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1.
Rev. biol. trop ; 71(1): e54971, dic. 2023. graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1550734

RESUMO

Resumen Introducción: Poco se conoce del potencial dendrocronológico de las Podocarpáceas en el trópico. Objetivo: Explorar el potencial dendrocronológico de tres especies de podocarpáceas: Retrophyllum rospigliosii, Podocarpus oleifolius y Prumnopitys harmsiana. Métodos: De plantaciones no manejadas localizadas en los Andes colombianos, se muestrearon y analizaron 88 árboles: 30 muestras de R. rospigliosii provenientes de secciones transversales, 30 y 28 muestras de P. oleifolius y P. harmsiana, respectivamente, provenientes de núcleos de madera extraídos con barreno de incrementos. Las muestras se procesaron siguiendo las técnicas dendrocronológicas estándar. Resultados: En general, las características anatómicas de los anillos de crecimiento son similares para las tres especies, con una anatomía simple de traqueidas alineadas radialmente por tratarse de coníferas. Dado que la edad conocida de la plantación coincide con el número de anillos se considera una fuerte evidencia de la frecuencia anual de su formación en R. rospigliosii y P. oleifolius, las cuales presentaron buena sincronización (cofechado) con una inter-correlación promedio de 0.55 (r-Pearson). Para P. harmsiana no fue posible concretar series de ancho de anillos de las muestras recolectadas. Las series estandarizadas de R. rospigliosii y P. oleifolius mostraron una relación con los registros instrumentales de precipitación y temperatura, indicando que estas especies pueden ser promisorias para estudios adicionales. Conclusión: La investigación dendrocronología con especies de Podocarpáceas podría realizarse exitosamente con R. rospigliosii y P. oleifolius, pero no con P. harmsiana.


Abstract Introduction: Little is known about the dendrochronological potential of Podocarpaceaes in the tropics. Objective: To explore the dendrochronological potential of three Podocarpaceae species: Retrophyllum rospigliosii, Podocarpus oleifolius, and Prumnopitys harmsiana. Methods: From a non-managed plantation in the Andean cordillera in Colombia, a total of 88 trees were analyzed: 30 samples of cross-sections of R. rospigliosii, and 30 and 28 samples of P. oleifolius and P. harmsiana, respectively, obtained with an increment borer. Samples were processed according to standard dendrochronological methods. Results: The anatomical characteristics of the growth rings of the three species are similar, with a simple conifer anatomy with radially oriented tracheids. Since the known age of the plantation coincides with the number of tree rings this is strong evidence of annual tree-ring frequency of R. rospigliosii and P. oleifolius which also showed a satisfactory cross-dating with an average inter-correlation of 0.55 (r-Pearson). For P. harmsiana, it was not possible to build a tree-ring series from the collected samples. R. rospigliosii and P. oleifolius standardized ring-width chronologies showed a relationship with the instrumental records of rainfall and temperature, indicating these species may be promising further studies. Conclusions: Dendrochronological research with Podocarpaceae species could be carried out successfully with R. rospigliosii and P. oleifolius but not with P. harmsiana.


Assuntos
Desenvolvimento Vegetal/fisiologia , Traqueófitas/crescimento & desenvolvimento , Senescência Vegetal/fisiologia , Árvores/crescimento & desenvolvimento , Colômbia , Crescimento e Desenvolvimento
3.
BMC Pediatr ; 19(1): 260, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31349791

RESUMO

BACKGROUND: Education and health are crucial topics for public policies as both largely determine the future wellbeing of the society. Currently, several studies recognize that physical activity (PA) benefits brain health in children. However, most of these studies have not been carried out in developing countries or lack the transference into the education field. The Cogni-Action Project is divided into two stages, a cross-sectional study and a crossover-randomized trial. The aim of the first part is to establish the associations of PA, sedentarism, and physical fitness with brain structure and function, cognitive performance and academic achievement in Chilean schoolchildren (10-13 years-old). The aim of the second part is to determinate the acute effects of three PA protocols on neuroelectric indices during a working memory and a reading task. METHODS: PA and sedentarism will be self-reported and objectively-assessed with accelerometers in a representative subsample, whilst physical fitness will be evaluated through the ALPHA fitness test battery. Brain structure and function will be assessed by magnetic resonance imaging (MRI) in a randomized subsample. Cognitive performance will be assessed through the NeuroCognitive Performance Test, and academic achievement by school grades. In the second part 32 adolescents (12-13 year-old) will be cross-over randomized to these condition (i) "Moderate-Intensity Continuous Training" (MICT), (ii) "Cooperative High-Intensity Interval Training" (C-HIIT), and (iii) Sedentary condition. Neuroelectric indices will be measures by electroencephalogram (EEG) and eye-tracking, working memory by n-back task and reading comprehension by a reading task. DISCUSSION: The main strength of this project is that, to our knowledge, this is the first study analysing the potential association of PA, sedentarism, and physical fitness on brain structure and function, cognitive performance, and academic achievement in a developing country, which presents an important sociocultural gap. For this purpose, this project will use advanced technologies in neuroimaging (MRI), electrophysiology (EEG), and eye-tracking, as well as objective and quality measurements of several physical and cognitive health outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03894241 Date of register: March 28, 2019. Retrospectively Registered.


Assuntos
Sucesso Acadêmico , Encéfalo/fisiologia , Cognição , Exercício Físico/psicologia , Aptidão Física , Acelerometria , Adolescente , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Criança , Chile , Estudos Cross-Over , Estudos Transversais , Eletroencefalografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Comportamento Sedentário
4.
Rev. cuba. med ; 54(4): 280-287, oct.-dic. 2015. ilus, tab
Artigo em Espanhol | LILACS, CUMED | ID: lil-771008

RESUMO

INTRODUCCIÓN: el cáncer de pulmón es un problema de salud que afecta de forma significativa a la humanidad. OBJETIVO: describir las características clínicas de la enfermedad y su asociación con la variedad histológica. MÉTODOS: se realizó un estudio descriptivo transversal en 107 pacientes con cáncer de pulmón hospitalizados en los servicios de Medicina Interna y Neumología del Hospital "Hermanos Ameijeiras", en el período de marzo 2012 a febrero de 2013. RESULTADOS: el 66,4 % de los pacientes fueron hombres con una edad media de 65,9 años y el 61,7 %, fumadores. La forma clínica de presentación más común fue la bronconeumónica en el 20,6 %, y el síntoma, la tos en 63,6 %. En el adenocarcinoma de pulmón, el 30,4 % presentó la forma bronconeumónica. CONCLUSIONES: la atelectasia y la forma clínica de presentación pleural se asociaron al carcinoma escamoso y al adenocarcinoma, respectivamente.


INTRODUCTION: lung cancer is a health problem that significantly affects how mankind. OBJECTIVE: describe the clinical features and its association with histological subtype in patients with lung cancer. METHODS: across-sectional study was conducted in 107 patients with lung cancer hospitalized in the services of internal medicine and pneumology at Hermanos Ameijeiras Hospital from March 2012 to February 2013. RESULTS: 66.4 % of the patients were men with a mean age of 65.9 years and 61.7 % had smoking habits. Broncho-pneumonia was the most common clinical form of presentation in 20.6 % and symptom, cough in 63.6 %. In lung adeno-carcinoma, 30.4 % had the broncho-pneumonic form. CONCLUSIONS: atelectasis and pleural clinical form of presentation were associated with squamous cell carcinoma and adeno-carcinoma, respectively.


Assuntos
Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/etnologia , Neoplasias Pulmonares/história , Neoplasias Pulmonares/prevenção & controle , Epidemiologia Descritiva , Estudos Transversais
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