Gadolinium as a contrast agent in MRI technique combined with DTPA causes contrast induced nephropathy (CIN) and nephrogenic systemic fibrosis (NSF) which can reduce by usage of antioxidants such as N‐acetyl cysteine by increasing the membrane''s permeability leads to lower cytotoxicity. In this study, N ‐acetyl cysteine‐PLGA Nano‐conjugate was synthesized according to stoichiometric rules of molar ratios andafter assessment by FTIR, NMR spectroscopy and Atomic Force Microscopy (AFM) imaging was combined with Magnevist® (gadopentetate dimeglumine) and its effects on the renal cells were evaluated. MTT [3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐Diphenyltetrazolium Bromide] and cellular uptake assays have indicated relatively significant toxicity of magnevist (P < 0.05) on three cell lines including HEK293, MCF7 and L929 compared to other synthesized ligands that shown no toxicity. Moreover, systemic evaluation has shown no notable changes of blood urea nitrogen (BUN) and creatinine in kidney of mice. In consequence, antioxidant effect was increased as well as the renal toxicity of the contrast agent reduced at the cell level. As a result, PLGA‐NAC nano‐conjugate can be a promising choice for decreasing the magnevist toxicity for treatment and prevention of CIN and will be able to open a new horizon to research on reduction of toxicity of contrast agents by using nanoparticles.Inspec keywords: blood, toxicology, nanofabrication, cellular biophysics, biomedical materials, nanoparticles, chromatography, cancer, biodegradable materials, biomedical MRI, kidney, pH, nanomedicine, patient treatment, diseases, atomic force microscopy, Fourier transform infrared spectraOther keywords: cellular toxicity, gadopentate dimeglumine, contrast agent, magnetic resonance imaging technique, diethylenetriamine pentaacetate, contrast‐induced nephropathy, nephrogenic systemic fibrosis, stoichiometric rules, molar ratios, dimethyl sulphoxide solution, chromatography techniques, nuclear magnetic resonance spectroscopy, atomic force microscopy imaging, Magnevist®, gadopentetate dimeglumine, renal cells, MTT cytotoxicity, human embryonic kidney‐293, L929 cell lines, in vitro conditions, cellular uptake assays, Magnevist uptake, antioxidant effect, renal toxicity, cell level, PLGA nanocarrier, acetylcysteine nanoconjugate, Magnevist toxicity, N‐acetylcysteine–PLGA nano‐conjugate, N‐acetyl cysteine‐poly‐lactic‐co‐glycolic acid nanoconjugate相似文献
The use of coating agents is one effective way to reduce oil absorption in fried products. Reducing the fat content of fried foods by application of coatings is an alternative solution to comply with both health concerns and consumer preferences. The aim of this study was to analyze the effect of hydrocolloids as coating agent on the quantity of oil uptake and on sensory attributes of potato chips. The effect of the coating composition showed that the minimum fat content was related to 1% carboxymethyl cellulose (CMC), 0.5% xanthan, 0.3% guar and 1% xanthan with 21.2, 21.7, 22.4 and 24.8%, respectively, and the highest of fat content was related to blank sample (non-coated), 2% tragacanth, 0.5% guar gum with 49.4, 41.7 and 33.2% of oil content, respectively (p <0.05). The most effective coating agent reduced the oil uptake by 57.03, 55.94, 54.67 and 49.71%, respectively (p <0.05). Sensory evaluation showed that the best color was related to 1% CMC, 0.3% guar and 2% tragacanth, and with respect to flavor evaluation the best flavor was observed in tragacanth 2%, CMC 0.5% and CMC 0.1%, and the best texture referred to tragacanth 2%, CMC 0.5% and CMC 1%. In sensory evaluation, all coated chips got high scores compared with blank (non-coated chips) samples (p <0.05). 相似文献
Liquefaction is one of the most destructive natural hazards that cause damage to engineering structures during an earthquake. This study aims to examine the effect of rubber and gravel drainage columns on the reduction of liquefaction potential of saturated sandy soils using a shaking table. Experiments were carried out in various conditions such as construction materials, different arrangements and diameters of drainage columns. Effects of the relative density and the input motion on the base test were investigated as well. The results demonstrate that rubber drainage columns have slightly better performance compared to gravel drainage columns at high relative density and high input acceleration. Soil improvement using gravel drainage columns, which leads to reduction in liquefaction effects at moderate input acceleration and low relative density, is a more effective method than that using rubber drainage columns. By increasing the number and diameter of gravel and rubber drainage columns, deformations due to liquefaction are reduced. The drainage rate of gravel drains is higher than that of rubber drains after shaking. Totally, the outcomes indicate that densification is the most important factor controlling liquefaction. 相似文献
