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1.
Medicine (Baltimore) ; 99(52): e23766, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33350761

RESUMO

OBJECTIVES: This study aimed to evaluate the diagnostic performance of magnetic resonance perfusion-weighted imaging (PWI) as a noninvasive method to assess post-treatment radiation effect and tumor progression in patients with glioma. METHODS: A systematic literature search was performed in the PubMed, Cochrane Library, and Embase databases up to March 2020. The quality of the included studies was assessed by the quality assessment of diagnostic accuracy studies 2. Data were extracted to calculate sensitivity, specificity, and diagnostic odds ratio (DOR), 95% Confidence interval (CI) and analyze the heterogeneity of the studies (Spearman correlation coefficient, I2 test). We performed meta-regression and subgroup analyses to identify the impact of study heterogeneity. RESULTS: Twenty studies were included, with available data for analysis on 939 patients and 968 lesions. All included studies used dynamic susceptibility contrast (DSC) PWI, four also used dynamic contrast-enhanced PWI, and three also used arterial spin marker imaging PWI. When DSC was considered, the pooled sensitivity and specificity were 0.83 (95% CI, 0.79 to 0.86) and 0.83 (95% CI, 0.78 to 0.87), respectively; pooled DOR, 21.31 (95% CI, 13.07 to 34.73); area under the curve (AUC), 0.887; Q∗, 0.8176. In studies using dynamic contrast-enhanced, the pooled sensitivity and specificity were 0.73 (95% CI, 0.66 to 0.80) and 0.80 (95% CI, 0.69 to 0.88), respectively; pooled DOR, 10.83 (95% CI, 2.01 to 58.43); AUC, 0.9416; Q∗, 0.8795. In studies using arterial spin labeling, the pooled sensitivity and specificity were 0.79 (95% CI, 0.69 to 0.87) and 0.78 (95% CI, 0.67 to 0.87), respectively; pooled DOR, 15.63 (95% CI, 4.61 to 53.02); AUC, 0.8786; Q∗, 0.809. CONCLUSIONS: Perfusion magnetic resonance imaging displays moderate overall accuracy in identifying post-treatment radiation effect and tumor progression in patients with glioma. Based on the current evidence, DSC-PWI is a relatively reliable option for assessing tumor progression after glioma radiotherapy.


Assuntos
Neoplasias Encefálicas , Glioma , Angiografia por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/radioterapia , Progressão da Doença , Glioma/diagnóstico , Glioma/radioterapia , Humanos , Estadiamento de Neoplasias , Efeitos da Radiação
2.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 39(5): 303-315, sept.-oct. 2020. graf
Artigo em Espanhol | IBECS | ID: ibc-198292

RESUMO

El modelo lineal sin umbral (MLSU) es una función dosis-respuesta teórica obtenida de extrapolar los efectos tardíos debidos a la exposición a altas dosis de radiación ionizante al rango de las bajas dosis, pero existen grandes incertidumbres respecto a su validez. La aceptación del MLSU como modelo probabilístico preponderante ha sobrevivido hasta nuestros días y constituye la piedra angular que sostiene las políticas actuales de protección radiológica. En las últimas décadas, los avances en biología molecular y evolutiva, en la inmunología del cáncer, así como los resultados obtenidos de los estudios epidemiológicos y en modelos animales, han puesto en entredicho la fiabilidad del MLSU en favor de otras alternativas, como la teoría hormética. A la vista de las evidencias, se hace necesario un debate entre las sociedades científicas implicadas y los organismos reguladores que aborde una redefinición de las bases de la protección radiológica, cuya importancia sería capital en el ámbito médico


The linear non-threshold model (LNTM) is a theoretical dose-response function as a result of extrapolating the late effects of high-dose exposure to ionizing radiation to the low-dose range, but there is great uncertainty about its validity. The acceptance of LNTM as the dominant probabilistic model have survived to the present day and it is actually the cornerstone of current radiation protection policies. In the last decades, advances in molecular and evolutive biology, cancer immunology, and many epidemiological and animal studies have cast serious doubts about the reliability of the NLTM, as well as suggesting alternative models, like the hormetic theory. Considering the given evidences, a discussion between the involved scientific societies and the regulatory commissions is promtly required in order to to reach a redefiniton of theradiation protection basis, as it would be specially crucial in the medical field


Assuntos
Humanos , Relação Dose-Resposta à Radiação , Hormese/efeitos da radiação , Radiobiologia/métodos , Carcinogênese/efeitos da radiação , Lesões por Radiação/prevenção & controle , 51569/prevenção & controle , Proteção Radiológica/normas , Doses de Radiação , Fracionamento da Dose de Radiação , Modelos Lineares , Medicina Nuclear/métodos , Radiação Ionizante/classificação , Efeitos Adversos de Longa Duração/prevenção & controle , Efeitos da Radiação , Radiometria/métodos
4.
J. nurs. health ; 10(2): 20102009, mai.2020.
Artigo em Português | LILACS, BDENF - Enfermagem | ID: biblio-1104137

