J Biomater Sci Polym Ed
May 2016
The development of biomedical materials with biocompatibility, especially cytocompatibility, is the frontal research field for material science, biology, medicine, pharmacology and related interdisciplines. We have successfully synthesized a new biomedical material, PNIPAM-g-P(NIPAMco-St) (PNNS) core-shell nanoparticles, and investigated its thermosensitive and fluorescent properties. In order to evaluate the cytocompatibility of the PNNS nanoparticles, the effect of the PNNS nanoparticles on the human ether-àgo-go-related gene (hERG) K(+) channel in HEK-293 cells was investigated for the first time with the inverted fluorescence microscope and the whole-cell patch-clamp technique.
View Article and Find Full Text PDFAccid Anal Prev
November 2011
Animal-Vehicle Collisions (AVCs) have been a major safety problem in the United States over the past decades. Counter measures against AVCs are urgently needed for traffic safety and wildlife conservation. To better understand the AVCs, a variety of data analysis and statistical modeling techniques have been developed.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
November 2011
This study described the bioelectrochemistry property of hemoglobin (Hb) on biopolymer film of polyurethane ionomer nanoparticles (PUI-NPs) noncovalently functionalized with multiwall carbon nanotubes (MWCNTs). The polyurethane ionomer nanoparticles (PUI-NPs) were synthesized by emulsion polymerization, and could provide a good biocompatible microenvironment for Hb immobilization. The characteristic of (PUI-NPs)/MWCNTs and Hb/(PUI-NPs)/MWCNTs composite films were performed by using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and circular dichroism (CD).
View Article and Find Full Text PDFTwo thin-film (10)B samples on tantalum backings were made for measurement of cross sections of the (10)B(n,α)(7)Li reaction in the MeV neutron energy region. The number of (10)B atoms in the samples was determined using the relative comparison method by detecting alpha and triton particles from thermal neutron induced nuclear reactions of (10)B(n(th),α)(7)Li and (6)Li(n(th),t)(4)He with a (6)LiF sample as the reference. A twin gridded ionization chamber was used as the detector of charged particles.
View Article and Find Full Text PDFIt has been reported that pretreatment of rats with lipopolysaccharide (LPS) increases myocardial functional recovery in ischemia/reperfusion (I/R) hearts. However, the mechanisms by which LPS induces cardioprotection against I/R injury have not been fully elucidated. In this study, we pretreated rats with LPS (1.
View Article and Find Full Text PDFBK-type K(+) channels are activated by voltage and intracellular Ca(2+), which is important in modulating muscle contraction, neural transmission, and circadian pacemaker output. Previous studies suggest that the cytosolic domain of BK channels contains two different Ca(2+) binding sites, but the molecular composition of one of the sites is not completely known. Here we report, by systematic mutagenesis studies, the identification of E535 as part of this Ca(2+) binding site.
View Article and Find Full Text PDFCa(2+)-activated BK channels modulate neuronal activities, including spike frequency adaptation and synaptic transmission. Previous studies found that Ca(2+)-binding sites and the activation gate are spatially separated in the channel protein, but the mechanism by which Ca(2+) binding opens the gate over this distance remains unknown. By studying an Asp-to-Gly mutation (D434G) associated with human syndrome of generalized epilepsy and paroxysmal dyskinesia (GEPD), we show that a cytosolic motif immediately following the activation gate S6 helix, known as the AC region, mediates the allosteric coupling between Ca(2+) binding and channel opening.
View Article and Find Full Text PDFAim: To study the role of hypoxia-inducible factor 1-alpha (HIF-1alpha) on hypoxia-induced apoptosis in primary neonatal rat ventricular myocytes.
Methods: Primary neonatal rat ventricular myocytes were exposed to hypoxia for 24 hours. HIF-1alpha activity was suppressed by treating the cells with 3-(5'-hydroxymethyl-2'- furyl)-1-benzyl indazole (YC-1).
An optimized microwave-assisted extraction (MAE) method and an efficient HPLC analysis method were developed for fast extraction and simultaneous determination of oleanolic acid and ursolic acid in the fruit of Chaenomeles sinensis. The open vessel MAE process was optimized by using a central composite experimental design. The optimal conditions identified were microwave power 600 W, temperature 52 degrees C, solvent to material ratio 32 mL/g and extraction time 7 min.
View Article and Find Full Text PDFMeasurements of cross sections of the (95)Mo(n, alpha)(92)Zr reaction at E(n)=4.0, 5.0 and 6.
View Article and Find Full Text PDFBackground: Mesenchymal stem cells (MSCs)-based regenerative therapy is currently regarded as an alternative approach to salvage the acute myocardial infarcted hearts. However, the efficiency of MSCs transplantation is limited by lower survival rate of engrafted MSCs. In previous study, we found that 1.
