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Aims The aim of this study is to quantify altered myocardial calcium handling in non-ischaemic cardiomyopathy using magnetic resonance imaging. Methods and results Patients with dilated cardiomyopathy (n = 10) or hypertrophic cardiomyopathy (n = 17) underwent both gadolinium and manganese contrast-enhanced magnetic resonance imaging and were compared with healthy volunteers (n = 20). Differential manganese uptake (Ki) was assessed using a two-compartment Patlak model. Compared with healthy volunteers, reduction in T1 with manganese-enhanced magnetic resonance imaging was lower in patients with dilated cardiomyopathy [mean reduction 257 ± 45 (21%) vs. 288 ± 34 (26%) ms, P < 0.001], with higher T1 at 40 min (948 ± 57 vs. 834 ± 28 ms, P < 0.0001). In patients with hypertrophic cardiomyopathy, reductions in T1 were less than healthy volunteers [mean reduction 251 ± 86 (18%) and 277 ± 34 (23%) vs. 288 ± 34 (26%) ms, with and without fibrosis respectively, P < 0.001]. Myocardial manganese uptake was modelled, rate of uptake was reduced in both dilated and hypertrophic cardiomyopathy in comparison with healthy volunteers (mean Ki 19 ± 4, 19 ± 3, and 23 ± 4 mL/100 g/min, respectively; P = 0.0068). In patients with dilated cardiomyopathy, manganese uptake rate correlated with left ventricular ejection fraction (r2 = 0.61, P = 0.009). Rate of myocardial manganese uptake demonstrated stepwise reductions across healthy myocardium, hypertrophic cardiomyopathy without fibrosis and hypertrophic cardiomyopathy with fibrosis providing absolute discrimination between the healthy myocardium and fibrosed myocardium (mean Ki 23 ± 4, 19 ± 3, and 13 ± 4 mL/100 g/min, respectively; P < 0.0001). Conclusion The rate of manganese uptake in both dilated and hypertrophic cardiomyopathy provides a measure of altered myocardial calcium handling. This holds major promise for the detection and monitoring of dysfunctional myocardium, with the potential for early intervention and prognostication.

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Viscosities, densities, dielectric constants, and refractive Indexes were determined for ethanol-dloxane mixtures at 15, 20, 25, 30, and 35 °C. These properties are represented by means of empirical relations wherein the composition and temperature effects are Involved. The analysis of the dielectric constant data revealed experimental evidence of molecular interactions between the components of the system.

Two cycles of sorption/desorption of water or ethanol by light-cured dental resins of bisphenol A glycol dimethacrylate (Bis-GMA), bisphenol A ethoxylated dimethacrylate (Bis-EMA) urethane dimethacrylate (UDMA) triethylene glycol dimethacrylate and decanediol dimethacrylate (D 3 MA) were studied. The experimental curves m t 5 f(t) taken for the first water sorption by poly-Bis-GMA, poly-Bis-EMA and poly-UDMA showed a maximum. A maximum was also observed in the curve obtained for first sorption of ethanol by poly-Bis-GMA. In all other cases, the curves for sorption or desorption of water or ethanol showed Fickian behavior. The experimental data obtained for first sorption of water or ethanol were perfectly fitted to a new proposed equation, which predicts water or ethanol sorption with simultaneous extraction of unreacted the monomer. This equation gave us the possibility for the determination of the diffusion coefficient of the extraction of the unreacted Bis-GMA during the water and ethanol sorption, as well as the diffusion coefficient of the extraction of the unreacted Bis-EMA and UDMA during the water sorption. The maximum water or ethanol absorbed at equilibrium and the diffusion coefficient are determined from the second sorption/desorption cycle during which the extraction of the monomer is negligible.

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Vlscosttle», densities, dielectric constants, and refractive Indexes were determined for ethanol-cyclohexane mixtures at 15, 20, 25, 30, 35 °C and over the whole composition range. These properties are represented by means of empirical relations wherein the composition and temperature effects are Involved. These equations fit the experimental data with an uncertainty of the same order of magnitude with the corresponding experimental error. The analysis of data evidences the occurrence of changes In the self-association of ethanol with changing composition.