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1.
Sci Rep ; 14(1): 2084, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267488

RESUMO

We present an experimental study of plasmonic slanted slit gratings (PSSGs) designed to achieve directional coupling between an incident light beam and surface plasmon polaritons (SPPs) propagating along the surface of the structure. We also investigate mirrored PSSG pairs interconnected by a plasmonic slab waveguide. The structures are fabricated using direct milling by a gallium focused ion beam (FIB). In a mirrored pair arrangement, the first PSSG couples a perpendicularly-incident light beam to SPPs propagating in one direction along the waveguide, while the second PSSG decouples SPPs to perpendicularly-emerging light. This configuration shows promise for sensing applications due to the high sensitivity of the excited SPPs to changes in the refractive index of the bounding medium, and the separation of the optics from the fluidics by the substrate. The design also exhibits robustness to fabrication tolerances. The optical characteristics and sensing potential are investigated theoretically and experimentally, highlighting its potential for a wide range of applications.

2.
Rev Chil Pediatr ; 89(5): 638-643, 2018 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-30571807

RESUMO

INTRODUCTION: Cystic fibrosis (CF) is an inherited, progressive, multisystem disease. Better physical capacity may slow disease progression, thus improving prognosis and survival. The objective of this research was to evaluate the physical capacity of children admitted to the National CF Pro gram of the Metropolitan Region, Chile. PATIENTS AND METHOD: A multicenter, cross-sectional stu dy design was used. The inclusion criteria were children aged 6 to 12 years enrolled in the National CF Program; Tanner sexual maturity stage I, no respiratory exacerbations in the last 30 days, and no musculoskeletal pathologies. The maximum aerobic capacity was assessed through the peak oxygen uptake (VO2peak) and determined with an incremental protocol in a magnetic cycle ergometer connected to an ergo-spirometer with which, at the same time, respiratory gases, oxygen consumption and carbon dioxide production values every 30 seconds, anaerobic threshold, and maximum workload were analyzed. The values of forced vital capacity (FVC), forced expiratory volume in 1 second (FEVJ, FEVj/FVC ratio, and forced expiratory flows between 25% and 75% of vital capacity were assessed through ergo-spirometry. At the beginning of the ergo-spirometry, arterial oxygen saturation, respiratory rate, heart rate, blood pressure, tidal volume and the per ception of lower extremity fatigue and dyspnea were recorded using the modified Borg scale. The test lasted approximately 10 minutes. RESULTS: The clinical records of 43 children collected from six health centers were reviewed. Out of these, 29 children met inclusion criteria, and 23 were re cruited. Two children were unable to participate, reducing the final subject group to 21 (13 males, 8 females). The mean age was 8.8 ± 2 years; weight 30.5 ± 10.9 kg; height 1.32 ± 0.11 m; and body mass index 17.1 ± 3.5 (z-score 0.01 ± 1.34). More than half of the children (61%) had normal weight. The obtained VO2peak was 43.7 ± 6.5 ml/min/kg (106.7 ± 19.8% of the predictive values). Only 10% of the children had values lower than those predicted by sex and age. No correlations were found between VO2peak and anthropometric and pulmonary function variables. Conclu sion: Most of the evaluated children (90%) had physical capacity similar to healthy subjects by sex and age.


Assuntos
Fibrose Cística/fisiopatologia , Aptidão Física/fisiologia , Criança , Chile , Estudos Transversais , Teste de Esforço , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Consumo de Oxigênio , Espirometria , Capacidade Vital
3.
Rev. chil. pediatr ; 89(5): 638-643, oct. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-978136

