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61.
Diabetes, a multifunctional disease and a major cause of morbidity and mortality in the industrialized countries, strongly associates with the development and progression of atherosclerosis. One of the consequences of high level of glucose in the blood circulation is glycation of long-lived proteins, such as collagen I, the most abundant component of the extracellular matrix (ECM) in the arterial wall. Glycation is a long-lasting process that involves the reaction between a carbonyl group of the sugar and an amino group of the protein, usually a lysine residue. This reaction generates an Amadori product that may evolve in advanced glycation end products (AGEs). AGEs, as reactive molecules, can provoke cross-linking of collagen I fibrils. Since binding of low-density lipoproteins (LDLs) to the ECM of the inner layer of the arterial wall, the intima, has been implicated to be involved in the onset of the development of an atherosclerotic plaque, collagen modifications, which can affect the affinity of native and oxidized LDL for collagen I, can promote the entrapment of LDLs in the intima and accelerate the progression of atherosclerosis.In this study, open tubular capillary electrochromatography is proposed as a new microreactor to study in situ glycation of collagen I. The kinetics of glycation was first investigated in a fused silica collagen I-coated capillary. Dimethyl sulphoxide, injected as an electroosmotic flow marker, gave information about the charge of coating. Native and oxidized LDL, and selected peptide fragments from apolipoprotein B-100, the protein covering LDL particles, were injected as marker compounds to clarify the interactions between LDLs and the glycated collagen I coating. The method proposed is simple and inexpensive, since only small amounts of collagen and LDL are required. Atomic force microscopy images complemented our studies, highlighting the difference between unmodified and glycated collagen I surfaces. 相似文献
62.
63.
The Fe100-xMox(13≤x≤25) alloy nanowire arrays are synthesized by electrodeposition of Fe 2+ and Mo 2+ with different ionic ratios into the anodic aluminum oxide templates.The crystals of Fe100-xMox alloy nanowires gradually change from polycrystalline phase to amorphous phase with the increase of the Mo content and the nanowires are of amorphous structure when the Mo content reaches 25 at%,which are revealed by the X-ray diffraction and the selected area electron diffraction patterns.As the Mo content increases,the magnetic hysteresis loops of Fe100-xMox alloy nanowires in parallel to the nanowire axis are not rectangular and the slopes of magnetic hysteresis loops increase.Those results indicate that the magnetostatic interactions between nanowires and the magnetocrystalline anisotropy both have significant influences on the magnetization reversal process of the nanowire arrays. 相似文献
64.
Palash SetuaRajib Pramanik Souravi SarkarChiranjib Ghatak Vishal Gobind RaoNilmoni Sarkar Satyen Kumar Das 《Journal of Molecular Liquids》2011,162(1):33-37
Two silver salts, silver tetrafluoroborate and silver trifluoromethanesulfonate were dissolved in two different room temperature ionic liquids (RTILs), 1-Butyl-3 methyl imidazolium tetrafluoroborate ([Bmim][BF4]) and 1-Butyl-1 methyl pyrrolidinium trifluoromethanesulfonate ([Bmpy][Tfms]). Triton x-100 (TX-100) surfactant and cyclohexane as nonpolar medium are used to dissolve these RTILs to create reverse micellar system. Pure reverse micellar system is characterized by dynamic light scattering (DLS) measurement. These pure RTIL reverse micellar systems are used to prepare stable silver nanoparticle solution without using any other auxiliary solvent in the whole process. 相似文献
65.
本文研究了两种不同系统因素影响下完全检验的质量最优问题 ,采用有两种不同控制界限的控制图来控制生产过程 ,并根据完全检验的特点 ,提出了一种新的最优模型。 Hui(1 991 )提出的最优模型是本文的最优模型的特殊情况 ,并且本文建立的最优模型还可推广到两种以上不同的系统因素下影响的情况 相似文献
66.
