PAULO ROBERTO DOMINGUES DE SOUZA

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  • Resumo IPEN-doc 26912
    Methodology for in vivo dosimetry using TLD-100 for radiotherapic treatment
    2017 - RODRIGUES, B.T.; SOUZA, P.D. de; SOUZA, C.D. de; ROSTELATO, M.C.M.; ZEITUNI, C.; NOGUEIRA, B.R.; MARQUES, J. de O.; SOUZA, A.S. de
    Cancer is a public health problem that affects approximately 27 million people worldwide. The most common type in Brazil among men is prostate cancer with 61 thousand cases. There are two forms of radiotherapy treatments that can be used: teletherapy and brachytherapy. Before starting the teletherapy treatment, a planning is done that makes the acquisition of the anatomical information of the patient to then classify the areas of interest. Dosimetry is performed as a quality control to ensure that the calculated dose is equal to that received by the patient. In vivo dosimetry acts as an independent measurement and this work aims at comparing the dosimetry performed using thermoluminescent dosimeters (LiF: Mg, Ti - TLD - 100) with dose values calculated in the planning system (TPS). Methods: All dosimeters were prepared to be used in an anthropomorphic phantom. A selection of dosimeters, 50 micro TLD’s, selected after heat treatment, were then irradiated and a reading was made. A case planned by TPS was selected and compared the dosimetry performed in an anthropomorphic phantom for the same case. Results: All values obtained were within the deviation ( 5%) allowed by the protocol. The results of this work will help to implement a new quality program in the Radiotherapy Service at Hospital das Cl ınicas de S~ao Paulo. Conclusion: The accurate dosimeter selection provided a feasible and reliable evaluation that enabled the comparison.
  • Artigo IPEN-doc 26316
    Gold nanoparticle applied to brachytherapy
    2019 - GONZALEZ, ANDREZA A.D.C.C.; SOUZA, CARLA D.; ARCOS, WILMER A.; RODRIGUES, BRUNA T.; DOMINGUES, PAULO R.; SPINOSA, TATYANA B.; ROSTELATO, MARIA E.C.M.
    Cancer is a global public health problem, that consists in a disease is characterized by the uncontrolled growth of anomalous cells that impair the functioning of the body. One of the treatments for cancer is the brachytherapy. This technique a non-invasive treatment in which the radiation is placed close or in contact with the region to be treated, brachytherapy may save the healthy tissues and consequently reduces the amount of side effects. An unexplored strand is nanobrachytherapy, that unites the advantages of brachytherapy with the small size in the nanoparticle (NP), resulting in an even less invasive treatment. Nanotechnology is the science that studies the properties of nanometric materials with the aim of creating new materials with different properties of interest. In view of the synthesis of the NP and their applicabilities, there is a fundamental role that is made to coatings, which have the function of avoiding the aggregation of particles, stabilize and also control their functional properties. Besides being able to add molecules of interest, such as antibiotics and anti-inflammatories. Among the range of coatings, the most outstanding are polyethylene glycol (PEG). PEG improves the surface properties of NP and presents high stability under biomedical conditions. The NP have their size controlled, which facilitates their penetration into the vasculature, in addition to being a non-toxic coating. After the synthesis of gold nanoparticles (Au-NP) was developed, PEG were successfully incorporated into the surface. Incorporation was confirmed by DLS, FT-IR and HRTEM.
  • Artigo IPEN-doc 26303
    Calibration methodology and selection of TLD – 100
    2019 - LUCCA, LUIZA V.G. de; RODRIGUES, BRUNA T.; SOUZA, PAULO R.D. de; MACHADO, LUCAS K.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
    In Brazil, it is estimated that for the biennium 2018 2019, that occurred 600 thousand of new cases of cancer for each year and lung cancer is the most common of all malignant tumors. Radiotherapy acts as a form of treatment from which come two basic modalities for the treatment of cancer: teletherapy and brachytherapy. In teletherapy is used a linear accelerator to make the application and before starting the treatment is carried out a planning that makes the acquisition of all anatomical information of the patient and then the classification of areas of interest in the patient. All planning prior to initiation undergoes a quality control dosimetry, which ensures that the dose prescribed in the planning will be delivered accurately in the treatment of the patient. In radiotherapy the dosimetry is applied as an independent measurement and this work has the objective of comparing the dosimetric plan of lung cancer in adjacent organs in this case the organ of risk is the heart with dose values calculated in the planning system (TPS) using an anthropomorphic phanton. All dosimetry was performed with thermo luminescent dosimeters (Lif: Mg,Ti TLD 100). We selected 50 TLDs that underwent a calibration process with thermal treatment, irradiation and reading. All the dosimeters passed through the reader in order to quantify its reading. The TLDs chosen were those that obtained coefficients of variation of less than 5% for three cycles of irradiation, in order to prove the methodology used for the thermal treatment, reading and calibration of dosimeters.
  • Resumo IPEN-doc 26024
    Evaluation of dose received in adjacent organs in the dosimetric plan of lung cancer
    2018 - SOUZA, PAULO R.D. de; RODRIGUES, BRUNA T.; MACHADO, LUCAS K.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.