RESUMO

Objetivo: analisar e categorizar o método de uso e benefícios e principais considerações sobre uso do laser em lesões induzidas por radiação. Método: revisão sistemática desenvolvidas em Public Medline, Literatura Latino-Americana do Caribe em Ciências da Saúde, Cumulative Index to Nursing and Allied Health Literature, SCOPUS e Biblioteca Virtual de Saúde. Resultados: analisou-se sete estudos. Observou-se em 86% (6) desses estudos uma conclusão positiva à terapêutica de laser de baixa intensidade, relatando: 43% (3) diminuição significativa e regressão da dor; 29% (2) redução significativa na duração e gravidade da mucosite e 29% (2) redução da inflamação e cicatrização. Conclusão: evidenciou-se melhora da cicatrização, da dor local e da capacidade anti-inflamatória. É necessário realizar mais pesquisas com amostras robustas que comparem os tipos de lasers, o comprimento das ondas e sua intensidade, para o seu uso como terapêutica.(AU)


Objective: to analyze and categorize the method of use and benefits and main considerations on the use of laser in radiation-induced injuries. Method: systematic review developed in the databases Public Medline, Latin American Caribbean Literature in Health Sciences, Cumulative Index to Nursing and Allied Health Literature, SCOPUS and Virtual Health Library. Results: seven studies were analyzed. A positive conclusion to low-level laser therapy was observed in 86% (6) of these studies, reporting: 43% (3) significant decrease and regression of pain; 29% (2) significant reduction in the duration and severity of mucositis and 29% (2) reduction in inflammation and healing. Conclusion: there was an improvement in healing, local pain and anti-inflammatory capacity. More research is needed with robust samples that compare the types of lasers, the length of the waves and their intensity, for their use as therapy.(AU)


Objetivo: analizar y clasificar el método de uso y los beneficios y las principales consideraciones sobre el uso del láser en lesiones inducidas por radiación. Método: revisión sistemática desarrollada en Public Medline, Literatura Latinoamericana del Caribe en Ciencias de la Salud, Índice acumulativo de literatura de enfermería y salud aliada, SCOPUS y Biblioteca Virtual en Salud. Resultados: se analizaron siete estudios. Se observó una conclusión positiva de la terapia con láser de bajo nivel en el 86% (6) de estos estudios: 43% (3) disminución significativa y regresión del dolor; 29% (2) reducción significativa en la duración y gravedad de la mucositis y 29% (2) reducción en la inflamación y la curación. Conclusión: hubo una mejora en la curación, dolor local y capacidad antiinflamatoria. Se necesita investigación con muestras robustas que comparen los tipos de láser, la longitud de las ondas y su intensidad, para su uso como terapia.(AU)


Assuntos
Efeitos da Radiação , Radiodermatite , Radioterapia , Terapia com Luz de Baixa Intensidade
5.
Sci Rep ; 10(1): 37, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913321

RESUMO

The exposure of germ cells to radiation introduces mutations in the genomes of offspring, and a previous whole-genome sequencing study indicated that the irradiation of mouse sperm induces insertions/deletions (indels) and multisite mutations (clustered single nucleotide variants and indels). However, the current knowledge on the mutation spectra is limited, and the effects of radiation exposure on germ cells at stages other than the sperm stage remain unknown. Here, we performed whole-genome sequencing experiments to investigate the exposure of spermatogonia and mature oocytes. We compared de novo mutations in a total of 24 F1 mice conceived before and after the irradiation of their parents. The results indicated that radiation exposure, 4 Gy of gamma rays, induced 9.6 indels and 2.5 multisite mutations in spermatogonia and 4.7 indels and 3.1 multisite mutations in mature oocytes in the autosomal regions of each F1 individual. Notably, we found two types of deletions, namely, small deletions (mainly 1~12 nucleotides) in non-repeat sequences, many of which showed microhomology at the breakpoint junction, and single-nucleotide deletions in mononucleotide repeat sequences. The results suggest that these deletions and multisite mutations could be a typical signature of mutations induced by parental irradiation in mammals.


Assuntos
Genoma , Mutação , Oócitos/fisiologia , Espermatogônias/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Raios gama , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Taxa de Mutação , Oócitos/efeitos da radiação , Efeitos da Radiação , Radiação Ionizante , Espermatogônias/efeitos da radiação , Sequenciamento Completo do Genoma
6.
Rev. esp. cir. oral maxilofac ; 41(2): 61-67, abr.-jun. 2019. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-191460

