DALTON GIOVANNI NOGUEIRA DA SILVA

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  • Artigo IPEN-doc 30196
    X-ray investigation of graphic art
    2023 - SILVA, ANA C.K. de S.; ZAMBONI, CIBELE B.; SILVA, DALTON G.N. da
    X-rays produced by electron ionization provide an analytical tool that can assist investigations in the field of Artistic and Cultural Heritage. In this study, the technique of Energy Dispersive X-ray Fluorescence (EDXF) was employed to investigate collections of postcards from the 1960s produced in Brazil, London and Uruguay. The collections belong to private collections and were made available for analysis at the Radiation Spectroscopy and Spectrometry Laboratory of the Institute for Nuclear and Energy Research (IPEN). This technique is non-destructive and allows the identification of chemical elements present in the different chemical formulations used in the printing industries of each country in the process of preparing postcards. This information allows tracing their origin and identifying copies/fakes, which enables their cataloging and registration for exhibition, as well as providing subsidies for conservators and restorers regarding the preservation and storage of these artistic materials.
  • Artigo IPEN-doc 26145
    Progress and trends for radiation applications in clinical practice
    2019 - ZAMBONI, CIBELE B.; METAIRON, SABRINA; MEDEIROS, JOSE A.G. de; SILVA, DALTON G.N. da; TASSO, ORION G.
    In this study, we intend to optimize the use of equipment based on the X-Ray Fluorescence technology to perform ions dosage in body fluids. This procedure can be an efficient alternative for clinical diagnosis, mainly in underserved regions of Brazil with the deficit of medical care in the hospitals. In addition, this procedure has potential use when the biological material is scarce, case of the pediatric practice in newborns and premature infants (blood collection is the main cause of transfusions) as well as in Hemodialysis units which requires several biochemical tests (before and after dialysis).
  • Artigo IPEN-doc 24352
    Iron determination in whole blood samples of dystrophic mouse strains using X-Ray fluorescence spectrometry
    2017 - METAIRON, SABRINA; ZAMBONI, CIBELE B.; GIOVANNI, DALTON N. da S.; SUZUKI, MIRIAM F.; BUENO JUNIOR, CARLOS R.; RIZZUTTO, MARCIA de A.
    Several diseases can be monitored by assessing the variation of specific ion concentration in body fluids. This study proposes an alternative analysis, based on the X-ray fluorescence spectrometry technique, for the investigation of iron (Fe concentration determination) in whole blood of the dystrophic animal models. We performed blood analyses from three different strains with Muscular Dystrophy (Dmdmdx/ J, SJL/J and A/J) and from healthy (C57BL/6J) mice strain adopted as the control group. The results emphasize that iron levels in whole blood male samples of SJL/J and A/J are significantly higher. Related to the gender for Dmdmdx/J and SJL/J mouse strains the comparison emphasizes that iron level increase for males. The study of Fe behavior in whole blood mice samples with muscular dystrophy contributes to its diagnosis, providing a better understanding of this disease.
  • Resumo IPEN-doc 23901
    Iron determination in whole blood samples of dystrophic mice strains using X-ray fluorescence spectrometry
    2017 - SILVA, DALTON G.N. da; METAIRON, SABRINA; ZAMBONI, CIBELE B.; SUZUKI, MIRIAM F.; BUENO JUNIOR, CARLOS R.; RIZZUTTO, MARCIA de A.
    The use of alternative analytical techniques to investigate specific electrolytes in body fluids has increased in past years with the goal of adding advantages and simplifications, compared to the procedures used in conventional clinical practice. Specifically, in this study, a portable X-ray spectrometer (PXRFS) from Amptek (model X-123 SDD) with Ag X-ray mini-tube has been employed for the whole blood iron measurements in mice species with Muscular Dystrophy (Dmdmdx/J, SJL/J and A/J). The term whole blood refers to solid (cells) and liquid (plasma) components in blood. Usually the conventional procedures for clinical tests are performed in serum using samples of 0.5 to 1.0 mL. However, when the biological material is scarce (case of small size animal model, i.e. mice), the possibility to use whole blood became a fascinating alternative for clinical practice: the Energy Dispersive X-Ray Fluorescence (EDFRX) analyses, using PXRFS, can be done using 50 μL (the total body blood in mice is around 1.0 mL). In this study, we investigated whole blood samples of dystrophic mice strains, a genetic disease that cannot be reversed. In this investigation, twenty samples were investigated. The blood samples were obtained from Jackson Laboratory (Maine, USA) and further inbred at IPEN. The whole blood was collected by the retro–orbital venous plexus and immediately transferred to filter paper (Whatman n41), prior to its coagulation. No anticoagulants or reagents have been used to prevent interference on the results. This procedure simplify the preparation and conservation of biological samples: it is not a destructive procedure and the sample does not need refrigeration. The collection was performing according to the rules approved by Animal Research Ethics Committee (087/99). A comparative study between EDXFX and INAA (Instrumental Neutron Activation Analysis) data was also carried out and the results are in good agreement. This alternative procedure was capable, in a few minutes, to determine whole blood Fe concentrations higher than 6.5 mgL-1, without chemical digestion using direct and non-destructive analysis. The study of Fe behavior in whole blood samples of mice with muscular dystrophy contributes to its diagnosis.