JOÃO AUGUSTO MOURA

JOÃO AUGUSTO MOURA

(Fonte: Lattes)

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Possui graduação em Tecnologia em saúde pela Faculdade de Tecnologia de Sorocaba (2005). Mestrado em Tecnologia Nuclear pela Universidade de São Paulo (2009). Doutorado em Tecnologia Nuclear pela Universidade de São Paulo (2015). Tem experiência na área de Tecnologia Nuclear, com ênfase em produção de fontes para radioterapia. Atualmente trabalha em pesquisa e desenvolvimento no Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP). (Texto extraído do Currículo Lattes em 8 maio 2023)

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New core configuration for the fabrication of 125I radioactive sources for cancer treatment
2020 - SOUZA, CARLA D. de; ZEITUNI, CARLOS A.; FEHER, ANSELMO; MOURA, JOÃO A.; COSTA, OSVALDO L. da; ANGELOCCI, LUCAS V.; ROSTELATO, MARIA E.C.M.
In order to provide prostate brachytherapy treatment for more Brazilian men, IPEN is building a laboratory for the manufacture of radioactive sources. The new methodology for the production of iodine-125 seeds with yield 71.7% ± 5.3%. Points of importance were evaluated/discussed: photo-sensibility, reaction vial type, the substitution for iodine-131, pH, and solution volume. The surface was analyzed by FTIR and EDS. At the end, a Monte Carlo-MCNP6 simulation was performed to evaluate the TG-43 parameters.
Waste management protocols for Iridium-192 sources production laboratory used in cancer treatment
2016 - ROSTELATO, MARIA E.C.M.; SOUZA, CARLA D. de; SOUZA, DAIANE C.B. de; ZEITUNI, CARLOS A.; TIEZZI, RODRIGO; COSTA, OSVALDO L. da; RODRIGUES, BRUNA T.; MOURA, JOÃO A.; FEHER, ANSELMO; SORGATTI, ANDERSON; MOURA, EDUARDO S. de; MARQUES, JOSE R. de O.; SANTOS, RAFAEL M. dos; KARAM JUNIOR, DIB
Introduction: Brachytherapy is a form of treatment that uses radioactive seeds placed in contact or inside the region to be treated, maximizing the radiation dose inside the targeted areas. Iridium-192 is being used in brachytherapy since 1955. It presents emission energy in the “therapy region” (370keV) and is easily produced in a nuclear reactor (191Ir (n, γ) → 192Ir). Wires are an iridium-platinum alloy with 0.36 mm diameter and they can be cut in any needed length. They can be used in several types of cancer. The linear activity is between 1 mCi/cm (37 MBq/cm) and 4 mCi/cm (148 MBq/cm) with variations of 10% in 50 cm maximum. This activity values classified the treatment and low dose rate (0,4 à 2 Gy/h). The propose of this work is to present a waste management system in a cancer treatment radioactive sources production laboratory. Methodology and Results: The solid waste is previously characterized in the analysis phase. The contaminants are already known and they are insignificant due to their fast half- life. The iridium-192 half-life is 74.2 days, classified as very short half-life waste. The waste activity is adds to 8mCi (2.96x108 Bq) per wire. According to the CNEN-NN 6.08 standard, that presents the discharge levels, the limit is 1 kBq.kg-1 (2.7x10-5 mCi.kg-1). The radioactive waste generated during the I192 wires production has a weakly activity of 9.7 GBq.g-1. According to the standards, this activity is too high to be discarded into the environment. The waste must be managed following the ALARA principal using the R&R (retain e retard) system, that means, temporary storage and posterior discharge. Since every 4 months, maintenance is performed inside the hot cell used for production, the waste must be removed. Using the equation: 𝐴 = 𝐿 λ (1 − 𝑒−λt), the total calculated activity is 1.68 x 1016 Bq and 4.8 g mass at the end of each 4 months period. This amount is stored inside a shielding device that has 212.37 cm3 volume. The waste will take 9.8 years (calculated by 𝐴 = 𝐴0(𝑒−λt)) to decay to the discharge levels. To store 30 devices during 10 years, a space with 6,370 cm3 is necessary. The laboratory has enough space for this storage. Thus, the radioactive waste management can be performed through the R&R (retain and retard) system safely.
