Junho 2019 vol. 2 num. 1 - Encontro Anual da Biofísica 2019

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BIOPHYSICS OF THE RADIATION CYTOGENETIC DAMAGE

BIOPHYSICS OF THE RADIATION CYTOGENETIC DAMAGE

Fernandes, Thiago de Salazar e ;

Artigo completo:

Biodosimetry is a well stablished method for estimating absorbed dose of radiation in different scenarios, such as for patients undergoing radiotherapy, for the staff occupationally exposed to ionizing radiation, in cases of nuclear reactor accidents. This method is based on the scoring of dicentric chromosomes, rings and acentric fragments in peripheral blood lymphocytes, especially in cases when physical dosimetry was not performed. This allows the medical team to access the absorbed dose, helping the planning of therapy of such individuals. For doses higher than 1 Gy, medical team can plan the therapy such as bone marrow transplant. For doses lower than 1 Gy, doctors can estimate the risks of stochastic diseases, such as cancer. It is of great importance to standardize the protocols of biodosimetry. This can be done by the comparison between papers published in the specialized literature. However, these reports involve different scenarios, what cause a great variability and different interpretations among investigators, such as: What was the time passed between irradiation and blood collection? What was the scenario: chronic, protracted, acute or partial irradiation? What time Colcemid should be added during cell culture? Is there any biological approach that could make possible to detect the real fraction of cells exposed containing dicentrics? Is there a quicker and easy-to-perform method for screening radiation human exposures in mass casualties? There is no consensus yet for all these questions. There are many works in the scientific literature discussing most of these questions, and here it will be discussed the calculations of absorbed dose depending on the context of radiation exposure, and a possible methodological solution for some scenarios and screening, based on the understanding of the fractal high order chromatin organization.

Artigo completo:

Biodosimetry is a well stablished method for estimating absorbed dose of radiation in different scenarios, such as for patients undergoing radiotherapy, for the staff occupationally exposed to ionizing radiation, in cases of nuclear reactor accidents. This method is based on the scoring of dicentric chromosomes, rings and acentric fragments in peripheral blood lymphocytes, especially in cases when physical dosimetry was not performed. This allows the medical team to access the absorbed dose, helping the planning of therapy of such individuals. For doses higher than 1 Gy, medical team can plan the therapy such as bone marrow transplant. For doses lower than 1 Gy, doctors can estimate the risks of stochastic diseases, such as cancer. It is of great importance to standardize the protocols of biodosimetry. This can be done by the comparison between papers published in the specialized literature. However, these reports involve different scenarios, what cause a great variability and different interpretations among investigators, such as: What was the time passed between irradiation and blood collection? What was the scenario: chronic, protracted, acute or partial irradiation? What time Colcemid should be added during cell culture? Is there any biological approach that could make possible to detect the real fraction of cells exposed containing dicentrics? Is there a quicker and easy-to-perform method for screening radiation human exposures in mass casualties? There is no consensus yet for all these questions. There are many works in the scientific literature discussing most of these questions, and here it will be discussed the calculations of absorbed dose depending on the context of radiation exposure, and a possible methodological solution for some scenarios and screening, based on the understanding of the fractal high order chromatin organization.

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DOI: 10.5151/biofisica2019-15

Referências bibliográficas
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Como citar:

Fernandes, Thiago de Salazar e; "BIOPHYSICS OF THE RADIATION CYTOGENETIC DAMAGE", p. 51-53 . In: Anais do Encontro Anual da Biofísica 2019. São Paulo: Blucher, 2019.
ISSN 2526--607-1, DOI 10.5151/biofisica2019-15

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