View Article and Find Full Text PDFThe voltage-sensor domain (VSD) and the ligand sensor (cytoplasmic domain) of BK channels synergistically control channel activities, thereby integrating electrical and chemical signals for cell function. Studies show that intracellular Mg2+ mediates the interaction between these sensory domains to activate the channel through an electrostatic interaction with the VSD. Here we report that Mg2+ binds to a site that consists of amino acid side chains from both the VSD (Asp99 and Asn172) and the cytoplasmic domain (Glu374 and Glu399).
View Article and Find Full Text PDFCross sections of the (147)Sm(n, alpha)(144)Nd reaction were measured at En=5.0 and 6.0MeV.
View Article and Find Full Text PDFAppl Radiat Isot
October 2008
Cross-sections of the (10)B(n, alpha)(7)Li reaction were measured at En=4.0 and 5.0 MeV.
View Article and Find Full Text PDFLarge conductance Ca(2+)- and voltage-activated K(+) (BK) channels, composed of pore-forming alpha-subunits and auxiliary beta-subunits, play important roles in diverse physiological processes. The differences in BK channel phenotypes are primarily due to the tissue-specific expression of beta-subunits (beta1-beta4) that modulate channel function differently. Yet, the molecular basis of the subunit-specific regulation is not clear.
View Article and Find Full Text PDFAppl Radiat Isot
December 2007
Cross sections of 141Pr(n,gamma) 142Pr reaction are measured at neutron energies of 0.54, 1.09 and 1.
View Article and Find Full Text PDFAn accurate measurement of the 4.438 MeV gamma-ray to total neutron ratio, namely R=Sgamma/Sn, for a Chinese-made Am-Be neutron source is described. The neutron strength of the source relative to a previously standardized source was determined by the manganese bath technique.
View Article and Find Full Text PDFZhonghua Xin Xue Guan Bing Za Zhi
October 2006
Objective: Patient with myocardial bridging (MB) usually has a benign prognosis, but some MB patients might experience myocardial ischemia, infarction and sudden cardiac death, especially during active physical activities. The purpose of the study was to study the stress-induced blood flow changes of the mural coronary artery in MB patients determined by intracoronary Doppler.
Methods: In 8 patients with MB, the basic average peak velocity (bAPV), hyperemic average peak velocity (hAPV) of blood flow, coronary flow reverse (CFR) proximal and distal to the mural coronary artery were measured before and during intravenously dobutamine (10 microg kg-1 min-1, then add 10 microg kg-1 min-1 at 3 min interval till 40 microg kg-1 min-1) by intracoronary Doppler.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
June 2005
A model of fluid dynamics related to the myocardial bridginged and mural coronary artery was designed and manufactured according to the physical principle and characteristic of the mural coronary artery. The model can imitate systematically well the effect of myocardial bridging on hemodynamic change of the mural coronary artery under different controlled experimental parameter. The methodology is proved to be feasible and has good prosperity of experimental study.
View Article and Find Full Text PDFZhonghua Xin Xue Guan Bing Za Zhi
February 2005
Objective: To assess the effect of beta blocker on blood flow velocity and reserve on the intramural coronary artery of patients with myocardial bridging.
Methods: In 8 patients with myocardial bridge, intracoronary Doppler was performed before and after esmolol was given intravenously. The basic average peak velocity (bAPV), hyperaemic average peak velocity (hAPV) of blood flow, and coronary flow reserve (CFR) proximal and distal to the mural myocardial bridging was measured and compared.
Unlabelled: To study the effects of lead exposure on nitric oxide (NO), nitric oxide synthase (NOS), super oxide dismutase (SOD) and malondialdehyde (MDA) in cerebral cortex of rats, Wistar rats are exposed to lead from drinking 0, 18.4, 184 mg/L lead acetate solution respectively.
Results: Cerebral cortex NOS activity in low and high-dosed lead exposure groups are significantly increased at the time of 7 days (P < 0.
In anhydrous CH3CN a series of nine 4-(4-substituted-benzoyl)-N-methylpyridinium cations (substituent: -OCH3, -CH3, -H, -SCH3, -Br, -Ctbd1;CH, -CHO, -NO2, and -(+)S(CH3)2) demonstrate two chemically reversible, well-separated one-electron (1-e) reductions in the same potential range as other main stream redox catalysts such as quinones and viologens. Hammett linear free energy plots yield excellent correlation between the E(1/2) values of both waves and the substituent constants sigma(p)(-)(X). The reaction constants for the two 1-e reductions are rho(1) = 2.
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