New methodology for binding Iodine-125 onto silver for brachytherapy sources manufacture
2017 - SOUZA, C.D. de; ROSTELATO, M.C.M.; CARDOSO, R.M.; ARAKI, K.; MOURA, J.
Purpose: Cancer is a major health care problem in Brazil and the world. The Brazil’s National Institute for Cancer estimates around 60,000 new prostate cancer cases for 2017. We are assembling a laboratory for production of iodine-125 sources used in prostate brachytherapy in Brazil, since the imported treatment is extremely expensive, thus only available in the private healthcare sector. There are several challenges when developing a laboratory to produce radioactive sources. From choosing a prototype to radiation safety, the task is enormous. The whole production line is full of new process and innovations. Among those, a new chemical reaction that deposit iodine-125 onto silver (core) was developed. This paper presents a new reaction for binding iodine-125 into a silver core. The fixation percentage was calculated by measuring the activity in an ionization chamber. This methodology will be implemented at the iodine-125 sources manufacture laboratory. Methods: Silver cores are washed with an etching solution (100% sulfuric acid) for 5 minutes with sonication. The cores were then placed in sodium sulfate for at least 3 days. They went from a silver matte to a black color. The reaction was allowed to proceed overnight. Each core was individually measured. Results: The yield was 69.2% 7.1%. Considering the silver attenuation is around 20% the results were consider satisfactory. Conclusion: By maximize the reaction yield, we will be able to generate a less costly product that will be available through our public healthcare.
Waste management protocols for iridium-192 sources production laboratory used in cancer treatment in Brazil
2017 - ROSTELATO, M.E.C.M.; SOUZA, D.C.B.; SOUZA, C.D.; ZEITUNI, C.A.; VICENTE, R.; COSTA, O.L.; RODRIGUES, B.T.; MOURA, J.A.; FEHER, A.; MOURA, E.S.; MARQUES, J.R.O.; CARVALHO, V.S.; NOGUEIRA, B.R.
Objective: The iridium-192 wired sources production results in radioactive waste that needs to follow the guidelines. The aim of this study is to do a radioactive waste management of wastes from iridium-192 sources production laboratory used in cancer treatment in Brazil. Methods: The wire is acquired in an alloy form with 80% platinum and 20% iridium encapsulated with 100%. Electronic microscopy, X-ray fluorescence, and posterior iridium neutron activation (to determine contaminants) are performed to ensure quality. A 50-cm twisted wire is placed in an aluminum tube. The tube is sealed and place inside the reactor irradiator system and is left for decay during 30 hours to wait for the others undesired activation products to decay. The wire is prepared for treatment with 48 cm length with 192 mCi maximum activity. All the equipment use inside the hot cell must be calibrated every four months. All the waste must be removed from the hot cell. Results: The solid waste is previously characterized in the analysis phase. The contaminants are already known and they are insignificant due to their fast half-life. The iridium-192 half-life is 74.2 days, classified as very short half-life waste. The reminiscent activity is 8mCi. Conclusion: The radioactive waste generated during the I192 wires production is solid, was a short half-life and a weakly activity of 9.7 GBq.g-1. According to the standards, this activity is too high to be discarded into the environment (limit 10 Bq.g-1). The waste must be managed by the R&R (retain e retard) system.
Brazil radioactive sources production for cancer treatment
2016 - ROSTELATO, MARIA E.; SOUZA, CARLA D.; ZEITUNI, CARLOS A.; MOURA, JOAO A.; MARQUES, JOSE R.O.; COSTA, OSVALDO L.; FEHER, ANSELMO; RODRIGUES, BRUNA T.; SOUZA, DAIANE C.B. de; PELEIAS JUNIOR, FERNANDO S.; SORGATTI, ANDERSON; MOSCA, RODRIGO; MOURA, EDUARDO S. de; ABREU, RODRIGO T.; SOUZA, RAQUEL V. DE; NOGUEIRA, BEATRIZ R.