RESUMO

INTRODUCCIÓN: El colgajo peroneo es actualmente una de las técnicas más elegidas para la reconstrucción de defectos mandibulares. Muchos de los pacientes reconstruidos con este colgajo presentan patología oncológica que precisa tratamiento adyuvante con radioterapia. Los efectos adversos de la radioterapia sobre los tejidos son conocidos, pudiendo desembocar en osteoradionecrosis. El objetivo de este estudio es el análisis de la densidad ósea de los colgajos peroneos en los pacientes que han recibido radioterapia frente a los que no y su posible correlación con las complicaciones posteriores. MATERIAL Y MÉTODOS: Realizamos un estudio retrospectivo de los colgajos peroneos realizados por nuestro servicio desde enero 2011 hasta diciembre 2016. Los criterios de inclusión de los pacientes fue el haber sido reconstruidos con un colgajo peroneo y disponer de un TC de control a los tres meses postradioterapia en caso de haberla precisado. Se recogió la edad, densidad ósea peronea, desviación estándar cuerpo mandibular remanente y colgajo peroneo, así como las complicaciones postoperatorias. Los datos extraídos fueron analizados a través del Software SAS (Statistical Analisys System). RESULTADOS: En total se recogieron 61 pacientes, siendo la media de edad de 54,46 años. De estos 61 pacientes se excluyeron 11 al no presentar TC de control; de los 50 pacientes restantes, 27 recibieron tratamiento radioterápico adyuvante (54 %), mientras que 23 no la recibieron (46 %). En los pacientes irradiados, un alto porcentaje (84,62 %) recibieron altas dosis de radioterapia (> 60 Gy). Se encontraron diferencias estadísticamente significativas (p < 0,05) respecto a la edad y la desviación estándar de la densidad ósea del cuerpo mandibular remanente, mientras que en el resto de los parámetros no se encontraron diferencias estadísticamente significativas. Los pacientes irradiados presentaron un mayor porcentaje de complicaciones frente a los pacientes no irradiados, sin diferencias estadísticamente significativas. Discusión: Las nuevas técnicas de radioterapia de intensidad modulada permiten una dosis relativamente uniforme en un objetivo, evitando altas dosis en los tejidos circuncidantes. A pesar del avance en las técnicas de radioterapia, actualmente en la mayoría de centros se continúa realizando un tratamiento completo del volumen del lecho tumoral, que incluye en el campo de irradiación el colgajo con el que se reconstruye. Los casos de osteonecrosis mandibular que se presentaron fueron en pacientes irradiados y a nivel del cuerpo mandibular remanente. La densidad ósea a nivel del colgajo peroneo sí que presentó diferencias estadísticamente significativas en pacientes irradiados frente a no irradiados; este aspecto puede influir en el índice de complicaciones. CONCLUSIONES: Consideramos, con los resultados del estudio, plantear nuevos estudios prospectivos para valorar la necesidad de irradiar el tejido óseo del colgajo peroneo como parte del volumen del lecho tumoral, siendo que este tejido no ha estado en contacto con el tumor primario, ante el mayor índice de complicaciones asociados a la radioterapia en estos tejidos


INTRODUCTION: The fibular flap is currently one of the most chosen techniques for the reconstruction of mandibular defects. Many of the patients reconstructed with this flap present oncological pathology that requires adjuvant treatment with radiotherapy. The adverse effects of radiotherapy on tissues are known, and can lead to osteoradionecrosis. The aim of this study is to analyze the bone density of peroneal flaps in patients who have received radiotherapy against those who do not and their possible correlation with subsequent complications. MATERIAL AND METHODS: We designed a retrospective study of the fibular flaps performed by our service from January 2011 to December 2016. The criteria for inclusion of patients was to have been reconstructed with a peroneal flap and have a control CT at 3 months after radiotherapy. Age, bone density, standard deviation and further complications were extracted. The extracted data was analyzed through the SAS (statistical Analisys System) Software. RESULTS: 61 patients were collected; the mean age was of 54.46 years. Of these 61 patients were excluded 11 by not presenting control TC, of the 50 patients remaining, 27 received adjuvant radiotherapy treatment (54 %) while 23 did not receive (46 %). In irradiated patients a high percentage (84.62 %) received high doses of radiotherapy (> 60 Gy). Statistically significant differences were found (P < 0.05) with respect to age and standard deviation of bone density of the remaining mandibular body, while in the rest of the parameters no statistical significant differences were found. Irradiated patients presented a higher percentage of complications compared to non-irradiated patients without statistically significant differences. Discussion: The new techniques of intensity-modulated radiotherapy allow a relatively uniform dose in a target, avoiding high doses in the circumcising tissues. Despite the progress in radiotherapy techniques, currently in most centers, it continues to perform a complete treatment of the volume of the tumor bed that includes in the field of irradiation the flap with which it is reconstructed. The cases of mandibular osteonecrosis that were presented were in irradiated patients and in the remaining mandible. Bone density at the level of the fibular flap showed statistically significant differences in irradiated patients compared to non-irradiated, this aspect may influence in the index of complications. CONCLUSIONS: We consider to propose new prospective studies to assess the need to irradiate the bone tissue of the fibular flap as part of the volume of the tumor bed, knowing that this tissue has not been in contact with the primary tumor, and the high index of complications associated with radiotherapy


Assuntos
Humanos , Retalhos Cirúrgicos/imunologia , Fíbula/transplante , Reconstrução Mandibular/métodos , Neoplasias Mandibulares/radioterapia , Estudos Retrospectivos , Radioterapia/estatística & dados numéricos , Osteorradionecrose/epidemiologia , Resultado do Tratamento , Efeitos da Radiação
7.
BMC Genomics ; 20(1): 354, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072350

RESUMO

BACKGROUND: Evolution leaves an imprint in species through genetic change. At the molecular level, evolutionary changes can be explored by studying ratios of nucleotide substitutions. The interplay among molecular evolution, derived phenotypes, and ecological ranges can provide insights into adaptive radiations. Caecilians (order Gymnophiona), probably the least known of the major lineages of vertebrates, are limbless tropical amphibians, with adults of most species burrowing in soils (fossoriality). This enigmatic order of amphibians are very distinct phenotypically from other extant amphibians and likely from the ancestor of Lissamphibia, but little to nothing is known about the molecular changes underpinning their radiation. We hypothesised that colonization of various depths of tropical soils and of freshwater habitats presented new ecological opportunities to caecilians. RESULTS: A total of 8540 candidate groups of orthologous genes from transcriptomic data of five species of caecilian amphibians and the genome of the frog Xenopus tropicalis were analysed in order to investigate the genetic machinery behind caecilian diversification. We found a total of 168 protein-coding genes with signatures of positive selection at different evolutionary times during the radiation of caecilians. The majority of these genes were related to functional elements of the cell membrane and extracellular matrix with expression in several different tissues. The first colonization of the tropical soils was connected to the largest number of protein-coding genes under positive selection in our analysis. From the results of our study, we highlighted molecular changes in genes involved in perception, reduction-oxidation processes, and aging that likely were involved in the adaptation to different soil strata. CONCLUSIONS: The genes inferred to have been under positive selection provide valuable insights into caecilian evolution, potentially underpin adaptations of caecilians to their extreme environments, and contribute to a better understanding of fossorial adaptations and molecular evolution in vertebrates.


