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1.
Betulinic acid is one such natural pentacyclic triterpenoid compound, holding various pharmacological properties but its poor bioavailability is the only limitation. One of the biological macromolecules such as Lignin is a plant-derived aromatic, eco-friendly and low-cost polymer that certainly self-assembles into nano-sized colloids. Therefore, onto the current investigation, we increased the bioavailability of betulinic acid by coating on to a nanopolymer prepared with poly vinyl alcohol, lignins and methyl acrylate. Betulinic acid loaded polyvinyl alcohol/ethylacrylate grafted Lignin polymer (PVA/Lig-g-MA) nanoformulation was characterized using FTIR, XRD, SEM and TEM analysis and also the drug entrapment, in vitro drug releasing capacity was done to examine the efficiency of the nanoformulation of a drug. The MTT assay was evaluated the cytotoxicity of synthesized nanoformulation against normal endothelial cells HUVEC and HAPEC to confirm the side effects of the drug. The anti-atherosclerotic property of the nanoformulation was ascertained in both in vitro condition (with HUVEC and HPAEC) and in vivo studies (with Wistar rats). As a result, the characterization studies and in vitro studies clearly confirmed the Betulinic acid loaded PVA/Lig-g-MA nanoformulation is an ideal nanopolymer and it doesn’t cause any cytotoxic effect in normal endothelial cells. It also decreased the lipopolysaccharides induced inflammation through the down-regulation of NFκB and MAP/JNK signaling molecule expressions. Following in vivo results confirmed the synthesized nanoformulation effectively decreased the hyperchlostremia, inflammation and vasoconstriction, which induced over high fat diet. The results of histopathological analysis of cardiac tissues also confirmed the cardioprotective role of synthesized nanoformulation. Overall, both the in vitro and in vivo studies authentically proven the Betulinic acid loaded PVA/Lig-g-MA nanoformulation would be a potent cost effective anti-atherosclerotic nanodrug.  相似文献   
2.
A new organic-inorganic hybrid adduct, [HgI2(dps)] n (dps=4,4′-dipyridylsulfide), has been synthesized by the reaction of HgI2 with dps in THF at room temperature. The structure characterization was performed by means of IR, elemental analyses and single crystal X-ray analysis. It crystallizes in space group P2(1)/c with a=5.5522(1) ?, b=12.127(2) ?, c=21.508(4) ?, β=91.84(3)°. The structure consists of distorted tetrahedral Hg(II) centers bridged by dps ligands to form one-dimensional linear chains with C–H···I interaction. Comparison of transition metal assemblies with dps showed that the dimensionality and structure of self-assembled supramolecule depend on the coordination preferences of metal ions, the geometry, bulk, and rigidity of ligands, the number and size of anions, and the supramolecular weak interactions.Supplementary material Crystallographic data for the structure reported in this article has been deposited in the Cambridge Crystallographic Data Center, CCDC No. 285579 for compound 1. The information may be obtained free of charge from the Director, CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK (fax: +44-1223-336033; e-mail: deposit@ccdc.cam.ac.uk or http://www.ccdc.cam.ac.uk).  相似文献   
3.
Tris(hydroxymethyl)phosphine [P(CH2OH)3, THP] is demonstrated to be an alternative fixative to glutaraldehyde for preparation of proteinaceous specimens for SEM analysis. THP is easily prepared from commercially-available [P(CH2OH)4]Cl, and unlike many other alkylphosphines, is reasonably air-stable [>7 days at pH 7–8]. Experiments carried out with chicken breast muscle, cross-sectioned perpendicular to the muscle fibres and imaged using SEM, indicate that THP effectively fixes the muscle structure with minimal discolouration of the sample.  相似文献   
4.
沈丽丽  刘若雨  廖新成  叶勇 《化学研究》2010,21(5):40-43,47
在无溶剂条件下,以碳酸钾做催化剂,芳香醛与亚磷酸酯在室温下通过研磨,合成了一系列磷酸酯类化合物.该反应条件温和,操作简单,时间短,对环境友好,是一种绿色的合成方法.产物结构经IR,MS,1HNMR等方法表征.  相似文献   
5.
The Mei symmetries and the Lie symmetries for nonholonomic controllable mechanical systems with relativistic rotational variable mass are studied. The differential equations of motion of the systems are established. The definition and criterion of the Mei symmetries and the Lie symmetries of the system are studied respectively. The necessary and sufficient condition under which the Mei symmetry is Lie symmetry is given. The condition under which the Mei symmetries can be led to a new kind of conserved quantity and the form of the conserved quantity are obtained. An example is given to illustrate the application of the results.  相似文献   
6.
Five new transition metal coordination polymers based on H2tzda and co-ligand bpe, {[M(tzda)(bpe)]·H2O}n [M=Zn(1), Cd(2), Mn(3), Co(4)] and [Ni2(tzda)2(bpe)2(H2O)]n (5) [H2tzda=(1,3,4-thiadiazole-2,5-diyldithio)diacetic acid, bpe=1,2-bis(4-pyridyl)ethane], have been hydrothermally synthesized and structurally characterized. Compounds 1-4 feature a 2D-layered architecture generated from [M(tzda)]n moiety with double-chain structure cross-linking bpe spacers. However, the conformations bpe adopts in 3 and 4 are different from those in 1 and 2 due to the rotation of C-C single bond in bpe. Polymer 5 exhibits an interesting 3D porous framework with 2-fold interpenetration, in which intriguing 1D double helix chains are observed. The photoluminescence properties of 1 and 2 in the solid-state at room temperature are investigated. In addition, variable-temperature magnetic data show weak antiferromagnetic behavior in 3-5.  相似文献   
7.
The conformal meehanico-electrical systems are presented by infinitesimal point transformations of time and generalized coordinates. The necessary and suflleient conditions that the eonformal meehanieo-eleetrieal systems possess Lie symmetry are given. The Noether conserved quantities of the eonformal meehanieo-eleetrieal systems are obtained from Lie symmetries.  相似文献   
8.
The perturbation of symmetries and Mei adiabatic invariants of nonholonomic systems with servoconstraints are studied. The exact invariants in the form of Mei conserved quantities introduced by the Mei symmetry of nonholonomic systems with servoconstraints without perturbations are given. Based on the definition of higher-order adiabatic invariants of mechanical systems, the perturbation of Mei symmetries for nonholonomic .systems with servoconstraints under the action of small disturbance is investigated, and Mei adiabatic invatiants of the system are obtained. An example is given to illustrate the application of the results.  相似文献   
9.
用双道原子荧光分光光度计,断续流动程序和消解体系,测定灵芝中的汞,试验回收率在89.2%-106.3%之间.  相似文献   
10.
This paper concentrates on studying the symmetries and a new type of conserved quantities called Mei conserved quantities for Nonholonomic Systems with Servoconstraints. The criterions of the Mei symmetry, the Noether symmetry, and the Lie symmetry are given. The conditions and the forms of the Mei conserved quantities deduced from these three symmetries are obtained. An example is given to illustrate the appfication of the results.  相似文献   
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