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Abstract  

Rare earth picrate complexes with L-leucine (Leu) were synthesized and characterized. Elemental analysis (CHN), EDTA titrations and thermogravimetric data suggest a general formula RE(pic)32Leu⋅5H2O (RE=La–Lu, Y and pic=picrate). IR spectra indicate the presence of water and suggest that L-leucine is coordinated to the central ion through the nitrogen of the aminogroup. The absorption spectrum of the solid Nd compound indicates that the metal-ligand bonds show a weak covalent character. Emission spectra and biexponential behavior of the luminescence decay of the Eu compound suggest the existence of polymeric species. Thermal analysis results indicate that all the compounds present a similar behavior, with five major thermal decomposition steps. The final products are rare earth oxides. A slow heating rate is necessary to observe all decomposition steps.

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Abstract  

Captopril (CAP) was the first commercially available angiotensine-converting enzyme (ACE) inhibitor. In the anti-hypertensive therapy is considered the selected drug has to be therapeutically effective together with reduced toxicity. CAP is an antihypertensive drug currently being administered in tablet form. In order to investigate the possible interactions between CAP and excipients in tablets formulations, differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis completed by X-ray powder diffraction (XRPD) and Fourier transform infrared spectroscopy (FTIR) were used for compatibility studies. A possible drug-excipient interaction was observed with magnesium stearate by DSC technique.

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Journal of Thermal Analysis and Calorimetry
Authors: B. de Cominges, M. Piñeiro, E. Mosteiro, E. Mascato, M. Mato, T. Iglesias, and J. Legido

Abstract  

The aim of this work is to complete our studies on physical properties of binary mixtures of alkane+1-alkanols. This work reports densities, refractive indices, speeds of sound and isentropic compressibilities of the mixture octane + 1-butanol at different temperatures, from 288.15 to 308.15 K. From the experimental values, the corresponding excess and deviation values were computed (excess molar volumes, changes of refractive index on mixing, changes of speed of sound on mixing and changes of isentropic compressibilities on mixing). The results were fitted to variable-degree polynomials. Excess molar volumes were compared with the predictions of Nitta-Chao Group Contribution Model.

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Summary  

Rare earth picrate (RE) complexes with L-lysine (Lys) were synthesized and characterized. Elemental analysis (CHN), EDTA titrations and thermogravimetry data suggest a general formula RE(pic)32Lys2H2O, where RE=La-Lu (without Pm) and Y, pic=picrate). IR spectra suggest that Lys is coordinated to the central ion through the nitrogen of the α-amino group. Parameters obtained from the absorption spectrum of the Nd compound indicated that the metal-ligand bonds are essentially electrostatic. Emission spectrum and biexponential behavior of the luminescence decay of the Eu compound suggest the existence of polymeric species. Thermogravimetric/derivative thermogravimetric (TG/DTG) and differential scanning calorimetry (DSC) curves of all complexes are very similar, with five events. The final products are the corresponding rare earth oxides and their X-ray diffraction patterns are identical to the calcinated oxides.</o:p>

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Parvovirus infection of Muscovy ducks caused by a genetically and antigenically distinct virus has been reported from Germany, France, Israel, Hungary, some Asian countries and the USA. The pathological changes include those of degenerative skeletal muscle myopathy and myocarditis, hepatitis, sciatic neuritis and polioencephalomyelitis. In the study presented here, day-old and 3-week-old goslings and Muscovy ducks were infected experimentally with three different parvovirus strains (isolates of D-216/4 from the classical form of Derzsy's disease, D-190/3 from the enteric form of Derzsy's disease, and strain FM from the parvovirus disease of Muscovy ducks). All three parvovirus strains caused severe disease in both day-old and 3-week-old Muscovy ducks but in the goslings only the two strains of goose origin (D-216/4 and D-190/3) caused disease with high (90-100%) mortality when infection was performed at day old. Strain FM (of Muscovy duck origin) did not cause any clinical signs or pathological lesions in the goslings. In the day-old goslings and Muscovy ducks the principal pathological lesions were severe enteritis with necrosis of the epithelial cells (enterocytes) of the mucous membrane and the crypts of Lieberkühn, and the formation of intranuclear inclusion bodies. Other prominent lesions included hepatitis and atrophy (lymphocyte depletion) of the lymphoid organs (bursa of Fabricius, thymus, spleen). In goslings infected with the strain originating from the classical form of Derzsy's disease mild myocarditis was also detected. After infection at three weeks of age, growth retardation, feathering disorders, myocardial lesions (degeneration of cardiac muscle cells, lympho-histiocytic infiltration) and hepatitis were the most prominent lesions in both geese and Muscovy ducks. In addition to the lesions observed in the geese, muscle fibre degeneration, mild sciatic neuritis and polioencephalomyelitis were also observed in the Muscovy ducks infected with any of the three parvovirus strains.

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