Assuntos
Proteínas de Anfíbios/genética , Anfíbios/genética , Evolução Molecular , Efeitos da Radiação , Seleção Genética , Proteínas de Anfíbios/efeitos da radiação , Anfíbios/classificação , Animais , Genoma , Anotação de Sequência Molecular , Fenótipo , Filogenia
8.
Rev. luna azul ; 49(0): 200-219, 2019. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-1121056

RESUMO

Introducción. Este trabajo de investigación se realizó en la Ciudad de Honda, Colombia. Identificó el efecto de la sombra de los árboles en la atenuación de la temperatura, humedad relativa, temperatura de superficie del suelo, radiación solar y ultravioleta (UV) y determinó requerimientos de agua para la vegetación arbórea. Metodología. Se tomaron datos de temperatura del aire y de superficie de suelo, humedad relativa del aire, radiaciones solares y UV bajo la sombra de árboles y a plena exposición. Resultados. Se encontró que la temperatura del aire osciló entre 50ºC a plena exposición solar y 41ºC bajo sombra. La temperatura de superficie presentó a plena exposición solar valores de 66.8ºC y 42.6ºC bajo sombra. La variación de la radiación solar registrada ofreció un valor de 17.13 mW/cm2 a plena exposición solar y 1.69 mW/cm2 bajo sombra. La radiación UV presentó valores de 8 a plena exposición solar y 5 bajo sombra. La demanda hídrica por planta/día varió entre 5 y más de 500 litros, siendo la demanda diaria cercana a 2500 m3 . Conclusiones. En la ciudad no se realiza riego a los árboles, lo que conduce a que se produzca un déficit hídrico evidenciado por la pérdida de follaje ocasionando mínimas atenuaciones a la radiación UV. Las especies más relevantes respecto a la sombra son almendro (Terminalia cattapa), Pallandé (Pitecellobium dulce), naranjuelo (Capparis odoratissima), guayacán carrapo (Bulnesia carrapo), chirlobirlo (Tecoma stands), cumulá (Aspidosperma polyneuron) y mango (Manguifera indica). Los árboles pueden generar un buen servicio ecosistémico por la sombra, este servicio está mediado por la selección de la especie y el manejo de que son objeto los árboles.


Introduction: This research work was carried out in the city of Honda, Colombia. It identified the effect of tree shade on temperature attenuation, relative humidity, soil surface temperature, solar and ultraviolet (UV) radiation, and determined water requirements for arboreal vegetation. Methodology: Data on air and soil surface temperature, relative air humidity, solar and UV radiation were taken under the shade of trees and at full exposure. Results: It was found that the air temperature ranged from 50ºC at full sun exposure to 41ºC under shade. The surface temperature was 66.8ºC and 42.6ºC under shade. The variation of the registered solar radiation offered a value of 17.13 mW/cm2 at full solar exposure and 1.69 mW/cm2 under shade. The UV radiation presented values of 8 at full solar exposure and 5 under shade. The water demand per plant/day varied between 5 and more than 500 liters, being the daily demand close to 2500 m3. Conclusions: There is no irrigation of trees in the city which leads to a water deficit evidenced by the loss of foliage causing minimal attenuations to UV radiation. The most relevant species regarding shade are almond (Terminalia cattapa), Pallandé (Pitecellobium dulce), orange (Capparis odoratissima), guayacán carrapo (Bulnesia carrapo), chirlobirlo (Tecoma stands), cumula (Aspidosperma polyneuron) and mango (Manguifera indica). Trees can generate a good ecosystem service by shade which is mediated by the selection of the species and the management of the trees.


Assuntos
Humanos , Cidades , Efeitos da Radiação , Área Urbana , Ecologia
9.
Rev. méd. panacea ; 7(3): 97-100, sept.-dic. 2018.
Artigo em Espanhol | LILACS | ID: biblio-1016897

RESUMO

Objetivo: Identificar la producción científica sobre nivel de conocimientos, actitudes y prácticas sobre fotoprotección en padres de menores de 14 años latinoamericanos. Materiales y métodos:Estudio bibliométrico descriptivo y transversal. Se realizó una búsqueda bibliográfica en las bases de datos: PubMed, Scopus y la Biblioteca Virtual de Salud, utilizando las palabras claves: "fotoprotección" "niños", "escolares", entre el primero de enero del 2013 al 31 de junio del 2018. Se excluyeron artículos no originales o que no midieran conocimiento sobre fotoprotección. Resultado: Se encontró un total de seis artículos el 28.3% de los padres reportaron que sus hijos se exponen más de 60 minutos al sol entre semana; en el fin de semana se incrementa a un 42.8%. En Chile, el 14.2% de los niños han presentado alguna vez quemadura solar, con 2/3 de la población de estudio pasan más de 2 horas diarias al exterior. En Uruguay, El 55% de los padres afirmó que se protegen del sol, el 30% solo a veces y el 15% no se protege. En Cuba el 72.5% han presentado al menos una quemadura solar. En Perú, El estudio peruano demostró que el 48% utiliza protector solar en crema, el 46% ropa de protección y el 51% gorro o sombrero. Conclusiones: Se requieren intervenciones sanitarias para incrementar el conocimiento de los padres sobre fotoprotección, en México demuestra que una intervención educativa puede incrementar en un futuro el conocimiento de los jóvenes en el cuidado de la piel. (AU)