The crosstalk and coupling of the external fields on orthogonal microstrip transmission lines in different layers have significant
effects on signal quality in MMIC and PCBs. In this paper the crosstalk is analyzed in detail using both full-wave and quasi-static
methods. The used full wave method is mixed potential integral equation method of moment (MPIEMoM). Because of the weak coupling between lines, the effect of the incident plane-wave is studied by applying transmission
line theory in a scattered voltage formulation uses quasi-TEM propagation model for each interconnection and the exact distribution
of the incident electric field within the layers. Afterward, by using the predetermined lumped circuit model of the cross-region,
the effect of coupling between two lines is calculated and then applied to terminal voltages in 1–20 GHz frequency range which
results in the final terminal voltages. 相似文献
This paper reports the production of a novel magnetic nanocomposite based on multi-walled carbon nanotubes (MWCNTs) decorated with magnetic core–shell Fe3O4@SiO2 nanoparticles which were used to fabricate a modified carbon paste electrode (Fe3O4@SiO2/MWCNT-CPE). The Fe3O4@SiO2/MWCNT-CPE was investigated for the simultaneous determination of sunset yellow (SY) and tartrazine (TT) in 0.1 mol/L phosphate buffer solution (pH 6.0) using square wave voltammetry (SWV). The synthesized nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy. The proposed electrode exhibits linear ranges of 0.5–100 μmol/L SY and TT with detection limits of 0.05 and 0.04 μmol/L for SY and TT, respectively. The novel proposed voltammetric method was successfully applied in the simultaneous determination of SY and TT in food products, with results similar to those obtained using a HPLC method at 95 % confidence level.
Graphical Abstract A magnetic nanocomposite based on MWCNTs decorated with core–shell Fe3O4@SiO2 was prepared and showed good ability to distinguish the response of SY and TT
Selection of parameters in machining process significantly affects quality, productivity, and cost of a component. This paper presents an optimization procedure to determine the optimal values of wheel speed, workpiece speed, and depth of cut in a grinding process considering certain grinding conditions. Experimental studies have been carried out to obtain optimum conditions. Mathematical models have also been developed for estimating the surface roughness based on experimental investigations. A non-dominated sorting genetic algorithm (NSGA II) is then used to solve this multi-objective optimization problem. The objectives under investigation in this study are surface finish, total grinding time, and production cost subjected to the constraints of production rate and wheel wear parameters. The Pareto-optimal fronts provide a wide range of trade-off operating conditions which an appropriate operating point can be selected by a decision maker. The results show the proposed algorithm demonstrates applicability of machining optimization considering conflicting objectives. 相似文献
Abstract—This article proposes a method that enables ideal sharing of reactive power among converter-based micro-sources in a microgrid with a decentralized control strategy. Power sharing must be properly performed among micro-sources to avoid circulating currents or overloading. Using conventional droop characteristics to achieve power sharing is not satisfactory, as system asymmetry will greatly impact the quality of sharing. In the proposed method, droop characteristic parameters are modified upon a change in system operating point such that ideal sharing takes place after the modification process. Simulation results are presented to show the validity of analysis. 相似文献
This article describes the control optimization of a slotted switched reluctance generator for low-speed applications. The machine is simulated with the finite-element method. The turn-off and turn-on angles are optimized by means of a genetic algorithm to maximize the output power and minimize the torque ripple. First, these two criteria are optimized separately with a mono-objective genetic algorithm, and then a multi-objective Pareto genetic algorithm is used. An analysis of optimized parameters and resulting current waveforms is also performed. Experimental results based on a 6/4 switched reluctance generator are also presented. 相似文献