Iqbal Mahmud A.J.F. Samed Md. Anamul Haque Md. Abu Bin Hasan Susan 《Journal of Saudi Chemical Society》2011,15(3):203-208
Cyclic voltammetric behavior of anthraquinone in aqueous medium has been studied in presence of a non-ionic surfactant, Triton X-100 (TX-100) using sodium salt of anthraquinone-2-sulphonic acid (AQS) as the electro-active species. When cathodic potential is applied, the anthraquinone (AQ) group of AQS is reduced to its dianion. In the reverse scan, the oxidation of AQ2− gives AQ. The electrochemical behavior shows a profound influence from the dissolved state of TX-100 in aqueous media. Spectrophotometric results indicate interaction between AQ and TX-100. A CEC (chemical–electrochemical–chemical) mechanism with the electrochemical reaction coupled with preceding interaction of AQS with TX-100 and following protonation reaction of reduced AQ has been proposed. 相似文献
67.
The adsorption and phase formation of bromide on Ag(100) has been studied by chronocoulometry and surface X-ray scattering (SXS). With increasing electrode potential, bromide undergoes a phase transition from a lattice gas to an ordered c(2×2) structure (θ=0.5). The degree of lateral disorder was estimated by comparing the SXS- and the electrochemical measurements. Based on chronocoulometric experiments, a thermodynamic analysis of charge density data was performed to describe the bromide adsorption at the Ag(100) electrode. The Gibbs surfaces excess, electrosorption valencies, Esin–Markov coefficients, and the Gibbs energy of adsorption, lateral interaction energies as well as surface dipole moments have been estimated. The experimental θ versus E- isotherms are modeled employing (i) a quasi-chemical approximation as well as (ii) the results of a recent Monte Carlo simulation. An attempt is made to discuss the structure data and thermodynamic quantities of bromide adsorption on Ag(100) on the basis of the Grahame–Parsons model of the Helmholtz layer. 相似文献
68.
Eduardo Rodríguez de San Miguel Anel V. Garduño-García María E. Núñez-Gaytán Julio C. Aguilar Josefina de Gyves 《Journal of membrane science》2008
An organic–inorganic hybrid membrane was synthesized and evaluated for gold(III) transport from concentrated hydrochloric acid medium. The membrane was prepared by crosslinking of hydroxy terminated poly(dimethylsiloxane) with (3-aminopropyl) triethoxysilane in the presence of the commercial extractant Kelex 100. An optimization of the transport conditions was performed and selectivity with respect to copper(II) and zinc(II) determined. Around 70% of Au(III) was transported from an initially 10 ppm aqueous solution under optimized conditions with high selectivity towards 50 ppm of Cu(II) or 100 ppm of Zn(II) in 6 h. In addition the membrane extraction equilibrium reaction and its corresponding extraction equilibrium constant were evaluated and compared to those obtained in liquid–liquid solvent extraction. Membrane characterization was attained by ATR-FTIR spectroscopy. 相似文献
69.
Yingchao Liu Jinsong Wu Sixiu Liu Dongxiao Zhuang Yongfei Wang Xuefei Shou Jianhong Zhu 《Colloids and surfaces. B, Biointerfaces》2009,71(2):187-193
Laser capture microdissection (LCM) technology combined with immunohistochemistry (immuno-LCM) is a valuable tool to obtain specific target cell populations and therefore this technique enables more accurate proteomic profile. In this study, we optimized the regular immuno-LCM technique to isolate and stain pure prolactin cells from either normal human pituitary (n = 6) or prolactioma (n = 11). Compared with the routine procedure, more intense and specific staining could be obtained when sections were pretreated with 0.2% Triton X-100 for 4 min. Interestingly, longer pretreatment (0.2% Triton X-100 for 10 min) or higher concentration (2% Triton X-100 for 4 and 10 min) greatly impaired labeling intensity and cell shape. Further scanning electron microscope study revealed that the component extracted from the cell surface by Triton X-100 was lipid. Using the optimized immuno-LCM technique, more pure prolactin cells could be isolated and prepared for further proteomic analysis. Taken together, we reported an optimized immuno-LCM technique that could effectively dissect pure target cells in different type pituitary adenomas for further proteomics analysis. 相似文献
70.