Objective: To identify scientific production on the level of knowledge, attitudes, and practices on photoprotection in parents of children under 14 years of age in Latin America. Materials and methods: Descriptive and transversal bibliometric study. A bibliographic search was carried out in the databases: PubMed, Scopus and the Virtual Health Library, using the keywords: "photoprotection" "children", "school children", between January 1, 2013, and June 31, 2018, We excluded articles that were not original or that did not measure knowledge about photoprotection. Result: A total of six articles were found, 28.3% of parents reported that their children are exposed to more than 60 minutes in the sun during the week; in the weekend it increases to 42.8%. In Chile, 14.2% of children have ever presented sunburn, with 2/3 of the study population spending more than 2 hours a day abroad. In Uruguay, 55% of parents said they protect themselves from the sun, 30% only sometimes and 15% do not protect themselves. In Cuba, 72.5% have presented at least one sunburn. In Peru, the Peruvian study showed that 48% use sunscreen cream, 46% protective clothing and 51% hat or hat. Conclusions: Health interventions are required to increase parents' knowledge about photoprotection, in Mexico it shows that an educational intervention can increase the knowledge of young people in skin care in the future. (AU)


Assuntos
Humanos , Masculino , Feminino , Efeitos da Radiação , Conhecimentos, Atitudes e Prática em Saúde , Banho de Sol , Creme para a Pele , Epidemiologia Descritiva , Estudos Transversais
10.
J Med Econ ; 21(6): 622-628, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29571273

RESUMO

AIMS: To estimate incremental healthcare resource utilization (HRU) and costs associated with skeletal-related events (SREs) secondary to multiple myeloma (MM), and HRU and cost differences in patients with one vs multiple SREs. METHODS: Adults with MM diagnosis between January 1, 2010-December 31, 2014, with benefits coverage ≥12 months pre- and ≥6 months post-diagnosis were followed to last coverage date or December 31, 2015, excluding patients with prior anti-myeloma treatment or cancers. SREs were identified by diagnosis or procedure codes (pathological fracture, spinal cord compression, radiation, or surgery to the bone). SRE patients (index = first post-diagnosis SRE) were propensity score matched 1:1 to patients without SRE (assigned pseudo-index) using baseline characteristics, and ≥1 month of continuous enrollment after index/pseudo-index date was required. Per-patient-per year (PPPY) HRU and costs (2016 US$) were determined for inpatient, outpatient, emergency department (ED), and outpatient pharmacy services during follow-up. Wilcoxon signed rank for means and McNemar's tests for proportions were used to assess differences. Negative binomial regression and generalized linear regression analyses estimated differences in HRU and costs, respectively, for the comparison of single vs multiple SREs. RESULTS: Each cohort included 848 patients (mean age = 61 - 62 years, 57% male) with no significant differences in pre-index demographic or clinical characteristics between matched cohorts. Versus non-SRE patients, SRE patients had significantly higher PPPY use (p < .0001) of inpatient hospitalizations, ED visits, outpatient pharmacy, and higher direct medical costs ($188,723 vs $108,160, p < .0001). Adjusted PPPY total costs were $209,820 in patients with multiple SREs; $159,797 in patients with one SRE. LIMITATIONS: SRE misclassification and residual confounding are possible. CONCLUSIONS: Among patients with MM, average annual costs were substantially higher in patients with SRE compared with matched non-SRE patients. The economic burden of SRE increased further with multiple events.


Assuntos
Doenças Ósseas/economia , Doenças Ósseas/etiologia , Mieloma Múltiplo/complicações , Adulto , Idoso , Comorbidade , Feminino , Fraturas Ósseas/economia , Gastos em Saúde , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Serviços de Saúde/economia , Serviços de Saúde/estatística & dados numéricos , Humanos , Revisão da Utilização de Seguros , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Pontuação de Propensão , Efeitos da Radiação , Estudos Retrospectivos , Compressão da Medula Espinal/economia , Estados Unidos
11.
Astrobiology ; 18(2): 133-189, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29431479

