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OBJECTIVES: To compare food insecurity (FI) in Chile before and during the COVID-19 pandemic according to different household types and vulnerability indicators. STUDY DESIGN: Longitudinal study based on two population-based surveys in Chile (CASEN 2017 and COVID 2020). METHODS: Descriptive analysis and multinomial regression models for FI through the Food Insecurity Experience Scale (FIES). RESULTS: FI levels increased significantly (P < 0.001) between 2017 (30%) and 2020 (49%). There was increased FI in all households, but especially in those with economically dependent persons (i.e. children, adolescents and older adults). Household vulnerability indicators showed a statistically significant relationship with FI both before and during the pandemic. The pandemic has resulted in new population groups experiencing FI. CONCLUSIONS: The COVID-19 pandemic has led to a significant increase in FI, which has also been seen in new population groups.
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COVID-19 , Pandemias , Adolescente , Idoso , Criança , Chile/epidemiologia , Estudos Transversais , Características da Família , Insegurança Alimentar , Abastecimento de Alimentos , Humanos , Estudos Longitudinais , SARS-CoV-2RESUMO
In this work we provide some information on the present status of accelerator-based BNCT (AB-BNCT) worldwide and subsequently concentrate on the recent accelerator technology developments in Argentina.
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Terapia por Captura de Nêutron de Boro/instrumentação , ArgentinaRESUMO
In the frame of accelerator-based BNCT, the (9)Be(d,n)(10)B reaction was investigated as a possible source of epithermal neutrons. In order to determine the configuration in terms of bombarding energy, target thickness and Beam Shaping Assembly (BSA) design that results in the best possible beam quality, a systematic optimization study was carried out. From this study, the optimal configuration resulted in tumor doses ≥40Gy-Eq, with a maximum value of 51Gy-Eq at a depth of about 2.7cm, in a 60min treatment. The optimal configuration was considered for the treatment planning assessment of a real Glioblastoma Multiforme case. From this, the resulted dose performances were comparable to those obtained with an optimized (7)Li(p,n)-based neutron source, under identical conditions and subjected to the same clinical protocol.
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Terapia por Captura de Nêutron de Boro/instrumentação , Boro/uso terapêutico , Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Aceleradores de Partículas/instrumentação , Radiometria/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Isótopos/uso terapêutico , Teste de Materiais , Nêutrons/uso terapêutico , Espalhamento de RadiaçãoRESUMO
The activity in accelerator development for accelerator-based BNCT (AB-BNCT) both worldwide and in Argentina is described. Projects in Russia, UK, Italy, Japan, Israel, and Argentina to develop AB-BNCT around different types of accelerators are briefly presented. In particular, the present status and recent progress of the Argentine project will be reviewed. The topics will cover: intense ion sources, accelerator tubes, transport of intense beams, beam diagnostics, the (9)Be(d,n) reaction as a possible neutron source, Beam Shaping Assemblies (BSA), a treatment room, and treatment planning in realistic cases.
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Terapia por Captura de Nêutron de Boro/instrumentação , Aceleradores de Partículas/instrumentação , Radiometria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Internacionalidade , Avaliação da Tecnologia BiomédicaRESUMO
OBJECTIVE: To identify the sociodemographic, socio-economic, clinical and behavioural factors that modify the experience of decayed, missing and filled teeth (DMFT) and caries prevalence in Nicaraguan children 9-12 years old. SUBJECTS AND METHODS: We conducted a cross-sectional study in 800 school children 9-12 years old in the city of León, Nicaragua. The clinical oral examinations to identify caries experience were undertaken by two trained and certified examiners. Sociodemographic, socio-economic and behavioural data were collected using questionnaires. Negative binomial regression (NBR) and binary logistic regression (BLR) models were used to model caries experience and caries prevalence, respectively. RESULTS: Mean DMFT index was 0.98 ± 1.74 and caries prevalence (DMFT > 0) was 37.9%. In the NBR model, the categories that increase the expected DMFT mean were: older age, female gender, presence of plaque, and if the school children received curative and curative/preventive dental care in the last year. In the BLR model, the odds of presenting with caries in the permanent dentition were increased in older children, those from large families, mothers with a positive dental attitude, and those school children who received curative and curative/preventive dental care in the last year. CONCLUSIONS: Using different models, we identified several sociodemographic, socio-economic, clinical and behavioural factors that modify the experience (NBR) and prevalence (BLR) of dental caries.
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PURPOSE: Encouraging Boron Neutron Capture Therapy (BNCT) clinical results obtained in recent years have stimulated intense research to develop accelerator-based neutron sources to be installed in clinical facilities. In this work an assessment of an accelerator-based BNCT facility for the treatment of different tumor targets was performed, comparing the accelerator-derived results with reported reactor-based trials under similar conditions and subjected to the same clinical protocols. MATERIALS AND METHODS: A set of real image studies was used to cover clinical-like cases of brain and head-and-neck tumors. In addition, two clinical cases of malignant nodular melanoma treated at the RA-6 BNCT facility in Argentina were used to thoroughly compare the clinical dosimetry with the accelerator-derived results. RESULTS: The minimum weighted dose delivered to the clinical target volume was higher than 30 Gy and 14 Gy for the brain tumor and head-and-neck cases, respectively, in agreement with those achieved in clinical applications. For the melanoma cases, the minimum tumor doses were equal or higher than those achieved with the RA-6 reactor for identical field orientation and protocol. The whole-body dose assessment showed that the maximum photon-equivalent doses for those normal organs close to the beam direction were below the upper limits considered in the protocols used in the present work. CONCLUSIONS: The obtained results indicate not only the good performance of the proposed beam shaping assembly design associated to the facility but also the potential applicability of accelerator-based BNCT in the treatment of both superficial and deep-seated tumors.
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Terapia por Captura de Nêutron de Boro/instrumentação , Neoplasias/radioterapia , Aceleradores de Partículas/instrumentação , Estudos de Viabilidade , Humanos , Neoplasias/patologia , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Carga Tumoral/efeitos da radiaçãoRESUMO
Within the frame of an ongoing project to develop a folded Tandem-Electrostatic-Quadrupole accelerator facility for Accelerator-Based Boron Neutron Capture Therapy (AB-BNCT) a theoretical study was performed to assess the treatment planning capability of different configurations of an optimized beam shaping assembly for such a facility. In particular this study aims at evaluating treatment plans for a clinical case of Glioblastoma.
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Terapia por Captura de Nêutron de Boro , Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Humanos , Método de Monte CarloRESUMO
There has been increasing interest in combining Boron Neutron Capture Therapy (BNCT) with standard radiotherapy, either concomitantly or as a BNCT treatment of a recurrent tumor that was previously irradiated with a medical electron linear accelerator (LINAC). In this work we report the simulated dosimetry of treatments combining X-rays and BNCT.
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Terapia por Captura de Nêutron de Boro , Radioterapia , Humanos , Método de Monte CarloRESUMO
Peutz-Jeghers syndrome is a autosomal dominant disorder characterized by hamartomatous polyposis of the gastrointestinal tract and mucocutaneous melanin pigmentation. This condition can occur and cause symptoms at any age, but intestinal obstruction due to intussusception is a frequent complication. Two cases of this syndrome associated to intussusception are reported. Both patients were girls, 2 and 8 years old respectively and underwent surgical treatment.