BSA adsorption onto negatively and positively charged polystyrene nanoparticles was investigated. The nanoparticles were characterized in terms of particle size, zeta potential, surface group density, and morphology. The adsorption behavior of BSA on the particle surface, as a function of pH and overall charge of the particle, was studied using ITC. Different thermodynamic data such as enthalpy changes upon binding and stoichiometry of the systems were determined and discussed. The degree of surface coverage with BSA was calculated using the thermodynamic data. The cellular uptake of particles before and after BSA adsorption was studied using HeLa cells in the presence and absence of supplemented FCS in the cell culture medium.

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A growing body of evidence suggests a protective role of polyphenols and exercise training on the disorders of type 2 diabetes mellitus (T2DM). We aimed to assess the effect of the açaí seed extract (ASE) associated with exercise training on diabetic complications induced by high-fat (HF) diet plus streptozotocin (STZ) in rats. Type 2 diabetes was induced by feeding rats with HF diet (55% fat) for 5 weeks and a single dose of STZ (35 mg/kg i.p.). Control (C) and Diabetic (D) animals were subdivided into four groups each: Sedentary, Training, ASE Sedentary, and ASE Training. ASE (200 mg/kg/day) was administered by gavage and the exercise training was performed on a treadmill (30min/day; 5 days/week) for 4 weeks after the diabetes induction. In type 2 diabetic rats, the treatment with ASE reduced blood glucose, insulin resistance, leptin and IL-6 levels, lipid profile, and vascular dysfunction. ASE increased the expression of insulin signaling proteins in skeletal muscle and adipose tissue and plasma GLP-1 levels. ASE associated with exercise training potentiated the reduction of glycemia by decreasing TNF-α levels, increasing pAKT and adiponectin expressions in adipose tissue, and IR and pAMPK expressions in skeletal muscle of type 2 diabetic rats. In conclusion, ASE treatment has an antidiabetic effect in type 2 diabetic rats by activating the insulin-signaling pathway in muscle and adipose tissue, increasing GLP-1 levels, and an anti-inflammatory action. Exercise training potentiates the glucose-lowering effect of ASE by activating adiponectin-AMPK pathway and increasing IR expression.

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A dynamic mathematical model is developed to represent miniemulsion polymerization reactions using oil‐soluble initiator. Both simulation and experimental results show that the evolution of conversion varies with particle diameter and that reactions become slower as the particle size is increased. For each experimental condition, a limiting diameter is obtained, above which the reaction kinetics does not change anymore with the diameter. These results are explained in terms of the compartmentalization of growing radicals during the miniemulsion polymerizations. The evolution of conversion in bulk polymerizations shows that the kinetic behavior above the limiting diameter is similar to the kinetic behavior of bulk reactions. magnified image

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Microwave-assisted decomposition of 2,2 0 -azobis(2-methylpropionamidine) dihydrochloride (or V50), a cationic azo-initiator, and emulsion polymerizations were performed and compared to reactions with conventional heating. Higher decomposition rate constants were found in microwave reactions. This was ascribed to the development of hot spots inside the reaction mixture, promoted by microwave irradiation. In polymerization reactions, microwave-promoted acceleration of the reactions. The effect of high power irradiation was also studied, using a pulsed method in which samples were repeatedly heated at constant power (500 or 1400 W), and cooled down by immersing in an ice bath. Rapid reactions were obtained, because a great amount of energy could be applied within short time intervals. The power level had no effect on the decomposed percentages and on the monomer conversion, and only affected the irradiation time.

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