RESUMO

Proxima Centauri b provides an unprecedented opportunity to understand the evolution and nature of terrestrial planets orbiting M dwarfs. Although Proxima Cen b orbits within its star's habitable zone, multiple plausible evolutionary paths could have generated different environments that may or may not be habitable. Here, we use 1-D coupled climate-photochemical models to generate self-consistent atmospheres for several evolutionary scenarios, including high-O2, high-CO2, and more Earth-like atmospheres, with both oxic and anoxic compositions. We show that these modeled environments can be habitable or uninhabitable at Proxima Cen b's position in the habitable zone. We use radiative transfer models to generate synthetic spectra and thermal phase curves for these simulated environments, and use instrument models to explore our ability to discriminate between possible planetary states. These results are applicable not only to Proxima Cen b but to other terrestrial planets orbiting M dwarfs. Thermal phase curves may provide the first constraint on the existence of an atmosphere. We find that James Webb Space Telescope (JWST) observations longward of 10 µm could characterize atmospheric heat transport and molecular composition. Detection of ocean glint is unlikely with JWST but may be within the reach of larger-aperture telescopes. Direct imaging spectra may detect O4 absorption, which is diagnostic of massive water loss and O2 retention, rather than a photosynthetic biosphere. Similarly, strong CO2 and CO bands at wavelengths shortward of 2.5 µm would indicate a CO2-dominated atmosphere. If the planet is habitable and volatile-rich, direct imaging will be the best means of detecting habitability. Earth-like planets with microbial biospheres may be identified by the presence of CH4-which has a longer atmospheric lifetime under Proxima Centauri's incident UV-and either photosynthetically produced O2 or a hydrocarbon haze layer. Key Words: Planetary habitability and biosignatures-Planetary atmospheres-Exoplanets-Spectroscopic biosignatures-Planetary science-Proxima Centauri b. Astrobiology 18, 133-189.


Assuntos
Evolução Biológica , Exobiologia/métodos , Meio Ambiente Extraterreno , Modelos Biológicos , Planetas , Atmosfera/química , Dióxido de Carbono/química , Monóxido de Carbono/química , Clima , Evolução Planetária , Exobiologia/instrumentação , Temperatura Alta , Oceanos e Mares , Efeitos da Radiação , Telescópios , Água/química
12.
Radiol Med ; 123(3): 185-190, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29086381

RESUMO

PURPOSE: To determine the frequency of unindicated CT phases and the resultant excess of absorbed radiation doses to the uterus and ovaries in women of reproductive age who have undergone CT for non-traumatic abdomino-pelvic emergencies. MATERIALS AND METHODS: We reviewed all abdomino-pelvic CT examinations in women of reproductive age (40 years or less), between 1 June 2012 and 31 January 2015. We evaluated the appropriateness of each CT phase on the basis of clinical indications, according to ACR appropriateness criteria and evidence-based data from the literature. The doses to uterus and ovaries for each phase were calculated with the CTEXPO software, taking into consideration the size-specific dose estimate (SSDE) after measuring the size of every single patient. RESULTS: The final cohort was composed of 76 female patients with an average age of 30 (from 19 to 40 years). In total, 197 CT phases were performed with an average of 2.6 phases per patient. Out of these, 93 (47%) were unindicated with an average of 1.2 inappropriate phases per patient. Unindicated scans were most frequent for appendicitis and unlocalized abdominal pain. The excesses of mean radiation doses to the uterus and ovaries due to unindicated phases were, respectively, of 38 and 33 mSv per patient. CONCLUSION: In our experience, unindicated additional CT phases were numerous with a significant excess radiation dose without an associated clinical benefit. This excess of radiation could have been avoided by widespread adoption of the ACR appropriateness criteria and evidence-based data from the literature.


Assuntos
Abdome/diagnóstico por imagem , Dor Abdominal/diagnóstico por imagem , Apendicite/diagnóstico por imagem , Emergências , Pelve/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Procedimentos Desnecessários , Adulto , Medicina Baseada em Evidências , Feminino , Humanos , Valor Preditivo dos Testes , Doses de Radiação , Efeitos da Radiação , Radiografia Abdominal , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Procedimentos Desnecessários/efeitos adversos
14.
Environ Health Prev Med ; 22(1): 73, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29165177

RESUMO

BACKGROUND: This study aimed to examine the level of perception of the technical terms related to the effect of radiation on the human body among residents of the six prefectures of Miyagi, Fukushima, Tokyo, Aichi, Hiroshima, and Nagasaki in Japan. Miyagi and Fukushima were selected as devastated area by Great East Japan Earthquake. Tokyo and Aichi were selected as control. Hiroshima and Nagasaki were selected as the A-bombed area. METHODS: A total of 1030 respondents, 172, 173, 171, 173, 171, and 170, respectively, were surveyed. Differences in the recognition level of technical terms related to the effect of radiation on the human body among residents of the six prefectures were assessed. RESULTS: The highest recognition levels were reported by the respondents from Fukushima (17 items). Those from Miyagi scored the second highest recognition levels (10 out of the 17 terms); the second highest recognition levels for the remaining seven terms were marked by the respondents of Tokyo. Respondents in the Tohoku region had a better recognition for the technical terminology relevant to the effect of radiation on the human body. CONCLUSIONS: Our findings indicate a need for continued, comprehensive risk communication pertaining to health hazards of radiation exposure in Tohoku region. Concerted efforts by central/local governments and other stakeholders are required to allay the anxiety/stress related to radiation exposure among the residents.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Efeitos da Radiação , Exposição à Radiação , Humanos , Japão , Exposição à Radiação/efeitos adversos , Terminologia como Assunto
15.
J Radiol Prot ; 37(3): R19-R42, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28703713

RESUMO

This paper presents an overview of the nuclear accident that occurred at the Mayak Production Association (PA) in the Russian Federation on 29 September 1957, often referred to as 'Kyshtym Accident', when 20 MCi (740 PBq) of radionuclides were released by a chemical explosion in a radioactive waste storage tank. 2 MCi (74 PBq) spread beyond the Mayak PA site to form the East Urals Radioactive Trace (EURT). The paper describes the accident and gives brief characteristics of the efficacy of the implemented protective measures that made it possible to considerably reduce doses to the exposed population. The paper also provides retrospective dosimetry estimates for the members of the EURT Cohort (EURTC) which comprises approximately 21 400 people. During the first two years after the accident a decrease in the group average leukocyte (mainly due to neutrophils and lymphocytes) and thrombocyte count was observed in the population. At later dates an increased excess relative risk of solid cancer incidence and mortality was found in the EURTC.


