47 research outputs found

    Flowers from Kalanchoe pinnata are a Rich Source of T Cell-Suppressive Flavonoids:

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    The chemical composition and immunosuppressive potential of the flowers from Kalanchoe pinnata (Crassulaceae) were investigated. We found that the aqueous flower extract was more active than the leaf extract in inhibiting murine T cell mitogenesis in vitro. Flavonoids isolated from the flower extract were identified and quantitated based on NMR and HPLC-DAD-MS analysis, respectively. Along with quercetin, four quercetin glycosyl conjugates were obtained, including quercetin 3-O-β-D-glucuronopyranoside and quercetin 3-O-β-D-glucopyranoside, which are described for the first time in K. pinnata. All flavonoids inhibited murine T cell mitogenesis and IL-2 and IL-4 production without cell toxicity. This is the first report on the pharmacological activity of flowers of a Kalanchoe species, which are not used for curative purposes. Our findings show that K. pinnata flowers are a rich source of T-suppressive flavonoids that may be therapeutically useful against inflammatory diseases

    Cashew nuts (Anacardium occidentale L.) decrease visceral fat, yet augment glucose in dyslipidemic rats

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    The objective of this study was to evaluate the biological effects of roasted Cashew nuts consumption on biochemical and murinometric parameters in dyslipidemic rats receiving lipid supplementation. Young male rats were randomly assigned to three experimental groups (n = 10). The Control group (CONT) was treated with water, the Dyslipidemic group (DL) received a high fat content emulsion throughout the experiment, and the Dyslipidemic Cashew Nuts group (DLCN) received the same high fat content emulsion throughout the experiment, yet was treated with Cashew nuts. Body parameters, biochemical, hepatic and fecal fatty acid profiles were all evaluated. The levels of total cholesterol and triglycerides were higher in the DL and DLCN groups as compared to the control group. DLCN and CONT presented no difference in HDL levels. DLCN presented higher glycemia levels than the other groups. There was reduction of body fat in DLCN as compared to other groups, but with higher accumulations of liver fat. DLCN presented a reduction in saturated hepatic fatty acids of 20.8%, and an increase of 177% in relation to CONT; there was also a 21% in increase DL for ω9 fatty acids in comparison to CONT. As for fecal fatty acids, there was a lower concentration of polysaturates in DLCN as compared to the other groups. The data showed that the consumption of Cashew nuts by the dyslipidemic animals treated with a hyperlipidic diet induced greater accumulations of liver fat and worsened glycemic levels, despite having reduced visceral fats and increased fecal fat excretion.info:eu-repo/semantics/publishedVersio

    Experimental study of a positive surge. Part 1: Basic flow patterns and wave attenuation

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    A positive surge results from a sudden change in flow that increases the depth. It is the unsteady flow analogy of the stationary hydraulic jump and a geophysical application is the tidal bore. Positive surges are commonly studied using the method of characteristics and the Saint-Venant equations. The paper presents the results from new experimental investigations conducted in a large rectangular channel. Detailed unsteady velocity measurements were performed with a high temporal resolution using acoustic Doppler velocimetry and non-intrusive free-surface measurement devices. Several experiments were conducted with the same initial discharge (Q=0.060 m³/s) and 6 different gate openings after closure resulting in both non-breaking undular and breaking bores. The analysis of undular surges revealed wave amplitude attenuation with increasing distance of surge propagation were in agreement with Ippen and Kulin theory. Also, undular wave period and wave length data were relatively close to the values predicted by the wave dispersion theory for gravity waves in intermediate water depths

    Comparative analysis of HLLC-and roe-based models for the simulation of a dam-break flow in an erodible channel with a 90¿ bend

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    In geophysical surface flows, the sediment particles can be transported under capacity (equilibrium) conditions or noncapacity (nonequilibrium) conditions. On the one hand, the equilibrium approach for the bedload transport assumes that the actual transport rate instantaneously adapts to the local flow features. The resulting system of equations, composed of the shallow water equations for the flow (SWE) and the Exner equation for the bed evolution, has been widely used to simulate bedload processes. These capacity SWE + Exner models are highly dependent on the setup parameters, so that the calibration procedure often disguises the advantages and flaws of the numerical method. On the other hand, noncapacity approaches account for the temporal and spatial delay of the actual sediment transport rate with respect to the capacity of the flow. The importance of assuming nonequilibrium conditions in bedload numerical models remains uncertain however. In this work, we compared the performances of three different strategies for the resolution of the SWE + Exner system under capacity and noncapacity conditions to approximate a set of experimental data with fixed setup parameters. The results indicate that the discrete strategy used to compute the intercell fluxes significantly affected the solution. Furthermore, the noncapacity approach can improve the model prediction in regions with complex transient processes, but it requires a careful calibration of the nonequilibrium parameters. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
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