The modality, known as brachytherapy, was performed in Brazil by only a hand full of hospitals at an extremely high cost. For producing new sources, five major areas must be considered: 1) source production: nuclear activation and/or radiochemical reaction; 2) welding; 3) Quality control: leakage tests; 4) Dosimetry and metrology; 5) Operational procedures; 6) validation studies. To perform all steps, a multidisciplinary team works together to overcome difficulties. - Iridium-192 pellets: In Brazil there are 140 machines with pellets that replacement every 5 years. Our new production line has assembly, welding and quality control hot cells. - Iridium-192 wires: Produced since 1999. The wire is activated at IPENs IEA-R1 reactor for 30 hours with 5x1013 n/cm-2.s-1 neutron flux resulting in 192 mCi maximum activity. - Iridium-192 seed: New seed for ophthalmic cancer treatment. The irradiation device presented 90% activity homogeneity. We are still testing in-vivo. - Iodine-125 seeds: Largely used in low dose brachytherapy. I-125 binding yield achieved with our new reaction was 80%; Laser welding presented 70% efficiency. Approved in all leakage tests. - Other ongoing projects: Veterinary brachytherapy, Waste management, Radionecrosis healing with laser, calibrations sources production, linear accelerator calculations for hospitals, sources with polymeric matrix Our Iodine-125 seeds will be available in 2018. All other projects are advancing. We will continue to develop new products hoping to help the Brazilian population fight against cancer. For producing new sources, five major areas must be considered: 1) source production: nuclear activation and/or radiochemical reaction; 2) welding; 3) Quality control:eakage tests; 4) Dosimetry and metrology; 5) Operational procedures; 6) validation studies. To perform all steps, a multidisciplinary team works together to overcome difficulties
Comparing different methods for radioactive iodine fixation intended for brachytherapy sources manufacture
2016 - SOUZA, CARLA D.; ROSTELATO, MARIA E.C.M.; ZEITUNI, CARLOS A.; PELEIAS JUNIOR, FERNANDO S.; BENEGA, MARCOS A.G.; MOURA, JOAO A.; FEHER, ANSELMO; COSTA, OSVALDO L.; TIEZZI, RODRIGO; RODRIGUES, BRUNA T.; SILVA, THAIS H. da; SORGATTI, ANDERSON; SOUZA, DAIANE C.B. de
Brachytherapy, a method of radiotherapy, is being extensively used in the early and intermediate stages of the illness. In this treatment, radioactive seeds are placed inside or next to the area requiring treatment, which reduces the probability of unnecessary damage to surrounding healthy tissues. Currently, the radioactive isotope iodine-125, fixated on silver substrate, is one of the most used in prostate brachytherapy. The present study compares several deposition methods of radioactive iodine on silver substrate, in order to choose the most suitable one to be implemented at the laboratory of radioactive sources production of IPEN. Three methods were selected: method 1 (test based on electrodeposition method, developed by David Kubiatowicz) which presented efficiency of 65.16%; method 2 (chemical reaction based on the method developed by David Kubiatowicz - HCl) which presented efficiency of 70.80%; method 3 (chemical reaction based on the method developed by Dr. Maria Elisa Rostelato) which presented efficiency of 55.80%. Based on the results, the second method is the suggested one to be implemented at the laboratory of radioactive sources production of IPEN.
Development and characterization of iridium-192 seeds for brachytherapy treatment of ocular tumors
2014 - PELLEIAS JUNIOR, F.S.; ZEITUNI, C.A.; SOUZA, C.D.; ROSTELATO, M.E.C.M.; MATTOS, F.R.; BENEGA, M.A.G.; RODRIGUES, B.T.; TIEZZI, R.; OLIVEIRA, T.B.; FEHER, A.; MOURA, J.A.; COSTA, O.L.
Evaluation of different reaction methods resulting in the formation of Agl125 for use brachytherapy sources
2014 - SOUZA, C.D.; PELLEIAS JUNIOR, F.S.; ROSTELATO, M.E.C.M.; ZEITUNI, C.A.; BENEGA, M.A.G.; TIEZZI, R.; MATTOS, F.R.; RODRIGUES, B.T.; OLIVEIRA, T.B.; FEHER, A.; MOURA, J.A.; COSTA, O.L.
Study and development of a iridium-192 seed for use in ophthalmic cancer
2014 - ROSTELATO, M.; SOUZA, C. de; PELEIAS JUNIOR, F.S.; ZEITUNI, C.A.; MATTOS, F.R.; BENEGA, M.A.G.; MOURA, J.A.; FEHER, A.; COSTA, O.L.
Study and development of a iridium-192 seed for use in ophthalmic cancer
2014 - ROSTELATO, M.; SOUZA, C. de; PELEIAS JUNIOR, F.S.; ZEITUNI, C.A.; MATTOS, F.R.; BENEGA, M.A.G.; MOURA, J.A.; FEHER, A.; COSTA, O.L.