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1.
The farnesoid X receptor (FXR, NR1H4) has been recognized as an attractive therapeutic target because it is a nuclear hormone
receptor that controls the expression level of cholesterol-7α-hydroxylase, which in turn regulates bile acid production and
cholesterol excretion. To compare receptor activity between each domain and the full-length protein, human FXR cDNA was cloned
from a human liver cDNA library. Three human FXR cDNA, designated FXR20, FXR33, and FXR53 cDNA, were subcloned and ligated into a pET28a expression vector. Each protein was expressed in Escherichia coli (BL21) and purified by nickel-nitrilotriacetic acid column chromatography. Approximately 5 mg of FXR33 (1–182 amino acids deleted from FXR, 37 kDa) and 2 mg of FXR53 (the full-length protein of FXR, 59 kDa) was purified from 1 L of Luria-Bertani culture, achieving at least 90% purity. The
coactivator recruitment assay for FXR activation was carried out with the three variants of the FXR protein by using dissociation-enhanced
lanthanide fluoroimmunoassay-europium-N1-labeled anti-His antibody. From an optimized assay, a saturated hyperbolic fluorescence signal curve was produced when 250
nM of FXR33 and 100 nM of steroid receptor coactivator-1 peptide, a coactivator of FXR consisting of 26 amino acids, were used with a
concentration dependence on chenodeoxycholic acid (from 0 to 200 μM). The ligand-binding domain of FXR (FXR33) was the most suitable protein for studying the activation of FXR with a fluorescence-based assay, because it showed better
structural stability than either the full length of FXR (FXR53) or the DNA-binding domain of FXR (FXR20). 相似文献
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In a previous study, CETP inhibitory peptide (3 kDa) was isolated from hog plasma. The peptide, synthesized chemically according
to the amino acid sequence of the 3-kDa peptide (designated P28), showed CETP inhibitory activity both in vitro and in vivo [Cho et al. (1998) Biochim. Biophys. Acta 1391, 133–144]. We report herein further unique features of P28 when it was associated with the cholesteryl ester (CE)-donor and-acceptor lipoproteins. Lipoprotein substrates with P28 present in both HDL (as a CE-donor) and LDL (as a CE-acceptor) served as poor substrates, with CE-transfer activity decreased
up to 60% compared to normal substrates without P28. P28 was found to be located in HDL fractions of hog plasma and showed the same electromobility as that visualized by PAGE on
7% polyacrylamide gel under nondenaturing conditions. Addition of apolipoprotein A-1 (apoA-1) or apoB antibody to a normal
CE-transfer mixture did not alter CE-transfer activity. However, addition of apoA-1 or −B antibody to a CETP-inhibition mixture
decreased the inhibitory activity of P28 by ca. 20%. Western blot analysis revealed that P28 was associated only with human and hog HDL among several lipoproteins purified from human, hog, and rabbit. CFTP-inhibition
assays with various lipoprotein substrates revealed that P28 exhibited substrate-specific inhibitory activity. The inhibitory activity of P28 was highly dependent on the type of lipoprotein substrate (whether CE-donor or-acceptor); P28 inhibited CE transfer from HDL to LDL, but it did not inhibit CE transfer from HDL to HDL. 相似文献
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This study examined the surface nanostructures of three orbital implants: nonporous poly(methyl methacrylate) (PMMA), porous aluminum oxide and porous polyethylene. The morphological characteristics of the orbital implants surfaces were observed by atomic force microscopy (AFM). The AFM topography, phase shift and deflection images of the intact implant samples were obtained. The surface of the nonporous PMMA implant showed severe scratches and debris. The surface of the aluminum oxide implant showed a porous structure with varying densities and sizes. The PMMA implant showed nodule nanostructures, 215.56 ± 52.34 nm in size, and the aluminum oxide implant showed crystal structures, 730.22 ± 341.02 nm in size. The nonporous PMMA implant showed the lowest roughness compared with other implant biomaterials, followed by the porous aluminum oxide implant. The porous polyethylene implant showed the highest roughness and severe surface irregularities. Overall, the surface roughness of orbital implants might be associated with the rate of complications and cell adhesion. SCANNING 33: 211–221, 2011. © 2011 Wiley Periodicals, Inc. 相似文献
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研究适合导弹自适应自动驾驶仪设计中对于参数快速变化的有效的辨识方法,从几种时变参数辨识方法的研究着手,经过适当的修改和组合,得出适用的辨识方法。通过从理论分析到微机仿真等一系列工作,证明了这一辨识方法能够较好跟踪导弹气动参数的变化。 相似文献
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为了设计用超临界流体抗溶剂结晶(GAS)法制备葛根素的超细颗粒,用静态平衡法考察了超临界CO2溶胀过程中葛根素在乙醇溶液的溶解特性.实验结果表明,体系压力变化对溶解度的影响最为显著.同时,我们发现,伴随着体系压力的递增,溶液中葛根素浓度表现为先扬后抑的趋势,甚至大于其初始值.由此可知,GAS过程CO2兼有抗溶剂和萃取剂的双重功能:前者降低溶质的溶解度,后者则提高溶液浓度. 相似文献
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Underwater radiated noise is one of the most important performances related to the stealth of a naval vessel. However, the evaluation frequently cannot be performed due to the problem of the test expense. The specification of the hull vibration is an effective method used to specify the underwater radiated noise indirectly. Therefore, in order to specify hull vibration, the sound radiation efficiency should be correctly determined. In this paper, the sound radiation efficiency which was modified with experimentally derived sound radiation efficiency as well as Maidanik’s and Uchida’s sound radiation efficiency is suggested and verified through experiments. Based on the determined sound radiation efficiency in this research, the specification of the hull vibration to satisfy with the limit of the underwater radiated noise is suggested for a ship. 相似文献
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Since the engine and reduction gears in naval vessels are usually supported by a separate mounting system, misalignment between the reduction gears’ input shaft and the engine’s power transfer shaft occurs as a result of the ship’s motion. In this study, this misalignment is experimentally estimated using CAE by identifying the force and moment of the engine at its center of gravity. The force and moment are calculated using 3 acceleration signals on the engine assuming that the motions of the engine and reduction gear system are rigid-body motion. Using CAE and the estimated force of the engine, the vibration displacement of the engine’s power transfer shaft can be estimated and a design to reduce this vibration displacement can be suggested. 相似文献
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Seong-Jin?Kim Kwon?SonEmail author Kyung-Hyun?Choi 《Journal of Mechanical Science and Technology》2003,17(12):1894-1903
It is necessary to have a dummy that describes the anthropometry of a victim with accuracy. This study presents three scaled
side impact dummies constructed for the use of MADYMO. They represent five, fifty and ninety-five percentile Korean males
ranged from the age of 25 through 39. Thirty-five anthropometric data were used to scale input files required for MADYSCALE.
Geometries, inertia, joints and other parameters for dummies were scaled based on the configurations of EuroSID-1. This study
proposes the lateral impact response requirements for head, thorax and pelvis of Korean side impact dummies. A lateral drop
impact test was conducted for the head at the height of 200 mm. Lateral pendulum impact tests were also carried out for thorax
and pelvis at three specific impact velocities. All these test results were obtained from simulation based on MADYMO. All
the procedures of the three tests followed the requirement of ISO/TR 9790. 相似文献