In this work, we combined various parameters found in the literature for the choline cation, chloride anion, and ethylene glycol to set up force field models (FFMs) for a eutectic mixture, namely, ethaline (1:2 choline chloride/ethylene glycol (ChCl:2EG)). The validation of these models was carried out on the basis of physical and chemical properties, such as the density, expansion coefficient, enthalpy of vaporization, self-diffusion coefficients, isothermal compressibility, surface tension, and shear viscosity. After the initial evaluation of the FFMs, a refinement was found necessary and accomplished by taking into account polarization effects in a mean-field manner. This was achieved by rescaling the electrostatic charges of the ions based on partial charges derived from ab initio molecular dynamics (MD) simulations of the bulk system. Classical all-atom MD simulations performed over a large range of temperatures (298.15-373.15 K) using the refined FFMs clearly showed improved results, allowing a better prediction of experimental properties. Specific structural properties (radial distribution functions and hydrogen bonding) were then analyzed in order to support the adequacy of the proposed refinement. The final selected FFM leads to excellent agreement between simulated and experimental data on dynamic and structural properties. Moreover, compared to the previously reported force field model (Perkins, S. L.; Painter, P.; Colina, C. M. Experimental and Computational Studies of Choline Chloride-Based Deep Eutectic Solvents. J. Chem. Eng. Data 2014, 59, 3652-3662), a 10% improvement in simulated transport properties, i.e., self-diffusion coefficients, was achieved. The isothermal compressibility, surface tension, and shear viscosity for ethaline are accessed in MD simulations for the first time.

The development of new therapeutic approaches, combining efficacy and safety against intestinal inflammation, notably inflammatory bowel disease (IBD), has emerged as an important goal due to the significant side effects and the lack of effectiveness of standard current therapies. Recently, several studies described the health-promoting effects of red wine, including anti-inflammatory properties, but the molecular mechanisms underlying its beneficial role remain largely unknown. Red wine is rich in phenolic compounds and it has been suggested that the positive effect of red wine intake might be attributed not only to the antioxidant properties of these compounds but also to the modulation of signalling cascades in connection with physiological and pathophysiological conditions such as inflammatory processes. This study assesses the potential anti-inflammatory action of a red wine extract (RWE) enriched in polyphenols in a cellular model of intestinal inflammation using cytokines-stimulated HT-29 colon epithelial cells. RWE suppressed cytokines-induced IκB degradation and interleukin-8 production in a dose-dependent manner. Coherently, key inflammatory mediators downstream NF-κB activation; notably cyclooxygenase-2 and inducible nitric oxide synthase were maintained at low levels by RWE in the presence of the cytokines. Additionally, RWE inhibited both the increase of nitric oxide derived from iNOS and of protein tyrosine nitration, a biomarker of nitrosative stress that typically requires the reaction of nitric oxide with the superoxide radical. Taken together, the anti-inflammatory action of RWE, mechanistically supported by the modulation of cascades orchestrated by NF-κB and involving nitric oxide, suggests that RWE (a readily straightforward preparation when compared with the purification of specific compounds) may represent a simple and inexpensive therapeutic strategy in the context of intestinal inflammation.

The results of a systematic molecular dynamics study of the interfacial structure between the gold (100) surface and two room-temperature ionic liquids, namely, 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIm][PF6]) and 1-butyl-3-methylimadazolium bis(trifluoromethylsulfonyl)imide ([BMIm][NTf2]), are herein reported. It is found that near an uncharged surface the IL structure differs from its bulk, having an enhanced density extended until the two first layers. Interfacial layering is clearly observed at the gold surface, with a higher effect for the [BMIm][NTf2] IL but a higher packing for [BMIm][PF6]. In both ILs the alkyl side chains are oriented parallel to the interface while the imidazolium rings tend to be parallel to the interface in about 60% of the cases. The presence of the interface has a higher impact on the orientation of the cations than on the chemical properties of the counterion. The surface potential drop across the interface is more pronounced toward a negative value for ([BMIm][PF6]) than for ([BMIm][NTf2]), due to relatively larger local density of the anions for ([BMIm][PF6]) near the gold surface.

No abstract

No abstract

The ion transfer of acetylcholine (AcH + ) ions across the unmodified and phospholipid-modified water|1,2-dichloroethane (DCE) interface has been studied by means of square-wave and cyclic voltammetry, as well as by electrochemical impedance spectroscopy. After being transferred in the organic phase, the AcH + ions undergo chemical reactions with the phospholipids. The overall behavior of the experimental system studied in the presence of phospholipids has been compared with the theoretical results of an ECrev reaction. The kinetic parameters of the chemical interactions between AcH + and the phospholipids have been determined from the voltammetric and impedance measurements. Additional characterization of those interactions has been made by using the surface tension measurements.

No abstract

No abstract