density functional theory calculations was made. Because of the propensity of the electron-rich carbazolyl group to facilitate hole injection/transport, the presence of such moiety can increase the highest occupied molecular orbital levels and improve the charge balance in the resulting complexes relative to the parent platinum(II) phosphor with 2-phenylpyridine ligand. The solution-processed electrophosphorescent organic light-emitting diodes doped with these platinum-based phosphors have been fabricated which showed a maximum external quantum efficiency of 2.77% for the best device, corresponding to a power efficiency of 3.48 lm/W and a luminance efficiency of 8.49 cd/A. The present work enables the rational design of platinum-carbazolyl electrophosphors by synthetically tailoring the structure of carbazolylpyridine ring that can permit good color-tuning versatility suitable for multi-color display technology. 相似文献
123.
Kwong-Chak Cheung Ming-Him So Kam-Piu Ho Kam-Han Lee Zhong-Yuan Zhou 《Journal of organometallic chemistry》2009,694(17):2842-85
A dipyridylamine ligand with a pendant pyrrole (N-(3-N,N′-bis(2-pyridyl)propylamino)pyrrole, PPP) and its corresponding rhenium(I) complex, Re(CO)3(κ2-N,N-PPP)Cl, were synthesized. The structure of Re(CO)3(κ2-N,N-PPP)Cl was determined by X-ray crystallography. Electrochemical polymerization of the pyrrole moiety resulted in the immobilization of poly[Re(CO)3(κ2-N,N-PPP)Cl] film onto a glassy carbon electrode, which exhibited electrocatalytic activity for the reduction of CO2 to CO. 相似文献
124.
We report a method for the quantitative analysis of human serum leptin, which is a protein hormone associated with obesity, using a nanoarray protein chip based on a single-molecule sandwich immunoassay. The nanoarray patterning of a biotin-probe with a spot diameter of 150 nm on a self-assembled monolayer functionalized by MPTMS on a glass substrate was successfully accomplished using atomic force microscopy (AFM)-based dip-pen nanolithography (DPN). Unlabeled leptin protein molecules in human serum were detected based on the sandwich fluorescence immunoassay by total internal reflection fluorescence microscopy (TIRFM). The linear regression equation for leptin in the range of 100 zM-400 aM was determined to be y = 456.35x + 80,382 (R = 0.9901). The accuracy and sensitivity of the chip assay were clinically validated by comparing the leptin level in adult serum obtained by this method with those measured using the enzyme-linked immunosorbent assay (ELISA) performed with the same leptin standards and serum samples. In contrast to conventional ELISA techniques, the proposed chip methodology exhibited the advantages of ultra-sensitivity, a smaller sample volume and faster analysis time. 相似文献
125.
Mine Ince François Cardinali Jun‐Ho Yum M. Victoria Martínez‐Díaz Mohammad K. Nazeeruddin Michael Grätzel Tomás Torres 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(20):6343-6348
Zinc(II) phthalocyanine dyes that contain triarylamine‐terminated bisthiophene and hexylbisthiophene groups have been synthesized by a convergent approach by using carboxytriiodo–ZnPc as a precursor. Further transformation of the iodo groups by a Pd‐catalyzed reaction allowed easy preparation of further extended π‐conjugated carboxy–ZnPcs. These dyes have been used as sensitizers in dye‐sensitized solar cells, which exhibit a panchromatic response and moderate overall efficiencies. 相似文献
126.
127.
Min Keun Kim Tae Ho Kang Jungho Kim Hoon Kim Han Dae Yun 《Applied biochemistry and biotechnology》2012,168(7):1834-1848
This study was conducted to assess the gene duplication and diversification of tandem cellulase genes in thermophilic bacteria. The tandem cellulase genes cel5C and cel5D were cloned from Thermotoga maritima MSB8, and a survey of the thermophilic bacterial genome for tandem cel genes from the databases was carried out. A clone having 2.3?kb fragment from T. maritima MSB8 showed cellulase activity, which had two open reading frames in tandem (cel5C and cel5D). The cel5C gene has 954?bp, which encodes a protein of 317 amino acid residues with a signal peptide of 23 amino acids, and the other gene cel5D consisting of 990?bp encoding a protein of 329 amino acid residues. These two proteins have similarity with the enzymes of glycosyl hydrolase family 5. From the enzyme assay, it was observed that Cel5C was extracellular and Cel5D was intracellular cellulase. Phylogenetic and homology matrix analyses of DNA and protein sequences revealed that family 12 cellulase enzymes Cel12A and Cel12B displayed higher homology (>50?%), but Cel5C and Cel5D enzymes belong to family 5 displayed lower homology (<30?%). In addition, repeated and mirror sequences in tandem genes are supposed to show the existence of gene duplication and recombination. 相似文献
128.
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130.
Lee JM Min YJ Lee KB Jeon SG Na JG Ryu HJ 《Langmuir : the ACS journal of surfaces and colloids》2010,26(24):18788-18797
The awareness of symptoms of global warming and its seriousness urges the development of technologies to reduce greenhouse gas emissions. Carbon dioxide (CO(2)) is a representative greenhouse gas, and numerous methods to capture and storage CO(2) have been considered. Recently, the technology to remove high-temperature CO(2) by sorption has received lots of attention. In this study, hydrotalcite, which has been known to have CO(2) sorption capability at high temperature, was impregnated with K(2)CO(3) to enhance CO(2) sorption uptake, and the mechanism of CO(2) sorption enhancement on K(2)CO(3)-promoted hydrotalcite was investigated. Thermogravimetric analysis was used to measure equilibrium CO(2) sorption uptake and to estimate CO(2) sorption kinetics. The analyses based on N(2) gas physisorption, X-ray diffractometry, Fourier transform infrared spectrometry, Raman spectrometry, transmission electron microscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy were carried out to elucidate the characteristics of sorbents and the mechanism of enhanced CO(2) sorption. The equilibrium CO(2) sorption uptake on hydrotalcite could be increased up to 10 times by impregnation with K(2)CO(3), and there was an optimal amount of K(2)CO(3) for a maximum equilibrium CO(2) sorption uptake. In the K(2)CO(3)-promoted hydrotalcite, K(2)CO(3) was incorporated without changing the structure of hydrotalcite and it was thermally stabilized, resulting in the enhanced equilibrium CO(2) sorption uptake and fast CO(2) sorption kinetics. 相似文献