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Abstract  

Monte Carlo calculations were done to simulate the decay of80mBr in order to estimate the energies and distribution of Auger and Coster-Kronig electrons emitted in this de-excitation process. Results show that for an isolated atom, the average number of electrons emitted per decay is 6.926 and 8.016 for an atom in the condensed state. These values agree well with experimental results of Wexler and Anderson. The average calculated electron energies were 1122 eV and 991 eV with ranges of 8.02 A° and 6.71 A° in unit density matter for the isolated an condensed states, respectively. These results will be used to estimate localized energy deposition which will be correlated to the radiotoxic effects of80mBr-bromo-deoxyuridine as measured in experiments currently underway in our laboratory using cell cultures. Our aim is to assess the radiotoxicity of low energy, short range electrons for its eventual use in cancer therapy.

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Abstract  

A selective dopamine D1 antagonist, SCH 23390, is routinely labelled with C-11 at our institution for use in imaging dopamine D1 receptors in primate brain using positron emission tomography.However, little is known about the metabolism of this compound. In this report, a method is presented for the HPLC characterization of SCH 23390 and its possible metabolites in blood using a liquid-solid extraction technique. This procedure was applied to the analysis of blood samples collected at time intervals from rhesus monkeys after the injection of C-11-SCH 23390. About 4 minutes after injection, polar metabolite(s) were found in the circulation. However, the amounts detected would not be expected to interfere with the analysis of brain PET scans.

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Summary  

Major and trace elements were determined in serum of patients with chronic myelogenous leukemia (CML) using total reflection X-ray fluorescence induced by synchrotron radiation (SRTXRF). CML affects 1 to 2 people per 100,000 and accounts for 7-20% cases of leukemia. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Br and Rb. Using analysis of variance (ANOVA) it was observed that the contents of the P, S, Ca, Cr, Mn, Fe, Cu and Rb elements differed significantly at a = 0.05 between groups of healthy subjects and CML patients and also genders (males and females).

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Moreira, A. E. S. Vives, O. L. A. D. Zucchi, E. F. O. de Jesus, V. F. Nascimento Filho, and S. M. B. Brienza

Summary  

In this study the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn and Br in twenty-nine brands of national and international beers were determined by synchrotron radiation total reflection X-ray fluorescence analysis (SR-TXRF). The results were compared with the limits established by the Brazilian legislation and the nutritional values established by National Agricultural Library (NAL, USA). The measurements were performed at the X-Ray Fluorescence Beamline at Brazilian National Synchrotron Light Laboratory, in Campinas, São Paulo, Brazil, using a polychromatic beam for excitation. A small volume of 5 ml of beers containing an internal standard used to correct geometry effects was analyzed without pretreatment. The measuring time was 100 seconds and the detection limits obtained varied from 1 mg . l-1 for Mn and Fe to 15 mg . l-1 for P.

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Summary  

The study of trace element levels is of great importance due to their relevance in agingand several neurodegenerative diseases. This work compares the elemental concentrations in different postnatal ages and between the temporal cortex, entorhinal cortex and hippocampus from Wistar rats, using X-ray total reflection fluorescence with synchrotron radiation. Ten elements were determined in brain samples: Ti, Cr, Mn, Fe, Cu, Zn, (at trace level) and P, S, Cl and K (at major levels). The elements that increased with aging in cortical areas were: S, K, Fe, Cu and Zn. Ca and Zn levels decreased with advancing age in the hippocampus. In addition to this, Ti, Mn and Fe levels were more conspicuous in the entorhinal cortex.

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