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61.
Se-Jung Yoon Young Won Yoon Byoung Kwon Lee Hyuck Moon Kwon Ki-Chul Hwang Myunghyun Kim Woochul Chang Bum-Kee Hong Young-Ho Lee Soon-Jung Park Pil-Ki Min Se-Joong Rim 《Experimental & molecular medicine》2009,41(11):802-811
Advanced glycation endproducts (AGEs)-induced vascular smooth muscle cell (VSMCs) proliferation and formation of reactive oxygen species (ROS) are emerging as one of the important mechanisms of diabetic vasculopathy but little is known about the antioxidative action of HMG CoA reductase inhibitor (statin) on AGEs. We hypothesized that statin might reduce AGEs-induced intracellular ROS of VSMCs and analyzed the possible mechanism of action of statin in AGEs-induced cellular signaling. Aortic smooth muscle cell of Sprague-Dawley rat (RASMC) culture was done using the different levels of AGEs stimulation in the presence or absence of statin. The proliferation of RASMC, ROS formation and cellular signaling was evaluated and neointimal formation after balloon injury in diabetic rats was analyzed. Increasing concentration of AGEs stimulation was associated with increased RASMC proliferation and increased ROS formation and they were decreased with statin in a dose-dependent manner. Increased NF-κB p65, phosphorylated ERK, phosphorylated p38 MAPK, cyclooxygenase-2, and c-jun by AGEs stimulation were noted and their expression was inhibited by statin. Neointimal formation after balloon injury was much thicker in diabetic rats than the sham-treated group but less neointimal growth was observed in those treated with statin after balloon injury. Increased ROS formation, subsequent activation of MAPK system and increased VSMC proliferation may be possible mechanisms of diabetic vasculopathy induced by AGEs and statin may play a key role in the treatment of AGEs-induced diabetic atherosclerosis. 相似文献
62.
We investigated structures, vibrational frequencies, and rotational barriers of disilane (Si2H6), hexafluorodisilane (Si2F6), and hexamethyldisilane (Si2Me6) by using ab initio molecular orbital and density functional theories. We employed four different levels of theories (i.e., HF/6–31G*, MP2/6–31G*, BLYP/6–31G*, and B3LYP/6–31G*) to optimize the structures and to calculate the vibrational frequencies (except for Si2Me6 at MP2/6–31G*). MP2/6–31G* calculations reproduce experimental bond lengths well, while BLYP/6–31G* calculations largely overestimate some bond lengths. Vibrational frequencies from density functional theories (BLYP/6–31G* and B3LYP/6–31G*) were in reasonably good agreement with experimental values without employing additional correction factors. We calculated the ΔG‡(298 K) values of the internal rotation by correcting zero-point vibration energies, thermal vibration energies, and entropies. We performed CISD/6–31G*//MP2/6–31G* calculations and found the ΔG‡(298 K) values for the internal rotation of Si2H6, Si2F6, and Si2Me6 to be 1.36, 2.06, and 2.69 kcal/mol, respectively. The performance of this level was verified by using G2 and G2(MP2) methods in Si2H6. According to our theoretical results, the ΔG‡(298 K) values were marginally greater than the ΔE‡(0 K) values in Si2F6 and Si2Me6 due to the contribution of the entropy. In Si2H6 the ΔE‡(0 K) and ΔG‡(298 K) values were coincidently similar due to a cancellation of two opposing contributions between zero-point and thermal vibrational energies, and entropies. Our calculated ΔG‡(298 K) values were in good agreement with experimental values published recently. In addition, we also performed MM3 calculations on Si2H6 and Si2Me6. MM3 calculated rotational barriers and thermodynamic properties were compared with high level ab initio results. Based on this comparison, MM3 calculations reproduced high level ab initio results in rotational barriers and thermodynamic properties of Si2H6 derivatives including vibrational energies and entropies, although large errors exist in some vibrational frequencies. © 1997 John Wiley & Sons, Inc. J Comput Chem 18 : 1523–1533, 1997 相似文献
63.
The essential oil of the needles of Pinus canariensis, cultivated in the Algiers region (Algeria), was obtained by hydrodistillation in a yield of 0.3% and analyzed by capillary GC and GC/MS. More than 46 compounds were identified amounting to ca 92.6% of the total oil. The more important constituents were β-selinene (63.7%), β-caryophyllene (9.9%), and limonene (3.5%).__________Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 134–135, March–April, 2005. 相似文献
64.
Investigations have been carried out in order to give new insights into the real structure of two alkaloids isolated from the Nitraria genus namely nitraraine and nitraraidine. Closely related tangutorine is put forward as a plausible alternative to the structure proposed so far for nitraraine. 相似文献
65.
On the Bergman space of the unit ball of Cn, we study the finite rank problem for Toeplitz products with harmonic symbols. We first solve the problem with two factors in case symbols have local continuous extension property up to the boundary. Also, in case symbols have additional Lipschitz continuity up to (some part of) the boundary, we solve the problem for multiple products with number of factors depending on the dimension n. Analogous theorems on the polydisk are also obtained. 相似文献
66.
67.
A cholesterol derivative forms self-assembled helical ribbons in organic solvent, and treatment of this helical ribbon lipid as a template with Pd(Ac)2 provides helically-patterned arrays of palladium nanoparticles followed by reduction. 相似文献
68.
We study resonance patterns of a spiral-shaped dielectric microcavity with chaotic ray dynamics. Many resonance patterns of this microcavity, with refractive indices n=2 and 3, exhibit strong localization of simple geometric shape, and we call them quasiscarred resonances in the sense that there is, unlike conventional scarring, no underlying periodic orbits. It is shown that the formation of a quasiscarred pattern can be understood in terms of ray dynamical probability distributions and wave properties like uncertainty and interference. 相似文献
69.
The compact differences of composition operators acting on the weighted L 2-Bergman space over the unit disk is characterized by the angular derivative cancellation property and due to Moorhouse. In this paper we extend Moorhouse’s characterization, as well as some related results, to the ball and, at the same time, to the weighted L p -Bergman space for the full range of p. 相似文献
70.
El Montassir Dahmane Nadia Eladlani Mohammed Rhazi 《International Journal of Polymer Analysis and Characterization》2014,19(4):342-351
The contents of the exoskeleton of Parapenaeus longirostris from Moroccan local sources were analyzed and the percentages of inorganic salt, protein, lipid, and chitin were determined. Chitin in the α form was extracted from Parapenaeus longirostris shells by 0.25 M HCl and 1 M NaOH treatment for demineralization and deproteinization, respectively. The obtained chitin was converted into the more useful soluble chitosan. The chemical structure and physico-chemical properties of chitin and chitosan were characterized using Fourier transform-infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, X-ray diffractometry (XRD), and scanning electron microscopy (SEM). The molecular weight (MW) of chitosan was determined by viscometric methods. The degree of acetylation (DA) of chitin and chitosan was determined by the 1H NMR technique. To the best of our knowledge this is the first report on the extraction and characterization of chitin and chitosan from Parapenaeus longirostris. 相似文献