RESUMO

Resumen: Introducción: La fibrosis quística (FQ) es una enfermedad multisistémica hereditaria y progresiva. Una mejor capacidad física puede retardar la progresión de la enfermedad, mejorando así el pronós tico y la supervivencia. El objetivo de esta investigación fue evaluar la capacidad física de los niños admitidos en el programa nacional de FQ de la Región Metropolitana, Chile. Pacientes y Método: Se utilizó un diseño de estudio transversal multicéntrico. Los criterios de inclusión fueron: niños de 6 a 12 años de edad, incluidos en el Programa Nacional de FQ, madurez sexual Tanner I, ausencia de exacerbaciones respiratorias en los últimos 30 días y ausencia de enfermedades musculoesqueléticas. La capacidad aeróbica máxima fue evaluada a través del consumo pico de oxígeno (VO2pico) y se determinó con un protocolo incremental en un cicloergómetro magnético conectado a un ergoespirómetro en el que paralelamente se analizaron los gases respiratorios: valores de consumo de oxí geno y producción de dióxido de carbono cada 30 segundos, umbral anaeróbico y carga máxima de trabajo. Además, se evaluaron los valores de capacidad vital forzada (CVF), volumen espiratorio al primer segundo (VEFj), relación VEFj/CVF y los flujos espiratorios forzados entre el 25 y 75% de la capacidad vital. Durante la prueba se registró: saturación arterial de oxígeno, frecuencia respiratoria, frecuencia cardíaca, presión arterial, volumen corriente y se consultó la percepción de fatiga de extre midades inferiores y disnea a través de la escala de Borg modificada. La duración aproximada del test fue alrededor de 10 minutos. Resultados: Se revisaron los registros clínicos de 43 niños, recogidos en seis centros de salud. Veintinueve niños cumplieron los criterios de inclusión siendo 23 reclutados. Dos niños no pudieron participar, reduciendo el grupo final de sujetos a 21 (13:8 varones:mujeres). La edad media fue de 8,8 ± 2 años; el peso fue de 30,5 ± 10,9 kg; la talla fue de 1,32 ± 0,11 m y el índice de masa corporal fue de 17,1 ± 3,5 (z-score 0,01 ± 1,34). Más de la mitad (61%) de los niños estaba eutrófico. El VO2pico obtenido fue de 43,7 ± 6,5 ml/min/kg (106,7 ± 19,8% de los valores teóricos de referencia). Sólo el 10% de los niños tenían valores inferiores a los valores teóricos esperados para población normal, ajustados por sexo y edad. No se encontraron correlaciones entre el VO2pico y las variables antropométricas y de función pulmonar. Conclusión: La mayoría de los niños evaluados (90%) tenían capacidad física similar a los valores teóricos de referencia para niños sanos ajustados por sexo y edad.


Abstract: Introduction: Cystic fibrosis (CF) is an inherited, progressive, multisystem disease. Better physical capacity may slow disease progression, thus improving prognosis and survival. The objective of this research was to evaluate the physical capacity of children admitted to the National CF Pro gram of the Metropolitan Region, Chile. Patients and Method: A multicenter, cross-sectional stu dy design was used. The inclusion criteria were children aged 6 to 12 years enrolled in the National CF Program; Tanner sexual maturity stage I, no respiratory exacerbations in the last 30 days, and no musculoskeletal pathologies. The maximum aerobic capacity was assessed through the peak oxygen uptake (VO2peak) and determined with an incremental protocol in a magnetic cycle ergometer connected to an ergo-spirometer with which, at the same time, respiratory gases, oxygen consumption and carbon dioxide production values every 30 seconds, anaerobic threshold, and maximum workload were analyzed. The values of forced vital capacity (FVC), forced expiratory volume in 1 second (FEVj), FEVj/FVC ratio, and forced expiratory flows between 25% and 75% of vital capacity were assessed through ergo-spirometry. At the beginning of the ergo-spirometry, arterial oxygen saturation, respiratory rate, heart rate, blood pressure, tidal volume and the per ception of lower extremity fatigue and dyspnea were recorded using the modified Borg scale. The test lasted approximately 10 minutes. Results: The clinical records of 43 children collected from six health centers were reviewed. Out of these, 29 children met inclusion criteria, and 23 were re cruited. Two children were unable to participate, reducing the final subject group to 21 (13 males, 8 females). The mean age was 8.8 ± 2 years; weight 30.5 ± 10.9 kg; height 1.32 ± 0.11 m; and body mass index 17.1 ± 3.5 (z-score 0.01 ± 1.34). More than half of the children (61%) had normal weight. The obtained VO2peak was 43.7 ± 6.5 ml/min/kg (106.7 ± 19.8% of the predictive values). Only 10% of the children had values lower than those predicted by sex and age. No correlations were found between VO2peak and anthropometric and pulmonary function variables. Conclu sion: Most of the evaluated children (90%) had physical capacity similar to healthy subjects by sex and age.


Assuntos
Humanos , Masculino , Feminino , Criança , Aptidão Física/fisiologia , Fibrose Cística/fisiopatologia , Consumo de Oxigênio , Espirometria , Chile , Capacidade Vital , Volume Expiratório Forçado , Estudos Transversais , Teste de Esforço
4.
Nutr Hosp ; 35(4): 789-795, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-30070865

RESUMO

BACKGROUND: cystic fibrosis (CF) is the most common inherited disease in Caucasian population. Nowadays, long survival has led to the emergence of new complications, such as CF bone disease (CFBD), which is characterized by increased fracture risk. OBJECTIVES: evaluate the association of bone mineral density (BMD) with lung function and BMD with 25-hydroxivitamin D (25OHD) plasmatic levels in children/adolescents with CF. METHODS: we conducted a multicenter, cross-sectional study with clinically stable CF patients between five and 18 years. Weight, height, pubertal development, BMD and body composition (DXA), pulmonary function (FEV1 and FEF25-75) and 25OHD plasmatic levels were measured. Patients answered food intake and physical activity surveys. p values under 0.05 were considered as statistically significant. RESULTS: thirty-seven patients were enrolled, 51% with normal respiratory function. Mean BMD Z-score in lumbar spine and in total body less head were -0.4 and -0.5 respectively. Twenty seven percent had a fat free mass index below the third percentile, 89% had 25OHD levels lower than 30 ng/ml and 78.4% had a low calcium intake. We did not find any correlations between BMD Z-scores, lung function or 25OHD levels. Patients with fat free mass (FFM) below the third percentile had BMD Z-score lower than -1 more frequently, in both locations (p < 0.006 and p < 0.001, respectively). CONCLUSIONS: although most assessed patients had normal BMD and normal lung function, a high proportion had low: FFM, calcium intake and 25OHD levels. The association between low FFM and low BMD highlights the importance of improving body composition in CF patients, in order to prevent future CFBD.


