DERLY AUGUSTO DIAS
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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.Dissertação IPEN-doc 25659 Estudo in vitro dos efeitos da radiação ionizante em tecido ósseo por espectroscopia vibracional2018 - DIAS, DERLY A.O tecido ósseo fornece sustentação e estrutura ao corpo, serve de alavanca para a função motora dos músculos esqueléticos, protege os órgãos internos, tem papel fundamental na fisiologia e está sujeito aos efeitos danosos da radiação ionizante. A estimativa para o Brasil, biênio 2016-2017, aponta a ocorrência de cerca de 600 mil casos novos de câncer e cerca de 8.000 solicitações de tecido ósseo para enxerto. Neste sentido a caracterização do tecido ósseo irradiado, através de técnicas de espectroscopia vibracional, pode ser uma importante ferramenta para compreender quais componentes são afetados e o quanto as diferentes doses de radiação ionizante alteram sua estrutura molecular. A técnica de espectroscopia ATR-FTIR (Attenuated Total Reflection Fourier Transform Infrared Spectroscopy), que permite análises qualitativas e semi-quantitativas, foi utilizada para caracterizar o tecido ósseo. Foram coletadas 110 amostras de diferentes fêmures bovinos e irradiadas com doses de 0,002 kGy; 0,004 kGy; 0,07 kGy; 1 kGy, 10 kGy, 15 kGy, 25 kGy, 35 kGy, 50 kGy e 60 kGy em fonte de 60Co. A espectroscopia ATR-FTIR demonstrou-se eficaz na caracterização do tecido e é possível afirmar que a radiação ionizante alterou a estrutura bioquímica do tecido ósseo, em sua matriz orgânica independente da dose aplicada e inorgânica a partir de 10 kGy.Resumo IPEN-doc 25611 Effects of gamma irradiation on bovine bone microhardness and molecular structure2018 - DIAS, DERLY A.; PEREIRA, DAISA L.; GOMES, GABRIELA V.; SUGAHARA, VANESSA M.L.; ZAMATARO, CLAUDIA B.; ZEZELL, DENISE M.; MATHOR, MONICA B.The skeletal systems is a complex mixed compounds, organic and inorganic, that should present a mechanical resistance to perform functions as protection of the vital organs and load distribution. Gamma radiation is an ionizing radiation that comes from radioative sources or X-ray generator and it is commonly used in health establishments such as radio diagnostic exams, radiotherapy and sterilization of allograft. The characterization of the irradiated bone tissue can be an important tool in the study of the components that are aÆected and how much each dose of ionizing radiation can alter its mechanical properties. This information will be very important in in vitro and ex vivo studies where sterilization of the bone material is necessary and may still be useful in understanding the eÆects on the bone tissue of patients undergoing short-term radiotherapy. For this, 110 samples of bovine femur diaphysis were randomized into 11 groups: G1- untreated (control); G2 to G11 were submitted to gamma irradiation (60Co Gammacel). Samples were polished before irradiation and submitted to a Knoop Microhardness Test to determine the hardness of bovine bone and Fourier transform Infrared spectroscopy (FTIR). Spectra were collected in the midinfrared range in Attenuated Total Reflectance (ATR) sampling mode associated whit PCA multivariate technique to evaluate the molecular changes in bone matrix. The microhardness analysis did not present a significant statistical diÆerence between the irradiated and control groups, showing that ionizing radiation did not aÆect the mechanical structure of the samples, on a micro scale. The results of FTIR with the PCA technique were eÆective in separating all groups, especially those irradiated with doses of 0.002 kGy, 10 kGy and 35 kGy. We conclude that ATR-FTIR spectroscopy associated with PCA is a good method to evaluate the biochemical changes promoted by ionizing radiation in bone matrix. It was observed that hardness was not altered by gamma irradiation and FTIR spectroscopy associated with PCA is a good method to analyze the changes in bone tissue submitted to ionizing radiation.Resumo IPEN-doc 25609 Molecular characterization of ex-vivo natural bovine dental enamel2018 - ZAMATARO, CLAUDIA B.; PEREIRA, DAISA L.; GOMES, GABRIELA V.; ALVES, NATHALIA Z.; CASTRO, PEDRO A.A.; DIAS, DERLY A.; ZEZELL, DENISE M.; SCAPIN, MARCOS A.Bovine teeth are widely used to infer results on a human population. Considering this, an analysis of the mineral content of bovine enamel, focusing the hidroxiapatite (HA), was carried out to evaluate the homogeneity of the sample universe for future experiments with laser irradiation as a substitute of human teeth enamel. Twelve samples of 5 x 5 mm bovine enamel were prepared and polished plane. The mineral content