PEDRO ARTHUR AUGUSTO DE CASTRO
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Artigo IPEN-doc 29344 Bone as a biomarker for detecting low dose of ionizing radiation2022 - CASTRO, PEDRO A.A. de; DIAS, DERLY A.; VELOSO, MARCELO N.; ZEZELL, DENISE M.FTIR spectroscopy was able to discriminate bone samples receiving low-dose ionizing radiation doses (0.002 kGy, 0.004 kGy, 0.007 kGy), offering valuable insights in view of the understanding of radiation dose response in biological systems.Resumo IPEN-doc 28974 Chemometric analysis of bone dose response2022 - CASTRO, PEDRO A.A. de; DIAS, DERLY A.; ZEZELL, DENISE M.The use of ionizing radiation for treatment and diagnosis of many diseases has been well documented. The health effects of ionizing radiation improved patient care, however, incorrect handling of radiation technology may pose potential health risks. In light of this, Fourier-transform infrared spectroscopy combined with attenuated total reflectance (ATR-FTIR) offers a nondestructive, label-free technique for identifying functional groups in biological samples. In this work, fragments of bone were collected from bovine femur diaphysis. Samples were cut and polished until 1 cm x 1 cm x 1 mm, which were then stored properly in the refrigerated environment. Samples irradiation was performed with a multipurpose irradiator of Cobalt-60 at doses of 15 kGy and 25 kGy.Spectral data was submitted for the second derivative. Thereafter, the amplitude of the second derivative was organized for hierarchical clustering in conjunction with a heatmap. In order to carry out the chemometric analyses, all procedures were performed using MATLAB (The Mathworks Inc., Natick, MA, USA). Based on these results, an examination of the cluster heatmap reveals that the unique behavior for each group which may be correspond to the ionizing radiation change in the spectra. Hence, these findings suggest new possibilities for spectral monitoring of dose responses.Artigo IPEN-doc 28871 Assessment of bone dose response using ATR-FTIR spectroscopy2022 - CASTRO, PEDRO A.A. de; DIAS, DERLY A.; DEL-VALLE, MATHEUS; VELOSO, MARCELO N.; SOMESSARI, ELIZABETH S.R.; ZEZELL, DENISE M.The health care application of ionizing radiation has expanded worldwide during the last several decades. While the health impacts of ionizing radiation improved patient care, inaccurate handling of radiation technology is more prone to potential health risks. Therefore, the present study characterizes the bone dose response using bovine femurs from a slaughterhouse. The gamma irradiation was designed into low-doses (0.002, 0.004 and 0.007 kGy) and high-doses (1, 10, 15, 25, 35, 50 and 60 kGy), all samples received independent doses. The combination of FTIR spectroscopy and PLS-DA allows the detection of differences in the control group and the ionizing dose, as well as distinguishing between high and low radiation doses. In this way, our findings contribute to future studies of the dose response to track ionizing radiation effects on biological systems.