Assuntos
Composição Corporal , Densidade Óssea , Fibrose Cística/metabolismo , Testes de Função Respiratória , Vitamina D/metabolismo , Adolescente , Criança , Chile/epidemiologia , Estudos Transversais , Fibrose Cística/sangue , Fibrose Cística/fisiopatologia , Feminino , Humanos , Hidroxicolecalciferóis/sangue , Masculino , Estado Nutricional
5.
Nutr. hosp ; 35(4): 789-795, jul.-ago. 2018. graf, tab
Artigo em Inglês | IBECS | ID: ibc-179869

RESUMO

Background: cystic fibrosis (CF) is the most common inherited disease in Caucasian population. Nowadays, long survival has led to the emergence of new complications, such as CF bone disease (CFBD), which is characterized by increased fracture risk. Objectives: evaluate the association of bone mineral density (BMD) with lung function and BMD with 25-hydroxivitamin D (25OHD) plasmatic levels in children/adolescents with CF. Methods: we conducted a multicenter, cross-sectional study with clinically stable CF patients between five and 18 years. Weight, height, pubertal development, BMD and body composition (DXA), pulmonary function (FEV1 and FEF25-75) and 25OHD plasmatic levels were measured. Patients answered food intake and physical activity surveys. p values under 0.05 were considered as statistically significant. Results: thirty-seven patients were enrolled, 51% with normal respiratory function. Mean BMD Z-score in lumbar spine and in total body less head were -0.4 and -0.5 respectively. Twenty seven percent had a fat free mass index below the third percentile, 89% had 25OHD levels lower than 30 ng/ml and 78.4% had a low calcium intake. We did not find any correlations between BMD Z-scores, lung function or 25OHD levels. Patients with fat free mass (FFM) below the third percentile had BMD Z-score lower than -1 more frequently, in both locations (p < 0.006 and p < 0.001, respectively).Conclusions: although most assessed patients had normal BMD and normal lung function, a high proportion had low: FFM, calcium intake and 25OHD levels. The association between low FFM and low BMD highlights the importance of improving body composition in CF patients, in order to prevent future CFBD


Introducción: la fibrosis quística (FQ) es la enfermedad hereditaria más frecuente en la población caucásica. La mayor sobrevida alcanzada ha favorecido la aparición de la enfermedad ósea (EO) asociada, con el consiguiente aumento del riesgo de fracturas. Objetivo: evaluar la asociación de la densidad mineral ósea (DMO) con la función pulmonar y con la concentración plasmática de 25-hidroxivitamina D (25OHD) en niños y adolescentes con FQ. Métodos: estudio transversal y multicentrico, de pacientes con FQ de entre cinco y 18 años, clínicamente estables. Se evaluó peso, talla, desarrollo puberal, DMO y composición corporal (DXA), función pulmonar (FEF25-75 y VEF1), 25OHD plasmática e ingesta alimentaria y actividad física por encuestas. Se consideró una diferencia significativa si p < 0,05. Resultados: ingresaron 37 pacientes, 51% con función pulmonar normal. Los DMO-z promedio en columna lumbar y cuerpo total sin cabeza fueron -0,4 y -0,5, respectivamente. El 27% tuvo un índice de masa libre de grasa (IMLG) < p3, el 89% tuvo niveles insuficientes o deficientes de 25OHD y el 78,4% tuvo déficit de ingesta de calcio. No encontramos correlación entre el DMO-z con la función pulmonar ni con la concentración de 25OHD. Los pacientes con MLG < p3 tuvieron con mayor frecuencia DMO-z baja o en riesgo, en ambas localizaciones (p = 0,006 y p = 0,001 respectivamente). Conclusiones: aunque la mayoría de los pacientes tuvo una DMO y una función pulmonar normal, una alta proporción de sujetos presentaron déficit de MLG, baja ingesta de calcio y deficit de 25OHD. La asociación entre déficit de MLG y menor DMO revela la importancia de mejorar este factor para prevenir la enfermedad ósea futura


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Composição Corporal , Densidade Óssea , Fibrose Cística/metabolismo , Testes de Função Respiratória , Vitamina D/metabolismo , Chile/epidemiologia , Estudos Transversais , Fibrose Cística/sangue , Fibrose Cística/fisiopatologia , Hidroxicolecalciferóis/sangue , Estado Nutricional
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