Study of the in vitro survival behavior of SiHa cells irradiated with an Ir-192 source of BQT-HDR

ilstraciones, fotografías, graficasEn el presente trabajo se evaluó la supervivencia de la línea celular SiHa al ser irradiada con una fuente radiactiva de Iridio 192 (Ir-192), para esto se planteó y desarrolló la siguiente metodología. En la primera fase se realizaron los controles de calidad asociados a la actividad de la fuente, los tiempos de tránsito y la verificación de la dosis a entregar. Se verificó la actividad de la fuente obteniendo un error del 0.9104% y el tiempo de tránsito con un error de 3.15%, además de verificar y corregir una subdosificación del 15% de la dosis al momento de irradiar los cultivos celulares. En la segunda fase de la metodología se obtuvo una curva de supervivencia celular a partir del ensayo por MTT, para diferentes dosis irradiadas, obteniendo un comportamiento exponencial decreciente acorde a lo mostrado en la literatura; se realizaron también ensayos clonogénicos para determinar la fracción de supervivencia de las células, pero los resultados no fueron concluyentes. En la tercera y última fase se irradiaron cultivos celulares con dos de los esquemas de irradiación más usados en los procedimientos de braquiterapia del Instituto Nacional de Cancerología. El Esquema 1 con dosis de 5.5 Gy en 5 fracciones y el Esquema 2 con dosis de 7 Gy en 4 fracciones, obteniendo una menor supervivencia celular con el Esquema 2. (Texto tomado de la fuente)In the present work, the survival of the SiHa cell line when irradiated with a radioactive source of Iridium 192 (Ir-192) was evaluated, for which the following methodology was proposed and developed. In the first phase, quality controls associated with the activity of the source, transit times and verification of the dose to be delivered were carried out. The activity of the source was verified, obtaining an error of 0.9104% and the transit time with an error of 3.15%, in addition to verifying and correcting an underdosage of 15% of the dose at the time of irradiating the Cell cultures. In the second phase of the methodology, a cell survival curve was obtained from the MTT assay, for different irradiated doses, obtaining a decreasing exponential behavior according to what is shown in the literature; clonogenic assays were also performed to determine the survival fraction of the cells, but the results were inconclusive. In the third and final phase, cell cultures were irradiated with two of the most widely used irradiation schemes in brachytherapy procedures at the National Institute of Cancerology. Scheme 1 with a dose of 5.5 Gy in 5 fractions and Scheme 2 with a dose of 7 Gy in 4 fractions, obtaining a lower cell survival with Scheme 2.MaestríaMagíster en Física MédicaRadiobiologí

The ARTI Framework: Cosmic Rays Atmospheric Background Simulations

ARTI is a complete framework intended to simulate the expected signals produced by the interaction of the secondary particles inside any Water Cherenkov Detector, WCD. ARTI comprises a simulation sequence by integrating three different simulation tools: a) magnetocosmics, to account for the geomagnetic field effects on the primary flux; b) CORSIKA, to simulate the atmospheric showers originated on the complete flux of cosmic rays in the energy range of interest and, thus, to estimate the expected flux of secondary particles at the site; and c) Geant4, for simulating the WCD detectors response to this secondary flux. In this work, we show the usage of the ARTI framework by calculating the expected flux of signals at eight sites from the Latin American Giant Observatory, LAGO. This covers a wide range of altitudes and geomagnetic rigidity cut-offs. This shows it is possible to estimate the secondary particle flux originated by cosmic rays at any location in the world. This flux could be used either to be injected into WCDs, to estimate the footprint generated by Gamma-Ray Burst events, or over a geological structure in muography applications.Comment: 10 page

Study of the in vitro survival behavior of SiHa cells irradiated with an Ir-192 source of BQT-HDR

ilstraciones, fotografías, graficasEn el presente trabajo se evaluó la supervivencia de la línea celular SiHa al ser irradiada con una fuente radiactiva de Iridio 192 (Ir-192), para esto se planteó y desarrolló la siguiente metodología. En la primera fase se realizaron los controles de calidad asociados a la actividad de la fuente, los tiempos de tránsito y la verificación de la dosis a entregar. Se verificó la actividad de la fuente obteniendo un error del 0.9104% y el tiempo de tránsito con un error de 3.15%, además de verificar y corregir una subdosificación del 15% de la dosis al momento de irradiar los cultivos celulares. En la segunda fase de la metodología se obtuvo una curva de supervivencia celular a partir del ensayo por MTT, para diferentes dosis irradiadas, obteniendo un comportamiento exponencial decreciente acorde a lo mostrado en la literatura; se realizaron también ensayos clonogénicos para determinar la fracción de supervivencia de las células, pero los resultados no fueron concluyentes. En la tercera y última fase se irradiaron cultivos celulares con dos de los esquemas de irradiación más usados en los procedimientos de braquiterapia del Instituto Nacional de Cancerología. El Esquema 1 con dosis de 5.5 Gy en 5 fracciones y el Esquema 2 con dosis de 7 Gy en 4 fracciones, obteniendo una menor supervivencia celular con el Esquema 2. (Texto tomado de la fuente)In the present work, the survival of the SiHa cell line when irradiated with a radioactive source of Iridium 192 (Ir-192) was evaluated, for which the following methodology was proposed and developed. In the first phase, quality controls associated with the activity of the source, transit times and verification of the dose to be delivered were carried out. The activity of the source was verified, obtaining an error of 0.9104% and the transit time with an error of 3.15%, in addition to verifying and correcting an underdosage of 15% of the dose at the time of irradiating the Cell cultures. In the second phase of the methodology, a cell survival curve was obtained from the MTT assay, for different irradiated doses, obtaining a decreasing exponential behavior according to what is shown in the literature; clonogenic assays were also performed to determine the survival fraction of the cells, but the results were inconclusive. In the third and final phase, cell cultures were irradiated with two of the most widely used irradiation schemes in brachytherapy procedures at the National Institute of Cancerology. Scheme 1 with a dose of 5.5 Gy in 5 fractions and Scheme 2 with a dose of 7 Gy in 4 fractions, obtaining a lower cell survival with Scheme 2.MaestríaMagíster en Física MédicaRadiobiologí

The ARTI framework: cosmic rays atmospheric background simulations

ARTI is a complete framework designed to simulate the signals produced by the secondary particles emerging from the interaction of single, multiple, and even from the complete flux of primary cosmic rays with the atmosphere. These signals are simulated for any particle detector located at any place (latitude, longitude and altitude), including the real-time atmospheric, geomagnetic and detector conditions. Formulated through a sequence of codes written in C++, Fortran, Bash and Perl, it provides an easy-to-use integration of three different simulation environments: MagnetoCosmics, CORSIKA and Geant4. These tools evaluate the geomagnetic field effects on the primary flux and simulate atmospheric showers of cosmic rays and the detectors’ response to the secondary flux of particles. In this work, we exhibit the usage of the ARTI framework by calculating the total expected signal flux at eight selected sites of the Latin American Giant Observatory: a cosmic ray Observatory all over Latin America covering a wide range of altitudes, latitudes and geomagnetic rigidities. ARTI will also calculate the signal flux expected during the sudden occurrence of a gamma-ray burst or the flux of energetic photons originating from steady gamma sources. It also compares these fluxes with the expected background when they are detected in a single water Cherenkov detector deployed in a high-altitude site. Furthermore, by using ARTI, it is possible to calculate in a very precise way the expected flux of high-energetic muons and other secondaries at the ground level and to inject them through geological structures for muography applications.SCOPUS: ar.jinfo:eu-repo/semantics/publishe