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  • Author or Editor: M. Filho x
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Abstract  

In this study, blood serum trace elements, biochemical and hematological parameters were obtained to assess the health status of an elderly population residing in São Paulo city, SP, Brazil. Results obtained showed that more than 93% of the studied individuals presented most of the serum trace element concentrations and of the hematological and biochemical data within the reference values used in clinical laboratories. However, the percentage of elderly presenting recommended low density lipoprotein (LDL) cholesterol concentrations was low (70%). The study indicated positive correlation between the concentrations of Zn and LDL-cholesterol (p < 0.06).

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Summary  

In this study a protocol for blood serum analysis was defined and the concentrations for Br, Ca, Cl, Fe, Na, Rb, Se and Zn were obtained by instrumental neutron activation analysis. Blood samples were collected from healthy elderly volunteers who were selected based on the SENIEUR protocol. Contamination of blood by the collection procedure was also evaluated and found negligible. The serum was separated by centrifugation, then freeze-dried and analyzed. Most of results obtained were within the acceptable value ranges used by physicians for normal population. The certified reference material, NIST SRM 1566b Oyster Tissue was analyzed for quality control.

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Abstract  

Neutron activation analysis was applied to assess trace element concentrations in brain tissues from normal (n = 21) and demented individuals (n = 21) of both genders aged more than 50 years. Concentrations of the elements Br, Fe, K, Na, Rb, Se and Zn were determined. Comparisons were made between the results obtained for the hippocampus and frontal cortex tissues, as well as, those obtained in brains of normal and demented individuals. Certified reference materials, NIST 1566b Oyster Tissue and NIST 1577b Bovine Liver were analyzed for quality of the analytical results.

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Journal of Thermal Analysis and Calorimetry
Authors: G. Bannach, R. Arcaro, D. Ferroni, A. Siqueira, O. Treu-Filho, M. Ionashiro, and E. Schnitzler

Abstract  

Thermogravimetry (TG), differential thermal analysis (DTA), differential scanning calorimetry (DSC) as well as X-ray diffraction powder (DRX) patterns and Fourier transformed infrared spectroscopy (FTIR) were used to study ketoprofen, ibuprofen, and naproxen. The chemical or physical properties of the studied compounds were established and when possible by X-ray powder diffractometry and/or infrared spectroscopy were used. In this investigation, quantum chemical approach was used to determine the molecular structures using Becke three-parameter hybrid method and the Lee–Yang–Par (LYP) correlation functional. The performed molecular calculations in this work were done using the Gaussian 03 routine. Theoretical calculations help in interpretations of FTIR spectra supplying structural and physicochemical parameters.

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Abstract  

Thermogravimetry technique is useful to determine the thermal stability of vegetable oils. In this paper some vegetable oils obtained from brazilian Cerrado native plants were studied based on their high oleic acid content. Amburana, baru and pequi pulp oils presented higher yield of extraction compared to soybean oil. The thermal stability of oils in nitrogen was very close hence their fatty acid composition was very similar. Amburana and baru oils have major amount of unsaturated fatty acids, especially linoleic acid and pequi pulp oil has the highest short chain fatty acid content which can explain its lowest thermal stability in synthetic air.

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Journal of Thermal Analysis and Calorimetry
Authors: E. Schnitzler, G. Bannach, O. Treu-Filho, C. T. Carvalho, and M. Ionashiro

Abstract

Solid-state compounds of general formula ThL4·nH2O, where L represents 2-methoxybenzylidenepyruvate and 2-methoxycynamylidenepyruvate, were synthesized. Complexometric titrations with EDTA, thermogravimetry (TG), differential thermal analysis (DTA), X-ray powder diffractometry, elemental analysis (EA), and infrared spectroscopy have been employed to characterize and to study the thermal behavior of these compounds in dynamic air atmosphere. The results led to informations about the composition, dehydration, crystallinity, and thermal decomposition of the isolated compounds. The performed molecular calculations in this study were done using the Gaussian 03 routine. Theoretical calculations help in interpretations of FT-IR spectra supplying structural and physicochemical parameters.

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Abstract  

Solid-state compounds of general formula LnL3⋅ nH2O, where Ln represents heavier lanthanides and yttrium and L is 2-chlorobenzylidenepyruvate, have been synthesized. Chemical analysis, simultaneous thermogravimetry-differential analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, elemental analysis and infrared spectroscopy have been employed to characterize and to study the thermal behaviour of these compounds in dynamic air atmosphere. On heating these compounds decompose in four (Gd, Tb, Ho to Lu, Y) or five (Eu, Dy) steps. They lose the hydration water in the first step and the thermal decomposition of the anhydrous compounds up to 1200C occurs with the formation of the respective oxide, Tb4O7 and Ln2O3 (Ln=Eu, Gd, Dy to Lu and Y) as final residue. The dehydration enthalpies found for these compounds (Eu, to Lu and Y) were: 65.77, 55.63, 86.89, 121.65, 99.80, 109.59, 131.02, 119.78, 205.46 and 83.11 kJ mol-1, respectively.

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Acetaminophen (AAP), acetylsalicylic acid (ASA) and dipyrone (DIP) are antipyretic and analgesics drugs that have wide use in health sciences. Some drugs can modify the labeling of blood elements with technetium-99m (99mTc). This work has evaluated the effect of AAP, ASA and DIP on the labeling of the blood elements with 99mTc. Blood was incubated with different concentrations of the drugs before the 99mTc-labeled process. Plasma (P), blood cells (BC), insoluble (IF-P, IF-BC) and soluble (SF-P, SF-BC) fractions were separated and percentage of radioactivity (%ATI) in each fraction was determined. Data have shown that the antipyretic drugs used in this study did not significantly modify the fixation of 99mTc on the blood elements when the experiments were carried out with the doses usually used in human beings. Although the experiments were carried out with rats, it is possible to suggest that AAP, ASA or DIP should not interfere with the procedures in nuclear medicine involving the labeling of blood elements with 99mTc

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. P. Felicissimo, J. L. Peixoto, M. S. Barbosa, G. Demortier, J.-J. Pireaux, and U. P. Rodrigues-Filho

Summary  

The purpose of this study was to investigate by PIXE and PIGE the pottery from two archaeological sites located near the Brazil-Bolivia border in Pantanal, an area of natural preservation. The region was inhabited by ancient Amerindian tribes long before the Latin America colonization period and a deep understanding of their environment, cultural attributes and interconnections can only be achieved based on the study of archaeological findings. Multivariate statistical procedures were used to determine similarities and correlations between the analyzed samples and to indicate possible sources of raw material provenience. The results showed that traces of Cr, Cu and Ti and Na/Si and Mg/Si counting ratios were important to distinguish sherds from the archaeological sites MS-CP-71 and MS-CP-61.

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Journal of Thermal Analysis and Calorimetry
Authors: A. G. Souza, I. P. Silva Filho, J. C. O. Santos, L. M. Nunes, I. M. G. Santos, L. E. B. Soledade, and M. M. Conceiçăo
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