Assuntos
Explosões/história , Neoplasias Induzidas por Radiação/história , Efeitos da Radiação , Proteção Radiológica/história , Liberação Nociva de Radioativos/história , Feminino , História do Século XX , Humanos , Masculino , Neoplasias Induzidas por Radiação/epidemiologia , Radiometria/história , Federação Russa/epidemiologia
17.
São Paulo; s.n; s. n; 2017. 1-94 p. tab, graf.
Tese em Português | LILACS | ID: biblio-833866

RESUMO

Diversos produtos tópicos são desenvolvidos a fim de se evitar os efeitos nocivos da radiação ultravioleta (UV), dentre eles, os protetores solares constituídos por filtros físicos e/ou químicos. No entanto, os filtros químicos podem promover eventos adversos, razão pela qual a busca de ativos em fontes naturais tem-se mostrado de grande importância. A microalga Botryococcus braunii pode ser de potencial interesse em aplicações cosméticas, pois foi descrito que seu extrato aquoso apresentou redução da desidratação cutânea, induziu a produção do colágeno, bem como promoveu atividade antioxidante. Assim, o estudo visou analisar o auxilio da B. braunii na fotoproteção cutânea e na proteção da pele por meio da ação antioxidante in vitro. As formulações, constituídas de biomassa da microalga ou de seus extratos, acrescidas ou não de filtros, foram avaliadas quanto à: ação antioxidante, atividade fotoprotetora in vitro e fotoestabilidade. A B. braunii apresentou bom desempenho de crescimento, contendo lipídeos (25,65%) e proteínas (49,17%) em proporção semelhante à descrita na literatura. A presença de fenóis totais e a ação antioxidante foram analisadas nos extratos obtidos com clorofórmio, metanol e etanol 70%. O extrato obtido com etanol 70% foi o que apresentou maior concentração de fenóis totais (68,9 µg/mL de ácido cafeico), porém inferior ao relatado na literatura; e a ação antioxidante não foi considerada significativa ao se comparar com o padrão Trolox®. Nas formulações, os extratos foram considerados ineficientes para ação antioxidante. Quanto à atividade fotoprotetora in vitro e fotoestabilidade, a B. braunii não apresentou eficácia adequada, existindo, porém, a possibilidade de os extratos atuarem na região da luz visível e contribuírem contra os efeitos danosos provocados por esta radiação à pele


Several topical products are developed in order to avoid the harmful effects of ultraviolet (UV) radiation, including sunscreens made by physical and/or chemical filters. However, chemical filters may promote adverse events, which is why the search for actives from natural sources has proven to be of great importance. The microalgae Botryococcus braunii may be of potential interest in cosmetic applications, because it has been reported that its aqueous extract showed a reduction in skin dehydration, induced collagen production and promoted antioxidant activity. Thus, the study aimed to analyze the contribution of B. braunii in skin photoprotection and skin protection through in vitro antioxidant action. The formulations, consisting of biomass from the microalgae or their extracts, supplemented or not by filters, were evaluated for: antioxidant activity, photoprotective activity in vitro and photostability. The B. braunii showed good growth performance, containing lipids (25.65%) and protein (49.17%) in similar proportion to the described by the literature. The presence of phenolic compounds and antioxidant activity were analyzed in extracts obtained with chloroform, methanol and 70% ethanol. The extract obtained with 70% ethanol showed the highest concentration of total phenolics (68.9 mg/mL caffeic acid), but lower than that reported in the literature; and the antioxidant action was not considered significant when compared to the Trolox® standard. In the formulations, the extracts were considered inefficient for antioxidant action. In relation to the in vitro photoprotection activity and photostability, B. braunii did not provide adequate efficacy, however, there is a possibility that the extracts have an ability to act in the visible light region and contribute to the protection from the harmful effects caused by that radiation to the skin


Assuntos
Cosméticos/farmacologia , Microalgas/classificação , Efeitos da Radiação , Antioxidantes/farmacologia , Raios Ultravioleta
18.
Appl Physiol Nutr Metab ; 41(12): 1248-1254, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27863208

RESUMO

The cucurbits (prebiotics) were investigated as novel agents for radio-modification against gastrointestinal injury. The cell-cycle fractions and DNA damage were monitored in HCT-15 cells. A cucurbit extract was added to culture medium 2 h before irradiation (6 Gy) and was substituted by fresh medium at 4 h post-irradiation. The whole extract of the fruits of Lagenaria siceraria, Luffa cylindrica, or Cucurbita pepo extract enhanced G2 fractions (42%, 34%, and 37%, respectively) as compared with control (20%) and irradiated control (31%). With cucurbits, the comet tail length remained shorter (L. siceraria, 28 µm; L. cylindrica, 34.2 µm; C. pepo, 36.75 µm) than irradiated control (41.75 µm). For in vivo studies, L. siceraria extract (2 mg/kg body weight) was administered orally to mice at 2 h before and 4 and 24 h after whole-body irradiation (10 Gy). L. siceraria treatment restored the glutathione contents to 48.8 µmol/gm as compared with control (27.6 µmol/gm) and irradiated control (19.6 µmol/gm). Irradiation reduced the villi height from 379 to 350 µm and width from 54 to 27 µm. L. siceraria administration countered the radiation effects (length, 366 µm; width, 30 µm, respectively) and improved the villi morphology and tight junction integrity. This study reveals the therapeutic potential of cucurbits against radiation-induced gastrointestinal injury.


