In this work, we assessed the in-vitro effects of eicosapentaenoic acid (EPA; C20:5n-3) and docosahexaenoic acid (DHA; C22:6n-3) (final concentration, 15 microM) on T cell blastogenesis, interleukin-2 and -4 (IL-2, IL-4) secretion, fatty acid composition and intracellular oxidative status in type I diabetic patients with or without complications. Con A stimulated lymphocyte proliferation, glucose uptake, intracellular reduced glutathione levels and catalase activity were lower in diabetics as compared to controls, regardless to the presence of complications. EPA and DHA diminished T-lymphocyte proliferation and IL-2 production but enhanced IL-4 secretion in both diabetic and control groups. No changes in the levels of reduced glutathione and in the activities of catalase and SOD were observed in control T cells cultured in the presence of EPA and DHA. However, in diabetic patients, addition of n-3 PUFA to culture induced an increase in T cell levels of reduced glutathione and hydroperoxide, and in activities of catalase and SOD. Low levels of arachidonic acid (C20:4n-6) were found in plasma membrane phospholipids of lymphocytes from diabetic patients compared to controls. Incubation of lymphocytes with EPA and DHA was associated with an incorporation of these fatty acids in membrane phospholipids. In conclusion, the beneficial effects of n-3 PUFA on T cell functions in type I diabetes could be attributed to their suppressive action and modulation of cytokine secretion, and to the improvement of intracellular oxidative status. 相似文献
Two series samples of Iron Oxide nanoparticles doped with nickel and cobalt with different doping values (x?=?0.01; 0.03; 0.05 and 0.07), were successfully synthesized by using sol–gel method, and then they were characterized by X-ray diffraction, scanning electron and vibrating sample magnetometer (VSM). X-ray diffraction analysis of two series samples showed the formation α-Fe2O3 nanoparticles, accompanied by two phases iron spinels, CoFe2O4 and NiFe2O4. In addition, the variations in grain size were observed for both two series. The observation by scanning electron microscopy reveals a change in the morphology of the grains of all the samples doped, which confirm the cobalt and nickel effect on the morphology of iron oxide nanoparticles. Magnetic measurements which were measured by VSM showed significant magnetic parameters such as coercivity and magnetization besides the ferromagnetic behavior of both two series doped with Cobalt and Nickel.
Silica-supported nickel catalysts have been prepared by a solventless technique involving the deposition of the [Ni(tmen)(acac)2] precursor from the gas phase. According to UV–vis and IR spectroscopy and to elemental analysis, the initial deposition step results in the grafting of Ni(II) complexes on silanol groups to give predominantly [Ni(acac)2 (Si-OH)2]0 monomeric inner-sphere complexes, with elimination of the neutral (tmen) ligands into the gas phase. Subsequent thermal treatments in oxidising atmospheres causes an oxidative decomposition of the (acac) ligands without nickel desorption or coalescence into oxide crystallites. The ensuing coordinatively unsaturated Ni(II) centres are reduced to Ni(0) by flowing hydrogen at low temperatures (300 °C), yielding nanosized Ni particles as evidenced by TEM and O2 titration. Thus, the gas-phase deposition technique represents an interesting alternative to conventional wet deposition procedures since it allows one to obtain well-dispersed supported nickel catalysts by reduction at low-temperatures. 相似文献
Broccoli is an important source of many nutritional and bioactive compounds. However, its shelf-life is very short due to physicochemical losses and microbiological degradation. This study was undertaken to implement treatments that could improve the quality of ready-to-eat (RTE) broccoli during storage by evaluating the effect of pre-treatment with calcium chloride (CaCl2) and alginate coating on the physicochemical and microbial properties of RTE broccoli. Broccoli florets were pre-treated with three different concentrations of CaCl2 (1, 2.5, and 4 g L?1), then coated with an alginate formulation (13 g L?1) and stored at 4 °C for 24 days. Texture, color, weight loss, respiration rate, and total mesophilic flora (TMF) counts were evaluated at days 0, 3, 7, 14, and 24 of storage. The obtained results in this study showed that combining pre-treatment with calcium and alginate coating led to reducing the weight loss and respiration rate of broccoli, maintaining its color and texture as well as extending its shelf-life by 6 days. These results not only allowed reducing post-harvest losses resulting in the loss of the product but also have a major impact on the environment and resources involved in the production process. 相似文献
‘Sikitita’ is a new olive cultivar developed in Spain by crossing the cultivars ‘Picual’ and ‘Arbequina’. The phenolic fraction of olive leaves (Olea europaea L.), is purported to have good anti-oxidative properties which help to prevent several health problems. To our knowledge, no studies are available on the phenolic fraction of ‘Sikitita’ olive leaves or any other new cultivar developed from breeding. Thus, the identification and quantification of the phenolic fraction of ‘Sikitita’ olive leaves by HPLC-DAD-MS were studied and compared with those of its parent cultivars. The three cultivars were grown under the same agronomic and environmental conditions in the same orchard. The quantification was performed using HPLC-DAD, whereas qualitative data were acquired using HPLC-MS. It was thus possible to identify 30 different compounds, two of which have been tentatively characterized for the first time in olive leaves of Spanish cultivars. Significant differences between cultivars were observed for almost all the compounds. Results for ‘Sikitita’ olive leaves presented a higher degree of similarity with respect to ‘Picual’ than to ‘Arbequina’. Further work will monitor the time course of phenolic compounds over the growth period. 相似文献
Yield stress in compression (0.2% flow stress) from ambient temperature up to 800 °C has been studied on Ni3(Al, Si) alloy with the atomic composition Ni78Al11Si11. When annealed at 1000 °C, the alloy has a pure L12 (γ′) ordered structure. After subsequent annealing at 750 °C, the disordered solid solution of Al and Si in Ni (face centred cubic, γ) precipitates in fine coherent particles. Calorimetry helps to describe the various phase transformations necessary to obtain the last microstucture. Solute addition of Si, which replaces Al atoms, increases the 0.2% flow stress of Ni3Al in the fully γ′ microstructure. The γ precipitation shifts the peak stress towards higher temperatures and stresses. 相似文献