was calculated through surface microhardness (SMH) and morphology by scanning electron microscopy (SEM). Main molecular components of the enamel were analysed by Energy Dispersive X-ray Spectroscopy (EDS). Surface microhardness is an indirect indicator of the mineral content of the samples, which was 258.2 (38.8) KHN. The compounds present in the samples, the values of Calcium and Phosphate oxides and the ration Ca/P were analizes. As expected Phosphorus pentoxide and Calcium oxide were the main constituent of the samples (57.4 to 59.9%). The CaO/P2O5 ratio shows a variation with linear correlation (R2 = 1). The elemental ratio (Ca/P) shows a change in the elemental content with linear correlation (R2 = 1). 30% of the samples presented Strontium oxide, 30% had Zirconium dioxide, 10% had Magnesium oxide and 40% had Silicon dioxide. All samples showed Sulfur trioxide, Iron trioxide and Chlorine. 10% did not shown Zinc oxide. 5% had Potassium oxide and Nickel oxide in its composition. The surface microhardness results, although only for the initial homogenization of the sample universe, showed a Knoop hardness number within a spectrum similar to that of natural hydroxyapatite of human origin. The EDS results show that bovine enamel hydroxyapatite present great similarity with that from human enamel hydroxyapatite from the point of view of chemical composition. These results corroborate the use of bovine hydroxyapatite in substitution of hydroxyapatite of human origin. Despite the inter-species similarity, it is possible to note that in the same species the composition of hydroxyapatite varies. In the bovine species, the feeding, the period of formation of the dental germs and the origin are more standardized and controlled than in humans. Nevertheless, it is possible to notice a variation of the components elements of bovine dental enamel, and it is necessary to restrict an interval of hardness and Ca/P values to homogenise the samples properties for use in any experiment.Resumo IPEN-doc 24937 Biochemical evaluation of bone submitted to ionizing radiation by ATR-FTIR spectroscopy2017 - CASTRO, PEDRO A.A. de; DIAS, DERLY A.; VELOSO, MARCELO N.; ZEZELL, DENISE M.FTIR spectroscopy associated with PC-LDA was able to discriminate bone samples receiving different ionizing radiation doses (0,01 kGy, 1 kGy, 15 kGy), showing potential to the use of phosphate vibrational modes as a dose marker. OCIS codes: (170.4580) Medical optics and biotechnology – Optical diagnostics for medicine; (170.6510) Medical optics and biotechnology – Spectroscopy, tissue diagnostics; (170.1580) Medical optics and biotechnology – Chemometrics.Artigo IPEN-doc 24128 Effects of gamma irradiation on microhardness and Fourier Transform infrared spectroscopy of bovine bone2017 - DIAS, DERLY A.; PEREIRA, DAISA L.; GOMES, GABRIELA V.; SUGAHARA, VANESSA M.L.; MATHOR, MONICA B.; ZEZELL, DENISE M.Artigo IPEN-doc 24103 Characterization of ionizing radiation effects on bone using Fourier Transform Infrared Spectroscopy and multivariate analysis of spectra2017 - CASTRO, PEDRO A.A. de; DIAS, DERLY A.; ZEZELL, DENISE M.Ionizing radiation has been used as an important treatment and diagnostic method for several diseases. Optical techniques provides an efficient clinical diagnostic to support an accurate evaluation of the interaction of radiation with molecules. Fourier-transform infrared spectroscopy coupled with attenuated total reflectance (ATR-FTIR) is a label-free and nondestructive optical technique that can recognize functional groups in biological samples. In this work, 30 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 Cobalt-60 Gammacell Irradiator source at doses of 0.1 kGy, 1 kGy, whereas the fragments exposed to dose of 15 kGy was irradiated in a multipurpose irradiator of Cobalt-60. Spectral data was submitted to principal component analysis followed by linear discriminant analysis. Multivariate analysis was performed with Principal component analysis(PCA) followed by Linear Discriminant Analysis(LDA) using MATLAB R2015a software (The Mathworks Inc., Natick, MA, USA). We demonstrated the feasibility of using ATR-FTIR spectroscopy associated with PCA-LDA multivariate technique to evaluate the molecular changes in bone matrix caused by different doses: 0.1 kGy, 1 kGy and 15 kGy. These alterations between the groups are mainly reported in phosphate region. Our results open up new possibilities for protein monitoring relating to dose responses.Resumo IPEN-doc 22904 Semi-quantitative analysis in FTIR: exploring and testing four methods for band area calculation in bone2016 - CASTRO, P.A.A.; BENETTI, C.; DIAS, DERLY A.; ZEZELL, D.M.