Assuntos
Frutas/química , Gastroenteropatias/prevenção & controle , Lagenidium/química , Extratos Vegetais/uso terapêutico , Prebióticos , Lesões Experimentais por Radiação/prevenção & controle , Protetores contra Radiação/uso terapêutico , Animais , Linhagem Celular Tumoral , Cucurbita/química , Dano ao DNA , Frutas/economia , Fase G2/efeitos da radiação , Gastroenteropatias/dietoterapia , Gastroenteropatias/metabolismo , Gastroenteropatias/patologia , Glutationa/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos da radiação , Mucosa Intestinal/ultraestrutura , Luffa/química , Masculino , Camundongos , Microvilosidades/metabolismo , Microvilosidades/patologia , Microvilosidades/efeitos da radiação , Microvilosidades/ultraestrutura , Extratos Vegetais/metabolismo , Efeitos da Radiação , Lesões Experimentais por Radiação/dietoterapia , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Protetores contra Radiação/metabolismo , Distribuição Aleatória , Análise de Sobrevida , Junções Íntimas/metabolismo , Junções Íntimas/patologia , Junções Íntimas/efeitos da radiação , Junções Íntimas/ultraestrutura
19.
J Neuroinflammation ; 13(1): 215, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27576527

RESUMO

BACKGROUND: Primary central nervous system (CNS) neoplasms and brain metastases are routinely treated with whole-brain radiation. Long-term survival occurs in many patients, but their quality of life is severely affected by the development of cognitive deficits, and there is no treatment to prevent these adverse effects. Neuroinflammation, associated with activation of brain-resident microglia and infiltrating monocytes, plays a pivotal role in loss of neurological function and has been shown to be associated with acute and long-term effects of brain irradiation. Colony-stimulating factor 1 receptor (CSF-1R) signaling is essential for the survival and differentiation of microglia and monocytes. Here, we tested the effects of CSF-1R blockade by PLX5622 on cognitive function in mice treated with three fractions of 3.3 Gy whole-brain irradiation. METHODS: Young adult C57BL/6J mice were given three fractions of 3.3 Gy whole-brain irradiation while they were on diet supplemented with PLX5622, and the effects on periphery monocyte accumulation, microglia numbers, and neuronal functions were assessed. RESULTS: The mice developed hippocampal-dependent cognitive deficits at 1 and 3 months after they received fractionated whole-brain irradiation. The impaired cognitive function correlated with increased number of periphery monocyte accumulation in the CNS and decreased dendritic spine density in hippocampal granule neurons. PLX5622 treatment caused temporary reduction of microglia numbers, inhibited monocyte accumulation in the brain, and prevented radiation-induced cognitive deficits. CONCLUSIONS: Blockade of CSF-1R by PLX5622 prevents fractionated whole-brain irradiation-induced memory deficits. Therapeutic targeting of CSF-1R may provide a new avenue for protection from radiation-induced memory deficits.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/efeitos da radiação , Transtornos da Memória/metabolismo , Transtornos da Memória/prevenção & controle , Receptor de Fator Estimulador de Colônias de Macrófagos/antagonistas & inibidores , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Aminopiridinas/farmacologia , Aminopiridinas/uso terapêutico , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pirróis/farmacologia , Pirróis/uso terapêutico , Efeitos da Radiação
20.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 72(5): 424-9, 2016 May.
Artigo em Japonês | MEDLINE | ID: mdl-27211088

RESUMO

Recently, radiation damage to the detector apparatus employed in computed radiography (CR) mammography has become problematic. The CR system and the imaging plate (IP) applied to quality control (QC) program were also used in clinical mammography in our hospital, and the IP to which radiation damage has occurred was used for approximately 5 years (approximately 13,000 exposures). We considered using previously acquired QC image data, which is stored in a server, to investigate the influence of radiation damage to an IP. The mammography unit employed in this study was a phase contrast mammography (PCM) Mermaid (KONICA MINOLTA) system. The QC image was made newly, and it was output in the film, and thereafter the optical density of the step-phantom image was measured. An input (digital value)-output (optical density) conversion curve was plotted using the obtained data. The digital values were then converted to optical density values using a reference optical density vs. digital value curve. When a high radiation dose was applied directly, radiation damage occurred at a position on the IP where no object was present. Daily QC for mammography is conducted using an American College of Radiology (ACR) accreditation phantom and acrylic disc, and an environmental background density measurement is performed as one of the management indexes. In this study, the radiation damage sustained by the acrylic disc was shown to differ from that of the background. Thus, it was revealed that QC results are influenced by radiation damage.


Assuntos
Mamografia/métodos , Efeitos da Radiação , Tomografia Computadorizada por Raios X/métodos , Mamografia/instrumentação , Controle de Qualidade , Doses de Radiação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/instrumentação
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